JP2010134279A - Actinic ray-sensitive or radiation-sensitive resin composition and pattering method using the composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positive resist composition which ensures good LWR and MEEF and a pattering method using the positive resist composition. <P>SOLUTION: The actinic ray-sensitive or radiation-sensitive resin composition is provided including (A) at least one compound which generates an acid represented by general formula (0) upon irradiation with actinic rays or radiation and (B) a resin which exhibits increased solubility in an alkali developer under the action of an acid, wherein R<SB>1</SB>represents an organic group, R<SB>2</SB>represents H or an organic group, R<SB>1</SB>and R<SB>2</SB>are bonded to each other to form a monocyclic or polycyclic structure, A represents a group which decomposes under the action of an acid or base, and n represents 1 or 2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an actinic ray- or radiation-sensitive resin composition whose properties change upon reaction with actinic ray or radiation, and a pattern forming method using the composition. More specifically, a positive resist composition used in a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal or a thermal head, other photofabrication processes, a lithographic printing plate, an acid curable composition, and The present invention relates to a pattern forming method using the positive resist composition.

  In the present invention, “active light” or “radiation” means, for example, an emission line spectrum of a mercury lamp, far ultraviolet rays represented by an excimer laser, X-rays, electron beams, and the like. In the present invention, light means actinic rays or radiation.

  The chemically amplified resist composition generates an acid in the exposed area by irradiation with actinic rays or radiation such as far ultraviolet light, and a reaction solution using the acid as a catalyst to develop a developing solution for the irradiated and non-irradiated areas of the active light or radiation It is a pattern forming material that changes the solubility in the substrate and forms a pattern on the substrate.

As the acid generator, those that generate perfluoroalkanesulfonic acid such as triphenylsulfonium triflate and bis (t-butylphenyl) iodonium perfluorobutanesulfonate are well known. In general, perfluoroalkyl compounds have high hydrophobicity, and have problems such as poor developability and development residue (scum). On the other hand, Patent Document 1 proposes a photoacid generator having a low fluorine content, but there is a problem that LWR and MEEF are incompatible. Moreover, although the photoacid generator which has the group decomposed | disassembled by an acid is illustrated in patent document 2, it has three or more fluorine in 1 molecule, and was not satisfactory from a viewpoint of developability or LWR. .
Japanese Patent No. 4150509 JP 2007-196992 A

  An object of the present invention is to provide a positive resist composition having good LWR and MEEF, and a pattern forming method using the positive resist composition. Another object of the present invention is to provide a positive resist composition having sufficient sensitivity and resolution not only in ArF exposure but also in EUV exposure, and a pattern forming method using the positive resist composition. .

As a result of intensive studies to solve the above problems, the present inventor has reached the present invention shown below.
(1) (A) At least one compound that generates an acid represented by the following general formula (0) upon irradiation with actinic rays or radiation, and (B) a resin whose solubility in an alkaline developer is increased by the action of the acid. An actinic ray-sensitive or radiation-sensitive resin composition comprising:

In general formula (0),
R ₁ represents an organic group.

R ₂ represents a hydrogen atom or an organic group. R ₁ and R ₂ may combine to form a monocyclic or polycyclic structure.

  A represents a group that decomposes by the action of an acid or a base.

  n represents 1 or 2.

(2) In the general formula (0), R ₁ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted group having an oxygen atom, a sulfur atom or a nitrogen atom in the alkyl chain, a substituted or unsubstituted cyclo An alkyl group, a substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted aryl group, wherein R ₂ is a hydrogen atom, a substituted or unsubstituted alkyl group, substituted or unsubstituted A group having an oxygen atom, sulfur atom or nitrogen atom in the alkyl chain, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted group. The actinic ray-sensitive or radiation-sensitive resin composition according to (1), which is an aryl group.

(3) The compound (A) that generates an acid represented by the general formula (0) by irradiation with actinic rays or radiation is a compound represented by the following general formula (I), (1 ) Or the actinic ray-sensitive or radiation-sensitive resin composition according to (2).

In the general formula (I), M ^{m +} represents an organic counter cation, and m represents an integer. R ₁ , R ₂ , A and n have the same meanings as R ₁ , R ₂ and A in the general formula (0), respectively.

  (4) A pattern comprising a step of forming a film using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of (1) to (3), and exposing and developing the film. Forming method.

(5) A compound that generates an acid represented by the following general formula (0) upon irradiation with actinic rays or radiation.

In general formula (0),
R ₁ represents an organic group.
R ₂ represents a hydrogen atom or an organic group. R ₁ and R ₂ may combine to form a monocyclic or polycyclic structure.
A represents a group that decomposes by the action of an acid or a base.
n represents 1 or 2.
(6) In the general formula (0), R ₁ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted group having an oxygen atom, a sulfur atom or a nitrogen atom in the alkyl chain, a substituted or unsubstituted cyclo An alkyl group, a substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted aryl group, wherein R ₂ is a hydrogen atom, a substituted or unsubstituted alkyl group, substituted or unsubstituted A group having an oxygen atom, sulfur atom or nitrogen atom in the alkyl chain, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted group. The compound according to (5), which is an aryl group.

(7) The compound that generates an acid represented by the general formula (0) by irradiation with actinic rays or radiation is a compound represented by the following general formula (I), (5) or The compound as described in (6).

In the general formula (I), M ^{m +} represents an organic counter cation, and m represents an integer. R ₁ , R ₂ , A and n have the same meanings as R ₁ , R ₂ and A in the general formula (0), respectively.
(8) A photoacid generator comprising the compound according to any one of (5) to (7).
(9) A compound represented by the following general formula (II):

In general formula (II):
R ₁ represents an organic group.
R ₂ represents a hydrogen atom or an organic group. R ₁ and R ₂ may combine to form a monocyclic or polycyclic structure.
A represents a group that decomposes by the action of an acid or a base.
n represents 1 or 2.
M ′ ⁺ represents a monovalent metal cation.

(10) In the general formula (II), R ₁ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted group having an oxygen atom, a sulfur atom or a nitrogen atom in the alkyl chain, a substituted or unsubstituted cyclo An alkyl group, a substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted aryl group, wherein R ₂ is a hydrogen atom, a substituted or unsubstituted alkyl group, substituted or unsubstituted A group having an oxygen atom, sulfur atom or nitrogen atom in the alkyl chain, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted group. The compound according to (9), which is an aryl group.

  According to the present invention, it is possible to provide a positive resist composition excellent in both LWR and MEEF. Further, according to the present invention, it is possible to provide a positive resist composition having sufficient sensitivity and resolution not only in ArF exposure but also in EUV exposure.

The treatment agent of the present invention will be described in detail below.
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 does not have a substituent and what has 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).

[(A) Photoacid generator]
The compound provided by the present invention is a compound that generates an acid represented by the general formula (0) upon irradiation with actinic rays or radiation, and can be used in a positive photosensitive composition as a photoacid generator. Hereinafter, compounds that generate an acid represented by the general formula (0) are referred to as “photoacid generator (A)”, “compound (A)”, and the like.

In general formula (0),
R ₁ represents an organic group.
R ₂ represents a hydrogen atom or an organic group. R ₁ and R ₂ may combine to form a monocyclic or polycyclic structure.
A represents a group that decomposes by the action of an acid or a base.
n represents 1 or 2.
Hereinafter, the general formula (0) will be described in detail.

R ₁ represents an organic group. Examples of the organic group include an alkyl group, a cycloalkyl group, and an aryl group.

R ₂ represents a hydrogen atom or an organic group. Examples of the organic group include an alkyl group, a cycloalkyl group, and an aryl group.

The alkyl group as R ₁ and R ₂ may have a substituent, and is preferably a linear or branched alkyl group having 1 to 30 carbon atoms, and an oxygen atom, a sulfur atom, a nitrogen atom in the alkyl chain You may have. Specifically, methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-octyl group, n-dodecyl group, n-tetradecyl group, n-octadecyl group, etc. And a branched alkyl group such as isopropyl group, isopropyl group, isobutyl group, t-butyl group, neopentyl group, 2-ethylhexyl group. Preferably, they are a methyl group, an ethyl group, and an n-propyl group.

  Examples of the substituent that the alkyl group may have include an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom), an acyl group, an acyloxy group, a cyano group, a hydroxyl group, and a carboxy group. , Alkoxycarbonyl group, nitro group and the like.

The cycloalkyl group as R ₁ and R ₂ may have a substituent, preferably a cycloalkyl group having 3 to 20 carbon atoms, which may be monocyclic or polycyclic, and has an oxygen atom in the ring. You may have. Preferably, a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, an adamantyl group, etc. can be mentioned. Particularly preferred is cyclohexyl. Examples of the substituent that the cycloalkyl group may have include the same groups as the above-described substituents that the alkyl group as R ₁ and R ₂ may have.

The aryl group as R ₁ and R ₂ may have a substituent, preferably an aryl group having 6 to 14 carbon atoms, and preferably a phenyl group, a naphthyl group, and the like. Examples of the substituent that the aryl group may have include the same groups as the above-described substituents that the alkyl group as R ₁ and R ₂ may have.

R ₁ and R ₂ may combine to form a monocyclic or polycyclic ring structure. A preferable cyclic structure is a cyclic structure having 4 to 15 carbon atoms, which may have an oxygen atom, a sulfur atom or a nitrogen atom in the carbon chain, and may have a substituent. Particularly preferred are piperidinyl group, pyrrolidinyl group, azacyclooctyl group and decahydroquinolyl group.

A represents a group that decomposes by the action of an acid or a base.
As the group (A) that decomposes by the action of an acid, for example, a specific structure is shown below.

Formula (a), an _{R 1} in (b), in (c), _{R 1} is the general formula (I).
R ′ ₁ and R ′ ₂ each independently represents an alkyl group, a cycloalkyl group, or an aryl group. The alkyl group, the cycloalkyl group, and the aryl group have the same meanings as the groups represented by R ₁ described above.

R ′ ₁ and R ′ ₂ may combine to form a monocyclic or polycyclic ring structure. A preferable cyclic structure is a cyclic structure having 4 to 15 carbon atoms, which may have an oxygen atom, a sulfur atom or a nitrogen atom in the carbon chain, and may have a substituent. The structure shown below is preferable.

Wherein, _{R 1} is _{R 1} in the general formula (I). n ₀ is an integer of 0-4. n ₁ is an integer of 1 to 14. Rb ₁ is an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 1 to 8 carbon atoms, a carboxyl group, a halogen atom, a hydroxyl group, cyano Group, acid-decomposable group and the like. More preferably, they are a C1-C4 alkyl group and a halogen atom. A plurality of Rb ₁ may combine to form a ring.

Particularly preferred are the structures shown below. Moreover, you may have a substituent in the following structure.

R ′ ₃ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an aryl group or an aryloxy group. R ′ ₄ represents an alkyl group, a cycloalkyl group, or an aryl group. The alkyl group, the cycloalkyl group, and the aryl group have the same meanings as the groups represented by R ₁ described above.

R ′ ₃ and R ′ ₄ may combine to form a monocyclic or polycyclic ring structure. Preferred cyclic structures include cyclic structures having 4 to 15 carbon atoms, oxygen atoms in the carbon chain, It may have a sulfur atom or a nitrogen atom, and may have a substituent. Particularly preferred is a monocyclic structure having 4 to 6 carbon atoms which may have an oxygen atom or a sulfur atom in the carbon chain, and further may have a substituent, more preferably a tetrahydrofuranyl group, 1 , 4 dioxane 2-yl ether, tetrahydropyranyl ether, tetrahydrothiopyranyl ether.

R ′ _{5 to} R ′ ₇ each independently represents an alkyl group or a cycloalkyl group. The alkyl group, the cycloalkyl group, and the groups represented by R ₁ described above have the same meaning.

R ′ ₅ and R ′ ₆ may be bonded to form a monocyclic or polycyclic structure. Preferred cyclic structures include cyclopentyl, cyclohexyl, norbornyl, and adamantyl, with cyclohexyl being particularly preferred.

Examples of the group (A) that is decomposed by the action of a base include a lactone structure. Any lactone group can be used as long as it has a lactone structure, but it is preferably a 5- to 6-membered ring lactone structure, and forms a bicyclo structure or a spiro structure in the 5- to 6-membered ring lactone structure. And other ring structures may be condensed. It is more preferable to have a repeating unit having a lactone structure represented by any of the following general formulas (LC1-1) to (LC1-15), particularly preferably LC1-1), (LC1-4), (LC1 -5), (LC1-6), (LC1-13), and (LC1-14).

The lactone structure moiety may or may not have a substituent (Rb ₂ ). Preferred substituents (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 1 to 8 carbon atoms, and a carboxyl group. , Halogen atom, hydroxyl group, cyano group, acid-decomposable group and the like. More preferably, they are a C1-C4 alkyl group, a cyano group, and an acid-decomposable group. n ₂ represents an integer of 0-4.

  Preferred A is a group that decomposes by the action of an acid from the viewpoint of the magnitude of volume change. By decomposing by the action of an acid and reducing the volume, it becomes possible to increase the diffusibility of only the exposed part, and there is an effect of achieving both MEEF and LWR improvement.

Examples of the acid represented by the general formula (0) of the present invention include the following specific examples.

The compound (A) of the present invention that generates an acid represented by the general formula (0) is preferably a salt represented by the following general formula (I).

In the general formula _(I), R _{1, R} 2, A and n are each the same meaning as _{R 1, R} 2, A and n in the general formula (0).

M ^{m +} represents an organic counter cation, and m represents an integer. The preferred range of m is 1 or 2, more preferably 1.

Examples of the monovalent organic counter cation represented by M ⁺ include a monovalent onium cation. Examples of the monovalent onium cation may include onium cations such as S, Se, N, P, As, Sb, Cl, Br, and I. Of these onium cations, S and I onium cations are preferred.

In the general formula (I), examples of the M ⁺ monovalent onium cation include those represented by the following general formula (zi) or the following general formula (zii).

In the general formula (zi), R ₃ , R ₄ and R ₅ each independently represents an organic group. Carbon number of the organic group as R < ₃ >, R < ₄ > and R < ₅ > is generally 1-30, preferably 1-20. Two of R ₃ , R ₄ and R ₅ 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. Examples of the group formed by combining two of R ₃ , R ₄ and R include an alkylene group (eg, butylene group, pentylene group). Examples of the organic group as R _3, R ₄ and R _5, for example, corresponding groups in the compounds (zi-1), can be exemplified corresponding groups in (zi-2), (zi -3).

The compound (zi-1) is an arylsulfonium compound in which at least one of R _{3 to} R _{5 in} the general formula (zi) is an aryl group, that is, a compound having arylsulfonium as a cation.

  All of the arylsulfonium compounds may be aryl groups, or some of them may be aryl groups and the rest may be alkyl groups or cycloalkyl groups. 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 a phenyl group or a naphthyl group, and more preferably a phenyl group. The aryl group may be an aryl group having a heterocyclic structure having an oxygen atom, a nitrogen atom, a sulfur atom or the like. Examples of the aryl group having a heterocyclic structure include a pyrrole residue (a group formed by losing one hydrogen atom from pyrrole) and a furan residue (a group formed by losing one hydrogen atom from furan). Groups), thiophene residues (groups formed by the loss of one hydrogen atom from thiophene), indole residues (groups formed by the loss of one hydrogen atom from indole), benzofuran residues ( A group formed by losing one hydrogen atom from benzofuran), a benzothiophene residue (a group formed by losing one hydrogen atom from benzothiophene), and the like. 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 or cycloalkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms and a cycloalkyl group having 3 to 15 carbon atoms, such as a methyl group, Examples thereof include an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.

The aryl group, alkyl group, and cycloalkyl group of R _{3 to} R ₅ are 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 linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, more preferably carbon. These are an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms. Further, when R _{3 to} R ₅ are aryl groups, 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 a compound in which R _{3 to} R ₅ in formula (zi) each independently represents an organic group having no aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.

R _{3 to} R ₅ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear or branched 2-oxoalkyl group, 2-oxocycloalkyl group, alkoxy group. A carbonylmethyl group, particularly preferably a linear or branched 2-oxoalkyl group.

As the alkyl group and cycloalkyl group represented by R _{3 to} R ₅ , a linear or branched alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group), carbon Examples thereof include cycloalkyl groups of several 3 to 10 (cyclopentyl group, cyclohexyl group, norbornyl group). More preferred examples of the alkyl group include a 2-oxoalkyl group and an alkoxycarbonylmethyl group. More preferred examples of the cycloalkyl group include a 2-oxocycloalkyl group.

  The 2-oxoalkyl group may be either linear or branched, and a group having> C = O at the 2-position of the above alkyl group is preferable.

The 2-oxocycloalkyl group is preferably a group having> C═O at the 2-position of the above cycloalkyl group. The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkoxy group having 1 to 5 carbon atoms (methoxy group). Ethoxy group, propoxy group, butoxy group, pentoxy group).

R _{3 to} R ₅ 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.

R _x and R _y independently represents an alkyl group, a cycloalkyl group, an allyl group or a vinyl group.

Any two or more of R _{1c to} R _5c , R _6c and R _7c , and R _x and R _y may be bonded to each other to form a ring structure, and this ring structure includes an oxygen atom and a sulfur atom. , An ester bond and an amide bond may be included. Examples of the group formed by combining any two or more of R _{1c to} R _5c , R _6c and R _7c , and R _x and R _y include a butylene group and a pentylene group.

Zc ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as Z ⁻ in the general formula (zi).

A C3-C8 cyclic alkoxy group (for example, a cyclopentyloxy group, a cyclohexyloxy group) can be mentioned.

Preferably, any 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 and cycloalkyl group as R _x and R _y include the same alkyl group and cycloalkyl group as in R _{1c to} R _7c , such as a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxy group. A carbonylmethyl group is more preferred.

Examples of the 2-oxoalkyl group and 2-oxocycloalkyl 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 in R _{1c to} R _5c .

R _x and R _y are preferably an alkyl group or cycloalkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more alkyl groups or cycloalkyl groups.

In general formula (zii), R ₆ and R ₇ each independently represents an aryl group, an alkyl group, or a cycloalkyl group. The description of the aryl group, the alkyl group, the cycloalkyl group, and the substituent is the same as the description of the aryl group in the compound (zi-1).

Examples of monovalent onium cations represented by preferable M ⁺ are shown below.

Examples of preferred general formula (I) are shown below.

The compound (A) represented by the general formula (I) can be obtained by adding an amine to an ester to form an amide bond to obtain the general formula (II), and further represented by the following general formula (II) It can be obtained by salt exchange of the compound with a cation.

In formula _(II), R _{1, R} 2, A and n are each the same meaning as _{R 1, R} 2, A and n in the general formula (I).
M ′ ⁺ represents a monovalent metal cation, and specific examples thereof include a sodium cation, a potassium cation, and a lithium cation.

  In the positive resist composition of the present invention, the photoacid generator (A) can be used singly or in combination of two or more, and the content thereof is preferably a positive resist composition. The total solid content is 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, and still more preferably 1 to 7% by mass.

  Further, (A) a photoacid generator and a photoacid generator other than the compound may be used in combination. Below, other photo-acid generators other than a photo-acid generator (A) are demonstrated.

[Other photoacid generators]
In the present invention, in addition to the photoacid generator (A) of the present invention, a compound that decomposes upon irradiation with actinic rays or radiation to generate an acid may be used in combination. The amount of the photoacid generator that can be used in combination with the component (A) of the present invention is usually 100/0 to 20 / in molar ratio (photoacid generator (A) / other photoacid generator of the present invention). 80, preferably 100/0 to 40/60, more preferably 100/0 to 50/50. As such photoacid generators that can be used in combination, they are used in photocationic photoinitiators, photoinitiators of radical photopolymerization, photodecolorants of dyes, photochromic agents, or microresists. Known compounds that generate acids upon irradiation with actinic rays or radiation and mixtures 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, such as US Pat. No. 3,849,137, German Patent No. No. 3914407, JP-A 63-26653, JP-A 55-164824, JP-A 62-69263, JP-A 63-146038, JP-A 63-163452, The compounds described in JP-A-62-153853 and 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, etc. can also be used.
Preferred compounds among the acid generators include compounds represented by the following general formulas (ZI), (ZII), and (ZIII).

In the general formula (ZI),
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
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).
Z ⁻ represents a non-nucleophilic anion.

Examples of the non-nucleophilic anion as Z ⁻ include a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methyl anion.

  A non-nucleophilic anion is an anion that has an extremely low ability to cause a nucleophilic reaction, and is an anion that can suppress degradation over time due to an intramolecular nucleophilic reaction. This improves the temporal stability of the resist.

Examples of the sulfonate anion include an aliphatic sulfonate anion, an aromatic sulfonate anion, and a camphor sulfonate anion.
Examples of the carboxylate anion include an aliphatic carboxylate anion, an aromatic carboxylate anion, and an aralkylcarboxylate anion.

  The aliphatic moiety in the aliphatic sulfonate anion may be an alkyl group or a cycloalkyl group, preferably an alkyl group having 1 to 30 carbon atoms and a cycloalkyl group having 3 to 30 carbon atoms such as methyl. Group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group , Tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, adamantyl group, norbornyl group, bornyl group and the like.

  The aromatic group in the aromatic sulfonate anion is preferably an aryl group having 6 to 14 carbon atoms, such as a phenyl group, a tolyl group, and a naphthyl group.

  The alkyl group, cycloalkyl group and aryl group in the aliphatic sulfonate anion and aromatic sulfonate anion may have a substituent. Examples of the substituent of the alkyl group, cycloalkyl group, and aryl group in the aliphatic sulfonate anion and aromatic sulfonate anion include, for example, a nitro group, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), carboxyl group , Hydroxyl group, amino group, cyano group, alkoxy group (preferably having 1 to 15 carbon atoms), cycloalkyl group (preferably having 3 to 15 carbon atoms), aryl group (preferably having 6 to 14 carbon atoms), alkoxycarbonyl group ( Preferably 2 to 7 carbon atoms, acyl group (preferably 2 to 12 carbon atoms), alkoxycarbonyloxy group (preferably 2 to 7 carbon atoms), alkylthio group (preferably 1 to 15 carbon atoms), alkylsulfonyl group (Preferably having 1 to 15 carbon atoms), alkyliminosulfonyl group (preferably having 2 to 15 carbon atoms), aryl Ruoxysulfonyl group (preferably having 6 to 20 carbon atoms), alkylaryloxysulfonyl group (preferably having 7 to 20 carbon atoms), cycloalkylaryloxysulfonyl group (preferably having 10 to 20 carbon atoms), alkyloxyalkyloxy group (Preferably having 5 to 20 carbon atoms), a cycloalkylalkyloxyalkyloxy group (preferably having 8 to 20 carbon atoms), and the like. About the aryl group and ring structure which each group has, an alkyl group (preferably C1-C15) can further be mentioned as a substituent.

  Examples of the aliphatic moiety in the aliphatic carboxylate anion include the same alkyl group and cycloalkyl group as in the aliphatic sulfonate anion.

  Examples of the aromatic group in the aromatic carboxylate anion include the same aryl group as in the aromatic sulfonate anion.

  The aralkyl group in the aralkyl carboxylate anion is preferably an aralkyl group having 6 to 12 carbon atoms, such as benzyl group, phenethyl group, naphthylmethyl group, naphthylethyl group, naphthylbutyl group, and the like.

The alkyl group, cycloalkyl group, aryl group and aralkyl group in the aliphatic carboxylate anion, aromatic carboxylate anion and aralkylcarboxylate anion may have a substituent. Examples of the substituent of the alkyl group, cycloalkyl group, aryl group and aralkyl group in the aliphatic carboxylate anion, aromatic carboxylate anion and aralkylcarboxylate anion include, for example, the same halogen atom and alkyl as in the aromatic sulfonate anion Group, cycloalkyl group, alkoxy group, alkylthio group and the like.
Examples of the sulfonylimide anion include saccharin anion.

  The alkyl group in the bis (alkylsulfonyl) imide anion and tris (alkylsulfonyl) methyl anion is preferably an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, An isobutyl group, a sec-butyl group, a pentyl group, a neopentyl group, and the like can be given. Examples of substituents for these alkyl groups include halogen atoms, alkyl groups substituted with halogen atoms, alkoxy groups, alkylthio groups, alkyloxysulfonyl groups, aryloxysulfonyl groups, cycloalkylaryloxysulfonyl groups, and the like. Alkyl groups substituted with fluorine atoms are preferred.

  Examples of other non-nucleophilic anions include fluorinated phosphorus, fluorinated boron, and fluorinated antimony.

Examples of the non-nucleophilic anion of Z ⁻ include an aliphatic sulfonate anion in which the α-position of the sulfonic acid is substituted with a fluorine atom, an aromatic sulfonate anion substituted with a fluorine atom or a group having a fluorine atom, and an alkyl group. A bis (alkylsulfonyl) imide anion substituted with a fluorine atom and a tris (alkylsulfonyl) methide anion wherein an alkyl group is substituted with a fluorine atom are preferred. The non-nucleophilic anion is more preferably a perfluoroaliphatic sulfonic acid anion having 4 to 8 carbon atoms, a benzenesulfonic acid anion having a fluorine atom, still more preferably a nonafluorobutanesulfonic acid anion, a perfluorooctanesulfonic acid anion, It is a pentafluorobenzenesulfonic acid anion and 3,5-bis (trifluoromethyl) benzenesulfonic acid anion.

Further, the non-nucleophilic anion of Z ⁻ may have a structure represented by the following general formula (Xa) or general formula (Xb).

  In general formula (Xa), R represents a hydrogen atom or an organic group, preferably an organic group having 1 to 40 carbon atoms, more preferably an organic group having 3 to 20 carbon atoms. Most preferably, it is an organic group represented by XI).

The organic group for R may have one or more carbon atoms, and preferably, the atom bonded to the oxygen atom in the ester bond represented by the general formula (Xa) is a carbon atom, such as an alkyl group, Examples include a cycloalkyl group, an aryl group, an aralkyl group, and a group having a lactone structure, and the chain may have a hetero atom such as an oxygen atom or a sulfur atom. These may have each other as a substituent, and may have a substituent such as a hydroxyl group, an acyl group, an acyloxy group, an oxy group (═O), or a halogen atom.

  In formula (XI), Rc represents a monocyclic or polycyclic organic group having 3 to 30 carbon atoms which may contain a cyclic ether, a cyclic thioether, a cyclic ketone, a cyclic carbonate, a lactone, or a lactam structure. Y is a hydroxyl group, a halogen atom, a cyano group, a carboxyl group, a hydrocarbon group having 1 to 10 carbon atoms, a hydroxyalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an acyl having 1 to 10 carbon atoms. Group, an alkoxycarbonyl group having 2 to 10 carbon atoms, an acyloxy group having 2 to 10 carbon atoms, an alkoxyalkyl group having 2 to 10 carbon atoms, and a halogenated alkyl group having 1 to 8 carbon atoms. When m = 0 to 6 and there are a plurality of Y, they may be the same as or different from each other. n = 0-10.

The total number of carbon atoms constituting the R group represented by formula (XI) is preferably 40 or less.
It is preferable that n = 0 to 3 and Rc is a monocyclic or polycyclic organic group having 7 to 16.

  In general formula (Xb), R represents a hydrogen atom or an organic group having no polycyclic skeleton, and preferably a hydrogen atom or an organic group having 1 to 40 carbon atoms that does not have a polycyclic skeleton. More preferably, it is a C3-C20 organic group which does not have a hydrogen atom or a polycyclic skeleton. R may be different from each other or may be bonded to each other to form a ring. The organic group for R may have one or more carbon atoms. Preferably, the atom bonded to the nitrogen atom in the amide bond represented by the general formula (Xb) is a carbon atom. Examples include an alkyl group having no skeleton, a cycloalkyl group, an aryl group, an aralkyl group, and a group having a lactone structure, and the chain may have a hetero atom such as an oxygen atom or a sulfur atom. These may have each other as a substituent, and may have a substituent such as a hydroxyl group, an acyl group, an acyloxy group, an oxy group (═O), or a halogen atom.

  The molecular weight of the non-nucleophilic anion moiety represented by general formula (Xa) and general formula (Xb) is generally 300 to 1000, preferably 400 to 800, and more preferably 500 to 700.

Examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include the corresponding groups in the compounds (ZI-1), (ZI-2) and (ZI-3) described later.

In addition, the compound which has two or more structures represented by general formula (ZI) may be sufficient. For example, the general formula at least one of R ₂₀₁ to R ₂₀₃ of a compound represented by (ZI), the structures attached to at least one of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (ZI) It may be a compound.

  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 compounds, namely, compounds containing an arylsulfonium as a cation.

In the arylsulfonium compound, all of R _{201 to} R ₂₀₃ may be an aryl group, or a part of R _{201 to} R ₂₀₃ may be 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 a phenyl group or a naphthyl group, and more preferably a phenyl group. The aryl group may be an aryl group having a heterocyclic structure having an oxygen atom, a nitrogen atom, a sulfur atom or the like. Examples of the aryl group having a heterocyclic structure include a pyrrole residue (a group formed by losing one hydrogen atom from pyrrole) and a furan residue (a group formed by losing one hydrogen atom from furan). Groups), thiophene residues (groups formed by the loss of one hydrogen atom from thiophene), indole residues (groups formed by the loss of one hydrogen atom from indole), benzofuran residues ( A group formed by losing one hydrogen atom from benzofuran), a benzothiophene residue (a group formed by losing one hydrogen atom from benzothiophene), and the like. 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 or cycloalkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms and a cycloalkyl group having 3 to 15 carbon atoms, such as a methyl group, Examples thereof include an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, 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 linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, more preferably carbon. These are an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms. 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 a compound in which R _{201 to} R ₂₀₃ in formula (ZI) each independently represents an organic group having no aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.

The organic group having no aromatic ring 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 or branched 2-oxoalkyl group, 2-oxocycloalkyl group, alkoxy group. A carbonylmethyl group, particularly preferably a linear or branched 2-oxoalkyl group.

The alkyl group and cycloalkyl group of R ₂₀₁ to R _203, preferably a linear or branched alkyl group having 1 to 10 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, pentyl group), carbon Examples thereof include cycloalkyl groups of several 3 to 10 (cyclopentyl group, cyclohexyl group, norbornyl group). More preferred examples of the alkyl group include a 2-oxoalkyl group and an alkoxycarbonylmethyl group. More preferred examples of the cycloalkyl group include a 2-oxocycloalkyl group.

The 2-oxoalkyl group may be either linear or branched, and a group having> C = O at the 2-position of the above alkyl group is preferable.
The 2-oxocycloalkyl group is preferably a group having> C═O at the 2-position of the cycloalkyl group.

  The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkoxy group having 1 to 5 carbon atoms (methoxy group, ethoxy group, propoxy group, butoxy group, 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.
R _x and R _y independently represents an alkyl group, a cycloalkyl group, an allyl group or a vinyl group.

Any two or more of R _{1c to} R _5c , R _6c and R _7c , and R _x and R _y may be bonded to each other to form a ring structure, and this ring structure includes an oxygen atom and a sulfur atom. , An ester bond and an amide bond may be included. Examples of the group formed by combining any two or more of R _{1c to} R _5c , R _6c and R _7c , and R _x and R _y include a butylene group and a pentylene group.
Zc ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as Z ^{− in} formula (ZI).

The alkyl group as R _1c to R _7c may be linear or branched may be any of, for example, alkyl group having 1 to 20 carbon atoms, preferably 1 to 12 linear or branched alkyl group having a carbon number ( Examples thereof include a methyl group, an ethyl group, a linear or branched propyl group, a linear or branched butyl group, and a linear or branched pentyl group. Examples of the cycloalkyl group include cyclohexane having 3 to 8 carbon atoms. An alkyl group (for example, a cyclopentyl group, a cyclohexyl group) can be mentioned.

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 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 and cycloalkyl group as R _x and R _y include the same alkyl group and cycloalkyl group as in R _{1c to} R _7c , such as a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxy group. A carbonylmethyl group is more preferred.

Examples of the 2-oxoalkyl group and 2-oxocycloalkyl 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 in R _{1c to} R _5c .

R _x and R _y are preferably an alkyl group or cycloalkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more alkyl groups or cycloalkyl groups.

In general formulas (ZII) and (ZIII),
R ₂₀₄ to R ₂₀₇ each independently represents an aryl group, an alkyl group or a 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. Aryl group R ₂₀₄ to R ₂₀₇ represents an oxygen atom, a nitrogen atom, may be an aryl group having a heterocyclic structure having a sulfur atom and the like. Examples of the aryl group having a heterocyclic structure include a pyrrole residue (a group formed by losing one hydrogen atom from pyrrole) and a furan residue (a group formed by losing one hydrogen atom from furan). Groups), thiophene residues (groups formed by the loss of one hydrogen atom from thiophene), indole residues (groups formed by the loss of one hydrogen atom from indole), benzofuran residues ( A group formed by losing one hydrogen atom from benzofuran), a benzothiophene residue (a group formed by losing one hydrogen atom from benzothiophene), and the like.

The alkyl group and cycloalkyl group in R ₂₀₄ to R _207, preferably a linear or branched alkyl group having 1 to 10 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, pentyl group), carbon Examples thereof include cycloalkyl groups of several 3 to 10 (cyclopentyl group, cyclohexyl group, norbornyl group).

Aryl group, alkyl group of R ₂₀₄ to R _207, cycloalkyl groups may have a substituent. Aryl group, alkyl group of R ₂₀₄ to R _207, the cycloalkyl group substituent which may be possessed by, 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 (for example, having 6 to 15 carbon atoms), an alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, and a phenylthio group.

Z ⁻ represents a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of Z ^{− in} formula (ZI).
Examples of the acid generator further include compounds represented by the following general formulas (ZIV), (ZV), and (ZVI).

In general formulas (ZIV) to (ZVI),
Ar ₃ and Ar ₄ each independently represents an aryl group. R ₂₀₈ , R ₂₀₉ and R ₂₁₀ each independently represents an alkyl group, a cycloalkyl group or an aryl group.
A represents an alkylene group, an alkenylene group or an arylene group.
Among the acid generators, compounds represented by the general formulas (ZI) to (ZIII) are more preferable.

Further, the acid generator is preferably a compound that generates an acid having one sulfonic acid group or imide group, more preferably a compound that generates monovalent perfluoroalkanesulfonic acid, or a monovalent fluorine atom or fluorine atom. A compound that generates an aromatic sulfonic acid substituted with a group containing fluorinated acid, or a compound that generates a monovalent fluorine atom or imide acid substituted with a group containing a fluorine atom, and even more preferably, It is a sulfonium salt of a substituted alkanesulfonic acid, a fluorine-substituted benzenesulfonic acid, a fluorine-substituted imide acid or a fluorine-substituted methide acid. The acid generator that can be used is particularly preferably a fluorinated substituted alkane sulfonic acid, a fluorinated substituted benzene sulfonic acid or a fluorinated substituted imido acid whose pKa of the generated acid is pKa = -1 or less, and the sensitivity is improved. .
Among acid generators, particularly preferred examples are given below.

[(B) Resin whose solubility in an alkaline developer is increased by the action of acid]
The resin of component (B) is a resin whose solubility in an alkaline developer increases by the action of an acid, and decomposes into the main chain or side chain of the resin, or both of the main chain and side chain by the action of acid, It is a resin having a group that generates an alkali-soluble group (hereinafter also referred to as “acid-decomposable group”).

  Alkali-soluble groups include phenolic hydroxyl groups, carboxyl groups, fluorinated alcohol groups, sulfonic acid groups, sulfonamido groups, sulfonylimide groups, (alkylsulfonyl) (alkylcarbonyl) methylene groups, (alkylsulfonyl) (alkylcarbonyl) imides. Group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, tris (alkylsulfonyl) methylene group, etc. Is mentioned.

  Preferred alkali-soluble groups include carboxyl groups, fluorinated alcohol groups (preferably hexafluoroisopropanol), and sulfonic acid groups.

A preferable group as the acid-decomposable group is a group in which the hydrogen atom of these alkali-soluble groups is substituted with a group capable of leaving with an acid.
Examples of the group leaving with an acid include -C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), -C (R ₃₆ ) (R ₃₇ ) (OR ₃₉ ), -C (R ₀₁ ) (R ₀₂ ). ) (OR ₃₉ ) and the like.
In the formula, R _{36 to} R ₃₉ each independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an alkenyl group. R ₃₆ and R ₃₇ may be bonded to each other to form a ring.
R _{01 and} R ₀₂ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group.
The acid-decomposable group is preferably a cumyl ester group, an enol ester group, an acetal ester group, a tertiary alkyl ester group or the like. More preferably, it is a tertiary alkyl ester group.

The resin as the component (B) preferably has a repeating unit having an acid-decomposable group. The repeating unit having an acid-decomposable group is preferably a repeating unit represented by the following general formula (AI).

In general formula (AI),
Xa ₁ represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.
T represents a single bond or a divalent linking group.
An alkyl group (monocyclic or polycyclic) may be formed.
Examples of the divalent linking group for T include an alkylene group, —COO—Rt— group, —O—Rt— group, and the like. In the formula, Rt represents an alkylene group or a cycloalkylene group.
T is preferably a single bond or a —COO—Rt— group. Rt is preferably an alkylene group having 1 to 5 carbon atoms, more preferably a —CH ₂ — group or a — (CH ₂ ) ₃ — group.

The alkyl group of Rx _{1 to} Rx ₃ is preferably an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a t-butyl group.
Examples of the cycloalkyl group represented by Rx _{1 to} Rx ₃ include monocyclic cycloalkyl groups such as cyclopentyl group and cyclohexyl group, polycyclic cycloalkyl groups such as norbornyl group, tetracyclodecanyl group, tetracyclododecanyl group, and adamantyl group. Groups are preferred.

Examples of the cycloalkyl group formed by combining at least two of Rx _{1 to} Rx ₃ include a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, A polycyclic cycloalkyl group such as an adamantyl group is preferred.
It is preferable that Rx ₁ is a methyl group or an ethyl group, and Rx ₂ and Rx ₃ are bonded to form the above-described cycloalkyl group.
As for the content rate of the repeating unit which has an acid-decomposable group, 20-50 mol% is preferable with respect to all the repeating units in resin (B), More preferably, it is 25-45 mol%.
Although the specific example of the repeating unit which has a preferable acid-decomposable group is shown below, this invention is not limited to this.

In the formula shown below, Xa ₁ represents H, CH ₃ , CF ₃ , or CH ₂ OH.

The resin of component (B) preferably further has a repeating unit having at least one group selected from a lactone group, a hydroxyl group, a cyano group, and an alkali-soluble group.
The repeating unit having a lactone group that may be contained in the component (B) resin will be described.
Any lactone group can be used as long as it has a lactone structure, but it is preferably a 5- to 7-membered ring lactone structure, and forms a bicyclo structure or a spiro structure in the 5- to 7-membered ring lactone structure. The other ring structure is preferably condensed. It is more preferable to have a repeating unit having a lactone structure represented by any of the following general formulas (LC1-1) to (LC1-16). The lactone structure may be directly bonded to the main chain. Preferred lactone structures are (LC1-1), (LC1-4), (LC1-5), (LC1-6), (LC1-13), (LC1-14), and a specific lactone structure is used. This improves line edge roughness and development defects.

The lactone structure moiety may or may not have a substituent (Rb ₂ ). Preferred substituents (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 1 to 8 carbon atoms, and a carboxyl group. , Halogen atom, hydroxyl group, cyano group, acid-decomposable group and the like. More preferably, they are a C1-C4 alkyl group, a cyano group, and an acid-decomposable group. n ₂ represents an integer of 0-4. When n ₂ is 2 or more, a plurality of substituents (Rb ₂ ) may be the same or different, and a plurality of substituents (Rb ₂ ) may be bonded to form a ring. .

Examples of the repeating unit having a lactone structure represented by any one of the general formulas (LC1-1) to (LC1-16) include a repeating unit represented by the following general formula (AII).

In general formula (AII),
Rb ₀ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms. Preferred substituents that the alkyl group represented by Rb ₀ may have include a hydroxyl group and a halogen atom. Examples of the halogen atom for Rb ₀ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Preferred are a hydrogen atom, a methyl group, a hydroxymethyl group, and a trifluoromethyl group, and a hydrogen atom and a methyl group are particularly preferred.

Ab represents a single bond, an alkylene group, a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, or a divalent linking group obtained by combining these. Preferably a single bond, -Ab ₁ -CO ₂ - is a divalent linking group represented by.

Ab ₁ is a linear, branched alkylene group, monocyclic or polycyclic cycloalkylene group, preferably a methylene group, an ethylene group, a cyclohexylene group, an adamantylene group or a norbornylene group.
V represents a group having a structure represented by any one of the general formulas (LC1-1) to (LC1-16).

  The repeating unit having a lactone group usually has an optical isomer, but any optical isomer may be used. One optical isomer may be used alone, or a plurality of optical isomers may be mixed and used. When one kind of optical isomer is mainly used, the optical purity (ee) thereof is preferably 90 or more, more preferably 95 or more.

As for the content rate of the repeating unit which has a lactone group, 15-60 mol% is preferable with respect to all the repeating units in resin (B), More preferably, it is 20-50 mol%, More preferably, it is 30-50 mol%.
Specific examples of the repeating unit having a lactone group are listed below, but the present invention is not limited thereto.

Particularly preferred repeating units having a lactone group include the following repeating units. By selecting an optimal lactone group, the pattern profile and the density dependence become good.

The resin as the component (B) preferably has a repeating unit having a hydroxyl group or a cyano group. This improves the substrate adhesion and developer compatibility. The repeating unit having a hydroxyl group or a cyano group is preferably a repeating unit having an alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group. The alicyclic hydrocarbon structure in the alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group is preferably an adamantyl group, a diamantyl group, or a norbornane group. As the alicyclic hydrocarbon structure substituted with a preferred hydroxyl group or cyano group, partial structures represented by the following formulas (VIIa) to (VIId) are preferred.

In general formulas (VIIa) to (VIIc),
R ₂ c to R ₄ c each independently represents a hydrogen atom, a hydroxyl group or a cyano group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group or a cyano group. Preferably, one or two of R ₂ c to R ₄ c are a hydroxyl group and the remaining is a hydrogen atom. In general formula (VIIa), more preferably, _two of R ₂ c to R ₄ c are hydroxyl groups and the remaining are hydrogen atoms.

Examples of the repeating unit having a partial structure represented by the general formulas (VIIa) to (VIId) include the repeating units represented by the following general formulas (AIIa) to (AIId).

In the general formulas (AIIa) to (AIId),
R ₁ c represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.
R ₂ c to R ₄ c are in the general formula (VIIa) ~ (VIIc), same meanings as R ₂ c~R ₄ c.
The content of the repeating unit having a hydroxyl group or a cyano group is preferably from 5 to 40 mol%, more preferably from 5 to 30 mol%, still more preferably from 10 to 25 mol%, based on all repeating units in the resin (B).
Specific examples of the repeating unit having a hydroxyl group or a cyano group are given below, but the present invention is not limited thereto.

  The resin of component (B) preferably has a repeating unit having an alkali-soluble group. Examples of the alkali-soluble group include a carboxyl group, a sulfonamide group, a sulfonylimide group, a bisulsulfonylimide group, and an aliphatic alcohol (for example, hexafluoroisopropanol group) substituted with an electron-attracting group at the α-position. It is more preferable to have a repeating unit. By containing the repeating unit having an alkali-soluble group, the resolution in contact hole applications is increased. The repeating unit having an alkali-soluble group includes a repeating unit in which an alkali-soluble group is directly bonded to the main chain of the resin, such as a repeating unit of acrylic acid or methacrylic acid, or an alkali in the main chain of the resin through a linking group. Either a repeating unit to which a soluble group is bonded, or a polymerization initiator or chain transfer agent having an alkali-soluble group is used at the time of polymerization and introduced at the end of the polymer chain, and the linking group is monocyclic or polycyclic. It may have a cyclic hydrocarbon structure. Particularly preferred are repeating units of acrylic acid or methacrylic acid.

As for the content rate of the repeating unit which has an alkali-soluble group, 0-20 mol% is preferable with respect to all the repeating units in resin (B), More preferably, it is 3-15 mol%, More preferably, it is 5-10 mol%.
Specific examples of the repeating unit having an alkali-soluble group are shown below, but the present invention is not limited thereto.

  As the repeating unit having at least one group selected from a lactone group, a hydroxyl group, a cyano group and an alkali-soluble group, more preferably, a repeating unit having at least two groups selected from a lactone group, a hydroxyl group, a cyano group and an alkali-soluble group Preferably, it is a repeating unit having a cyano group and a lactone group. Particularly preferred is a repeating unit having a structure in which a cyano group is substituted on the lactone structure of (LCI-4).

  The resin of component (B) may further have a repeating unit that has an alicyclic hydrocarbon structure and does not exhibit acid decomposability. This can reduce the elution of low molecular components from the resist film to the immersion liquid during immersion exposure. Among such repeating units, preferred are repeating units of 1-adamantyl (meth) acrylate, diamantyl (meth) acrylate, tricyclodecanyl (meth) acrylate, cyclohexyl (meth) acrylate, and the like.

Specific examples of repeating units that do not exhibit acid decomposability are given below.

In addition to the above repeating structural unit, the resin of component (B) is dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general required properties of resist, such as resolution, heat resistance, and sensitivity. Various repeating structural units can be included for the purpose of adjusting the above.
Examples of such repeating structural units include, but are not limited to, repeating structural units corresponding to the following monomers.

Thereby, the performance required for the resin of the component (B), in particular,
(1) Solubility in coating solvent,
(2) Film formability (glass transition point),
(3) Alkali developability,
(4) Membrane slip (hydrophobic, alkali-soluble group selection),
(5) Adhesion of unexposed part to substrate,
(6) Dry etching resistance,
Etc. can be finely adjusted.

  As such a monomer, for example, a compound having one addition polymerizable unsaturated bond selected from acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, etc. Etc.

In addition, any addition-polymerizable unsaturated compound that can be copolymerized with monomers corresponding to the above various repeating structural units may be copolymerized.
In the component (B) resin, the molar ratio of each repeating structural unit is the resist dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general resist performance required for resolving power and heat resistance. In order to adjust the sensitivity and the like, it is set as appropriate.

  When the positive photosensitive composition of the present invention is used for ArF exposure, the resin of component (B) preferably has no aromatic group from the viewpoint of transparency to ArF light.

  As the resin of component (B), preferably, all of the repeating units are composed of (meth) acrylate-based repeating units. In this case, all of the repeating units are methacrylate repeating units, all of the repeating units are acrylate repeating units, or all of the repeating units are methacrylate repeating units and acrylate repeating units. Although it can be used, the acrylate-based repeating unit is preferably 50 mol% or less of the total repeating units. More preferably, the (meth) acrylate repeating unit having an acid-decomposable group represented by the general formula (AI) is 20 to 50 mol%, the (meth) acrylate repeating unit having a lactone group is 20 to 50 mol%, It is a copolymer having 5 to 30 mol% of (meth) acrylate-based repeating units having an alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group, and further containing 0 to 20 mol% of other (meth) acrylate-based repeating units. .

When the positive photosensitive composition of the present invention is irradiated with KrF excimer laser light, electron beam, X-ray, or high energy light (EUV, etc.) having a wavelength of 50 nm or less, the resin of component (B) is a hydroxystyrene repeating unit. It is preferable to have. More preferably, hydroxystyrene / hydroxystyrene copolymer protected with an acid-decomposable group and hydroxystyrene / (meth) acrylic acid tertiary alkyl ester are preferred.
Specific examples of the resin having a hydroxystyrene repeating unit used in the present invention are shown below, but the present invention is not limited thereto.

In the above specific example, tBu represents a t-butyl group.
The content of the group that can be decomposed by an acid is determined by the number of groups (B) that can be decomposed by an acid in the resin and the number of alkali-soluble groups that are not protected by a group capable of leaving by an acid (S). B + S). The content is preferably 0.01 to 0.7, more preferably 0.05 to 0.50, and still more preferably 0.05 to 0.40.

  The resin of component (B) can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, a monomer polymerization method in which a monomer species and an initiator are dissolved in a solvent and the polymerization is performed by heating, and a solution of the monomer species and the initiator is dropped into the heating solvent over 1 to 10 hours. The dropping polymerization method is added, and the dropping polymerization method is preferable. Examples of the reaction solvent include ethers such as tetrahydrofuran, 1,4-dioxane, diisopropyl ether, ketones such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate, amide solvents such as dimethylformamide and dimethylacetamide, Furthermore, the solvent which melt | dissolves the composition of this invention like the below-mentioned propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and cyclohexanone is mentioned. More preferably, the polymerization is performed using the same solvent as the solvent used in the positive photosensitive composition of the present invention. Thereby, generation | occurrence | production of the particle at the time of a preservation | save can be suppressed.

  The polymerization reaction is preferably performed in an inert gas atmosphere such as nitrogen or argon. As a polymerization initiator, a commercially available radical initiator (azo initiator, peroxide, etc.) is used to initiate the polymerization. As the radical initiator, an azo initiator is preferable, and an azo initiator having an ester group, a cyano group, or a carboxyl group is preferable. Preferred initiators include azobisisobutyronitrile, azobisdimethylvaleronitrile, dimethyl 2,2′-azobis (2-methylpropionate) and the like. If desired, an initiator is added or added in portions, and after completion of the reaction, it is put into a solvent and a desired polymer is recovered by a method such as powder or solid recovery. The concentration of the reaction is 5 to 50% by mass, preferably 10 to 30% by mass. The reaction temperature is usually 10 ° C to 150 ° C, preferably 30 ° C to 120 ° C, more preferably 60-100 ° C.

  The weight average molecular weight of the component (B) resin is preferably 1,000 to 200,000, more preferably 2,000 to 20,000, and still more preferably 3,000 as a polystyrene-converted value by the GPC method. ˜15,000, particularly preferably 3,000 to 10,000. By setting the weight average molecular weight to 1,000 to 200,000, deterioration of heat resistance and dry etching resistance can be prevented, developability is deteriorated, and viscosity is increased, resulting in deterioration of film forming property. Can be prevented.

  The degree of dispersion (molecular weight distribution) is usually 1 to 3, preferably 1 to 2.6, more preferably 1 to 2, and particularly preferably 1.4 to 1.7. The smaller the molecular weight distribution, the better the resolution and the resist shape, and the smoother the side wall of the resist pattern, the better the roughness.

In the positive photosensitive composition of the present invention, the blending amount of the resin as the component (B) in the entire composition is preferably 50 to 99.9% by mass, more preferably 60 to 99.0% by mass in the total solid content. %.
In the present invention, the resin of component (B) may be used alone or in combination.

[Basic compounds]
The positive resist composition of the present invention preferably contains a basic compound in order to reduce changes in performance over time from exposure to heating.
Preferred examples of the basic compound include compounds having structures represented by the following formulas (A) to (E).

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

About the said alkyl group, as an alkyl group which has a substituent, a C1-C20 aminoalkyl group, a C1-C20 hydroxyalkyl group, or a C1-C20 cyanoalkyl group is preferable.
R ²⁰³ , R ²⁰⁴ , R ²⁰⁵ and R ²⁰⁶ may be the same or different and each represents an alkyl group having 1 to 20 carbon atoms.

  The alkyl groups in the general formulas (A) and (E) are more preferably unsubstituted.

  Preferred compounds include guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, piperidine and the like, and more preferred compounds include imidazole structure, diazabicyclo structure, onium hydroxide structure, onium carboxylate Examples thereof include a compound having a structure, a trialkylamine structure, an aniline structure or a pyridine 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 an onium hydroxide structure include tetrabutylammonium hydroxide, triarylsulfonium hydroxide, phenacylsulfonium hydroxide, sulfonium hydroxide having a 2-oxoalkyl group, specifically, triphenylsulfonium hydroxide, tris ( and t-butylphenyl) sulfonium hydroxide, bis (t-butylphenyl) iodonium hydroxide, phenacylthiophenium hydroxide, 2-oxopropylthiophenium hydroxide, and the like. As the compound having an onium carboxylate structure, an anion portion of the compound having an onium hydroxide structure is converted to a carboxylate, and examples thereof include acetate, adamantane-1-carboxylate, and perfluoroalkylcarboxylate. Examples of the compound having a trialkylamine structure include tri (n-butyl) amine and tri (n-octyl) amine. 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.

  Preferred examples of the basic compound further include an amine compound having a phenoxy group, an ammonium salt compound having a phenoxy group, an amine compound having a sulfonic acid ester group, and an ammonium salt compound having a sulfonic acid ester group.

As the amine compound, a primary, secondary or tertiary amine compound can be used, and an amine compound in which at least one alkyl group is bonded to a nitrogen atom is preferable. The amine compound is more preferably a tertiary amine compound. As long as at least one alkyl group (preferably having 1 to 20 carbon atoms) is bonded to a nitrogen atom, the amine compound has an cycloalkyl group (preferably having 3 to 20 carbon atoms) or an aryl group (preferably having 3 to 20 carbon atoms). Preferably C6-C12) may be bonded to a nitrogen atom. The amine compound preferably has an oxygen atom in the alkyl chain and an oxyalkylene group is formed. The number of oxyalkylene groups is one or more in the molecule, preferably 3 to 9, and more preferably 4 to 6. Among the oxyalkylene groups, an oxyethylene group (—CH ₂ CH ₂ O—) or an oxypropylene group (—CH (CH ₃ ) CH ₂ O— or —CH ₂ CH ₂ CH ₂ O—) is preferable, and more preferably oxy Ethylene group.

As the ammonium salt compound, a primary, secondary, tertiary, or quaternary ammonium salt compound can be used, and an ammonium salt compound in which at least one alkyl group is bonded to a nitrogen atom is preferable. As long as at least one alkyl group (preferably having 1 to 20 carbon atoms) is bonded to a nitrogen atom, the ammonium salt compound has a cycloalkyl group (preferably having 3 to 20 carbon atoms) or an aryl group in addition to the alkyl group. (Preferably having 6 to 12 carbon atoms) may be bonded to a nitrogen atom. The ammonium salt compound preferably has an oxygen atom in the alkyl chain and an oxyalkylene group is formed. The number of oxyalkylene groups is one or more in the molecule, preferably 3 to 9, and more preferably 4 to 6. Among the oxyalkylene groups, an oxyethylene group (—CH ₂ CH ₂ O—) or an oxypropylene group (—CH (CH ₃ ) CH ₂ O— or —CH ₂ CH ₂ CH ₂ O—) is preferable, and more preferably oxy Ethylene group. Examples of the anion of the ammonium salt compound include halogen atoms, sulfonates, borates, and phosphates. Among them, halogen atoms and sulfonates are preferable. As the halogen atom, chloride, bromide, and iodide are particularly preferable. As the sulfonate, an organic sulfonate having 1 to 20 carbon atoms is particularly preferable. Examples of the organic sulfonate include alkyl sulfonates having 1 to 20 carbon atoms and aryl sulfonates. The alkyl group of the alkyl sulfonate may have a substituent, and examples of the substituent include fluorine, chlorine, bromine, alkoxy groups, acyl groups, and aryl groups. Specific examples of the alkyl sulfonate include methane sulfonate, ethane sulfonate, butane sulfonate, hexane sulfonate, octane sulfonate, benzyl sulfonate, trifluoromethane sulfonate, pentafluoroethane sulfonate, and nonafluorobutane sulfonate. Examples of the aryl group of the aryl sulfonate include a benzene ring, a naphthalene ring, and an anthracene ring. The benzene ring, naphthalene ring and anthracene ring may have a substituent, and the substituent is preferably a linear or branched alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms. Specific examples of the linear or branched alkyl group and cycloalkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, i-butyl, t-butyl, n-hexyl, cyclohexyl and the like. Examples of the other substituent include an alkoxy group having 1 to 6 carbon atoms, a halogen atom, cyano, nitro, an acyl group, and an acyloxy group.

  The amine compound having a phenoxy group and the ammonium salt compound having a phenoxy group are those having a phenoxy group at the terminal opposite to the nitrogen atom of the alkyl group of the amine compound or ammonium salt compound. The phenoxy group may have a substituent. Examples of the substituent of the phenoxy group include an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, a carboxyl group, a carboxylic acid ester group, a sulfonic acid ester group, an aryl group, an aralkyl group, an acyloxy group, and an aryloxy group. Etc. The substitution position of the substituent may be any of the 2-6 positions. The number of substituents may be any in the range of 1 to 5.

It is preferable to have at least one oxyalkylene group between the phenoxy group and the nitrogen atom. The number of oxyalkylene groups is one or more in the molecule, preferably 3 to 9, and more preferably 4 to 6. Among the oxyalkylene groups, an oxyethylene group (—CH ₂ CH ₂ O—) or an oxypropylene group (—CH (CH ₃ ) CH ₂ O— or —CH ₂ CH ₂ CH ₂ O—) is preferable, and more preferably oxy Ethylene group.

  In the amine compound having a sulfonic acid ester group and the ammonium salt compound having a sulfonic acid ester group, the sulfonic acid ester group may be any of alkyl sulfonic acid ester, cycloalkyl group sulfonic acid ester, and aryl sulfonic acid ester. In the case of alkyl sulfonate, the alkyl group has 1 to 20 carbon atoms, in the case of cycloalkyl sulfonate ester, the cycloalkyl group has 3 to 20 carbon atoms, and in the case of aryl sulfonate ester, the aryl group has 6 carbon atoms. ~ 12 are preferred. Alkyl sulfonic acid ester, cycloalkyl sulfonic acid ester, and aryl sulfonic acid ester may have a substituent. Examples of the substituent include a halogen atom, a cyano group, a nitro group, a carboxyl group, a carboxylic acid ester group, and a sulfonic acid. An ester group is preferred.

It is preferable to have at least one oxyalkylene group between the sulfonate group and the nitrogen atom. The number of oxyalkylene groups is one or more in the molecule, preferably 3 to 9, and more preferably 4 to 6. Among the oxyalkylene groups, an oxyethylene group (—CH ₂ CH ₂ O—) or an oxypropylene group (—CH (CH ₃ ) CH ₂ O— or —CH ₂ CH ₂ CH ₂ O—) is preferable, and more preferably oxy Ethylene group.
These basic compounds are used alone or in combination of two or more.

  The usage-amount of a basic compound is 0.001-10 mass% normally on the basis of the total solid of a positive resist composition, Preferably it is 0.01-5 mass%.

  The mixing ratio of the acid generator and the basic compound in the composition is preferably acid generator / basic compound (molar ratio) = 2.5 to 300. In other words, the molar ratio is preferably 2.5 or more from the viewpoint of sensitivity and resolution, and is preferably 300 or less from the viewpoint of suppressing the reduction in resolution due to the thickening of the resist pattern over time until post-exposure heat treatment. The acid generator / basic compound (molar ratio) is more preferably 5.0 to 200, still more preferably 7.0 to 150.

[Surfactant]
The positive resist composition of the present invention preferably further contains a surfactant, and a fluorine-based and / or silicon-based surfactant (fluorine-based surfactant, silicon-based surfactant, fluorine atom and silicon atom It is more preferable to contain either one or two or more surfactants having both.

  When the positive resist composition of the present invention contains the above-described surfactant, a resist pattern with good adhesion and low development defects can be obtained with good sensitivity and resolution when using an exposure light source of 250 nm or less, particularly 220 nm or less. It becomes possible.

  Examples of the fluorine-based and / or silicon-based surfactant include, for example, JP-A No. 62-36663, JP-A No. 61-226746, JP-A No. 61-226745, JP-A No. 62-170950, JP 63-34540 A, JP 7-230165 A, JP 8-62834 A, JP 9-54432 A, JP 9-5988 A, JP 2002-277862 A, US Patent Nos. 5,405,720, 5,360,692, 5,529,881, 5,296,330, 5,436,098, 5,576,143, 5,294,511, 5,824,451 Surfactant can be mentioned, The following commercially available surfactant can also be used as it is.

  Examples of commercially available surfactants that can be used include F-top EF301, EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430, 431, 4430 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176, F189 , F113, F110, F177, F120, R08 (Dainippon Ink Chemical Co., Ltd.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.), Troisol S-366 (Manufactured by Troy Chemical Co., Ltd.), GF-300, GF-150 (manufactured by Toagosei Chemical Co., Ltd.), Surflon S-393 (manufactured by Seimi Chemical Co., Ltd.), F-top EF121, EF122A, EF122B, RF122C, EF125M , EF135M, EF351, 352, EF801, EF802, EF 01 (manufactured by Gemco), PF636, PF656, PF6320, PF6520 (manufactured by OMNOVA), FTX-204G, 208G, 218G, 230G, 204D, 208D, 212D, 218D, 222D (manufactured by Neos) 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 link) or poly (block link of oxyethylene and oxypropylene) 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 ₃ F ₇ group and (poly (oxy) And a copolymer of (ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate).

In the present invention, other surfactants other than fluorine-based and / or silicon-based surfactants can also be used. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether, etc. Sorbitans such as polyoxyethylene alkyl aryl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate Fatty acid esters, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopa Mite - DOO, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, may be mentioned polyoxyethylene sorbitan tristearate nonionic surfactants of polyoxyethylene sorbitan fatty acid esters such as such.
These surfactants may be used alone or in several combinations.

  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 solid content in the positive resist composition.

〔solvent〕
Solvents that can be used when preparing the positive resist composition by dissolving the above components include, for example, alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, alkyl lactate ester, and alkyl alkoxypropionate. And organic solvents such as cyclic lactones (preferably having 4 to 10 carbon atoms), monoketone compounds which may contain rings (preferably having 4 to 10 carbon atoms), alkylene carbonates, alkyl alkoxyacetates and alkyl pyruvates. it can.

  Examples of the alkylene glycol monoalkyl ether carboxylate include propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, propylene glycol monomethyl ether propionate, propylene glycol monoethyl Preferred examples include ether propionate, ethylene glycol monomethyl ether acetate, and ethylene glycol monoethyl ether acetate.

  Preferred examples of the alkylene glycol monoalkyl ether include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether.

Preferred examples of the alkyl lactate include methyl lactate, ethyl lactate, propyl lactate and butyl lactate.
Preferable examples of the alkyl alkoxypropionate include ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, and ethyl 3-methoxypropionate.

  Examples of the cyclic lactone include β-propiolactone, β-butyrolactone, γ-butyrolactone, α-methyl-γ-butyrolactone, β-methyl-γ-butyrolactone, γ-valerolactone, γ-caprolactone, and γ-octano. Preferred are iclactone and α-hydroxy-γ-butyrolactone.

  Examples of the monoketone compound which may contain a ring include 2-butanone, 3-methylbutanone, pinacolone, 2-pentanone, 3-pentanone, 3-methyl-2-pentanone, 4-methyl-2-pentanone, 2 -Methyl-3-pentanone, 4,4-dimethyl-2-pentanone, 2,4-dimethyl-3-pentanone, 2,2,4,4-tetramethyl-3-pentanone, 2-hexanone, 3-hexanone, 5-methyl-3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, 2,6-dimethyl-4-heptanone, 2-octanone, 3-octanone, 2-nonanone, 3-nonanone, 5-nonanone, 2-decanone, 3-decanone, 4-decanone, 5-hexen-2-one, -Penten-2-one, cyclopentanone, 2-methylcyclopentanone, 3-methylcyclopentanone, 2,2-dimethylcyclopentanone, 2,4,4-trimethylcyclopentanone, cyclohexanone, 3-methyl Cyclohexanone, 4-methylcyclohexanone, 4-ethylcyclohexanone, 2,2-dimethylcyclohexanone, 2,6-dimethylcyclohexanone, 2,2,6-trimethylcyclohexanone, cycloheptanone, 2-methylcycloheptanone, 3-methylcyclo A preferred example is heptanone.

Preferred examples of the alkylene carbonate include propylene carbonate, vinylene carbonate, ethylene carbonate, and butylene carbonate.
Examples of the alkyl alkoxyacetate include 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 2- (2-ethoxyethoxy) ethyl acetate, 3-methoxy-3-methylbutyl acetate, and 1-methoxy-acetate. 2-propyl is preferred.
Preferred examples of the alkyl pyruvate include methyl pyruvate, ethyl pyruvate, and propyl pyruvate.

As a solvent which can be preferably used, a solvent having a boiling point of 130 ° C. or higher under normal temperature and normal pressure can be mentioned. Specifically, cyclopentanone, γ-butyrolactone, cyclohexanone, ethyl lactate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, ethyl 3-ethoxypropionate, ethyl pyruvate, 2-ethoxyethyl acetate, acetic acid -2- (2-ethoxyethoxy) ethyl and propylene carbonate are mentioned.
In the present invention, the above solvents may be used alone or in combination of two or more.

In this invention, you may use the mixed solvent which mixed the solvent which contains a hydroxyl group in a structure, and the solvent which does not contain a hydroxyl group as an organic solvent.
Examples of the solvent containing a hydroxyl group include ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethyl lactate, and the like. Particularly preferred are propylene glycol monomethyl ether and ethyl lactate.

  Examples of the solvent not containing a hydroxyl group include propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, butyl acetate, N-methylpyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide and the like. Among these, propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, and butyl acetate are particularly preferred, and propylene glycol monomethyl ether acetate, ethyl ethoxypropionate. 2-heptanone is most preferred.

  The mixing ratio (mass) of the solvent containing a hydroxyl group and the solvent not containing a hydroxyl group is 1/99 to 99/1, preferably 10/90 to 90/10, more preferably 20/80 to 60/40. . A mixed solvent containing 50% by mass or more of a solvent not containing a hydroxyl group is particularly preferred from the viewpoint of coating uniformity.

[Other additives]
In the positive resist composition of the present invention, if necessary, a dye, a plasticizer, a photosensitizer, a light absorber, and a compound that promotes solubility in a developer (for example, a phenol compound having a molecular weight of 1000 or less, An alicyclic or aliphatic compound having a carboxyl group) or the like can be contained.

  Such phenol compounds having a molecular weight of 1000 or less can be obtained by referring to, for example, the methods described in JP-A-4-1222938, JP-A-2-28531, US Pat. No. 4,916,210, European Patent 219294, etc. It can be easily synthesized by those skilled in the art.

  Specific examples of alicyclic or aliphatic compounds having a carboxyl group include carboxylic acid derivatives having a steroid structure such as cholic acid, deoxycholic acid, lithocholic acid, adamantane carboxylic acid derivatives, adamantane dicarboxylic acid, cyclohexane carboxylic acid, cyclohexane Examples thereof include, but are not limited to, dicarboxylic acids.

<Pattern formation method>
The positive resist composition of the present invention is preferably used at a film thickness of 30 to 250 nm, more preferably at a film thickness of 30 to 200 nm, from the viewpoint of improving resolution. Such a film thickness can be obtained by setting the solid content concentration in the positive resist composition to an appropriate range to give an appropriate viscosity and improving the coating property and film forming property.

  The total solid content concentration in the positive resist composition is generally 1 to 10% by mass, more preferably 1 to 8.0% by mass, and still more preferably 1.0 to 6.0% by mass.

  The positive resist composition of the present invention is used by dissolving the above components in a predetermined organic solvent, preferably the mixed solvent, filtering the solution, and then applying the solution on a predetermined support as follows. The pore size of the filter used for filter filtration is preferably 0.1 μm or less, more preferably 0.05 μm or less, and still more preferably 0.03 μm or less made of polytetrafluoroethylene, polyethylene, or nylon.

For example, a positive resist composition is coated on a substrate (eg, silicon / silicon dioxide coating) used for manufacturing a precision integrated circuit element by an appropriate coating method such as a spinner or a coater, and dried to form a resist film. Form.
The resist film is irradiated with actinic rays or radiation through a predetermined mask, preferably baked (heated), developed and rinsed. Thereby, a good pattern can be obtained.

Examples of the actinic ray or radiation include infrared light, visible light, ultraviolet light, far ultraviolet light, X-ray, electron beam, etc., preferably 250 nm or less, more preferably 220 nm or less, particularly preferably 1 to 1. Far-ultraviolet light having a wavelength of 200 nm, specifically, KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157 nm), X-ray, electron beam, etc. ArF excimer laser, F ₂ Excimer laser, EUV (13 nm), and electron beam are preferable.

Before forming the resist film, an antireflection film may be coated on the substrate in advance.
As the antireflection film, any of an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, and amorphous silicon, and an organic film type made of a light absorber and a polymer material can be used. 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 development step, an alkaline developer is used as follows. Examples of the alkali developer for the positive resist composition include inorganic hydroxides 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, alcohol amines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide Alkaline aqueous solutions of cyclic amines such as quaternary ammonium salts such as pyrrole and pihelidine can be used.

Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline developer.
The alkali concentration of the alkali developer is usually from 0.1 to 20% by mass.
The pH of the alkali developer is usually from 10.0 to 15.0.
Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline aqueous solution.
As the rinsing liquid, pure water can be used, and an appropriate amount of a surfactant can be added.

  Further, after the development process or the rinsing process, a process of removing the developer or the rinsing liquid adhering to the pattern with a supercritical fluid can be performed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, the content of this invention is not limited by this.

Examples 1-13, Comparative Examples 1-2
<Synthesis of acid generator (A)>
[Synthesis of Compound (I-1)]
According to Patent Document 1, the following compound X was synthesized from methyl difluoro (fluorosulfonyl) acetate (manufactured by Wako Pure Chemical Industries). To 2 g of the obtained compound, 1.0 g of 1,3 dioxolan-2-yl-N-methylmethanamine and 10 ml of tetrahydrofuran were added and stirred at room temperature for 4 hours. 20 ml of t-butyl methyl ether was added to the reaction solution, and the precipitated crystals were filtered. Reslurry was performed twice with 20 ml of t-butyl methyl ether and dried. (Yield 1.70 g)

To the obtained white crystals Y, 2.3 g of triphenylsulfonium bromide, 20 g of ion-exchanged water, and 30 g of acetonitrile were added and stirred at room temperature for 2 hours. Acetonitrile was concentrated with a rotary evaporator, and 200 g of chloroform was added to the remaining aqueous layer for extraction. Furthermore, the organic layer was washed 3 times with ion-exchanged water, concentrated and dried to obtain white crystals (I-1). (Yield 0.5g)
300 MHz- ¹ H-NMR (CDCl3)
δ 4.45 (d, 2H), δ 3.80 (m, 2H), δ 4.02 (m, 2H), δ 5.00 (t, 1H), δ 7.85-7.80 (m, 15H).
[Synthesis of Compound (I-10)]
1,3 dioxolan-2-yl-N-methylmethanamine used in the synthesis of the compound (I-1) was changed to 1,4 dioxa-8-azaspiro [4,5] decane (manufactured by Aldrich), and 50 ° C. Compound (I-10) was obtained in the same manner as for Compound (I-1) except that the mixture was heated and stirred at.

[Synthesis of Compounds (I-4), (I-8), (I-9)]
Compounds (I-4), (I-8) and (I-9) were also obtained in the same manner as for compound (I-1).

<Synthesis of Resin (B)>
[Synthesis of Resin (4)]
Under a nitrogen stream, 20 g of a 6/4 (mass ratio) mixed solvent of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether was placed in a three-necked flask and heated to 80 ° C. (solvent 1). Butyrolactone methacrylate, hydroxyadamantane methacrylate and 2-methyl-2-adamantyl methacrylate are dissolved in a mixed solvent of 6/4 (mass ratio) of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether at a molar ratio of 50/10/40. A 22 mass% monomer solution (200 g) was prepared. Furthermore, 8 mol% of initiator V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) was added to the monomer, and the dissolved solution was added dropwise to (solvent 1) over 6 hours. After completion of dropping, the reaction was further carried out at 80 ° C. for 2 hours. The reaction solution was allowed to cool and then poured into 1800 ml of hexane / 200 ml of ethyl acetate. The precipitated powder was collected by filtration and dried to obtain 37 g of Resin (4).
As a result of GPC measurement using polystyrene as a standard, the obtained resin (4) had a weight average molecular weight (Mw) of 10,000 and a dispersity (Mw / Mn) of 1.8.

[Synthesis of Resins (1) to (3)]
Resins (1) to (3) were synthesized by the same synthesis method as resin (4).
The structures of the repeating units in the resins (1) to (4) are shown below, and the composition ratio of the repeating units (corresponding to each repeating unit in order from the left), weight average molecular weight (Mw), and dispersity (Mw / Mn) are shown. It is shown in 1.

<Resist preparation>
The components shown in Table 2 below were dissolved in a solvent to prepare a solution having a solid content concentration of 5% by mass for each, and this was filtered through a polyethylene filter having a pore size of 0.1 μm to prepare a positive resist composition. The prepared positive resist composition was evaluated by the following method, and the results are shown in Table 3. About each component in a table | surface, ratio when using multiple is mass ratio.

  Each component used is as follows.

[Photoacid generator]

[Basic compounds]
TPI: 2,4,5-triphenylimidazole PEA: N-phenyldiethanolamine DPA: 2,6-diisopropylphenyl alcohol PBI: 2-phenylbenzimidazole [Surfactant]
W-1: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.) (Fluorine)
W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd.) (fluorine and silicon)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) (silicon-based)
〔solvent〕
A1: Propylene glycol monomethyl ether acetate A2: γ-butyrolactone A3: Cyclohexanone B1: Propylene glycol monomethyl ether B2: Ethyl lactate <Image performance test>
[Dry exposure]
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form a 78 nm antireflection film. The positive resist composition prepared thereon was applied and baked at 130 ° C. for 60 seconds to form a 120 nm resist film. Using the obtained wafer ArF excimer laser scanner (manufactured by ASML, PAS5500 / 1100, NA0.75), exposure was performed through a 6% halftone mask of 75 nm 1: 1 line and space pattern. Thereafter, heating was performed at 130 ° C. for 60 seconds, followed by development with an aqueous tetramethylammonium hydroxide solution (2.38 mass%) for 30 seconds, rinsing with pure water, and spin drying to obtain a resist pattern.

[LWR]
In the dry exposure, the line pattern finished at 90 nm is observed with a scanning microscope (S9260 manufactured by Hitachi, Ltd.), and the distance from the reference line where the edge should be in the range of 2 μm in the longitudinal direction of the line pattern is 50 points. Measurement was performed to obtain a standard deviation, and 3σ was calculated. A smaller value indicates better performance.

[Mask Error Enhancement Factor (MEEF)]
Slope of change in size of resist pattern when the mask size is changed from 71 nm to 79 nm with the exposure amount at which a 75 nm resist pattern is obtained with a mask pattern having a mask size of 75 nm and a pitch of 150 nm and the pitch is fixed at 150 nm. Was MEEF.

  From the results in Table 3, it was found that the positive resist composition of the present invention was good in both MEEF and LWR in the characteristic evaluation by irradiation with ArF light.

Example 14, Comparative Example 3
<Resist preparation>
The components shown in Table 4 below are dissolved in a solvent, and this is filtered through a polytetrafluoroethylene filter having a pore size of 0.1 μm to prepare a positive resist solution having a solid content concentration of 8% by mass, and evaluated by the following method. The results are shown in Table 5.

<Resist evaluation>
The prepared positive resist solution was uniformly coated on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and then heated and dried on a hot plate at 120 ° C. for 60 seconds to obtain a film thickness of 0. A 15 μm resist film was prepared.

[Sensitivity and γ value]
The obtained resist film was subjected to surface exposure using EUV light (wavelength 13 nm) while changing the exposure amount in increments of 0.5 mJ / cm ^{2 in} the range of 0 to 10.0 mJ / cm ² , and at 90 ° C., 90 ° C. Baked for 2 seconds. Then, using a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution, the dissolution rate at each exposure amount was measured to obtain a sensitivity curve.

In this sensitivity curve, the exposure amount when the dissolution rate of the resist is saturated was taken as sensitivity, and the dissolution contrast (γ value) was calculated from the gradient of the linear portion of the sensitivity curve. The larger the γ value, the better the dissolution contrast.

Of the components used, the resin (5) not described in Table 2 is as follows.
(Synthesis of resin (5))
p-Acetoxystyrene and (4′-hydroxyphenyl) methacrylate were charged at a ratio (molar ratio) of 60/40 and dissolved in tetrahydrofuran to prepare 100 mL of a solution having a solid content concentration of 20% by mass. To this solution was added 3 mol% of methyl mercaptopropionate and 4 mol% of polymerization initiator V-65 manufactured by Wako Pure Chemical Industries, Ltd., and this was added dropwise to 10 mL of tetrahydrofuran heated to 60 ° C. over 4 hours in a nitrogen atmosphere. did. After completion of the dropwise addition, the reaction solution was heated for 4 hours, 1 mol% of V-65 was added again, and the mixture was stirred for 4 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 3 L of hexane, and the precipitated white powder was collected by filtration.

The composition ratio of the polymer determined from C ¹³ NMR was 58/42. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 2200, and dispersion degree (Mw / Mn) was 1.30.

  The obtained resin was vacuum-dried and then dissolved in 100 ml of dehydrated THF (tetrahydrofuran). Thereto, 10 ml of cyclohexyl vinyl ether was added and stirred, and 100 mg of p-toluenesulfonic acid was added and reacted for 3 hours. The reaction solution was neutralized by adding 1 ml of triethylamine, 200 ml of ethyl acetate was added, 500 ml of distilled water was further added, and liquid separation and washing were repeated three times. The ethyl acetate layer was reprecipitated with hexane to obtain the desired resin (5) (composition molar ratio (43/15/32/10), weight average molecular weight 2500, dispersity 1.30.

The structure of the repeating unit in the resin (5) is shown below.

  From the results in Table 5, it was found that the positive resist composition of the present invention has good sensitivity and resolution in the characteristic evaluation by irradiation with EUV light.

Claims (10)

(A) at least one compound that generates an acid represented by the following general formula (0) upon irradiation with actinic rays or radiation, and (B) a resin that increases the solubility in an alkali developer by the action of the acid. An actinic ray-sensitive or radiation-sensitive resin composition characterized by the above.

In general formula (0),
R ₁ represents an organic group.
R ₂ represents a hydrogen atom or an organic group. R ₁ and R ₂ may combine to form a monocyclic or polycyclic structure.
A represents a group that decomposes by the action of an acid or a base.
n represents 1 or 2. In the general formula (0), R ₁ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted group having an oxygen atom, a sulfur atom or a nitrogen atom in the alkyl chain, a substituted or unsubstituted cycloalkyl group, A substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted aryl group, wherein R ₂ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkyl group, A group having an oxygen atom, sulfur atom or nitrogen atom in the chain, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted aryl group; The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1. The compound (A) that generates an acid represented by the general formula (0) by irradiation with actinic rays or radiation is a compound represented by the following general formula (I): The actinic ray-sensitive or radiation-sensitive resin composition described in 1.

In the general formula (I), M ^{m +} represents an organic counter cation, and m represents an integer. R ₁ , R ₂ , A and n have the same meanings as R ₁ , R ₂ and A in the general formula (0), respectively.   A pattern forming method comprising a step of forming a film using the actinic ray-sensitive or radiation-sensitive resin composition according to claim 1, and exposing and developing the film. A compound that generates an acid represented by the following general formula (0) by irradiation with actinic rays or radiation.

In general formula (0),
R ₁ represents an organic group.
R ₂ represents a hydrogen atom or an organic group. R ₁ and R ₂ may combine to form a monocyclic or polycyclic structure.
A represents a group that decomposes by the action of an acid or a base.
n represents 1 or 2. In the general formula (0), R ₁ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted group having an oxygen atom, a sulfur atom or a nitrogen atom in the alkyl chain, a substituted or unsubstituted cycloalkyl group, A substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted aryl group, wherein R ₂ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkyl group, A group having an oxygen atom, sulfur atom or nitrogen atom in the chain, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted aryl group; 6. The compound of claim 5, wherein The said compound which generate | occur | produces the acid represented by general formula (0) by irradiation of actinic light or a radiation is a compound represented by the following general formula (I), It is characterized by the above-mentioned. Compound.

In the general formula (I), M ^{m +} represents an organic counter cation, and m represents an integer. R ₁ , R ₂ , A and n have the same meanings as R ₁ , R ₂ and A in the general formula (0), respectively.   A photoacid generator comprising the compound according to claim 5. A compound represented by the following general formula (II):

In general formula (II):
R ₁ represents an organic group.
R ₂ represents a hydrogen atom or an organic group. R ₁ and R ₂ may combine to form a monocyclic or polycyclic structure.
A represents a group that decomposes by the action of an acid or a base.
n represents 1 or 2.
M ′ ⁺ represents a monovalent metal cation. In the general formula (II), R ₁ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted group having an oxygen atom, a sulfur atom or a nitrogen atom in the alkyl chain, a substituted or unsubstituted cycloalkyl group, A substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted aryl group, wherein R ₂ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkyl group, A group having an oxygen atom, sulfur atom or nitrogen atom in the chain, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted cycloalkyl group having an oxygen atom in the ring, or a substituted or unsubstituted aryl group; 10. The compound of claim 9, wherein