JP5775264B2 - Chemically amplified photoresist composition and pattern forming method - Google Patents

Description

  The present invention relates to a chemically amplified photoresist composition and a pattern forming method, and more particularly, to chemical amplification used in semiconductor microfabrication, manufacturing of circuit boards such as liquid crystals and thermal heads, and other photofabrication processes. The present invention relates to a type photoresist composition and a pattern forming method using the same.

  In microfabrication of semiconductors, it is desirable to form a pattern with higher resolution, and a chemically amplified resist composition is required to have higher resolution, good line edge roughness, and no pattern collapse.

  In Patent Document 1, 2-ethyl-2-adamantyl methacrylate, 3-hydroxy-1-adamantyl methacrylate and α-methacryloyloxy-γ-butyrolactone are charged at a molar ratio of 50:25:25 and polymerized. A chemical amplification type comprising: a resin comprising: an acid generator comprising triphenylsulfonium · 1-((3-hydroxyadamantyl) methoxycarbonyl) difluoromethanesulfonate; a quencher comprising 2,6-diisopropylaniline; and a solvent. A photoresist composition is described (see Patent Document 1: Japanese Patent Application Laid-Open No. 2006-257078).

Patent Document 2 discloses a resin comprising a structural unit derived from the following monomers (mol% of structural unit; 40: 25: 8: 27), triphenylsulfonium perfluorooctanesulfonate and 1- (2 A chemically amplified photoresist composition composed of an acid generator composed of -oxo-2-phenylethyl) tetrahydrothiophenium perfluorobutanesulfonate, triphenylimidazole and a solvent is described (Patent Document 2). : JP 2002-341540 A).

Patent Document 3 discloses a resin comprising a structural unit derived from the following monomers (mol% of structural unit; 30:50:20) and an acid generator composed of triphenylsulfonium perfluorobutanesulfonate, A chemically amplified photoresist composition comprising triethanolamine and a solvent has been described (see Patent Document 3: Japanese Patent Application Laid-Open No. 2007-114613).

JP 2006-257078 A JP 2002-341540 A JP 2007-146613 A

  In the conventional chemically amplified photoresist composition, the resolution and line edge roughness of the obtained pattern are not always satisfactory, or pattern collapse may occur.

The present invention includes the following inventions.
[1] A chemically amplified photoresist composition comprising an acid generator (A) and a resin (B), wherein the resin (B) is at least (b1) a carboxyl group produced by the action of an acid to produce an alkali. A structural unit that is soluble in the developer,
(B2) a structural unit derived from a monomer having an adamantyl group having at least two -OX ^a groups (X ^a represents a group capable of leaving by the action of an acid), and (b3) a lactone ring A chemically amplified photoresist composition comprising units.

[2] The composition according to [1], wherein Xa in the structural unit (b2) is ^a linear, branched or cyclic tertiary aliphatic hydrocarbon group having 4 to 12 carbon atoms and having an ester bond. object.

[3] The composition according to [1] or [2], wherein Xa in the structural unit (b2) is ^a branched tertiary aliphatic hydrocarbon group having 4 to 7 carbon atoms having an ester bond.

［式（III）中、Ｒ^１は、水素原子又はメチル基を表す。
Ｒ^６及びＲ^７は、互いに独立に、水素原子、メチル基、水酸基又は−ＯＸ^ａ基を表し、ただし、Ｒ^６及びＲ^７の少なくともいずれか一方は−ＯＸ^ａ基を表す。
Ｒ^８は、メチル基を表す。
Ｘ^ａは、酸の作用により脱離し得る基を表す。
Ｚ”は、単結合又は、−［ＣＨ_２］_ｋ’−を表し、−［ＣＨ_２］_ｋ’−に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。ｋ’は、１〜１７の整数を表す。
ｎ’は、０〜１０の整数を表す。］ [4] The composition according to any one of [1] to [3], wherein the structural unit (b2) includes a structural unit represented by the formula (III).

[In Formula (III), R ¹ represents a hydrogen atom or a methyl group.
R ⁶ and R ⁷ each independently represent ^a hydrogen atom, a methyl group, a hydroxyl group or an —OX ^a group, provided that at least one of R ⁶ and R ⁷ represents an —OX ^a group.
R ⁸ represents a methyl group.
X ^a represents a group which leaves by the action of an acid.
Z ″ represents a single bond or — [CH ₂ ] _{k ′} —, and the methylene group contained in — [CH ₂ ] _{k ′} — may be substituted with an oxygen atom or a carbonyl group. , Represents an integer of 1 to 17.
n ′ represents an integer of 0 to 10. ]

[5] The monomer that leads to the structural unit represented by the formula (III) is 3,5-dihydroxy-1-adamantyl (meth) acrylate or 1- (3,5-dihydroxy-1-adamantyloxycarbonyl) methyl (meta ) The acrylate is a monomer in which the hydrogen atom of the hydroxyl group is substituted with a linear, branched or cyclic tertiary aliphatic hydrocarbon group having 4 to 12 carbon atoms having an ester bond. Composition.

［式（Ｖａ）及び式（Ｖｃ）中、Ｒ^１は、水素原子又はメチル基を表す。
Ｒ^２は、炭素数１〜８の脂肪族炭化水素基又は炭素数３〜１０の脂環式炭化水素基を表す。
Ｒ^３は、メチル基を表す。ｎは、０〜１４の整数を表す。ｎ’は、０〜３の整数を表す。
Ｚ”は、互いに独立に、単結合又は、−［ＣＨ_２］_ｋ’−を表し、−［ＣＨ_２］_ｋ’−に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。ｋ’は、１〜１７の整数を表す。］ [6] The composition according to any one of [1] to [5], wherein the structural unit (b1) is a structural unit represented by the formula (Va) or the formula (Vc).

[In Formula (Va) and Formula (Vc), R ¹ represents a hydrogen atom or a methyl group.
R ² represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 10 carbon atoms.
R ³ represents a methyl group. n represents an integer of 0 to 14. n ′ represents an integer of 0 to 3.
Z ″ represents, independently of each other, a single bond or — [CH ₂ ] _{k ′} —, and the methylene group contained in — [CH ₂ ] _{k ′} — may be substituted with an oxygen atom or a carbonyl group. K ′ represents an integer of 1 to 17.]

[7] Monomers that lead to the structural unit represented by the formula (Va) are 2-methyl-2-adamantyl (meth) acrylate, 2-ethyl-2-adamantyl (meth) acrylate, 2-isopropyl-2-adamantyl ( The composition according to [6], which is at least one selected from the group consisting of (meth) acrylate and 1- (2-methyl-2-adamantyloxycarbonyl) methyl (meth) acrylate.

[8] The composition according to [6], wherein the monomer that leads to the structural unit represented by the formula (Vc) is 1-ethyl-1-cyclohexyl (meth) acrylate.

［式（ＩＶａ）、式（ＩＶｂ）及び式（ＩＶｃ）中、Ｒ^１は、水素原子又はメチル基を表す。
Ｒ^９は、炭素数１〜４の脂肪族炭化水素基を表す。ｌは、０〜５の整数を表す。
Ｒ^１０及びＲ^１１は、互いに独立に、カルボキシル基、シアノ基又は炭素数１〜４の炭化水素基を表す。ｌ’及びｌ”は、互いに独立に、０〜３の整数を表す。ｌ’及びｌ”が２以上のとき、複数のＲ^１０及びＲ^１１は、それぞれ、互いに同一でも異なってもよい。
Ｚ”は、単結合又は−［ＣＨ_２］_ｋ’−を表し、−［ＣＨ_２］_ｋ’−に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。ｋ’は、１〜１７の整数を表す。］ [9] Any one of [1] to [8], wherein the structural unit (b3) is a structural unit derived from a monomer represented by any one of the formula (IVa), the formula (IVb), or the formula (IVc). The composition according to one.

[In Formula (IVa), Formula (IVb), and Formula (IVc), R ¹ represents a hydrogen atom or a methyl group.
R ⁹ represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. l represents an integer of 0 to 5.
R ¹⁰ and R ¹¹ each independently represent a carboxyl group, a cyano group, or a hydrocarbon group having 1 to 4 carbon atoms. l ′ and l ″ each independently represent an integer of 0 to 3. When l ′ and l ″ are 2 or more, the plurality of R ¹⁰ and R ¹¹ may be the same as or different from each other.
Z ″ represents a single bond or — [CH ₂ ] _{k ′} —, and the methylene group contained in — [CH ₂ ] _{k ′} — may be substituted with an oxygen atom or a carbonyl group. Represents an integer of 1 to 17.]

（式（Ｉ）中、Ｑ^１及びＱ^２は、互いに独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｘ^１は、単結合又は−［ＣＨ_２］_ｋ−を表し、該−［ＣＨ_２］_ｋ−に含まれるメチレン基は酸素原子又はカルボニル基で置換されていてもよく、該−［ＣＨ_２］_ｋ−に含まれる水素原子は直鎖状若しくは分岐状の炭素数１〜４の脂肪族炭化水素基で置換されていてもよい。ｋは、１〜１７の整数を表す。
Ｙ^１は、置換基を有してもよい炭素数３〜３６の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。
Ｚ^＋は、有機カチオンを表す。） [10] The composition according to any one of [1] to [9], wherein the acid generator is an acid generator (A) represented by the formula (I).

(In the formula (I), ^{Q 1} and ^{Q 2} each independently represent a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms.
X ¹ represents a single bond or — [CH ₂ ] _k —, and the methylene group contained in the — [CH ₂ ] _k — may be substituted with an oxygen atom or a carbonyl group, and the — [CH ₂ ] _The hydrogen atom contained in _k- may be substituted with a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms. k represents an integer of 1 to 17.
Y ¹ represents an alicyclic hydrocarbon group having 3 to 36 carbon atoms which may have a substituent, and the methylene group contained in the alicyclic hydrocarbon group is substituted with an oxygen atom or a carbonyl group. May be.
Z ⁺ represents an organic cation. )

［式（Ｙ１）中、環Ｗは、炭素数３〜３６の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。
Ｒ^ａは、水素原子あるいは直鎖状若しくは分岐状の炭素数１〜６の炭化水素基を表す。
Ｒ^ｂは、互いに独立に、ハロゲン原子、直鎖状若しくは分岐状の炭素数１〜１２の脂肪族炭化水素基、炭素数６〜２０の芳香族炭化水素基、炭素数７〜２１のアラルキル基、グリシドキシ基あるいは炭素数２〜４のアシル基を表す。
ｘは、０〜８の整数を表す。ｘが２以上の場合、複数のＲ^ｂは、同一でも異なってもよい。］ [11] The composition according to [10], wherein Y ¹ in the formula (I) is a group represented by the formula (Y1).

[In Formula (Y1), Ring W represents an alicyclic hydrocarbon group having 3 to 36 carbon atoms, and the methylene group contained in the alicyclic hydrocarbon group is substituted with an oxygen atom or a carbonyl group. Also good.
R ^a represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms.
R ^b is independently of each other a halogen atom, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 21 carbon atoms. Represents a glycidoxy group or an acyl group having 2 to 4 carbon atoms.
x represents an integer of 0 to 8. When x is 2 or more, the plurality of R ^b may be the same or different. ]

[12] The composition according to [11], wherein the ring W is at least one ring selected from the group consisting of an adamantane ring, an oxo-adamantane ring and a cyclohexane ring.

[13] The composition according to any one of [10] to [12], wherein the acid generator (A) contains an acid generator in which Z ⁺ is an arylsulfonium cation.

[14] In any one of [1] to [13], the content of the acid generator (A) is 1 to 20 parts by mass with respect to 100 parts by mass of the total amount of the resin (B). The composition as described.

[15] The composition according to any one of [1] to [14], further comprising a nitrogen-containing basic compound.

[16] The composition according to [15], wherein the nitrogen-containing basic compound is diisopropylaniline.

[17] (1) A step of applying the chemically amplified photoresist composition according to any one of [1] to [16] on a substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) A pattern forming method comprising a step of developing the heated composition layer using a developing device.

  According to the chemically amplified photoresist composition of the present invention, it is possible to form a pattern having excellent resolution and line edge roughness and in which pattern collapse does not occur.

The chemically amplified photoresist composition of the present invention (hereinafter sometimes simply referred to as “resist composition”) mainly contains an acid generator (A) and a resin (B).
In the present specification, unless otherwise specified, examples of each substituent are applied to any chemical structural formula having the same substituent while appropriately selecting the number of carbon atoms. Moreover, the thing which can take both a linear or branched includes both. In particular, the “aliphatic hydrocarbon group” refers to a monovalent saturated hydrocarbon group and has a linear or branched aliphatic hydrocarbon group and a cyclic structure including a single ring, a condensed ring or a ring assembly. Includes hydrocarbon groups.
(Meth) acrylic acid represents acrylic acid and / or methacrylic acid.

Resin (B) is at least (b1) a structural unit that generates a carboxyl group by the action of an acid and becomes soluble in an alkaline developer (hereinafter, simply referred to as “structural unit (b1)”),
(B2) Structural unit containing an adamantyl group having at least two —OX ^a groups (X ^a represents a group capable of leaving by the action of an acid) (hereinafter simply referred to as “structural unit (b2)”) And (b3) a structural unit derived from a monomer having a lactone ring (hereinafter sometimes simply referred to as “structural unit (b3)”).
Any of these structural units (b1), (b2), and (b3) may be included alone, or two or more thereof may be included.
Further, the resin (B) may be one kind, or a combination of two or more kinds of these structural units (b1), (b2), (b3) and the like having different amounts or kinds.

（式（Ｖａ）、式（Ｖｂ）、式（Ｖｃ）及び式（Ｖｄ）において、Ｒ^１は、水素原子又はメチル基を表す。
Ｒ^２は、炭素数１〜８の脂肪族炭化水素基あるいは炭素数３〜１０の脂環式炭化水素基を表す。
Ｒ^３は、メチル基を表す。
Ｒ^４及びＲ^５は、互いに独立に、水素原子又は炭素数１〜８のヘテロ原子を含んでもよい１価の炭化水素基を表すか、あるいはＲ^４とＲ^５とが連結して炭素数３〜８の環を形成していてもよい。また、Ｒ^４とＲ^５とは、Ｒ^４が結合する炭素原子とＲ^５が結合する炭素原子との間で二重結合を形成してもよい。
ｎは、０〜１４の整数を表す。ｎ’は、０〜３の整数を表す。ｍは、１〜３の整数を表す。
Ｚ”は、互いに独立に、単結合又は、−［ＣＨ_２］_ｋ’−を表し、−［ＣＨ_２］_ｋ’−に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。ｋ’は、１〜１７の整数を表す。］ (B1) The structural unit that generates a carboxyl group by the action of an acid and becomes soluble in an alkaline developer is, for example, a structure represented by the formula (Va), the formula (Vb), the formula (Vc), or the formula (Vd). Examples thereof include units, preferably structural units represented by formula (Va) and formula (Vc).

(In Formula (Va), Formula (Vb), Formula (Vc), and Formula (Vd), R ¹ represents a hydrogen atom or a methyl group.
R ² represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 10 carbon atoms.
R ³ represents a methyl group.
R ⁴ and R ⁵ each independently represent a hydrogen atom or a monovalent hydrocarbon group that may contain a hetero atom having 1 to 8 carbon atoms, or R ⁴ and R ⁵ are linked to form a carbon atom having 3 carbon atoms. -8 rings may be formed. R ⁴ and R ⁵ may form a double bond between the carbon atom to which R ⁴ is bonded and the carbon atom to which R ⁵ is bonded.
n represents an integer of 0 to 14. n ′ represents an integer of 0 to 3. m represents an integer of 1 to 3.
Z ″ represents, independently of each other, a single bond or — [CH ₂ ] _{k ′} —, and the methylene group contained in — [CH ₂ ] _{k ′} — may be substituted with an oxygen atom or a carbonyl group. K ′ represents an integer of 1 to 17.]

などが挙げられる。
ヘテロ原子を含んでもよい１価の炭化水素基としては、複素環基が挙げられ、例えば、オキセタニル基、テトラヒドロフラニル基、テトラヒドロピラニル基、フリル基、チエニル基、プロリルピリジニル基、インドリル基、ベンゾジオキソリル基等が挙げられる。
Ｒ^４とＲ^５とが形成する環としては、上述した脂環式炭化水素、複素環等が挙げられる。 Here, as the aliphatic hydrocarbon group, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, Examples thereof include alkyl groups such as heptyl group, octyl group and 2-ethylhexyl group, groups such as methylcyclohexyl group and cyclohexylmethyl group.
Examples of the alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, a norbornyl group, a 1-adamantyl group, and a 2-adamantyl group. , Isobornyl group,

Etc.
Examples of the monovalent hydrocarbon group which may contain a hetero atom include a heterocyclic group, such as oxetanyl group, tetrahydrofuranyl group, tetrahydropyranyl group, furyl group, thienyl group, prolylpyridinyl group, indolyl group. Group, benzodioxolyl group and the like.
Examples of the ring formed by R ⁴ and R ⁵ include the above-described alicyclic hydrocarbons and heterocyclic rings.

The group in which the methylene group contained in — [CH ₂ ] _k — is substituted is a group in which the methylene group is substituted with an oxygen atom or a carbonyl group, that is, one oxygen atom, two oxygen atoms, and a carbonyl group , Two carbonyl groups, one oxygen atom and two carbonyl groups, one oxygen atom and three carbonyl groups, two oxygen atoms and one carbonyl group, two oxygen atoms and a carbonyl group Various things such as two are included. For example, —CO—O—X ¹¹ — (ring group such as an adamantyl group from (Va) to (Vd): hereinafter referred to as “Ad”), —O—CO—X ¹¹ — (Ad), —O—X ^{11 - (Ad), - X} 11 -O- (Ad), - X 11 -CO-O- (Ad), - X 11 -O-CO- (Ad), - X 11 -O-X 12 - ( Ad), —CO—O—X ¹¹ —CO—O— (Ad), —CO—O—X ¹¹ —O— (Ad), and the like. Among them, preferred is ^{-CO-O-X 11 - (} Ad), - X 11 is -O- (Ad) and ^{-X 11 -CO-O- (Ad)} , more preferably ^{-CO-O-X 11} — (Ad) and —X ¹¹ —CO—O— (Ad), more preferably —CO—O—X ¹¹ — (Ad).
Here, X ¹¹ and X ¹² each independently represent a linear or branched alkylene group having 1 to 15 carbon atoms (also referred to as alkanediyl group). However, in the group in which the methylene group contained in the alkylene group is substituted, the number of atoms constituting the main chain of each of the above groups is 1 to 17, which is the same as k ′.

  Examples of the monomer for deriving the structural unit represented by the formula (Va) include the following.

  Among them, since the sensitivity of the resulting resist composition tends to be excellent and the heat resistance tends to be excellent, monomers that lead to the structural unit represented by the formula (Va) are 2-methyl-2-adamantyl acrylate, 2-methyl- 2-adamantyl methacrylate, 2-ethyl-2-adamantyl acrylate, 2-ethyl-2-adamantyl methacrylate, 2-isopropyl-2-adamantyl acrylate, 2-isopropyl-2-adamantyl methacrylate, 1- (methyl-2-adamantyloxy It is preferably at least one selected from the group consisting of carbonyl) methyl acrylate and 1- (methyl-2-adamantyloxycarbonyl) methyl methacrylate.

Examples of the monomer for deriving the structural unit represented by the formula (Vb) include the following.

Examples of the monomer for deriving the structural unit represented by the formula (Vc) include the following.

  Among them, since the sensitivity of the resulting resist composition tends to be excellent and the heat resistance tends to be excellent, the monomer that leads to the structural unit represented by the formula (Vc) is 1-ethyl-1-cyclohexyl acrylate or 1-ethyl- It is preferable that it is 1-cyclohexyl methacrylate.

  Examples of the monomer for deriving the structural unit represented by the formula (Vd) include the following.

  As the structural unit (b1), a structural unit represented by the formula (Va) or the formula (Vc) is particularly preferable.

(B2) -OX ^a group (X ^a represents. A group which leaves by the action of an acid) Examples of the structural unit containing at least two having adamantyl group, 1-adamantyl, as 2-adamantyl ester And a structure in which a part of such a polycyclic ester is substituted with two hydroxyl groups.

Here, the X ^a in (b2), upon exposure to a layer consisting of a chemically amplified photoresist composition comprising a resin (B) and acid generator and (A), generated from the acid generator (A) It means a group contained in the structural unit represented by the formula (III) that is eliminated by the action of the acid, and at the same time, ^a hydroxyl group is generated by elimination of Xa contained in the structural unit represented by the formula (III).
Therefore, in the formation of a pattern using the chemically amplified photoresist composition of the present invention containing a resin containing such a structural unit (b2), the resist composition coated on the substrate is selectively used. When exposed, the solubility of the exposed area in an alkaline developer increases, and development can be performed with high resolution.

The X ^a included in the structural unit (b2), a group to bond by reacting with a hydroxyl group, and may be a group capable of leaving by the acid, for example, tertiary aliphatic hydrocarbon group or contains it Groups (hereinafter sometimes referred to as “tertiary aliphatic hydrocarbon group-containing group”), alkoxyalkyl groups, and the like.

  Here, the “tertiary aliphatic hydrocarbon group” refers to an aliphatic hydrocarbon group having a tertiary carbon atom. The “tertiary aliphatic hydrocarbon group-containing group” refers to a group containing a tertiary aliphatic hydrocarbon group in its structure. The tertiary aliphatic hydrocarbon group-containing group may be composed of a tertiary aliphatic hydrocarbon group and an atom or group other than the tertiary aliphatic hydrocarbon group. In addition, examples of the “other atom or group” include an oxygen atom, a carbonyl group, a carbonyloxy group, an alkylene group, or a combination thereof.

The tertiary aliphatic hydrocarbon group or the group containing it may be either one having no cyclic structure or one having a cyclic structure.
The tertiary aliphatic hydrocarbon group-containing group having no cyclic structure is a group containing a branched tertiary aliphatic hydrocarbon group in the structure and having no cyclic structure.

［式（IIIａ）中、Ｒ^２１、Ｒ^２２及びＲ^２３は、互いに独立に、直鎖状若しくは分岐状の炭素数１〜５の脂肪族炭化水素基を表す。］ Examples of the branched tertiary aliphatic hydrocarbon group include a group represented by the formula (IIIa).

[In Formula (IIIa), R ²¹ , R ²² and R ²³ each independently represent a linear or branched aliphatic hydrocarbon group having 1 to 5 carbon atoms. ]

Examples of the aliphatic hydrocarbon group include those described above, and among them, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, and a tert-butyl group are preferable. More preferably, they are a methyl group, an ethyl group, an n-propyl group, and an isopropyl group.
The total carbon number of the group represented by the formula (IIIa) is preferably 4 to 7, more preferably 4 to 6, and still more preferably 4 to 5.
Specific examples of the group represented by the formula (IIIa) include a tert-butyl group and a tert-amyl group, and a tert-butyl group is preferable.

As the tertiary aliphatic hydrocarbon group-containing group having no cyclic structure, the above-described branched tertiary aliphatic hydrocarbon group; the above-described branched tertiary aliphatic hydrocarbon group is linear Or a chained aliphatic hydrocarbon group containing a tertiary aliphatic hydrocarbon group bonded to a branched alkylene group; the branched tertiary aliphatic hydrocarbon described above as the tertiary aliphatic hydrocarbon group A tertiary alkyloxycarbonyl group having a group; a tertiary alkyloxycarbonylalkyl group having a branched tertiary alkyl group as described above as a tertiary alkyl group.
Here, the alkylene group in the tertiary aliphatic hydrocarbon group-containing group is preferably an alkylene group having 1 to 5 carbon atoms, more preferably an alkylene group having 1 to 4 carbon atoms, and an alkylene group having 1 to 2 carbon atoms. Is more preferable.

［式（IIIｂ）中、Ｒ^２１、Ｒ^２２及びＲ^２３は、式（IIIａ）におけるものと同じものを表す。］ Examples of the tertiary alkyloxycarbonyl group include a group represented by the formula (IIIb).

[In formula (IIIb), R ²¹ , R ²² and R ²³ represent the same as those in formula (IIIa). ]

  As the tertiary alkyloxycarbonyl group, a tert-butyloxycarbonyl group and a tert-amyloxycarbonyl group are preferable.

［式（IIIｃ）中、Ｒ^２１、Ｒ^２２及びＲ^２３は、式（IIIａ）におけるものと同じものを表す。ｆは１〜３の整数を表す。］
中でも、ｆは、１または２が好ましい。 Examples of the tertiary alkyloxycarbonylalkyl group include a group represented by the formula (IIIc).

[In Formula (IIIc), R ²¹ , R ²² and R ²³ represent the same as those in Formula (IIIa). f represents an integer of 1 to 3. ]
Among these, f is preferably 1 or 2.

As the tertiary alkyloxycarbonylalkyl group, a tert-butyloxycarbonylmethyl group and a tert-butyloxycarbonylethyl group are preferable.
Among them, the tertiary aliphatic hydrocarbon group-containing group having no cyclic structure is preferably a tertiary alkyloxycarbonyl group or a tertiary alkyloxycarbonylalkyl group, more preferably a tertiary alkyloxycarbonyl group, A tert-butyloxycarbonyl group is more preferred.

The tertiary aliphatic hydrocarbon group-containing group having a cyclic structure is a group having a tertiary carbon atom and a cyclic structure in the structure.
In the tertiary aliphatic hydrocarbon group-containing group having a cyclic structure, the cyclic structure preferably has 4 to 12 carbon atoms, more preferably 5 to 10 carbon atoms, and more preferably 6 to 10 carbon atoms. More preferably it is.
Examples of the cyclic structure include groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane. Preferable examples include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

Examples of the tertiary aliphatic hydrocarbon group-containing group having a cyclic structure include a group having the following group (1) or (2) as a tertiary aliphatic hydrocarbon group.
(1) a group in which a linear or branched aliphatic hydrocarbon group is bonded to a carbon atom constituting a ring of an alicyclic hydrocarbon group, and the carbon atom becomes a tertiary carbon atom,
(2) A group in which an alkylene group having a tertiary carbon atom (branched alkylene group) is bonded to the carbon atom constituting the ring of the alicyclic hydrocarbon group.

The number of carbon atoms of the linear or branched aliphatic hydrocarbon group in the group (1) is preferably 1 to 5, more preferably 1 to 4, and preferably 1 to 3. Further preferred.
Specific examples of the group (1) include 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, 1-methyl-1-cycloalkyl group, 1-ethyl-1-cycloalkyl group and the like. Can be mentioned.

  In the above (2), the alicyclic hydrocarbon group to which the branched alkylene group is bonded is a fluorine atom or a fluorinated aliphatic hydrocarbon group having 1 to 5 carbon atoms in which the hydrogen atom is substituted with a fluorine atom or a fluorine atom. May be substituted. The methylene group contained in the alicyclic hydrocarbon group represents an oxygen atom, a sulfur atom or a carbonyl group.

［式（IIIｄ）中、Ｒ^２４は、置換されていてもよい炭素数３〜３６の脂環式炭化水素基を表す。該脂環式炭化水素基の水素原子は、フッ素原子、フッ素原子で置換された炭素数１〜５のフッ素化アルキル基で置換されていてもよく、該脂環式炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基を表す。
Ｒ^２５及びＲ^２６は、互いに独立に、直鎖状または分岐状の炭素数１〜１５の脂肪族炭化水素基を表し、該脂肪族炭化水素基としては、前記式（IIIａ）におけるＲ^２１〜Ｒ^２３における脂肪族炭化水素基と同様のものが挙げられる。]
ここで、フッ素化アルキル基及びフッ素化脂肪族炭化水素基としては、１以上の水素原子がフッ素原子で置換されたアルキル基又は脂肪族炭化水素基が例示され、例えば、フルオロメチル基、ジフルオロメチル基、ペルフルオロメチル基、ペルフルオロエチル基、ペルフルオロプロピル基、ペルフルオロイソプロピル基、ペルフルオロブチル基、ペルフルオロｓｅｃ−ブチル基、ペルフルオロｔｅｒｔ−ブチル基、ペルフルオロペンチル基等が挙げられる。 Specific examples of the group (2) include a group represented by the formula (IIId).

[In the formula (IIId), R ²⁴ represents an optionally substituted alicyclic hydrocarbon group having 3 to 36 carbon atoms. The hydrogen atom of the alicyclic hydrocarbon group may be substituted with a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and methylene contained in the alicyclic hydrocarbon group The group represents an oxygen atom or a carbonyl group.
R ²⁵ and R ²⁶ each independently represent a linear or branched aliphatic hydrocarbon group having 1 to 15 carbon atoms, and examples of the aliphatic hydrocarbon group include R ²¹ to R ²¹ in the formula (IIIa). those similar to the aliphatic hydrocarbon group for R ²³ can be mentioned. ]
Here, examples of the fluorinated alkyl group and the fluorinated aliphatic hydrocarbon group include an alkyl group or an aliphatic hydrocarbon group in which one or more hydrogen atoms are substituted with a fluorine atom, and examples thereof include a fluoromethyl group and a difluoromethyl group. Group, perfluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluoro sec-butyl group, perfluoro tert-butyl group, perfluoropentyl group and the like.

［式（IIIｅ）中、Ｒ^４１は、直鎖状、分岐状若しくは環状の炭素数１〜１５の脂肪族炭化水素基を表す。該脂肪族炭化水素基は、オキソ基が置換されていてもよい。
Ｒ^４２は、直鎖状若しくは分岐状の炭素数１〜５のアルキレン基を表す。］ Examples of the alkoxyalkyl group include groups represented by formulas (IIIe) and (IIIf), and the group represented by (IIIf) is particularly preferable.

[In the formula (IIIe), R ⁴¹ represents a linear, branched or cyclic aliphatic hydrocarbon group having 1 to 15 carbon atoms. The aliphatic hydrocarbon group may be substituted with an oxo group.
^R42 represents a linear or branched alkylene group having 1 to 5 carbon atoms. ]

When R ⁴¹ is a linear or branched aliphatic hydrocarbon group, the carbon number is preferably 1 to 5. Specific examples include the same aliphatic hydrocarbon groups as described above, preferably a methyl group and an ethyl group, and more preferably an ethyl group.
When R ⁴¹ is cyclic, the carbon number thereof is preferably 4 to 15, more preferably 4 to 12, and still more preferably 5 to 10. For example, groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane and tetracycloalkane, and in these groups, the hydrogen atom is a fluorine atom or a carbon number of 1 to 5 And a group substituted with a fluorinated aliphatic hydrocarbon group. Specific examples include monocycloalkanes such as cyclopentane and cyclohexane, groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.

The number of carbon atoms of the alkylene group for R ⁴² is preferably 1 to 3, more preferably 1 to 2.

［式（IIIｆ）中、Ｒ^４１は、式（IIIｅ）におけるもの同じものを表す。Ｒ^４３及びＲ^４４は、互いに独立に、水素原子あるいは直鎖状若しくは分岐状の炭素数１〜１５の脂肪族炭化水素基を表す。]

[In formula (IIIf), R ⁴¹ represents the same as in formula (IIIe). R ⁴³ and R ⁴⁴ each independently represent a hydrogen atom or a linear or branched aliphatic hydrocarbon group having 1 to 15 carbon atoms. ]

In R ⁴³ and R ⁴⁴ , the aliphatic hydrocarbon group preferably has 1 to 15 carbon atoms, and the aliphatic hydrocarbon group is preferably an ethyl group and a methyl group, and more preferably a methyl group. Among these, it is more preferable that one of R ⁴³ and R ⁴⁴ is a hydrogen atom and the other is a methyl group.

中でも、第三級脂肪族炭化水素基含有基が好ましく、式（IIIｂ）で表される基がより好ましく、ｔｅｒｔ−ブチルオキシカルボニル基がより好ましい。 Specific examples of X ^a, for example, the following formula (III-1) ~ formula (III-28) are exemplified, a group preferably represented by formula (III-3) ~ formula (III-8) Can be mentioned. These groups represented by the formula (III-3) to the formula (III-8) are linear, branched or cyclic tertiary aliphatic hydrocarbon groups having 4 to 12 carbon atoms having an ester bond. Yes, it is preferably a branched tertiary aliphatic hydrocarbon group having 4 to 7 carbon atoms having an ester bond.

Among them, a tertiary aliphatic hydrocarbon group-containing group is preferable, a group represented by the formula (IIIb) is more preferable, and a tert-butyloxycarbonyl group is more preferable.

［式（III）中、Ｒ^１は、水素原子又はメチル基を表す。
Ｒ^６及びＲ^７は、互いに独立に、水素原子、メチル基、水酸基又は−ＯＸ^ａ基を表し、ただし、Ｒ^６及びＲ^７の少なくともいずれか一方は−ＯＸ^ａ基を表す。
Ｒ^８は、メチル基を表す。
Ｘ^ａは、酸の作用により脱離し得る基を表す。
Ｚ”は、単結合又は、−［ＣＨ_２］_ｋ’−を表し、−［ＣＨ_２］_ｋ’−に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。ｋ’は、１〜１７の整数を表す。
ｎ’は、０〜１０の整数を表す。］ Examples of the structural unit (b2) include a structural unit represented by the formula (III).

[In Formula (III), R ¹ represents a hydrogen atom or a methyl group.
R ⁶ and R ⁷ each independently represent ^a hydrogen atom, a methyl group, a hydroxyl group or an —OX ^a group, provided that at least one of R ⁶ and R ⁷ represents an —OX ^a group.
R ⁸ represents a methyl group.
X ^a represents a group which leaves by the action of an acid.
Z ″ represents a single bond or — [CH ₂ ] _{k ′} —, and the methylene group contained in — [CH ₂ ] _{k ′} — may be substituted with an oxygen atom or a carbonyl group. , Represents an integer of 1 to 17.
n ′ represents an integer of 0 to 10. ]

Here, examples of ^Xa include groups represented by the above formulas (III-1) to (III-28).
Examples of the monomer for deriving the structural unit represented by the formula (III) include the following.

Specific examples of X ^a in the structural unit represented by formula (III), the formula (III-1) ~ formula (III-28) are mentioned.

Among them, the structural unit represented by the formula (III) includes 3,5-dihydroxy-1-adamantyl acrylate, 3,5-dihydroxy-1-adamantyl methacrylate, 1- (
In any of 3,5-dihydroxy-1-adamantyloxycarbonyl) methyl acrylate and 1- (3,5-dihydroxy-1-adamantyloxycarbonyl) methyl methacrylate, an —OX ^a group (X ^a is formed by the action of an acid). Represents a group capable of leaving.), That is, a linear, branched or cyclic tertiary aliphatic hydrocarbon group having 4 to 12 carbon atoms in which the hydrogen atom of the hydroxyl group has an ester bond. Those that are structural units derived from substituted monomers are preferred. Among these structural units, those in which ^Xa is the formula (III-1), formula (III-3) or formula (III-5) are more preferable. In a chemically amplified photoresist composition using a resin containing such a structural unit, high resolution performance can be exhibited.

［式（IIIａ'）中、Ｒ^１、Ｒ^８、Ｚ”及びｎ’は、式（III)におけるものと同じである。
Ｒ^６及びＲ^７は、互いに独立に、水素原子、メチル基又は水酸基を表し、ただし、Ｒ^６及びＲ^７の少なくともいずれか一方は水酸基である。］
式（IIIａ'）で表される構造単位を導くモノマーとしては、以下の式（III’）で表される構造単位を導くモノマーのうち、アダマンチル基において２つ以上の水酸基を有する
化合物が例示される。 The structural unit (b2) containing an adamantyl group having at least two —OX ^a groups (X ^a represents a group capable of leaving by the action of an acid) is produced by a method known in the art. be able to. That is, X ^a is reacted (protected) with ^a monomer that leads to a structural unit containing an adamantyl group having at least two hydroxyl groups represented by the formula (IIIa ′), or X is added to a hydroxyl group as a raw material for synthesizing the monomer. ^{and a} method using a compound to which ^a is bonded. Or it can manufacture according to the manufacturing method of the monomer which leads the structural unit of the formula (a0) described in Unexamined-Japanese-Patent No. 2007-146613.

[In Formula (IIIa ′), R ¹ , R ⁸ , Z ″ and n ′ are the same as those in Formula (III).
R ⁶ and R ⁷ each independently represent a hydrogen atom, a methyl group or a hydroxyl group, provided that at least one of R ⁶ and R ⁷ is a hydroxyl group. ]
Examples of the monomer that leads to the structural unit represented by the formula (IIIa ′) include compounds having two or more hydroxyl groups in the adamantyl group among the monomers that lead to the structural unit represented by the following formula (III ′). The

  (B3) The structural unit derived from a monomer having a lactone ring is a structural unit derived from a monomer having a lactone structure in the side chain (however, different from the structural unit represented by the formula (I)). Specific examples include structural units derived from a compound having a β-butyrolactone structure, a compound having a γ-butyrolactone structure, a compound having a lactone structure added to a cycloalkyl skeleton or a norbornane skeleton, and the like.

［式（ＩＶａ）、式（ＩＶｂ）及び式（ＩＶｃ）中、Ｒ^１は、水素原子又はメチル基を表す。
Ｒ^９は、炭素数１〜４の脂肪族炭化水素基を表す。ｌは、０〜５の整数を表す。
Ｒ^１０及びＲ^１１は、互いに独立に、カルボキシル基、シアノ基又は炭素数１〜４の炭化水素基を表す。ｌ’及びｌ”は、互いに独立に、０〜３の整数を表す。ｌ’及びｌ”が２以上のとき、複数のＲ^１０及びＲ^１１は、それぞれ、互いに同一でも異なってもよい。
Ｚ”は、単結合又は−［ＣＨ_２］_ｋ’−を表し、−［ＣＨ_２］_ｋ’−に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。ｋ’は、１〜１７の整数を表す。］ Examples of the structural unit (b3) include structural units represented by any one of the formula (IVa), the formula (IVb), and the formula (IVc).

[In Formula (IVa), Formula (IVb), and Formula (IVc), R ¹ represents a hydrogen atom or a methyl group.
R ⁹ represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. l represents an integer of 0 to 5.
R ¹⁰ and R ¹¹ each independently represent a carboxyl group, a cyano group, or a hydrocarbon group having 1 to 4 carbon atoms. l ′ and l ″ each independently represent an integer of 0 to 3. When l ′ and l ″ are 2 or more, the plurality of R ¹⁰ and R ¹¹ may be the same as or different from each other.
Z ″ represents a single bond or — [CH ₂ ] _{k ′} —, and the methylene group contained in — [CH ₂ ] _{k ′} — may be substituted with an oxygen atom or a carbonyl group. Represents an integer of 1 to 17.]

Examples of the monomer for deriving the structural unit represented by the formula (IVa) include the following.

Examples of the monomer for deriving the structural unit represented by the formula (IVb) include the following.

Examples of the monomer for deriving the structural unit represented by the formula (IVc) include the following.

Among them, (meth) acrylic acid hexahydro-2-oxo-3,5-methano-2H-cyclopenta [b] furan-6-yl, (meth) acrylic acid tetrahydro-2-oxo-3-furyl, (meth) acrylic The acid 2- (5-oxo-4-oxatricyclo [4.2.1.0 ^3.7 ] nonan-2-yloxy) -2-oxoethyl and the like are preferable. A resist composition using a resin containing these structural units can improve adhesion to a substrate.

  Furthermore, the resin (B) may contain one or more structural units (b4) having a hydroxyl group (excluding the OH group contained in the carboxyl group) in the side chain.

  (B4) Specific examples of the structural unit having a hydroxyl group (excluding the OH group contained in the carboxyl group) in the side chain include cyclic esters represented by various esters of carboxylic acid such as cyclopentyl ester and cyclohexyl ester. Examples include alkylesters; a structure in which a part of a polycyclic ester such as norbornyl ester, 1-adamantyl ester, and 2-adamantyl ester is substituted with a hydroxyl group.

［式（III’）中、Ｒ^１、Ｒ^８、Ｚ”及びｎ’は、式（III）におけるものと同義である。
Ｒ^６’及びＲ^７’は、互いに独立に、水素原子、メチル基又は水酸基を表す。］ Examples of such a structural unit (b4) include a structural unit represented by the formula (III ′).

[In formula (III ′), R ¹ , R ⁸ , Z ″ and n ′ have the same meaning as in formula (III).
R ^{6 ′} and R ^{7 ′} each independently represent a hydrogen atom, a methyl group or a hydroxyl group. ]

Examples of the monomer for deriving the structural unit represented by the formula (III ′) include the following.

In each of the above monomers, a monomer in which a hydrogen atom of one hydroxy group is substituted with ^a —OX ^a group (X ^a represents a group capable of leaving by the action of an acid) in the structural unit (b2). There may be.

  Among them, 3-hydroxy-1-adamantyl acrylate, 3-hydroxy-1-adamantyl methacrylate, 3,5-dihydroxy-1-adamantyl acrylate, 3,5-dihydroxy-1-adamantyl methacrylate, 1- (3-hydroxy-1 -Adamantyloxycarbonyl) methyl acrylate, 1- (3-hydroxy-1-adamantyloxycarbonyl) methyl methacrylate, 1- (3,5-dihydroxy-1-adamantyloxycarbonyl) methyl acrylate, 1- (3,5-dihydroxy -1-adamantyloxycarbonyl) methyl methacrylate and the like, and preferably 3-hydroxy-1-adamantyl acrylate, 3-hydroxy-1-adamantyl methacrylate, 3,5-dihydroxy-1-adama Chill acrylate and 3,5-dihydroxy-1-adamantyl methacrylate are more preferred. By using a resin containing these structural units, a resist composition exhibiting high resolution performance can be provided.

〔式（VI）中、Ｒ^１は、水素原子又はメチル基を表す。
Ａｒは、単結合又は炭素数１〜３６の炭化水素基を表し、該炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。該炭化水素基に含まれる水素原子は、フッ素原子に置換されていてもよい。
Ｒ^ｂは、２価の炭素数４〜３６の脂環式炭化水素基を表す。
Ｒ^ｃは、水素原子あるいは直鎖状若しくは分岐状の炭素数１〜６の脂肪族炭化水素基を表す。
炭素数１〜３６の炭化水素基に含まれるメチレン基は、任意に、酸素原子又はカルボニル基で置換されていてもよく、結合する水素原子の一部又はすべてがフッ素原子に置換された炭素数１〜３０の直鎖状若しくは分岐状の炭化水素基であるか又は１個以上の水素原子がフッ素原子に置換され、アルキル基を置換基として有していてもよい炭素数３〜３０の単環又は多環式炭化水素基を表す。
ａは０〜５の整数を表す。〕 Furthermore, the resin (B) may further contain (b5) a structural unit represented by the formula (VI).

[In Formula (VI), R ¹ represents a hydrogen atom or a methyl group.
Ar represents a single bond or a C1-C36 hydrocarbon group, and the methylene group contained in the hydrocarbon group may be substituted with an oxygen atom or a carbonyl group. A hydrogen atom contained in the hydrocarbon group may be substituted with a fluorine atom.
R ^b represents a divalent alicyclic hydrocarbon group having 4 to 36 carbon atoms.
R ^c represents a hydrogen atom or a linear or branched aliphatic hydrocarbon group having 1 to 6 carbon atoms.
The methylene group contained in the hydrocarbon group having 1 to 36 carbon atoms may be optionally substituted with an oxygen atom or a carbonyl group, and the number of carbon atoms in which some or all of the bonded hydrogen atoms are substituted with fluorine atoms. A straight-chain or branched hydrocarbon group having 1 to 30 carbon atoms, or one or more hydrogen atoms may be substituted with fluorine atoms, and an alkyl group may be used as a substituent. Represents a ring or polycyclic hydrocarbon group.
a represents an integer of 0 to 5. ]

  Here, the hydrocarbon group includes linear, branched or cyclic hydrocarbons, aromatic hydrocarbons, and combinations thereof. That is, an alkyl group, a cycloalkyl group, an alkylcycloalkyl group, an aryl group, an aralkyl group, an alkylaryl group, and combinations thereof are included.

Examples of the monomer that leads to the structural unit represented by the formula (VI) include the following monomers.

Among these, Ar is preferably a monocyclic or polycyclic hydrocarbon group in which one or more hydrogen atoms are substituted with fluorine atoms. For example, (meth) acrylic acid 5- (3,3,3-trifluoro-2-hydroxy-2- [trifluoromethyl] propyl) bicyclo [2.2.1] hept-2-yl, (meth) acrylic Acid 6- (3,3,3-trifluoro-2-hydroxy-2- [trifluoromethyl] propyl) bicyclo [2.2.1] hept-2-yl, 4,4-bis (meth) acrylic acid A resin having a structural unit derived from (trifluoromethyl) -3-oxatricyclo [4.2.1.0 ^2,5 ] nonyl is more preferable because it provides a chemically amplified resist composition exhibiting high resolution. .

Furthermore, each resin constituting the resin (B) may have one or more structural units (b6) other than the structural units (b1) to (b5).
Examples of such a structural unit (b6) include a structural unit derived from 2-norbornene. The structural unit derived from 2-norbornene is formed by opening a double bond of the norbornene structure and can be represented by the formula (d). In addition, 2-norbornene is introduced into the main chain at the time of polymerization, for example, by radical polymerization using, in addition to the corresponding 2-norbornene, an aliphatic unsaturated dicarboxylic acid anhydride such as maleic anhydride or itaconic anhydride. May be. The structural unit derived from maleic anhydride and itaconic anhydride is formed by opening a double bond of maleic anhydride and itaconic anhydride, and can be represented by formulas (e) and (f), respectively.

ここで、式（ｄ）中のＲ^２５及びＲ^２６は、互いに独立に、水素原子、炭素数１〜３の脂肪族炭化水素基、カルボキシル基、シアノ基もしくは−ＣＯＯＵ（Ｕはアルコール残基である）を表すか、あるいは、Ｒ^２５及びＲ^２６が、互いに結合して、−Ｃ（＝Ｏ）ＯＣ（＝Ｏ）−で表されるカルボン酸無水物残基を形成する。
前記−ＣＯＯＵは、カルボキシル基がエステルとなったものであり、Ｕに相当するアルコール残基としては、例えば、置換されていてもよい炭素数１〜８の脂肪族炭化水素基、２−オキソオキソラン−３−イル基又は２−オキソオキソラン−４−イル基などを挙げることができる。ここで、脂肪族炭化水素基の置換基として、水酸基や炭素数４〜３６の脂環式炭化水素残基などが結合していてもよい。
Ｒ^２５及びＲ^２６における脂肪族炭化水素基としては、例えば、メチル基、エチル基、プロピル基などが挙げられ、水酸基が結合した脂肪族炭化水素基としては、ヒドロキシメチル基、２−ヒドロキシエチル基などが挙げられる。

Here, R ²⁵ and R ²⁶ in the formula (d) are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 3 carbon atoms, a carboxyl group, a cyano group, or —COOU (U is an alcohol residue) R ²⁵ and R ²⁶ are bonded to each other to form a carboxylic acid anhydride residue represented by —C (═O) OC (═O) —.
The —COOU has a carboxyl group as an ester, and examples of the alcohol residue corresponding to U include an optionally substituted aliphatic hydrocarbon group having 1 to 8 carbon atoms and 2-oxooxo. A lan-3-yl group or a 2-oxooxolan-4-yl group can be exemplified. Here, as a substituent of the aliphatic hydrocarbon group, a hydroxyl group or an alicyclic hydrocarbon residue having 4 to 36 carbon atoms may be bonded.
Examples of the aliphatic hydrocarbon group for R ²⁵ and R ²⁶ include a methyl group, an ethyl group, and a propyl group. Examples of the aliphatic hydrocarbon group to which a hydroxyl group is bonded include a hydroxymethyl group and a 2-hydroxyethyl group. Etc.

  Specific examples of the monomer that leads to the norbornene structure represented by the formula (d) include, for example, 2-norbornene, 2-hydroxy-5-norbornene, 5-norbornene-2-carboxylic acid, 5-norbornene-2-carboxylic acid Examples include methyl, 2-hydroxy-1-ethyl 5-norbornene-2-carboxylate, 5-norbornene-2-methanol, 5-norbornene-2,3-dicarboxylic acid anhydride, and the like.

  In addition, about U of —COOU in the formula (d), a norbornene structure is used as long as it is an acid-labile group such as an alicyclic ester in which the carbon atom bonded to the oxygen side of the carboxyl group is a quaternary carbon atom. Is a structural unit having an acid labile group. Examples of the monomer containing a norbornene structure and an acid labile group include, for example, 5-norbornene-2-carboxylic acid-t-butyl, 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, 5- 1-methylcyclohexyl norbornene-2-carboxylate, 2-methyl-2-adamantyl 5-norbornene-2-carboxylate, 2-ethyl-2-adamantyl 5-norbornene-2-carboxylate, 5-norbornene-2-carboxyl Acid 1- (4-methylcyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1- (4-hydroxycyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1-methyl-1 -(4-oxocyclohexyl) ethyl, 5-norbornene-2-carboxylic acid 1- (1-adap Pentyl) -1-methylethyl and the like.

The weight average molecular weight of the resin (B) is preferably 1,000 or more and 100,000 or less, more preferably 2,000 or more and 50,000 or less, and further preferably 2,500 or more and 30,000 or less. .
In addition, a weight average molecular weight is the value measured by GPC method, for example, Specifically, what was measured on the measurement conditions described in the Example, etc. are mentioned.

［式（Ｉ）中、Ｑ^１及びＱ^２は、互いに独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｘ^１は、単結合又は−［ＣＨ_２］_ｋ−を表し、該−［ＣＨ_２］_ｋ−に含まれるメチレン基は酸素原子及び／又はカルボニル基で置換されていてもよく、該−［ＣＨ_２］_ｋ−に含まれる水素原子は直鎖状若しくは分岐状の炭素数１〜４の脂肪族炭化水素基で置換されていてもよい。ｋは、１〜１７の整数を表す。
Ｙ^１は、置換基を有してもよい炭素数３〜３６の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。
Ｚ^＋は、有機カチオンを表す。］ Examples of the acid generator (A) include an acid generator represented by the formula (I).

[In Formula (I), Q < ¹ > and Q < ² > represent a fluorine atom or a C1-C6 perfluoroalkyl group mutually independently.
X ¹ represents a single bond or — [CH ₂ ] _k —, and the methylene group contained in — [CH ₂ ] _k — may be substituted with an oxygen atom and / or a carbonyl group. ₂ ] The hydrogen atom contained in _k- may be substituted with a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms. k represents an integer of 1 to 17.
Y ¹ represents an alicyclic hydrocarbon group having 3 to 36 carbon atoms which may have a substituent, and the methylene group contained in the alicyclic hydrocarbon group is substituted with an oxygen atom or a carbonyl group. May be.
Z ⁺ represents an organic cation. ]

  Examples of perfluoroalkyl groups include perfluoromethyl group, perfluoroethyl group, perfluoro-n-propyl group, perfluoroisopropyl group, perfluoro-n-butyl group, perfluoro-sec-butyl group, perfluoro-tert-butyl group, perfluoro-n- A pentyl group, a perfluoro-n-hexyl group, etc. are mentioned.

Examples of — [CH ₂ ] _k — include, for example, a methylene group, a dimethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, a heptamethylene group, an octamethylene group, a nonamethylene group, a decamethylene group, and an undecamethylene group. Group, dodecamethylene group, tridecamethylene group, tetradecamethylene group, pentadecamethylene group, hexadecamethylene group, heptacamethylene group, ethylene group, propylene group, isopropylene group, sec-butylene group, tert-butylene group Etc.

Examples of the group in which the methylene group contained in — [CH ₂ ] _k — is substituted with an oxygen atom and / or a carbonyl group include those described above.

  Examples of the aliphatic hydrocarbon group and the alicyclic hydrocarbon group include the same ones as described above. In the alicyclic hydrocarbon group, the methylene group contained therein may be substituted with an oxygen atom or a carbonyl group.

  As a substituent in the alicyclic hydrocarbon group which may have a substituent, a halogen atom, a linear or branched hydrocarbon group having 1 to 6 carbon atoms, a linear or branched carbon number of 1 Represents an aliphatic hydrocarbon group having 12 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, a glycidoxy group, or an acyl group having 2 to 4 carbon atoms.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the hydrocarbon group include the above-described aliphatic hydrocarbon groups and alicyclic hydrocarbons.
Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthranyl group, a p-methylphenyl group, a p-tert-butylphenyl group, and a p-adamantylphenyl group.
Examples of the aralkyl group include benzyl, phenethyl, phenylpropyl, trityl, naphthylmethyl group, naphthylethyl group, and the like.
Examples of the acyl group include acetyl, propionyl, butyryl and the like.

［式（Ｙ１）中、環Ｗは、炭素数３〜３６の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。
Ｒ^ａは、水素原子あるいは直鎖状若しくは分岐状の炭素数１〜６の炭化水素基を表す。
Ｒ^ｂは、互いに独立に、ハロゲン原子、直鎖状若しくは分岐状の炭素数１〜１２の脂肪族炭化水素基、炭素数６〜２０の芳香族炭化水素基、炭素数７〜２１のアラルキル基、グリシドキシ基あるいは炭素数２〜４のアシル基を表す。
ｘは、０〜８の整数を表す。ｘが２以上の場合、複数のＲ^ｂは、同一でも異なってもよい。］ Y ¹ is preferably a group represented by the formula (Y1).

[In Formula (Y1), Ring W represents an alicyclic hydrocarbon group having 3 to 36 carbon atoms, and the methylene group contained in the alicyclic hydrocarbon group is substituted with an oxygen atom or a carbonyl group. Also good.
R ^a represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms.
R ^b is independently of each other a halogen atom, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 21 carbon atoms. Represents a glycidoxy group or an acyl group having 2 to 4 carbon atoms.
x represents an integer of 0 to 8. When x is 2 or more, the plurality of R ^b may be the same or different. ]

Examples of the ring W include groups represented by formulas (W1) to (W25).

Among these, the formula (W12), the formula (W15), the formula (W16), the formula (W20), and the like are preferable.
In other words, Y ¹ preferably has an adamantyl group, an oxo-adamantyl group, or a cyclohexyl group. Moreover, what has a cyclohexyl group of a formula (W4) is preferable.

Y ¹ is a group in which a hydrogen atom contained in the ring W is not substituted or substituted only with a hydrocarbon group (provided that the methylene group contained in the ring W is substituted with an oxygen atom) And a group substituted with a hydroxyl group or a group containing a hydroxyl group (excluding those having a lactone structure) and two adjacent methylene groups contained in the ring W are substituted with an oxygen atom and a carbonyl group. Examples include a group having a lactone structure, a group having a ketone structure in which one methylene group contained in ring W is substituted with a carbonyl group, and a group in which a hydrogen atom contained in ring W is substituted with an aromatic hydrocarbon group. .

環Ｗに含まれる水素原子が芳香族炭化水素基で置換されたＹ^１としては、例えば、以下の基が挙げられる。 The hydrogen atom contained in the ring W is not substituted or substituted only with an aliphatic hydrocarbon group (the methylene group contained in the hydrocarbon group may be substituted with an oxygen atom) as Y ¹ For example, the following groups may be mentioned. The bond can be at any position other than the positions shown below (the same applies hereinafter).

Examples of Y ¹ in which a hydrogen atom contained in the ring W is substituted with an aromatic hydrocarbon group include the following groups.

Examples of Y ¹ in which a hydrogen atom contained in ring W is substituted with a hydroxyl group or a group containing a hydroxyl group (however, having no lactone structure) include the following groups.

Examples of Y ¹ having an ether structure in which one methylene group contained in the ring W is substituted with an oxygen atom include the following groups.

Examples of Y ¹ having a lactone structure in which two adjacent methylene groups contained in ring W are substituted with a carbonyl group and an oxygen atom include the following groups.

Examples of Y ¹ having a ketone structure in which one methylene group contained in ring W is substituted with a carbonyl group include the following groups.

［式（ＩＡ）〜（ＩＤ）中、Ｑ^１、Ｑ^２及びＹ^１は、式（Ｉ）におけるものと同じものを表す。
Ｘ^１０は、単結合あるいは直鎖状若しくは分岐状の炭素数１〜１５のアルキレン基を表す。
Ｘ^１１及びＸ^１２は、互いに独立に、直鎖状若しくは分岐状の炭素数１〜１５のアルキレン基を表す。］
アルキレン基としては、メチレン、エチレン、ｎ−プロピレン基、イソプロピレン基、ｎ−ブチレン基、ｓｅｃ−ブチレン基、ｔｅｒｔ−ブチレン基、ｎ−ペンチレン基、ｎ−ヘキシレン基などのアルカンジエン基が挙げられる。
中でも、Ｘ^１０としては、好ましくは単結合である。 Examples of the anion moiety of the acid generator (A) represented by the formula (I) include anions represented by the following formulas (IA) to (ID).

[In formulas (IA) to (ID), Q ¹ , Q ² and Y ¹ represent the same as those in formula (I).
X ¹⁰ represents a single bond or a linear or branched alkylene group having 1 to 15 carbon atoms.
X ¹¹ and X ¹² each independently represent a linear or branched alkylene group having 1 to 15 carbon atoms. ]
Examples of the alkylene group include alkanediene groups such as methylene, ethylene, n-propylene group, isopropylene group, n-butylene group, sec-butylene group, tert-butylene group, n-pentylene group, and n-hexylene group. .
Among these, X ¹⁰ is preferably a single bond.

  In formula (IA), the hydrogen atom contained in ring W is substituted only with a hydrocarbon group (the methylene group contained in the hydrocarbon group may be substituted with an oxygen atom). For example, the following may be mentioned.

  In the formula (IA), specific examples of the anion in which the hydrogen atom contained in the ring W is substituted with an aromatic hydrocarbon group include the following.

  In the formula (IA), specific examples of the anion in which the hydrogen atom contained in the ring W is substituted with a hydroxyl group or a group containing a hydroxyl group (but not having a lactone structure) include the following. It is done.

  In the formula (IA), specific examples of the anion having an ether structure in which the methylene group contained in the ring W is substituted with an oxygen atom include the followings.

  In the formula (IA), specific examples of the anion having a lactone structure in which two adjacent methylene groups contained in the ring W are substituted with an oxygen atom and a carbonyl group include the following.

  In the formula (IA), specific examples of the anion having a ketone structure in which the methylene group contained in the ring W is substituted with a carbonyl group include the following.

  In formula (IB), the hydrogen atom contained in ring W is not substituted or substituted only with a hydrocarbon group (the methylene group contained in ring W may be substituted with an oxygen atom). Specific examples include the following.

  In the formula (IB), specific examples of the anion in which the hydrogen atom contained in the ring W is substituted with a hydroxyl group or a group containing a hydroxyl group include the following.

  In the formula (IB), specific examples of the anion having a lactone structure in which two adjacent methylene groups contained in the ring W are substituted with an oxygen atom and a carbonyl group include the following.

  In the formula (IB), specific examples of the anion having a ketone structure in which one methylene group contained in the ring W is substituted with a carbonyl group include the following.

  Specific examples of the anion in which the hydrogen atom contained in the ring W in the formula (IB) is substituted with an aromatic hydrocarbon group include the following.

  In formula (IC), a hydrogen atom contained in ring W is not substituted or substituted only with a hydrocarbon group (a methylene group contained in ring W may be substituted with an oxygen atom). Specific examples include the following.

  In the formula (IC), specific examples of the anion in which the hydrogen atom contained in the ring W is substituted with a hydroxyl group or a group containing a hydroxyl group include the following.

  Specific examples of the anion having a ketone structure in which one methylene group contained in the ring W is substituted with a carbonyl group in the formula (IC) include the following.

  In formula (ID), the hydrogen atom contained in ring W is not substituted or substituted only with a hydrocarbon group (the methylene group contained in ring W may be substituted with an oxygen atom). Specific examples include the following.

  In the formula (ID), specific examples of the anion in which the hydrogen atom contained in the ring W is substituted with a hydroxyl group or a group containing a hydroxyl group include the following.

  In the formula (ID), specific examples of the anion having a ketone structure in which one methylene group contained in the ring W is substituted with a carbonyl group include the following.

Among these anions, the following anions are preferable.

Examples of Z ⁺ in formula (I) include cations such as formula (IXa), formula (IXb), formula (IXc), and formula (IXd).

[In formula (IXa), P ^a , P ^b and P ^c are each independently a linear or branched alkyl group having 1 to 30 carbon atoms or an alicyclic hydrocarbon group having 3 to 30 carbon atoms. Represent. When any of P ^a , P ^b, and P ^c is an alkyl group, the alkyl group is a hydroxyl group, a linear or branched alkoxy group having 1 to 12 carbon atoms, or an alicyclic group having 3 to 12 carbon atoms. It may be substituted with a hydrocarbon group, and when any of P ^a , P ^b and P ^c is an alicyclic hydrocarbon group, it is a hydroxyl group, a linear or branched ^C 1-12. It may be substituted with an alkyl group or an alkoxy group having 1 to 12 carbon atoms.
In formula (IXb), P ⁴ and P ⁵ each independently represent a hydrogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
In formula (IXc), P ⁶ and P ⁷ each independently represent a linear or branched alkyl group having 1 to 12 carbon atoms or a cycloalkyl group having 3 to 12 carbon atoms, or P ⁶ and P ^7. And may form a ring having 3 to 12 carbon atoms.
P ⁸ represents a hydrogen atom, and P ⁹ is a linear or branched alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, or an optionally substituted carbon atom having 6 to 20 carbon atoms. Or P ⁸ and P ⁹ may be linked to form a ring having 3 to 12 carbon atoms.
In formula (IXd), P ^{10 to} P ²¹ each independently represent a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
E represents a sulfur atom or an oxygen atom.
m represents 0 or 1. ]

As an alkoxy group, a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentoxy group, an n-hexoxy group, a heptoxy group, an octoxy group Alkyl groups such as 2-ethylhexyloxy group, nonyloxy group, decyloxy group, undecyloxy group, dodecyloxy group, and the like.
Examples of the cycloalkyl group are the same as those described above for the alicyclic hydrocarbon group.
Examples of the ring formed by combining P ⁶ and P ⁷ include a tetrahydrothiophenium group.
The substituent of the aromatic hydrocarbon group for P ^8, include alkyl groups of 1 to 12 carbon atoms.
Examples of the ring formed by combining P ⁸ and P ⁹ include the groups of the above formulas (W13) to (W15).

Among the cations represented by the formula (IXa), for example, a cation represented by the formula (IXaa) and the like are preferable.

[In Formula (IXaa), P ^{1 to} P ³ are each independently a hydrogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 12 carbon atoms, a linear or branched carbon number 1 to 12 represents an alkoxy group having 12 carbon atoms or an alicyclic hydrocarbon having 4 to 36 carbon atoms, and the hydrogen atom contained in the alicyclic hydrocarbon group is a halogen atom, a hydroxyl group, a linear or branched carbon atom having 1 to 12 carbon atoms. A linear or branched alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidoxy group, or an acyl group having 2 to 4 carbon atoms. May be substituted. ]

Here, as the aryl group, phenyl group, naphthyl group, anthranyl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, biphenyl Group, anthryl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl and the like.
Among them, examples of the alicyclic hydrocarbon group include those containing an adamantyl skeleton and an isobornyl skeleton, preferably a 2-alkyl-2-adamantyl group, a 1- (1-adamantyl) -1-alkyl group and an isobornyl group. Etc. are preferable.

Specific examples of the cation represented by the formula (IXaa) include the following.

  Among the cations represented by the formula (IXaa), the cation represented by the formula (IXaaa) is preferably used because of its easy production.

[In formula (IXe), P ²² , P ²³ and P ²⁴ are each independently a hydrogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched carbon atom. The number 1-12 alkoxy group is represented. ]

  Specific examples of the cation represented by the formula (IXb) include the followings.

  Specific examples of the cation represented by the formula (IXc) include the followings.

  Specific examples of the cation represented by the formula (IXd) include the followings.

上記カチオンのうち、アリールスルホニウムカチオンが好ましい。

Of the above cations, arylsulfonium cations are preferred.

The above anions and cations can be arbitrarily combined.
For example, examples of the compound represented by the formula (I) include compounds represented by the formula (Xa) to the formula (Xi). These compounds are preferable because they generate an acid that gives a resist composition exhibiting excellent resolution performance and pattern shape.

［式（Ｘａ）〜（Ｘｉ）中、Ｐ^２５、Ｐ^２６及びＰ^２７は、互いに独立に、水素原子、直鎖状若しくは分岐状の炭素数１〜４の脂肪族炭化水素基あるいは炭素数４〜３６の脂環式炭化水素基を表す。
Ｐ^２８及びＰ^２９は、互いに独立に、直鎖状若しくは分岐状の炭素数１〜１２の脂肪族炭化水素基あるいは炭素数４〜３６の脂環式炭化水素基を表すか、あるいはＰ^２８とＰ^２９とが連結してＳ^＋を含む炭素数２〜６の環を形成してもよい。
Ｐ^３０は、水素原子を表し、Ｐ^３１は、直鎖状若しくは分岐状の炭素数１〜１２の脂肪族炭化水素基、炭素数４〜３６の脂環式炭化水素基あるいは置換されていてもよい炭素数６〜２０の芳香族炭化水素基を表すか、あるいはＰ^３０とＰ^３１とが連結して炭素数３〜１２の環を形成してもよい。
ここで、該環に含まれるメチレン基は、任意に、酸素原子又はカルボニル基で置換されていてもよい。
Ｑ^１及びＱ^２は、上記と同義である。
Ｘ^１３は、単結合またはメチレン基を表す。］

[In Formulas (Xa) to (Xi), P ²⁵ , P ²⁶ and P ²⁷ are each independently a hydrogen atom, a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms, or 4 carbon atoms. -36 alicyclic hydrocarbon groups are represented.
P ²⁸ and P ²⁹ each independently represent a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 4 to 36 carbon atoms, or P ²⁸ and P ²⁹ may be linked to form a C 2-6 ring containing S ⁺ .
P ³⁰ represents a hydrogen atom, and P ³¹ may be a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 36 carbon atoms, or a substituted group. It represents a good aromatic hydrocarbon group having 6 to 20 carbon atoms, or P ³⁰ and P ³¹ may be linked to form a ring having 3 to 12 carbon atoms.
Here, the methylene group contained in the ring may be optionally substituted with an oxygen atom or a carbonyl group.
Q ¹ and Q ² are as defined above.
X ¹³ represents a single bond or a methylene group. ]

Examples of the ring and P ²⁸ and P ²⁹ are formed together, such as tetrahydrothiophenium group.
Examples of the ring formed by combining P ³⁰ and P ³¹ include the groups of the above-described formulas (W13) to (W15).

Of the above combinations, the following acid generators are preferred.

Among them, in the cation represented by the formula (IXe) as a cation, specific examples of the triphenylsulfonium cation in which P ²² , P ²³ and P ²⁴ are all hydrogen atoms and the anion represented by the formula (IB) Acid generators in combination with those listed are preferred.
The acid generators represented by formula (I) may be used alone or in combination of two or more.

  The acid generator (A) represented by the formula (I) is, for example, a salt represented by the formula (1) and an onium salt represented by the formula (3) such as acetonitrile, water, methanol, etc. In an inert solvent, the mixture is reacted by stirring in a temperature range of about 0 to 150 ° C., preferably about 0 to 100 ° C., to obtain the acid generator (A) as a salt. be able to.

［式中、Ｑ^１、Ｑ^２、Ｘ^１、Ｙ^１及びＺ^＋は、式（Ｉ）におけるものと同義であり、
Ｍ^＋は、Ｌｉ^＋、Ｎａ^＋、Ｋ^＋又はＡｇ^＋を表す。
Ｚ^１−は、Ｆ⁻、Ｃｌ⁻、Ｂｒ⁻、Ｉ⁻、ＢＦ_４ ⁻、ＡｓＦ_６ ⁻、ＳｂＦ_６ ⁻、ＰＦ_６ ⁻又はＣｌＯ_４ ⁻を表す。］

[Wherein Q ¹ , Q ² , X ¹ , Y ¹ and Z ⁺ are the same as those in formula (I);
M ⁺ represents Li ⁺ , Na ⁺ , K ⁺ or Ag ⁺ .
Z ¹⁻ represents F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , BF ₄ ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , PF ₆ ⁻ or ClO ₄ ⁻ . ]

  The usage-amount of the onium salt of Formula (3) is about 0.5-2 mol normally with respect to 1 mol of salts represented by Formula (1). The salt may be taken out by recrystallization or may be purified by washing with water.

  The salt represented by the formula (1) can be obtained, for example, by first esterifying the alcohol represented by the formula (4) and the carboxylic acid represented by the formula (6).

［式中、Ｑ^１、Ｑ^２、Ｘ^１、Ｙ^１及びＭ^＋は上記と同義である。］

[Wherein, Q ¹ , Q ² , X ¹ , Y ¹ and M ⁺ are as defined above. ]

  The amount of the carboxylic acid represented by the formula (6) in the esterification reaction is usually about 0.2 to 3 mol, preferably 0.5 to 1 mol with respect to 1 mol of the alcohol represented by the formula (4). About 2 moles. The amount of the acid catalyst used in the esterification reaction may be a catalytic amount or an amount corresponding to a solvent, and is usually about 0.001 to 5 mol.

［式中、Ｑ^１、Ｑ^２、Ｘ^１及びＹ^１は上記と同義である。ＭＯＨにおけるＭは、Ｍ^＋のＭと同じ元素を表す。］ In addition, the salt represented by the formula (1) can be obtained by, for example, esterifying the alcohol represented by the formula (4) and the carboxylic acid represented by the formula (7) and then hydrolyzing with MOH. Can also be manufactured.

[Wherein, Q ¹ , Q ² , X ¹ and Y ¹ are as defined above] M in MOH represents the same element as M in M ⁺ . ]

The esterification reaction is usually stirred in an aprotic solvent such as dichloroethane, toluene, ethylbenzene, monochlorobenzene, acetonitrile, etc. in a temperature range of about 20 to 200 ° C., preferably in a temperature range of about 50 to 150 ° C. You can do it. In the esterification reaction, an organic acid such as p-toluenesulfonic acid and / or an inorganic acid such as sulfuric acid may be added as an acid catalyst.
Further, the esterification reaction may be carried out while dehydrating, such as by using a Dean Stark apparatus.
The

  Further, among the salts represented by the formula (1), the salt having an anion represented by the formula (IA) is, for example, firstly a carboxylic acid represented by the formula (8) and a formula (9). It can be obtained by esterifying the alcohol represented.

［式（８）および式（９）中、Ｑ^１、Ｑ^２、Ｘ^１、Ｙ^１及びＭ^＋は上記と同義である。］ 前記の反応は、式（ＩＢ）で表されるアニオンを有する塩の製造においても、同様に適用できる。

[In formula (8) and formula (9), Q ¹ , Q ² , X ¹ , Y ¹ and M ⁺ are as defined above. The above reaction can be similarly applied to the production of a salt having an anion represented by the formula (IB).

［式（ＩＩ’）中、Ｑ^１、Ｑ^２、Ｙ^１及びＺ^＋は、式（Ｉ）におけるものと同じ意味を表す。
Ｘ^１１は、直鎖状若しくは分岐状の炭素数１〜１５のアルキレン基を表す。］ Examples of the method for producing an acid generator having an anion represented by (IC) include a method for producing a salt represented by the following formula (II ′).

[In formula (II ′), Q ¹ , Q ² , Y ¹ and Z ⁺ represent the same meaning as in formula (I).
X ¹¹ represents a linear or branched alkylene group having 1 to 15 carbon atoms. ]

  Examples of the method for producing the salt represented by the formula (II ′) include a salt represented by the formula (IIa ′) and an onium salt represented by the formula (IIb ′), for example, acetonitrile, water, methanol. , In an inert solvent such as chloroform, methylene chloride, or a mixed solvent thereof, in a temperature range of about 0 to 150 ° C., preferably in a temperature range of about 0 to 100 ° C. Etc.

［式（ＩＩａ’）中、Ｑ^１、Ｑ^２、Ｘ^１１及びＹ^１は、式（ＩＩ’）におけるものと同じ意味を表す。
Ｍ^＋は、Ｌｉ^＋、Ｎａ^＋又はＫ^＋を表す。
式（ＩＩｂ’）中、Ｚ^＋は、式（ＩＩ’）におけるものと同じ意味を表す。
Ｘ⁻は、Ｂｒ⁻又はＩ⁻を表す。］
ここで、Ｑ^１及びＱ^２としては、互いに独立に、フッ素原子又はトリフルオロメチル基である場合が好ましく、フッ素原子である場合がさらに好ましい。

[In formula (IIa ′), Q ¹ , Q ² , X ¹¹ and Y ¹ represent the same meaning as in formula (II ′).
M ⁺ represents Li ⁺ , Na ⁺ or K ⁺ .
In formula (IIb ′), Z ⁺ represents the same meaning as in formula (II ′).
X ⁻ represents Br ⁻ or I ⁻ . ]
Here, Q ¹ and Q ² are each independently preferably a fluorine atom or a trifluoromethyl group, and more preferably a fluorine atom.

The amount of the onium salt represented by the formula (IIb ′) is usually about 0.5 to 2 mol relative to 1 mol of the salt represented by the formula (IIa ′).
The salt represented by the formula (II ′) may be taken out by recrystallization or may be purified by washing with water.

［式（ＩＩａ’−１）中、Ｍ^＋、Ｘ^１１、Ｑ^１及びＱ^２は、式（ＩＩａ’）におけるものと同じ意味を表す。
式（ＩＩａ’−２）中、Ｙ^１は、式（ＩＩａ）におけるものと同じ意味を表す。］ As a method for producing the salt represented by the formula (IIa ′), for example, first, the salt represented by the formula (IIa′-1) and the carboxylic acid represented by the formula (IIa′-2) are esterified. The method of making it react is mentioned.

[In formula (IIa′-1), M ⁺ , X ¹¹ , Q ¹ and Q ² represent the same meaning as in formula (IIa ′).
In formula (IIa′-2), Y ¹ represents the same meaning as in formula (IIa). ]

As another method for producing the salt represented by the formula (IIa ′), an esterification reaction between an alcohol represented by the formula (IIa′-3) and a carboxylic acid represented by the formula (IIa′-2) There is also a method for producing a salt represented by the formula (IIa ′) by hydrolyzing with an alkali metal hydroxide represented by MOH. Here, the alkali metal of the alkali metal hydroxide is the same as the alkali metal of the alkali metal cation represented by M ⁺ in the formula (IIa′-1).

［式（ＩＩａ’−３）中、Ｘ^１１、Ｑ^１及びＱ^２は、式（ＩＩａ’）におけるものと同じ意味を表す。
式（ＩＩａ’−２）中、Ｙ^１は、式（ＩＩａ）におけるものと同じ意味を表す。］

[In formula (IIa′-3), X ¹¹ , Q ¹ and Q ² represent the same meaning as in formula (IIa ′).
In formula (IIa′-2), Y ¹ represents the same meaning as in formula (IIa). ]

Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide and potassium hydroxide, preferably lithium hydroxide and sodium hydroxide.
Here, Q ¹ and Q ² are each independently preferably a fluorine atom or a trifluoromethyl group, and more preferably a fluorine atom.

The esterification reaction between the carboxylic acid represented by the formula (IIa′-2) and the salt represented by the formula (IIa′-1) is usually performed by dichloroethane, toluene, ethylbenzene, monochlorobenzene, acetonitrile, N, N— What is necessary is just to stir in a temperature range of about 20-200 degreeC normally in an aprotic solvent, such as dimethylformamide, Preferably it is about 50-150 degreeC.
In the esterification reaction, an acid catalyst is usually added. Examples of the acid catalyst include organic acids such as p-toluenesulfonic acid and inorganic acids such as sulfuric acid.

Furthermore, a dehydrating agent may be added in the esterification reaction. Examples of the dehydrating agent include dicyclohexylcarbodiimide, 1-alkyl-2-halopyridinium salt, 1,1-carbonyldiimidazole, bis (2-oxo-3-oxazolidinyl) phosphine chloride, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, di-2-pyridyl carbonate, di-2-pyridylthiono carbonate, 6-methyl-2-nitrobenzoic anhydride in the presence of 4- (dimethylamino) pyridine, etc. Is mentioned.
The esterification reaction using an acid catalyst is preferably carried out while dehydrating using a Dean Stark apparatus or the like because the reaction time tends to be shortened.

As the usage-amount of the salt represented by Formula (IIa'-1) in esterification reaction, it is about 0.5-3 mol normally with respect to 1 mol of carboxylic acids represented by Formula (IIa'-2). The amount is preferably about 1 to 2 moles.
The acid catalyst in the esterification reaction may be a catalytic amount or an amount corresponding to a solvent with respect to 1 mol of the carboxylic acid represented by the formula (IIa′-2), and is usually about 0.001 to 5 mol.
The dehydrating agent in the esterification reaction is usually about 0.5 to 5 mol, preferably about 1 to 3 mol, relative to 1 mol of the carboxylic acid represented by the formula (IIa′-2).

The esterification reaction between the carboxylic acid represented by the formula (IIa′-2) and the salt represented by the formula (IIa′-1) is carried out by reacting the carboxylic acid represented by the formula (IIa′-2) with the corresponding acid. It can also carry out by converting into a halide and making it react with the salt represented by a formula (IIa'-1), and the compound represented by a formula (IIa ') can also be obtained by the reaction.
Examples of the reagent that converts to an acid halide include thionyl chloride, thionyl bromide, phosphorus trichloride, phosphorus pentachloride, and phosphorus tribromide.
Examples of the solvent used in the acid halide reaction include aprotic solvents such as dichloroethane, toluene, ethylbenzene, monochlorobenzene, and N, N-dimethylformamide.
The reaction may be usually carried out with stirring in a temperature range of about 20 to 200 ° C., preferably in a temperature range of about 50 to 150 ° C.

In the above reaction, an amine compound can be added as a catalyst.
Examples of the obtained acid halide include salts represented by the formula (IIa′-1) and inert solvents (for example, aprotic solvents such as dichloroethane, toluene, ethylbenzene, monochlorobenzene, N, N-dimethylformamide, and the like). To obtain a salt represented by the formula (IIa ′).
The reaction is usually carried out in a temperature range of about 20 to 200 ° C., preferably in a temperature range of about 50 to 150 ° C., and preferably a deoxidizer is used.
Examples of the deoxidizer include organic bases such as triethylamine and pyridine, and inorganic bases such as sodium hydroxide, potassium carbonate, and sodium hydride.
The amount of the base used may be an amount corresponding to the solvent with respect to 1 mol of the acid halide, and is usually about 0.001 to 5 mol, preferably about 1 to 3 mol.

［式（ＩＩ”）中、Ｑ^１、Ｑ^２Ｙ^１及びＺ^＋は、式（Ｉ）におけるものと同じ意味を表す。
Ｘ^１１は、互いに独立に、直鎖状若しくは分岐状の炭素数１〜１５のアルキレン基を表す。］ Examples of the method for producing an acid generator having an anion represented by the formula (ID) include a method for producing a salt represented by the following formula (II ″).

[In Formula (II ″), Q ¹ , Q ² Y ¹ and Z ⁺ represent the same meaning as in Formula (I).
X ¹¹ represents, independently of each other, a linear or branched alkylene group having 1 to 15 carbon atoms. ]

  Examples of the method for producing the salt represented by the formula (II ″) include a salt represented by the formula (IIa ″) and an onium salt represented by the formula (IIb ″), for example, acetonitrile, water, methanol. In an inert solvent such as chloroform, methylene chloride, or a mixed solvent thereof, usually with stirring in a temperature range of about 0 to 150 ° C., preferably in a temperature range of about 0 to 100 ° C. The method of making it, etc. are mentioned.

［式（ＩＩａ”）中、Ｑ^１、Ｑ^２、Ｘ^１１及びＹ^１は、式（ＩＩ”）におけるものと同じ意味を表す。
Ｍ^＋は、Ｌｉ^＋、Ｎａ^＋又はＫ^＋を表す。
式（ＩＩｂ”）中、Ｚ^＋は、式（ＩＩ”）におけるものと同じ意味を表す。
Ｘ⁻は、Ｂｒ⁻又はＩ⁻を表す。］

[In formula (IIa ″), Q ¹ , Q ² , X ¹¹ and Y ¹ represent the same meaning as in formula (II ″).
M ⁺ represents Li ⁺ , Na ⁺ or K ⁺ .
In formula (IIb ″), Z ⁺ represents the same meaning as in formula (II ″).
X ⁻ represents Br ⁻ or I ⁻ . ]

The amount of the onium salt represented by the formula (IIb ″) is usually about 0.5 to 2 mol relative to 1 mol of the salt represented by the formula (IIa ″).
The obtained salt represented by the formula (II ″) may be taken out by recrystallization or may be purified by washing with water.
Here, Q ¹ and Q ² are each independently preferably a fluorine atom or a trifluoromethyl group, and more preferably a fluorine atom.

  As a method for producing the salt represented by the formula (IIa ″), for example, first, the salt represented by the formula (IIa ″ -1) and the alcohol represented by the formula (IIa ″ -2) are esterified. The method of letting it be mentioned.

［式（ＩＩａ”−１）中、Ｍ^＋、Ｘ^１１、Ｑ^１及びＱ^２は、式（ＩＩａ”）におけるものと同じ意味を表す。
式（ＩＩａ”−２）中、Ｙ^１は、式（ＩＩａ”）におけるものと同じ意味を表す。］

[In formula (IIa ″ -1), M ⁺ , X ¹¹ , Q ¹ and Q ² represent the same meaning as in formula (IIa ″).
In formula (IIa ″ -2), Y ¹ represents the same meaning as in formula (IIa ″). ]

  As another method for producing the salt represented by the formula (IIa ″), after reacting the alcohol represented by the formula (IIa ″ -3) with the alcohol represented by the formula (IIa ″ -2) There is also a method of obtaining a salt represented by the formula (IIa ″) by dehydration condensation with an alkali metal hydroxide represented by MOH.

［式（ＩＩａ”−３）中、Ｘ^１１、Ｑ^１及びＱ^２は、式（ＩＩａ”）におけるものと同じ意味を表す。
式（ＩＩａ”−２）中、Ｙ^１は、式（ＩＩａ”）におけるものと同じ意味を表す。
ＭＯＨにおけるＭは、上記と同じ意味を表す。］
ここで、Ｑ^１及びＱ^２としては、互いに独立に、フッ素原子又はトリフルオロメチル基である場合が好ましく、フッ素原子である場合がさらに好ましい。

[In formula (IIa ″ -3), X ¹¹ , Q ¹ and Q ² represent the same meaning as in formula (IIa ″).
In formula (IIa ″ -2), Y ¹ represents the same meaning as in formula (IIa ″).
M in MOH represents the same meaning as described above. ]
Here, Q ¹ and Q ² are each independently preferably a fluorine atom or a trifluoromethyl group, and more preferably a fluorine atom.

The etherification reaction between the alcohol represented by the formula (IIa ″ -2) and the alcohol represented by the formula (IIa ″ -1) is usually performed by dichloroethane, toluene, ethylbenzene, monochlorobenzene, acetonitrile, N, N-dimethyl. What is necessary is just to stir in a temperature range of about 20-200 degreeC normally in an aprotic solvent, such as formamide, Preferably it is about 50-150 degreeC.
In the etherification reaction, an organic acid such as p-toluenesulfonic acid or an inorganic acid such as sulfuric acid is usually added as an acid catalyst.
Further, in the etherification reaction, a dehydrating agent may be added, and 1,1′-carbonyldiimidazole, N, N′-dicyclohexylcarbodiimide or the like may be added as the dehydrating agent.
The etherification reaction using an acid catalyst is preferably carried out while dehydrating using a Dean Stark apparatus or the like because the reaction time tends to be shortened.

The amount of the alcohol represented by the formula (IIa ″ -1) in the etherification reaction is usually about 0.5 to 3 mol with respect to 1 mol of the alcohol represented by the formula (IIa ″ -2). The amount is preferably about 1 to 2 moles.
The acid catalyst in the etherification reaction may be a catalytic amount or an amount corresponding to a solvent with respect to 1 mol of the alcohol represented by the formula (IIa ″ -2), and is usually about 0.001 to 5 mol.
The dehydrating agent in the etherification reaction is usually about 0.5 to 5 mol, preferably about 1 to 3 mol per 1 mol of the alcohol represented by the formula (IIa ″ -2).

  The etherification reaction between the compound represented by the formula (IIa ″ -2) and the alcohol represented by the formula (IIa ″ -1) is carried out by converting the alcohol represented by the formula (IIa ″ -2) into the formula (IIa ″ − 4) conversion to the compound represented by 4) and reacting the obtained compound represented by the formula (IIa ″ -4) with the alcohol represented by the formula (IIa ″ -1). Thereby, the compound represented by the formula (IIa ″) can also be obtained.

［式（ＩＩａ”−１）中、Ｍ^＋、Ｘ^１１、Ｑ^１及びＱ^２は、式（ＩＩａ”）におけるものと同じ意味を表す。
式（ＩＩａ”−２）及び式（ＩＩａ”−４）中、Ｙ^１は、式（ＩＩ”）におけるものと同じ意味を表す。
Ｌは、塩素、臭素、ヨウ素、メシルオキシ基、トシルオキシ基又はトリフルオロメタンスルホニルオキシ基を表す。］

[In formula (IIa ″ -1), M ⁺ , X ¹¹ , Q ¹ and Q ² represent the same meaning as in formula (IIa ″).
In formula (IIa ″ -2) and formula (IIa ″ -4), Y ¹ represents the same meaning as in formula (II ″).
L represents chlorine, bromine, iodine, mesyloxy group, tosyloxy group or trifluoromethanesulfonyloxy group. ]

  In order to convert the alcohol represented by the formula (IIa ″ -2) into the compound represented by the formula (IIa ″ -4), for example, thionyl chloride, thionyl bromide, phosphorus trichloride, phosphorus pentachloride, tribromide. Phosphorus, mesyl chloride, tosyl chloride, trifluoromethanesulfonic anhydride, etc. are reacted with an alcohol represented by the formula (IIa ″ -2). The above reaction is carried out using an inert solvent such as dichloroethane, toluene, ethylbenzene, mono It is suitable to carry out in an aprotic solvent such as chlorobenzene, N, N-dimethylformamide, etc. The reaction is usually in the temperature range of about -70 to 200 ° C., preferably about -50 to 150 ° C. It is preferable to use a deoxidizer by stirring in the temperature range.

Examples of the deoxidizer include organic bases such as triethylamine and pyridine, and inorganic bases such as sodium hydroxide, potassium carbonate, and sodium hydride.
The amount of the base used may be an amount corresponding to the solvent with respect to 1 mol of the alcohol represented by the formula (IIa ″ -2), and is usually about 0.001 to 5 mol, preferably about 1 to 3 mol. It is.

The obtained compound represented by the formula (IIa ″ -4) includes a salt represented by the formula (IIa ″ -1) and an inert solvent such as dichloroethane, toluene, ethylbenzene, monochlorobenzene, N, N-dimethyl. By reacting in an aprotic solvent such as formamide, a salt represented by the formula (IIa ″) can be obtained.
The reaction is usually performed in a temperature range of about 20 to 200 ° C, preferably in a temperature range of about 50 to 150 ° C.
In the above reaction, a deoxidizer is preferably used.
Examples of the deoxidizer include organic bases such as triethylamine and pyridine, and inorganic bases such as sodium hydroxide, potassium carbonate, and sodium hydride.
When using a deoxidizing agent, the amount thereof may be an amount corresponding to a solvent with respect to 1 mol of the compound represented by the formula (IIa ″ -4), and is usually about 0.001 to 5 mol, preferably About 1 to 3 moles.

  In the resist composition of the present invention, the content of the acid generator (A) is preferably 1 to 20 parts by mass, and 1 to 15 parts by mass with respect to 100 parts by mass of the resin (B). It is more preferable.

The resist composition of the present invention can contain a basic compound, preferably a basic nitrogen-containing organic compound, particularly preferably an amine or ammonium salt, together with the acid generator (A) and the resin (B). By adding a basic compound, for example, as a quencher, it is possible to improve performance deterioration due to acid deactivation accompanying holding after exposure.
As a basic compound used for a quencher, the following are mentioned, for example.

式中、Ｔ^１、Ｔ^２及びＴ^７は、互いに独立に、水素原子、炭素数１〜６の脂肪族炭化水素基、炭素数５〜１０の脂環式炭化水素基又は炭素数６〜２０の芳香族炭化水素基を表す。該脂肪族炭化水素基の水素原子、該脂環式炭化水素基の水素原子及び芳香族炭化水素基の水素原子は、水酸基、アミノ基又は炭素数１〜６のアルコキシ基で置換されていてもよい。該アミノ基の水素原子は、炭素数１〜４の脂肪族炭化水素基で置換されていてもよい。

In the formula, T ¹ , T ² and T ⁷ are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 5 to 10 carbon atoms, or 6 to 20 carbon atoms. Represents an aromatic hydrocarbon group. The hydrogen atom of the aliphatic hydrocarbon group, the hydrogen atom of the alicyclic hydrocarbon group, and the hydrogen atom of the aromatic hydrocarbon group may be substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. Good. The hydrogen atom of the amino group may be substituted with an aliphatic hydrocarbon group having 1 to 4 carbon atoms.

T ^{3 to} T ⁵ are each independently a hydrogen atom, a linear or branched aliphatic hydrocarbon group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, carbon An alicyclic hydrocarbon group having 5 to 10 carbon atoms or an aromatic hydrocarbon group having 6 to 20 carbon atoms is represented. The hydrogen atom of the aliphatic hydrocarbon group, the hydrogen atom of the alicyclic hydrocarbon group, the hydrogen atom of the aromatic hydrocarbon group and the hydrogen atom of the alkoxy group are independently of each other a hydroxyl group, an amino group or a straight chain. Or a branched or branched alkoxy group having 1 to 6 carbon atoms. The hydrogen atom of the amino group may be substituted with a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms.

T ⁶ represents a linear or branched aliphatic hydrocarbon group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 10 carbon atoms. The hydrogen atom of the aliphatic hydrocarbon group or the hydrogen atom of the alicyclic hydrocarbon group is independently substituted with a hydroxyl group, an amino group, or a linear or branched alkoxy group having 1 to 6 carbon atoms. May be. The hydrogen atom of the amino group may be substituted with a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms.

  A represents an alkylene group having 1 to 6 carbon atoms, a carbonyl group, an imino group, a sulfide group, or a disulfide group.

  Examples of such compounds include diisopropylaniline, hexylamine, heptylamine, octylamine, nonylamine, decylamine, aniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, 1- or 2-naphthylamine, and ethylenediamine. , Tetramethylenediamine, hexamethylenediamine, 4,4′-diamino-1,2-diphenylethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′- Diethyldiphenylmethane, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, N-methylaniline, piperidine, diphenylamine, triethylamine, trimethylamine, tripropyl Min, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, Methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine, N, N-dimethylaniline, 2,6-isopropylaniline, imi Sol, pyridine, 4-methylpyridine, 4-methylimidazole, bipyridine, 2,2′-dipyridylamine, di-2-pyridyl ketone, 1,2-di (2-pyridyl) ethane, 1,2-di (4 -Pyridyl) ethane, 1,3-di (4-pyridyl) propane, 1,2-bis (2-pyridyl) ethylene, 1,2-bis (4-pyridyl) ethylene, 1,2-bis (4-pyridyl) Oxy) ethane, 4,4′-dipyridyl sulfide, 4,4′-dipyridyl disulfide, 1,2-bis (4-pyridyl) ethylene, 2,2′-dipiconylamine, 3,3′-dipiconylamine, Tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetra-n-hexylammonium hydroxide Examples thereof include xoxide, tetra-n-octylammonium hydroxide, phenyltrimethylammonium hydroxide, 3- (trifluoromethyl) phenyltrimethylammonium hydroxide, and choline.

  Furthermore, a hindered amine compound having a piperidine skeleton described in JP-A No. 11-52575 may be used as a quencher.

  Of these, diisopropylaniline and the quaternary ammonium salts exemplified in the above formula are suitable. Examples thereof include tetramethylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, and 3-trifluoromethyl-phenyltrimethylammonium hydroxide.

  When the resist composition of the present invention contains a basic compound as a quencher, the content of the basic compound is preferably 0.01 to 5 parts by mass, more preferably 0 with respect to 100 parts by mass of the resin. 0.05 to 3 parts by mass.

The resist composition of the present invention is usually provided in a state where each of the above components is dissolved in a solvent.
Examples of the solvent include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate, esters such as ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate, acetone, methyl isobutyl ketone , Ketones such as 2-heptanone and cyclohexanone, cyclic esters such as γ-butyrolactone, and propylene glycol monomethyl ether. You may use these individually or in combination of 2 or more types.

  The resist composition of the present invention may further contain various additives such as a sensitizer, a dissolution inhibitor, other resins, a surfactant, a stabilizer, and a dye as necessary. As these additives, all additives known in the art can be used.

The pattern forming method of the present invention comprises:
(1) The process of apply | coating the resist composition of this invention mentioned above on a board | substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) The process which develops the composition layer after a heating using a image development apparatus is included.

  Application of the resist composition onto the substrate can be performed by a commonly used apparatus such as a spin coater.

The removal of the solvent is performed, for example, by evaporating the solvent using a heating device such as a hot plate or by using a decompression device to form a composition layer from which the solvent has been removed. As for the temperature in this case, about 50-200 degreeC is illustrated, for example. The pressure is, for example, about 1 to 1.0 × 10 ⁵ Pa.

The obtained composition layer is exposed using an exposure machine. Further, an immersion exposure machine may be used. At this time, exposure is usually performed through a mask corresponding to a required pattern. The exposure light source emits ultraviolet laser light such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F ₂ laser (wavelength 157 nm), solid-state laser light source (YAG or semiconductor laser, etc.) Various types of laser beam can be used, such as those that convert the wavelength of the laser beam from) to radiate a harmonic laser beam in the far ultraviolet region or the vacuum ultraviolet region.

The composition layer after the exposure is subjected to heat treatment for promoting the deprotection group reaction. As heating temperature, it is about 50-200 degreeC normally, Preferably it is about 70-150 degreeC.
The heated composition layer is usually developed using an alkali developer using a developing device.
The alkaline developer used here may be various alkaline aqueous solutions used in this field. Examples thereof include an aqueous solution of tetramethylammonium hydroxide and (2-hydroxyethyl) trimethylammonium hydroxide (commonly called choline).
After development, it is preferable to rinse with ultrapure water to remove water remaining on the substrate and the pattern.
The chemically amplified photoresist composition of the present invention is preferably used as a positive type.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.
In Examples and Comparative Examples, “%” and “part” representing the content or amount used are based on mass unless otherwise specified. The weight average molecular weight is a value obtained by gel permeation chromatography using polystyrene as a standard product.

Apparatus: HLC-8120GPC (manufactured by Tosoh Corporation)
Column: 3 TSKgel Multipore HXL-M + guardcolumn (manufactured by Tosoh Corporation)
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min
Detector: RI detector Column temperature: 40 ° C
Injection volume: 100 μL
Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation)

  The structure of the compound was confirmed by NMR (GX-270 type or EX-270 type manufactured by JEOL Ltd.) and mass spectrometry (LC: Agilent 1100 type, MASS: Agilent LC / MSD type or LC / MSD TOF type).

式（Ａ１−ａ）で表される化合物１００部及びイオン交換水１５０部に、氷浴下、３０％水酸化ナトリウム水溶液２３０部を滴下した。得られた混合物を１００℃で３時間還流し、冷却後、これを濃塩酸８８部で中和した。得られた溶液を濃縮することにより式（Ａ１−ｂ）で表される化合物１６４．４部（無機塩含有、純度６２．７％）を得た。得られた式（Ａ１−ｂ）で表される化合物１．９部（純度６２．７％）及びＮ，Ｎ−ジメチルホルムアミド９．５部に、１，１’−カルボニルジイミダゾール１．０部を添加し、２時間撹拌して混合物を調製した。
一方、式（Ａ１−ｃ）で表される化合物１．１部及びＮ，Ｎ−ジメチルホルムアミド５．５部に、水素化ナトリウム０．２部を添加し、２時間撹拌した。この溶液に、前記の混合物を添加した。得られた混合物を１５時間撹拌した後、生成した式（Ａ１−ｄ）で表される化合物を含む溶液をそのまま次の反応に用いた。

得られた式（Ａ１−ｄ）で表される化合物を含む溶液に、クロロホルム１７．２部及び式（Ａ１−ｅ）で表される化合物水溶液（１４．８％）２．９部を添加した。１５時間撹拌した後、分液して有機層を回収した。次いで、残った水層をクロロホルム６．５部で抽出することにより有機層を回収した。さらに残った水層に、前記の抽出操作を繰り返して行い、さらに有機層を回収した。前記の各有機層を合せた後、イオン交換水で洗浄し、その後、得られた有機層を濃縮した。濃縮物にｔｅｒｔ−ブチルメチルエーテル５．０部を添加し、撹拌後、濾過することにより白色固体として式（Ａ１）で表される化合物０．２部を得た。 (Synthesis of acid generator A1)

To 100 parts of the compound represented by the formula (A1-a) and 150 parts of ion-exchanged water, 230 parts of a 30% aqueous sodium hydroxide solution was added dropwise in an ice bath. The resulting mixture was refluxed at 100 ° C. for 3 hours, cooled, and neutralized with 88 parts of concentrated hydrochloric acid. The obtained solution was concentrated to obtain 164.4 parts (containing an inorganic salt, purity 62.7%) of the compound represented by the formula (A1-b). To 1.9 parts (purity 62.7%) of the compound represented by the formula (A1-b) and 9.5 parts of N, N-dimethylformamide, 1.0 part of 1,1′-carbonyldiimidazole is obtained. Was added and stirred for 2 hours to prepare a mixture.
On the other hand, 0.2 part of sodium hydride was added to 1.1 parts of the compound represented by the formula (A1-c) and 5.5 parts of N, N-dimethylformamide, followed by stirring for 2 hours. To this solution was added the above mixture. The obtained mixture was stirred for 15 hours, and then the solution containing the compound represented by the formula (A1-d) was used in the next reaction as it was.

To the obtained solution containing the compound represented by the formula (A1-d), 17.2 parts of chloroform and 2.9 parts of an aqueous compound solution (14.8%) represented by the formula (A1-e) were added. . After stirring for 15 hours, the organic layer was recovered by liquid separation. Subsequently, the remaining aqueous layer was extracted with 6.5 parts of chloroform to recover the organic layer. Further, the above extraction operation was repeated on the remaining aqueous layer, and the organic layer was further recovered. The organic layers were combined, washed with ion-exchanged water, and then the obtained organic layer was concentrated. To the concentrate, 5.0 parts of tert-butyl methyl ether was added, stirred and then filtered to obtain 0.2 parts of a compound represented by the formula (A1) as a white solid.

式（Ａ１−ａ）で表される化合物１００部及びイオン交換水２５０部に、氷浴下、３０％水酸化ナトリウム水溶液２３０部を滴下した。得られた混合物を１００℃で３時間還流し、冷却した後、これを濃塩酸８８部で中和した。得られた溶液を濃縮することにより式（Ａ１−ｂ）で表される化合物１６４．８部（無機塩含有、純度６２．６％）を得た。得られた式（Ａ１−ｂ）で表される化合物５．０部（純度６２．６％）、式（Ａ２−ｃ）で表される化合物２．６部及びエチルベンゼン１００部の混合物に、濃硫酸０．８部を加え、３０時間加熱還流した。得られた混合物を冷却した後、濾過し、濾過残渣をｔｅｒｔ−ブチルメチルエーテルで洗浄することにより、式（Ａ２−ｄ）で表される化合物５．５部を得た。
^１Ｈ−ＮＭＲによる純度分析の結果、その純度は３５．６％であった。 (Synthesis of acid generator A2)

To 100 parts of the compound represented by the formula (A1-a) and 250 parts of ion-exchanged water, 230 parts of a 30% aqueous sodium hydroxide solution was added dropwise in an ice bath. The resulting mixture was refluxed at 100 ° C. for 3 hours, cooled, and neutralized with 88 parts of concentrated hydrochloric acid. The obtained solution was concentrated to obtain 164.8 parts of a compound represented by the formula (A1-b) (containing an inorganic salt, purity 62.6%). To a mixture of 5.0 parts of the compound represented by the formula (A1-b) (purity 62.6%), 2.6 parts of the compound represented by the formula (A2-c) and 100 parts of ethylbenzene, Sulfuric acid 0.8 part was added and it heated and refluxed for 30 hours. The obtained mixture was cooled and then filtered, and the filtration residue was washed with tert-butyl methyl ether to obtain 5.5 parts of a compound represented by the formula (A2-d).
As a result of purity analysis by ¹ H-NMR, the purity was 35.6%.

得られた式（Ａ２−ｄ）で表される化合物５．４部（純度３５．６％）に、アセトニトリル１６部及びイオン交換水１６部を加えた。得られた混合物に、式（Ａ１−ｅ）で表される化合物１．７部、アセトニトリル５部及びイオン交換水５部を添加した。得られた混合物を１５時間撹拌した後、濃縮し、得られた混合物をクロロホルム１４２部で抽出することにより有機層を回収した。回収された有機層をイオン交換水で洗浄した後、得られた有機層を濃縮した。濃縮物をｔｅｒｔ−ブチルメチルエーテル２４部でリパルプすることにより、白色固体として式（Ａ２）で表される化合物１．７部を得た。

16 parts of acetonitrile and 16 parts of ion-exchanged water were added to 5.4 parts (purity 35.6%) of the compound represented by the formula (A2-d). To the obtained mixture, 1.7 parts of the compound represented by the formula (A1-e), 5 parts of acetonitrile and 5 parts of ion-exchanged water were added. The resulting mixture was stirred for 15 hours and then concentrated, and the resulting mixture was extracted with 142 parts of chloroform to recover the organic layer. The collected organic layer was washed with ion-exchanged water, and then the obtained organic layer was concentrated. By repulping the concentrate with 24 parts of tert-butyl methyl ether, 1.7 parts of a compound represented by the formula (A2) was obtained as a white solid.

式（Ａ１−ａ）で表される化合物２００部及びイオン交換水３００部に、氷浴下、３０％水酸化ナトリウム水溶液４６０部を滴下した。得られた混合物を１００℃で２．５時間還流し、冷却した後、これを濃塩酸１７５部で中和した。得られた溶液を濃縮することにより式（Ａ１−ｂ）で表される化合物３２８．１９部（無機塩を除去していないため、含有量６３．５％）を得た。得られた式（Ａ１−ｂ）で表される化合物３９．４部（含有量６３．５％）、式（Ａ３−ｃ）で表される化合物２１．０部及びジクロロエタン２００部の混合物に、ｐ−トルエンスルホン酸（ｐ−ＴｓＯＨ）２４．０部を加え、これを７時間加熱還流した。その後、濃縮してジクロロエタンを留去し、濃縮残渣にｔｅｒｔ−ブチルメチルエーテル２５０部添加し、リパルプ後、濾過した。回収された濾過残渣にアセトニトリル２５０部を添加し、撹拌した後、濾過し、得られた濾液を濃縮することにより、式（Ａ３−ｄ）で表される化合物３２．８部を得た。

得られた式（Ａ３−ｄ）で表される化合物３２．８部を、イオン交換水１００部に溶解させた溶液に、式（Ａ１−ｅ）で表される化合物２８．３部及びメタノール１４０部溶液を添加した。得られた混合物を１５時間撹拌した後、濃縮し、得られた濃縮物をクロロホルム２００部で２回抽出した。２回の抽出により得られた回収された有機層を合せて、該有機層が中性になるまで、イオン交換水を用いた洗浄操作を繰り返し、その後、得られた有機層を濃縮した。濃縮液に、ｔｅｒｔ−ブチルメチルエーテル３００部を添加し、撹拌した後、濾過して白色析出物を回収し、これを減圧乾燥することにより白色結晶として式（Ａ３）で表される化合物３９．７部得た。 (Synthesis of acid generator A3)

To 200 parts of the compound represented by the formula (A1-a) and 300 parts of ion-exchanged water, 460 parts of a 30% aqueous sodium hydroxide solution was added dropwise in an ice bath. The resulting mixture was refluxed at 100 ° C. for 2.5 hours, cooled, and neutralized with 175 parts of concentrated hydrochloric acid. By concentrating the obtained solution, 328.19 parts of a compound represented by the formula (A1-b) (content of 63.5% because an inorganic salt was not removed) was obtained. In a mixture of 39.4 parts (content 63.5%) of the compound represented by the formula (A1-b) obtained, 21.0 parts of the compound represented by the formula (A3-c) and 200 parts of dichloroethane, 24.0 parts of p-toluenesulfonic acid (p-TsOH) was added, and this was heated to reflux for 7 hours. Thereafter, the mixture was concentrated to distill off dichloroethane, 250 parts of tert-butyl methyl ether was added to the concentrated residue, repulped and filtered. To the collected filtration residue, 250 parts of acetonitrile was added, stirred, filtered, and the obtained filtrate was concentrated to obtain 32.8 parts of a compound represented by the formula (A3-d).

In a solution obtained by dissolving 32.8 parts of the compound represented by the formula (A3-d) in 100 parts of ion-exchanged water, 28.3 parts of the compound represented by the formula (A1-e) and methanol 140 Part solution was added. The resulting mixture was stirred for 15 hours and then concentrated, and the resulting concentrate was extracted twice with 200 parts of chloroform. The recovered organic layers obtained by the extraction twice were combined, and the washing operation using ion-exchanged water was repeated until the organic layer became neutral, and then the obtained organic layer was concentrated. To the concentrate, 300 parts of tert-butyl methyl ether was added, stirred, and then filtered to collect a white precipitate, which was dried under reduced pressure to give compound 39. represented by the formula (A3) as white crystals. 7 parts were obtained.

式（Ａ１−ａ）で表される化合物２００部及びイオン交換水３００部に、氷浴下、３０％水酸化ナトリウム水溶液４６０部を滴下した。得られた混合物を１００℃で２．５時間還流し、冷却した後、これを濃塩酸１７５部で中和した。得られた溶液を濃縮することにより式（Ａ１−ｂ）で表される化合物３２８．１９部（無機塩を除去していないため、含有量６２．８％）を得た。得られた式（Ａ１−ｂ）で表される化合物１２３．３部（純度６２．８％）、式（Ａ３−ｃ）で表される化合物６５．７部及びジクロロエタン６００部の混合物に、ｐ−トルエンスルホン酸（ｐ−ＴｓＯＨ）７５．１部を加え、これを１２時間加熱還流した。その後、濃縮してジクロロエタンを留去し、濃縮残渣にｔｅｒｔ−ブチルメチルエーテル４００部を添加し、リパルプ後、濾過した。残渣にアセトニトリル４００部を添加し、撹拌後、ろ過を２回繰返し、濃縮することにより、式（Ａ３−ｄ）で表される化合物９９．５部を得た。 (Synthesis of acid generator A4)

To 200 parts of the compound represented by the formula (A1-a) and 300 parts of ion-exchanged water, 460 parts of a 30% aqueous sodium hydroxide solution was added dropwise in an ice bath. The resulting mixture was refluxed at 100 ° C. for 2.5 hours, cooled, and neutralized with 175 parts of concentrated hydrochloric acid. The obtained solution was concentrated to obtain 328.19 parts of a compound represented by the formula (A1-b) (the content was 62.8% because the inorganic salt was not removed). A mixture of 123.3 parts (purity 62.8%) of the compound represented by formula (A1-b), 65.7 parts of compound represented by formula (A3-c) and 600 parts of dichloroethane was added to p. -Toluenesulfonic acid (p-TsOH) 75.1 parts was added, and this was heated and refluxed for 12 hours. Thereafter, the mixture was concentrated to distill off dichloroethane, and 400 parts of tert-butyl methyl ether was added to the concentrated residue, followed by repulping and filtration. To the residue, 400 parts of acetonitrile was added, and after stirring, filtration was repeated twice and concentrated to obtain 99.5 parts of a compound represented by the formula (A3-d).

次いで、式（Ａ４−ｅ）で表される化合物１５０部をアセトン３７５部に溶解し、これに式（Ａ４−ｆ）で表される化合物６６．５部を滴下した。得られた混合物を室温で２４時間攪拌した後、生成した白色析出物をろ過して回収し、これをアセトンで洗浄し、次いで乾燥することにより白色結晶として式（Ａ４−ｇ）で表される化合物２０７．９部を得た。

Next, 150 parts of the compound represented by the formula (A4-e) was dissolved in 375 parts of acetone, and 66.5 parts of the compound represented by the formula (A4-f) were added dropwise thereto. The resulting mixture was stirred at room temperature for 24 hours, and then the produced white precipitate was collected by filtration, washed with acetone, and then dried to be represented by the formula (A4-g) as white crystals. 207.9 parts of compound were obtained.

先に得られた式（Ａ３−ｄ）で表される化合物９９．５部を、アセトニトリル２９８部に溶解させた。得られた溶液に、上記で得られた式（Ａ４−ｇ）で表される化合物７９．５部及びイオン交換水１５９部溶液を添加した。得られた混合物を１５時間撹拌した後、濃縮し、得られた濃縮物をクロロホルム５００部で２回抽出した。２回の抽出により回収された有機層を合せて、これをイオン交換水で洗浄し、得られた有機層を濃縮した。濃縮液に、ｔｅｒｔ−ブチルメチルエーテル２５０部を添加し、撹拌した後、ろ過して白色析出物を回収し、これを減圧乾燥することにより白色結晶として式（Ａ４）で表される化合物１１６．９部を得た。

99.5 parts of the compound represented by the formula (A3-d) obtained earlier was dissolved in 298 parts of acetonitrile. To the obtained solution, a solution of 79.5 parts of the compound represented by the formula (A4-g) obtained above and 159 parts of ion-exchanged water was added. The resulting mixture was stirred for 15 hours and then concentrated, and the resulting concentrate was extracted twice with 500 parts of chloroform. The organic layers recovered by the two extractions were combined, washed with ion-exchanged water, and the obtained organic layer was concentrated. To the concentrated solution, 250 parts of tert-butyl methyl ether was added, stirred, and then filtered to recover a white precipitate, which was dried under reduced pressure to give Compound 116. represented by the formula (A4) as white crystals. 9 parts were obtained.

リチウムアルミニウムハイドライド１０．４部、無水テトラヒドロフラン１２０部を仕込み２３℃で３０分間攪拌した。次いで、式（Ａ５−ａ）で表される化合物６２．２部を無水ＴＨＦ９００部に溶かした溶液を氷冷下で滴下し、２３℃で５時間攪拌した。反応マスに酢酸エチル５０．０部、６Ｎ塩酸５０．００部を添加、攪拌し、分液を行った。有機層を濃縮後、カラム（メルク シリカゲル６０−２００メッシュ 展開溶媒：クロロホルム／メタノール＝５／１）分取することにより、式（Ａ５−ｂ）で表される化合物８４．７ｇ（純度６０％）を得た。
また、式（Ａ５−ｃ）で表される化合物４．５部、無水ＴＨＦ９０部を添加し、室温で３０分間攪拌して溶解した。この溶液にカルボニルジイミダゾール３．７７部、無水ＴＨＦ４５部の混合溶液を室温で滴下し、２３℃で４時間攪拌した。得られた反応溶液を、（Ａ５−ｂ）７．８７部（純度６０％）、無水ＴＨＦ５０部の混合中に、５４℃〜６０℃にて３０分間で滴下した。反応溶液を６５℃で１８時間加熱し、冷却し、ろ過した。得られたろ液を濃縮し、濃縮物をカラム（メルク シリカゲル６０−２００メッシュ 展開溶媒：クロロホルム／メタノール＝５／１）分取することにより、式（Ａ５−ｄ）で表される化合物４．９７部を得た。 (Synthesis of acid generator A5)

10.4 parts of lithium aluminum hydride and 120 parts of anhydrous tetrahydrofuran were charged and stirred at 23 ° C. for 30 minutes. Next, a solution prepared by dissolving 62.2 parts of the compound represented by the formula (A5-a) in 900 parts of anhydrous THF was added dropwise under ice cooling, and the mixture was stirred at 23 ° C. for 5 hours. To the reaction mass, 50.0 parts of ethyl acetate and 50.00 parts of 6N hydrochloric acid were added, stirred, and separated. After concentrating the organic layer, by separating the column (Merck silica gel 60-200 mesh developing solvent: chloroform / methanol = 5/1), 84.7 g of compound represented by the formula (A5-b) (purity 60%) Got.
Further, 4.5 parts of the compound represented by the formula (A5-c) and 90 parts of anhydrous THF were added and dissolved by stirring for 30 minutes at room temperature. To this solution, a mixed solution of 3.77 parts of carbonyldiimidazole and 45 parts of anhydrous THF was added dropwise at room temperature, followed by stirring at 23 ° C. for 4 hours. The obtained reaction solution was added dropwise over 30 minutes at 54 ° C. to 60 ° C. while mixing 7.87 parts (purity 60%) of (A5-b) and 50 parts of anhydrous THF. The reaction solution was heated at 65 ° C. for 18 hours, cooled and filtered. The obtained filtrate was concentrated, and the concentrate was fractionated into a column (Merck silica gel 60-200 mesh developing solvent: chloroform / methanol = 5/1) to obtain a compound 4.97 represented by the formula (A5-d). Got a part.

次いで、式（Ａ５−ｄ）で表される化合物１．０部、クロロホルム２０部を仕込み、２３℃で３０分間攪拌し、更に式（Ａ１−ｅ）で表される化合物（１３．１％水溶液）６．３部を２３℃で加えた。１２時間室温で攪拌し、分液を行った。有機層にイオン交換水１０部を添加、分液水洗を行った。この操作を５回行った。その後、硫酸マグネシウム１部を添加、２３℃で３０分間攪拌し、ろ過し、ろ液を濃縮して、式（Ａ５）で表される化合物１．３６部を得た。

Next, 1.0 part of the compound represented by the formula (A5-d) and 20 parts of chloroform were charged, stirred at 23 ° C. for 30 minutes, and further the compound represented by the formula (A1-e) (13.1% aqueous solution). ) 6.3 parts were added at 23 ° C. The mixture was stirred for 12 hours at room temperature and separated. 10 parts of ion-exchanged water was added to the organic layer, followed by liquid separation washing. This operation was performed 5 times. Thereafter, 1 part of magnesium sulfate was added, stirred at 23 ° C. for 30 minutes, filtered, and the filtrate was concentrated to obtain 1.36 parts of a compound represented by the formula (A5).

リチウムアルミニウムハイドライド１０．４部、無水テトラヒドロフラン１２０部を仕込み２３℃で３０分間攪拌した。次いで、式（Ａ５−ａ）で表される化合物６２．２部を無水ＴＨＦ９００部に溶かした溶液を氷冷下で滴下し、２３℃で５時間攪拌した。反応マスに酢酸エチル５０．０部、６Ｎ塩酸５０．００部を添加、攪拌し、分液を行った。有機層を濃縮し、カラム（メルク シリカゲル６０−２００メッシュ 展開溶媒：クロロホルム／メタノール＝５／１）分取することにより、式（Ａ５−ｂ）で表される化合物を８４．７ｇ（純度６０％）を得た。
式（Ａ６−ｃ）で表される化合物３．５１部、無水ＴＨＦ７５部を仕込み２３℃で３０分間攪拌した。次いで、カルボニルジイミダゾール２．８９部、無水ＴＨＦ５０部の混合溶液を２３℃で滴下し、２３℃で４時間攪拌した。得られた反応液を、式（Ａ５−ｂ）で表される化合物６．０４部（純度６０％）、無水ＴＨＦ５０部の混合液中に５４〜６０℃で、２５分間で滴下し、６５℃で１８時間加熱し、冷却し、ろ過した。得られたろ液を濃縮し、濃縮物をカラム（メルク シリカゲル６０−２００メッシュ 展開溶媒：クロロホルム／メタノール＝５／１）分取することにより、式（Ａ６−ｄ）で表される化合物２．９９部を得た。

式（Ａ６−ｄ）で表される化合物１．０部、クロロホルム３０部を仕込み２３℃で３０分間攪拌した。次いで、式（Ａ１−ｅ）で表される化合物（１３．１％水溶液）６．３部を２３℃で１２時間攪拌し、分液を行った。有機層にイオン交換水１０部を添加、分液水洗を行った。この操作を３回行った。その後、硫酸マグネシウム１部を添加、２３℃で３０分間攪拌し、ろ過し、ろ液を濃縮して、式（Ａ６）で表される化合物１．６部を得た。

(Synthesis of acid generator A6)

10.4 parts of lithium aluminum hydride and 120 parts of anhydrous tetrahydrofuran were charged and stirred at 23 ° C. for 30 minutes. Next, a solution prepared by dissolving 62.2 parts of the compound represented by the formula (A5-a) in 900 parts of anhydrous THF was added dropwise under ice cooling, and the mixture was stirred at 23 ° C. for 5 hours. To the reaction mass, 50.0 parts of ethyl acetate and 50.00 parts of 6N hydrochloric acid were added, stirred, and separated. The organic layer was concentrated and fractionated by a column (Merck silica gel 60-200 mesh developing solvent: chloroform / methanol = 5/1) to obtain 84.7 g (purity 60%) of the compound represented by the formula (A5-b). )
3.51 parts of a compound represented by the formula (A6-c) and 75 parts of anhydrous THF were charged and stirred at 23 ° C. for 30 minutes. Next, a mixed solution of 2.89 parts of carbonyldiimidazole and 50 parts of anhydrous THF was added dropwise at 23 ° C., and the mixture was stirred at 23 ° C. for 4 hours. The obtained reaction solution was dropped in a mixed solution of 6.04 parts (purity 60%) of the compound represented by the formula (A5-b) and 50 parts of anhydrous THF at 25 to 60 ° C. over 25 minutes, and 65 ° C. For 18 hours, cooled and filtered. The obtained filtrate was concentrated, and the concentrate was fractionated into a column (Merck silica gel 60-200 mesh developing solvent: chloroform / methanol = 5/1) to obtain compound 2.99 represented by the formula (A6-d). Got a part.

1.0 part of a compound represented by the formula (A6-d) and 30 parts of chloroform were charged and stirred at 23 ° C. for 30 minutes. Next, 6.3 parts of the compound represented by the formula (A1-e) (13.1% aqueous solution) were stirred at 23 ° C. for 12 hours, and liquid separation was performed. 10 parts of ion-exchanged water was added to the organic layer, followed by liquid separation washing. This operation was performed three times. Thereafter, 1 part of magnesium sulfate was added, stirred at 23 ° C. for 30 minutes, filtered, and the filtrate was concentrated to obtain 1.6 parts of a compound represented by the formula (A6).

[Synthesis of Monomer E]
Charged 30.00 parts of 3,5-dihydroxy-1-adamantyl methacrylate (monomer H), 200.00 parts of tetrahydrofuran (THF), 43.58 parts of 4-dimethylaminopyridine (DMAP), and stirred at room temperature. Dissolved. To the mixture, 67.47 parts of di-tert-butyl dicarbonate was added dropwise and stirred at 40 ° C. for 5 hours. Further, 12.06 parts of concentrated hydrochloric acid was added. After stirring for 30 minutes, 400.00 parts of ethyl acetate was added and stirred for liquid separation. 100.00 parts of ion-exchanged water was added to the organic layer, followed by liquid separation washing, and further, a mixed solution of 12.06 parts of concentrated hydrochloric acid and 100.00 parts of ion-exchanged water was added to the organic layer for washing. Furthermore, the organic layer was separated and washed with 100.00 parts of ion-exchanged water, and the organic layer was concentrated. By separating the concentrated mass through a column (Kanto Kagaku Silica Gel 60N (spherical, neutral) 100-210 μm developing solvent: n-heptane / ethyl acetate = 5/1), 18.36 parts of monomer E (yield 34.12%) )
MASS: 452.2
¹ H-NMR (CDCL ₃ , internal standard substance tetramethylsilane): δ (ppm) 1.43 (s, 18H), 1.88 (s, 3H), 1.98-2.01 (m, 2H) 2.08-2.11 (m, 4H), 2.39-2.42 (m, 1H), 2.45-2.47 (m, 1H), 2.52-2.55 (m, 2H), 2.58-2.62 (m, 3H), 5.51 (m, 1H), 6.02 (s, 1H)

[Synthesis of Resin (B1)]
Monomer A, monomer E, monomer C and monomer D shown below were charged in a molar ratio of 40: 10: 20: 30, and then 1.5 times by weight of dioxane was added to the total amount of all monomers. To the resulting mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added as initiators at a ratio of 1 mol% and 3 mol%, respectively, with respect to the total number of moles of all monomers. This was heated at 72 ° C. for about 6 hours. Thereafter, the reaction solution is purified by pouring it into a large amount of methanol / water mixed solvent for precipitation three times to obtain a copolymer having a weight average molecular weight of about 9,600 in a yield of 62%. It was. The obtained copolymer has a structural unit derived from each monomer represented by the following formula, and this was designated as resin (B1).

[Synthesis of Resin (B2)]
Monomer G, monomer D and monomer F shown below were charged in a molar ratio of 30:50:20, and then 1.5 times by weight of dioxane was added to the total amount of all monomers. To the obtained mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 1 mol% and 3 mol%, respectively, based on the total number of moles of all monomers, 68 Heated at ℃ for about 6 hours. Thereafter, the reaction solution was purified by pouring it into a large amount of methanol / water mixed solvent and precipitating three times to obtain a copolymer having a weight average molecular weight of about 9,800 in a yield of 58%. . The obtained copolymer has a structural unit derived from each monomer of the following formula, and this was designated as resin (B2).

[Synthesis of Resin (B3)]
A resin was synthesized according to Resin Synthesis Example 1 of Patent Document 1.
The following monomer A, monomer B and monomer D were charged at a molar ratio of 50:25:25, and 1.5 times by weight of dioxane was added to the total amount of all monomers. To the obtained mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 1 mol% and 3 mol%, respectively, based on the total number of moles of all monomers, 68 Heated at ℃ for about 6 hours. Thereafter, the reaction solution was purified by pouring it into a large amount of methanol / water mixed solvent and precipitating three times to obtain a copolymer having a weight average molecular weight of about 10,000 in a yield of 65%. The obtained copolymer has a structural unit derived from a monomer of the following formula, and this was designated as resin (B3).

[Synthesis of Resin B4]
Monomer A, monomer D, monomer H and monomer J were charged in a molar ratio of 40: 25: 8: 27, and then 1.2 times by weight of dioxane was added to the total amount of all monomers. To the obtained mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 1 mol% and 3 mol%, respectively, based on the total number of moles of all monomers, Heated at 70 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a large amount of methanol / water mixed solvent and precipitating three times to obtain a copolymer having a weight average molecular weight of about 10,000 in a yield of 65%. . The obtained copolymer has a structural unit derived from each monomer of the following formula, and this was designated as resin (B4).

〔樹脂Ｂ５の合成〕
モノマーＧ、モノマーＩ、モノマーＢ、モノマーＥ、モノマーＤ及びモノマーＣを、モル比３０：１２：４：４：２０：３０の割合で仕込んだ。次いで、全モノマーの合計質量に対して、１．５質量倍のジオキサンを加えた。得られた混合物に、開始剤としてアゾビスイソブチロニトリルとアゾビス（２，４−ジメチルバレロニトリル）とを全モノマーの合計モル数に対して、それぞれ、１．００ｍｏｌ％と３．００ｍｏｌ％との割合で添加し、これを７５℃で約５時間加熱した。その後、反応液を、大量のメタノールと水との混合溶媒（４：１）に注いで沈殿させる操作を３回行うことにより精製し、重量平均分子量が約７．６×１０^３である共重合体を収率６０％で得た。この共重合体は、次式の構造単位を有するものであり、これを樹脂Ｂ５とする。

[Synthesis of Resin B5]
Monomer G, monomer I, monomer B, monomer E, monomer D and monomer C were charged in a molar ratio of 30: 12: 4: 4: 20: 30. Subsequently, 1.5 mass times dioxane was added with respect to the total mass of all the monomers. Into the obtained mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were respectively added to 1.00 mol% and 3.00 mol% with respect to the total number of moles of all monomers. And heated at 75 ° C. for about 5 hours. Thereafter, the reaction solution is purified by pouring it into a large amount of methanol / water mixed solvent (4: 1) and precipitating three times, and the weight average molecular weight is about 7.6 × 10 ^3. The coalescence was obtained in 60% yield. This copolymer has a structural unit of the following formula, and this is designated as resin B5.

Examples and Comparative Examples The following components were mixed and dissolved, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

<Acid generator>
C1: Triphenylsulfonium perfluorooctane sulfonate C2: 1- (2-oxo-2-phenylethyl) tetrahydrothiophenium perfluorobutane sulfonate C3: Triphenylsulfonium perfluorobutane sulfonate

<Quencher>
Q1: 2,6-diisopropylaniline Q2: triphenylimidazole Q3: triethanolamine <solvent>
Propylene glycol monomethyl ether acetate 265 parts 2-heptanone 20.0 parts Propylene glycol monomethyl ether 20.0 parts γ-butyrolactone 3.5 parts

An organic antireflective coating composition (ARC-29; manufactured by Nissan Chemical Co., Ltd.) is applied to a silicon wafer and baked at 205 ° C. for 60 seconds to form an organic antireflective coating having a thickness of 78 nm. Formed.
Subsequently, the resist composition was spin-coated on the organic antireflection film so that the film thickness after drying was 0.15 μm. After applying the resist composition, it was pre-baked on a direct hot plate at a temperature described in the “PB” column of Table 1 for 60 seconds.

For each wafer on which a resist film was formed in this way, an ArF excimer stepper (FPA5000-AS3; manufactured by Canon Inc., NA = 0.75, 2 / 3Annular) was used to change the exposure amount in stages. The space pattern was exposed.
After the exposure, post-exposure baking was performed for 60 seconds on the hot plate at the temperature described in the “PEB” column of Table 1 .
Further, paddle development was performed for 60 seconds with an aqueous 2.38 wt% tetramethylammonium hydroxide solution.
The dark field pattern after development on the organic antireflection film substrate was observed with a scanning electron microscope. The results are shown in Table 2.

The dark field pattern referred to here is obtained by exposure and development through a reticle having a glass surface (translucent portion) formed in a line form on the outside with a chromium layer (light-shielding layer) as a base, and thus exposure development. The rest is a pattern in which the resist layer around the line and space pattern is left.
Effective sensitivity: The exposure amount at which a 100 nm line and space pattern is 1: 1 is shown.

  Resolution evaluation: 100 nm line and space pattern was exposed at an exposure amount of 1: 1, the resist pattern was observed with a scanning electron microscope, and Comparative Example 1 was used as a reference (denoted by Δ). The image was judged as ◯, the case without change as Δ, and the case as deteriorated as X.

  Line edge roughness evaluation (LER): The surface of the resist pattern after the lithography process is observed with a scanning electron microscope, and Comparative Example 1 is used as a reference (indicated by Δ). The case where there was no smoothness was judged as Δ, and the case where it was not smooth was judged as ×.

  Pattern collapse evaluation: The resist pattern when the 100 nm line and space pattern was exposed at an exposure amount of 1: 1 was observed with a scanning electron microscope, and Comparative Example 1 was used as a reference (indicated by Δ). Were evaluated as ◯, those with no change as Δ, and those with many pattern collapses as X.

  According to the chemically amplified photoresist composition of the present invention, it is possible to form a pattern having excellent resolution and line edge roughness and in which pattern collapse does not occur.

Claims (18)

A chemically amplified photoresist composition containing an acid generator (A) and a resin (B),
The resin (B) is at least (b1) a structural unit that generates a carboxyl group by the action of an acid and becomes soluble in an alkaline developer,
(B2) comprising a structural unit containing an adamantyl group having at least two -OX ^a groups, and (b3) a structural unit derived from a monomer having a lactone ring,
X ^a in the structural unit (b2) represents a group capable of leaving by the action of an acid, and represents a tertiary aliphatic hydrocarbon group or a group containing a tertiary aliphatic hydrocarbon group. A chemically amplified photoresist composition. A chemically amplified photoresist composition containing an acid generator (A) and a resin (B),
The resin (B) is at least (b1) a structural unit that generates a carboxyl group by the action of an acid and becomes soluble in an alkaline developer,
(B2) a structural unit derived from a structural unit containing an adamantyl group having at least two —OX ^a groups (X ^a represents a group capable of leaving by the action of an acid), and (b3) a monomer having a lactone ring Comprising units and
A chemically amplified photoresist composition, wherein the acid generator contains an acid generator (A) represented by the formula (I).

(In Formula (I), Q < ¹ > and Q < ² > represent a fluorine atom or a C1-C6 perfluoroalkyl group mutually independently.
X ¹ represents a single bond or — [CH ₂ ] _k —, and the methylene group contained in — [CH ₂ ] _k — may be substituted with an oxygen atom or a carbonyl group, and the — [CH ₂ ] _The hydrogen atom contained in _k- may be substituted with a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms. k represents an integer of 1 to 17.
Y ¹ represents an alicyclic hydrocarbon group having 3 to 36 carbon atoms which may have a substituent, and the methylene group contained in the alicyclic hydrocarbon group is substituted with an oxygen atom or a carbonyl group. May be.
Z ⁺ represents an organic cation. )
X ^a in the structural unit (b2) represents ^a tertiary aliphatic hydrocarbon group, a group containing a tertiary aliphatic hydrocarbon group, or an alkoxyalkyl group, . The composition according to claim 1 or 2, wherein Xa in the structural unit (b2) is ^a linear, branched or cyclic tertiary aliphatic hydrocarbon group having 4 to 12 carbon atoms and having an ester bond. . The composition according to any one of claims 1 to 3, wherein Xa in the structural unit (b2) is ^a branched tertiary aliphatic hydrocarbon group having 4 to 7 carbon atoms having an ester bond. The composition according to any one of claims 1 to 4, wherein the structural unit (b2) comprises a structural unit represented by the formula (III).

[In Formula (III), R ¹ represents a hydrogen atom or a methyl group.
R ⁶ and R ⁷ each independently represent ^a hydrogen atom, a methyl group, a hydroxyl group, or an —OX ^a group, provided that at least one of R ⁶ and R ⁷ represents an —OX ^a group.
R ⁸ represents a methyl group.
X ^a represents a group capable of leaving by the action of an acid.
Z ″ represents a single bond or — [CH ₂ ] _{k ′} —, and the methylene group contained in — [CH ₂ ] _{k ′} — may be substituted with an oxygen atom or a carbonyl group. , Represents an integer of 1 to 17.
n ′ represents an integer of 0 to 10. ]   The monomer leading to the structural unit represented by formula (III) is 3,5-dihydroxy-1-adamantyl (meth) acrylate or 1- (3,5-dihydroxy-1-adamantyloxycarbonyl) methyl (meth) acrylate The composition according to claim 5, which is a monomer in which a hydrogen atom of the hydroxyl group is substituted with a linear, branched or cyclic tertiary aliphatic hydrocarbon group having an ester bond and having 4 to 12 carbon atoms. . The composition according to any one of claims 1 to 6, wherein the structural unit (b1) is a structural unit represented by the formula (Va) or the formula (Vc).

[In Formula (Va) and Formula (Vc), R ¹ represents a hydrogen atom or a methyl group.
R ² represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 10 carbon atoms.
R ³ represents a methyl group. n represents an integer of 0 to 14. n ′ represents an integer of 0 to 3.
Z ″ represents, independently of each other, a single bond or — [CH ₂ ] _{k ′} —, and the methylene group contained in — [CH ₂ ] _{k ′} — may be substituted with an oxygen atom or a carbonyl group. K ′ represents an integer of 1 to 17.]   Monomers leading to the structural unit represented by the formula (Va) are 2-methyl-2-adamantyl (meth) acrylate, 2-ethyl-2-adamantyl (meth) acrylate, 2-isopropyl-2-adamantyl (meth) acrylate And at least one selected from the group consisting of 1- (2-methyl-2-adamantyloxycarbonyl) methyl (meth) acrylate.   The composition according to claim 7, wherein the monomer that leads to the structural unit represented by the formula (Vc) is 1-ethyl-1-cyclohexyl (meth) acrylate. The composition according to any one of claims 1 to 9, wherein the structural unit (b3) is a structural unit derived from a monomer represented by any one of the formulas (IVa), (IVb), and (IVc). object.

[In Formula (IVa), Formula (IVb) and Formula (IVc), R ¹ represents a hydrogen atom or a methyl group.
R ⁹ represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. l represents an integer of 0 to 5.
R ¹⁰ and R ¹¹ each independently represent a carboxyl group, a cyano group, or a hydrocarbon group having 1 to 4 carbon atoms. l ′ and l ″ each independently represent an integer of 0 to 3. When l ′ and l ″ are 2 or more, the plurality of R ¹⁰ and R ¹¹ may be the same as or different from each other.
Z ″ represents a single bond or — [CH ₂ ] _{k ′} —, and the methylene group contained in — [CH ₂ ] _{k ′} — may be substituted with an oxygen atom or a carbonyl group. Represents an integer of 1 to 17.] The composition according to any one of claims 1, 3 to 10, wherein the acid generator contains an acid generator (A) represented by the formula (I).

(In Formula (I), Q < ¹ > and Q < ² > represent a fluorine atom or a C1-C6 perfluoroalkyl group mutually independently.
X ¹ represents a single bond or — [CH ₂ ] _k —, and the methylene group contained in — [CH ₂ ] _k — may be substituted with an oxygen atom or a carbonyl group, and the — [CH ₂ ] _The hydrogen atom contained in _k- may be substituted with a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms. k represents an integer of 1 to 17.
Y ¹ represents an alicyclic hydrocarbon group having 3 to 36 carbon atoms which may have a substituent, and the methylene group contained in the alicyclic hydrocarbon group is substituted with an oxygen atom or a carbonyl group. May be.
Z ⁺ represents an organic cation. ) The composition according to claim 2 or 11, wherein Y ¹ in the formula (I) is a group represented by the formula (Y1).

[In Formula (Y1), Ring W represents an alicyclic hydrocarbon group having 3 to 36 carbon atoms, and the methylene group contained in the alicyclic hydrocarbon group is substituted with an oxygen atom or a carbonyl group. Also good.
R ^a represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms.
R ^b is independently of each other a halogen atom, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 21 carbon atoms. Represents a glycidoxy group or an acyl group having 2 to 4 carbon atoms.
x represents an integer of 0 to 8. When x is 2 or more, the plurality of R ^b may be the same or different. ]   The composition according to claim 12, wherein the ring W has at least one structure selected from the group consisting of an adamantyl group, an oxo-adamantyl group, and a cyclohexyl group. The composition according to any one of claims 2 to 13 , wherein the acid generator (A) contains an acid generator in which Z ⁺ is an arylsulfonium cation.   The composition according to any one of claims 1 to 14, wherein the content of the acid generator (A) is 1 to 20 parts by mass with respect to 100 parts by mass of the total amount of the resin (B).   Furthermore, the composition as described in any one of Claims 1-15 containing a nitrogen-containing basic compound.   The composition according to claim 16, wherein the nitrogen-containing basic compound is diisopropylaniline. (1) The process of apply | coating the chemical amplification type photoresist composition in any one of Claims 1-17 on a board | substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) A pattern forming method comprising a step of developing the heated composition layer using a developing device.