JP6887394B2 - Sulfonium salt, photoacid generator, composition containing it, and method for manufacturing device - Google Patents

Description

One aspect of the present invention relates to a novel sulfonium salt. Another aspect of the present invention relates to a photoacid generator containing the sulfonium salt, a composition containing the photoacid generator, and a method for producing a device using the composition.

In semiconductor devices, for example, highly integrated circuit elements typified by DRAM and the like, there is a high demand for higher density, higher integration, or higher speed. Along with this, in various electronic device manufacturing fields, there is an increasing demand for establishment of microfabrication technology on the order of half micron, for example, development of photolithography technology for fine pattern formation.

In photolithography technology, i-line with a wavelength of 365 nm is currently widely used as exposure light. For this reason, a medium-pressure / high-pressure mercury lamp that is inexpensive but exhibits good emission intensity may be used as the irradiation light source. Another example is that LED lamps having an emission wavelength in the i-line region (360 nm to 390 nm) are becoming widespread in recent years. Therefore, a photoacid generator added to a photoresist that is deprotected or crosslinked by the action of an acid, polar-converted to change its solubility in a developing solution, and developed to form a pattern, and cationic polymerization by the action of an acid. Among the photoacid generators added to the resin that is cured by the above, the need for photoacid generators that are highly sensitive to i-rays is expected to increase in the future.

Further, i-line lithography for semiconductors for packaging applications is often used for thick films because, for example, bumps and metal posts are formed by a plating process. Therefore, it is preferable that the sensitivity is high while ensuring high solubility in the resist solvent, but there is a problem in achieving both in terms of synthesis cost.

In addition to adding at least one of an alkyl ketone, an aryl ketone, anthraquinone and a thioxanthone to a sulfonium salt having a phenylsulfanyl group for the purpose of improving the absorption of conventional i-rays among existing photoacid generators. It has been studied to lengthen the wavelength by adding various substituents (Patent Documents 1 to 3). However, all conventional photoacid generators do not absorb sufficiently in the i-ray region, or even when the absorption is large, sulfonium is not directly added to the structure with high i-ray absorption, but is mediated by a phenylsulfanyl group. Therefore, the light utilization efficiency is low and the sensitivity is not sufficient. In addition, by adding a structure with high absorption to multiple i-rays for one sulfonium, the i-ray absorption required for one generated acid increases, which is a disadvantage in the usage method where transmittance is required.

JP 2011-180586 Japanese Unexamined Patent Publication No. 2013-0438664 Japanese Patent Application Laid-Open No. WO2011-052327

In view of such circumstances, it is an object of some aspects of the present invention to provide a sulfonium salt having a thioxanthone skeleton having high absorption in the i-ray region. Another object of the present invention is to provide a photoacid generator containing the sulfonium salt, a composition containing the photoacid generator, and a method for producing a device using the composition. To do.

By introducing a specific substituent at the 3-position of the sulfonium salt having a thioxanthone skeleton, the present inventors have higher absorption in the i-line region than the sulfonium salt having no specific substituent at the 3-position. I found that.

One aspect of the present invention for solving the above problems is a sulfonium salt represented by the following general formula (1) or general formula (2).

In the above formulas (1) and (2), R ¹ and R ² may independently have a substituent, respectively. A linear, branched or cyclic alkyl group having 1 to 12 carbon atoms; A linear, branched or cyclic alkenyl group having 1 to 12 carbon atoms which may have a group; an aryl group having 6 to 14 carbon atoms which may have a substituent; and a substituent. It is any one selected from the group consisting of heteroaryl groups having 4 to 12 carbon atoms which may be used.
At ^{least one methylene group in R 1} and R ² may be substituted with a divalent heteroatom-containing group.
Further, the above R ¹ and R ² form a ring structure together with the sulfur atom to which they are bonded, either directly by a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and a methylene group. You may.

R ³ is a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, each of which may independently have a substituent; and may have a substituent, linear, branched or cyclic. Alkenyl group having 1 to 12 carbon atoms; linear, branched or cyclic alkoxy group having 1 to 12 carbon atoms which may have a substituent ;; the number of carbon atoms which may have a substituent. 1 to 12 aryloxy groups; heteroaryloxy groups having 4 to 12 carbon atoms which may have substituents; linear, branched or cyclic carbon atoms 1 to 12 which may have substituents. Twelve alkylsulfanyl groups; arylsulfanyl groups which may have substituents; heteroarylsulfanyl groups which may have substituents and have 4 to 12 carbon atoms; direct which may have substituents. Chain, branched or cyclic alkylsulfonyl group with 1 to 12 carbon atoms; may have substituents 1 to 12 arylsulfonyl groups; may have substituents 4 carbon atoms ~ 12 heteroarylsulfonyl groups; etc.

Each of R ⁴ and R ⁵ independently has a hydrogen atom; a hydroxy group; a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; a substituent. It may have a linear, branched or cyclic alkenyl group having 1 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and may have a substituent. Heteroaryl group having 4 to 12 carbon atoms ;; branched or cyclic alkylcarbonyloxy group having 1 to 12 carbon atoms; linear or branched which may have a substituent. Alternatively, an alkenylcarbonyloxy group having 1 to 12 cyclic carbon atoms; an arylcarbonyloxy group having 6 to 12 carbon atoms which may have a substituent; and 4 to 4 carbon atoms which may have a substituent. It is one selected from the group consisting of 12 heteroarylcarbonyloxy groups;

R ⁶ is not particularly limited, but has a halogen atom; a hydroxyl group; a nitro group; a linear chain which may have a substituent, and a linear, branched or cyclic carbon atom number 1 which may have a substituent. Alkyl groups of ~ 12; linear, branched or cyclic alkenyl groups having 1 to 12 carbon atoms which may have substituents; aryl groups having 6 to 14 carbon atoms which may have substituents. Heteroaryl group having 4 to 14 carbon atoms which may have a substituent; linear, branched or cyclic alkoxy group having 1 to 12 carbon atoms which may have a substituent; It may have an aryloxy group having 1 to 12 carbon atoms; a linear, branched or cyclic alkylsulfanyl group having 1 to 12 carbon atoms which may have a substituent; and having a substituent. It may have an arylsulfanyl group having 1 to 12 carbon atoms; a linear, branched or cyclic alkylsulfonyl group having 1 to 12 carbon atoms which may have a substituent; and may have a substituent. An arylsulfonyl group having 6 to 12 carbon atoms; and a heteroarylsulfonyl group having 4 to 12 carbon atoms which may have a substituent; a linear, branched or cyclic group which may have a substituent. Alkylcarbonyloxy groups having 1 to 12 carbon atoms; linear, branched or cyclic alkenylcarbonyloxy groups having 1 to 12 carbon atoms which may have substituents; carbons which may have substituents. It is any one selected from the group consisting of an arylcarbonyloxy group having 6 to 12 atoms; a heteroarylcarbonyloxy group having 4 to 12 carbon atoms which may have a substituent;

At ^{least one methylene group in R 4} , R ⁵ and R ⁶ may be substituted with a divalent heteroatom-containing group.
n is an integer from 0 to 4.

^{At least two of R 1 to} R ⁵ described above form a ring structure together with the sulfur atom to which they are bonded, either directly in a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and a methylene group. It may be formed.

In the above formula (1), forming at least two of two or more R ⁶ is directly a single bond or an oxygen atom, a cyclic structure via one selected from the group consisting of a sulfur atom and a methylene group You may.

X- represents a monovalent counter anion.

Another aspect of the present invention is a photoacid generator containing the sulfonium salt.
Another aspect of the present invention is a composition containing the photoacid generator containing the sulfonium salt and an acid-reactive compound.
Further, another aspect of the present invention includes a step of applying the above composition on a substrate to form a resist film.
The step of irradiating the resist film with active energy rays and
This is a method for manufacturing a device including the step of developing the resist film.

According to the present invention, it is possible to provide a sulfonium salt having a thioxanthone skeleton having high absorption in the i-ray region. Further, the sulfonium salt in one embodiment of the present invention has a low content of dimer cations and has high solubility in a specific resist solvent such as ethyl lactate. Thereby, it is possible to provide a method for producing a photoacid generator, a composition, and a device having high sensitivity in the i-ray region.

FIG. 1 shows UV spectra of sulfonium salts used in Examples and Comparative Examples.

Hereinafter, the present invention will be specifically described, but the present invention is not limited thereto.
<1> Sulfonium salt The sulfonium salt according to one aspect of the present invention is represented by the above general formula (1).

Specific examples of the linear alkyl group having 1 to 12 carbon atoms in R ¹ and R ² include a methyl group, an ethyl group, an n-propyl group, an n-butyl group and the like.
Specific examples of the branched alkyl group having 1 to 12 carbon atoms in R ¹ and R ^{2 include an isopropyl group and a t-butyl group.}
Specific examples of the cyclic alkyl group having 1 to 12 carbon atoms in R ¹ and R ² include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an adamantan-1-yl group, and an adamantan-2-yl group. Examples thereof include a norbornan-1-yl group and a norbornan-2-yl group.

When R ¹ and R ² have a methylene group, instead of at least one methylene group, -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-,- CONH-, -NH-CO-O-, -O-CO-NH-, -NH-, -N (R ⁷ )-, -N (Ar ¹ )-, -S-, -SO- and -SO ₂ The skeleton may contain one heteroatom-containing group selected from the group consisting of −. However, it is preferable not to have a continuous connection of the same heteroatoms such as —O— and —SS—.
The hydrogen atom bonded to the nitrogen atom in -NHCO-, -CONH-, -NH-CO-O-, -O-CO-NH-, -NH-, etc. is replaced with ^{R 7} or Ar ^1. Is also good. R ⁷ and Ar ¹ will be described later.
However, it is preferable that the sulfur atom (S ⁺ ) is not directly bonded to the heteroatom-containing group but is bonded to the heteroatom-containing group via a divalent hydrocarbon group such as a methylene group.
Examples of the alkenyl groups of R ¹ and R ² include those in which at least one carbon-carbon single bond of the above alkyl group is replaced with a carbon-carbon double bond.

Specifically, as the aryl group having 6 to 14 carbon atoms of R ¹ and R ² , a monocyclic aromatic hydrocarbon group and a condensed polycyclic aromatic hydrocarbon obtained by condensing at least two rings of the monocyclic aromatic hydrocarbon. Hydrogen groups and the like can be mentioned. These aryl groups may have a substituent.
Examples of the monocyclic aromatic hydrocarbon group include a phenyl group.
Examples of the condensed polycyclic aromatic hydrocarbon group include groups having a skeleton such as indene, naphthalene, azulene, anthracene and phenanthrene.

As ^{the heteroaryl group having 4 to 12 carbon atoms of R 1} and R ² , at least one selected from oxygen atom, nitrogen atom and sulfur atom is used as a skeleton instead of at least one carbon atom of the aryl group. Included.

The heteroaryl group includes a monocyclic aromatic heterocyclic group, and a condensed polycyclic aromatic heterocycle in which at least one of the monocyclic aromatic heterocycles is condensed with the aromatic hydrocarbon group, the aliphatic heterocyclic group, or the like. Ring groups and the like can be mentioned. These aromatic heterocyclic groups may have a substituent.
Examples of the monocyclic aromatic heterocyclic group include groups having a skeleton such as furan, thiophene, thiazole, pyrrole, imidazole, pyridine, pyrimidine and pyrazine.

Examples of the condensed polycyclic aromatic heterocyclic group include groups having a skeleton such as indole, purine, quinoline, isoquinoline, chromene, phenoxazine, xanthene, acridine, phenazine and carbazole.

Examples of the ^{substituent (hereinafter, also referred to as “first substituent”) that R 1} and R ² may have include a hydroxy group, a cyano group, a mercapto group, a carboxy group, an alkoxy group (-OR ⁷ ), and an alkylsulfanyl. group (-CSR ^7), alkylcarbonyl group (-COR ^7), an alkoxycarbonyl group (-COOR ^7), an aryl group (-Ar ^1), an aryloxy group (-OAr ^1), arylsulfanyl group (-CSAr ¹⁾ , Amino group, alkylamino group (-NHR ⁷ ), dialkylamino group (-N (R ⁷ ) ₂ ), arylamino group (-NHAr ¹ ), diarylamino group (-N (Ar ¹ ) ₂ ), N- Alkyl-N-arylamino group (-NR ⁷ Ar ¹ ) phosphino group, silyl group, halogen atom, trialkylsilyl group (-Si- (R ⁷ ) ₃ ), at least one of the alkyl groups of the trialkylsilyl group Examples thereof include, but are not limited to, a silyl group substituted with Ar ^{1 , an alkylsulfanyl group (-SR 7} ), an arylsulfanyl group (-SAR ¹ ), and the like.
Among these, it is preferable to have a polar group such as a hydroxy group, a mercapto group, an alkylsulfanyl group, an arylsulfanyl group and a cyano group as the first substituent because the lithography characteristics are improved.
Further, it may have a polymerizable group such as a (meth) acryloyl group as the first substituent.

The above R ¹ and R ² form a ring structure together with the sulfur atom to which they are bonded, either directly in a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and a methylene group. May be good.

^{The R 7} in the first substituent is preferably an alkyl group having 1 or more carbon atoms. The alkyl group having 1 or more carbon atoms can be selected from the same options as the alkyl groups as ^{R 1} and R ^{2 described above.} Further, ^one of the hydrogens of the alkyl group as R 1 is a silyl group substituted alkyl group substituted with a trialkylsilyl group such as a trimethylsilyl group, a triethylsilyl group or a dimethylethylsilyl group; at least one of these hydrogen atoms is Alkyl groups substituted with a cyano group, a fluoro group or the like; and the like are also preferably mentioned.

^{Ar 1} in the first substituent is preferably an aryl group or a heteroaryl group. Ar ¹ can be selected from the same options as the aryl group and heteroaryl group as ^{R 1} and R ² described above.
The sulfonium salt in one embodiment of the present invention may be a polymer component bonded to a part of the polymer, or may be a polymer component contained as a polymer unit.
In the present invention, the low molecular weight compound has a weight average molecular weight of less than 2000, and the polymer component has a weight average molecular weight of 2000 or more.

As R ¹ and R ² , aryl groups are preferable from the viewpoint of high absorption in the i-line region and improvement of stability.

The alkyl group and alkenyl group in R ³ can be selected from the same options as the alkyl group and alkenyl group as ^{R 1} and R ^{2, respectively.}
The alkoxy group, aryloxy group, alkylsulfanyl group and arylsulfanyl group in R ³ can be selected from the same options as the alkoxy group of the first substituent, the aryloxy group, the alkylsulfanyl group and the arylsulfanyl group, respectively.
Examples of the alkylsulfonyl group and the arylsulfonyl group in R ³ include those in which the sulfonyl group has an alkyl group or an aryl group as the first substituent.
R ³ may have a substituent (hereinafter, also referred to as “second substituent”). The second substituent can be selected from the same options as the first substituent.

R ³ is preferably an alkyloxy group or an aryloxy group from the viewpoint of improving the molar extinction coefficient at 365 nm by shifting absorption.

The alkyl group, alkenyl group, aryl group and heteroaryl group as R ⁴ and R ⁵ can be selected from the same options as the alkyl group, alkenyl group, aryl group and heteroaryl group as ^{R 1} and R ^{2, respectively.}
Examples of the alkylcarbonyloxy group, alkenylcarbonyloxy group, arylcarbonyloxy group and heteroarylcarbonyloxy group as R ⁴ and R ⁵ include those in which the carbonyloxy group has an alkyl group or an aryl group as the first substituent. ..
R ⁴ and R ⁵ may have a substituent (hereinafter, also referred to as “third substituent”). Examples of the third substituent include those similar to the first substituent.

As R ⁴ and R ⁵ , alkyl, alkenyl or aralkyl groups are preferable from the viewpoint of increasing the molar extinction coefficient at 365 nm.

Examples of the halogen atom of R ⁶ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
Alkyl group, an alkenyl group of R ^6, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, an alkylsulfanyl group, an arylsulfanyl group, an alkylsulfonyl group; arylsulfonyl groups, heteroarylsulfonyl groups, alkylcarbonyloxy groups, alkenyl carbonyloxy group, an arylcarbonyloxy group and heteroarylcarbonyl group may be selected from the same options as R ⁴ and R ^5.

At least one methylene group in the above R ⁴ , R ⁵ and R ⁶ may be substituted with the above divalent heteroatom-containing group.
n is an integer from 0 to 4.
^{At least two of R 1 to} R ⁵ described above form a ring structure together with the sulfur atom to which they are bonded, either directly in a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and a methylene group. It may be formed.
At least two of the two or more R ⁶ is directly a single bond or an oxygen atom, may form a ring structure via one selected from the group consisting of a sulfur atom and a methylene group.

The sulfonium salt in one embodiment of the present invention may be a polymer component bonded to a part of the polymer, or may be a polymer component contained as a polymer unit. When it is a polymer component, the main chain of the polymer is mentioned as the second substituent ^{, and the number of carbon atoms of each of R 1 to} R ⁶ is adjusted so that the weight average molecular weight of the entire polymer is 2000 to 200,000. Is preferable.

In some aspects of the present invention, examples of the sulfonium onium cation include those shown below, but the present invention is not limited thereto.

The above X ⁻ is a monovalent counter anion.

The anion is not particularly limited, and examples thereof include anions such as sulfonic acid anion, carboxylate anion, imide anion, methide anion, carbo anion, borate anion, halogen anion, phosphate anion, antimonate anion, and arsenic anion.
More specifically, as an _{^{anion, ZA a-, (Rf) b}} PF (6-b) -, R 10 c BA (4-c) -, R 10 c GaA (4-c) -, R 11 SO 3 - , (R ¹¹ SO ₂ ) ₃ C ⁻ or (R ¹¹ SO ₂ ) ₂ N ⁻ anions are preferred. Two of Rf and two of R ¹⁰ and R ¹¹ may be combined with each other to form a ring.

Z represents a phosphorus atom, a boron atom or an antimony atom. A represents a halogen atom (preferably a fluorine atom).
P represents a phosphorus atom, F represents a fluorine atom, B represents a boron atom, and Ga represents a gallium atom.
S represents a sulfur atom, O represents an oxygen atom, C represents a carbon atom, and N represents a nitrogen atom.

Rf is preferably an alkyl group in which 80 mol% or more of hydrogen atoms are substituted with a fluorine atom, and the alkyl group is preferably an alkyl group having 1 to 8 carbon atoms. Alkyl groups to be Rf by fluorine substitution include linear alkyl groups (methyl, ethyl, propyl, butyl, pentyl, octyl, etc.), branched alkyl groups (isopropyl, isobutyl, s-butyl, t-butyl, etc.) and Cycloalkyl groups (cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, etc.) and the like can be mentioned. The ratio of hydrogen atoms of these alkyl groups substituted with fluorine atoms in Rf is preferably 80 mol% or more, more preferably 90, based on the number of moles of hydrogen atoms possessed by the original alkyl group. % Or more, particularly preferably 100%.
When the substitution ratio by the fluorine atom is in these preferable ranges, the photosensitivity of the sulfonium salt is further improved. Particularly preferred Rf are CF ₃ ⁻ , CF ₃ CF ₂ ⁻ , (CF ₃ ) ₂ CF ⁻ , CF ₃ CF ₂ CF ₂ ⁻ , CF ₃ CF ₂ CF ₂ CF ₂ ⁻ , (CF ₃ ) ₂ CFCF ₂ ^−. , CF ₃ CF ₂ (CF ₃ ) CF ⁻ and (CF ₃ ) ₃ C ⁻ . The b Rfs are independent of each other and therefore may be the same or different from each other.

R ¹⁰ represents a phenyl group in which a part of a hydrogen atom is substituted with at least one halogen atom or an electron-withdrawing group. Examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom. Examples of the electron attracting group include a trifluoromethyl group, a nitro group and a cyano group. Of these, a phenyl group in which one hydrogen atom is replaced with a fluorine atom or a trifluoromethyl group is preferable. The c R ^10s are independent of each other and therefore may be the same or different from each other.

R ¹¹ represents an alkyl group having 1 to 20 carbon atoms, a perfluoroalkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the perfluoroalkyl group are linear or branched. It may be chain-like or cyclic, and the aryl group may be unsubstituted or have a substituent.

a represents an integer of 4 to 6. b represents an integer of 1 to 5, preferably 2 to 4, particularly preferably 2 or 3. c represents an integer of 1 to 4, preferably 4.

Examples of the _{anion represented by ZA a} ⁻ include anions represented by SbF ₆ ⁻ , PF ₆ ⁻ and BF ₄ ⁻ .

_{(Rf) b PF (6-} b) - as the anion represented by ^{_{the, (CF 3 CF 2) 2}} PF 4 -, (CF 3 CF 2) 3 PF 3 -, ((CF 3) 2 CF) 2 ^{_{PF 4 -, ((CF 3}} ) 2 CF) 3 PF 3 -, (CF 3 CF 2 CF 2) 2 PF 4 -, (CF 3 CF 2 CF 2) 3 PF 3 -, ((CF 3) 2 CFCF ^{_{2) 2 PF 4 -, (}} (CF 3) 2 CFCF 2) 3 PF 3 -, (CF 3 CF 2 CF 2 CF 2) 2 PF 4 - , and _{(CF 3 CF 2 CF 2 CF} 2) 3 PF 3 - Examples thereof include anions represented by. Of ^{_{these, (CF 3 CF 2) 3}} PF 3 -, (CF 3 CF 2 CF 2) 3 PF 3 -, ((CF 3) 2 CF) 3 PF 3 -, ((CF 3) 2 CF) 2 ^{_{PF 4 -, ((CF 3}} ) 2 CFCF 2) 3 PF 3 - , and _{((CF 3) 2 CFCF 2} )
₂ PF ₄ ^- anion represented by are preferred.

The anions represented by ^{R 10} _c BA _(4-c) ⁻ _{include (C 6} F ₅ ) ₄ B ⁻ , ((CF ₃ ) ₂ C ₆ H ₃ ) ₄ B ⁻ , (CF ₃ C ₆ H _{4). ^{) 4 B -, (C 6}} F 5) 2 BF 2 -, C 6 F 5 BF 3 - and _{(C 6 H 3 F 2)} 4 B - anion, and the like represented. Of these, anions represented by _{(C 6} F ₅ ) ₄ B ⁻ and ((CF ₃ ) ₂ C ₆ H ₃ ) ₄ B ^{− are preferred.}

The anions represented by ^{R 10} _c GaA _(4-c) ⁻ _{include (C 6} F ₅ ) ₄ Ga ⁻ , ((CF ₃ ) ₂ C ₆ H ₃ ) ₄ Ga ⁻ , (CF ₃ C ₆ H _4). ) ₄ Ga ⁻ , (C ₆ F ₅ ) _{2 Ga F 2} ⁻ , C ₆ F ₅ Ga F ₃ ⁻ and (C ₆ H _{3 F 2} ) ₄ ^{Ga −} , and the like. Of these, anions represented by _{(C 6} F ₅ ) ₄ Ga ⁻ and ((CF ₃ ) ₂ C ₆ H ₃ ) ₄ Ga ^{− are preferable.}

Examples of the anion represented by R ¹¹ SO ₃ ⁻ include those described in WO2011 / 093139. Specifically, as the radiation-sensitive acid generator, a sulfonic acid derivative having an anionic structure represented by the following formula (a1) is preferable, but the agent is not limited thereto.

^{_{R 11a COOCH 2 CH 2 CFHCF 2}} SO 3 - (a1)
In the above formula (a1), R ^11a represents a monovalent organic group having 1 to 20 carbon atoms which may have a substituent. The organic group preferably includes a group represented by the following formula having 1 to 20 carbon atoms.
R ^11b- (L-R ^11c ) _m- (a2)

In the above formula (a2), R ^11b is a linear, branched or cyclic monovalent aliphatic hydrocarbon group; a monovalent aromatic hydrocarbon group; and -O-, -CO-, -COO. -, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH-CO-O-, -O-CO-NH-, -NH-, -N =, -S-, Any monovalent group selected from a monovalent aliphatic heterocyclic group or a monovalent aromatic heterocyclic group containing at least one group in the skeleton selected from the group consisting of −SO − and −SO _{2 −.} It is a group.
In addition, L is directly bound to each other independently; or -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH-CO-. It is any group selected from the group consisting of O-, -O-CO-NH-, -NH-, -S- and -CO-O-CH _2-CO-O-.
Each of R ^11c independently has a linear, branched or cyclic divalent aliphatic hydrocarbon group; a divalent aromatic hydrocarbon group; and -O-, -CO-, -COO-,-. OCO-, -O-CO-O
From the group consisting of-, -NHCO-, -CONH-, -NH-CO-O-, -O-CO-NH-, -NH-, -N =, -S-, -SO- and -SO _2- A divalent aliphatic heterocyclic group or a divalent aromatic heterocyclic group containing at least one selected group in the skeleton; any of the divalent groups selected from the above.

Further, in the above formula (a2), m is 0 or an integer of 1 to 10. However, when m is 0, R ^11a has the hydroxyl group, and when m is 1 or more, ^{at least one of R 11b} and R ^11c has the hydroxyl group. m is preferably 0 to 5, more preferably 0 to 3.
When R ^11a has a substituent, the number of carbon atoms is preferably 1 to 200, more preferably 1 to 100, including the number of carbon atoms of the substituent. The number of carbon atoms is more preferably 1 to 30, and the number of carbon atoms is particularly preferably 3 to 30. Further, ^{it is preferable that R 11a} has a substituent, that is, ^{at least one hydrogen of R 11b} and R ^11c is substituted with the substituent.
Examples of the substituent that R ^11a may have include a hydroxy group, a carboxyl group, an alkoxy group, an acyl group, an alkoxycarbonyl group, an aryl group, an aryloxy group, a phosphino group, an alkylthio group and an arylthio group. Yes, but not limited to these.
R ¹¹ SO ₃ ^- as the anion represented by, in addition to anions represented by the above formula (a1), trifluoromethanesulfonic acid anion, pentafluoroethanesulfonate anion, heptafluoropropanesulfonate acid anion, nonafluorobutanesulfonic acid anion , Pentafluorophenyl sulfonic acid anion, p-toluene sulfonic acid anion, benzene sulfonic acid anion, camphor sulfonic acid anion, methane sulfonic acid anion, ethane sulfonic acid anion, propane sulfonic acid anion, butane sulfonic acid anion and the like. Among these, trifluoromethanesulfonic acid anion, nonafluorobutanesulfonic acid anion, methanesulfonic acid anion, butanesulfonic acid anion, benzenesulfonic acid anion, p-toluenesulfonic acid anion and the like can be mentioned.

The anions represented by (R ¹¹ SO ₂ ) ₃ C ⁻ _{are (CF 3} SO ₂ ) ₃ C ⁻ , (C ₂ F ₅ SO ₂ ) ₃ C ⁻ , and (C ₃ F ₇ SO ₂ ) ₃ C ^−. and _{(C 4 F 9 SO 2)} 3 C - anion such as represented and the like.

The anions represented by (R ¹¹ SO ₂ ) ₂ N ⁻ _{are (CF 3} SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , and (C ₃ F ₇ SO ₂ ) ₂ N ^−. And (C ₄ F ₉ SO ₂ ) ₂ N ⁻ anions and the like can be mentioned. In addition, _{a cyclic imide in which the portions corresponding to the two} ^{(R 11} SO 2) are bonded to each other to form a ring structure is also mentioned as an anion represented by ^{(R 11} SO ₂ ) ₂ N ^−.

The monovalent anion, in addition to the above anions, perhalogenated acid ion _{^(ClO 4} ^-, BrO 4 -, etc.), halogenated sulfonic acid ion _{^(FSO 3} ^-, ClSO 3 -, etc.), sulfate ion _(CH 3 SO _{4 ^{-, CF 3 SO 4 -,}} HSO 4 - , etc.), carbonate ions _{^{(HCO 3 -, CH 3 CO}} 3 - , etc.), aluminate ions (AlCl ₄ ^-, AlF ₄ ^-, etc.), hexafluorodisiloxane mass ion (BiF ₆ ^-), carboxylate ion _{^{(CH 3 COO -, CF 3}} COO -, C 6 H 5 COO -, CH 3 C 6 H 4 COO -, C 6 F 5 COO -, CF 3 C 6 H 4 COO - , etc. ), Arylborate ion (B (C ₆ H ₅ ) ₄ ⁻ , CH ₃ CH ₂ CH ₂ CH ₂ B (C ₆ H ₅ ) ₃ ^−, etc.), Thiosyanate ion (SCN ⁻ ) and Nitrate ion (NO ₃ ^−). ) Etc. can be used.

Of these anions, sulfonic acid anions and the like are preferable.

<2> Method for producing the above-mentioned sulfonium salt A method for synthesizing a sulfonium salt in one embodiment of the present invention will be described. The present invention is not limited to this.
Examples of the method for synthesizing the sulfonium salt of interest include the methods shown below as described in Chemistry --A European Journal, 14 (21), 6490-6497, 2008. Hereinafter, the synthesis method represented by the above formula (1) will be illustrated, but the present invention is not limited thereto.
First, thiosalicylic acid (which may have a ^{substituent R 6} if necessary) and bromobenzene having a substituent of ^{R 3 (which may have an R 4} and / or R ⁵ substituent if necessary). Cu, KI and K ₂ CO ₃ are mixed and reacted for 10 hours to obtain a 2-phenylsulfanyl benzoic acid derivative (formula (3) below). Next, it is converted to an acid chloride by thionyl chloride treatment and then cyclized in the presence of a Lewis acid catalyst to form a thioxanthone derivative (hereinafter, the compound represented by the following formula (4) before the introduction of the sulfonium group is referred to as "thioxanthone derivative"). To get. The thioxanthone derivative ^{is mixed with sulfoxide having R 1} and R ² substituents, methanesulfonic acid and diphosphorus pentoxide and reacted to obtain a sulfonium salt having a thioxanthone skeleton (formula (1) below).
Examples of R ^{1 to} R ⁶ and n are the same as described above.

In the above reaction, monovalent or divalent Cu can be used instead of zero-valent copper, and an acid anhydride or carboxylic acid is used instead of the acid chloride in the cyclization reaction, and Bronsted acid is used instead of Lewis acid. Can also be used.

In the synthesis of the sulfonium salt, when introducing sulfonium group to thioxanthone derivatives, it is preferable to have a specific substituent R ³ in the 3-position of the thioxanthone derivatives in view of the reaction selectivity and suppressing the formation of the dication of thioxanthone derivatives. Further, more preferably the substituents R ⁵ of the thioxanthone derivative (the formula (4)) is a substituent R ³ is different substituents, and more preferably the substituent R ⁵ is a hydrogen atom. By doing so, the reaction selectivity is improved, dications are less likely to be generated, and monocations can be efficiently obtained.
When a sulfonium group is introduced into the thioxanthone derivative, dications are less likely to be generated in the obtained sulfonium salt. Therefore, ^{as R 3} of the thioxanthone derivative, an alkyloxy group, an aryloxy group or the like is preferable.

The introduction of the sulfonium group into the thioxanthone derivative may result in a mixture of 2- and 4-positions. In one embodiment of the present invention, the 2-position and 4-position may be isolated and used, respectively, but they can also be used as a mixture. The ratio of the 2-position to the 4-position when used as a mixture is not particularly limited, but a large amount of 2-position is preferable from the viewpoint of acid generation efficiency. Specifically, the ratio of the 2-position body to the 4-position body is preferably 7: 3 to 5: 5.

<3> Photoacid generator Some aspects of the present invention are photoacid generators containing the sulfonium salt.

As mentioned above, the sulfonium salt in some aspects of the invention may be a polymeric component. At that time, it is also a preferable embodiment to use a sulfonium salt having an unsaturated bond other than the aryl group in the molecule as a monomer constituting the polymer unit. When used as a monomer constituting a unit of a polymer, the polymer may be a homopolymer or a copolymer having other units. Examples of other units when they are copolymers include those that act as acid-reactive compounds and hydroxyaryl group-containing units. Those that act as the acid-reactive compound, hydroxyaryl group-containing units, and the like will be described later.

<4> Composition One aspect of the present invention relates to a composition containing the above-mentioned photoacid generator and an acid-reactive compound.
(Photoacid generator)
The content of the photoacid generator in the composition of one aspect of the present invention is preferably 0.1 to 50 parts by mass with respect to 100 parts by mass of the resist composition component excluding the photoacid generator. It is more preferably 1 to 30 parts by mass, and even more preferably 3 to 15 parts by mass.
In calculating the content of the photoacid generator, the organic solvent is not contained in 100 parts by mass of the resist composition component.
When the photoacid generator is a polymer, it is based on the mass excluding the polymer main chain. When the photoacid generator is contained as a unit of the same polymer together with at least one selected from the group consisting of a hydroxyaryl group-containing unit and an acid-reactive compound described later, a unit that acts as the photoacid generator. Is preferably 0.1 to 40 mol%, more preferably 1 to 30 mol%, and even more preferably 3 to 20 mol% of the total polymer unit.

(Acid-reactive compound)
The acid-reactive compound is at least one selected from the group consisting of a compound having a protecting group that is deprotected by an acid, a compound having a polymerizable group that polymerizes by an acid, and a cross-linking agent having a cross-linking action by an acid. It is preferable to have.

A compound having a protecting group that is deprotected by an acid is a compound that produces a polar group by deprotecting the protecting group by an acid and changes its solubility in a developing solution. For example, in the case of water-based development using an alkaline developer or the like, the protective group is deprotected from the compound in the exposed portion by the acid generated from the photoacid generator by exposure, although it is insoluble in the alkaline developer. , A compound that is soluble in alkaline developers.

In the present invention, the developer is not limited to the alkaline developer, and may be an aqueous neutral developer or an organic solvent developer. Therefore, when an organic solvent developing solution is used, a compound having a protecting group that is deprotected by an acid is polar because the protecting group is deprotected from the compound in an exposed portion by an acid generated from the photoacid generator by exposure. It is a compound that produces a group and has reduced solubility in an organic solvent developing solution.
Examples of the polar group include a hydroxy group, a carboxy group, an amino group and a sulfo group. Among these, a polar group having −OH in the structure is preferable, and a hydroxy group or a carboxy group is preferable.

Specific examples of the protecting group to be deprotected with an acid include a group forming a carboxy group and a tertiary alkyl ester group; an alkoxyacetal group; a tetrahydropyranyl group; a syroxy group and a benzyloxy group. As the compound having the protecting group, a compound having a styrene skeleton, a methacrylate or an acrylate skeleton in which these protecting groups are pendant, and the like are preferably used.

The compound having a protecting group to be deprotected by an acid may be a low molecular weight compound containing a protecting group or a unit-containing polymer component having a protecting group.

A compound having a polymerizable group that polymerizes with an acid is a compound that changes its solubility in a developing solution by polymerizing with an acid. For example, in the case of aqueous development, it acts on a compound that is soluble in an aqueous developer, and after polymerization, the compound is reduced in solubility in an aqueous developer. Specific examples thereof include compounds having an epoxy group, a vinyloxy group, an oxetanyl group and the like.
The compound having a polymerizable group polymerized by an acid may be a polymerizable low molecular weight compound or a unit-containing polymer component having a polymerizable group.

A cross-linking agent having a cross-linking action with an acid is a compound that changes its solubility in a developing solution by cross-linking with an acid. For example, in the case of aqueous development, it acts on a compound that is soluble in an aqueous developer, and reduces the solubility of the compound in an aqueous developer after polymerization or cross-linking. Specific examples thereof include a cross-linking agent having a cross-linking group such as an epoxy group, a vinyloxy group, a 1-alkoxyamino group and an oxetanyl group. When the compound is a cross-linking agent having a cross-linking action, examples of the compound to be cross-linked, that is, the compound whose solubility in the developing solution changes by reacting with the cross-linking agent includes a compound having a phenolic hydroxyl group.
The compound having a cross-linking action by an acid may be a cross-linking low molecular weight compound or a unit-containing polymer component having a cross-linking group.

When the acid-reactive compound is a polymer component, in addition to the unit containing the deprotecting group, other units usually used in the resist composition may be contained in the polymer component. Other units include, for example, a unit having at least one of the skeletons selected from the group consisting of a lactone skeleton, a sulton skeleton, a lactam skeleton, etc .; A unit having at least one of the groups selected from the group consisting of; a hydroxyaryl group-containing unit; and the like can be mentioned. Further, the photoacid generator may be contained as a unit.
When the acid-reactive compound is contained as a unit of the same polymer together with at least one selected from the group consisting of the photoacid generator and the hydroxyaryl group-containing unit described later, the unit acting as the acid-reactive compound is , 3 to 40 mol%, more preferably 5 to 35 mol%, still more preferably 7 to 30 mol% of the total polymer unit.

(Polymer having a hydroxyaryl group-containing unit)
In one aspect of the invention, it is preferred that the composition further comprises a polymer having a hydroxyaryl group-containing unit. The hydroxyaryl group-containing unit may be contained in a polymer containing the acid generator and / or an acid-reactive compound as a unit, or may be a unit of another polymer.

When a polymer having a hydroxyaryl group-containing unit is used, it can be a hydrogen source when the photoacid generator is decomposed, the acid generation efficiency is further improved, and the sensitivity becomes high, which is preferable.
The hydroxyaryl group-containing unit preferably includes, but is not limited to, the unit represented by the following formula. The benzene skeleton of the hydroxyaryl group-containing unit may have a substituent other than the hydroxy group. Examples of the substituent other than the hydroxy group include an alkyl group and an aryl group.

When the hydroxyaryl group-containing unit is included as a unit of the same polymer together with at least one selected from the group consisting of the photoacid generator and the acid-reactive compound, the hydroxyaryl group-containing unit is subjected to aqueous development. For positive resist compositions, it is preferably 3 to 90 mol%, more preferably 5 to 80 mol%, and even more preferably 7 to 70 mol% of the total polymer unit. For water-based developed negative resist compositions, it is preferably 60 to 99 mol%, more preferably 70 to 98 mol%, and even more preferably 75 to 98 mol% of the total polymer unit.

(Fluorine-containing water-repellent polymer)
The composition of one embodiment of the present invention may contain a fluorine-containing water-repellent polymer.
The fluorine-containing water-repellent polymer is not particularly limited, and examples thereof are those usually used in an immersion exposure process, and a polymer having a higher fluorine atom content than the polymer is preferable. Thereby, when the resist film is formed by using the composition, the fluorine-containing water-repellent polymer can be unevenly distributed on the surface of the resist film due to the water repellency of the fluorine-containing water-repellent polymer.

As for the fluorine content of the fluorine-repellent polymer, it is preferable that 25 mol% or more of hydrogen atoms in the hydrocarbon group in the fluorine-repellent polymer is fluorinated, and 50 mol% or more is fluorinated. Is more preferable.

The content of the fluorine-repellent polymer in the composition shall be 0.5 to 10 parts by mass with respect to 100 parts by mass of the above-mentioned polymer (non-fluorine-repellent polymer) of one aspect of the present invention. However, it is preferable from the viewpoint of improving the hydrophobicity of the resist film. The fluorine-repellent polymer may be used alone or in combination of two or more.

(Other ingredients)
In the composition of one aspect of the present invention, an acid diffusion control agent, a surfactant, an organic carboxylic acid, an organic solvent, and a dissolution inhibitor used in ordinary resist compositions are further added as optional components in addition to the above components. , Stabilizers and dyes, sensitizers, polymers other than the above, and other photoacid generators may be contained in combination.

The acid diffusion control agent has the effect of controlling the diffusion phenomenon of the acid generated from the photoacid generator in the resist film and controlling an unfavorable chemical reaction in the non-exposed region. Therefore, the storage stability of the obtained resist composition is further improved, the resolution of the resist is further improved, and the line width change of the resist pattern due to the fluctuation of the leaving time from the exposure to the development process can be suppressed. , A resist composition having excellent process stability can be obtained.
Examples of the acid diffusion control agent include a compound having one nitrogen atom in the same molecule, a compound having two nitrogen atoms, a compound having three nitrogen atoms, an amide group-containing compound, a urea compound, and a nitrogen-containing heterocyclic compound. Be done. Further, as the acid diffusion control agent, a photodisintegrating base that is exposed to light and generates a weak acid by exposure can also be used. Examples of the photodisintegrating base include onium salt compounds and iodonium salt compounds that are decomposed by exposure and lose their acid diffusion controllability.
Specifically, Japanese Patent Application Laid-Open No. 3577743, Japanese Patent Application Laid-Open No. 2001-215689, Japanese Patent Application Laid-Open No. 2001-166476, Japanese Patent Application Laid-Open No. 2008-102383, Japanese Patent Application Laid-Open No. 2010-243773, Japanese Patent Application Laid-Open No. 2011-378535 and Japanese Patent Application Laid-Open No. 2012-173505. Examples of the compounds described in.
The content of the acid diffusion control agent is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5% by mass, and 0.05 to 0.05 to 100 parts by mass with respect to 100 parts by mass of the resist composition component. It is more preferably 3% by mass.

The above-mentioned surfactant is preferably used to improve the coatability. Examples of surfactants include nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene polyoxypropylene block copolymers, sorbitan fatty acid esters, and polyoxyethylene sorbitan fatty acid esters. Examples thereof include agents, fluorosurfactants, and organosiloxane polymers.
The content of the surfactant is preferably 0.0001 to 2 parts by mass, more preferably 0.0005 to 1% by mass, based on 100 parts by mass of the resist composition component.

Examples of the organic carboxylic acid include aliphatic carboxylic acid, alicyclic carboxylic acid, unsaturated aliphatic carboxylic acid, oxycarboxylic acid, alkoxycarboxylic acid, ketocarboxylic acid, benzoic acid derivative, phthalic acid, terephthalic acid, isophthalic acid, 2 Examples thereof include −naphthoic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid and the like. When electron beam exposure is performed by vacuuming, it may volatilize from the surface of the resist film and contaminate the inside of the drawing chamber. Therefore, preferable organic carboxylic acids are aromatic organic carboxylic acids, among which, for example, benzoic acid. 1-Hydroxy-2-naphthoic acid and 2-hydroxy-3-naphthoic acid are suitable.
The content of the organic carboxylic acid is preferably 0.01 to 10 parts by mass, more preferably 0.01 to 5 parts by mass, and even more preferably 0.01 to 3 parts by mass with respect to 100 parts by mass of the resist composition component. Is.

Examples of the organic solvent include ethylene glycol monoethyl ether acetate, cyclohexanone, 2-heptanone, propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether propionate, and propylene glycol monoethyl ether. Acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl β-methoxyisobutyrate, ethyl butyrate, propyl butyrate, methylisobutylketone, ethyl acetate, isoamyl acetate, ethyl lactate, toluene, xylene, cyclohexyl acetate, diacetone Alcohol, N-methylpyrrolidone, N, N-dimethylformamide, γ-butyrolactone, N, N-dimethylacetamide, propylene carbonate, ethylene carbonate and the like are preferable. These organic solvents are used alone or in combination.
The resist composition component is preferably dissolved in the above-mentioned container solvent and dissolved in a solid content concentration of 1 to 40% by mass. It is more preferably 1 to 30% by mass, still more preferably 3 to 20% by mass. The above film thickness can be achieved by setting the solid content concentration in such a range.

When the resist composition of one embodiment of the present invention comprises a polymer, the polymer preferably has a weight average molecular weight of 2000 to 200,000, more preferably 2000 to 50000, and even more preferably 2000 to 15000. preferable. The preferred dispersity (molecular weight distribution) (Mw / Mn) of the polymer is 1.0 to 1.7, more preferably 1.0 to 1.2, from the viewpoint of sensitivity. The weight average molecular weight and dispersity of the polymer are defined as polystyrene-equivalent values measured by GPC.

The composition of one aspect of the present invention is obtained by mixing each component of the above composition, and the mixing method is not particularly limited.

<5> Device Manufacturing Method One aspect of the present invention is a resist film forming step of forming a resist film by applying the resist composition onto a substrate, and exposing the resist film using active energy rays. This is a method for manufacturing a device, which includes a photolithography step of developing a resist film and a pattern forming step of developing an exposed resist film to obtain a photoresist pattern.

By using the photoresist pattern as a thick film and embedding a conductor such as metal in the non-resist portion of the thick film photoresist pattern, for example, by plating or the like, connection terminals such as metal posts and bumps can be formed. The plating treatment method is not particularly limited, and various known methods can be used.

One embodiment of the present invention is a method for producing a substrate having a pattern before obtaining an individualized chip, which comprises a resist film forming step, a photolithography step, and a pattern forming step using the resist composition. May be good.
One embodiment of the present invention includes a coating film forming step of forming a coating film on a substrate using the above photocurable composition.
It may be a method of manufacturing a device including the step of exposing the coating film with an active energy ray to obtain an interlayer insulating film.

The active energy rays used for exposure in the photolithography step may be any light that can activate the sulfonic acid derivative of the present invention to generate acid, such as KrF excimer laser light, ArF excimer laser light, and F ₂ excimer laser light. It means electron beam, UV, visible light, X-ray, electron beam, ion beam, i-ray, EUV and the like.

The substrate is not particularly limited and a known substrate can be used. For example, a metal substrate such as silicon, silicon nitride, titanium, tantalum, palladium, copper, chromium, aluminum; a glass substrate; and the like can be mentioned. In particular, when the sulfonium salt in one embodiment of the present invention has a hydroxy group, a mercapto group, an alkylsulfanyl group, an arylsulfanyl group or a cyano group in the structure, and a composition containing the sulfonium salt is used as a resist composition. Since the sulfonium salt in one aspect of the present invention can be unevenly distributed on the surface of a metal substrate such as copper, a resist pattern can be satisfactorily formed.
In one aspect of the present invention, i-ray is preferably mentioned as the active energy ray used for exposure in the photolithography step or the step of obtaining the interlayer insulating film.

The amount of light irradiation varies depending on the type and blending ratio of each component in the photocurable composition, the film thickness of the coating film, and the like, but ^{is preferably 1 J / cm 2} or less or 1000 μC / cm ² or less.

In one aspect of the present invention, the film thickness of the resist film formed by the resist composition is preferably 10 to 200 nm. The resist composition is applied onto a substrate by an appropriate coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, etc., and is applied at 60 to 150 ° C. for 1 to 20 minutes, preferably 80 to 80 to. Prebake at 120 ° C. for 1-10 minutes to form a thin film. The film thickness of this coating film is 10 to 200 nm, preferably 20 to 150 nm.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

<Synthesis of sulfonium salt 1>
(Synthesis Example 1) Synthesis of 2- (3-methoxyphenyl sulfanyl) benzoic acid With 6.7 g of thiosalicylic acid, 8.1 g of 3-bromoanisole, 0.8 g of copper, 6.0 g of potassium carbonate, N, and N-dimethylformamide. Are mixed and stirred at 140 ° C. for 20 hours. After cooling to 25 ° C., crystallization is performed by adding water. After the crystals are filtered off, they are dissolved in acetone, crystallized by adding water again, and the crystals are filtered off to obtain 7.4 g of 2- (3-methoxyphenyl sulfanyl) benzoic acid.

(Synthesis Example 2) Synthesis of 2- (3-methoxyphenyl sulfanyl) benzoyl chloride 5.0 g of 2- (3-methoxyphenyl sulfanyl) benzoic acid obtained in Synthesis Example 1 was added to 25 g of toluene to add thionyl chloride 4 .3 g is added dropwise and reacted at 25 ° C. for 6 hours. After the reaction, the solvent is distilled off to obtain 5.1 g of the target 2- (3-methoxyphenyl sulfanyl) benzoyl chloride.

(Synthesis Example 3) Synthesis of 3-methoxythioxanthene-9-one Add 2.5 g of aluminum chloride to 30 g of methylene chloride to bring the temperature to 0 ° C. 2- (3-Methoxyphenylsulfanyl obtained in Synthesis Example 2). ) 5.0 g of benzoyl chloride is diluted with 10 g of methylene chloride and added dropwise. After the dropping, the mixture is stirred at 25 ° C. for 1 hour. After stirring, the temperature is adjusted to 0 ° C., 20 g of pure water is added to stop the reaction, the reaction is stopped twice at 25 ° C. with 10 g of a 5% sodium carbonate aqueous solution, washed twice with 20 g of pure water, and then methylene chloride is distilled off. The obtained solid is recrystallized from ethanol to obtain 3.5 g of 3-methoxythioxanthene-9-one.

(Synthesis Example 4) (3-Methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium Nonafluorobutane sulfonate and (3-methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium Synthesis of a mixture of nonafluorobutane sulfonate (sulfonium salt 1) 5.0 g of 3-methoxythioxanthene-9-one obtained in Synthesis Example 3, 2.8 g of diphenyl sulfoxide, and 1.0 g of phosphorus pentoxide are added to 18 g of methanesulfonic acid. Dissolve in and stir at 40 ° C. for 3 hours. After stirring, 25 g of pure water is added and the mixture is further stirred for 10 minutes. 4.5 g of potassium nonaflatebutanesulfonate and 30 g of methylene chloride are added and the mixture is stirred for 1 hour. This is separated and washed with 20 g of pure water three times, and then methylene chloride is distilled off to obtain an oil containing 11% (HPLC Area%) of dication impurities. This is purified by silica gel column chromatography (methylene chloride / methanoln = 90/10 (volume ratio)) to (3-methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium nonaflate butane sulfonate. And (3-methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium nonaflate butane sulfonate mixture (sulfonium salt 1) is obtained in 7.2 g.
The obtained sulfonium salt 1 is 4-position: 2-position = 6: 4.

<Synthesis of sulfonium salt 2>
(Synthetic Example 5) (3-Methylsulfanyl-9-oxo-9H-thioxanthene-2-yl) Diphenylsulfonium nonafluorobutanesulfonate and (3-methylsulfanyl-9-oxo-9H-thioxanthene-2-yl) Synthesis of a mixture of diphenylsulfonium nonafluorobutane sulfonate (sulfonium salt 2) Synthesis was carried out in the same manner as in Synthesis Example 4 above, except that 3-methylsulfanylthioxanthene-9-one was used instead of 3-methoxythioxanthene-9-one. By purifying the oil containing 14% of dication impurities by column chromatography (3-methylsulfanyl-9-oxo-9H-thioxanthene-2-yl), diphenylsulfonium nonafluorobutane sulfonate and (3-methylsulfanyl-). A mixture of 9-oxo-9H-thioxanthene-2-yl) diphenylsulfonium nonafluorobutane sulfonate (sulfonium salt 2) is obtained. 3-Methylsulfanylthioxanthene-9-one can be synthesized according to Synthesis Examples 1 to 3. Further, the obtained sulfonium salt 2 is 4-position: 2-position = 6: 4.

<Synthesis of sulfonium salt 3>
(Synthetic Example 6) (1-Hydroxy-3-methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium nonafluorobutane sulfonate and (1-hydroxy-3-methoxy-9-oxo-9H-thio) Synthesis of a mixture of xanthene-2-yl) diphenylsulfonium nonafluorobutane sulfonate (sulfonium salt 3) Synthesis example except that 1,3-dimethoxythioxanthene-9-one is used instead of 3-methoxythioxanthene-9-one. Do the same as in step 4, and purify the oil containing 18% dication impurities (HPLC Area%) by column chromatography (1 hydroxy-3-methoxy-9-oxo-9H-thioxanthene-2-yl) diphenylsulfonium. A mixture of nonafluorobutane sulfonate and (1-hydroxy-3-methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium nonafluorobutane sulfonate (sulfonium salt 3) is obtained.
3-Dimethoxythioxanthene-9-one can be synthesized according to Synthesis Examples 1 to 3. Further, the obtained sulfonium salt 3 is 4-position: 2-position = 6: 4.

<Synthesis of sulfonium salt 4>
(Synthetic Example 7) (3-Methyl-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium Nonafluorobutane sulfonate and (3-methyl-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium Synthesis of Mixture of Nonafluorobutane Sulfonium (Sulfonium Salt 4) The procedure was the same as in Synthesis Example 4 except that 3-methylthioxanthene-9-one was used instead of 3-methoxythioxanthene-9-one, and 28% of dication impurities (sulphonium impurity 4). By purifying the oil containing (HPLC Area%) by column chromatography, (3-methyl-9-oxo-9H-thioxanthene-2-yl) diphenylsulfonium nonafluorobutane sulfonate and (1,3-dimethoxy-9-) A mixture of oxo-9H-thioxanthene-2-yl) diphenylsulfonium nonafluorobutane sulfonate (sulfonium salt 4) is obtained.
3-Methylthioxanthene-9-one can be synthesized according to Synthesis Examples 1 to 3. Further, the obtained sulfonium salt 4 is 4-position: 2-position = 6: 4.

<Synthesis of sulfonium salt 5>
(Synthetic Example 8) (3-Methylsulfonyl-9-oxo-9H-thioxanthen-2-yl) Diphenylsulfonium nonafluorobutane sulfonate and (3-methylsulfonyl-9-oxo-9H-thioxanthen-2-yl) Synthesis of Mixture of Diphenylsulfonium Nonafluorobutane Sulfonium (Sulfonium Salt 5) Diphenylsulfonium nonafluorobutane sulfonate and (3-methylsulfanium nonafluorobutane sulfonate) obtained in Synthesis Example 5 (3-methylsulfanyl-9-oxo-9H-thioxanthene-2-yl) Methylsulfanyl-9-oxo-9H-thioxanthene-2-yl) diphenylsulfonium Nonafluorobutane sulfonate mixture (sulfonium salt 2) 3 g and 35 mass% hydrogen peroxide solution 0.9 g dissolved in acetic acid 15 g at 40 ° C. Stir for 3 hours. After stirring, 30 g of pure water is added and the mixture is further stirred for 10 minutes, and 30 g of methylene chloride is added and the mixture is stirred for 10 minutes. This is separated and washed 3 times with 20 g of pure water, and then methylene chloride is distilled off, and this is purified by silica gel column chromatography (methylene chloride / methanoln = 90/10 (volume ratio)) (3-). Mixture of methylsulfonyl-9-oxo-9H-thioxanthene-2-yl) diphenylsulfonium nonafluorobutane sulfonate and (3-methylsulfonyl-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium nonaflate sulfonate (Sulfonium salt 5) is obtained.
The obtained sulfonium salt 5 is 4-position: 2-position = 6: 4.

<Synthesis of sulfonium salt 6>
(Synthetic Example 9) (1-acyloxy-3-methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium nonafluorobutane sulfonate and (1-acyloxy-3-methoxy-9-oxo-9H-thio) Synthesis of a mixture of diphenylsulfonium nonafluorobutane sulfonate (sulfonium salt 6) obtained in Synthesis Example 6 (1-hydroxy-3-methoxy-9-oxo-9H-thioxanthene-2-yl) diphenyl 3 g of a mixture of sulfonium nonafluorobutane sulfonate and a mixture of (1-hydroxy-3-methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium nonafluorobutane sulfonate (sulfonium salt 3) and 0.5 g of acetic anhydride Is dissolved in 15 g of methylene chloride, 0.5 g of triethylamine is added dropwise, and the mixture is stirred for 2 hours.
After stirring, 30 g of 1% hydrochloric acid water is added and the mixture is further stirred for 10 minutes, and 30 g of methylene chloride is added and the mixture is stirred for 10 minutes. This is separated and washed 3 times with 20 g of pure water, and then methylene chloride is distilled off, and this is purified by silica gel column chromatography (methylene chloride / methanoln = 90/10 (volume ratio)) (1-). Acyloxy-3-methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium Nonaflate sulfonate and (1-acyloxy-3-methoxy-9-oxo-9H-thioxanthen-2-yl) diphenylsulfonium A mixture of nonaflate butane sulfonate (sulfonium salt 6) is obtained.
The obtained sulfonium salt 6 is 4-position: 2-position = 6: 4.

<Synthesis of comparative sulfonium salt 1>
(Comparative Synthesis Example 1) Synthesis of (4-methoxy-9-oxo-9H-thioxanthene-1-yl) diphenylsulfonium nonaflatebutanesulfonate (comparative sulfonium salt 1) Instead of 3-methoxythioxanthene-9-one The procedure is the same as in Synthesis Example 4 except that 4-methoxythioxanthene-9-one is used, and an oil containing less than 1% of dication impurities (HPLC Area%) is purified by column chromatography (4-methoxy-9-). Oxo-9H-thioxanthene-2-yl) diphenylsulfonium Nonaflate butane sulfonate is obtained.

<Synthesis of comparative sulfonium salt 2>
(Comparative Synthesis Example 2) Synthesis of (7-fluoro-9-oxo-9H-thioxanthene-2-yl) diphenylsulfonium nonafluorobutanesulfonate (comparative sulfonium salt 2) Instead of 3-methoxythioxanthene-9-one The procedure was the same as in Synthesis Example 4 except that 2-fluorothioxanthene-9-one was used, and the oil containing 41% of dication impurities was purified by column chromatography (7-fluoro-9-oxo-9H-thioxanthene). -2-yl) Diphenylsulfonium Nonafluorobutane sulfonate (comparative sulfonium salt 2) is obtained.

<Synthesis of comparative sulfonium salt 3>
(Comparative Synthesis Example 3) (9-oxo-9H-thioxanthene-2-yl) Synthesis of diphenylsulfonium nonaflatebutanesulfonate Except for using thioxanthene-9-one instead of 3-methoxythioxanthene-9-one. The same procedure as in Synthesis Example 4 was carried out, and the oil containing 51% of dication impurities was purified by column chromatography (9-oxo-9H-thioxanthene-2-yl) diphenylsulfonium nonaflatebutane sulfonate (comparative sulfonium salt 3). To get.

As shown in the above synthesis example and comparative synthesis example, when a sulfonium group is introduced into a thioxanthone derivative in order to synthesize a sulfonium salt having a thioxanthone skeleton, when a thioxanthone derivative having an unsubstituted or 2-position substituent is used, a dication is used. The production rate of monocations is high, and the yield of monocations tends to decrease. In order to obtain a monocation as a target product, it is effective to have a specific substituent at the 3-position of the thioxanthone derivative because the formation of a dication can be suppressed.

<Synthesis of Polymer A>
(Synthesis Example 10) Synthesis of Polymer A 7.0 g of ethylcyclopentyl methacrylate, 5.8 g of 2-methoxyethyl methacrylate, 3.8 g of methoxypolyethylene glycol methacrylate (light ester 130MA), and azobisisobutyronitrile (AIBN). ) 0.21 g and 42 g of propylene glycol monomethyl ether acetate (PGMEA) were dissolved, and degassed under reduced pressure. This is added dropwise to a flask in which 15 g of PGMEA is refluxed over 4 hours. After the dropping, the mixture was stirred for 2 hours and then cooled to 25 ° C. This solution was reprecipitated by dropping into a mixed solvent consisting of 260 g of hexane and 28 g of PGMEA. This is filtered, dispersed and washed twice with 67 g of hexane, and vacuum dried after filtration to obtain 12.7 g of the target polymer A as a white powder. In the present invention, the monomer ratio of the polymer unit is not limited to the following.

<Synthesis of polymer B>
(Synthesis Example 11) Synthesis of Polymer B 7.0 g of acetoxystyrene, 2.1 g of t-butyl methacrylate, 0.022 g of butyl mercaptan and 0.40 g of dimethyl-2,2'-azobis (2-methylpropio) Nate) (AIBN) is dissolved in 35 g of tetrahydrofuran (THF) and deoxidized. This is added dropwise over 4 hours in 20 g of THF which has been set to a reflux temperature by nitrogen airflow in advance. After dropping, the mixture is stirred for 2 hours and then cooled to room temperature. The polymer is precipitated by dropping this in a mixed solvent of 149 g of hexane and 12 g of THF. This is separated by vacuum filtration, and the obtained solid is washed with 52 g of hexane and then vacuum dried to obtain 10.3 g of polymer B represented by the following formula as a white solid. The weight average molecular weight determined by polystyrene conversion using gel permeation chromatography is 9200. In the present invention, the monomer ratio of the polymer unit is not limited to the following.

<Synthesis of Polymer C>
(Synthesis Example 12) Synthesis of Polymer C 6.0 g of Polymer B, 6.0 g of triethylamine, 6.0 g of methanol and 1.5 g of pure water are dissolved in 30 g of propylene glycol monomethyl ether and stirred at a reflux temperature for 6 hours. Then, the mixture is cooled to 25 ° C., and the obtained solution is added dropwise to a mixed solution of 30 g of acetone and 30 g of pure water to precipitate the polymer. This is separated by vacuum filtration, and the obtained solid is washed twice with 30 g of pure water and then vacuum dried to obtain 4.3 g of polymer C represented by the following formula as a white solid. The weight average molecular weight determined by polystyrene conversion using gel permeation chromatography is 9100. In the present invention, the monomer ratio of the polymer unit is not limited to the following.

<Synthesis of Polymer D>
(Synthesis Example 13) Synthesis of Polymer D 8.0 g of polyhydroxystyrene (weight average molecular weight 8000) and 0.010 g of a 35 mass% hydrochloric acid aqueous solution are dissolved in 28 g of dehydrated dioxane. There, 2.73 g of cyclohexyl vinyl ether is dissolved in 2.80 g of dehydrated dioxane and added dropwise to the polyhydroxystyrene solution over 30 minutes. After dropping, the mixture is stirred at 40 ° C. for 2 hours. After stirring and cooling, 0.014 g of dimethylaminopyridine is added. The polymer is then precipitated by dropping the solution into 260 g of pure water. This is separated by vacuum filtration, and the obtained solid is washed twice with 300 g of pure water and then vacuum dried to obtain 9.2 g of the polymer D shown below as a white solid. In the present invention, the monomer ratio of the polymer unit is not limited to the following.

<Measurement of molar extinction coefficient>
15.0 mg each of the above sulfonium salt 1 and the above comparative sulfonium salts 1 to 3 are collected and diluted with chloroform to 25 ml using a 25 ml volumetric flask. 0.5 ml of each sulfonium salt-containing solution is collected with a whole pipette and further diluted with chloroform to 5 ml using a 5 ml volumetric flask. ^{The molar extinction coefficient [mol / cm 2} ] at 365 nm is determined by measuring the absorption spectrum of the obtained solution using an ultraviolet-visible spectrophotometer (U-3300, manufactured by Hitachi High-Technologies Corporation). Further, the molar extinction coefficient is similarly determined for the comparative sulfonium salt 4 (dication) and the comparative sulfonium salt 5 shown below.
These results are shown in Table 1 and FIG.

The following can be seen from the results of the above Examples and Comparative Examples. That is, the sulfonium salt 1 of Example 1 tends to have a shorter absorption wavelength than the comparative sulfonium salt 5 which does not have a specific substituent at the 3-position because it has a specific substituent at the 3-position of the thioxanthone skeleton. is there. The sulfonium salt 1 of Example 1 has a λmax of around 365 nm and a large absorption at 365 nm, so that acid generation becomes dominant in irradiation at 365 nm. Further, the sulfonium salts 1 to 6, which are one aspect of the present invention, have a low dication at the time of synthesis and a high yield of monocation. Comparison When it becomes a dication like sulfonium 4, the absorption tends to be significantly shortened, and the absorption at 365 nm tends to be significantly reduced. As a result, the comparative sulfonium 4 is disadvantageous in acid generation. Therefore, the sulfonium salt in one embodiment of the present invention has a specific substituent at the 3-position to enhance absorption at 365 nm. In addition, since the structure is such that a dication structure is unlikely to occur in synthesis, it can be expected to have higher performance as an acid generator.

<Sensitivity evaluation>
Samples 1 to 13 were prepared as follows. To 3000 mg of cyclohexanone, 500 mg of any resin selected from the polymers A, C and D, and 0.036 mmol of any of the above sulfonium salts 1 and 3 and the comparative sulfonium salts 1 to 5 as a photoacid generator (PAG). , 0.0012 mmol of trioctylamine as a quencher, 0.3 mg of a fluorine-based surfactant (product name: Novac FC-4434, manufactured by 3M), and 0.0015 mmol of salicylic acid as an organic carboxylic acid. Samples were prepared by adding at the ratio of.
Hexamethyldisilazane (HMDS-treated Si wafers) were coated with each of the evaluation samples 1 to 13 in advance, spin-coated, and heated at 110 ° C. to obtain a resist film having a film thickness of 500 nm.
Next, the evaluation sample was exposed with a UV exposure apparatus having a emission line of 365 nm through a 1: 1 line having a line width half pitch of 50 μm and a space pattern mask at different exposure amounts. It was then heated on a hot plate at 110 ° C. for 1 minute.
After heating, develop with a developing solution (product name: NMD-3, 2.38% by mass aqueous solution of tetramethylammonium hydroxide, manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 1 minute, develop, and rinse with pure water. I got a pattern. This was observed with a microscope, and the exposure amount at which the resist was completely peeled off was defined as E size (minimum exposure amount). Table 2 shows the results of evaluating the minimum exposure amount as the sensitivity.

Samples 1, 8 and 10 containing the sulfonium salt 1 were more sensitive than the comparative sulfonium salt 5 having no specific substituent at the 3-position. Instead of the 3-position, the comparative sulfonium salt 1 in which a methoxy group is added at the 4-position, the comparative sulfonium salt 2 in which a fluorine atom is added at the 2-position, and the comparative sulfonium salt 4 having a dication structure are all acids by exposure. Although it was confirmed that it occurred, it was insufficient even after exposure to ^{500 mJ / cm 2.} Comparative sulfonium salts 3, 5 are more sensitive than comparative sulfonium salts 1, 2, and 4, but less sensitive than the sulfonium salts of the present invention. Furthermore, since these comparative sulfonium salts do not have a structure having a specific substituent at the 3-position in synthesis, they tend to generate a large amount of dications. When industrially producing an acid generator, it is preferable that the yield of the target product is high due to the reaction selectivity, and that the dication having low sensitivity can be used without performing a removal step such as column purification. Therefore, the sulfonium salt according to one aspect of the present invention in which the formation of dications can be suppressed is effective because it can maintain high sensitivity even when it is produced by a method that does not go through a purification step.

According to some aspects of the present invention, there is provided a sulfonium salt preferably used as a photoacid generator for improving acid generation efficiency and obtaining a photoresist having high sensitivity, and a resist composition containing the sulfonium salt. Can be done.

Claims (5)

A sulfonium salt represented by the following general formula (1) or general formula (2).

(In the above formula (1), R ¹ and R ² each independently have a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms; which may have a substituent. It has a linear, branched or cyclic alkenyl group having 1 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and a substituent. A heteroaryl group having 4 to 12 carbon atoms; whichever is selected from the group consisting of
At ^{least one methylene group in R 1} and R ² may be substituted with a divalent heteroatom-containing group.
The R ¹ and R ² form a ring structure together with the sulfur atom to which they are bonded, either directly in a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and a methylene group. Well,
R ³ is a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent. Alkenyl groups to 12; linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms which may have substituents; aryloxy having 6 to 12 carbon atoms which may have substituents. Group; Heteroaryloxy group having 4 to 12 carbon atoms which may have a substituent; Linear, branched or cyclic alkylsulfanyl group having 1 to 12 carbon atoms which may have a substituent; An arylsulfanyl group having 6 to 12 carbon atoms which may have a substituent; a heteroarylsulfanyl group having 4 to 12 carbon atoms which may have a substituent; may have a substituent. A linear, branched or cyclic alkylsulfonyl group having 1 to 12 carbon atoms; an arylsulfonyl group having 6 to 12 carbon atoms which may have a substituent; and a carbon which may have a substituent. It is one selected from the group consisting of heteroarylsulfonyl groups having 4 to 12 atoms;
Each of R ⁴ and R ⁵ independently has a hydrogen atom; a hydroxyl group; a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; a substituent. It may have a linear, branched or cyclic alkenyl group having 1 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and may have a substituent. Heteroaryl group having 4 to 12 carbon atoms; branched or cyclic alkylcarbonyloxy group having 1 to 12 carbon atoms which may have a substituent; linear, branched or which may have a substituent. Cyclic alkenylcarbonyloxy group having 1 to 12 carbon atoms; arylcarbonyloxy group having 6 to 12 carbon atoms which may have a substituent; 4 to 12 carbon atoms which may have a substituent Heteroarylcarbonyloxy group; any of the groups selected from the group consisting of
R ⁶ is a halogen atom; a hydroxyl group; a nitro group; an optionally substituted linear, minute岐又alkyl group having 1 to 12 carbon atoms in the ring; which may have a substituent linear , A branched or cyclic alkenyl group having 1 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and an aryl group having 4 to 14 carbon atoms which may have a substituent. Heteroaryl group; linear, branched or cyclic alkoxy group having 1 to 12 carbon atoms which may have a substituent; aryloxy group having 1 to 12 carbon atoms which may have a substituent; A linear, branched or cyclic alkyl sulfanyl group having 1 to 12 carbon atoms which may have a substituent; an aryl sulfanyl group having 1 to 12 carbon atoms which may have a substituent; It has a linear, branched or cyclic alkylsulfonyl group having 1 to 12 carbon atoms; an arylsulfonyl group having 6 to 12 carbon atoms which may have a substituent; and a substituent. Heteroaryl group having 4 to 12 carbon atoms which may have a substituent; linear, branched or cyclic alkylcarbonyloxy group having 1 to 12 carbon atoms which may have a substituent; A linear, branched or cyclic alkenylcarbonyloxy group having 1 to 12 carbon atoms; optionally having a substituent; an arylcarbonyloxy group having 6 to 12 carbon atoms; having a substituent. A heteroarylcarbonyloxy group having 4 to 12 carbon atoms; whichever is selected from the group consisting of
At ^{least one methylene group in R 4} , R ⁵ and R ⁶ may be substituted with a divalent heteroatom-containing group.
n is an integer from 0 to 4
^{At least two of R 1 to} R ⁵ described above form a ring structure together with the sulfur atom to which they are bonded, either directly in a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and a methylene group. May be formed,
At least two of the two or more R ⁶ is directly a single bond or an oxygen atom, may form a ring structure via one selected from the group consisting of a sulfur atom and a methylene group,
And X ^- represents a monovalent counter anion.
In the formula (2), R ^{1 to} R ⁴ , R ⁶ , X ⁻ and n are the same as the options ^{of R 1 to} R ⁴ , R ⁶ , X ^{− and n in the formula (1).} ) The photoacid generator containing the sulfonium salt according to claim 1. A composition comprising the photoacid generator according to claim 2 and an acid-reactive compound. The composition according to claim 3, further comprising a polymer having a hydroxyaryl group-containing unit. A step of forming a resist film on a substrate using the composition according to any one of claims 3 to 4.
The step of irradiating the resist film with active energy rays and
A method for manufacturing a device including the step of developing the resist film.

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