JP5046965B2 - Positive resist composition and pattern forming method using the same - Google Patents

Description

  The present invention relates to a positive resist composition suitably used in an ultramicrolithography process such as the manufacture of VLSI and high-capacity microchips and other photo-publishing processes, and a pattern forming method using the same. More specifically, the present invention relates to a positive resist composition capable of forming a high-definition pattern using KrF excimer laser light, electron beam, EUV light, and the like, and a pattern forming method using the same. KrF excimer laser light, The present invention relates to a positive resist composition that can be suitably used for microfabrication of a semiconductor device using an electron beam or EUV light, and a pattern forming method using the same.

  Conventionally, in the manufacturing process of semiconductor devices such as IC and LSI, fine processing by lithography using a photoresist composition has been performed. In recent years, with the high integration of integrated circuits, the formation of ultrafine patterns in the submicron region and the quarter micron region has been required. Along with this, there is a tendency to shorten the exposure wavelength from g-line to i-line and further to KrF excimer laser light. Furthermore, at present, in addition to excimer laser light, lithography using electron beams, X-rays, or EUV light is also being developed.

  Further, in lithography used for an ion implantation process using KrF excimer laser light, it is also important to satisfy high resolution and good density dependence at the same time, and these solutions are necessary.

  As a resist suitable for the lithography process used in these ion implantation processes, as shown in Patent Documents 1 to 5, the light transmittance of the resist film is adjusted from the viewpoint of resist pattern shape control on a highly reflective substrate. Chemically amplified resists have been studied, and in the positive resist, as a main component, a phenolic polymer having a property of being insoluble or hardly soluble in an antari developer and soluble in an antari developer by the action of an acid ( Hereinafter, a chemically amplified resist composition comprising a phenolic acid-decomposable resin), an acid generator, and a dye for adjusting light transmittance is effective. It is also known that a dye for adjusting light transmittance is connected to a phenolic acid-decomposable resin. Here, an anthracene structure, a benzene carboxylic acid structure, a naphthalene carboxylic acid structure, a thiophene structure, and the like are known as dyes for adjusting light transmittance.

  However, in any combination of these, the present situation is that high resolution, scum, density bias, and standing wave reduction in the ultrafine region are not satisfactory.

JP-A-7-84364 JP 7-316268 A JP 7-319155 A Japanese Patent Laid-Open No. 10-186647 JP 2006-328241 A

An object of the present invention is to solve the problem of performance improvement technology in microfabrication of a semiconductor device using actinic rays or radiation, particularly KrF excimer laser light, electron beam or EUV light. To provide a positive resist composition that satisfies high resolution, scum, density bias, and standing wave reduction even in an ion implantation process that does not use a barrier film (BARC), and a pattern forming method using the same. .

一般式（Ｉａ）に於いて、
Ｘは、水素原子、メチル基又はハロゲン原子を表す。
Ｑ _１ は、アリールカルボニル基を表す。ｎが２〜３の場合に、複数個のＱ _１ は、同じでも異なっていてもよい。
Ｌは、一価の有機基、ハロゲン原子、シアノ基又はニトロ基を表す。ｍが２の場合に、２個のＬは、同じでも異なっていてもよい。
ｎは、１〜３の整数を表す。
ｍは、０〜２の整数を表す。
一般式（Ｉｂ）に於いて、
Ｘは、水素原子、メチル基又はハロゲン原子を表す。
Ｑ _２ は、アリールカルボニル基を表す。
Ｚ _２ は、２価の連結基を表す。

一般式（ＩＩ）に於いて、
Ｙは、水素原子、メチル基、ハロゲン原子、シアノ基、ヒドロキシメチル基、アルコキシメチル基又はアシルオキシメチル基を表す。
Ａは、酸の作用により脱離する基を表す。
ただし、上記樹脂（Ｂ）から、下記一般式（１）で表される繰り返し単位、下記一般式（２）で表される繰り返し単位、及び、下記一般式（３）で表される繰り返し単位のみからなる樹脂を除く。

一般式（１）において、
Ｒ _１ は、水素原子、メチル基、シアノ基、ハロゲン原子又は炭素数１〜４のペルフルオ
ロアルキル基を表す。
Ｒ _２ 及びＲ _３ は、各々独立に、アルキル基を表す。
Ｘは、脂環式基を表す。
一般式（２）において、
Ｒ _４ は、水素原子、メチル基、シアノ基、ハロゲン原子又は炭素数１〜４のペルフルオ
ロアルキル基を表す。
Ｒ _５ は、アルキル基、ハロゲン原子、アリール基、アルコキシ基又はアシル基を表す。
ｌは、０〜４の整数を表す。
一般式（３）において、
Ｒ _６ は、水素原子、メチル基、シアノ基、ハロゲン原子又は炭素数１〜４のペルフルオ
ロアルキル基を表す。
Ｒ _７ は、アルキル基、ハロゲン原子、アリール基、アルコキシ基又はアシル基を表す。
Ｒ _８ は、アリール基を表す。
ｍは、０〜４の整数を表す。
ｎは、１〜５の整数を表す。
〔２〕
樹脂（Ｂ）が、更に、下記一般式（ＩＩＩ）で表される繰り返し単位を有することを特徴とする〔１〕に記載のポジ型レジスト組成物。

一般式（ＩＩＩ）に於いて、
Ｘは、水素原子、メチル基又はハロゲン原子を表す。
Ｒは、水素原子又は酸の作用により脱離する基を表す。
Ｌは、一価の有機基、ハロゲン原子、シアノ基又はニトロ基を表す。
ｎは、１〜３の整数を表す。
ｍは、０〜２の整数を表す。
〔３〕
樹脂（Ｂ）が、更に、下記一般式（ＩＶ）で表される繰り返し単位を有することを特徴とする〔１〕又は〔２〕のいずれかに記載のポジ型レジスト組成物。

一般式（ＩＶ）に於いて、
Ｒ _１ は、水素原子、アルキル基、シアノ基又はハロゲン原子を表す。
Ｒ _３ は、酸の作用による分解性を有さない１価の有機基、ハロゲン原子又はニトロ基を表す。
ｐは、０〜５の整数を表す。ｐが２以上の場合に複数個のＲ _３ は、それぞれ異なっていてもよい。
〔４〕
活性光線又は放射線の照射により酸を発生する化合物（Ａ）が、ジアゾジスルホン又はオキシムエステルであることを特徴とする〔１〕〜〔３〕のいずれかに記載のポジ型レジスト組成物。
〔５〕
活性光線又は放射線の照射により酸を発生する化合物（Ａ）が、ビス（アルキルスルホニル）アミドアニオン又はトリス（アルキルスルホニル）メチドアニオンを有するスルホニウム塩であることを特徴とする〔１〕〜〔３〕のいずれかに記載のポジ型レジスト組成物。
〔６〕
〔１〕〜〔５〕のいずれかに記載のポジ型レジスト組成物により形成されるレジスト膜。
〔７〕
〔６〕に記載のレジスト膜を露光、現像する工程を含むことを特徴とするパターン形成方法。
本発明は上記の〔１〕〜〔７〕に関するものであるが、その他の事項についても記載した。 The inventors of the present invention have arrived at the present invention as a result of intensive studies to solve the above problems.
The present invention is as follows.
[1]
It has a repeating unit represented by the following general formula (Ia) or (Ib), and further has a repeating unit represented by the following general formula (II). A positive resist composition comprising an increasing resin (B) and a compound (A) that generates an acid upon irradiation with actinic rays or radiation.

In general formula (Ia):
X represents a hydrogen atom, a methyl group or a halogen atom.
Q ₁ represents an arylcarbonyl group. When n is 2 to 3, the plurality of Q ₁ may be the same or different.
L represents a monovalent organic group, a halogen atom, a cyano group, or a nitro group. When m is 2, two Ls may be the same or different.
n represents an integer of 1 to 3.
m represents an integer of 0 to 2.
In general formula (Ib):
X represents a hydrogen atom, a methyl group or a halogen atom.
Q ₂ represents an arylcarbonyl group.
Z ₂ represents a divalent linking group.

In general formula (II):
Y represents a hydrogen atom, a methyl group, a halogen atom, a cyano group, a hydroxymethyl group, an alkoxymethyl group or an acyloxymethyl group.
A represents a group capable of leaving by the action of an acid.
However, from the resin (B), only the repeating unit represented by the following general formula (1), the repeating unit represented by the following general formula (2), and the repeating unit represented by the following general formula (3) The resin consisting of is excluded.

In general formula (1),
R ₁ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom, or a perfluoro having 1 to 4 carbon atoms.
Represents a loalkyl group.
R ₂ and R ₃ each independently represents an alkyl group.
X represents an alicyclic group.
In general formula (2),
R ₄ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom, or a perfluoro having 1 to 4 carbon atoms.
Represents a loalkyl group.
R ₅ represents an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group.
l represents an integer of 0 to 4.
In general formula (3),
R ₆ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom, or a perfluoro having 1 to 4 carbon atoms.
Represents a loalkyl group.
R ₇ represents an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group.
R ₈ represents an aryl group.
m represents an integer of 0 to 4.
n represents an integer of 1 to 5.
[2]
The positive resist composition as described in [1], wherein the resin (B) further has a repeating unit represented by the following general formula (III).

In general formula (III):
X represents a hydrogen atom, a methyl group or a halogen atom.
R represents a hydrogen atom or a group capable of leaving by the action of an acid.
L represents a monovalent organic group, a halogen atom, a cyano group, or a nitro group.
n represents an integer of 1 to 3.
m represents an integer of 0 to 2.
[3]
The positive resist composition as described in either [1] or [2], wherein the resin (B) further has a repeating unit represented by the following general formula (IV).

In general formula (IV),
R ₁ represents a hydrogen atom, an alkyl group, a cyano group or a halogen atom.
R ₃ represents a monovalent organic group that does not have decomposability due to the action of an acid, a halogen atom, or a nitro group.
p represents an integer of 0 to 5. When p is 2 or more, the plurality of R ₃ may be different from each other.
[4]
The positive resist composition as described in any one of [1] to [3], wherein the compound (A) that generates an acid upon irradiation with actinic rays or radiation is diazodisulfone or oxime ester.
[5]
The compound (A) that generates an acid upon irradiation with actinic rays or radiation is a sulfonium salt having a bis (alkylsulfonyl) amide anion or a tris (alkylsulfonyl) methide anion. The positive resist composition according to any one of the above.
[6]
[1] A resist film formed from the positive resist composition according to any one of [5].
[7]
[6] A pattern forming method comprising a step of exposing and developing the resist film according to [6].
The present invention relates to the above [1] to [7], but other matters are also described.

(1) Resin (B) having a repeating unit represented by the following general formula (Ia) or (Ib), which decomposes by the action of an acid and increases its solubility in an alkaline aqueous solution, and an acid by irradiation with actinic rays or radiation A positive resist composition comprising a compound (A) that generates water.

In general formula (Ia):
X represents a hydrogen atom, a methyl group or a halogen atom.
Q ₁ represents an arylcarbonyl group. When n is 2 to 3, the plurality of Q ₁ may be the same or different.
L represents a monovalent organic group, a halogen atom, a cyano group, or a nitro group. When m is 2, two Ls may be the same or different.
n represents an integer of 1 to 3.
m represents an integer of 0 to 2.
In general formula (Ib):
X represents a hydrogen atom, a methyl group or a halogen atom.
Q ₂ represents an arylcarbonyl group.
Z ₂ represents a divalent linking group.

  (2) The positive resist composition as described in (1), wherein the resin (B) further has a repeating unit represented by the following general formula (II).

In general formula (II):
Y represents a hydrogen atom, a methyl group, a halogen atom, a cyano group, a hydroxymethyl group, an alkoxymethyl group or an acyloxymethyl group.
A represents a group capable of leaving by the action of an acid.

  (3) The positive resist composition as described in (1) or (2), wherein the resin (B) further has a repeating unit represented by the following general formula (III).

In general formula (III):
X represents a hydrogen atom, a methyl group or a halogen atom.
R represents a hydrogen atom or a group capable of leaving by the action of an acid.
L represents a monovalent organic group, a halogen atom, a cyano group, or a nitro group.
n represents an integer of 1 to 3.
m represents an integer of 0 to 2.

  (4) The positive resist composition as described in any one of (1) to (3), wherein the resin (B) further has a repeating unit represented by the following general formula (IV).

In general formula (IV),
R ₁ represents a hydrogen atom, an alkyl group, a cyano group or a halogen atom.
R ₃ represents a monovalent organic group, a halogen atom or a nitro group that does not have decomposability due to the action of an acid.
p represents an integer of 0 to 5. When p is 2 or more, the plurality of R ₃ may be different from each other.

  (5) The positive resist composition according to any one of (1) to (4), wherein the compound (A) that generates an acid upon irradiation with actinic rays or radiation is diazodisulfone or oxime ester. .

  (6) The compound (A) that generates an acid upon irradiation with actinic rays or radiation is a sulfonium salt having a bis (alkylsulfonyl) amide anion or a tris (alkylsulfonyl) methide anion (1) to ( 4) The positive resist composition according to any one of the above.

  (7) A pattern forming method comprising: forming a resist film from the positive resist composition according to any one of (1) to (6); and exposing and developing the resist film.

  According to the present invention, a positive resist that simultaneously satisfies high resolution, good density dependency, development defects, and reduction of standing waves even in an ion implantation process that does not use an antireflection film (BARC), in an ultrafine region. A composition and a pattern forming method using the composition can be provided.

Hereinafter, the present invention will be described in detail.
In addition, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes what has a substituent with what does not have a substituent. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

(B) Resin having a repeating unit represented by the general formula (Ia) or (Ib), which is decomposed by the action of an acid and increases the solubility in an alkaline aqueous solution. The positive resist composition of the present invention has the following general formula It contains a resin (also referred to as “resin (B)”) having a repeating unit represented by (Ia) or (Ib), which is decomposed by the action of an acid to increase the solubility in an alkaline aqueous solution.

In general formula (Ia):
X represents a hydrogen atom, a methyl group or a halogen atom.
Q ₁ represents an arylcarbonyl group. When n is 2 to 3, the plurality of Q ₁ may be the same or different.
L represents a monovalent organic group, a halogen atom, a cyano group, or a nitro group. When m is 2, two Ls may be the same or different.
n represents an integer of 1 to 3.
m represents an integer of 0 to 2.
In general formula (Ib):
X represents a hydrogen atom, a methyl group or a halogen atom.
Q ₂ represents an arylcarbonyl group.
Z ₂ represents a divalent linking group.

In the general formulas (Ia) and (Ib), the aryl group of the arylcarbonyl group of Q ₁ and Q ₂ is preferably an aryl group having 6 to 20 carbon atoms, more preferably a phenyl group, a naphthyl group, or an anthranyl group. . The aryl group may have a substituent. Examples of the substituent include an alkyl group, an aralkyl group, an aryl group, an acyl group, an alkoxy group, an acyloxy group, a hydroxyl group, a halogen atom, a cyano group, a nitro group, and a carboxyl group. Examples include acid ester groups and sulfonic acid ester groups. As the alkyl group, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, octyl group, dodecyl group, etc. are preferable. Includes a linear or branched alkyl group having 1 to 20 carbon atoms. The aralkyl group preferably has 7 to 20 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group. The aryl group preferably has 6 to 20 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthranyl group.
Examples of the monovalent organic group for L include an alkyl group, an aralkyl group, an aryl group, an acyl group, an alkoxy group, and an acyloxy group.
Specific examples of the divalent linking group for Z ₂ include alkylene groups, aralkylene groups, arylene groups, divalent heterocyclic groups, ether groups, ester groups, amide groups, urethane groups, ureido groups, and sulfide groups. These may be used in combination. A group having an alkylene group, an aralkylene group or an arylene group is preferred, and a group having an alkylene group, an aralkylene group or an arylene group is more preferred. The alkylene group preferably has 1 to 10 carbon atoms, the aralkylene group has 7 to 20 carbon atoms, and the arylene group preferably has 6 to 20 carbon atoms. As the heterocyclic ring of the divalent heterocyclic group, a furan ring and a thiophene ring are preferable.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable.

  Specific examples of the repeating unit represented by the general formula (Ia) or (Ib) are shown below, but are not limited thereto.

  The resin (B) preferably further has a repeating unit represented by the following general formula (II) or (III).

In general formula (II):
Y represents a hydrogen atom, a methyl group, a halogen atom, a cyano group, a hydroxymethyl group, an alkoxymethyl group or an acyloxymethyl group.
A represents a group capable of leaving by the action of an acid.

In general formula (III):
X represents a hydrogen atom, a methyl group or a halogen atom.
R represents a hydrogen atom or a group capable of leaving by the action of an acid.
L represents a monovalent organic group, a halogen atom, a cyano group, or a nitro group.
n represents an integer of 1 to 3.
m represents an integer of 0 to 2.

In general formula (II), the group capable of leaving by the action of an acid of A is preferably a hydrocarbon group (preferably having 20 or less carbon atoms, more preferably 4 to 12), a t-butyl group, A hydrocarbon group having a t-amyl group, an alicyclic ring or an aromatic ring (for example, a group in which the alicyclic group is substituted on the alicyclic group itself or an alkyl group) is more preferable.
The alicyclic structure may be monocyclic or polycyclic. Specific examples include monocyclo, bicyclo, tricyclo, and tetracyclo structures having 5 or more carbon atoms. The carbon number is preferably 6-30, and particularly preferably 7-25. These hydrocarbon groups having an alicyclic structure may have a substituent.
In the present invention, the alicyclic structure is preferably a monovalent alicyclic group as an adamantyl group, a noradamantyl group, a decalin residue, a tricyclodecanyl group, a tetracyclododecanyl group, norbornyl. Group, cedrol group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecanyl group, and cyclododecanyl group. More preferred are an adamantyl group, a decalin residue, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, and a cyclododecanyl group.

  Examples of the substituent that the alicyclic ring may have include an alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycarbonyl group. The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group or a butyl group, more preferably a methyl group, an ethyl group, a propyl group or an isopropyl group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. The alkyl group and the alkoxy group may have a further substituent. Examples of further substituents on the alkyl group and alkoxy group include a hydroxyl group, a halogen atom, and an alkoxy group.

  As the group capable of leaving by the action of an acid having an alicyclic structure, groups represented by the following general formulas (pI) to (pV) are preferable.

In the general formulas (pI) to (pV),
R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a sec-butyl group.
Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with a carbon atom.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. However, at least one of R _{12 to} R ₁₄ , or any of R ₁₅ and R ₁₆ represents an alicyclic hydrocarbon group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group. However, at least one of R _{17 to} R ₂₁ represents an alicyclic hydrocarbon group. In addition, any of R ₁₉ and R ₂₁ represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group. However, at least one of R _{22 to} R ₂₅ represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

In the general formulas (pI) to (pV), examples of the alkyl group in R _{12 to} R ₂₅ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, A sec-butyl group, a t-butyl group, etc. are mentioned.
As further substituents of the alkyl group, an alkoxy group having 1 to 4 carbon atoms, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), acyl group, acyloxy group, cyano group, hydroxyl group, carboxy group , Alkoxycarbonyl group, nitro group and the like.

Examples of the alicyclic hydrocarbon group in R _{12 to} R _{25 or} the alicyclic hydrocarbon group formed by Z and a carbon atom include those described above as the alicyclic structure.

  Specific examples of the group capable of leaving by the action of an acid having an alicyclic structure as A will be given below, but the present invention is not limited thereto.

  As the group capable of leaving by the action of an acid having an aromatic ring, a group represented by the following general formula (pVI) is preferable.

In general formula (pVI):
R ₂₆ represents an alkyl group.
R ₂₇ represents an aryl group.

The alkyl group for R _{26 is the same as} the alkyl group for R _{12 to} R ₂₅ .
The aryl group of R ₂₇ is preferably an aryl group having 6 to 14 carbon atoms, more preferably a phenyl group or a naphthyl group, and has a substituent such as alkyl, aralkyl, halogen, nitro, cyano, hydroxy, alkoxy, acyl, acyloxy and the like. You may do it.

  The monomer corresponding to the repeating unit represented by the general formula (II) includes (meth) acrylic acid chloride and an alcohol compound in a solvent such as THF, acetone, and methylene chloride, and a basic catalyst such as triethylamine, pyridine, and DBU. It can be synthesized by esterification below. A commercially available product may be used.

  Hereinafter, specific examples of the polymerizable monomer corresponding to the repeating unit represented by the general formula (II) or the repeating unit represented by the general formula (II) will be given, but the present invention is limited thereto. is not.

  In the general formula (III), L is the same as L in the general formula (Ia).

In general formula (III), the group capable of leaving by the action of an acid of R is specifically a tertiary alkyl group such as t-butyl group or t-amyl group, t-butoxycarbonyl group, t- Examples thereof include an acetal group represented by a butoxycarbonylmethyl group, -C (L ₁ ) (L ₂ ) -OZ.
L ₁ and L ₂ may be the same or different and each represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aralkyl group.
Z represents an alkyl group, a cycloalkyl group or an aralkyl group.
Z and L ₁ may be bonded to each other to form a 5- or 6-membered ring.
Examples of the alkyl group of L ₁ , L ₂ and Z include, for example, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, pentyl group, hexyl group, octyl group, dodecyl. A linear or branched alkyl group having 1 to 20 carbon atoms such as a group is preferred.
The cycloalkyl group of L _1, L ₂ and Z, for example, cyclopropyl group, cyclobutyl group, cyclopentyl group, a cycloalkyl group having 3 to 20 carbon atoms such as cyclohexyl group.
Examples of the aralkyl group in L ₁ , L ₂ and Z include those having 7 to 15 carbon atoms such as benzyl group and phenethyl group.
These groups may have a substituent. Further preferred substituents that may be included include, for example, alkyl groups, cycloalkyl groups, aryl groups, alkoxy groups, cycloalkoxy groups, aryloxy groups, hydroxyl groups, halogen atoms, nitro groups, acyl groups, acyloxy groups, acylamino groups, Examples include a sulfonylamino group, an alkylthio group, an arylthio group, an aralkylthio group, a thiophenecarbonyloxy group, a thiophenemethylcarbonyloxy group, a pyrrolidone residue, and the like.
Examples of the 5- or 6-membered ring formed by combining Z and L ₁ with each other include a tetrahydropyran ring and a tetrahydrofuran ring.
In the present invention, Z is preferably a linear or branched alkyl group. Thereby, the effect of the present invention becomes more remarkable.

  The monomer corresponding to the repeating unit represented by the general formula (III) is a hydroxy-substituted styrene monomer and a vinyl ether compound in a solvent such as THF and methylene chloride, such as p-toluenesulfonic acid and p-toluenesulfonic acid pyridine salt. It can be synthesized by acetalization in the presence of an acidic catalyst or by t-Boc protection using t-butyl dicarbonate in the presence of a basic catalyst such as triethylamine, pyridine, DBU or the like. A commercially available product may be used.

  Although the specific example of the repeating unit represented by general formula (III) below is given, it is not limited to these.

  The resin (B) preferably further has a repeating unit represented by the following general formula (IV).

In general formula (IV),
R ₁ represents a hydrogen atom, an alkyl group, a cyano group or a halogen atom.
R ₃ represents a monovalent organic group, a halogen atom or a nitro group that does not have decomposability due to the action of an acid.
p represents an integer of 0 to 5. When p is 2 or more, the plurality of R ₃ may be different from each other.

In the general formula (IV), the alkyl group represented by R ₁ is preferably a linear alkyl group having 1 to 4 carbon atoms and may be substituted with a halogen atom (preferably a fluorine atom), a hydroxyl group or the like.

  Specific examples of the monovalent organic group that is not degradable by the action of an acid (also referred to as an acid stabilizing group) include an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, a cyano group, an alkyloxy group, Cycloalkyloxy group, alkenyloxy group, aryloxy group, alkylcarbonyloxy group, cycloalkylcarbonyloxy group, arylcarbonyloxy group, alkylamidomethyloxy group, alkylamido group, arylamidomethyl group, arylamido group, etc. It is done.

  Although the specific example of the repeating unit represented by general formula (IV) below is given, this invention is not limited to these.

The resin (B) is preferably a resin (acid-decomposable resin) whose solubility in an alkali developer is increased by the action of an acid, and is decomposed by the action of an acid in an arbitrary repeating unit. It preferably has a group that generates a soluble group (acid-decomposable group).
The repeating unit represented by the general formula (II) or (III) may have an acid-decomposable group, or may be contained in another repeating unit.
Examples of the acid-decomposable group include those represented by —C (═O) —X ₁ —R ₀ .
In the formula, R ₀ is a tertiary alkyl group such as t-butyl group or t-amyl group, isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxyethyl group, 1-cyclohexyloxy. 1-alkoxyethyl group such as ethyl group, 1-methoxymethyl group, alkoxymethyl group such as 1-ethoxymethyl group, 3-oxoalkyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl ester group, 3- An oxocyclohexyl ester group, a 2-methyl-2-adamantyl group, a mevalonic lactone residue and the like can be mentioned. X ₁ represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or -NHSO ₂
NH- is represented.

The resin (B) may have a combination of two or more repeating units represented by the general formulas (Ia), (Ib), (II), (III) and (IV).
The content of the repeating unit represented by the general formula (Ia) or (Ib) in the resin (B) is preferably 5 to 60 mol%, more preferably 10 to 50 mol% in all repeating units. Especially preferably, it is 15-30 mol%.
The content of the repeating unit represented by the general formula (II) in the resin (B) is preferably 5 to 60 mol%, more preferably 5 to 50 mol%, and particularly preferably 10 to 10 mol% in all repeating units. 35 mol%.
The content of the repeating unit represented by the general formula (III) in the resin (B) is preferably 40 to 90 mol%, more preferably 50 to 85 mol%, and particularly preferably 60 to 85 mol% in all repeating units. 80 mol%.
The resin (B) may further have a repeating unit represented by the general formula (IV), which is preferable from the viewpoints of improving the film quality and suppressing the decrease in film thickness of the unexposed area. The content of the repeating unit represented by the general formula (IV) is preferably 0 to 50 mol%, more preferably 0 to 40 mol%, and particularly preferably 0 to 40 mol% in each of all the repeating units. 30 mol%.

  Resin (B) is copolymerized with other polymerizable monomers suitable so that alkali-soluble groups such as phenolic hydroxyl groups and carboxyl groups can be introduced in order to maintain good developability for an alkali developer. Alternatively, in order to improve the film quality, other hydrophobic polymerizable monomers such as alkyl acrylate and alkyl methacrylate may be copolymerized.

The weight average molecular weight (Mw) of the resin (B) is preferably in the range of 1,000 to 15,000, more preferably in the range of 3,000 to 10,000. Dispersity (Mw /
Mn) is preferably 1.0 to 2.0, more preferably 1.0 to 1.8, and particularly preferably 1.0 to 1.5.
Here, the weight average molecular weight is defined by a polystyrene conversion value of gel permeation chromatography.

  The resin (B) can be obtained by radical or anionic polymerization of a monomer that gives the repeating unit (Ia) or (Ib) alone or with another monomer. It can also be obtained by reacting a resin copolymerized with a hydroxystyrene monomer with an arylcarboxylic acid halide or arylcarboxylic acid anhydride.

Two or more types of resins (B) may be used in combination.
The total amount of the resin (B) added is generally 10 to 96% by mass, preferably 15 to 96% by mass, and particularly preferably 20 to 95% by mass with respect to the total solid content of the positive resist composition. %.

  Although the specific example of resin (B) is given to the following, it is not limited to these.

(A) Compound that generates acid upon irradiation with actinic ray or radiation The positive resist composition of the present invention comprises a compound that generates acid upon irradiation with actinic ray or radiation (hereinafter referred to as “acid generator” or “(A)”. Component ").
Examples of such an acid generator include a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photodecolorant for dyes, a photochromic agent, or an actinic ray or radiation used for a microresist. A known compound that generates an acid by irradiation and a mixture thereof can be appropriately selected and used.

  Examples thereof include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.

  Further, a group that generates an acid upon irradiation with these actinic rays or radiation, or a compound in which a compound is introduced into the main chain or side chain of the polymer, for example, US Pat. No. 3,849,137, German Patent No. 3914407. JP, 63-26653, JP, 55-164824, JP, 62-69263, JP, 63-146038, JP, 63-163452, JP, 62-153853, The compounds described in JP-A 63-146029 can be used.

Furthermore, compounds capable of generating an acid by light described in US Pat. No. 3,779,778, European Patent 126,712 and the like can also be used.

  Among the compounds that generate an acid upon irradiation with actinic rays or radiation, compounds represented by the following general formulas (ZI), (ZII), and (ZIII) can be exemplified.

In general formula (ZI):
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
X ⁻ represents a non-nucleophilic anion, preferably sulfonate anion, carboxylate anion, bis (alkylsulfonyl) amide anion, tris (alkylsulfonyl) methide anion, BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ^{− and the} like. Preferably, it is an organic anion containing a carbon atom.

  Preferable organic anions include organic anions represented by the following general formulas (AN1) to (AN4).

In the general formula (AN1- (AN2),
Rc ₁ represents an organic group.

Examples of the organic group in Rc ₁ include those having 1 to 30 carbon atoms, and preferably an alkyl group, a cycloalkyl group, an aryl group, or a plurality of these which may be substituted is a single bond, —O—. , —CO ₂ —, —S—, —SO ₃ —, —SO ₂ N (Rd ₁ ) — and the like. Rd ₁ represents a hydrogen atom or an alkyl group, and may form a ring structure with a bonded alkyl group, cycloalkyl group, or aryl group.
More preferably, the organic group of Rc ₁ is substituted at the 1-position with an alkyl group substituted with a fluorine atom or a fluoroalkyl group, a cycloalkyl group substituted with a fluorine atom or a fluoroalkyl group, a fluorine atom or a fluoroalkyl group An aryl group (preferably a phenyl group). By having a fluorine atom or a fluoroalkyl group, the acidity of the acid generated by light irradiation is increased and the sensitivity is improved. When Rc ₁ has 5 or more carbon atoms, it is preferable that at least one carbon atom does not have all hydrogen atoms replaced with fluorine atoms, but leaves some hydrogen atoms. More preferably, there are more hydrogen atoms than fluorine atoms. By not having a perfluoroalkyl group having 5 or more carbon atoms, ecotoxicity is reduced.

As a particularly preferred embodiment of Rc ₁ , groups represented by the following general formula can be exemplified.

In the above general formula,
Rc ₆ is substituted with a perfluoroalkylene group having 4 or less carbon atoms, more preferably 2 to 4 carbon atoms, more preferably 2 to 3 carbon atoms, 1 to 4 fluorine atoms and / or 1 to 3 fluoroalkyl groups. Represents a phenylene group.
Ax represents a single bond or a divalent linking group (preferably —O—, —CO ₂ —, —S—, —SO ₃ —, —SO ₂ N (Rd ₁ ) —). Rd ₁ represents a hydrogen atom or an alkyl group, and may combine with Rc ₇ to form a ring structure.
Rc ₇ represents a hydrogen atom, a fluorine atom, a linear optionally substituted or branched alkyl group, optionally substituted monocyclic or polycyclic cycloalkyl group, or an optionally substituted aryl group . The alkyl group, cycloalkyl group and aryl group which may be substituted preferably have no fluorine atom as a substituent.

In the general formulas (AN3) to (AN4),
Rc ₃ , Rc ₄ and Rc ₅ each independently represents an organic group.

Preferred examples of the organic group for Rc ₃ , Rc ₄ and Rc ₅ include the same organic groups as those for Rc ₁ .
Rc ₃ and Rc ₄ may combine to form a ring.
Examples of the group formed by combining Rc ₃ and Rc ₄ include an alkylene group, a cycloalkylene group, and an arylene group. Preferably, it is a C2-C4 perfluoroalkylene group. Rc ₃ and Rc ₄ are preferably bonded to form a ring, so that the acidity of the acid generated by light irradiation is increased and the sensitivity is improved, which is preferable.

In the general formula (ZI), the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.
Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group.
The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).
Specific examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include a compound (ZI-1) described later.
), (ZI-2) and (ZI-3).

The compound which has two or more structures represented by general formula (Z1) may be sufficient. For example, the general formula (
At least one of R ₂₀₁ to R ₂₀₃ of a compound represented by ZI) is a compound having a structure bonded to at least one of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (ZI) Also good.

  More preferable (ZI) components include compounds (ZI-1), (ZI-2), and (ZI-3) described below.

The compound (ZI-1) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (ZI), arylsulfonium compound, i.e., a compound having arylsulfonium as a cation.
In the arylsulfonium compound, all of R _{201 to} R ₂₀₃ may be an aryl group, or R ₂₀₁
Some of to R ₂₀₃ is an aryl group with the remaining being an alkyl group or a cycloalkyl group.
Examples of the arylsulfonium compound include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, diarylcycloalkylsulfonium compounds, and aryldicycloalkylsulfonium compounds.
The aryl group of the arylsulfonium compound is preferably an aryl group such as a phenyl group or a naphthyl group, or a heteroaryl group such as an indole residue or a pyrrole residue, and more preferably a phenyl group or an indole residue. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.
The alkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, sec- Examples thereof include a butyl group and a t-butyl group.
The cycloalkyl group that the arylsulfonium compound has as necessary is preferably a cycloalkyl group having 3 to 15 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.
Aryl group, alkyl group of R ₂₀₁ to R _203, cycloalkyl group, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms) , An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group may be substituted. Preferred substituents are straight chain, branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and straight chain, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, and particularly preferably. They are a C1-C4 alkyl group and a C1-C4 alkoxy group. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

Next, the compound (ZI-2) will be described.
Compound (ZI-2) is in the general formula (ZI), R ₂₀₁ ~R ₂₀₃ are each independently a compound when it represents an organic group having no aromatic ring. Here, the aromatic ring includes an aromatic ring having a hetero atom.
The aromatic ring-free organic group as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.
R _{201 to} R ₂₀₃ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear, branched, cyclic 2-oxoalkyl group, an alkoxycarbonylmethyl group, particularly A linear or branched 2-oxoalkyl group is preferred.

The alkyl group as R ₂₀₁ to R ₂₀₃ may be linear, it may be either branched, preferably a straight-chain or branched alkyl group (e.g., methyl group having 1 to 10 carbon atoms, an ethyl group, a propyl Group, butyl group, pentyl group). The alkyl group as R ₂₀₁ to R ₂₀₃ is a straight-chain or branched 2-oxoalkyl group is preferably an alkoxymethyl group.
The cycloalkyl group as R ₂₀₁ to R ₂₀₃ is preferably, and a cycloalkyl group having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, norbornyl). The cycloalkyl group as R ₂₀₁ to R ₂₀₃ is preferably a cyclic 2-oxoalkyl group.
The 2-oxoalkyl group as R _{201 to} R ₂₀₃ may be linear, branched or cyclic, and preferably a group having> C═O at the 2-position of the above alkyl group or cycloalkyl group Can be mentioned.
The alkoxy group in the alkoxycarbonylmethyl group as R ₂₀₁ to R _203, preferably may be mentioned alkoxy groups having 1 to 5 carbon atoms (a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group).
R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

  The compound (ZI-3) is a compound represented by the following general formula (ZI-3), and is a compound having a phenacylsulfonium salt structure.

In general formula (ZI-3),
R _{1c to} R _5c each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group or a halogen atom.
R _6c and R _7c each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group.
Rx and Ry each independently represents an alkyl group, a cycloalkyl group, an allyl group or a vinyl group.
Any two or more of R _1c to R _7c, and R _x and R _y may be bonded to each other to form a ring structure, the ring structure may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond May be included. Examples of the group formed by combining any two or more of R _{1c to} R _7c and R _x and R _y include a butylene group and a pentylene group.
X ^- represents a non-nucleophilic anion, in formula (ZI) in, X ^- are those same as the.

The alkyl group as R _{1c to} R _7c may be linear or branched, for example, an alkyl group having 1 to 20 carbon atoms, preferably a linear or branched alkyl group having 1 to 12 carbon atoms. Examples thereof include a group (for example, methyl group, ethyl group, linear or branched propyl group, linear or branched butyl group, linear or branched pentyl group).
The cycloalkyl group as R _{1c to} R _7c is preferably a cycloalkyl group having 3 to 8 carbon atoms (for example, a cyclopentyl group or a cyclohexyl group).
The alkoxy group as R _{1c to} R _{5c may} be linear, branched or cyclic, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group), C3-C8 cyclic alkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group) ).
Preferably, any one of R _{1c to} R _5c is a linear or branched alkyl group, a cycloalkyl group, or a linear, branched or cyclic alkoxy group, and more preferably the sum of the carbon number of R _{1c to} R _5c is 2 ~ 15. Thereby, solvent solubility improves more and generation | occurrence | production of a particle is suppressed at the time of a preservation | save.

_Examples of the alkyl group as R _x and R _y include the same alkyl groups as R _{1c to} R _7c . The alkyl group as R _x and R _y is more preferably a linear or branched 2-oxoalkyl group or an alkoxycarbonylmethyl group.
_Examples of the cycloalkyl group as R _x and R _y include the same cycloalkyl groups as R _{1c to} R _7c . The cycloalkyl group as R _x and R _y is more preferably a cyclic 2-oxoalkyl group.
Examples of the linear, branched or cyclic 2-oxoalkyl group include a group having> C═O at the 2-position of the alkyl group or cycloalkyl group as R _{1c to} R _7c .
Examples of the alkoxy group in the alkoxycarbonylmethyl group include the same alkoxy groups as R _{1c to} R _5c .
R _x and R _y are preferably an alkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more.

In the general formulas (ZII) and (ZIII),
R ₂₀₄ to R ₂₀₇ each independently represents an optionally substituted aryl group, which may have a substituent alkyl or optionally substituted cycloalkyl group.

Phenyl group and a naphthyl group are preferred as the aryl group of R ₂₀₄ to R _207, more preferably a phenyl group.
The alkyl group as R ₂₀₄ to R ₂₀₇ may be linear, it may be either branched, preferably a straight-chain or branched alkyl group (e.g., methyl group having 1 to 10 carbon atoms, an ethyl group, a propyl Group, butyl group, pentyl group).
The cycloalkyl group as R ₂₀₄ to R ₂₀₇ is preferably, and a cycloalkyl group having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, norbornyl).
The R ₂₀₄ to R ₂₀₇ are substituents which may have, for example, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (e.g., 6 carbon atoms 15), alkoxy groups (for example, having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups and the like.
X ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as X ^{− in} formula (ZI).

  Among the compounds that generate an acid upon irradiation with actinic rays or radiation, compounds represented by the following general formulas (ZIV), (ZV), and (ZVI) can be further exemplified.

In the general formulas (ZIV) to (ZVI),
Ar ₃ and Ar ₄ each independently represent a substituted or unsubstituted aryl group.
R ₂₀₆ represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, or a substituted or unsubstituted aryl group.
R ₂₀₇ and R ₂₀₈ each independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or an electron-withdrawing group.
R ₂₀₇ is preferably a substituted or unsubstituted aryl group.
R ₂₀₈ is preferably an electron-withdrawing group, more preferably a cyano group or a fluoroalkyl group.
A represents a substituted or unsubstituted alkylene group, a substituted or unsubstituted cycloalkylene group, a substituted or unsubstituted alkenylene group, or a substituted or unsubstituted arylene group.

Among the compounds that generate an acid upon irradiation with actinic rays or radiation, more preferred are compounds represented by the general formulas (ZI) to (ZIII), and still more preferred are compounds represented by (ZI). Particularly preferred are compounds represented by (ZI-1) to (ZI-3).
Furthermore, the compound which generate | occur | produces the acid represented by the following general formula (AC1)-(AC3) by irradiation of actinic light or a radiation is preferable.

That is, a particularly preferable embodiment of the component (A) is a compound in which, in the structure of the general formula (ZI), X ⁻ is an anion selected from the general formulas (AN1), (AN3), and (AN4). .

Moreover, it is also one of the preferable aspects to use a diazodisulfone or oxime ester as (A) component.
In addition, as a component (A), it is also one of preferred embodiments to use a sulfonium salt having a bis (alkylsulfonyl) amide anion or a tris (alkylsulfonyl) methide anion.

  Among the compounds that decompose upon irradiation with actinic rays or radiation to generate an acid, examples of particularly preferable compounds are listed below.

An acid generator can be used individually by 1 type or in combination of 2 or more types. When two or more types are used in combination, it is preferable to combine two types of compounds that generate two types of organic acids that differ in the total number of atoms excluding hydrogen atoms by two or more.
The content of the acid generator in the composition is preferably from 0.1 to 20% by mass, more preferably from 0.5 to 10% by mass, and even more preferably from 1 to 20% by mass, based on the total solid content of the positive resist composition. 7% by mass.

Organic Basic Compound In the present invention, it is preferable to use an organic basic compound from the viewpoint of improving performance such as resolution and improving storage stability. As the organic basic compound, a compound containing a nitrogen atom (nitrogen-containing basic compound) is more preferable.
A preferable organic basic compound in the present invention is a compound having a stronger basicity than phenol.
As a preferable chemical environment, the following general formulas (A) to (E) can be exemplified. The general formulas (B) to (E) may be part of a ring structure.

In general formula (A),
R ²⁰⁰ , R ²⁰¹ and R ²⁰² may be the same or different and are a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms. Represents. R ²⁰¹ and R ²⁰² may combine with each other to form a ring.

The alkyl group, cycloalkyl group and aryl group as R ²⁰⁰ , R ²⁰¹ and R ²⁰² may have a substituent. Examples of the alkyl group and cycloalkyl group having a substituent include an aminoalkyl group having 1 to 20 carbon atoms, an aminocycloalkyl group having 3 to 20 carbon atoms, a hydroxyalkyl group having 1 to 20 carbon atoms, and 3 carbon atoms. ~ 20 hydroxycycloalkyl groups are preferred.

In general formula (E),
R ²⁰³ , R ²⁰⁴ , R ²⁰⁵ and R ²⁰⁶ may be the same or different and each represents an alkyl group having 1 to 6 carbon atoms and a cycloalkyl group.

Further preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms of different chemical environments in one molecule, and particularly preferably both a substituted or unsubstituted amino group and a ring structure containing a nitrogen atom. Or a compound having an alkylamino group.

  Preferred examples include guanidine, aminopyridine, aminoalkylpyridine, aminopyrrolidine, indazole, imidazole, pyrazole, pyrazine, pyrimidine, purine, imidazoline, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine and the like. Preferred substituents that these may have include amino groups, alkylamino groups, aminoaryl groups, arylamino groups, alkyl groups (substituent alkyl groups, particularly aminoalkyl groups), alkoxy groups, acyl groups, and acyloxy groups. , Aryl group, aryloxy group, nitro group, hydroxyl group, cyano group and the like.

Particularly preferred compounds include guanidine, 1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, imidazole, 2-methylimidazole, 4-methylimidazole, N-methylimidazole, 2-phenylimidazole, 4 , 5-diphenylimidazole, 2,4,5-triphenylimidazole, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2- (Aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-6-methylpyridine, 3-aminoethylpyridine, 4- Aminoethylpyridine, 3-aminopyrrolidine, Perazine, N- (2-aminoethyl) piperazine, N- (2-aminoethyl) piperidine, 4-amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-aminoethyl) pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1-p-tolylpyrazole, pyrazine, 2- (aminomethyl) -5-methylpyrazine, Examples include, but are not limited to, pyrimidine, 2,4-diaminopyrimidine, 4,6-dihydroxypyrimidine, 2-pyrazoline, 3-pyrazoline, N-aminomorpholine, N- (2-aminoethyl) morpholine. It is not a thing.
These nitrogen-containing basic compounds are used alone or in combination of two or more.

  More preferable compounds include compounds having an imidazole structure, a diazabicyclo structure, a trialkylamine structure or an aniline structure, an alkylamine derivative having a hydroxyl group and / or an ether bond, and an aniline derivative having a hydroxyl group and / or an ether bond. .

Examples of the compound having an imidazole structure include imidazole, 2,4,5-triphenylimidazole, benzimidazole, and 2-phenylbenzimidazole. Examples of the compound having a diazabicyclo structure include 1,4-diazabicyclo [2,2,2] octane, 1,5-diazabicyclo [4,3,0] non-5-ene, and 1,8-diazabicyclo [5,4,0. ] Undecar 7-ene etc. are mentioned. Examples of the compound having a trialkylamine structure include tri (n-butyl) amine, tri (n-octyl) amine, and dicyclohexylmethylamine. Examples of the aniline compound include 2,6-diisopropylaniline, N, N-dimethylaniline, N, N-dibutylaniline, N, N-dihexylaniline and the like. Examples of the alkylamine derivative having a hydroxyl group and / or an ether bond include ethanolamine, diethanolamine, triethanolamine, N-phenyldiethanolamine, and tris (methoxyethoxyethyl) amine. Examples of aniline derivatives having a hydroxyl group and / or an ether bond include N, N-bis (hydroxyethyl) aniline.
These nitrogen-containing basic compounds are used alone or in combination of two or more.

A tetraalkylammonium salt type nitrogen-containing basic compound can also be used.
Among these, tetraalkylammonium hydroxide having 1 to 8 carbon atoms (tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra- (
n-butyl) ammonium hydroxide and the like are preferred.
These nitrogen-containing basic compounds are used alone or in combination of two or more.

  The use ratio of the acid generator and the organic basic compound in the composition is preferably (total amount of acid generator) / (organic basic compound) (molar ratio) = 2.5 to 300. By setting the molar ratio to 2.5 or more, high sensitivity is obtained, and by setting the molar ratio to 300 or less, it is possible to suppress the resist pattern from becoming thicker over time until post-exposure heat treatment and improve resolution. . (Total amount of acid generator) / (organic basic compound) (molar ratio) is preferably 5.0 to 200, more preferably 7.0 to 150.

Surfactant In the present invention, a surfactant can be used, which is preferable from the viewpoints of film forming properties, pattern adhesion, development defect reduction, and the like.

Specific examples of the surfactant include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, polyoxyethylene Polyoxyethylene alkyl allyl ethers such as nonylphenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate Sorbitan fatty acid esters such as rate, polyoxyethylene sorbitan monolaurate, polyoxyethylene Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as bitane monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate, Ftop EF301, EF303, EF352 (manufactured by Shin-Akita Kasei Co., Ltd.), Megafac F171, F173 (manufactured by Dainippon Ink and Chemicals), Florad FC430, FC431 (manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), Troysol S-366 (manufactured by Troy Chemical Co., Ltd.), etc. Hexane polymer KP341 (manufactured by Shin-Etsu Chemical Co.) and acrylic or methacrylic acid-based (co) polymer Polyflow No. 75, no. 95 (manufactured by Kyoeisha Yushi Chemical Co., Ltd.).
The compounding amount of these surfactants is usually 2 parts by mass or less, preferably 1 part by mass or less per 100 parts by mass of the solid content in the positive resist composition of the present invention.
These surfactants may be added alone or in some combination.

The surfactant is any one of fluorine and / or silicon surfactants (fluorine surfactants and silicon surfactants, surfactants containing both fluorine atoms and silicon atoms), or It is preferable to contain 2 or more types.
As these surfactants, for example, JP-A-62-36663, JP-A-61-226746, JP-A-61-226745, JP-A-62-170950, JP-A-63-34540 No. 7, JP-A-7-230165, JP-A-8-62834, JP-A-9-54432, JP-A-9-5988, JP-A 2002-277862, US Pat. No. 5,405,720. No. 5,360,692, No. 5,529,881, No. 5,296,330, No. 5,543,098, No. 5,576,143, No. 5,294,511, No. 5,824,451. The following commercially available surfactants can also be used as they are.
Examples of commercially available surfactants that can be used include F-top EF301, EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430, 431 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176, F189, R08 (Dainippon Ink Chemical Co., Ltd.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.), Troisol S-366 (Troy Chemical Co., Ltd.), etc. Fluorine type surfactant or silicon type surfactant can be mentioned. Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

In addition to the known surfactants described above, the surfactant is derived from a fluoroaliphatic compound produced by a telomerization method (also called telomer method) or an oligomerization method (also called oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.
As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. Or may be block copolymerized. Examples of the poly (oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group, a poly (oxybutylene) group, and the like, and a poly (oxyethylene, oxypropylene, and oxyethylene group). A unit having different chain lengths in the same chain length, such as a block linked body) or a poly (block linked body of oxyethylene and oxypropylene) group, may be used. Furthermore, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer but also a monomer having two or more different fluoroaliphatic groups, Further, it may be a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different (poly (oxyalkylene)) acrylates (or methacrylates).
Examples of commercially available surfactants include Megafac F178, F-470, F-473, F-475, F-476, and F-472 (Dainippon Ink Chemical Co., Ltd.). Further, a copolymer of an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxy) (Ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate) copolymer, acrylate (or methacrylate) and (poly (oxyalkylene)) acrylate having C ₈ F ₁₇ groups (or Copolymer of acrylate (or methacrylate), (poly (oxyethylene)) acrylate (or methacrylate), and (poly (oxypropylene)) acrylate (or methacrylate) having a C ₈ F ₁₇ group Coalesce, etc. Can.

  The amount of the surfactant used is preferably 0.0001 to 2% by mass, more preferably 0.001 to 1% by mass, based on the total amount of the positive resist composition (excluding the solvent).

Other Components The positive resist composition of the present invention can further contain a dye, a photobase generator and the like, if necessary.

1. Dye A dye can be used in the present invention.
Suitable dyes include oily dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 603, Oil Black BY, Oil Black BS, Oil Black T-505 (oriental chemical industry) Co., Ltd.), crystal violet (CI42555), methyl violet (CI42535), rhodamine B (CI45170B), malachite green (CI42000), methylene blue (CI522015) and the like.

2. Photobase generator As photobase generators that can be added to the composition of the present invention, JP-A-4-151156, JP-A-4-162040, JP-A-5-197148, JP-A-5-5995, JP-A-6-194835, Examples thereof include compounds described in JP-A-8-146608, JP-A-10-83079 and European Patent No. 622682, specifically, 2-nitrobenzylcarbamate, 2,5-dinitrobenzylcyclohexylcarbamate, N-cyclohexyl-4- Methylphenylsulfonamide, 1,1-dimethyl-2-phenylethyl-N-isopropylcarbamate and the like can be suitably used. These photobase generators are added for the purpose of improving the resist shape and the like.

3. Solvent The positive resist composition of the present invention is dissolved in a solvent that dissolves each of the above components and coated on a support. The solid content concentration of all resist components is usually preferably 2 to 30% by mass, more preferably 3 to 25% by mass.
Solvents used here include ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl ether acetate , Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N-dimethyl Formamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran and the like are preferable. Or mixed to use.

  The positive resist composition of the present invention is applied onto a substrate to form a thin film. The thickness of this coating film is preferably 0.05 to 4.0 μm.

When the positive resist composition of the present invention is directly coated on a substrate having a highly reflective surface without coating an antireflection film, the generation of standing waves is remarkably suppressed and a good pattern can be obtained. However, even if an antireflection film is used, a good pattern can be formed. As the antireflection film used as the lower layer of the resist, either an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, amorphous silicon, or an organic film type made of a light absorber and a polymer material may be used. it can. The former requires equipment such as a vacuum deposition apparatus, a CVD apparatus, and a sputtering apparatus for film formation. Examples of the organic antireflection film include a condensate of a diphenylamine derivative and a formaldehyde-modified melamine resin described in Japanese Patent Publication No. 7-69611, an alkali-soluble resin, and a light absorber, and an anhydrous maleate described in US Pat. No. 5,294,680. A reaction product of an acid copolymer and a diamine type light absorbent, a resin binder described in JP-A-6-188631, and a methylolmelamine thermal crosslinking agent, a carboxylic acid group and an epoxy described in JP-A-6-118656 An acrylic resin type antireflection film having a group and a light-absorbing group in the same molecule, composed of a methylol melamine and a benzophenone-based light-absorbing agent described in JP-A-8-87115, and a polyvinyl alcohol resin described in JP-A-8-179509. The thing etc. which added the molecular light absorber are mentioned.
In addition, as the organic antireflection film, commercially available organic antireflection films such as DUV30 series, DUV-40 series manufactured by Brewer Science, AR-2, AR-3, AR-5 manufactured by Shipley, etc. may be used. it can.

  In the manufacture of precision integrated circuit elements, the pattern forming process on the resist film is carried out on the substrate (eg, silicon / silicon dioxide coated substrate, glass substrate, ITO substrate, quartz / chromium oxide coated substrate, etc.). A resist pattern is formed by applying a resist composition, forming a resist film, and then irradiating actinic rays or radiation such as KrF excimer laser light, electron beam, EUV light, etc., heating, developing, rinsing and drying. Can be formed.

Examples of the alkaline developer used in development include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, and primary amines such as ethylamine and n-propylamine. Secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcoholamines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, An aqueous solution (usually 0.1 to 20% by mass) of an alkali such as a quaternary ammonium salt such as choline or a cyclic amine such as pyrrole or piperidine can be used. Furthermore, an appropriate amount of an alcohol such as isopropyl alcohol or a nonionic surfactant may be added to the alkaline aqueous solution.
Among these developers, quaternary ammonium salts are preferable, and tetramethylammonium hydroxide and choline are more preferable.
The pH of the alkaline developer is usually 10-15.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, the content of this invention is not limited by this. Examples 13 and 14 are to be read as reference examples.

Synthesis Example 1 (Synthesis of Resin (B-17))
A copolymer of p-hydroxystyrene and t-butyl methacrylate (molar composition ratio 80/20) 35.0 g and propylene glycol monomethyl ether acetate (PGMEA) (400 g) were dissolved in a flask, distilled under reduced pressure, PGMEA was distilled off azeotropically. After confirming that the water content was sufficiently low, triethylamine (5.0 g) was added. Subsequently, a solution in which 5.0 g of 2-naphthoyl chloride was dissolved in 50 g of acetone was added over 20 minutes, and then reacted with stirring for 60 minutes. Water (400 ml) and ethyl acetate (800 ml) were added, separated, washed with water, and then ethyl acetate, water and azeotropic PGMEA were distilled off by distillation under reduced pressure, and the resin having the substituent according to the present invention. (B-17) (molar composition ratio 10/70/20, molecular weight 13000, dispersity 1.7, 30% PGMEA solution) was obtained.

  In the same manner, resins shown in Table 1 below were synthesized.

  Hereinafter, the structure of the resin (BC) is shown.

Examples 1 to 19 and Comparative Example 1
PGMEA (propylene glycol monomethyl ether acetate) / PGME (propylene glycol monomethyl ether) (=) at a blending ratio (addition amount) described in Table 2 so that the concentration is 10% by mass. 8/2 mass ratio) was dissolved in a mixed solvent and filtered through a microfilter having a pore diameter of 0.1 μm to prepare positive resist solutions of Examples 1 to 19 and Comparative Example 1.
The obtained positive resist solution was applied onto a bare silicon substrate using a spin coater (Mark 8 manufactured by Tokyo Electron Ltd.) and dried at 90 ° C. for 90 seconds to form 410 μm resist films. Then, it exposed with the KrF excimer laser (Canon company FPA-3000EX5 of wavelength 248nm, NA = 0.60, (sigma) = 0.75). After the exposure, the substrate was heated on a 100 ° C. hot plate for 60 seconds, immediately immersed in a 0.26N tetramethylammonium hydroxide (TMAH) aqueous solution for 60 seconds, rinsed with water for 30 seconds and dried. The pattern on the silicon wafer thus obtained was observed with a scanning electron microscope to evaluate the performance of the resist.

[Resolving power]: Represents the limiting resolving power at an exposure amount for reproducing a 0.30 μm line and space (1: 1) mask pattern.
[Residual standing wave]: The side wall of the resist pattern obtained with a 0.30 μm line-and-space (1: 1) mask pattern was observed with a scanning electron microscope, and the following four-level evaluation was performed.
◯: When there is no standing wave and the pattern side wall is clean △: When the standing wave is slightly seen or unevenness is seen on the pattern side wall ×: When standing wave can be clearly confirmed XX: Standing When a wave can be confirmed very strongly [Dense / Dense Bias]: A line-and-space (1: 1) mask pattern of 0.30 μm at the line width of the limiting resolution of the line-and-space pattern (dense pattern (1: 1)) When the 10% exposure amount was increased and the 10% exposure amount was decreased with reference to the exposure amount to be reproduced, the absolute value (δx) of the difference between the line widths obtained was obtained. The same exposure was performed for the isolated line pattern (sparse pattern (1: 5)), and the absolute value (δy) of the line width difference was obtained. The absolute value of the difference between δx and δy was used as a criterion for evaluating the density bias. The smaller this value, the better the density bias.

[Development Defect]: Each resist film was applied to a thickness of 0.5 μm on a 6-inch Bare Si substrate and dried on a vacuum adsorption hot plate at 130 ° C. for 60 seconds. Next, after exposure with a Nikon stepper NSR-1505EX through a test mask having a 0.35 μm contact hole pattern (Hole Duty ratio = 1: 3), post-exposure heating was performed at 130 ° C. for 90 seconds. Subsequently, the paddle development was performed with 2.38% TMAH (tetramethylammonium hydroxide aqueous solution) for 60 seconds, followed by washing with pure water for 30 seconds and spin drying. The number of development defects (development defects due to KLA) of the samples thus obtained was measured by a KLA-Tencor KLA-2112 machine, and the obtained primary data value was defined as the number of development defects.
The evaluation results are shown in Table 2.

Hereinafter, abbreviations in the table are shown.
[Basic compounds]
D-1: Tetrabutylammonium hydroxide D-2: Dicyclohexylmethylamine D-3: Tris (methoxyethoxyethylamine)
[Surfactant]
W-1: Fluorosurfactant, MegaFuck F-176 (Dainippon Ink Chemical Co., Ltd.)
W-2: Fluorine / silicone surfactant, MegaFac R08 (manufactured by Dainippon Ink & Chemicals, Inc.)

  From Table 2, it is clear that the positive resist composition of the present invention has high resolution, good density dependence, and reduced development defects and standing waves.

Claims (7)

It has a repeating unit represented by the following general formula (Ia) or (Ib), and further has a repeating unit represented by the following general formula (II). A positive resist composition comprising an increasing resin (B) and a compound (A) that generates an acid upon irradiation with actinic rays or radiation.

In general formula (Ia):
X represents a hydrogen atom, a methyl group or a halogen atom.
Q ₁ represents an arylcarbonyl group. When n is 2 to 3, the plurality of Q ₁ may be the same or different.
L represents a monovalent organic group, a halogen atom, a cyano group, or a nitro group. When m is 2, two Ls may be the same or different.
n represents an integer of 1 to 3.
m represents an integer of 0 to 2.
In general formula (Ib):
X represents a hydrogen atom, a methyl group or a halogen atom.
Q ₂ represents an arylcarbonyl group.
Z ₂ represents a divalent linking group.

In general formula (II):
Y represents a hydrogen atom, a methyl group, a halogen atom, a cyano group, a hydroxymethyl group, an alkoxymethyl group or an acyloxymethyl group.
A represents a group capable of leaving by the action of an acid.
However, from the resin (B), only the repeating unit represented by the following general formula (1), the repeating unit represented by the following general formula (2), and the repeating unit represented by the following general formula (3) The resin consisting of is excluded.

In general formula (1),
R ₁ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom, or a perfluoroalkyl group having 1 to 4 carbon atoms.
R ₂ and R ₃ each independently represents an alkyl group.
X represents an alicyclic group.
In general formula (2),
R ₄ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom, or a perfluoroalkyl group having 1 to 4 carbon atoms.
R ₅ represents an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group.
l represents an integer of 0 to 4.
In general formula (3),
R ₆ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom, or a perfluoro having 1 to 4 carbon atoms.
Represents a loalkyl group.
R ₇ represents an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group.
R ₈ represents an aryl group.
m represents an integer of 0 to 4.
n represents an integer of 1 to 5. The positive resist composition according to claim 1, wherein the resin (B) further has a repeating unit represented by the following general formula (III).

In general formula (III):
X represents a hydrogen atom, a methyl group or a halogen atom.
R represents a hydrogen atom or a group capable of leaving by the action of an acid.
L represents a monovalent organic group, a halogen atom, a cyano group, or a nitro group.
n represents an integer of 1 to 3.
m represents an integer of 0 to 2. Resin (B), The positive resist composition according to claim 1 or 2 characterized by having a repeating unit represented by the following general formula (IV).

In general formula (IV),
R ₁ represents a hydrogen atom, an alkyl group, a cyano group or a halogen atom.
R ₃ represents a monovalent organic group that does not have decomposability due to the action of an acid, a halogen atom, or a nitro group.
p represents an integer of 0 to 5. When p is 2 or more, the plurality of R ₃ may be different from each other. Actinic rays or radiation a compound capable of generating an acid upon irradiation (A) The positive resist composition according to any one of claims 1 to 3, characterized in that a diazodisulfone or oxime ester. Actinic rays or radiation a compound capable of generating an acid upon irradiation with (A) is any one of claims 1-3, characterized in that the bis (alkylsulfonyl) amide anion or tris sulfonium salt having a (alkylsulfonyl) methide anion The positive resist composition as described in 1. above.   A resist film formed from the positive resist composition according to claim 1. A pattern forming method comprising: exposing and developing the resist film according to claim 6 .