JP6006928B2 - Method for producing polymer compound - Google Patents

Description

The present invention is useful as a base component of the resist composition, and relates to the production how of the polymer compound which can be produced irrespective of the type of the monomers used.

In lithography technology, for example, a resist film made of a resist material is formed on a substrate, and the resist film is selectively exposed and developed to form a resist pattern having a predetermined shape on the resist film. The process to perform is performed. A resist material in which the exposed portion of the resist film changes to a property that dissolves in the developer is referred to as a positive type, and a resist material that changes to a property in which the exposed portion does not dissolve in the developer is referred to as a negative type.
In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization has been rapidly progressing due to advances in lithography technology.
As a technique for miniaturization, the exposure light source is generally shortened in wavelength (increased energy). Specifically, conventionally, ultraviolet rays typified by g-line and i-line have been used, but at present, mass production of semiconductor elements using a KrF excimer laser or an ArF excimer laser has started. Further, studies have been made on EUV (extreme ultraviolet), EB (electron beam), X-rays, and the like having a shorter wavelength (higher energy) than these excimer lasers.

Resist materials are required to have lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing a pattern with fine dimensions.
Conventionally, as a resist material satisfying such requirements, there is a chemically amplified resist composition containing a base material component whose solubility in a developing solution is changed by the action of an acid and an acid generator component that generates an acid upon exposure. It is used. For example, when the developer is an alkali developer (alkaline development process), the positive chemically amplified resist composition includes a resin component (base resin) whose solubility in an alkali developer is increased by the action of an acid, an acid Those containing a generator component are generally used. When a resist film formed using such a resist composition is selectively exposed at the time of forming a resist pattern, an acid is generated from the acid generator component in the exposed portion, and the acid acts on the alkaline developer of the base resin. Solubility increases and the exposed part becomes soluble in an alkaline developer. Therefore, by performing alkali development, a positive pattern in which an unexposed portion remains as a pattern is formed.
Here, as the base resin, a resin whose polarity is increased by the action of an acid is used, and the solubility in an alkali developer is increased while the solubility in an organic solvent is decreased. Therefore, when a solvent development process using an organic solvent-containing developer (organic developer) is applied instead of an alkali development process, the solubility in the organic developer is relatively reduced in the exposed area. In the solvent development process, the unexposed portion of the resist film is dissolved and removed by the organic developer, and a negative resist pattern is formed in which the exposed portion remains as a pattern. Such a solvent development process for forming a negative resist pattern is sometimes referred to as a negative development process (for example, Patent Document 1).

At present, as a base resin of a chemically amplified resist composition used in ArF excimer laser lithography and the like, it has a structural unit derived from (meth) acrylic acid ester in its main chain because of its excellent transparency near 193 nm. Resins (acrylic resins) and the like are generally used (see, for example, Patent Document 2).
Here, “(meth) acrylic acid ester” means one or both of an acrylic acid ester having a hydrogen atom bonded to the α-position and a methacrylic acid ester having a methyl group bonded to the α-position. “(Meth) acrylate” means one or both of an acrylate having a hydrogen atom bonded to the α-position and a methacrylate having a methyl group bonded to the α-position. “(Meth) acrylic acid” means one or both of acrylic acid having a hydrogen atom bonded to the α-position and methacrylic acid having a methyl group bonded to the α-position.

  In recent years, a base resin having an acid generating group that decomposes upon exposure to generate an acid has been proposed. For example, a resin component having an acid-generating group that generates an acid upon exposure and an acid-decomposable group that changes its polarity by the action of an acid has been proposed in the structure (see, for example, Patent Documents 3 to 5). Such a resin component has both a function as an acid generator and a function as a base material component, and a chemical amplification resist composition can be constituted by only one component. In other words, when the resin component is exposed to light, an acid is generated from the acid-generating group in the structure, the acid-decomposable group is decomposed by the action of the acid, and a polar group such as a carboxy group is generated to increase the polarity. To do. Therefore, if selective exposure is performed on a resin film (resist film) formed using the resin component, the polarity of the exposed portion increases. Therefore, development using an alkaline developer dissolves the exposed portion. And a positive resist pattern is formed.

JP 2009-25707 A JP 2003-241385 A JP-A-10-221852 JP 2006-045311 A JP 2010-095643 A

  According to the resin component having an acid-generating group and an acid-decomposable group as described in Patent Documents 3 to 5, the resolution is higher than when the acid generator and the base component are blended separately. It is said that the property is improved. The reason why the resolution is improved is that the resin component as a base component has an acid generating group, and the acid generating group is easily distributed uniformly in the resist film. It is conceivable that the acid to be easily diffused uniformly in the resist film. The resin component is generally produced by a normal radical polymerization method using a monomer that induces a repeating unit constituting the resin.

However, the resin component as described above has poor removal efficiency of unreacted monomers at the time of production of the resin component, and in particular, removal efficiency of a monomer containing an acid generating group that generates an acid upon exposure is poor. Therefore, due to the influence of this unreacted monomer (residual monomer), there is a problem that it is difficult to obtain the required lithography characteristics when a resist pattern is formed using a resist composition containing the resin component.
Further, in the production of the resin as described above, there is a problem that the resin cannot be produced when a monomer containing some acid-generating groups is used. Therefore, there is a problem that it is difficult to optimize the acid generating group according to the required lithography characteristics and lithography conditions because the selection range of the acid generating group used for the resin is narrow.

  The present invention has been made in view of the above circumstances, is useful as a base component of a resist composition having excellent lithography properties, and can be produced regardless of the type of monomer used. It is an object of the present invention to provide a method for producing a polymer compound that decomposes and generates an acid, a resist composition containing the polymer compound, and a resist pattern forming method using the resist composition.

In order to solve the above problems, the present invention employs the following configuration.
That is, the first aspect of the present invention is at least one anionic group selected from the group consisting of a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methide anion. And a polymer having a first sulfonium or iodonium cation to synthesize a precursor polymer, washing, and then subjecting the precursor polymer to a salt exchange with the second sulfonium or iodonium cation. a manufacturing method, the second sulfonium or iodonium cation, the high hydrophobicity than the first sulfonium or iodonium cation, as measured by high performance liquid chromatography, the second sulfonium or iodonium cationite The value obtained by dividing the retention time of the first sulfonium or iodonium cation by the retention time of the first sulfonium or iodonium cation measured by the high performance liquid chromatography method under the same conditions as the measurement of the retention time of the second sulfonium or iodonium cation. It is a manufacturing method of the high molecular compound which has the structural unit which decomposes | disassembles by exposure and generate | occur | produces an acid characterized by being 05 or more.

In the present specification and claims, “exposure” is a concept including general irradiation of radiation.
“Aliphatic” is a relative concept with respect to aromatics, and is defined to mean groups, compounds, etc. that do not have aromaticity.
Unless otherwise specified, the “alkyl group” includes linear, branched and cyclic monovalent saturated hydrocarbon groups. The same applies to the alkyl group in the alkoxy group.
The “alkylene group” includes linear, branched, and cyclic divalent saturated hydrocarbon groups unless otherwise specified.
“Halogenated alkyl group” is a group in which some or all of the hydrogen atoms in the alkyl group are substituted with halogen atoms. “Halogenated alkylene group” is in which some or all of the hydrogen atoms in the alkylene group are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
A “fluorinated alkyl group” is a group in which some or all of the hydrogen atoms in the alkyl group are substituted with fluorine atoms. A “fluorinated alkylene group” is a group in which some or all of the hydrogen atoms in the alkylene group are substituted with fluorine atoms. Group.
In the present specification, “polymer compound” or “resin” refers to a polymer having a molecular weight of 1000 or more. In the case of a polymer compound, the “molecular weight” is a polystyrene-reduced mass average molecular weight measured by GPC (gel permeation chromatography).
“Structural unit” means a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer).

  INDUSTRIAL APPLICABILITY According to the present invention, a method for producing a polymer compound that is useful as a base component of a resist composition having excellent lithography properties and that can be produced regardless of the type of monomer used, and the polymer compound And a resist pattern forming method using the resist composition.

≪Method for producing polymer compound≫
In the method for producing a polymer compound of the present invention, a monomer having an anion group and a sulfonium or iodonium cation is polymerized to synthesize a precursor polymer, washed, and then the precursor polymer is subjected to salt exchange with a sulfonium or iodonium cation. A method for producing a polymer compound to be produced, wherein a sulfonium or iodonium cation used for salt exchange is more hydrophobic than a sulfonium or iodonium cation in the monomer, and decomposes by exposure to generate an acid. This is a method for producing a polymer compound (hereinafter sometimes simply referred to as “production method”). In the present specification, the “monomer having an anion group and a sulfonium or iodonium cation” may be referred to as an “anion group-containing monomer”.
The polymer compound produced by this production method generates an acid upon exposure. Specifically, at least a part of the structural unit derived from the anion-containing monomer constituting the polymer compound, the cation part of which is salt-exchanged with a sulfonium or iodonium cation, is decomposed by exposure. Generates an acid.

The structural unit derived from an anion group-containing monomer refers to a structural unit formed by cleavage of an ethylenic double bond or the like of the monomer.
The polymer compound produced by the production method according to the present invention is suitable as a base resin used for the base component of the resist composition.
Hereinafter, for the method for producing such a polymer compound, a precursor polymer is synthesized by polymerizing an anion group-containing monomer and washed, and the precursor polymer synthesized in step (i) is converted to a sulfonium or iodonium cation. Each step will be described separately for the salt exchange step (ii).

<Process (i)>
Step (i) is a step of polymerizing a monomer having an anion group and a sulfonium or iodonium cation (an anion group-containing monomer) to synthesize a precursor polymer and washing.
Specifically, the precursor polymer can be synthesized by dissolving at least an anion group-containing monomer in a polymerization solvent and adding a polymerization initiator to the polymerization solvent.

The anion group-containing monomer will be described later.
In the present invention, in addition to the anion group-containing monomer, a monomer that induces a structural unit to be introduced into the polymer compound may be used as necessary. The monomer for deriving the structural unit introduced into the polymer compound as necessary is not particularly limited as long as it is copolymerizable with the anion group-containing monomer, and specifically, the structural unit described below ( Examples include monomers that derive a1) to (a6). As the monomer, a commercially available monomer may be used, or a monomer synthesized using a known method may be used.

  The amount of each monomer (an anion group-containing monomer, a monomer for deriving each structural unit introduced as necessary) is determined in consideration of the desired copolymer composition ratio, that is, the proportion of each structural unit in the polymer compound. And may be determined as appropriate. A preferable copolymer composition ratio in the polymer compound used as the base component of the resist composition will be described later in the second embodiment.

The polymerization initiator is not particularly limited, and examples thereof include radical polymerization initiators such as azobisisobutyronitrile (AIBN) and dimethyl azobisisobutyrate.
Any polymerization solvent may be used as long as it can dissolve the anion group-containing monomer as a raw material and a monomer for deriving each structural unit introduced as necessary. Ethyl lactate, γ-butyrolactone, methyl ethyl ketone, propylene glycol monomethyl ether Examples thereof include acetate, tetrahydrofuran, cyclohexanone, or a mixed solvent thereof.

Further, the during the _{polymerization, HS-CH 2 -CH 2 -CH} 2 -C (CF 3) By use of a chain transfer agent such as 2 -OH, -C terminated _{(CF 3)} 2 -OH group May be introduced. As described above, a copolymer introduced with a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is substituted with a fluorine atom reduces development defects and LER (line edge roughness: uneven unevenness of line side walls). It is effective in reducing

50-100 degreeC is preferable and, as for reaction temperature, 65-85 degreeC is more preferable.
The reaction time varies depending on the reactivity between the monomers and the reaction temperature, but is usually preferably 60 to 480 minutes, more preferably 120 to 420 minutes.
After polymerizing the monomer, the precursor polymer is obtained by, for example, dropping the reaction polymerization solution into a large amount of water or an organic solvent (isopropanol, heptane, methanol, etc.) to precipitate the polymer, followed by filtration and the like. can get.

In the first aspect, by washing the precursor polymer obtained as described above with an organic solvent or the like, an unreacted residual monomer that can be dissolved in the organic solvent before starting the step (ii) described below. Remove. Specifically, preferred examples include dispersion cleaning, cleaning by re-dissolution / reprecipitation, and cleaning by liquid-liquid cleaning. By removing the residual monomer, it is possible to improve lithography characteristics when a resist pattern is formed using the resist composition containing the polymer compound of the present invention. In addition, the polymer having a cation with low hydrophobicity is easier to remove by washing the residual monomer than the polymer having a cation with high hydrophobicity, so that the cation is highly hydrophobic in the step (ii) described later. By performing washing before salt exchange with cations, the residual monomer can be particularly preferably reduced.
As the organic solvent used for dispersion washing, a polar solvent is preferable. For example, alcohol solvents such as methanol and isopropanol are preferable, and other dimethyl sulfoxide (DMSO), N, N-dimethylformamide, N-methylpyrrolidone and the like are also preferably used. it can.
At the time of cleaning by re-dissolution / re-precipitation, for example, water or a solvent such as isopropanol, heptane, methanol or the like is used.
During washing by liquid-liquid washing, a poor solvent that does not dissolve the precursor polymer (for example, a hydrocarbon solvent or an ether solvent) and a good solvent that dissolves the precursor polymer (for example, an organic solvent such as dimethyl sulfoxide or dimethylformamide, or water And a mixed solvent of polar solvent) may be used in combination.

<Process (ii)>
Step (ii) is a step of subjecting the precursor polymer synthesized in step (i) to salt exchange with a sulfonium or iodonium cation. The sulfonium or iodonium cation used in step (ii) is more hydrophobic than the monomer sulfonium or iodonium cation used in the synthesis of the precursor polymer in step (i).
Hereinafter, the sulfonium or iodonium cation used in step (ii) may be referred to as “second sulfonium or iodonium cation” in order to distinguish from the sulfonium or iodonium cation of the anion group-containing monomer used for the precursor polymer synthesis.

In the present invention, the hydrophobicity of the cation can be compared by the retention time (retention time) when two or more control cations are analyzed under the same conditions by a high performance liquid chromatography (HPLC) method. That is, in the present invention, in the HPLC method, a cation with a relatively long retention time is referred to as a “highly hydrophobic cation”, and a cation with a relatively short retention time is referred to as a “low hydrophobic cation”. The apparatus and conditions used for the HPLC method are not particularly limited as long as they are generally used for analyzing compounds and can analyze the cations in steps (i) and (ii). . Specifically, for example, it can be measured under the following conditions.
Eluent (developing solvent): acetonitrile / buffer solution (50/50 volume ratio)
Buffer solution: trifluoroacetic acid / ion exchange water (0.1% by mass).
Apparatus: Dionex U3000 (manufactured by Dionex).
Column: Superiorex-ODX (manufactured by Shiseido Co., Ltd.).
Detector: Corona CAD (manufactured by ESA Biosciences).
Flow rate: 1 mL / min.
Column temperature: 30 ° C
Sample concentration: acetonitrile solution with a solid content of 0.1% by mass Injection volume: 2 μl
The sample concentration indicates the solid content concentration of a compound in which the anion is Br ⁻ and the cation has various target structures.

Salt exchange is performed in a two-layer system of water and organic solvent. The precursor polymer synthesized in the step (i) can be appropriately used as long as it can be separated from an appropriate organic solvent (water and can dissolve the precursor polymer. For example, cyclohexanone, methyl ethyl ketone, propylene glycol. A compound having a second sulfonium or iodonium cation dissolved in a solvent such as monomethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, ethyl acetate, propionitrile, or a mixed solvent thereof (for salt exchange) Compound) can be added and stirred. About the reaction temperature mentioned later about the compound for salt exchange, about 10-30 degreeC is preferable, and about 15-25 degreeC is more preferable.
The reaction time varies depending on the reactivity of the precursor polymer and the salt exchange compound, the reaction temperature, and the like, but it is usually preferably 0.5 minutes or more and 24 hours or less.
The amount of the salt exchange compound used in such salt exchange is usually preferably about 1 to 5 moles with respect to 1 mole of the monomer for deriving the structural unit having the first sulfonium or iodonium cation in the precursor polymer.
In addition, the substance amount of the monomer for deriving the structural unit having the first sulfonium or iodonium cation in the precursor polymer is a copolymer composition ratio (structure) determined by carbon 13 nuclear magnetic resonance spectrum (600 MHz — ¹³ C-NMR). It can be calculated by conversion from the ratio (molar ratio) of each structural unit in the formula.

After completion of the salt exchange reaction between the precursor polymer and the compound for salt exchange, it is preferable to isolate and purify the polymer compound (final target product) in the reaction solution.
For isolation and purification, conventionally known methods can be used. For example, concentration, water washing, organic solvent washing, solvent extraction, distillation, crystallization, recrystallization, chromatography, etc. can be used alone or in combination of two or more. They can be used in combination.

[Monomer having an anionic group and a sulfonium or iodonium cation]
A monomer having an anionic group and a sulfonium or iodonium cation becomes a constituent unit constituting the precursor polymer by polymerization in the step (i). In the structural unit, at least a part of the structure is decomposed by exposure to generate an acid.
In addition, the cation part (sulfonium or iodonium cation) in the monomer is capable of salt exchange with the second sulfonium or iodonium cation by salt exchange in the step (ii), and more than the second sulfonium or iodonium cation. Low hydrophobicity.
In this specification, in order to distinguish from the second sulfonium or iodonium cation used in step (ii), the sulfonium or iodonium cation in the monomer used in step (i) is referred to as “first sulfonium or iodonium cation”. is there.

(Anionic group)
The anion group in the anion group-containing monomer is not particularly limited, but is selected from the group consisting of a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methide anion. It is preferable that it is at least one kind of group.
Among these, as the anionic group, groups represented by the following formulas (an1) to (an4) are preferable.

［Ｗ^０は置換基を有していてもよい炭素数１〜３０の炭化水素基である。Ｚ^３は−Ｃ（＝Ｏ）−Ｏ−、−ＳＯ_２−又は置換基を有していてもよい炭化水素基であり、Ｚ^４及びＺ^５はそれぞれ独立に−Ｃ（＝Ｏ）−又は−ＳＯ_２−である。Ｒ^６２及びＲ^６３はそれぞれ独立にフッ素原子を有していてもよい炭化水素基である。Ｚ^１は−Ｃ（＝Ｏ）−、−ＳＯ_２−、−Ｃ（＝Ｏ）−Ｏ−又は単結合であり、Ｚ^２は−Ｃ（＝Ｏ）−又は−ＳＯ_２−である。Ｒ^６１はフッ素原子を有していてもよい炭化水素基である。Ｒ^６４はフッ素原子を有していてもよい炭化水素基である。］

[W ⁰ is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent. Z ³ is —C (═O) —O—, —SO ₂ — or an optionally substituted hydrocarbon group, and Z ⁴ and Z ⁵ are each independently —C (═O) — or -SO ₂ - is. R ⁶² and R ⁶³ are each independently a hydrocarbon group optionally having a fluorine atom. Z ¹ is —C (═O) —, —SO ₂ —, —C (═O) —O— or a single bond, and Z ² is —C (═O) — or —SO ₂ —. R ⁶¹ is a hydrocarbon group which may have a fluorine atom. R ⁶⁴ is a hydrocarbon group which may have a fluorine atom. ]

In Formula (an1), W ⁰ is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent.
The hydrocarbon group having 1 to 30 carbon atoms which may have a substituent of W ⁰ may be an aliphatic hydrocarbon group or an aromatic group.
An aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
More specific examples of the aliphatic hydrocarbon group for W ⁰ include a linear or branched aliphatic hydrocarbon group and an aliphatic hydrocarbon group containing a ring in the structure.

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 5 carbon atoms.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable. Specifically, a methylene group [—CH ₂ —], an ethylene group [— (CH ₂ ) ₂ —], a trimethylene group [ — (CH ₂ ) ₃ —], tetramethylene group [— (CH ₂ ) ₄ —], pentamethylene group [— (CH ₂ ) ₅ —] and the like can be mentioned.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specifically, —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ). _{2 -, - C (CH 3} ) (CH 2 CH 3) -, - C (CH 3) (CH 2 CH 2 CH 3) -, - C (CH 2 CH 3) 2 - ; alkylethylene groups such as - _{CH (CH 3) CH 2 -} , - CH (CH 3) CH (CH 3) -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - C (CH 2 CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) _{CH 2 CH 2 CH 2 -,} - CH 2 CH (CH 3) CH 2 CH 2 - And the like alkyl alkylene group such as an alkyl tetramethylene group of. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.
The linear or branched aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and an oxo group (═O).

As the aliphatic hydrocarbon group containing a ring in the structure, a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in the ring structure (excluding two hydrogen atoms from the aliphatic hydrocarbon ring) Group), a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and the cyclic aliphatic hydrocarbon group is a linear or branched chain fatty acid. Group intervening in the middle of the group hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those described above.
The cyclic aliphatic hydrocarbon group (aliphatic cyclic group) preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be polycyclic or monocyclic. As the monocyclic aliphatic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, Examples include norbornane, isobornane, tricyclodecane, and tetracyclododecane.
The cyclic aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxo group (═O).
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.
In the cyclic aliphatic hydrocarbon group, a part of carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing the hetero atom, —O—, —C (═O) —O—, —S—, —S (═O) ₂ —, and —S (═O) ₂ —O— are preferable.

The aromatic group in W ⁰ is a divalent hydrocarbon group having at least one aromatic ring and may have a substituent.
The aromatic ring in W ⁰ is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. It is preferable that carbon number of an aromatic ring is 5-30, 5-20 are more preferable, 6-15 are more preferable, and 6-12 are especially preferable. However, the carbon number does not include the carbon number in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; aromatic heterocycles in which a part of carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; etc. Is mentioned. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, the aromatic group in W ⁰ is a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocyclic ring (arylene group or heteroarylene group); an aromatic group containing two or more aromatic rings A group obtained by removing two hydrogen atoms from a compound (for example, biphenyl, fluorene, etc.); a hydrogen atom of a group (aryl group or heteroaryl group) obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle A group substituted with an alkylene group (for example, an aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc. A group in which one hydrogen atom is further removed); The alkylene group bonded to the aryl group or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.
The aromatic group may or may not have a substituent. For example, a hydrogen atom bonded to an aromatic ring of the aromatic group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxo group (═O).
The alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent are the same as the alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent of the cyclic aliphatic hydrocarbon group. It is.
Especially, group represented by a following formula (an1-1) is preferable.

［式中、Ｒ^ｆ１及びＲ^ｆ２はそれぞれ独立に水素原子、アルキル基、フッ素原子、又はフッ素化アルキル基であり、Ｒ^ｆ１、Ｒ^ｆ２のうち少なくとも１つはフッ素原子又はフッ素化アルキル基であり、ｐ０は１〜８の整数である。］

[Wherein, R ^f1 and R ^f2 each independently represent a hydrogen atom, an alkyl group, a fluorine atom, or a fluorinated alkyl group, and at least one of R ^f1 and R ^f2 is a fluorine atom or a fluorinated alkyl group. , P0 is an integer of 1-8. ]

R ^f1 and R ^f2 are each independently a hydrogen atom, an alkyl group, a fluorine atom, or a fluorinated alkyl group, and at least one of R ^f1 and R ^f2 is a fluorine atom or a fluorinated alkyl group.
As the alkyl group for R ^f1 and R ^f2 , an alkyl group having 1 to 5 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group. Group, pentyl group, isopentyl group, neopentyl group and the like.
Examples of the fluorinated alkyl group of ^{R f1,} R ^f2, group in which part or all of the hydrogen atoms of the alkyl group of the ^{R f1, R f2} is substituted with a fluorine atom is preferred.
R ^f1 and R ^f2 are preferably a fluorine atom or a fluorinated alkyl group.
In formula (an1-1), p0 is an integer of 1 to 8, preferably an integer of 1 to 4, and more preferably 1 or 2.
Moreover, as a hydrocarbon group which may have a substituent of W ⁰ , preferred examples other than the above formula (an1-1) include an aliphatic cyclic group or an aromatic group which may have a substituent. It is preferably a group such as adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, camphor, benzene, etc., which is a group in which two or more hydrogen atoms have been removed (which may have a substituent). It is more preferable.

In formula (an2), Z ³ represents —C (═O) —O—, —SO ₂ — or a hydrocarbon group which may have a substituent. Examples of the hydrocarbon group which may have a substituent for Z ³ include the same hydrocarbon groups as those having 1 to 30 carbon atoms which may have a substituent for W ⁰ . Among these, Z ³ is preferably —SO ₂ —.
In formula (an2), Z ⁴ and Z ⁵ are each independently —C (═O) — or —SO ₂ —, preferably at least one is —SO ₂ —, and both are —SO _2. -Is more preferable.
R ⁶² and R ⁶³ are each independently a hydrocarbon group which may have a fluorine atom, and examples thereof include those similar to the hydrocarbon group which may have a fluorine atom in R ⁶¹ described later. .

In formula (an3), Z ¹ represents —C (═O) —, —SO ₂ —, —C (═O) —O—, or a single bond. When Z ¹ is a single bond, N ^{− in} the formula is preferably not directly bonded to —C (═O) — on the side opposite to the side bonded to Z ² (that is, the left end in the formula).

In formula (an3), Z ² represents —C (═O) — or —SO ₂ —, and preferably —SO ₂ —.
R ⁶¹ is a hydrocarbon group which may have a fluorine atom. Examples of the hydrocarbon group for R ⁶¹ include an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, and an aralkyl group.
The alkyl group for R ⁶¹ is preferably one having 1 to 8 carbon atoms, more preferably one having 1 to 6 carbon atoms, still more preferably one having 1 to 4 carbon atoms, and even if linear, it is branched. It may be a chain. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group and the like are preferable.
The monovalent alicyclic hydrocarbon group in R ⁶¹ is preferably those having 3 to 20 carbon atoms, more preferably those having 3 to 12 carbon atoms, and may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclobutane, cyclopentane, and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms. Adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.
The aryl group in R ⁶¹ is preferably those having 6 to 18 carbon atoms, more preferably those having 6 to 10 carbon atoms, and particularly preferably a phenyl group.
Aralkyl group in R ⁶¹ include those in which the "aryl group for R ^61" alkylene group and the above C1-8 bonded are preferred examples. More preferred is an aralkyl group in which an alkylene group having 1 to 6 carbon atoms and the above “aryl group in R ⁶¹ ” are bonded, and an aralkyl group in which an alkylene group having 1 to 4 carbon atoms and the above “aryl group in R ⁶¹ ” are bonded. Is particularly preferred.
In the hydrocarbon group for R ⁶¹ , part or all of the hydrogen atoms of the hydrocarbon group are preferably substituted with fluorine atoms, and 30 to 100% of the hydrogen atoms of the hydrocarbon group are substituted with fluorine atoms. More preferably. Especially, it is especially preferable that it is the perfluoroalkyl group by which all the hydrogen atoms of the alkyl group mentioned above were substituted by the fluorine atom.

In the formula (an4), R ⁶⁴ represents a hydrocarbon group that may have a fluorine atom. As the hydrocarbon group for R ⁶⁴ , an alkylene group, a divalent alicyclic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from an aryl group, a group in which one or more hydrogen atoms have been removed from an aralkyl group, etc. Is mentioned.
Specific examples of the hydrocarbon group for R ⁶⁴ include those exemplified in the description of the hydrocarbon group for R ⁶¹ (an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, an aralkyl group, and the like). And a group in which one or more hydrogen atoms are removed.
In the hydrocarbon group for R ⁶⁴ , part or all of the hydrogen atoms of the hydrocarbon group are preferably substituted with fluorine atoms, and 30 to 100% of the hydrogen atoms of the hydrocarbon group are substituted with fluorine atoms. More preferably.

Among the above, for example, when the anion group is a group having a fluorine atom among groups represented by the formula (an1) (particularly a group represented by the formula (an1-1)), or represented by (an2) Or a group represented by the formula (an3) in which Z ¹ and Z ² are —SO ₂ —, the fluorinated alkylsulfonic acid anion, carbanion, sulfonylimide anion, etc. It is possible to generate a relatively strong acid.
On the other hand, when the anion group does not have a fluorine atom among the groups represented by the formula (an1), the group represented by the formula (an4), and Z ¹ and Z ² are —C (═O) —. When it has a group represented by a certain formula (an3), a relatively weak acid such as an alkyl sulfonate anion, an aryl sulfonate anion, a carboxylate anion, and an imide anion can be generated from the anion group by exposure.

Since an acid having a desired acid strength can be generated depending on the type of anionic group as described above, an anionic group is appropriately selected according to the required characteristics of the resist composition using the polymer compound produced according to the present invention. You can choose. For example, when the anion group plays a role similar to that of an acid generator usually used in a resist composition, it is preferable to select an anion group that generates a strong acid.
In addition, for example, when the anion group has the same function as a quencher (a quencher that salt exchanges with a strong acid generated from an acid generator and traps a strong acid) used in a resist composition, a weak acid is generated. It is preferred to select an anionic group.
Here, the strong acid and the weak acid are the relationship with the activation energy of an acid-decomposable group that is decomposed by the action of an acid as contained in the structural unit (a1) described later, and the acid generator acid used together. It is determined in relation to strength. Therefore, the above-mentioned “relatively weak acid” cannot always be used as a quencher.

Examples of the anion group-containing monomer include those in which the above anion group is directly bonded to a polymerizable group via a linking group or not via a linking group.
Examples of the polymerizable group include vinyl, allyl, acryloyl, methacryloyl, fluorovinyl, difluorovinyl, trifluorovinyl, difluorotrifluoromethylvinyl, trifluoroallyl, perfluoroallyl, Fluoromethylacryloyl group, nonylfluorobutylacryloyl group, vinyl ether group, fluorine-containing vinyl ether group, allyl ether group, fluorine-containing allyl ether group, styryl group, fluorine-containing styryl group, norbornyl group, fluorine-containing norbornyl group, silyl group, etc. It is done.

  In the present invention, the anion group-containing monomer is preferably a compound represented by the following formula (I).

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり、Ｑ^２は単結合または２価の連結基であり、Ａ⁻はアニオン基であり、Ｍ^＋はスルホニウムまたはヨードニウムカチオンである。］

[Wherein, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, Q ² is a single bond or a divalent linking group, and A ⁻ is an anionic group. And M ⁺ is a sulfonium or iodonium cation. ]

R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms.
The alkyl group having 1 to 5 carbon atoms in R is preferably a linear or branched alkyl group, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group. Tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like.
Examples of the halogenated alkyl group having 1 to 5 carbon atoms in R include groups in which part or all of the hydrogen atoms in the above-mentioned “alkyl group having 1 to 5 carbon atoms in R” are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
Especially, it is preferable that R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 fluorinated alkyl group, and it is a hydrogen atom or a methyl group from industrial availability. It is particularly preferred.

In the formula, the divalent linking group of Q ² is not particularly limited, but a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like are preferable. It is done.
The hydrocarbon group having “substituent” means that part or all of the hydrogen atoms in the hydrocarbon group are substituted with a substituent (a group or atom other than a hydrogen atom).
The hydrocarbon group for Q ² may be an aliphatic hydrocarbon group or an aromatic group. The aliphatic hydrocarbon group and aromatic group in Q ² are the same as the aliphatic hydrocarbon group and aromatic group of W ⁰ .

The hetero atom in the “divalent linking group containing a hetero atom” of Q ² is an atom other than a carbon atom and a hydrogen atom, and examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom.
As the divalent linking group containing a hetero atom, —O—, —C (═O) —O—, —C (═O) —, —O—C (═O) —O—, —C (= O) —NH—, —NH— (H may be substituted with a substituent such as an alkyl group, an acyl group, etc.), —S—, —S (═O) ₂ —, —S (═O) _{2 -O -, - NH-C} (= O) -, = N-, the formula ^{-Y 21 -O-Y 22 -,} - Y 21 -C (= O) -O -, - Y 21 -O- C (═O) —, — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² —, —Y ²¹ —O—C (═O) —Y ²² —, —Y ²¹ —O—Y _{^{22 -O-C (= O)}} -, - Y 21 -O-S (= O) 2 -, - Y 21 -S (= O) 2 -Y 22 -O-S (= O) 2 -, - ^{Y 21 -O-C (= O} ) -Y 22 -O-S (= O) 2 -, - Y 21 -O-Y ^{2 -O-C (= O)} -Y 23 -, - Y 21 -O-S (= O) 2 -Y 22 -, - Y 21 -S-Y 22 -O-S (= O) 2 -Y ²³ -, or ^{-Y 21 -O-C (= O} ) -Y 22 -O-S (= O) 2 -Y 23 - group [wherein represented ^by, Y ^{21, Y 22} and ^{Y 23} are each A divalent hydrocarbon group which may have a substituent independently, O is an oxygen atom, C is a carbon atom, S is a sulfur atom, and m ′ is an integer of 0 to 3. It is. ] Etc. are mentioned.
When Q ² is —NH—, H may be substituted with a substituent such as an alkyl group or an acyl group.
Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group include those similar to the above-mentioned “divalent hydrocarbon group optionally having substituent (s)” (W ⁰ aliphatic hydrocarbon group, aromatic group).
Y ²¹ is preferably an aliphatic hydrocarbon group or an aromatic hydrocarbon group which may have a substituent, more preferably a linear or cyclic alkylene group, and a linear chain having 1 to 5 carbon atoms. An alkylene group is more preferable, and a methylene group or an ethylene group is particularly preferable.
Y ²² is preferably an aliphatic hydrocarbon group or an aromatic hydrocarbon group which may have a substituent, and includes a methylene group, an ethylene group, an alkylmethylene group, a (poly) cycloalkylene group, a phenylene group, or a naphthylene. Groups are more preferred. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
Y ²³ is preferably a linear or branched aliphatic hydrocarbon group which may have a substituent, and a linear or branched alkylene group which may have a substituent. More preferred.
In the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² —, m ′ is an integer of 0 to 3, preferably an integer of 0 to 2, Or 1 is more preferable, and 1 is particularly preferable. That is, the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² — is represented by the formula —Y ²¹ —C (═O) —O—Y ²² —. The group is particularly preferred. Among these, a group represented by the formula — (CH ₂ ) _{a ′} —C (═O) —O— (CH ₂ ) _{b ′} — is preferable. In the formula, a ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, further preferably 1 or 2, and most preferably 1. b ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, more preferably 1 or 2, and most preferably 1.
As the divalent linking group containing a hetero atom, a linear group having an oxygen atom as a hetero atom, for example, a group containing an ether bond or an ester bond, is preferable, and the formula —Y ²¹ —C (═O) — O—, —Y ²¹ —O—C (═O) —, —Y ²¹ —O—Y ²² —, — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² — or —Y ²¹ —. A group represented by O—C (═O) —Y ²² — is more preferable.

Among the above, the divalent linking group for Q ² is particularly a linear or branched alkylene group, a divalent alicyclic hydrocarbon group, or a divalent linking group containing a hetero atom. preferable. Among these, a linear or branched alkylene group or a divalent linking group containing a hetero atom is more preferable.

In the formula, the anion group of A ⁻ is the same as above, and groups represented by the above formulas (an1) to (an4) are preferable.
In the formula, M ⁺ is a sulfonium or iodonium cation, which will be described in detail later.

The anion group-containing monomer is selected from the group consisting of compounds represented by the following formulas (an11) to (an14), (an21) to (an25), (an31) to (an32), (an41) to (an44) At least one selected from the above is preferred.
Among these, as the compounds represented by the following formulas (an11) to (an14), structural units represented by the following formulas (an11-1) to (an13-1) are preferable, respectively.
In the following formulae, M ⁺ is a sulfonium or iodonium cation, respectively. Details of the sulfonium or iodonium cation will be described later.

［式中、Ｒ、Ｑ^２１〜Ｑ^２３、Ｗ^０、Ｒ^ｑ１は前記と同様である。Ｒ^ａｒは置換基を有していてもよい２価の芳香族基である。Ｒ^ｎは水素原子又は炭素数１〜５のアルキル基である。Ｍ^＋はスルホニウム又はヨードニウムカチオンである。］

[Wherein, R, Q ^{21 to} Q ²³ , W ⁰ , R ^q1 are the same as described above. R ^ar is a divalent aromatic group which may have a substituent. R ⁿ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. M ⁺ is a sulfonium or iodonium cation. ]

［式中、Ｒ、Ｒ^ｆ１、Ｒ^ｆ２、ｐ０、、Ｒ^ｎは前記同様であり、Ｑ^２１はそれぞれ独立に単結合又は２価の連結基である。Ｑ^２２は２価の連結基である。Ｑ^２３は−Ｏ−、−ＣＨ_２−Ｏ−、又は−Ｃ（＝Ｏ）−Ｏ−を含有する基である。Ｒ^ｑ１はフッ素原子又はフッ素化アルキル基である。Ｍ^＋はスルホニウム又はヨードニウムカチオンである。］

[Wherein, R, R ^f1 , R ^f2 , p0, and R ⁿ are the same as defined above, and Q ²¹ each independently represents a single bond or a divalent linking group. Q ²² is a divalent linking group. Q ²³ is a group containing —O—, —CH ₂ —O—, or —C (═O) —O—. R ^q1 is a fluorine atom or a fluorinated alkyl group. M ⁺ is a sulfonium or iodonium cation. ]

［式中、Ｒ、Ｑ^２１〜Ｑ^２３、Ｚ^３〜Ｚ^５、Ｒ^６２〜Ｒ^６３、Ｒ^ｎ、Ｒ^ｑ１は前記同様である。ｎ６０は０〜３の整数である。Ｍ^＋はスルホニウム又はヨードニウムカチオンである。］

[Wherein, R, Q ^{21 to} Q ²³ , Z ^{3 to} Z ⁵ , R ^{62 to} R ⁶³ , R ⁿ and R ^q1 are the same as described above. n60 is an integer of 0-3. M ⁺ is a sulfonium or iodonium cation. ]

［式中、Ｒ、Ｚ^１〜Ｚ^２、Ｒ^ｎは前記と同様であり、Ｑ^２４、Ｑ^２５はそれぞれ独立に単結合又は２価の連結基である。Ｍ^＋はスルホニウム又はヨードニウムカチオンである。］

[Wherein, R, Z ^{1 to} Z ² and R ⁿ are the same as defined above, and Q ²⁴ and Q ²⁵ each independently represent a single bond or a divalent linking group. M ⁺ is a sulfonium or iodonium cation. ]

［式中、Ｒ、Ｒ^ｎは前記と同様であり、Ｑ^２６〜Ｑ^２８はそれぞれ独立に単結合又は２価の連結基である。ｎ３０は０〜３の整数である。Ｍ^＋はスルホニウム又はヨードニウムカチオンである。］

[Wherein, R and R ⁿ are as defined above, and Q ^{26 to} Q ²⁸ each independently represent a single bond or a divalent linking group. n30 is an integer of 0-3. M ⁺ is a sulfonium or iodonium cation. ]

In formulas (an11) to (an14), W ⁰ and R ^q1 are the same as described above.
R ^ar is a divalent aromatic group which may have a substituent. Examples of the divalent aromatic group include the same aromatic groups as those described as the divalent hydrocarbon group in the description of the divalent linking group at W ⁰ in the general formula (an1). Especially, the phenylene group which may have a substituent, or the naphthylene group which may have a substituent is preferable.

Q ²¹ is a single bond or a divalent linking group. Examples of the divalent linking group for Q ²¹ include the same divalent linking groups as those for Q ² . Among these, Q ²¹ is preferably a linear or branched alkylene group, a cyclic aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a divalent linking group containing a hetero atom; A branched alkylene group, a combination of a linear or branched alkylene group and a divalent linking group containing a heteroatom, a cyclic aliphatic hydrocarbon group and a divalent linking group containing a heteroatom. A combination or a combination of an aromatic hydrocarbon group and a divalent linking group containing a hetero atom is more preferable; a linear or branched alkylene group, a linear or branched alkylene group and an ester bond [- A combination of C (═O) —O—] with a divalent alicyclic hydrocarbon group and an ester bond [—C (═O) —O—] is particularly preferred; linear or branched An alkylene group of A combination of a branched alkylene group and an ester bond [—C (═O) —O—] is most preferred.

Wherein (AN12), Q ²² represents a divalent linking group, wherein the same as the divalent linking group for Q ^2. Among them, straight-chain or branched mentioned in W ⁰ An alkylene group, a cyclic aliphatic hydrocarbon group, or a divalent aromatic hydrocarbon group is preferable, a linear alkylene group is particularly preferable, and a methylene group or an ethylene group is most preferable.
Wherein (an12), ^{R n} represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. As a C1-C5 alkyl group, the same thing as the C1-C5 alkyl group of said R is mentioned. Of these, R ⁿ is preferably a hydrogen atom or a methyl group.

In formula (an13), Q ²³ represents a group containing —O—, —CH ₂ —O—, or —C (═O) —O—.
Q ²³ is specifically a group consisting of —O—, —CH ₂ —O—, or —C (═O) —O—; —O—, —CH ₂ —O— or —C (═O). And a group composed of —O— and a divalent hydrocarbon group which may have a substituent.
As the divalent hydrocarbon group which may have such a substituent, the same as the divalent hydrocarbon group which may have a substituent described for the divalent linking group in Formula Q ² above. Things.
Q ²³ is preferably a group consisting of —C (═O) —O— and a divalent hydrocarbon group which may have a substituent, and —C (═O) —O— and aliphatic carbonization. A group consisting of a hydrogen group is more preferred, and a group consisting of —C (═O) —O— and a linear or branched alkylene group is more preferred.
Specific examples suitable for Q ^23, in particular, a group represented by the following general formula ^(Q 23 -1).

［式（Ｑ^２３−１）中、Ｒ^ｑ２及びＲ^ｑ３はそれぞれ独立に水素原子、アルキル基又はフッ素化アルキル基であり、互いに結合して環を形成していてもよい。］

[In Formula (Q ²³ -1), R ^q2 and R ^q3 each independently represent a hydrogen atom, an alkyl group, or a fluorinated alkyl group, and may be bonded to each other to form a ring. ]

In the formula (Q ²³ -1), the alkyl group in R ^q2 and R ^q3 may be linear, branched or cyclic, and is preferably linear or branched.
In the case of a linear or branched alkyl group, the number of carbon atoms is preferably 1 to 5, more preferably an ethyl group or a methyl group, and particularly preferably an ethyl group.
In the case of a cyclic alkyl group, the number of carbon atoms is preferably 4 to 15, more preferably 4 to 12, and most preferably 5 to 10. Specific examples include monocycloalkanes; groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as bicycloalkanes, tricycloalkanes, and tetracycloalkanes. More specifically, monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. It is done. Of these, a group in which one or more hydrogen atoms have been removed from adamantane is preferable.

The fluorinated alkyl group for R ^q2 and R ^q3 is a group in which part or all of the hydrogen atoms in the alkyl group are substituted with fluorine atoms.
In the fluorinated alkyl group, the alkyl group not substituted with a fluorine atom may be linear, branched or cyclic, and the same as the above-mentioned “alkyl group in R ^q2 and R ^q3 ”. Can be mentioned.

R ^q2 and R ^q3 may be bonded to each other to form a ring, and the ring formed by R ^q2 and R ^q3 and the carbon atom to which they are bonded includes a monocyclo group in the cyclic alkyl group. The thing remove | excluding two hydrogen atoms from alkane or polycycloalkane can be illustrated, It is preferable that it is a 4-10 membered ring, and it is more preferable that it is a 5-7 membered ring.

Among the above, R ^q2 and R ^q3 are preferably a hydrogen atom or an alkyl group.

In formula (an13), R ^q1 represents a fluorine atom or a fluorinated alkyl group.
In the fluorinated alkyl group for R ^q1 , the alkyl group not substituted with a fluorine atom may be linear, branched or cyclic.
In the case of a linear or branched alkyl group, the number of carbon atoms is preferably 1 to 5, more preferably 1 to 3, and particularly preferably 1 to 2. .
In the case of a cyclic alkyl group, the number of carbon atoms is preferably 4 to 15, more preferably 4 to 12, and still more preferably 5 to 10. Specific examples include monocycloalkanes; groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as bicycloalkanes, tricycloalkanes, and tetracycloalkanes. More specifically, examples include monocycloalkanes such as cyclopentane and cyclohexane; groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. .
In the fluorinated alkyl group, the ratio of the number of fluorine atoms to the total number of fluorine atoms and hydrogen atoms contained in the fluorinated alkyl group (fluorination rate (%)) is preferably 30 to 100%. 50 to 100% is more preferable. The higher the fluorination rate, the higher the hydrophobicity of the resist film.
Among the above, R ^q1 is preferably a fluorine atom.
Wherein ^{(an11-1) ~ (an13-1),} R, Q 21 ~Q 23, R f1, R f2, p0, R n are as defined above.

Wherein ^{(an21) ~ (an25),} R, Q 21 ~Q 23, Z 3 ~Z 5, R 62 ~R 63, R n, R q1 are as defined above.
In formula (an24), n60 is an integer of 0 to 3, and is preferably 0 or 1.

In formulas (an31) to (an32), R, Z ^{1 to} Z ² and R ⁿ are the same as described above, and Q ²⁴ and Q ²⁵ are each independently a single bond or a divalent linking group.
Examples of the divalent linking group for Q ²⁴ and Q ²⁵ include the same divalent linking groups as those described above for Q ² . As described above, if ^{Z 1} is a single ^bond, end which binds to ^{Z 1} of Q ^{24, Q 25} is -C (= O) - is not preferred. The divalent linking group for Q ²⁴ and Q ²⁵ is particularly preferably a linear or branched alkylene group, a cyclic aliphatic hydrocarbon group, or a divalent linking group containing a hetero atom. Among these, a linear or branched alkylene group and a cyclic aliphatic hydrocarbon group are preferable, and a linear alkylene group and a cyclic aliphatic hydrocarbon group are more preferable.

Wherein (an41) ~ (an44), R, R n are as defined ^above, Q 26 ^{to Q 28} represents a single bond or a divalent linking group independently. Q ²⁶ to Q ²⁸ are the same as the ^{Q 24, Q 25.}
In formula (an44), n30 is an integer of 0 to 3, and is preferably 0 or 1.

Specific examples of the monomer having an anion group and a sulfonium or iodonium cation are shown below. In the following formulas, R ^α is a hydrogen atom, a methyl group or a trifluoromethyl group, and M ⁺ is the same as described above.

(Sulfonium or iodonium cation)
The anion group-containing monomer has a sulfonium or iodonium cation that becomes a counter cation (M ⁺ in the above formula) of the anion group as described above.
The first sulfonium or iodonium cation (sulfonium or iodonium cation possessed by the anion group-containing monomer) is the second sulfonium or iodonium cation (cation possessed by the salt exchange compound) used for salt exchange in the step (ii). It has low hydrophobicity. Such a first sulfonium or iodonium cation is not particularly limited, and can be appropriately determined according to the hydrophobicity of the second sulfonium or iodonium cation.
As the first sulfonium or iodonium cation, for example, a cation represented by the following general formula (c-1) or (c-2) can be used.

［式中、Ｒ^１”〜Ｒ^３”はそれぞれ独立に置換基を有していてもよいアリール基、アルキル基、又はアルケニル基を表す。Ｒ^１”〜Ｒ^３”のうち、いずれか二つが相互に結合して式中のイオウ原子と共に環を形成してもよい。Ｒ^５”〜Ｒ^６”はそれぞれ独立に置換基を有していてもよいアリール基、アルキル基又はアルケニル基を表す。］

[Wherein, R ¹ ″ to R ³ ″ each independently represents an aryl group, an alkyl group, or an alkenyl group which may have a substituent. Any two of R ¹ ″ to R ³ ″ may be bonded to each other to form a ring together with the sulfur atom in the formula. R ⁵ ″ to R ⁶ ″ each independently represents an aryl group, alkyl group or alkenyl group which may have a substituent. ]

In the formula (c-1), R ¹ ″ to R ³ ″ each independently represents an aryl group, an alkyl group or an alkenyl group which may have a substituent. Any two of R ¹ ″ to R ³ ″ may be bonded to each other to form a ring together with the sulfur atom in the formula.
Further, when blended in resist compositions, since the lithography properties and resist pattern shape is further improved, among the R 1 ^"to R ^3", it is preferable that at least one is an aryl group, R 1 ^"to R ^{3 "of,} more preferably more than two are aryl groups, R 1 ^'and particularly preferably all to R ^3" are aryl groups.

As the aryl group for R ¹ ″ to R ³ ″, an unsubstituted aryl group having 6 to 20 carbon atoms; some or all of the hydrogen atoms of the unsubstituted aryl group are alkyl groups, alkoxy groups, halogen atoms, hydroxyl groups , An oxo group (═O), an aryl group, an alkoxyalkyloxy group, an alkoxycarbonylalkyloxy group, —C (═O) —O—R ⁶ ′, —O—C (═O) —R ⁷ ′, —O And a substituted aryl group substituted with —R ⁸ ′ and the like. R ⁶ ′, R ⁷ ′ and R ⁸ ′ are each a linear, branched or cyclic saturated hydrocarbon group having 1 to 25 carbon atoms, or a C 2 to 5 carbon atoms. It is a linear or branched aliphatic unsaturated hydrocarbon group.
In R ¹ ″ to R ³ ″, the unsubstituted aryl group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at a low cost. Specific examples include a phenyl group and a naphthyl group.
The alkyl group as a substituent in the substituted aryl group of R ¹ ″ to R ³ ″ is preferably an alkyl group having 1 to 5 carbon atoms, and is a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. Most preferably.
As the alkoxy group as a substituent in the substituted aryl group, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. Most preferably it is.
The halogen atom as a substituent in the substituted aryl group is preferably a fluorine atom.
Examples of the aryl group as a substituent in the substituted aryl group include the same aryl groups as those described above for R ¹ ″ to R ³ ″, preferably an aryl group having 6 to 20 carbon atoms, and an aryl group having 6 to 10 carbon atoms. Group is more preferable, and phenyl group and naphthyl group are more preferable.

As the alkoxyalkyloxy group in the substituted aryl group, for example,
General formula: -O-C ( ^R47 ) ( ^R48 ) -O- ^R49
[Wherein, R ⁴⁷ and R ⁴⁸ each independently represent a hydrogen atom or a linear or branched alkyl group, and R ⁴⁹ represents an alkyl group. ] Is represented.
In R ⁴⁷ and R ⁴⁸ , the alkyl group preferably has 1 to 5 carbon atoms, may be linear or branched, and is preferably an ethyl group or a methyl group, and most preferably a methyl group.
At least one of R ⁴⁷ and R ⁴⁸ is preferably a hydrogen atom. In particular, it is more preferable that one is a hydrogen atom and the other is a hydrogen atom or a methyl group.
The alkyl group for R ⁴⁹ preferably has 1 to 15 carbon atoms and may be linear, branched or cyclic.
The linear or branched alkyl group for R ⁴⁹ preferably has 1 to 5 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group. Can be mentioned.
The cyclic alkyl group for R ⁴⁹ preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, a monocycloalkane, bicycloalkane, tricycloalkane, tetracycloalkane, etc., which may or may not be substituted with an alkyl group having 1 to 5 carbon atoms, a fluorine atom or a fluorinated alkyl group, etc. And a group obtained by removing one or more hydrogen atoms from the polycycloalkane. Examples of the monocycloalkane include cyclopentane and cyclohexane. Examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.

As the alkoxycarbonylalkyloxy group in the substituted aryl group, for example,
General formula: —O—R ⁵⁰ —C (═O) —O—R ⁵⁶
[Wherein, R ⁵⁰ represents a linear or branched alkylene group, and R ⁵⁶ represents a tertiary alkyl group. ] Is represented.
The linear or branched alkylene group for R ⁵⁰ preferably has 1 to 5 carbon atoms, such as a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, or a 1,1-dimethylethylene group. Etc.
As the tertiary alkyl group for R ⁵⁶ , 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, 1-methyl-1-cyclopentyl group, 1-ethyl-1-cyclopentyl group, 1-methyl -1-cyclohexyl group, 1-ethyl-1-cyclohexyl group, 1- (1-adamantyl) -1-methylethyl group, 1- (1-adamantyl) -1-methylpropyl group, 1- (1-adamantyl) -1-methylbutyl group, 1- (1-adamantyl) -1-methylpentyl group; 1- (1-cyclopentyl) -1-methylethyl group, 1- (1-cyclopentyl) -1-methylpropyl group, 1- (1-cyclopentyl) -1-methylbutyl group, 1- (1-cyclopentyl) -1-methylpentyl group; 1- (1-cyclohexyl) -1-methylethyl Group, 1- (1-cyclohexyl) -1-methylpropyl group, 1- (1-cyclohexyl) -1-methylbutyl group, 1- (1-cyclohexyl) -1-methylpentyl group, tert-butyl group, tert -Pentyl group, tert-hexyl group and the like.
Moreover, the general ^formula: the ^{R 56} in the -O-R 50 -C (= O ) -O-R 56, also include groups replaced by ^{R 56} '. R ⁵⁶ ′ is a hydrogen atom, an alkyl group, a fluorinated alkyl group, or an aliphatic cyclic group that may contain a hetero atom.
^Examples of the alkyl group for R ⁵⁶ ′ include the same alkyl groups as those described above for R ⁴⁹ .
^Examples of the fluorinated alkyl group for R ⁵⁶ ′ include groups in which some or all of the hydrogen atoms within the alkyl group for R ⁴⁹ have been substituted with fluorine atoms.
Examples of the aliphatic cyclic group which may contain a hetero atom in R ⁵⁶ ′ include an aliphatic cyclic group containing no hetero atom, an aliphatic cyclic group containing a hetero atom in the ring structure, and an aliphatic cyclic group. Examples include those in which a hydrogen atom in the group is substituted with a heteroatom.
Regarding R ⁵⁶ ′, the aliphatic cyclic group containing no hetero atom includes a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, tetracycloalkane, and the like. Can be mentioned. Examples of the monocycloalkane include cyclopentane and cyclohexane. Examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.
As for R ⁵⁶ ′, specific examples of the aliphatic cyclic group containing a hetero atom in the ring structure include formulas (L1) to (L6) and (S1) exemplified in the description of the component (B) described later. ) To (S4) and the like.
As for R ⁵⁶ ′, the hydrogen atom in the aliphatic cyclic group is specifically substituted with a hetero atom, specifically, the hydrogen atom in the aliphatic cyclic group is substituted with an oxygen atom (═O), etc. Is mentioned.

^{-C (= O) -O-R} 6 ', -O-C (= O) -R 7', 'R 6 ^{in' -O-R 8, R 7} ', R 8' are each carbon atoms 1 to 25 linear, branched or cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a linear or branched aliphatic unsaturated hydrocarbon group having 2 to 5 carbon atoms. .
The linear or branched saturated hydrocarbon group has 1 to 25 carbon atoms, preferably 1 to 15 carbon atoms, and more preferably 4 to 10 carbon atoms.
Examples of the linear saturated hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group.
Examples of the branched saturated hydrocarbon group excluding the tertiary alkyl group include, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3 -Methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like can be mentioned.
The linear or branched saturated hydrocarbon group may have a substituent. Examples of the substituent include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (═O), a cyano group, and a carboxy group.
As the alkoxy group as a substituent of the linear or branched saturated hydrocarbon group, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, An n-butoxy group and a tert-butoxy group are preferable, and a methoxy group and an ethoxy group are most preferable.
Examples of the halogen atom as a substituent of the linear or branched saturated hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
As the halogenated alkyl group as a substituent of the linear or branched saturated hydrocarbon group, part or all of the hydrogen atoms of the linear or branched saturated hydrocarbon group are the halogen atoms. And a group substituted with.
The cyclic saturated hydrocarbon group having 3 to 20 carbon atoms in R ⁶ ′, R ⁷ ′, and R ⁸ ′ may be either a polycyclic group or a monocyclic group. A group in which one hydrogen atom has been removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, and the like. More specifically, one hydrogen atom was removed from a monocycloalkane such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane, and a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Group and the like.
The cyclic saturated hydrocarbon group may have a substituent. For example, part of the carbon atoms constituting the ring of the cyclic alkyl group may be substituted with a heteroatom, or the hydrogen atom bonded to the ring of the cyclic alkyl group may be substituted with a substituent. Good.
Examples of the former include one or more hydrogen atoms from a heterocycloalkane in which a part of the carbon atoms constituting the ring of the monocycloalkane or polycycloalkane is substituted with a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Examples include groups other than atoms. The ring structure may have an ester bond (—C (═O) —O—). Specifically, a lactone-containing monocyclic group such as a group obtained by removing one hydrogen atom from γ-butyrolactone, or a group obtained by removing one hydrogen atom from a bicycloalkane, tricycloalkane, or tetracycloalkane having a lactone ring. And other lactone-containing polycyclic groups.
Examples of the substituent in the latter example include the same as those described above as the substituent that the linear or branched alkyl group may have, a lower alkyl group, and the like.
R ⁶ ′, R ⁷ ′, and R ⁸ ′ may be a combination of a linear or branched alkyl group and a cyclic alkyl group.
A combination of a linear or branched alkyl group and a cyclic alkyl group includes a group in which a cyclic alkyl group is bonded as a substituent to a linear or branched alkyl group, and a substituent to the cyclic alkyl group. And a group having a linear or branched alkyl group bonded thereto.
Examples of the linear aliphatic unsaturated hydrocarbon group for R ⁶ ′, R ⁷ ′, and R ⁸ ′ include a vinyl group, a propenyl group (allyl group), and a butynyl group.
Examples of the branched aliphatic unsaturated hydrocarbon group for R ⁶ ′, R ⁷ ′, and R ⁸ ′ include a 1-methylpropenyl group and a 2-methylpropenyl group.
The linear or branched aliphatic unsaturated hydrocarbon group may have a substituent. Examples of the substituent include the same ones as those exemplified as the substituent which the linear or branched alkyl group may have.
Among R ⁷ ′ and R ⁸ ′, among them, the lithography characteristics and the resist pattern shape are good, so that the linear or branched saturated hydrocarbon group having 1 to 15 carbon atoms, or the carbon number 3-20 cyclic saturated hydrocarbon groups are preferred.

The aryl groups for R ¹ ″ to R ³ ″ are each preferably a phenyl group or a naphthyl group.

Examples of the alkyl group for R ¹ ″ to R ³ ″ include a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms. Especially, it is preferable that it is C1-C5 from the point which is excellent in resolution. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a nonyl group, and a decyl group. A methyl group is preferable because it is excellent in resolution and can be synthesized at low cost.

As an alkenyl group of R < ¹ >"-R< ³ >", it is preferable that it is C2-C10, for example, 2-5 are more preferable, and 2-4 are more preferable. Specific examples include a vinyl group, a propenyl group (allyl group), a butynyl group, a 1-methylpropenyl group, and a 2-methylpropenyl group.

When any two of R ¹ ″ to R ³ ″ are bonded to each other to form a ring together with the sulfur atom in the formula, it is preferable that a 3 to 10 membered ring including the sulfur atom is formed, It is particularly preferable to form a 5- to 7-membered ring.
When any two of R ¹ ″ to R ³ ″ are bonded to each other to form a ring together with the sulfur atom in the formula, the remaining one is preferably an aryl group. Examples of the aryl group include the same aryl groups as those described above for R ¹ ″ to R ³ ″.

  Specific examples of the cation moiety in the compound represented by the formula (c-1) include, for example, triphenylsulfonium, (3,5-dimethylphenyl) diphenylsulfonium, (4- (2-adamantoxymethyloxy)- 3,5-dimethylphenyl) diphenylsulfonium, (4- (2-adamantoxymethyloxy) phenyl) diphenylsulfonium, (4- (tert-butoxycarbonylmethyloxy) phenyl) diphenylsulfonium, (4- (tert-butoxycarbonyl) Methyloxy) -3,5-dimethylphenyl) diphenylsulfonium, (4- (2-methyl-2-adamantyloxycarbonylmethyloxy) phenyl) diphenylsulfonium, (4- (2-methyl-2-adamantyloxycarbonylmethyl) Xy) -3,5-dimethylphenyl) diphenylsulfonium, tri (4-methylphenyl) sulfonium, dimethyl (4-hydroxynaphthyl) sulfonium, monophenyldimethylsulfonium, diphenylmonomethylsulfonium, (4-methylphenyl) diphenylsulfonium, 4-methoxyphenyl) diphenylsulfonium, tri (4-tert-butyl) phenylsulfonium, diphenyl (1- (4-methoxy) naphthyl) sulfonium, di (1-naphthyl) phenylsulfonium, 1-phenyltetrahydrothiophenium, 1 -(4-Methylphenyl) tetrahydrothiophenium, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium, 1- (4-methoxynaphthalen-1-yl) Trahydrothiophenium, 1- (4-ethoxynaphthalen-1-yl) tetrahydrothiophenium, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium, 1-phenyltetrahydrothiopyranium, Examples include 1- (4-hydroxyphenyl) tetrahydrothiopyranium, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiopyranium, 1- (4-methylphenyl) tetrahydrothiopyranium, and the like.

  In addition, specific examples of the cation represented by the formula (c-1) include those shown below.

［式中、ｇ１は繰返し数を示し、１〜５の整数である。］

[Wherein g1 represents the number of repetitions and is an integer of 1 to 5. ]

［式中、ｇ２、ｇ３は繰返し数を示し、ｇ２は０〜２０の整数であり、ｇ３は０〜２０の整数である。］

[Wherein g2 and g3 represent the number of repetitions, g2 is an integer of 0 to 20, and g3 is an integer of 0 to 20. ]

In formula (c-2), R ⁵ ″ to R ⁶ ″ each independently represents an aryl group, alkyl group or alkenyl group which may have a substituent.
At least one of R ⁵ ″ to R ⁶ ″ represents an aryl group. Any of R ⁵ ″ to R ⁶ ″ is preferably an aryl group.
As the aryl group for R ⁵ ″ to R ⁶ ″, the same as the aryl groups for R ¹ ″ to R ³ ″ can be used.
Examples of the alkyl group for R ⁵ ″ to R ⁶ ″ include the same as the alkyl group for R ¹ ″ to R ³ ″.
Examples of the alkenyl group for R ⁵ ″ to R ⁶ ″ include the same alkenyl groups for R ¹ ″ to R ³ ″.
Among these, it is most preferable that all of R ⁵ ″ to R ⁶ ″ are phenyl groups.
Specific examples of the cation moiety represented by the formula (c-2) include diphenyliodonium and bis (4-tert-butylphenyl) iodonium.

  In addition, preferred examples of the cation represented by (c-1) include compounds represented by the following formulas (c-1-01) to (c-2-04).

In formulas (c-1-01) to (c-1-04), u is an integer of 1 to 3, and 1 or 2 is most preferable.
In formulas (c-1-01) to (c-1-04), R ^{6a to} R ^8a are an alkylene group which may have a substituent or a phenylene group which may have a substituent, R ^{6b to} R ^8b are a hydrogen atom, an alkyl group which may have a substituent, a phenyl group which may have a substituent, or a naphthyl group.
In formula (c-1-04), R ⁹ represents an alkyl group which may have a substituent, a phenyl group which may have a substituent, or a naphthyl group.

The alkylene group for R ^{6a to} R ^8a is preferably a linear or branched alkylene group. 1-12 are preferable, as for carbon number of this alkylene group, 1-5 are more preferable, 1-3 are more preferable, and 1 or 2 is especially preferable.
Examples of the substituent that the alkylene group may have include an alkoxy group, a halogen atom, a hydroxyl group, an oxo group (═O), a cyano group, an aryl group, an alkoxyalkyloxy group, an alkoxycarbonylalkyloxy group, —C ( ═O) —O—R ⁷ ″, —O—C (═O) —R ⁸ ″, —O—R ⁹ ″ and the like. Alkoxy group, halogen atom, aryl group, alkoxyalkyloxy group, alkoxycarbonyl As the alkyloxy group, —C (═O) —O—R ⁷ ″, —O—C (═O) —R ⁸ ″, —O—R ⁹ ″, R ¹ in the above formula (c-1) is used. In the description of “˜R ³ ”, the same as those described as the substituent that the substituted aryl group may have.
In the formula, as the alkyl group which may have a substituent in R ^{6b to} R ^8b and R ^9, the substituted alkyl exemplified in the description of R ¹ ″ to R ³ ″ in the general formula (c-1) The same thing as a group is mentioned.
Examples of the substituent that the phenyl group or naphthyl group in R ^{6b to} R ^8b and R ⁹ may have include the substituted aryl described in the description of R ¹ ″ to R ³ ″ in the general formula (c-1). The thing similar to what was mentioned as a substituent which group may have is mentioned.
Preferable examples of the cations represented by the above formulas (c-1-01) to (c-1-04) include those shown below. In the formula, R ^C represents a substituent (alkoxy group, alkoxyalkyloxy group, alkoxycarbonylalkyloxy group, halogen atom, hydroxyl group, oxo group (═O), aryl group exemplified in the description of the substituted aryl group. , —C (═O) —O—R ⁶ ′, —O—C (═O) —R ⁷ ′, —O—R ⁸ ′).
Specific examples are shown below.

  Moreover, the cation represented by the following general formula (c-3) or general formula (c-4) is also mentioned.

［式中、Ｒ^４０は水素原子またはアルキル基であり、Ｒ^４１はアルキル基、アセチル基、カルボキシ基、またはヒドロキシアルキル基であり、Ｒ^４２〜Ｒ^４６はそれぞれ独立してアルキル基、アセチル基、アルコキシ基、カルボキシ基、またはヒドロキシアルキル基であり；ｎ_０〜ｎ_５はそれぞれ独立して０〜３の整数であり、ただし、ｎ_０＋ｎ_１は５以下であり、ｎ_６は０〜２の整数である。］

[Wherein, R ⁴⁰ represents a hydrogen atom or an alkyl group, R ⁴¹ represents an alkyl group, an acetyl group, a carboxy group, or a hydroxyalkyl group, and R ^{42 to} R ⁴⁶ each independently represents an alkyl group, an acetyl group, An alkoxy group, a carboxy group, or a hydroxyalkyl group; n _{0 to} n ₅ are each independently an integer of 0 to 3, provided that n ₀ + n ₁ is 5 or less and n ₆ is 0 to 2 It is an integer. ]

In general formula (c-3), the alkyl group of R ⁴⁰ is preferably an alkyl group having 1 to 15 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, and still more preferably an alkyl group having 4 to 10 carbon atoms. Of these, a linear or branched alkyl group is particularly preferred.
In R ^{41 to} R ⁴⁶ in the general formula (c-3) or (c-4), the alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a linear or branched alkyl group. A methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, or a tert-butyl group is particularly preferable.
The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a linear or branched alkoxy group, and particularly preferably a methoxy group or an ethoxy group.
The hydroxyalkyl group is preferably a group in which one or more hydrogen atoms in the alkyl group are substituted with a hydroxy group, and examples thereof include a hydroxymethyl group, a hydroxyethyl group, and a hydroxypropyl group.
When the code n ₀ attached to the OR ⁴⁰ is an integer of 2 or more, the plurality of OR ⁴⁰ may be the same or different.
When the symbols n _{1 to} n ₆ attached to R ^{41 to} R ⁴⁶ are integers of 2 or more, the plurality of R ^{41 to} R ⁴⁶ may be the same or different.
n ₀ is preferably 0 or 1.
n ₁ is preferably 0-2.
n ₂ and n ₃ are preferably each independently 0 or 1, more preferably 0.
n ₄ is preferably 0 to 2, more preferably 0 or 1.
n ₅ is preferably 0 or 1, more preferably 0.
n ₆ is preferably 0 or 1.

  As a suitable thing of the cation represented by the said Formula (c-3) or Formula (c-4), what is shown below is mentioned.

The first sulfonium or iodonium cation in the present invention preferably has not only low hydrophobicity but also high stability during polymerization as compared with the second sulfonium or iodonium cation.
Examples of the cationic skeleton having high stability include a triphenylsulfonium skeleton, a diphenyliodonium skeleton, a trimethylsulfonium skeleton, and a dimethylphenylsulfonium skeleton.

[Salt exchange compound]
The salt exchange compound is a compound having a sulfonium or iodonium cation (“second sulfonium or iodonium cation”), and the second sulfonium or iodonium cation possessed by the salt exchange compound by salt exchange in step (ii). And the sulfonium or iodonium cation in the precursor polymer synthesized by the step (i) are capable of salt exchange. That is, the second sulfonium or iodonium cation possessed by the compound for salt exchange becomes a cation possessed by the polymer compound produced by the production method of the present invention.
In the present invention, the compound for salt exchange is preferably a compound composed of a cation moiety comprising a second sulfonium or iodonium cation and an anion moiety comprising a non-nucleophilic ion.

(Second sulfonium or iodonium cation)
The second sulfonium or iodonium cation is a cation having higher hydrophobicity than the first sulfonium or iodonium cation. The salt exchange in step (ii) is a salt exchange from a low hydrophobic cation to a highly hydrophobic cation, whereby the salt exchange reaction can proceed well and a polymer compound having a desired cation can be produced. it can.

  Examples of the second sulfonium or iodonium cation (second cation) include those similar to the cation exemplified in the first sulfonium or iodonium cation (first cation), and the hydrophobicity of the first sulfonium or iodonium cation. It can be appropriately determined according to the degree of nature.

  In the present invention, the first cation and the second cation are required to have a certain difference in retention time in the measurement by the HPLC method described above. The value when divided by the retention time of one cation is 1.05 or more, preferably 1.1 or more. By setting it as 1.05 or more, a salt exchange reaction becomes easy.

Specific examples of the combination of the “first sulfonium or iodonium cation” (first cation) and the “second sulfonium or iodonium cation” (second cation) preferred in the present invention include the following combinations. It is done.
The first cation is a cation represented by the formula (c-1-1); the second cation is the formula (c-1-01) to (c-1-02), (c-1 -03-2), a cation represented by (c-1-8) or (c-1-31), or a combination which is a bis (4-tert-butylphenyl) iodonium cation.
The first cation is a diphenyliodonium cation; the second cation is (c-1-1) to (c-1-31), (c-1-01) to (c-1-04) combination.
The first cation is a trimethylsulfonium cation or a cation represented by (c-1-33); the second cation is (c-1-1) to (c-1-31), (c-1 −01) to (c-1-04).

(Non-nucleophilic ion)
Examples of non-nucleophilic ions include halogen ions such as bromine ions and chlorine ions; ions that can be acids with lower acidity than the precursor polymer, BF ₄ ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , PF ₆ ⁻ or And ClO ₄ ^{— and the} like. The ion that can be an acid having a lower acidity than the precursor polymer is not particularly limited and can be appropriately determined according to the type of monomer used in the precursor polymer. For example, p-toluenesulfonic acid Examples thereof include sulfonate ions such as ions, methanesulfonate ions, and benzenesulfonate ions.

[Polymer compound]
The polymer compound produced by the method for producing a polymer compound according to the present invention has a structural unit that decomposes upon exposure to generate an acid (hereinafter, this structural unit is also referred to as “structural unit (a0)”). Is.
The present inventors paid attention to the difficulty in synthesizing a polymer compound when a monomer containing some acid-generating groups was used as a raw material, and that this was caused by instability of a cation in the monomer. Newly found. Therefore, in the production method of the present invention, instead of the cation that the structural unit (a0) should have, a precursor polymer is used in advance using a monomer having a cation that is (structurally) stable and less hydrophobic than the cation. Then, a production method in which salt exchange is performed on a desired cation having high hydrophobicity was adopted.
According to this production method, a polymer compound having a specific cation that has been difficult to synthesize directly can be produced easily and in high yield.
In addition, according to this method, since various types of cations can be introduced into the polymer compound, the degree of freedom in selecting the cation species in the polymer compound is increased, and the composition of the resist composition using the polymer compound is optimized. Therefore, it is possible to contribute to improvement of lithography characteristics.

Further, in this production method, a polymer compound having a small content of an anion group-containing monomer and a monomer group composed of a monomer in which the anion group-containing monomer is salt-exchanged with the second sulfonium or iodonium cation is produced. That is, in the production method of the present invention, the residual monomer at the time of synthesis and the monomer remaining after the cation in the residual monomer is salt-exchanged are reduced.
This is considered to be because the monomer having a low hydrophobic cation facilitates removal of the monomer even when a residual monomer is generated after synthesis.

  Specifically, according to the present invention, the residual amount of the anion group-containing monomer in the precursor polymer (the polymer compound before salt exchange) obtained in the step (i) is the precursor before the salt exchange. The polymer compound is preferably 500 ppm (mass basis) or less, more preferably 250 ppm (mass basis) or less, and further preferably less than 100 ppm (mass basis) with respect to the polymer. The smaller the residual amount of the monomer in the precursor polymer (polymer compound before salt exchange) obtained in the step (i), the better. In addition, it is possible to reduce the residual monomer amount by performing the above-described washing after the synthesis and before the salt exchange. The remaining anion group-containing monomer is also salt-exchanged together with salt exchange for the precursor polymer in the step (ii). For this reason, the remaining amount of the monomer group consisting of the anion group-containing monomer and the monomer obtained by salt exchange of the anion group-containing monomer with the second sulfonium or iodonium cation with respect to the polymer compound after salt exchange is The residual concentration of the anionic group-containing monomer with respect to the polymer compound is substantially the same or lower. Therefore, the residual amount of the monomer group is preferably 500 ppm (mass basis) or less, more preferably 250 ppm (mass basis) or less with respect to the polymer compound produced by the production method of the present invention. It is more preferable that the amount is less than 100 ppm (mass basis).

  As described above, when the content of the monomer group is small, the resist composition containing the polymer compound produced by the production method of the present invention has an exposure margin, roughness reduction, and the like when the resist composition is used. Lithography characteristics and resist pattern shape become better.

  In addition to the structural unit (a0), the polymer compound produced by the production method of the present invention may further have other structural units. Examples of other structural units include structural units (a1) to (a4) described later. The polymer compound having other structural units can be produced by using a monomer that derives each structural unit together with an anion group-containing monomer.

≪Resist composition≫
The resist composition of the present invention is a polymer compound produced by the method for producing a polymer compound of the present invention, that is, a polymer having a structural unit (structural unit (a0)) that decomposes upon exposure to generate an acid. A compound.
The resist composition of the present invention preferably contains a base component (A) (hereinafter referred to as “component (A)”) whose solubility in a developer is changed by the action of an acid. When a resist film is formed using such a resist composition and the resist film is selectively exposed, an acid is generated from the structural unit (a0) in the exposed portion, and the action of the acid (A ) While the solubility of the component in the developer changes, the solubility of the component (A) in the developer does not change in the unexposed area, so the solubility in the developer between the exposed and unexposed areas There is a difference. For this reason, when the resist film is developed, when the resist composition is positive, the exposed portion is dissolved and removed to form a positive resist pattern. When the resist composition is negative, the unexposed portion is formed. A negative resist pattern is formed by dissolution and removal.
In this specification, a resist composition in which an exposed portion is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and an unexposed portion is dissolved and removed to form a negative resist pattern. Is referred to as a negative resist composition.
The resist composition of the present invention may be a positive resist composition or a negative resist composition.
In addition, the resist composition of the present invention may be used for an alkali development process using an alkali developer for development processing at the time of forming a resist pattern, and a developer (organic developer) containing an organic solvent is used for the development processing. It may be for the solvent development process used.

<(A) component>
As the component (A), organic compounds that are usually used as base material components for chemically amplified resists can be used singly or in combination of two or more.
Here, the “base material component” is an organic compound having a film forming ability, and an organic compound having a molecular weight of 500 or more is preferably used. When the molecular weight of the organic compound is 500 or more, the film-forming ability is improved and a nano-level resist pattern is easily formed.
“Organic compounds having a molecular weight of 500 or more” used as the base component are roughly classified into non-polymers and polymers.
As the non-polymer, those having a molecular weight of 500 or more and less than 4000 are usually used. Hereinafter, the “low molecular compound” refers to a non-polymer having a molecular weight of 500 or more and less than 4000.
As the polymer, those having a molecular weight of 1000 or more are usually used. In the present specification and claims, the term “resin” refers to a polymer having a molecular weight of 1000 or more.
As the molecular weight of the polymer, a polystyrene-reduced mass average molecular weight by GPC (gel permeation chromatography) is used.
Component (A) may have increased solubility in a developer due to the action of an acid, or may decrease solubility in a developer due to the action of an acid.

When the resist composition of the present invention is a resist composition that forms a negative resist pattern in an alkali development process (or forms a positive resist pattern in a solvent development process), the component (A) is preferably A base material component (hereinafter, also referred to as (A0 ′) component) that is soluble in an alkali developer is used, and a crosslinking agent component is further blended. As the alkali-soluble base component, a resin (alkali-soluble resin) is usually used. In such a resist composition, when an acid is generated from the structural unit (a0) by exposure, the acid acts to cause crosslinking between the component (A0 ′) and the crosslinking agent component, resulting in solubility in an alkaline developer. Decreases (the solubility in an organic developer increases). Therefore, in the formation of a resist pattern, when a resist film obtained by coating the resist composition on a support is selectively exposed, the exposed portion is hardly soluble in an alkali developer (to an organic developer). On the other hand, the unexposed area remains soluble (almost insoluble in the organic developer) while remaining undissolved in the alkali developer, so that a negative resist pattern can be formed by developing with an alkali developer. . At this time, if an organic developer is used as the developer, a positive resist pattern can be formed.
As the component (A0 ′), a known resin can be used as a resin that is soluble in an alkali developer (hereinafter referred to as “alkali-soluble resin”).
Examples of the alkali-soluble resin include α- (hydroxyalkyl) acrylic acid or α- (hydroxyalkyl) acrylic acid alkyl ester (preferably having 1 to 5 carbon atoms) disclosed in, for example, JP-A-2000-206694. Resin having a unit derived from at least one selected from alkyl ester); disclosed in US Pat. No. 6,949,325, an atom other than a hydrogen atom or a substituent is bonded to the α-position carbon atom having a sulfonamide group Acrylic resin or polycycloolefin resin which may be used; containing a fluorinated alcohol disclosed in US Pat. An atom other than a hydrogen atom or a substituent may be bonded to the carbon atom. Acrylic resin; disclosed in Japanese 2006-259582 discloses, polycycloolefin resins having fluorinated alcohol, with minimal swelling can formation of a satisfactory resist pattern.
In addition, the α- (hydroxyalkyl) acrylic acid is an α-position carbon atom to which a carboxy group is bonded among acrylic acids in which an atom other than a hydrogen atom or a substituent may be bonded to the α-position carbon atom. One or both of acrylic acid to which a hydrogen atom is bonded and α-hydroxyalkyl acrylic acid in which a hydroxyalkyl group (preferably a hydroxyalkyl group having 1 to 5 carbon atoms) is bonded to the α-position carbon atom Show.
As the crosslinking agent component, for example, it is usually preferable to use an amino crosslinking agent such as glycoluril having a methylol group or an alkoxymethyl group, a melamine crosslinking agent, or the like because a good resist pattern with less swelling can be formed. It is preferable that the compounding quantity of a crosslinking agent component is 1-50 mass parts with respect to 100 mass parts of alkali-soluble resin.

When the resist composition of the present invention is a resist composition that forms a positive pattern in an alkali development process and forms a negative pattern in a solvent development process, the component (A) is preferably an action of an acid. A substrate component (A0) (hereinafter referred to as “(A0) component”) having an increased polarity is used. Since the polarity of the component (A0) changes before and after exposure, good development contrast can be obtained not only in the alkali development process but also in the solvent development process.
That is, when the alkali development process is applied, the component (A0) is hardly soluble in an alkali developer before exposure, and when acid is generated from the structural unit (a0) by exposure, the polarity of the component is reduced by the action of the acid. Increases the solubility in an alkaline developer. Therefore, in the formation of a resist pattern, when a resist film obtained by applying the resist composition on a support is selectively exposed, the exposed portion changes from slightly soluble to soluble in an alkaline developer. Since the unexposed portion remains hardly soluble in alkali and does not change, a positive pattern can be formed by alkali development.
On the other hand, when applying the solvent development process, the component (A0) is highly soluble in an organic developer before exposure, and when an acid is generated from the structural unit (a0) by exposure, The polarity becomes higher and the solubility in an organic developer decreases. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the resist composition on the support is selectively exposed, the exposed portion changes from soluble to poorly soluble in an organic developer. On the other hand, since the unexposed portion remains soluble and does not change, by developing with an organic developer, a contrast can be provided between the exposed portion and the unexposed portion, and a negative pattern can be formed.

In the present invention, the component (A) is preferably the component (A0). That is, the resist composition of the present invention is preferably a chemically amplified resist composition that becomes positive in the alkali development process and negative in the solvent development process.
The component (A0) may be a resin component whose polarity is increased by the action of an acid, a low molecular compound component whose polarity is increased by the action of an acid, or a mixture thereof. .
The component (A0) is preferably a resin component that increases in polarity by the action of an acid. In particular, the polymer compound (A1) that generates an acid by exposure and increases in polarity by the action of an acid (hereinafter referred to as “A0”) What contains "(A1) component") is preferable.

[(A1) component]
Specifically, the component (A1) is a high component having a structural unit (a0) that decomposes upon exposure to generate an acid and a structural unit (a1) that includes an acid-decomposable group that increases in polarity by the action of an acid. Molecular compounds are preferred, and polymer compounds produced by the polymer compound production method of the first aspect are particularly preferred.

(Structural unit (a0))
The structural unit (a0) is a structural unit that decomposes upon exposure to generate an acid, and is a structural unit derived from the above-described anion group-containing monomer, the cation portion of which is the second sulfonium or iodonium cation. It is a structural unit that has undergone salt exchange.
The structural unit (a0) is a structural unit obtained by cleaving the ethylenic double bond in the monomer represented by the above formula (I) into a single bond, the cation portion of which is the second sulfonium or A structural unit that is salt-exchanged with an iodonium cation is preferred. Specifically, a structural unit represented by the following formula (a0-1) is preferable.

［式中、Ｒ、Ｑ^２、Ａ⁻は前記同様であり、Ｍ’^＋は上述した第二のスルホニウム又はヨードニウムカチオンである。］

[Wherein, R, Q ² and A ⁻ are the same as defined above, and M ′ ⁺ represents the second sulfonium or iodonium cation described above. ]

  Specifically, as the structural unit (a0), from the compounds represented by the above formulas (an11) to (an14), (an21) to (an25), (an31) to (an32), (an41) to (an44) Particularly preferred is a structural unit derived from at least one compound selected from the group consisting of cation moieties salt-exchanged with the second sulfonium or iodonium cation.

In the component (A1), as the structural unit (a0), one type of structural unit may be used, or two or more types may be used in combination.
In the component (A1), the proportion of the structural unit (a0) is preferably 1 to 40 mol%, more preferably 1 to 35 mol%, based on the total of all the structural units constituting the component (A1). 3-30 mol% is more preferable. When the proportion of the structural unit (a0) is not less than the lower limit of the above range, a pattern can be easily obtained when the resist composition is obtained, and the lithography properties are further improved. On the other hand, by being below the upper limit value, it is possible to balance with other structural units.

(Structural unit (a1))
The structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity is increased by the action of an acid.
The “acid-decomposable group” is an acid-decomposable group capable of cleaving at least part of the bond in the structure of the acid-decomposable group by the action of an acid generated from the component (A1) (structural unit (a0)) upon exposure. It is group which has.
Examples of the acid-decomposable group whose polarity increases by the action of an acid include a group that decomposes by the action of an acid to generate a polar group.
Examples of the polar group include a carboxy group, a hydroxyl group, an amino group, a sulfo group (—SO ₃ H), and the like. Among these, a polar group containing —OH in the structure (hereinafter sometimes referred to as “OH-containing polar group”) is preferable, a carboxy group or a hydroxyl group is preferable, and a carboxy group is particularly preferable.
More specifically, examples of the acid-decomposable group include a group in which the polar group is protected with an acid-dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected with an acid-dissociable group).
The “acid-dissociable group” means that at least between the acid-dissociable group and an atom adjacent to the acid-dissociable group by the action of an acid generated from the component (A1) (structural unit (a0)) upon exposure. It is a group having acid dissociation properties that can cleave the bond. The acid-dissociable group constituting the acid-decomposable group must be a group having a lower polarity than the polar group generated by dissociation of the acid-dissociable group. Is dissociated, a polar group having a polarity higher than that of the acid dissociable group is generated to increase the polarity. As a result, the polarity of the entire component (A1) increases. As the polarity increases, the solubility in the developer changes relatively. When the developer is an alkaline developer, the solubility increases. On the other hand, the developer contains an organic solvent (organic type). In the case of a developer, the solubility decreases.

The acid-dissociable group is not particularly limited, and those that have been proposed as acid-dissociable groups for base resins for chemically amplified resists can be used. In general, a group that forms a cyclic or chain tertiary alkyl ester with a carboxy group in (meth) acrylic acid or the like, an acetal type acid dissociable group such as an alkoxyalkyl group, and the like are widely known.
Here, the “tertiary alkyl ester” is an ester formed by replacing a hydrogen atom of a carboxy group with a chain or cyclic alkyl group, and the carbonyloxy group (—C (═O The structure in which the tertiary carbon atom of the chain or cyclic alkyl group is bonded to the terminal oxygen atom of) -O-). In this tertiary alkyl ester, when an acid acts, a bond is cut between an oxygen atom and a tertiary carbon atom to form a carboxy group.
The chain or cyclic alkyl group may have a substituent.
Hereinafter, a group that is acid dissociable by constituting a carboxy group and a tertiary alkyl ester is referred to as a “tertiary alkyl ester type acid dissociable group” for convenience.

Examples of the tertiary alkyl ester type acid dissociable group include an aliphatic branched acid dissociable group and an acid dissociable group containing an aliphatic cyclic group.
Here, “aliphatic branched” means having a branched structure having no aromaticity. The structure of the “aliphatic branched acid dissociable group” is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The “hydrocarbon group” may be either saturated or unsaturated, but is usually preferably saturated.
Examples of the aliphatic branched acid dissociable group include a group represented by —C (R ⁷¹ ) (R ⁷² ) (R ⁷³ ). ^Wherein, R 71 ^{to R 73} each independently represents a linear alkyl group of 1 to 5 carbon atoms. The group represented by —C (R ⁷¹ ) (R ⁷² ) (R ⁷³ ) preferably has 4 to 8 carbon atoms, specifically a tert-butyl group or a 2-methyl-2-butyl group. , 2-methyl-2-pentyl group, 3-methyl-3-pentyl group and the like. A tert-butyl group is particularly preferable.

The “aliphatic cyclic group” means a monocyclic group or a polycyclic group having no aromaticity.
The aliphatic cyclic group in the “acid-dissociable group containing an aliphatic cyclic group” may or may not have a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, and an oxygen atom (= O).
The basic ring structure excluding the substituent of the aliphatic cyclic group is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The hydrocarbon group may be either saturated or unsaturated, but is usually preferably saturated.
The aliphatic cyclic group may be monocyclic or polycyclic.
As the aliphatic cyclic group, those having 3 to 30 carbon atoms are preferable, those having 5 to 30 are more preferable, 5 to 20 are more preferable, 6 to 15 are particularly preferable, and 6 to 12 is most preferable. . As the monocyclic aliphatic cyclic group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclobutane, cyclopentane, and cyclohexane. The polycyclic aliphatic cyclic group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like. Moreover, a part of carbon atoms constituting the ring of these aliphatic cyclic groups may be substituted with an ether group (—O—).

Examples of the acid dissociable group containing an aliphatic cyclic group include:
(I) a substituent on a carbon atom bonded to an atom (for example, —O— in —C (═O) —O—) adjacent to the acid dissociable group on the ring skeleton of the monovalent aliphatic cyclic group A group in which (atom or group other than hydrogen atom) is bonded to form a tertiary carbon atom;
(Ii) a group having a monovalent aliphatic cyclic group and a branched alkylene having a tertiary carbon atom bonded thereto.
In the group (i), examples of the substituent bonded to the carbon atom bonded to the atom adjacent to the acid dissociable group on the ring skeleton of the aliphatic cyclic group include an alkyl group. Examples of the alkyl group include those similar to R ¹⁴ in formulas (1-1) to (1-9) described later.
Specific examples of the group (i) include groups represented by the following general formulas (1-1) to (1-9).
Specific examples of the group (ii) include groups represented by the following general formulas (2-1) to (2-6).

［式中、Ｒ^１４はアルキル基であり、ｇは０〜８の整数である。］

[Wherein, R ¹⁴ represents an alkyl group, and g represents an integer of 0 to 8. ]

［式中、Ｒ^１５およびＲ^１６は、それぞれ独立してアルキル基である。］

[Wherein, R ¹⁵ and R ¹⁶ each independently represents an alkyl group. ]

In formulas (1-1) to (1-9), the alkyl group of R ¹⁴ may be linear, branched or cyclic, and is preferably linear or branched.
The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4, and still more preferably 1 or 2. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group, or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.
The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specific examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group and the like, and isopropyl group is most preferable.
The cyclic alkyl group preferably has 3 to 20 carbon atoms, and more preferably 4 to 12 carbon atoms. Specific examples thereof include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. A part of carbon atoms constituting the ring of the cyclic alkyl group may be substituted with an etheric oxygen atom (—O—).
g is preferably an integer of 0 to 3, more preferably an integer of 1 to 3, and still more preferably 1 or 2.
In formulas (2-1) to (2-6), examples of the alkyl group for R ^{15 to} R ¹⁶ include the same alkyl groups as those described above for R ¹⁴ .
In the formulas (1-1) to (1-9) and (2-1) to (2-6), a part of the carbon atoms constituting the ring is substituted with an etheric oxygen atom (—O—). May be.
In formulas (1-1) to (1-9) and (2-1) to (2-6), a hydrogen atom bonded to a carbon atom constituting the ring may be substituted with a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, a fluorine atom, and a fluorinated alkyl group.

The “acetal-type acid dissociable group” is generally bonded to an oxygen atom by substituting a hydrogen atom at the terminal of an OH-containing polar group such as a carboxy group or a hydroxyl group. When an acid is generated by exposure, this acid acts to break the bond between the acetal type acid dissociable group and the oxygen atom to which the acetal type acid dissociable group is bonded. OH-containing polar groups are formed.
Examples of the acetal type acid dissociable group include a group represented by the following general formula (p1).

［式中、Ｒ^１’，Ｒ^２’はそれぞれ独立して水素原子または炭素数１〜５のアルキル基を表し、ｎは０〜３の整数を表し、Ｙは炭素数１〜５のアルキル基または脂肪族環式基を表す。］

[Wherein, R ¹ 'and R ² ' each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, n represents an integer of 0 to 3, and Y represents an alkyl group having 1 to 5 carbon atoms. Or represents an aliphatic cyclic group. ]

In formula (p1), n is preferably an integer of 0 to 2, more preferably 0 or 1, and most preferably 0.
Examples of the alkyl group for R ¹ ′ and R ² ′ include the same alkyl groups as those described above for the substituent that may be bonded to the carbon atom at the α-position in the description of the α-substituted acrylate ester. A methyl group or an ethyl group is preferred, and a methyl group is most preferred.
In the present invention, it is preferable that at least one of R ¹ ′ and R ² ′ is a hydrogen atom. That is, the acid dissociable group (p1) is preferably a group represented by the following general formula (p1-1).

［式中、Ｒ^１’、ｎ、Ｙは上記と同じである。］

[Wherein R ¹ ′, n and Y are the same as described above. ]

Examples of the alkyl group for Y include the same alkyl groups as those described above for the substituent that may be bonded to the α-position carbon atom in the description of the α-substituted acrylate ester described later.
The aliphatic cyclic group for Y can be appropriately selected from monocyclic or polycyclic aliphatic cyclic groups that have been proposed in a number of conventional ArF resists. For example, the above “aliphatic ring” Examples thereof are the same as the aliphatic cyclic groups mentioned in “Acid-dissociable groups containing formula groups”.

  Examples of the acetal type acid dissociable group also include a group represented by the following general formula (p2).

［式中、Ｒ^１７、Ｒ^１８はそれぞれ独立して直鎖状若しくは分岐鎖状のアルキル基または水素原子であり；Ｒ^１９は直鎖状、分岐鎖状若しくは環状のアルキル基である。または、Ｒ^１７およびＲ^１９がそれぞれ独立に直鎖状若しくは分岐鎖状のアルキレン基であって、Ｒ^１７とＲ^１９とが結合して環を形成していてもよい。］

[Wherein, R ¹⁷ and R ¹⁸ each independently represents a linear or branched alkyl group or a hydrogen atom; and R ¹⁹ represents a linear, branched or cyclic alkyl group. Alternatively, R ¹⁷ and R ¹⁹ may each independently be a linear or branched alkylene group, and R ¹⁷ and R ¹⁹ may be bonded to form a ring. ]

In R ¹⁷ and R ¹⁸ , the alkyl group preferably has 1 to 15 carbon atoms, may be linear or branched, and is preferably an ethyl group or a methyl group, and most preferably a methyl group.
In particular, it is preferable that one of R ¹⁷ and R ¹⁸ is a hydrogen atom and the other is a methyl group.
R ¹⁹ is a linear, branched or cyclic alkyl group, preferably having 1 to 15 carbon atoms, and may be any of linear, branched or cyclic.
When R ¹⁹ is linear or branched, it preferably has 1 to 5 carbon atoms, more preferably an ethyl group or a methyl group, and most preferably an ethyl group.
When R ¹⁹ is cyclic, it preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, one or more polycycloalkanes such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane, which may or may not be substituted with a fluorine atom or a fluorinated alkyl group. Examples similar to the above “aliphatic cyclic group”, such as a group excluding the hydrogen atom, can be exemplified. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.
In the formula (p2), R ¹⁷ and R ¹⁹ are each independently a linear or branched alkylene group (preferably an alkylene group having 1 to 5 carbon atoms), and R ¹⁹ and R ¹⁷ And may be combined.
In this case, a cyclic group is formed by R ¹⁷ , R ¹⁹ , the oxygen atom to which R ¹⁹ is bonded, and the carbon atom to which the oxygen atom and R ¹⁷ are bonded. The cyclic group is preferably a 4- to 7-membered ring, and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

  The structural unit (a1) is not particularly limited as long as it has an acid-decomposable group, but an acrylic group in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. A structural unit derived from an acid ester and comprising a structural unit (a11) containing an acid-decomposable group, a hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and hydrogen bonded to a benzene ring A structural unit in which a hydrogen atom of a hydroxyl group of a structural unit derived from hydroxystyrene which may be substituted with a substituent other than a hydroxyl group is substituted with an acid-dissociable group or a substituent containing an acid-dissociable group ( a12), a hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, and a hydrogen atom bonded to the naphthalene ring may be substituted with a substituent other than a hydroxyl group (hydroxynaphtho Structural units hydroxyl hydrogen atoms of constituent units derived from alkylene) is replaced by a substituent containing an acid-dissociable group or an acid-dissociable group (a13), and the like.

Here, in the present specification and claims, the “structural unit derived from an acrylate ester” means a structural unit formed by cleavage of an ethylenic double bond of an acrylate ester.
“Acrylic acid ester” is a compound in which the hydrogen atom at the carboxy group terminal of acrylic acid (CH ₂ ═CH—COOH) is substituted with an organic group.
An “organic group” is a group containing a carbon atom and has an atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (fluorine atom, chlorine atom, etc.)). Also good.
In the acrylate ester, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. The substituent that replaces the hydrogen atom bonded to the α-position carbon atom is an atom or group other than a hydrogen atom, such as an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, or carbon. Examples thereof include hydroxyalkyl groups of 1 to 5. The α-position carbon atom of the acrylate ester is a carbon atom to which a carbonyl group is bonded unless otherwise specified.
Hereinafter, an acrylate ester in which a hydrogen atom bonded to a carbon atom at the α-position is substituted with a substituent may be referred to as an α-substituted acrylate ester. Further, the acrylate ester and the α-substituted acrylate ester may be collectively referred to as “(α-substituted) acrylate ester”.
In the α-substituted acrylate ester, the alkyl group as a substituent at the α-position is preferably a linear or branched alkyl group, specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, n- Examples thereof include a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.
Specific examples of the halogenated alkyl group as the substituent at the α-position include groups in which part or all of the hydrogen atoms of the above-mentioned “alkyl group as the substituent at the α-position” are substituted with a halogen atom. It is done. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
Specific examples of the hydroxyalkyl group as the substituent at the α-position include groups in which part or all of the hydrogen atoms of the above-mentioned “alkyl group as the substituent at the α-position” are substituted with a hydroxy group. .
Bonded to the α-position of the α-substituted acrylate ester is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, and a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. An alkyl group or a fluorinated alkyl group having 1 to 5 carbon atoms is more preferred, and a hydrogen atom or a methyl group is most preferred from the viewpoint of industrial availability.

“A structural unit derived from hydroxystyrene or a hydroxystyrene derivative” means a structural unit formed by cleavage of an ethylenic double bond of hydroxystyrene or a hydroxystyrene derivative.
“Hydroxystyrene derivative” is a concept including those in which the hydrogen atom at the α-position of hydroxystyrene is substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. The α-position (α-position carbon atom) means a carbon atom to which a benzene ring is bonded unless otherwise specified.
The “structural unit derived from vinyl benzoic acid or a vinyl benzoic acid derivative” means a structural unit configured by cleavage of an ethylenic double bond of vinyl benzoic acid or a vinyl benzoic acid derivative.
The “vinyl benzoic acid derivative” is a concept including a compound in which the hydrogen atom at the α-position of vinyl benzoic acid is substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. The α-position (α-position carbon atom) means a carbon atom to which a benzene ring is bonded unless otherwise specified.
An “organic group” is a group containing a carbon atom and has an atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (fluorine atom, chlorine atom, etc.)). Also good.
Hereinafter, the structural unit (a11), the structural unit (a12), and the structural unit (a13) will be described.

[Structural unit (a11)]
Specific examples of the structural unit (a11) include structural units represented by general formula (a11-0-1) shown below, structural units represented by general formula (a11-0-2) shown below, and the like. .

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり；Ｘ^１は酸解離性基であり；Ｙ^２は２価の連結基であり；Ｘ^２は酸解離性基である。］

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms; X ¹ is an acid dissociable group; Y ² is a divalent linking group. Yes; X ² is an acid-dissociable group. ]

In the general formula (a11-0-1), the alkyl group and the halogenated alkyl group of R are each exemplified as the substituent which may be bonded to the α-position carbon atom in the description of the α-substituted acrylate ester. And the same alkyl groups and halogenated alkyl groups. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms, and most preferably a hydrogen atom or a methyl group.
X ¹ is not particularly limited as long as it is an acid dissociable group, and examples thereof include the above-described tertiary alkyl ester type acid dissociable groups, acetal type acid dissociable groups, and the like. An ester type acid dissociable group is preferred.
In general formula (a11-0-2), R is the same as defined above.
X ² is the same as X ¹ in formula (a11-0-1).

Examples of the divalent linking group of Y ^2, but are not limited to, divalent hydrocarbon group which may have a substituent group, and a divalent linking group containing a hetero atom as preferred.
Substituted divalent hydrocarbon group which may have a divalent linking group containing a hetero atom, which may have a substituent exemplified as the divalent linking group of the Q ² 2 This is the same as a divalent hydrocarbon group and a divalent linking group containing a hetero atom.

Among the above, as the divalent linking group for Y ² , in particular, a linear or branched alkylene group, a divalent alicyclic hydrocarbon group, or a divalent linking group containing a hetero atom is included. preferable. Among these, a linear or branched alkylene group or a divalent linking group containing a hetero atom is preferable.

  More specifically, examples of the structural unit (a11) include structural units represented by general formulas (a1-1) to (a1-4) shown below.

［式中、Ｒ、Ｒ^１’、Ｒ^２’、ｎ、ＹおよびＹ^２はそれぞれ前記と同じであり、Ｘ’は第３級アルキルエステル型酸解離性基を表す。］’

[Wherein, R, R ¹ ′, R ² ′, n, Y and Y ² are the same as defined above, and X ′ represents a tertiary alkyl ester-type acid dissociable group. ] '

In the formula, X ′ is the same as the tertiary alkyl ester-type acid dissociable group.
^{R 1 ', R 2',} n, as the Y, respectively, ^{R 1} in the general formula listed in the description of "acetal-type acid dissociable group" described above ^{(p1) ', R 2'} , n, similarly to the Y Can be mentioned.
The Y ^2, the same groups as those described above for ^{Y 2} in the above general formula (a11-0-2).
Specific examples of the structural units represented by the general formulas (a1-1) to (a1-4) are shown below.
In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

In the present invention, as the structural unit (a11), a structural unit represented by the following general formula (a11-0-11), a structural unit represented by the following general formula (a11-0-12), and the following general formula ( a11-0-13), a structural unit represented by the following general formula (a11-0-14), a structural unit represented by the following general formula (a11-0-15), and the following general unit It is preferable to have at least one selected from the group consisting of structural units represented by formula (a11-0-2).
Among them, the structural unit represented by the following general formula (a11-0-11), the structural unit represented by the following general formula (a11-0-12), and the following general formula (a11-0-13) A structural unit represented by the following general formula (a11-0-14) and at least one selected from the group consisting of the structural unit represented by the following general formula (a11-0-15) It is more preferable.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり、Ｒ^２１はアルキル基であり；Ｒ^２２は、当該Ｒ^２２が結合した炭素原子と共に脂肪族単環式基を形成する基であり；Ｒ^２３は分岐鎖状のアルキル基であり；Ｒ^２４は、当該Ｒ^２４が結合した炭素原子と共に脂肪族多環式基を形成する基であり；Ｒ^２５は炭素数１〜５の直鎖状のアルキル基である。Ｒ^１５およびＲ^１６は、それぞれ独立してアルキル基である。Ｙ^２は２価の連結基であり、Ｘ^２は酸解離性基である。］

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, R ²¹ is an alkyl group; R ²² is a carbon to which R ²² is bonded. A group that forms an aliphatic monocyclic group together with an atom; R ²³ is a branched alkyl group; and R ²⁴ is a group that forms an aliphatic polycyclic group together with the carbon atom to which R ²⁴ is bonded. R ²⁵ is a linear alkyl group having 1 to 5 carbon atoms. R ¹⁵ and R ¹⁶ are each independently an alkyl group. Y ² is a divalent linking group, and X ² is an acid dissociable group. ]

In each formula, the description of R, Y ² and X ² is the same as described above.
In formula (a11-0-11), examples of the alkyl group for R ²¹ include the same alkyl groups as those described above for R ¹⁴ in formulas (1-1) to (1-9). Group or isopropyl group is preferred.
R ²² is, the aliphatic monocyclic group formed together with the carbon atom to which R ²² is bonded, the same aliphatic cyclic groups as those in the aforementioned tertiary alkyl ester-type acid dissociable groups, a monocyclic group The thing similar to that is mentioned. Specific examples include groups in which one or more hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane is preferably a 3- to 11-membered ring, more preferably a 3- to 8-membered ring, further preferably a 4- to 6-membered ring, and particularly preferably a 5- or 6-membered ring.
In the monocycloalkane, a part of carbon atoms constituting the ring may or may not be substituted with an ether group (—O—).
Moreover, this monocycloalkane may have a C1-C5 alkyl group, a fluorine atom, or a C1-C5 fluorinated alkyl group as a substituent.
Examples of R ²² constituting such an aliphatic monocyclic group include a linear alkylene group in which an ether group (—O—) may be interposed between carbon atoms.

Specific examples of the structural unit represented by the formula (a11-0-11) include the formulas (a1-1-16) to (a1-1-23), (a1-1-27), and (a1-1 -31). Among these, the formulas (a1-1-16) to (a1-1-17), (a1-1-20) to (a1-1-23), (a1-1-27), (a1-1-1- The structural unit represented by the following (a11-1-02) including the structural units represented by 31), (a1-1-32), and (a1-1-33) is preferable. Moreover, the structural unit represented by the following (a11-1-02 ′) is also preferable.
In each formula, h is an integer of 1 to 4, and 1 or 2 is preferable.

［式中、Ｒ、Ｒ^２１はそれぞれ前記と同じであり、ｈは１〜４の整数である。］

[Wherein, R and R ²¹ are the same as defined above, and h is an integer of 1 to 4, respectively. ]

Wherein ^(A11-0-12), as the branched alkyl group for ^{R 23,} alkyl of the formula (1-1) to (1-9) branched chain mentioned by an alkyl group ^{R 14} in Examples thereof are the same as those described above, and an isopropyl group is most preferable.
R ²⁴ is, the aliphatic polycyclic group formed together with the carbon atom to which R ²⁴ is bonded, the same aliphatic cyclic groups as those in the aforementioned tertiary alkyl ester-type acid dissociable group, polycyclic group The thing similar to what is is mentioned.
Specific examples of the structural unit represented by the formula (a11-0-12) include those represented by the formulas (a1-1-26) and (a1-1-28) to (a1-1-30). Units are listed.
The constitutional unit represented by formula ^{(a11-0-12), R 24} is preferably the aliphatic polycyclic group which forms together with the carbon atom to which ^{R 24} is bonded is a 2-adamantyl group, especially The structural unit represented by the formula (a1-1-26) is preferable.

In formula (a11-0-13), R and R ²⁴ are the same as defined above.
Examples of the linear alkyl group for R ²⁵ include the same linear alkyl groups as those described above for the alkyl group for R ^{14 in} the formulas (1-1) to (1-9), and methyl Most preferred are groups or ethyl groups.
Specific examples of the structural unit represented by the formula (a11-0-13) include formulas (a1-1-1) to (a1-1-2) exemplified as specific examples of the general formula (a1-1). ), Structural units represented by (a1-1-7) to (a1-1-15).
The constitutional unit represented by formula ^{(a11-0-13), R 24} is preferably the aliphatic polycyclic group which forms together with the carbon atom to which ^{R 24} is bonded is a 2-adamantyl group, especially The structural unit represented by the formula (a1-1-1) or (a1-1-2) is preferable. Further, R ²⁴ is also preferably the aliphatic polycyclic group which forms together with the carbon atom to which R ²⁴ is bonded is a "group obtained by removing one or more hydrogen atoms from tetracyclododecane", the formula (a1 The structural unit represented by (-1-8), (a1-1-9) or (a1-1-30) is also preferable.

In formula (a11-0-14), R and R ²² are the same as defined above. R ¹⁵ and ^{R 16} are the same as ^{R 15} and ^{R 16} in each of the general formulas (2-1) to (2-6).
Specific examples of the structural unit represented by the formula (a11-0-14) include the formulas (a1-1-35) and (a1-1-36) exemplified as specific examples of the general formula (a1-1). ).

In formula (a11-0-15), R and R ²⁴ are the same as defined above. R ¹⁵ and ^{R 16} are the same as ^{R 15} and ^{R 16} in each of the general formulas (2-1) to (2-6).
Specific examples of the structural unit represented by the formula (a11-0-15) include formulas (a1-1-4) to (a1-1-6) exemplified as specific examples of the general formula (a1-1). ) And (a1-1-34).

Examples of the structural unit represented by the formula (a11-0-2) include the structural unit represented by the formula (a1-3) or (a1-4), particularly represented by the formula (a1-3). Are preferred.
As the structural unit represented by the formula (a11-0-2), in particular, Y ^{2 in} the formula is —Y ²¹ —O—Y ²² — or —Y ²¹ —C (═O) —O—Y ^22. Those represented by-are preferred.
Preferred examples of the structural unit include a structural unit represented by the following general formula (a1-3-01); a structural unit represented by the following general formula (a1-3-02); 3-03) and the like.

［式中、Ｒは前記と同じであり、Ｒ^１３は水素原子またはメチル基であり、Ｒ^１４はアルキル基であり、ｅは１〜１０の整数であり、ｎ’は０〜３の整数である。］

[Wherein, R is the same as above, R ¹³ is a hydrogen atom or a methyl group, R ¹⁴ is an alkyl group, e is an integer of 1 to 10, and n ′ is an integer of 0 to 3] is there. ]

［式中、Ｒは前記と同じであり、Ｙ^２’およびＹ^２”はそれぞれ独立して２価の連結基であり、Ｘ’は酸解離性基であり、ｗは０〜３の整数である。］

[Wherein, R is as defined above, Y ² ′ and Y ² ″ are each independently a divalent linking group, X ′ is an acid-dissociable group, and w is an integer of 0 to 3] is there.]

In formulas (a1-3-01) to (a1-3-02), R ¹³ is preferably a hydrogen atom.
R ¹⁴ is the same as ^{R 14} in the formula (1-1) to (1-9).
e is preferably an integer of 1 to 8, more preferably an integer of 1 to 5, and most preferably 1 or 2.
n ′ is preferably 1 or 2, and most preferably 2.
Specific examples of the structural unit represented by the formula (a1-3-01) include structural units represented by the formulas (a1-3-25) to (a1-3-26).
Specific examples of the structural unit represented by the formula (a1-3-02) include structural units represented by the formulas (a1-3-27) to (a1-3-28).

In formula (a1-3-03), examples of the divalent linking group for Y ² ′ and Y ² ″ include the same groups as those described above for Q ² in formula (I).
Y ² ′ is preferably a divalent hydrocarbon group which may have a substituent, more preferably a linear aliphatic hydrocarbon group, and even more preferably a linear alkylene group. Among these, a linear alkylene group having 1 to 5 carbon atoms is preferable, and a methylene group and an ethylene group are most preferable.
Y ² ″ is preferably a divalent hydrocarbon group which may have a substituent, more preferably a linear aliphatic hydrocarbon group, and still more preferably a linear alkylene group. A linear alkylene group of 1 to 5 is preferable, and a methylene group and an ethylene group are most preferable.
Examples of the acid dissociable group in X ′ include the same groups as described above, and are preferably tertiary alkyl ester-type acid dissociable groups, and the ring skeleton of the above-described (i) monovalent aliphatic cyclic group In addition, a group in which a substituent is bonded to a carbon atom bonded to an atom adjacent to the acid dissociable group to form a tertiary carbon atom is more preferable, and among them, the group represented by the general formula (1-1) is preferable. Preferred are the groups
w is an integer of 0 to 3, and w is preferably an integer of 0 to 2, more preferably 0 or 1, and most preferably 1.
As the structural unit represented by the formula (a1-3-03), a structural unit represented by the following general formula (a1-3-03-1) or (a1-3-03-2) is preferable. The structural unit represented by the formula (a1-3-03-1) is preferable.

［式中、ＲおよびＲ^１４はそれぞれ前記と同じであり、ａ’は１〜１０の整数であり、ｂ’は１〜１０の整数であり、ｔは０〜３の整数である。］

[Wherein, R and R ¹⁴ are the same as defined above, a ′ is an integer of 1 to 10, b ′ is an integer of 1 to 10, and t is an integer of 0 to 3, respectively. ]

In formulas (a1-3-03-1) to (a1-3-03-2), a ′ is the same as described above, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, and 1 or 2 is particularly preferred.
b ′ is the same as described above, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, and particularly preferably 1 or 2.
t is preferably an integer of 1 to 3, and 1 or 2 is particularly preferable.
Specific examples of the structural unit represented by formula (a1-3-03-1) or (a1-3-03-2) include those represented by formulas (a1-3-29) to (a1-3-32). The structural unit represented is mentioned.

[Structural unit (a12)]
In the structural unit (a12), a hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, and a hydrogen atom bonded to the benzene ring may be substituted with a substituent other than a hydroxyl group. It is a structural unit in which a hydrogen atom of a hydroxyl group of a structural unit derived from styrene is substituted with an acid dissociable group or a substituent containing an acid dissociable group.
“Hydroxystyrene” is a compound in which one vinyl group and at least one hydroxyl group are bonded to a benzene ring. 1-3 are preferable and, as for the number of the hydroxyl groups couple | bonded with a benzene ring, 1 is especially preferable. The bonding position of the hydroxyl group in the benzene ring is not particularly limited. When the number of hydroxyl groups is one, the para position of the bonding position of the vinyl group is preferable. When the number of hydroxyl groups is an integer of 2 or more, any bonding position can be combined.
Examples of the acid dissociable group for substituting the hydrogen atom of the hydroxyl group include the same groups as those described above, preferably a tertiary alkyl ester type acid dissociable group or an acetal type acid dissociable group, and an acetal type acid dissociable group is More preferred.
Examples of the substituent containing an acid dissociable group include a group composed of an acid dissociable group and a divalent linking group. Examples of the divalent linking group include those similar to the divalent linking group for Q ² in the formula (I), and a group in which the terminal structure on the acid dissociable group side is a carbonyloxy group is particularly preferable. . In this case, it is preferable that an acid dissociable group is bonded to the oxygen atom (—O—) of the carbonyloxy group.
Examples of the substituent containing an acid dissociable group include a group represented by R ¹¹ ′ —O—C (═O) — and a group represented by R ¹¹ ′ —O—C (═O) —R ¹² ′ —. Is preferred. In the formula, R ¹¹ ′ is an acid dissociable group, and R ¹² ′ is a linear or branched alkylene group.
The acid dissociable group for R ¹¹ ′ is preferably a tertiary alkyl ester type acid dissociable group or an acetal type acid dissociable group, more preferably a tertiary alkyl ester type acid dissociable group. As a preferable example of the tertiary alkyl ester type acid dissociable group, the aliphatic branched acid dissociable group represented by the above-described —C (R ⁷¹ ) (R ⁷² ) (R ⁷³ ), the formula (1- Examples include groups represented by 1) to (1-9), groups represented by formulas (2-1) to (2-6), and the like.
Examples of the alkylene group for R ¹² ′ include a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, and a 1,1-dimethylethylene group. R ¹² ′ is preferably a linear alkylene group.

[Structural unit (a13)]
In the structural unit (a13), a hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, and a hydrogen atom bonded to the naphthalene ring may be substituted with a substituent other than a hydroxyl group. (Hydroxynaphthalene) (hereinafter referred to as (α-substituted) vinyl (hydroxynaphthalene)) is a structural unit obtained by substituting a hydrogen atom of a hydroxyl group of a structural unit with an acid-dissociable group or a substituent containing an acid-dissociable group. is there.
“Vinyl (hydroxynaphthalene)” is a compound in which one vinyl group and at least one hydroxyl group are bonded to a naphthalene ring. The vinyl group may be bonded to the 1-position of the naphthalene ring or may be bonded to the 2-position. 1-3 are preferable and, as for the number of the hydroxyl groups couple | bonded with a naphthalene ring, 1 is especially preferable. The bonding position of the hydroxyl group in the naphthalene ring is not particularly limited. In the case where a vinyl group is bonded to the 1-position or 2-position of the naphthalene ring, any one of the 5- to 8-positions of the naphthalene ring is preferable. In particular, when the number of hydroxyl groups is one, any one of 5 to 7 positions of the naphthalene ring is preferable, and 5 or 6 positions are preferable. When the number of hydroxyl groups is an integer of 2 or more, any bonding position can be combined.

  In the structural unit (a13), examples of the acid dissociable group for substituting a hydrogen atom of a hydroxyl group and the substituent containing an acid dissociable group include the same groups as those described above for the structural unit (a12). It is done.

As the structural unit (a1) contained in the component (A1), 1 type of structural unit may be used, or 2 or more types may be used.
In the component (A1), the proportion of the structural unit (a1) is preferably from 15 to 70 mol%, more preferably from 15 to 60 mol%, more preferably from 20 to 55 mol%, based on all structural units constituting the component (A1). Is more preferable. By setting it to the lower limit value or more, a pattern can be easily obtained when a resist composition is formed, and lithography properties such as sensitivity, resolution, and pattern shape are improved. Moreover, the balance with another structural unit can be taken by making it below an upper limit.

(Structural unit (a2))
The component (A1) preferably further has a structural unit (a2) containing a —SO ₂ — containing cyclic group or a lactone-containing cyclic group in addition to the structural units (a0) and (a1).
The —SO ₂ — containing cyclic group or lactone cyclic group of the structural unit (a2) is effective for enhancing the adhesion of the resist film to the substrate when the component (A1) is used for forming the resist film. Is. Moreover, it is effective in the alkali development process in that the affinity with a developer containing water such as an alkali developer is improved.
In addition, when the structural unit (a0) or (a1) includes a —SO ₂ — containing cyclic group or a lactone-containing cyclic group in the structure, the structural unit also corresponds to the structural unit (a2). Such a structural unit corresponds to the structural unit (a0) or (a1) and does not correspond to the structural unit (a2).

Here, the “—SO ₂ -containing cyclic group” refers to a cyclic group containing a ring containing —SO ₂ — in the ring skeleton, specifically, a sulfur atom in —SO ₂ — ( S) is a cyclic group that forms part of the ring skeleton of the cyclic group. The ring containing —SO ₂ — in the ring skeleton is counted as the first ring, and when it is only the ring, it is a monocyclic group, and when it has another ring structure, it is a polycyclic group regardless of the structure. Called. The —SO ₂ — containing cyclic group may be monocyclic or polycyclic.
-SO ₂ - containing cyclic group, in particular, -O-SO ₂ - within the ring skeleton cyclic group containing, i.e. -O-SO ₂ - -O-S- medium is a part of the ring skeleton It is preferably a cyclic group containing a sultone ring to be formed.
The —SO ₂ — containing cyclic group preferably has 3 to 30 carbon atoms, more preferably 4 to 20 carbon atoms, still more preferably 4 to 15 carbon atoms, and particularly preferably 4 to 12 carbon atoms. preferable. However, the carbon number is the number of carbon atoms constituting the ring skeleton, and does not include the carbon number in the substituent.
The —SO ₂ — containing cyclic group may be an —SO ₂ — containing aliphatic cyclic group or an —SO ₂ — containing aromatic cyclic group. Preferably -SO ₂ - containing aliphatic cyclic group.
The —SO ₂ -containing aliphatic cyclic group includes at least a hydrogen atom from an aliphatic hydrocarbon ring in which a part of carbon atoms constituting the ring skeleton is substituted with —SO ₂ — or —O—SO ₂ —. One group is excluded. More specifically, a group obtained by removing at least one hydrogen atom from an aliphatic hydrocarbon ring in which —CH ₂ — constituting the ring skeleton is substituted with —SO ₂ —, —CH ₂ — constituting the ring And a group obtained by removing at least one hydrogen atom from an aliphatic hydrocarbon ring in which CH ₂ — is substituted with —O—SO ₂ —.
The alicyclic hydrocarbon ring preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon ring may be polycyclic or monocyclic. The monocyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms are removed from a monocycloalkane having 3 to 6 carbon atoms. Examples of the monocycloalkane include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon ring, a group in which two hydrogen atoms are removed from a polycycloalkane having 7 to 12 carbon atoms is preferable. Specific examples of the polycycloalkane include adamantane, norbornane, isobornane. , Tricyclodecane, tetracyclododecane and the like.

The —SO ₂ — containing cyclic group may have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (═O), —COOR ″, —OC (═O) R ″, a hydroxyalkyl group, a cyano group, and the like. Is mentioned.
The alkyl group as the substituent is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and a hexyl group. Among these, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, the group couple | bonded with the oxygen atom (-O-) to the alkyl group quoted as the alkyl group as the said substituent is mentioned.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group for the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.
Examples of the halogenated alkyl group as the substituent include a group in which part or all of the hydrogen atoms of the alkyl group mentioned as the alkyl group as the substituent are substituted with the halogen atom. As the halogenated alkyl group, a fluorinated alkyl group is preferable, and a perfluoroalkyl group is particularly preferable.
R ″ in —COOR ″ and —OC (═O) R ″ is a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms.
When R ″ is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably a methyl group or an ethyl group. preferable.
When R ″ is a cyclic alkyl group, it preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, a fluorine atom Alternatively, one or more hydrogen atoms are removed from a polycycloalkane such as a monocycloalkane, bicycloalkane, tricycloalkane, or tetracycloalkane, which may or may not be substituted with a fluorinated alkyl group. More specifically, one or more hydrogen atoms are removed from a monocycloalkane such as cyclopentane or cyclohexane, or a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane or tetracyclododecane. Group.
The hydroxyalkyl group as the substituent is preferably one having 1 to 6 carbon atoms. Specifically, at least one of the hydrogen atoms of the alkyl group mentioned as the alkyl group as the substituent is substituted with a hydroxyl group. Group.
More specifically, examples of the —SO ₂ -containing cyclic group include groups represented by the following general formulas (3-1) to (3-4).

［式中、Ａ’は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり、ｚは０〜２の整数であり、Ｒ^２７はアルキル基、アルコキシ基、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり、Ｒ”は水素原子またはアルキル基である。］

[In the formula, A ′ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, z is an integer of 0 to 2, and R ²⁷ is an alkyl group. , An alkoxy group, a halogenated alkyl group, a hydroxyl group, —COOR ″, —OC (═O) R ″, a hydroxyalkyl group or a cyano group, and R ″ is a hydrogen atom or an alkyl group.]

In the general formulas (3-1) to (3-4), A ′ represents an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom (—O—) or a sulfur atom (—S—), An oxygen atom or a sulfur atom.
The alkylene group having 1 to 5 carbon atoms in A ′ is preferably a linear or branched alkylene group, and examples thereof include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group.
When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include a group in which —O— or —S— is interposed between the terminal or carbon atoms of the alkylene group, such as —O—CH _{2. -, - CH 2 -O-CH} 2 -, - S-CH 2 -, - CH 2 -S-CH 2 - , and the like.
A ′ is preferably an alkylene group having 1 to 5 carbon atoms or —O—, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.
z may be any of 0 to 2, and is most preferably 0.
When z is 2, the plurality of R ²⁷ may be the same or different.
As the alkyl group, alkoxy group, halogenated alkyl group, —COOR ″, —OC (═O) R ″, and hydroxyalkyl group in R ²⁷ , the —SO ₂ — containing cyclic group has the above-mentioned, respectively. And the same alkyl groups, alkoxy groups, halogenated alkyl groups, —COOR ″, —OC (═O) R ″, and hydroxyalkyl groups as those which may be substituted.
Below, the specific cyclic group represented by the said general formula (3-1)-(3-4) is illustrated. In the formula, “Ac” represents an acetyl group.

Among the above, the —SO ₂ -containing cyclic group is preferably a group represented by the general formula (3-1), and the chemical formulas (3-1-1), (3-1-18), ( It is more preferable to use at least one selected from the group consisting of groups represented by any of 3-3-1) and (3-4-1), and represented by the chemical formula (3-1-1). Are most preferred.

The “lactone-containing cyclic group” refers to a cyclic group containing a ring (lactone ring) containing —O—C (═O) — in the ring skeleton. The lactone ring is counted as the first ring. When only the lactone ring is present, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.
The lactone cyclic group in the structural unit (a2) is not particularly limited, and any one can be used. Specifically, the lactone-containing monocyclic group is a group obtained by removing one hydrogen atom from a 4- to 6-membered ring lactone, such as a group obtained by removing one hydrogen atom from β-propionolactone, or γ-butyrolactone. Examples thereof include a group in which one hydrogen atom has been removed and a group in which one hydrogen atom has been removed from δ-valerolactone. Examples of the lactone-containing polycyclic group include groups in which one hydrogen atom has been removed from a bicycloalkane, tricycloalkane, or tetracycloalkane having a lactone ring.

The structural unit (a2) is not particularly limited as long as it has a —SO ₂ — containing cyclic group or a lactone-containing cyclic group, but the hydrogen atom bonded to the α-position carbon atom is A structural unit derived from an acrylate ester optionally substituted with a substituent, including a structural unit (a2 ^S ) containing a —SO ₂ -containing cyclic group, and a hydrogen atom bonded to the α-position carbon atom; At least one structural unit selected from the group consisting of a structural unit (a2 ^L ) that is a structural unit derived from an acrylate ester that may be substituted with a substituent and that contains a lactone-containing cyclic group is preferred.

-Structural unit (a2 ^S ):
More specifically, examples of the structural unit (a2 ^S ) include structural units represented by general formula (a2-0) shown below.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり、Ｒ^２８は−ＳＯ_２−含有環式基であり、Ｒ^２９は単結合または２価の連結基である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, R ²⁸ represents a —SO ₂ — containing cyclic group, and R ²⁹ represents a single bond. Or it is a bivalent coupling group. ]

In formula (a2-0), R is the same as defined above.
R ²⁸ is the same as the —SO ₂ — containing cyclic group mentioned above.
R ²⁹ may be a single bond or a divalent linking group. Since it is excellent in the effect of this invention, it is preferable that it is a bivalent coupling group.
Examples of the divalent linking group for R ^29, not particularly limited, for example, those similar to the divalent linking group for ^{Y 2} in the formula (a1-0-2) in the like. Among these, those containing an alkylene group or an ester bond (—C (═O) —O—) are preferable.
The alkylene group is preferably a linear or branched alkylene group. Specifically, the same as the linear alkylene group and the branched alkylene group mentioned as the aliphatic hydrocarbon group for Y ² can be used.
As the divalent linking group containing an ester bond, in particular, the general formula: —R ³⁰ —C (═O) —O— [wherein R ³⁰ is a divalent linking group. ] Is preferable. That is, the structural unit (a2 ^S ) is preferably a structural unit represented by the following general formula (a2-0-1).

［式中、ＲおよびＲ^２８はそれぞれ前記と同様であり、Ｒ^３０は２価の連結基である。］

[Wherein, R and R ²⁸ are the same as defined above, and R ³⁰ is a divalent linking group. ]

R ³⁰ is not particularly limited, and examples thereof include the same divalent linking groups as Y ² in formula (a1-0-2).
As the divalent linking group for R ^30, a linear or branched alkylene group, an aliphatic hydrocarbon group containing a ring in the structure, or a divalent linking group containing a hetero atom is preferable. Alternatively, a branched alkylene group or a divalent linking group containing an oxygen atom as a hetero atom is preferable.
As the linear alkylene group, a methylene group or an ethylene group is preferable, and a methylene group is particularly preferable.
As the branched alkylene group, an alkylmethylene group or an alkylethylene group is preferable, and —CH (CH ₃ ) —, —C (CH ₃ ) ₂ — or —C (CH ₃ ) ₂ CH ₂ — is particularly preferable.
Examples of the divalent linking group containing an oxygen atom, a divalent linking group containing an ether bond or an ester bond preferably, the ^{aforementioned, -Y 21 -O-Y 22 -} , - [Y 21 -C (= O) —O] _{m ′} —Y ²² — or —Y ²¹ —O—C (═O) —Y ²² — is more preferable. Y ²¹ , Y ²² and m ′ are the same as described above.

As the structural unit (a2 ^S ), a structural unit represented by general formula (a2-0-11) or (a2-0-12) shown below is particularly desirable, and represented by formula (a2-0-12). A structural unit is more preferable.

［式中、Ｒ、Ａ’、Ｒ^２７、ｚおよびＲ^３０はそれぞれ前記と同じである。］

[Wherein, R, A ′, R ²⁷ , z and R ³⁰ are the same as defined above. ]

In formula (a2-0-11), A ′ is preferably a methylene group, an oxygen atom (—O—) or a sulfur atom (—S—).
R ³⁰ is preferably a linear or branched alkylene group or a divalent linking group containing an oxygen atom. As the linear or branched alkylene group and the divalent linking group containing an oxygen atom in R ^30, the linear or branched alkylene group mentioned above and a divalent linking group containing an oxygen atom are mentioned. Examples are the same as the linking group.
As the structural unit represented by the formula (a2-0-12), a structural unit represented by the following general formula (a2-0-12a) or (a2-0-12b) is particularly preferable.

［式中、ＲおよびＡ’はそれぞれ前記と同じであり、ｃ〜ｅはそれぞれ独立に１〜３の整数である。］

[Wherein, R and A ′ are the same as defined above, and c to e are each independently an integer of 1 to 3.] ]

-Structural unit (a2 ^L ):
Examples of the structural unit (a2 ^L ) include those obtained by substituting R ²⁸ in the general formula (a2-0) with a lactone-containing cyclic group, and more specifically, the following general formula (a2- The structural unit represented by 1)-(a2-5) is mentioned.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり；Ｒ’はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり、Ｒ”は水素原子またはアルキル基であり；Ｒ^２９は単結合または２価の連結基であり、ｓ”は０〜２の整数であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり；ｍは０または１である。］

[Wherein, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; R ′ is independently a hydrogen atom, an alkyl group, an alkoxy group, or a halogenated alkyl group; , Hydroxyl group, —COOR ″, —OC (═O) R ″, a hydroxyalkyl group or a cyano group, R ″ is a hydrogen atom or an alkyl group; R ²⁹ is a single bond or a divalent linking group; s ″ is an integer of 0 to 2; A ″ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom; m is 0 or 1. ]

R in the general formulas (a2-1) to (a2-5) is the same as described above.
As the alkyl group, alkoxy group, halogenated alkyl group, —COOR ″, —OC (═O) R ″, and hydroxyalkyl group in R ′, the —SO ₂ — containing cyclic group has the above-mentioned, respectively. And the same alkyl groups, alkoxy groups, halogenated alkyl groups, —COOR ″, —OC (═O) R ″, and hydroxyalkyl groups as those which may be substituted. The same applies to R ″.
R ′ is preferably a hydrogen atom in view of industrial availability.
Examples of A ″ include the same as A ′ in the general formula (3-1). A ″ represents an alkylene group having 1 to 5 carbon atoms, an oxygen atom (—O—) or a sulfur atom (— S-) is preferable, and an alkylene group having 1 to 5 carbon atoms or -O- is more preferable. The alkylene group having 1 to 5 carbon atoms is more preferably a methylene group or dimethylmethylene group, and most preferably a methylene group.
R ²⁹ is the same as ^{R 29} in the aforementioned general formula (a2-0).
In formula (a2-1), s ″ is preferably 1 to 2.
Specific examples of the structural units represented by the general formulas (a2-1) to (a2-5) are shown below. In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

As the structural unit (a2 ^L ), at least one selected from the group consisting of structural units represented by the general formulas (a2-1) to (a2-5) is preferable, and the general formula (a2-1) to More preferably, at least one selected from the group consisting of structural units represented by (a2-3) is selected from the group consisting of structural units represented by the general formula (a2-1) or (a2-3) Particularly preferred is at least one of the above.
Among them, the formulas (a2-1-1), (a2-1-2), (a2-2-1), (a2-2-7), (a2-2-12), (a2-2-2-) 14), (a2-3-1), at least one selected from the group consisting of structural units represented by (a2-3-5) is preferred.

Moreover, as the structural unit (a2 ^L ), structural units represented by the following formulas (a2-6) to (a2-7) are also preferable.

［式中、Ｒ、Ｒ^２９は前記同様である。］

[Wherein, R and R ²⁹ are the same as defined above. ]

The structural unit (a2) contained in the component (A1) may be one type or two or more types. For example, as the structural unit (a2), only the structural unit (a2 ^S ) may be used, or only the structural unit (a2 ^L ) may be used, or they may be used in combination. As the structural unit (a2 ^S ) or the structural unit (a2 ^L ), one type may be used alone, or two or more types may be used in combination.
When the component (A1) has the structural unit (a2), the proportion of the structural unit (a2) is preferably 1 to 80 mol% with respect to the total of all the structural units constituting the component (A1). It is more preferably 10 to 70 mol%, further preferably 10 to 65 mol%, particularly preferably 10 to 60 mol%. By setting it to the lower limit value or more, the effect of containing the structural unit (a2) can be sufficiently obtained, and by setting it to the upper limit value or less, balance with other structural units can be achieved. The lithography characteristics and pattern shape of the film are improved.

(Structural unit (a3))
The component (A1) further has a structural unit (a3) containing a polar group in addition to the structural units (a0) and (a1) or in addition to the structural units (a0), (a1) and (a2). May be. When the component (A1) has the structural unit (a3), the polarity of the component (A1) after exposure is further improved. The improvement in polarity contributes to an improvement in resolution and the like, particularly in the case of an alkali development process.
Examples of the polar group include —OH, —COOH, —CN, —SO ₂ NH ₂ , —CONH ₂ , and the like. Those containing —COOH also include structural units of (α-substituted) acrylic acid.
The structural unit (a3) is preferably a structural unit containing a hydrocarbon group in which a part of hydrogen atoms is substituted with a polar group. The hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. Of these, the hydrocarbon group is more preferably an aliphatic hydrocarbon group.
Examples of the aliphatic hydrocarbon group in the hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and an aliphatic cyclic group (monocyclic group, polycyclic group). Cyclic group).
As the aliphatic cyclic group (monocyclic group, polycyclic group), for example, a resin for a resist composition for ArF excimer laser can be appropriately selected from those proposed. The aliphatic cyclic group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12. Specifically, for example, a group in which two or more hydrogen atoms have been removed from a monocycloalkane; a group in which two or more hydrogen atoms have been removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. Can be mentioned. More specifically, a group in which two or more hydrogen atoms are removed from a monocycloalkane such as cyclopentane or cyclohexane; two or more groups from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples include a group excluding a hydrogen atom. The aliphatic cyclic group may or may not have a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, a fluorine atom, and a fluorinated alkyl group having 1 to 5 carbon atoms.

The aromatic hydrocarbon group in the hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. It is preferable that carbon number of an aromatic ring is 5-30, 5-20 are more preferable, 6-15 are more preferable, and 6-12 are especially preferable. However, the carbon number does not include the carbon number in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; aromatic heterocycles in which a part of carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; etc. Is mentioned. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, as an aromatic hydrocarbon group as a divalent hydrocarbon group,
A group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocyclic ring (arylene group or heteroarylene group); A group in which one of the aromatic ring hydrogen atoms is substituted with an alkylene group (for example, benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2 A group obtained by further removing one hydrogen atom from an aromatic ring in an arylalkyl group or heteroarylalkyl group such as a naphthylethyl group); The number of carbon atoms of the alkylene group that replaces the hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocyclic ring is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1. .
The aromatic hydrocarbon group may have a substituent. For example, the hydrogen atom bonded to the aromatic ring of the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxygen atom (═O).
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
Examples of the halogen atom as a substituent for the aromatic hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which some or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.

  As the structural unit (a3), structural units represented by general formula (a3-1) shown below are preferred.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基である。Ｌ^０は−Ｃ（＝Ｏ）−Ｏ−、−Ｃ（＝Ｏ）−ＮＲ^ｎ−（Ｒ^ｎは水素原子又は炭素数１〜５のアルキル基である）又は単結合である。Ｒ^０は−ＣＯＯＨ、または置換基として−ＯＨ、−ＣＯＯＨ、−ＣＮ、−ＳＯ_２ＮＨ_２、−Ｃ（Ｒ^ｒ１）（Ｒ^ｒ２）（ＯＨ）及び−ＣＯＮＨ_２からなる群より選択される少なくとも一種の基を有する炭化水素基であり、任意の位置に酸素原子又は硫黄原子を有していてもよい。Ｒ^ｒ１、Ｒ^ｒ２はそれぞれ独立に、水素原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. L ⁰ is —C (═O) —O—, —C (═O) —NR ⁿ — (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms) or a single bond. R ⁰ is at least selected from the group consisting of —COOH, or —OH, —COOH, —CN, —SO ₂ NH ₂ , —C (R ^r1 ) (R ^r2 ) (OH) and —CONH ₂ as a substituent. It is a hydrocarbon group having a kind of group, and may have an oxygen atom or a sulfur atom at an arbitrary position. R ^r1 and R ^r2 are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. ]

In the formula (a3-1), R is the same as described above.
In the formula (a3-1), L ⁰ is —C (═O) —O—, —C (═O) —NR ⁿ — (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. ) Or a single bond. The alkyl group for R ⁿ is the same as the alkyl group for R.

In the formula (a3-1), R ⁰ includes —OH, —COOH, —CN, —SO ₂ NH ₂ , —C (R ^r1 ) (R ^r2 ) (OH), and —CONH ₂ as substituents. It is a hydrocarbon group having at least one group selected from the group, and may have an oxygen atom or a sulfur atom at an arbitrary position.
The “hydrocarbon group having a substituent” means that at least a part of hydrogen atoms bonded to the hydrocarbon group is substituted with a substituent.
The hydrocarbon group for R ⁰ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
As the aliphatic hydrocarbon group for R ^{0, a} linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) or an aliphatic cyclic group (monocyclic group, polycyclic group) Group), and the description thereof is the same as described above.
The aromatic hydrocarbon group in R ⁰ is a hydrocarbon group having an aromatic ring, and this description is the same as described above.
In —C (R ^r1 ) (R ^r2 ) (OH) as a substituent for R ⁰ , R ^r1 and R ^r2 each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or 1 to 5 carbon atoms. Of the halogenated alkyl group. Examples of the alkyl group having 1 to 5 carbon atoms and the halogenated alkyl group having 1 to 5 carbon atoms include the alkyl group having 1 to 5 carbon atoms and the halogenated alkyl group having 1 to 5 carbon atoms as the substituent at the α-position described above. It is the same.

However, R ⁰ may have an oxygen atom or a sulfur atom at an arbitrary position. The phrase “may have an oxygen atom or a sulfur atom at any position” means a carbon atom constituting a hydrocarbon group or a hydrocarbon group having a substituent (including the carbon atom of the substituent portion). ) May be substituted with an oxygen atom or a sulfur atom, or a hydrogen atom bonded to a hydrocarbon group may be substituted with an oxygen atom or a sulfur atom.
Hereinafter, R ⁰ having an oxygen atom (O) at an arbitrary position will be exemplified as an example.

［式中、Ｗ^００は炭化水素基であり、Ｒ^ｍは炭素数１〜５のアルキレン基である。］

[Wherein, W ⁰⁰ is a hydrocarbon group, and R ^m is an alkylene group having 1 to 5 carbon atoms. ]

In the above formula, W ⁰⁰ is a hydrocarbon group, and examples thereof include the same as R ⁰ in the formula (a3-1). W ⁰⁰ is preferably an aliphatic hydrocarbon group, more preferably an aliphatic cyclic group (monocyclic group or polycyclic group).
R ^m is preferably linear or branched, preferably an alkylene group having 1 to 3 carbon atoms, and more preferably a methylene group or an ethylene group.

More preferable examples of the structural unit (a3) include structural units derived from (α-substituted) acrylic acid, and any one of the following general formulas (a3-11) to (a3-13): Examples of the structural unit are as follows.
Examples of the structural unit derived from (α-substituted) acrylic acid include structural units in which L ⁰ in the formula (a3-1) is a single bond and R ⁰ is —COOH.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基である。Ｗ^０１は置換基として−ＯＨ、−ＣＯＯＨ、−ＣＮ、−ＳＯ_２ＮＨ_２、−Ｃ（Ｒ^ｒ１）（Ｒ^ｒ２）（ＯＨ）及び−ＣＯＮＨ_２からなる群より選択される少なくとも一種の基を有する芳香族炭化水素基である。Ｐ^０２及びＰ^０３はそれぞれ−Ｃ（＝Ｏ）−Ｏ−又は−Ｃ（＝Ｏ）−ＮＲ^ｎ−（Ｒ^ｎは水素原子又は炭素数１〜５のアルキル基である）である。Ｗ^０２は置換基として−ＯＨ、−ＣＯＯＨ、−ＣＮ、−ＳＯ_２ＮＨ_２、−Ｃ（Ｒ^ｒ１）（Ｒ^ｒ２）（ＯＨ）及び−ＣＯＮＨ_２からなる群より選択される少なくとも一種の基を有する環状の炭化水素基であり、任意の位置に酸素原子又は硫黄原子を有していてもよい。Ｗ^０３は置換基として−ＯＨ、−ＣＯＯＨ、−ＣＮ、−ＳＯ_２ＮＨ_２、−Ｃ（Ｒ^ｒ１）（Ｒ^ｒ２）（ＯＨ）及び−ＣＯＮＨ_２からなる群より選択される少なくとも一種の基を有する直鎖状の炭化水素基である。Ｒ^ｒ１、Ｒ^ｒ２は前記同様である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. W ⁰¹ represents at least one group selected from the group consisting of —OH, —COOH, —CN, —SO ₂ NH ₂ , —C (R ^r1 ) (R ^r2 ) (OH) and —CONH ₂ as a substituent. It is an aromatic hydrocarbon group. P ⁰² and P ⁰³ are each —C (═O) —O— or —C (═O) —NR ⁿ — (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms). W ⁰² represents at least one group selected from the group consisting of —OH, —COOH, —CN, —SO ₂ NH ₂ , —C (R ^r1 ) (R ^r2 ) (OH) and —CONH ₂ as a substituent. A cyclic hydrocarbon group having an oxygen atom or a sulfur atom at an arbitrary position. W ⁰³ represents at least one group selected from the group consisting of —OH, —COOH, —CN, —SO ₂ NH ₂ , —C (R ^r1 ) (R ^r2 ) (OH) and —CONH ₂ as a substituent. It has a linear hydrocarbon group. R ^r1 and R ^r2 are the same as described above. ]

{Structural unit represented by general formula (a3-11)}
In the formula (a3-11), R is the same as described for R in the formula (a3-1).
The aromatic hydrocarbon group for W ⁰¹ is the same as that described for the aromatic hydrocarbon group for R ⁰ in formula (a3-1).
Specific examples of preferable structural units represented by general formula (a3-11) are shown below. In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

{Structural unit represented by general formula (a3-12)}
In the formula (a3-12), R is the same as described for R in the formula (a3-1).
P ⁰² is —C (═O) —O— or —C (═O) —NR ⁿ — (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), and —C (═O ) -O-. The alkyl group for R ⁿ is the same as the alkyl group for R.
The cyclic hydrocarbon group in W ⁰² is an aliphatic cyclic group (monocyclic group or polycyclic group) or aromatic hydrocarbon exemplified in the description of R ⁰ in the formula (a3-1). Examples of each group are the same.
W ⁰² may have an oxygen atom or a sulfur atom at an arbitrary position, and this description is the same as the description of R ⁰ in the formula (a3-1).
Specific examples of preferred structural units represented by general formula (a3-12) are shown below. In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

{Structural unit represented by general formula (a3-13)}
In the formula (a3-13), R is the same as described for R in the formula (a3-1).
P ⁰³ is —C (═O) —O— or —C (═O) —NR ⁿ — (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), and —C (═O ) -O-. The alkyl group for R ⁿ is the same as the alkyl group for R.
The linear hydrocarbon group for W ⁰³ preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and still more preferably 1 to 3 carbon atoms.
The linear hydrocarbon group for W ⁰³ may further have a substituent (a) other than —OH, —COOH, —CN, —SO ₂ NH _2, and —CONH ₂ . Examples of the substituent (a) include an alkyl group having 1 to 5 carbon atoms, an aliphatic cyclic group (monocyclic group, polycyclic group), a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, and the like. Can be mentioned. The number of carbon atoms of the aliphatic cyclic group (monocyclic group or polycyclic group) in the substituent (a) is preferably 3 to 30, more preferably 5 to 30, and further preferably 5 to 20 Preferably, 6-15 is especially preferable, and 6-12 is the most preferable. Specifically, for example, a group in which two or more hydrogen atoms are removed from a monocycloalkane; a group in which one or more hydrogen atoms are removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. Can be mentioned. More specifically, a group in which two or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane or cyclohexane; one or more polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane Examples include a group excluding a hydrogen atom.
Further, straight-chain hydrocarbon group for W ^03, as in the structural unit represented by the following general formula as an example (a3-13-a), may have a plurality of substituents (a), A plurality of substituents (a) may be bonded to each other to form a ring.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基である。Ｒ^ａ１及びＲ^ａ２はそれぞれ独立に炭素数１〜５のアルキル基、脂肪族環式基（単環式基、多環式基）、フッ素原子、又は炭素数１〜５のフッ素化アルキル基である。但し、Ｒ^ａ１とＲ^ａ２とが相互に結合して環を形成してもよい。ｑ^０は１〜４の整数である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. R ^a1 and R ^a2 are each independently an alkyl group having 1 to 5 carbon atoms, an aliphatic cyclic group (monocyclic group or polycyclic group), a fluorine atom, or a fluorinated alkyl group having 1 to 5 carbon atoms. is there. However, R ^a1 and R ^a2 may be bonded to each other to form a ring. q ⁰ is an integer of 1 to 4. ]

In the formula (a3-13-a), R is the same as described for R in the formula (a3-1).
The aliphatic cyclic group (monocyclic group or polycyclic group) in R ^a1 and R ^a2 is the same as the aliphatic cyclic group (monocyclic group or polycyclic group) in the substituent (a). is there.
R ^a1 and R ^a2 may be bonded to each other to form a ring. In this ^case, a ^{R a1,} and ^{R a2,} cyclic group is formed by the carbon atoms to which the ^{R a1} and ^{R a2} are bonded together. The cyclic group may be a monocyclic group or a polycyclic group. Specifically, an aliphatic cyclic group (monocyclic group, Examples thereof include groups in which one or more hydrogen atoms have been removed from the monocycloalkane or polycycloalkane exemplified in the description of the polycyclic group).
q ⁰ is preferably 1 or 2, and more preferably 1.

Specific examples of preferable structural units represented by general formula (a3-13) are shown below. In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

The structural unit (a3) contained in the component (A1) may be one type or two or more types.
When the component (A1) has the structural unit (a3), the proportion of the structural unit (a3) is preferably 0 to 85 mol% with respect to all the structural units constituting the component (A1). 80 mol% is more preferable. By setting the proportion of the structural unit (a3) to be equal to or higher than the lower limit value, the effects (resolution, lithography characteristics, pattern shape improvement effect) due to the inclusion of the structural unit (a3) can be sufficiently obtained. This makes it easier to balance with other structural units.

(Other structural units)
The component (A1) may contain other structural units (hereinafter referred to as structural unit (a4)) other than the structural units (a0) to (a3) as long as the effects of the present invention are not impaired.
The structural unit (a4) is not particularly limited as long as it is another structural unit not classified into the structural units (a0) to (a3) described above. A number of hitherto known materials can be used for resist resins such as lasers.
As the structural unit (a4), for example, a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, which is an acid non-dissociable aliphatic group A structural unit containing a polycyclic group, a structural unit derived from a styrene monomer, a structural unit derived from a vinyl naphthalene monomer, or the like is preferable. Examples of the polycyclic group include those exemplified in the case of the structural unit (a1), and for ArF excimer laser and KrF excimer laser (preferably for ArF excimer laser). A number of hitherto known materials can be used as the resin component of the resist composition.
In particular, at least one selected from a tricyclodecanyl group, an adamantyl group, a tetracyclododecanyl group, an isobornyl group, and a norbornyl group is preferable in terms of industrial availability. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.
Specific examples of the structural unit (a4) include those represented by the following general formulas (a4-1) to (a4-5).

［式中、Ｒは前記と同じである。］

[Wherein, R is the same as defined above. ]

As the structural unit (a4), one type may be used alone, or two or more types may be used in combination.
When the component (A1) contains the structural unit (a4), the proportion of the structural unit (a4) is preferably 1 to 20 mol% with respect to the total of all the structural units constituting the component (A1). 15 mol% is more preferable and 1-10 mol% is further more preferable.

The component (A1) is a polymer having the structural unit (a0), and is preferably a copolymer having the structural unit (a1) in addition to the structural unit (a0).
Examples of such a copolymer include a copolymer consisting of structural units (a0), (a1) and (a3); a copolymer consisting of structural units (a0), (a1) and (a2); a0), (a1), a copolymer comprising (a2) and (a3); a copolymer comprising the structural units (a0), (a1), (a2), (a3) and (a4), etc. .

The mass average molecular weight (Mw) of the component (A1) (polystyrene conversion standard by gel permeation chromatography) is not particularly limited, preferably 1000 to 50000, more preferably 1500 to 30000, most preferably 2500 to 20000. preferable. If it is below the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and if it is above the lower limit of this range, dry etching resistance and resist pattern cross-sectional shape are good.
Further, the dispersity (Mw / Mn) of the component (A1) is not particularly limited, and is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and 1.2 to 2 .5 is most preferred.
In addition, Mn shows a number average molecular weight.

In the component (A), as the component (A1), one type may be used alone, or two or more types may be used in combination.
The proportion of the component (A1) in the component (A) is preferably 25% by mass or more, more preferably 50% by mass, further preferably 75% by mass, and 100% by mass with respect to the total mass of the component (A). May be. When the ratio is 25% by mass or more, effects such as lithography characteristics are improved.

The component (A) may contain a base component other than the component (A1) (hereinafter, this base component is referred to as “component (A2)”) as long as the effects of the present invention are not impaired.
As the component (A2), a low molecular compound having a molecular weight of 500 or more and less than 4000 and having an acid dissociable group and a hydrophilic group as exemplified in the description of the component (A1) may be used. . Specific examples include those in which some or all of the hydrogen atoms of the hydroxyl group of the compound having a plurality of phenol skeletons are substituted with the acid dissociable group.
Examples of the low molecular weight compound include a sensitizer in a non-chemically amplified g-line or i-line resist, and a part of the hydrogen atom of the hydroxyl group of a low molecular weight phenol compound known as a heat resistance improver. Those substituted with a dissociable group are preferred, and any of them can be used arbitrarily.
Examples of the low molecular weight phenol compound include bis (4-hydroxyphenyl) methane, bis (2,3,4-trihydroxyphenyl) methane, 2- (4-hydroxyphenyl) -2- (4′-hydroxyphenyl). ) Propane, 2- (2,3,4-trihydroxyphenyl) -2- (2 ′, 3 ′, 4′-trihydroxyphenyl) propane, tris (4-hydroxyphenyl) methane, bis (4-hydroxy-) 3,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -3, 4-dihydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -3,4-dihydroxypheny Rumethane, bis (4-hydroxy-3-methylphenyl) -3,4-dihydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methylphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl- 4-hydroxy-6-methylphenyl) -3,4-dihydroxyphenylmethane, 1- [1- (4-hydroxyphenyl) isopropyl] -4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene, Examples include 2 to 6 nuclei of formalin condensates of phenols such as phenol, m-cresol, p-cresol and xylenol. Of course, it is not limited to these. In particular, a phenol compound having 2 to 6 triphenylmethane skeletons is preferable because of excellent resolution and line edge roughness (LWR). The acid dissociable group is not particularly limited, and examples thereof include those described above.

  In the resist composition of the present invention, the content of the component (A) may be adjusted according to the resist film thickness to be formed.

<Optional component>
[Component (B)]
In addition to the component (A), the resist composition of the present invention may further contain an acid generator component (B) that generates an acid upon exposure (hereinafter referred to as “component (B)”). .
The component (B) is not particularly limited, and those that have been proposed as acid generators for chemically amplified resists can be used.
Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, poly (bissulfonyl) diazomethanes, and the like. There are various known diazomethane acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators, and the like.

  As the onium salt acid generator, for example, a compound represented by the following general formula (b-1) or (b-2) can be used.

［式中、Ｒ^１”〜Ｒ^３”，Ｒ^５”〜Ｒ^６”はそれぞれ独立に置換基を有していてもよいアリール基、アルキル基又はアルケニル基を表す。式（ｂ−１）におけるＲ^１”〜Ｒ^３”のうち、いずれか二つが相互に結合して式中のイオウ原子と共に環を形成してもよい。Ｒ^４”は、置換基を有していてもよいアルキル基、ハロゲン化アルキル基、アリール基、またはアルケニル基を表す。］

[Wherein, R ¹ ″ to R ³ ″ and R ⁵ ″ to R ⁶ ″ each independently represents an aryl group, an alkyl group or an alkenyl group which may have a substituent. Any two of R ¹ ″ to R ³ ″ in formula (b-1) may be bonded to each other to form a ring together with the sulfur atom in the formula. R ⁴ ″ represents an alkyl group, a halogenated alkyl group, an aryl group, or an alkenyl group which may have a substituent.

Wherein ^{(b-1), R 1} "~R 3" is the same as ^R 1 ^{"~R 3"} in the general formula (c-1). Among them, since the further improved lithography properties and resist pattern ^shape, of R 1 "to R ^3", it is preferable that at least one is an aryl ^group, among the R 1 "~R ^3", 2 one The above is more preferably an aryl group, and it is particularly preferable that all of R ¹ ″ to R ³ ″ are aryl groups.
In formula (b-2), R ⁵ ″ to R ⁶ ″ are the same as R ⁵ ″ to R ⁶ ″ in general formula (c-2). Among them, since the lithography properties and resist pattern shape is further ^improved, among R 5 "~R ^6", it is preferable that at least one is an aryl ^group, any aryl group R 5 "~R ^6" It is more preferable that

In the formulas (b-1) to (b-2), R ⁴ ″ represents an alkyl group, a halogenated alkyl group, an aryl group, or an alkenyl group which may have a substituent.
The alkyl group for R ⁴ ″ may be linear, branched or cyclic.
The linear or branched alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.
The cyclic alkyl group preferably has 4 to 15 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms.
Examples of the halogenated alkyl group for R ⁴ ″ include groups in which part or all of the hydrogen atoms of the linear, branched, or cyclic alkyl group have been substituted with halogen atoms. A fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.
In the halogenated alkyl group, the ratio of the number of halogen atoms to the total number of halogen atoms and hydrogen atoms contained in the halogenated alkyl group (halogenation rate (%)) is preferably 10 to 100%. 50 to 100% is preferable, and 100% is most preferable. The higher the halogenation rate, the better the acid strength.
The aryl group for R ⁴ ″ is preferably an aryl group having 6 to 20 carbon atoms.
The alkenyl group in R ⁴ ″ is preferably an alkenyl group having 2 to 10 carbon atoms.
In the above R ⁴ ″, “may have a substituent” means that a part or all of the hydrogen atoms in the alkyl group, halogenated alkyl group, aryl group, or alkenyl group are a substituent (hydrogen atom). It may be substituted with other atoms or groups).
The number of substituents in R ⁴ ″ may be one, or two or more.

Examples of the substituent include a halogen atom, a hetero atom, an alkyl group, a formula: R ^X -Q ^1- [where Q ¹ is a divalent linking group containing an oxygen atom, and R ^X represents a substituent. It is a C3-C30 hydrocarbon group which may have. ] Etc. which are represented by these.
Examples of the halogen atom and alkyl group include the same groups as those described as the halogen atom and alkyl group in the halogenated alkyl group in R ⁴ ″.
Examples of the hetero atom include an oxygen atom, a nitrogen atom, and a sulfur atom.

In the group represented by R ^X —Q ¹ —, Q ¹ is a divalent linking group containing an oxygen atom.
Q ¹ may contain an atom other than an oxygen atom. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, oxygen atoms, sulfur atoms, and nitrogen atoms.
Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond; —O—), an ester bond (—C (═O) —O—), and an amide bond (—C (═O) —NH. -), A carbonyl group (-C (= O)-), a non-hydrocarbon oxygen atom-containing linking group such as a carbonate bond (-O-C (= O) -O-); the non-hydrocarbon oxygen atom Examples include a combination of a containing linking group and an alkylene group.
Examples of the combination include —R ⁹¹ —O—, —R ⁹² —O—C (═O) —, —C (═O) —O—R ⁹² —, —C (═O) —O—R. ⁹³ —O—C (═O) — (wherein R ^{91 to} R ⁹³ are each independently an alkylene group).
The alkylene group for R ^{91 to} R ⁹³ is preferably a linear or branched alkylene group, and the alkylene group preferably has 1 to 12 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably 1 to 3 carbon atoms. preferable.
Q ¹ is preferably a divalent linking group containing an ester bond or an ether bond, and in particular, —R ⁹¹ —O—, —R ⁹² —O—C (═O) — or —C (═O) — O—R ⁹³ —O—C (═O) — is preferred.

In the group represented by R ^X -Q ^1- , the hydrocarbon group of R ^X may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group.

The aromatic hydrocarbon group is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, more preferably 5 to 20, still more preferably 6 to 15, and most preferably 6 to 12. However, the carbon number does not include the carbon number in the substituent.
Specific examples of the aromatic hydrocarbon group include a hydrogen atom from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, and a phenanthryl group. Aryl groups such as aryl group, benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc., from which one is removed. The number of carbon atoms in the alkyl chain in the arylalkyl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

The aromatic hydrocarbon group may have a substituent. For example, a part of carbon atoms constituting the aromatic ring of the aromatic hydrocarbon group may be substituted with a hetero atom, and the hydrogen atom bonded to the aromatic ring of the aromatic hydrocarbon group is substituted with the substituent. May be.
Examples of the former include heteroaryl groups in which some of the carbon atoms constituting the ring of the aryl group are substituted with heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and aromatic hydrocarbons in the arylalkyl groups. Examples include heteroarylalkyl groups in which some of the carbon atoms constituting the ring are substituted with the above heteroatoms.
Examples of the substituent of the aromatic hydrocarbon group in the latter example include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxygen atom (═O).
The alkyl group as a substituent of the aromatic hydrocarbon group is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. preferable.
The alkoxy group as a substituent of the aromatic hydrocarbon group is preferably an alkoxy group having 1 to 5 carbon atoms, and is a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert- A butoxy group is preferable, and a methoxy group and an ethoxy group are most preferable.
Examples of the halogen atom as a substituent for the aromatic hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent of the aromatic hydrocarbon group include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.

The aliphatic hydrocarbon group for R ^X may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The aliphatic hydrocarbon group may be linear, branched or cyclic.
In R ^X , the aliphatic hydrocarbon group may be a group in which a part of carbon atoms constituting the aliphatic hydrocarbon group may be substituted with a substituent containing a hetero atom, and the hydrogen constituting the aliphatic hydrocarbon group Some or all of the atoms may be substituted with a substituent containing a hetero atom.
The “heteroatom” in R ^X is not particularly limited as long as it is an atom other than a carbon atom and a hydrogen atom, and examples thereof include a halogen atom, an oxygen atom, a sulfur atom, and a nitrogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, an iodine atom, and a bromine atom.
The substituent containing a hetero atom may be composed of only the hetero atom, or may be a group containing a group or atom other than the hetero atom.
Specific examples of the substituent for substituting a part of the carbon atom include —O—, —C (═O) —O—, —C (═O) —, —O—C (═O) —O. —, —C (═O) —NH—, —NH— (H may be substituted with a substituent such as an alkyl group, an acyl group, etc.), —S—, —S (═O) ₂ —, — S (= O) ₂ —O— and the like can be mentioned. When the aliphatic hydrocarbon group is cyclic, these substituents may be included in the ring structure.
Specific examples of the substituent for substituting part or all of the hydrogen atoms include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (═O), and a cyano group.
The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and a methoxy group or an ethoxy group. Is most preferred.
As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.
As the halogenated alkyl group, a part or all of hydrogen atoms of an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a tert-butyl group, etc. And a group substituted with a halogen atom.

Examples of the aliphatic hydrocarbon group include a linear or branched saturated hydrocarbon group, a linear or branched monovalent unsaturated hydrocarbon group, or a cyclic aliphatic hydrocarbon group (aliphatic ring). Formula group) is preferred.
The linear saturated hydrocarbon group (alkyl group) preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group Group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, heicosyl group, docosyl group and the like.
The branched saturated hydrocarbon group (alkyl group) preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, Examples include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.

As an unsaturated hydrocarbon group, it is preferable that carbon number is 2-10, 2-5 are preferable, 2-4 are preferable, and 3 is especially preferable. Examples of the linear monovalent unsaturated hydrocarbon group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched monovalent unsaturated hydrocarbon group include a 1-methylpropenyl group and a 2-methylpropenyl group.
Among the above, the unsaturated hydrocarbon group is particularly preferably a propenyl group.

The aliphatic cyclic group may be a monocyclic group or a polycyclic group. The number of carbon atoms is preferably 3 to 30, more preferably 5 to 30, further preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12.
When the aliphatic cyclic group does not contain a substituent containing a hetero atom in the ring structure, the aliphatic cyclic group is preferably a polycyclic group, and has one or more hydrogen atoms from the polycycloalkane. Excluded groups are preferred, and most preferred are groups in which one or more hydrogen atoms have been removed from adamantane.
When the aliphatic cyclic group includes a substituent containing a hetero atom in the ring structure, examples of the substituent containing a hetero atom include —O—, —C (═O) —O—, —S—. , —S (═O) ₂ — and —S (═O) ₂ —O— are preferable. Specific examples of the aliphatic cyclic group include groups represented by the following formulas (L1) to (L6) and (S1) to (S4).

［式中、Ｑ”は炭素数１〜５のアルキレン基、−Ｏ−、−Ｓ−、−Ｏ−Ｒ^９４−または−Ｓ−Ｒ^９５−であり、Ｒ^９４およびＲ^９５はそれぞれ独立に炭素数１〜５のアルキレン基であり、ｍは０または１の整数である。］

[Wherein, Q ″ is an alkylene group having 1 to 5 carbon atoms, —O—, —S—, —O—R ⁹⁴ — or —S—R ⁹⁵ —, wherein R ⁹⁴ and R ⁹⁵ are each independently carbon. An alkylene group of 1 to 5 and m is an integer of 0 or 1.]

In the formula, examples of the alkylene group for Q ″, R ⁹⁴ and R ⁹⁵ include the same alkylene groups as those described above for R ^{91 to} R ⁹³ .
In these aliphatic cyclic groups, a part of hydrogen atoms bonded to carbon atoms constituting the ring structure may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxygen atom (═O).
As said alkyl group, a C1-C5 alkyl group is preferable, and it is especially preferable that they are a methyl group, an ethyl group, a propyl group, n-butyl group, and a tert- butyl group.
Examples of the alkoxy group and the halogen atom are the same as those exemplified as the substituent for substituting part or all of the hydrogen atoms of the aliphatic hydrocarbon group when R ^x is an aliphatic hydrocarbon group. It is done.

Among the above, R ^X is preferably a cyclic group which may have a substituent. The cyclic group may be an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a substituent. It is preferably an aliphatic cyclic group that may be used.
The aromatic hydrocarbon group is preferably a naphthyl group which may have a substituent or a phenyl group which may have a substituent.
As the aliphatic cyclic group which may have a substituent, a polycyclic aliphatic cyclic group which may have a substituent is preferable. Examples of the polycyclic aliphatic cyclic group include groups obtained by removing one or more hydrogen atoms from the polycycloalkane, and groups represented by the above (L2) to (L6) and (S3) to (S4). Etc. are preferred.

Also, R ^X, since the lithography properties, resist pattern shape is further improved, which has a polar moiety is particularly preferred.
As having a polar moiety, for example, substituted groups in which some of the carbon atoms constituting the aliphatic cyclic group of the above-mentioned R ^X includes a heteroatom, i.e., -O -, - C (= O) -O -, -C (= O)-, -O-C (= O) -O-, -C (= O) -NH-, -NH- (H is substituted with a substituent such as an alkyl group or an acyl group. may _{be), - S -, - S} (= O) 2 -, - S (= O) 2 -O- , etc., in include those substituted.

Among the above, R ⁴ ″ preferably has R ^X -Q ^1- as a substituent. In this case, R ⁴ ″ has R ^X -Q ¹ -Y ^1- [wherein Q ¹ and R ^X is the same as above, and Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms or an optionally substituted fluorinated alkylene group having 1 to 4 carbon atoms. is there. ] Is preferable.
In the group represented by R ^X —Q ¹ —Y ¹ —, the alkylene group for Y ¹ includes the same alkylene groups as those described above for Q ¹ having 1 to 4 carbon atoms.
Examples of the fluorinated alkylene group for Y ¹ include groups in which some or all of the hydrogen atoms of the alkylene group have been substituted with fluorine atoms.
As Y ^1, _{specifically, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 -, - CF (CF 2 CF 3) -, _{-C (CF 3) 2 -,} - CF 2 CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 CF 2 -, - CF 2 CF (CF 3) CF 2 -, - CF (CF 3) CF (CF ₃ ) —, —C (CF ₃ ) ₂ CF ₂ —, —CF (CF ₂ CF ₃ ) CF ₂ —, —CF (CF ₂ CF ₂ CF ₃ ) —, —C (CF ₃ ) (CF _{2 CF 3) -; - CHF} -, - CH 2 CF 2 -, - CH 2 CH 2 CF 2 -, - CH 2 CF 2 CF 2 -, - CH (CF 3) CH 2 -, - CH (CF 2 _{CF 3) -, - C (} CH 3) (CF 3) -, - CH 2 CH 2 CH 2 CF 2 -, - C H ₂ CH ₂ CF ₂ CF ₂ —, —CH (CF ₃ ) CH ₂ CH ₂ —, —CH ₂ CH (CF ₃ ) CH ₂ —, —CH (CF ₃ ) CH (CF ₃ ) —, —C ( _{CF 3) 2 CH 2 -;} - CH 2 -, - CH 2 CH 2 -, - CH 2 CH 2 CH 2 -, - CH (CH 3) CH 2 -, - CH (CH 2 CH 3) -, - _{C (CH 3) 2 -,} - CH 2 CH 2 CH 2 CH 2 -, - CH (CH 3) CH 2 CH 2 -, - CH 2 CH (CH 3) CH 2 -, - CH (CH 3) CH _{(CH 3) -, - C} (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - CH (CH 2 CH 2 CH 3) -, - C (CH 3) (CH 2 CH ₃ ) — and the like.

Y ¹ is preferably a fluorinated alkylene group, and particularly preferably a fluorinated alkylene group in which the carbon atom bonded to the adjacent sulfur atom is fluorinated. Examples of such fluorinated alkylene _{group, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 -, - CF 2 CF 2 CF 2 CF 2 _{-, - CF (CF 3)} CF 2 CF 2 -, - CF 2 CF (CF 3) CF 2 -, - CF (CF 3) CF (CF 3) -, - C (CF 3) 2 CF 2 -, _{-CF (CF 2 CF 3) CF} 2 -; - CH 2 CF 2 -, - CH 2 CH 2 CF 2 -, - CH 2 CF 2 CF 2 -; - CH 2 CH 2 CH 2 CF 2 -, - CH ₂ CH ₂ CF ₂ CF ₂ —, —CH ₂ CF ₂ CF ₂ CF ₂ — and the like can be mentioned.
Of _{these, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, or _CH 2 _CF 2 CF ₂ - is _{preferable, -CF 2 -, - CF 2} CF 2 - or -CF ₂ CF ₂ CF ₂ - is more preferable, -CF ₂ - is particularly preferred.

The alkylene group or fluorinated alkylene group may have a substituent. An alkylene group or a fluorinated alkylene group has a “substituent” means that part or all of the hydrogen atom or fluorine atom in the alkylene group or fluorinated alkylene group is substituted with an atom or group other than a hydrogen atom and a fluorine atom. Means that
Examples of the substituent that the alkylene group or fluorinated alkylene group may have include an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, and a hydroxyl group.

"The, ^{R 4} in the above formula (b-1)" ^{R 4} in the formula (b-2) include the same as.

  Specific examples of the onium salt acid generators represented by formulas (b-1) and (b-2) include diphenyliodonium trifluoromethanesulfonate or nonafluorobutanesulfonate, bis (4-tert-butylphenyl) iodonium. Trifluoromethane sulfonate or nonafluorobutane sulfonate, triphenylsulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, tri (4-methylphenyl) sulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its Nonafluorobutanesulfonate, dimethyl (4-hydroxynaphthyl) sulfonium trifluoromethanesulfonate, its heptaful Lopropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of monophenyldimethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; trifluoromethanesulfonate of diphenylmonomethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate (4-methylphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, (4-methoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate , Trifluoromethanesulfonate of tri (4-tert-butyl) phenylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of diphenyl (1- (4-methoxy) naphthyl) sulfonium, its heptafluoropropane Sulfonate or its nonafluorobutane sulfonate, di (1-naphthyl) phenyl sulphonium trifluoromethane sulphonate, its heptafluoropropane sulphonate or its nonafluorobutane sulphonate; 1-phenyltetrahydrothiophenium trifluoromethane sulphonate, its heptafluoropropane sulphonate Or nonafluorobutanesulfonate thereof; 1- (4-methylphenyl) ) Tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropane sulfonate 1- (4-methoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; 1- (4-ethoxynaphthalene-1- Yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonaflu 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; 1-phenyltetrahydrothiopyranium trifluoromethanesulfonate , Its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (4-hydroxyphenyl) tetrahydrothiopyranium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (3,5-dimethyl -4-Hydroxyphenyl) tetrahydrothiopyranium trifluoromethanesulfonate, its heptafluoropropanes Honeto or nonafluorobutanesulfonate; 1- (4-methylphenyl) trifluoromethanesulfonate tetrahydrothiophenium Pila chloride, heptafluoropropane sulfonate or its nonafluorobutane sulfonate, and the like.

  In addition, the anion portion of these onium salts may be substituted with alkyl sulfonates such as methanesulfonate, n-propanesulfonate, n-butanesulfonate, n-octanesulfonate, 1-adamantanesulfonate, 2-norbornanesulfonate; d-camphor-10-sulfonate. Further, onium salts substituted with sulfonates such as benzenesulfonate, perfluorobenzenesulfonate, and p-toluenesulfonate can also be used.

  Moreover, the onium salt which replaced the anion part of these onium salts by the anion represented by either of following formula (b1)-(b8) can also be used.

［式中、ｙは１〜３の整数であり、ｑ１〜ｑ２はそれぞれ独立に１〜５の整数であり、ｑ３は１〜１２の整数であり、ｔ３は１〜３の整数であり、ｒ１〜ｒ２はそれぞれ独立に０〜３の整数であり、ｉは１〜２０の整数であり、Ｒ^５０は置換基であり、ｍ１〜ｍ５はそれぞれ独立に０または１であり、ｖ０〜ｖ５はそれぞれ独立に０〜３の整数であり、ｗ１〜ｗ５はそれぞれ独立に０〜３の整数であり、Ｑ”は前記と同じである。］

[Wherein y is an integer of 1 to 3, q1 and q2 are each independently an integer of 1 to 5, q3 is an integer of 1 to 12, t3 is an integer of 1 to 3, and r1 ~ R2 is each independently an integer of 0 to 3, i is an integer of 1 to 20, R ⁵⁰ is a substituent, m1 to m5 are each independently 0 or 1, and v0 to v5 are each Are independently an integer of 0 to 3, w1 to w5 are each independently an integer of 0 to 3, and Q ″ is the same as above.]

As the substituent of R ^50, the same as those described as the substituent that the aliphatic hydrocarbon group may have and the substituent that the aromatic hydrocarbon group may have in the above R ^X Is mentioned.
Code (r1 and r2, w1 to w5) attached to R ⁵⁰ when it is 2 or more integer, a plurality of ^{R 50} in the compound may be the same, respectively, it may be different.

As the onium salt-based acid generator, in the general formula (b-1) or (b-2), the anion moiety ^(R 4 "SO ₃ ^-) of the following general formula (b-3) or (b- An onium salt acid generator substituted with the anion represented by 4) can also be used (the cation moiety is the same as the cation moiety in the formula (b-1) or (b-2)).

［式中、Ｘ”は、少なくとも１つの水素原子がフッ素原子で置換された炭素数２〜６のアルキレン基を表し；Ｙ”、Ｚ”は、それぞれ独立に、少なくとも１つの水素原子がフッ素原子で置換された炭素数１〜１０のアルキル基を表す。］

[Wherein X ″ represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom; Y ″ and Z ″ each independently represent at least one hydrogen atom as a fluorine atom; Represents an alkyl group having 1 to 10 carbon atoms and substituted with

X ″ is a linear or branched alkylene group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkylene group has 2 to 6 carbon atoms, preferably 3 to 5 carbon atoms, Most preferably, it has 3 carbon atoms.
Y ″ and Z ″ are each independently a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkyl group has 1 to 10 carbon atoms, preferably Has 1 to 7 carbon atoms, more preferably 1 to 3 carbon atoms.
The carbon number of the alkylene group of X ″ or the carbon number of the alkyl group of Y ″ and Z ″ is preferably as small as possible because the solubility in the resist solvent is good within the above carbon number range.
In addition, in the alkylene group of X ″ or the alkyl group of Y ″ and Z ″, as the number of hydrogen atoms substituted with fluorine atoms increases, the strength of the acid increases, and high-energy light or electron beam of 200 nm or less This is preferable because the transparency to the surface is improved.
The proportion of fluorine atoms in the alkylene group or alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all hydrogen atoms are substituted with fluorine atoms. A perfluoroalkylene group or a perfluoroalkyl group.

As the onium salt-based acid generator, in the general formula (b-1) or (b-2), anion ^{- a, R h -COO (R 4 "} SO 3) - [ wherein, ^{R h} Is an alkyl group or a fluorinated alkyl group.] An onium salt-based acid generator substituted with a cation moiety can also be used (the cation moiety is the same as the cation moiety in the formula (b-1) or (b-2)).
In the above formula, examples of R ^h include the same as R ⁴ ″.
Specific examples of the “R ^h —COO ⁻ ” include trifluoroacetate ions, acetate ions, 1-adamantanecarboxylate ions and the like.

  Moreover, the sulfonium salt which has the cation represented by the said Formula (c-3) or (c-4) in a cation part as an onium salt type acid generator can also be used.

The anion part of the sulfonium salt having cations represented by the formulas (c-3) to (c-4) in the cation part is not particularly limited, It may be similar. Examples of the anion moiety include fluorinated alkyl sulfonate ions such as the anion moiety (R ⁴ ″ SO ₃ ⁻ ) of the onium salt acid generator represented by the general formula (b-1) or (b-2). An anion represented by the general formula (b-3) or (b-4), an anion represented by any one of the formulas (b1) to (b8), and the like.

  In this specification, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (B-1), and has a property of generating an acid upon irradiation (exposure) of radiation. It is what you have. Such oxime sulfonate-based acid generators are frequently used for chemically amplified resist compositions, and can be arbitrarily selected and used.

（式（Ｂ−１）中、Ｒ^３１、Ｒ^３２はそれぞれ独立に有機基を表す。）

(In formula (B-1), R ³¹ and R ³² each independently represents an organic group.)

The organic groups of R ³¹ and R ³² are groups containing carbon atoms, and atoms other than carbon atoms (for example, hydrogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms (fluorine atoms, chlorine atoms, etc.), etc.) You may have.
As the organic group for R ^31, a linear, branched, or cyclic alkyl group or aryl group is preferable. These alkyl groups and aryl groups may have a substituent. There is no restriction | limiting in particular as this substituent, For example, a fluorine atom, a C1-C6 linear, branched or cyclic alkyl group etc. are mentioned. Here, “having a substituent” means that part or all of the hydrogen atoms of the alkyl group or aryl group are substituted with a substituent.
As an alkyl group, C1-C20 is preferable, C1-C10 is more preferable, C1-C8 is more preferable, C1-C6 is especially preferable, and C1-C4 is the most preferable. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable. The partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated alkyl group means that all of the hydrogen atoms are halogen atoms. Means an alkyl group substituted with Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.
The aryl group preferably has 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferable. The partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated aryl group means that all of the hydrogen atoms are halogen atoms. Means an aryl group substituted with.
R ³¹ is particularly preferably an alkyl group having 1 to 4 carbon atoms having no substituent or a fluorinated alkyl group having 1 to 4 carbon atoms.
As the organic group for R ^32, a linear, branched, or cyclic alkyl group, aryl group, or cyano group is preferable. As the alkyl group and aryl group for R ^32, the same alkyl groups and aryl groups as those described above for R ³¹ can be used.
R ³² is particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms having no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

  More preferable examples of the oxime sulfonate-based acid generator include compounds represented by the following general formula (B-2) or (B-3).

［式（Ｂ−２）中、Ｒ^３３は、シアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３４はアリール基である。Ｒ^３５は置換基を有さないアルキル基またはハロゲン化アルキル基である。］

[In Formula (B-2), R ³³ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁴ is an aryl group. R ³⁵ represents an alkyl group having no substituent or a halogenated alkyl group. ]

［式（Ｂ−３）中、Ｒ^３６はシアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３７は２または３価の芳香族炭化水素基である。Ｒ^３８は置換基を有さないアルキル基またはハロゲン化アルキル基である。ｐ”は２または３である。］

[In Formula (B-3), R ³⁶ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁷ is a divalent or trivalent aromatic hydrocarbon group. ^R38 is an alkyl group having no substituent or a halogenated alkyl group. p ″ is 2 or 3.]

In the general formula (B-2), the alkyl group or halogenated alkyl group having no substituent of R ³³ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and carbon atoms. Numbers 1 to 6 are most preferable.
R ³³ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³³ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred.
As the aryl group of R ³⁴ , one hydrogen atom is removed from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, or a phenanthryl group. And a heteroaryl group in which a part of carbon atoms constituting the ring of these groups is substituted with a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Among these, a fluorenyl group is preferable.
The aryl group of R ³⁴ may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group, or an alkoxy group. The alkyl group or halogenated alkyl group in the substituent preferably has 1 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms. The halogenated alkyl group is preferably a fluorinated alkyl group.
The alkyl group or halogenated alkyl group having no substituent of R ³⁵ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 6 carbon atoms.
R ³⁵ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³⁵ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred is the strength of the acid generated. Most preferably, it is a fully fluorinated alkyl group in which a hydrogen atom is 100% fluorine-substituted.

In the general formula (B-3), the alkyl group or halogenated alkyl group having no substituent for R ³⁶ is the same as the alkyl group or halogenated alkyl group having no substituent for R ^33. Is mentioned.
Examples of the divalent or trivalent aromatic hydrocarbon group for R ³⁷ include groups obtained by further removing one or two hydrogen atoms from the aryl group for R ³⁴ .
Examples of the alkyl group or halogenated alkyl group having no substituent of R ³⁸ include the same alkyl groups or halogenated alkyl groups as those having no substituent of R ³⁵ .
p ″ is preferably 2.

Specific examples of the oxime sulfonate acid generator include α- (p-toluenesulfonyloxyimino) -benzyl cyanide, α- (p-chlorobenzenesulfonyloxyimino) -benzyl cyanide, α- (4-nitrobenzenesulfonyloxy). Imino) -benzylcyanide, α- (4-nitro-2-trifluoromethylbenzenesulfonyloxyimino) -benzylcyanide, α- (benzenesulfonyloxyimino) -4-chlorobenzylcyanide, α- (benzenesulfonyl) Oxyimino) -2,4-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -2,6-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -4-methoxybenzyl cyanide, α- ( 2-Chlorobenzenesulfonyloxyimino) 4-methoxybenzylcyanide, α- (benzenesulfonyloxyimino) -thien-2-ylacetonitrile, α- (4-dodecylbenzenesulfonyloxyimino) -benzylcyanide, α-[(p-toluenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α-[(dodecylbenzenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α- (tosyloxyimino) -4-thienyl cyanide, α- (methylsulfonyloxyimino) -1-cyclo Pentenyl acetonitrile, α- (methylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -1-cycloheptenylacetonitrile, α- (methylsulfonyloxyimino) -1-cyclooctene Acetonitrile, α- (trifluoromethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -cyclohexylacetonitrile, α- (ethylsulfonyloxyimino) -ethylacetonitrile, α- (propyl Sulfonyloxyimino) -propylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclopentylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclohexylacetonitrile, α- (cyclohexylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- ( Ethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclope Nthenyl acetonitrile, α- (n-butylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (ethylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclohexenylacetonitrile , Α- (n-butylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -phenylacetonitrile, α- (methylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (trifluoro Methylsulfonyloxyimino) -phenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -p- Butoxy phenylacetonitrile, alpha-(propylsulfonyl oxyimino)-p-methylphenyl acetonitrile, alpha-like (methylsulfonyloxyimino)-p-bromophenyl acetonitrile.
Further, an oxime sulfonate-based acid generator disclosed in JP-A-9-208554 (paragraphs [0012] to [0014] [chemical formula 18] to [chemical formula 19]), pamphlet of International Publication No. 04/074242, An oxime sulfonate-based acid generator disclosed in Examples 1 to 40) on pages 65 to 85 can also be suitably used.
Moreover, the following can be illustrated as a suitable thing.

Among diazomethane acid generators, specific examples of bisalkyl or bisarylsulfonyldiazomethanes include bis (isopropylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, Examples include bis (cyclohexylsulfonyl) diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane, and the like.
Further, diazomethane acid generators disclosed in JP-A-11-035551, JP-A-11-035552, and JP-A-11-035573 can also be suitably used.
Examples of poly (bissulfonyl) diazomethanes include 1,3-bis (phenylsulfonyldiazomethylsulfonyl) propane and 1,4-bis (phenylsulfonyldiazo) disclosed in JP-A-11-322707. Methylsulfonyl) butane, 1,6-bis (phenylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (phenylsulfonyldiazomethylsulfonyl) decane, 1,2-bis (cyclohexylsulfonyldiazomethylsulfonyl) ethane, 1,3 -Bis (cyclohexylsulfonyldiazomethylsulfonyl) propane, 1,6-bis (cyclohexylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (cyclohexylsulfonyldiazomethylsulfonyl) decane, etc. Door can be.

As the component (B), one type of acid generator described above may be used alone, or two or more types may be used in combination.
0.5-60 mass parts is preferable with respect to 100 mass parts of (A) component, as for content of (B) component in the resist composition of this invention, 1-50 mass parts is more preferable, 1-40 mass parts Is more preferable. By forming the content of the component (B) within the above range, pattern formation is sufficiently performed. Moreover, when each component of a resist composition is melt | dissolved in the organic solvent, since a uniform solution is obtained and storage stability becomes favorable, it is preferable.

[(D) component]
In the resist composition of the present invention, a nitrogen-containing organic compound component (D) (hereinafter referred to as “(D)” which does not fall under the components (A) and (B), as long as the effects of the present invention are not impaired. Component ")).
As the component (D), an acid diffusion control agent, that is, the component (A) (structural unit (a0)) or the component (A) (structural unit (a0)) and the component (B) is generated by exposure. There is no particular limitation as long as it acts as a quencher for trapping acid, and a wide variety of those have already been proposed. Examples thereof include amines such as aliphatic amines and aromatic amines, among which aliphatic amines, particularly secondary aliphatic amines and tertiary aliphatic amines are preferred.
An aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic groups preferably have 1 to 20 carbon atoms.
Examples of the aliphatic amine include amines (alkyl amines or alkyl alcohol amines) or cyclic amines in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or hydroxyalkyl group having 1 to 20 carbon atoms. It is done.
The alkyl group and the alkyl group in the hydroxyalkyl group may be linear, branched or cyclic.
When the alkyl group is linear or branched, the carbon number thereof is more preferably 2-20, and further preferably 2-8.
When the alkyl group is cyclic (when it is a cycloalkyl group), the carbon number is preferably 3 to 30, more preferably 3 to 20, still more preferably 3 to 15, and 4 to 12 carbon atoms. It is particularly preferred that the number of carbon atoms is 5-10. The alkyl group may be monocyclic or polycyclic. Specific examples include groups in which one or more hydrogen atoms have been removed from monocycloalkane, groups in which one or more hydrogen atoms have been removed from polycycloalkanes such as bicycloalkane, tricycloalkane, and tetracycloalkane. . Specific examples of the monocycloalkane include cyclopentane and cyclohexane. Specific examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
Specific examples of the alkylamine include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; diethylamine, di-n-propylamine, di-n- Dialkylamines such as heptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri- Examples include trialkylamines such as n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decanylamine, and tri-n-dodecylamine.
Specific examples of the alkyl alcohol amine include diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, tri-n-octanolamine, stearyl diethanolamine, lauryldiethanolamine and the like.
Examples of the cyclic amine include heterocyclic compounds containing a nitrogen atom as a hetero atom. The heterocyclic compound may be monocyclic (aliphatic monocyclic amine) or polycyclic (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
As the aliphatic polycyclic amine, those having 6 to 10 carbon atoms are preferable. Specifically, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5. 4.0] -7-undecene, hexamethylenetetramine, 1,4-diazabicyclo [2.2.2] octane, and the like.
Other aliphatic amines include tris (2-methoxymethoxyethyl) amine, tris {2- (2-methoxyethoxy) ethyl} amine, tris {2- (2-methoxyethoxymethoxy) ethyl} amine, tris {2- (1-methoxyethoxy) ethyl} amine, tris {2- (1-ethoxyethoxy) ethyl} amine, tris {2- (1-ethoxypropoxy) ethyl} amine, tris [2- {2- (2-hydroxyethoxy) ) Ethoxy} ethyl] amine and the like.
Examples of the aromatic amine include aniline, pyridine, 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, diphenylamine, triphenylamine, and tribenzylamine.
These may be used alone or in combination of two or more.
(D) component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component. By setting the content in the above range, the resist pattern shape, the stability over time, and the like are improved.

[(E) component]
The resist composition of the present invention is a group consisting of organic carboxylic acid, phosphorus oxo acid and derivatives thereof as optional components for the purpose of preventing sensitivity deterioration and improving the resist pattern shape, retention stability over time, etc. May contain at least one compound (E) (hereinafter referred to as “component (E)”) selected from:
As the organic carboxylic acid, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.
Examples of phosphorus oxo acids include phosphoric acid, phosphonic acid, and phosphinic acid. Among these, phosphonic acid is particularly preferable.
Examples of the oxo acid derivative of phosphorus include esters in which the hydrogen atom of the oxo acid is substituted with a hydrocarbon group, and the hydrocarbon group includes an alkyl group having 1 to 5 carbon atoms and 6 to 6 carbon atoms. 15 aryl groups and the like.
Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphate and diphenyl phosphate.
Examples of phosphonic acid derivatives include phosphonic acid esters such as phosphonic acid dimethyl ester, phosphonic acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, and phosphonic acid dibenzyl ester.
Examples of phosphinic acid derivatives include phenylphosphinic acid and phosphinic acid esters.
(E) A component may be used individually by 1 type and may use 2 or more types together.
(E) A component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.

[(F) component]
The resist composition of the present invention may contain a fluorine additive (hereinafter referred to as “component (F)”) in order to impart water repellency to the resist film. By further containing the component (F), the hydrophobicity of the resist film surface is increased and the occurrence of defects after development is further suppressed.
As the component (F), for example, a fluorine-containing polymer compound described in JP 2010-002870 A can be used.
Specific examples of the component (F) include a copolymer having a structural unit represented by the following general formula (f1). More specifically, a polymer (homopolymer) consisting only of a structural unit represented by the following formula (f1), a copolymer of the structural unit represented by the following formula (f1) and the structural unit (a1) A copolymer of a structural unit represented by the following formula (f1), a structural unit derived from acrylic acid or methacrylic acid, and the structural unit (a1) is preferable.
Among the structural units (a1), the structural unit represented by the formula (a1-1-32) is particularly preferable.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基であり、Ｒ^７”はフッ素原子を含む有機基であり、Ｒ^８”は置換基を有していてもよい炭素数１〜５のアルキレン基である。］

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, R ⁷ ″ is an organic group containing a fluorine atom, and R ⁸ ″ is a substituent. It is a C1-C5 alkylene group which may have. ]

In the formula (f1), R ⁷ ″ is an organic group containing a fluorine atom, preferably a hydrocarbon group containing a fluorine atom. The hydrocarbon group containing a fluorine atom is more preferably a fluorinated alkyl group. Further, a fluorinated alkyl group having 1 to 5 carbon atoms is more preferable. Among them, as R ⁷ ″, a group represented by “— (CH ₂ ) o—CF ₃ ” is preferable (wherein, o is CH _2). Is an integer of 1 to 3).
In formula (f1), the carbon number of the alkylene group of R ⁸ ″ is 1 to 5, preferably 1 to 3, and more preferably 1 or 2. The hydrogen atom of the alkylene group of R ⁸ ″. May be substituted with a fluorine atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms.
In the formula (f1), R is the same as described above. R is preferably a hydrogen atom or a methyl group.
(F) A component may be used individually by 1 type and may use 2 or more types together.
The content of the component (F) in the resist composition is preferably 1 to 10 parts by mass per 100 parts by mass of the component (A). By making content of (F) component into the said range, the hydrophobicity of the resist film surface increases, and the defect generation after image development is suppressed more.

  The resist composition of the present invention may further contain, if desired, miscible additives such as an additional resin for improving the performance of the resist film, a surfactant for improving coatability, a dissolution inhibitor, Plasticizers, stabilizers, colorants, antihalation agents, dyes, and the like can be added and contained as appropriate.

[(S) component]
The resist composition of the present invention can be produced by dissolving the material in an organic solvent (hereinafter sometimes referred to as “(S) component”).
As the component (S), any component can be used as long as it can dissolve each component to be used to form a uniform solution. Conventionally, any one of known solvents for chemically amplified resists can be used. Two or more types can be appropriately selected and used.
For example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; Monohydric alcohols; compounds having an ester bond, such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, monomethyl ether, monoethyl of the polyhydric alcohols or compound having the ester bond Ether alkyl such as ether, monopropyl ether, monobutyl ether or monophenyl ether Derivatives of polyhydric alcohols such as compounds having a propylene glycol monomethyl ether acetate (PGMEA) or propylene glycol monomethyl ether (PGME) among these]; cyclic ethers such as dioxane, methyl lactate, Esters such as ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, Aromatic organics such as dibenzyl ether, phenetol, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene A solvent etc. can be mentioned.
These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
Among these, γ-butyrolactone, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), cyclohexanone, and EL are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range. For example, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3. Further, when PGME and cyclohexanone are blended as polar solvents, the mass ratio of PGMEA: (PGME + cyclohexanone) is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2, and even more preferably 3. : 7 to 7: 3.
In addition, as the component (S), PGMEA, EL or a mixed solvent of PGMEA and a polar solvent and a mixed solvent of γ-butyrolactone are also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.
The amount of the component (S) used is not particularly limited and is a concentration that can be applied to a substrate or the like, and is appropriately set according to the coating film thickness. Generally, the solid content concentration of the resist composition is It is used in a range of 1 to 20% by mass, preferably 2 to 15% by mass.

≪Resist pattern formation method≫
The resist pattern forming method of the present invention includes a step of forming a resist film on a support using the resist composition of the present invention, a step of exposing the resist film, and developing the resist film to form a resist pattern. Forming.
The resist pattern forming method of the present invention can be performed, for example, as follows.
That is, first, the resist composition of the present invention is applied onto a support with a spinner or the like, and a baking (post-apply bake (PAB)) treatment is performed, for example, at a temperature of 80 to 150 ° C. for 40 to 120 seconds, preferably A resist film is formed by applying for 60 to 90 seconds.
Next, the resist film is exposed through a mask (mask pattern) on which a predetermined pattern is formed using an exposure apparatus such as an ArF exposure apparatus, an electron beam drawing apparatus, or an EUV exposure apparatus, or a mask pattern. After performing selective exposure by drawing or the like by direct irradiation with an electron beam without passing through, baking (post-exposure baking (PEB)) treatment is performed, for example, at a temperature of 80 to 150 ° C. for 40 to 120 seconds, preferably 60 Apply for ~ 90 seconds.
Next, the resist film is developed.
The development treatment is performed using an alkaline developer in the case of an alkali development process, and using a developer (organic developer) containing an organic solvent in the case of a solvent development process.
A rinsing treatment is preferably performed after the development treatment. The rinse treatment is preferably a water rinse using pure water in the case of an alkali development process, and is preferably a rinse solution containing an organic solvent in the case of a solvent development process.
In the case of a solvent development process, after the development process or the rinse process, a process of removing the developer or rinse liquid adhering to the pattern with a supercritical fluid may be performed.
Drying is performed after development or rinsing. In some cases, a baking process (post-bake) may be performed after the development process. In this way, a resist pattern can be obtained.

The support is not particularly limited, and a conventionally known one can be used, and examples thereof include a substrate for electronic components and a substrate on which a predetermined wiring pattern is formed. More specifically, a silicon substrate, a metal substrate such as copper, chromium, iron, and aluminum, a glass substrate, and the like can be given. As a material for the wiring pattern, for example, copper, aluminum, nickel, gold or the like can be used.
Further, the support may be a substrate in which an inorganic and / or organic film is provided on the above-described substrate. An inorganic antireflection film (inorganic BARC) is an example of the inorganic film. Examples of the organic film include organic films such as an organic antireflection film (organic BARC) and a lower organic film in a multilayer resist method.
Here, the multilayer resist method is a method in which at least one organic film (lower organic film) and at least one resist film (upper resist film) are provided on a substrate, and the resist pattern formed on the upper resist film is used as a mask. This is a method of patterning a lower organic film, and it is said that a pattern with a high aspect ratio can be formed. That is, according to the multilayer resist method, the required thickness can be secured by the lower organic film, so that the resist film can be thinned and a fine pattern with a high aspect ratio can be formed.
In the multilayer resist method, basically, a method of forming a two-layer structure of an upper resist film and a lower organic film (two-layer resist method), and one or more intermediate layers between the upper resist film and the lower organic film And a method of forming a multilayer structure of three or more layers (metal thin film etc.) (three-layer resist method).

The wavelength used for the exposure is not particularly limited, and ArF excimer laser, KrF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. Can be done using radiation. The resist composition is highly useful for KrF excimer laser, ArF excimer laser, EB or EUV.

The exposure method of the resist film may be normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or may be immersion exposure (Liquid Immersion Lithography).
In immersion exposure, the space between the resist film and the lens at the lowest position of the exposure apparatus is previously filled with a solvent (immersion medium) having a refractive index larger than that of air, and exposure (immersion exposure) is performed in that state. It is an exposure method.
As the immersion medium, a solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film to be exposed is preferable. The refractive index of such a solvent is not particularly limited as long as it is within the above range.
Examples of the solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicon-based solvent, and a hydrocarbon-based solvent.
Specific examples of the fluorine-based inert liquid include a fluorine-based compound such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , and C ₅ H ₃ F ₇ as a main component. Examples thereof include liquids, and those having a boiling point of 70 to 180 ° C are preferable, and those having a boiling point of 80 to 160 ° C are more preferable. It is preferable that the fluorine-based inert liquid has a boiling point in the above range since the medium used for immersion can be removed by a simple method after the exposure is completed.
As the fluorine-based inert liquid, a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms is particularly preferable. Specific examples of the perfluoroalkyl compound include a perfluoroalkyl ether compound and a perfluoroalkylamine compound.
More specifically, examples of the perfluoroalkyl ether compound include perfluoro (2-butyl-tetrahydrofuran) (boiling point: 102 ° C.). Examples of the perfluoroalkylamine compound include perfluorotributylamine ( Boiling point of 174 ° C.).
As the immersion medium, water is preferably used from the viewpoints of cost, safety, environmental problems, versatility, and the like.

Examples of the alkali developer used for the development treatment in the alkali development process include a 0.1 to 10% by mass tetramethylammonium hydroxide (TMAH) aqueous solution.
The organic solvent contained in the organic developer used for the development process in the solvent development process is not particularly limited as long as it can dissolve the component (A) (component (A) before exposure). It can be selected as appropriate. Specifically, polar solvents such as ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents, and hydrocarbon solvents can be used.
A known additive can be blended in the organic developer as required. Examples of the additive include a surfactant. The surfactant is not particularly limited. For example, ionic or nonionic fluorine-based and / or silicon-based surfactants can be used.
When the surfactant is blended, the blending amount is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and 0.01 to 0. 0% with respect to the total amount of the organic developer. 5 mass% is more preferable.
The development process can be carried out by a known development method, for example, a method in which a support is immersed in a developer for a certain period of time (dip method), a developer is raised on the surface of the support by surface tension, and is left for a certain period of time. (Paddle method), spraying developer on the surface of the support (spray method), coating the developer while scanning the developer coating nozzle at a constant speed on the support rotating at a constant speed The method to continue (dynamic dispensing method) etc. are mentioned.

As the organic solvent contained in the rinsing liquid used for the rinsing treatment after the development process in the solvent development process, for example, among the organic solvents mentioned as the organic solvent contained in the organic developer, those that are difficult to dissolve the resist pattern are appropriately used. You can select and use. Usually, at least one solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents and ether solvents is used. Among these, at least one selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents and amide solvents is preferable, and at least one selected from alcohol solvents and ester solvents is preferable. More preferred are alcohol solvents.
The rinse treatment (washing treatment) using the rinse liquid can be performed by a known rinse method. Examples of the method include a method of continuously applying a rinsing liquid on a support rotating at a constant speed (rotary coating method), a method of immersing the support in a rinsing liquid for a predetermined time (dip method), and the surface of the support. And a method of spraying a rinse liquid (spray method).

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.
In this example, the compound represented by the chemical formula (1) is described as “compound (1)”, and the compounds represented by other chemical formulas are also described in the same manner.
In the analysis by NMR, the internal standard of ¹ H-NMR and the internal standard of ¹³ C-NMR is tetramethylsilane (TMS).

[Example 1: Production of polymer compound 2]
In a separable flask connected with a thermometer, a reflux tube, and a nitrogen introduction tube, 38.00 g (120.13 mmol) of compound (1), 61.10 g (232.84 mmol) of compound (2), 18.25 g (37 .05 mmol) of the compound (3) was dissolved in 147.76 g of a mixed solution of methyl ethyl ketone / cyclohexanone (MEK / CH). To this solution, 27.30 mmol of dimethyl azobisisobutyrate (V-601) as a polymerization initiator was added and dissolved.
This was added dropwise to 81.79 g of MEK / CH over 4 hours under a nitrogen atmosphere. After completion of dropping, the reaction solution was heated and stirred for 1 hour, and then the reaction solution was cooled to room temperature.
The obtained reaction polymerization solution was dropped into a large amount of n-heptane to precipitate a polymer, and the precipitated white powder was filtered, dispersed and washed with methanol, and dried to obtain polymer compound 1 (precursor) Body polymer) was obtained.
76.28 g of the polymer compound 1 was placed in an eggplant flask, 15.10 g of the compound (11), 305 g of MEK and 305 g of water were added and stirred for 30 minutes to extract the organic layer. The extracted organic layer was washed with water, and the solvent was distilled off to obtain 64.84 g of polymer compound 2.
The mass average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement for this polymer compound was 13200, and the molecular weight dispersity (Mw / Mn) was 1.48.
The copolymer composition ratio (ratio of each structural unit in the structural formula (molar ratio)) determined by carbon-13 nuclear magnetic resonance spectrum (600 MHz — 13C-NMR) was 1 / m / n = 45.6 / 40. It was 1 / 14.3.

[Comparative Example 1: Production of Comparative Polymer Compound 2]
In a separable flask connected with a thermometer, a reflux tube, and a nitrogen introduction tube, 18.00 g (56.90 mmol) of compound (1), 28.94 g (110.29 mmol) of compound (2), 9.21 g (17 .55 mmol) of the compound (4) was dissolved in 70.72 g of a mixed solution of methyl ethyl ketone / cyclohexanone (MEK / CH). To this solution, 17.55 mmol of dimethyl azobisisobutyrate (V-601) was added and dissolved as a polymerization initiator.
This was dripped at 39.13g MEK / CH over 4 hours under nitrogen atmosphere. After completion of the dropwise addition, the reaction solution was heated and stirred for 1 hour to produce a white solid.
The white solid was filtered off and analyzed by carbon-13 nuclear magnetic resonance spectrum (600 MHz — 13C-NMR). As a result, deprotection of compound (2) was confirmed, and the desired comparative polymer compound 2 was not obtained. The intended reactions are as follows.

[Example 2: Production of polymer compound 3]
The polymer compound 3 was produced in the same manner as in Example 1 except that the compound (12) was used in an equimolar amount instead of the compound (11). In the following formula, the synthesis of polymer compound 1 is omitted.

［Ｍｗ＝１３７００、Ｍｗ／Ｍｎ＝１．５２，ｌ／ｍ／ｎ＝４６．２／３９．３／１４．５］

[Mw = 13700, Mw / Mn = 1.52, 1 / m / n = 46.2 / 39.3 / 14.5]

[Comparative Example 2: Production of Comparative Polymer Compound 3]
Comparative polymer compound 3 was produced in the same manner as in comparative example 1 except that compound (5) was used in an equimolar amount instead of compound (4), but the desired comparative polymer compound 3 was obtained. There wasn't. The intended reactions are as follows.

[Example 3: Production of polymer compound 4]
In a separable flask connected with a thermometer, a reflux tube, and a nitrogen introduction tube, 38.00 g (120.13 mmol) of compound (1), 61.10 g (232.84 mmol) of compound (2), 26.93 g (37 .05 mmol) of the compound (3) was dissolved in 158.91 g of a mixed solution of methyl ethyl ketone / cyclohexanone (MEK / CH). To this solution, 27.30 mmol of dimethyl azobisisobutyrate (V-601) as a polymerization initiator was added and dissolved.
This was dripped at 87.83g MEK / CH over 4 hours in nitrogen atmosphere. After completion of dropping, the reaction solution was heated and stirred for 1 hour, and then the reaction solution was cooled to room temperature.
The obtained reaction polymerization solution was dropped into a large amount of n-heptane to precipitate a polymer, and the precipitated white powder was filtered, dispersed and washed with methanol, and dried to obtain polymer compound 1 (precursor) Body polymer) was obtained.
75.61 g of the polymer compound 1 was placed in an eggplant flask, 16.13 g of the compound (13), 302 g of MEK, and 302 g of water were added and stirred for 30 minutes to extract the organic layer. The extracted organic layer was washed with water and the solvent was distilled off to obtain 54.98 g of polymer compound 4.
The mass average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement for this polymer compound was 13000, and the molecular weight dispersity (Mw / Mn) was 1.53.
The copolymer composition ratio (ratio of each structural unit in the structural formula (molar ratio)) determined by carbon-13 nuclear magnetic resonance spectrum (600 MHz — 13C-NMR) was 1 / m / n = 46.3 / 39. 9 / 13.8.

[Comparative Example 3: Production of Comparative Polymer Compound 4]
In a separable flask connected with a thermometer, a reflux tube, and a nitrogen introduction tube, 18.00 g (56.90 mmol) of compound (1), 28.94 g (110.29 mmol) of compound (2), 12.75 g (17 .55 mmol) of compound (6) was dissolved in 75.27 g of a mixed solution of methyl ethyl ketone / cyclohexanone (MEK / CH). To this solution, 12.93 mmol of dimethyl azobisisobutyrate (V-601) was added and dissolved as a polymerization initiator.
This was dripped at 41.61 g of MEK / CH over 4 hours under a nitrogen atmosphere. After completion of dropping, the reaction solution was heated and stirred for 1 hour, and then the reaction solution was cooled to room temperature.
The obtained reaction polymerization solution was dropped into a large amount of n-heptane, and a polymer was precipitated. The precipitated white powder was filtered, dispersed and washed with methanol, and dried to give comparative polymer compound 4. 37.95 g was obtained.
The mass average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement for this polymer compound was 12200, and the molecular weight dispersity (Mw / Mn) was 1.70.
The copolymer composition ratio (ratio of each structural unit in the structural formula (molar ratio)) determined by carbon-13 nuclear magnetic resonance spectrum (600 MHz — 13C-NMR) was 1 / m / n = 46.2 / 41. It was 4 / 12.4.

[Examples 4 to 6: Production of polymer compounds 5 to 7]
Polymer compounds 5 to 7 were produced in the same manner as in Example 1 except that the compounds (14) to (16) were used in equimolar amounts instead of the compound (11). In the following formula, the synthesis of polymer compound 1 is omitted.

［Ｍｗ＝１３８００、Ｍｗ／Ｍｎ＝１．５２、ｌ／ｍ／ｎ（モル比）＝４６．４／４０．５／１３．１］

[Mw = 13800, Mw / Mn = 1.52, 1 / m / n (molar ratio) = 46.4 / 40.5 / 13.1]

［Ｍｗ＝１３３００、Ｍｗ／Ｍｎ＝１．５０、ｌ／ｍ／ｎ（モル比）＝４６．７／４０．５／１２．８］

[Mw = 13300, Mw / Mn = 1.50, 1 / m / n (molar ratio) = 46.7 / 40.5 / 12.8]

［Ｍｗ＝１３７００、Ｍｗ／Ｍｎ＝１．５５、ｌ／ｍ／ｎ＝４５．８／３９．５／１４．７］

[Mw = 13700, Mw / Mn = 1.55, 1 / m / n = 45.8 / 39.5 / 14.7]

[Comparative Examples 4-6: Production of Comparative Polymer Compounds 5-7]
Comparative polymer compound 3 was produced in the same manner as in Comparative Example 1 except that compounds (7) to (9) were used in equimolar amounts instead of compound (4). The target polymer compound was produced. The intended reactions are as follows.

［Ｍｗ＝１１９００、Ｍｗ／Ｍｎ＝１．８１、ｌ／ｍ／ｎ＝４４．８／４２．２／１３．０］

[Mw = 1900, Mw / Mn = 1.81, 1 / m / n = 44.8 / 42.2 / 13.0]

［Ｍｗ＝１２７００、Ｍｗ／Ｍｎ＝１．６８、ｌ／ｍ／ｎ＝４５．９／４０.７／１３．４］

[Mw = 1700, Mw / Mn = 1.68, 1 / m / n = 45.9 / 40.7 / 13.4]

[Examples 7 to 12, Comparative Examples 7 to 12]
A resist composition was prepared using the polymer compounds produced in Examples 1 to 6 and Comparative Examples 1 to 6, and after forming a resist pattern, the exposure margin, roughness and shape were evaluated. . Table 1 shows the polymer compound used, the amount of residual monomer in the polymer compound, the sensitivity during pattern formation, and the evaluation results. The comparative polymer compounds 2, 3 and 7 for which the polymer compound could not be produced are described in Table 1 as “Unable to synthesize”.
Table 1 shows the results (retention times) obtained by measuring the hydrophobicity of the cations (polymeric cations derived from the second sulfonium or iodonium cations in the examples) used in each example by HPLC. Also described. In addition, the retention time of the cation in the compound (3) and the polymer compound 1 is 2.7 minutes.
The composition of the resist composition, the pattern formation method, and the evaluation method will be described later.

From the above results, it was confirmed that according to the production method of the present invention, it is possible to produce a polymer compound that generates an acid by various exposures.
Moreover, it is clear that the amount of residual monomers of the polymer compounds 2 to 7 obtained by the production method of the present invention is reduced as compared with the polymer compound of the comparative example. The comparative polymer compounds 4 to 6 used in Comparative Examples 9 to 11 and the precursor polymers of the polymer compounds 4 to 6 used in Examples 9 to 11 are all subjected to the same dispersion cleaning with methanol. However, it can be seen that the residual monomer reduction efficiency is much better in the examples. And the resist composition of Examples 7-12 using the high molecular compounds 2-7 of an Example is excellent in lithography characteristics and pattern shapes, such as exposure margin and roughness, compared with the resist composition of a comparative example. Was confirmed.

<Measurement of hydrophobicity of cations>
The degree of hydrophobicity of the cation was measured by HPLC measurement under the following conditions.
Eluent (developing solvent): acetonitrile / buffer solution (50/50 volume ratio)
Buffer solution: trifluoroacetic acid / ion exchange water (0.1% by mass).
Apparatus: Dionex U3000 (manufactured by Dionex).
Column: Superiorex-ODX (manufactured by Shiseido Co., Ltd.).
Detector: Corona CAD (manufactured by ESA Biosciences).
Flow rate: 1 mL / min.
Column temperature: 30 ° C
Sample concentration: acetonitrile solution with a solid content of 0.1% by mass Injection volume: 2 μl
The sample concentration indicates the solid content concentration of a compound in which the anion is Br ⁻ and the cation has various target structures.

<Preparation of resist composition>
The resist composition was prepared by mixing and dissolving the following components in the amounts shown in [].
(A) Component: Each polymer compound shown in Table 1 [100 parts by mass].
Component (D): tri-n-octylamine [1.6 parts by mass].
Component (E): salicylic acid [0.64 parts by mass].
(S) Component (1): γ-butyrolactone [200 parts by mass].
(S) Component (2): PGMEA / PGME / cyclohexanone = 30/20/50 (mass ratio) mixed solvent [4160 parts by mass].

<Measurement of residual monomer amount>
The amount of residual monomer was measured by the following procedure.
Procedure 1: HPLC measurement was carried out on solutions of different concentrations (5 points) in which compound (3) was dissolved in γ-butyrolactone, and a calibration curve was prepared to determine “HPLC area and concentration of water-soluble monomer”. The relational expression was obtained.
Procedure 2: For each example, the obtained compound (salt polymer 1) before salt exchange and for the comparative example, finally obtained compounds (comparative polymer compounds 2 to 7) are respectively γ-butyrolactone. 1% by mass solution was prepared.
Procedure 3: HPLC measurement was performed on the solution having a concentration of 1% by mass under the following conditions, and the residual monomer amount (% by mass) relative to the solid content of the polymer compound was calculated from the above relational expression. The result was defined as “residual monomer amount (ppm)”.

The HPLC measurement was performed under the following measurement conditions.
[HPLC measurement conditions]
Eluent (developing solvent): acetonitrile / buffer solution (80/20 volume ratio),
Buffer solution: trifluoroacetic acid / ion exchange water (0.1% by mass),
Column: Superiorex-ODS,
Oven temperature: 30 ° C
Measurement wavelength: 210 nm,
Flow rate: 1 mL / min (up to 7 minutes) 3 mL / min (up to 20 minutes).
The mixing ratio of the developing solvent for HPLC was appropriately changed between acetonitrile / buffer solution = 90 / 10-30 / 70 volume ratio depending on the type of water-soluble monomer used.

<Formation of resist pattern>
Each resist composition was uniformly applied using a spinner on an 8-inch silicon substrate that had been subjected to hexamethyldisilazane (HMDS) treatment at 90 ° C. for 36 seconds, and baked at 140 ° C. for 60 seconds. (PAB) was performed to form a resist film (film thickness 60 nm).
The resist film was drawn (exposed) at an acceleration voltage of 50 keV using an electron beam drawing machine HL800D (VSB) (manufactured by Hitachi).
Next, baking treatment (post-exposure PEB) was performed at 110 ° C. for 60 seconds, and a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) (trade name: NMD-3, Tokyo Ohka Kogyo Co., Ltd.) at 23 ° C. For 60 seconds.
As a result, in each example, a line-and-space resist pattern (hereinafter referred to as “LS pattern”) having a line width of 100 nm and a pitch of 200 nm was formed. In addition, the optimum exposure dose Eop (μC / cm ² ; sensitivity) at which the LS pattern was formed was determined.

<Evaluation of exposure margin (EL margin)>
The exposure amount when the line of the LS pattern is formed within the range of ± 5% (95 nm to 105 nm) of the target dimension (space width 100 nm) with the optimum exposure amount Eop is obtained, and the EL margin (unit:%) is obtained by the following equation. )
EL margin (%) = (| E1-E2 | / Eop) × 100
E1: Exposure amount (mJ / cm ² ) when an LS pattern having a line width of 95 nm was formed
E2: exposure amount (mJ / cm ² ) when an LS pattern having a line width of 105 nm was formed
Note that the larger the value of the EL margin, the smaller the change amount of the pattern size accompanying the change in the exposure amount.

<Evaluation of line edge roughness (LER)>
With respect to the LS pattern formed with the optimum exposure amount Eop, 3σ, which is a scale indicating LER, was obtained.
“3σ” is a length measurement SEM (scanning electron microscope, acceleration voltage 800 V, trade name: S-9380, manufactured by Hitachi High-Technologies Corporation), and the line width was measured at 400 points in the longitudinal direction of the line. It means a triple value (3 s) (unit: nm) of the obtained standard deviation (σ). The smaller the value of 3s, the smaller the roughness of the line side wall, which means that an LS pattern having a more uniform width was obtained.

<Pattern shape evaluation>
By observing the cross-sectional shape of the LS pattern formed at the optimum exposure amount Eop using a scanning electron microscope (trade name: SU-8000, manufactured by Hitachi High-Technology Corporation), the resist pattern shape is determined according to the following criteria. evaluated.
○: The rectangularity is high.
X: Top-round shape (shape in which the upper part of the pattern cross section is rounded) and rectangularity is low.

Claims (2)

At least one anion group selected from the group consisting of a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methide anion, and a first sulfonium or iodonium cation A method for producing a polymer compound comprising polymerizing a monomer having a precursor polymer, washing, and then salt-exchanging the precursor polymer with a second sulfonium or iodonium cation,
The second sulfonium or iodonium cation is more hydrophobic than the first sulfonium or iodonium cation,
The retention time of the second sulfonium or iodonium cation measured by a high performance liquid chromatography method is measured by a high performance liquid chromatography method under the same conditions as the measurement of the retention time of the second sulfonium or iodonium cation. A method for producing a polymer compound having a structural unit capable of decomposing upon exposure to generate an acid, wherein a value divided by a retention time of the first sulfonium or iodonium cation is 1.05 or more. A combination of the first sulfonium or iodonium cation and the second sulfonium or iodonium cation is
The first sulfonium or iodonium cation is a cation represented by the following formula (c-1-1); and the second sulfonium or iodonium cation is represented by the following formulas (c-1-01) to (c-1- 02), (c-1-03-2), a cation represented by (c-1-8) or (c-1-31), or a combination that is a bis (4-tert-butylphenyl) iodonium cation,
The first sulfonium or iodonium cation is a diphenyliodonium cation; and the second sulfonium or iodonium cation is represented by the following formulas (c-1-1) to (c-1-31), (c-1-01) to The combination of (c-1-04), or the first sulfonium or iodonium cation is a trimethylsulfonium cation or a cation represented by the following formula (c-1-33); the second sulfonium or iodonium cation is The manufacturing method of the high molecular compound of Claim 1 which is the combination which is the following formula (c-1-1)-(c-1-31), (c-1-01)-(c-1-04). .

[Wherein g1 represents the number of repetitions and is an integer of 1 to 5. g2 represents the number of repetitions and is an integer of 0-20. g3 represents the number of repetitions and is an integer of 0-20. u is an integer of 1 to 3. R ^{6a to} R ^8a are an alkylene group which may have a substituent or a phenylene group which may have a substituent. R ^{6b to} R ^8b are a hydrogen atom, an alkyl group which may have a substituent, a phenyl group which may have a substituent, or a naphthyl group. R ⁹ is an alkyl group which may have a substituent, a phenyl group which may have a substituent, or a naphthyl group. ]