JP6569357B2 - Resist composition - Google Patents

Description

  The present invention relates to a resist composition.

Patent Document 1 describes a resist composition containing a resin composed of the following three structural units and an acid generator represented by the following formula (B1-6).

JP 2007-224008 A

  The resist pattern formed from the above resist composition may not always be satisfactory in terms of pattern shape and mask error factor (MEF).

［式（ＩＩ）中、
Ｒ^２は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表し、Ｘ^１は、単結合、−ＣＯ−Ｏ−＊又は−ＣＯ−ＮＲ^４−＊を表し、＊は−Ａｒとの結合手を表し、Ｒ^４は、水素原子又は炭素数１〜４のアルキル基を表し、Ａｒは、ヒドロキシ基及びカルボキシル基からなる群から選ばれる１以上の基を有していてもよい炭素数６〜２０の芳香族炭化水素基を表す。］
［２］Ｘ¹が、単結合である［１］記載のレジスト組成物。
［３］Ａｒが、１以上のヒドロキシ基を有していてもよい炭素数６〜２０の芳香族炭化水素基である［１］又は［２］に記載のレジスト組成物。
［４］Ａｒが、フェニル基である［１］〜［３］のいずれかに記載のレジスト組成物。
［５］フッ素原子を有し、かつ、酸不安定基を有する構造単位を含まない樹脂（Ａ２）をさらに含有する［１］〜［４］のいずれかに記載のレジスト組成物。
［６］３〜１８個のフッ素原子を有するアニオンが、環状構造を備えるアニオンである［１］〜［５］のいずれかに記載のレジスト組成物。 The present invention includes the following inventions.
[1] A resin (A1) containing a structural unit represented by formula (II) and a structural unit having an acid labile group, and an acid generator (Ba) containing an anion having 3 to 18 fluorine atoms Resist composition to contain.

[In the formula (II),
R ² represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom, and X ¹ represents a single bond, —CO—O— * or —CO—NR ⁴ — *. * Represents a bond with -Ar, R ⁴ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and Ar represents one or more groups selected from the group consisting of a hydroxy group and a carboxyl group. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have ]
[2] The resist composition according to [1], wherein X ¹ is a single bond.
[3] The resist composition according to [1] or [2], wherein Ar is an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have one or more hydroxy groups.
[4] The resist composition according to any one of [1] to [3], wherein Ar is a phenyl group.
[5] The resist composition according to any one of [1] to [4], further containing a resin (A2) having a fluorine atom and not containing a structural unit having an acid labile group.
[6] The resist composition according to any one of [1] to [5], wherein the anion having 3 to 18 fluorine atoms is an anion having a cyclic structure.

  According to the resist composition of the present invention, a resist pattern having a good pattern shape and mask error factor (MEF) can be produced.

The schematic diagram of the cross-sectional shape of a contact hole pattern is represented. FIG. 1A shows a cross section with a top shape close to a rectangle, and FIG. 1B shows a cross section with a round top shape.

  In this specification, “(meth) acrylate” means “at least one of acrylate and methacrylate”, and the notation such as “(meth) acrylic acid” and “(meth) acryloyl” has the same meaning.

<Resist composition>
The resist composition of the present invention contains a resin (A1) and an acid generator (Ba), and may contain a resin (A2).

<Resin (A1)>
The resin (A1) includes a structural unit represented by the formula (II) (hereinafter sometimes referred to as “structural unit (II)”) and a structural unit having an acid labile group (hereinafter referred to as “structural unit (a1)”). And so on.) The resin (A1) may contain a structural unit having no acid labile group (hereinafter, sometimes referred to as “structural unit (s)”). The “acid-labile group” of the structural unit is a group having a leaving group, and the leaving group is eliminated by contact with an acid to have a hydrophilic group (for example, a hydroxy group or a carboxyl group). A group that is converted to a structural unit.

［式（ＩＩ）中、
Ｒ^２は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表し、Ｘ^１は、単結合、−ＣＯ−Ｏ−＊又は−ＣＯ−ＮＲ^４−＊を表し、＊は−Ａｒとの結合手を表し、Ｒ^４は、水素原子又は炭素数１〜４のアルキル基を表し、Ａｒは、ヒドロキシ基及びカルボキシル基からなる群から選ばれる１以上の基を有していてもよい炭素数６〜２０の芳香族炭化水素基を表す。］ <Structural unit (II)>
The structural unit (II) is represented by the following formula (II).

[In the formula (II),
R ² represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom, and X ¹ represents a single bond, —CO—O— * or —CO—NR ⁴ — *. * Represents a bond with -Ar, R ⁴ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and Ar represents one or more groups selected from the group consisting of a hydroxy group and a carboxyl group. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have ]

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n- An unsubstituted alkyl group having 1 to 6 carbon atoms such as a pentyl group and an n-hexyl group, and a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro-sec-butyl group, Examples thereof include C1-C6 haloalkyl groups such as perfluoro-tert-butyl group, perfluoropentyl group, perfluorohexyl group, trichloromethyl group, tribromomethyl group, triiodomethyl group, preferably C1-C4. An unsubstituted alkyl group, more preferably a methyl group and an ethyl group.
R ² is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and more preferably a hydrogen atom or a methyl group.

Examples of the alkyl group having 1 to 4 carbon atoms represented by R ⁴ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, and a tert-butyl group.

X ¹ is preferably a single bond or —CO—O— *, and more preferably a single bond.

Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms include phenyl group, o-methylphenyl group, m-methylphenyl group, p-methylphenyl group, p-ethylphenyl group, p-tert-butylphenyl group, 1 -A naphthyl group, 2-naphthyl group, 1-anthryl group, 9-anthryl group, 1-phenanthryl group and 2-phenanthryl group are mentioned. Such an aromatic hydrocarbon group may have one or more groups selected from the group consisting of a hydroxy group and a carboxyl group, and may have 6 to 20 carbon atoms that may have one or more hydroxy groups. A group hydrocarbon group is preferred. Examples of the aromatic hydrocarbon group having one or more groups selected from the group consisting of a hydroxy group and a carboxyl group include 4-hydroxyphenyl group, 4-carboxyphenyl group, 4-hydroxy-1-naphthyl group, and 10-hydroxy- A 9-anthryl group may be mentioned.
Ar is preferably an aromatic hydrocarbon group having 6 to 20 carbon atoms, more preferably an aromatic hydrocarbon group having 6 to 14 carbon atoms, and still more preferably a phenyl group.

Specific examples of the structural unit (II) include structural units represented by the following formulas (II-1) to (II-12), and structural units represented by the following formulas (II-1) to (II-9). In the structural unit in which the hydrogen atom corresponding to R ² is replaced with a methyl group, and the structural unit represented by the following formulas (II-10) to (II-12), the methyl group corresponding to R ² is Examples include structural units replaced by hydrogen atoms.

  Especially, the structural unit represented by Formula (II-1)-Formula (II-6) is preferable.

［式（ＩＩ’）中、Ｒ^２、Ａｒ及びＸ¹は上記と同じ意味を表す。］ The structural unit (II) is derived from a monomer represented by the formula (II ′) (hereinafter sometimes referred to as “monomer (II ′)”).

[In the formula (II ′), R ² , Ar and X ¹ represent the same meaning as described above. ]

As the monomer (II ′), monomers represented by the following formulas (II′-1) to (II′-12), monomers represented by the following formulas (II′-1) to (II′-9) A monomer in which a hydrogen atom corresponding to R ² is replaced with a methyl group, and a methyl group corresponding to R ² in the monomers represented by the following formulas (II′-10) to (II′-12) are hydrogen atoms. Examples include substituted monomers.

  Compound (II ') is easily available from the market.

  The content of the structural unit (II) in the resin (A1) is preferably 0.5 to 15 mol%, more preferably 0.5 to 10 mol%, based on all the structural units of the resin (A1). More preferably, it is 1-8 mol%, Most preferably, it is 1-6 mol%.

<Structural unit (a1)>
The content of the structural unit (a1) in the resin (A1) is preferably from 10 to 99.5 mol%, more preferably from 20 to 99.5 mol%, based on all the structural units of the resin (A1). Preferably it is 30-99 mol%, Most preferably, it is 50-99 mol%.

［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、又は、Ｒ^a1及びＲ^a2は互いに結合して炭素数２〜２０の２価の炭化水素基を形成し、Ｒ^a3は、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。
ｎａは、０又は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、又は、Ｒ^a1’は、水素原子又は炭素数１〜１２の炭化水素基を表し、Ｒ^a2’及びＲ^a3’は互いに結合して炭素数２〜２０の２価の炭化水素基を形成し、該炭化水素基及び該２価の炭化水素基に含まれる−ＣＨ_２−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。
＊は結合手を表す。］ The structural unit (a1) is derived from a monomer having an acid labile group (hereinafter sometimes referred to as “monomer (a1)”).
The monomer (a1) is preferably a monomer having an acid labile group and an ethylenically unsaturated bond, and more preferably a (meth) acrylic monomer having an acid labile group.
In the resin (A1), a group represented by the following formula (1) and / or a group represented by the following formula (2) is preferable.

[In Formula (1), R ^<a1 > -R < ^a3 > respectively independently represents a C1-C8 alkyl group, a C3-C20 alicyclic hydrocarbon group, or the group which combined these, or R ^a1 and R ^a2 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms, and R ^a3 is an alkyl group having 1 to 8 carbon atoms or an alicyclic carbon atom having 3 to 20 carbon atoms. A hydrogen group or a combination thereof is represented.
na represents 0 or 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. R ^{a1 ′} represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R ^{a2 ′} and R ^{a3 ′} are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms. And —CH ₂ — contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by —O— or —S—.
X represents an oxygen atom or a sulfur atom.
* 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、メチルシクロヘキシル基、ジメチルシクロへキシル基、メチルノルボルニル基等が挙げられる。 ^Examples of the alkyl group represented by R ^{a1 to} R ^a3 include a methyl group, an ethyl group, a propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, and an n-octyl group.
The alicyclic hydrocarbon group for R ^{a1 to} R ^a3 may be monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents a bond). The alicyclic hydrocarbon group of R ^{a1 to} R ^a3 preferably has 3 to 16 carbon atoms.

Examples of the group combining an alkyl group and an alicyclic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, and a methylnorbornyl group.

In the case where R ^a1 and R ^a2 are bonded to each other to form a divalent hydrocarbon group, -C (R ^a1 ) (R ^a2 ) (R ^a3 ) includes the following groups, and * represents —O— Represents a bond with The carbon number of the divalent hydrocarbon group is preferably 3-12.

Examples of the group represented by the formula (1) include a 1,1-dialkylalkoxycarbonyl group (a group in which R ^{a1 to} R ^a3 are alkyl groups in the formula (1), preferably a tert-butoxycarbonyl group), 2- An alkyladamantan-2-yloxycarbonyl group (in the formula (1), R ^a1 and R ^a2 are bonded to each other, and together with the carbon atom to which they are bonded form an adamantyl group, R ^a3 is an alkyl group) Group) and 1- (adamantan-1-yl) -1-alkylalkoxycarbonyl group (in the formula (1), R ^a1 and R ^a2 are alkyl groups, and R ^a3 is an adamantyl group). .

Examples of the hydrocarbon group of R ^{a1 ′ to} R ^{a3 ′} include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these.
Examples of the alkyl group and alicyclic hydrocarbon group include the same groups as described above.
Aromatic hydrocarbon groups include phenyl, naphthyl, anthryl, p-methylphenyl, p-tert-butylphenyl, p-adamantylphenyl, xylyl, cumyl, mesityl, biphenyl, phenanthryl Groups, aryl groups such as 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl, and the like.
Examples of the divalent hydrocarbon group formed by combining R ^{a2 ′} and R ^{a3 ′} include groups in which one hydrogen atom has been removed from the hydrocarbon groups of R ^{a1 ′ to} R ^{a3 ′} .
At least one of R ^{a1 ′} and R ^{a2 ′} is preferably a hydrogen atom.

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

  Of the (meth) acrylic monomers having an acid labile group, (meth) acrylic monomers having an alicyclic hydrocarbon group having 5 to 20 carbon atoms are preferred. From the resist composition containing the resin (A1) having a structural unit derived from the monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group, a resist pattern with improved resolution can be formed.

  Preferable examples of the structural unit derived from the (meth) acrylic monomer having a group represented by the formula (1) include a structural unit represented by the formula (a1-0) and a formula (a1-1). And structural units represented by formula (a1-2). These may be used alone or in combination of two or more. In this specification, the structural unit represented by formula (a1-0), the structural unit represented by formula (a1-1), and the structural unit represented by formula (a1-2) are each represented by structural unit (a1). -0), structural unit (a1-1), and structural unit (a1-2) in some cases, a monomer for deriving structural unit (a1-0), a monomer for deriving structural unit (a1-1), and a structural unit The monomer for deriving (a1-2) may be referred to as monomer (a1-0), monomer (a1-1), and monomer (a1-2), respectively.

［式（ａ１−０）中、
Ｌ^a01は、酸素原子又は＊−Ｏ−（ＣＨ₂）_k01−ＣＯ−Ｏ−を表し、ｋ０１は１〜７の整数を表し、＊はカルボニル基との結合手を表す。
Ｒ^a01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。］

[In the formula (a1-0),
L ^a01 represents an oxygen atom or * —O— (CH ₂ ) _k01 —CO—O—, k01 represents an integer of 1 to 7, and * represents a bond to a carbonyl group.
R ^a01 independently represents 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. ]

［式（ａ１−１）及び式（ａ１−２）中、
Ｌ^a1及びＬ^a2は、それぞれ独立に、−Ｏ−又は＊−Ｏ−（ＣＨ₂）_k1−ＣＯ−Ｏ−を表し、ｋ１は１〜７の整数を表し、＊は−ＣＯ−との結合手を表す。
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^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み合わせることにより形成される基を表す。
ｍ１は０〜１４の整数を表す。
ｎ１は０〜１０の整数を表す。
ｎ１’は０〜３の整数を表す。］

[In Formula (a1-1) and Formula (a1-2),
L ^a1 and L ^a2 each independently represent —O— or * —O— (CH ₂ ) _k1 —CO—O—, k1 represents an integer of 1 to 7, and * represents a bond to —CO—. Represents a hand.
R ^a4 and R ^a5 each independently represent a hydrogen atom or a methyl group.
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 the integer of 0-14.
n1 represents an integer of 0 to 10.
n1 ′ represents an integer of 0 to 3. ]

L ^a02 is preferably an oxygen atom or * —O— (CH ₂ ) _k01 —CO—O—, and more preferably an oxygen atom. k01 is preferably an integer of 1 to 4, more preferably 1.
Examples of the alkyl group of R ^a02 , R ^a03, and R ^a04 , the alicyclic hydrocarbon group, and a group obtained by combining these include the same groups as those described for R ^{a1 to} R ^a3 in formula (1).
The alkyl group of R ^a02 , R ^a03 and R ^a04 is preferably an alkyl group having 6 or less carbon atoms.
The alicyclic hydrocarbon group of R ^a02 , R ^a03 and R ^a04 is preferably an alicyclic hydrocarbon group having 8 or less carbon atoms, more preferably an alicyclic hydrocarbon group having 6 or less carbon atoms.
The group combining the alkyl group and the alicyclic hydrocarbon group preferably has a total carbon number of 18 or less, combining the alkyl group and the alicyclic hydrocarbon group. Examples of such a group include a methylcyclohexyl group, a dimethylcyclohexyl group, and a methylnorbornyl group.
R ^a02 and R ^a03 are preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group.
R ^a04 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 12 carbon atoms, and more preferably a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group.

L ^a1 and L ^a2 are preferably —O— or * —O— (CH ₂ ) _{k1 ′} —CO—O—, more preferably —O—. k1 ′ is an integer of 1 to 4, preferably 1.
R ^a4 and R ^a5 are preferably methyl groups.
^Examples of the alkyl group for R ^a6 and R ^a7 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, Examples include n-heptyl group, 2-ethylhexyl group, n-octyl group and the like.
The alicyclic hydrocarbon group for R ^a6 and R ^a7 may be either monocyclic or polycyclic, and the monocyclic alicyclic hydrocarbon group includes a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, Examples thereof include cycloalkyl groups such as a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cycloheptyl group, and a cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1- (adamantan-1-yl) alkane-1-yl group, norbornyl group, Examples thereof include a methylnorbornyl group and an isobornyl group.
Examples of the group formed by combining the alkyl group of R ^a6 and R ^a7 and the alicyclic hydrocarbon group include an aralkyl group, and examples thereof include a benzyl group and a phenethyl group.
The alkyl group of R ^a6 and R ^a7 is preferably an alkyl group having 6 or less carbon atoms.
The alicyclic hydrocarbon group of R ^a6 and R ^a7 is preferably an alicyclic hydrocarbon group having 8 or less carbon atoms, more preferably an alicyclic hydrocarbon group having 6 or less carbon atoms.
m1 is preferably an integer of 0 to 3, more preferably 0 or 1.
n1 is preferably an integer of 0 to 3, more preferably 0 or 1.
n1 ′ is preferably 0 or 1.

As the structural unit (a1-0), a structural unit represented by the formula (a1-0-1) to the formula (a1-1-12) and a methyl group corresponding to R ^a01 in these structural units are hydrogen atoms. The substituted structural unit is mentioned, Preferably it is a structural unit represented by either of Formula (a1-0-1)-Formula (a1-1-10).

As a monomer (a1-1), the monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned. Among these, monomers represented by the following formulas (a1-1-1) to (a1-1-8) are preferable, and monomers represented by the formulas (a1-1-1) to (a1-1-4) are preferable. Is more preferable.

As the monomer (a1-2), 1-methylcyclopentan-1-yl (meth) acrylate, 1-ethylcyclopentan-1-yl (meth) acrylate, 1-methylcyclohexane-1-yl (meth) acrylate, 1-ethylcyclohexane-1-yl (meth) acrylate, 1-ethylcycloheptan-1-yl (meth) acrylate, 1-ethylcyclooctane-1-yl (meth) acrylate, 1-isopropylcyclopentan-1-yl (Meth) acrylate and 1-isopropylcyclohexane-1-yl (meth) acrylate are mentioned. Among these, monomers represented by the following formulas (a1-2-1) to (a1-2-12) are preferable, and the formulas (a1-2-3), (a1-2-4), and (a1- 2-9) and a monomer represented by formula (a1-2-10) are more preferred, and a monomer represented by formula (a1-2-3) and formula (a1-2-9) is more preferred.

  When the resin (A1) includes the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is the total structure of the resin (A1). It is 10-95 mol% normally with respect to a unit, Preferably it is 15-90 mol%, More preferably, it is 20-85 mol%.

式（ａ１−３）中、
Ｒ^a9は、ヒドロキシ基を有していてもよい炭素数１〜３の脂肪族炭化水素基、カルボキシ基、シアノ基、水素原子又は−ＣＯＯＲ^a13を表す。
Ｒ^a13は、炭素数１〜８の脂肪族炭化水素基、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ることにより形成される基を表し、該脂肪族炭化水素基及び該脂環式炭化水素基に含まれる水素原子は、ヒドロキシ基で置換されていてもよく、該脂肪族炭化水素基及び該脂環式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い。
Ｒ^a10、Ｒ^a11及びＲ^a12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ることにより形成される基を表すか、又は、Ｒ^a12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ることにより形成される基を表し、Ｒ^a10及びＲ^a11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２〜２０の２価の炭化水素基を形成する。 Furthermore, examples of the structural unit (a1) having a group represented by the formula (1) include a structural unit represented by the formula (a1-3). The structural unit represented by the formula (a1-3) may be referred to as a structural unit (a1-3). Moreover, the monomer which derives the structural unit (a1-3) may be referred to as a monomer (a1-3).

In formula (a1-3),
R ^a9 represents an aliphatic hydrocarbon group having 1 to 3 carbon atoms which may have a hydroxy group, a carboxy group, a cyano group, a hydrogen atom, or —COOR ^a13 .
R ^a13 represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a group formed by a combination thereof, the aliphatic hydrocarbon group and the The hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a hydroxy group, and —CH ₂ — contained in the aliphatic hydrocarbon group and the alicyclic hydrocarbon group is —O— or -CO- may be substituted.
R ^a10 , R ^a11 and R ^a12 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 formed by combining these, or , R ^a12 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms or a group formed by combining these, R ^a10 and R ^a11 are Combined to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the carbon atom to which they are bonded.

Here, -COOR ^a13 includes a group in which a carbonyl group is bonded to an alkoxy group such as a methoxycarbonyl group or an ethoxycarbonyl group.

Examples of the aliphatic hydrocarbon group which may have a hydroxy group of R ^a9 include a methyl group, an ethyl group, an n-propyl group, a hydroxymethyl group and a 2-hydroxyethyl group.
^Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms represented by R ^a13 include a methyl group, an ethyl group, and an n-propyl group.
^Examples of the alicyclic hydrocarbon group having 3 to 20 carbon atoms represented by R ^a13 include a cyclopentyl group, a cyclopropyl group, an adamantyl group, an adamantylmethyl group, a 1-adamantyl-1-methylethyl group, and 2-oxo-oxolane-3- Yl group and 2-oxo-oxolan-4-yl group.
^Examples of the alkyl group represented by R ^{a10 to} R ^a12 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, Examples include n-heptyl group, 2-ethylhexyl group and n-octyl group.
The alicyclic hydrocarbon group of R ^{a10 to} R ^a12 may be monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, Examples thereof include cycloalkyl groups such as a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cycloheptyl group, and a cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1- (adamantan-1-yl) alkane-1-yl group, norbornyl group, A methyl norbornyl group and an isobornyl group are mentioned.
-C (R ^a10 ) (R ^a11 ) (R ^a12 ) in the case where R ^a10 and R ^a11 are bonded to each other to form a divalent hydrocarbon group together with the carbon atom to which they are bonded, Groups are preferred.

  Specific examples of the monomer (a1-3) include 5-norbornene-2-carboxylic acid-tert-butyl, 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, and 5-norbornene-2-carboxylic acid. Acid 1-methylcyclohexyl, 5-norbornene-2-carboxylic acid 2-methyl-2-adamantyl, 5-norbornene-2-carboxylic acid 2-ethyl-2-adamantyl, 5-norbornene-2-carboxylic acid 1- (4 -Methylcyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1- (4-hydroxycyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1-methyl-1- (4-oxo (Cyclohexyl) ethyl and 1- (1-adamantyl) -1-methyl 5-norbornene-2-carboxylate Chill, and the like.

  Since the resin (A1) containing the structural unit (a1-3) contains a three-dimensionally bulky structural unit, the resist composition containing such a resin (A1) can be resisted at a higher resolution. A pattern can be obtained. Further, since a rigid norbornane ring is introduced into the main chain, the resulting resist pattern tends to be excellent in dry etching resistance.

  When the resin (A1) includes the structural unit (a1-3), the content thereof is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, based on all the structural units of the resin (A1). 20-85 mol% is more preferable.

［式（ａ１−４）中、
Ｒ^a32は、水素原子、ハロゲン原子、又は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。
Ｒ^a33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。
ｌａは０〜４の整数を表す。ｌａが２以上である場合、複数のＲ^a33は互いに同一であっても異なってもよい。
Ｒ^a34及びＲ^a35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^a36は、炭素数１〜２０の炭化水素基を表すか、又は、Ｒ^a34は、水素原子又は炭素数１〜１２の炭化水素基を表し、Ｒ^a35及びＲ^a36は互いに結合して炭素数２〜２０の２価の炭化水素基を形成し、該炭化水素基及び該２価の炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−Ｓ−で置き換わってもよい。］ As the structural unit (a1) having a group represented by the group (2), a structural unit represented by the formula (a1-4) (hereinafter sometimes referred to as “structural unit (a1-4)”). Can be mentioned.

[In the formula (a1-4),
R ^a32 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
R ^a33 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.
la represents an integer of 0 to 4. When la is 2 or more, the plurality of R ^a33 may be the same as or different from each other.
R ^a34 and R ^a35 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, or R ^a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or, R ^a34 is a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R ^a35 and R ^a36 are bonded together to form a divalent hydrocarbon group having 2 to 20 carbon atoms with each other, the hydrocarbon group and the divalent hydrocarbon —CH ₂ — contained in the group may be replaced by —O— or —S—. ]

^Examples of the alkyl group for R ^a32 and R ^a33 include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group, and an alkyl group having 1 to 4 carbon atoms. Group is preferred, a methyl group or ethyl group is more preferred, and a methyl group is more preferred.
Examples of the halogen atom for R ^a32 and R ^a33 include a fluorine atom, a chlorine atom and a bromine atom.
The R ^a34 and R ^a35, include the same groups as R ¹⁴ and R ¹⁵ of formula (2).
The R ^a36, include groups formed by combining an alkyl group having 1 to 18 carbon atoms, alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms and these It is done.

In formula (a1-4), R ^a32 is preferably a hydrogen atom.
R ^a33 is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and further preferably a methoxy group.
la is preferably 0 or 1, more preferably 0.
R ^a34 is preferably a hydrogen atom.
R ^a35 is preferably a hydrocarbon group having 1 to 12 carbon atoms, more preferably a methyl group or an ethyl group.
The hydrocarbon group for R ^a36 is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof. It is a group to be formed, more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic aliphatic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. The alkyl group and the alicyclic hydrocarbon group in R ^a36 are preferably unsubstituted. When the aromatic hydrocarbon group in R ^a36 has a substituent, the substituent is preferably an aryloxy group having 6 to 10 carbon atoms.

Examples of the monomer that leads to the structural unit (a1-4) include monomers described in JP 2010-204646 A. Especially, the monomer represented by Formula (a1-4-1)-Formula (a1-4-7) is preferable, and the monomer represented by Formula (a1-4-1)-Formula (a1-4-5) is preferable. More preferred.

  When resin (A1) has a structural unit (a1-4), the content rate is preferable with respect to all the structural units of resin (A1), and 10-95 mol% is more preferable, and 15-90 mol% is more preferable. 20 to 85 mol% is more preferable.

式（ａ１−５）中、
Ｒ^a8は、ハロゲン原子を有してもよい炭素数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の整数を表す。
ｓ１’は、０〜３の整数を表す。 Examples of the structural unit having an acid labile group include a structural unit represented by the formula (a1-5) (hereinafter sometimes referred to as “structural unit (a1-5)”).

In formula (a1-5),
R ^a8 represents a C 1-6 alkyl group optionally having 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 to L ⁵¹ .
L ⁵¹ , L ⁵² , L ⁵³ and L ⁵⁴ each independently represent —O— or —S—.
s1 represents an integer of 1 to 3.
s1 ′ represents an integer of 0 to 3.

In formula (a1-5), R ^a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group.
L ⁵¹ is preferably —O—.
It is preferable that one of L ⁵² and L ⁵³ is —O— and the other is —S—.
s1 is preferably 1.
s1 ′ is preferably an integer of 0 to 2.
Z ^a1 is preferably a single bond or * —CH ₂ —CO—O—.

Examples of the monomer for deriving the structural unit (a1-5) include monomers described in JP 2010-61117 A. Among these, monomers represented by formula (a1-5-1) to formula (a1-5-4) are preferable, and monomers represented by formula (a1-5-1) and formula (a1-5-2) are preferable. More preferred.

  When the resin (A1) has the structural unit (a1-5), the content is preferably from 1 to 50 mol%, more preferably from 3 to 45 mol%, based on all the structural units of the resin (A1). 5 to 40 mol% is more preferable.

The structural unit (a) having an acid labile group in the resin (A1) includes the structural unit (a1-0), the structural unit (a1-1), the structural unit (a1-2), and the structural unit (a1-5). ) Is preferably at least one selected from the group consisting of, and more preferably at least two, a combination of structural unit (a1-1) and structural unit (a1-2), structural unit (a1-1) and structural unit ( a1-5), a structural unit (a1-1) and a structural unit (a1-0), a structural unit (a1-2) and a structural unit (a1-0), and a structural unit (a1-5) And a combination of the structural unit (a1-0), a structural unit (a1-0), a combination of the structural unit (a1-1) and the structural unit (a1-2), a structural unit (a1-0), and a structural unit (a1- 1) and structural unit (a1-5 More preferably a combination of a combination of structural units (a1-1) and the structural unit (a1-2), more preferably a combination of structural units (a1-1) and the structural unit (a1-5).

<Structural unit without acid labile group>
The structural unit (s) is derived from a monomer having no acid labile group (hereinafter sometimes referred to as “monomer (s)”). Examples of the monomer (s) include monomers having no acid labile group, which are well known in the resist field. Preferred structural units are structural units having a hydroxy group or a lactone ring and having no acid labile group. A structure having a hydroxy group and having no acid labile group (hereinafter sometimes referred to as “structural unit (a2)”) and / or a lactone ring and having no acid labile group From a resist composition containing a resin having a unit (hereinafter sometimes referred to as “structural unit (a3)”), a resist pattern with improved resolution and adhesion to the substrate can be formed.

<Structural unit (a2)>
The hydroxy group contained in the structural unit (a2) is preferably an alcoholic hydroxy group. Examples of the structural unit (a2) having an alcoholic hydroxy group include a structural unit represented by the formula (a2-1) (hereinafter sometimes referred to as “structural unit (a2-1)”).

［式（ａ２−１）中、
Ｌ^ａ３は、−Ｏ−又は^＊−Ｏ−（ＣＨ_２）_ｋ２−ＣＯ−Ｏ−を表し、
ｋ２は１〜７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の整数を表す。］

[In the formula (a2-1),
L ^a3 represents —O— or ^* —O— (CH ₂ ) _k2 —CO—O—,
k2 represents an integer of 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 an integer of 0 to 10. ]

In formula (a2-1), L ^a3 is preferably —O—, —O— (CH ₂ ) _f1 —CO—O— (wherein 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 an integer of 0 to 3, more preferably 0 or 1.

  Examples of the monomer that derives the structural unit (a2-1) include monomers described in JP 2010-204646 A. A monomer represented by any one of formula (a2-1-1) to formula (a2-1-6) is preferable, and represented by any one of formula (a2-1-1) to formula (a2-1-4). The monomer represented by Formula (a2-1-1) or Formula (a2-1-3) is more preferable.

  Resin (A1) may contain 1 type of structural units (a2), and may also contain 2 or more types of structural units (a2).

Examples of the structural unit (a2-1) having an alcoholic hydroxy group include the following structural units.

Especially, the structural unit represented by Formula (a2-1-1)-Formula (a2-1-4) is preferable, and it represents with Formula (a2-1-1) and Formula (a2-1-3). A structural unit is more preferable.
Examples of the monomer for deriving the structural unit (a2) having an alcoholic hydroxy group include monomers described in JP-A No. 2010-204646.

  When resin (A1) contains a structural unit (a2-1), the content rate is 1-45 mol% normally with respect to all the structural units of resin (A1), Preferably it is 1-40 mol%. More preferably, it is 1-35 mol%, More preferably, it is 2-20 mol%.

［式（ａ３−１）中、
Ｌ^ａ４は、−Ｏ−又は^＊−Ｏ−（ＣＨ_２）_ｋ３−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）で表される基を表す。＊はカルボニル基との結合手を表す。
Ｒ^ａ１８は、水素原子又はメチル基を表す。
Ｒ^ａ２１は炭素数１〜４の脂肪族炭化水素基を表す。
ｐ１は０〜５の整数を表す。ｐ１が２以上のとき、複数のＲ^ａ２１は互いに同一であっても異なってもよい。
式（ａ３−２）中、
Ｌ^ａ５は、−Ｏ−又は^＊−Ｏ−（ＣＨ_２）_ｋ３−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）で表される基を表す。＊はカルボニル基との結合手を表す。
Ｒ^ａ１９は、水素原子又はメチル基を表す。
Ｒ^ａ２２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。
ｑ１は、０〜３の整数を表す。ｑ１が２以上のとき、複数のＲ^ａ２２は互いに同一であっても異なってもよい。
式（ａ３−３）中、
Ｌ^ａ６は、−Ｏ−又は^＊−Ｏ−（ＣＨ_２）_ｋ３−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）で表される基を表す。＊はカルボニル基との結合手を表す。
Ｒ^ａ２０は、水素原子又はメチル基を表す。
Ｒ^ａ２３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。
ｒ１は、０〜３の整数を表す。ｒ１が２以上のとき、複数のＲ^ａ２３は互いに同一であっても異なってもよい。］ <Structural unit (a3)>
The lactone ring of the structural unit (a3) may be a monocycle such as a β-propiolactone ring, γ-butyrolactone ring, or δ-valerolactone ring, or a condensed ring of a monocyclic lactone ring and another ring. But you can. Preferably, a γ-butyrolactone ring or a bridged ring containing a γ-butyrolactone ring structure is used. The structural unit (a3) may contain two or more kinds. The structural unit (a3) is preferably a structural unit represented by the formula (a3-1), the formula (a3-2), or the formula (a3-3). These 1 type may be contained independently and 2 or more types may be contained.

[In the formula (a3-1),
L ^a4 represents a group represented by —O— or ^* —O— (CH ₂ ) _k3 —CO—O— (k3 represents an integer of 1 to 7). * Represents a bond with a carbonyl group.
R ^a18 represents a hydrogen atom or a methyl group.
R ^a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
p1 represents an integer of 0 to 5. When p1 is 2 or more, the plurality of R ^a21 may be the same as or different from each other.
In formula (a3-2),
L ^a5 represents a group represented by —O— or ^* —O— (CH ₂ ) _k3 —CO—O— (k3 represents an integer of 1 to 7). * Represents a bond with a carbonyl group.
R ^a19 represents a hydrogen atom or a methyl group.
R ^a22 represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
q1 represents an integer of 0 to 3. When q1 is 2 or more, the plurality of R ^a22 may be the same as or different from each other.
In formula (a3-3),
L ^a6 represents a group represented by —O— or ^* —O— (CH ₂ ) _k3 —CO—O— (k3 represents an integer of 1 to 7). * Represents a bond with a carbonyl group.
R ^a20 represents a hydrogen atom or a methyl group.
R ^a23 represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
r1 represents an integer of 0 to 3. When r1 is 2 or more, the plurality of R ^a23 may be the same as or different from each other. ]

In formula (a3-1) to formula (a3-3), L ^{a4 to} L ^a6 are each independently preferably —O— or k— is an integer of 1 to 4 * —O— (CH ₂ ). a group represented by _{k 3} —CO—O—, more preferably —O— and * —O—CH ₂ —CO—O—, and still 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 and r1 are each independently preferably an integer of 0 to 2, more preferably 0 or 1.

  As monomers for deriving the structural unit (a3), monomers described in JP 2010-204646 A, monomers described in JP 2000-122294 A, monomers described in JP 2012-41274 A are listed. Can be mentioned. As the structural unit (a3), the formula (a3-1-1) to the formula (a3-1-6), the formula (a3-2-1) to the formula (a3-2-4), and the formula (a3-3) 1) to a structural unit represented by any one of the formula (a3-3-4) and the formula (a3-4-1) to the formula (a3-4-6), the formula (a3-1-1), The structural unit represented by any one of the formula (a3-1-2) and the formula (a3-2-3) to the formula (a3-2-4) is more preferable, and the formula (a3-1-1) or the formula ( The structural unit represented by a3-2-3) is more preferable.

  When the resin (A1) contains the structural unit (a3), the content is usually 5 to 70 mol%, preferably 10 to 65 mol%, based on all the structural units of the resin (A1). More preferably, it is 10-60 mol%.

<Other structural units (t)>
As the structural unit (t), in addition to the structural unit (a2) and the structural unit (a3), a structural unit having a fluorine atom (hereinafter sometimes referred to as “structural unit (a4)”) and a non-leaving hydrocarbon group. And a structural unit (s) (hereinafter sometimes referred to as “structural unit (a5)”).

［式（ａ４−０）中、
Ｒ^５は、水素原子又はメチル基を表す。
Ｌ^４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。
Ｌ^３は、炭素数１〜８のペルフルオロアルカンジイル基を表す。
Ｒ^６は、水素原子又はフッ素原子を表す。］ As the structural unit (a4), a structural unit represented by formula (a4-0) can be given.

[In the formula (a4-0),
R ⁵ represents a hydrogen atom or a methyl group.
L ⁴ represents a single bond or an aliphatic saturated hydrocarbon group having 1 to 4 carbon atoms.
L ³ represents a C 1-8 perfluoroalkanediyl group.
R ⁶ represents a hydrogen atom or a fluorine atom. ]

As the perfluoroalkanediyl group of L ³ , a difluoromethylene group, a perfluoroethylene group, a perfluoroethylfluoromethylene group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, a perfluoropropane-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.

L ⁴ is preferably a single bond, a methylene group or an ethylene group, and more preferably a single bond or a methylene group.
L ³ is preferably a C 1-6 perfluoroalkanediyl group, and more preferably a C ^1-3 C perfluoroalkanediyl group.

Examples of the structural unit (a4-0) include the structural units shown below and a structural unit 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。
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）

〔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の脂肪族炭化水素基を表す。
Ａ^a43は、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基又は単結合を表す。
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６以下である。〕
で表される基を表す。
Ｒ^a42は、置換基を有していてもよい炭素数１〜２０の炭化水素基を表す。
ただし、Ａ^a41及びＲ^a４２のうち少なくとも一方は、ハロゲン原子を有する基である。］ As the structural unit (a4), a structural unit represented by formula (a4-1) can be given.

[In the formula (a4-1),
R ^a41 represents a hydrogen atom or a methyl group.
A ^a41 is an alkanediyl group having 1 to 6 carbon atoms which may have a substituent or a formula (a-g1).

[In the formula (a-g1),
s represents 0 or 1.
A ^a42 and A ^a44 each independently represent an ^optionally substituted aliphatic hydrocarbon group having 1 to 5 carbon atoms.
A ^a43 represents an aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent or a single bond.
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 6 or less. ]
Represents a group represented by
R ^a42 represents an ^optionally substituted hydrocarbon group having 1 to 20 carbon atoms.
However, at least one of A ^a41 and R ^a42 is a group having a halogen atom. ]

As a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned, Preferably it is a fluorine atom.
The aliphatic hydrocarbon group may have a carbon-carbon unsaturated bond, but is preferably an aliphatic saturated hydrocarbon group. As the aliphatic saturated hydrocarbon group, an alkyl group (the alkyl group may be linear or branched) and an alicyclic hydrocarbon group, and an alkyl group and an alicyclic hydrocarbon group are combined. Examples thereof include aliphatic hydrocarbon groups that are formed.

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が挙げられる。 ^Examples of the hydrocarbon group for R ^a42 include chain and cyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining them. Examples of chain aliphatic hydrocarbon groups include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, and n-decyl. Group, n-dodecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group and n-octadecyl group. Cyclic aliphatic hydrocarbon groups include cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and other cycloalkyl groups; decahydronaphthyl group, adamantyl group, norbornyl group and the following groups (* is a bond) And a polycyclic alicyclic hydrocarbon group of a polycyclic alicyclic hydrocarbon group such as.

Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthryl group, a biphenylyl group, a phenanthryl group, and a fluorenyl group.

［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３〜１７の脂肪族炭化水素基を表す。］
Ｒ^a4２が、式（ａ−ｇ３）で表される基を有する脂肪族炭化水素基である場合、式（ａ−ｇ３）で表される基に含まれる炭素数を含めて、脂肪族炭化水素基の総炭素数は、１５以下が好ましく、１２以下がより好ましい。式（ａ−ｇ３）で表される基を置換基として有する場合、その数は１個が好ましい。 The hydrocarbon group for R ^a42 is preferably a chain or cyclic aliphatic hydrocarbon group or a group formed by a combination thereof, and may have a carbon-carbon unsaturated bond. And a cyclic aliphatic saturated hydrocarbon group and a group formed by combining these are more preferable.
As the aliphatic hydrocarbon group, an alkyl group and an alicyclic hydrocarbon group are preferable.
Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n-octyl group and 2 -An ethylhexyl group is mentioned.
The alicyclic hydrocarbon group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, cycloheptyl group, and cyclodecyl group. A cycloalkyl group is mentioned. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1- (adamantan-1-yl) alkane-1-yl group, norbornyl group, A methyl norbornyl group and an isobornyl group are mentioned.
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 the formula (a-g3). .

[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 ^3-17 aliphatic hydrocarbon group having at least one halogen atom. ]
When R ^a42 is an aliphatic hydrocarbon group having a group represented by the formula (a-g3), including the number of carbons contained in the group represented by the formula (a-g3), the aliphatic hydrocarbon The total carbon number of the group is preferably 15 or less, more preferably 12 or less. When it has a group represented by the formula (a-g3) as a substituent, the number is preferably 1.

［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３〜１７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３〜１７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。］ The aliphatic hydrocarbon having a group represented by the formula (a-g3) is more preferably a group represented by the formula (a-g2).

[In the formula (a-g2),
A ^a46 represents an aliphatic hydrocarbon group having 3 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 3 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. ]

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, and still more preferably a carbon number. It is a 1-6 perfluoroalkyl group, Most preferably, it is a C1-C3 perfluoroalkyl group. Examples of the perfluoroalkyl group include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, a perfluorohexyl group, a perfluoroheptyl group, and a perfluorooctyl group. Examples of the perfluorocycloalkyl group include a perfluorocyclohexyl group.

1-6 are preferable and, as for carbon number of the aliphatic hydrocarbon group of ^Aa46 , 1-3 are more preferable.
4-15 are preferable, as for carbon number of the aliphatic hydrocarbon group of A ^<a47> , 5-12 are more preferable, and A ^<a47> has a more preferable cyclohexyl group or an adamantyl group.

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

^As the alkanediyl group of ^Aa41 , a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group Linear alkanediyl group such as propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-methylbutane-1,4-diyl group, Examples include branched alkanediyl groups such as 2-methylbutane-1,4-diyl group.
^Examples of the substituent in 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.

In the group represented by the formula (a-g1) of A ^a41 (hereinafter sometimes referred to as “group (a-g1)”), A ^a44 is ^bonded to —O—CO—R ^a42 .
As the aliphatic hydrocarbon group for A ^a42 , A ^a43 and A ^{a44 in} the group (a-g1), a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane- Examples include 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. Examples of these substituents include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms.

^Examples of the group ( ^{ag1) 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 ** is a bond with —O—CO—R ^a42 .

［式（ａ４−２）中、
Ｒ^ｆ1は、水素原子又はメチル基を表す。
Ａ^ｆ1は、炭素数１〜６のアルカンジイル基を表す。
Ｒ^ｆ2は、フッ素原子を有する炭素数１〜１０の炭化水素基を表す。］ As the structural unit represented by the formula (a4-1), structural units represented by the formula (a4-2) and the formula (a4-3) are preferable.

[In the formula (a4-2),
R ^f1 represents a hydrogen atom or a methyl group.
A ^f1 represents an alkanediyl group having 1 to 6 carbon atoms.
R ^f2 represents a C 1-10 hydrocarbon group having a fluorine atom. ]

As the alkanediyl group of A ^f1 , a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group , A straight-chain alkanediyl group such as hexane-1,6-diyl group; 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2 -Branched alkanediyl groups such as a diyl group, 1-methylbutane-1,4-diyl group, 2-methylbutane-1,4-diyl group.

The hydrocarbon group of R ^f2 includes an aliphatic hydrocarbon group and an aromatic hydrocarbon group, and the aliphatic hydrocarbon group includes a chain, a cyclic group, and a group formed by a combination thereof. As the aliphatic hydrocarbon group, an alkyl group and an alicyclic hydrocarbon group are preferable.
Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n-octyl group and 2 -An ethylhexyl group is mentioned.
The alicyclic hydrocarbon group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, cycloheptyl group, and cyclodecyl group. A cycloalkyl group is mentioned. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1- (adamantan-1-yl) alkane-1-yl group, norbornyl group, A methyl norbornyl group and an isobornyl group are mentioned.

Examples of the hydrocarbon group having a fluorine atom for R ^f2 include an alkyl group having a fluorine atom and an alicyclic hydrocarbon group having a fluorine atom.
Examples of the alkyl group having a fluorine atom include a difluoromethyl group, a trifluoromethyl group, a 1,1-difluoroethyl group, a 2,2-difluoroethyl group, a 2,2,2-trifluoroethyl group, a 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, 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-decafluoro Pentyl group, 1,1-bis (trifluoromethyl) -2,2,3,3,3-pentafluoropropyl group, perfluoropentyl 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-dodecafluorohexyl group, perfluoropentylmethyl group And a fluorinated alkyl group such as a perfluorohexyl group.
Examples of the alicyclic hydrocarbon group having a fluorine atom include fluorinated cycloalkyl groups such as a perfluorocyclohexyl group and a perfluoroadamantyl group.

In formula (a4-2), an alkanediyl group having 2 to 4 carbon atoms is preferable, and as A ^f1 , an ethylene group is more preferable.
R ^f2 is preferably a fluorinated alkyl group having 1 to 6 carbon atoms.

［式（ａ４−３）中、
Ｒ^ｆ11は、水素原子又はメチル基を表す。
Ａ^ｆ11は、炭素数１〜６のアルカンジイル基を表す。
Ａ^ｆ13は、フッ素原子を有していてもよい炭素数１〜１８の脂肪族炭化水素基を表す。
Ｘ^ｆ12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^ｆ14は、フッ素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^ｆ13及びＡ^ｆ14の少なくとも１つは、フッ素原子を有する脂肪族炭化水素基を表す。］

[In the formula (a4-3),
R ^f11 represents a hydrogen atom or a methyl group.
A ^f11 represents an alkanediyl group having 1 to 6 carbon atoms.
A ^f13 represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a fluorine atom.
X ^f12 represents a carbonyloxy group or an oxycarbonyl group.
A ^f14 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom. However, at least one of A ^f13 and A ^f14 represents an aliphatic hydrocarbon group having a fluorine atom. ]

^Examples of the alkanediyl group for A ^f11 include the same groups as the alkanediyl group for A ^f1 .

The aliphatic hydrocarbon group for A ^f13 includes chain and cyclic aliphatic hydrocarbon groups, and divalent aliphatic hydrocarbon groups formed by combining them. The aliphatic hydrocarbon may have a carbon-carbon unsaturated bond, but is preferably a saturated aliphatic hydrocarbon group.
The aliphatic hydrocarbon group which may have a fluorine atom of A ^f13 is preferably an aliphatic saturated hydrocarbon group which may have a fluorine atom, and more preferably a perfluoroalkanediyl group.
Examples of the divalent chain aliphatic hydrocarbon group which may have a fluorine atom include alkanediyl groups such as methylene group, ethylene group, propanediyl group, butanediyl group and pentanediyl group; difluoromethylene group, perfluoroethylene Groups, perfluoroalkanediyl groups such as perfluoropropanediyl group, perfluorobutanediyl group and perfluoropentanediyl group.
The divalent cyclic aliphatic hydrocarbon group which may have a fluorine atom may be either monocyclic or polycyclic. Examples of the monocyclic aliphatic hydrocarbon group include a cyclohexanediyl group and a perfluorocyclohexanediyl group. Examples of the polycyclic divalent aliphatic hydrocarbon group include an adamantanediyl group, a norbornanediyl group, a perfluoroadamantanediyl group, and the like.

As the aliphatic hydrocarbon group for A ^f14 , one of a chain type and a cyclic type, and an aliphatic hydrocarbon group formed by combining them are included. The aliphatic hydrocarbon may have a carbon-carbon unsaturated bond, but is preferably a saturated aliphatic hydrocarbon group.
The aliphatic hydrocarbon group which may have a fluorine atom for A ^f14 is preferably an aliphatic saturated hydrocarbon group which may have a fluorine atom.
Examples of the chain aliphatic hydrocarbon group which may have a fluorine atom 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, pentyl group, hexyl group, perfluorohexyl group, A heptyl group, a perfluoro heptyl group, an octyl group, a perfluorooctyl group, etc. are mentioned.
Etc.
The cyclic aliphatic hydrocarbon group which may have a fluorine atom may be monocyclic or polycyclic. Examples of the group containing a monocyclic aliphatic hydrocarbon group include a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, and a perfluorocyclohexyl group. Examples of the group containing a polycyclic aliphatic hydrocarbon group include an adamantyl group, an adamantylmethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group, and a perfluoroadamantylmethyl group.

In the formula (a4-3), ^{A f11} is an ethylene group is preferred.
The aliphatic hydrocarbon group for A ^f13 is preferably an aliphatic hydrocarbon group having 1 to 6 carbon atoms, and more preferably an aliphatic hydrocarbon group having 2 to 3 carbon atoms.
The aliphatic hydrocarbon group for A ^f14 is preferably an aliphatic hydrocarbon group having 3 to 12 carbon atoms, and more preferably an aliphatic hydrocarbon group having 3 to 10 carbon atoms. Among them, A ^f14 is preferably a group containing an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a cyclopropylmethyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group.

Examples of the monomer for deriving the structural unit represented by formula (a4-2) include monomers represented by formula (a4-1-1) to formula (a4-1-22).

Examples of the monomer that derives the structural unit represented by the formula (a4-3) include monomers represented by the formula (a4-1′-1) to the formula (a4-1′-22).

［式（ａ４−４）中、
Ｒ^f21は、水素原子又はメチル基を表す。
Ａ^f21は、−（ＣＨ_２）_ｊ１−、−（ＣＨ_２）_ｊ２−Ｏ−（ＣＨ_２）_ｊ３−又は−（ＣＨ_２）_ｊ４−ＣＯ−Ｏ−（ＣＨ_２）_ｊ５−を表す。
ｊ１〜ｊ５は、それぞれ独立に、１〜６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。］ Examples of the structural unit (a4) include a structural unit represented by the formula (a4-4).

[In the 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 represents an integer of 1 to 6.
R ^f22 represents a C 1-10 hydrocarbon group having a fluorine atom. ]

^Examples of the hydrocarbon group having a fluorine atom of R ^f22 include the same hydrocarbon groups as R ^f2 in formula (a4-2). R ^f22 is preferably a ^C 1-10 alkyl group having a fluorine atom or a C 1-10 alicyclic hydrocarbon group having a fluorine atom, more preferably a C 1-10 alkyl group having a fluorine atom. Preferably, the C1-C6 alkyl group which has a fluorine atom is further more preferable.

In Formula (a4-4), as A ^f21 , — (CH ₂ ) _j1 — is preferable, an ethylene group or a methylene group is more preferable, and a methylene group is further preferable.

Examples of the monomer for deriving the structural unit represented by the formula (a4-4) include the following monomers.

  When the resin (A1) has the structural unit (a4), the content is preferably from 1 to 20 mol%, more preferably from 2 to 15 mol%, based on all structural units of the resin (A1). More preferably, it is 10 mol%.

［式（ａ５−１）中、
Ｒ^５１は、水素原子又はメチル基を表す。
Ｒ^５２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又はヒドロキシ基で置換されていてもよい。但し、Ｌ^５１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^５１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。］ Examples of the non-leaving hydrocarbon group that the structural unit (a5) has include a linear, branched, or cyclic hydrocarbon group. Especially, it is preferable that a structural unit (a5) has an alicyclic hydrocarbon group. As a structural unit (a5), the structural unit represented by a formula (a5-1) is mentioned, for example.

[In the formula (a5-1),
R ⁵¹ 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 is substituted with an aliphatic hydrocarbon group or hydroxy group having 1 to 8 carbon atoms. May be. However, the hydrogen atom bonded to the carbon atom at the coupling position with the L ⁵¹ is not substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms.
L ⁵¹ 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 the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include an adamantyl group and a norbornyl group.
Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, Examples thereof include alkyl groups such as octyl group and 2-ethylhexyl group.
Examples of the alicyclic hydrocarbon group having a substituent include a 3-hydroxyadamantyl group and a 3-methyladamantyl group.
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.

Examples of the divalent saturated hydrocarbon group for L ⁵¹ include a divalent aliphatic saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, preferably a divalent aliphatic saturated hydrocarbon group. It is done.
Examples of the divalent aliphatic saturated hydrocarbon group include alkanediyl groups such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group, and a pentanediyl group.
The divalent alicyclic saturated hydrocarbon group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic saturated hydrocarbon group include cycloalkanediyl groups such as cyclopentanediyl group and cyclohexanediyl group. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include 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、互いに独立に、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^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 group in which the methylene group contained in the saturated hydrocarbon 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 the 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 aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms.
However, the total carbon number of L ^{x5 to} L ^x7 is 15 or less.
In formula (L1-4),
L ^x8 and L ^x9 represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms.
W ^x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms.
However, the total number of carbon atoms of L ^x8 , L ^x9 and W ^x1 is 15 or less. ]

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

As group represented by a formula (L1-1), the bivalent group shown below is mentioned, for example.

As group represented by a formula (L1-2), the bivalent group shown below is mentioned, for example.

As group represented by a formula (L1-3), the bivalent group shown below is mentioned, for example.

As group represented by a formula (L1-4), the bivalent group shown below is mentioned, for example.

L ⁵¹ is preferably a single bond or a group represented by the formula (L1-1).

Examples of the structural unit (a5-1) include the following.

  The resin (A1) may have a structural unit other than the above-described structural units, and examples of the structural unit include structural units well known in the art.

The resin (A1) is preferably a resin comprising the structural unit (II), the structural unit (a1), and the structural unit (s), that is, the monomer (II ′), the monomer (a1), and the monomer (s). It is a copolymer.
The structural unit (a1) is preferably at least one of the structural unit (a1-1) and the structural unit (a1-2) (preferably the structural unit having a cyclohexyl group or a cyclopentyl group), more preferably the structural unit (a1- 1).
The structural unit (s) is preferably at least one of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably a structural unit represented by the formula (a2-1). The structural unit (a3) is preferably at least one of a structural unit represented by the formula (a3-1) and a structural unit represented by the formula (a3-2).

  The resin (A1) contains a structural unit derived from a monomer having an adamantyl group (particularly the structural unit (a1-1)) in an amount of 15 mol% or more based on the content of the structural unit (a1). preferable. When the content of the structural unit having an adamantyl group is increased, the dry etching resistance of the resist pattern is improved.

Each structural unit constituting the resin (A1) may be used alone or in combination of two or more, and is produced by a known polymerization method (for example, radical polymerization method) using a monomer that derives these structural units. can do. The content rate of each structural unit which resin (A1) has can be adjusted with the usage-amount of the monomer used for superposition | polymerization.
The weight average molecular weight of the resin (A1) is preferably 2,000 or more (more preferably 2,500 or more, more preferably 3,000 or more), 50,000 or less (more preferably 30,000 or less, and further preferably 15,000 or less).

<Resin (A2)>
The resin (A2) is a resin that contains a fluorine atom and does not contain a structural unit having an acid labile group. As such a resin, a resin including the structural unit (a4) (however, the structural unit (a1) is not included) is preferable, and a resin including the structural unit (a4-0) is more preferable. In the resin (A2), the content of the structural unit (a4) is preferably 40 mol% or more, more preferably 45 mol% or more, and still more preferably 50 mol% or more with respect to all the structural units of the resin (A2). .
Examples of the structural unit that the resin (A2) may further include a structural unit derived from the structural unit (a2), the structural unit (a3), the structural unit (a5), and other known monomers.
The weight average molecular weight of the resin (A2) 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 the resin (A2) is the same as that for the resin (A1).
When the resist composition of this invention contains resin (A2), the content becomes like this. Preferably it is 1-60 mass parts with respect to 100 mass parts of resin (A1), More preferably, it is 3-50 mass parts. More preferably, it is 5-40 mass parts, Most preferably, it is 7-30 mass parts.

  As for the total content rate of resin (A1) and resin (A2), 80 to 99 mass% is preferable with respect to solid content of a resist composition. In the present specification, the “solid content of the resist composition” means the total of components excluding the solvent (E) described later from the total amount of the resist composition. The solid content of the resist composition and the resin content relative thereto can be measured by a known analysis means such as liquid chromatography or gas chromatography.

<Acid generator (Ba)>
The acid generator (Ba) is an acid generator containing an anion having 3 to 18 fluorine atoms. Specific examples include onium salts containing onium cations (for example, diazonium salts, phosphonium salts, sulfonium salts, iodonium salts). Examples of anions of onium salts include sulfonate anions, sulfonylimide anions, sulfonylmethide anions, and the like. Can be mentioned.

  The acid generator (Ba) preferably includes an anion having a cyclic structure and having 3 to 18 fluorine atoms.

［式（Ｉ）中、
Ｑ¹及びＱ²は、互いに独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｌ²は、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。
環Ｗは、炭素数３〜３６の脂環式炭化水素環を表し、該脂環式炭化水素環に含まれるメチレン基は、酸素原子、硫黄原子、カルボニル基又はスルホニル基で置き換わっていてもよく、該脂環式炭化水素環に含まれる水素原子は、ヒドロキシ基、炭素数１〜１２の飽和炭化水素基、炭素数１〜１２のアルコキシ基又は炭素数６〜１０の芳香族炭化水素基で置換されていてもよい。
Ｒ^f1及びＲ^f2は、互いに独立に、フッ素原子又は炭素数１〜６のフッ化アルキル基を表す。
ｎは、１〜８の整数を表す。
Ｚ^＋は、有機カチオンを表す。
ただし、式（Ｉ）のアニオン中に含まれるフッ素原子は３〜１８個である。］ The acid generator (Ba) is preferably an acid generator represented by the formula (I).

[In the formula (I),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
L ² represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, and —CH ₂ — contained in the divalent saturated hydrocarbon group may be replaced by —O— or —CO—. The hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group.
Ring W represents an alicyclic hydrocarbon ring having 3 to 36 carbon atoms, and the methylene group contained in the alicyclic hydrocarbon ring may be replaced with an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group. The hydrogen atom contained in the alicyclic hydrocarbon ring is a hydroxy group, a saturated hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms. May be substituted.
R ^f1 and R ^f2 each independently represent a fluorine atom or a fluorinated alkyl group having 1 to 6 carbon atoms.
n represents an integer of 1 to 8.
Z ⁺ represents an organic cation.
However, the number of fluorine atoms contained in the anion of formula (I) is 3 to 18. ]

In the formula (I), a compound having a negative charge formed by removing an organic cation represented by Z ⁺ having a positive charge may be referred to as a “sulfonate anion”.

Examples of the C 1-6 perfluoroalkyl group represented by Q ¹ and Q ² include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, A perfluoro tert-butyl group, a perfluoropentyl group, a perfluorohexyl group and the like can be mentioned.
Q ¹ and Q ² are preferably each independently a trifluoromethyl group or a fluorine atom, more preferably a fluorine atom.

Examples of the divalent saturated hydrocarbon group represented by L ² include alkanediyl groups, monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups, and two or more of these groups. May be combined.
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, 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 Valent alicyclic saturated hydrocarbon group;
Polycyclic divalent alicyclic saturated hydrocarbon such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. Groups and the like.

Examples of the group in which —CH ₂ — contained in the divalent saturated hydrocarbon group represented by L ² is replaced by —O— or —CO— include any of formula (b1-1) to formula (b1-3). The group represented by is mentioned. In the formulas (b1-1) to (b1-3) and the following specific examples, * represents a bond with -W.

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。

In formula (b1-1),
L ^b2 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the 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, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, The methylene group contained in the hydrocarbon group may be replaced 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 the 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, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, The methylene group contained in the hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
However, the total carbon number 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 the 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, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, The methylene group contained in the hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
However, the total carbon number 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 carbons before the replacement is represented by the saturated hydrocarbon group. The number of carbons.
Examples of the divalent saturated hydrocarbon group include those similar to the divalent saturated hydrocarbon group of L ^b1 .

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

  Among these, a group represented by the formula (b1-1) or the formula (b1-3) is preferable.

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^b14及び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^b17及びＬ^b18の合計炭素数は１９以下である。 Examples of formula (b1-1) include groups represented by formula (b1-4) to formula (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 the 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 the hydrogen atom contained in the 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 ^C 1-20 divalent saturated hydrocarbon group, and the hydrogen atom contained in the 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 C 1-18 divalent saturated hydrocarbon group, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group.
However, the total carbon number of L ^b13 , L ^b14 and 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 the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group.
However, the total carbon number of L ^b16 , L ^b17 and L ^b18 is 19 or less.

L ^b8 is preferably an alkanediyl 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 divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms.
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 divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^b16 preferably represents a divalent saturated hydrocarbon group having 1 to 12 carbon atoms.
L ^b17 preferably represents a ^C 1-6 divalent saturated hydrocarbon group.
L ^b18 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms,

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^b22及び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^b25及びＬ^b26の合計炭素数は２１以下である。 Examples of formula (b1-3) include groups represented by formula (b1-9) to formula (b1-11), respectively.

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

  In formulas (b1-10) and (b1-11), when a hydrogen atom contained in a saturated hydrocarbon group is substituted with an acyloxy group, the number of carbon atoms in the acyloxy group, CO and O in the ester bond And the number of carbon atoms of the saturated hydrocarbon group.

Examples of the acyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, a cyclohexylcarbonyloxy group, and an adamantylcarbonyloxy group.
Examples of the acyloxy group having a substituent include an oxoadamantylcarbonyloxy group, a hydroxyadamantylcarbonyloxy group, an oxocyclohexylcarbonyloxy group, and a hydroxycyclohexylcarbonyloxy group.

Of the groups represented by formula (b1-1), examples of the group represented by formula (b1-4) include the following.

Of the groups represented by the formula (b1-1), examples of the group represented by the formula (b1-5) include the following.

Of the groups represented by formula (b1-1), examples of the group represented by formula (b1-6) include the following.

Of the groups represented by the formula (b1-1), examples of the group represented by the formula (b1-7) include the following.

Of the groups represented by the formula (b1-1), examples of the group represented by the formula (b1-8) include the following.

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

Of the groups represented by formula (b1-3), examples of the group represented by formula (b1-9) include the following.

Of the groups represented by the formula (b1-3), examples of the group represented by the formula (b1-10) include the following.

Of the groups represented by formula (b1-3), examples of the group represented by formula (b1-11) include the following.

Examples of the sulfonate anion include the following anions.

  As the sulfonate anion, anions represented by formulas (Ia-2-1) to (Ia-2-9) are preferable.

Examples of the organic cation represented by Z ⁺ include organic onium cations such as organic sulfonium cation, organic iodonium cation, organic ammonium cation, benzothiazolium cation, and organic phosphonium cation. Among these, an organic sulfonium cation and an organic iodonium cation are preferable, and an arylsulfonium cation is more preferable.

  Among these, cations represented by the formulas (b2-1) to (b2-4) (hereinafter may be referred to as “cations (b2-1)” depending on the formula number) are preferable.

In formula (b2-1) to formula (b2-4),
R ^{b4 to} R ^b6 each independently represents an aliphatic hydrocarbon 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, The hydrogen atom contained in the aliphatic hydrocarbon group is 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 aliphatic hydrocarbon group having 1 to 18 carbon atoms, an acyl group having 2 to 4 carbon atoms, or a glycidyloxy group. The hydrogen atom contained in the aromatic 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 together form a ring containing a sulfur atom to which they are bonded, and the -methylene group contained in the ring may be replaced by an oxygen atom, a sulfinyl group or a carbonyl group. Good.

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 aliphatic hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms.
R ^b9 and R ^b10 together may form a ring containing a sulfur atom to which they are bonded, and the methylene group contained in the ring is replaced by an oxygen atom, a sulfur atom, a sulfinyl group or a carbonyl group. May be.
R ^b11 represents a hydrogen atom, an aliphatic hydrocarbon 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 aliphatic hydrocarbon 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 is included in the aliphatic hydrocarbon The hydrogen atom 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 1 to 1 carbon atoms. It may be substituted with 12 alkylcarbonyloxy groups.
R ^b11 and R ^b12 may together form a ring containing —CH—CO— to which they are bonded, and the methylene group contained in the ring is bonded to an oxygen atom, a sulfinyl group or a carbonyl group. It may be replaced.

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 ^b11 represents a sulfur atom or an oxygen atom.
o2, p2, s2, and t2 each independently represents an integer of 0 to 5.
q2 and r2 each independently represents an integer of 0 to 4.
u2 represents 0 or 1.
When o2 is 2 or more, multiple R ^b13 are the same or different, when p2 is 2 or more, multiple R ^b14 are the same or different, and when q2 is 2 or more, multiple R ^b15 are the same or different , When r2 is 2 or more, a plurality of R ^b16 are the same or different, when s2 is 2 or more, a plurality of R ^b17 are the same or different, and when t2 is 2 or more, a plurality of R ^b18 are the same or different Different.

特に、Ｒ^b9〜Ｒ^b12の脂環式炭化水素基は、好ましくは炭素数３〜１８、より好ましくは炭素数４〜１２である。 Examples of the aliphatic hydrocarbon group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, and n-octyl group. And an alkyl group of 2-ethylhexyl group. In particular, the aliphatic hydrocarbon group represented by R ^{b9 to} R ^b12 preferably has 1 to 12 carbon atoms.
The alicyclic hydrocarbon group may be monocyclic or polycyclic, and the monocyclic alicyclic hydrocarbon group may be a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclo group. Examples thereof include cycloalkyl groups such as heptyl group, cyclooctyl group and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, and the following groups.

In particular, the alicyclic hydrocarbon group of R ^{b9 to} R ^b12 preferably has 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.

  Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-alkyladamantan-2-yl group, a methylnorbornyl group, and an isobornyl group. Groups and the like. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms of the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less.

As aromatic hydrocarbon group, phenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, p-ethylphenyl group, p-tert-butylphenyl group, p-cyclohexylphenyl group, p-adamantylphenyl group , Aryl groups such as a biphenylyl group, a naphthyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group.
When the aromatic hydrocarbon group includes an aliphatic hydrocarbon group or an alicyclic hydrocarbon group, the aliphatic hydrocarbon group having 1 to 18 carbon atoms and the alicyclic hydrocarbon having 3 to 18 carbon atoms Groups are preferred.
Examples of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group include a p-methoxyphenyl group.
Examples of the aliphatic hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group.

Alkoxy groups include methoxy, ethoxy, n-propoxy, n-butoxy, n-pentyloxy, n-hexyloxy, n-heptyloxy, n-octyloxy, n-decyloxy and Examples include n-dodecyloxy group.
Examples of the acyl group include an acetyl group, a propionyl group, and an n-butyryl group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
Examples of the alkylcarbonyloxy group include 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, Examples include an n-pentylcarbonyloxy group, an n-hexylcarbonyloxy group, an n-octylcarbonyloxy group, and a 2-ethylhexylcarbonyloxy group.

The ring containing a sulfur atom formed by combining R ^b4 and R ^b5 may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. . Examples of the ring include a ring having 3 to 18 carbon atoms, and a ring having 4 to 18 carbon atoms is preferable. Moreover, the ring containing a sulfur atom includes a 3-membered ring to a 12-membered ring, and preferably a 3-membered ring to a 7-membered ring. The following rings are mentioned.

The ring formed by combining R ^b9 and R ^b10 may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes a 3-membered ring to a 12-membered ring, preferably a 3-membered ring to a 7-membered ring. Examples thereof include a thiolane-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, and a 1,4-oxathian-4-ium ring.
The ring formed by ^combining R ^b11 and R ^b12 may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes a 3-membered ring to a 12-membered ring, preferably a 3-membered ring to a 7-membered ring. Examples thereof include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

［式（ＩＩ）中、
Ｒ^II3、Ｒ^II4、Ｒ^II5、Ｒ^II6及びＲ^II7は、それぞれ独立に、水素原子、ヒドロキシ基、炭素数１〜１２のアルキル基を表し、該アルキル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。
スルホニルカチオンを含む環に含まれるメチレン基は、酸素原子、硫黄原子又はカルボニル基で置き換わっていてもよい。
ｒは、１〜３の整数を表す。
ｓは、０〜３の整数を表す。
Ｒ^II8は、炭素数１〜６のアルキル基を表す。ｓが２以上のとき、複数のＲ^II8は、同一又は相異なる。］ Among the cations (b2-1) to (b2-4), the cation (b2-1) is preferable, and the cation represented by the formula (Ic) is more preferable.

[In the formula (II),
^{R II3, R II4, R II5} , R II6 and R ^II7 each independently represent a hydrogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, a methylene group contained in the alkyl group, an oxygen atom or It may be replaced with a carbonyl group.
The methylene group contained in the ring containing the sulfonyl cation may be replaced with an oxygen atom, a sulfur atom or a carbonyl group.
r represents an integer of 1 to 3.
s represents an integer of 0 to 3.
R ^II8 represents an alkyl group having 1 to 6 carbon atoms. When s is 2 or more, the plurality of R ^II8 are the same or different. ]

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.

  Among these, cation (b2-c-21) to cation (b2-c-27), which are cations represented by formula (Ic), are preferable.

Examples of the acid generator (Ba) include acid generators described in Tables 1 and 2. In Table 1, salt (I-1) is an acid generator shown below.

  Examples of the acid generator (Ba) include an acid generator (I-2), an acid generator (I-3), an acid generator (I-6), an acid generator (I-7), and an acid generator (I -7), acid generator (I-10), acid generator (I-11), acid generator (I-14), acid generator (I-15), acid generator (I-19), acid The generator (I-20), the acid generator (I-23), the acid generator (I-24), the acid generator (I-26) and the acid generator (I-27) are preferred.

  The production method of the acid generator represented by the above formula (I), which is a representative example of the acid generator (Ba), is as follows.

The salt represented by the formula (Ia) and the compound represented by the formula (Ib) are reacted in an acid catalyst condition such as p-toluenesulfonic acid in a solvent such as 1,2-dichloroethane. As a result, an acid generator represented by the formula (I) is obtained.

The salt represented by the formula (Ia) can be synthesized by the method described in JP2007-224008A.
Examples of the compound represented by the formula (Ib) include 2,2,3,3-tetrafluoro-1,4-butanediol.

In addition to the acid generator (Ba), the resist composition of the present invention may contain an acid generator known in the resist field (hereinafter sometimes referred to as “acid generator (B1)”).
The acid generator (B1) may be a nonionic acid generator or an ionic acid generator. Examples of the nonionic acid generator include organic halides, sulfonate esters (for example, 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4). -Sulfonate), sulfones (for example, disulfone, ketosulfone, sulfonyldiazomethane) and the like. Examples of the ionic acid generator include onium salts containing onium cations (for example, diazonium salts, phosphonium salts, sulfonium salts, iodonium salts) and the like. Examples of the anion of the onium salt include a sulfonate anion, a sulfonylimide anion, and a sulfonylmethide anion.

  The acid generator (B1) is preferably an organic sulfonium salt of an organic sulfonic acid, such as the acid generators described in JP2013-68914A, JP2013-3155A, and JP2013-11905A. Can be mentioned. Specific examples include acid generators represented by formula (B1-1) to formula (B1-28). Among them, the formula (B1-1), formula (B1-2), formula (B1-3), formula (B1-5), formula (B1-6), formula (B1-7), formula (B) containing an arylsulfonium cation B1-11), formula (B1-12), formula (B1-13), formula (B1-14), formula (B1-13), formula (B1-20), formula (B1-21), formula (B1) -23), the formula (B1-24), the formula (B1-25), the formula (B1-26) or the acid generator represented by the formula (B1-29) is preferable.

The total content of the acid generator (Ba) and the acid generator (B1) is preferably 1 part by mass or more, more preferably 3 parts by mass or more, preferably 100 parts by mass of the resin (A1). Is 40 parts by mass or less, more preferably 35 parts by mass or less.
When the resist composition of the present invention contains an acid generator (B1), the ratio of the content of the acid generator (Ba) and the acid generator (B1) (acid generator (Ba): acid generator (B1)) Is usually 5:95 to 95: 5, preferably 10:90 to 90:10, and more preferably 15:85 to 85:15 on a mass basis.

<Solvent (E)>
The resist composition of the present invention usually contains a solvent (E).
The content of the solvent (E) in the resist composition is usually 90% by mass or more, preferably 92% by mass or more, more preferably 94% by mass or more, and usually 99.9% by mass or less, preferably 99% by mass. It is as follows. The content rate of a solvent (E) can be measured with well-known analysis means, such as a liquid chromatography and a 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 Esters such as acetone, methyl isobutyl ketone, ketones such as 2-heptanone and cyclohexanone; cyclic esters such as γ-butyrolactone; and the like. One kind of the solvent (E) may be contained alone, or two or more kinds may be contained.

<Quencher (C)>
The resist composition of the present invention may contain a quencher (C).
The quencher (C) may be a basic nitrogen-containing organic compound or a weak acid salt having a lower acidity than the acid generators (Ba) and (B1). Examples of the basic nitrogen-containing organic compound include amines and ammonium salts. Examples of amines include aliphatic amines and aromatic amines. Aliphatic amines include primary amines, secondary amines and tertiary amines.

  As the quencher (C), 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, tri Hexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexyl Amine, 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-diphenyl Ethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane, 2,2′-methylenebisaniline, imida , 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-pyridyloxy) ethane, di (2-pyridyl) ketone, 4,4 ′ -Dipyridyl sulfide, 4,4'-dipyridyl disulfide, 2,2'-dipyridylamine, 2,2'-dipycolylamine, bipyridine and the like, preferably diisopropylaniline, particularly preferably 2,6- Diisopropylaniline is mentioned.

  As ammonium salts, tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3- (trifluoromethyl) phenyltrimethyl Ammonium hydroxide, tetra-n-butylammonium salicylate, choline and the like can be mentioned.

Examples of the weak acid salt that generates an acid having a lower acidity than the acid generated from the acid generators (Ba) and (B1) include a salt represented by the following formula, a weak acid inner salt represented by the formula (D), Moreover, the salt of Unexamined-Japanese-Patent No. 2012-229206, Unexamined-Japanese-Patent No. 2012-6908, Unexamined-Japanese-Patent No. 2012-72109, Unexamined-Japanese-Patent No. 2011-39502, and Unexamined-Japanese-Patent No. 2011-191745 is mentioned.

［式（Ｄ）中、
Ｒ^Ｄ１及びＲ^Ｄ２は、それぞれ独立に、炭素数１〜１２の１価の炭化水素基、炭素数１〜６のアルコキシ基、炭素数２〜７のアシル基、炭素数２〜７のアシルオキシ基、炭素数２〜７のアルコキシカルボニル基、ニトロ基又はハロゲン原子を表す。
ｍ’及びｎ’は、それぞれ独立に、０〜４の整数を表し、ｍ’が２以上の場合、複数のＲ^Ｄ１は同一又は相異なり、ｎ’が２以上の場合、複数のＲ^Ｄ２は同一又は相異なる。］ <Weak acid inner salt (D)>
The weak acid inner salt (D) is a compound represented by the formula (D).

[In the formula (D),
R ^D1 and R ^D2 are each independently a monovalent hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 7 carbon atoms, or an acyloxy group having 2 to 7 carbon atoms. Represents an alkoxycarbonyl group having 2 to 7 carbon atoms, a nitro group, or a halogen atom.
m ′ and n ′ each independently represents an integer of 0 to 4, and when m ′ is 2 or more, the plurality of R ^D1 are the same or different, and when n ′ is 2 or more, the plurality of R ^D2 are Same or different. ]

In the compound represented by the formula (D), the hydrocarbon groups of R ^D1 and R ^D2 are a monovalent aliphatic hydrocarbon group, a monovalent alicyclic hydrocarbon group, and a monovalent aromatic hydrocarbon. And groups formed by combining these groups.
Examples of the monovalent aliphatic hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, pentyl group, hexyl group, and nonyl group.
The monovalent alicyclic hydrocarbon group may be monocyclic or polycyclic, and may be either saturated or unsaturated. Examples thereof include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclononyl group, and cyclododecyl group, norbornyl group, adamantyl group, and the like.
Examples of the monovalent aromatic hydrocarbon group include phenyl group, 1-naphthyl group, 2-naphthyl group, 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4- Propylphenyl group, 4-isopropylphenyl group, 4-butylphenyl group, 4-t-butylphenyl group, 4-hexylphenyl group, 4-cyclohexylphenyl group, anthryl group, p-adamantylphenyl group, tolyl group, xylyl group , Aryl groups such as cumenyl group, mesityl group, biphenyl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl, and the like.
Examples of the group formed by combining these include an alkyl-cycloalkyl group, a cycloalkyl-alkyl group, an aralkyl group (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.).

Examples of the alkoxy group include a methoxy group and an ethoxy group.
Examples of the acyl group include an acetyl group, a propanoyl group, a benzoyl group, and a cyclohexanecarbonyl group.
Examples of the acyloxy group include a group in which an oxy group (—O—) is bonded to the acyl group.
Examples of the alkoxycarbonyl group include a group in which a carbonyl group (—CO—) is bonded to the above alkoxy group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

In the formula (D), R ^D1 and R ^D2 are each independently an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or 2 to 2 carbon atoms. Preferred are an acyl group having 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 2 to 4 carbon atoms, a nitro group, or a halogen atom.
m ′ and n ′ are each independently preferably an integer of 0 to 2, and more preferably 0. When m ′ is 2 or more, the plurality of R ^D1 are the same or different, and when n ′ is 2 or more, the plurality of R ^D2 are the same or different.

Examples of the compound (D) include the following compounds.

  Compound (D) can be produced by the method described in “Tetrahedron Vol. 45, No. 19, p6281-6296”. Moreover, the compound (D) can use the compound marketed.

  The content of the quencher (C) 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 in the solid content of the resist composition. % By mass.

<Other ingredients>
The resist composition of the present invention may contain components other than the above components (hereinafter sometimes referred to as “other components (F)”) as necessary. The other component (F) is not particularly limited, and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, and the like can be used.

<Preparation of resist composition>
The resist composition of the present invention comprises a resin (A1) and an acid generator (Ba), and a resin (A2), an acid generator (B1), a solvent (E), a quencher (C) used as necessary. And other components (F) can be mixed. The mixing order is arbitrary and is not particularly limited. The temperature at the time of mixing can select an appropriate temperature from 10-40 degreeC according to the kind etc. of resin etc., the solubility with respect to solvents (E), such as resin. An appropriate mixing time can be selected from 0.5 to 24 hours depending on the mixing temperature. The mixing means is 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 resist pattern manufacturing method is:
(1) The process of apply | coating the resist composition of this invention on a board | substrate,
(2) The process of drying the composition after application | coating and forming a composition layer,
(3) a step of exposing the composition layer;
(4) a step of heating the composition layer after exposure, and (5) a step of developing the composition layer after heating.

  The resist composition can be applied onto the substrate by a commonly used apparatus such as a spin coater. Examples of the substrate include an inorganic substrate such as a silicon wafer. 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 composition after coating, the solvent is removed and a composition layer is formed. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking), or using a decompression device. The heating temperature is preferably 50 to 200 ° C., for example, and the heating time is preferably 10 to 180 seconds, for example. The pressure during drying under reduced pressure is preferably about 1 to 1.0 × 10 ⁵ Pa.

The obtained composition layer is usually exposed using an exposure machine. The exposure machine is preferably an immersion exposure machine. Exposure light sources include those that emit laser light in the ultraviolet region such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F ₂ excimer laser (wavelength 157 nm), solid-state laser light source (YAG or semiconductor laser) Etc.) Using various lasers such as those that convert wavelength of laser light from the laser and emit harmonic laser light in the far-ultraviolet region or vacuum ultraviolet region, those that irradiate electron beams or extreme ultraviolet light (EUV), etc. Can do. An exposure machine using an ArF excimer laser as an exposure light source is preferable. In this specification, the irradiation of these radiations may be collectively referred to as “exposure”. At the time of exposure, exposure is usually performed through a mask corresponding to a required pattern. When the exposure light source is an electron beam, exposure may be performed by direct drawing without using a mask.

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

  The heated composition layer is usually developed using a developer using a developing device. Examples of the developing method include a dipping method, a paddle method, a spray method, and a dynamic dispensing method. The development temperature is preferably 5 to 60 ° C., for example, and the development time is preferably 5 to 300 seconds, for example. 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 various alkaline aqueous solutions used in this field. Examples thereof include an aqueous solution of tetramethylammonium hydroxide and (2-hydroxyethyl) trimethylammonium hydroxide (commonly known as choline). The alkali developer may contain a surfactant.
It is preferable to wash the resist pattern with ultrapure water after development, and then remove the water remaining on the substrate and the pattern.

In the case of producing a negative resist pattern from the resist composition of the present invention, a developer containing an organic solvent as a developer (hereinafter sometimes referred to as “organic developer”) is used.
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 Examples include ether solvents; amide solvents such as N, N-dimethylacetamide; aromatic hydrocarbon solvents such as anisole.
In the organic developer, the content of the organic solvent 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 only the organic solvent.
Among them, the organic developer is preferably a developer containing butyl acetate and / or 2-heptanone. In the organic developer, the total content of butyl acetate and 2-heptanone is preferably 50% by mass to 100% by mass, more preferably 90% by mass to 100% by mass, and substantially butyl acetate and / or 2 -More preferred is heptanone alone.
The organic developer may contain a surfactant. The organic developer may contain a trace amount of water.
At the time of development, the development may be stopped by substituting a solvent of a different type from the organic developer.

It is preferable to wash the developed resist pattern with a rinse solution. The rinsing 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, and an alcohol solvent or an ester solvent is preferable.
After the cleaning, it is preferable to remove the rinse solution remaining on the substrate and the pattern.

<Application>
The resist composition of the present invention includes 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, particularly ArF. It is suitable as a resist composition for excimer laser exposure and is useful for fine processing of semiconductors.

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 determined 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 molecular peaks using mass spectrometry (LC: Agilent model 1100, MASS: Agilent LC / MSD model). In the following examples, the value of this molecular peak is indicated by “MASS”.

特開２００８−２０９９１７号公報に記載された方法によって得られた式（Ｉ−２６−ｂ）で表される化合物１０．００部、式（Ｉ−２６−ａ）で表される塩１１．２６部、クロロホルム５０部及びイオン交換水２５部を仕込み、２３℃で１５時間攪拌した。得られた反応液が２層に分離していたので、クロロホルム層を分液して取り出し、更に、該クロロホルム層にイオン交換水１５部を添加し、水洗した。この操作を５回繰り返した。クロロホルム層を濃縮し、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル５０部を加えて２３℃で３０分間攪拌した後、ろ過することにより、式（Ｉ−２６−ｃ）で表される塩１１．７５部を得た。 Synthesis Example 1: Synthesis of acid generator represented by formula (I-26)

10.00 parts of a compound represented by the formula (I-26-b) obtained by the method described in JP-A-2008-209917, and a salt represented by the formula (I-26-a) 11.26 Part, chloroform 50 parts and ion-exchanged water 25 parts, and stirred at 23 ° C. for 15 hours. Since the obtained reaction liquid was separated into two layers, the chloroform layer was separated and taken out, and further 15 parts of ion-exchanged water was added to the chloroform layer and washed with water. This operation was repeated 5 times. The chloroform layer was concentrated, 50 parts of tert-butyl methyl ether was added to the resulting residue, the mixture was stirred at 23 ° C. for 30 minutes, and then filtered to obtain the salt 11 represented by the formula (I-26-c). .75 parts were obtained.

式（Ｉ−２６−ｃ）で表される塩１１．７１部、式（Ｉ−２６−ｄ）で表される化合物１．７０部及びモノクロロベンゼン４６．８４部を仕込み、２３℃で３０分間攪拌した。得られた混合液に、二安息香酸銅（ＩＩ）０．１２部を添加した後、更に、１００℃で３０分間攪拌した。得られた反応溶液を濃縮した後、得られた残渣に、クロロホルム５０部及びイオン交換水１２．５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。回収された有機層にイオン交換水１２．５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。この水洗操作を８回繰り返した。得られた有機層を濃縮した後、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル５０部を加えて攪拌した後、ろ過することにより、式（Ｉ−２６−ｅ）で表される塩６．８４部を得た。

11.71 parts of a salt represented by the formula (I-26-c), 1.70 parts of a compound represented by the formula (I-26-d) and 46.84 parts of monochlorobenzene were charged, and the mixture was charged at 23 ° C. for 30 minutes. Stir. After adding 0.12 part of copper (II) dibenzoate to the obtained liquid mixture, it stirred at 100 degreeC for 30 minutes further. After concentrating the obtained reaction solution, 50 parts of chloroform and 12.50 parts of ion-exchanged water were added to the obtained residue and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out an organic layer. 12.50 parts of ion-exchanged water was added to the collected organic layer and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out the organic layer. This washing operation was repeated 8 times. After concentration of the obtained organic layer, 50 parts of tert-butyl methyl ether was added to the obtained residue, stirred, and then filtered to obtain the salt represented by the formula (I-26-e) 6. 84 parts were obtained.

式（Ｉ−２６−ｅ）で表される塩４．９８部及びクロロホルム２５．００部を仕込み、２３℃で３０分間攪拌した。その後、式（Ｉ−２６−ｆ）で表される化合物２．１７部及び硫酸０．０９部を添加し、６０℃で、１５時間還流攪拌した。得られた反応物を２３℃まで冷却し、イオン交換水１２０部を加え、２３℃で３０分間攪拌した。その後、静置し、分液した。回収された有機層に、イオン交換水１２．５０部を仕込み、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７回行った。得られた有機層に活性炭１．００部を仕込み、２３℃で３０分間攪拌し、ろ過した。ろ液を濃縮し、得られた濃縮物に、アセトニトリル１０部を添加して溶解し、濃縮した。これに、ｔｅｒｔ−ブチルメチルエーテル４１．３５部を加えて攪拌した後、上澄液を除去した。得られた残渣をアセトニトリルに溶解し、濃縮することにより、式（Ｉ−２６）で表される酸発生剤４．８４部を得た。

4.98 parts of the salt represented by the formula (I-26-e) and 25.00 parts of chloroform were charged and stirred at 23 ° C. for 30 minutes. Thereafter, 2.17 parts of a compound represented by the formula (I-26-f) and 0.09 part of sulfuric acid were added, and the mixture was refluxed and stirred at 60 ° C. for 15 hours. The obtained reaction product was cooled to 23 ° C., 120 parts of ion exchange water was added, and the mixture was stirred at 23 ° C. for 30 minutes. Then, it left still and liquid-separated. The recovered organic layer was charged with 12.50 parts of ion-exchanged water, stirred at 23 ° C. for 30 minutes, and separated to recover the organic layer. This washing operation was performed 7 times. The obtained organic layer was charged with 1.00 parts of activated carbon, stirred at 23 ° C. for 30 minutes, and filtered. The filtrate was concentrated, and 10 parts of acetonitrile was added to the resulting concentrate to dissolve and concentrate. To this, 41.35 parts of tert-butyl methyl ether was added and stirred, and then the supernatant was removed. The obtained residue was dissolved in acetonitrile and concentrated to obtain 4.84 parts of an acid generator represented by the formula (I-26).

MASS (ESI (+) Spectrum): M ⁺ 237.1
MASS (ESI (−) Spectrum): M ^- 467.1

式（Ｉ−２２−ａ）で表される塩３００部及びクロロホルム７５０部を仕込み、２３℃で３０分間攪拌した。その後、式（Ｉ−２２−ｂ）で表される化合物９７．０７部を添加し、２３℃で１時間攪拌した後、濃縮した。得られた濃縮残渣にｔｅｒｔ−ブチルメチルエーテル１４００部を加えて攪拌した後、ろ過することにより、式（Ｉ−２２−ｃ）で表される塩３４７．８６部を得た。 Synthesis Example 2: Synthesis of acid generator represented by formula (I-22)

300 parts of the salt represented by the formula (I-22-a) and 750 parts of chloroform were charged and stirred at 23 ° C. for 30 minutes. Thereafter, 97.07 parts of a compound represented by the formula (I-22-b) was added, stirred at 23 ° C. for 1 hour, and concentrated. To the obtained concentrated residue, 1400 parts of tert-butyl methyl ether was added and stirred, followed by filtration to obtain 347.86 parts of the salt represented by the formula (I-22-c).

式（Ｉ−２２−ｃ）で表される塩３００部、式（Ｉ−２２−ｄ）で表される化合物６０．７８部及びクロロホルム１５００部を仕込み、２３℃で３０分間攪拌した。得られた混合液に、二酢酸銅（ＩＩ）１．１９部を添加した後、更に、６０℃で５時間還流攪拌した。得られた反応溶液を濃縮した後、得られた濃縮残渣に、アセトニトリル５０部及びｔｅｒｔ−ブチルメチルエーテル１２００部を加えて攪拌した後、ろ過することにより、式（Ｉ−２２−ｅ）で表される塩２０１．９５部を得た。

300 parts of the salt represented by the formula (I-22-c), 60.78 parts of the compound represented by the formula (I-22-d) and 1500 parts of chloroform were charged and stirred at 23 ° C. for 30 minutes. After adding 1.19 parts of copper (II) diacetate to the obtained mixture, the mixture was further stirred at 60 ° C. for 5 hours under reflux. After concentrating the obtained reaction solution, 50 parts of acetonitrile and 1200 parts of tert-butyl methyl ether were added to the resulting concentrated residue, stirred, and then filtered to obtain a compound represented by formula (I-22-e). 201.95 parts of the salt obtained are obtained.

式（Ｉ−２２−ｆ）で表される化合物１３０部、式（Ｉ−２２−ｇ）で表される化合物７３．８３部及びクロロホルム７８０部を仕込み、２３℃で３０分間攪拌した。得られた混合溶液に、硫酸０．４６部を滴下した後、６２℃で２４時間還流攪拌した後、２３℃まで冷却した。得られた反応溶液にトリエチルアミン２．３部添加することにより、式（Ｉ−２２−ｈ）で表される塩１５１．５５部を含む溶液（純度１８．７％）を得た。

130 parts of a compound represented by the formula (I-22-f), 73.83 parts of a compound represented by the formula (I-22-g), and 780 parts of chloroform were charged and stirred at 23 ° C. for 30 minutes. After 0.46 parts of sulfuric acid was added dropwise to the obtained mixed solution, the mixture was stirred at reflux at 62 ° C. for 24 hours, and then cooled to 23 ° C. By adding 2.3 parts of triethylamine to the obtained reaction solution, a solution (purity 18.7%) containing 151.55 parts of the salt represented by the formula (I-22-h) was obtained.

式（Ｉ−２２−ｈ）で表される塩１５１．５５部を含む溶液（純度１８．７％）５０部、式（Ｉ−２２−ｅ）で表される塩６２．５３部及び５％シュウ酸水２０４部を仕込み、２３℃で２時間攪拌した後、分液した。回収された有機層に、イオン交換水２０４部を加え、２３℃で３０分間攪拌した。その後、静置し、分液した。この水洗の操作を４回行った。得られた有機層に活性炭１．００部を仕込み、２３℃で３０分間攪拌し、ろ過した。ろ液を濃縮し、得られた濃縮残渣に、アセトニトリル２０部及びｔｅｒｔ−ブチルメチルエーテル８３０部を加えて攪拌した後、ろ過することにより、式（Ｉ−２２）で表される酸発生剤１０９．７６部を得た。

50 parts of a solution (purity 18.7%) containing 151.55 parts of the salt represented by the formula (I-22-h), 62.53 parts of the salt represented by the formula (I-22-e) and 5% After adding 204 parts of oxalic acid water and stirring at 23 ° C. for 2 hours, liquid separation was performed. To the recovered organic layer, 204 parts of ion-exchanged water was added and stirred at 23 ° C. for 30 minutes. Then, it left still and liquid-separated. This washing operation was performed 4 times. The obtained organic layer was charged with 1.00 parts of activated carbon, stirred at 23 ° C. for 30 minutes, and filtered. The filtrate was concentrated, 20 parts of acetonitrile and 830 parts of tert-butyl methyl ether were added to the resulting concentrated residue, and the mixture was stirred and then filtered to obtain the acid generator 109 represented by formula (I-22). .76 parts were obtained.

MASS (ESI (+) Spectrum): M ⁺ 235.2
MASS (ESI (−) Spectrum): M ^- 467.1

式（Ｉ−１８−ａ）で表される塩５．６２部及びクロロホルム１６．８５部を仕込み、２３℃で３０分間攪拌した。その後、式（Ｉ−１８−ｂ）で表される化合物１．６５部を添加し、２３℃で１時間攪拌した。得られた反応物に、式（Ｉ−２２−ｈ）で表される塩１５１．５５部を含む溶液（純度１８．７％）４０部を仕込み、２３℃で３時間攪拌した。得られた反応物に、イオン交換水１６部を加え、２３℃で３０分間攪拌した。その後、静置し、分液した。この水洗の操作を５回行った。得られた有機層を濃縮し、得られた濃縮残渣に、ｔｅｒｔ−ブチルメチルエーテル６５部を加えて攪拌した後、ろ過することにより、式（Ｉ−１８−ｄ）で表される塩８．６７部を得た。 Synthesis Example 3: Synthesis of acid generator represented by formula (I-18)

5.62 parts of a salt represented by the formula (I-18-a) and 16.85 parts of chloroform were charged and stirred at 23 ° C. for 30 minutes. Thereafter, 1.65 parts of a compound represented by the formula (I-18-b) was added, and the mixture was stirred at 23 ° C. for 1 hour. To the obtained reaction product, 40 parts of a solution (purity: 18.7%) containing 151.55 parts of the salt represented by the formula (I-22-h) was added and stirred at 23 ° C. for 3 hours. To the obtained reaction product, 16 parts of ion exchange water was added and stirred at 23 ° C. for 30 minutes. Then, it left still and liquid-separated. This washing operation was performed 5 times. The obtained organic layer was concentrated, and 65 parts of tert-butyl methyl ether was added to the obtained concentrated residue, stirred, and then filtered to obtain the salt represented by the formula (I-18-d) 8. 67 parts were obtained.

式（Ｉ−１８−ｄ）で表される塩３．９１部、式（Ｉ−１８−ｅ）で表される化合物０．４４部、モノクロロベンゼン６部及びクロロホルム１６部を仕込み、２３℃で３０分間攪拌した。得られた混合液に、二酢酸銅（ＩＩ）０．０１部を添加した後、更に、７５℃で３時間還流攪拌した。得られた反応溶液を２３℃に冷却した後、５％シュウ酸水８部を加え、２３℃で３０分間攪拌した。その後、静置し、分液した。得られた有機層に、イオン交換水８部を加え、２３℃で３０分間攪拌した。その後、静置し、分液した。この水洗の操作を４回行った。得られた有機層を濃縮し、得られた濃縮残渣に、ｔｅｒｔ−ブチルメチルエーテル８部及びｎ−ヘプタン３３部を加えて攪拌した後、ろ過することにより、式（Ｉ−１８）で表される酸発生剤２．７７部を得た。

3.91 parts of a salt represented by the formula (I-18-d), 0.44 part of a compound represented by the formula (I-18-e), 6 parts of monochlorobenzene and 16 parts of chloroform were charged at 23 ° C. Stir for 30 minutes. After adding 0.01 parts of copper (II) diacetate to the obtained mixture, the mixture was further stirred at 75 ° C. for 3 hours under reflux. The resulting reaction solution was cooled to 23 ° C., 8 parts of 5% oxalic acid water was added, and the mixture was stirred at 23 ° C. for 30 minutes. Then, it left still and liquid-separated. To the obtained organic layer, 8 parts of ion-exchanged water was added and stirred at 23 ° C. for 30 minutes. Then, it left still and liquid-separated. This washing operation was performed 4 times. The obtained organic layer was concentrated, 8 parts of tert-butyl methyl ether and 33 parts of n-heptane were added to the resulting concentrated residue, stirred, and then filtered, thereby being represented by the formula (I-18). 2.77 parts of an acid generator was obtained.

MASS (ESI (+) Spectrum): M ⁺ 221.1
MASS (ESI (−) Spectrum): M ^- 467.1

式（Ｉ−２３−ａ）で表される塩２．７６部、式（Ｉ−２３−ｂ）で表される化合物２．１２部及びクロロホルム２８．３５部を仕込み、２３℃で３０分間攪拌した。得られた混合溶液に、硫酸０．０１部を添加した後、６０℃で２０時間還流攪拌した後、２３℃まで冷却した。得られた反応溶液に、イオン交換水１８部を加え、２３℃で３０分間攪拌した。その後、静置し、分液した。この水洗の操作を４回行い、式（Ｉ−２３−ｃ）で表される塩を含む有機層を得た。 Synthesis Example 4: Synthesis of acid generator represented by formula (I-23)

2.76 parts of a salt represented by the formula (I-23-a), 2.12 parts of a compound represented by the formula (I-23-b) and 28.35 parts of chloroform were charged and stirred at 23 ° C. for 30 minutes. did. After adding 0.01 part of sulfuric acid to the obtained mixed solution, the mixture was stirred at 60 ° C. for 20 hours under reflux, and then cooled to 23 ° C. 18 parts of ion-exchanged water was added to the obtained reaction solution, and the mixture was stirred at 23 ° C. for 30 minutes. Then, it left still and liquid-separated. This washing operation was performed 4 times to obtain an organic layer containing a salt represented by the formula (I-23-c).

式（Ｉ−２３−ｃ）で表される塩を含む有機層に、式（Ｉ−２３−ｄ）で表される塩２．５４部及び５％シュウ酸水１４．１８部を仕込み、２３℃で４時間攪拌した後、分液した。回収された有機層に、イオン交換水１４部を加え、２３℃で３０分間攪拌した。その後、静置し、分液した。この水洗の操作を４回行った。得られた有機層に活性炭１．００部を仕込み、２３℃で３０分間攪拌し、ろ過した。ろ液を濃縮し、得られた濃縮残渣に、アセトニトリル１３部及びｔｅｒｔ−ブチルメチルエーテル２５部を加えて攪拌した後、上澄液を除去した。得られた残渣をアセトニトリルに溶解し、濃縮することにより、式（Ｉ−２３）で表される酸発生剤２．９４部を得た。

An organic layer containing a salt represented by the formula (I-23-c) was charged with 2.54 parts of a salt represented by the formula (I-23-d) and 14.18 parts of 5% oxalic acid water, and 23 The mixture was stirred at 4 ° C. for 4 hours and then separated. To the recovered organic layer, 14 parts of ion-exchanged water was added and stirred at 23 ° C. for 30 minutes. Then, it left still and liquid-separated. This washing operation was performed 4 times. The obtained organic layer was charged with 1.00 parts of activated carbon, stirred at 23 ° C. for 30 minutes, and filtered. The filtrate was concentrated, 13 parts of acetonitrile and 25 parts of tert-butyl methyl ether were added to the resulting concentrated residue and stirred, and then the supernatant was removed. The obtained residue was dissolved in acetonitrile and concentrated to obtain 2.94 parts of an acid generator represented by the formula (I-23).

MASS (ESI (+) Spectrum): M ⁺ 235.2
MASS (ESI (−) Spectrum): M ^- 517.1

式（Ｉ−５７−ｂ）で表される塩５．６０部、クロロホルム２４部、式（Ｉ−５７−ａ）で表される塩３．５５部及びアセトニトリル４．８８部を仕込み、２３℃で７２時間攪拌した。得られた反応液に、イオン交換水８．５部を添加し、水洗した。この操作を５回繰り返した。回収された有機層を濃縮し、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル５０部を加えて２３℃で３０分間攪拌した後、ろ過することにより、式（Ｉ−５７）で表される酸発生剤１１．７５部を得た。 Synthesis Example 5: Synthesis of acid generator represented by formula (I-57)

5.60 parts of a salt represented by the formula (I-57-b), 24 parts of chloroform, 3.55 parts of a salt represented by the formula (I-57-a) and 4.88 parts of acetonitrile were charged at 23 ° C. For 72 hours. To the obtained reaction solution, 8.5 parts of ion-exchanged water was added and washed with water. This operation was repeated 5 times. The collected organic layer is concentrated, and 50 parts of tert-butyl methyl ether is added to the resulting residue, followed by stirring at 23 ° C. for 30 minutes, followed by filtration to obtain an acid represented by the formula (I-57). 11.75 parts of generator was obtained.

MASS (ESI (+) Spectrum): M ⁺ 221.1
MASS (ESI (−) Spectrum): M ^- 467.1

式（Ｉ−６１−ａ）で表される塩を、特開２００７−２２４００８号公報に記載された方法で合成した。
式（Ｉ−６１−ａ）で表される塩１０．００部及び１，２−ジクロロエタン４０部を仕込み、２３℃で３０分間攪拌した。その後、式（Ｉ−６１−ｂ）で表される化合物５．５３部及びｐ−トルエンスルホン酸０．３０部を添加し、１００℃で、３時間還流攪拌した。得られた反応物を２３℃まで冷却し、クロロホルム１２０．００部及び８．７％炭酸水素ナトリウム水溶液３５．３９部を加え、２３℃で３０分間攪拌した。その後、静置し、分液した。回収された有機層に、イオン交換水１２０部を仕込み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７回行った。得られた有機層に活性炭１．００部を仕込み、２３℃で３０分間攪拌し、ろ過した。ろ液を濃縮し、得られた濃縮物に、アセトニトリル２０部を添加して溶解し、濃縮した。これに、アセトニトリル８．１４部及びｔｅｒｔ−ブチルメチルエーテル４８．８４部を加えて攪拌し、２３℃で１時間攪拌し、ろ過して、式（Ｉ−６１）で表される酸発生剤８．２５部を得た。 Synthesis Example 6: Synthesis of acid generator represented by formula (I-61)

A salt represented by the formula (I-61-a) was synthesized by the method described in JP-A-2007-224008.
10.00 parts of the salt represented by the formula (I-61-a) and 40 parts of 1,2-dichloroethane were charged and stirred at 23 ° C. for 30 minutes. Thereafter, 5.53 parts of the compound represented by the formula (I-61-b) and 0.30 parts of p-toluenesulfonic acid were added, and the mixture was refluxed and stirred at 100 ° C. for 3 hours. The obtained reaction product was cooled to 23 ° C., 120.00 parts of chloroform and 35.39 parts of an 8.7% aqueous sodium hydrogen carbonate solution were added, and the mixture was stirred at 23 ° C. for 30 minutes. Then, it left still and liquid-separated. To the recovered organic layer, 120 parts of ion-exchanged water was charged, stirred at 23 ° C. for 30 minutes, and separated to recover the organic layer. This washing operation was performed 7 times. The obtained organic layer was charged with 1.00 parts of activated carbon, stirred at 23 ° C. for 30 minutes, and filtered. The filtrate was concentrated, and 20 parts of acetonitrile was added to the resulting concentrate to dissolve and concentrate. To this, 8.14 parts of acetonitrile and 48.84 parts of tert-butyl methyl ether were added and stirred, stirred at 23 ° C. for 1 hour, filtered, and acid generator 8 represented by formula (I-61). .25 parts were obtained.

MS (ESI (+) Spectrum): M ⁺ 263.1
MS (ESI (-) Spectrum): M ^- 467.1

式（Ｉ−６５−ｂ）で表される塩を、特開２００８−９４８３５号公報に記載された方法で合成した。
式（Ｉ−６５−ａ）で表される塩１７．５０部、式（Ｉ−６５−ｂ）で表される塩２５．００部(純度：９０．８％)、クロロホルム１２５．００部及びイオン交換水４１．６７部を仕込み、２３℃で１２時間攪拌し、分液を行った。回収された有機層に、イオン交換水３１．２５部を仕込み、攪拌、分液を行った。この水洗を９回行った。得られた有機層に活性炭１．００部を仕込み、２３℃で３０分間攪拌し、ろ過した。ろ液を濃縮した後、得られた濃縮物に、アセトニトリル５０部を添加して溶解し、濃縮し、得られた残渣にｔｅｒｔ−ブチルメチルエーテル１７３．１３部を加えて攪拌し、ろ過することにより、式（Ｉ−６５−ｃ）で表される塩２８．４２部を得た。 Synthesis Example 7 Synthesis of acid generator represented by formula (I-65)

A salt represented by the formula (I-65-b) was synthesized by the method described in JP 2008-94835 A.
17.50 parts of the salt represented by the formula (I-65-a), 25.00 parts (purity: 90.8%) of the salt represented by the formula (I-65-b), 125.00 parts of chloroform, 41.67 parts of ion-exchanged water was added, and the mixture was stirred at 23 ° C. for 12 hours for liquid separation. The recovered organic layer was charged with 31.25 parts of ion exchanged water, and stirred and separated. This washing with water was performed nine times. The obtained organic layer was charged with 1.00 parts of activated carbon, stirred at 23 ° C. for 30 minutes, and filtered. Concentrate the filtrate, add 50 parts of acetonitrile to the resulting concentrate, dissolve, concentrate, add 173.13 parts of tert-butyl methyl ether to the resulting residue, stir and filter. Gave 28.42 parts of the salt represented by the formula (I-65-c).

式（Ｉ−６５−ｃ）で表される塩１０．７２部及び１，２−ジクロロエタン４２．８８部を仕込み、２３℃で３０分間攪拌した。その後、式（Ｉ−６５−ｄ）で表される化合物５．５３部及びｐ−トルエンスルホン酸０．３０部を添加し、１００℃で、３時間還流攪拌した。得られた反応物を２３℃まで冷却し、クロロホルム１２０．００部及び８．７％炭酸水素ナトリウム水溶液３５．３９部を加え、２３℃で３０分間攪拌した。その後、静置し、分液した。回収された有機層に、イオン交換水１２０部を仕込み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７回行った。得られた有機層に活性炭１．００部を仕込み、２３℃で３０分間攪拌し、ろ過した。ろ液を濃縮し、得られた濃縮物に、アセトニトリル２０部を添加して溶解し、濃縮した。これに、アセトニトリル９．１２部及びｔｅｒｔ−ブチルメチルエーテル５４．７２部を加えて攪拌し、２３℃で１時間攪拌し、ろ過して、式（Ｉ−６５）で表される酸発生剤８．４９部を得た。

10.72 parts of the salt represented by the formula (I-65-c) and 42.88 parts of 1,2-dichloroethane were charged and stirred at 23 ° C. for 30 minutes. Thereafter, 5.53 parts of the compound represented by the formula (I-65-d) and 0.30 parts of p-toluenesulfonic acid were added, and the mixture was refluxed and stirred at 100 ° C. for 3 hours. The obtained reaction product was cooled to 23 ° C., 120.00 parts of chloroform and 35.39 parts of an 8.7% aqueous sodium hydrogen carbonate solution were added, and the mixture was stirred at 23 ° C. for 30 minutes. Then, it left still and liquid-separated. To the recovered organic layer, 120 parts of ion-exchanged water was charged, stirred at 23 ° C. for 30 minutes, and separated to recover the organic layer. This washing operation was performed 7 times. The obtained organic layer was charged with 1.00 parts of activated carbon, stirred at 23 ° C. for 30 minutes, and filtered. The filtrate was concentrated, and 20 parts of acetonitrile was added to the resulting concentrate to dissolve and concentrate. To this, 9.12 parts of acetonitrile and 54.72 parts of tert-butyl methyl ether were added, stirred, stirred at 23 ° C. for 1 hour, filtered, and acid generator 8 represented by formula (I-65). .49 parts were obtained.

MS (ESI (+) Spectrum): M ⁺ 305.1
MS (ESI (-) Spectrum): M ^- 467.1

特開２００８−２０９９１７号公報に記載された方法によって得られた式（Ｂ１−２１−ｂ）で表される化合物３０．００部、式（Ｂ１−２１−ａ）で表される塩３５．５０部、クロロホルム１００部及びイオン交換水５０部を仕込み、２３℃で１５時間攪拌した。得られた反応液が２層に分離していたので、クロロホルム層を分液して取り出し、更に、該クロロホルム層にイオン交換水３０部を添加し、水洗した。この操作を５回繰り返した。クロロホルム層を濃縮し、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル１００部を加えて２３℃で３０分間攪拌した後、ろ過することにより、式（Ｂ１−２１−ｃ）で表される塩４８．５７部を得た。 Synthesis Example 8: Synthesis of acid generator represented by formula (B1-21)

30.00 parts of a compound represented by the formula (B1-21-b) obtained by the method described in JP-A-2008-209917, and a salt 35.50 represented by the formula (B1-21-a). Part, 100 parts of chloroform, and 50 parts of ion-exchanged water were stirred at 23 ° C. for 15 hours. Since the obtained reaction solution was separated into two layers, the chloroform layer was separated and taken out, and 30 parts of ion-exchanged water was further added to the chloroform layer and washed with water. This operation was repeated 5 times. The chloroform layer was concentrated, 100 parts of tert-butyl methyl ether was added to the resulting residue, and the mixture was stirred at 23 ° C. for 30 minutes, and then filtered to obtain the salt 48 represented by the formula (B1-21-c). .57 parts were obtained.

式（Ｂ１−２１−ｃ）で表される塩２０．００部、式（Ｂ１−２１−ｄ）で表される化合物２．８４部及びモノクロロベンゼン２５０部を仕込み、２３℃で３０分間攪拌した。得られた混合液に、二安息香酸銅（ＩＩ）０．２１部を添加した後、更に、１００℃で１時間攪拌した。得られた反応溶液を濃縮した後、得られた残渣に、クロロホルム２００部及びイオン交換水５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。回収された有機層にイオン交換水５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。この水洗操作を５回繰り返した。得られた有機層を濃縮した後、得られた残渣に、アセトニトリル５３．５１部に溶解し、濃縮した後、ｔｅｒｔ−ブチルメチルエーテル１１３．０５部を加えて攪拌した後、ろ過することにより、式（Ｂ１−２１）で表される酸発生剤１０．４７部を得た。

20.00 parts of a salt represented by the formula (B1-21-c), 2.84 parts of a compound represented by the formula (B1-21-d) and 250 parts of monochlorobenzene were charged and stirred at 23 ° C. for 30 minutes. . After adding 0.21 part of copper (II) dibenzoate to the obtained liquid mixture, it stirred at 100 degreeC for further 1 hour. After concentrating the obtained reaction solution, 200 parts of chloroform and 50 parts of ion-exchanged water were added to the obtained residue and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out an organic layer. 50 parts of ion-exchanged water was added to the collected organic layer and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out the organic layer. This washing operation was repeated 5 times. After concentrating the obtained organic layer, the residue obtained was dissolved in 53.51 parts of acetonitrile, concentrated, 113.05 parts of tert-butyl methyl ether was added and stirred, and then filtered. 10.47 parts of acid generators represented by formula (B1-21) were obtained.

MASS (ESI (+) Spectrum): M ⁺ 237.1
MASS (ESI (−) Spectrum): M ^- 339.1

式（Ｂ１−２２−ａ）で表される塩１１．２６部、式（Ｂ１−２２−ｂ）で表される化合物１０．００部、クロロホルム５０部及びイオン交換水２５部を仕込み、２３℃で１５時間攪拌した。得られた反応液が２層に分離していたので、クロロホルム層を分液して取り出し、更に、該クロロホルム層にイオン交換水１５部を添加し、水洗した。この操作を５回繰り返した。クロロホルム層を濃縮し、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル５０部を加えて２３℃で３０分間攪拌した後、ろ過することにより、式（Ｂ１−２２−ｃ）で表される塩１１．７５部を得た。 Synthesis Example 9: Synthesis of acid generator represented by formula (B1-22)

11.26 parts of a salt represented by the formula (B1-22-a), 10.00 parts of a compound represented by the formula (B1-22-b), 50 parts of chloroform and 25 parts of ion-exchanged water were charged at 23 ° C. For 15 hours. Since the obtained reaction liquid was separated into two layers, the chloroform layer was separated and taken out, and further 15 parts of ion-exchanged water was added to the chloroform layer and washed with water. This operation was repeated 5 times. The chloroform layer was concentrated, 50 parts of tert-butyl methyl ether was added to the resulting residue, the mixture was stirred at 23 ° C. for 30 minutes, and then filtered to obtain the salt 11 represented by the formula (B1-22-c). .75 parts were obtained.

式（Ｂ１−２２−ｃ）で表される塩１１．７１部、式（Ｂ１−２２−ｄ）で表される化合物１．７０部及びモノクロロベンゼン４６．８４部を仕込み、２３℃で３０分間攪拌した。得られた混合液に、二安息香酸銅（ＩＩ）０．１２部を添加した後、更に、１００℃で３０分間攪拌した。得られた反応溶液を濃縮した後、得られた残渣に、クロロホルム５０部及びイオン交換水１２．５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。回収された有機層にイオン交換水１２．５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。この水洗操作を８回繰り返した。得られた有機層を濃縮した後、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル５０部を加えて攪拌した後、ろ過することにより、式（Ｂ１−２２）で表される酸発生剤６．８４部を得た。

11.71 parts of a salt represented by the formula (B1-22-c), 1.70 parts of a compound represented by the formula (B1-22-d) and 46.84 parts of monochlorobenzene were charged, and the mixture was charged at 23 ° C. for 30 minutes. Stir. After adding 0.12 part of copper (II) dibenzoate to the obtained liquid mixture, it stirred at 100 degreeC for 30 minutes further. After concentrating the obtained reaction solution, 50 parts of chloroform and 12.50 parts of ion-exchanged water were added to the obtained residue and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out an organic layer. 12.50 parts of ion-exchanged water was added to the collected organic layer and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out the organic layer. This washing operation was repeated 8 times. After concentrating the obtained organic layer, 50 parts of tert-butyl methyl ether was added to the resulting residue and stirred, followed by filtration to obtain an acid generator represented by the formula (B1-22) 6. 84 parts were obtained.

MASS (ESI (+) Spectrum): M ⁺ 237.1
MASS (ESI (-) Spectrum): M ^- 323.0

以下、これらのモノマーを式番号に応じて「モノマー（ａ１−１−１）」等という。 Resin synthesis Monomers used in resin synthesis are shown below.

Hereinafter, these monomers are referred to as “monomer (a1-1-1)” according to the formula number.

Synthesis Example 10: Synthesis of Resin A1-1 As monomers, monomer (a1-1-2), monomer (a1-2-3), monomer (a2-1-1), monomer (a3-1-1), monomer (I'-1) and monomer (II'-1) are used, and the molar ratio [monomer (a1-1-2): monomer (a1-2-3): monomer (a2-1-1): monomer ( a3-1-1): monomer (I′-1): monomer (II′-1)] is mixed to be 29: 22: 3: 34: 9: 3, and 1.5 mass of the total monomer amount Doubled propylene glycol monomethyl ether acetate was added to make a solution. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and these were heated at 73 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The obtained resin was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by reprecipitation operation of filtering the resin twice. Resin A1-1 (copolymer) having a molecular weight of 7.9 × 10 ³ was obtained in a yield of 85%. This resin A1-1 has the following structural units.

Synthesis Example 11: Synthesis of Resin A1-2 As monomers, monomer (a1-1-3), monomer (a1-2-3), monomer (a2-1-1), monomer (a3-1-1), monomer (I'-1) and monomer (II'-1) are used, and the molar ratio [monomer (a1-1-3): monomer (a1-2-3): monomer (a2-1-1): monomer ( a3-1-1): monomer (I′-1): monomer (II′-1)] is mixed to be 45: 6: 3: 34: 9: 3, and 1.5 mass of the total monomer amount Doubled propylene glycol monomethyl ether acetate was added to make a solution. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and these were heated at 73 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The obtained resin was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by reprecipitation operation of filtering the resin twice. Resin A1-2 (copolymer) having a molecular weight of 7.8 × 10 ³ was obtained in a yield of 65%. This resin A1-2 has the following structural units.

Synthesis Example 12 [Synthesis of Resin A1-3]
As the monomer, monomer (a1-1-3), monomer (a1-2-9), monomer (a2-1-1), monomer (a3-2-1) and monomer (II′-1) were used, The molar ratio [monomer (a1-1-3): monomer (a1-2-9): monomer (a2-1-1): monomer (a3-2-1): monomer (II′-1)] is 18. 5: 18.5: 5: 55: 3 was mixed, and 1.5 mass times propylene glycol monomethyl ether acetate of the total monomer amount was added to prepare a solution. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and these were heated at 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The obtained resin was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by reprecipitation operation of filtering the resin twice. Resin A1-3 (copolymer) having a molecular weight of 7.9 × 10 ³ was obtained in a yield of 71%. This resin A1-3 has the following structural units.

Synthesis Example 13 [Synthesis of Resin A1-4]
As the monomer, monomer (a1-1-3), monomer (a1-2-9), monomer (a2-1-1), monomer (a3-2-1) and monomer (II′-10) were used, The molar ratio [monomer (a1-1-3): monomer (a1-2-9): monomer (a2-1-1): monomer (a3-2-1): monomer (II′-10)] is 18. 5: 18.5: 5: 55: 3 was mixed, and 1.5 mass times propylene glycol monomethyl ether acetate of the total monomer amount was added to prepare a solution. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and these were heated at 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The obtained resin was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by reprecipitation operation of filtering the resin twice. Resin A1-4 (copolymer) having a molecular weight of 7.8 × 10 ³ was obtained in a yield of 73%. This resin A1-4 has the following structural units.

Synthesis example 14: Synthesis | combination of resin A2-1 The monomer (a4-1-7) was used as a monomer, and 1.5 mass times dioxane of the total monomer amount was added, and it was set as the solution. Azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the solution in an amount of 0.7 mol% and 2.1 mol%, respectively, with respect to the total monomer amount, and these were added at 75 ° C. Heated for about 5 hours. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered.
The resin thus obtained was dissolved again in dioxane, and the solution obtained by pouring the solution into a methanol / water mixed solvent was precipitated twice, and the resin was filtered twice to perform the reprecipitation operation twice. 8 × 10 ⁴ resin A2-1 was obtained with a yield of 77%. This resin A2-1 has the following structural units.

Synthesis Example 15: Synthesis of Resin A2-2 As monomer, monomer (a5-1-1) and monomer (a4-0-1) were used, and the molar ratio (monomer (a5-1-1): monomer (a4- The mixture was mixed so that 0-1)) was 75:25, and methyl isobutyl ketone 1.2 times the total monomer amount was added to obtain a solution. To this solution, 2 mol% of azobis (2,4-dimethylvaleronitrile) as an initiator was added with respect to the total amount of monomers, and heated at 70 ° C. for about 5 hours. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate a resin, and this resin was filtered to obtain a resin A2-2 (copolymer) having a weight average molecular weight of 1.7 × 10 ^4. Obtained at 87%. This resin A2-2 has the following structural units.

Synthesis Example 16 [Synthesis of Resin A2-3]
As the monomer, monomer (a5-1-1) and monomer (a4-0-12) were used, and the molar ratio (monomer (a5-1-1): monomer (a4-0-12)) was 50:50. Then, methyl isobutyl ketone 0.6 mass times the total monomer amount was added to prepare a solution. To this solution, 3 mol% of azobis (2,4-dimethylvaleronitrile) as an initiator was added based on the total amount of monomers, and heated at 70 ° C. for about 5 hours. The obtained reaction mixture was poured into a large amount of a methanol / water mixed solvent to precipitate a resin, and this resin was filtered to obtain a resin A2-3 (copolymer) having a weight average molecular weight of 1.5 × 10 ^{4 in} a yield. Obtained at 88%. This resin A2-3 has the following structural units.

Synthesis Example 17: Synthesis of Resin X1 As a monomer, monomer (a1-1-2), monomer (a2-1-1) and monomer (a3-1-1) were used, and their molar ratio [monomer (a1-1-1- 2): Monomer (a2-1-1): Monomer (a3-1-1)] is mixed at 50:25:25, and 1.5 mass times propylene glycol monomethyl ether acetate of the total monomer amount is added. In addition, a solution was obtained. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and these were heated at 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The obtained resin was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by reprecipitation operation of filtering the resin twice. Resin X1 (copolymer) having a molecular weight of 8.8 × 10 ³ was obtained in a yield of 78%. This resin X1 has the following structural units.

<Preparation of resist composition>
Each of the components shown below was dissolved in a solvent at parts by mass shown in Table 3, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

<Resin>
A1-1 to A1-4, A2-1 to A2-3, X1: Resin A1-1 to Resin A1-4, Resin A2-1 to Resin A2-3, Resin X1
<Acid generator>
I-26: Acid generator represented by formula (I-26) I-22: Acid generator represented by formula (I-22) I-18: Acid generator represented by formula (I-18) Agent I-23: Acid Generator I-57 Represented by Formula (I-23): Acid Generator I-61 Represented by Formula (I-57) I-61: Acid Represented by Formula (I-61) Generator I-65: Acid generator represented by formula (I-65) I-18-d: Acid generator represented by formula (I-18-d) B1-21: Formula (B1-21) Acid generator B1-22 represented by formula: acid generator B1-6 represented by formula (B1-22): acid generator represented by the following formula (synthesized with reference to JP 2007-224008 A)

<Compound (D)>
D1: (Tokyo Chemical Industry Co., Ltd.)

<Solvent>
Propylene glycol monomethyl ether acetate 265 parts Propylene glycol monomethyl ether 20 parts 2-heptanone 20 parts γ-butyrolactone 3.5 parts

Examples 1 to 17 and Comparative Example 1
<Immersion exposure evaluation of resist composition>
An organic antireflective coating composition (ARC-29; manufactured by Nissan Chemical Co., Ltd.) is applied to a silicon wafer and baked at 205 ° C. for 60 seconds to form an organic reflective film having a thickness of 78 nm on the wafer. A prevention film was formed. Next, on the organic antireflection film, the above resist composition was applied (spin coated) so that the film thickness after drying was 85 nm. After coating, the silicon wafer was pre-baked on a direct hot plate for 60 seconds at the temperature described in the “PB” column of Table 3 to form a composition layer. ArF excimer stepper for immersion exposure (XT: 1900 Gi; manufactured by ASML, NA = 1.35, 3/4 Annular XY polarized light) on a silicon wafer on which the composition layer is formed, and a contact hole pattern (hole pitch 90 nm) Using a mask for forming a hole diameter of 55 nm), the exposure amount was changed stepwise. Note that ultrapure water was used as the immersion medium.
After the exposure, post-exposure baking was performed for 60 seconds on the hot plate at the temperature described in the “PEB” column of Table 3. Next, the composition layer on the silicon wafer is developed by using a butyl acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a developing solution by a dynamic dispensing method at 23 ° C. for 20 seconds, thereby forming a negative resist pattern. Manufactured.

  In the resist pattern obtained after development, the exposure amount at which the hole diameter formed using the mask was 45 nm was defined as the effective sensitivity.

<Pattern shape evaluation>
The contact hole pattern manufactured with effective sensitivity was observed with a scanning electron microscope. When the top shape is close to a rectangle as shown in FIG. 1 (a), the pattern shape is evaluated as good, and when the top shape is round as shown in FIG. 1 (b). The pattern shape was evaluated as unsatisfactory. The results are shown in Table 4.

<Evaluation of mask error factor (MEF)>
In terms of effective sensitivity, a resist pattern was formed using masks having mask hole diameters (hole diameters of light transmitting portions of the mask) of 57 nm, 56 nm, 55 nm, 54 nm, and 53 nm (all hole pitches were 90 nm). The slope of the regression line when the mask hole diameter was plotted on the horizontal axis and the hole diameter of the resist pattern formed (transferred) on the substrate by exposure was plotted on the vertical axis was calculated as the MEF value.
When the MEF value is 5.5 or less, the MEF is evaluated as good.
When the MEF value exceeded 5.5, the MEF was evaluated as not good and was evaluated as x.
The results are shown in Table 4. Numerical values in parentheses indicate MEF values.

  From the above results, it can be seen that according to the resist composition of the present invention, a resist pattern can be produced with a good pattern shape and mask error factor (MEF).

  A resist pattern having a good pattern shape and mask error factor (MEF) can be formed from the resist composition of the present invention.

Claims (3)

A resist composition comprising a resin (A1) comprising a structural unit represented by formula (II) and a structural unit having an acid labile group, and an acid generator represented by formula (I) .

[In the formula (II),
R ² represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom, and X ¹ represents a single bond, —CO—O— * or —CO—NR ⁴ — *. * Represents a bond with -Ar, R ⁴ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and Ar represents a phenyl group . ]

[In the formula (I),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
L ² represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, and —CH ₂ — contained in the divalent saturated hydrocarbon group may be replaced by —O— or —CO—. The hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group.
Ring W represents an alicyclic hydrocarbon ring having 3 to 36 carbon atoms, and the methylene group contained in the alicyclic hydrocarbon ring may be replaced with an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group. The hydrogen atom contained in the alicyclic hydrocarbon ring is a hydroxy group, a saturated hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms. May be substituted.
R ^f1 and R ^f2 each independently represent a fluorine atom or a fluorinated alkyl group having 1 to 6 carbon atoms.
n represents an integer of 1 to 8.
Z ⁺ represents an organic cation.
However, the fluorine atom contained in an anion is 3-18 pieces. ] The resist composition according to claim 1, wherein X ¹ is a single bond. The resist composition according to claim 1 or 2 , further comprising a resin (A2) having a fluorine atom and not containing a structural unit having an acid labile group.

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