JP2011201867A - Compound, resin and resist composition - Google Patents

Abstract

［式中、Ｗは飽和炭化水素環を表し、該環に含まれる−ＣＨ_２−は、−Ｏ−、−ＳＯ_２−又は−ＣＯ−で置き換わっていてもよい；Ａ^１は、単結合又は２価の飽和炭化水素基を表し、前記基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい；Ｒ^１は、水素原子、ハロゲン原子又はハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。］
【選択図】なしAn object of the present invention is to provide a resist composition capable of forming a pattern having excellent resolution and line edge roughness (LER).
A compound represented by formula (I).

[Wherein, W represents a saturated hydrocarbon ring, and —CH ₂ — contained in the ring may be replaced by —O—, —SO ₂ — or —CO—; A ¹ is a single bond or Represents a divalent saturated hydrocarbon group, and —CH ₂ — contained in the group may be replaced by —O— or —CO—; R ¹ has a hydrogen atom, a halogen atom or a halogen atom; An alkyl group having 1 to 6 carbon atoms may be represented. ]
[Selection figure] None

Description

  The present invention relates to a compound, a resin, and a resist composition, and more particularly to a resin used for microfabrication of a semiconductor and a resist composition containing the same.

A resist composition used for microfabrication of a semiconductor using a lithography technique contains a resin.
For example, in Patent Document 1, 2-ethyl-2-adamantyl methacrylate, 3-hydroxy-1-adamantyl methacrylate and α-methacryloyloxy-γ-butyrolactone are used as the resin in a molar ratio of 50:25:25. A resist composition comprising a polymer obtained by charging and polymerizing, an acid generator, a basic compound, and a solvent is described.

JP 2006-257078 A

  However, with conventional compounds, the resolution and line edge roughness (LER) of the pattern formed using a resist composition containing a resin obtained by polymerizing the compound may not always be satisfactory.

［式（Ｉ）中、
Ｗは、炭素数３〜３６の飽和炭化水素環を表し、該飽和炭化水素環に含まれる−ＣＨ_２−は、−Ｏ−、−ＳＯ_２−又は−ＣＯ−で置き換わっていてもよい。
Ａ^１は、単結合又は２価の炭素数１〜１７の飽和炭化水素基を表し、前記２価の飽和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。
Ｒ^１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。］ The present invention includes the following inventions.
[1] A compound represented by the formula (I).

[In the formula (I),
W represents a saturated hydrocarbon ring having 3 to 36 carbon atoms, and —CH ₂ — contained in the saturated hydrocarbon ring may be replaced by —O—, —SO ₂ — or —CO—.
A ¹ represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and —CH ₂ — contained in the divalent saturated hydrocarbon group is replaced by —O— or —CO—. May be.
R ¹ represents a C 1-6 alkyl group, a hydrogen atom or a halogen atom which may have a halogen atom. ]

［式（ＩＩ）中、Ｗ、Ａ^１及びＲ^１は、上記と同じ意味を表す。］
〔３〕Ａ^１が、単結合又は＊−ＣＨ_２−ＣＯ−Ｏ−（＊は−Ｏ−との結合手を表す。）で表される〔１〕又は〔２〕記載の化合物。 [2] The compound according to [1] represented by formula (II).

[In Formula (II), W, A ¹ and R ¹ represent the same meaning as described above. ]
[3] The compound according to [1] or [2], in which A ¹ is represented by a single bond or * —CH ₂ —CO—O— (* represents a bond to —O—).

[4] A resin having a structural unit derived from the compound according to any one of [1] to [3].
[5] The resin according to [4], which has an acid labile group, is insoluble or hardly soluble in an aqueous alkali solution, and can be dissolved in an aqueous alkali solution by the action of an acid.

[6] A resist composition comprising the resin according to the above [4] or [5] and an acid generator.
[7] The resist composition according to [6], which contains a basic compound.

[8] (1) A step of applying the resist composition according to [6] or [7] 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 using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) A method for producing a resist pattern, comprising a step of developing the heated composition layer using a developing device.

  According to the compound of the present invention, a pattern having excellent resolution and line edge roughness (LER) can be formed using a resist composition containing a resin obtained by polymerizing the compound.

  The compound of the present invention is a compound represented by the formula (I).

ここで、芳香族炭化水素としては、ベンゼン、ナフタレン、アントラセン、ｐ−トルエン、ｐ−ｔｅｒｔ−ブチルベンゼン、ｐ−アダマンチルベンゼン、１，２−ジメチルベンゼン、１，３−ジメチルベンゼン、１，４−ジメチルベンゼン、（１−メチルエチル）ベンゼン、１，３，５−トリメチルベンゼン、ジフェニル、フェナントレン、２，６−ジエチルベンゼン、２−メチル−６−エチルベンゼン等が挙げられる。 In the formula (I), the saturated hydrocarbon ring may be monocyclic or polycyclic. For example, a monocyclic saturated hydrocarbon ring such as cycloalkane (for example, cycloalkane such as cyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, cycloheptane, and cyclooctane) can be used. Examples thereof include polycyclic saturated hydrocarbon rings such as a ring obtained by hydrogenating a condensed aromatic hydrocarbon (for example, hydronaphthalene) and a bridged cyclic hydrocarbon (for example, adamantane, norbornane, methylnorbornane). Further, a ring in which a bridged ring (for example, norbornane) and a single ring (for example, cycloheptane, cyclohexane) or a polycycle (for example, decahydronaphthalene) are condensed or a ring in which the bridged rings are condensed; Combined rings (methylcyclohexane, dimethylcyclohexane, methylnorbornane) and the like can be mentioned.

Here, examples of the aromatic hydrocarbon include benzene, naphthalene, anthracene, p-toluene, p-tert-butylbenzene, p-adamantylbenzene, 1,2-dimethylbenzene, 1,3-dimethylbenzene, 1,4- Examples thereof include dimethylbenzene, (1-methylethyl) benzene, 1,3,5-trimethylbenzene, diphenyl, phenanthrene, 2,6-diethylbenzene, 2-methyl-6-ethylbenzene and the like.

Examples of the group in which —CH ₂ — contained in the saturated hydrocarbon ring is replaced by —O—, —SO ₂ — or —CO— include the following groups.

The saturated hydrocarbon ring may have a substituent. Examples of the substituent include a hydroxyl group, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and an aromatic hydrocarbon group having 6 to 10 carbon atoms.
Examples of the alicyclic hydrocarbon group having 3 to 12 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, an adamantyl group, and a norbornyl group.
Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentoxy group, an n-hexoxy group, and an octyloxy group. , 2-ethylhexyloxy group and the like.
Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include a phenyl group, a naphthyl group, and an anthryl group.

Examples of the divalent saturated hydrocarbon group include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic saturated hydrocarbon group, and two or more of these groups are combined. It may be a thing.
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, methylidene group, ethylidene group, propylidene group, 2-propylidene group;
An alkyl group (particularly an alkyl group having 1 to 4 carbon atoms, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, etc.) is added to the linear alkanediyl. Those having a side chain, for example, 1-methyl-1,3-propylene group, 2-methyl-1,3-propylene group, 2-methyl-1,2-propylene group, 1-methyl-1,4-propylene group Branched alkanediyl groups such as butylene and 2-methyl-1,4-butylene;
A monocyclic saturated hydrocarbon group which is a cycloalkylene group such as a 1,3-cyclobutylene group, a 1,3-cyclopentylene group, a 1,4-cyclohexylene group, a 1,5-cyclooctylene group;
Examples thereof include polycyclic saturated hydrocarbon groups such as 1,4-norbornylene group, 2,5-norbornylene group, 1,5-adamantylene group and 2,6-adamantylene group.

［式（Ｘ^x−Ａ）〜式（Ｘ^ｘ−Ｃ）中、
Ｘ^Ｘ１及びＸ^Ｘ２は、それぞれ独立に、単結合また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を表す。ただし、式（Ｘ^ｘ−Ａ）〜式（Ｘ^ｘ−Ｃ）で表される基の炭素数は１〜１７である。］
飽和炭化水素基に含まれる−ＣＨ_２−が−Ｏ−又は−ＣＯ−で置き換わっていてもよい基としては、例えば、以下の基が挙げられる。＊は、−ＣＯ−Ｏ−との結合手を表す。 In particular, examples of the group containing cycloalkylene include groups represented by the formula (X ^x -A) to the formula (X ^x -C).

[In the formulas (X ^x -A) to (X ^x -C),
X ^X1 and X ^X2 each independently represent a C 1-6 alkanediyl group which may have a single bond or a substituent. However, the carbon number of the group represented by the formula (X ^x -A) to the formula (X ^x -C) is 1 to 17. ]
Examples of the group in which —CH ₂ — contained in the saturated hydrocarbon group may be replaced by —O— or —CO— include the following groups. * Represents a bond with -CO-O-.

The saturated hydrocarbon group may have a substituent. Examples of the substituent include a halogen atom, a hydroxy group, a carboxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, and an aromatic carbonization having 6 to 20 carbon atoms. Examples thereof include a hydrogen group, an aralkyl group having 7 to 21 carbon atoms, and an acyl group having 2 to 4 carbon atoms.
Examples of the halogen atom include fluorine, chlorine, bromine and iodine atoms.
Examples of the aliphatic hydrocarbon group include methyl group, ethyl group, n-propyl group, 1-methylethyl group (isopropyl group), n-butyl group, 1,1-dimethylethyl group (tert-butyl group), 2, 2-dimethylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1,2-dimethylpropyl group, 2,2-dimethylpropyl group, 1-ethylpropyl group, n-pentyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, n-hexyl group, 1-propylbutyl group, pentyl group, 1-methylpentyl group, 1,4-dimethylhexyl group, heptyl group, 1-methylheptyl group, octyl group, Examples thereof include alkyl groups such as nonyl group, decyl group, undecyl group, and dodecyl group.
Examples of the aralkyl group include benzyl, phenethyl, phenylpropyl, trityl, naphthylmethyl group, naphthylethyl group, and the like.
Examples of the acyl group include acetyl, propionyl, butyryl and the like.

  Examples of the alkyl group which may have a halogen atom include an alkyl group and a halogenated alkyl group. Examples of the halogenated alkyl group include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, and a perfluorobutyl group.

Ａ^１としては、単結合又は＊−ＣＨ_２−ＣＯ−Ｏ−（＊は−Ｏ−との結合手を表す。）であることが好ましい。
Ｒ^１は、水素原子又はメチル基であることが好ましい。 In formula (I), W is preferably a ring represented by formula (a1-1) to formula (a1-3). In addition, the bond to A ¹ and the carbon atom shared with the adjacent ring may be in any position.

A ¹ is preferably a single bond or * —CH ₂ —CO—O— (* represents a bond to —O—).
R ¹ is preferably a hydrogen atom or a methyl group.

また、以下の化合物が好ましい。

式中、Ｒ^１及びＡ^１は、上記と同じ意味を表す。
なかでも、式（ＩＩ）表される化合物が好ましく、式（ＩＩ’）表される化合物がより好ましい。 Examples of the compound (I) include the following compounds.

Moreover, the following compounds are preferable.

In the formula, R ¹ and A ¹ represent the same meaning as described above.
Especially, the compound represented by Formula (II) is preferable and the compound represented by Formula (II ') is more preferable.

More specifically, examples of the compound represented by the formula (I) include compounds represented by the following.

［式（Ｉ’）中、Ａ^１、Ｒ^１及びＷは、上記と同じ意味を表す。］ The compound represented by the formula (I) is produced, for example, by reacting a ketone (C═O) in the compound represented by the formula (I ′) with malonic acid in sulfuric acid in acetic anhydride. be able to.

[In formula (I ′), A ¹ , R ¹ and W represent the same meaning as described above. ]

<Resin (hereinafter sometimes referred to as “resin (A)”)>
The resin of the present invention has a structural unit derived from the compound represented by the formula (I).
The content of the structural unit derived from the compound represented by the formula (I) in the resin (A) is usually 1 to 100 mol%, preferably 3 to 50 mol% in all units of the resin (A). Yes, more preferably 5 to 30 mol%.

In addition to the structural unit derived from the compound represented by formula (I), the resin of the present invention more preferably contains a structural unit derived from a monomer having an acid labile group. That is, any of a polymer / oligomer mixture or a copolymer containing these structural units may be used. Such a resin is a resin that is insoluble or hardly soluble in an alkaline aqueous solution, and becomes a resin that can be dissolved in an alkaline aqueous solution by the action of an acid.
A resin that can be dissolved in an alkaline aqueous solution by the action of an acid can be produced by polymerizing a monomer having an acid labile group (hereinafter sometimes referred to as “monomer having an acid labile group (a1)”). It becomes alkali-soluble by the action of acid. “Can be dissolved in an alkaline aqueous solution by the action of an acid” means “insoluble or hardly soluble in an alkaline aqueous solution before contact with an acid but becomes soluble in an alkaline aqueous solution after contact with an acid”. To do. As the monomer (a1) having an acid labile group, one type may be used alone, or two or more types may be used in combination.

<Monomer (a1) having an acid labile group>
The term “acid-labile group” means a group that cleaves a leaving group upon contact with an acid to form a hydrophilic group (for example, a hydroxy group or a carboxy group). Examples of the acid labile group include an alkoxycarbonyl group represented by the formula (1) in which —O— is bonded to a tertiary carbon atom (excluding a bridgehead carbon atom of a bridged cyclic hydrocarbon group) (ie, An ester bond having a tertiary alcohol residue). Hereinafter, the group represented by the formula (1) may be referred to as “acid-labile group (1)”.

式（１）中、Ｒ^a1〜Ｒ^a3は、それぞれ独立に、脂肪族炭化水素基又は飽和炭化水素基を表すか或いはＲ^a1及びＲ^a2は互いに結合して環を形成していてもよい。＊は結合手を表す（以下同じ）。

In formula (1), R ^{a1 to} R ^a3 each independently represents an aliphatic hydrocarbon group or a saturated hydrocarbon group, or R ^a1 and R ^a2 may be bonded to each other to form a ring. * Represents a bond (same below).

式（１）では、飽和炭化水素基は、好ましくは炭素数３〜２０であり、より好ましくは炭素数３〜１２である。 Examples of the saturated hydrocarbon group include the same groups as described above, and the groups shown below are particularly preferable.

In the formula (1), the saturated hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.

Examples of the ring formed by combining R ^a1 and R ^a2 with each other include a saturated hydrocarbon group and an aromatic hydrocarbon group. Such a ring preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.

Examples of the acid labile group (1) include a 1,1-dialkylalkoxycarbonyl group (in the group (1), R ^{a1 to} R ^a3 are alkyl groups, preferably a tert-butoxycarbonyl group), 2-alkyl-2-adamantyloxycarbonyl group (in the formula (1), R ^a1 , R ^a2 and a carbon atom form an adamantyl group, and R ^a3 is an alkyl group) and 1- (1-adamantyl)- 1-alkylalkoxycarbonyl groups (in the formula (1), R ^a1 and R ^a2 are alkyl groups and R ^a3 is an adamantyl group) and the like.

The monomer (a1) having an acid labile group is preferably a monomer having an acid labile group (1) and a carbon-carbon double bond, more preferably an acid labile group (1). (Meth) acrylic monomer having
Among the (meth) acrylic monomers having the acid-labile group (1), those having a saturated hydrocarbon group having 5 to 20 carbon atoms are preferable. If a resin obtained by polymerizing the monomer (a1) having a bulky structure such as a saturated hydrocarbon group is used, the resolution of the resist can be improved.

  Among (meth) acrylic monomers having an acid labile group (1) and a saturated hydrocarbon group, an acid labile group represented by formula (a1-1) or formula (a1-2) The monomer which has is preferable. These may be used alone or in combination of two or more.

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の整数を表す。但しＬ^a1及びＬ^a2で列挙した−Ｏ−等は、それぞれ、左側で式（ａ１−１）及び式（ａ１−２）の−ＣＯ−と結合し、右側でアダマンチル基又はシクロへキシル基と結合することを意味する。
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の脂肪族炭化水素基又は炭素数３〜１０の飽和炭化水素基を表す。
ｍ１は０〜１４の整数を表す。
ｎ１は０〜１０の整数を表す。
ｎ２は０又は１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—, and k1 represents an integer of 1 to 7. However, —O— and the like enumerated for L ^a1 and L ^a2 are respectively bonded to —CO— of the formula (a1-1) and the formula (a1-2) on the left side, and to an adamantyl group or cyclohexyl group on the right side. Means to join.
R ^a4 and R ^a5 each independently represent a hydrogen atom or a methyl group.
R ^a6 and R ^a7 each independently represent an aliphatic hydrocarbon group having 1 to 8 carbon atoms or a saturated hydrocarbon group having 3 to 10 carbon atoms.
m1 represents the integer of 0-14.
n1 represents an integer of 0 to 10.
n2 represents an integer of 0 or 1.

In the formula (a1-1) and the formula (a1-2), L ^a1 and L ^a2 are preferably, -O- or _{-O- (CH 2) f1 -CO-} O- and is (wherein f1 is 1 to 4), and more preferably -O-.
R ^a4 and R ^a5 are preferably methyl groups.
The aliphatic hydrocarbon group represented by R ^a6 and R ^a7 preferably has 6 or less carbon atoms. The saturated hydrocarbon group preferably has 8 or less carbon atoms, more preferably 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.
k1 is preferably an integer of 1 to 4, more preferably 1.

  As a monomer (a1-1) which has an adamantyl group, the following are mentioned, for example. Among them, 2-methyl-2-adamantyl (meth) acrylate, 2-ethyl-2-adamantyl (meth) acrylate and 2-isopropyl-2-adamantyl (meth) acrylate are preferable, and those in the form of methacrylate are more preferable.

  As a monomer (a1-2) which has a cyclohexyl group, the following are mentioned, for example. Among these, 1-ethyl-1-cyclohexyl (meth) acrylate is preferable, and 1-ethyl-1-cyclohexyl methacrylate is more preferable.

  The content of the structural unit derived from the monomer represented by the formula (a1-1) or the formula (a1-2) in the resin is usually 10 to 95 mol%, preferably 15 to 90, in all units of the resin. It is mol%, More preferably, it is 20-85 mol%.

  Examples of the monomer having an acid labile group (1) and a carbon-carbon double bond include a monomer having a norbornene ring represented by the formula (a1-3). Since the resin having a structural unit derived from the monomer (a1-3) having an acid labile group has a bulky structure, the resolution of the resist can be improved. Furthermore, the monomer (a1-3) having an acid labile group can improve the resistance to dry etching of a resist by introducing a rigid norbornane ring into the main chain of the resin.

式（ａ１−３）中、
Ｒ^a9は、水素原子、置換基（例えば、ヒドロキシ基）を有していてもよい炭素数１〜３の脂肪族炭化水素基、カルボキシ基、シアノ基又は基−ＣＯＯＲ^a13（Ｒ^a13は、炭素数１〜８の脂肪族炭化水素基又は炭素数３〜８の飽和炭化水素基を表し、前記脂肪族炭化水素基及び前記飽和炭化水素基の水素原子はヒドロキシ基で置換されていてもよく、前記脂肪族炭化水素基及び前記飽和炭化水素基の−ＣＨ_２−は−Ｏ−又は−ＣＯ−で置き換わっていてもよい。）を表す。
Ｒ^a10〜Ｒ^a12は、それぞれ独立に、炭素数１〜１２の脂肪族炭化水素基又は炭素数３〜１２の飽和炭化水素基を表すか、或いはＲ^a10及びＲ^a11は互いに結合して環を形成していてもよく、前記脂肪族炭化水素基及び前記飽和炭化水素基の水素原子はヒドロキシ基等で置換されていてもよく、前記脂肪族炭化水素基及び前記飽和炭化水素基の−ＣＨ_２−は−Ｏ−又は−ＣＯ−で置き換わっていてもよい。

In formula (a1-3),
R ^a9 represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 3 carbon atoms which may have a substituent (for example, a hydroxy group), a carboxy group, a cyano group, or a group —COOR ^a13 (R ^a13 represents carbon Represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms or a saturated hydrocarbon group having 3 to 8 carbon atoms, and the hydrogen atom of the aliphatic hydrocarbon group and the saturated hydrocarbon group may be substituted with a hydroxy group, -CH ₂ of the aliphatic hydrocarbon group and the saturated hydrocarbon group - represents a may be replaced by -O- or -CO-)..
R ^{a10 to} R ^a12 each independently represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms or a saturated hydrocarbon group having 3 to 12 carbon atoms, or R ^a10 and R ^a11 are bonded to each other to form a ring. The hydrogen atom of the aliphatic hydrocarbon group and the saturated hydrocarbon group may be substituted with a hydroxy group or the like, and —CH _{2 of the} aliphatic hydrocarbon group and the saturated hydrocarbon group may be formed. -May be replaced by -O- or -CO-.

Examples of the aliphatic hydrocarbon group which may have a substituent for R ^a9 include a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, and a 2-hydroxyethyl group.
^Examples of R ^a13 include a methyl group, an ethyl group, a propyl group, a 2-oxo-oxolan-3-yl group, and a 2-oxo-oxolan-4-yl group.
Examples of R ^{a10 to} R ^a12 include a methyl group, an ethyl group, a cyclohexyl group, a methylcyclohexyl group, a hydroxycyclohexyl group, an oxocyclohexyl group, and an adamantyl group.
Examples of the ring formed by R ^a10 , R ^a11 and the carbon to which they are bonded include saturated hydrocarbon groups. Specific examples include a cyclohexyl group and an adamantyl group.

  Examples of the monomer (a1-3) having a norbornene ring include, for example, 5-norbornene-2-carboxylic acid-tert-butyl, 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, 5-norbornene-2 -1-methylcyclohexyl carboxylate, 2-methyl-2-adamantyl 5-norbornene-2-carboxylate, 2-ethyl-2-adamantyl 5-norbornene-2-carboxylate, 5-norbornene-2-carboxylic acid 1- (4-methylcyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1- (4-hydroxycyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1-methyl-1- (4 -Oxocyclohexyl) ethyl, 5-norbornene-2-carboxylic acid 1- (1-adap Pentyl) -1-methylethyl and the like.

  The content of the structural unit derived from the monomer represented by the formula (a1-3) in the resin is usually 10 to 95 mol%, preferably 15 to 90 mol%, more preferably in all units of the resin. Is 20 to 85 mol%.

［式（ａ１−４）中、
Ｒ¹⁰は、水素原子、ハロゲン原子又はハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。
Ｒ¹¹は、それぞれ独立に、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数２〜４のアシル基、炭素数２〜４のアシルオキシ基、アクリロイル基又はメタクリロイル基を表す。
ｌａは０〜４の整数を表す。ｌａが２以上の整数である場合、複数のＲ¹¹は同一であっても異なってもよい。
Ｒ¹²及びＲ¹³はそれぞれ独立に、水素原子又は炭素数１〜１２の炭化水素基を表す。
Ｘ^ａ２は、単結合又は置換基を有していてもよい２価の炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^ｃ）−で置き換わっていてもよい。Ｒ^ｃは、水素原子又は炭素数１〜６のアルキル基を表す。
Ｙ^ａ３は、炭素数１〜１２の脂肪族炭化水素基、炭素数３〜１８の飽和炭化水素基又は炭素数６〜１８の芳香族炭化水素基であり、該脂肪族炭化水素基、飽和炭化水素基及び芳香族炭化水素基は、置換基を有していてもよい。］ Examples of the monomer having an acid labile group and a carbon-carbon double bond include a monomer (a1-4) represented by the formula (a1-4).

[In the formula (a1-4),
R ¹⁰ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
R ¹¹ each independently represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, Represents an acryloyl group or a methacryloyl group.
la represents an integer of 0 to 4. When la is an integer of 2 or more, the plurality of R ¹¹ may be the same or different.
R ¹² and R ¹³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.
X ^a2 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —CO—, — O—, —S—, —SO ₂ — or —N (R ^c ) — may be substituted. R ^c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
Y ^a3 is an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a saturated hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the aliphatic hydrocarbon group, saturated hydrocarbon group The hydrogen group and the aromatic hydrocarbon group may have a substituent. ]

Examples of the alkyl group that may have a halogen atom include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, and a perfluoropentyl group. Perfluorohexyl group, perchloromethyl group, perbromomethyl group, periodomethyl group and the like.
Examples of the acyl group include an acetyl group, a propionyl group, and a butyryl group.
Examples of the acyloxy group include acetyloxy, propionyloxy, butyryloxy and the like.
Examples of the hydrocarbon group include an aliphatic hydrocarbon group, a saturated hydrocarbon group, and an aromatic hydrocarbon group.

In formula (a1-4), the alkyl group of R ¹⁰ and R ¹¹ preferably has 1 to 4 carbon atoms, more preferably 1 or 2 carbon atoms, and particularly preferably a methyl group.
As the alkoxy group for R ¹¹ , C 1 or 2 is more preferable, and a methoxy group is particularly preferable.
Examples of the hydrocarbon group for R ¹² and R ¹³ include isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, 2-ethylhexyl group, cyclohexyl group, adamantyl group, A 2-alkyl-2-adamantyl group, a 1- (1-adamantyl) -1-alkyl group, an isobornyl group, and the like are preferable.
Examples of the group that may be substituted with the groups X ^a2 and Y ^a3 include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and an acyl group having 2 to 4 carbon atoms. And an acyloxy group having 2 to 4 carbon atoms. Of these, a hydroxy group is preferable.

  As a monomer (a1-4), the following monomers are mentioned, for example.

  The content of the structural unit derived from the monomer represented by the formula (a1-4) in the resin is usually 10 to 95 mol%, preferably 15 to 90 mol%, more preferably in all units of the resin. Is 20 to 85 mol%.

Furthermore, a monomer that derives another structural unit having an acid labile group (1) and a carbon-carbon double bond in the molecule may be used.
Examples of such other acid labile monomers include the following monomers.

  When the resin (A) has a structural unit derived from another acid labile monomer, the content is preferably 10 to 95 mol% with respect to the total structural unit (100 mol%) of the resin (A). More preferably, it is 15-90 mol%, More preferably, it is 20-85 mol%.

The resin (A) is preferably composed of a compound represented by the formula (I), a monomer (a1) having an acid labile group, and a monomer having no acid labile group (hereinafter referred to as “acid stable”). It may be referred to as a “monomer”). An acid stable monomer may be used individually by 1 type, and may use 2 or more types together.
When the resin (A) is a copolymer of a compound represented by formula (I), a monomer (a1) having an acid labile group and an acid stable monomer, a monomer having an acid labile group ( The structural unit derived from a1) is preferably 10 to 80 mol%, more preferably 20 to 60 mol%, based on 100 mol% of all structural units. Further, the structural unit derived from the monomer having an adamantyl group (particularly the monomer (a1-1) having an acid labile group) is converted to 15 mol per 100 mol% of the monomer (a1) having an acid labile group. It is preferable to set it as mol% or more. When the ratio of the monomer having an adamantyl group increases, the dry etching resistance of the resist is improved.

<Acid stable monomer>
As the acid stable monomer, those having a hydroxy group or a lactone ring are preferred. Derived from an acid stable monomer having a hydroxy group (hereinafter referred to as “acid stable monomer having a hydroxy group (a2)”) or an acid stable monomer having a lactone ring (hereinafter referred to as “acid stable monomer having a lactone ring (a3)”) If a resin having a structural unit to be used is used, the resolution of the resist and the adhesion to the substrate can be improved.

<Acid-stable monomer having a hydroxy group (a2)>
When the resist composition is used for KrF excimer laser exposure (248 nm), high energy beam exposure such as electron beam or EUV light, the acid-stable monomer (a2) having a hydroxy group has an acid having a phenolic hydroxyl group which is a hydroxystyrene. It is preferable to use a stable monomer (a2-0). When using short wavelength ArF excimer laser exposure (193 nm) or the like, an acid stable monomer having a hydroxyadamantyl group represented by formula (a2-1) should be used as the acid stable monomer having a hydroxy group (a2). Is preferred. The acid-stable monomer (a2) having a hydroxy group may be used alone or in combination of two or more.

  Examples of the monomer (a2-0) having a phenolic hydroxyl group include styrene monomers such as p- or m-hydroxystyrene represented by the formula (a2-0).

［式（ａ２−０）中、
Ｒ^８は、水素原子、ハロゲン原子又はハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。
Ｒ^９は、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数２〜４のアシル基、炭素数２〜４のアシルオキシ基、アクリロイル基又はメタクリロイル基を表す。
ｍａは０〜４の整数を表す。ｍａが２以上の整数である場合、複数のＲ^９は同一であっても異なってもよい。］

[In the formula (a2-0),
R ⁸ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
R ⁹ is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an acryloyl group, or methacryloyl. Represents a group.
ma represents an integer of 0 to 4. When ma is an integer of 2 or more, the plurality of R ⁹ may be the same or different. ]

As the alkyl group for R ^8, an alkyl group having 1 to 4 carbon atoms is preferable, an alkyl group having 1 or 2 carbon atoms is more preferable, and a methyl group is particularly preferable.
Moreover, as an alkoxy group, a C1-C4 alkoxy group is preferable, a C1-C2 alkoxy group is more preferable, and a methoxy group is especially preferable.
ma is preferably 0 to 2, more preferably 0 or 1, and particularly preferably 0.

When obtaining a copolymer resin having a structural unit derived from a monomer having such a phenolic hydroxyl group, the corresponding (meth) acrylic acid ester monomer, acetoxystyrene, and styrene are radically polymerized and then deacetylated with an acid. Can be obtained.
Examples of the monomer having a phenolic hydroxyl group include the following monomers.

  Of the above monomers, 4-hydroxystyrene or 4-hydroxy-α-methylstyrene is particularly preferred.

  The content of the structural unit derived from the monomer represented by the formula (a2-0) in the resin is usually from 5 to 90 mol%, preferably from 10 to 85 mol%, more preferably in all units of the resin. Is 15 to 80 mol%.

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。
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 acid stable monomer having a hydroxyadamantyl group include a monomer represented by the formula (a2-1).

In formula (a2-1),
L ^a3 represents —O— or —O— (CH ₂ ) _k2 —CO—O—,
k2 represents an integer of 1 to 7.
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 an acid stable monomer (a2-1) which has a hydroxyadamantyl group, the following are mentioned, for example. Among them, 3-hydroxy-1-adamantyl (meth) acrylate, 3,5-dihydroxy-1-adamantyl (meth) acrylate, and 1- (3,5-dihydroxy-1-adamantyloxycarbonyl) methyl (meth) acrylate are Preferably, 3-hydroxy-1-adamantyl (meth) acrylate and 3,5-dihydroxy-1-adamantyl (meth) acrylate are more preferable, 3-hydroxy-1-adamantyl methacrylate and 3,5-dihydroxy-1-adamantyl methacrylate Is more preferable.

  The content of the structural unit derived from the monomer represented by the formula (a2-1) in the resin is usually from 3 to 45 mol%, preferably from 5 to 40 mol%, more preferably in all units of the resin. Is 5 to 35 mol%.

<Acid-stable monomer having a lactone ring (a3)>
The lactone ring possessed by the acid stable monomer (a3) may be, for example, a monocyclic ring such as a β-propiolactone ring, γ-butyrolactone ring, or δ-valerolactone ring, or a monocyclic lactone ring and another ring. The condensed ring may be used. Among these lactone rings, a γ-butyrolactone ring and a condensed ring of a γ-butyrolactone ring and another ring are preferable.

  The acid-stable monomer (a3) having a lactone ring is preferably represented by the formula (a3-1), the formula (a3-2) or the formula (a3-3). These 1 type may be used independently and may use 2 or more types together.

式（ａ３−１）〜式（ａ３−３）中、
Ｌ^a4〜Ｌ^a6は、それぞれ独立に、−Ｏ−又は−Ｏ−（ＣＨ₂）_k3−ＣＯ−Ｏ−を表す。
ｋ３は１〜７の整数を表す。
Ｒ^a18〜Ｒ^a20は、それぞれ独立に、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。
Ｒ^a22及びＲ^a23は、それぞれ独立に、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及びｒ１は、それぞれ独立に０〜３の整数を表す。ｐ１、ｑ１又はｒ１が２以上のとき、それぞれ、複数のＲ^a21、Ｒ^a22又はＲ^a23は、互いに同一でも異なってもよい。

In formula (a3-1) to formula (a3-3),
L ^{a4 to} L ^a6 each independently represent —O— or —O— (CH ₂ ) _k3 —CO—O—.
k3 represents an integer of 1 to 7.
R ^{a18 to} R ^a20 each independently 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.
R ^a22 and R ^a23 each independently represent a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
q1 and r1 each independently represents an integer of 0 to 3. When p1, q1 or r1 is 2 or more, a plurality of R ^a21 , R ^a22 or R ^a23 may be the same as or different from each other.

In the formula (a3-1) to the formula (a3-3), examples of L ^{a4 to} L ^a6 include those described for L ^a3 .
L ^{a4 to} L ^a6 are each independently preferably —O—, —O— (CH ₂ ) _d1 —CO—O— (wherein d1 is an integer of 1 to 4), more preferably -O-. However, —O— and the like enumerated in L ^{a4 to} L ^a6 mean that they are bonded to —CO— of the formula (a3-1) to the formula (a3-3) on the left side and to the lactone ring on the right side. To do.
R ^{a18 to} R ^a21 are preferably methyl groups.
R ^a22 and R ^a23 are each independently preferably a carboxy group, a cyano group or a methyl group.
p1 to r1 are each independently preferably 0 to 2, more preferably 0 or 1.

  Examples of the acid stable monomer (a3-1) having a γ-butyrolactone ring include the following.

  Examples of the acid stable monomer (a3-2) having a condensed ring of γ-butyrolactone ring and norbornane ring include the following.

  Examples of the acid stable monomer (a3-3) having a condensed ring of γ-butyrolactone ring and cyclohexane ring include the following.

Among acid-stable monomers (a3) having a lactone ring, (meth) acrylic acid (5-oxo-4-oxatricyclo [4.2.1.0 ^3,7 ] nonan-2-yl, (meth) acrylic Acid tetrahydro-2-oxo-3-furyl, 2- (5-oxo-4-oxatricyclo [4.2.1.0 ^3,7 ] nonan-2-yloxy) -2-oxoethyl (meth) acrylate Are preferred, and those in the form of methacrylate are more preferred.

  Content of the structural unit derived from the monomer represented by Formula (a3-1), Formula (a3-2) or Formula (a3-3) in the resin is usually 5 to 70 mol% in all units of the resin. Yes, preferably 10 to 65 mol%, more preferably 10 to 60 mol%.

<Other acid stable monomers (a4)>
Examples of the other acid stable monomer (a4) include maleic anhydride represented by formula (a4-1), itaconic anhydride represented by formula (a4-2), and formula (a4-3). And acid-stable monomers having a norbornene ring.

式（ａ４−３）中、
Ｒ^a25及びＲ^a26は、それぞれ独立に、水素原子、置換基（例えば、ヒドロキシ基）を有していてもよい炭素数１〜３の脂肪族炭化水素基、シアノ基、カルボキシ基又は基−ＣＯＯＲ^a27を表すか、或いはＲ^a25及びＲ^a26は互いに結合して−ＣＯ−Ｏ−ＣＯ−を形成し、
Ｒ^a27は、炭素数１〜３６の脂肪族炭化水素基又は炭素数３〜３６の飽和炭化水素基を表し、脂肪族炭化水素基及び飽和炭化水素基の−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。但し−ＣＯＯＲ^a27が酸不安定基となるものは除く（即ちＲ^a27は、３級炭素原子が−Ｏ−と結合するものを含まない）。

In formula (a4-3),
R ^a25 and R ^a26 each independently represent a hydrogen atom, an aliphatic hydrocarbon group having 1 to 3 carbon atoms which may have a substituent (for example, a hydroxy group), a cyano group, a carboxy group, or a group —COOR. ^{a 27} or R ^a25 and R ^a26 combine with each other to form —CO—O—CO—;
R ^a27 represents an aliphatic hydrocarbon group having 1 to 36 carbon atoms or a saturated hydrocarbon group having 3 to 36 carbon atoms, and —CH ₂ — of the aliphatic hydrocarbon group and the saturated hydrocarbon group is —O— or It may be replaced by -CO-. However, those in which —COOR ^a27 is an acid labile group are excluded (that is, R ^a27 does not include those in which a tertiary carbon atom is bonded to —O—).

^Examples of the aliphatic hydrocarbon group which may have a substituent for R ^a25 and R ^a26 include a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, and a 2-hydroxyethyl group.
The aliphatic hydrocarbon group for R ^a27 preferably has 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms. The saturated hydrocarbon group preferably has 4 to 36 carbon atoms, more preferably 4 to 12 carbon atoms.
^Examples of R ^a27 include a methyl group, an ethyl group, a propyl group, a 2-oxo-oxolan-3-yl group, and a 2-oxo-oxolan-4-yl group.

  Examples of the acid-stable monomer (a4-3) having a norbornene ring include 2-norbornene, 2-hydroxy-5-norbornene, 5-norbornene-2-carboxylic acid, methyl 5-norbornene-2-carboxylate, 5- Examples include norbornene-2-carboxylic acid 2-hydroxy-1-ethyl, 5-norbornene-2-methanol, and 5-norbornene-2,3-dicarboxylic acid anhydride.

  Content of the structural unit derived from the monomer represented by Formula (a4-1), Formula (a4-2), or Formula (a4-3) in the resin is usually 2 to 40 mol% in all units of the resin. Yes, preferably 3-30 mol%, more preferably 5-20 mol%.

  Preferred resin (A) is at least a compound represented by the formula (I), a monomer (a1) having an acid labile group, an acid stable monomer (a2) having a hydroxy group, and / or an acid having a lactone ring. It is a copolymer obtained by polymerizing the stable monomer (a3). In this preferred copolymer, the monomer (a1) having an acid labile group is more preferably at least one of a monomer (a1-1) having an adamantyl group and a monomer (a1-2) having a cyclohexyl group. A species (more preferably a monomer (a1-1) having an adamantyl group), and an acid stable monomer (a2) having a hydroxy group, preferably an acid stable monomer (a2-1) having a hydroxyadamantyl group, and a lactone The acid-stable monomer (a3) having a ring is more preferably an acid-stable monomer (a3-1) having a γ-butyrolactone ring and an acid-stable monomer (a3-2) having a condensed ring of a γ-butyrolactone ring and a norbornane ring At least one of the following. Resin (A) can be manufactured by a well-known polymerization method (for example, radical polymerization method).

The weight average molecular weight of the resin (A) is preferably 2,500 or more (more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less).
It is preferable that content of resin (A) is 80 mass% or more in solid content of a composition. 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 content of the resin (A) relative thereto can be measured by a known analysis means such as liquid chromatography or gas chromatography.

<Resist composition>
The resist composition of the present invention contains the resin (A) described above, that is, a resin having a structural unit derived from the compound represented by the formula (I), and an acid generator.
<Acid generator (hereinafter sometimes referred to as "acid generator (B)")>
The acid generator (B) is classified into a nonionic type and an ionic type, and any of them can be used in the resist composition of the present invention.
Nonionic acid generators include organic halides, sulfonate esters (for example, 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, N-sulfonyloxyimide, sulfonyloxyketone, DNQ 4- Sulfonate), sulfones (for example, disulfone, ketosulfone, sulfonyldiazomethane) and the like.
The ionic acid generator is typically an onium salt containing an onium cation (for example, diazonium salt, phosphonium salt, sulfonium salt, iodonium salt).
Examples of the anion of the onium salt include a sulfonate anion, a sulfonylimide anion, and a sulfonylmethide anion.

  As the acid generator (B), not only an acid generator (particularly a photoacid generator) used in the resist field, but also a photoinitiator for photocationic polymerization, a photodecolorant or a photochromic agent for dyes, Known compounds that generate an acid by radiation (light) and mixtures thereof can also be used as appropriate. For example, JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, Acid by radiation as described in 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, etc. Can be used.

  The acid generator (B) is preferably a fluorine-containing acid generator, more preferably a sulfonate represented by the formula (B1).

［式（Ｂ１）中、
Ｑ¹及びＱ²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２価の炭素数１〜１７の飽和炭化水素基を表し、前記２価の飽和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。
Ｙは、置換基を有していてもよい炭素数１〜１８の脂肪族炭化水素基又は置換基を有していてもよい炭素数３〜１８の飽和炭化水素基を表し、前記脂肪族炭化水素基及び前記飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＳＯ_２−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。］

[In the formula (B1),
Q ¹ and Q ² each independently represents 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 —CH ₂ — contained in the divalent saturated hydrocarbon group is replaced by —O— or —CO—. May be.
Y represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent or a saturated hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, and the aliphatic carbonization —CH ₂ — contained in the hydrogen group and the saturated hydrocarbon group may be replaced by —O—, —SO ₂ — or —CO—.
Z ⁺ represents an organic cation. ]

Examples of the perfluoroalkyl group include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. It is done.
In formula (B1), Q ¹ and Q ² are each independently preferably a perfluoromethyl group or a fluorine atom, more preferably a fluorine atom.

Examples of the divalent saturated hydrocarbon group include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic alicyclic hydrocarbon group, and two or more of these groups are selected. It may be a combination.
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, methylidene group, ethylidene group, propylidene group, 2-propylidene group;
An alkyl group (particularly an alkyl group having 1 to 4 carbon atoms, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, etc.) is added to the linear alkanediyl. Those having a side chain, for example, 1-methyl-1,3-propylene group, 2-methyl-1,3-propylene group, 2-methyl-1,2-propylene group, 1-methyl-1,4-propylene group Branched alkanediyl such as butylene group, 2-methyl-1,4-butylene group;
Monocyclic alicyclic hydrocarbons that are cycloalkanediyl groups such as 1,3-cyclobutylene group, 1,3-cyclopentylene group, 1,4-cyclohexylene group, 1,5-cyclooctylene group, etc. Group;
Examples thereof include polycyclic alicyclic hydrocarbon groups such as 1,4-norbornylene group, 2,5-norbornylene group, 1,5-adamantylene group, 2,6-adamantylene group and the like.

Examples of the group in which —CH ₂ — contained in the saturated hydrocarbon group of L ^b1 is replaced by —O— or —CO— include formula (b1-1) to formula (b1-6). L ^b1 is preferably any one of formulas (b1-1) to (b1-4), more preferably formula (b1-1) or formula (b1-2). Incidentally, the formula (b1-1) ~ formula (b1-6) are described together the left and right in the equation (B1), the left ^{C (Q 1) (Q 2} ) - bound to, the right side Combines with -Y. The same applies to specific examples of the following formulas (b1-1) to (b1-6).

式（ｂ１−１）〜式（ｂ１−６）中、
Ｌ^b2は、単結合又は炭素数１〜１５の飽和炭化水素基を表す。
Ｌ^b3は、単結合又は炭素数１〜１２の飽和炭化水素基を表す。
Ｌ^b4は、炭素数１〜１３の飽和炭化水素基を表す。但しＬ^b3及びＬ^b4の炭素数上限は１３である。
Ｌ^b5は、炭素数１〜１５の飽和炭化水素基を表す。
Ｌ^b6及びＬ^b7は、それぞれ独立に、炭素数１〜１５の飽和炭化水素基を表す。但しＬ^b6及びＬ^b7の炭素数上限は１６である。
Ｌ^b8は、炭素数１〜１４の飽和炭化水素基を表す。
Ｌ^b9は、炭素数１〜１１の飽和炭化水素基を表す。
Ｌ^b10は、炭素数１〜１１の飽和炭化水素基を表す。但しＬ^ｂ９及びＬ^ｂ１０の炭素数上限は１２である。

In formula (b1-1) to formula (b1-6),
L ^b2 represents a single bond or a saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^b3 represents a single bond or a saturated hydrocarbon group having 1 to 12 carbon atoms.
L ^b4 represents a saturated hydrocarbon group having 1 to 13 carbon atoms. However, the upper limit of the carbon number of L ^b3 and L ^b4 is 13.
L ^b5 represents a saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^b6 and L ^b7 each independently represent a saturated hydrocarbon group having 1 to 15 carbon atoms. However, the upper limit of the carbon number of L ^b6 and L ^b7 is 16.
L ^b8 represents a saturated hydrocarbon group having 1 to 14 carbon atoms.
L ^b9 represents a saturated hydrocarbon group having 1 to 11 carbon atoms.
L ^b10 represents a saturated hydrocarbon group having 1 to 11 carbon atoms. However, the upper limit of the carbon number of L ^b9 and L ^b10 is 12.

The saturated hydrocarbon group in L ^{b2 to} L ^b9 is preferably an alkanediyl group, and the saturated hydrocarbon group in L ^b10 is preferably an alkanediyl group or a divalent alicyclic hydrocarbon group having 3 to 10 carbon atoms. Alkanediyl group, cyclohexyl group and adamantyl group are more preferable.
Among these, a divalent group represented by the formula (b1-1) is preferable, and a divalent group represented by the formula (b1-1) in which L ^b2 is a single bond or —CH ₂ — is more preferable.

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

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

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

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

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

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

The saturated hydrocarbon group for L ^b1 may have a substituent. Examples of the substituent include a halogen atom, a hydroxy group, a carboxy group, an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, an acyl group having 2 to 4 carbon atoms, and a glycidyloxy group. Is mentioned.

As the aliphatic hydrocarbon group for Y, an alkyl group having 1 to 6 carbon atoms is preferable.
Examples of the substituent of the aliphatic hydrocarbon group and saturated hydrocarbon group of Y include, for example, a halogen atom (excluding a fluorine atom), a hydroxy group, an oxo group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, and a hydroxy group Containing C1-C12 aliphatic hydrocarbon group, C3-C16 saturated hydrocarbon group, C1-C12 alkoxy group, C6-C18 aromatic hydrocarbon group, C7-C21 An aralkyl group, an acyl group having 2 to 4 carbon atoms, a glycidyloxy group, or — (CH ₂ ) _j2 —O—CO—R ^b1 group (wherein R ^b1 is an aliphatic hydrocarbon group having 1 to 16 carbon atoms) Represents a saturated hydrocarbon group having 3 to 16 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, j2 represents an integer of 0 to 4).
The aliphatic hydrocarbon group, saturated hydrocarbon group, aromatic hydrocarbon group, aralkyl group, and the like, which are substituents for Y, may further have a substituent. Examples of the substituent include an alkyl group, a halogen atom, a hydroxy group, and an oxo group.
Examples of the hydroxy group-containing aliphatic hydrocarbon group include a hydroxymethyl group and a hydroxyethyl group.
Examples of the group in which —CH ₂ — in the aliphatic hydrocarbon group and saturated hydrocarbon group are replaced by —O—, —SO ₂ — or —CO— include, for example, an ether bond or a cyclic ether group (—CH ₂ — is — A group substituted by O-), a saturated hydrocarbon group having an oxo group (a group in which -CH ₂ -is replaced by -CO-), and a sultone ring group (two adjacent -CH _2- groups are each -O- Or a group substituted by —SO ₂ —) or a lactone ring group (a group in which two adjacent —CH ₂ — are each replaced by —O— or —CO—).

In particular, examples of the saturated hydrocarbon group for Y include groups represented by formulas (Y1) to (Y26).

  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 Y, which is a saturated hydrocarbon group substituted with an aliphatic hydrocarbon group, include the following.

  Examples of Y that is a saturated hydrocarbon group substituted with a hydroxy group or a hydroxy group-containing aliphatic hydrocarbon group include the following.

  Examples of Y that is a saturated hydrocarbon group substituted with an aromatic hydrocarbon group include the following.

Examples of Y that is a saturated hydrocarbon group in which the — (CH ₂ ) _j2 —O—CO—R ^b1 group is substituted include the following.

Ｙは、好ましくは置換基（例えば、オキソ基等）を有していてもよいアダマンチル基であり、より好ましくはアダマンチル基又はオキソアダマンチル基である。

Y is preferably an adamantyl group which may have a substituent (for example, an oxo group or the like), more preferably an adamantyl group or an oxoadamantyl group.

Saturated hydrocarbon substituted with sulfonate anion or aliphatic hydrocarbon group containing Y which is an aliphatic hydrocarbon group or an unsubstituted saturated hydrocarbon group and a divalent group represented by formula (b1-1) Examples of the sulfonate anion containing the group Y and the divalent group represented by the formula (b1-1) include the following.

Examples of the sulfonate anion containing Y which is a saturated hydrocarbon group substituted with — (CH ₂ ) _j2 —O—CO—R ^b1 group and a divalent group represented by the formula (b1-1) include: The following are mentioned.

  Examples of the sulfonate anion containing Y which is a saturated hydrocarbon group substituted with a hydroxy group or a hydroxy group-containing aliphatic hydrocarbon group and a divalent group represented by the formula (b1-1) include the following: Is mentioned.

  Examples of the sulfonate anion containing Y which is a saturated hydrocarbon group substituted with an aromatic hydrocarbon group or an aralkyl group and a divalent group represented by the formula (b1-1) include the following. .

Examples of the sulfonate anion containing Y which is a cyclic ether and the divalent group represented by the formula (b1-1) include the following.

Examples of the sulfonate anion containing Y which is a lactone ring and the divalent group represented by the formula (b1-1) include the following.

  Examples of the sulfonate anion containing Y which is an alicyclic hydrocarbon having an oxo group and a divalent group represented by the formula (b1-1) include the following.

Examples of the sulfonate anion containing Y which is a sultone ring and the divalent group represented by the formula (b1-1) include the following.

Saturated hydrocarbon substituted with sulfonate anion or aliphatic hydrocarbon group containing Y which is an aliphatic hydrocarbon group or an unsubstituted saturated hydrocarbon group and a divalent group represented by formula (b1-2) Examples of the sulfonate anion containing the group Y and the divalent group represented by the formula (b1-2) include the following.

Examples of the sulfonate anion containing Y which is a saturated hydrocarbon group substituted with — (CH ₂ ) _j2 —O—CO—R ^b1 group and a divalent group represented by the formula (b1-2) include: The following are mentioned.

  Examples of the sulfonate anion containing Y which is a saturated hydrocarbon group substituted with a hydroxy group or a hydroxy group-containing aliphatic hydrocarbon group and a divalent group represented by the formula (b1-2) include the following: Is mentioned.

  Examples of the sulfonate anion containing Y, which is a saturated hydrocarbon group substituted with an aromatic hydrocarbon group, and a divalent group represented by the formula (b1-2) include the following.

  Examples of the sulfonate anion containing Y which is a cyclic ether and the divalent group represented by the formula (b1-2) include the following.

  Examples of the sulfonate anion containing Y which is a lactone ring and the divalent group represented by the formula (b1-2) include the following.

  Examples of the sulfonate anion containing Y having an oxo group and the divalent group represented by the formula (b1-2) include the following.

  Examples of the sulfonate anion containing Y which is a sultone ring and the divalent group represented by the formula (b1-2) include the following.

  Y which is a saturated hydrocarbon group substituted with a sulfonate anion or an aliphatic hydrocarbon group containing an aliphatic hydrocarbon group or an unsubstituted Y and a divalent group represented by the formula (b1-3) Examples of the sulfonate anion containing the divalent group represented by (b1-3) include the following.

  Examples of the sulfonate anion containing Y, which is a saturated hydrocarbon group substituted with an alkoxy group, and the divalent group represented by the formula (b1-3) include the following.

  Examples of the sulfonate anion containing Y which is a saturated hydrocarbon group substituted with a hydroxy group or a hydroxy group-containing aliphatic hydrocarbon group and a divalent group represented by the formula (b1-3) include the following: Is mentioned.

  Examples of the sulfonate anion containing Y having an oxo group and the divalent group represented by the formula (b1-3) include the following.

  Examples of the sulfonate anion containing Y, which is a saturated hydrocarbon group substituted with an aliphatic hydrocarbon group, and a divalent group represented by the formula (b1-4) include the following.

  Examples of the sulfonate anion containing Y which is a saturated hydrocarbon group substituted with an alkoxy group and the divalent group represented by the formula (b1-4) include the following.

  Examples of the sulfonate anion containing Y which is a saturated hydrocarbon group substituted with a hydroxy group or a hydroxy group-containing aliphatic hydrocarbon group and a divalent group represented by the formula (b1-4) include the following: Is mentioned.

  Examples of the sulfonate anion containing Y which is a saturated hydrocarbon group having an oxo group and a divalent group represented by the formula (b1-4) include the following.

Examples of the sulfonate anion in the salt represented by the formula (B1) include the following formulas (b1-1-1) to (b1-1-9) in which the substituent L ^b1 is the formula (b1-1). An anion represented by In the following formulae, the definition of the substituent has the same meaning as described above, and the substituents R ^b2 and R ^b3 each independently represent an aliphatic hydrocarbon group having 1 to 4 carbon atoms (preferably a methyl group). .

Among them, the anion represented by the formula (b1-1-1) ~ formula (b1-1-9), those ^{Q 1} and ^{Q 2} is fluorine atom is more preferable. Further, the following sulfonate anions having a divalent group represented by the formula (b1-1) are more preferable.

  Examples of the cation contained in the acid generator (B) include an onium cation such as a sulfonium cation, an iodonium cation, an ammonium cation, a benzothiazolium cation, and a phosphonium cation. Among these, a sulfonium cation and an iodonium cation are preferable, and an arylsulfonium cation is more preferable.

Z ⁺ in formula (B1) is preferably represented by any of formula (b2-1) to formula (b2-4).

In these formulas (b2-1) to (b2-4),
R ^{b4 to} R ^b6 each independently represents an aliphatic hydrocarbon group having 1 to 30 carbon atoms, a saturated hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. The aliphatic hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the saturated hydrocarbon group includes a halogen atom, a carbon atom The aromatic hydrocarbon group may be substituted with an acyl group of 2 to 4 or a glycidyloxy group, and the aromatic hydrocarbon group includes a halogen atom, a hydroxy group, an aliphatic hydrocarbon group of 1 to 36 carbon atoms, and 3 to 36 carbon atoms May be substituted with a saturated hydrocarbon group or an alkoxy group having 1 to 12 carbon atoms.

R ^b7 and R ^b8 each independently represent a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
m2 and n2 each independently represent an integer of 0 to 5.

R ^b9 and R ^b10 each independently represent an aliphatic hydrocarbon group having 1 to 36 carbon atoms or a saturated hydrocarbon group having 3 to 36 carbon atoms.
R ^b11 represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 36 carbon atoms, a saturated hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.
The aliphatic hydrocarbon group of R ^{b9 to} R ^b11 preferably has 1 to 12 carbon atoms, and the saturated hydrocarbon group preferably has 3 to 36 carbon atoms, more preferably 4 to 12 carbon atoms.
R ^b12 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a saturated hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. The aromatic hydrocarbon group may be substituted with an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, a saturated hydrocarbon group having 3 to 18 carbon atoms, or an alkylcarbonyloxy group. Good.
R ^b9 and R ^b10 may be bonded to each other together with the sulfur atom to which they are bonded to form a 3- to 12-membered ring (preferably a 3- to 7-membered ring), and R ^b11 and R ^b12 are , And -CH-CO- to which they are bonded may form a 3- to 12-membered ring (preferably a 3- to 7-membered ring).

R ^{b13 to} R ^b18 each independently represent a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
L ^b11 represents -S- or -O-.
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 any of o2 to t2 is 2, any of the plurality of R ^{b13 to} R ^b18 may be the same as or different from each other.

  Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, an n-propylcarbonyloxy group, an isopropylcarbonyloxy group, an n-butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, Examples thereof include a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, and a 2-ethylhexylcarbonyloxy group.

Preferred aliphatic hydrocarbon groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, octyl and 2-ethylhexyl. It is.
Preferred saturated hydrocarbon groups are cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclodecyl, 2-alkyl-2-adamantyl, 1- (1-adamantyl) -1-alkyl, and An isobornyl group.
Preferred aromatic hydrocarbon groups are phenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-tert-butylphenyl group, 4-cyclohexylphenyl group, 4-methoxyphenyl group, biphenylyl group, naphthyl group. It is.
Examples of the aliphatic hydrocarbon group (aralkyl group) whose substituent is an aromatic hydrocarbon group include a benzyl group.
Examples of the ring formed by R ^b9 and R ^b10 include a thiolane-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, and a 1,4-oxathian-4-ium ring.
^Examples of the ring formed by R ^b11 and R ^b12 include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

  Among the cations (b2-1) to (b2-4), the cation (b2-1) is preferable, the cation represented by the formula (b2-1-1) is more preferable, and the triphenylsulfonium cation (formula (b2) In (1-1), v2 = w2 = x2 = 0) is more preferable.

式（ｂ２−１−１）中、
Ｒ^b19〜Ｒ^b21は、それぞれ独立に、ハロゲン原子（より好ましくはフッ素原子）、ヒドロキシ基、炭素数１〜３６の脂肪族炭化水素基、炭素数３〜３６の飽和炭化水素基又は炭素数１〜１２のアルコキシ基を表す。
脂肪族炭化水素基は、好ましくは炭素数１〜１２であり、飽和炭化水素基は、好ましくは炭素数４〜３６である。
前記脂肪族炭化水素基は、ヒドロキシ基、炭素数１〜１２のアルコキシ基又は炭素数６〜１８の芳香族炭化水素基で置換されていてもよい。
前記飽和炭化水素基は、ハロゲン原子、炭素数２〜４のアシル基又はグリシジルオキシ基で置換されていてもよい。
ｖ２〜ｘ２は、それぞれ独立に０〜５の整数（好ましくは０又は１）を表す。ｖ２〜ｘ２のいずれかが２以上のとき、それぞれ、複数のＲ^b19〜Ｒ^b21のいずれかは、互いに同一でも異なってもよい。
なかでも、Ｒ^b19〜Ｒ^b21は、それぞれ独立に、好ましくは、ハロゲン原子（より好ましくはフッ素原子）、ヒドロキシ基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基である。

In formula (b2-1-1),
R ^{b19 to} R ^b21 each independently represent a halogen atom (more preferably a fluorine atom), a hydroxy group, an aliphatic hydrocarbon group having 1 to 36 carbon atoms, a saturated hydrocarbon group having 3 to 36 carbon atoms, or 1 carbon atom. Represents an alkoxy group of ˜12.
The aliphatic hydrocarbon group preferably has 1 to 12 carbon atoms, and the saturated hydrocarbon group preferably has 4 to 36 carbon atoms.
The aliphatic hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.
The saturated hydrocarbon group may be substituted with a halogen atom, an acyl group having 2 to 4 carbon atoms, or a glycidyloxy group.
v2 to x2 each independently represents an integer of 0 to 5 (preferably 0 or 1). When any one of v2 to x2 is 2 or more, any one of the plurality of R ^{b19 to} R ^b21 may be the same as or different from each other.
Among these, R ^{b19 to} R ^b21 are preferably each independently a halogen atom (more preferably a fluorine atom), a hydroxy group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.

Specific examples of the cation (b2-1-1) include the following.

Specific examples of the cation (b2-2) include the following.

Specific examples of the cation (b2-3) include the following.

Specific examples of the cation (b2-4) include the following.

  The acid generator (B1) is a combination of the above-described sulfonate anion and organic cation. The above-mentioned anion and cation can be arbitrarily combined, but any one of anion (b1-1-1) to anion (b1-1-9) and a cation (b2-1-1), and an anion ( A combination of any one of b1-1-3) to (b1-1-5) and a cation (b2-3) is preferable.

  Preferred acid generators (B1) are those represented by formulas (B1-1) to (B1-17), and among these, acid generators (B1-1) and (B1) containing a triphenylsulfonium cation. -2), (B1-6), (B1-11), (B1-12), (B1-13) and (B1-14) are more preferred.

  The content of the acid generator (B) is preferably 1 part by mass or more (more preferably 3 parts by mass or more), preferably 30 parts by mass or less (more preferably 25 parts by mass) with respect to 100 parts by mass of the resin (A). Part or less).

<Basic compound (hereinafter sometimes referred to as “basic compound (C)”)>
The resist composition of the present invention suitably contains a basic compound (C). The content of the basic compound (C) is preferably about 0.01 to 1% by mass based on the solid content of the resist composition.

  The basic compound (C) is preferably a basic nitrogen-containing organic compound (for example, amine or ammonium salt). The amine may be an aliphatic amine or an aromatic amine. As the aliphatic amine, any of primary amine, secondary amine and tertiary amine can be used. The aromatic amine may be any of an amino group bonded to an aromatic ring such as aniline and a heteroaromatic amine such as pyridine. Preferable basic compound (C) includes an aromatic amine represented by the formula (C2), particularly an aniline represented by the formula (C2-1).

Here, Ar ^c1 represents an aromatic hydrocarbon group.
R ^c5 and R ^c6 each independently represents a hydrogen atom, an aliphatic hydrocarbon group (preferably an alkyl group or a cycloalkyl group), a saturated hydrocarbon group or an aromatic hydrocarbon group.
R ^c7 represents an aliphatic hydrocarbon group (preferably an alkyl group or a cycloalkyl group), an alkoxy group, a saturated hydrocarbon group, or an aromatic hydrocarbon group.
However, the hydrogen atom of the aliphatic hydrocarbon group, alkoxy group, saturated hydrocarbon group and aromatic hydrocarbon group may be substituted with a hydroxy group, an amino group or an alkoxy group having 1 to 6 carbon atoms, and the amino group May be substituted with an alkyl group having 1 to 4 carbon atoms.
The aliphatic hydrocarbon group preferably has about 1 to 6 carbon atoms. The alkoxy group preferably has about 1 to 6 carbon atoms. The saturated hydrocarbon group preferably has about 5 to 10 carbon atoms. The aromatic hydrocarbon group preferably has about 6 to 10 carbon atoms.
m3 represents an integer of 0 to 3. When m3 is 2 or more, the plurality of R ^c7 may be the same as or different from each other.

Examples of the aromatic amine (C2) include 1-naphthylamine and 2-naphthylamine.
Examples of aniline (C2-1) include aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N, N-dimethylaniline, diphenylamine and the like.
Of these, diisopropylaniline (particularly 2,6-diisopropylaniline) is preferable.

  Moreover, as a basic compound (C), the compound represented by Formula (C3)-Formula (C11) is mentioned.

ここで、
Ｒ^c8、Ｒ^c20、Ｒ^c21、Ｒ^c23〜Ｒ^c28は、それぞれ独立に、上記Ｒ^c7で説明したいずれかの基を表す。
Ｒ^c9、Ｒ^c10、Ｒ^c11〜Ｒ^c14、Ｒ^c16〜Ｒ^c19及びＲ^c22は、それぞれ独立に、Ｒ^c5及びＲ^c6で説明したいずれかの基を表す。
Ｒ^c15は、脂肪族炭化水素基、飽和炭化水素基又はアルカノイル基を表す。
ｎ３は０〜８の整数を表す。ｎ３が２以上のとき、複数のＲ^c15は、互いに同一でも異なってもよい。
ｏ３〜ｕ３は、それぞれ独立に０〜３の整数を表す。ｏ３〜ｕ３のいずれかが２以上であるとき、それぞれ、複数のＲ^c20〜Ｒ^c28のいずれかは互いに同一でも異なってもよい。
Ｒ^c15の脂肪族炭化水素基は、好ましくは炭素数１〜６程度であり、飽和炭化水素基は、好ましくは炭素数３〜６程度であり、アルカノイル基は、好ましくは炭素数２〜６程度である。
Ｌ^c1及びＬ^c2は、それぞれ独立に、２価の脂肪族炭化水素基（好ましくはアルキレン基）、−ＣＯ−、−Ｃ（＝ＮＨ）−、−Ｃ（＝ＮＲ^c3）−、−Ｓ−、−Ｓ−Ｓ−又はこれらの組合せを表す。前記２価の脂肪族炭化水素基は、好ましくは炭素数１〜６程度である。
Ｒ^c3は、炭素数１〜４のアルキル基を表す。

here,
R ^c8 , R ^c20 , R ^c21 , R ^{c23 to} R ^c28 each independently represents any of the groups described for R ^c7 above.
R ^c9 , R ^c10 , R ^{c11 to} R ^c14 , R ^{c16 to} R ^c19 and R ^c22 each independently represent any of the groups described for R ^c5 and R ^c6 .
R ^c15 represents an aliphatic hydrocarbon group, a saturated hydrocarbon group or an alkanoyl group.
n3 represents an integer of 0 to 8. When n3 is 2 or more, the plurality of R ^c15 may be the same as or different from each other.
o3 to u3 each independently represents an integer of 0 to 3. When any of o3 to u3 is 2 or more, any of the plurality of R ^{c20 to} R ^c28 may be the same as or different from each other.
The aliphatic hydrocarbon group for R ^c15 preferably has about 1 to 6 carbon atoms, the saturated hydrocarbon group preferably has about 3 to 6 carbon atoms, and the alkanoyl group preferably has about 2 to 6 carbon atoms. It is.
L ^c1 and L ^c2 are each independently a divalent aliphatic hydrocarbon group (preferably an alkylene group), —CO—, —C (═NH) —, —C (═NR ^c3 ) —, —S—. , -SS- or a combination thereof. The divalent aliphatic hydrocarbon group preferably has about 1 to 6 carbon atoms.
R ^c3 represents an alkyl group having 1 to 4 carbon atoms.

  Examples of the alkanoyl 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 (C3) include hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, Tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctyl Amine, methyl dinonyl amine, methyl didecyl amine, ethyl dibutyl amine, ethyl dipentyl amine, ethyl di Silamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine ethylenediamine, tetramethylenediamine, hexamethylene Examples include diamine, 4,4′-diamino-1,2-diphenylethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane, and the like.

Examples of the compound (C4) include piperazine.
Examples of the compound (C5) include morpholine.
Examples of the compound (C6) include piperidine and hindered amine compounds having a piperidine skeleton described in JP-A No. 11-52575.
Examples of the compound (C7) include 2,2′-methylenebisaniline.
Examples of the compound (C8) include imidazole and 4-methylimidazole.
Examples of the compound (C9) include pyridine and 4-methylpyridine.
Examples of the compound (C10) include 1,2-di (2-pyridyl) ethane, 1,2-di (4-pyridyl) ethane, 1,2-di (2-pyridyl) ethene, and 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'-dipicolylamine and the like can be mentioned.
Examples of the compound (C11) include bipyridine.

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

<Solvent (sometimes referred to as "solvent (E)")
The resist composition of the present invention may contain the solvent (E) in an amount of 90% by mass or more in the composition. The resist composition of the present invention containing the solvent (E) is suitable for producing a thin film resist. The content of the solvent (E) is 90% by mass or more (preferably 92% by mass or more, more preferably 94% by mass or more) and 99.9% by mass or less (preferably 99% by mass or less) in the composition.
The content of the solvent (E) can be measured by a known analysis means such as liquid chromatography or gas chromatography.

  Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; ethyl lactate, butyl acetate, amyl acetate and 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 (E) may be used individually by 1 type, and may use 2 or more types together.

<Other components (hereinafter sometimes referred to as “other components (F)”)>
The resist composition of this invention may contain the other component (F) as needed. 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.

<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 mentioned above 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 using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) The process which develops the composition layer after a heating using a image development apparatus is included.

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

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

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

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

<Application>
The resist composition of the present invention is suitable as a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for EB, or a resist composition for EUV exposure machines.

Hereinafter, the present invention will be described in detail by way of examples.
In Examples and Comparative Examples, “%” and “part” representing content and use amount are based on mass unless otherwise specified.
The composition ratio of the resin (A) (copolymerization ratio of the structural unit derived from each monomer used for the production of the resin (A) to the resin (A)) is the amount of unreacted monomer in the reaction liquid after the polymerization is finished. It measured using the chromatography, and computed by calculating | requiring the monomer amount used for superposition | polymerization from the obtained result.

The weight average molecular weight is a value obtained by gel permeation chromatography (HLC-8120GPC, manufactured by Tosoh Corporation, three columns are “TSKgel Multipore HXL-M”, and the solvent is tetrahydrofuran) using polystyrene as a standard product.
Column: TSKgel Multipore H _XL -M x 3 + guardcolumn (manufactured by Tosoh Corporation)
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min
Detector: RI detector Column temperature: 40 ° C
Injection volume: 100 μl
Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation)

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

無水酢酸２０．００部及びマロン酸５．００部を仕込み、２３℃で３０分間攪拌した。得られた混合物に硫酸０．２４部を仕込み、２３℃で３０分間攪拌した。その後、（ａ’−１）１１．２６部を添加した。得られた混合物を２３℃で３０分間攪拌し、８０℃まで昇温し、更に２時間攪拌した。２３℃まで冷却し、酢酸エチル１００部及びイオン交換水５０部を仕込み２３℃で３０分間攪拌した。その後、分液することにより有機層を回収した。この水洗の操作を７回行った。回収された有機層を濃縮し、得られた濃縮物に、メチルｔ−ブチルエーテル２０部を加えて２３℃で３時間攪拌し、ろ過することにより、固体として、モノマー（ａ−１）７．４５部を得た。
ＭＳ：３２０．１ Example 1 [Synthesis of Monomer (a-1)]

20.00 parts of acetic anhydride and 5.00 parts of malonic acid were charged and stirred at 23 ° C. for 30 minutes. The obtained mixture was charged with 0.24 part of sulfuric acid and stirred at 23 ° C. for 30 minutes. Thereafter, 11.26 parts of (a′-1) was added. The obtained mixture was stirred at 23 ° C. for 30 minutes, heated to 80 ° C., and further stirred for 2 hours. After cooling to 23 ° C., 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added and stirred at 23 ° C. for 30 minutes. Thereafter, the organic layer was recovered by liquid separation. This washing operation was performed 7 times. The recovered organic layer was concentrated, 20 parts of methyl t-butyl ether was added to the resulting concentrate, and the mixture was stirred at 23 ° C. for 3 hours and filtered to give monomer (a-1) 7.45 as a solid. Got a part.
MS: 320.1

無水酢酸２０．００部及びマロン酸５．００部を仕込み、２３℃で３０分間攪拌した。得られた混合物に硫酸０．２４部を仕込み、２３℃で３０分間攪拌した。その後、（ａ’−２）８．７６部を添加した。得られた混合物を２３℃で３０分間攪拌し、８０℃まで昇温し、更に２時間攪拌した。２３℃まで冷却し、酢酸エチル１００部及びイオン交換水５０部を仕込み２３℃で３０分間攪拌した。その後、分液することにより有機層を回収した。この水洗の操作を７回行った。回収された有機層を濃縮し、カラム（メルク製シリカゲル６０−２００メッシュ、展開溶媒：酢酸エチル）により分取して、モノマー（ａ−２）１．１２部を得た。
ＭＳ：２６８．１ Example 2 [Synthesis of Monomer (a-2)]

20.00 parts of acetic anhydride and 5.00 parts of malonic acid were charged and stirred at 23 ° C. for 30 minutes. The obtained mixture was charged with 0.24 part of sulfuric acid and stirred at 23 ° C. for 30 minutes. Thereafter, 8.76 parts of (a′-2) was added. The obtained mixture was stirred at 23 ° C. for 30 minutes, heated to 80 ° C., and further stirred for 2 hours. After cooling to 23 ° C., 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added and stirred at 23 ° C. for 30 minutes. Thereafter, the organic layer was recovered by liquid separation. This washing operation was performed 7 times. The collected organic layer was concentrated and fractionated with a column (silica gel 60-200 mesh, developing solvent: ethyl acetate) to obtain 1.12 parts of monomer (a-2).
MS: 268.1

Resin synthesis Monomers used for resin synthesis are shown below.

Example 3 [Synthesis of Resin A1]
Monomer F, monomer G, monomer (a-1) and monomer C were charged at a molar ratio of 40: 10: 10: 40, and 1.5 weight times dioxane of the total monomer amount was added to prepare a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and heated at 753 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a mixed solvent of a large amount of methanol and water three times to obtain a copolymer having a weight average molecular weight of 7.0 × 10 ^{3 in} a yield of 65%. . This copolymer has a structural unit derived from a monomer of the following formula, and this is designated as resin A1. The molar ratio of each structural unit is F ′: G ′ :( a-1) ′: C ′ = 31.7: 11.7: 10.4: 46.2.

Example 4 [Synthesis of Resin A2]
Monomer F, monomer G, monomer (a-1) and monomer B were charged at a molar ratio of 40: 10: 10: 40, and 1.5 weight times dioxane of the total monomer amount was added to prepare a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and heated at 753 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a mixed solvent of a large amount of methanol and water three times to obtain a copolymer having a weight average molecular weight of 7.0 × 10 ^{3 in} a yield of 65%. . This copolymer has a structural unit derived from a monomer of the following formula, and this is designated as resin A1. The molar ratio of each structural unit is F ′: G ′ :( a-1) ′: B ′ = 31.2: 11.9: 10.2: 46.7.

Example 5 [Synthesis of Resin A3]
Monomer F, monomer G, monomer (a-2) and monomer B were charged at a molar ratio of 40: 10: 10: 40, and 1.5 weight times dioxane of the total monomer amount was added to prepare a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and heated at 753 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a mixed solvent of a large amount of methanol and water three times to obtain a copolymer having a weight average molecular weight of 7.0 × 10 ^{3 in} a yield of 65%. . This copolymer has a structural unit derived from a monomer of the following formula, and this is designated as resin A1. The molar ratio of each structural unit is F ′: G ′ :( a-2) ′: B ′ = 31.3: 11.8: 10.8: 46.1.

[Synthesis of Resin X1]
Monomer F, monomer G, and monomer B were charged at a molar ratio of 50:25:25, and 1.5 times the total amount of dioxane was added to form a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and heated at 80 ° C. for about 8 hours. Thereafter, the reaction solution was purified by pouring it into a mixed solvent of a large amount of methanol and water three times to obtain a copolymer having a weight average molecular weight of 9.2 × 10 ^{3 in} a yield of 60%. . This copolymer has a structural unit derived from a monomer of the following formula, and this is designated as resin X1. The molar ratio of each structural unit is F ′: G ′: B ′ = 42.6: 28.7: 28.7.

  The components in Table 1 were mixed with the following solvent and dissolved, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist solution.

＜塩基性化合物：クエンチャー＞
Ｑ１：２，６−ジイソプロピルアニリン
＜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
２−ヘプタノン ２０．０部
プロピレングリコールモノメチルエーテル ２０．０部
γ−ブチロラクトン ３．５部 <Resin>
Resins A1 to A3 and Resin X1 synthesized in the resin synthesis example
<Acid generator>
Acid generator B1:

<Basic compound: Quencher>
Q1: 2,6-diisopropylaniline <solvent>
Propylene glycol monomethyl ether acetate 265 parts 2-heptanone 20.0 parts Propylene glycol monomethyl ether 20.0 parts γ-butyrolactone 3.5 parts

An organic antireflective coating composition [ARC-29; manufactured by Nissan Chemical Industries, Ltd.] was applied onto a 12-inch silicon wafer and baked at 205 ° C. for 60 seconds to obtain a thickness of 78 nm. An organic antireflection film was formed. Next, the above resist composition was spin-coated on the organic antireflection film so that the film thickness after drying was 85 nm.
The obtained silicon wafer was pre-baked (PB) for 60 seconds on the direct hot plate at the temperature described in the “PB” column of Table 1. Using the ArF excimer stepper for immersion exposure [XT: 1900 Gi; manufactured by ASML, NA = 1.35, 3/4 Annular XY polarized light] on the wafer thus obtained, the exposure amount was changed stepwise. The line and space pattern was subjected to immersion exposure while being changed.
After the exposure, post exposure bake (PEB) is performed on the hot plate at a temperature described in the “PEB” column of Table 1 for 60 seconds, and further with a 2.38 mass% tetramethylammonium hydroxide aqueous solution for 60 seconds. Paddle development was performed.

In each resist film, the exposure amount at which the 50 nm line and space pattern becomes an exposure amount of 1: 1 was defined as the effective sensitivity.
Resolution evaluation: In terms of effective sensitivity, the resist pattern is observed with a scanning electron microscope. The resolution of 45 nm is ○ (in particular, the resolution of 43 nm is ◎) and the resolution is not. X.
The results are shown in Table 2. The number in parentheses indicates the pattern width.
Line edge roughness evaluation (LER): The surface of the resist pattern after the lithography process is observed with a scanning electron microscope, and the contact width of the unevenness on the side wall of the resist pattern is 5 nm or less. did.
The results are shown in Table 2. The numerical value in the parenthesis indicates the touch width of the unevenness on the side wall.

  According to the compound of the present invention, a pattern having excellent resolution and line edge roughness (LER) can be formed using a resist composition containing a resin obtained by polymerizing the compound.

Claims (8)

A compound represented by formula (I).

[In the formula (I),
W represents a saturated hydrocarbon ring having 3 to 36 carbon atoms, and —CH ₂ — contained in the saturated hydrocarbon ring may be replaced by —O—, —SO ₂ — or —CO—.
A ¹ represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and —CH ₂ — contained in the divalent saturated hydrocarbon group is replaced by —O— or —CO—. May be.
R ¹ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. ] The compound of Claim 1 represented by a formula (II).

[In Formula (II), A ¹ and R ¹ represent the same meaning as described above. ] The compound according to claim ¹ , wherein A ¹ is represented by a single bond or * —CH ₂ —CO—O— (* represents a bond to —O—).   Resin which has a structural unit derived from the compound in any one of Claims 1-3.   The resin according to claim 4, which has an acid labile group, is insoluble or hardly soluble in an aqueous alkali solution, and can be dissolved in an aqueous alkali solution by the action of an acid.   A resist composition comprising the resin according to claim 4 or 5 and an acid generator.   Furthermore, the resist composition of Claim 6 containing a basic compound. (1) The process of apply | coating the resist composition of Claim 6 or 7 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 using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) A method for producing a resist pattern, comprising a step of developing the heated composition layer using a developing device.