JP2014224991A - Resist composition and method for producing resist pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a salt used in a resist composition capable of producing a resist pattern with excellent line edge roughness (LER).SOLUTION: A resist composition contains a resin containing a structural unit having an acid-labile group, a carboxylic acid onium salt, and an acid generator represented by formula (II). [In the formula (II), Rrepresents a C1-C24 hydrocarbon group; -CH- contained in the hydrocarbon group may be substituted with -O- or -CO-; and Zrepresents an organic cation.]

Description

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

Patent Document 1 describes a resist composition containing a resin, a salt represented by the formula (B1-3), and 2,6-diisopropylaniline.

JP 2006-257078 A

  In a resist pattern formed from a resist composition containing a resin, a salt represented by the formula (B1-3), and 2,6-diisopropylaniline, CD uniformity (CDU) may not always be satisfied. there were.

［式（ＩＩ）中、
Ｒ^３は、炭素数１〜２４の炭化水素基を表し、該炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｚ^＋は、有機カチオンを表す。］
〔２〕カルボン酸オニウム塩が、式（ＩＢ）で表される塩である〔１〕記載のレジスト組成物。

［式（ＩＢ）中、
Ｒ^１及びＲ^２は、それぞれ独立に、炭素数１〜１２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^１は同一又は相異なり、ｎが２以上の場合、複数のＲ^２は同一又は相異なる。］
〔３〕式（ＩＩ）におけるＺ^＋が、式（ｂ２−５）で表されるカチオンである〔１〕又は〔２〕記載のレジスト組成物。

［式（ｂ２−５）中、Ｒ^５は、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−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。ｂは、０〜３の整数を表す。ｂが２以上のとき、複数のＲ^５は同一又は相異なる。］
〔４〕Ｒ^５が、炭素数１〜６のアルキル基である〔３〕に記載のレジスト組成物。
〔５〕（１）〔１〕〜〔４〕のいずれか一項記載のレジスト組成物を基板上に塗布する工程、
（２）塗布後の組成物を乾燥させて組成物層を形成する工程、
（３）組成物層に露光する工程、
（４）露光後の組成物層を加熱する工程及び
（５）加熱後の組成物層を現像する工程、
を含むレジストパターンの製造方法。
〔６〕式（ＩＩＡａ）で表される酸発生剤。

［式（ＩＩＡａ）中、Ｒ^４は、炭素数１〜４のアルキル基を表す。ａは、０〜３の整数を表す。Ｒ^５は、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−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。ｂは、０〜３の整数を表す。ｂが２以上のとき、複数のＲ^５は同一又は相異なる。］
〔７〕Ｒ^５が、炭素数１〜６のアルキル基である〔６〕に記載の酸発生剤。 The present invention includes the following inventions.
[1] A resist composition comprising a resin containing a structural unit having an acid labile group, a carboxylic acid onium salt, and an acid generator represented by formula (II).

[In the formula (II),
R ³ represents a hydrocarbon group having 1 to 24 carbon atoms, and —CH ₂ — contained in the hydrocarbon group may be replaced by —O— or —CO—.
Z ⁺ represents an organic cation. ]
[2] The resist composition according to [1], wherein the carboxylic acid onium salt is a salt represented by the formula (IB).

[In the formula (IB),
R ¹ and R ² are each independently a 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, an acyloxy group having 2 to 7 carbon atoms, or a carbon number. Represents 2 to 7 alkoxycarbonyl groups, nitro groups or halogen atoms.
m and n each independently represents an integer of 0 to 4, and when m is 2 or more, the plurality of R ¹ are the same or different, and when n is 2 or more, the plurality of R ² are the same or different. . ]
[3] The resist composition according to [1] or [2], wherein Z ⁺ in formula (II) is a cation represented by formula (b2-5).

[In Formula (b2-5), R ⁵ represents an alkyl group having 1 to 12 carbon atoms, and —CH ₂ — contained in the alkyl group may be replaced by —O— or —CO—. b represents an integer of 0 to 3. When b is 2 or more, the plurality of R ⁵ are the same or different. ]
[4] The resist composition according to [3], wherein R ⁵ is an alkyl group having 1 to 6 carbon atoms.
[5] (1) A step of applying the resist composition according to any one of [1] to [4] on a 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,
A method for producing a resist pattern including:
[6] An acid generator represented by the formula (IIAa).

[In Formula (IIAa), R ⁴ represents an alkyl group having 1 to 4 carbon atoms. a represents an integer of 0 to 3. R ⁵ represents an alkyl group having 1 to 12 carbon atoms, and —CH ₂ — contained in the alkyl group may be replaced by —O— or —CO—. b represents an integer of 0 to 3. When b is 2 or more, the plurality of R ⁵ are the same or different. ]
[7] The acid generator according to [6], wherein R ⁵ is an alkyl group having 1 to 6 carbon atoms.

  According to the resist composition of the present invention, a resist pattern having excellent CD uniformity (CDU) can be produced.

In the present specification, unless otherwise specified, in the description of the structural formula of a compound, “aliphatic hydrocarbon group” means a linear or branched hydrocarbon group, and “alicyclic hydrocarbon group” means A group obtained by removing a number of hydrogen atoms corresponding to the valence from the ring of an alicyclic hydrocarbon. The “aromatic hydrocarbon group” also includes a group in which a hydrocarbon group is bonded to an aromatic ring. When stereoisomers exist, all stereoisomers are included.
Further, "(meth) acrylic monomer" means at least one monomer having a structure of "CH ₂ = CH-CO-" or _{"CH 2 = C (CH 3)} -CO- ". Similarly, “(meth) acrylate” and “(meth) acrylic acid” mean “at least one of acrylate and methacrylate” and “at least one of acrylic acid and methacrylic acid”, respectively.

<Resist composition>
The resist composition of the present invention includes a resin containing a structural unit having an acid labile group (hereinafter sometimes referred to as “resin (A)”), a carboxylic acid onium salt, and an acid generator represented by the formula (II) (Hereinafter sometimes referred to as “acid generator (II)”).
The resist composition of the present invention preferably further contains a solvent (E).
The resist composition of the present invention may further contain a basic compound (C).

<Resin (A)>
The resin (A) includes a structural unit having an acid labile group (hereinafter sometimes referred to as “structural unit (a)”). Furthermore, a structural unit having no acid labile group (hereinafter sometimes referred to as “structural unit (s)”) may be included.
In this specification, the “acid-labile group” has a leaving group, and the leaving group is eliminated by contact with an acid to form a hydrophilic group (for example, a hydroxy group or a carboxy group). Means group.

［式（１）中、Ｒ^a1、Ｒ^a2及びＲ^a3は、それぞれ独立に、炭素数１〜８のアルキル基又は炭素数３〜２０の脂環式炭化水素基を表すか、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する。＊は結合手を表す。］

［式（２）中、Ｒ^ａ１’及びＲ^ａ２’は、それぞれ独立に、水素原子又は炭素数１〜１２の炭化水素基を表し、Ｒ^ａ３’は、炭素数１〜２０の炭化水素基を表すか、Ｒ^ａ２’及びＲ^ａ３’は互いに結合して炭素数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価の炭化水素基を構成するメチレン基は、酸素原子又は硫黄原子で置き換わってもよい。＊は結合手を表す。］ <Structural unit (a)>
The structural unit (a) is a structural unit having an “acid labile group” as described above. By including such a structural unit (a), the resin (A) is decomposed by the action of an acid, It preferably has a property that the solubility in butyl acetate or 2-heptanone is reduced.
Examples of the acid labile group include a group represented by the formula (1) and a group represented by the formula (2).

Wherein (1), R ^a1, R ^a2 and R ^a3 each independently represent a cycloaliphatic hydrocarbon radical of the alkyl group or 3 to 20 carbon atoms having 1 to 8 carbon atoms, R ^a1 and R ^a2 combine with each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms. * 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 ^{a2 ′} and R ^{a3 ′} are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms, and the methylene group constituting the hydrocarbon group and the divalent hydrocarbon group is An oxygen atom or a sulfur atom may be substituted. * Represents a bond. ]

アルキル基と脂環式炭化水素基とを組合わせた基としては、例えば、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, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an 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 decahydronaphthyl group, adamantyl group, norbornyl group, and the following groups (* represents a bond). The alicyclic hydrocarbon group of R ^{a1 to} R ^a3 is preferably an alicyclic hydrocarbon group having 3 to 16 carbon atoms.

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

Examples of —C (R ^a1 ) (R ^a2 ) (R ^a3 ) in the case where R ^a1 and R ^a2 are bonded to each other to form a divalent hydrocarbon group include the following groups. The divalent hydrocarbon group preferably has 3 to 12 carbon atoms. * Represents a bond with -O-.

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-alkyladamantan-2-yloxycarbonyl group (in the formula (1), R ^a1 , R ^a2 and the carbon atom to which they are bonded form an adamantyl group, and R ^a3 is an alkyl group) and 1- ( And adamantane-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 for R ^{a1 ′ to} R ^{a3 ′} include an alkyl group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group.
Examples of the alkyl group and alicyclic hydrocarbon group are the same as those described above.
Aromatic hydrocarbon groups include phenyl, naphthyl, anthryl, p-methylphenyl, p-tert-butylphenyl, p-adamantylphenyl, tolyl, xylyl, cumenyl, mesityl, biphenyl Groups, phenanthryl groups, 2,6-diethylphenyl groups, aryl groups such as 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.

  The monomer for deriving the structural unit (a) 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.

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

  As a structural unit derived from a (meth) acrylic monomer having a group represented by the formula (1), a structural unit represented by the formula (a1-0) is preferably represented by the formula (a1-1). The structural unit represented by a structural unit or a formula (a1-2) is mentioned. 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), a monomer for deriving structural unit (a1-0), a monomer for deriving structural unit (a1-1), and a structural unit (a1- The monomer that induces 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 group obtained by combining these. ]

L ^a01 is 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 the 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 10 or less carbon atoms, and 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 , R ^a03 and R ^a04 each independently ^represent an alkyl group having 1 to 8 carbon atoms, or two of R ^a02 , R ^a03 and R ^a04 each independently ^represent a carbon number It is preferable that it is a 1-8 alkyl group, and the remaining one is a C3-C18 alicyclic hydrocarbon group.
R ^a02 , R ^a03 and R ^a04 are each independently an alkyl group having 1 to 6 carbon atoms, or two of R ^a02 , R ^a03 and R ^a04 are each independently It is more preferable that it is a 1-6 alkyl group, and the remaining one is a C5-C12 alicyclic hydrocarbon group.
R ^a02 , R ^a03 and R ^a04 are each independently a methyl group, an ethyl group or a propyl group, or two of R ^a02 , R ^a03 and R ^a04 are each independently a methyl group More preferably, they are an ethyl group or a propyl group, and the remaining one is a cyclohexyl group or an adamantyl group.

The monomer for deriving the structural unit (a1-0) (hereinafter sometimes referred to as “monomer (a1-0)”) is represented by the formula (a1-0-1) to the formula (a1-0-12). And a monomer in which the methacryloyl group in the formula (a1-0-1) to the formula (a1-0-12) is replaced by an acryloyl group, the formula (a1-0-1) to the formula (a1-0- The monomer represented by 10) is preferred.

  When the resin (A) contains the structural unit (a1-0), the content is preferably 1 to 70 mol%, more preferably 3 to 65 mol, based on all the structural units of the resin (A). %.

［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合わせた基を表す。
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 obtained 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 ^a1 and L ^a2 are preferably —O— or ^* —O— (CH ₂ ) _k1 —CO—O—, more preferably —O—. k1 is preferably an integer of 1 to 4, more preferably 1.
R ^a4 and R ^a5 are preferably methyl groups.
Examples of the alkyl group of R ^a6 and R ^a7 , the alicyclic hydrocarbon group, and the group obtained by combining these include the same groups as those described for R ^{a1 to} R ^a3 in formula (1).
The alkyl group for R ^a6 and R ^a7 preferably has 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 a monomer (a1-1), the monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned, for example. Among these, a monomer represented by any one of formula (a1-1-1) to formula (a1-1-8) is preferable, and any one of formula (a1-1-1) to formula (a1-1-4) is preferable. The monomer represented by is more preferable.

Examples of the monomer (a1-2) include 1-ethylcyclopentan-1-yl (meth) acrylate, 1-ethylcyclohexane-1-yl (meth) acrylate, and 1-ethylcycloheptan-1-yl (meth). Acrylate, 1-methylcyclopentan-1-yl (meth) acrylate, 1-methylcyclohexane-1-yl (meth) acrylate, 1-isopropylcyclopentan-1-yl (meth) acrylate and 1-isopropylcyclohexane-1- Il (meth) acrylate may be mentioned. Monomers represented by formula (a1-2-1) to formula (a1-2-12) are preferred, and formula (a1-2-3) to formula (a1-2-4) and formula (a1-2-9) ) To (a1-2-10) are more preferable, and monomers represented by the formula (a1-2-3) and (a1-2-9) are more preferable.

  When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is usually 10 to 95 mol with respect to all the structural units of the resin (A). %, Preferably 15 to 90 mol%, more preferably 20 to 85 mol%.

  As a structural unit derived from a (meth) acrylic monomer having a group represented by the formula (2), a structural unit represented by the formula (a1-5) (hereinafter referred to as “structural unit (a1-5)”) There are).

［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−Ｌ^ａ１４−を表し、ｈ３は１〜４の整数を表し、＊は、Ｌ^ａ１１との結合手を表す。
Ｌ^ａ１１、Ｌ^ａ１２、Ｌ^ａ１３及びＬ^ａ１４は、それぞれ独立に、酸素原子又は硫黄原子を表す。
ｓ１は、１〜３の整数を表す。
ｓ１’は、０〜３の整数を表す。］

[In the 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 ^a14 —, h3 represents an integer of 1 to 4, and * represents a bond to L ^a11 .
L ^a11 , L ^a12 , L ^a13 and L ^a14 each independently represent an oxygen atom or a sulfur atom.
s1 represents an integer of 1 to 3.
s1 ′ represents an integer of 0 to 3. ]

Examples of the halogen atom include a fluorine atom and a chlorine atom, and a fluorine atom is preferable. Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a fluoromethyl group and a trifluoromethyl group. Groups.
In formula (a1-5), R ^a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group.
L ^a11 is preferably an oxygen atom.
One of L ^a12 and L ^a13 is preferably an oxygen atom and the other is a sulfur atom.
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—.

As a monomer (a1-5), the monomer described in Unexamined-Japanese-Patent No. 2010-61117 is mentioned, for example. Among these, monomers represented by formulas (a1-5-1) to (a1-5-4) are preferable, and monomers represented by formula (a1-5-1) or formula (a1-5-2) are preferable. Is more preferable.

  When resin (A) has a structural unit (a1-5), the content rate is preferable 1-50 mol% with respect to all the structural units of resin (A), and 3-45 mol% is more preferable. 5 to 40 mol% is more preferable.

The structural unit (a1) is preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), the structural unit (a1-2), and the structural unit (a1-5). More preferably, it is at least one selected from the group consisting of the structural unit (a1-1), the structural unit (a1-2) and the structural unit (a1-5), and more preferably the structural unit (a1). -1), structural unit (a1-2), and structural unit (a1-5), at least two selected from the group consisting of structural unit (a1-5), particularly preferably structural unit (a1-1) and structural unit (a1- 2) and / or structural unit (a1-5).
The structural unit (a1) is preferably a structural unit including the structural unit (a1-1).

<Structural unit (s)>
The monomer for deriving the “structural unit (s)” which is a structural unit having no acid labile group is not particularly limited as long as it is a monomer having no acid labile group, and a known monomer in the resist field can be used. .
As the structural unit (s), a structural unit having a hydroxy group or a lactone ring and having no acid labile group is preferable. 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 If a resin having a unit (hereinafter sometimes referred to as “structural unit (a3)”) is used for the resist composition, the resolution of the resist pattern and the adhesion to the substrate can be improved.

<Structural unit (a2)>
The hydroxy group contained in the structural unit (a2) may be an alcoholic hydroxy group or a phenolic hydroxy group.
When the resist composition is applied to KrF excimer laser exposure (248 nm), high energy beam exposure such as electron beam or EUV (extreme ultraviolet light), the structural unit (a2) having a phenolic hydroxy group as the structural unit (a2) ) Is preferably used. When applied to ArF excimer laser exposure (193 nm) or the like, the structural unit (a2) is preferably a structural unit (a2) having an alcoholic hydroxy group, and more preferably a structural unit (a2-1). As the structural unit (a2), one type may be contained alone, or two or more types may be used in combination.

［式（ａ２−１）中、
Ｌ^a3は、−Ｏ−又は^＊−Ｏ−（ＣＨ₂）_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。］ 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)”).

[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 the formula (a2-1), L ^a3 is preferably, -O -, - O- (CH 2) f1 -CO-O- and is (wherein f1 is an integer from 1 to 4), more preferably Is —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.

As a monomer which introduce | transduces structural unit (a2-1), the monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned, for example. 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.

  When resin (A) contains structural unit (a2-1), the content rate is 3 to 45 mol% normally with respect to all the structural units of resin (A), Preferably it is 1 to 40 mol%. More preferably, it is 1-35 mol%, More preferably, it is 2-30 mol%.

<Structural unit (a3)>
The lactone ring included in the structural unit (a3) may be a monocycle such as a β-propiolactone ring, γ-butyrolactone ring, or δ-valerolactone ring, and may be a monocyclic lactone ring and another ring. A condensed ring may be used. Among these lactone rings, a bridged ring containing a γ-butyrolactone ring or a γ-butyrolactone ring structure is preferable.

  The structural unit (a3) is preferably a structural unit represented by the formula (a3-1), the formula (a3-2), the formula (a3-3) or the formula (a3-4).

［式（ａ３−１）中、
Ｌ^a4は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_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は互いに同一又は相異なる。
式（ａ３−２）中、
Ｌ^a5は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_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は互いに同一又は相異なる。
式（ａ３−３）中、
Ｌ^a6は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_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は互いに同一又は相異なる。
式（ａ３−４）中、
Ｒ^a24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。
Ｌ^a7は、単結合、^＊−Ｌ^a8−Ｏ−、^＊−Ｌ^a8−ＣＯ−Ｏ−、^＊−Ｌ^a8−ＣＯ−Ｏ−Ｌ^a9−ＣＯ−Ｏ−又は^＊−Ｌ^a8−Ｏ−ＣＯ−Ｌ^a9−Ｏ−を表す。
＊は−Ｏ−との結合手を表す。
Ｌ^a8及びＬ^a9は、互いに独立に、炭素数１〜６のアルカンジイル基を表す。］

[In the formula (a3-1),
L ^a4 represents an oxygen atom or a group represented by ^* —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 are the same or different from each other.
In formula (a3-2),
L ^a5 represents an oxygen atom or a group represented by ^* —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 are the same or different from each other.
In formula (a3-3),
L ^a6 represents an oxygen atom or a group represented by ^* —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 are the same or different from each other.
In formula (a3-4),
R ^a24 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
L ^a7 is a single bond, ^* —L ^a8 —O—, ^* —L ^a8 —CO—O—, ^* —L ^a8 —CO—O—L ^a9 —CO—O— or ^* —L ^a8 —O—CO —L ^a9 —O— is represented.
* Represents a bond with -O-.
L ^a8 and L ^a9 each independently represent an alkanediyl group having 1 to 6 carbon atoms. ]

Examples of the halogen atom for R ^a24 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
^Examples of the alkyl group for R ^a24 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, and n-hexyl group. , Preferably it is a C1-C4 alkyl group, More preferably, it is a methyl group or an ethyl group.
Examples of the alkyl group having a halogen atom of R ^a24 include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluorosec-butyl group, perfluorotert-butyl group, perfluoropentyl group, perfluoro group. A hexyl group, a trichloromethyl group, a tribromomethyl group, a triiodomethyl group, etc. are mentioned.

^Examples of the alkanediyl group represented by L ^a8 and L ^a9 include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, and a pentane-1,5. -Diyl group and hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1, 4-diyl group, 2-methylbutane-1,4-diyl group, etc. are mentioned.

In the formula (a3-1) to the formula (a3-3), L ^{a4 to} L ^a6 are independently of each other preferably an oxygen atom or k- is an integer of 1 to 4 * —O— (CH ₂ ). A group represented by _{k 3} —CO—O—, more preferably an oxygen atom and * —O—CH ₂ —CO—O—, still more preferably an oxygen atom.
R ^{a18 to} R ^a21 are preferably methyl groups.
R ^a22 and R ^a23 are independently of each other preferably a carboxy group, a cyano group or a methyl group.
p1, q1 and r1 are each independently preferably an integer of 0-2.

In formula (a3-4),
R ^a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group.
L ^a7 is preferably a single bond or ^* -L ^a8 —CO—O—, and more preferably a single bond, —CH ₂ —CO—O— or —C ₂ H ₄ —CO—O—. .

  As the monomer for deriving the structural unit (a3), a monomer described in JP2010-204646A, a monomer described in JP2000-122294A, a monomer described in JP2012-41274A, For example, Formula (a3-1-1) to Formula (a3-1-6), Formula (a3-2-1) to Formula (a3-2-4), Formula (a3-3-1) to Formula (a3) -3-4) and a monomer represented by any one of formulas (a3-4-1) to (a3-4-6). Among them, the formula (a3-1-1), the formula (a3-1-2), the formula (a3-2-3), the formula (a3-2-4), the formula (a3-4-1), or the formula ( The structural unit derived from the monomer represented by a3-4-2) is more preferable, and represented by the formula (a3-1-1), the formula (a3-2-3), or the formula (a3-4-2). More preferred are structural units derived from monomers.

In the above structural unit, a compound in which a methyl group corresponding to R ^a24 is replaced with a hydrogen atom can also be given as a specific example of a monomer that leads to the structural unit (a3-4).

  Among structural units (a3), formula (a3-1-1), formula (a3-1-2), formula (a3-2-3), formula (a3-2-4), formula (a3-4-) 1) or a structural unit derived from a monomer represented by the formula (a3-4-2) is more preferable, and the formula (a3-1-1), the formula (a3-2-3) or the formula (a3-4-2) The structural unit derived from a monomer represented by

When the resin (A) includes the structural unit (a3), the total content is usually 5 to 70 mol%, preferably 10 to 65 mol%, based on all the structural units of the resin (A). More preferably, it is 10-60 mol%.
Moreover, content of a structural unit (a3-1), a structural unit (a3-2), a structural unit (a3-3), and a structural unit (a3-4) is respectively with respect to all the structural units of resin (A). 5 to 60 mol% is preferable, 5 to 50 mol% is more preferable, and 10 to 50 mol% is more preferable.

<Structural unit (a4)>
Examples of the halogen atom that the structural unit (a4) has include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Especially, it is preferable that the structural unit (a4) has a fluorine atom.

［式（ａ４−０）中、
Ｒ^５は、水素原子又はメチル基を表す。
Ｌ^２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 ² represents 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. ]

Examples of the L ³ perfluoroalkanediyl group include a difluoromethylene group, a perfluoroethylene group, a perfluoroethylfluoromethylene group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, and a perfluorobutane-1,4. -Diyl group, perfluoropentane-1,5-diyl group, perfluorohexane-1,6-diyl group, perfluoroheptane-1,7-diyl group, perfluorooctane-1,8-diyl group and the like.

L ² is preferably a methylene group or an ethylene group, and more preferably 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 following.

In the above structural unit, a structural unit in which a methyl group corresponding to R ³ is replaced by a hydrogen atom can also be given as a specific example of the structural unit (a4-0).

［式（ａ４−１）中、
Ｒ^a41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。
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、互いに独立に、置換基を有していてもよい炭素数１〜５の２価の脂肪族炭化水素基を表す。
Ａ^a43は、単結合又は置換基を有していてもよい炭素数１〜５の２価の脂肪族炭化水素基を表す。
Ｘ^a41及びＸ^a42は、互いに独立に、−Ｏ−、−ＣＯ−、−ＣＯ−Ｏ−又は−Ｏ−ＣＯ−を表す。
ただし、Ａ^a42、Ａ^a43及びＡ^a44の炭素数の合計は７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の炭化水素基を表し、該炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
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 C 1-6 alkyl group which may have a halogen atom, a hydrogen atom or a halogen atom.
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 a ^C 1-5 divalent aliphatic hydrocarbon group which may have a substituent.
A ^a43 represents a ^C1-C5 divalent aliphatic hydrocarbon group which may have a single bond or a substituent.
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 and A ^a44 is 7 or less. ]
Represents a group represented by
R ^a42 represents an ^optionally substituted hydrocarbon group having 1 to 20 carbon atoms, and the methylene group contained in the hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
However, at least one of A ^a41 and R ^a42 is a group having a halogen atom. ]

脂肪族炭化水素基と脂環式炭化水素基とを組み合わせた基としては、例えば、シクロプロピルメチル基、シクロブチルメチル基、アダマンチルメチル基、ノルボルニルメチル基等が挙げられる。
芳香族炭化水素基としては、例えば、フェニル基、トリル基、キシリル基、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、フルオレニル基等が挙げられる。 R ^a41 includes the same group as R ^a24 in formula (a3-4). Of these, R ^a41 is preferably a hydrogen atom or a methyl group.
^Examples of the hydrocarbon group for R ^a42 include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group obtained by combining these. The aliphatic hydrocarbon group may have a carbon-carbon unsaturated bond, but is preferably an aliphatic saturated hydrocarbon group. Similarly, the alicyclic hydrocarbon group is an alicyclic saturated hydrocarbon group. preferable.
Examples of the aliphatic hydrocarbon group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, hexadecyl group, pentadecyl group, hexyl. Examples include alkyl groups such as decyl group, heptadecyl group, and octadecyl group.
Examples of the alicyclic aliphatic hydrocarbon group include a cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* Represents a bond.) And a polycyclic alicyclic hydrocarbon group.

Examples of the group obtained by combining an aliphatic hydrocarbon group and an alicyclic hydrocarbon group include a cyclopropylmethyl group, a cyclobutylmethyl group, an adamantylmethyl group, and a norbornylmethyl group.
Examples of the aromatic hydrocarbon group include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, an anthryl group, a biphenylyl group, a phenanthryl group, and a fluorenyl group.

^As the hydrocarbon group for R ^a42 , an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or a group obtained by combining these is preferable, and an aliphatic saturated hydrocarbon group, an alicyclic saturated hydrocarbon group, or a combination thereof. Groups are more preferred.

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 hydrocarbon group having a halogen atom is preferably a hydrocarbon group having a fluorine atom, more preferably an aliphatic hydrocarbon group having a fluorine atom, an alicyclic hydrocarbon group having a fluorine atom, or a combination thereof. It is a group.

Examples of the aliphatic hydrocarbon 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, 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, perfluorobutyl, 1,1-bis (trifluoro) methyl-2,2,2-trifluoroethyl, 2- (perfluoro Olopropyl) ethyl group, 1,1,2,2,3,3,4,4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3,4,4,5,5- Decafluoropentyl group, 1,1-bis (trifluoromethyl) -2,2,3,3,3-pentafluoropropyl group, 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, perfluoropentyl Fluorinated alkyl groups such as a methyl group, a perfluorohexyl group, a perfluoroheptyl group, and a perfluorooctyl group are exemplified, and among them, a perfluoroalkyl group is preferable.
Examples of the alicyclic hydrocarbon group having a fluorine atom include a perfluorocycloalkyl group such as a perfluorocyclohexyl group; a perfluoroadamantyl group.
The hydrocarbon group having a halogen atom preferably has 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms.
Examples of the group having a fluorine atom in which an aliphatic hydrocarbon group and an alicyclic hydrocarbon group are combined include a perfluoroadamantylmethyl group.

^Examples of the substituent that the hydrocarbon group of R ^a42 may have include a halogen atom, —O—R ^h1 , —CO—R ^h2 , —O—CO—R ^h3 and —CO—O—R ^h4. Can be mentioned.
R ^{h1 to} R ^h4 each independently represent a hydrocarbon group optionally having a halogen atom having 1 to 18 carbon atoms. However, the ^sum of the carbon number of the hydrocarbon group of R ^a42 , the carbon number of the substituent, and the number of —O— and —CO— contained in the substituent is 20 or less, preferably 15 or less. More preferably, it is 12 or less.

When R ^a42 is a group having a halogen atom, the hydrocarbon group of R ^a42 is, as a substituent, a halogen atom, —O—R ^h1 , —CO—R ^h2 , —O—CO—R ^h3 and —CO—. It is preferable to have at least one selected from the group consisting of O—R ^h4 .
^When the hydrocarbon group of R ^a42 has —O—R ^h1 , —CO—R ^h2 , —O—CO—R ^h3 or —CO—O—R ^h4 , the number is preferably one.
R ^{h1 to} R ^h4 each independently represent a hydrocarbon group having a halogen atom having 1 to 18 carbon atoms. However, the ^sum of the carbon number of the hydrocarbon group of R ^a42 , the carbon number of the substituent, and the number of —O— and —CO— contained in the substituent is 20 or less, preferably 15 or less. More preferably, it is 12 or less.
The hydrocarbon group of R ^{h1 to} R ^h4 is preferably an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or a group obtained by combining these. The hydrocarbon group having a halogen atom is preferably a hydrocarbon group having a fluorine atom, more preferably an aliphatic hydrocarbon group having a fluorine atom, an alicyclic hydrocarbon group having a fluorine atom, or a combination thereof. Specific examples thereof include the above-described groups.

［式（ａ−ｇ２）中、
Ａ^a46は、ハロゲン原子を有していてもよい炭素数１〜１７の２価の炭化水素基を表す。
Ｘ^a44は、カルボニルオキシ基又はオキシカルボニル基を表す。
Ａ^a47は、ハロゲン原子を有していてもよい炭素数１〜１７の１価の炭化水素基を表す。
ただし、Ａ^a46及びＡ^a47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。］ When R ^a42 is a group having a halogen atom, R ^a42 is preferably a group represented by the formula (a-g2).

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

Of A ^a46 and A ^a47 , both may be a group having a halogen atom, but A ^a46 is preferably a group having a halogen atom.
A ^a46 is preferably a divalent aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom, or a divalent alicyclic group having 3 to 17 carbon atoms which may have a halogen atom. Or a divalent group having 4 to 17 carbon atoms, or a combination thereof, more preferably a divalent aliphatic hydrocarbon group having 1 to 6 carbon atoms which may have a halogen atom. More preferably, it is a C 1-3 divalent aliphatic hydrocarbon group which may have a halogen atom. In particular,
A ^a47 is preferably a monovalent aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom, or a monovalent alicyclic group having 3 to 17 carbon atoms which may have a halogen atom. A monovalent group having 4 to 17 carbon atoms or a combination thereof, more preferably a monovalent aliphatic hydrocarbon group having 1 to 15 carbon atoms which may have a halogen atom, halogen A monovalent alicyclic hydrocarbon group having 3 to 15 carbon atoms which may have atoms, or a monovalent group having 4 to 15 carbon atoms in combination thereof, more preferably a halogen atom. And a monovalent alicyclic hydrocarbon group having 5 to 12 carbon atoms.
A ^a47 is particularly preferably a cyclohexyl group or an adamantyl group.

Examples of the group represented by the formula (a-g2) include the following structures.

^As the alkanediyl group of ^Aa41 , 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.
^Examples of the substituent in the alkanediyl group of A ^a41 include a halogen atom, 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 alkanediyl groups such as 1,4-diyl group, 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, and 2-methylpropane-1,2-diyl group. . Examples of these substituents include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms.
s is preferably 0.

^Examples of the group (a-g1) in which X ^a42 is an oxygen atom include the following groups. In the following examples, * is a bond with —O—CO—R ^a42 .

Examples of the group (a-g1) in which X ^a42 is a carbonyl group include the following groups.

Examples of the group (a-g1) in which X ^a42 is a carbonyloxy group include the following groups.

Examples of the group (a-g1) in which X ^a42 is an oxycarbonyl group include the following groups.

［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), a structural unit represented by the formula (a4-2) or the formula (a4-3) is 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 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, 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 for R ^f2 includes an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group obtained by combining these. The aliphatic hydrocarbon group is preferably an aliphatic saturated hydrocarbon group, and the alicyclic hydrocarbon group is preferably an alicyclic saturated hydrocarbon group. As the hydrocarbon group for R ^f2, the same groups as the hydrocarbon groups for R ^a42 in formula (a4-1) can be mentioned.

Examples of the hydrocarbon group having a fluorine atom of R ^f2 include the same groups as the aliphatic hydrocarbon group having a fluorine atom and the alicyclic hydrocarbon group having a fluorine atom, which are mentioned as the group representing R ^a42 .

In formula (a4-2), as A ^f1 , an alkanediyl group having 2 to 4 carbon atoms is preferable, and an ethylene group is more preferable.
R ^f2 is preferably a C 1-10 aliphatic hydrocarbon group having a fluorine atom or a C 3-10 alicyclic hydrocarbon group having a fluorine atom, and a C 1-6 fluorinated alkyl group. Is more preferable.

［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１〜１７の２価の脂肪族炭化水素基、フッ素原子を有していてもよい炭素数３〜１７の２価の脂環式炭化水素基又はこれらを組み合わせた２価の基を表す。
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、フッ素原子を有していてもよい炭素数３〜１７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。
ただし、Ａ^ｆ13及びＡ^ｆ14のうち少なくとも一方は、フッ素原子を有する基を表す。］

[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 is a divalent aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom, or a divalent alicyclic carbon group having 3 to 17 carbon atoms which may have a fluorine atom. A hydrogen group or a divalent group in which these are combined is represented.
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, an alicyclic hydrocarbon group having 3 to 17 carbon atoms which may have a fluorine atom, or a combination thereof. Represents a group.
However, at least one of A ^f13 and A ^f14 represents a group having a fluorine atom. ]

^Examples of the alkanediyl group for A ^f11 include the same groups as the alkanediyl group for A ^f1 , and an ethylene group is preferable.

As the divalent aliphatic hydrocarbon group which may have a fluorine atom of A ^{f13 and} the divalent alicyclic hydrocarbon group which may have a fluorine atom, the same groups as those in R ^a42 may be used. And a group in which one hydrogen atom or fluorine atom has been removed.
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 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 group, perfluoro Examples thereof include perfluoroalkanediyl groups such as propanediyl group, perfluorobutanediyl group and perfluoropentanediyl group.
The divalent alicyclic hydrocarbon group which may have a fluorine atom may be monocyclic or polycyclic. Examples of the monocyclic alicyclic 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.
The divalent group formed by combining the divalent aliphatic hydrocarbon group which may have a fluorine atom and the divalent alicyclic hydrocarbon group which may have a fluorine atom has a total carbon number of 17 It is as follows.
A ^f13 is preferably a C 1-6 divalent aliphatic hydrocarbon group which may have a fluorine atom, or a C 3-6 divalent fat which may have a fluorine atom. A cyclic hydrocarbon group or a divalent group having 4 to 6 carbon atoms, or a combination thereof, more preferably a divalent aliphatic hydrocarbon group having 1 to 6 carbon atoms which may have a fluorine atom. More preferably, it is a C2-C3 bivalent aliphatic hydrocarbon group which may have a fluorine atom.

As the aliphatic hydrocarbon group which may have a fluorine atom of A ^{f14 and} the alicyclic hydrocarbon group which may have a fluorine atom, the same groups as those in R ^a42 may be mentioned. The aliphatic hydrocarbon group which may have a fluorine atom is preferably an aliphatic saturated hydrocarbon group which may have a fluorine atom, and the alicyclic hydrocarbon group which may have a fluorine atom is An alicyclic saturated hydrocarbon group which may have a fluorine atom is preferred. The group combining the aliphatic hydrocarbon group which may have a fluorine atom and the alicyclic hydrocarbon group which may have a fluorine atom has a total carbon number of 17 or less.
A ^f14 is preferably an aliphatic hydrocarbon group having 1 to 12 carbon atoms which may have a fluorine atom, an alicyclic hydrocarbon group having 3 to 12 carbon atoms which may have a fluorine atom, or C4-12 group which combined these, More preferably, C1-C10 aliphatic hydrocarbon group, C3-C10 alicyclic hydrocarbon group, or carbon number 4 which combined these -12 groups, more preferably an alicyclic hydrocarbon group having 3 to 10 carbon atoms, or a group having 4 to 10 carbon atoms in which an aliphatic hydrocarbon group and an alicyclic hydrocarbon group are combined. . A ^f14 is particularly preferably a cyclopropylmethyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group or an adamantyl group.

At least one of A ^f13 and A ^f14 is a group having a fluorine atom, and preferably A ^f13 is a group having a fluorine atom.

Examples of the structural unit represented by formula (a4-2) include structural units represented by formula (a4-1-1) to formula (a4-1-22), respectively.

Examples of the structural unit represented by formula (a4-3) include structural units represented by formula (a4-1′-1) to formula (a4-1′-22), respectively.

［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、互いに独立に、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 represent 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).

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.
R ^f22 is preferably a ^C 1-10 aliphatic hydrocarbon group having a fluorine atom or a C 1-10 alicyclic hydrocarbon group having a fluorine atom, and a C 1-10 aliphatic having a fluorine atom. An aromatic saturated hydrocarbon group is more preferable, and an aliphatic saturated hydrocarbon group having 1 to 6 carbon atoms having a fluorine atom is more preferable.

As a structural unit represented by Formula (a4-4), the structural unit represented by the following is mentioned, for example.

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

<Other structural units (t)>
Examples of the structural unit (t) include the structural unit (a2), the structural unit (a3), and the structural unit (s) having a non-leaving hydrocarbon group in addition to the structural unit (a4) (hereinafter referred to as “structural unit (a5)”). In some cases).

［式（ａ５−１）中、
Ｒ⁵¹は、水素原子又はメチル基を表す。
Ｒ⁵²は、炭素数３〜１８の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれる水素原子は炭素数１〜８の脂肪族炭化水素基又はヒドロキシ基で置換されていてもよい。但し、Ｌ⁵¹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。
Ｌ⁵¹は、単結合又は炭素数１〜１８の２価の飽和炭化水素基を表し、該飽和炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。］ <Structural unit (a5)>
Examples of 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) is 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 bonding position with 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 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, and 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. .
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^x1及びＬ^x2の合計炭素数は、１７以下である。
式（Ｌ１−３）中、
Ｌ^x5は、炭素数１〜１５の２価の脂肪族飽和炭化水素基を表す。
Ｌ^x6及びＬ^x７は、それぞれ独立に、単結合又は炭素数１〜１４の２価の脂肪族飽和炭化水素基を表す。
ただし、Ｌ^x5、Ｌ^x6及びＬ^x7の合計炭素数は、１５以下である。
式（Ｌ１−４）中、
Ｌ^x8及びＬ^x9は、単結合又は炭素数１〜１２の２価の脂肪族飽和炭化水素基を表す。
Ｗ^x1は、炭素数３〜１５の２価の脂環式飽和炭化水素基を表す。
ただし、Ｌ^x8、Ｌ^x9及びＷ^x1の合計炭素数は、１５以下である。 Examples of the 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 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 ^x1 and L ^x2 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 , L ^x6 and 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 carbon number of L ^x8 , L ^x9 and W ^x1 is 15 or less.

L ^x1 is preferably a C 1-8 divalent aliphatic saturated hydrocarbon group, more preferably a methylene group or an ethylene group.
L ^x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond.
L ^x3 is preferably a C 1-8 divalent aliphatic saturated hydrocarbon group.
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, 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, 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, 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.

In the above structural unit, a structural unit in which a methyl group corresponding to R ⁵¹ is replaced with a hydrogen atom can also be given as a specific example of the structural unit (a5-1).

The content of the structural unit (a) in the resin (A) is preferably 1 to 100 mol%, more preferably 10 to 95 mol%, and more preferably 15 to 90 mol% with respect to all the structural units of the resin (A). Further preferred is 20 to 85 mol%.
Resin (A) which has structural unit (a) with such a content rate can be manufactured by adjusting the use molar amount of the monomer with respect to the total molar amount of all the monomers used at the time of resin (A) manufacture.

In the case where the resin (A) is a resin composed of the structural unit (a) and the structural unit (s), these content rates are respectively based on the total structural units of the resin (A),
Structural unit (a); 10-95 mol%
Structural unit (s); 5 to 90 mol% is preferable,
Structural unit (a); 15-90 mol%
Structural unit (s); 10 to 85 mol% is more preferable,
Structural unit (a); 20 to 85 mol%
Structural unit (s); 15 to 80 mol% is more preferable.

  The resin (A) preferably contains 15 mol% or more of structural units derived from the monomer having an adamantyl group (particularly the structural unit (a1-1)) with respect to the total structural units (a). When the content of the structural unit having an adamantyl group is large, the dry etching resistance of the resist pattern is improved.

The resin (A) is preferably a resin composed of the structural unit (a) and the structural unit (s).
The structural unit (a) 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 the structural unit (a2-1). The structural unit (a3) is preferably at least one of the structural unit (a3-1) and the structural unit (a3-2).

Each structural unit constituting the resin (A) 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 weight average molecular weight of the resin (A) is preferably 2,500 or more (more preferably 3,000 or more, more preferably 4,000 or more), 50,000 or less (more preferably 30,000 or less, and further preferably 15,000 or less).

<Resin other than resin (A)>
The resist composition of the present invention includes a resin other than the above-described resin (A), for example, a resin having at least one selected from structural units (s) and structural units derived from known monomers used in the field. Etc. may be contained.

Especially, as resin other than resin (A), resin (henceforth "resin (X)") which has structural unit (a4) is preferable. In the resin (X), the content ratio of the structural unit (a4) is preferably 80 mol% or more, more preferably 85 mol% or more, and still more preferably 90 mol% or more with respect to all the structural units of the resin (X). .
Examples of the structural unit that the resin (X) may further include include a structural unit derived from the structural unit (a3) and other known monomers in the structural unit (a2).
The weight average molecular weight of the resin (X) is preferably 8,000 or more (more preferably 10,000 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 (X) is the same as that for the resin (A).

  When the resist composition of this invention contains resin other than resin (A), the content rate is 0.1-50 mass% normally with respect to the total amount of resin contained in the resist composition of this invention. , Preferably it is 0.5-30 mass%, More preferably, it is 1-20 mass%.

  In the resist composition of the present invention, the total content of the resin [resin (A) and resin other than the resin (A)] is preferably 80% by mass or more and 99.9% by mass or less in the solid content of the resist composition. It is. In the present specification, the “solid content in the composition” means the total of resist composition components excluding the solvent (E) described later. The solid content in the composition and the resin content relative thereto can be measured by known analytical means such as liquid chromatography or gas chromatography, for example.

［式（ＩＩ）中、
Ｒ^３は、置換基を有していてもよい炭素数１〜２４の炭化水素基を表し、該炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｚ^＋は、有機カチオンを表す。］ <Acid generator (II)>
The acid generator (II) is represented by the formula (II).

[In the formula (II),
R ³ represents an optionally substituted hydrocarbon group having 1 to 24 carbon atoms, and —CH ₂ — contained in the hydrocarbon group may be replaced by —O— or —CO—. Good.
Z ⁺ represents an organic cation. ]

The hydrocarbon group for R ³ may be either saturated or unsaturated, for example, a linear or branched alkyl group or alkenyl group, a monocyclic or polycyclic alicyclic hydrocarbon group, aromatic A hydrocarbon group etc. are mentioned, What combined 2 or more types among these groups may be sufficient.
Examples of the linear alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group.
Examples of the branched alkyl group include an isopropyl group, a sec-butyl group, and a tert-butyl group.
Examples of the linear or branched alkenyl group include a vinyl group and an α-methylvinyl group.
Examples of the monocyclic alicyclic hydrocarbon group include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.
Examples of the polycyclic alicyclic hydrocarbon group include a norbornyl group and an adamantyl group.
Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, 2,6-diethylphenyl group, 2- And methyl-6-ethylphenyl.

Examples of the group in which the methylene group constituting the hydrocarbon group is replaced with an oxygen atom or a carbonyl group include an alkoxyalkyl group, an acyl group, an acyloxy group, an acyloxyalkyl group, or a group represented by the following.

Examples of the alkoxyalkyl group include a methoxymethyl group and an ethoxyethyl group.
Examples of the acyl group include an acetyl group and a propionyl group.
Examples of the acyloxy group include an acetyloxy group and a propionyloxy group.
Examples of the acyloxyalkyl group include an acetyloxymethyl group and a propionyloxyethyl group.

Examples of the substituent that the hydrocarbon group of R ³ may have include a hydroxy group and a cyano group.

R ³ preferably represents an optionally substituted hydrocarbon group having 5 to 18 carbon atoms, and the methylene group contained in the hydrocarbon group may be replaced with an oxygen atom or a carbonyl group. More preferably, it represents a hydrocarbon group having 6 to 12 carbon atoms which may have a substituent, and the hydrocarbon group has an alicyclic hydrocarbon structure, and is a methylene group contained in the hydrocarbon group May be replaced by an oxygen atom or a carbonyl group.

Examples of the organic cation of 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 a cation represented by any one of the formulas (b2-1) to (b2-4) [hereinafter referred to as “cation (b2-1) according to the formula number” And so on. ] Is more preferable.

In formula (b2-1) to formula (b2-4),
R ^{b4 to} R ^b6 each independently represents an alkyl group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, or R ^b4 And R ^b5 together form a ring containing a sulfur atom. The hydrogen atom contained in the alkyl group is substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. The hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an alkyl group having 1 to 18 carbon atoms, an acyl group having 2 to 4 carbon atoms, or a glycidyloxy group. 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 ^b7 and R ^b8 each independently represent a hydroxy group, an alkyl 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 are the same or different from each other, and when n2 is 2 or more, the plurality of R ^b8 are the same or different from each other.
R ^b9 and R ^b10 each independently represent an alkyl group having 1 to 18 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or R ^b9 and R ^b10 are A 3-membered to 12-membered ring (preferably a 3-membered to 7-membered ring) is formed together with the sulfur atom to be bonded. —CH ₂ — constituting the ring may be replaced with —O—, —SO— or —CO—.
R ^b11 represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.
R ^b12 represents an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. The hydrogen atom contained in the alkyl group 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. Alternatively, it may be substituted with an alkylcarbonyloxy group having 1 to 12 carbon atoms.
R ^b11 and R ^b12 may form a 3- to 12-membered ring (preferably a 3- to 7-membered ring) together with —CH—CO— to which they are bonded. —CH ₂ — constituting the ring may be replaced with —O—, —SO— or —CO—.
R ^{b13 to} R ^b18 each independently represent a hydroxy group, an alkyl 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, the plurality of R ^b13 are the same or different from each other. When p2 is 2 or more, the plurality of R ^b14 are the same or different from each other. When q2 is 2 or more, the plurality of R ^b15 are the same. Alternatively, when r2 is 2 or more, a plurality of R ^b16 are the same or different from each other, when s2 is 2 or more, a plurality of R ^b17 are the same or different from each other, and when t2 is 2 or more, a plurality of R ^{b16 b18} are the same or different from each other.

R ^b4 and R ^b5 may together form a 3- to 12-membered ring (preferably a 3- to 7-membered ring) with the sulfur atom to which they are bonded.

特に、Ｒ^b9〜Ｒ^b11の脂環式炭化水素基は、好ましくは炭素数４〜１２である。 Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. Can be mentioned. In particular, the alkyl group of R ^{b9 to} R ^b12 preferably has 1 to 12 carbon atoms.
Examples of the alkyl group in which a hydrogen atom is substituted with an alicyclic hydrocarbon group include a 1- (adamantan-1-yl) alkane-1-yl group.
The alicyclic hydrocarbon group may be monocyclic or polycyclic, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with an alkyl group. In this case, the carbon number of the alicyclic hydrocarbon group is 20 or less including the carbon number of the alkyl group. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a 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 ^b11 preferably has 4 to 12 carbon atoms.

  Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an alkyl group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-alkyladamantan-2-yl group, a methylnorbornyl group, and an isobornyl group. Can be mentioned.

Examples of the aromatic hydrocarbon group include phenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 4-ethylphenyl group, 4-tert-butylphenyl group, 4-cyclohexylphenyl group, 4-adamantyl group. Substituted or unsubstituted phenyl groups such as phenyl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group; biphenylyl group, naphthyl group, phenanthryl group and the like.
As an aromatic hydrocarbon group by which the hydrogen atom was substituted by the alkoxy group, 4-methoxyphenyl group etc. are mentioned, for example.
Examples of the alkyl group in which a hydrogen atom is substituted with an aromatic hydrocarbon group, that is, an aralkyl group, include a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group.
In addition, when an alkyl group or an alicyclic hydrocarbon group is contained in an aromatic hydrocarbon group, a C1-C12 alkyl group and a C3-C18 alicyclic hydrocarbon group are preferable.

Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy group.
Examples of the acyl group include an acetyl group, a propionyl group, and a 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 methylcarbonyloxy group, ethylcarbonyloxy group, n-propylcarbonyloxy group, isopropylcarbonyloxy group, n-butylcarbonyloxy group, sec-butylcarbonyloxy group, tert-butylcarbonyloxy group. Group, pentylcarbonyloxy group, hexylcarbonyloxy group, octylcarbonyloxy group, 2-ethylhexylcarbonyloxy group and the like.

The ring containing a sulfur atom which may be formed by combining R ^b4 and R ^b5 is any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. If it contains one or more sulfur atoms, it may further contain one or more sulfur atoms and / or one or more oxygen atoms. As the ring, a ring having 3 to 18 carbon atoms is preferable, and a ring having 4 to 18 carbon atoms is more preferable.

Examples of the ring formed together with the sulfur atom to which R ^b9 and R ^b10 are bonded include, for example, a thiolane-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, and a 1,4-oxathian-4-ium. A ring etc. are mentioned.
Examples of the ring formed with —CH—CO— in which R ^b11 and R ^b12 are bonded include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

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.

［式（ｂ２−５）中、Ｒ^５は、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−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。ｂは、０〜３の整数を表す。ｂが２以上のとき、複数のＲ^５は同一又は相異なる。］
Ｒ^５のアルキル基としては、例えば、メチル基、エチル基、プロピル基、イソプロピル基、ブチル基、ｔｅｒｔ−ブチル基、ｎ−ヘプチル基、２−エチルヘキシル基、ｎ−オクチル基、ｎ−ノニル基、ｎ−デシル基、ｎ−ウンデシル基、ｎ−ドデシル基等が挙げられ、なかでも、炭素数１〜６のアルキル基が好ましく、メチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｔｅｒｔ−ブチル基がより好ましく、メチル基、エチル基、イソプロピル基、ｔｅｒｔ−ブチル基がさらに好ましく、メチル基、ｔｅｒｔ−ブチル基がさらにより好ましい。
アルキル基に含まれる−ＣＨ_２−が、−Ｏ−又は−ＣＯ−に置き換わった基としては、メトキシ基、エトキシ基、ブトキシ基、ヘキシルオキシ基、メトキシエチル基、エトキシエチル基、エトキシエトキシ基、エトキシエトキシエトキシ基、エトキシエトキシエトキシエトキシ基、エトキシエトキシエトキシエトキシエトキシ基、アセチル基、メトキシカルボニル基、アセチルオキシ基、ブトキシカルボニルオキシ基等が挙げられる。 Z ⁺ is preferably a cation represented by the formula (b2-5).

[In Formula (b2-5), R ⁵ represents an alkyl group having 1 to 12 carbon atoms, and —CH ₂ — contained in the alkyl group may be replaced by —O— or —CO—. b represents an integer of 0 to 3. When b is 2 or more, the plurality of R ⁵ are the same or different. ]
Examples of the alkyl group for R ⁵ include methyl group, ethyl group, propyl group, isopropyl group, butyl group, tert-butyl group, n-heptyl group, 2-ethylhexyl group, n-octyl group, n-nonyl group, An n-decyl group, an n-undecyl group, an n-dodecyl group, and the like can be mentioned. Among them, an alkyl group having 1 to 6 carbon atoms is preferable, and a methyl group, an ethyl group, an n-propyl group, an isopropyl group, tert-butyl. A group is more preferable, a methyl group, an ethyl group, an isopropyl group, and a tert-butyl group are more preferable, and a methyl group and a tert-butyl group are still more preferable.
Examples of the group in which —CH ₂ — contained in the alkyl group is replaced by —O— or —CO— include a methoxy group, an ethoxy group, a butoxy group, a hexyloxy group, a methoxyethyl group, an ethoxyethyl group, an ethoxyethoxy group, Examples include ethoxyethoxyethoxy group, ethoxyethoxyethoxyethoxy group, ethoxyethoxyethoxyethoxyethoxy group, acetyl group, methoxycarbonyl group, acetyloxy group, butoxycarbonyloxy group and the like.

Examples of the cation represented by the formula (b2-5) include the following cations.

［式（ＩＩＡ）中、Ｒ^４は、炭素数１〜４のアルキル基を表す。
ａは、０〜３の整数を表す。
Ｚ^＋は、上記と同じ意味を表す。］
Ｒ^４は、メチル基が好ましい。 Among them, the acid generator (II) is preferably an acid generator represented by the formula (IIA).

[In Formula (IIA), R ⁴ represents an alkyl group having 1 to 4 carbon atoms.
a represents an integer of 0 to 3.
Z ⁺ represents the same meaning as described above. ]
R ⁴ is preferably a methyl group.

［式（ＩＩＡａ）中、Ｚ^＋は、Ｒ^５は、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−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。ｂは、０〜３の整数を表す。ｂが２以上のとき、複数のＲ^５は同一又は相異なる。Ｒ^４は、上記と同じ意味を表す。］

［式（ＩＩＡｂ）中、Ｒ^５及びｂは、上記と同じ意味を表す。］ The acid generator represented by the formula (IIA) is preferably an acid generator represented by the formula (IIAa), and particularly preferably an acid generator represented by the formula (IIAb).

Wherein (IIAa), ^{Z +, R 5} is an alkyl group having 1 to 12 carbon atoms, -CH ₂ contained in the alkyl group - is also be replaced by -O- or -CO- Good. b represents an integer of 0 to 3. When b is 2 or more, the plurality of R ⁵ are the same or different. R ⁴ represents the same meaning as described above. ]

[In Formula (IIAb), R ⁵ and b represent the same meaning as described above. ]

Especially, the following are mentioned as preferable acid generator (II).

  The acid generator (II) can be produced, for example, by the method described in WO2011 / 104127 pamphlet.

溶剤としては、クロロホルム、イオン交換水等が挙げられる。
式（ＩＩＢ−ｂ）で表される塩は、ＷＯ２０１１／１０４１２７号パンフレットに記載された方法によって製造することができる。 Among these, the acid generator (IIB) can be produced by reacting a salt represented by the formula (IIB-a) and a salt represented by the formula (IIB-b) in a solvent. The sign in each formula represents the same meaning as above.

Examples of the solvent include chloroform and ion exchange water.
The salt represented by the formula (IIB-b) can be produced by a method described in WO2011 / 104127 pamphlet.

触媒としては、酢酸銅（ＩＩ）等が挙げられる。
溶剤としては、クロロホルム等が挙げられる。
式（ＩＩＢ−ｃ）で表される塩は、例えば、下記式で表される塩等が挙げられ、市場から容易に入手できる。

The salt represented by the formula (IIB-a) is produced by reacting the salt represented by the formula (IIB-c) and the salt represented by the formula (IIB-d) in the presence of a catalyst in a solvent. can do.

Examples of the catalyst include copper (II) acetate.
Examples of the solvent include chloroform.
Examples of the salt represented by the formula (IIB-c) include a salt represented by the following formula, and are easily available from the market.

Ｘは、塩素原子、臭素原子又はヨウ素原子を表す。
溶剤としては、クロロホルム等が挙げられる。 The salt represented by the formula (IIB-c) is produced by reacting the salt represented by the formula (IIB-e) with the compound represented by the formula (IIB-f) in a solvent. be able to.

X represents a chlorine atom, a bromine atom or an iodine atom.
Examples of the solvent include chloroform.

Examples of the salt represented by the formula (IIB-e) include a salt represented by the following formula, and these can be easily obtained from the market.

  The acid generator (II) may be used alone or in combination of two or more.

<Acid generator other than acid generator (II)>
The resist composition may contain an acid generator other than the acid generator (II) described above (hereinafter sometimes referred to as “acid generator (B)”).
The acid generator (B) may be either nonionic or ionic. 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.

  Examples of the acid generator (B) include JP-A 63-26653, JP-A 55-164824, JP-A 62-69263, JP-A 63-146038, JP-A 63-163452, JP-A-62-153853, JP-A-63-146029, US Pat. No. 3,779,778, US Pat. No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712 The compound which generate | occur | produces an acid by the radiation as described in etc. can be used.

  The acid generator (B) is preferably a fluorine-containing acid generator, more preferably a salt represented by the formula (B1) (hereinafter sometimes referred to as “salt (B1)”).

［式（Ｂ１）中、
Ｑ^b1及びＱ^b2は、それぞれ独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｌ^b1は、単結合又は炭素数１〜１７の２価の飽和炭化水素基を表し、該飽和炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基で置き換わっていてもよい。
Ｙは、置換基を有していてもよい炭素数１〜１８のアルキル基又は置換基を有していてもよい炭素数３〜１８の脂環式炭化水素基を表し、該アルキル基及び該脂環式炭化水素基を構成するメチレン基は、酸素原子、スルホニル基又はカルボニル基に置き換わっていてもよい。
Ｚ１⁺は、有機カチオンを表す。］

[In the formula (B1),
Q ^b1 and Q ^b2 each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and the methylene group constituting the saturated hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
Y represents an alkyl group having 1 to 18 carbon atoms which may have a substituent or an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent. The methylene group constituting the alicyclic hydrocarbon group may be replaced with an oxygen atom, a sulfonyl group or a carbonyl group.
Z1 ⁺ represents an organic cation. ]

Examples of the perfluoroalkyl group for Q ^b1 and Q ^b2 include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, A perfluorohexyl group etc. are mentioned.
Q ^b1 and Q ^b2 are each independently preferably a trifluoromethyl group or a fluorine atom, more preferably a fluorine atom.

The divalent saturated hydrocarbon group of L ^{b1 includes} a divalent aliphatic saturated carbon group such as a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, etc. A hydrogen group may be mentioned, and two or more of these groups may be combined.
Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1 , 6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group , Dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1, Linear alkanediyl groups such as 17-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group and propane-2,2-diyl group;
Butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4- Branched alkanediyl groups such as diyl groups;
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 the methylene group constituting the divalent saturated hydrocarbon group of L ^b1 is replaced by an oxygen atom or a carbonyl group are represented by any of formulas (b1-1) to (b1-7). Groups. L ^b1 is preferably a group represented by any one of formulas (b1-1) to (b1-4), more preferably a group represented by formula (b1-1) or formula (b1-2). Can be mentioned. In addition, Formula (b1-1)-Formula (b1-7) have described the right and left according to Formula (B1), and among two bonds represented by *, C (Q ^b1 ) binds to (Q ^b2 )-, and binds to -Y on the right. The same applies to specific examples of the following formulas (b1-1) to (b1-7).

式（ｂ１−１）〜式（ｂ１−７）中、
Ｌ^b2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。
Ｌ^b3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。
Ｌ^b4は、炭素数１〜１３の２価の脂肪族飽和炭化水素基を表す。但しＬ^b3及びＬ^b4の合計炭素数の上限は１３である。
Ｌ^b５は、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。
Ｌ^b６は、炭素数１〜１５の２価の脂肪族飽和炭化水素基を表す。但しＬ^b5及びＬ^b6の合計炭素数の上限は１５である。
Ｌ^b７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。
Ｌ^b８は、炭素数１〜１６の２価の脂肪族飽和炭化水素基を表す。但しＬ^b７及びＬ^b８の合計炭素数の上限は１６である。
Ｌ^b9は、単結合又は炭素数１〜１３の２価の脂肪族飽和炭化水素基を表す。
Ｌ^b10は、炭素数１〜１４の２価の脂肪族飽和炭化水素基を表す。但しＬ^b9及びＬ^b10の合計炭素数の上限は１４である。
Ｌ^b11及びＬ^b12は、それぞれ独立に、単結合又は炭素数１〜１１の２価の脂肪族飽和炭化水素基を表す。
Ｌ^b13は、炭素数１〜１２の２価の脂肪族飽和炭化水素基を表す。但しＬ^b11、Ｌ^b12及びＬ^b13の合計炭素数の上限は１２である。
Ｌ^b14及びＬ^b15は、それぞれ独立に、単結合又は炭素数１〜１３の２価の脂肪族飽和炭化水素基を表す。
Ｌ^b16は、炭素数１〜１４の２価の脂肪族飽和炭化水素基を表す。但しＬ^b14、Ｌ^b15及びＬ^b16の合計炭素数の上限は１４である。

In formula (b1-1) to formula (b1-7),
L ^b2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^b3 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms.
L ^b4 represents a divalent aliphatic saturated hydrocarbon group having 1 to 13 carbon atoms. However, the upper limit of the total carbon number of L ^b3 and L ^b4 is 13.
L ^b5 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms.
L ^b6 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, the upper limit of the total carbon number of L ^b5 and L ^b6 is 15.
L ^b7 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^b8 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, the upper limit of the total carbon number of L ^b7 and L ^b8 is 16.
L ^b9 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 13 carbon atoms.
L ^b10 represents a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, the upper limit of the total carbon number of L ^b9 and L ^b10 is 14.
L ^b11 and L ^b12 each independently represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 11 carbon atoms.
L ^b13 represents a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. However, the upper limit of the total carbon number of L ^b11 , L ^b12 and L ^b13 is 12.
L ^b14 and L ^b15 each independently represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 13 carbon atoms.
L ^b16 represents a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, the upper limit of the total carbon number of L ^b14 , L ^b15 and L ^b16 is 14.

Examples of the group represented by the formula (b1-1) include the following.

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

Examples of the group represented by the formula (b1-3) include the following.

Examples of the group represented by the formula (b1-4) include the following.

Examples of the group represented by the formula (b1-5) include the following.

Examples of the group represented by the formula (b1-6) include the following.

Examples of the group represented by the formula (b1-7) include the following.

Examples of the alkyl group for Y 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, heptyl group, 2 -Alkyl groups, such as an ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, are mentioned, Preferably, a C1-C6 alkyl group is mentioned.
Examples of the alicyclic hydrocarbon group include groups represented by formulas (Y1) to (Y11).
Examples of the group in which —CH ₂ — constituting the alicyclic hydrocarbon group of Y is replaced by —O—, —SO ₂ — or —CO— are represented by formulas (Y12) to (Y26). Groups.

  Especially, it is preferably a group represented by any one of formulas (Y1) to (Y19), more preferably represented by formula (Y11), formula (Y14), formula (Y15) or formula (Y19). And more preferably a group represented by formula (Y11) or formula (Y14).

Examples of the substituent of the alkyl group in Y include a halogen atom, a hydroxy group, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, and an aromatic hydrocarbon group having 6 to 18 carbon atoms.
Examples of the substituent of the alicyclic hydrocarbon group in Y include, for example, a halogen atom, a hydroxy group, an oxo group, an alkyl group having 1 to 12 carbon atoms, a hydroxy group-containing alkyl group having 1 to 12 carbon atoms, and 3 to 3 carbon atoms. 16 alicyclic hydrocarbon groups, alkoxy groups having 1 to 12 carbon atoms, aromatic hydrocarbon groups having 6 to 18 carbon atoms, aralkyl groups having 7 to 21 carbon atoms, acyl groups having 2 to 4 carbon atoms, glycidyloxy Group or — (CH ₂ ) _j2 —O—CO—R ^b1 group (wherein R ^b1 is an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, or 6 to 6 carbon atoms). 18 represents an aromatic hydrocarbon group, and j2 represents an integer of 0 to 4.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the hydroxy group-containing alkyl group include a hydroxymethyl group and a hydroxyethyl group.
Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy group.
Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group; tolyl group, xylyl group, cumenyl group, mesityl group. , Aryl groups such as biphenyl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl, and the like.
Examples of the aralkyl group include benzyl group, phenethyl group, phenylpropyl group, naphthylmethyl group, and naphthylethyl group.
Examples of the acyl group include an acetyl group, a propionyl group, and a butyryl group.

Examples of Y include the following.

In the case where Y is an alkyl group and L ^b1 is a divalent linear or branched saturated hydrocarbon group having 1 to 17 carbon atoms, the divalent saturated hydrocarbon at the bonding position with Y. The methylene group of the group is preferably replaced with an oxygen atom or a carbonyl group. In this case, the methylene group constituting the alkyl group of Y is not replaced with an oxygen atom or a carbonyl group. The same applies when the hydrogen atom contained in the alkyl group of Y and / or the divalent linear or branched saturated hydrocarbon group of L ^b1 is substituted with a substituent.

  Y is preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, more preferably a substituent (for example, an oxo group, a hydroxy group, etc.). A good adamantyl group, more preferably an adamantyl group, a hydroxyadamantyl group or an oxoadamantyl group.

The sulfonate anion in the salt (B1) is preferably an anion represented by the formula (b1-1-1) to the formula (b1-1-9). In the following formulas, the definitions of the symbols have the same meaning as described above, and R ^b2 and R ^b3 each independently represent an alkyl group having 1 to 4 carbon atoms (preferably a methyl group).
Specific examples of the sulfonate anion in the salt (B1) include anions described in JP 2010-204646 A.

Examples of the organic cation (Z1 ⁺ ) contained in the salt (B1) include an organic onium cation, such as an organic sulfonium cation, an organic iodonium cation, an organic ammonium cation, a benzothiazolium cation, and an organic phosphonium cation. An organic sulfonium cation or an organic iodonium cation, and more preferably a cation represented by any one of the above-described formulas (b2-1) to (b2-4).

  Examples of the salt (B1) include salts represented by the formula (B1-1) to the formula (B1-20). Among them, those containing an arylsulfonium cation are preferable. Formula (B1-1), Formula (B1-2), Formula (B1-3), Formula (B1-6), Formula (B1-7), Formula (B1-11) ), Formula (B1-12), formula (B1-13), formula (B1-14), formula (B1-21), formula (B1-22), formula (B1-23), formula (B1-24) And a salt represented by the formula (B1-25) or the formula (B1-26) is more preferable.

When the resist composition contains only the acid generator (II) as the acid generator, the content of the acid generator (II) is preferably 1 part by mass or more with respect to 100 parts by mass of the resin (A) ( More preferably 3 parts by mass or more), preferably 30 parts by mass or less (more preferably 25 parts by mass or less).
When the resist composition contains the acid generator (II) and the acid generator (B), the total content of the acid generator (II) and the acid generator (B) is 100 masses of the resin (A). The amount is preferably 1 part by mass or more (more preferably 3 parts by mass or more), preferably 40 parts by mass or less (more preferably 35 parts by mass or less).
The content ratio (mass ratio) between the acid generator (II) and the acid generator (B) is, for example, 5:95 to 95: 5, preferably 10:90 to 90:10, and more preferably 15: 85-85: 15.

［式（ＩＡ）中、
Ｒ^Ａは、置換基を有していてもよい炭素数１〜３６の炭化水素基又は置換基を有していてもよい炭素数３〜３６の複素環基を表す。
Ｚ’^＋は、有機オニウムカチオンを表す。
Ｒ^ＡとＺ’^＋が一緒になって、分子内塩を形成してもよい。］ <Carboxylic acid onium salt>
The resist composition of the present invention contains a carboxylic acid onium salt. The carboxylic acid onium salt is a salt of an organic onium cation and a carboxylic acid, and may form an inner salt.
Examples of the onium salt include a sulfonium salt, an iodonium salt, an ammonium salt, a phosphonium salt, and the like, and a sulfonium salt or an iodonium salt is preferable.
Examples of the carboxylic acid onium salt include a salt represented by the formula (IA).

[In the formula (IA),
R ^A represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent or a heterocyclic group having 3 to 36 carbon atoms which may have a substituent.
Z ′ ⁺ represents an organic onium cation.
R ^A and Z ′ ⁺ may be combined to form an inner salt. ]

Examples of the hydrocarbon group for ^RA include the same groups as those represented by the formula (2).
Examples of the substituent that the hydrocarbon group may have include a halogen atom, a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, a glycidyloxy group, and an acyl group having 2 to 4 carbon atoms. Among these, a halogen atom, particularly a fluorine atom is preferable.

Examples of the heterocyclic group of ^RA include a pyrrolyl group, a furyl group, a thienyl group, an indolyl group, a benzofuryl group, and a carbazolyl group.
Examples of the substituent that the heterocyclic group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and carbon. Examples include an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, or an acyl group having 2 to 4 carbon atoms. Among these, a halogen atom, particularly a fluorine atom is preferable.

R ^A is preferably an alkyl group having 1 to 8 carbon atoms or an adamantyl group, and the hydrogen atom contained in the adamantyl group is a halogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, or an alkyl group having 1 to 12 carbon atoms. An alkoxy group, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group or an acyl group having 2 to 4 carbon atoms, and the methylene group contained in the adamantyl group is May be substituted with a carbonyl group or an oxygen atom.

For example, as the carboxylate anion, anions represented by formulas (IA-1) to (IA-18); fluoroacetic acid, difluoroacetic acid, pentafluoropropionic acid, heptafluorobutyric acid, perfluorododecanoic acid, perfluorotridecane Examples include an anion derived from an acid, perfluorocyclohexanecarboxylic acid, or 2,2-bistrifluoromethylpropionic acid.

Salts organic onium a cation Z ^'+ is a represented by the compounds represented by formula (IA), include the same cations as Z ⁺ in the acid generator (II).
Further, when the formula Z salt represented by (IA) ^'+ an acid generator and a Z ⁺ in (II) is a cation of the same kind, shape and roughness of the obtained resist pattern is a good, the CDU Is also preferable because it tends to be excellent.

Examples of the carboxylic acid onium salt in which R ^A and Z ′ ⁺ together form an inner salt include a salt represented by the formula (IB). Of the carboxylic acid onium salts, a salt represented by the formula (IB) is preferable.

［式（ＩＢ）中、
Ｒ^１及びＲ^２は、それぞれ独立に、炭素数１〜１２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^１は同一又は相異なり、ｎが２以上の場合、複数のＲ^２は同一又は相異なる。］

[In the formula (IB),
R ¹ and R ² are each independently a 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, an acyloxy group having 2 to 7 carbon atoms, or a carbon number. Represents 2 to 7 alkoxycarbonyl groups, nitro groups or halogen atoms.
m and n each independently represents an integer of 0 to 4, and when m is 2 or more, the plurality of R ¹ are the same or different, and when n is 2 or more, the plurality of R ² are the same or different. . ]

Examples of the hydrocarbon group for R ¹ and R ² include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and combinations thereof.
Examples of the 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 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.
As aromatic hydrocarbon group, 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, cumenyl group , Aryl groups such as mesityl group, biphenyl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl, and the like.
These combinations include alkyl-cycloalkyl groups, cycloalkyl-alkyl groups, aralkyl groups (eg, 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) and the like.

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 Formula (IB), R ¹ and R ² 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 4 carbon atoms. And 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 is preferable.
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 ¹ are the same or different, and when n is 2 or more, the plurality of R ² are the same or different.

Examples of the salt represented by the formula (IB) include the following compounds.

  The salt represented by the formula (IB) can be produced by the method described in “Tetrahedron Vol. 45, No. 19, p6281-6296”. A commercially available compound can be used as the salt represented by the formula (IB).

Examples of the salt represented by the formula (IA) other than the salt represented by the formula (IB) include a salt represented by the following formula.

  The content of the carboxylic acid onium salt is preferably 0.01 to 5% by mass, more preferably 0.01 to 3% by mass, and still more preferably 0.01 to 1% by mass in the solid content of the resist composition. %.

<Solvent (E)>
The content of the solvent (E) is, for example, 90% by mass or more in the resist composition, preferably 92% by mass or more, more preferably 94% by mass or more, for example 99.9% by mass or less, preferably 99% by mass or less. It is. The content rate of a solvent (E) can be measured by well-known analysis means, such as a liquid chromatography or a gas chromatography, for example.

  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 And esters such as ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone; cyclic esters such as γ-butyrolactone; A solvent may contain individually by 1 type and may contain 2 or more types.

<Basic compound (C)>
The basic compound (C) is preferably a basic nitrogen-containing organic compound, and examples thereof include amines and ammonium salts. The basic compound (C) is used as a quencher in the resist composition of the present invention. A quencher is a compound having an action of capturing an acid generated from an acid generator upon exposure. Amines include aliphatic and aromatic amines; primary amines, secondary amines and tertiary amines. The basic compound (C) is preferably a compound represented by any one of formulas (C1) to (C8), more preferably a compound represented by formula (C1), and more preferably It is a compound represented by a formula (C1-1).

［式（Ｃ１）中、Ｒ^c1、Ｒ^c2及びＲ^c3は、それぞれ独立に、水素原子、炭素数１〜６のアルキル基、炭素数５〜１０の脂環式炭化水素基又は炭素数６〜２０の芳香族炭化水素基を表し、該アルキル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、アミノ基又は炭素数１〜６のアルコキシ基で置換されていてもよく、該芳香族炭化水素基に含まれる水素原子は、炭素数１〜６のアルコキシ基で置換されていてもよい。］

[In formula (C1), R ^c1 , R ^c2 and R ^c3 each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 5 to 10 carbon atoms, or 6 to 6 carbon atoms. 20 represents an aromatic hydrocarbon group, the hydrogen atom contained in the alkyl group and the alicyclic hydrocarbon group may be substituted with a hydroxy group, an amino group or an alkoxy group having 1 to 6 carbon atoms, The hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 6 carbon atoms. ]

［式（Ｃ１−１）中、Ｒ^c2及びＲ^c3は、上記と同じ意味を表す。
Ｒ^c4は、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５〜１０の脂環式炭化水素又は炭素数６〜１０の芳香族炭化水素基を表す。
ｍ３は０〜３の整数を表し、ｍ３が２以上のとき、複数のＲ^c4は同一又は相異なる。］ The compound represented by the formula (C1) is preferably a compound represented by the formula (C1-1).

[In Formula (C1-1), R ^c2 and R ^c3 represent the same meaning as described above.
R ^c4 represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alicyclic hydrocarbon having 5 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms.
m3 represents an integer of 0 to 3, and when m3 is 2 or more, the plurality of R ^c4 are the same or different. ]

［式（Ｃ２）、式（Ｃ３）及び式（Ｃ４）中、Ｒ^c5、Ｒ^c6、Ｒ^c7及びＲ^c8は、それぞれ独立に、Ｒ^c1と同じ意味を表す。
Ｒ^c9は、炭素数１〜６のアルキル基、炭素数３〜６の脂環式炭化水素基又は炭素数２〜７のアシル基を表す。
ｎ３は０〜８の整数を表し、ｎ３が２以上のとき、複数のＲ^c9は同一又は相異なる。］

[In Formula (C2), Formula (C3) and Formula (C4), R ^c5 , R ^c6 , R ^c7 and R ^c8 each independently represent the same meaning as R ^c1 .
R ^c9 represents an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 6 carbon atoms, or an acyl group having 2 to 7 carbon atoms.
n3 represents an integer of 0 to 8, and when n3 is 2 or more, the plurality of R ^c9 are the same or different. ]

［式（Ｃ５）及び式（Ｃ６）中、Ｒ^c10、Ｒ^c11、Ｒ^c12、Ｒ^c13及びＲ^c16は、それぞれ独立に、Ｒ^c1と同じ意味を表す。
Ｒ^c14、Ｒ^c15及びＲ^c17は、それぞれ独立に、Ｒ^c4と同じ意味を表す。
ｏ３及びｐ３は、それぞれ独立に、０〜３の整数を表し、ｏ３が２以上のとき、複数のＲ^c1４は同一又は相異なり、ｐ３が２以上のとき、複数のＲ^c15は同一又は相異なる。
Ｌ^c1は、炭素数１〜６のアルカンジイル基、−ＣＯ−、−Ｃ（＝ＮＨ）−、−Ｓ−又はこれらを組合せた２価の基を表す。］

[In Formula (C5) and Formula (C6), R ^c10 , R ^c11 , R ^c12 , R ^c13 and R ^c16 each independently represent the same meaning as R ^c1 .
R ^c14 , R ^c15 and R ^c17 each independently represent the same meaning as R ^c4 .
o3 and p3 each independently represent an integer of 0 to 3, when o3 is 2 or more, the plurality of R ^c14 are the same or different, and when p3 is 2 or more, the plurality of R ^c15 are the same or different. .
L ^c1 represents an alkanediyl group having 1 to 6 carbon atoms, —CO—, —C (═NH) —, —S—, or a divalent group obtained by combining these. ]

［式（Ｃ７）及び式（Ｃ８）中、Ｒ^c18、Ｒ^c19及びＲ^c20は、それぞれ独立に、Ｒ^c4と同じ意味を表す。
ｑ３、ｒ３及びｓ３は、それぞれ独立に０〜３の整数を表し、ｑ３が２以上のとき、複数のＲ^c18は同一又は相異なり、ｒ３が２以上のとき、複数のＲ^c1９は同一又は相異なり、ｓ３が２以上のとき、複数のＲ^c20は同一又は相異なる。
Ｌ^c2は、単結合又は炭素数１〜６のアルカンジイル基、−ＣＯ−、−Ｃ（＝ＮＨ）−、−Ｓ−又はこれらを組合せた２価の基を表す。］

Wherein (C7) and formula ^{(C8), R c18, R} c19 and R ^c20 in each occurrence independently represent the same meaning as R ^c4.
q3, r3 and s3 each independently represents an integer of 0 to 3, and when q3 is 2 or more, a plurality of R ^c18 are the same or different, and when r3 is 2 or more, a plurality of R ^c19 are the same or different. In contrast, when s3 is 2 or more, the plurality of R ^c20 are the same or different.
L ^c2 represents a single bond or an alkanediyl group having 1 to 6 carbon atoms, —CO—, —C (═NH) —, —S—, or a divalent group obtained by combining these. ]

In formula (C1) to formula (C8) and formula (C1-1), the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, alkoxy group, alkanediyl group are the same as those described above. Is mentioned.
Examples of the acyl group include acetyl group, 2-methylacetyl group, 2,2-dimethylacetyl group, propionyl group, butyryl group, isobutyryl group, pentanoyl group, and 2,2-dimethylpropionyl group.

  Examples of the compound represented by the formula (C1) include 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, tri Pentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyl Hexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonyl Amine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diamino-1,2- Examples include diphenylethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane, and preferably diisopropyl. Piruanirin. Particularly preferred include 2,6-diisopropylaniline.

Examples of the compound represented by the formula (C2) include piperazine.
Examples of the compound represented by the formula (C3) include morpholine.
Examples of the compound represented by the formula (C4) include piperidine and hindered amine compounds having a piperidine skeleton described in JP-A No. 11-52575.
Examples of the compound represented by the formula (C5) include 2,2′-methylenebisaniline.
Examples of the compound represented by the formula (C6) include imidazole and 4-methylimidazole.
Examples of the compound represented by the formula (C7) include pyridine and 4-methylpyridine.
Examples of the compound represented by the formula (C8) include 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′-dipiconylamine, bipyridine and the like.

  As ammonium salts, tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3- (trifluoromethyl) phenyltrimethyl Examples include ammonium hydroxide and choline.

  The content of the basic compound (C) in the solid content of the resist composition is preferably about 0.01 to 5% by mass, more preferably about 0.01 to 3% by mass, and particularly preferably 0.8. It is about 01 to 1% by mass.

<Other ingredients>
The resist composition of the present invention may contain other components (hereinafter sometimes referred to as “other components (F)”) other than the above-described components, if 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>
Resist composition includes resin (A), onium carboxylate and acid generator (II), and solvent (E), acid generator (B), basic compound (C) and others used as necessary It can prepare by mixing the component (F). The mixing order is arbitrary and is not particularly limited. The temperature at the time of mixing can select the suitable temperature range from the range of 10-40 degreeC according to the solubility with respect to the solvent (E), such as a kind, etc. of 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 method for producing a resist pattern of the present invention comprises:
(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) The process of heating the composition layer after exposure, (5) The process of developing the composition layer after a heating is included.

Application of the resist composition onto the substrate can be performed by a commonly used apparatus such as a spin coater. By adjusting the conditions of the coating apparatus, the film thickness of the composition after coating can be adjusted. Examples of the substrate include a silicon wafer. On this substrate, and a protective film of SiO ₂ or the like, may be formed antireflection film using a commercially available organic anti-reflective coating composition. Further, this substrate may be washed before applying the resist composition.

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 may be 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 types of laser light, such as those that convert the wavelength of the laser light from the laser to emit harmonic laser light in the far ultraviolet region or vacuum ultraviolet region, those that irradiate an electron beam or extreme ultraviolet light (EUV), etc. it can. In this specification, irradiating these radiations may be collectively referred to as “exposure”. The exposure is usually performed through a mask corresponding to a desired resist pattern. When the exposure light source is an electron beam, a desired pattern may be directly drawn without using a photomask.

  The composition layer after exposure is subjected to heat treatment (so-called post-exposure baking) in order to promote the deprotection group reaction of the resin (A). As heating temperature, it is about 50-200 degreeC normally, Preferably it is about 70-150 degreeC.

  The heated composition layer is usually developed using 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.

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 called 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 is a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, particularly a liquid. It is suitable as a resist composition for immersion exposure and 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 structure of the compound was confirmed by MASS (LC: Agilent 1100 type, MASS: Agilent LC / MSD type or LC / MSD TOF type).
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 HXL-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)

式（ＩＩ−１−ａ）で表される化合物５０部、式（ＩＩ−１−ｂ）で表される化合物１０．３３部及びクロロホルム３５０部を仕込み、２３℃で３０分間攪拌した後、酢酸銅（ＩＩ）０．２０部を仕込み、８０℃で２時間還流した後、濃縮した。回収された濃縮物に、ｔｅｒｔ−ブチルメチルエーテル４４０部を加えて攪拌した後、ろ過することにより、式（ＩＩ−１−ｃ）で表される塩３２．９６部を得た。 Example 1: [Synthesis of a salt represented by the formula (II-1)]

After charging 50 parts of the compound represented by the formula (II-1-a), 10.33 parts of the compound represented by the formula (II-1-b) and 350 parts of chloroform, and stirring at 23 ° C. for 30 minutes, acetic acid was added. 0.20 part of copper (II) was charged, refluxed at 80 ° C. for 2 hours, and concentrated. To the collected concentrate, 440 parts of tert-butyl methyl ether was added and stirred, followed by filtration to obtain 32.96 parts of the salt represented by the formula (II-1-c).

式（ＩＩ−１−ｃ）で表される塩６．００部、式（ＩＩ−１−ｄ）で表される化合物７．８１部、クロロホルム９０部及びイオン交換水２０部を仕込んだ後、２３℃で５時間攪拌した。得られた反応液を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２０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３回繰り返した。得られた残渣を濃縮した後、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル４０部を加えて攪拌した後、ろ過することにより、式（ＩＩ−１）で表される塩９．２９部を得た。

After charging 6.00 parts of the salt represented by the formula (II-1-c), 7.81 parts of the compound represented by the formula (II-1-d), 90 parts of chloroform and 20 parts of ion-exchanged water, Stir at 23 ° C. for 5 hours. The obtained reaction solution was separated and the organic layer was taken out. 20 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 three times. After the obtained residue was concentrated, 40 parts of tert-butyl methyl ether was added to the obtained residue and stirred, followed by filtration to obtain 9.29 parts of the salt represented by the formula (II-1). Obtained.

MASS (ESI (+) Spectrum): M ⁺ 237.1
MASS (ESI (−) Spectrum): M ^- 373.1

式（ＩＩ−１３−ａ）で表される塩２９５部、式（ＩＩ−１３−ｂ）で表される化合物８８．２５部及びクロロホルム７５０部を仕込み、２３℃で１時間攪拌した。得られた反応液を濃縮した後、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル１０００部を加えて攪拌した後、ろ過することにより、式（ＩＩ−１３−ｃ）で表される塩３２８部を得た。 Example 2: Synthesis of salt represented by formula (II-13)

295 parts of a salt represented by the formula (II-13-a), 88.25 parts of a compound represented by the formula (II-13-b) and 750 parts of chloroform were charged and stirred at 23 ° C. for 1 hour. After concentrating the obtained reaction liquid, 1000 parts of tert-butyl methyl ether was added to the obtained residue, and the mixture was stirred and then filtered to obtain 328 parts of the salt represented by the formula (II-13-c). Got.

式（ＩＩ−１３−ｃ）で表される化合物４５部、式（ＩＩ−１３−ｄ）で表される化合物１０．３３部及びクロロホルム３５０部を仕込み、２３℃で３０分間攪拌した後、酢酸銅（ＩＩ）０．２０部を仕込み、８０℃で２時間還流した後、濃縮した。回収された濃縮物に、ｔｅｒｔ−ブチルメチルエーテル４００部を加えて攪拌した後、ろ過することにより、式（ＩＩ−１３−ｅ）で表される塩２９．９８部を得た。

After charging 45 parts of the compound represented by the formula (II-13-c), 10.33 parts of the compound represented by the formula (II-13-d) and 350 parts of chloroform, and stirring at 23 ° C. for 30 minutes, acetic acid was added. 0.20 part of copper (II) was charged, refluxed at 80 ° C. for 2 hours, and concentrated. To the collected concentrate, 400 parts of tert-butyl methyl ether was added and stirred, followed by filtration to obtain 29.98 parts of the salt represented by the formula (II-13-e).

式（ＩＩ−１３−ｅ）で表される塩５．５５部、式（ＩＩ−１３−ｆ）で表される化合物７．８１部、クロロホルム９０部及びイオン交換水２０部を仕込んだ後、２３℃で５時間攪拌した。得られた反応液を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２０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３回繰り返した。得られた残渣を濃縮した後、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル４０部を加えて攪拌した後、ろ過することにより、式（ＩＩ−１３）で表される塩８．９２部を得た。

After charging 5.55 parts of the salt represented by the formula (II-13-e), 7.81 parts of the compound represented by the formula (II-13-f), 90 parts of chloroform and 20 parts of ion-exchanged water, Stir at 23 ° C. for 5 hours. The obtained reaction solution was separated and the organic layer was taken out. 20 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 three times. After the obtained residue was concentrated, 40 parts of tert-butyl methyl ether was added to the obtained residue and stirred, followed by filtration to obtain 8.92 parts of the salt represented by the formula (II-13). Obtained.

MASS (ESI (+) Spectrum): M ⁺ 211.1
MASS (ESI (−) Spectrum): M ^- 373.1

式（ＩＩ−１４−ａ）で表される塩３１５部、式（ＩＩ−１４−ｂ）で表される化合物８８．２５部及びクロロホルム７５０部を仕込み、２３℃で１時間攪拌した。得られた反応液を濃縮した後、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル１０００部を加えて攪拌した後、ろ過することにより、式（ＩＩ−１４−ｃ）で表される塩３３８部を得た。 Example 3: Synthesis of a salt represented by the formula (II-14)

315 parts of a salt represented by the formula (II-14-a), 88.25 parts of a compound represented by the formula (II-14-b) and 750 parts of chloroform were charged and stirred at 23 ° C. for 1 hour. After concentrating the obtained reaction liquid, 1000 parts of tert-butyl methyl ether was added to the obtained residue, stirred, and then filtered to obtain 338 parts of the salt represented by the formula (II-14-c). Got.

式（ＩＩ−１４−ｃ）で表される化合物４８部、式（ＩＩ−１４−ｄ）で表される化合物１０．３３部及びクロロホルム３５０部を仕込み、２３℃で３０分間攪拌した後、酢酸銅（ＩＩ）０．２０部を仕込み、８０℃で２時間還流した後、濃縮した。回収された濃縮物に、ｔｅｒｔ−ブチルメチルエーテル４００部を加えて攪拌した後、ろ過することにより、式（ＩＩ−１４−ｅ）で表される塩３１．１２部を得た。

48 parts of the compound represented by the formula (II-14-c), 10.33 parts of the compound represented by the formula (II-14-d) and 350 parts of chloroform were charged, stirred at 23 ° C. for 30 minutes, and then acetic acid. 0.20 part of copper (II) was charged, refluxed at 80 ° C. for 2 hours, and concentrated. To the collected concentrate, 400 parts of tert-butyl methyl ether was added and stirred, followed by filtration to obtain 31.12 parts of the salt represented by the formula (II-14-e).

式（ＩＩ−１４−ｅ）で表される塩５．７９部、式（ＩＩ−１４−ｆ）で表される化合物７．８１部、クロロホルム９０部及びイオン交換水２０部を仕込んだ後、２３℃で５時間攪拌した。得られた反応液を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２０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３回繰り返した。得られた残渣を濃縮した後、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル４０部を加えて攪拌した後、ろ過することにより、式（ＩＩ−１４）で表される塩８．９７部を得た。

After charging 5.79 parts of a salt represented by the formula (II-14-e), 7.81 parts of a compound represented by the formula (II-14-f), 90 parts of chloroform and 20 parts of ion-exchanged water, Stir at 23 ° C. for 5 hours. The obtained reaction solution was separated and the organic layer was taken out. 20 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 three times. After the obtained residue was concentrated, 40 parts of tert-butyl methyl ether was added to the obtained residue and stirred, followed by filtration to obtain 8.97 parts of the salt represented by the formula (II-14). Obtained.

MASS (ESI (+) Spectrum): M ⁺ 225.1
MASS (ESI (−) Spectrum): M ^- 373.1

式（ＩＩ−８−ｃ）で表される塩７．００部、式（ＩＩ−１−ｄ）で表される化合物７．６２部、クロロホルム８４部及びイオン交換水３０部を仕込んだ後、２３℃で５時間攪拌した。得られた反応液を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３０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３回繰り返した。得られた残渣を濃縮した後、得られた残渣に、アセトニトリル４０部を加えて攪拌した後、濃縮することにより、式（ＩＩ−８）で表される塩１０．２７部を得た。 Synthesis Example 1: [Synthesis of salt represented by formula (II-8)]

After charging 7.00 parts of the salt represented by the formula (II-8-c), 7.62 parts of the compound represented by the formula (II-1-d), 84 parts of chloroform and 30 parts of ion-exchanged water, Stir at 23 ° C. for 5 hours. The obtained reaction solution was separated and the organic layer was taken out. 30 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 three times. After the obtained residue was concentrated, 40 parts of acetonitrile was added to the obtained residue, stirred, and then concentrated to obtain 10.27 parts of the salt represented by the formula (II-8).

MASS (ESI (+) Spectrum): M ⁺ 305.1
MASS (ESI (−) Spectrum): M ^- 373.1

式（Ｂ１−５−ａ）で表される塩５０．４９部及びクロロホルム２５２．４４部を反応器に仕込み、２３℃で３０分間攪拌した後、式（Ｂ１−５−ｂ）で表される化合物１６．２７部を滴下し、２３℃で１時間攪拌することにより、式（Ｂ１−５−ｃ）で表される塩を含む溶液を得た。得られた式（Ｂ１−５−ｃ）で表される塩を含む溶液に、式（Ｂ１−５−ｄ）で表される塩４８．８０部及びイオン交換水８４．１５部を添加し、２３℃で１２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８４．１５部を添加し、水洗した。この操作を５回繰り返した。得られたクロロホルム層に、活性炭３．８８部を添加攪拌し、ろ過した。回収されたろ液を濃縮し、得られた残渣に、アセトニトリル１２５．８７部を添加攪拌し、濃縮した。得られた残渣に、アセトニトリル２０．６２部及びｔｅｒｔ−ブチルメチルエーテル３０９．３０部を加えて２３℃で３０分間攪拌し、上澄み液を除去し、濃縮した。得られた残渣に、ｎ−ヘプタン２００部を添加、２３℃で３０分間攪拌し、ろ過することにより、式（Ｂ１−５）で表される塩６１．５４部を得た。
ＭＡＳＳ（ＥＳＩ（＋）Ｓｐｅｃｔｒｕｍ）：Ｍ^＋ ３７５．２
ＭＡＳＳ（ＥＳＩ（−）Ｓｐｅｃｔｒｕｍ）：Ｍ⁻ ３３９．１ Synthesis Example 2: Synthesis of salt represented by formula (B1-5)

50.49 parts of the salt represented by the formula (B1-5-a) and 252.44 parts of chloroform are charged into a reactor, stirred at 23 ° C. for 30 minutes, and then represented by the formula (B1-5-b). 16.27 parts of the compound was added dropwise and stirred at 23 ° C. for 1 hour to obtain a solution containing a salt represented by the formula (B1-5-c). To the obtained solution containing the salt represented by the formula (B1-5-c), 48.80 parts of the salt represented by the formula (B1-5-d) and 84.15 parts of ion-exchanged water are added, The mixture was stirred at 23 ° C. for 12 hours. Since the resulting reaction solution was separated into two layers, the chloroform layer was separated and removed, and 84.15 parts of ion-exchanged water was further added to the chloroform layer and washed with water. This operation was repeated 5 times. To the obtained chloroform layer, 3.88 parts of activated carbon was added and stirred, followed by filtration. The collected filtrate was concentrated, and 125.87 parts of acetonitrile was added to the resulting residue, and the mixture was stirred and concentrated. To the obtained residue, 20.62 parts of acetonitrile and 309.30 parts of tert-butyl methyl ether were added and stirred at 23 ° C. for 30 minutes, and the supernatant was removed and concentrated. To the obtained residue, 200 parts of n-heptane was added, stirred at 23 ° C. for 30 minutes, and filtered to obtain 61.54 parts of the salt represented by the formula (B1-5).
MASS (ESI (+) Spectrum): M ⁺ 375.2
MASS (ESI (−) Spectrum): M ^- 339.1

Synthesis Example 3 [Synthesis of Salt 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）で表される塩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 the salt represented by the 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 4 [Synthesis of salt 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）で表される塩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 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 6.84 parts of the salt represented by the formula (B1-22). Got.

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

Synthesis of Resin (A) Compounds (monomers) used in the synthesis of resin (A) are shown below. Hereinafter, these monomers are referred to as “monomer (a1-1-2)” or the like according to the formula number.

Synthesis Example 5 [Synthesis of Resin A1]
As the monomer, using monomer (a1-1-3), monomer (a1-2-9), monomer (a2-1-1), monomer (a3-2-3) and monomer (a3-1-1), The molar ratio [monomer (a1-1-3): monomer (a1-2-9): monomer (a2-1-1): monomer (a3-2-3): monomer (a3-1-1)] 21.6: 14.2: 6.6: 23.1: 34.5 The mixture was mixed so that 1.5 mass times propylene glycol monomethyl ether acetate of the total monomer amount was added to obtain a solution. To this solution, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 0.95 mol% and 2.85 mol%, respectively, based on the total monomer amount, and these were added at 73 ° C. Heated for about 5 hours. The obtained reaction mixture was poured into a large amount of methanol / ion-exchanged water = 4/1 mixing solution to precipitate the resin, and the resin was filtered to obtain a resin A1 having a weight average molecular weight of 1.0 × 10 ⁴ (co-polymer). Polymer) with a yield of 70%. This resin A1 has the following structural units and was soluble in butyl acetate.

Synthesis Example 6 [Synthesis of Resin A2]
As the monomer, monomer (a1-1-2), monomer (a1-2-3), monomer (a3-2-3), and monomer (a3-1-1) were used, and the molar ratio [monomer (a1-1 -2): monomer (a1-2-3): monomer (a2-1-3): monomer (a3-2-3): monomer (a3-1-1)] becomes 27: 14: 15: 44 Then, propylene glycol monomethyl ether acetate of 1.5 mass times the total monomer amount was added to make a solution. To this solution, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 0.8 mol% and 2.4 mol%, respectively, with respect to the total monomer amount, and these were added at 73 ° C. Heated for about 5 hours. The obtained reaction mixture was poured into a large amount of methanol / ion-exchanged water = 4/1 mixing solution to precipitate the resin, and the resin was filtered to obtain a resin A2 having a weight average molecular weight of 1.3 × 10 ⁴ (co-polymer). Polymer) with a yield of 84%. This resin A2 had the following structural units and was soluble in butyl acetate.

Synthesis Example 7 [Synthesis of Resin A3]
The monomer (a1-1-2), monomer (a2-1-1) and monomer (a3-1-1) are mixed in a molar ratio [monomer (a1-1-2): monomer (2-1-1): Monomer (a3-1-1)] was mixed so as to be 50:25:25, and 1.5 mass times dioxane was further mixed with respect to the total mass of all monomers. To the obtained mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added as initiators in proportions of 1 mol% and 3 mol%, respectively, with respect to the total number of moles of all monomers. did. This was polymerized by heating at 80 ° C. for about 8 hours. Thereafter, the polymerization reaction solution was poured into a large amount of a mixed solvent of methanol and water (mass ratio methanol: water = 4: 1) to precipitate the resin. This resin was filtered and collected. Again, the resin is dissolved in dioxane, poured into a mixed solvent of a large amount of methanol and water, the resin is precipitated, and the precipitated resin is filtered and recovered three times for reprecipitation purification, and the weight average Resin A3 (copolymer) having a molecular weight of about 9.2 × 10 ³ was obtained in a yield of 60%. This resin A3 had the following structural units and was soluble in butyl acetate.

Synthesis Example 8 [Synthesis of Resin A4]
As the monomer, monomer (a1-1-3), monomer (a1-2-9), monomer (a2-1-3) and monomer (a3-4-2) were used, and the molar ratio [monomer (a1-1 -3): Monomer (a1-2-9): Monomer (a2-1-3): Monomer (a3-4-2)] are mixed at 45: 14: 2.5: 38.5, A solution was prepared by adding propylene glycol monomethyl ether acetate of 1.5 mass times the total monomer amount. 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 A4 (copolymer) having a molecular weight of 7.6 × 10 ³ was obtained in a yield of 68%. This resin A4 has the following structural units.

Synthesis Example 9 [Synthesis of Resin X1]
Monomer (a4-1-7) was used as a monomer, and 1.5 mass times dioxane of the total monomer amount was added to prepare a solution. To this solution, 0.7 mol% and 2.1 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile), respectively, as initiators were added 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 obtained resin was again dissolved in dioxane, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by two reprecipitation operations of filtering the resin, and a weight average molecular weight of 1.8. A × 10 ⁴ polymer was obtained with a yield of 77%. This polymer has the following structural units, and this is designated as resin X1.

Examples 4-16, Comparative Examples 1 and 2
<Preparation of resist composition>
Each of the components shown below was dissolved in a solvent in parts by mass shown in Table 1, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

ＩＩ−８：式（ＩＩ−８）で表される塩
ＩＩ−１３：式（ＩＩ−１３）で表される塩
ＩＩ−１４：式（ＩＩ−１４）で表される塩
Ｂ１−３：特開２００６−２５７０７８号（住友化学）の実施例に従って合成

Ｂ１−５：式（Ｂ１−５）で表される塩
Ｂ１−２１：式（Ｂ１−２１）で表される塩
Ｂ１−２２：式（Ｂ１−２２）で表される塩
＜塩基性化合物：クエンチャー＞
Ｃ１：２，６−ジイソプロピルアニリン（東京化成工業（株）製）
＜式（Ｉ）で表される化合物＞
Ｄ１：（東京化成工業（株）製）

＜溶剤＞
プロピレングリコールモノメチルエーテルアセテート ２６５部
プロピレングリコールモノメチルエーテル ２０部
２−ヘプタノン ２０部
γ−ブチロラクトン ３．５部 <Resin>
Resins A1 to A4 and Resin X1 synthesized in the synthesis example described above
<Acid generator>
II-1: salt represented by formula (II-1) II-7: salt represented by formula (II-7) (obtained from BASF Japan Ltd.)

II-8: salt represented by formula (II-8) II-13: salt represented by formula (II-13) II-14: salt represented by formula (II-14) B1-3: special Synthesis according to examples of Kai 2006-257078 (Sumitomo Chemical)

B1-5: salt represented by formula (B1-5) B1-21: salt represented by formula (B1-21) B1-22: salt represented by formula (B1-22) <basic compound: Quencher>
C1: 2,6-diisopropylaniline (manufactured by Tokyo Chemical Industry Co., Ltd.)
<Compound represented by formula (I)>
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

<Manufacture of resist pattern>
An organic antireflective coating composition (ARC-29; manufactured by Nissan Chemical Co., Ltd.) is applied to a silicon wafer and baked at 205 ° C. for 60 seconds to form an organic antireflective coating having a thickness of 78 nm. Formed. Next, each of the resist compositions in Table 1 was spin-coated on the organic antireflection film so that the film thickness after drying was 85 nm. The silicon wafer coated with the resist composition was pre-baked on a direct hot plate at a temperature described in the “PB” column of Table 1 for 60 seconds to form a composition layer. An ArF excimer laser stepper for immersion exposure (XT: 1900 Gi; manufactured by ASML, NA = 1.35, 3/4 Annular XY polarized light) is used as a contact hole pattern (hole) on the composition layer formed on the silicon wafer. Using a mask for forming a pitch of 100 nm / hole diameter of 70 nm, exposure was performed while changing the exposure amount stepwise. Note that ultrapure water was used as the immersion medium.
After the exposure, the silicon wafer was post-exposure baked on a hot plate at a temperature described in the “PEB” column of Table 1 for 60 seconds. Next, this silicon wafer was subjected to paddle development for 60 seconds with a 2.38% tetramethylammonium hydroxide aqueous solution to obtain a resist pattern.

  In each resist pattern, an exposure amount at which the hole diameter becomes 55 nm was defined as effective sensitivity.

<Evaluation of CD uniformity (CDU)>
In terms of effective sensitivity, the hole diameter of the resist pattern was measured 24 times per hole, and the average value was taken as the average hole diameter of one hole. The average hole diameter was measured for 400 holes formed on the same wafer, and the standard deviation was determined using these as the population.
When the standard deviation is less than 1.55 nm,
When the standard deviation is 1.55 nm or more and less than 2.00 nm, “○”,
“X” when the standard deviation is 2.00 nm or more,
Judged as each. The results are shown in Table 2. In Table 2, the numbers in parentheses indicate standard deviation values (nm).

  From the above results, it can be seen that according to the resist composition of the present invention, a resist pattern having excellent CD uniformity (CDU) can be produced.

  According to the resist composition of the present invention, a resist pattern having excellent CD uniformity (CDU) can be produced.

Claims (7)

A resist composition comprising a resin containing a structural unit having an acid labile group, a carboxylic acid onium salt, and an acid generator represented by formula (II).

[In the formula (II),
R ³ represents a hydrocarbon group having 1 to 24 carbon atoms, and —CH ₂ — contained in the hydrocarbon group may be replaced by —O— or —CO—.
Z ⁺ represents an organic cation. ] The resist composition according to claim 1, wherein the onium carboxylate is a salt represented by the formula (IB).

[In the formula (IB),
R ¹ and R ² are each independently a 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, an acyloxy group having 2 to 7 carbon atoms, or a carbon number. Represents 2 to 7 alkoxycarbonyl groups, nitro groups or halogen atoms.
m and n each independently represents an integer of 0 to 4, and when m is 2 or more, the plurality of R ¹ are the same or different, and when n is 2 or more, the plurality of R ² are the same or different. . ] The resist composition according to claim 1 or 2, wherein Z ⁺ in formula (II) is a cation represented by formula (b2-5).

[In Formula (b2-5), R ⁵ represents an alkyl group having 1 to 12 carbon atoms, and —CH ₂ — contained in the alkyl group may be replaced by —O— or —CO—. b represents an integer of 0 to 3. When b is 2 or more, the plurality of R ⁵ are the same or different. ] The resist composition according to claim 3, wherein R ⁵ is an alkyl group having 1 to 6 carbon atoms. (1) The process of apply | coating the resist composition as described in any one of Claims 1-4 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,
A method for producing a resist pattern including: An acid generator represented by the formula (IIAa).

[In Formula (IIAa), R ⁴ represents an alkyl group having 1 to 4 carbon atoms. a represents an integer of 0 to 3. R ⁵ represents an alkyl group having 1 to 12 carbon atoms, and —CH ₂ — contained in the alkyl group may be replaced by —O— or —CO—. b represents an integer of 0 to 3. When b is 2 or more, the plurality of R ⁵ are the same or different. ] The acid generator according to claim 6, wherein R ⁵ is an alkyl group having 1 to 6 carbon atoms.