JP7114242B2 - RESIST COMPOSITION AND RESIST PATTERN MANUFACTURING METHOD - Google Patents

Description

The present invention relates to a resist composition and a method for producing a resist pattern using the resist composition.

Patent Document 1 describes a resist composition containing a compound having the following structural formula, a resin containing a structural unit having an acid-labile group, and an acid generator.

JP-A-11-24274

The line edge roughness (LER) of the resist composition using the above compound was not necessarily satisfactory in some cases.

［式（Ｉ）中、
Ｒ^１は、置換基を有していてもよい炭素数１～２４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に置き換わっていてもよい。
Ｒ^２は、水素原子又は炭素数１～６のアルキル基を表す。
Ａｒは、置換基を有していてもよい炭素数６～２４の２価の芳香族炭化水素基を表す。］
〔２〕Ｒ^１が、置換基を有していてもよい炭素数６～２４の芳香族炭化水素基又はＲ^３－（Ｏ）_ｎ－ＣＯ－＊（式中、ｎは０又は１を表す。＊はNとの結合位を表す。Ｒ^３は、置換基を有していてもよい炭素数１～２２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に置き換わっていてもよい。）で表される基である〔１〕記載のレジスト組成物。
〔３〕Ｒ^２が、水素原子である〔１〕又は〔２〕記載のレジスト組成物。
〔４〕酸発生剤から発生する酸よりも酸性度の弱い酸を発生する塩をさらに含有する〔１〕～〔３〕のいずれかに記載のレジスト組成物。
〔５〕（１）〔１〕～〔４〕のいずれかに記載のレジスト組成物を基板上に塗布する工程、
（２）塗布後の組成物を乾燥させて組成物層を形成する工程、
（３）組成物層に露光する工程、
（４）露光後の組成物層を加熱する工程、及び
（５）加熱後の組成物層を現像する工程を含むレジストパターンの製造方法。 The present invention includes the following inventions.
[1] A resist composition containing a compound represented by formula (I), a resin having an acid-labile group, and an acid generator.

[in the formula (I),
R ¹ represents an optionally substituted hydrocarbon group having 1 to 24 carbon atoms, and the methylene group contained in the hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
Ar represents an optionally substituted divalent aromatic hydrocarbon group having 6 to 24 carbon atoms. ]
[2] R ¹ is an optionally substituted aromatic hydrocarbon group having 6 to 24 carbon atoms or R ³ —(O) _n —CO—* (wherein n represents 0 or 1 * represents the bonding position with N. R ³ represents a hydrocarbon group having 1 to 22 carbon atoms which may have a substituent, and the methylene group contained in the hydrocarbon group is an oxygen atom or (which may be substituted with a carbonyl group).
[3] The resist composition according to [1] or [2], wherein ^R2 is a hydrogen atom.
[4] The resist composition according to any one of [1] to [3], further comprising a salt that generates an acid weaker in acidity than the acid generated from the acid generator.
[5] (1) a step of applying the resist composition according to any one of [1] to [4] onto a substrate;
(2) a step of drying the applied composition to form a composition layer;
(3) exposing the composition layer;
(4) A process of heating the composition layer after exposure, and (5) a process of developing the composition layer after heating.

By using the resist composition of the present invention, a resist pattern with good line edge roughness (LER) can be produced.

As used herein, "(meth)acrylate" means "at least one of acrylate and methacrylate". Notations such as "(meth)acrylic acid" and "(meth)acryloyl" have the same meaning.
In addition, unless otherwise specified, a group that can be linear, branched and/or cyclic such as an "aliphatic hydrocarbon group" includes any of them. The "aromatic hydrocarbon group" also includes groups in which a hydrocarbon group is bonded to an aromatic ring. Where stereoisomers exist, all stereoisomers are included.
As used herein, "the solid content of the resist composition" means the total amount of components excluding the solvent (E) described below from the total amount of the resist composition.

<Resist composition>
The resist composition of the present invention comprises a compound represented by formula (I) (hereinafter sometimes referred to as "compound (I)") and a resin containing a structural unit having an acid-labile group (hereinafter referred to as "resin (A) ”) and an acid generator (hereinafter sometimes referred to as “acid generator (B)”).
The "acid-labile group" here has a leaving group, and upon contact with an acid, the leaving group is eliminated and converted into a structural unit having a hydrophilic group (e.g., hydroxy group or carboxy group). means the base.
In addition to the compound (I), the resin (A) and the acid generator (B), the resist composition of the present invention further comprises a quencher (hereinafter sometimes referred to as "quencher (C)") and/or a solvent ( hereinafter sometimes referred to as "solvent (E)").

［式（Ｉ）中、
Ｒ^１は、置換基を有していてもよい炭素数１～２４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に置き換わっていてもよい。
Ｒ^２は、水素原子又は炭素数１～６のアルキル基を表す。
Ａｒは、置換基を有していてもよい炭素数６～２４の２価の芳香族炭化水素基を表す。］ <Compound (I)>
The resist composition of the present invention contains compound (I).

[in the formula (I),
R ¹ represents an optionally substituted hydrocarbon group having 1 to 24 carbon atoms, and the methylene group contained in the hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
Ar represents an optionally substituted divalent aromatic hydrocarbon group having 6 to 24 carbon atoms. ]

The hydrocarbon group represented by R ¹ includes an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a group combining these groups, and the like.
Aliphatic hydrocarbon groups include alkyl groups, alkenyl groups and alkynyl groups, methyl groups, ethyl groups, propyl groups, isopropyl groups, butyl groups, isobutyl groups, tert-butyl groups, pentyl groups, hexyl groups and octyl groups. Alkyl groups such as nonyl groups are preferred. The number of carbon atoms in the aliphatic hydrocarbon group is preferably 1-9, more preferably 3-8.
Alicyclic hydrocarbon groups can be monocyclic or polycyclic (including bridged rings, spirocycles and ring assemblies), and can be saturated or unsaturated. The alicyclic hydrocarbon group includes monocyclic groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclononyl, cyclodecyl, cyclododecyl, methylcyclohexyl and methylcyclopentyl groups. Cycloalkyl group; group in which two or more cycloalkyl groups are condensed (e.g., bridged rings such as norbornyl group, adamantyl group, methyladamantyl group, ethyladamantyl group), spiro ring (e.g., cycloalkyl such as spirodecyl group and cyclo spirocyclic group with alkyl, spirocyclic group with cycloalkyl and adamantyl, dispirotetradecyl group, etc.), polycyclic cycloalkyl group with ring assembly (eg, bicyclopentyl group, etc.), and the like. The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms, more preferably 3 to 12 carbon atoms, and still more preferably 3 to 10 carbon atoms.
Aromatic hydrocarbon groups include aryl groups such as a phenyl group, 1-naphthyl group, 2-naphthyl group, anthonyl group, biphenyl group, anthryl group, phenanthryl group, and binaphthyl group; 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-propylphenyl group, 4-isopropylphenyl group, 4-butylphenyl group, 4-tert-butylphenyl group, 4-hexylphenyl group, tolyl group, xylyl Alkyl-aryl groups such as group, cumenyl group, mesityl group, 2,6-diethylphenyl group and 2-methyl-6-ethylphenyl group; cycloalkyl-aryl groups such as 4-cyclohexylphenyl group and p-adamantylphenyl group; are mentioned. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6-14, more preferably 6-10.
Groups in which aliphatic hydrocarbon groups, alicyclic hydrocarbon groups and aromatic hydrocarbon groups are combined include cycloalkyl-alkyl groups (adamantylmethyl group, adamantylethyl group, cyclohexylmethyl group, cyclopentylmethyl group), aralkyl groups (For example, phenylmethyl group, 1-phenylethyl group, 2-phenylethyl group, 1-phenyl-1-propyl group, 1-phenyl-2-propyl group, 2-phenyl-2-propyl group, 3-phenyl- 1-propyl group, 4-phenyl-1-butyl group, 5-phenyl-1-pentyl group, 6-phenyl-1-hexyl group, etc.) and the like.

Substituents which the hydrocarbon group represented by R ¹ may have include a hydroxy group, a nitro group, a halogen atom, an alkoxy group having 1 to 12 carbon atoms, and a carboxyl group. Among them, a hydroxy group, a nitro group, a halogen atom or an alkoxy group having 1 to 12 carbon atoms is preferable, and a hydroxy group and a halogen atom are more preferable.
Halogen atoms include fluorine, chlorine, bromine, and iodine atoms.
Examples of alkoxy groups having 1 to 12 carbon atoms include methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, octyloxy, 2-ethylhexyloxy, nonyloxy, decyloxy, and undecyloxy. group, dodecyloxy group, and the like.

Alkyl groups represented by R ² include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group and n-hexyl group. and preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group.

The divalent aromatic hydrocarbon group for Ar includes divalent aryl groups such as a phenylene group, naphthylene group, biphenylene group, anthrylene group, phenanthrylene group, binaphthylene group, tolylene group, xylylene group, and p-adamantylphenylene group. is mentioned. The number of carbon atoms in the divalent aromatic hydrocarbon group is preferably 6-14, more preferably 6-10.

Substituents which the divalent aromatic hydrocarbon group of Ar may have include a hydroxy group, a nitro group, a halogen atom, a cyano group, an alkoxy group having 1 to 12 carbon atoms, and a carboxyl group. Among them, a hydroxy group, a nitro group, a halogen atom, a cyano group or an alkoxy group having 1 to 12 carbon atoms is preferable.
Examples of alkoxy groups having 1 to 12 carbon atoms include methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, octyloxy, 2-ethylhexyloxy, nonyloxy, decyloxy, and undecyloxy. group, dodecyloxy group, and the like.

When the aromatic hydrocarbon group for R ¹ is an alkyl-aryl group, the alkyl group is preferably an alkyl group having 1 to 12 carbon atoms, such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, 2-ethylhexyl group, nonyl group and the like.
When the aromatic hydrocarbon group for R ¹ is a cycloalkyl-aryl group, the cycloalkyl group may be either monocyclic or polycyclic, and includes the groups shown below and cyclohexylcyclohexyl groups. * represents a bond with a ring.

R ¹ is preferably an optionally substituted aromatic hydrocarbon group having 6 to 24 carbon atoms or R ³ —(O) _n —CO—* (wherein n represents 0 or 1 * represents the bonding position with N. R ³ represents an optionally substituted hydrocarbon group having 1 to 22 carbon atoms, and the methylene group contained in the hydrocarbon group is an oxygen atom or may be substituted with a carbonyl group).
The hydrocarbon group represented by R ³ includes an aliphatic hydrocarbon group (the methylene group contained in the aliphatic hydrocarbon group may be replaced with an oxygen atom or a carbonyl group), an alicyclic hydrocarbon group (the methylene group contained in the alicyclic hydrocarbon group may be replaced with an oxygen atom or a carbonyl group), an aromatic hydrocarbon group, a combination of these groups, and the like.
Examples of R ³ —(O) _n —CO—* include the groups represented below.

R ² is preferably a hydrogen atom.
R ¹ is preferably an optionally substituted aromatic hydrocarbon group having 6 to 24 carbon atoms or a group represented by R ³ —(O) _n —CO-*, and R ³ — (O) _n —CO—* and R ³ is an optionally substituted alicyclic hydrocarbon group (the methylene group contained in the alicyclic hydrocarbon group is an oxygen atom or a carbonyl group is more preferably R ³ —(O) _n —CO—*, and R ³ is one or more substituents selected from the group consisting of a hydroxy group and a halogen atom or an alicyclic hydrocarbon group in which at least one methylene group is replaced by an oxygen atom or a carbonyl group.
Ar is preferably a phenylene group optionally having a substituent. Substituents for the phenylene group include a hydroxy group, a nitro group, a halogen atom, a cyano group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and an alicyclic hydrocarbon group having 3 to 12 carbon atoms. , an aromatic hydrocarbon group having 6 to 10 carbon atoms or a carboxyl group. Among them, a hydroxy group, a nitro group, a halogen atom, a cyano group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms is preferable.

Compound (I) includes compounds represented by the following formula.

<Method for producing compound (I)>
Compounds represented by formula (I) include compounds represented by the following formulas, etc., which are readily available on the market.

［式中、Ｒ^２、Ｒ^３及びＡｒは、上記と同義である。］ R ¹ is R ³ —O—CO-* (where * represents the bonding position with N; R ³ represents a hydrocarbon group having 1 to 22 carbon atoms which may have a substituent; , the methylene group contained in the hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.) The compound represented by the formula (I2) is represented by the formula (I2-a) It can be obtained by reacting the compound represented by Formula (I2-b) with the compound represented by Formula (I2-b) in the presence of a catalyst in a solvent.

[In the formula, R ² , R ³ and Ar are as defined above. ]

式（Ｉ２－ｂ）で表される化合物としては、下記式で表される化合物等が挙げられ、市場より容易に入手することができる。

Catalysts include carbonyldiimidazole and the like.
Solvents include chloroform, monochlorobenzene, tetrahydrofuran and toluene.
The reaction temperature is generally 10° C. to 80° C., and the reaction time is generally 0.5 hours to 25 hours.
Examples of the compound represented by formula (I2-a) include compounds represented by the following formula, etc., which are readily available on the market.

Examples of the compound represented by formula (I2-b) include compounds represented by the following formula, etc., which are readily available on the market.

R ¹ is R ³ -CO-* (wherein * represents the bonding position with N; R ³ represents a hydrocarbon group having 1 to 22 carbon atoms which may have a substituent; The methylene group contained in the hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.) The compound represented by formula (I3), which is a group represented by formula (I3-a) and a compound represented by formula (I3-b) in the presence of a base catalyst in a solvent.

式（Ｉ３－ｂ）で表される化合物としては、下記式で表される化合物等が挙げられ、市場より容易に入手することができる。

Base catalysts include pyridine and the like.
Examples of solvents include tetrahydrofuran and toluene.
The reaction temperature is generally 0° C. to 80° C., and the reaction time is generally 0.5 hours to 24 hours.
Examples of the compound represented by formula (I3-a) include compounds represented by the following formula, etc., which are readily available on the market.

Examples of the compound represented by formula (I3-b) include compounds represented by the following formula, etc., which are readily available on the market.

The content of compound (I) is usually 0.001 to 20% by mass, preferably 0.005 to 15% by mass, more preferably 0.01 to 10% by mass, based on the solid content of the resist composition. .
Compound (I) functions as a quencher in the resist composition.

<Resin (A)>
Resin (A) has a structural unit having an acid-labile group (hereinafter sometimes referred to as "structural unit (a1)"). The resin (A) preferably further contains structural units other than the structural unit (a1). Structural units other than the structural unit (a1) include structural units having no acid-labile group (hereinafter sometimes referred to as "structural unit (s)").

［式（１）中、Ｒ^a1～Ｒ^a3は、それぞれ独立に、炭素数１～８のアルキル基、炭素数３～２０の脂環式炭化水素基又はこれらを組み合わせた基を表すか、Ｒ^a1及びＲ^a2は互いに結合してそれらが結合する炭素原子とともに炭素数３～２０の２価の脂環式炭化水素基を形成する。
ｍａ及びｎａは、それぞれ独立して、０又は１を表し、ｍａ及びｎａの少なくとも一方は１を表す。
＊は結合手を表す。］

［式（２）中、Ｒ^a1’及びＲ^a2’は、それぞれ独立に、水素原子又は炭素数１～１２の炭化水素基を表し、Ｒ^a3’は、炭素数１～２０の炭化水素基を表すか、Ｒ^a2’及びＲ^a3’は互いに結合してそれらが結合する炭素原子及びＸとともに炭素数３～２０の２価の複素環基を形成し、該炭化水素基及び該２価の複素環基に含まれる－ＣＨ₂－は、－Ｏ－又は－Ｓ－で置き換わってもよい。
Ｘは、酸素原子又は硫黄原子を表す。
ｎａ’は、０又は１を表す。
＊は結合手を表す。］ <Structural unit (a1)>
The structural unit (a1) is derived from a monomer having an acid-labile group (hereinafter sometimes referred to as "monomer (a1)").
The acid-labile group contained in the resin (A) is preferably a group represented by formula (1) and/or a group represented by formula (2).

[In formula (1), R ^a1 to R ^a3 each independently represent an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a group combining these; ^a1 and R ^a2 are bonded to each other to form a divalent alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded.
ma and na each independently represent 0 or 1, and at least one of ma and na represents 1;
* represents a bond. ]

[In formula (2), R ^a1′ and R ^a2′ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R ^a3′ represents a hydrocarbon group having 1 to 20 carbon atoms. or R ^a2′ and R ^a3′ are bonded to each other to form a divalent heterocyclic group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X, and the hydrocarbon group and the divalent heterocyclic --CH ₂ -- contained in the ring group may be replaced with --O-- or --S--.
X represents an oxygen atom or a sulfur atom.
na' represents 0 or 1;
* represents a bond. ]

アルキル基と脂環式炭化水素基とを組み合わせた基としては、例えば、シクロヘキシルメチル基、アダマンチルメチル基、アダマンチルジメチル基、ノルボルニルエチル基等のシクロアルキル－アルキル基が挙げられる。
好ましくは、ｍａは０であり、ｎａは１である。
Ｒ^a1及びＲ^a2が互いに結合して２価の脂環式炭化水素基を形成する場合の－Ｃ（Ｒ^a1）（Ｒ^a2）（Ｒ^a3）としては、下記の基が挙げられる。２価の脂環式炭化水素基は、好ましくは炭素数３～１２である。＊は－Ｏ－との結合手を表す。

Examples of alkyl groups of R ^a1 to R ^a3 include methyl group, ethyl group, propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group and n-octyl group.
The alicyclic hydrocarbon groups of R ^a1 to R ^a3 may be monocyclic, polycyclic or spirocyclic, and may be saturated or unsaturated. The monocyclic alicyclic hydrocarbon group includes cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, methylcyclohexyl group, dimethylcyclohexyl group and methylnorbornyl group. mentioned. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl group, adamantyl group, norbornyl group, adamantylcyclohexyl group and the following groups (* represents a bond). The alicyclic hydrocarbon groups of R ^a1 to R ^a3 preferably have 3 to 16 carbon atoms.

Groups in which an alkyl group and an alicyclic hydrocarbon group are combined include, for example, cycloalkyl-alkyl groups such as cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group and norbornylethyl group.
Preferably, ma is 0 and na is 1.
Examples of —C(R ^a1 )(R ^a2 )(R ^a3 ) when R ^a1 and R ^a2 combine to form a divalent alicyclic hydrocarbon group include the following groups. The divalent alicyclic hydrocarbon group preferably has 3-12 carbon atoms. * represents a bond with -O-.

Ｒ^a1'及びＲ^a2'のうち、少なくとも１つは水素原子であることが好ましい。
ｎａ’は、好ましくは０である。 Examples of the hydrocarbon groups of R ^a1′ to R ^a3′ include alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups and groups formed by combining these groups.
Examples of the alkyl group and the alicyclic hydrocarbon group are the same as those described above.
Aromatic hydrocarbon groups include phenyl, naphthyl, anthryl, biphenyl, phenanthryl and other aryl groups, tolyl, xylyl, cumenyl, mesityl, p-tert-butylphenyl, 2,6 Alkyl-aryl groups such as -diethylphenyl group and 2-methyl-6-ethylphenyl group; cycloalkyl-aryl groups such as p-adamantylphenyl group;
Groups in which alkyl groups, alicyclic hydrocarbon groups and aromatic hydrocarbon groups are combined include cycloalkyl-alkyl groups (adamantylmethyl group, adamantylethyl group, cyclohexylmethyl group, cyclopentylmethyl group), aralkyl groups (e.g., phenylmethyl group, 1-phenylethyl group, 2-phenylethyl group, 1-phenyl-1-propyl group, 1-phenyl-2-propyl group, 2-phenyl-2-propyl group, 3-phenyl-1-propyl group, 4-phenyl-1-butyl group, 5-phenyl-1-pentyl group, 6-phenyl-1-hexyl group, etc.) and the like.
-C(R ^a1' )(R ^a3' )-X-R ^a2' when R ^a2' and R ^a3' are bonded to each other to form a divalent heterocyclic group together with the carbon atom to which they are bonded and X; Examples include the following groups. * represents a bond.

At least one of R ^a1′ and R ^a2′ is preferably a hydrogen atom.
na' is preferably zero.

The group represented by formula (1) includes a 1,1-dialkylalkoxycarbonyl group (in formula (1), R ^a1 to R ^a3 are alkyl groups, ma = 0, na = 1, preferably tert-butoxycarbonyl group), 2-alkyladamantan-2-yloxycarbonyl group (in formula (1), R ^a1 , R ^a2 and the carbon atom to which they are bonded are an adamantyl group, R ^a3 is an alkyl group, ma = 0, na = 1 ) and a 1-(adamantan-1-yl)-1-alkylalkoxycarbonyl group (in formula (1), R ^a1 and R ^a2 are alkyl groups, R ^a3 is an adamantyl group, ma = 0, na = 1), etc. Furthermore, the following groups are mentioned. * represents a bond.

Specific examples of the group represented by formula (2) include the following groups. * represents a bond.

Monomer (a1) is preferably a monomer having an acid labile group and an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer having an acid labile group.

Among (meth)acrylic monomers having an acid-labile group, those having an alicyclic hydrocarbon group having 5 to 20 carbon atoms are preferred. When the resin (A) having a structural unit derived from the monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved.

［式（ａ１－０）、式（ａ１－１）及び式（ａ１－２）中、
Ｌ^a01、Ｌ^ａ１及びＬ^ａ２は、それぞれ独立に、－Ｏ－又は^＊－Ｏ－（ＣＨ_２）_ｋ１－ＣＯ－Ｏ－を表し、ｋ１は１～７のいずれかの整数を表し、＊は－ＣＯ－との結合手を表す。
Ｒ^a01、Ｒ^ａ４及びＲ^ａ５は、それぞれ独立に、水素原子又はメチル基を表す。
Ｒ^a02、Ｒ^a03及びＲ^a04は、それぞれ独立に、炭素数１～８のアルキル基、炭素数３～１８の脂環式炭化水素基又はこれらを組み合わせた基を表す。
Ｒ^ａ６及びＲ^ａ７は、それぞれ独立に、炭素数１～８のアルキル基、炭素数３～１８の脂環式炭化水素基又はこれらを組合せることにより形成される基を表す。
ｍ１は０～１４のいずれかの整数を表す。
ｎ１は０～１０のいずれかの整数を表す。
ｎ１’は０～３のいずれかの整数を表す。］ As a structural unit derived from a (meth)acrylic monomer having a group represented by formula (1), a structural unit represented by formula (a1-0) (hereinafter referred to as structural unit (a1-0)) is preferable. ), a structural unit represented by formula (a1-1) (hereinafter sometimes referred to as structural unit (a1-1)), or a structural unit represented by formula (a1-2) (hereinafter referred to as may be referred to as a structural unit (a1-2)). These may be used alone or in combination of two or more.

[In formula (a1-0), formula (a1-1) and formula (a1-2),
L ^a01 , L ^a1 and L ^a2 each independently represent —O— or ^* —O—(CH ₂ ) _k1 —CO—O—, k1 represents an integer of 1 to 7, * is represents a bond with -CO-.
R ^a01 , R ^a4 and R ^a5 each independently represent a hydrogen atom or a methyl group.
R ^a02 , R ^a03 and R ^a04 each independently represent an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a combination thereof.
R ^a6 and R ^a7 each independently represent an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining these.
m1 represents any integer from 0 to 14;
n1 represents any integer from 0 to 10;
n1' represents an integer of 0 to 3; ]

R ^a01 , R ^a4 and R ^a5 are preferably methyl groups.
L ^a01 , L ^a1 and L ^a2 are preferably an oxygen atom or *—O—(CH ₂ ) _k01 —CO—O— (provided that k01 is preferably any integer of 1 to 4, more preferably is 1.), more preferably an oxygen atom.
R ^a02 , R ^a03 , R ^a04 , R ^a6 and R ^a7 as alkyl groups, alicyclic hydrocarbon groups and groups in which these groups are combined are the same as the groups listed for R ^a1 to R ^a3 in formula (1). groups.
The number of carbon atoms in the alkyl groups of R ^a02 , R ^a03 , R ^a04 , R ^a6 and R ^a7 is preferably 1 to 6, more preferably methyl or ethyl, still more preferably methyl.
The alicyclic hydrocarbon groups of R ^a02 , R ^a03 , R ^a04 , R ^a6 and R ^a7 preferably have 3 to 8 carbon atoms, more preferably 3 to 6 carbon atoms.
It is preferable that the combined group of an alkyl group and an alicyclic hydrocarbon group have a total carbon number of 18 or less.
R ^a02 and R ^a03 are preferably alkyl groups having 1 to 6 carbon atoms, more preferably methyl or ethyl groups.
R ^a04 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 12 carbon atoms, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group.
m1 is preferably an integer from 0 to 3, more preferably 0 or 1.
n1 is preferably an integer from 0 to 3, more preferably 0 or 1.
n1' is preferably 0 or 1.

As the structural unit (a1-0), for example, a structural unit represented by any one of formulas (a1-0-1) to (a1-0-12) and a methyl group corresponding to R ^a01 is a hydrogen atom. Substituted structural units are included, and structural units represented by any one of formulas (a1-0-1) to (a1-0-10) are preferred.

Examples of the monomer leading to the structural unit (a1-1) include monomers described in JP-A-2010-204646. Among them, a structural unit represented by any one of formulas (a1-1-1) to (a1-1-4) and a structural unit in which a methyl group corresponding to R ^a4 is replaced with a hydrogen atom are preferable, and the structural unit represented by formula (a1 -1-1) to a structural unit represented by any one of formulas (a1-1-4) is more preferred.

As the structural unit (a1-2), a structural unit represented by any one of formulas (a1-2-1) to (a1-2-6) and a methyl group corresponding to R ^a5 are replaced with hydrogen atoms. Structural units may be mentioned, and formulas (a1-2-2), (a1-2-5) and (a1-2-6) are preferred.

When the resin (A) contains the structural unit (a1-0) and/or the structural unit (a1-1) and/or the structural unit (a1-2), the total content of these is the total structure of the resin (A) It is generally 10 to 95 mol %, preferably 15 to 90 mol %, more preferably 20 to 85 mol %, relative to the unit.

式（ａ１－５）中、
Ｒ^a8は、ハロゲン原子を有していてもよい炭素数１～６のアルキル基、水素原子又はハロゲン原子を表す。
Ｚ^a1は、単結合又は＊－（ＣＨ₂）_h3－ＣＯ－Ｌ⁵⁴－を表し、ｈ３は１～４のいずれかの整数を表し、＊は、Ｌ⁵¹との結合手を表す。
Ｌ⁵¹、Ｌ⁵²、Ｌ⁵³及びＬ⁵⁴は、それぞれ独立に、－Ｏ－又は－Ｓ－を表す。
ｓ１は、１～３のいずれかの整数を表す。
ｓ１’は、０～３のいずれかの整数を表す。 As the structural unit derived from a (meth)acrylic monomer having a group represented by formula (2), a structural unit represented by formula (a1-5) (hereinafter referred to as "structural unit (a1-5)" There is) is also mentioned.

In formula (a1-5),
R ^a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
Z ^a1 represents a single bond or *—(CH ₂ ) _h3 —CO—L ⁵⁴ —, h3 represents an integer of 1 to 4, and * represents a bond with L ⁵¹ .
L ⁵¹ , L ⁵² , L ⁵³ and L ⁵⁴ each independently represent -O- or -S-.
s1 represents any integer from 1 to 3;
s1′ represents any integer from 0 to 3;

Halogen atoms include fluorine atoms and chlorine atoms, with fluorine atoms being preferred.
Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, fluoromethyl group and trifluoro A methyl group is mentioned.
In formula (a1-5), R ^a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group.
L ⁵¹ is preferably an oxygen atom.
Preferably, one of L ⁵² and L ⁵³ is —O— and the other is —S—.
As for s1, 1 is preferable.
s1' is preferably an integer of 0-2.
Z ^a1 is preferably a single bond or *—CH ₂ —CO—O—.

Examples of the monomer leading to the structural unit (a1-5) include monomers described in JP-A-2010-61117. Among them, structural units represented by formulas (a1-5-1) to (a1-5-4) are preferable, and represented by formula (a1-5-1) or formula (a1-5-2) Structural units are more preferred.

When the resin (A) has the structural unit (a1-5), the content thereof is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, based on the total structural units of the resin (A). , 5 to 40 mol % is more preferable.

The structural unit (a1) also includes the following structural units.

樹脂（Ａ）が上記構造単位を含む場合、その含有率は、樹脂（Ａ）の全構造単位に対して、１０～９５モル％が好ましく、１５～９０モル％がより好ましく、２０～８５モル％がさらに好ましい。

When the resin (A) contains the above structural unit, its content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, and 20 to 85 mol, based on the total structural units of the resin (A). % is more preferred.

<Structural unit (s)>
The resin (A) further includes a structural unit having no acid-labile group (hereinafter sometimes referred to as "structural unit (s)") and a structural unit having a halogen atom (hereinafter sometimes referred to as "structural unit ( a4)”), a structural unit (a5) having a non-leaving hydrocarbon group, and a structural unit derived from other known monomers. Among them, it is preferable that the structural unit (s) is included. Structural unit (s) is derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer (s)"). As the monomer (s), a monomer having no acid-labile group known in the field of resists can be used.
As the structural unit (s), a structural unit having a hydroxy group or a lactone ring and not having an acid labile group is preferred. A structural unit having a hydroxy group and no acid-labile group (hereinafter sometimes referred to as "structural unit (a2)") and/or a structure having a lactone ring and no acid-labile group When a resin having a unit (hereinafter sometimes referred to as "structural unit (a3)") is used in the resist composition of the present invention, the resolution of the resist pattern and adhesion to the substrate can be improved.

<Structural unit (a2)>
The hydroxy group possessed by the structural unit (a2) may be an alcoholic hydroxy group or a phenolic hydroxy group.
When producing a resist pattern from the resist composition of the present invention, when the exposure light source is a high energy beam such as a KrF excimer laser (248 nm), an electron beam or EUV (extreme ultraviolet light), it has a phenolic hydroxy group It is preferred to use the structural unit (a2). Moreover, when the exposure light source is an ArF excimer laser (193 nm) or the like, the structural unit (a2) having an alcoholic hydroxy group is preferable. As the structural unit (a2), one type may be contained alone, or two or more types may be contained.

［式（ａ２－Ａ）中、
Ｒ^a50は、水素原子、ハロゲン原子又はハロゲン原子を有していてもよい炭素数１～６のアルキル基を表す。
Ｒ^a51は、ハロゲン原子、ヒドロキシ基、炭素数１～６のアルキル基、炭素数１～６のアルコキシ基、炭素数２～４のアシル基、炭素数２～４のアシルオキシ基、アクリロイルオキシ基又はメタクリロイルオキシ基を表す。
Ａ^a50は、単結合又は^＊－Ｘ^a51－（Ａ^a52－Ｘ^a52）_na－を表し、＊は－Ｒ^a50が結合する炭素原子との結合手を表す。
Ａ^a52は、炭素数１～６のアルカンジイル基を表す。
Ｘ^a51及びＸ^a52は、それぞれ独立に、－Ｏ－、－ＣＯ－Ｏ－又は－Ｏ－ＣＯ－を表す。
ｎａは、０又は１を表す。
ｍｂは０～４のいずれかの整数を表す。ｍｂが２以上のいずれかの整数である場合、複数のＲ^a51は互いに同一であっても異なってもよい。］ The structural unit (a2) having a phenolic hydroxy group includes a structural unit represented by formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)").

[In the formula (a2-A),
R ^a50 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
R ^a51 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or represents a methacryloyloxy group.
A ^a50 represents a single bond or ^* -X ^a51 -(A ^a52 -X ^a52 ) _na -, and * represents a bond with the carbon atom to which -R ^a50 bonds.
A ^a52 represents an alkanediyl group having 1 to 6 carbon atoms.
X ^a51 and X ^a52 each independently represent -O-, -CO-O- or -O-CO-.
na represents 0 or 1;
mb represents an integer from 0 to 4; When mb is any integer of 2 or more, multiple R ^a51 may be the same or different. ]

Halogen atoms in R ^a50 include fluorine, chlorine and bromine atoms.
Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom for R ^a50 include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 1,1,1-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 1,1,1,2,2-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2,2, 3,3,4,4-octafluorobutyl group, butyl group, perfluoropentyl group, 1,1,1,2,2,3,3,4,4-nonafluoropentyl group, n-pentyl group, n- Hexyl groups and n-perfluorohexyl groups are included.
R ^a50 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

Examples of alkyl groups for R ^a51 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group and n-hexyl group.
The alkoxy group for R ^a51 includes methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy and tert-butoxy groups. An alkoxy group having 1 to 4 carbon atoms is preferred, a methoxy group or an ethoxy group is more preferred, and a methoxy group is even more preferred.
Acyl groups for R ^a51 include acetyl, propionyl and butyryl groups.
The acyloxy group for R ^a51 includes an acetyloxy group, a propionyloxy group and a butyryloxy group.
R ^a51 is preferably a methyl group.

^* -X ^a51 -(A ^a52 -X ^a52 ) _na - includes ^* -O-, ^* -CO-O-, ^* -O-CO-, ^* -CO-O-A ^a52 -CO-O-, ^* -O-CO-A ^a52 -O-, ^* -O-A ^a52 -CO-O-, ^* -CO-O-A ^a52 -O-CO-, ^* -O-CO-A ^a52 -O-CO -, are included. Among them, ^* -CO-O-, ^* -CO-OA ^a52 -CO-O- or ^{* -OA a52} -CO-O- is preferred.

The alkanediyl group includes methylene, ethylene, propane-1,3-diyl, propane-1,2-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane- 1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group and 2 -methylbutane-1,4-diyl group and the like.
A ^a52 is preferably a methylene group or an ethylene group.

A ^a50 is preferably a single bond, ^* -CO-O- or ^* -CO-O-A ^a52 -CO-O-, a single bond, ^* -CO-O- or ^* -CO-O-CH ₂ --CO--O-- is more preferred, and a single bond or ^* --CO--O-- is even more preferred.

mb is preferably 0, 1 or 2, more preferably 0 or 1, and particularly preferably 0.
The hydroxyl group is preferably bonded to the o-position or p-position of the benzene ring, more preferably bonded to the p-position.

Structural units (a2-A) include structural units represented by formulas (a2-2-1) to (a2-2-8). The structural unit (a2-A) includes a structural unit represented by formula (a2-2-1), a structural unit represented by formula (a2-2-1), and a structural unit represented by formula (a2-2-5). and a structural unit represented by formula (a2-2-6).

Examples of the monomer that induces the structural unit (a2-A) include monomers described in JP-A-2010-204634 and JP-A-2012-12577.

When the structural unit (a2-A) is contained in the resin (A), the content of the structural unit (a2-A) is preferably 5 to 80 mol%, more preferably It is 10 to 70 mol %, more preferably 15 to 65 mol %.

式（ａ２－１）中、
Ｌ^a3は、－Ｏ－又は^＊－Ｏ－（ＣＨ₂）_k2－ＣＯ－Ｏ－を表し、
ｋ２は１～７のいずれかの整数を表す。＊は－ＣＯ－との結合手を表す。
Ｒ^a14は、水素原子又はメチル基を表す。
Ｒ^a15及びＲ^a16は、それぞれ独立に、水素原子、メチル基又はヒドロキシ基を表す。
ｏ１は、０～１０のいずれかの整数を表す。 Examples of the structural unit (a2) having an alcoholic hydroxy group include structural units represented by formula (a2-1) (hereinafter sometimes referred to as "structural unit (a2-1)").

In formula (a2-1),
L ^a3 represents —O— or ^* —O—(CH ₂ ) _k2 —CO—O—;
k2 represents any integer from 1 to 7; * represents a bond with -CO-.
R ^a14 represents a hydrogen atom or a methyl group.
R ^a15 and R ^a16 each independently represent a hydrogen atom, a methyl group or a hydroxy group.
o1 represents any integer from 0 to 10;

In formula (a2-1), L ^a3 is preferably —O—, —O—(CH ₂ ) _f1 —CO—O— (f1 is an integer of 1 to 4). , more preferably -O-.
R ^a14 is preferably a methyl group.
R ^a15 is preferably a hydrogen atom.
R ^a16 is preferably a hydrogen atom or a hydroxy group.
o1 is preferably any integer from 0 to 3, more preferably 0 or 1.

Examples of structural units (a2-1) include structural units derived from monomers described in JP-A-2010-204646. Structural units represented by any one of formulas (a2-1-1) to (a2-1-6) are preferred.

When the resin (A) contains the structural unit (a2-1), its content is usually 1 to 45 mol%, preferably 1 to 40 mol%, based on the total structural units of the resin (A). Yes, more preferably 1 to 35 mol %, still more preferably 2 to 20 mol %.

<Structural unit (a3)>
The lactone ring of the structural unit (a3) may be a monocyclic ring such as a β-propiolactone ring, γ-butyrolactone ring, δ-valerolactone ring, or a condensed ring of a monocyclic lactone ring and another ring. It's okay. A γ-butyrolactone ring, an adamantanelactone ring, or a bridged ring containing a γ-butyrolactone ring structure is preferred.

Structural unit (a3) is preferably a structural unit represented by formula (a3-1), formula (a3-2), formula (a3-3) or formula (a3-4). One of these may be contained alone, or two or more may be contained.

［式（ａ３－１）、式（ａ３－２）、式（ａ３－３）及び式（ａ３－４）中、
Ｌ^ａ４、Ｌ^ａ５及びＬ^ａ６は、－Ｏ－又は^＊－Ｏ－（ＣＨ_２）_ｋ３－ＣＯ－Ｏ－（ｋ３は１～７のいずれかの整数を表す。）で表される基を表す。
Ｌ^ａ７は、－Ｏ－、^＊－Ｏ－Ｌ^ａ８－Ｏ－、^＊－Ｏ－Ｌ^ａ８－ＣＯ－Ｏ－、^＊－Ｏ－Ｌ^ａ８－ＣＯ－Ｏ－Ｌ^ａ９－ＣＯ－Ｏ－又は^＊－Ｏ－Ｌ^ａ８－Ｏ－ＣＯ－Ｌ^ａ９－Ｏ－を表す。
Ｌ^ａ８及びＬ^ａ９は、それぞれ独立に、炭素数１～６のアルカンジイル基を表す。
＊はカルボニル基との結合手を表す。
Ｒ^ａ１８、Ｒ^ａ１９及びＲ^ａ２０は、水素原子又はメチル基を表す。
Ｒ^ａ２４は、ハロゲン原子を有していてもよい炭素数１～６のアルキル基、水素原子又はハロゲン原子を表す。
Ｒ^ａ２１は炭素数１～４の脂肪族炭化水素基を表す。
Ｒ^ａ２２、Ｒ^ａ２３及びＲ^ａ２５は、カルボキシ基、シアノ基又は炭素数１～４の脂肪族炭化水素基を表す。
ｐ１は０～５のいずれかの整数を表す。
ｑ１は、０～３のいずれかの整数を表す。
ｒ１は、０～３のいずれかの整数を表す。
ｗ１は、０～８のいずれかの整数を表す。
ｐ１、ｑ１、ｒ１及び／又はｗ１が２以上のとき、複数のＲ^ａ２１、Ｒ^ａ２２、Ｒ^ａ２３及び／又はＲ^ａ２５は互いに同一であってもよく、異なってもよい。］

[In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4),
L ^a4 , L ^a5 and L ^a6 represent a group represented by —O— or ^* —O—(CH ₂ ) _k3 —CO—O— (k3 represents an integer of 1 to 7); .
L ^a7 is -O-, ^* -OL ^a8 -O-, ^* -OL ^a8 -CO-O-, ^* -OL ^a8 -CO- ^{OL a9} -CO-O- or ^* -OL ^a8 -O-CO-L ^a9 -O-.
L ^a8 and L ^a9 each independently represent an alkanediyl group having 1 to 6 carbon atoms.
* represents a bond with a carbonyl group.
R ^a18 , R ^a19 and R ^a20 each represent a hydrogen atom or a methyl group.
R ^a24 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
R ^a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
R ^a22 , R ^a23 and R ^a25 each represent a carboxy group, a cyano group or an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
p1 represents any integer from 0 to 5;
q1 represents an integer of 0 to 3;
r1 represents an integer of 0 to 3;
w1 represents any integer from 0 to 8;
When p1, q1, r1 and/or w1 are 2 or more, a plurality of R ^a21 , R ^a22 , R ^a23 and/or R ^a25 may be the same or different. ]

The aliphatic hydrocarbon groups represented by R ^a21 , R ^a22 , R ^a23 and R ^a25 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group and tert-butyl group. An alkyl group is mentioned.
The halogen atom for R ^a24 includes a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
Examples of the alkyl group for R ^a24 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group and n-hexyl group. , preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group.
The alkyl group having a halogen atom for R ^a24 includes a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluoro A hexyl group, a trichloromethyl group, a tribromomethyl group, a triiodomethyl group and the like are included.

The alkanediyl groups of L ^a8 and L ^a9 include methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5 -diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1, 4-diyl group, 2-methylbutane-1,4-diyl group and the like.

In formulas (a3-1) to (a3-3), L ^a4 to L ^a6 are each independently preferably —O— or *—O—(where k3 is an integer of 1 to 4) CH ₂ ) _k3 A group represented by -CO-O-, more preferably -O- and *-O-CH ₂ -CO-O-, more preferably an oxygen atom.
R ^a18 to R ^a21 are preferably methyl groups.
R ^a22 and R ^a23 are each independently preferably a carboxy group, a cyano group or a methyl group.
p1, q1, r1 and w1 are each independently preferably an integer from 0 to 2, more preferably 0 or 1.

（式中、Ｒ^ａ２４、Ｌ^ａ７は、上記と同じ意味を表す。） In formula (a3-4), R ^a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, still more preferably a hydrogen atom or a methyl group is.
R ^a25 is preferably a carboxy group, a cyano group or a methyl group.
L ^a7 is preferably -O- or ^* -OL ^a8 -CO-O-, more preferably -O-, -O-CH ₂ -CO-O- or -O-C ₂ H ₄ - It is CO—O—.
In particular, formula (a3-4) is preferably formula (a3-4)'.

(In the formula, R ^a24 and L ^a7 have the same meanings as above.)

Examples of the monomer leading to the structural unit (a3) include the monomers described in JP-A-2010-204646, the monomers described in JP-A-2000-122294, and the monomers described in JP-A-2012-41274. mentioned. As the structural unit (a3), formulas (a3-1-1) to (a3-1-4), formulas (a3-2-1) to (a3-2-4), formulas (a3-3- 1) to formulas (a3-3-4) and structural units represented by formulas (a3-4-1) to (a3-4-12) are preferred.

In the structural units represented by the above formulas (a3-4-1) to (a3-4-12), the compound in which the methyl group corresponding to R ^a24 is replaced with a hydrogen atom also includes the structural unit (a3-4 ) can be cited as a specific example.

When the resin (A) contains the structural unit (a3), the total content is usually 5 to 70 mol%, preferably 10 to 65 mol%, based on the total structural units of the resin (A). , more preferably 10 to 60 mol %.
Further, the content of structural unit (a3-1), structural unit (a3-2), structural unit (a3-3) and structural unit (a3-4) is is preferably 5 to 60 mol %, more preferably 5 to 50 mol %, even more preferably 10 to 50 mol %.

［式（ａ４－０）中、Ｒ⁵は、水素原子又はメチル基を表す。
Ｌ⁴は、単結合又は炭素数１～４の脂肪族飽和炭化水素基を表す。
Ｌ³は、炭素数１～８のペルフルオロアルカンジイル基又は炭素数３～１２のペルフルオロシクロアルカンジイル基を表す。
Ｒ⁶は、水素原子又はフッ素原子を表す。］ <Structural unit (a4)>
Structural unit (a4) is preferably a structural unit having a fluorine atom. Structural units (a4) include structural units represented by formula (a4-0).

[In formula (a4-0), R ⁵ represents a hydrogen atom or a methyl group.
L ⁴ represents a single bond or a C 1-4 saturated aliphatic hydrocarbon group.
L ³ represents a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms.
^R6 represents a hydrogen atom or a fluorine atom. ]

Examples of saturated aliphatic hydrocarbon groups for L ⁴ include linear alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, ethane-1,1- Branched alkanediyl groups such as diyl group, propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group and 2-methylpropane-1,2-diyl group groups.

The perfluoroalkanediyl group for L ³ includes a difluoromethylene group, a perfluoroethylene group, a perfluoropropane-1,1-diyl group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, and a perfluoropropane group. -2,2-diyl group, perfluorobutane-1,4-diyl group, perfluorobutane-2,2-diyl group, perfluorobutane-1,2-diyl group, perfluoropentane-1,5-diyl group, perfluoropentane -2,2-diyl group, perfluoropentane-3,3-diyl group, perfluorohexane-1,6-diyl group, perfluorohexane-2,2-diyl group, perfluorohexane-3,3-diyl group, perfluoroheptane -1,7-diyl group, perfluoroheptane-2,2-diyl group, perfluoroheptane-3,4-diyl group, perfluoroheptane-4,4-diyl group, perfluorooctane-1,8-diyl group, perfluorooctane -2,2-diyl group, perfluorooctane-3,3-diyl group, perfluorooctane-4,4-diyl group and the like.
The perfluorocycloalkanediyl group for L ³ includes a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, a perfluoroadamantanediyl group, and the like.

^L4 is preferably a single bond, a methylene group or an ethylene group, more preferably a single bond or a methylene group.
L ³ is preferably a C 1-6 perfluoroalkanediyl group, more preferably a C 1-3 perfluoroalkanediyl group.

Examples of the structural unit (a4-0) include structural units shown below and structural units in which a methyl group corresponding to R ⁵ in the following structural units is replaced with a hydrogen atom.

［式（ａ４－１）中、Ｒ^a41は、水素原子又はメチル基を表す。
Ｒ^a42は、置換基を有していてもよい炭素数１～２０の炭化水素基を表し、該炭化水素基に含まれる－ＣＨ₂－は、－Ｏ－又は－ＣＯ－に置き換わっていてもよい。
Ａ^a41は、置換基を有していてもよい炭素数１～６のアルカンジイル基又は式（ａ－ｇ１）で表される基を表す。ただし、Ａ^ａ４１及びＲ^ａ４２のうち少なくとも１つは、置換基としてハロゲン原子（好ましくはフッ素原子）を有する。

〔式（ａ－ｇ１）中、ｓは０又は１を表す。
Ａ^a42及びＡ^a44は、それぞれ独立に、置換基を有していてもよい炭素数１～５の２価の脂肪族炭化水素基を表す。
Ａ^a43は、単結合又は置換基を有していてもよい炭素数１～５の２価の脂肪族炭化水素基を表す。
Ｘ^a41及びＸ^a42は、それぞれ独立に、－Ｏ－、－ＣＯ－、－ＣＯ－Ｏ－又は－Ｏ－ＣＯ－を表す。
ただし、Ａ^a42、Ａ^a43、Ａ^a44、Ｘ^a41及びＸ^a42の炭素数の合計は７以下である。〕
＊は結合手であり、右側の＊が－Ｏ－ＣＯ－Ｒ^a42との結合手を表す。］ Structural units (a4) also include structural units represented by formula (a4-1).

[In formula (a4-1), R ^a41 represents a hydrogen atom or a methyl group.
R ^a42 represents an optionally substituted hydrocarbon group having 1 to 20 carbon atoms, and —CH ₂ — contained in the hydrocarbon group may be replaced with —O— or —CO— good.
A ^a41 represents an optionally substituted alkanediyl group having 1 to 6 carbon atoms or a group represented by formula (a-g1). However, at least one of A ^a41 and R ^a42 has a halogen atom (preferably a fluorine atom) as a substituent.

[In the formula (a-g1), s represents 0 or 1.
A ^a42 and A ^a44 each independently represent an optionally substituted divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms.
A ^a43 represents a single bond or an optionally substituted C 1-5 divalent aliphatic hydrocarbon group.
X ^a41 and X ^a42 each independently represent -O-, -CO-, -CO-O- or -O-CO-.
However, the total number of carbon atoms of A ^a42 , A ^a43 , A ^a44 , X ^a41 and X ^a42 is 7 or less. ]
* is a bond, and * on the right side represents a bond with —O—CO—R ^a42 . ]

The hydrocarbon group for R ^a42 includes chain and cyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these.
Chain and cyclic aliphatic hydrocarbon groups may have a carbon-carbon unsaturated bond, but chain and cyclic saturated aliphatic hydrocarbon groups are preferred. The aliphatic saturated hydrocarbon group includes a linear or branched alkyl group, a monocyclic or polycyclic alicyclic hydrocarbon group, and an aliphatic hydrocarbon group formed by combining an alkyl group and an alicyclic hydrocarbon group. group hydrocarbon groups and the like.

芳香族炭化水素基としては、フェニル基、ナフチル基、アントリル基、ビフェニリル基、フェナントリル基及びフルオレニル基等のアリール基；２－メチルフェニル基等のアルキル－アリール基；４－シクロヘキシルフェニル基等のシクロアルキル－アリール基等が挙げられる。 Chain type aliphatic hydrocarbon groups include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group and n-decyl. n-dodecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl and n-octadecyl groups. Cyclic aliphatic hydrocarbon groups include cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, methylcyclohexyl, dimethylcyclohexyl, and cycloalkyl groups such as methylnorbornyl; Naphthyl group, adamantyl group, norbornyl group, adamantylcyclohexyl group, and polycyclic alicyclic hydrocarbon groups such as the following groups (* represents a bond).

Aromatic hydrocarbon groups include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenylyl group, phenanthryl group and fluorenyl group; alkyl-aryl groups such as 2-methylphenyl group; Alkyl-aryl groups and the like are included.

［式（ａ－ｇ３）中、
Ｘ^a43は、酸素原子、カルボニル基、カルボニルオキシ基又はオキシカルボニル基を表す。
Ａ^a45は、少なくとも１つのハロゲン原子を有する炭素数１～１７の脂肪族炭化水素基を表す。
＊は結合手を表す。］ The hydrocarbon group for R ^a42 is preferably a chain or cyclic aliphatic hydrocarbon group or a group formed by combining these, and may have a carbon-carbon unsaturated bond. and cyclic aliphatic saturated hydrocarbon groups and groups formed by combining these groups are more preferred.
R ^a42 includes, as a substituent, a halogen atom or a group represented by formula (a-g3). A halogen atom includes a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, preferably a fluorine atom.

[In the formula (a-g3),
X ^a43 represents an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group.
A ^a45 represents a C 1-17 aliphatic hydrocarbon group having at least one halogen atom.
* represents a bond. ]

Examples of the aliphatic hydrocarbon group for A ^a45 include groups similar to those exemplified for R ^a42 .
R ^a42 is preferably an aliphatic hydrocarbon group which may have a halogen atom, more preferably an alkyl group having a halogen atom and/or an aliphatic hydrocarbon group having a group represented by formula (a-g3) preferable.
When R ^a42 is an aliphatic hydrocarbon group having a halogen atom, it is preferably an aliphatic hydrocarbon group having a fluorine atom, more preferably a perfluoroalkyl group or a perfluorocycloalkyl group, further preferably having a carbon number of It is a perfluoroalkyl group having 1 to 6 carbon atoms, particularly preferably a perfluoroalkyl group having 1 to 3 carbon atoms. Perfluoroalkyl groups include perfluoromethyl, perfluoroethyl, perfluoropropyl, perfluorobutyl, perfluoropentyl, perfluorohexyl, perfluoroheptyl and perfluorooctyl groups. A perfluorocyclohexyl group etc. are mentioned as a perfluorocycloalkyl group.
When R ^a42 is an aliphatic hydrocarbon group having a group represented by formula (a-g3), including the number of carbon atoms contained in the group represented by formula (a-g3), the aliphatic hydrocarbon The total number of carbon atoms in the group is preferably 15 or less, more preferably 12 or less. When it has a group represented by formula (a-g3) as a substituent, the number thereof is preferably one.

［式（ａ－ｇ２）中、
Ａ^a46は、ハロゲン原子を有していてもよい炭素数１～１７の脂肪族炭化水素基を表す。
Ｘ^a44は、カルボニルオキシ基又はオキシカルボニル基を表す。
Ａ^a47は、ハロゲン原子を有していてもよい炭素数１～１７の脂肪族炭化水素基を表す。
ただし、Ａ^a46、Ａ^a47及びＸ^a44の炭素数の合計は１８以下であり、Ａ^a46及びＡ^a47のうち、少なくとも一方は、少なくとも１つのハロゲン原子を有する。
＊はカルボニル基との結合手を表す。］ The aliphatic hydrocarbon having a group represented by formula (a-g3) is more preferably a group represented by formula (a-g2).

[In the formula (a-g2),
A ^a46 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom.
X ^a44 represents a carbonyloxy group or an oxycarbonyl group.
A ^a47 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom.
However, the total number of carbon atoms of A ^a46 , A ^a47 and X ^a44 is 18 or less, and at least one of A ^a46 and A ^a47 has at least one halogen atom.
* represents a bond with a carbonyl group. ]

The number of carbon atoms in the aliphatic hydrocarbon group of A ^a46 is preferably 1-6, more preferably 1-3.
The number of carbon atoms in the aliphatic hydrocarbon group of A ^a47 is preferably 4 to 15, more preferably 5 to 12, and A ^a47 is more preferably a cyclohexyl group or an adamantyl group.

A more preferred structure of the partial structure represented by *-A ^a46 -X ^a44 -A ^a47 (* represents a bond with a carbonyl group) is the following structure.

The alkanediyl group of A ^a41 includes methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group and hexane-1,6-diyl group. straight-chain alkanediyl groups such as; A branched alkanediyl group such as a 2-methylbutane-1,4-diyl group can be mentioned.
Examples of substituents on the alkanediyl group of A ^a41 include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms.
A ^a41 is preferably an alkanediyl group having 1 to 4 carbon atoms, more preferably an alkanediyl group having 2 to 4 carbon atoms, and still more preferably an ethylene group.

Aliphatic hydrocarbon groups of A ^a42 , A ^a43 and A ^a44 in the group represented by formula (a-g1) may have a carbon-carbon unsaturated bond, but chain and cyclic aliphatic Group saturated hydrocarbon groups as well as groups formed by combinations thereof are preferred. The saturated aliphatic hydrocarbon group includes a linear or branched alkyl group, a monocyclic or polycyclic alicyclic hydrocarbon group, and a combination of an alkyl group and an alicyclic hydrocarbon group. An aliphatic hydrocarbon group etc. are mentioned. Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group and the like.
Substituents of the aliphatic hydrocarbon groups of A ^a42 , A ^a43 and A ^a44 include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms.
s is preferably zero.

Examples of the group represented by the formula (a-g1) in which X ^a42 represents an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group include the following groups. In the following examples, * and ** each represent a bond, and ** represents a bond with --O--CO--R ^a42 .

Examples of the structural unit represented by formula (a4-1) include structural units shown below and structural units in which a methyl group corresponding to R ^a41 in the structural units below is replaced with a hydrogen atom.

［式（ａ４－４）中、Ｒ^f21は、水素原子又はメチル基を表す。
Ａ^f21は、－（ＣＨ₂）_j1－、－（ＣＨ₂）_j2－Ｏ－（ＣＨ₂）_j3－又は－（ＣＨ₂）_j4－ＣＯ－Ｏ－（ＣＨ₂）_j5－を表す。
ｊ１～ｊ５は、それぞれ独立に、１～６のいずれかの整数を表す。
Ｒ^f22は、フッ素原子を有する炭素数１～１０の炭化水素基を表す。］ Structural units (a4) also include structural units represented by formula (a4-4).

[In formula (a4-4), R ^f21 represents a hydrogen atom or a methyl group.
A ^f21 represents -(CH ₂ ) _j1 -, -(CH ₂ ) _j2 -O-(CH ₂ ) _j3 - or -(CH ₂ ) _j4 -CO-O-(CH ₂ ) _j5 -.
j1 to j5 each independently represent an integer of 1 to 6;
R ^f22 represents a hydrocarbon group having 1 to 10 carbon atoms and having a fluorine atom. ]

Examples of the hydrocarbon group having a fluorine atom for R ^f22 include an alkyl group having a fluorine atom and an alicyclic hydrocarbon group having a fluorine atom.
Alkyl groups having a fluorine atom include difluoromethyl group, trifluoromethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, perfluoroethyl group, 1 , 1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1-(trifluoromethyl)-1,2,2,2- tetrafluoroethyl group, 1-(trifluoromethyl)-2,2,2-trifluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3 ,3-hexafluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, perfluorobutyl group, 1,1-bis(trifluoro)methyl-2,2,2- trifluoroethyl group, 2-(perfluoropropyl)ethyl group, 1,1,2,2,3,3,4,4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3 , 4,4,5,5-decafluoropentyl group, 1,1-bis(trifluoromethyl)-2,2,3,3,3-pentafluoropropyl group, 2-(perfluorobutyl)ethyl group, 1 , 1,2,2,3,3,4,4,5,5-decafluorohexyl group, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluoro Fluorinated alkyl groups such as a hexyl group, a perfluoropentylmethyl group and a perfluorohexyl group can be mentioned.
The alicyclic hydrocarbon group having a fluorine atom includes fluorinated cycloalkyl groups such as a perfluorocyclohexyl group and a perfluoroadamantyl group.
R ^f22 is preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom or an alicyclic hydrocarbon group having 1 to 10 carbon atoms having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom. An alkyl group having 1 to 6 carbon atoms and having a fluorine atom is more preferred.

In formula (a4-4), A ^f21 is preferably --(CH ₂ ) _j1 --, more preferably an ethylene group or a methylene group, and still more preferably a methylene group.

Examples of the structural unit represented by the formula (a4-4) include the following structural units and structural units in which the methyl group corresponding to R ^f21 is replaced with a hydrogen atom in the structural units represented by the following formula. be done.

When the resin (A) has the structural unit (a4), the content thereof is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, based on the total structural units of the resin (A), and 3 ~10 mol% is more preferred.

［式（ａ５－１）中、
Ｒ⁵¹は、水素原子又はメチル基を表す。
Ｒ⁵²は、炭素数３～１８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水素原子は炭素数１～８の脂肪族炭化水素基で置換されていてもよい。但し、Ｌ^5５との結合位置にある炭素原子に結合する水素原子は、炭素数１～８の脂肪族炭化水素基で置換されない。
Ｌ^5５は、単結合又は炭素数１～１８の２価の飽和炭化水素基を表し、該飽和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に置き換わっていてもよい。］ <Structural unit (a5)>
Examples of non-leaving hydrocarbon groups possessed by the structural unit (a5) include groups having linear, branched or cyclic hydrocarbon groups. Among them, the structural unit (a5) preferably contains a group having an alicyclic hydrocarbon group.
Structural units (a5) include structural units represented by formula (a5-1).

[In formula (a5-1),
^R51 represents a hydrogen atom or a methyl group.
R ⁵² represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and a hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms. . However, the hydrogen atom bonded to the carbon atom at the bonding position with L ⁵⁵ is not substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms.
L ⁵⁵ represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and the methylene group contained in the saturated hydrocarbon group may be replaced with an oxygen atom or a carbonyl group. ]

The alicyclic hydrocarbon group for R ⁵² may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl groups. Examples of polycyclic alicyclic hydrocarbon groups include adamantyl groups and norbornyl groups.
C1-C8 aliphatic hydrocarbon groups include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, Examples include alkyl groups such as octyl and 2-ethylhexyl.
A 3-methyladamantyl group etc. are mentioned as an alicyclic hydrocarbon group having a substituent.
R ⁵² is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, more preferably an adamantyl group, a norbornyl group or a cyclohexyl group.

The bivalent saturated hydrocarbon group for L ⁵⁵ includes a bivalent saturated aliphatic hydrocarbon group and a saturated bivalent alicyclic hydrocarbon group, preferably a saturated aliphatic hydrocarbon group. .
Examples of divalent aliphatic saturated hydrocarbon groups include alkanediyl groups such as methylene, ethylene, propanediyl, butanediyl and pentanediyl groups.
The bivalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. The monocyclic alicyclic saturated hydrocarbon group includes cycloalkanediyl groups such as cyclopentanediyl group and cyclohexanediyl group. The polycyclic bivalent alicyclic saturated hydrocarbon group includes an adamantanediyl group and a norbornanediyl group.

式（Ｌ１－１）中、
Ｘ^x1は、カルボニルオキシ基又はオキシカルボニル基を表す。
Ｌ^x1は、炭素数１～１６の２価の脂肪族飽和炭化水素基を表す。
Ｌ^x2は、単結合又は炭素数１～１５の２価の脂肪族飽和炭化水素基を表す。
ただし、Ｌ^x1及びＬ^x2の合計炭素数は、１６以下である。
式（Ｌ１－２）中、
Ｌ^x3は、炭素数１～１７の２価の脂肪族飽和炭化水素基を表す。
Ｌ^x4は、単結合又は炭素数１～１６の２価の脂肪族飽和炭化水素基を表す。
ただし、Ｌ^x3及びＬ^x4の合計炭素数は、１７以下である。
式（Ｌ１－３）中、
Ｌ^x5は、炭素数１～１５の２価の脂肪族飽和炭化水素基を表す。
Ｌ^x6及びＬ^x7は、それぞれ独立に、単結合又は炭素数１～１４の２価の脂肪族飽和炭化水素基を表す。
ただし、Ｌ^x5、Ｌ^x6及びＬ^x7の合計炭素数は、１５以下である。
式（Ｌ１－４）中、
Ｌ^x8及びＬ^x9は、単結合又は炭素数１～１２の２価の脂肪族飽和炭化水素基を表す。
Ｗ^x1は、炭素数３～１５の２価の脂環式飽和炭化水素基を表す。
ただし、Ｌ^x8、Ｌ^x9及びＷ^x1の合計炭素数は、１５以下である。 Examples of the saturated hydrocarbon group in which the methylene group is replaced with an oxygen atom or a carbonyl group include groups represented by formulas (L1-1) to (L1-4). In the following formula, * represents a bond with an oxygen atom.

In formula (L1-1),
X ^x1 represents a carbonyloxy group or an oxycarbonyl group.
L ^x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms.
L ^x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms.
However, the total carbon number of L ^x1 and L ^x2 is 16 or less.
In formula (L1-2),
L ^x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms.
L ^x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms.
However, the total carbon number of L ^x3 and L ^x4 is 17 or less.
In formula (L1-3),
L ^x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^x6 and L ^x7 each independently represent a single bond or a divalent saturated aliphatic hydrocarbon group having 1 to 14 carbon atoms.
However, the total carbon number of L ^x5 , L ^x6 and L ^x7 is 15 or less.
In formula (L1-4),
L ^x8 and L ^x9 each represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms.
W ^x1 represents a divalent saturated alicyclic hydrocarbon group having 3 to 15 carbon atoms.
However, the total carbon number of L ^x8 , L ^x9 and W ^x1 is 15 or less.

L ^x1 is preferably a C 1-8 divalent aliphatic saturated hydrocarbon group, more preferably a methylene group or an ethylene group.
L ^x2 is preferably a single bond or a C 1-8 divalent aliphatic saturated hydrocarbon group, more preferably a single bond.
L ^x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^x5 is preferably a C 1-8 divalent aliphatic saturated hydrocarbon group, more preferably a methylene group or an ethylene group.
L ^x6 is preferably a single bond or a C 1-8 divalent aliphatic saturated hydrocarbon group, more preferably a methylene group or an ethylene group.
L ^x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^x8 is preferably a single bond or a divalent saturated aliphatic hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group.
L ^x9 is preferably a single bond or a divalent saturated aliphatic hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group.
W ^x1 is preferably a divalent saturated alicyclic hydrocarbon group having 3 to 10 carbon atoms, more preferably a cyclohexanediyl group or an adamantanediyl group.

Examples of the group represented by formula (L1-1) include the divalent groups shown below.

Examples of the group represented by formula (L1-2) include the divalent groups shown below.

Examples of the group represented by formula (L1-3) include the divalent groups shown below.

Examples of the group represented by formula (L1-4) include the divalent groups shown below.

L ⁵⁵ is preferably a single bond or a group represented by formula (L1-1).

樹脂（Ａ）が、構造単位（ａ５）を有する場合、その含有率は、樹脂（Ａ）の全構造単位に対して、１～３０モル％が好ましく、２～２０モル％がより好ましく、３～１５モル％がさらに好ましい。 The structural unit (a5-1) includes the following structural units and structural units in which the methyl group corresponding to R ⁵¹ in the following structural units is replaced with a hydrogen atom.

When the resin (A) has the structural unit (a5), the content thereof is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, based on the total structural units of the resin (A), and 3 ~15 mol% is more preferred.

<Structural unit (II)>
The resin (A) may further contain a structural unit that is decomposed by exposure to generate an acid (hereinafter sometimes referred to as "structural unit (II)"). Examples include a structural unit containing a group represented by formula (III-1) or formula (III-2) described in JP-A-2016-79235, and a sulfonate group or a carboxylate group and an organic A structural unit having a cation or a structural unit having a sulfonio group and an organic anion in a side chain is preferable.

［式（ＩＩ－２－Ａ’）中、
Ｘ^ＩＩＩ３は、炭素数１～１８の２価の飽和炭化水素基を表し、該飽和炭化水素基に含まれる－ＣＨ_２－は、－Ｏ－、－Ｓ－又は－ＣＯ－に置き換わっていてもよく、該飽和炭化水素基に含まれる水素原子は、ハロゲン原子、ハロゲン原子を有していてもよい炭素数１～６のアルキル基又はヒドロキシ基で置き換わっていてもよい。
Ａ^ｘ１は、炭素数１～８のアルカンジイル基を表し、該アルカンジイル基に含まれる水素原子は、フッ素原子又は炭素数１～６のペルフルオロアルキル基で置換されていてもよい。
ＲＡ^－は、スルホナート基又はカルボキシレート基を表す。
Ｒ^ＩＩＩ３は、水素原子、ハロゲン原子又はハロゲン原子を有していてもよい炭素数１～６のアルキル基を表す。
Ｚ^ａ＋は、有機カチオンを表す。］ A structural unit having a sulfonate group or a carboxylate group in a side chain is preferably a structural unit represented by formula (II-2-A').

[In the formula (II-2-A '),
X ^III3 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and —CH ₂ — contained in the saturated hydrocarbon group may be replaced with —O—, —S— or —CO— A hydrogen atom contained in the saturated hydrocarbon group may be replaced with a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, or a hydroxy group.
A ^x1 represents an alkanediyl group having 1 to 8 carbon atoms, and a hydrogen atom contained in the alkanediyl group may be substituted with a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms.
RA- represents a sulfonate group ^or a carboxylate group.
R ^III3 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
Z ^a+ represents an organic cation. ]

Halogen atoms represented by R ^III3 include fluorine, chlorine, bromine and iodine atoms.
The alkyl group having 1 to 6 carbon atoms and optionally having a halogen atom represented by R ^III3 includes an alkyl group having 1 to 6 carbon atoms and optionally having a halogen atom represented by R ^a8 . The same can be mentioned.
The alkanediyl group having 1 to 8 carbon atoms represented by A ^x1 includes methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group and pentane-1,5-diyl group. , hexane-1,6-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2, 4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, etc. mentioned.

Examples of the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by X ^III3 include a linear or branched alkanediyl group and a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group. and may be a combination of these.
Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1 ,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group , dodecane-1,12-diyl group and other linear alkanediyl groups; butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group , pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group and other branched alkanediyl groups; cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1 ,4-diyl group, cycloalkanediyl group such as cyclooctane-1,5-diyl group; norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane Divalent polycyclic alicyclic saturated hydrocarbon groups such as -2,6-diyl group and the like can be mentioned.
Groups in which an alkanediyl group and an alicyclic saturated hydrocarbon group are combined include, for example, cycloalkyl-alkanediyl groups such as a cyclohexylmethylene group, an adamantylmethylene group and a norbornylethylene group.

Examples of saturated hydrocarbon groups in which —CH ₂ — is replaced with —O—, —S— or —CO— include divalent groups represented by formulas (X1) to (X53). mentioned. However, each —CH ₂ — contained in the saturated hydrocarbon group has 17 or less carbon atoms before being replaced with —O—, —S— or —CO—. In the following formula, * represents a bond with A ^x1 .

X ³ represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms.
X ⁴ represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms.
X ⁵ represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.
X ⁶ represents an alkyl group having 1 to 14 carbon atoms.
X ⁷ represents a trivalent saturated hydrocarbon group having 1 to 14 carbon atoms.
X ⁸ represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.

Organic cations represented by Z ^a+ include organic onium cations such as organic sulfonium cations, organic iodonium cations, organic ammonium cations, organic benzothiazolium cations and organic phosphonium cations, and organic sulfonium cations and organic iodonium cations. are preferred, and arylsulfonium cations are more preferred.

［式（ｂ２－１）～式（ｂ２－４）において、
Ｒ^ｂ４～Ｒ^ｂ６は、それぞれ独立に、炭素数１～３０のアルキル基、炭素数３～３６の脂環式炭化水素基又は炭素数６～３６の芳香族炭化水素基を表し、該アルキル基に含まれる水素原子は、ヒドロキシ基、炭素数１～１２のアルコキシ基、炭素数３～１２の脂環式炭化水素基又は炭素数６～１８の芳香族炭化水素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水素原子は、ハロゲン原子、炭素数１～１８のアルキル基、炭素数２～４のアシル基又はグリシジルオキシ基で置換されていてもよく、該芳香族炭化水素基に含まれる水素原子は、ハロゲン原子、ヒドロキシ基又は炭素数１～１２のアルコキシ基で置換されていてもよい。
Ｒ^ｂ４とＲ^ｂ５とは、それらが結合する硫黄原子とともに環を形成してもよく、該環に含まれる－ＣＨ_２－は、－Ｏ－、－ＳＯ－又は－ＣＯ－に置き換わってもよい。
Ｒ^ｂ７及びＲ^ｂ８は、それぞれ独立に、ヒドロキシ基、炭素数１～１２の脂肪族炭化水素基又は炭素数１～１２のアルコキシ基を表す。
ｍ２及びｎ２は、それぞれ独立に、０～５のいずれかの整数を表す。
ｍ２が２以上のとき、複数のＲ^ｂ７は同一であっても異なってもよく、ｎ２が２以上のとき、複数のＲ^ｂ８は同一であっても異なってもよい。
Ｒ^ｂ９及びＲ^ｂ１０は、それぞれ独立に、炭素数１～３６のアルキル基又は炭素数３～３６の脂環式炭化水素基を表す。
Ｒ^ｂ９とＲ^ｂ１０とは、それらが結合する硫黄原子とともに環を形成してもよく、該環に含まれる－ＣＨ_２－は、－Ｏ－、－ＳＯ－又は－ＣＯ－に置き換わってもよい。
Ｒ^ｂ１１は、水素原子、炭素数１～３６のアルキル基、炭素数３～３６の脂環式炭化水素基又は炭素数６～１８の芳香族炭化水素基を表す。
Ｒ^ｂ１２は、炭素数１～１２のアルキル基、炭素数３～１８の脂環式炭化水素基又は炭素数６～１８の芳香族炭化水素基を表し、該アルキル基に含まれる水素原子は、炭素数６～１８の芳香族炭化水素基で置換されていてもよく、該芳香族炭化水素基に含まれる水素原子は、炭素数１～１２のアルコキシ基又は炭素数１～１２のアルキルカルボニルオキシ基で置換されていてもよい。
Ｒ^ｂ１１とＲ^ｂ１２とは、一緒になってそれらが結合する－ＣＨ－ＣＯ－を含む環を形成していてもよく、該環に含まれる－ＣＨ_２－は、－Ｏ－、－ＳＯ－又は－ＣＯ－に置き換わってもよい。
Ｒ^ｂ１３～Ｒ^ｂ１８は、それぞれ独立に、ヒドロキシ基、炭素数１～１２の脂肪族炭化水素基又は炭素数１～１２のアルコキシ基を表す。
Ｌ^ｂ３１は、－Ｓ－又は－Ｏ－を表す。
ｏ２、ｐ２、ｓ２、及びｔ２は、それぞれ独立に、０～５のいずれかの整数を表す。
ｑ２及びｒ２は、それぞれ独立に、０～４のいずれかの整数を表す。
ｕ２は、０又は１を表す。
ｏ２が２以上のとき、複数のＲ^ｂ１３は同一であっても異なってもよく、ｐ２が２以上のとき、複数のＲ^ｂ１４は同一であっても異なってもよく、ｑ２が２以上のとき、複数のＲ^ｂ１５は同一であっても異なってもよく、ｒ２が２以上のとき、複数のＲ^ｂ１６は同一であっても異なってもよく、ｓ２が２以上のとき、複数のＲ^ｂ１７は同一であっても異なってもよく、ｔ２が２以上のとき、複数のＲ^ｂ１８は同一であっても異なってもよい。］ Z ^a+ is preferably a cation represented by any one of formulas (b2-1) to (b2-4) [hereinafter sometimes referred to as "cation (b2-1)" etc. depending on the formula number. ].

[In formulas (b2-1) to (b2-4),
R ^b4 to R ^b6 each independently represent an alkyl group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms or an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the alkyl group The hydrogen atoms contained in may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. , the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an alkyl group having 1 to 18 carbon atoms, an acyl group having 2 to 4 carbon atoms or a glycidyloxy group, and the aromatic A hydrogen atom contained in the hydrocarbon group may be substituted with a halogen atom, a hydroxy group or an alkoxy group having 1 to 12 carbon atoms.
R ^b4 and R ^b5 may form a ring together with the sulfur atom to which they are bonded, and -CH ₂ - contained in the ring may be replaced with -O-, -SO- or -CO- .
R ^b7 and R ^b8 each independently represent a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms.
m2 and n2 each independently represent an integer of 0 to 5;
When m2 is 2 or more, the plurality of R ^b7 may be the same or different, and when n2 is 2 or more, the plurality of R ^b8 may be the same or different.
R ^b9 and R ^b10 each independently represent an alkyl group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms.
R ^b9 and R ^b10 may form a ring together with the sulfur atom to which they are bonded, and —CH ₂ — contained in the ring may be replaced with —O—, —SO— or —CO— .
R ^b11 represents a hydrogen atom, an alkyl group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms.
R ^b12 represents an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the alkyl group is It may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the aromatic hydrocarbon group is an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. may be substituted with a group.
R ^b11 and R ^b12 may together form a ring containing —CH—CO— to which they are bonded, and —CH ₂ — contained in the ring is —O—, —SO— Alternatively, it may be replaced with -CO-.
R ^b13 to R ^b18 each independently represent a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms.
L ^b31 represents -S- or -O-.
o2, p2, s2, and t2 each independently represent an integer of 0 to 5;
q2 and r2 each independently represent an integer of 0 to 4;
u2 represents 0 or 1;
When o2 is 2 or more, the plurality of R ^b13 may be the same or different, when p2 is 2 or more, the plurality of R ^b14 may be the same or different, and when q2 is 2 or more , the plurality of R ^b15 may be the same or different, when r2 is 2 or more, the plurality of R ^b16 may be the same or different, and when s2 is 2 or more, the plurality of R ^b17 may be They may be the same or different, and when t2 is 2 or more, a plurality of R ^b18 may be the same or different. ]

中でも、Ｒ^ｂ９～Ｒ^ｂ１２のアルキル基の炭素数は、好ましくは３～１８であり、より好ましくは４～１２である。 Examples of alkyl groups include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. be done. Among them, the alkyl groups of R ^b9 to R ^b12 preferably have 1 to 12 carbon atoms.
The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples of monocyclic alicyclic hydrocarbon groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cycloalkyl groups such as a group, a cyclooctyl group, and a cyclodecyl group. The polycyclic alicyclic hydrocarbon group includes decahydronaphthyl group, adamantyl group, norbornyl group, and the following groups.

Among them, the number of carbon atoms in the alkyl groups of R ^b9 to R ^b12 is preferably 3-18, more preferably 4-12.

Examples of alicyclic hydrocarbon groups in which hydrogen atoms are substituted with alkyl groups include methylcyclohexyl group, dimethylcyclohexyl group, 2-alkyladamantan-2-yl group, methylnorbornyl group and isobornyl group. mentioned. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with any group, the total number of carbon atoms of the alicyclic hydrocarbon group and the alkyl group is preferably 20 or less.
The aliphatic hydrocarbon groups of R ^b7 and R ^b8 , and R ^b13 to R ^b18 include the same alkyl groups, alicyclic hydrocarbon groups, and combinations thereof as described above.

Aromatic hydrocarbon groups include aryl groups such as phenyl, biphenylyl, naphthyl, and phenanthryl groups; tolyl, xylyl, cumenyl, mesityl, p-ethylphenyl, p-tert-butylphenyl, Alkyl-aryl groups such as 2,6-diethylphenyl group and 2-methyl-6-ethylphenyl group; and cycloalkyl-aryl groups such as p-cyclohexylphenyl group and p-adamantylphenyl group.
When the aromatic hydrocarbon group contains an alkyl group or an alicyclic hydrocarbon group, an alkyl group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferable.
Aromatic hydrocarbon groups in which a hydrogen atom is substituted with an alkoxy group include a p-methoxyphenyl group and the like.
Alkyl groups in which hydrogen atoms are substituted with aromatic hydrocarbon groups include aralkyl groups such as benzyl, phenethyl, phenylpropyl, trityl, naphthylmethyl, and naphthylethyl groups.

Alkoxy groups include methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, decyloxy and dodecyloxy groups.
Acyl groups include acetyl, propionyl and butyryl groups.
Halogen atoms include fluorine, chlorine, bromine and iodine atoms.
The alkylcarbonyloxy group includes a methylcarbonyloxy group, an ethylcarbonyloxy group, an n-propylcarbonyloxy group, an isopropylcarbonyloxy group, an n-butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, pentylcarbonyloxy group, hexylcarbonyloxy group, octylcarbonyloxy group, 2-ethylhexylcarbonyloxy group and the like.

The ring that R ^b4 and R ^b5 may form together with the sulfur atom to which they are bonded is a monocyclic, polycyclic, aromatic, non-aromatic, saturated or unsaturated ring. There may be. The ring includes a ring having 3 to 18 carbon atoms, preferably a ring having 4 to 18 carbon atoms. Further, the ring containing a sulfur atom includes a 3- to 12-membered ring, preferably a 3- to 7-membered ring, and specific examples include the following rings.

The ring formed by R ^b9 and R ^b10 together with the sulfur atom to which they are bonded may be a monocyclic, polycyclic, aromatic, non-aromatic, saturated or unsaturated ring. good. The ring includes a 3- to 12-membered ring, preferably a 3- to 7-membered ring, such as thiolan-1-ium ring (tetrahydrothiophenium ring), thian-1-ium ring, 1,4-oxathian-4-ium ring and the like.
The ring formed by R ^b11 and R ^b12 together may be a monocyclic, polycyclic, aromatic, non-aromatic, saturated or unsaturated ring. The ring includes a 3- to 12-membered ring, preferably a 3- to 7-membered ring, such as an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, an oxoadamantane ring, and the like. be done.

Among the cations (b2-1) to (b2-4), the cation (b2-1) is preferred.

Examples of the cation (b2-1) include the following cations.

Examples of the cation (b2-2) include the following cations.

Examples of the cation (b2-3) include the following cations.

Examples of the cation (b2-4) include the following cations.

［式（ＩＩ－２－Ａ）中、Ｒ^ＩＩＩ３、Ｘ^ＩＩＩ３及びＺ^ａ＋は、上記と同じ意味を表す。
Ｚは、０～６のいずれかの整数を表す。
Ｒ^ＩＩＩ２及びＲ^ＩＩＩ４は、それぞれ独立して、水素原子、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し、ｚが２以上のとき、複数のＲ^ＩＩＩ２及びＲ^ＩＩＩ４は互いに同一であってもよいし、異なっていてもよい。
Ｑ^ａ及びＱ^ｂは、それぞれ独立して、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。］ The structural unit represented by formula (II-2-A') is preferably a structural unit represented by formula (II-2-A).

[In formula (II-2-A), R ^III3 , X ^III3 and Z ^a+ have the same meanings as above.
Z represents any integer from 0 to 6.
R ^III2 and R ^III4 each independently represent a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms, and when z is 2 or more, a plurality of R ^III2 and R ^III4 are the same may be different.
Q ^a and Q ^b each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group. ]

Examples of the perfluoroalkyl group having 1 to 6 carbon atoms represented by R ^III2 , R ^III4 , Q ^a and Q ^b include the same perfluoroalkyl groups having 1 to 6 carbon atoms represented by Q ¹ described later. .

［式（ＩＩ－２－Ａ－１）中、
Ｒ^ＩＩＩ２、Ｒ^ＩＩＩ３、Ｒ^ＩＩＩ４、Ｑ^a、Ｑ^b、ｚ及びＺ^a＋は、上記と同じ意味を表す。
Ｒ^ＩＩＩ５は、炭素数１～１２の飽和炭化水素基を表す。
Ｘ²は、炭素数１～１１の２価の飽和炭化水素基を表し、該飽和炭化水素基に含まれる－ＣＨ_２－は、－Ｏ－、－Ｓ－又は－ＣＯ－に置き換わっていてもよく、該飽和炭化水素基に含まれる水素原子は、ハロゲン原子又はヒドロキシ基で置換されていてもよい。］ The structural unit represented by formula (II-2-A) is preferably a structural unit represented by formula (II-2-A-1).

[In formula (II-2-A-1),
R ^III2 , R ^III3 , R ^III4 , Q ^a , Q ^b , z and Z ^a+ have the same meanings as above.
R ^III5 represents a saturated hydrocarbon group having 1 to 12 carbon atoms.
X ² represents a divalent saturated hydrocarbon group having 1 to 11 carbon atoms, and —CH ₂ — contained in the saturated hydrocarbon group may be replaced with —O—, —S— or —CO—. A hydrogen atom contained in the saturated hydrocarbon group may be substituted with a halogen atom or a hydroxy group. ]

Examples of saturated hydrocarbon groups having 1 to 12 carbon atoms represented by R ^III5 include methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, Linear or branched alkyl groups such as heptyl group, octyl group, nonyl group, decyl group, undecyl group and dodecyl group can be mentioned.
The divalent saturated hydrocarbon group having 1 to 11 carbon atoms represented by X ² includes those having up to 11 carbon atoms among the divalent saturated hydrocarbon groups represented by X ^III3 .

［式（ＩＩ－２－Ａ－２）中、Ｒ^ＩＩＩ３、Ｒ^ＩＩＩ５及びＺ^a＋は、上記と同じ意味を表す。
ｍ及びｎは、互いに独立に、１又は２を表す。］ As the structural unit represented by formula (II-2-A-1), a structural unit represented by formula (II-2-A-2) is more preferable.

[In formula (II-2-A-2), R ^III3 , R ^III5 and Z ^a+ have the same meanings as above.
m and n each independently represent 1 or 2; ]

Examples of structural units represented by formula (II-2-A-1) include the following structural units and structural units described in WO2012/050015. Z ^a+ represents an organic cation.

［式（ＩＩ－１－１）中、
Ａ^ＩＩ１は、単結合又は２価の連結基を表す。
Ｒ^ＩＩ１は、炭素数６～１８の２価の芳香族炭化水素基を表す。
Ｒ^ＩＩ２及びＲ^ＩＩ３は、それぞれ独立して、炭素数１～３０のアルキル基、炭素数３～３６の脂環式炭化水素基又は炭素数６～３６の芳香族炭化水素基を表し、該アルキル基に含まれる水素原子は、ヒドロキシ基、炭素数１～１２のアルコキシ基、炭素数３～１２の脂環式炭化水素基又は炭素数６～１８の芳香族炭化水素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水素原子は、ハロゲン原子、炭素数１～１８のアルキル基、炭素数２～４のアシル基又はグリシジルオキシ基で置換されていてもよく、該芳香族炭化水素基に含まれる水素原子は、ハロゲン原子、ヒドロキシ基又は炭素数１～１２のアルコキシ基で置換されていてもよい。また、Ｒ^ＩＩ２とＲ^ＩＩ３とは、それらが結合する硫黄原子とともに環を形成してもよく、該環に含まれる－ＣＨ_２－は、－Ｏ－、－ＳＯ－又は－ＣＯ－に置き換わってもよい。
Ｒ^II4は、水素原子、ハロゲン原子又はハロゲン原子を有していてもよい炭素数１～６のアルキル基を表す。
Ａ^－は、有機アニオンを表す。］ A structural unit having a sulfonio group and an organic anion in a side chain is preferably a structural unit represented by formula (II-1-1).

[In the formula (II-1-1),
^AII1 represents a single bond or a divalent linking group.
R ^II1 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms.
R ^II2 and R ^II3 each independently represent an alkyl group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms or an aromatic hydrocarbon group having 6 to 36 carbon atoms; A hydrogen atom contained in the group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms. A hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an alkyl group having 1 to 18 carbon atoms, an acyl group having 2 to 4 carbon atoms or a glycidyloxy group, and the aromatic A hydrogen atom contained in the group hydrocarbon group may be substituted with a halogen atom, a hydroxy group or an alkoxy group having 1 to 12 carbon atoms. In addition, R ^II2 and R ^II3 may form a ring together with the sulfur atom to which they are bonded, and —CH ₂ — contained in the ring is replaced with —O—, —SO— or —CO— good too.
R ^II4 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
A ⁻ represents an organic anion. ]

The divalent linking group represented by A ^II1 includes, for example, a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and —CH ₂ — contained in the divalent saturated hydrocarbon group is -O-, -S- or -CO- may be substituted. Specific examples thereof include the same divalent saturated hydrocarbon groups having 1 to 18 carbon atoms represented by X ^III3 .
Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by R ^II1 include a phenylene group and a naphthylene group.
Alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, alkoxy groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and alicyclic groups that are substituents of alkyl groups represented by R ^II2 and R ^II3 A halogen atom, an alkyl group, an alkylcarbonyl group that are substituents of the hydrocarbon group of the formula, and a halogen atom and an alkoxy group that are the substituents of the aromatic hydrocarbon group are represented by R ^b4 to R ^b6 of the above formula (b2-1). The same is mentioned.
Halogen atoms represented by ^RII4 include fluorine, chlorine, bromine and iodine atoms.
The alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R ^II4 includes an alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R ^a8 . The same can be mentioned.

Examples of structural units containing cations in formula (II-1-1) include structural units represented below.

Organic anions represented by A ⁻ include sulfonate anions, sulfonylimide anions, sulfonylmethide anions and carboxylate anions. The organic anion represented by A ⁻ is preferably a sulfonate anion, more preferably an anion contained in a salt represented by formula (B1) described later.

Sulfonylimide anions represented by A ⁻ include the following.

Examples of the structural unit (II-1) include structural units represented below.

When the resin (A) contains the structural unit (II), the content of the structural unit (II) is preferably 1 to 20 mol% of the total structural units of the resin (A), and more It is preferably 2 to 15 mol %, more preferably 3 to 10 mol %.

The resin (A) is preferably a resin composed of the structural unit (I), the structural unit (a1) and the structural unit (s), that is, the compound (I), the monomer (a1) and the monomer (s). It is a polymer.
Structural unit (a1) is preferably at least one selected from structural unit (a1-1) and structural unit (a1-2) (preferably the structural unit having a cyclohexyl group or a cyclopentyl group), more preferably a structural unit ( a1-1) or at least two selected from the structural unit (a1-1) and the structural unit (a1-2) (preferably the structural unit having a cyclohexyl group or a cyclopentyl group).
Structural unit (s) is preferably at least one of structural unit (a2) and structural unit (a3). Structural unit (a2) is preferably a structural unit represented by formula (a2-1). Structural unit (a3) is preferably a structural unit represented by formula (a3-1-1) to formula (a3-1-4), formula (a3-2-1) to formula (a3-2-4) and at least one selected from structural units represented by formulas (a3-4-1) to (a3-4-2).

Each structural unit that constitutes the resin (A) may be used alone or in combination of two or more. Using a monomer that induces these structural units, it is produced by a known polymerization method (e.g., radical polymerization method). can do. The content of each structural unit in the resin (A) can be adjusted by adjusting the amount of monomer used for polymerization.
The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,500 or more, still more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less, further preferably is 15,000 or less). As used herein, the weight average molecular weight is a value obtained by gel permeation chromatography under the conditions described in Examples.

<Resin (X) other than resin (A)>
The resist composition of the present invention may contain a resin other than resin (A). Examples of such a resin include a resin containing the structural unit (a4) (hereinafter sometimes referred to as "resin (X)").
Structural units that the resin (X) may further include structural units (a1), structural units (a2), structural units (a3), structural units (a5) and other known structural units.
More preferably, the resin (X) is a resin comprising structural units (a4) and/or structural units (a5).
When the resin (X) contains the structural unit (a4), the content thereof is preferably 40 mol% or more, more preferably 45 mol% or more, and 50 mol% or more, based on the total structural units of the resin (X). is more preferred.
When the resin (X) contains the structural unit (a5), its content is preferably 10 to 60 mol%, more preferably 20 to 55 mol%, more preferably 25 to 50 mol % is more preferred.

Each structural unit that constitutes the resin (X) may be used alone or in combination of two or more. Using a monomer that induces these structural units, the resin (X) is produced by a known polymerization method (e.g., radical polymerization method). can do. The content of each structural unit in the resin (X) can be adjusted by adjusting the amount of the monomer used for polymerization.
The weight average molecular weight of resin (X) is preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less). The means for measuring the weight-average molecular weight of resin (X) is the same as for resin (A).
When the resist composition contains resin (X), its content is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, relative to 100 parts by mass of resin (A). It is preferably 1 to 40 parts by mass, particularly preferably 2 to 30 parts by mass.

The total content of the resin (A) and the resin other than the resin (A) is preferably 80% by mass or more and 99% by mass or less, preferably 90% by mass or more and 99% by mass or less, relative to the solid content of the resist composition. . The solid content and resin content of the resist composition can be measured by known analytical means such as liquid chromatography or gas chromatography.

<Acid generator (B)>
Acid generators are classified into nonionic and ionic acid generators, and any of them may be used as the acid generator (B) of the resist composition of the present invention. Nonionic acid generators include organic halides, sulfonate esters (eg, 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4-sulfonate), sulfones (eg, disulfone, ketosulfone, sulfonyldiazomethane) and the like. Typical ionic acid generators are onium salts containing onium cations (eg, diazonium salts, phosphonium salts, sulfonium salts, iodonium salts). The anions of the onium salts include sulfonate anions, sulfonylimide anions, sulfonylmethide anions, and the like.

Examples of the acid generator (B) include JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, US Pat. No. 3,779,778, US Pat. A compound that generates an acid upon exposure to radiation as described in 1. above can be used. Moreover, you may use the compound manufactured by the well-known method. The acid generator (B) may be used alone or in combination of two or more.

［式（Ｂ１）中、
Ｑ^１及びＱ^２は、それぞれ独立に、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。
Ｌ^ｂ１は、置換基を有していてもよい炭素数１～２４の２価の飽和炭化水素基を表し、該２価の飽和炭化水素基に含まれる－ＣＨ_２－は、－Ｏ－又は－ＣＯ－に置き換わっていてもよく、該２価の飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基で置換されていてもよい。
Ｙは、水素原子又は置換基を有していてもよい炭素数３～１８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－ＣＨ_２－は、－Ｏ－、－ＳＯ_２－又は－ＣＯ－に置き換わっていてもよい。
Ｚ^＋は、有機カチオンを表す。］ The acid generator (B) is preferably a fluorine-containing acid generator, more preferably a salt represented by formula (B1) (hereinafter sometimes referred to as "acid generator (B1)").

[In the formula (B1),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents an optionally substituted C 1-24 divalent saturated hydrocarbon group, and —CH ₂ — contained in the divalent saturated hydrocarbon group is —O— or -CO- may be substituted, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group.
Y represents a hydrogen atom or an optionally substituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, and —CH ₂ — contained in the alicyclic hydrocarbon group is —O—, —SO ₂ — or —CO— may be substituted.
Z ⁺ represents an organic cation. ]

The perfluoroalkyl groups for Q ¹ and Q ² include trifluoromethyl, perfluoroethyl, perfluoropropyl, perfluoroisopropyl, perfluorobutyl, perfluorosec-butyl, perfluorotert-butyl, perfluoropentyl and perfluoro A hexyl group and the like can be mentioned.
Q ¹ and Q ² are each independently preferably a fluorine atom or a trifluoromethyl group, and more preferably both a fluorine atom.

The divalent saturated hydrocarbon group for L ^b1 includes a linear alkanediyl group, a branched alkanediyl group, and a monocyclic or polycyclic bivalent alicyclic saturated hydrocarbon group. A group formed by combining two or more of the groups may also be used.
Specifically, methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1 ,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group , tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group and heptadecane-1,17-diyl group. alkanediyl group;
ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane- Branched alkanediyl groups such as 1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group;
monocyclic 2 which is a cycloalkanediyl group such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; alicyclic saturated hydrocarbon group;
Polycyclic divalent alicyclic saturated hydrocarbons such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group and the like.

［式（ｂ１－１）中、
Ｌ^ｂ２は、単結合又は炭素数１～２２の２価の飽和炭化水素基を表し、該飽和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。
Ｌ^ｂ３は、単結合又は炭素数１～２２の２価の飽和炭化水素基を表し、該飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置換されていてもよく、該飽和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に置き換わっていてもよい。
ただし、Ｌ^ｂ２とＬ^ｂ３との炭素数合計は、２２以下である。
式（ｂ１－２）中、
Ｌ^ｂ４は、単結合又は炭素数１～２２の２価の飽和炭化水素基を表し、該飽和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。
Ｌ^ｂ５は、単結合又は炭素数１～２２の２価の飽和炭化水素基を表し、該飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置換されていてもよく、該飽和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に置き換わっていてもよい。
ただし、Ｌ^ｂ４とＬ^ｂ５との炭素数合計は、２２以下である。
式（ｂ１－３）中、
Ｌ^ｂ６は、単結合又は炭素数１～２３の２価の飽和炭化水素基を表し、該飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置換されていてもよい。
Ｌ^ｂ７は、単結合又は炭素数１～２３の２価の飽和炭化水素基を表し、該飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置換されていてもよく、該飽和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に置き換わっていてもよい。
ただし、Ｌ^ｂ６とＬ^ｂ７との炭素数合計は、２３以下である。］ The group in which —CH ₂ — contained in the divalent saturated hydrocarbon group of L ^b1 is replaced with —O— or —CO— is, for example, any one of formulas (b1-1) to (b1-3). The group represented by is mentioned. In formulas (b1-1) to (b1-3) and specific examples below, * represents a bond with -Y.

[In formula (b1-1),
L ^b2 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom.
L ^b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and the saturated A methylene group contained in the hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.
However, the total number of carbon atoms of L ^b2 and L ^b3 is 22 or less.
In formula (b1-2),
L ^b4 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom.
L ^b5 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and the saturated A methylene group contained in the hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.
However, the total number of carbon atoms of L ^b4 and L ^b5 is 22 or less.
In formula (b1-3),
L ^b6 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group.
L ^b7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and the saturated A methylene group contained in the hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.
However, the total number of carbon atoms of L ^b6 and L ^b7 is 23 or less. ]

In formulas (b1-1) to (b1-3), when the methylene group contained in the saturated hydrocarbon group is replaced with an oxygen atom or a carbonyl group, the number of carbon atoms before replacement is the carbon of the saturated hydrocarbon group. number.
As the divalent saturated hydrocarbon group, the same divalent saturated hydrocarbon group as L ^b1 can be mentioned.

L ^b2 is preferably a single bond.
L ^b3 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms.
L ^b4 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom.
L ^b5 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^b6 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom.
L ^b7 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group; A methylene group contained in the divalent saturated hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.

The group in which —CH ₂ — contained in the divalent saturated hydrocarbon group of L ^b1 is replaced with —O— or —CO— is a group represented by formula (b1-1) or formula (b1-3) is preferred.

［式（ｂ１－４）中、
Ｌ^ｂ８は、単結合又は炭素数１～２２の２価の飽和炭化水素基を表し、該飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置換されていてもよい。
式（ｂ１－５）中、
Ｌ^ｂ９は、炭素数１～２０の２価の飽和炭化水素基を表す。
Ｌ^ｂ１０は、単結合又は炭素数１～１９の２価の飽和炭化水素基を表し、該２価の飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置換されていてもよい。
ただし、Ｌ^ｂ９及びＬ^ｂ１０の合計炭素数は２０以下である。
式（ｂ１－６）中、
Ｌ^ｂ１１は、炭素数１～２１の２価の飽和炭化水素基を表す。
Ｌ^ｂ１２は、単結合又は炭素数１～２０の２価の飽和炭化水素基を表し、該２価の飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置換されていてもよい。
ただし、Ｌ^ｂ１１及びＬ^ｂ１２の合計炭素数は２１以下である。
式（ｂ１－７）中、
Ｌ^ｂ１３は、炭素数１～１９の２価の飽和炭化水素基を表す。
Ｌ^ｂ１４は、単結合又は炭素数１～１８の２価の飽和炭化水素基を表す。
Ｌ^ｂ１５は、単結合又は炭素数１～１８の２価の飽和炭化水素基を表し、該２価の飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置換されていてもよい。
ただし、Ｌ^ｂ１３～Ｌ^ｂ１５の合計炭素数は１９以下である。
式（ｂ１－８）中、
Ｌ^ｂ１６は、炭素数１～１８の２価の飽和炭化水素基を表す。
Ｌ^ｂ１７は、炭素数１～１８の２価の飽和炭化水素基を表す。
Ｌ^ｂ１８は、単結合又は炭素数１～１７の２価の飽和炭化水素基を表し、該２価の飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置換されていてもよい。
ただし、Ｌ^ｂ１６～Ｌ^ｂ１８の合計炭素数は１９以下である。］ Examples of formula (b1-1) include groups represented by formulas (b1-4) to (b1-8).

[In formula (b1-4),
L ^b8 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group.
In formula (b1-5),
L ^b9 represents a divalent saturated hydrocarbon group having 1 to 20 carbon atoms.
L ^b10 represents a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. .
However, the total carbon number of L ^b9 and L ^b10 is 20 or less.
In formula (b1-6),
L ^b11 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms.
L ^b12 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. .
However, the total carbon number of L ^b11 and L ^b12 is 21 or less.
In formula (b1-7),
L ^b13 represents a divalent saturated hydrocarbon group having 1 to 19 carbon atoms.
L ^b14 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms.
L ^b15 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. .
However, the total carbon number of L ^b13 to L ^b15 is 19 or less.
In formula (b1-8),
L ^b16 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms.
L ^b17 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms.
L ^b18 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. .
However, the total carbon number of L ^b16 to L ^b18 is 19 or less. ]

L ^b8 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms.
L ^b9 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^b10 is preferably a single bond or a C 1-19 divalent saturated hydrocarbon group, more preferably a single bond or a C 1-8 divalent saturated hydrocarbon group.
L ^b11 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^b12 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^b13 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms.
L ^b14 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms.
L ^b15 is preferably a single bond or a C 1-18 divalent saturated hydrocarbon group, more preferably a single bond or a C 1-8 divalent saturated hydrocarbon group.
L ^b16 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms.
L ^b17 is preferably a divalent saturated hydrocarbon group having 1 to 6 carbon atoms.
L ^b18 is preferably a single bond or a C 1-17 divalent saturated hydrocarbon group, more preferably a single bond or a C 1-4 divalent saturated hydrocarbon group.

［式（ｂ１－９）中、
Ｌ^ｂ１９は、単結合又は炭素数１～２３の２価の飽和炭化水素基を表し、該２価の飽和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。
Ｌ^ｂ２０は、単結合又は炭素数１～２３の２価の飽和炭化水素基を表し、該２価の飽和炭化水素基に含まれる水素原子はフッ素原子、ヒドロキシ基又はアシルオキシ基に置換されていてもよい。該アシルオキシ基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよく、該アシルオキシ基に含まれる水素原子は、ヒドロキシ基に置換されていてもよい。
ただし、Ｌ^ｂ１９及びＬ^ｂ２０の合計炭素数は２３以下である。
式（ｂ１－１０）中、
Ｌ^ｂ２１は、単結合又は炭素数１～２１の２価の飽和炭化水素基を表し、該２価の飽和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。
Ｌ^ｂ２２は、単結合又は炭素数１～２１の２価の飽和炭化水素基を表す。
Ｌ^ｂ２３は、単結合又は炭素数１～２１の２価の飽和炭化水素基を表し、該２価の飽和炭化水素基に含まれる水素原子は、フッ素原子、ヒドロキシ基又はアシルオキシ基に置換されていてもよい。該アシルオキシ基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよく、該アシルオキシ基に含まれる水素原子は、ヒドロキシ基に置換されていてもよい。
ただし、Ｌ^ｂ２１～Ｌ^ｂ２３の合計炭素数は２１以下である。
式（ｂ１－１１）中、
Ｌ^ｂ２４は、単結合又は炭素数１～２０の２価の飽和炭化水素基を表し、該２価の飽和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。
Ｌ^ｂ２５は、炭素数１～２１の２価の飽和炭化水素基を表す。
Ｌ^ｂ２６は、単結合又は炭素数１～２０の２価の飽和炭化水素基を表し、該２価の飽和炭化水素基に含まれる水素原子は、フッ素原子、ヒドロキシ基又はアシルオキシ基に置換されていてもよい。該アシルオキシ基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよく、該アシルオキシ基に含まれる水素原子は、ヒドロキシ基に置換されていてもよい。
ただし、Ｌ^ｂ２４～Ｌ^ｂ２６の合計炭素数は２１以下である。］ Examples of formula (b1-3) include groups represented by formulas (b1-9) to (b1-11).

[In formula (b1-9),
L ^b19 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom.
L ^b20 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, a hydrogen atom contained in the divalent saturated hydrocarbon group being substituted with a fluorine atom, a hydroxy group or an acyloxy group; good too. A methylene group contained in the acyloxy group may be substituted with an oxygen atom or a carbonyl group, and a hydrogen atom contained in the acyloxy group may be substituted with a hydroxy group.
However, the total carbon number of L ^b19 and L ^b20 is 23 or less.
In formula (b1-10),
L ^b21 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom.
L ^b22 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms.
L ^b23 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group is substituted with a fluorine atom, a hydroxy group or an acyloxy group. may A methylene group contained in the acyloxy group may be substituted with an oxygen atom or a carbonyl group, and a hydrogen atom contained in the acyloxy group may be substituted with a hydroxy group.
However, the total carbon number of L ^b21 to L ^b23 is 21 or less.
In formula (b1-11),
L ^b24 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom.
L ^b25 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms.
L ^b26 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group is substituted with a fluorine atom, a hydroxy group or an acyloxy group. may A methylene group contained in the acyloxy group may be substituted with an oxygen atom or a carbonyl group, and a hydrogen atom contained in the acyloxy group may be substituted with a hydroxy group.
However, the total carbon number of L ^b24 to L ^b26 is 21 or less. ]

In formulas (b1-9) to (b1-11), when a hydrogen atom contained in a divalent saturated hydrocarbon group is substituted with an acyloxy group, the number of carbon atoms in the acyloxy group, CO in the ester bond and The number of carbon atoms in the divalent saturated hydrocarbon group includes the number of O atoms.

Acyloxy groups include acetyloxy, propionyloxy, butyryloxy, cyclohexylcarbonyloxy, and adamantylcarbonyloxy groups.

Among the groups represented by formula (b1-1), the groups represented by formula (b1-4) include the following.

Among the groups represented by formula (b1-1), the groups represented by formula (b1-5) include the following.

Among the groups represented by formula (b1-1), the groups represented by formula (b1-6) include the following.

Among the groups represented by formula (b1-1), the groups represented by formula (b1-7) include the following.

Among the groups represented by formula (b1-1), the groups represented by formula (b1-8) include the following.

Examples of the group represented by formula (b1-2) include the following.

Among the groups represented by formula (b1-3), the groups represented by formula (b1-9) include the following.

Among the groups represented by formula (b1-3), the groups represented by formula (b1-10) include the following.

Among the groups represented by formula (b1-3), the groups represented by formula (b1-11) include the following.

The alicyclic hydrocarbon group represented by Y includes groups represented by formulas (Y1) to (Y11) and formulas (Y36) to (Y38).
When —CH ₂ — contained in the alicyclic hydrocarbon group represented by Y is replaced with —O—, —SO ₂ — or —CO—, the number thereof may be one, or two or more. . Such groups include groups represented by formulas (Y12) to (Y35), formula (Y39), and formula (Y40).

That is, in Y, two hydrogen atoms contained in an alicyclic hydrocarbon group are each replaced with an oxygen atom, and the two oxygen atoms form a ketal ring together with an alkanediyl group having 1 to 8 carbon atoms. Alternatively, it may contain a structure in which oxygen atoms are respectively bonded to different carbon atoms. However, when forming a spiro ring of formulas (Y28) to (Y33), formula (Y39), formula (Y40), etc., the alkanediyl group between two oxygens must have one or more fluorine atoms. is preferred. Among the alkanediyl groups contained in the ketal structure, those in which the methylene group adjacent to the oxygen atom is not substituted with a fluorine atom are preferred.

Among them, preferably a group represented by any one of formulas (Y1) to (Y20), formula (Y30), formula (Y31), formula (Y39) or formula (Y40), more preferably formula ( Y11), formula (Y15), formula (Y16), formula (Y19), formula (Y20), formula (Y30), formula (Y31), formula (Y39) or a group represented by formula (Y40). and more preferably groups represented by formula (Y11), formula (Y15), formula (Y30), formula (Y39) or formula (Y40).

Substituents for the alicyclic hydrocarbon group represented by Y include a halogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, an alkyl group containing a hydroxy group and having 1 to 12 carbon atoms, and an alkyl group having 3 to 16 carbon atoms. an alicyclic hydrocarbon group, an alkoxy group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, an acyl group having 2 to 4 carbon atoms, a glycidyloxy group, or —(CH ₂ ) _ja —O—CO—R ^b1 group (wherein R ^b1 is an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, or a represents an aromatic hydrocarbon group, and ja represents an integer of 0 to 4).

The hydroxy group-containing alkyl group includes a hydroxymethyl group, a hydroxyethyl group, and the like.
Alkoxy groups include methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, decyloxy and dodecyloxy groups.
Aromatic hydrocarbon groups include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group and phenanthryl group; tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, p-tert Alkyl-aryl groups such as -butylphenyl group and 2-methyl-6-ethylphenyl group; and cycloalkyl-aryl groups such as p-adamantylphenyl group.
Aralkyl groups include benzyl, phenethyl, phenylpropyl, naphthylmethyl and naphthylethyl groups.
Acyl groups include, for example, acetyl, propionyl and butyryl groups.
Halogen atoms include fluorine, chlorine, bromine and iodine atoms.

Examples of Y include the following.

Y is preferably an optionally substituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, more preferably an optionally substituted adamantyl group, constituting these groups The methylene group may be replaced with an oxygen atom, a sulfonyl group or a carbonyl group. Y is more preferably an adamantyl group, a hydroxyadamantyl group, an oxoadamantyl group, or a group represented below.

Examples of the sulfonate anion in the salt represented by formula (B1) include anions represented by formulas (B1-A-1) to (B1-A-55) [hereinafter referred to as "anion (B1 -A-1)”, etc. ] is preferable, formula (B1-A-1) ~ formula (B1-A-4), formula (B1-A-9), formula (B1-A-10), formula (B1-A-24) ~ formula (B1-A-33), formula (B1-A-36) ~ formula (B1-A-40), represented by any of formula (B1-A-47) ~ formula (B1-A-55) Anions are more preferred.

Here, R ⁱ² to R ⁱ⁷ are, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group.
R ⁱ⁸ is, for example, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a combination of these A formed group, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group.
L ⁴⁴ represents a single bond or an alkanediyl group having 1 to 4 carbon atoms.
Q ¹ and Q ² are the same as above.
Specific examples of the sulfonate anion in the salt represented by formula (B1) include anions described in JP-A-2010-204646.

Preferred sulfonate anions in the salt represented by formula (B1) include anions represented by formulas (B1a-1) to (B1a-34), respectively.

Among them, formula (B1a-1) ~ formula (B1a-3) and formula (B1a-7) ~ formula (B1a-16), formula (B1a-18), formula (B1a-19), formula (B1a-22 ) to formula (B1a-34) are preferred.
The organic cations of Z ⁺ include organic onium cations such as organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, organic phosphonium cations, etc., preferably organic sulfonium cations or organic iodonium cations. and more preferably an arylsulfonium cation.
Specific examples include the same organic cations as those exemplified for the structural unit (II).

The acid generator (B1) is a combination of the above sulfonate anion and the above organic cation, and these can be combined arbitrarily. As the acid generator (B1), anions and cations (b2 -1).

Examples of the acid generator (B1) include those represented by formulas (B1-1) to (B1-48), and among them, formulas (B1-1) to (B1-3), formula (B1 -5) ~ Formula (B1-7), Formula (B1-11) ~ Formula (B1-14), Formula (B1-17), Formula (B1-20) ~ Formula (B1-26), Formula (B1- 29), and those represented by formulas (B1-31) to (B1-48) are preferable.

The acid generator (B) may contain an acid generator other than the acid generator (B1).
In the resist composition of the present invention, the acid generator (B1) may be contained singly or in combination. Among them, the acid generator (B1) preferably contains two or more acid generators. The content of the acid generator (B1) is preferably 50% by mass or more, more preferably 70% by mass or more, and still more preferably 90% by mass or more, relative to the total amount of the acid generator (B). Especially preferred is the agent (B1) only.
The content of the acid generator (B) is preferably 1 part by mass or more (more preferably 3 parts by mass or more), preferably 40 parts by mass or less (more preferably 35 parts by mass), relative to 100 parts by mass of the resin (A). part and below).

<Solvent (E)>
The content of the solvent (E) is usually 90% by mass or more, preferably 92% by mass or more, more preferably 94% by mass or more, and 99.9% by mass or less, preferably 99% by mass or less in the resist composition. is. The content of the solvent (E) can be measured by known analytical means such as liquid chromatography or gas chromatography.

Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone; cyclic esters such as γ-butyrolactone; One type of the solvent (E) may be contained alone, or two or more types may be contained.

<Quencher (C)>
The resist composition of the present invention may contain a quencher having a structure different from that of compound (I) (hereinafter sometimes referred to as "quencher (C)"). The quencher (C) includes a basic nitrogen-containing organic compound having a structure different from that of the compound (I) or a salt that generates an acid with a weaker acidity than the acid generator (B).

<Basic nitrogen-containing organic compound>
Basic nitrogen-containing organic compounds include amines and ammonium salts. Amines include aliphatic amines and aromatic amines. Aliphatic amines include primary, secondary and tertiary amines.

Specifically, 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, hexylamine , heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, 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, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino- 3,3′-diethyldiphenylmethane, 2,2′-methylenebisaniline, imidazole, 4-methylimidazole, pyridine, 4-methylpyridine, 1,2-di(2-pyridyl)ethane, 1,2-di(4 -pyridyl)ethane, 1,2-di(2-pyridyl)ethene, 1,2-di(4-pyridyl)ethene, 1,3-di(4-pyridyl)propane, 1,2-di(4-pyridyl) oxy)ethane, di(2-pyridyl)ketone, 4,4'-dipyridylsulfide, 4,4'-dipyridyldisulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine, bipyridine and the like. , preferably diisopropylaniline, and particularly preferably 2,6-diisopropylaniline.

Ammonium salts include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-(trifluoromethyl)phenyltrimethyl ammonium hydroxide, tetra-n-butylammonium salicylate and choline;

<Salts that generate weakly acidic acids>
The acidity of a salt that generates an acid that is weaker than the acid generated from the acid generator is indicated by the acid dissociation constant (pKa). The salt that generates an acid weaker in acidity than the acid generated from the acid generator is a salt with a pKa of -3<pKa, preferably -1<pKa<7. and more preferably a salt with 0<pKa<5. Salts that generate an acid weaker than the acid generated from the acid generator include salts represented by the following formulas, weak acid inner salts described in JP-A-2015-147926, and JP-A-2012-229206. Examples include salts described in JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-39502 and JP-A-2011-191745.

The content of the quencher (C) in the solid content of the resist composition is preferably 0.01 to 5% by mass, more preferably 0.01 to 4% by mass, and particularly preferably 0.01 to 3%. % by mass.

<Other ingredients>
If necessary, the resist composition of the present invention may contain components other than the components described above (hereinafter sometimes referred to as "other components (F)"). Other components (F) are not particularly limited, and additives known in the field of resists, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc., can be used.

<Preparation of resist composition>
The resist composition of the present invention comprises a resin (A), an acid generator and a compound (I), and optionally a resin (X), a quencher (C), a solvent (E) and other components ( It can be prepared by mixing F). The mixing order is arbitrary and not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40° C. depending on the type of resin or the like and the solubility of the resin or the like in the solvent (E). An appropriate mixing time can be selected from 0.5 to 24 hours depending on the mixing temperature. The mixing means is also not particularly limited, and stirring and mixing can be used.
After mixing each component, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm.

<Method for producing resist pattern>
The method for producing a resist pattern of the present invention comprises:
(1) a step of applying the resist composition of the present invention onto a substrate;
(2) a step of drying the applied composition to form a composition layer;
(3) exposing the composition layer;
(4) heating the exposed composition layer; and (5) developing the heated composition layer.

The coating of the resist composition on the substrate can be carried out using a commonly used device such as a spin coater. Examples of substrates include inorganic substrates such as silicon wafers. Before applying the resist composition, the substrate may be washed, or an antireflection film or the like may be formed on the substrate.

By drying the applied composition, the solvent is removed and a composition layer is formed. Drying is carried out, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking), or by using a decompression device. The heating temperature is preferably 50 to 200° C., and the heating time is preferably 10 to 180 seconds. The pressure for drying under reduced pressure is preferably about 1 to 1.0×10 ⁵ Pa.

The resulting composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. As the exposure light source, a KrF excimer laser (wavelength: 248 nm), an ArF excimer laser (wavelength: 193 nm), an F ₂ excimer laser (wavelength: 157 nm) that emits a laser beam in the ultraviolet region, a solid-state laser source (YAG or semiconductor laser etc.) and emits harmonic laser light in the far ultraviolet region or vacuum ultraviolet region by wavelength conversion, electron beam, and extreme ultraviolet light (EUV). can be done. In this specification, these irradiations with radiation may be collectively referred to as "exposure". During exposure, exposure is usually performed through a mask corresponding to the desired pattern. When the exposure light source is an electron beam, exposure may be performed by direct drawing without using a mask.

The exposed composition layer is subjected to a heat treatment (so-called post-exposure bake) in order to promote the deprotection reaction at the acid-labile groups. The heating temperature is usually about 50 to 200°C, preferably about 70 to 150°C.

The composition layer after heating is usually developed using a developer using a developing device. The developing method includes a dipping method, a paddle method, a spraying method, a dynamic dispensing method, and the like. The developing temperature is preferably 5 to 60° C., and the developing time is preferably 5 to 300 seconds. A positive resist pattern or a negative resist pattern can be produced by selecting the type of developer as follows.

When producing a positive resist pattern from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be any of various alkaline aqueous solutions used in this field. Examples thereof include aqueous solutions of tetramethylammonium hydroxide and (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline). The alkaline developer may contain a surfactant.
After development, the resist pattern is preferably washed with ultrapure water, and then water remaining on the substrate and pattern is removed.

When producing a negative resist pattern from the resist composition of the present invention, a developer containing an organic solvent (hereinafter sometimes referred to as "organic developer") is used as the developer.
Examples of organic solvents contained in the organic developer include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycols such as propylene glycol monomethyl ether. ether solvents; amide solvents such as N,N-dimethylacetamide; aromatic hydrocarbon solvents such as anisole;
The content of the organic solvent in the organic developer is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and still more preferably substantially only the organic solvent.
Among them, as the organic developer, a developer containing butyl acetate and/or 2-heptanone is preferable. The total content of butyl acetate and 2-heptanone in the organic developer is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and substantially contains butyl acetate and/or 2-heptanone. - more preferably only heptanone.
The organic developer may contain a surfactant. In addition, the organic developer may contain a trace amount of water.
During development, the development may be stopped by replacing the organic developer with a solvent of a different type.

It is preferable to wash the resist pattern after development with a rinsing liquid. The rinse liquid is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent.
After cleaning, it is preferable to remove the rinse liquid remaining on the substrate and pattern.

<Application>
The resist composition of the present invention is a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure. It is suitable as a resist composition for line (EB) exposure or as a resist composition for EUV exposure, and is useful for microfabrication of semiconductors.

EXAMPLES The present invention will be described more specifically with reference to examples. In the examples, "%" and "parts" 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 under the following conditions.
Apparatus: HLC-8120GPC type (manufactured by Tosoh Corporation)
Column: TSKgel Multipore H _XL -M x 3 + 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 measuring the molecular peak using mass spectrometry (LC: Agilent Model 1100, MASS: Agilent Model LC/MSD). In the examples below, the value of this molecular peak is indicated by "MASS".

式（Ｉ－４－ａ）で表される化合物１０部、カルボニルジイミダゾール６．２部及びクロロホルム５０部を混合し、２３℃で３０分間攪拌した。得られた混合溶液に、式（Ｉ－４－ｂ）で表される化合物５部を添加し、６０℃で３時間攪拌した後、２３℃まで冷却した。得られた反応物に、イオン交換水５０部を混合して２３℃で３０分間攪拌し、分液することにより有機層を回収した。この水洗の操作を３回行った。得られた有機層を濃縮した後、回収された濃縮残渣をカラム（シリカゲル６０Ｎ（球状、中性）１００－２１０μｍ；関東化学（株）製、展開溶媒：クロロホルム／酢酸エチル＝１／４）分取することにより、式（Ｉ－４）で表される化合物８．２５部を得た。
ＭＳ（質量分析）：３７６．１ ［Ｍ＋Ｈ］^＋ Synthesis Example 1 [Synthesis of compound represented by formula (I-4)]

10 parts of the compound represented by formula (I-4-a), 6.2 parts of carbonyldiimidazole and 50 parts of chloroform were mixed and stirred at 23° C. for 30 minutes. 5 parts of the compound represented by the formula (I-4-b) was added to the resulting mixed solution, stirred at 60°C for 3 hours, and then cooled to 23°C. The obtained reactant was mixed with 50 parts of ion-exchanged water, stirred at 23° C. for 30 minutes, and separated to recover an organic layer. This washing operation was performed three times. After concentrating the obtained organic layer, the collected concentrated residue was applied to a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Ltd., developing solvent: chloroform/ethyl acetate=1/4). By extraction, 8.25 parts of the compound represented by the formula (I-4) was obtained.
MS (mass spectroscopy): 376.1 [M+H] ⁺

式（Ｉ－１３－ａ）で表される化合物８部、テトラヒドロフラン４０部及びピリジン３．４７部を混合し、２３℃で３０分間攪拌した。得られた混合物を５℃まで冷却した後、式（Ｉ－１３－ｂ）で表される化合物５．２部を添加し、２３℃に昇温後、２３℃で１８時間攪拌した。得られた反応物に、酢酸エチル１８０部及び５％塩酸６５部を混合して２３℃で３０分間攪拌し、分液することにより有機層を回収した。得られた有機層に、イオン交換水４０部を混合して２３℃で３０分間攪拌し、分液することにより有機層を回収した。この水洗の操作を３回行った。得られた有機層を濃縮した後、回収された濃縮残渣をカラム（シリカゲル６０Ｎ（球状、中性）１００－２１０μｍ；関東化学（株）製、展開溶媒：ｎ－ヘプタン／酢酸エチル＝１／１）分取することにより、式（Ｉ－１３）で表される化合物９．２１部を得た。
ＭＳ（質量分析）：３６０．１ ［Ｍ＋Ｈ］^＋ Synthesis Example 2 [Synthesis of compound represented by formula (I-13)]

8 parts of the compound represented by formula (I-13-a), 40 parts of tetrahydrofuran and 3.47 parts of pyridine were mixed and stirred at 23° C. for 30 minutes. After cooling the obtained mixture to 5° C., 5.2 parts of the compound represented by the formula (I-13-b) was added, the temperature was raised to 23° C., and the mixture was stirred at 23° C. for 18 hours. The obtained reactant was mixed with 180 parts of ethyl acetate and 65 parts of 5% hydrochloric acid, and the mixture was stirred at 23° C. for 30 minutes and separated to recover an organic layer. The obtained organic layer was mixed with 40 parts of ion-exchanged water, stirred at 23° C. for 30 minutes, and separated to recover the organic layer. This washing operation was performed three times. After concentrating the obtained organic layer, the collected concentrated residue was applied to a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Ltd., developing solvent: n-heptane/ethyl acetate=1/1). ) to obtain 9.21 parts of the compound represented by the formula (I-13).
MS (mass spectroscopy): 360.1 [M+H] ⁺

式（Ｉ－４－ａ）で表される化合物１０部、カルボニルジイミダゾール６．２部及びクロロホルム５０部を混合し、２３℃で３０分間攪拌した。得られた混合溶液に、式（Ｉ－１０－ｂ）で表される化合物５．８５部を添加し、６０℃で３時間攪拌した後、２３℃まで冷却した。得られた反応物に、イオン交換水５０部を混合して２３℃で３０分間攪拌し、分液することにより有機層を回収した。この水洗の操作を３回行った。得られた有機層を濃縮した後、回収された濃縮残渣をカラム（シリカゲル６０Ｎ（球状、中性）１００－２１０μｍ；関東化学（株）製、展開溶媒：クロロホルム／酢酸エチル＝１／４）分取することにより、式（Ｉ－１０）で表される化合物７．６４部を得た。
ＭＳ（質量分析）：３９８．１ ［Ｍ＋Ｈ］^＋ Synthesis Example 3 [Synthesis of compound represented by formula (I-10)]

10 parts of the compound represented by formula (I-4-a), 6.2 parts of carbonyldiimidazole and 50 parts of chloroform were mixed and stirred at 23° C. for 30 minutes. To the resulting mixed solution, 5.85 parts of the compound represented by formula (I-10-b) was added, stirred at 60°C for 3 hours, and then cooled to 23°C. The obtained reactant was mixed with 50 parts of ion-exchanged water, stirred at 23° C. for 30 minutes, and separated to recover an organic layer. This washing operation was performed three times. After concentrating the obtained organic layer, the collected concentrated residue was applied to a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Ltd., developing solvent: chloroform/ethyl acetate=1/4). By extraction, 7.64 parts of the compound represented by the formula (I-10) was obtained.
MS (mass spectroscopy): 398.1 [M+H] ⁺

式（Ｉ－４－ａ）で表される化合物１０部、カルボニルジイミダゾール６．２部及びクロロホルム５０部を混合し、２３℃で３０分間攪拌した。得られた混合溶液に、式（Ｉ－１１－ｂ）で表される化合物６．３９部を添加し、６０℃で３時間攪拌した後、２３℃まで冷却した。得られた反応物に、イオン交換水５０部を混合して２３℃で３０分間攪拌し、分液することにより有機層を回収した。この水洗の操作を３回行った。得られた有機層を濃縮した後、回収された濃縮残渣をカラム（シリカゲル６０Ｎ（球状、中性）１００－２１０μｍ；関東化学（株）製、展開溶媒：クロロホルム／酢酸エチル＝１／２）分取することにより、式（Ｉ－１１）で表される化合物７．８８部を得た。
ＭＳ（質量分析）：４１２．０ ［Ｍ＋Ｈ］^＋ Synthesis Example 4 [Synthesis of Compound Represented by Formula (I-11)]

10 parts of the compound represented by formula (I-4-a), 6.2 parts of carbonyldiimidazole and 50 parts of chloroform were mixed and stirred at 23° C. for 30 minutes. To the obtained mixed solution, 6.39 parts of the compound represented by the formula (I-11-b) was added, stirred at 60°C for 3 hours, and then cooled to 23°C. The obtained reactant was mixed with 50 parts of ion-exchanged water, stirred at 23° C. for 30 minutes, and separated to recover an organic layer. This washing operation was performed three times. After concentrating the obtained organic layer, the collected concentrated residue was applied to a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Ltd., developing solvent: chloroform/ethyl acetate=1/2). By extraction, 7.88 parts of the compound represented by the formula (I-11) was obtained.
MS (mass spectroscopy): 412.0 [M+H] ⁺

式（Ｉ－４－ａ）で表される化合物１０部、カルボニルジイミダゾール６．２部及びクロロホルム５０部を混合し、２３℃で３０分間攪拌した。得られた混合溶液に、式（Ｉ－１２－ｂ）で表される化合物６．４８部を添加し、６０℃で３時間攪拌した後、２３℃まで冷却した。得られた反応物に、イオン交換水５０部を混合して２３℃で３０分間攪拌し、分液することにより有機層を回収した。この水洗の操作を３回行った。得られた有機層を濃縮した後、回収された濃縮残渣をカラム（シリカゲル６０Ｎ（球状、中性）１００－２１０μｍ；関東化学（株）製、展開溶媒：クロロホルム／酢酸エチル＝１／２）分取することにより、式（Ｉ－１２）で表される化合物６．２２部を得た。
ＭＳ（質量分析）：４１４．１ ［Ｍ＋Ｈ］^＋ Synthesis Example 5 [Synthesis of Compound Represented by Formula (I-12)]

10 parts of the compound represented by formula (I-4-a), 6.2 parts of carbonyldiimidazole and 50 parts of chloroform were mixed and stirred at 23° C. for 30 minutes. To the obtained mixed solution, 6.48 parts of the compound represented by the formula (I-12-b) was added, stirred at 60°C for 3 hours, and then cooled to 23°C. The obtained reactant was mixed with 50 parts of ion-exchanged water, stirred at 23° C. for 30 minutes, and separated to recover an organic layer. This washing operation was performed three times. After concentrating the obtained organic layer, the collected concentrated residue was applied to a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Ltd., developing solvent: chloroform/ethyl acetate=1/2). By extraction, 6.22 parts of the compound represented by the formula (I-12) was obtained.
MS (mass spectroscopy): 414.1 [M+H] ⁺

式（Ｉ－４－ａ）で表される化合物１０部、カルボニルジイミダゾール６．２部及びクロロホルム５０部を混合し、２３℃で３０分間攪拌した。得られた混合溶液に、式（Ｉ－２２－ｂ）で表される化合物１１．９３部を添加し、６０℃で３時間攪拌した後、２３℃まで冷却した。得られた反応物に、イオン交換水５０部を混合して２３℃で３０分間攪拌し、分液することにより有機層を回収した。この水洗の操作を３回行った。得られた有機層を濃縮した後、回収された濃縮残渣をカラム（シリカゲル６０Ｎ（球状、中性）１００－２１０μｍ；関東化学（株）製、展開溶媒：クロロホルム／酢酸エチル＝１／４）分取することにより、式（Ｉ－２２）で表される化合物５．６９部を得た。
ＭＳ（質量分析）：５５６．１ ［Ｍ＋Ｈ］^＋ Synthesis Example 6 [Synthesis of compound represented by formula (I-22)]

10 parts of the compound represented by formula (I-4-a), 6.2 parts of carbonyldiimidazole and 50 parts of chloroform were mixed and stirred at 23° C. for 30 minutes. To the obtained mixed solution, 11.93 parts of the compound represented by the formula (I-22-b) was added, stirred at 60°C for 3 hours, and then cooled to 23°C. The obtained reactant was mixed with 50 parts of ion-exchanged water, stirred at 23° C. for 30 minutes, and separated to recover an organic layer. This washing operation was performed three times. After concentrating the obtained organic layer, the collected concentrated residue was applied to a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Ltd., developing solvent: chloroform/ethyl acetate=1/4). By extraction, 5.69 parts of the compound represented by the formula (I-22) was obtained.
MS (mass spectroscopy): 556.1 [M+H] ⁺

Synthesis of Resin The compounds (monomers) used in synthesizing the resin are shown below.

Hereinafter, these monomers are referred to as "monomer (a1-1-1)" and the like according to their formula numbers.

Synthesis Example 7 [Synthesis of resin A1]
As monomers, monomer (a1-4-2), monomer (a1-1-3), monomer (a1-2-6), monomer (a3-1-1) and monomer (II-2-A-1-1 ), the molar ratio [monomer (a1-4-2): monomer (a1-1-3): monomer (a1-2-6): monomer (a3-1-1): monomer (II-2- A-1-1)] are mixed in a ratio of 32:25:35:5:3, and further, to this monomer mixture, 1.5 times the mass of methyl Isobutyl ketone was mixed in. To the resulting mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% with respect to the total number of moles of all monomers, and the mixture was heated at 85° C. for about 5 hours to polymerize. did Thereafter, an aqueous solution of p-toluenesulfonic acid was added to the polymerization reaction solution, stirred for 6 hours, and then separated. The collected organic layer is poured into a large amount of n-heptane to precipitate the resin, filtered and collected to obtain a resin A1 (copolymer) having a weight average molecular weight of about 8.0×10 ³ with a yield of 68. obtained in %. This resin A1 has the following structural units.

Synthesis Example 8 [Synthesis of resin A2]
As monomers, monomer (a1-4-2), monomer (a1-1-3), monomer (a1-2-6) and monomer (a3-1-1) are used, and the molar ratio [monomer (a1-4 -2): Monomer (a1-1-3): Monomer (a1-2-6): Monomer (a3-1-1)] are mixed so that the ratio is 35: 25: 35: 5, and the resin Resin A1 (copolymer) having a weight average molecular weight of about 8.0×10 ³ was obtained in a yield of 65% by the same method as A2. This resin A2 has the following structural units.

Synthesis Example 9 [Synthesis of resin A3]
As monomers, monomer (a1-4-2), monomer (a1-1-3) and monomer (a1-2-6) are used, and the molar ratio [monomer (a1-4-2):monomer (a1-1 -3): Monomer (a1-2-6)] are mixed at a ratio of 35:25:40, and the weight average molecular weight is about 7.6 × 10 ³ by the same method as resin A1. Resin A3 (copolymer) was obtained with a yield of 64%. This resin A3 has the following structural units.

Synthesis Example 10 [Synthesis of Resin A4]
As monomers, monomer (a2-2-1), monomer (a1-1-3), monomer (a1-2-6) and monomer (a3-1-1) are used, and the molar ratio [monomer (a1-4 -2): Monomer (a1-1-3): Monomer (a1-2-6): Monomer (a3-1-1)] are mixed in a ratio of 35:25:35:5, and , 1.5 times the mass of methyl isobutyl ketone with respect to the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% with respect to the total number of moles of all monomers, and the mixture was heated at 75°C for about 5 hours to polymerize. did The resulting reaction mixture was poured into a large amount of methanol/water mixed solvent to precipitate the resin, which was filtered. The resulting resin was added to a mixed solvent of methanol/water, repulp, and then subjected to a refining operation of filtering twice to give a resin A4 (copolymer) having a weight average molecular weight of about 8.1×10 ³ . Obtained with a yield of 61%. This resin A4 has the following structural units.

<Preparation of resist composition>
Each of the components shown below was mixed in parts by mass shown in Table 1, dissolved in a solvent, and filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

＜化合物（Ｉ）＞
Ｉ－１：（東京化成工業（株）製）

Ｉ－４：式（Ｉ－４）で表される塩
Ｉ－１０：式（Ｉ－１０）で表される塩
Ｉ－１１：式（Ｉ－１１）で表される塩
Ｉ－１２：式（Ｉ－１２）で表される塩
Ｉ－１３：式（Ｉ－１３）で表される塩
Ｉ－２２：式（Ｉ－２２）で表される塩
＜クエンチャー（Ｃ）＞
Ｃ１：特開２０１１－３９５０２号公報記載の方法で合成

ＣＸ１：（東京化成工業（株）製）

Ｄ１：（東京化成工業（株）製）

＜溶剤（Ｅ）＞
プロピレングリコールモノメチルエーテルアセテート ４００部
プロピレングリコールモノメチルエーテル １００部
γ－ブチロラクトン ５部 <Resin (A)>
A1 to A4: Resin A1 to Resin A4
<Acid generator (B)>
B1-25: a salt represented by the formula (B1-25); synthesized by the method described in JP-A-2011-126869

<Compound (I)>
I-1: (manufactured by Tokyo Chemical Industry Co., Ltd.)

I-4: salt represented by formula (I-4) I-10: salt represented by formula (I-10) I-11: salt represented by formula (I-11) I-12: formula Salt represented by (I-12) I-13: Salt represented by formula (I-13) I-22: Salt represented by formula (I-22) <Quencher (C)>
C1: synthesized by the method described in JP-A-2011-39502

CX1: (manufactured by Tokyo Chemical Industry Co., Ltd.)

D1: (manufactured by Tokyo Chemical Industry Co., Ltd.)

<Solvent (E)>
Propylene glycol monomethyl ether acetate 400 parts Propylene glycol monomethyl ether 100 parts γ-butyrolactone 5 parts

(Evaluation of resist composition by electron beam exposure)
A 6-inch silicon wafer was treated with hexamethyldisilazane at 90° C. for 60 seconds on a direct hotplate. This silicon wafer was spin-coated with the resist composition so that the film thickness of the composition layer was 0.04 μm. After that, it was pre-baked for 60 seconds on a direct hot plate at the temperature shown in the "PB" column of Table 1 to form a composition layer. A line-and-space pattern was directly drawn on the composition layer formed on the wafer using an electron beam lithography machine ("HL-800D 50 keV" manufactured by Hitachi, Ltd.) while changing the exposure dose stepwise. .
After exposure, post-exposure baking was performed for 60 seconds on a hot plate at the temperature shown in the "PEB" column of Table 1, and puddle development was performed for 60 seconds with a 2.38% by mass tetramethylammonium hydroxide aqueous solution. , a resist pattern was obtained.
The obtained resist pattern (line and space pattern) was observed with a scanning electron microscope, and the effective sensitivity was defined as the exposure dose at which the line width and space width of the 60 nm line and space pattern were 1:1.

Line Edge Roughness Evaluation (LER): Line edge roughness was obtained by measuring the unevenness amplitude of the side wall surface of the resist pattern manufactured at effective sensitivity with a scanning electron microscope. Table 2 shows the results.

The resist composition of the present invention has good line edge roughness and is useful for fine processing of semiconductors.

Claims (6)

A resist composition containing a non-salt compound represented by formula (I), a resin containing a structural unit having an acid-labile group, and an acid generator.

[in the formula (I),
R ¹ represents a hydrocarbon group having 1 to 24 carbon atoms optionally having a hydroxy group, a nitro group, a halogen atom, an alkoxy group having 1 to 12 carbon atoms, or a carboxyl group, and is included in the hydrocarbon group; A methylene group may be substituted with an oxygen atom or a carbonyl group.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
Ar represents an aromatic hydrocarbon group having 6 to 24 carbon atoms which may have a substituent. ] A resist composition comprising a compound represented by formula (I'), a resin containing a structural unit having an acid-labile group, and an acid generator.

[in the formula (I′),
R ¹ represents a hydrocarbon group having 1 to 24 carbon atoms optionally having a hydroxy group, a nitro group, a halogen atom, an alkoxy group having 1 to 12 carbon atoms, or a carboxyl group, and is included in the hydrocarbon group; A methylene group may be substituted with an oxygen atom or a carbonyl group.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
Ar' represents an aromatic hydrocarbon group having 6 to 24 carbon atoms which may have a hydroxyl group, a nitro group, a halogen atom, a cyano group, an alkoxy group having 1 to 12 carbon atoms or a carboxyl group. ] R ¹ is an optionally substituted aromatic hydrocarbon group having 6 to 24 carbon atoms or R ³ —(O) _n —CO—* (in the formula, n represents 0 or 1; * is represents the bonding position with N. R ³ represents an optionally substituted hydrocarbon group having 1 to 22 carbon atoms, and the methylene group contained in the hydrocarbon group is an oxygen atom or a carbonyl group. 3. The resist composition according to claim 1, which is a group represented by (which may be substituted). 4. The resist composition according to any one of claims 1 to 3, wherein ^R2 is a hydrogen atom. 5. The resist composition according to any one of claims 1 to 4, further comprising a salt that generates an acid weaker in acidity than the acid generated from the acid generator. (1) a step of applying the resist composition according to any one of claims 1 to 5 onto a substrate;
(2) a step of drying the applied composition to form a composition layer;
(3) exposing the composition layer;
(4) heating the composition layer after exposure; and (5) developing the composition layer after heating;
A method of manufacturing a resist pattern comprising: