JP2012078815A - Resist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist composition with which a pattern having an excellent mask error enhancement factor (MEEF) can be obtained.SOLUTION: A resist composition contains a polymer (1) or a polymer (2) (these contain a monomer-derived structural unit of the formula (I)); a resin having a group unstable to acid, being insoluble or poorly-soluble in an aqueous alkali solution and being capable of dissolving in an aqueous alkali solution by action of acid; and an acid generator. [In the formula, Rrepresents a hydrogen atom or a methyl group; Rand Reach independently represents a hydrocarbon group or are bonded to each other to form a ring, where the group may be substituted by a halogen atom, a nitro group, a hydroxyl group or a cyano group, -CH- included in the group may be replaced with -O-, -CO-, -SO- or -NH-, and =CH- included in the hydrocarbon group may be replaced with =N-; Arepresents a single bond or a divalent linking group.]

Description

  The present invention relates to a resist composition.

In Patent Document 1, 2-ethyladamantan-2-yl methacrylate, 3-hydroxyadamantan-1-yl methacrylate, methacrylic acid = 2- (5-oxo-4-oxatricyclo [4.2.1. 03,7] nonan-2-yloxy) -2-oxoethyl and α-methacryloyloxy-γ-butyrolactone, a resin comprising structural units, and triphenylsulfonium 1-((3-hydroxyadamantyl) methoxycarbonyl) A resist composition containing an acid generator composed of difluoromethanesulfonate, a quencher composed of 2,6-diisopropylaniline, and a solvent is described.
Patent Document 2 includes 2-isopropyladamantan-2-yl methacrylate, 1-ethylcyclohexane-1-yl methacrylate, 3-hydroxyadamantan-1-yl methacrylate, 5-methacryloyloxy-2,6-norbornanecarbox. A resin comprising a structural unit derived from a lactone, α-methacryloyloxy-γ-butyrolactone, and 2,2,2-trifluoroacetophenone = O-[[2- (methacryloyloxy) ethane-1-yl] oxycarbonyldifluoro Methanesulfonyl] oxime and a polymer comprising a structural unit derived from 1-ethylcyclohexane-1-yl methacrylate and an acid generator comprising triphenylsulfonium 1-((3-hydroxyadamantyl) methoxycarbonyl) difluoromethanesulfonate And 2,6 A quencher made of diisopropylaniline, the resist composition containing a solvent is described.

JP 2008-170983 A US Patent Application Publication No. 2010/0021847

  Conventional resist compositions may not always satisfy the mask error enhancement factor (MEEF) of the resulting pattern.

［式（Ｉ）中、Ｒ^１は、水素原子又はメチル基を表す。
Ｒ^２及びＲ^３は、それぞれ独立に、炭素数１〜２０の炭化水素基を表し、Ｒ^２及びＲ^３は互いに結合して環を形成してもよく、該炭化水素基に含まれる水素原子は、ハロゲン原子、ニトロ基、ヒドロキシ基又はシアノ基で置換されていてもよく、該炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＣＯ−、−ＳＯ_２−又は−ＮＨ−で置き換わっていてもよく、該炭化水素基に含まれる＝ＣＨ−は、＝Ｎ−で置き換わっていてもよい。
Ａ¹は、単結合又は２価の連結基を表す。］

［式（ＩＩ）中、Ｒ^４は、水素原子又はメチル基を表す。
Ｒ^５は、置換基を有してもよい炭素数１〜３０の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＣＯ−、−ＳＯ_２−又は−ＮＨ−で置き換わってもよい。］

［式（ＩＩＩ）中、Ｒ^６は、水素原子又はメチル基を表す。
Ｒ^７及びＲ^８は、それぞれ独立に、炭素数１〜２０の炭化水素基を表し、Ｒ^７及びＲ^８は互いに結合して環を形成してもよく、該炭化水素基に含まれる水素原子は、ハロゲン原子、ニトロ基、ヒドロキシ基又はシアノ基で置換されていてもよく、該炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＣＯ−、−ＳＯ_２−又は−ＮＨ−で置き換わっていてもよく、該炭化水素基に含まれる＝ＣＨ−は、＝Ｎ−で置き換わっていてもよい。
Ａ^２は、単結合又は−（ＣＨ_２）_ｍ’−ＣＯ−Ｏ−^＊を表す。
ｍ’は、１〜６の整数を表す。
＊は、Ｎとの結合手を表す。］ The present invention includes the following inventions.
[1] One or more polymers selected from the group consisting of the polymer (1) and the polymer (2), an acid-labile group, and insoluble or hardly soluble in an alkaline aqueous solution, A resist composition comprising a resin that can be dissolved in an alkaline aqueous solution by an action and an acid generator.
Polymer (1): A polymer comprising structural units derived from the monomer represented by formula (I).
Polymer (2): a structural unit derived from the monomer represented by formula (I), a structural unit derived from the monomer represented by formula (II), and a structure derived from the monomer represented by formula (III) A polymer comprising one or more structural units selected from the group consisting of units.

[In Formula (I), R ¹ represents a hydrogen atom or a methyl group.
R ² and R ³ each independently represent a hydrocarbon group having 1 to 20 carbon atoms, R ² and R ³ may be bonded to each other to form a ring, and a hydrogen atom contained in the hydrocarbon group May be substituted with a halogen atom, a nitro group, a hydroxy group or a cyano group, and —CH ₂ — contained in the hydrocarbon group is —O—, —CO—, —SO ₂ — or —NH—. ═CH— contained in the hydrocarbon group may be replaced with ═N—.
A ¹ represents a single bond or a divalent linking group. ]

[In the formula (II), R ⁴ represents a hydrogen atom or a methyl group.
R ⁵ represents a C 1-30 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —O—, —CO—, —SO _2. -Or -NH- may be substituted. ]

[In the formula (III), R ⁶ represents a hydrogen atom or a methyl group.
R ⁷ and R ⁸ each independently represent a hydrocarbon group having 1 to 20 carbon atoms, and R ⁷ and R ⁸ may be bonded to each other to form a ring, and a hydrogen atom contained in the hydrocarbon group May be substituted with a halogen atom, a nitro group, a hydroxy group or a cyano group, and —CH ₂ — contained in the hydrocarbon group is —O—, —CO—, —SO ₂ — or —NH—. ═CH— contained in the hydrocarbon group may be replaced with ═N—.
A ² represents a single bond or — (CH ₂ ) _{m ′} —CO—O— ^* .
m ′ represents an integer of 1 to 6.
* Represents a bond with N. ]

  According to the resist composition of the present invention, a pattern having an excellent mask error enhancement factor (MEEF) can be obtained.

In this specification, unless otherwise specified, specific chemical substituents described later can be applied to any chemical structural formula having the same substituents while appropriately selecting the number of carbon atoms. Those which can take any of linear, branched or cyclic include any of them unless otherwise specified, and in the same group, linear, branched and cyclic partial structures are mixed. Also good. Furthermore, each substituent can be a monovalent or divalent substituent depending on the binding site. When stereoisomers exist, all of those stereoisomers are included.
The term "(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 has at least one polymer selected from the group consisting of the polymer (1) and the polymer (2), an acid-labile group, and is insoluble or hardly soluble in an alkaline aqueous solution. A resin (hereinafter sometimes referred to as “resin (A)”) that can be dissolved in an alkaline aqueous solution by the action of an acid, and an acid generator (hereinafter sometimes referred to as “acid generator (B)”). .
Furthermore, it is preferable that a solvent, a basic compound, etc. are included.

［式（Ｉ）中、Ｒ^１は、水素原子又はメチル基を表す。
Ｒ^２及びＲ^３は、それぞれ独立に、炭素数１〜２０の炭化水素基を表し、Ｒ^２及びＲ^３は互いに結合して環を形成してもよく、該炭化水素基に含まれる水素原子は、ハロゲン原子、ニトロ基、ヒドロキシ基又はシアノ基で置換されていてもよく、該炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＣＯ−、−ＳＯ_２−又は−ＮＨ−で置き換わっていてもよく、該炭化水素基に含まれる＝ＣＨ−は、＝Ｎ−で置き換わっていてもよい。
Ａ¹は、単結合又は２価の連結基を表す。］ <Polymer (1)>
The polymer (1) is a polymer composed of structural units derived from the monomer represented by the formula (I).
<Monomer represented by formula (I)>

[In Formula (I), R ¹ represents a hydrogen atom or a methyl group.
R ² and R ³ each independently represent a hydrocarbon group having 1 to 20 carbon atoms, R ² and R ³ may be bonded to each other to form a ring, and a hydrogen atom contained in the hydrocarbon group May be substituted with a halogen atom, a nitro group, a hydroxy group or a cyano group, and —CH ₂ — contained in the hydrocarbon group is —O—, —CO—, —SO ₂ — or —NH—. ═CH— contained in the hydrocarbon group may be replaced with ═N—.
A ¹ represents a single bond or a divalent linking group. ]

Examples of the hydrocarbon group include an alkyl group, a saturated cyclic hydrocarbon group, an aromatic hydrocarbon group, and combinations thereof.
Examples of the alkyl group include linear and branched alkyl groups.
Examples of the linear alkyl group, a methyl group ^(R 2 -1), ethyl ^(R 2 -2), n- propyl group ^(R 2 -3), n- butyl group ^(R 2 -4), n - pentyl ^(R 2 -5), n-hexyl group ^(R 2 -6), n-heptyl group ^(R 2 -7), n-octyl group ^(R 2 -8), n-nonyl group ^{(R 2} -9), decyl ^(R 2 -10), undecyl ^(R 2 -11), dodecyl ^(R 2 -12), and the like.
The branched alkyl group, an isopropyl group ^(R 2 -13), sec- butyl ^(R 2 -14), tert- butyl ^(R 2 -15), and the like following groups. Preferably ^{(R 2 -13), (R} 2 -14), include (R 2 -15).

Examples of the saturated cyclic hydrocarbon group include the following groups.

Examples of the aromatic hydrocarbon group include a phenyl group (R ² -51), a biphenyl group (R ² -52), a fluorenyl group (R ² -53), a naphthyl group (R ² -54), and an anthryl group (R ² -55), p- methylphenyl group, p-tert-butylphenyl group, p- adamantyl phenyl group, a tolyl group, a xylyl group, cumenyl group, mesityl group, a biphenyl group, phenanthryl group, 2,6-diethyl-phenyl And aryl groups such as 2-methyl-6-ethylphenyl.

Examples of the substituent in the hydrocarbon group include a halogen atom, a cyano group, a nitro group, and a hydroxy group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of R ² and R ³ include the following groups.

In R ² and R ³ , a group in which —CH ₂ — contained in a hydrocarbon group is replaced by —O—, —CO—, —SO ₂ — or —NH— and ═CH— contained in the hydrocarbon group Examples of the group replaced by ═N— include the following groups.

Examples of the ring formed by combining R ² and R ³ with each other include saturated cyclic hydrocarbons. Examples of the ═C (R ² ) (R ³ ) group when bonded to each other to form a ring include the following groups.

Examples of the divalent linking group include groups in which any hydrogen atom of the above-described hydrocarbon group is replaced with a bond. Further, the divalent linking group may contain a hetero atom, and preferred examples include a group in which —CH ₂ — contained in a divalent hydrocarbon group is replaced by —O— or —CO—.
Examples of A ¹ include the following groups.

Examples of the group in which —CH ₂ — in A ¹ is replaced by —O— or —CO— include the following groups.

  Specific examples of the monomer represented by the formula (I) are shown in the table.

<Method for producing polymer (1)>
The polymer (1) can be produced by polymerizing the monomer represented by the formula (I).
For example, in an inert solvent, an initiator is added to the monomer represented by the formula (I) and reacted to obtain a mixture containing the polymer (1). This mixture is added to the solvent, and the precipitated solid Can be obtained by taking out.
Examples of the inert solvent include dioxane, tetrahydrofuran, acetonitrile, dichloroethane and the like.
Examples of the solvent to which the mixture is added include polar solvents such as water and methanol, and nonpolar solutions such as hexane and heptane.
Examples of the polymerization initiator include azobisisobutyronitrile, azobis (2,4-dimethylvaleronitrile), benzoyl peroxide, and the like. The reaction temperature is usually room temperature to 100 ° C, preferably 60 to 80 ° C.

［式（ＩＩ）中、Ｒ^４は、水素原子又はメチル基を表す。
Ｒ^５は、置換基を有してもよい炭素数１〜３０の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＣＯ−、−ＳＯ_２−又は−ＮＨ−で置き換わってもよい。］ <Polymer (2)>
The polymer (2) is derived from the structural unit derived from the monomer represented by the formula (I), the structural unit derived from the monomer represented by the formula (II), and the monomer represented by the formula (III). A polymer comprising one or more structural units selected from the group consisting of structural units.
<Monomer represented by formula (II)>

[In the formula (II), R ⁴ represents a hydrogen atom or a methyl group.
R ⁵ represents a C 1-30 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —O—, —CO—, —SO _2. -Or -NH- may be substituted. ]

Examples of the saturated hydrocarbon group include an alkyl group, a saturated cyclic hydrocarbon group, and combinations thereof.
Examples of the substituent in the saturated hydrocarbon group include a halogen atom, a cyano group, a nitro group, a hydroxy group, a carboxy group, and an acyl group having 2 to 11 carbon atoms.
Examples of the acyl group include an acetyl group, a propanoyl group, a butyryl group, an isobutyryl group, a pivaloyl group, a cyclohexanecarbonyl group, an adamantanecarbonyl group, and a benzoyl group.

  Examples of the monomer represented by the formula (II) include a monomer represented by the following formula (IV), a monomer represented by the formula (V), a monomer represented by the formula (VI), and the formula (VII). A monomer represented by formula (a1-1), a monomer represented by formula (a1-2), a monomer represented by formula (a3-1), a formula (a3-2) ), A monomer represented by the formula (a3-3), and the like.

［式（ＩＶ）中、環Ｗ^１は、炭素数３〜２４の飽和炭化水素環を表す。
Ａ^３は、単結合又は^＊−（ＣＨ₂)_s1−ＣＯ−Ｏ−を表し、＊は−Ｏ−との結合手を表し、ｓ１は１〜６の整数を表す。
Ｒ^９は、水素原子又はメチル基を表す。
Ｒ^１０及びＲ^１１は、それぞれ独立に、炭素数１〜６のアルキル基又は炭素数１〜６のハロゲン化アルキル基を表す。
ただし、Ａ^３、環Ｗ^１、Ｒ^１０及びＲ^１１の炭素数の合計は、３０以下である。］ <Monomer represented by formula (IV)>

[In Formula (IV), Ring W ¹ represents a saturated hydrocarbon ring having 3 to 24 carbon atoms.
A ³ represents a single bond or ^* — (CH ₂ ) _s1 —CO—O—, * represents a bond with —O—, and s1 represents an integer of 1 to 6.
R ⁹ represents a hydrogen atom or a methyl group.
R ¹⁰ and R ¹¹ each independently represent an alkyl group having 1 to 6 carbon atoms or a halogenated alkyl group having 1 to 6 carbon atoms.
However, the total number of carbon atoms of A ³ , ring W ¹ , R ¹⁰ and R ¹¹ is 30 or less. ]

The saturated hydrocarbon ring may be monocyclic or polycyclic. Examples of the monocyclic saturated hydrocarbon ring include cycloalkane rings such as a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, and a cyclooctane ring. Examples of the polycyclic saturated hydrocarbon ring include decahydronaphthalene ring, adamantane ring, norbornane ring, and the following rings.

  Examples of the halogenated alkyl group include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluorosec-butyl group, perfluorotert-butyl group, perfluoropentyl group, perfluorohexyl group, trichloromethyl. Group, tribromomethyl group, triiodomethyl group and the like.

Ａ^３としては、単結合又は^＊−ＣＨ_２−ＣＯ−Ｏ−（＊は−Ｏ−との結合手を表す。）であることがより好ましい。
Ｒ^９は、水素原子又はメチル基であることが好ましい。
Ｒ¹⁰及びＲ¹¹は、それぞれ独立に、炭素数１〜６のハロゲン化アルキル基であることが好ましく、炭素数１〜６のパーフルオロアルキル基であることがより好ましく、トリフルオロメチル基、パーフルオロエチル基又はパーフルオロプロピル基であることが特に好ましい。 In Formula (IV), W ¹ is preferably a ring represented by Formula (a1-1) to Formula (a1-3).

A ³ is more preferably a single bond or ^* —CH ₂ —CO—O— (* represents a bond to —O—).
R ⁹ is preferably a hydrogen atom or a methyl group.
R ¹⁰ and R ¹¹ are each independently preferably a halogenated alkyl group having 1 to 6 carbon atoms, more preferably a perfluoroalkyl group having 1 to 6 carbon atoms, a trifluoromethyl group, A fluoroethyl group or a perfluoropropyl group is particularly preferable.

Examples of the monomer represented by the formula (IV) include the following monomers.

（式中、Ｒ^９、Ｒ^１０、Ｒ^１１及びＡ^３は、上記と同じ意味を表す。） Especially, as a monomer represented by Formula (IV), the following monomers are preferable.

(In formula, R < ⁹ >, R < ¹⁰ >, R < ¹¹ > and A < ³ > represent the same meaning as the above.)

More specifically, examples of the monomer represented by the formula (IV) include compounds represented by the following.

［式（ＩＶ−ａ）及び式（ＩＶ−ｂ）中、Ｗ^１、Ａ^３、Ｒ^９、Ｒ^１０及びＲ^１１は、上記と同じ意味を表す。］ The monomer represented by the formula (IV) can be produced, for example, by reacting the compound represented by the formula (IV-a) with the compound represented by the formula (IV-b).
Examples of the compound represented by the formula (IV-a) include 1-methacryloyloxy-4-oxoadamantane described in JP-A-2002-226436. Examples of the compound represented by the formula (IV-b) include pentafluoropropionic anhydride, heptafluorobutyric anhydride, and trifluoroacetic anhydride.
The reaction is preferably performed at the boiling temperature of the compound represented by the formula (IV-b).

[In Formula (IV-a) and Formula (IV-b), W ¹ , A ³ , R ⁹ , R ¹⁰ and R ¹¹ represent the same meaning as described above. ]

［式（Ｖ）中、Ｒ^１２は、炭素数１〜６のフッ化アルキル基を表す。
Ｒ^１３は、水素原子又はメチル基を表す。
Ａ^４は、炭素数１〜１０の２価の飽和炭化水素基を表す。］ <Monomer represented by formula (V)>

Wherein ^{(V), R 12} represents a fluoroalkyl group having 1 to 6 carbon atoms.
R ¹³ represents a hydrogen atom or a methyl group.
A ⁴ represents a divalent saturated hydrocarbon group having 1 to 10 carbon atoms. ]

Examples of the fluorinated alkyl group include difluoromethyl group, trifluoromethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, perfluoroethyl group, 1, 1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1- (trifluoromethyl) -1,2,2,2-tetra Fluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group, 1,1,2,2,3,3 4,4-octafluorobutyl group, perfluorobutyl group, 1,1-bis (trifluoro) methyl-2,2,2-trifluoroethyl group, 2- (perfluoropropyl) ethyl group, , 1,2,2,3,3,4,4-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, perfluoropentylmethyl group, perfluorohexyl Groups.
Examples of the divalent saturated hydrocarbon group include the following groups.

In the formula (V), R ¹² is preferably a fluorinated alkyl group having 1 to 4 carbon atoms, more preferably a trifluoromethyl group, a perfluoroethyl group or a perfluoropropyl group, still more preferably a trifluoride group. A fluoromethyl group;

Examples of the monomer represented by the formula (V) include the following monomers.

［式（ＶＩ）中、Ｒ^１４は、炭素数１〜６のフッ化アルキル基を表す。
Ｒ^１５は、水素原子又は炭素数１〜６のフッ化アルキル基を表す。
Ｒ^１６は、水素原子又は炭素数２〜５のアシル基を表す。
Ｒ^１７は、水素原子又はメチル基を表す。
Ｂ^１は、炭素数１〜１０の２価の飽和炭化水素基を表す。 <Monomer represented by formula (VI)>

[In the formula (VI), R ¹⁴ represents a fluorinated alkyl group having 1 to 6 carbon atoms.
R ¹⁵ represents a hydrogen atom or a fluorinated alkyl group having 1 to 6 carbon atoms.
R ¹⁶ represents a hydrogen atom or an acyl group having 2 to 5 carbon atoms.
R ¹⁷ represents a hydrogen atom or a methyl group.
B ¹ represents a divalent saturated hydrocarbon group having 1 to 10 carbon atoms.

Examples of the monomer represented by the formula (VI) include the following compounds.

［式（ＶＩＩ）中、環Ｗ^１’は、炭素数３〜２４の飽和炭化水素環を表す。
Ａ^３’は、単結合又は^＊−（ＣＨ₂）_S'1−ＣＯ−Ｏ−を表し、＊は−Ｏ−との結合手を表し、Ｓ’１は１〜６の整数を表す。
Ｒ^９’は、水素原子又はメチル基を表す。
Ｒ^１０’は、炭素数１〜６のアルキル基又は炭素数１〜６のハロゲン化アルキル基を表す。
ただし、Ａ^３’、環Ｗ^１’及びＲ^１０’の炭素数の合計は、３０以下である。］
式（ＶＩＩ）で表されるモノマーとして、より具体的には、以下で表される化合物、国際特許公報２００８／０１５８７６に記載のモノマー等が挙げられる。 <Monomer represented by formula (VII)>

[In Formula (VII), Ring W ^{1 ′} represents a saturated hydrocarbon ring having 3 to 24 carbon atoms.
A ^{3 ′} represents a single bond or ^* — (CH ₂ ) _S′1 —CO—O—, * represents a bond with —O—, and S′1 represents an integer of 1 to 6.
R ^{9 ′} represents a hydrogen atom or a methyl group.
R ^{10 ′} represents an alkyl group having 1 to 6 carbon atoms or a halogenated alkyl group having 1 to 6 carbon atoms.
However, the total number of carbon atoms of A ^{3 ′} , ring W ^{1 ′} and R ^{10 ′} is 30 or less. ]
More specifically, examples of the monomer represented by the formula (VII) include a compound represented by the following, a monomer described in International Patent Publication No. 2008/015876, and the like.

［式（ＩＩＩ）中、Ｒ^６は、水素原子又はメチル基を表す。
Ｒ^７及びＲ^８は、それぞれ独立に、炭素数１〜２０の炭化水素基を表し、Ｒ^７及びＲ^８は互いに結合して環を形成してもよく、該炭化水素基に含まれる水素原子は、ハロゲン原子、ニトロ基、ヒドロキシ基又はシアノ基で置換されていてもよく、該炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＣＯ−、−ＳＯ_２−又は−ＮＨ−で置き換わっていてもよく、該炭化水素基に含まれる＝ＣＨ−は、＝Ｎ−で置き換わっていてもよい。
Ａ^２は、単結合又は−（ＣＨ_２）_ｍ’−ＣＯ−Ｏ−^＊を表す。
ｍ’は、１〜６の整数を表す。
＊は、Ｎとの結合手を表す。］ <Monomer represented by formula (III)>

[In the formula (III), R ⁶ represents a hydrogen atom or a methyl group.
R ⁷ and R ⁸ each independently represent a hydrocarbon group having 1 to 20 carbon atoms, and R ⁷ and R ⁸ may be bonded to each other to form a ring, and a hydrogen atom contained in the hydrocarbon group May be substituted with a halogen atom, a nitro group, a hydroxy group or a cyano group, and —CH ₂ — contained in the hydrocarbon group is —O—, —CO—, —SO ₂ — or —NH—. ═CH— contained in the hydrocarbon group may be replaced with ═N—.
A ² represents a single bond or — (CH ₂ ) _{m ′} —CO—O— ^* .
m ′ represents an integer of 1 to 6.
* Represents a bond with N. ]

Examples of R ⁷ and R ⁸ include the same as R ² and R ³ .
A ² includes the following groups. The group represented by the formula (A ² -1) represents a single bond.

  Specific examples of the monomer represented by the formula (III) are shown in the table.

Examples of the polymer (2) include the following polymers.

<Method for producing polymer (2)>
The polymer (2) polymerizes the monomer represented by the formula (I) and one or more monomers selected from the group consisting of the monomer represented by the formula (II) and the monomer represented by the formula (III). Can be manufactured.
For example, in an inert solvent, an initiator is added to the monomer represented by the formula (I) and reacted to obtain a mixture containing the polymer (2), and the mixture is added to the solvent and precipitated. It can be obtained by removing the solid.
The solvent, agent, conditions, and the like used can be the same as those for the polymer (1).

The content of the structural unit derived from the monomer represented by the formula (I) in the polymer (2) is usually 99 to 1 mol with respect to 100 mol of all units of the polymer (2), preferably It is 99-5 mol, More preferably, it is 99-10 mol.
The content of the structural unit derived from the monomer represented by the formula (II) in the polymer (2) is usually 1 to 99 mol with respect to 100 mol of all units of the polymer (2), preferably It is 1-95 mol, More preferably, it is 1-90 mol.
The content of the structural unit derived from the monomer represented by the formula (III) in the polymer (2) is usually 1 to 99 mol with respect to 100 mol of all units of the polymer (2), preferably It is 1-95 mol, More preferably, it is 1-90 mol.

  In addition, any one of the polymer (1) and the polymer (2) may be used. In this case, each polymer may be a combination of two or more different polymers. Moreover, you may use both a polymer (1) and a polymer (2) together. The ratio in the case of using together, Preferably the ratio of a polymer (2) is 20-80 mass parts with respect to 100 mass parts of polymers (1), More preferably, it is 40-60 mass parts.

<Resin (A)>
The resin (A) is insoluble or hardly soluble in an alkaline aqueous solution before contact with an acid, and has a property of being soluble in an alkaline aqueous solution by the action of an acid. That is, in the resin (A), a part or all of the hydrophilic group in the molecule is protected by a protecting group that can be removed by contact with an acid, and when this comes in contact with an acid, the protecting group is removed, It becomes a resin soluble in an alkaline aqueous solution.
In the present specification, a hydrophilic group protected by such a protecting group is referred to as an “acid labile group”. Examples of such a hydrophilic group include a carboxy group or a hydroxy group, and a carboxy group is more preferable.

  The resin (A) can be produced by polymerizing a monomer having an acid labile group (hereinafter referred to as “monomer (a1)”). Monomers (a1) may be used alone or in combination of two or more.

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し、Ｒ^a1及びＲ^a2は互いに結合して、それらが結合する炭素原子とともに炭素数３〜２０の環を形成してもよく、該アルキル基、該脂環式炭化水素基及び該環に含まれる−ＣＨ_２−は、−Ｏ−、−Ｓ−又は−ＣＯ−で置き換わっていてもよい。＊は結合手を表す。 <Monomer (a1) having acid labile group>
The monomer (a1) has an acid labile group.
The acid labile group in the case where the hydrophilic group is a carboxy group is, for example, one represented by the following formula (1) (hereinafter sometimes referred to as “acid labile group (1)”).

In the formula (1), R ^a1 , R ^a2 and R ^a3 each independently represents an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms, and R ^a1 and R ^a2 are They may be bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded, and the alkyl group, the alicyclic hydrocarbon group, and —CH ₂ — contained in the ring are — O-, -S- or -CO- may be substituted. * Represents a bond.

Ｒ^a1〜Ｒ^a3の脂環式炭化水素基は、飽和炭化水素基であることが好ましく、その炭素数は１〜１６であるものがより好ましい。 The alicyclic hydrocarbon group may be monocyclic or polycyclic, saturated or unsaturated. The alicyclic hydrocarbon group of monocyclic, a cycloalkyl group shown in the above ^{(R 2 -31) ~ (R} 2 -37). Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, a methylnorbornyl group, and the groups shown below.

The alicyclic hydrocarbon group of R ^{a1 to} R ^a3 is preferably a saturated hydrocarbon group, and more preferably one having 1 to 16 carbon atoms.

このような環の炭素数は、好ましくは３〜１２である。 When R ^a1 and R ^a2 are bonded to each other to form a ring, examples of the group represented by —C (R ^a1 ) (R ^a2 ) (R ^a3 ) include the following groups.

The number of carbon atoms in such a ring is preferably 3-12.

Specific examples of the acid labile group (1) are:
1,1-dialkylalkoxycarbonyl group (in formula (1), R ^{a1 to} R ^a3 are all alkyl groups, and one of these alkyl groups is preferably a tert-butoxycarbonyl group),
2-alkyladamantan-2-yloxycarbonyl group (in the formula (1), R ^a1 and R ^a2 are bonded to each other to form an adamantyl ring together with the carbon atoms to which they are bonded, and R ^a3 is an alkyl group) And 1- (adamantan-1-yl) -1-alkylalkoxycarbonyl group (in the formula (1), R ^a1 and R ^a2 are alkyl groups, and R ^a3 is an adamantyl group).

  The monomer (a1) is preferably a monomer having an acid labile group (1) and a carbon-carbon double bond, more preferably a (meth) acrylic monomer having an acid labile group (1). Preferably, it is a (meth) acrylic monomer having an acid labile group (1).

  Among the (meth) acrylic monomers having the acid labile group (1), those having an acid labile group (1) having a partial structure of an alicyclic hydrocarbon group having 5 to 20 carbon atoms are preferable. The resin (A) obtained by polymerizing the monomer (a1) having such a sterically bulky alicyclic hydrocarbon group is obtained when a resist pattern is produced using a resist composition containing the resin (A). The resist pattern can be manufactured with better resolution.

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−で表される基を表す。ここで、ｋ１は１〜７の整数を表し、＊は−ＣＯ−との結合手である。
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のアルキル基又は炭素数３〜１０の脂環式炭化水素基を表す。
ｍ１は０〜１４の整数を表す。
ｎ１は０〜１０の整数を表す。
ｎ１’は０〜３の整数を表す。 Among (meth) acrylic monomers having an acid labile group (1) having an alicyclic hydrocarbon group as a partial structure, a monomer represented by the formula (a1-1) (hereinafter referred to as “monomer (a1-1)” Or a monomer represented by formula (a1-2) (hereinafter referred to as “monomer (a1-2)”). When manufacturing resin (A), these may be used independently and may use 2 or more types together.

In formula (a1-1) and formula (a1-2),
L ^a1 and L ^a2 each independently represent a group represented by —O— or ^* —O— (CH ₂ ) _k1 —CO—O—. Here, k1 represents an integer of 1 to 7, and * is a bond with —CO—.
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 or an alicyclic hydrocarbon group having 3 to 10 carbon atoms.
m1 represents the integer of 0-14.
n1 represents an integer of 0 to 10.
n1 ′ represents an integer of 0 to 3.

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- ( where, f1 is 1 4 represents an integer of 4, and more preferably -O-. f1 is more preferably 1.
R ^a4 and R ^a5 are preferably methyl groups.
Specifically, the alkyl group of R ^a6 and R ^a7 is preferably a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, or the like. The alkyl group for R ^a6 or R ^a7 is more preferably a group having 6 or less carbon atoms. The alicyclic hydrocarbon group for R ^a6 or R ^a7 preferably has 8 or less carbon atoms, more preferably 6 or less.
The alicyclic hydrocarbon group for R ^a6 or R ^a7 is preferably a saturated cyclic hydrocarbon group.
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, more preferably 1.

As a monomer (a1-1), the following are mentioned, for example.

  Among these, as the monomer (a1-1), 2-methyladamantan-2-yl (meth) acrylate, 2-ethyladamantan-2-yl (meth) acrylate and 2-isopropyladamantan-2-yl (meth) Acrylates are preferred, with 2-methyladamantan-2-yl methacrylate, 2-ethyladamantan-2-yl methacrylate and 2-isopropyladamantan-2-yl methacrylate being more preferred.

As a monomer (a1-2), the following are mentioned, for example.

これらの中でも、モノマー（ａ１−２）としては、１−エチルシクロヘキシル（メタ）アクリレートが好ましく、１−エチルシクロヘキシルメタクリレートがより好ましい。

Among these, as the monomer (a1-2), 1-ethylcyclohexyl (meth) acrylate is preferable, and 1-ethylcyclohexyl methacrylate is more preferable.

When the resin (A) is produced using the monomer (a1-1) and / or the monomer (a1-2), the structure derived from these monomers with respect to 100 mol of the total structural unit of the resin (A) obtained. The total content of units is preferably in the range of 10 to 95 mol, more preferably in the range of 15 to 90 mol, and still more preferably in the range of 20 to 85 mol. In order to bring the total content of the structural unit derived from the monomer (a1-1) and / or the structural unit derived from the monomer (a1-2) into such a range, when producing the resin (A) In addition, the usage amount of the monomer (a1-1) and / or the monomer (a1-2) may be adjusted with respect to the usage amount of all monomers.
When the monomer having an adamantyl group (particularly, the monomer (a1-1)) is used for the monomer (a1), the usage amount of the monomer having an adamantyl group is 15 with respect to 100 mol of the total usage amount of the monomer (a1). It is preferable to set it as mol or more.
Thereby, there exists a tendency for the dry etching tolerance of the resist pattern obtained from the resist composition containing resin (A) to become more favorable.

<Acid stable monomer>
In the resist composition of the present invention, as long as the resin (A) is a resin having an acid labile group and insoluble or hardly soluble in an aqueous alkali solution and capable of dissolving in an aqueous alkali solution by acting with an acid, It may be a copolymer having a structural unit derived from a monomer having no labile group (hereinafter sometimes referred to as “acid-stable monomer”).

  For example, when the resin (A) is produced by using an acid-stable monomer, the ratio between the amount of the monomer (a1) used and the amount of the acid-stable monomer used is [monomer (a1)] / [acid-stable monomer]. It represents, Preferably it is 10-80 mol / 90-20 mol, More preferably, it is 20-60 mol / 80-40 mol.

As an acid stable monomer, the monomer which has a hydroxyl group or a lactone ring in a molecule | numerator is mentioned.
A structural unit derived from an acid-stable monomer having a hydroxy group (hereinafter referred to as “acid-stable monomer (a2)”) and / or an acid-stable monomer having a lactone ring (hereinafter referred to as “acid-stable monomer (a3)”) When the resist composition containing the resin (A) is applied to the substrate, the resin (A) has excellent adhesion between the coating film formed on the substrate or the composition layer obtained from the coating film and the substrate. This resist composition can produce a resist pattern with good resolution.

<Acid-stable monomer having a hydroxy group (a2)>
When the acid-stable monomer (a2) is used for the production of the resin (A), a suitable acid-stable monomer (a2) is used depending on the type of exposure source when obtaining a resist pattern from the resist composition containing the resin (A). It is preferable to select.
For example, when the resist composition is used for KrF excimer laser exposure (wavelength: 248 nm), exposure to high energy rays such as an electron beam or EUV light, the acid stable monomer having a phenolic hydroxy group is used as the acid stable monomer (a2). It is preferable to use a monomer.
When used for short wavelength ArF excimer laser exposure (wavelength: 193 nm), it is preferable to use an acid stable monomer (a2-1) having adamantanol as the acid stable monomer (a2). The acid stable monomer (a2) may be used alone or in combination of two or more depending on the type of exposure source.

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 acid stable monomer (a2-1) include monomers represented by the following 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. * Represents a bond with -CO-.
R ^a14 represents a hydrogen atom or a methyl group.
R ^a15 and R ^a16 each independently represent a hydrogen atom, a methyl group or a hydroxy group.
o1 represents an integer of 0 to 10.

In formula (a2-1), L ^a3 is preferably ^* —O—, ^* —O— (CH ₂ ) _f1 —CO—O— (where f1 is an integer of 1 to 4). More preferably, it 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.

Examples of the acid stable monomer (a2-1) include the following. Among these, 3-hydroxyadamantan-1-yl (meth) acrylate, 3,5-dihydroxyadamantan-1-yl (meth) acrylate and (meth) acrylic acid 1- (3,5-dihydroxyadamantan-1-yl Oxycarbonyl) methyl is preferred, 3-hydroxyadamantan-1-yl (meth) acrylate and 3,5-dihydroxyadamantan-1-yl (meth) acrylate are more preferred, 3-hydroxyadamantan-1-yl methacrylate and 3, More preferred is 5-dihydroxyadamantan-1-yl methacrylate.

  When the resin (A) has a structural unit derived from the acid-stable monomer (a2-1), the content thereof is preferably in the range of 3 to 40 mol with respect to 100 mol of all structural units of the resin (A). The range of 5 to 35 mol is more preferable, and the range of 5 to 30 mol is more preferable.

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

式（ａ３−１）、式（ａ３−２）及び式（ａ３−３）中、
Ｌ^a4、Ｌ^a5及び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。＊は−ＣＯ−との結合手を表す。
Ｒ^a18、Ｒ^a19及び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のアルキル基を表す。
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のアルキル基を表す。
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、複数のＲ^a21、Ｒ^a22又はＲ^a23は、それぞれ独立である。 The acid stable monomer (a3) is preferably one represented by the following formula (a3-1), formula (a3-2) or formula (a3-3). In manufacture of resin (A), only 1 type may be used among these and 2 or more types may be used together. In the following description, the acid stable monomer (a3) represented by the formula (a3-1) is referred to as “acid stable monomer (a3-1)”, and the acid stable monomer (a3) represented by the formula (a3-2). Is referred to as “acid-stable monomer (a3-2)”, and acid-stable monomer (a3) represented by formula (a3-3) is referred to as “acid-stable monomer (a3-3)”.

In formula (a3-1), formula (a3-2) and formula (a3-3),
L ^a4 , L ^a5 and L ^a6 each independently represent —O— or ^* —O— (CH ₂ ) _k3 —CO—O—.
k3 represents an integer of 1 to 7. * Represents a bond with -CO-.
R ^a18 , R ^a19 and R ^a20 each independently represents a hydrogen atom or a methyl group.
R ^a21 represents an alkyl 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 alkyl 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 are independent of each other.

In formula (a3-1) to formula (a3-3), L ^{a4 to} L ^a6 are preferably each independently ^* —O— or ^* —O— (CH ₂ ) _d1 —CO—O— (here And d1 is an integer of 1 to 4, and more preferably —O—.
R ^{a18 to} R ^a21 are preferably methyl groups.
R ^a22 and R ^a23 are each independently preferably a carboxy group, a cyano group or a methyl group.
p1, q1 and r1 are each independently preferably an integer of 0 to 2, more preferably 0 or 1.

As an acid stable monomer (a3-1), the following are mentioned, for example.

Examples of the acid stable monomer (a3-2) include the following.

Examples of the acid stable monomer (a3-3) 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 More preferred are methacrylate esters.

  The resin (A) is a structural unit selected from the group consisting of a structural unit derived from the monomer (a3-1), a structural unit derived from the monomer (a3-2), and a structural unit derived from the monomer (a3-3) [ In the case of having the structural unit derived from the acid-stable monomer (a3)], the total content thereof is selected from the range of 5 to 50 moles with respect to 100 moles of all structural units of the resin (A), and 10 to 40 moles. Is preferable, and the range of 15 to 40 mol is more preferable.

<Other monomer (a4)>
Resin (A) may contain the structural unit derived from a well-known monomer other than the structural unit mentioned above.

  A preferred resin (A) is a copolymer obtained by polymerizing the monomer (a1), the acid stable monomer (a2) and / or the acid stable monomer (a3). In this preferable copolymer, it is preferable to use at least one of the above-mentioned monomer (a1-1) and monomer (a1-2) as monomer (a1), and it is more preferable to use monomer (a1-1). . The acid stable monomer (a2) is preferably an acid stable monomer (a2-1), and the acid stable monomer (a3) is at least one of an acid stable monomer (a3-1) and an acid stable monomer (a3-2). Is preferred.

Resin (A) uses monomer (a1) and, if necessary, acid-stable monomer selected from the group consisting of acid-stable monomer (a2) and acid-stable monomer (a3), and these are resins as described above It can be produced by a known polymerization method (for example, radical polymerization method) after adjusting the amount of use so that the content is suitable for all structural units of (A).
The weight average molecular weight of the resin (A) is preferably 2,500 or more, more preferably 3,000 or more. The upper limit of the weight average molecular weight is preferably 50,000 or less, and more preferably 30,000 or less. In addition, the weight average molecular weight here is calculated | required as a conversion value of a standard polystyrene reference | standard by gel permeation chromatography analysis, and the detailed analysis conditions of this analysis are explained in full detail in the Example of this application.

  In addition to the resin (A), a (co) polymer containing a structural unit derived from an acid stable monomer may be added to the resist composition of the present invention.

  In the resist composition of the present invention, the mass ratio of one or more polymers selected from the group consisting of the polymer (1) and the polymer (2) and the resin (A) is 0.1: 99.9 to 30:70 is mentioned, Preferably it is 0.1: 99.9-20: 80, More preferably, it is 0.5: 99.5-5: 95.

<Acid generator (B)>
The acid generator (B) is classified into a nonionic type and an ionic type.
Nonionic acid generators include organic halides, sulfonate esters (for example, 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4). -Sulfonates), sulfones (e.g. 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.

  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.

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

In 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 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. —CH ₂ — contained in the alicyclic hydrocarbon group may be replaced by —O—, —SO ₂ — or —CO—.
Z ⁺ represents an organic cation.

  Examples of the perfluoroalkyl group include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. It is done.

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の合計炭素数の上限は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の合計炭素数の上限は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及びＬ^b10は、それぞれ独立に、炭素数１〜１１の飽和炭化水素基を表す。但しＬ^b9及びＬ^b10の合計炭素数の上限は１２である。 Examples of the group in which —CH ₂ — contained in the divalent saturated hydrocarbon group is replaced by —O— or —CO— include, for example, the following formula (b1-1), formula (b1-2), and formula (b1 -3), formula (b1-4), formula (b1-5) and formula (b1-6) [hereinafter expressed as “formula (b1-1) to formula (b1-6)”. ] The group shown by either of these is mentioned. 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 a formula (b1-2). It is the group shown. Incidentally, the formula (b1-1) ~ formula (b1-6) is coupled to the left and right have been described in accordance with the formula (B1), the left bond * is a ^{C (Q 1) (Q 2} ) The right hand * is bonded to Y. The same applies to specific examples of the following formulas (b1-1) to (b1-6).

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 total 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 total 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 and L ^b10 each independently represent a saturated hydrocarbon group having 1 to 11 carbon atoms. However, the upper limit of the total carbon number of L ^b9 and L ^b10 is 12.

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.

Examples of the substituent that the alkyl group and the alicyclic hydrocarbon group may have include, for example, a halogen atom, a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, A aralkyl group having 7 to 21 carbon atoms, an acyl group having 2 to 4 carbon atoms, a glycidyloxy group or a group represented by — (CH ₂ ) _j2 —O—CO—R ^b1 (wherein R ^b1 is the number of carbon atoms) Represents an alkyl group having 1 to 16 carbon atoms, a saturated cyclic hydrocarbon group having 3 to 16 carbon atoms and an aromatic hydrocarbon group having 6 to 18 carbon atoms, j2 represents an integer of 0 to 4).
The aromatic hydrocarbon group and aralkyl group which are the substituents may have, for example, an alkyl group, a halogen atom or a hydroxy group.
Moreover, as a substituent of an alkyl group, a C3-C16 saturated cyclic hydrocarbon group may be sufficient.

In formula (B1), Q ¹ and Q ² are each independently preferably a trifluoromethyl group or a fluorine atom, and more preferably Q ¹ and Q ² are both fluorine atoms.
Further, -CH ₂ contained in the divalent saturated hydrocarbon group in L ^b1 - as those which have been replaced by -O- or -CO-, a divalent group represented by the formula (b1-1) is preferably In particular, a divalent group represented by the formula (b1-1) in which L ^b2 is a single bond or —CH ₂ — is more preferable.

Ｙとしては、中でも、式（Ｙ１）〜式（Ｙ１９）のいずれかで表される基が好ましく、式（Ｙ１１）、式（Ｙ１４）、式（Ｙ１５）又は式（Ｙ１９）で表される基がさらに好ましく、式（Ｙ１１）又は式（Ｙ１４）で表される基がより好ましい。 As the alkyl group for Y, an alkyl group having 1 to 6 carbon atoms is more preferable.
In particular, examples of the alicyclic hydrocarbon group for Y include groups represented by any of formulas (Y1) to (Y26). In the groups represented by these formulas (Y1) to (Y26), * represents a bond bonded to L ^b1 .

Among them, Y is preferably a group represented by any one of formulas (Y1) to (Y19), and is a group represented by formula (Y11), formula (Y14), formula (Y15), or formula (Y19). Is more preferable, and a group represented by Formula (Y11) or Formula (Y14) is more preferable.

Examples of Y include the following.

  Y is preferably an adamantyl group which may have a hydroxy group or the like as a substituent, and more preferably an adamantyl group or a hydroxyadamantyl group.

Examples of the sulfonate anion include sulfonate anions represented by formulas (b1-1-1) to (b1-1-9). In the sulfonate anion represented by any one of the formulas (b1-1-1) to (b1-1-9), L ^b2 , Q ¹ and Q ² are as defined above, and R ^b2 and R ^b3 is each independently an alkyl group having 1 to 4 carbon atoms, preferably a methyl group.

Examples of the sulfonate anion include the following.

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

More preferred sulfonate anions are shown below.

  Examples of the cation contained in the acid generator include an onium cation, 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.

As an organic cation (Z ^<+> ) in an acid generator (B1), an organic sulfonium cation and an organic iodonium cation are preferable, More preferably, in either of the following formula | equation (b2-1)-a formula (b2-4) Organic cation represented [hereinafter, according to the number of each formula, "cation (b2-1)", "cation (b2-2)", "cation (b2-3)" and "cation (b2-4) There are times. ].

In formula (b2-1) to formula (b2-4),
R ^b4 , R ^b5 and R ^b6 each independently represent 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 18 carbon atoms, The hydrogen atom contained in the alkyl 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 is included in the alicyclic hydrocarbon group. The hydrogen atom may be substituted with a halogen atom, an acyl group having 2 to 4 carbon atoms or a glycidyloxy group, and the aromatic hydrocarbon group is a halogen atom, a hydroxy group, or an alkyl group having 1 to 18 carbon atoms. , May be substituted with a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms 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.
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. R ^b9 and R ^b10 may be bonded to each other to form a 3- to 12-membered ring (preferably a 3- to 7-membered ring), and —CH ₂ — contained in the ring May be replaced by -O-, -S- 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, and the aromatic hydrocarbon group has It may be substituted with an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms, or an alkylcarbonyloxy group having 1 to 12 carbon atoms.
R ^b11 and R ^b12 may be bonded to each other to form a 3- to 12-membered ring (preferably a 3- to 7-membered ring), and —CH ₂ — contained in the ring is -O-, -S- or -CO- may be substituted.

^{R b13, R b14, R b15} , R b16, R b17 and R ^b18 each independently represent a hydroxy group, an alkyl group or an alkoxy group having 1 to 12 carbon atoms 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 o2 is 2 or more, the plurality of R ^b13 are each independent. When p2 is 2 or more, the plurality of R ^b14 may be the same or different. When s2 is 2 or more, the plurality of R ^{b15 May be} the same or different, and when t2 is 2 or more, the plurality of R ^b18 may be the same or different.

  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.

Among the alkyl groups ^{represented by} R ^{b9 to} R ^b12 , preferred groups are, for example, 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. In particular, the alkyl group of R ^b9 , R ^b10 and R ^b11 preferably has 1 to 12 carbon atoms. ^{Preferred examples} of the alicyclic hydrocarbon group ^{represented by} R ^{b9 to} R ^b12 include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclodecyl group, a 2-alkyladamantan-2-yl group, 1- (adamantan-1-yl) alkane-1-yl group and isobornyl group. In particular, the alicyclic hydrocarbon group of R ^b9 , R ^b10 and R ^b11 preferably has 3 to 18 carbon atoms, and more preferably 4 to 12 carbon atoms.
^{Preferred examples} of the aromatic hydrocarbon group for R ^b12 include a phenyl group, a 4-methylphenyl group, a 4-ethylphenyl group, a 4-tert-butylphenyl group, a 4-cyclohexylphenyl group, and 4-methoxy. A phenyl group, a biphenylyl group, a naphthyl group, and the like;
Examples of the ring formed by combining 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. Is mentioned.
Examples of the ring formed by combining R ^b11 and R ^b12 include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

式（ｂ２−１−１）中、
Ｒ^b19、Ｒ^b20及び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１〜１８のアルキル基、炭素数３〜１８の脂環式炭化水素基又は炭素数１〜１２のアルコキシ基を表す。
アルキル基は、炭素数は１〜１２が好ましく、炭素数１〜１２のアルキル基がより好ましい。さらには置換基として、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を有していてもよい。
また、脂環式炭化水素基の炭素数は４〜１８であると好ましい。置換基として、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を有していてもよい。
ｖ２、ｗ２及び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が２以上のとき、複数のＲ^b19はそれぞれ独立であり、ｗ２が２以上のとき、複数のＲ^b20はそれぞれ独立であり、ｘ２が２以上のとき、複数のＲ^b21はそれぞれ独立である。
なかでも、Ｒ^b19、Ｒ^b20及び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。 Among the exemplified organic cations, the cation (b2-1) is preferable, and an organic cation represented by the following formula (b2-1-1) [hereinafter referred to as “cation (b2-1-1)”. ], More preferably a triphenylsulfonium cation (in formula (b2-1-1), v2 = w2 = x2 = 0) or a tolylsulfonium cation (in formula (b2-1-1), v2 = w2 = X2 = 1, and R ^b19 , R ^b20 and R ^b21 are all methyl groups).

In formula (b2-1-1),
R ^b19 , R ^b20 and R ^b21 each independently represent a halogen atom (more preferably a fluorine atom), a hydroxy group, an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or carbon. The number 1-12 alkoxy group is represented.
The alkyl group preferably has 1 to 12 carbon atoms, and more preferably has 1 to 12 carbon atoms. Furthermore, as a substituent, you may have a hydroxyl group, a C1-C12 alkoxy group, or a C6-C18 aromatic hydrocarbon group.
The alicyclic hydrocarbon group preferably has 4 to 18 carbon atoms. As a substituent, you may have a halogen atom, a C2-C4 acyl group, or a glycidyloxy group.
v2, w2 and x2 each independently represent an integer of 0 to 5 (preferably 0 or 1).
When v2 is 2 or more, each of the plurality of R ^b19 is independent. When w2 is 2 or more, each of the plurality of R ^b20 is independent. When x2 is 2 or more, each of the plurality of R ^b21 is independent. .
Among them, R ^b19 , R ^b20 and 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. It is.

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 a sulfonate anion and an organic cation. The sulfonate anion and the organic cation can be arbitrarily combined, but the sulfonate anion and the cation (b2-1-1) represented by any one of the formulas (b1-1-1) to (b1-1-9) can be used. 1) a combination of an acid generator (B1) and a sulfonate anion and a cation (b2-3) represented by any one of formulas (b1-1-3) to (b1-1-5) A combination acid generator (B1) is preferred.

More preferred acid generator (B1) is specifically shown. Such an acid generator (B1) is represented by any of the following formulas (B1-1) to (B1-17). Among them, the acid generator (B1) containing a triphenylsulfonium cation or a tolylsulfonium cation is a formula (B1-1), a formula (B1-2), a formula (B1-6), a formula (B1-11), a formula Those represented by any of (B1-12), formulas (B1-13) and (B1-14) are more preferred.

<Basic Compound (hereinafter referred to as “Basic Compound (C)”)>
The resist composition may contain a basic compound (C). The “basic compound” means a compound having a property of scavenging an acid, particularly a compound having a property of scavenging an acid generated from the acid generator described above, and is referred to as a quencher in this technical field. ing.

式中、Ａｒ^c1は、芳香族炭化水素基を表す。
Ｒ^c5及びＲ^c6は、それぞれ独立に、水素原子、アルキル基（好ましくは、炭素数１〜６程度のアルキル基）、脂環式炭化水素基（好ましくは、炭素数５〜１０程度の脂環式炭化水素基）又は芳香族炭化水素基（好ましくは、炭素数６〜１０程度の芳香族炭化水素基）を表し、該アルキル基、該脂環式炭化水素基及び該芳香族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、アミノ基はさらに、炭素数１〜４のアルキル基で置換されていてもよい。
Ｒ^c7は、アルキル基（好ましくは、炭素数１〜６程度のアルキル基）、炭素数１〜６程度のアルコキシ基、脂環式炭化水素基（好ましくは、炭素数５〜１０程度の脂環式炭化水素基、さらに好ましくは、炭素数５〜１０程度のシクロアルキル基）又は芳香族炭化水素基（好ましくは、炭素数６〜１０程度の芳香族炭化水素基）を表し、前記アルキル基、アルコキシ基、脂環式炭化水素基及び芳香族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、アミノ基はさらに、炭素数１〜４のアルキル基で置換されていてもよい。
ｍ３は０〜３の整数を表す。ｍ３が２以上のとき、複数のＲ^c7は同一でも異なってもよい。 The basic compound (C) is preferably a basic nitrogen-containing organic compound, and examples thereof include amines and ammonium hydroxides. The amine may be an aliphatic amine or an aromatic amine. The aliphatic amine may be any of primary amine, secondary amine and tertiary amine. The aromatic amine may be either an aromatic ring such as aniline with an amino group bonded thereto or a heteroaromatic amine such as pyridine. Preferable basic compounds (C) include aromatic amines represented by the following formula (C2), particularly anilines represented by the following formula (C2-1).

In the formula, Ar ^c1 represents an aromatic hydrocarbon group.
R ^c5 and R ^c6 each independently represent a hydrogen atom, an alkyl group (preferably an alkyl group having about 1 to 6 carbon atoms), or an alicyclic hydrocarbon group (preferably an alicyclic group having about 5 to 10 carbon atoms). Type hydrocarbon group) or an aromatic hydrocarbon group (preferably an aromatic hydrocarbon group having about 6 to 10 carbon atoms), and the alkyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group The hydrogen atom contained 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 further substituted with an alkyl group having 1 to 4 carbon atoms.
R ^c7 is an alkyl group (preferably an alkyl group having about 1 to 6 carbon atoms), an alkoxy group having about 1 to 6 carbon atoms, or an alicyclic hydrocarbon group (preferably an alicyclic group having about 5 to 10 carbon atoms). A hydrocarbon group, more preferably a cycloalkyl group having about 5 to 10 carbon atoms) or an aromatic hydrocarbon group (preferably an aromatic hydrocarbon group having about 6 to 10 carbon atoms), the alkyl group, The hydrogen atom contained in the alkoxy group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be substituted with a hydroxy group, an amino group or an alkoxy group having 1 to 6 carbon atoms. It may be substituted with an alkyl group of formulas 1-4.
m3 represents an integer of 0 to 3. When m3 is 2 or more, the plurality of R ^c7 may be the same or different.

Examples of the aromatic amine represented by the formula (C2) include 1-naphthylamine and 2-naphthylamine.
The anilines represented by the formula (C2-1) include, for example, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N, N-dimethylaniline and diphenylamine. Etc.

式中、
Ｒ^c8、Ｒ^c20、Ｒ^c21、Ｒ^c23、Ｒ^c24、Ｒ^c25、Ｒ^c26、Ｒ^c27及びＲ^c28は前記Ｒ^c7と同義のものである。
Ｒ^c9、Ｒ^c10、Ｒ^c11、Ｒ^c12、Ｒ^c13、Ｒ^c14、Ｒ^c16、Ｒ^c17、Ｒ^c18、Ｒ^c19及びＲ^c22は、それぞれ独立に、前記のＲ^c5及びＲ^c6と同義のものである。
ｏ３、ｐ３、ｑ３、ｒ３、ｓ３、ｔ３及びｕ３は、それぞれ独立に０〜３の整数を表す。ｏ３が２以上であるとき、複数のＲ^c20は同一でも異なってもよく、ｐ３が２以上であるとき、複数のＲ^c21は同一でも異なってもよく、ｑ３が２以上であるとき、複数のＲ^c24は同一でも異なってもよく、ｒ３が２以上であるとき、複数のＲ^c25は同一でも異なってもよく、ｓ３が２以上であるとき、複数のＲ^c26は同一でも異なってもよく、ｔ３が２以上であるとき、複数のＲ^c27は同一でも異なってもよく、ｕ３が２以上であるとき、複数のＲ^c28は同一でも異なってもよい。 Moreover, you may use the compound represented by either of the following formula | equation (C3)-a formula (C11).

Where
R ^c8 , R ^c20 , R ^c21 , R ^c23 , R ^c24 , R ^c25 , R ^c26 , R ^c27 and R ^c28 are as defined above for R ^c7 .
R ^c9 , R ^c10 , R ^c11 , R ^c12 , R ^c13 , R ^c14 , R ^c16 , R ^c17 , R ^c18 , R ^c19 and R ^c22 are each independently synonymous with R ^c5 and R ^c6 above. is there.
o3, p3, q3, r3, s3, t3 and u3 each independently represents an integer of 0 to 3. When o3 is 2 or more, the plurality of R ^c20 may be the same or different, and when p3 is 2 or more, the plurality of R ^c21 may be the same or different, and when q3 is 2 or more, R ^c24 may be the same or different. When r3 is 2 or more, a plurality of R ^c25 may be the same or different. When s3 is 2 or more, a plurality of R ^c26 may be the same or different. When t3 is 2 or more, the plurality of R ^c27 may be the same or different, and when ^u3 is 2 or more, the plurality of R ^c28 may be the same or different.

R ^c15 is an alkyl group (preferably an alkyl group having about 1 to 6 carbon atoms), an alicyclic hydrocarbon group (preferably an alicyclic hydrocarbon group having about 3 to 6 carbon atoms) or an alkanoyl group (preferably Represents an alkanoyl group having about 2 to 6 carbon atoms.
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.
L ^c1 and L ^c2 are each independently a divalent alkanediyl group (preferably an alkanediyl group having about 1 to 6 carbon atoms), —CO—, —C (═NH) —, —C (═NR ^c3 )-(wherein R ^c3 represents an alkyl group having 1 to 4 carbon atoms), -S-, -SS-, or a combination thereof.
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 (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, Examples include 4'-dipyridyl disulfide, 2,2'-dipyridylamine, and 2,2'-dipicolylamine.
Examples of compound (C11) include bipyridine.

  Examples of the basic compound (C3) include hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropyl Amine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, Methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyl Dihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine ethylenediamine, tetramethylenediamine, hexa Use methylenediamine, 4,4′-diamino-1,2-diphenylethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane, etc. Can do.

  Specific examples of ammonium hydroxide include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3- (trifluoromethyl ) Phenyltrimethylammonium hydroxide and choline.

  Of these, diisopropylaniline is preferred as the basic compound (C) used in the resist composition, and 2,6-diisopropylaniline is particularly preferred.

<Solvent (hereinafter referred to as “solvent (E)”)>
The solvent (E) contained in the resist composition is applied when the resist composition is applied on the substrate in the production of a resist pattern, which will be described later, according to the type and amount of each component contained in the resist composition. From the standpoint of good properties, an optimal one can be selected as appropriate.

  Examples of suitable solvents (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 Examples thereof include esters such as ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone; and cyclic esters such as γ-butyrolactone. Only 1 type may be used for a solvent (E) and it may use 2 or more types together.

<Other ingredients>
The resist composition may contain components other than those described above as necessary. This component is referred to as “component (F)”. Examples of the component (F) include additives known in the art, such as a sensitizer, a dissolution inhibitor, a surfactant, a stabilizer, and a dye.

<Resist composition and its preparation method>
The resist composition can be prepared by mixing each component. Further, the component (F) may be mixed as described above. In mixing, the order of mixing is arbitrary and is not particularly limited. The temperature and time for mixing can be appropriately selected from an appropriate temperature range, for example, 10 to 40 ° C. and 0.5 to 24 hours. The mixing means is not particularly limited, and stirring and mixing can be used.

The content of the solvent (E) is preferably 90 parts by mass or more, more preferably 92 parts by mass or more, and still more preferably 94 parts by mass or more with respect to 100 parts by mass of the resist composition. The upper limit of the content of the solvent (E) is, for example, 99.9 parts by mass or less, preferably 99 parts by mass or less.
The content of the solvent (E) can be controlled by the amount of the solvent (E) used when preparing the resist composition.

  The total content of the resin (A) and the polymer (1) and / or the polymer (2) with respect to the resist composition is 80 parts by mass or more with respect to 100 parts by mass of the total mass of the solid content of the resist composition. 99 mass% or less is preferable. Here, the total mass of the solid content of the resist composition means an amount obtained by removing the content of the solvent (E) from the total mass of the resist composition.

  The content of the acid generator (B) with respect to the resist composition is preferably 1 part by mass or more and more preferably 3 parts by mass with respect to 100 parts by mass of the total mass of the resin (A) contained in the resist composition. It is above, Preferably it is 30 mass parts or less, More preferably, it is 25 mass parts or less.

  When the basic compound (C) is used for the resist composition, the content of the basic compound (C) is 0.01 to 100 parts by mass with respect to the total mass of the solid content of the resist composition. About 1 part by mass is preferable.

  The solvent content of the resist composition, the total mass of the solid content, and the content of each component relative thereto can be determined by a known analysis means such as liquid chromatography or gas chromatography even after the resist composition is prepared. Can be measured.

  In addition, when using a component (F) for a resist composition, appropriate content can also be adjusted according to the kind of the said component (F).

  Thus, after mixing each structural component with preferable content, a resist composition can be prepared by filtering etc. using a filter with a pore diameter of about 0.01 to 0.2 μm.

<Method for producing resist pattern>
The method for producing a resist pattern of the present invention comprises:
(1) A step of applying a resist composition on a substrate,
(2) forming a composition layer on the substrate by drying the resist composition applied on the substrate;
(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.

  Application of the resist composition on the substrate in the step (1) can be performed by a coating apparatus widely used for applying a resist material for semiconductor microfabrication, such as a spin coater. In this way, a coating film made of a resist composition is formed on the substrate. The film thickness of the coating film can be adjusted by variously adjusting the conditions (coating conditions) of the coating apparatus, and by applying an appropriate preliminary experiment, the coating film can be applied to have a desired film thickness. You can choose the conditions. Various substrates to be subjected to microfabrication can be selected as the substrate before applying the resist composition. The substrate may be washed or an antireflection film may be formed before applying the resist composition. For example, a commercially available composition for an organic antireflection film can be used for forming the antireflection film.

In step (2), the resist composition coated on the substrate, that is, the coating film is dried to remove the solvent [solvent (E)]. Such solvent removal is performed by evaporating the solvent from the coating film by, for example, heating means using a heating device such as a hot plate (so-called pre-baking), decompressing means using a decompressing device, or a combination of these means. Is done. The conditions of the heating means and the decompression means are adjusted according to the type of the solvent (E) contained in the resist composition. For example, in the heating means using a hot plate, the surface temperature of the hot plate is 50 to 200 ° C. It should be in the range of about. In the decompression means, after the substrate on which the coating film is formed is sealed in an appropriate decompressor, the internal pressure of the decompressor may be set to about 1 to 1.0 × 10 ⁵ Pa. By drying the coating film in this manner, a composition layer is formed on the substrate.

Step (3) is a step of exposing the composition layer, and preferably the composition layer is exposed using an exposure machine. At this time, exposure is performed through a photomask corresponding to a desired pattern to be finely processed. As an exposure light source of the exposure machine, an ultraviolet light source such as a KrF excimer laser (wavelength 248 nm), an ArF excimer laser (wavelength 193 nm), an F ₂ excimer laser (wavelength 157 nm), or a solid-state laser light source (YAG Various lasers such as those that emit laser light from a far ultraviolet region or a vacuum ultraviolet region by converting the wavelength of laser light from a semiconductor laser or the like can be used. Further, the exposure machine may be an immersion exposure machine, or may irradiate an electron beam or extreme ultraviolet light (EUV).

  As described above, exposure through a photomask results in an exposed portion (exposed portion) and an unexposed portion (unexposed portion) in the composition layer. In the composition layer of the exposed portion, the acid generator (B) contained in the composition layer generates an acid upon receiving exposure energy, and further, an acid labile group in the resin (A) is generated by the action with the generated acid. Since a hydrophilic group is generated by the deprotection reaction, the resin (A) in the composition layer of the exposed portion becomes soluble in the alkaline aqueous solution. On the other hand, since the exposure energy is not received in the unexposed area, the resin (A) remains insoluble or hardly soluble in the alkaline aqueous solution. Thus, the composition layer in the exposed portion and the composition layer in the unexposed portion are significantly different in solubility in the alkaline aqueous solution.

  In step (4), the composition layer after exposure is subjected to heat treatment (so-called post-exposure baking). For the heat treatment, the heating means using the hot plate shown in the step (2) is adopted. In the heating means using a hot plate in step (4), the surface temperature of the hot plate is preferably about 50 to 200 ° C, more preferably about 70 to 150 ° C. Such a heat treatment promotes the deprotection reaction.

Step (5) is a step of developing the heated composition layer, and preferably the heated composition layer is developed with a developing device. The development here refers to dissolving the exposed composition layer in the alkaline aqueous solution by bringing the heated composition layer into contact with the alkaline aqueous solution and leaving the unexposed composition layer on the substrate. With this, a resist pattern can be formed on the substrate.
As the alkaline aqueous solution used here, a solution known in the technical field called “alkaline developer” can be used. Examples of the alkaline aqueous solution include an aqueous solution of tetramethylammonium hydroxide and an aqueous solution of (2-hydroxyethyl) trimethylammonium hydroxide (commonly called choline).

  The resist pattern manufactured on the substrate as described above is preferably rinsed with ultrapure water or the like to further remove moisture remaining on the substrate and the resist pattern.

<Application>
The resist composition of the present invention includes a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) irradiation or a resist composition for EUV exposure, and a liquid It is suitable as a resist composition for immersion exposure.

The present invention will be described more specifically with reference to the following examples.
In Examples and Comparative Examples, “%” and “part” representing the content or amount used are based on mass unless otherwise specified.
The weight average molecular weight is a value obtained by gel permeation chromatography (HLC-8120GPC type manufactured by Tosoh Corporation, column is TSKgel Multipore HXL-M3, solvent is tetrahydrofuran) using polystyrene as a standard product.
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).
The molar ratio of each structural unit of the polymer and the resin is determined by LC-IS method (LC-2010A manufactured by Shimadzu Corp., YMC-PAC manufactured by YMC Corp.). C4 column, solvent: acetonite, water), and each monomer was calculated by subtracting from the amount of monomer added first, by the molar ratio.

[Synthesis of Compound Represented by Formula (I-61)]

  To a solution of 10.0 parts of the compound represented by the formula (I-61-a) and 25 parts of acetonitrile, 8.4 parts of the compound represented by the formula (I-61-b) is added and heated under reflux for 20 hours. Went. 30 parts of ion-exchanged water was added to the reaction mixture solution, and extraction was performed with 100 parts of ethyl acetate. To the obtained organic layer containing ethyl acetate, 30 parts of 10% potassium carbonate aqueous solution was added and stirred overnight, and then the aqueous layer was discharged. The obtained organic layer was washed with ion-exchanged water and concentrated under reduced pressure to obtain 11.5 parts of a compound represented by the formula (I-61).

¹ H-NMR (CDCl ₃ ): δ = 7.4-7.6 (5H, m), 5.9-6.1 (1H, brs), 3.5-3.7 (1H, m), 1.9-2.1 (2H, m), 1.1-1.8 (8H, m)

[Synthesis of Compound Represented by Formula (I-63)]

  In a solution of 50.0 parts of the compound represented by the formula (I-63-a) and 250 parts of acetonitrile, 18.9 parts of the compound represented by the formula (I-63-b) and 0.1 part of triethylamine And stirred at room temperature for 3 hours. 100 parts of ion exchange water was added to the reaction mixture solution, and extraction was performed with 300 parts of ethyl acetate. The obtained organic layer was concentrated under reduced pressure to obtain 45.7 parts of a compound represented by the formula (I-63).

_{^{1 H-NMR (CDCl 3)}} : δ = 7.59-7.31 (5H, m), 6.55-6.38 (1H, brm), 6.15-6.10 (1H, m), 5.64-5.59 (1H, m), 4.31 (2H, t, J = 5.4 Hz), 3.64 (2H, q, J = 5.4 Hz) 1.97-1.93 ( 3H, m)
MS (ESI (+) Spectrum) : [M + Na] ^{_{+ 444.1 (C 17 H 15 F}} 7 N 2 O 4 = 444.1)

[Synthesis of Compound Represented by Formula (I-113)]

  In a solution of 10.0 parts of the compound represented by the formula (I-113-a) and 40 parts of acetonitrile, 9.4 parts of the compound represented by the formula (I-113-b) and 0.1 part of triethylamine And stirred at room temperature for 3 hours. 20 parts of ion-exchanged water was added to the reaction mixture solution, and extraction was performed with 80 parts of ethyl acetate. The obtained organic layer was concentrated under reduced pressure to obtain 18.7 parts of a compound represented by the formula (I-113).

¹ H-NMR (CDCl ₃ ): δ = 6.7-6.5 (1H, brm), 6.2-6.1 (1H, m), 5.6-5.5 (1H, m), 4.3 (2H, t, J = 5.6 Hz), 3.7-3.5 (2H, m), 2.7-2.5 (1H, m), 2.1-1.7 (16H) , M)

[Synthesis of Compound Represented by Formula (III-61)]

  In a solution of 50.0 parts of the compound represented by the formula (III-61-a) and 250 parts of tetrahydrofuran, 29.4 parts of N-methylpyrrolidone and the compound represented by the formula (III-61-b) 48. 9 parts was added and stirred at room temperature for 3 hours. 63 parts of a 5% hydrochloric acid aqueous solution and 200 parts of ion-exchanged water were added to the reaction mixture solution, and extraction was performed with 500 parts of ethyl acetate. To the obtained organic layer containing ethyl acetate, 146 parts of a 10% aqueous potassium carbonate solution was added, stirred overnight, and the aqueous layer was discharged. The obtained organic layer was washed with ion-exchanged water and concentrated under reduced pressure to obtain 66.2 parts of a compound represented by the formula (III-61).

¹ H-NMR (DMSO-d ₆ ): δ = 7.66-7.52 (5H, m), 5.85-5.82 (1H, m), 5.80-5.76 (1H, m ), 1.81-1.76 (3H, m)
MS (ESI (+) Spectrum): [M + Na] ⁺ 280.1 (C ₁₂ H ₁₀ F ₃ NO ₂ = 257.1)

[Synthesis of Compound Represented by Formula (III-63)]

  In a solution of 42.3 parts of the compound represented by formula (III-63-a) and 170 parts of ethyl acetate, 13.7 parts of N-methylpyrrolidone and compound 24 represented by formula (III-63-b) And 8 parts were added and stirred at room temperature for 3 hours. 35 parts of 5% hydrochloric acid aqueous solution and 135 parts of ion-exchanged water were added to the reaction mixture, and extraction was performed with 330 parts of ethyl acetate. To the obtained organic layer containing ethyl acetate, 111 parts of 10% aqueous potassium carbonate solution was added and stirred overnight, and the aqueous layer was discharged. The obtained organic layer was washed with ion-exchanged water and concentrated under reduced pressure to obtain 52.3 parts of a compound represented by the formula (III-63).

¹ H-NMR (DMSO-d ₆ ): δ = 7.65-7.51 (5H, m), 5.75-5.82 (2H, m), 3.05 (3H, s)
_{^{MS (ESI (+) Spectrum)}} : M + 357.1 (C 14 H 10 F 7 NO 2 = 357.1)

式（ＩＶ−１−ａ）で表される化合物（出光興産社製）２．００部及びヘプタフルオロ酪酸無水物８．００部を仕込み、１２０℃で１５時間攪拌し、２３℃まで冷却した。得られた反応物に、クロロホルム１００部及び５％炭酸水素ナトリウム水溶液６６部を加えて２３℃で３０分間攪拌し、分液した。回収された有機層に、イオン交換水５６部を仕込み２３℃で３０分間攪拌し、分液することにより有機層を回収した。この水洗の操作を４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、式（ＩＶ−１）で表される化合物１．８５部を得た。 [Synthesis of Compound Represented by Formula (IV-1)]

2.00 parts of a compound represented by formula (IV-1-a) (Idemitsu Kosan Co., Ltd.) and 8.00 parts of heptafluorobutyric anhydride were charged, stirred at 120 ° C. for 15 hours, and cooled to 23 ° C. To the obtained reaction product, 100 parts of chloroform and 66 parts of 5% aqueous sodium hydrogen carbonate solution were added, stirred at 23 ° C. for 30 minutes, and separated. The recovered organic layer was charged with 56 parts of ion exchange water, stirred at 23 ° C. for 30 minutes, and separated to recover the organic layer. This washing operation was performed 4 times. The recovered organic layer is concentrated, 20 parts of methyl t-butyl ether is added to the obtained concentrate, and the mixture is stirred at 23 ° C. for 3 hours and filtered to obtain a solid represented by the formula (IV-1). 1.85 parts of the following compound were obtained.

MS (ESI (+) Spectrum) : M + III644.1 (C 22 H 18 F 14 O 6 = 644.1)

式（ＶＩ−１−ａ）で表される化合物（セントラル硝子社製）３０部、メチルイソブチルケトン９０部及びＮ−メチルピロリジン１１．４０部を仕込み、２３℃で３０分間攪拌した。これにピバロイルクロリド１２．９１部を３０分かけて滴下した。３０℃で４時間攪拌した。これにメチルイソブチルケトン６０部及びイオン交換水３０部を添加し、攪拌し、分液を行った。回収された有機層に、イオン交換水３０部を添加し、攪拌し、分液を行った。この水洗の操作を４回行った。回収された有機層を濃縮し、濃縮液をカラム（関東化学 シリカゲル６０Ｎ（球状、中性）１００−２１０μｍ 展開溶媒：ｎ−ヘプタン／酢酸エチル＝５０／１）分取することにより、式（ＶＩ−１）で表される化合物２０．９５部を得た。 [Synthesis of Compound Represented by Formula (VI-1)]

30 parts of a compound represented by the formula (VI-1-a) (manufactured by Central Glass Co., Ltd.), 90 parts of methyl isobutyl ketone and 11.40 parts of N-methylpyrrolidine were charged and stirred at 23 ° C. for 30 minutes. To this, 12.91 parts of pivaloyl chloride was added dropwise over 30 minutes. Stir at 30 ° C. for 4 hours. To this, 60 parts of methyl isobutyl ketone and 30 parts of ion-exchanged water were added, stirred and separated. To the recovered organic layer, 30 parts of ion-exchanged water was added, stirred and separated. This washing operation was performed 4 times. The collected organic layer is concentrated, and the concentrated solution is separated by a column (Kanto Kagaku Silica Gel 60N (spherical, neutral) 100-210 μm developing solvent: n-heptane / ethyl acetate = 50/1). The compound represented by -1) was obtained 20.95 parts.

_{MS (ESI (+) Spectrum)} : M + 420.2 (C 18 H 26 F 6 O 4 = 420.2)

(Synthesis of resin)
The monomers used for the synthesis of the resin are shown below.

Polymer (1): Synthesis of (D1) In a four-necked flask equipped with a condenser, a stirrer, and a thermometer, 3.0 parts of 1,4-dioxane was charged and kept at 72 ° C. 10.0 parts of the compound represented by formula (I-61), 0.07 parts of 2,2′-azobis (isobutyronitrile) and 2,2′-azobis (2,4-dimethylvaleronitrile) 32 parts were dissolved in 22.9 parts of 1,4-dioxane and 2.0 parts of tetrahydrofuran to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained liquid mixture was thrown into 130 parts of n-heptane. The precipitated polymer was dried at 40 ° C. under reduced pressure to obtain 9.4 parts of a polymer. The polymer has the following structural units.
Weight average molecular weight 9.6 × 10 ³ , Mw / Mn 1.9

Polymer (2): Synthesis of (D2) 3.3 parts of 1,4-dioxane was charged into a four-necked flask equipped with a condenser, a stirrer, and a thermometer, and kept at 72 ° C. 4.7 parts of the compound represented by the formula (I-61), 6.2 parts of the compound represented by the formula (III-61), 0.09 parts of 2,2′-azobis (isobutyronitrile) and 2 parts , 2′-azobis (2,4-dimethylvaleronitrile) 0.42 part was dissolved in 1,4-dioxane 13.2 part to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The resulting mixture was diluted with 12.1 parts of 1,4-dioxane and then charged into 143 parts of n-heptane. The precipitated polymer was dried at 40 ° C. under reduced pressure to obtain 10.9 parts of a polymer. The polymer has the following structural units.
Weight average molecular weight 1.4 × 10 ⁴ , Mw / Mn 2.7,
Molar ratio (I-61) :( III-61) = 36: 64

Polymer (2): Synthesis of (D3) Into a four-necked flask equipped with a condenser, a stirrer, and a thermometer, 3.6 parts of 1,4-dioxane was charged and kept at 72 ° C. 6.0 parts of the compound represented by formula (I-61), 6.1 parts of the compound represented by formula (IV-1), 0.07 parts of 2,2′-azobis (isobutyronitrile) and 2 parts , 2'-azobis (2,4-dimethylvaleronitrile) 0.30 part was dissolved in 14.5 parts of 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed solution was diluted with 13.3 parts of 1,4-dioxane and charged into a mixed solvent consisting of 125 parts of methanol and 31 parts of water. The precipitated polymer was dissolved in 31 parts of 1,4-dioxane and charged into 157 parts of n-heptane. The precipitated polymer was dried under reduced pressure at 40 ° C. to obtain 10.6 parts of the polymer. The polymer has the following structural units.
Weight average molecular weight 2.2 × 10 ⁴ , Mw / Mn 2.6,
Molar ratio (I-61) :( IV-1) = 65: 35

Polymer (2): Synthesis of (D4) Into a four-necked flask equipped with a condenser, a stirrer, and a thermometer, 1.8 parts of 1,4-dioxane was charged and kept at 72 ° C. 8.0 parts of the compound represented by formula (I-61), 3.7 parts of the compound represented by formula (IV-1), 0.07 parts of 2,2′-azobis (isobutyronitrile) and 2 parts , 2′-azobis (2,4-dimethylvaleronitrile) 0.33 part was dissolved in 15.9 parts of 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed solution was diluted with 12.9 parts of 1,4-dioxane, and charged into a mixed solvent consisting of 122 parts of methanol and 31 parts of water. The precipitated polymer was dissolved in 31 parts of 1,4-dioxane and charged into 153 parts of n-heptane. The precipitated polymer was dried under reduced pressure at 40 ° C. to obtain 10.7 parts of the polymer. The polymer has the following structural units.
Weight average molecular weight 2.2 × 10 ⁴ , Mw / Mn 2.6,
Molar ratio (I-61) :( IV-1) = 80: 20

Polymer (2): Synthesis of (D5) 1.4 parts of 1,4-dioxane was charged into a four-necked flask equipped with a condenser, a stirrer, and a thermometer, and kept at 72 ° C. 6.5 parts of the compound represented by formula (I-61), 2.7 parts of the compound represented by formula (VI-1), 0.08 parts of 2,2′-azobis (isobutyronitrile) and 2 parts , 2'-azobis (2,4-dimethylvaleronitrile) 0.38 part was dissolved in 12.4 parts of 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed solution was diluted with 10.1 parts of 1,4-dioxane and charged into a mixed solvent of 95 parts of methanol and 24 parts of water. The precipitated polymer was dissolved in 24 parts of 1,4-dioxane and charged into 119 parts of n-heptane. The precipitated polymer was dried under reduced pressure at 40 ° C. to obtain 7.0 parts of a polymer. The polymer has the following structural units.
Weight average molecular weight 1.3 × 10 ⁴ , Mw / Mn 1.9,
Molar ratio (I-61) :( VI-1) = 79: 21

Polymer (2): Synthesis of (D6) A 4-necked flask equipped with a condenser, a stirrer, and a thermometer was charged with 3.2 parts of 1,4-dioxane and kept at 72 ° C. 4.3 parts of the compound represented by the formula (I-63), 6.4 parts of the compound represented by the formula (III-63), 0.09 parts of 2,2′-azobis (isobutyronitrile) and 2 , 2′-azobis (2,4-dimethylvaleronitrile) 0.41 part was dissolved in 12.8 parts of 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed liquid was put into 139 parts of n-heptane. The precipitated polymer was dried under reduced pressure at 40 ° C. to obtain 7.1 parts of a polymer. The polymer has the following structural units.
Weight average molecular weight 1.1 × 10 ⁴ , Mw / Mn 1.9,
Molar ratio (I-63) :( III-63) = 35: 65

Synthesis of polymer (2) (D7) Into a four-necked flask equipped with a condenser, a stirrer, and a thermometer, 3.3 parts of 1,4-dioxane was charged and kept at 72 ° C. 1.3 parts of the compound represented by formula (I-63), 9.6 parts of the compound represented by formula (III-63), 0.10 parts of 2,2′-azobis (isobutyronitrile) and 2 parts , 2′-azobis (2,4-dimethylvaleronitrile) 0.45 part was dissolved in 13.4-parts of 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained liquid mixture was thrown into 143 parts of n-heptane. The precipitated polymer was dried at 40 ° C. under reduced pressure to obtain 9.3 parts of polymer. The polymer has the following structural units.
Weight average molecular weight 2.7 × 10 ⁴ , Mw / Mn 2.9,
Molar ratio (I-63) :( III-63) = 10: 90

Polymer (2): Synthesis of (D8) A 4-necked flask equipped with a condenser, a stirrer, and a thermometer was charged with 3.3 parts of 1,4-dioxane and kept at 72 ° C. 0.6 parts of the compound represented by formula (I-61), 6.3 parts of the compound represented by formula (IV-1), 4.2 parts of the compound represented by formula (III-61), 2, A solution obtained by dissolving 0.06 part of 2′-azobis (isobutyronitrile) and 0.27 part of 2,2′-azobis (2,4-dimethylvaleronitrile) in 13.3 parts of 1,4-dioxane. Got. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed liquid was put into 145 parts of n-heptane. The precipitated polymer was dried at 40 ° C. under reduced pressure to obtain 9.3 parts of polymer. The polymer has the following structural units.
Weight average molecular weight 1.8 × 10 ⁴ , Mw / Mn 1.9,
Molar ratio (I-61) :( IV-1) :( III-61) = 50: 40: 10

Polymer (2): Synthesis of (D9) Into a four-necked flask equipped with a condenser, a stirrer, and a thermometer, 3.3 parts of 1,4-dioxane was charged and kept at 72 ° C. 2.9 parts of the compound represented by formula (I-61), 6.3 parts of the compound represented by formula (IV-1), 0.6 part of the compound represented by formula (III-61), 1.0 part of a compound represented by a3-2-1), 0.06 part of 2,2′-azobis (isobutyronitrile) and 2,2′-azobis (2,4-dimethylvaleronitrile) 27 parts was dissolved in 13.1 parts of 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed liquid was put into 141 parts of n-heptane. The precipitated polymer was dried at 40 ° C. under reduced pressure to obtain 9.9 parts of polymer. The polymer has the following structural units.
Weight average molecular weight 1.9 × 10 ⁴ , Mw / Mn 2.0,
Molar ratio (I-61) :( IV-1) :( III-61) :( a3-2-1) = 35: 40: 10: 15

Polymer (2): Synthesis of (D10) 4.8 parts of 1,4-dioxane was charged into a four-necked flask equipped with a condenser, a stirrer, and a thermometer, and kept at 72 ° C. 4.43 parts of the compound represented by formula (I-61), 6.00 parts of the compound represented by formula (IV-1), 5.82 parts of the compound represented by formula (a1-1-1), 0.13 part of 2,2′-azobis (isobutyronitrile) and 0.59 part of 2,2′-azobis (2,4-dimethylvaleronitrile) were dissolved in 24.37 parts of 1,4-dioxane. A solution was obtained. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed liquid was put into 422 parts of n-heptane. The precipitated polymer was dried at 40 ° C. under reduced pressure to obtain 7.7 parts of a polymer. The polymer has the following structural units.
Weight average molecular weight 8.6 × 10 ³ , Mw / Mn 1.5,
Molar ratio (I-61) :( IV-1) :( a1-1-1) = 36: 26: 38

Polymer (2): Synthesis of (D11) In a four-necked flask equipped with a condenser, a stirrer, and a thermometer, 3.1 parts of 1,4-dioxane was charged and kept at 72 ° C. 2.4 parts of the compound represented by formula (I-61), 6.00 parts of the compound represented by formula (IV-1), 1.35 parts of the compound represented by formula (V-1), III-61) compound 0.60 parts, 2,2'-azobis (isobutyronitrile) 0.06 parts and 2,2'-azobis (2,4-dimethylvaleronitrile) 0.26 parts Was dissolved in 12.42 parts of 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed liquid was put into 269 parts of n-heptane. The precipitated polymer was dried under reduced pressure at 40 ° C. to obtain 8.7 parts of a polymer. The polymer has the following structural units.
Weight average molecular weight 1.7 × 10 ⁴ , Mw / Mn 1.9,
Molar ratio (I-61) :( IV-1) :( V-1) :( III-61) = 30: 40: 20: 10

Polymer (2): Synthesis of (D12) 4.54 parts of 1,4-dioxane was charged into a four-necked flask equipped with a condenser, a stirrer, and a thermometer, and kept at 72 ° C. 7.61 parts of the compound represented by formula (I-63) 3.70 parts of the compound represented by formula (VII-1), 3.82 parts of the compound represented by formula (a1-1-1), 2 , 2′-azobis (isobutyronitrile) 0.11 part and 2,2′-azobis (2,4-dimethylvaleronitrile) 0.48 part are dissolved in 18.16 parts of 1,4-dioxane and dissolved. A liquid was obtained. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed liquid was put into 393 parts of n-heptane. The precipitated polymer was dried under reduced pressure at 40 ° C. to obtain 10.4 parts of the polymer. The polymer has the following structural units.
Weight average molecular weight 7.1 × 10 ³ , Mw / Mn 1.5,
Molar ratio (I-63) :( VII-1) :( a1-1-1) = 45: 30: 25

Polymer (2): Synthesis of (D13) A 4-necked flask equipped with a condenser, a stirrer, and a thermometer was charged with 4.57 parts of 1,4-dioxane and kept at 72 ° C. 2.42 parts of the compound represented by formula (I-61), 2.61 parts of the compound represented by formula (V-1), 6.00 parts of the compound represented by formula (VII-1), 4.21 parts of a compound represented by a1-1-1), 0.12 part of 2,2′-azobis (isobutyronitrile) and 2,2′-azobis (2,4-dimethylvaleronitrile). 56 parts were dissolved in 18.29 parts of 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed liquid was put into 396 parts of n-heptane. The precipitated polymer was dried at 40 ° C. under reduced pressure to obtain 9.8 parts of a polymer. The polymer has the following structural units.
Weight average molecular weight 1.0 × 10 ⁴ , Mw / Mn 1.5,
Molar ratio (I-61) :( V-1) :( VII-1) :( a1-1-1) = 14: 18: 36: 32

Polymer (2): Synthesis of (D14) Synthesis of polymer (D2) except that the compound represented by formula (a3-1-1) is used instead of the compound represented by formula (III-61) (D14) is obtained in the same manner as in the example. The polymer has the following structural units.
Molar ratio (I-61) :( a3-1-1) = 36: 64

Polymer (2): Synthesis of (D15) Polymer (D12) except that the compound represented by formula (a1-1-2) is used in place of the compound represented by formula (a1-1-1). (D15) is obtained in the same manner as in the above synthesis example. The polymer has the following structural units.
Molar ratio (I-63) :( VII-1) :( a1-1-2) = 45: 30: 25

Polymer (2): Synthesis of (D16) In place of the compound represented by the formula (a1-1-1), the polymer (D12) is used except that the compound represented by the formula (a1-2-1) is used. (D16) is obtained in the same manner as in the above synthesis example. The polymer has the following structural units.
Molar ratio (I-63) :( VII-1) :( a1-2-1) = 45: 30: 25

Polymer (2): Synthesis of (D17) A 4-necked flask equipped with a condenser, a stirrer, and a thermometer was charged with 4.21 parts of 1,4-dioxane and kept at 72 ° C. 10.53 parts of the compound represented by formula (I-63) 3.50 parts of the compound represented by formula (VII-1), 14.05 parts of the compound represented by formula (a1-1-1), 2 , 2'-azobis (isobutyronitrile) 0.17 parts and 2,2'-azobis (2,4-dimethylvaleronitrile) 0.78 parts dissolved in 1,4-dioxane 42.1 parts A liquid was obtained. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed liquid was put into 365 parts of n-heptane. The precipitated polymer was dried at 40 ° C. under reduced pressure to obtain 6.8 parts of polymer. The polymer has the following structural units.
Weight average molecular weight 6.5 × 10 ³ , Mw / Mn 1.4,
Molar ratio (I-63) :( VII-1) :( a1-1-1) = 34: 16: 50

Polymer (2): Synthesis of (D18) A 4-necked flask equipped with a condenser, a stirrer, and a thermometer was charged with 5.48 parts of 1,4-dioxane and kept at 72 ° C. 9.36 parts of the compound represented by the formula (I-63) 3.00 parts of the compound represented by the formula (VII-1), 5.91 parts of the compound represented by the formula (a1-2-1), 2 , 2′-azobis (isobutyronitrile) 0.14 parts and 2,2′-azobis (2,4-dimethylvaleronitrile) 0.63 parts are dissolved in 1,4-dioxane 21.92 parts and dissolved. A liquid was obtained. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained liquid mixture was thrown into 475 parts of n-heptane. The precipitated polymer was dried under reduced pressure at 40 ° C. to obtain 12.6 parts of the polymer. The polymer has the following structural units.
Weight average molecular weight 7.2 × 10 ³ , Mw / Mn 1.4,
Molar ratio (I-63) :( VII-1) :( a1-2-1) = 35: 15: 50

Polymer (2): Synthesis of (D19) A 4-necked flask equipped with a condenser, a stirrer, and a thermometer was charged with 8.29 parts of 1,4-dioxane and kept at 72 ° C. 9.32 parts of the compound represented by the formula (III-63), 4.50 parts of the compound represented by the formula (I-133), 0.10 parts of 2,2′-azobis (isobutyronitrile) and 2 , 2′-azobis (2,4-dimethylvaleronitrile) 0.45 part was dissolved in 12.4-parts 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 72 ° C. over 2 hours. After completion of dropping, the mixture was stirred for 5 hours while being kept at 72 ° C. The obtained mixed liquid was put into 393 parts of n-heptane. The precipitated polymer was dried under reduced pressure at 40 ° C. to obtain 11.4 parts of polymer. The polymer has the following structural units.
Weight average molecular weight 2.4 × 10 ⁴ , Mw / Mn 2.5,
Molar ratio (III-63) :( I-133) = 65: 35

Polymer (2): Synthesis of (H1) A 4-necked flask equipped with a condenser, a stirrer, and a thermometer was charged with 7.4 parts of 1,4-dioxane and kept at 77 ° C. 4.5 parts of a monomer represented by formula (VIII-1), 4.1 parts of a monomer represented by formula (a1-2-1), 0.05 part of 2,2′-azobis (isobutyronitrile) Then, 0.22 part of 2,2′-azobis (2,4-dimethylvaleronitrile) was dissolved in 4.6 parts of 1,4-dioxane to obtain a solution. The obtained solution was dropped into 1,4-dioxane kept at 77 ° C. over 2 hours. The resulting solution was kept at 77 ° C. and kept warm for 5 hours. The solution was cooled to room temperature, poured into a mixed solution of 21.5 parts of water and 85.9 parts of methanol, and the precipitated resin was filtered off. The obtained resin was washed with methanol and then dried under reduced pressure to obtain a polymer (H1). The polymer has the following structural units. In the obtained polymer (H1), the weight average molecular weight (Mw) is 6,800, the dispersity (Mw / Mn) is 1.7, and the molar ratio (VIII-1): (a1-2-1) ) = 70: 30.

Synthesis of Resin (A1) 72.77 parts of 1,4-dioxane was added to a four-necked flask equipped with a thermometer and a reflux tube, bubbled with nitrogen gas for 30 minutes, and the temperature was adjusted to 75 ° C. under a nitrogen seal. . There, 76.30 parts of monomer represented by formula (a1-1-1), 11.42 parts of monomer represented by formula (a1-2-1), and represented by formula (a2-1-1) 11.74 parts of monomer, 52.16 parts of monomer represented by formula (a3-2-1), 0.96 parts of azobisisobutyronitrile, 4.33 parts of azobis-2,4-dimethylvaleronitrile, And the solution which mixed 109.16 parts of 1, 4- dioxane was dripped over 2 hours. After completion of dropping, the reaction mixture was kept at 75 ° C. and stirred for 5 hours. The reaction mixture was cooled to room temperature and 212.26 parts of 1,4-dioxane was added. The reaction mixture was added to a mixed solvent of 536 parts of methanol and 394 parts of water, and the precipitate was collected by filtration. An operation of pouring the filtrate into 985 parts of methanol and precipitating was performed three times for purification, followed by drying under reduced pressure to obtain 112 parts of resin (A1). The resin has the following structural units.
The synthetic data of resin (A1) is shown below. The composition ratio of the obtained resin (A1) is the molar ratio of structural units derived from the respective monomers calculated by measuring the amount of unreacted monomers in the reaction mixture using liquid chromatography (LC 2010HT; manufactured by Shimadzu Corporation). It is.

Composition ratio (a1-1-1): (a1-2-1): (a2-1-1): (a3-2-1) = 40: 10: 10: 40 (molar ratio)
・ Yield: 74%
Mw: 7400, Mw / Mn: 1.83

Examples and Comparative Examples (1) Preparation of resist composition A resist composition was prepared by filtering a mixture obtained by mixing and dissolving the following components through a fluororesin filter having a pore size of 0.2 µm. did.

<Acid generator>
Acid generator B1

<Basic compound: Quencher>
Basic compound C1: 2,6-diisopropylaniline <Solvent 1>
Propylene glycol monomethyl ether acetate 250.0 parts 2-heptanone 20.0 parts Propylene glycol monomethyl ether 10.0 parts γ-butyrolactone 3.5 parts

(2) Evaluation of mask error enhancement factor (MEEF) A composition for organic antireflection film (ARC-29SR; manufactured by Nissan Chemical Industries, Ltd.) was applied to a silicon wafer and baked at 205 ° C. for 60 seconds to obtain a thickness. An organic antireflection film having a thickness of 93 nm was formed. Next, the resist composition was spin-coated thereon so that the film thickness after pre-baking was 100 nm. The obtained resist film was pre-baked for 60 seconds at the temperature described in the “PB” column of the table using a direct hot plate. The resist film after pre-baking was exposed using an ArF excimer stepper (“XT: 1900 Gi” manufactured by ASML Co., Ltd.) and changing the exposure amount stepwise through a photomask.

The illumination conditions of the exposure machine were NA = 1.35, 3/4 Annual, σOUTER = 0.9, and σINNER = 0.675.
As the photomask, a mask for forming a contact hole pattern with a pitch of 100 nm and a hole diameter of 68 to 72 nm (every 1 nm) was used.
Hereinafter, a mask for forming a hole pattern with a hole size of 70 nm is referred to as a “mask with a mask size of 70 nm”, and a pattern formed using the “mask with a mask size of 70 nm” is referred to as a “pattern with a mask size of 70 nm”. .

After exposure, post-exposure baking was performed for 60 seconds at the temperature indicated in the “PEB” column of the table, and paddle development was further performed for 60 seconds with a 2.38% tetramethylammonium hydroxide aqueous solution to obtain a resist pattern. .
With respect to the obtained resist pattern, a pattern having a pitch of 100 nm and a mask size of 68 to 72 nm (every 1 nm) was formed at an exposure amount at which the hole diameter of the pattern having a mask size of 70 nm was 70 nm. Were measured with a scanning electron microscope, and the amount of change in the hole diameter (nm) of the pattern per 1 nm of the mask size was determined as MEEF.
The case where the value of MEEF was less than 3.40 was marked as ◯, and the case where it exceeded 3.40 was marked as x. In Table 24, numerical values in parentheses represent actual measured values of MEEF.

  A resist composition was prepared in the same manner as in Example 1 except that the polymers (D14), (D15) and (D16) were used in place of the polymer (D1), and the MEEF was evaluated. 1 can be obtained.

  According to the resist composition of the present invention, a pattern having an excellent mask error enhancement factor (MEEF) can be obtained.

Claims (1)

One or more polymers selected from the group consisting of polymer (1) and polymer (2), an acid-labile group and insoluble or sparingly soluble in an alkaline aqueous solution; A resist composition comprising a resin that can be dissolved in an aqueous solution and an acid generator.
Polymer (1): A polymer comprising structural units derived from the monomer represented by formula (I).
Polymer (2): a structural unit derived from the monomer represented by formula (I), a structural unit derived from the monomer represented by formula (II), and a structure derived from the monomer represented by formula (III) A polymer comprising one or more structural units selected from the group consisting of units.

[In Formula (I), R ¹ represents a hydrogen atom or a methyl group.
R ² and R ³ each independently represent a hydrocarbon group having 1 to 20 carbon atoms, R ² and R ³ may be bonded to each other to form a ring, and a hydrogen atom contained in the hydrocarbon group May be substituted with a halogen atom, a nitro group, a hydroxy group or a cyano group, and —CH ₂ — contained in the hydrocarbon group is —O—, —CO—, —SO ₂ — or —NH—. ═CH— contained in the hydrocarbon group may be replaced with ═N—.
A ¹ represents a single bond or a divalent linking group. ]

[In the formula (II), R ⁴ represents a hydrogen atom or a methyl group.
R ⁵ represents a C 1-30 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —O—, —CO—, —SO _2. -Or -NH- may be substituted. ]

[In the formula (III), R ⁶ represents a hydrogen atom or a methyl group.
R ⁷ and R ⁸ each independently represent a hydrocarbon group having 1 to 20 carbon atoms, and R ⁷ and R ⁸ may be bonded to each other to form a ring, and a hydrogen atom contained in the hydrocarbon group May be substituted with a halogen atom, a nitro group, a hydroxy group or a cyano group, and —CH ₂ — contained in the hydrocarbon group is —O—, —CO—, —SO ₂ — or —NH—. ═CH— contained in the hydrocarbon group may be replaced with ═N—.
A ² represents a single bond or — (CH ₂ ) _{m ′} —CO—O— ^* .
m ′ represents an integer of 1 to 6.
* Represents a bond with N. ]