JP2011085814A - Resist composition and pattern forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resist composition which shows high resolution, good configuration, a depth of focus (DOF), a good mask error factor (MEF) and good CD uniformity (CDU). <P>SOLUTION: The resist composition comprises a resin comprising repeating units derived from compounds represented by formulae (I) and (II), wherein R<SP>1</SP>and R<SP>3</SP>represent H, halogen-substituted alkyl or the like; T represents an alicyclic hydrocarbon group which may be substituted by halogen, hydroxyl, alkyl, alkoxy or the like, provided that -CH<SB>2</SB>- contained in the group is replaced with one -SO<SB>2</SB>- and may further be displaced by -CO-, -O- or the like; Z<SP>1</SP>represents a saturated hydrocarbon group which may have a substituent, provided that -CH<SB>2</SB>- contained in the group may be replaced with -CO-, -O- or the like; R<SP>4</SP>and R<SP>5</SP>represent H, methyl or the like; and R<SP>6</SP>represents 1-6C alkyl or the like. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a resist composition and a pattern forming method. More specifically, the present invention relates to a resist composition used for fine processing of semiconductors, manufacture of circuit boards such as liquid crystals and thermal heads, and other photofabrication processes. The present invention relates to the pattern forming method used.

  In semiconductor microfabrication, it is desirable to form a pattern with high resolution. As a resist composition, high resolution, good shape, good line edge roughness, wide focus margin (DOF), and mask error factor (MEF) ) Is required.

Recently, monomer G, monomer A, and monomer J are charged in a molar ratio of 42.6: 41.4: 16.0 and polymerized, an acid generator composed of A2, and tri-n-pentylamine. A resist composition comprising a quencher comprising a solvent and a solvent has been proposed (for example, Patent Document 1: Japanese Patent Application Laid-Open No. 2009-62491).

JP 2009-62491 A

  However, higher resolution, better shape, better line edge roughness (LER), better pattern collapse resistance, wider DOF, better mask error factor (MEF) and better CD uniformity than these resist compositions Sex (CDU) is eagerly desired.

  An object of the present invention is to provide a resist composition that exhibits high resolution, good shape, good focus margin (DOF), good mask error factor (MEF), and good CD uniformity (CDU).

［式（Ｉ）中、
Ｒ^１は、水素原子、ハロゲン原子又はハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。
Ｔは、炭素数４〜３６の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれる水素原子は、ハロゲン原子、水酸基、ハロゲン原子又は水酸基で置換されていてもよい炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基、炭素数２〜４のアシル基、炭素数１〜１２のアルコキシカルボニル基、炭素数１〜１２のアルカノイルオキシアルキル基又はシアノ基で置換されていてもよく、該脂環式炭化水素基に含まれる−ＣＨ_２−は、少なくとも１つの−ＳＯ_２−で置き換わっており、さらに、−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^２）−で置き換わっていてもよい。
Ｒ^２は、水素原子又は炭素数１〜６のアルキル基を表す。］

［式（ＩＩ）中、
Ｒ^３は、水素原子、ハロゲン原子又はハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。
Ｚ^１は、置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は、−ＣＯ−、−Ｏ−、−Ｓ−又は−Ｎ（Ｒ^２）−で置き換わっていてもよい。
Ｒ^４及びＲ^５は、それぞれ独立に、水素原子、メチル基又は水酸基を表す。ただし、Ｒ^４及びＲ^５の少なくともいずれか一方は、水酸基を表す。
Ｒ^６は、炭素数１〜６のアルキル基を表す。
Ｒ^２は、水素原子又は炭素数１〜６のアルキル基を表す。
ｎは、０〜１０の整数を表す。］ The resist composition of the present invention comprises a resin having a repeating unit derived from a compound represented by formula (I) and a repeating unit derived from a compound represented by formula (II).

[In the formula (I),
R ¹ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
T represents an alicyclic hydrocarbon group having 4 to 36 carbon atoms, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, a hydroxyl group, a halogen atom or a hydroxyl group. An alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an acyl group having 2 to 4 carbon atoms, and 1 carbon atom 12 alkoxycarbonyl group, may be substituted with alkanoyloxy group or a cyano group having 1 to 12 carbon atoms, -CH 2 contained in the alicyclic hydrocarbon group _- at least one -SO ₂ It may be replaced by —CO—, —O—, —S—, —SO ₂ — or —N (R ² ) —.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. ]

[In the formula (II),
R ³ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
Z ¹ represents a C 1-17 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —CO—, —O—, —S. - or -N ^{(R 2)} - it may be replaced by.
R ⁴ and R ⁵ each independently represents a hydrogen atom, a methyl group or a hydroxyl group. However, at least one of R ⁴ and R ⁵ represents a hydroxyl group.
R ⁶ represents an alkyl group having 1 to 6 carbon atoms.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
n represents an integer of 0 to 10. ]

［式（Ｔ１）中、
環に含まれる水素原子は、ハロゲン原子、水酸基、ハロゲン原子又は水酸基で置換されていてもよい炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基、炭素数２〜４のアシル基、炭素数１〜１２のアルコキシカルボニル基、炭素数１〜１２のアルカノイルオキシアルキル基又はシアノ基で置換されていてもよく、環に含まれる−ＣＨ_２−は、少なくとも１つの−ＳＯ_２−で置き換わっており、さらに、−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^２）−で置き換わっていてもよい。
Ｒ^２は、水素原子又は炭素数１〜６のアルキル基を表す。
＊は−Ｏ−との結合手を表す。
Ｔ^１は、−Ｏ−、−ＮＨ−又は−ＣＨ_２−を表す。］ Such a resist composition preferably has one or more of the following constituent requirements.
T is a group represented by the formula (T1).

[In the formula (T1),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom or a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms. , An aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an acyl group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 1 to 12 carbon atoms, an alkanoyloxyalkyl group having 1 to 12 carbon atoms, or a cyano group. The —CH ₂ — contained in the ring may be replaced with at least one —SO ₂ —, and further —CO—, —O—, —S—, —SO ₂ — or —N (R ² )-May be replaced.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
* Represents a bond with -O-.
T ¹ represents —O—, —NH— or —CH ₂ —. ]

［式（Ｔ２）中、
環に含まれる水素原子は、ハロゲン原子、水酸基、ハロゲン原子又は水酸基で置換されていてもよい炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基、炭素数２〜４のアシル基、炭素数１〜１２のアルコキシカルボニル基、炭素数１〜１２のアルカノイルオキシアルキル基又はシアノ基で置換されていてもよく、環に含まれる−ＣＨ_２−は、−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^２）−で置き換わっていてもよい。
Ｒ^２は、水素原子又は炭素数１〜６のアルキル基を表す。
＊は−Ｏ−との結合手を表す。］ T is a group represented by the formula (T2).

[In the formula (T2),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom or a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms. , An aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an acyl group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 1 to 12 carbon atoms, an alkanoyloxyalkyl group having 1 to 12 carbon atoms, or a cyano group. The —CH ₂ — contained in the ring may be replaced by —CO—, —O—, —S—, —SO ₂ — or —N (R ² ) —.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
* Represents a bond with -O-. ]

  The resin further has an acid labile group and is insoluble or hardly soluble in an alkaline aqueous solution, and the resin that has reacted with an acid is a resin that can be dissolved in an alkaline aqueous solution.

［式（ＩＩＩ）中、
Ｑ^１及びＱ^２は、互いに独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｘ^１は、単結合又は置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｙ^１は、直鎖状又は分岐状の炭素数１〜３６の脂肪族炭化水素基、炭素数３〜３６の脂環式炭化水素基あるいは炭素数６〜３６の芳香族炭化水素基を表し、該脂肪族炭化水素基、脂環式炭化水素基及び芳香族炭化水素基は、置換基を有していてもよい。該脂肪族炭化水素基、脂環式炭化水素基及び芳香族炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｚ^＋は、有機対カチオンを表す。］ Furthermore, an acid generator is included.
The acid generator is an acid generator represented by the formula (III).

[In the formula (III),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
X ¹ represents a single bond or a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —O— or —CO—. It may be replaced with.
Y ¹ represents a linear or branched aliphatic hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, The aliphatic hydrocarbon group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a substituent. —CH ₂ — contained in the aliphatic hydrocarbon group, alicyclic hydrocarbon group and aromatic hydrocarbon group may be replaced by —O— or —CO—.
Z ⁺ represents an organic counter cation. ]

X ¹ is * —CO—O— (* represents a bond with —C (Q ¹ ) (Q ² ) —).
Z ⁺ is an arylsulfonium cation.
Furthermore, a basic compound is included.

The method for forming a pattern of the present invention includes:
(1) A step of applying the resist composition on a substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) The method includes a step of developing the heated composition layer using a developing device.

  According to the resist composition of the present invention, resolution, shape, DOF, MEF, and CDU can be further improved in the formation of a fine pattern.

  The resist composition of the present invention includes a resin having a repeating unit derived from the compound represented by formula (I) and a repeating unit derived from the compound represented by formula (II).

［式（Ｉ）中、
Ｒ^１は、水素原子、ハロゲン原子又はハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。
Ｔは、炭素数４〜３６の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれる水素原子は、ハロゲン原子、水酸基、ハロゲン原子又は水酸基で置換されていてもよい炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基、炭素数２〜４のアシル基、炭素数１〜１２のアルコキシカルボニル基、炭素数１〜１２のアルカノイルオキシアルキル基又はシアノ基で置換されていてもよく、該脂環式炭化水素基に含まれる−ＣＨ_２−は、少なくとも１つの−ＳＯ_２−で置き換わっており、さらに、−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^２）−で置き換わっていてもよい。
Ｒ^２は、水素原子又は炭素数１〜６のアルキル基を表す。］ The compound represented by the formula (I) has a sultone structure as shown below.

[In the formula (I),
R ¹ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
T represents an alicyclic hydrocarbon group having 4 to 36 carbon atoms, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, a hydroxyl group, a halogen atom or a hydroxyl group. An alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an acyl group having 2 to 4 carbon atoms, and 1 carbon atom 12 alkoxycarbonyl group, may be substituted with alkanoyloxy group or a cyano group having 1 to 12 carbon atoms, -CH 2 contained in the alicyclic hydrocarbon group _- at least one -SO ₂ It may be replaced by —CO—, —O—, —S—, —SO ₂ — or —N (R ² ) —.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. ]

In the present specification, examples of the halogen atom include fluorine, chlorine, bromine and iodine atoms.
Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, heptyl group, 2 -Ethylhexyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, etc. are mentioned.
Examples of the alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, a norbornyl group, a 1-adamantyl group, and a 2-adamantyl group. And cycloalkyl groups such as isobornyl group.
As an alkoxy group, a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentoxy group, an n-hexoxy group, a heptoxy group, an octoxy group , 2-ethylhexoxy group, nonyloxy group, decyloxy group, undecyloxy group, dodecyloxy group and the like.

Examples of the aryl group include a phenyl group, a naphthyl group, an anthranyl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group; a tolyl group, a xylyl group, a cumenyl group, a mesityl group, and a biphenyl group. , Anthryl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl and the like.
Examples of the aralkyl group include benzyl, phenethyl, phenylpropyl, trityl, naphthylmethyl group, naphthylethyl group, and the like.
Examples of the acyl group include acetyl, propionyl, butyryl and the like.
Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, an n-propioxycarbonyl group, an isopropoxycarbonyl group, an n-butoxycarbonyl group, a sec-butoxycarbonyl group, a tert-butoxycarbonyl group, and an n-pentoxycarbonyl group. , N-hexoxycarbonyl group, heptoxycarbonyl group and the like.
Examples of the alkanoyloxyalkyl group include acetyloxymethyl group, acetyloxyethyl group, acetyloxypropyl group, propionyl, oxymethyl group, propionyl, oxyethyl group, propionyl, oxypropyl group and the like.

  In the present specification, unless otherwise specified, in each chemical structural formula, each of the above-described substituents can be employed while appropriately selecting the number of carbon atoms, and any chemical compound having the same substituent can be used. Similar substituents can be applied to the structural formula. Those which can take any of linear, branched or cyclic are included unless otherwise specified, and in the same group, linear, branched or cyclic partial structures are mixed. May be.

In the compound represented by the formula (I), R ¹ is preferably a hydrogen atom or a methyl group.
T is suitably a group represented by the formula (T0), and in particular, a group represented by the formula (T0a) is suitable.
Moreover, T is preferably a group represented by the formula (T1), and among them, a group represented by the formula (T1a) is preferable.
Further, T is more preferably a group represented by the formula (T2), and more preferably a group represented by the formula (T2a).

［式中、
環に含まれる水素原子は、ハロゲン原子、水酸基、ハロゲン原子又は水酸基で置換されていてもよい炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基、炭素数２〜４のアシル基、炭素数１〜１２のアルコキシカルボニル基、炭素数１〜１２のアルカノイルオキシアルキル基又はシアノ基で置換されていてもよく、環に含まれる−ＣＨ_２−は、少なくとも１つの−ＳＯ_２−で置換されており、さらに、−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^２）−で置き換わっていてもよい。
Ｒ^２は、水素原子又は炭素数１〜６のアルキル基を表す。
＊は、酸素原子との結合手を表す。
Ｔ^１は、−Ｏ−、−ＮＨ−又は−ＣＨ_２−を表す。］
特に、Ｔの環に含まれる置換基は、ハロゲン原子、水酸基、ハロゲン原子又は水酸基で置換されていてもよい炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数２〜４のアシル基、炭素数１〜６のアルコキシカルボニル基、炭素数１〜６のアルカノイルオキシアルキル基又はシアノ基が好ましい。

[Where:
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom or a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms. , An aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an acyl group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 1 to 12 carbon atoms, an alkanoyloxyalkyl group having 1 to 12 carbon atoms, or a cyano group. The —CH ₂ — contained in the ring may be substituted with at least one —SO ₂ —, and further —CO—, —O—, —S—, —SO ₂ — or —N (R ² ) It may be replaced by-.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
* Represents a bond with an oxygen atom.
T ¹ represents —O—, —NH— or —CH ₂ —. ]
In particular, the substituent contained in the ring of T includes a halogen atom, a hydroxyl group, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom or a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, and 2 to 2 carbon atoms. 4 acyl groups, C1-C6 alkoxycarbonyl groups, C1-C6 alkanoyloxyalkyl groups or cyano groups are preferred.

Examples of the compound represented by the formula (I) include the following compounds.

  The compound represented by the formula (I) described above can be produced by a method known in the art.

［式（ＩＩ）中、
Ｒ^３は、水素原子、ハロゲン原子又はハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。
Ｚ^１は、置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は、−ＣＯ−、−Ｏ−、−Ｓ−又は−Ｎ（Ｒ^２）−で置き換わっていてもよい。
Ｒ^４及びＲ^５は、それぞれ独立に、水素原子、メチル基又は水酸基を表す。 Ｒ^６は、炭素数１〜６のアルキル基を表す。
ｎは、０〜１０の整数を表す。］
なお、Ｒ^４及びＲ^５の少なくともいずれか一方は、水酸基であることが好ましい。 The compound represented by the formula (II) has an adamantyl group substituted with at least one hydroxyl group as shown below. Of these, compounds having an adamantyl group substituted with at least two hydroxyl groups are preferred.

[In the formula (II),
R ³ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
Z ¹ represents a C 1-17 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —CO—, —O—, —S. - or -N ^{(R 2)} - it may be replaced by.
R ⁴ and R ⁵ each independently represents a hydrogen atom, a methyl group or a hydroxyl group. R ⁶ represents an alkyl group having 1 to 6 carbon atoms.
n represents an integer of 0 to 10. ]
Note that at least one of R ⁴ and R ⁵ is preferably a hydroxyl group.

［式（Ｚ１）〜式（Ｚ３）中、
Ｚ^Ａ及びＺ^Ｂは、それぞれ独立に、置換基を有していてもよい炭素数１〜６のアルキレン基を表す。ただし、式（Ｘ^１−Ａ）〜式（Ｘ^１−Ｃ）で表される基の炭素数は１〜１７である。］ Examples of the saturated hydrocarbon group include divalent groups including an alkylene group and a cycloalkylene group.
Examples of the alkylene group include a methylene group, a dimethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, a heptamethylene group, an octamethylene group, a nonamethylene group, a decamethylene group, an undecamethylene group, and a dodecamethylene group. , Tridecamethylene group, tetradecamethylene group, pentadecamethylene group, hexadecamethylene group, heptacamethylene group, ethylene group, propylene group, isopropylene group, sec-butylene group and tert-butylene group.
Examples of the divalent group containing a cycloalkylene group include groups represented by formulas (Z1) to (Z3).

[In Formula (Z1)-Formula (Z3),
Z ^A and Z ^B each independently represent an alkylene group having 1 to 6 carbon atoms which may have a substituent. However, the number of carbon atoms of the group represented by the formula ^(X 1 -A) ~ Formula ^(X 1 -C) is 1 to 17. ]

In the compound represented by formula (II), R ³ is preferably a hydrogen atom or a methyl group.
Z ¹ is preferably an alkylene group.
In Z ¹ , a saturated hydrocarbon group, particularly a group in which —CH ₂ — contained in an alkylene group is replaced by —CO—, —O—, —S— or —N (R ⁷ ) — is, for example, —O—. ^{, -O-CO -, - O} -CO-O -, - O-Z 2 -, - O-CO-Z 2 -, - O-CO-O-Z 2 -, - CO-O-Z 2 - ^{CO-O -, - NH-} CO-O -, - NH-Z 2 -, - N (CH 3) -Z 2 -, - N (C 2 H 5) -Z 2 - , and the like. Here, ^{Z 2} is an alkylene group having 1 to 6 carbon atoms. Among them, —O—, —O—CO—, —O—CO—O—, —CO—O—Z ² —CO—O—, —NH—, —N (CH ₃ ) —, —N (C ₂ H ₅₎ - it is preferred.

Examples of the compound represented by the formula (II) include the following compounds.

  Among them, 3,5-dihydroxy-1-adamantyl acrylate or 3,5-dihydroxy-1-adamantyl methacrylate, 1- (3,5-dihydroxy-1-adamantyloxycarbonyl) methyl acrylate or 1- (3,3) methacrylate 5-dihydroxy-1-adamantyloxycarbonyl) methyl and the like are preferable, and 3,5-dihydroxy-1-adamantyl acrylate or 3,5-dihydroxy-1-adamantyl methacrylate is more preferable.

The molar ratio of the content of the repeating unit derived from the compound represented by formula (I) and the repeating unit derived from the compound represented by formula (II) in the resin is usually 1: 0.2 to 1:10. Yes, preferably 1: 0.4 to 1: 8, more preferably 1: 0.5 to 1: 5.
The total content of the repeating unit derived from the compound represented by formula (I) and the repeating unit derived from the compound represented by formula (II) in the resin is usually 5 to 100 mol% in all the units of the resin. Preferably, it is 15-80 mol%, More preferably, it is 20-70 mol%.

  In addition to the repeating unit derived from the monomer represented by the formula (I) and the formula (II), the resin of the present invention further has an acid-labile group and is insoluble or hardly soluble in an alkaline aqueous solution. The resin that has reacted with the acid is preferably a resin that can be dissolved in an alkaline aqueous solution.

Examples of the acid labile group include a group having an alkyl ester in which the carbon atom adjacent to the oxygen atom is a quaternary carbon atom, a group having a carboxylic acid ester such as an alicyclic ester, and a carbon atom adjacent to the oxygen atom. And a group having a lactone ring which is a quaternary carbon atom.
Here, the quaternary carbon atom means a carbon atom bonded to a substituent other than a hydrogen atom and not bonded to hydrogen, and an acid labile group is adjacent to an oxygen atom of an ether bond. It is preferable that the carbon atom to be bonded is a quaternary carbon atom bonded to three carbon atoms.

To illustrate a group having a carboxylic acid ester which is one of the acid labile group as R ester of -COOR, (-. The COO-C (CH ₃₎ referred in ₃ form a tert- butyl ester), tert -Alkyl ester in which the carbon atom adjacent to the oxygen atom represented by butyl ester is a quaternary carbon atom; methoxymethyl ester, ethoxymethyl ester, 1-ethoxyethyl ester, 1-isobutoxyethyl ester, 1-isopropoxyethyl Ester, 1-ethoxypropyl ester, 1- (2-methoxyethoxy) ethyl ester, 1- (2-acetoxyethoxy) ethyl ester, 1- [2- (1-adamantyloxy) ethoxy] ethyl ester, 1- [2 -(1-adamantanecarbonyloxy) ethoxy] ethyl ester Acetal-type esters such as tetrahydro-2-furyl ester and tetrahydro-2-pyranyl ester; isobornyl ester and 1-alkylcycloalkyl ester, 2-alkyl-2-adamantyl ester, 1- (1-adamantyl) -1- Examples thereof include alicyclic esters in which the carbon atom adjacent to the oxygen atom is a quaternary carbon atom, such as an alkylalkyl ester.

  Examples of the group having a carboxylic acid ester include a group having a (meth) acrylic acid ester, a norbornene carboxylic acid ester, a tricyclodecene carboxylic acid ester, and a tetracyclodecene carboxylic acid ester.

The resin of the present invention can be produced by addition polymerization of a monomer having an acid labile group and an olefinic double bond.
Such monomers include bulky groups such as alicyclic structures such as 2-alkyl-2-adamantyl groups and 1- (1-adamantyl) -1-alkylalkyl groups as acid labile groups. Monomers are preferred because the resolution of the resulting resist tends to be excellent.

  Specific examples of the monomer containing a bulky group include 2-alkyl-2-adamantyl (meth) acrylate, 1- (1-adamantyl) -1-alkylalkyl (meth) acrylate, and 5-norbornene-2. -2-alkyl-2-adamantyl carboxylate, 1- (1-adamantyl) -1-alkylalkyl 5-norbornene-2-carboxylate, 2-alkyl-2-adamantyl α-chloroacrylate, α-chloroacrylic acid 1- (1-adamantyl) -1-alkylalkyl and the like.

  In particular, when 2-alkyl-2-adamantyl (meth) acrylate or 2-alkyl-2-adamantyl α-chloroacrylate is used as a monomer, it is preferable because the resolution of the resulting resist tends to be excellent.

  Specifically, as 2-alkyl-2-adamantyl (meth) acrylate, for example, 2-methyl-2-adamantyl acrylate, 2-methyl-2-adamantyl methacrylate, 2-ethyl-2-acrylate Examples thereof include adamantyl, 2-ethyl-2-adamantyl methacrylate, 2-n-butyl-2-adamantyl acrylate, and the like. Examples of α-chloroacrylic acid 2-alkyl-2-adamantyl include α-chloroacrylic acid. Examples include 2-methyl-2-adamantyl and 2-ethyl-2-adamantyl α-chloroacrylate.

  Among these, when 2-ethyl-2-adamantyl (meth) acrylate or 2-isopropyl-2-adamantyl (meth) acrylate is used, the resulting resist tends to have excellent sensitivity and heat resistance. preferable.

  (Meth) acrylic acid 2-alkyl-2-adamantyl can be usually produced by a reaction of 2-alkyl-2-adamantanol or a metal salt thereof with acrylic acid halide or methacrylic acid halide.

［式（ｇ）中、Ｒ¹⁰は、水素原子、ハロゲン原子又はハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。
Ｒ¹¹は、それぞれ独立に、ハロゲン原子、水酸基、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数２〜４のアシル基、炭素数２〜４のアシルオキシ基、アクリロイル基又はメタクリロイル基を表す。
ｌ^ａは０〜４の整数を表す。ｌ^ａが２以上の整数である場合、複数のＲ¹¹は同一の種類の基であっても異なる種類の基であってもよい。
Ｒ¹²及びＲ¹³はそれぞれ独立に、水素原子又は炭素数１〜１２の炭化水素基を表す。
Ｘ^ａ２は、単結合又は置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^ｃ）−で置き換わっていてもよい。
Ｒ^ｃは、水素原子又は炭素数１〜６のアルキル基を表す。
Ｙ^ａ３は、炭素数１〜１２の脂肪族炭化水素基、炭素数３〜１８の飽和環状炭化水素基又は炭素数６〜１８の芳香族炭化水素基であり、該脂肪族炭化水素基、飽和環状炭化水素基及び芳香族炭化水素基は、置換基を有していてもよい。］ Examples of the monomer having an acid labile group other than the above include a monomer (g) having an acetal labile group represented by the formula (g).

[In the formula (g), R ¹⁰ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
R ¹¹ is independently a halogen atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, or acryloyl. Represents a group or a methacryloyl group.
l ^a represents an integer of 0 to 4; If l ^a is an integer of 2 or more, plural R ¹¹ may be the same kind a group even if different types of groups.
R ¹² and R ¹³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.
X ^a2 represents a C1-C17 saturated hydrocarbon group which may have a single bond or a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —CO—, —O—, -S -, - SO ₂ - or -N ^{(R c)} - may be replaced by.
R ^c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
Y ^a3 is an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the aliphatic hydrocarbon group, saturated The cyclic hydrocarbon group and the aromatic hydrocarbon group may have a substituent. ]

Examples of the alkyl group which may have a halogen atom include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, A perfluorohexyl group etc. are mentioned.
Q ¹ and Q ² are each independently preferably a perfluoromethyl group or a fluorine atom, more preferably a fluorine atom.
The alkyl group and the alkoxy group are preferably groups having 1 to 4 carbon atoms, more preferably groups having 1 to 2 carbon atoms, and even more preferably groups having 1 carbon atom.
Examples of the acyloxy group include acetyloxy, propionyloxy, butyryloxy and the like.
Examples of the hydrocarbon group include an aliphatic hydrocarbon, an alicyclic hydrocarbon, an aromatic hydrocarbon, or a group obtained by combining these. Among them, methyl groups, ethyl groups, n-propyl groups, isopropyl groups, n-butyl groups, sec-butyl groups, tert-butyl groups, pentyl groups, hexyl groups, octyl groups, 2-ethylhexyl groups and other alkyl groups, An alicyclic hydrocarbon such as a cyclohexyl group, adamantyl group, 2-alkyl-2-adamantyl group, 1- (1-adamantyl) -1-alkyl group, and isobornyl group is preferred.
The saturated cyclic hydrocarbon group may be monocyclic or polycyclic. The monocyclic saturated cyclic hydrocarbon group includes a cycloalkyl group (for example, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, methylcycloheptyl group). Group, cyclooctyl group, cyclononyl group, cyclodecyl group), cycloalkenyl group (for example, cyclopentenyl group, cyclohexenyl group, cycloheptenyl group, cyclooctenyl group) and the like. Examples of the polycyclic saturated cyclic hydrocarbon group include a group obtained by hydrogenating a condensed aromatic hydrocarbon group (for example, hydronaphthyl group), a bridged cyclic hydrocarbon group (for example, 1-adamantyl group, 2-adamantyl group). Group, norbornyl group, methylnorbornyl, isobornyl group) and the like. The bridged cyclic hydrocarbon group may have an unsaturated bond therein (for example, a norborneneyl group). Further, a bridged ring (for example, norbornane ring) and a monocyclic ring (for example, cycloheptane ring or cyclohexane ring) or a polycyclic ring (for example, decahydronaphthalene ring) or bridged rings are condensed. The group is also included in the saturated cyclic hydrocarbon group.

Examples of the substituent for Y ^a3 include a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, A glycidyloxy group, a C2-C4 acyl group, a cyano group, etc. are mentioned.

Examples of the monomer (g) include the following monomers.

  The content of the repeating unit derived from the monomer having an acid labile group in the resin is usually 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 in all units of the resin. -85 mol%.

  The resin used in the present invention is stable in acid in addition to the repeating unit derived from the compound represented by formula (I) and formula (II) and the repeating unit derived from a monomer having an acid labile group. It may contain a repeating unit derived from a monomer. Here, the structure derived from an acid-stable monomer means a structure that is not cleaved by an acid generator described later.

The content of the repeating unit derived from the monomer having an acid-stable group in the resin is usually from 5 to 90 mol%, preferably from 10 to 85 mol%, more preferably from 15 to 15 mol% in all the units of the resin. 80 mol%.
Specifically, a repeating unit derived from a monomer having a free carboxylic acid group such as acrylic acid or methacrylic acid, a repeating unit derived from an aliphatic unsaturated dicarboxylic anhydride such as maleic anhydride or itaconic anhydride , A repeating unit derived from 2-norbornene, a repeating unit derived from (meth) acrylonitrile, an alkyl ester or 1-adamantyl ester in which the carbon atom adjacent to the oxygen atom is a secondary or tertiary carbon atom (meth) Derived from a repeating unit derived from an acrylate ester, a repeating unit derived from a styrene monomer such as p- or m-hydroxystyrene, and a (meth) acryloyloxy-γ-butyrolactone in which the lactone ring may be substituted with an alkyl group And the like. In the 1-adamantyl ester, the carbon atom adjacent to the oxygen atom is a quaternary carbon atom. However, the 1-adamantyl ester is an acid-stable group, and a hydroxyl group or the like may be bonded to the 1-adamantyl ester.

  Specific acid-stable monomers include 3-hydroxy-1-adamantyl (meth) acrylate, α- (meth) acryloyloxy-γ-butyrolactone, β- (meth) acryloyloxy-γ-butyrolactone, formula (a) A monomer giving a repeating unit represented by formula (b), a monomer giving a repeating unit represented by formula (b), an alicyclic compound having an olefinic double bond in the molecule such as hydroxystyrene or norbornene, and an aliphatic such as maleic anhydride Examples thereof include unsaturated dicarboxylic acid anhydride and itaconic anhydride.

  Among them, in particular, a repeating unit derived from a styrene monomer such as p- or m-hydroxystyrene, a repeating unit derived from a repeating unit derived from 3-hydroxy-1-adamantyl (meth) acrylate, and the formula (a) A resist obtained from a resin containing either a repeating unit represented by formula (b) or a repeating unit represented by formula (b) is preferred because it tends to improve the adhesion to the substrate and the resolution of the resist.

（式中、Ｒ^Ａ及びＲ^Ｂは、互いに独立に、水素原子又はメチル基を表し、Ｒ^Ｃ及びＲ^Ｄは、互いに独立に水素原子、メチル基、トリフルオロメチル基又はハロゲン原子を表し、ｉ及びｊは、１〜３の整数を表す。ｉが２または３のときには、Ｒ^Ｃは互いに異なる基であってもよく、ｊが２または３のときには、Ｒ^Ｄは互いに異なる基であってもよい。）

(Wherein, R ^A and R ^B each independently represent a hydrogen atom or a methyl group, R ^C and R ^D each independently represent a hydrogen atom, a methyl group, a trifluoromethyl group, or a halogen atom; And j represents an integer of 1 to 3. When i is 2 or 3, ^RC may be different from each other, and when j is 2 or 3, ^RD may be different from each other. Good.)

  Monomers such as (meth) acrylic acid 3-hydroxy-1-adamantyl are commercially available, but can also be produced, for example, by reacting the corresponding hydroxyadamantane with (meth) acrylic acid or a halide thereof.

  In addition, a monomer such as (meth) acryloyloxy-γ-butyrolactone is obtained by reacting α- or β-bromo-γ-butyrolactone whose lactone ring may be substituted with an alkyl group with acrylic acid or methacrylic acid, or lactone. It can be produced by reacting an α- or β-hydroxy-γ-butyrolactone whose ring may be substituted with an alkyl group with an acrylic acid halide or a methacrylic acid halide.

  Examples of the monomer that gives the repeating unit represented by the formulas (a) and (b) include (meth) acrylic acid esters of alicyclic lactones having the following hydroxyl groups, and mixtures thereof. These esters can be produced, for example, by a reaction between a corresponding alicyclic lactone having a hydroxyl group and (meth) acrylic acid (see, for example, JP-A No. 2000-26446).

  Here, as (meth) acryloyloxy-γ-butyrolactone, for example, α-acryloyloxy-γ-butyrolactone, α-methacryloyloxy-γ-butyrolactone, α-acryloyloxy-β, β-dimethyl-γ-butyrolactone, α- Methacryloyloxy-β, β-dimethyl-γ-butyrolactone, α-acryloyloxy-α-methyl-γ-butyrolactone, α-methacryloyloxy-α-methyl-γ-butyrolactone, β-acryloyloxy-γ-butyrolactone, β- Examples include methacryloyloxy-γ-butyrolactone, β-methacryloyloxy-α-methyl-γ-butyrolactone, and the like.

  The content of the repeating unit derived from the monomer represented by the formula (a) or (b) in the resin is usually 5 to 50 mol%, preferably 10 to 45 mol% in all units of the resin. More preferably, it is 15-40 mol%.

When KrF excimer laser exposure or EUV exposure is used, sufficient transmittance can be obtained even if a repeating unit derived from a styrene monomer such as p- or m-hydroxystyrene is used as the repeating unit of the resin. Such a copolymer resin can be obtained by radically polymerizing the corresponding (meth) acrylic acid ester monomer, acetoxystyrene, and styrene and then deacetylating with an acid.
As a monomer which gives the repeating unit derived from a styrene-type monomer, the following compounds are mentioned, for example.

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

  The content of the repeating unit derived from the styrenic monomer in the resin is usually from 5 to 90 mol%, preferably from 10 to 85 mol%, more preferably from 15 to 80 mol%, in all units of the resin. .

  Moreover, since the resin containing a repeating unit derived from 2-norbornene has an alicyclic skeleton directly in its main chain, it has a strong structure and exhibits excellent dry etching resistance. A repeating unit derived from 2-norbornene can be introduced into the main chain by radical polymerization using, in addition to the corresponding 2-norbornene, an aliphatic unsaturated dicarboxylic anhydride such as maleic anhydride or itaconic anhydride. . Therefore, the one formed by opening the double bond of the norbornene structure can be represented by the formula (c), and the one formed by opening the double bond of maleic anhydride and itaconic anhydride is respectively It can represent with Formula (d) and Formula (e).

Here, R ^E and R ^F in the formula (c) are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, a carboxyl group, a cyano group, or —COOU (U is an alcohol residue). Or R ^E and R ^F are bonded to each other to represent a carboxylic acid anhydride residue represented by —C (═O) OC (═O) —.
When R ^E and R ^F are a group —COOU, the carboxyl group is an ester group, and the alcohol residue corresponding to U has, for example, about 1 to 8 carbon atoms that may be substituted. And an alkyl group, a 2-oxooxolan-3- or -4-yl group. Here, in the alkyl group, a hydroxyl group, an alicyclic hydrocarbon residue, or the like may be bonded as a substituent.
Specific examples in the case where R ^E and R ^F are alkyl groups include a methyl group, an ethyl group, a propyl group, and the like. Specific examples of the alkyl group to which a hydroxyl group is bonded include a hydroxymethyl group and 2-hydroxyethyl group. Groups and the like.

Thus, specific examples of the norbornene structure represented by the formula (c), which is a monomer that gives a stable repeating unit to an acid, include the following compounds.
2-norbornene,
2-hydroxy-5-norbornene,
5-norbornene-2-carboxylic acid,
Methyl 5-norbornene-2-carboxylate,
2-hydroxy-1-ethyl 5-norbornene-2-carboxylate,
5-norbornene-2-methanol,
5-norbornene-2,3-dicarboxylic anhydride.

In addition, if U of —COOU of R ^E and R ^F in formula (c) is an acid-labile group such as an alicyclic ester in which the carbon atom adjacent to the oxygen atom is a quaternary carbon atom, Even though it has a norbornene structure, it is a repeating unit having an acid labile group. Examples of the monomer containing a norbornene structure and an acid labile group include, for example, 5-norbornene-2-carboxylic acid-t-butyl, 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, and 5-norbornene. 2-carboxylate 1-methylcyclohexyl, 5-norbornene-2-carboxylic acid 2-methyl-2-adamantyl, 5-norbornene-2-carboxylic acid 2-ethyl-2-adamantyl, 5-norbornene-2-carboxylic acid 1- (4-methylcyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1- (4-hydroxycyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1-methyl-1- (4-Oxocyclohexyl) ethyl, 5-norbornene-2-carboxylic acid 1- (1-adama) Chill) -1-methylethyl and the like.

  The content of the repeating unit represented by the formula (c), (d) or (e) in the resin is usually 2 to 40 mol%, preferably 3 to 30 mol%, in all units of the resin. More preferably, it is 5-20 mol%.

  Further, the acid-stable group may contain a repeating unit represented by the formula (f) and a repeating unit containing a fluorine atom.

［式（ｆ）中、
Ｒ^Ｇは、水素原子、メチル基又はトリフルオロメチル基を表す。
ＡＲは、炭素数１〜３０の直鎖状、分岐状又は環状の炭化水素基を表し、該炭化水素基に含まれる水素原子の少なくとも１個以上がフッ素原子に置換されている。該炭化水素基に含まれるメチレン基は、酸素原子、硫黄原子又は−Ｎ（Ｒ^２）−で置換されていてもよく、該炭化水素基に含まれる水素原子は、水酸基あるいは直鎖状又は分岐状の炭素数１〜６の脂肪族炭化水素基で置換されていてもよい。］

[In the formula (f),
R ^G represents a hydrogen atom, a methyl group or a trifluoromethyl group.
AR represents a linear, branched or cyclic hydrocarbon group having 1 to 30 carbon atoms, and at least one hydrogen atom contained in the hydrocarbon group is substituted with a fluorine atom. The methylene group contained in the hydrocarbon group may be substituted with an oxygen atom, a sulfur atom or —N (R ² ) —, and the hydrogen atom contained in the hydrocarbon group may be a hydroxyl group, a straight chain or a branched chain. It may be substituted with an aliphatic hydrocarbon group having 1 to 6 carbon atoms. ]

  Specific examples of the monomer that gives the repeating unit represented by the formula (f) include the following monomers.

  The content of the repeating unit represented by the formula (f) in the resin is usually 1 to 30 mol%, preferably 2 to 20 mol%, more preferably 3 to 10 mol% in all units of the resin. It is.

  And as a repeating unit derived from a monomer having an acid labile group, in particular, 2-alkyl-2-adamantyl methacrylate, 2-alkyl-2-adamantyl acrylate 1- (1-adamantyl) -1 -When alkyl-alkyl, repeating unit derived from 2-alkyl-2-adamantyl methacrylate 1- (1-adamantyl) -1-alkylalkyl acrylate is included, the repeating unit comprises all repeating units constituting the resin. When the content is 15 mol% or more, the resin has an alicyclic group and thus has a sturdy structure, which is advantageous in terms of dry etching resistance of the resist to be provided.

In addition, when using an alicyclic compound having an olefinic double bond in the molecule and an aliphatic unsaturated dicarboxylic acid anhydride as monomers, these tend to be difficult to undergo addition polymerization. These are preferably used in excess.

Further, as the monomer used, monomers having the same olefinic double bond but different acid labile groups may be used in combination, or monomers having the same acid labile group but different olefinic double bonds may be used. You may use together, You may use together the monomer from which the combination of an acid labile group and an olefinic double bond differs.

  The weight average molecular weight of the resin is preferably 2,500 or more and 100,000 or less, more preferably 2,700 or more and 50,000 or less, and still more preferably 3,000 or more and 40,000 or less.

The resist composition of the present invention contains an acid generator.
As an acid generator, photo-initiator of photocation polymerization, photo-initiator of photo-radical polymerization, photo-decoloring agent of dyes, photo-discoloring agent, or irradiation with actinic ray or radiation used for micro-resist etc. Known compounds that generate acids and mixtures thereof can be appropriately selected and used.

  Examples include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.

  Examples of compounds in which a group or a compound that generates an acid upon irradiation with actinic rays or radiation is introduced into the main chain or side chain of the polymer include, for example, US Pat. No. 3,849,137 and German Patent No. 3914407. JP, 63-26653, JP, 55-164824, JP, 62-69263, JP, 63-146038, JP, 63-163452, JP, 62-153853, The compounds described in Japanese Utility Model Laid-Open No. 63-146029 can be used.

  Furthermore, compounds capable of generating an acid by light described in US Pat. No. 3,779,778, European Patent 126,712 and the like can also be used.

［式（ＩＩＩ）中、
Ｑ^１及びＱ^２は、互いに独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｘ^１は、単結合又は置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｙ^１は、直鎖状又は分岐状の炭素数１〜３６の脂肪族炭化水素基、炭素数３〜３６の脂環式炭化水素基あるいは炭素数６〜３６の芳香族炭化水素基であり、該脂肪族炭化水素基、脂環式炭化水素基及び芳香族炭化水素基は、置換基を有していてもよく、該脂肪族炭化水素基及び脂環式炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｚ^＋は、有機カチオンを表す。］ It does not specifically limit as an acid generator, A well-known acid generator can be used in the said field | area. For example, the acid generator which uses the salt represented by Formula (III) as an active ingredient is mentioned.

[In the formula (III),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
X ¹ represents a single bond or a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —O— or —CO—. It may be replaced with.
Y ¹ is a linear or branched aliphatic hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, The aliphatic hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group may have a substituent, and —CH ₂ contained in the aliphatic hydrocarbon group and alicyclic hydrocarbon group. -May be replaced by -O- or -CO-.
Z ⁺ represents an organic cation. ]

  Examples of perfluoroalkyl groups include perfluoromethyl group, perfluoroethyl group, perfluoro-n-propyl group, perfluoroisopropyl group, perfluoro-n-butyl group, perfluoro-sec-butyl group, perfluoro-tert-butyl group, perfluoro-n- A pentyl group, a perfluoro-n-hexyl group, etc. are mentioned. Of these, a perfluoromethyl group is preferable.

［式（Ｘ^１−Ａ）〜式（Ｘ^１−Ｃ）中、
Ｘ^Ａ及びＸ^Ｂは、それぞれ独立に、置換基を有していてもよい炭素数１〜６のアルキレン基を表す。ただし、式（Ｘ^１−Ａ）〜式（Ｘ^１−Ｃ）で表される基の炭素数は１〜１７である。］ Examples of the saturated hydrocarbon group include divalent groups including an alkylene group and a cycloalkylene group.
Examples of the divalent group containing a cycloalkylene group include groups represented by the formula (X ¹ -A) to the formula (X ¹ -C).

[In the formula (X ¹ -A) to formula (X ¹ -C),
X ^A and X ^B each independently represent a ^C 1-6 alkylene group which may have a substituent. However, the number of carbon atoms of the group represented by the formula ^(X 1 -A) ~ Formula ^(X 1 -C) is 1 to 17. ]

Examples of the group in which —CH ₂ — contained in the saturated hydrocarbon group is substituted with —O— or —CO— include, for example, —X ¹⁰ —O—, —X ¹⁰ —CO—O—, and —X ¹⁰ —O. —CO—, —X ¹⁰ —O—X ¹¹ — and the like can be mentioned. Preferably _{-CO-O- [CH 2] h} - (h is an integer of 0) can be mentioned.
Here, X ¹⁰ and X ¹¹ each independently represent a single bond, a linear or branched alkylene group having 1 to 15 carbon atoms. However, in the group in which the methylene group contained in the alkylene group is substituted, the number of atoms constituting the main chain of each of the above groups is 1 to 17, which is the same as k.

Examples of the substituent that Y ¹ may have include, for example, a halogen atom, a hydroxyl group, a cyano group, an oxo group, a glycidyloxy group, an acyl group having 2 to 4 carbon atoms, a linear or branched carbon number of 1 -6 alkoxy group, C1-C7 alkoxycarbonyl group, linear or branched C1-C12 aliphatic hydrocarbon group, C3-C10 alicyclic hydrocarbon group, carbon Examples thereof include hydrocarbon groups such as an aromatic hydrocarbon group having 6 to 20 carbon atoms and an aralkyl group having 7 to 21 carbon atoms.

In the salt represented by the formula (III), Q ¹ and Q ² are preferably each independently a fluorine atom or CF ₃ , and both are more preferably a fluorine atom.

なかでも、Ｘ^１は、＊−ＣＯ−Ｏ（＊は、−Ｃ（Ｑ^１）（Ｑ^２）−との結合手を表す）であることが好ましい。 For example, specific examples of X ¹ include the following groups.

Among these, X ¹ is preferably * —CO—O (* represents a bond with —C (Q ¹ ) (Q ² ) —).

Y ¹ is suitably an alicyclic hydrocarbon group having 4 to 36 carbon atoms which may have a substituent.
Examples of the substituent that may be substituted with the aliphatic hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group of Y ¹ include, for example, a halogen atom (excluding a fluorine atom), a hydroxyl group, and a straight chain Or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms, aromatic hydrocarbon group having 6 to 20 carbon atoms, aralkyl group having 7 to 21 carbon atoms, glycidyloxy group And one or more selected from the group consisting of acyl groups having 2 to 4 carbon atoms.

  Examples of the anion of the salt represented by the formula (III) include the following formula (IIIA), formula (IIIB), formula (IIIC), formula (IIID) and the like. Of these, anions represented by formula (IIIA) and formula (IIIB) are suitable.

［式（ＩＩＩＡ）、式（ＩＩＩＢ）、式（ＩＩＩＣ）及び式（ＩＩＩＤ）中、
Ｑ^１、Ｑ^２、Ｙ^１、Ｘ¹⁰及びＸ¹¹は、式（ＩＩＩ）における定義と同じである。］

[In Formula (IIIA), Formula (IIIB), Formula (IIIC) and Formula (IIID),
Q ¹ , Q ² , Y ¹ , X ¹⁰ and X ¹¹ are the same as defined in formula (III). ]

［式（Ｙ０）中、
環Ｗ’は、炭素数３〜３６の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。
Ｒ^ｂは、互いに独立に、ハロゲン原子、水酸基、直鎖状又は分岐状の炭素数１〜１２の脂肪族炭化水素基、炭素数６〜２０の芳香族炭化水素基、炭素数７〜２１のアラルキル基、炭素数１〜１２のアルコキシ基、グリシジルオキシ基あるいは炭素数２〜４のアシル基を表す。
ｘは、０〜８の整数を表す。ｘが２以上の場合、複数のＲ^ｂは、同一でも異なってもよい。
Ｒ^ａは、水素原子あるいは直鎖状又は分岐状の炭素数１〜６の炭化水素基を表すか、環Ｗ’に含まれる炭素原子と互いに結合して環を形成していてもよい。］ Y ¹ is preferably a group represented by the formula (Y0).

[In the formula (Y0),
Ring W ′ represents an alicyclic hydrocarbon group having 3 to 36 carbon atoms, and the methylene group contained in the alicyclic hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.
R ^b is independently of each other a halogen atom, a hydroxyl group, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, or 7 to 21 carbon atoms. An aralkyl group, an alkoxy group having 1 to 12 carbon atoms, a glycidyloxy group, or an acyl group having 2 to 4 carbon atoms is represented.
x represents an integer of 0 to 8. When x is 2 or more, the plurality of R ^b may be the same or different.
R ^a represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms, or may be bonded to a carbon atom contained in the ring W ′ to form a ring. ]

The hydrocarbon includes a saturated or unsaturated hydrocarbon group, and as described above, an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, an aryl, an aralkyl group, or a combination thereof. Can be mentioned.
Examples of the ring include an aromatic or non-aromatic hydrocarbon ring or a heterocyclic ring. These may be further combined to form a polycyclic fused ring.
x preferably represents an integer of 0 to 6, more preferably an integer of 0 to 4.
Examples of the ring W ′ include formula (W1) to formula (W25).

［式（Ｙ１）及び式（Ｙ２）中、
環に含まれる水素原子は、ハロゲン原子、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基又は炭素数２〜４のアシル基で置換されていてもよく、環に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
＊は、Ｘ^１との結合手を表す。］ Among these, Y ¹ is more preferably a group represented by the formula (Y1) or the formula (Y2).

[In Formula (Y1) and Formula (Y2),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or glycidyl. It may be substituted with an oxy group or an acyl group having 2 to 4 carbon atoms, and —CH ₂ — contained in the ring may be replaced with —O— or —CO—.
* Represents a bond to ^{X 1.} ]

Y ¹ is a group in which a hydrogen atom contained in ring W ′ is not substituted or substituted only with a hydrocarbon group (provided that the methylene group contained in ring W ′ is substituted with an oxygen atom). And a group substituted with a hydroxyl group or a group containing a hydroxyl group (excluding those having a lactone structure) and two adjacent methylene groups contained in the ring W ′ are an oxygen atom and a carbonyl group. A group having a substituted lactone structure and a group having a ketone structure in which one methylene group contained in ring W ′ is substituted with a carbonyl group, and a hydrogen atom contained in ring W ′ represents an aromatic hydrocarbon group or an aromatic ring. And a group having an ether structure in which one methylene group contained in the ring W ′ is substituted with an oxygen atom, and the like.

The hydrogen atom contained in the ring W ′ is not substituted or substituted only with a hydrocarbon group (the methylene group contained in the hydrocarbon group may be substituted with an oxygen atom) as Y ¹ For example, the following groups may be mentioned.

Examples of Y ¹ in which a hydrogen atom contained in ring W ′ is substituted with a hydroxyl group or a group containing a hydroxyl group (however, having no lactone structure) include the following groups.

Examples of Y ¹ having a lactone structure in which two adjacent methylene groups contained in ring W ′ are substituted with a carbonyl group and an oxygen atom include the following groups.

Examples of Y ¹ having a ketone structure in which one methylene group contained in ring W ′ is substituted with a carbonyl group include the following groups.

Examples of Y ¹ in which the hydrogen atom contained in the ring W ′ is substituted with an aromatic hydrocarbon group or a group having an aromatic ring include the following groups.

Examples of Y ¹ having an ether structure in which one methylene group contained in ring W ′ is substituted with an oxygen atom include the following groups.

  In formula (IIIA), an anion in which a hydrogen atom contained in ring W ′ is substituted only with a hydrocarbon group (a methylene group contained in the hydrocarbon group may be substituted with an oxygen atom) includes, for example, The following can be mentioned.

  In the formula (IIIA), examples of the anion in which the hydrogen atom contained in the ring W ′ is substituted with a hydroxyl group or a group containing a hydroxyl group (but not having a lactone structure) include the following.

  In formula (IIIA), examples of the anion having a lactone structure in which two adjacent methylene groups contained in ring W ′ are substituted with an oxygen atom and a carbonyl group include the following.

  In formula (IIIA), examples of the anion having a ketone structure in which the methylene group contained in the ring W ′ is substituted with a carbonyl group include the following.

  In formula (IIIA), examples of the anion in which the hydrogen atom contained in ring W ′ is substituted with an aromatic hydrocarbon group or a group having an aromatic ring include the following.

  In formula (IIIA), examples of the anion having an ether structure in which the methylene group contained in the ring W ′ is substituted with an oxygen atom include the following.

  In formula (IIIB), a hydrogen atom contained in ring W ′ is not substituted or substituted only with a hydrocarbon group (a methylene group contained in ring W ′ may be substituted with an oxygen atom). Examples of the anion include the following.

  In formula (IIIB), examples of the anion in which the hydrogen atom contained in ring W ′ is substituted with a hydroxyl group or a group containing a hydroxyl group include the following.

  In the formula (IIIB), examples of the anion having a lactone structure in which two adjacent methylene groups included in the ring W ′ are substituted with an oxygen atom and a carbonyl group include the followings.

  In the formula (IIIB), examples of the anion having a ketone structure in which one methylene group contained in the ring W ′ is substituted with a carbonyl group include the followings.

  In the formula (IIIB), examples of the anion in which the hydrogen atom contained in the ring W ′ is substituted with an aromatic hydrocarbon group include the following.

  In formula (IIIC), the hydrogen atom contained in ring W ′ is not substituted or substituted only with a hydrocarbon group (the methylene group contained in ring W ′ may be substituted with an oxygen atom). Examples of the anion include the following.

  In the formula (IIIC), examples of the anion in which the hydrogen atom contained in the ring W ′ is substituted with a hydroxyl group or a group containing a hydroxyl group include the following.

  In the formula (IIIC), examples of the anion having a ketone structure in which one methylene group contained in the ring W ′ is substituted with a carbonyl group include the followings.

  In formula (IIID), the hydrogen atom contained in ring W ′ is not substituted or substituted only with a hydrocarbon group (the methylene group contained in ring W ′ may be substituted with an oxygen atom). Examples of the anion include the following.

  In formula (IIID), examples of the anion in which the hydrogen atom contained in ring W ′ is substituted with a hydroxyl group or a group containing a hydroxyl group include the following.

  In the formula (IIID), examples of the anion having a ketone structure in which one methylene group contained in the ring W ′ is substituted with a carbonyl group include the following.

Examples of Z ^{+ in the} salt represented by the formula (III) include onium cations such as sulfonium cations, iodonium cations, ammonium cations, benzothiazolium cations, and phosphonium cations. Among these, a sulfonium cation and an iodonium cation are preferable, and an arylsulfonium cation is more preferable.

Z ⁺ is preferably any one of cations represented by formulas (IIIa) to (IIId).

In formula (IIIa), P ^a , P ^b and P ^c are each independently a linear or branched aliphatic hydrocarbon group having 1 to 30 carbon atoms or an alicyclic group having 3 to 30 carbon atoms. It represents a hydrocarbon group or an aromatic hydrocarbon group having 6 to 20 carbon atoms.
These aliphatic hydrocarbon group and aromatic hydrocarbon group may be substituted with a hydroxy group or a linear or branched alkoxy group having 1 to 12 carbon atoms. The aromatic hydrocarbon group may be substituted with a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 4 to 36 carbon atoms.

In formula (IIIb), P ⁴ and P ⁵ are each independently a hydrogen atom, a hydroxy group, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, a linear or branched group A chain-like C1-C12 alkoxy group is represented.

In formula (IIIc), P ⁶ and P ⁷ are each independently a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, a C 3 to 36 carbon atoms (preferably 4 carbon atoms). Represents an alicyclic hydrocarbon group (˜12).
P ⁸ is a hydrogen atom, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 36 carbon atoms, or an aromatic carbon atom having 6 to 20 carbon atoms. Represents a hydrogen group. Preferably it is a hydrogen atom.
P ⁹ is a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms. To express.
However, the aromatic hydrocarbon groups of P ⁸ and P ⁹ are linear or branched aliphatic hydrocarbon groups having 1 to 12 carbon atoms, alicyclic hydrocarbon groups having 3 to 12 carbon atoms, hydroxy It may be substituted with a group or a linear or branched alkoxy group having 1 to 12 carbon atoms. Even if P ⁶ and P ⁷ are combined or P ⁸ and P ⁹ are combined to form a 3-membered ring to 12-membered ring (preferably a 3-membered ring to 6-membered ring) Good. These rings _-CH 2 - is, -O -, - S -, - CO- may be substituted with.

In formula (IIId), P ^{10 to} P ²¹ each independently represent a hydroxy group, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, a linear or branched chain An alkoxy group having 1 to 12 carbon atoms is represented.
E represents a sulfur atom or an oxygen atom.
m represents 0 or 1.

Examples of the aliphatic hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, alkoxy group and the like are the same as those described above.
Examples of the 3-membered to 12-membered ring formed by P ⁶ and P ⁷ or P ⁸ and P ⁹ together include alicyclic hydrocarbons and aromatic hydrocarbons.
Specifically, examples of the ring formed by P ⁶ and P ⁷ include a thiolane-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, a 1,4-oxathian-4-ium ring, and the like. Is mentioned.
Examples of the ring formed by P ⁸ and P ⁹ include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

  Among the cations of the formulas (IIIa) to (IIId), the triphenylsulfonium cation represented by the following formula (IIIe) is more preferable.

In formula (IIIe), P ^{1 to} P ³ each independently represent a hydrogen atom, a hydroxyl group, a halogen atom, a linear or branched C 1-12 aliphatic hydrocarbon group, a linear or branched group. Or an alicyclic hydrocarbon having 4 to 36 carbon atoms. The hydrogen atom contained in the alicyclic hydrocarbon group is a halogen atom, a hydroxyl group, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, or a linear or branched carbon number of 1 to 12. Or an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, or an acyl group having 2 to 4 carbon atoms.
In particular, those containing an adamantyl skeleton and an isobornyl skeleton are suitable as the alicyclic hydrocarbon group, preferably a 2-alkyl-2-adamantyl group, a 1- (1-adamantyl) -1-alkyl group, an isobornyl group, and the like. Is mentioned.

  Examples of the cation represented by the formula (IIIa) or the formula (IIIe) include the followings.

Specific examples of the cation (IIIb) include the following.

Specific examples of the cation (IIIc) include the following.

Specific examples of the cation (IIId) include the following.

なかでも、Ｚ^＋は、アリールスルホニウムカチオンであるものが好ましい。
上述したアニオン及びカチオンは、任意に組合せることができる。

Among these, Z ⁺ is preferably an arylsulfonium cation.
The anions and cations described above can be arbitrarily combined.

［式（Ｘａ）〜（Ｘｉ）中、
Ｐ^２５、Ｐ^２６及びＰ^２７は、互いに独立に、水素原子、直鎖状又は分岐状の炭素数１〜４の脂肪族炭化水素基あるいは炭素数４〜３６の脂環式炭化水素基を表す。
Ｐ^２８及びＰ^２９は、互いに独立に、直鎖状又は分岐状の炭素数１〜１２の脂肪族炭化水素基あるいは炭素数４〜３６の脂環式炭化水素基を表すか、あるいはＰ^２８とＰ^２９とが一緒になってＳ^＋を含んで炭素数２〜６の環を形成してもよい。
Ｐ^３０は、直鎖状又は分岐状の炭素数１〜１２の脂肪族炭化水素基、炭素数４〜３６の脂環式炭化水素基あるいは置換されていてもよい炭素数６〜２０の芳香族炭化水素基を表すか、あるいはＰ^３０とＰ^３１とが一緒になって炭素数３〜１２の環を形成してもよい。ここで、該環に含まれるメチレン基は、任意に、酸素原子、硫黄原子又はカルボニル基で置換されていてもよい。
Ｑ^１及びＱ^２は、上記と同義である。
Ｘ^１３は、単結合又はメチレン基を表す。］ For example, examples of the salt represented by the formula (III) include compounds represented by the formula (Xa) to the formula (Xi).

[In the formulas (Xa) to (Xi),
P ²⁵ , P ²⁶ and P ²⁷ each independently represent a hydrogen atom, a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group having 4 to 36 carbon atoms. .
P ²⁸ and P ²⁹ each independently represent a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 4 to 36 carbon atoms, or P ²⁸ and may form a ring of 2 to 6 carbon atoms include S ⁺ and P ²⁹ together.
P ³⁰ is a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 4 to 36 carbon atoms, or an optionally substituted aromatic group having 6 to 20 carbon atoms. It may represent a hydrocarbon group, or P ³⁰ and P ³¹ may form a ring having 3 to 12 carbon atoms together. Here, the methylene group contained in the ring may be optionally substituted with an oxygen atom, a sulfur atom or a carbonyl group.
Q ¹ and Q ² are as defined above.
X ¹³ represents a single bond or a methylene group. ]

Examples of the ring and P ²⁸ and P ²⁹ are formed together, such as tetrahydrothiophenium group.
Examples of the ring formed by combining P ³⁰ and P ³¹ include the groups of the above-described formulas (W13) to (W15).

Of the above combinations, the following salts are preferred.

Especially, in the cation represented by the formula (IIIe) as the cation, specific examples of the triphenylsulfonium cation in which P ²² , P ²³ and P ²⁴ are all hydrogen atoms and the anion represented by the formula (IB) Acid generators in combination with those listed above are preferred.
You may use the acid generator represented by Formula (III) individually or in combination of 2 or more types.

In the acid generator (A) represented by the formula (III), the salt when the cation is Z ⁺ can be formed by the following production method. In addition, in the formula shown with the manufacturing method of the following acid generators, unless otherwise specified, the definition of each substituent shows the same meaning as described above.

For example, the salt represented by the formula (1) and the onium salt represented by the formula (3) are mixed in an inert solvent such as acetonitrile, water, methanol, chloroform, methylene chloride, or an aprotic solvent. Thus, it can be produced by a method of stirring and reacting in a temperature range of about 0 to 150 ° C., preferably about 0 to 100 ° C.
Here, examples of the aprotic solvent include dichloroethane, toluene, ethylbenzene, monochlorobenzene, acetonitrile, N, N-dimethylformamide and the like.

［式中、Ｍ^＋は、Ｌｉ^＋、Ｎａ^＋、Ｋ^＋又はＡｇ^＋を表す。
Ｚ^１−は、Ｆ⁻、Ｃｌ⁻、Ｂｒ⁻、Ｉ⁻、ＢＦ_４ ⁻、ＡｓＦ_６ ⁻、ＳｂＦ_６ ⁻、ＰＦ_６ ⁻又はＣｌＯ_４ ⁻を表す。］

[Wherein M ⁺ represents Li ⁺ , Na ⁺ , K ⁺ or Ag ⁺ .
Z ¹⁻ represents F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , BF ₄ ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , PF ₆ ⁻ or ClO ₄ ⁻ . ]

  The usage-amount of the onium salt of Formula (3) is about 0.5-2 mol normally with respect to 1 mol of salts represented by Formula (1). The salt may be taken out by recrystallization or may be purified by washing with water.

  Among the salts represented by the formula (1), the salt having an anion represented by the formula (IIIA) is, for example, first represented by the alcohol represented by the formula (4) and the formula (5). It can be obtained by esterification reaction with carboxylic acid.

  The amount of the carboxylic acid represented by the formula (5) in the esterification reaction is usually about 0.2 to 3 mol, preferably 0.5 to 1 mol of the alcohol represented by the formula (4). About 2 moles. The amount of the acid catalyst used in the esterification reaction may be a catalytic amount or an amount corresponding to a solvent, and is usually about 0.001 to 5 mol.

Moreover, among the salts represented by the formula (1), the salt having an anion represented by the formula (IIIA) includes, for example, an alcohol represented by the formula (6) and a carboxyl represented by the formula (7). It can also be produced by esterifying the acid and then hydrolyzing with MOH.

  Examples of the alkali metal hydroxide represented by MOH include lithium hydroxide, sodium hydroxide and potassium hydroxide, preferably lithium hydroxide and sodium hydroxide.

The esterification reaction is usually carried out by stirring in an aprotic solvent similar to the above in a temperature range of about 20 to 200 ° C, preferably in a temperature range of about 50 to 150 ° C.
In the esterification reaction, an organic acid such as p-toluenesulfonic acid or an inorganic acid such as sulfuric acid may be added as an acid catalyst.
Furthermore, a dehydrating agent may be added in the esterification reaction.
Examples of the dehydrating agent include dicyclohexylcarbodiimide, 1-alkyl-2-halopyridinium salt, 1,1-carbonyldiimidazole, bis (2-oxo-3-oxazolidinyl) phosphine acid chloride, 1-ethyl-3- (3 -Dimethylaminopropyl) carbodiimide hydrochloride, di-2-pyridyl carbonate, di-2-pyridylthiono carbonate, 6-methyl-2-nitrobenzoic anhydride in the presence of 4- (dimethylamino) pyridine, and the like. The esterification reaction using an acid catalyst is preferably carried out while dehydrating using a Dean Stark apparatus or the like because the reaction time tends to be shortened.

  The above reaction can be similarly applied to the production of a salt having an anion represented by the formula (IIIB).

  Further, among the salts represented by the formula (1), the salt having an anion represented by the formula (IIIC) is, for example, first represented by the carboxylic acid represented by the formula (8) and the formula (9). It can be obtained by an esterification reaction with the alcohol to be produced.

  The amount of the alcohol represented by the formula (9) in the esterification reaction is about 0.5 to 3 mol, preferably about 1 to 2 mol with respect to 1 mol of the carboxylic acid represented by the formula (8). is there. The acid catalyst in the esterification reaction may be a catalytic amount or an amount corresponding to a solvent with respect to 1 mol of the carboxylic acid represented by the formula (8), and is usually about 0.001 to 5 mol. The dehydrating agent in the esterification reaction is about 0.5 to 5 mol, preferably about 1 to 3 mol with respect to 1 mol of the carboxylic acid represented by the formula (8).

  In the esterification reaction of the carboxylic acid represented by the formula (8) and the alcohol represented by the formula (9), the carboxylic acid represented by the formula (8) is converted into the corresponding acid halide, and the formula (9 It can also be performed by reacting with an alcohol represented by

Examples of the reagent that converts to an acid halide include thionyl chloride, thionyl bromide, phosphorus trichloride, phosphorus pentachloride, and phosphorus tribromide. Examples of the solvent used in the acid halide reaction include the same aprotic solvents as described above. The reaction is suitably carried out with stirring in a temperature range of about 20 to 200 ° C., preferably in a temperature range of about 50 to 150 ° C.
In the above reaction, an amine compound may be added as a catalyst.

By reacting the obtained acid halide with an alcohol represented by the formula (9) in an inert solvent (for example, an aprotic solvent), a salt having an anion represented by the formula (IIIC) is obtained. be able to. The reaction is preferably performed in a temperature range of about 20 to 200 ° C, and more preferably in a temperature range of about 50 to 150 ° C. It is also suitable to use a deoxidizer.
Examples of the deoxidizer include organic bases such as triethylamine and pyridine, or inorganic bases such as sodium hydroxide, potassium carbonate, and sodium hydride.
The amount of the deoxidizing agent used may be an amount corresponding to the solvent with respect to 1 mol of the acid halide, and is usually about 0.001 to 5 mol, preferably about 1 to 3 mol.

As a method for producing a salt having an anion represented by (IIIC), an esterification reaction is performed between a carboxylic acid represented by formula (10) and an alcohol represented by formula (11), and then represented by MOH. There is also a method of obtaining a salt by hydrolysis with an alkali metal hydroxide. M ⁺ represents the same meaning as described above.

The esterification reaction of the carboxylic acid represented by the formula (10) and the alcohol represented by the formula (11) is usually performed in a temperature range of about 20 to 200 ° C. in the same aprotic solvent as described above. Preferably, stirring may be performed in a temperature range of about 50 to 150 ° C.
In the esterification reaction, the same acid catalyst as described above is usually added.
Furthermore, in this esterification reaction, a dehydrating agent may be added as described above.

  Examples of the method for producing a salt having an anion represented by the formula (IIID) include a method of dehydrating and condensing the alcohol represented by the formula (12) and the alcohol represented by the formula (13). It is done.

  Moreover, as a manufacturing method of the salt which has an anion represented by Formula (IIID), after reacting the alcohol represented by Formula (14) and the alcohol represented by Formula (15), it represents with MOH. There is also a method of dehydrating and condensing with an alkali metal hydroxide.

The reaction of the alcohol represented by the formula (14) and the alcohol represented by the formula (15) is usually in a temperature range of about 20 to 200 ° C., preferably 50 to 150 ° C. in an aprotic solvent. What is necessary is just to stir in the temperature range of about.
In the reaction, an acid catalyst is usually used.
Further, in the reaction, the above-described dehydrating agent may be added.
The reaction using an acid catalyst is preferably carried out while dehydrating using a Dean Stark apparatus or the like because the reaction time tends to be shortened.

  The amount of the alcohol represented by the formula (14) in the reaction is about 0.5 to 3 mol, preferably about 1 to 2 mol per 1 mol of the alcohol represented by the formula (15). . The acid catalyst in the etherification reaction may be a catalytic amount or an amount corresponding to a solvent with respect to 1 mol of the alcohol represented by the formula (15), and is usually about 0.001 to 5 mol. The dehydrating agent in the etherification reaction is about 0.5 to 5 mol, preferably about 1 to 3 mol per 1 mol of the alcohol represented by the formula (15).

  The reaction between the alcohol represented by the formula (16) and the alcohol represented by the formula (17) is obtained by converting the alcohol represented by the formula (17) into a compound represented by the formula (18). It can also be carried out by reacting the compound represented by the formula (18) with the alcohol represented by the formula (16).

［式中、Ｌは、塩素、臭素、ヨウ素、メシルオキシ基、トシルオキシ基又はトリフルオロメタンスルホニルオキシ基を表す。］

[Wherein L represents chlorine, bromine, iodine, mesyloxy group, tosyloxy group or trifluoromethanesulfonyloxy group. ]

In order to convert the alcohol represented by the formula (17) into the compound represented by the formula (18), for example, thionyl chloride, thionyl bromide, phosphorus trichloride, phosphorus pentachloride, phosphorus tribromide, mesyl chloride, Tosyl chloride, trifluoromethanesulfonic anhydride and the like are reacted with the alcohol represented by the formula (17).
Said reaction is performed in the inert solvent mentioned above. The reaction is carried out with stirring in a temperature range of about -70 to 200 ° C, preferably in a temperature range of about -50 to 150 ° C. It is also suitable to use a deoxidizer as described above.
The amount of the base used may be an amount corresponding to a solvent with respect to 1 mol of the alcohol represented by the formula (17), and is usually about 0.001 to 5 mol, preferably about 1 to 3 mol.

A salt having an anion represented by formula (IIID) can be obtained by reacting the obtained compound represented by formula (18) with an alcohol represented by formula (16) in an inert solvent. it can. The reaction is carried out in a temperature range of about 20 to 200 ° C, preferably in a temperature range of about 50 to 150 ° C.
In the reaction, it is suitable to use a deoxidizing agent.
When using a deoxidizing agent, the amount thereof may be an amount corresponding to a solvent with respect to 1 mol of the compound represented by the formula (18), and is usually about 0.001 to 5 mol, preferably 1 to 3 mol. It is about a mole.

  In addition, the manufacturing method of the cation in the acid generator represented by Formula (III) can be manufactured using any method known in the art.

  In the resist composition of the present invention, the content of the acid generator is preferably 1 to 20 parts by mass and more preferably 1 to 15 parts by mass with respect to 100 parts by mass of the resin (polymer). preferable.

  The resist composition of the present invention contains a basic compound, preferably a basic nitrogen-containing organic compound, particularly preferably an amine or ammonium salt. By adding a basic compound as a quencher, it is possible to improve the performance degradation due to the deactivation of the acid accompanying the holding after exposure. Specific examples of the basic compound used for the quencher include those represented by the following formulas.

式中、Ｔ^１０、Ｔ^２及びＴ^７は、互いに独立に、水素原子、炭素数１〜６の脂肪族炭化水素基、炭素数５〜１０の脂環式炭化水素基又は炭素数６〜２０の芳香族炭化水素基を表す。該脂肪族炭化水素基の水素原子、該脂環式炭化水素基の水素原子及び芳香族炭化水素基の水素原子は、水酸基、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い。該アミノ基の水素原子は、炭素数１〜４の脂肪族炭化水素基で置換されていてもよい。

In the formula, T ¹⁰ , T ² and T ⁷ are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 5 to 10 carbon atoms, or 6 to 20 carbon atoms. Represents an aromatic hydrocarbon group. The hydrogen atom of the aliphatic hydrocarbon group, the hydrogen atom of the alicyclic hydrocarbon group, and the hydrogen atom of the aromatic hydrocarbon group may be substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. Good. The hydrogen atom of the amino group may be substituted with an aliphatic hydrocarbon group having 1 to 4 carbon atoms.

T ^{3 to} T ⁵ are each independently a hydrogen atom, a linear or branched aliphatic hydrocarbon group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, carbon An alicyclic hydrocarbon group having 5 to 10 carbon atoms or an aromatic hydrocarbon group having 6 to 20 carbon atoms is represented. The hydrogen atom of the aliphatic hydrocarbon group, the hydrogen atom of the alicyclic hydrocarbon group, the hydrogen atom of the aromatic hydrocarbon group and the hydrogen atom of the alkoxy group are independently of each other a hydroxyl group, an amino group or a straight chain. Or a branched or branched alkoxy group having 1 to 6 carbon atoms. The hydrogen atom of the amino group may be substituted with a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms.

T ⁶ represents a linear or branched aliphatic hydrocarbon group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 10 carbon atoms. The hydrogen atom of the aliphatic hydrocarbon group or the hydrogen atom of the alicyclic hydrocarbon group is independently substituted with a hydroxyl group, an amino group, or a linear or branched alkoxy group having 1 to 6 carbon atoms. May be. The hydrogen atom of the amino group may be substituted with a linear or branched aliphatic hydrocarbon group having 1 to 4 carbon atoms.

  A represents an alkylene group having 2 to 6 carbon atoms, a carbonyl group, an imino group, a sulfanediyl group, or a disulfanediyl group.

  Specific examples of such compounds include hexylamine, heptylamine, octylamine, nonylamine, decylamine, aniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, 1- or 2-naphthylamine, and ethylenediamine. , Tetramethylenediamine, hexamethylenediamine, 4,4′-diamino-1,2-diphenylethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′- Diethyldiphenylmethane, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, N-methylaniline, piperidine, diphenylamine, triethylamine, trimethylamine, tripropylamine, tributylamine , Tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine Methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine, N, N-dimethylaniline, 2,6-isopropylaniline, imidazole, pyridine, -Methylpyridine, 4-methylimidazole, bipyridine, 2,2'-dipyridylamine, di-2-pyridyl ketone, 1,2-di (2-pyridyl) ethane, 1,2-di (4-pyridyl) ethane, 1,3-di (4-pyridyl) propane, 1,2-bis (2-pyridyl) ethylene, 1,2-bis (4-pyridyl) ethylene, 1,2-bis (4-pyridyloxy) ethane, 4 , 4′-dipyridyl sulfide, 4,4′-dipyridyl disulfide, 1,2-bis (4-pyridyl) ethylene, 2,2′-dipicolylamine, 3,3′-dipicolylamine, tetramethylammonium hydroxide Tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetra-n-hexylammonium hydroxide, tetra-n- Examples include octylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-trifluoromethylphenyltrimethylammonium hydroxide, (2-hydroxyethyl) trimethylammonium hydroxide (common name: choline), and the like.

  Furthermore, a hindered amine compound having a piperidine skeleton as disclosed in JP-A-11-52575 can be used as a quencher.

The resist composition of the present invention preferably contains about 80 to 99.9% by weight of resin and about 0.1 to 20% by weight of acid generator based on the total solid content.
Further, when a basic compound that is a quencher is used as the chemically amplified resist composition, it is preferably contained in a range of about 0.01 to 1% by weight based on the total solid content of the resist composition.
The resist composition can further contain small amounts of various additives such as sensitizers, dissolution inhibitors, other resins, surfactants, stabilizers, and dyes as necessary.

  The resist composition of the present invention is usually used as a resist solution composition in a state in which each of the above components is dissolved in a solvent, and is usually used in industrial processes such as spin coating on a substrate such as a silicon wafer. Applied by. The solvent used here may be any solvent that dissolves each component, has an appropriate drying rate, and gives a uniform and smooth coating film after the solvent evaporates, and is usually used industrially in this field. A solvent can be used.

  For example, 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, esters such as ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate And ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone, and cyclic esters such as γ-butyrolactone. These solvents can be used alone or in combination of two or more.

The pattern forming method of the present invention comprises:
(1) The process of apply | coating the resist composition of this invention mentioned above on a board | substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer using an exposure machine (particularly an immersion exposure machine is preferred);
(4) A step of heating the composition layer after exposure,
(5) The process which develops the composition layer after a heating using a image development apparatus is included.

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

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

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

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

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.
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, three columns are “TSKgel Multipore HXL-M”, and the solvent is tetrahydrofuran) using polystyrene as a standard product. .

Column: TSKgel Multipore H _XL -M x 3 + guardcolumn (manufactured by Tosoh Corporation)
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min
Detector: RI detector Column temperature: 40 ° C
Injection volume: 100 μl
Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation)

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

(Synthesis of Resin B1)
Monomer E, monomer F, monomer I, monomer G and monomer D are charged in a molar ratio of 40: 10: 8: 26: 16, and then 1.2 mass times dioxane with respect to the total mass of all monomers. Was added. To the obtained mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added as initiators in proportions of 1 mol% and 3 mol%, respectively, with respect to the total number of moles of all monomers. This was heated at 75 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a large amount of methanol / water mixed solvent and precipitating three times to obtain a copolymer having a weight average molecular weight of about 7.4 × 10 ^{3 in} a yield of 68%. Got in. The obtained copolymer has a repeating unit derived from each monomer of the following formula, and this was designated as resin B1.

(Synthesis of Resin B2)
Monomer E, monomer F, monomer I, monomer G and monomer D are charged in a molar ratio of 40: 10: 5: 25: 20, and then 1.2 mass times dioxane with respect to the total mass of all monomers. Was added. To the obtained mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added as initiators in proportions of 1 mol% and 3 mol%, respectively, with respect to the total number of moles of all monomers. This was heated at 75 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a large amount of methanol / water mixed solvent and precipitating three times to obtain a copolymer having a weight average molecular weight of about 7.2 × 10 ^{3 in} a yield of 72%. Got in. The obtained copolymer has a repeating unit derived from each monomer of the above formula, and this was designated as resin B2.

(Synthesis of Resin B3)
Monomer E, monomer F, monomer I, monomer B, monomer G and monomer D are charged in a molar ratio of 40: 10: 4: 4: 22: 20, and then 1. Two times as much dioxane was added. To the obtained mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added as initiators in proportions of 1 mol% and 3 mol%, respectively, with respect to the total number of moles of all monomers. This was heated at 75 ° C. for about 5 hours. Then, the reaction solution was purified by performing the operation of pouring into a large amount of methanol / water mixed solvent and precipitating three times to obtain a copolymer having a weight average molecular weight of about 7.3 × 10 ^{3 in} a yield of 65%. Got in. The obtained copolymer has a repeating unit derived from each monomer of the following formula, and this was designated as resin B3.

〔樹脂Ｘ２の合成〕
モノマーＧ、モノマーＡ、モノマーＪをモル比４２．６：４１．４：１６．０で仕込み、全モノマー量の１．５重量倍のジオキサンを加えて溶液とした。そこに開始剤としてアゾビスイソブチロニトリルとアゾビス（２，４−ジメチルバレロニトリル）を全モノマー量に対してそれぞれ１ｍｏｌ％、３ｍｏｌ％添加し、７５℃で約５時間加熱した。その後、反応液を、大量のメタノールと水の混合溶媒に注いで沈殿させる操作を３回行って精製し、重量平均分子量が約７．３×１０^３の共重合体を収率６２％で得た。この共重合体は、次式モノマーに由来する繰り返し単位を有するものであり、これを樹脂Ｘ２とする。

〔樹脂Ｘ３の合成〕
モノマーＧ、モノマーＡ、モノマーＪをモル比３１．５：５２．７：１５．８で仕込み、全モノマー量の４．０重量倍のメチルエチルケトンを加えて溶液とした。そこに開始剤としてＶ−６０１（和光純薬製）を全モノマー量に対してそれぞれ５ｍｏｌ％添加し、７５℃で約７時間加熱した。その後、反応液を、大量のメタノールと水の混合溶媒に注いで沈殿させる操作を３回行って精製し、重量平均分子量が約７．３×１０^３の共重合体を収率５９％で得た。この共重合体は、上式モノマーに由来する繰り返し単位を有するものであり、これを樹脂Ｘ３とする。 [Synthesis of Resin X1]
Monomer A, monomer B, and monomer D were charged at a molar ratio of 50:25:25, and 1.5 weight times dioxane of the total monomer amount was added to prepare a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and heated at 77 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a mixed solvent of a large amount of methanol and water three times to obtain a copolymer having a weight average molecular weight of about 8.1 × 10 ^{3 in} a yield of 55%. It was. This copolymer has a repeating unit derived from the monomer of the following formula, and this is designated as resin X1.

[Synthesis of Resin X2]
Monomer G, monomer A, and monomer J were charged at a molar ratio of 42.6: 41.4: 16.0, and 1.5 weight times dioxane of the total monomer amount was added to obtain a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and heated at 75 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a mixed solvent of a large amount of methanol and water three times to obtain a copolymer having a weight average molecular weight of about 7.3 × 10 ^{3 in} a yield of 62%. It was. This copolymer has a repeating unit derived from the monomer of the following formula, and this is designated as resin X2.

[Synthesis of Resin X3]
Monomer G, monomer A, and monomer J were charged at a molar ratio of 31.5: 52.7: 15.8, and methyl ethyl ketone 4.0 times the total monomer amount was added to obtain a solution. V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) as an initiator was added thereto in an amount of 5 mol% with respect to the total monomer amount, and heated at 75 ° C. for about 7 hours. Thereafter, the reaction solution was purified by pouring it into a mixed solvent of a large amount of methanol and water three times to obtain a copolymer having a weight average molecular weight of about 7.3 × 10 ^{3 in} a yield of 59%. It was. This copolymer has a repeating unit derived from the above monomer, and is referred to as a resin X3.

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

Ａ２：

<Acid generator>
A1:

A2:

<Basic compound: Quencher>
Q1: 2,6-diisopropylaniline Q2: tri-n-pentylamine

<Solvent>
Propylene glycol monomethyl ether acetate 265 parts 2-heptanone 20.0 parts Propylene glycol monomethyl ether 20.0 parts γ-butyrolactone 3.5 parts

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

  In each resist film, an exposure amount at which the hole diameter of a pattern formed with a mask having a hole diameter of 70 nm was 55 nm was defined as effective sensitivity.

  Evaluation of resolution: In the case of resolving a pattern formed with a mask having a hole diameter smaller than 70 nm with reference to a resolution of a pattern formed with a mask having a hole diameter of 70 nm in terms of effective sensitivity. ◯, and a case where a pattern formed with a mask having a hole diameter smaller than 70 nm is not resolved is marked with ×.

  Shape evaluation: A pattern formed with a mask having a hole diameter of 70 nm was observed with a scanning electron microscope. A case where the top shape and the skirt shape were close to a rectangle was good, and a case where the top shape was round or close to a T-shape or a skirt was seen was judged as x.

  Focus margin (DOF) evaluation: In the effective sensitivity, the focus range where the hole diameter is 52.2 nm or more and 57.7 nm or less is assumed to be DOF, and the case where the DOF is larger than 0.15 μm is marked as ◯, and the case where the DOF is smaller than 0.15 μm. Judged as.

  Mask error factor (MEF) evaluation: In the effective sensitivity, the mask hole diameter of a pattern formed with a mask having a hole diameter of 72 nm, 71 nm, 70 nm, 69 nm, and 68 nm, respectively, is plotted on the horizontal axis, and the hole diameter of each pattern is plotted on the vertical axis. The slope of the straight line when plotted was calculated as MEF. The case where the inclination was less than 3.0 was judged as ◯, and the case where the inclination was larger than 3.0 was judged as x.

CD uniformity (CDU) evaluation: In terms of effective sensitivity, the hole diameter of a pattern formed with a mask having a hole diameter of 70 nm was measured 24 times per hole, and the average value was defined as the average hole diameter of one hole. A standard deviation is obtained from a population obtained by measuring 400 average hole diameters of a pattern formed with a mask having a hole diameter of 70 nm in the same wafer. The case of larger than 00 nm was judged as x.
These results are shown in Table 2.

  Since the resist composition of the present invention exhibits high resolution, good shape, good focus margin (DOF), good mask error factor (MEF) and good CD uniformity (CDU), excimers such as ArF and KrF are used. It can be used as a chemically amplified photoresist composition suitable for laser lithography, ArF immersion exposure lithography, and EUV exposure lithography. In addition to immersion exposure, it can also be used for dry exposure. Furthermore, it can be used for double imaging and is industrially useful.

Claims (10)

A resist composition comprising a resin having a repeating unit derived from a compound represented by formula (I) and a repeating unit derived from a compound represented by formula (II).

[In the formula (I),
R ¹ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
T represents an alicyclic hydrocarbon group having 4 to 36 carbon atoms, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, a hydroxyl group, a halogen atom or a hydroxyl group. An alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an acyl group having 2 to 4 carbon atoms, and 1 carbon atom 12 alkoxycarbonyl group, may be substituted with alkanoyloxy group or a cyano group having 1 to 12 carbon atoms, -CH 2 contained in the alicyclic hydrocarbon group _- at least one -SO ₂ It may be replaced by —CO—, —O—, —S—, —SO ₂ — or —N (R ² ) —.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. ]

[In the formula (II),
R ³ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
Z ¹ represents a C 1-17 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —CO—, —O—, —S. - or -N ^{(R 2)} - it may be replaced by.
R ⁴ and R ⁵ each independently represents a hydrogen atom, a methyl group or a hydroxyl group. However, at least one of R ⁴ and R ⁵ represents a hydroxyl group.
R ⁶ represents an alkyl group having 1 to 6 carbon atoms.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. ]
n represents an integer of 0 to 10. ] The resist composition according to claim 1, wherein T is a group represented by the formula (T1).

[In the formula (T1),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom or a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms. , An aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an acyl group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 1 to 12 carbon atoms, an alkanoyloxyalkyl group having 1 to 12 carbon atoms, or a cyano group. The —CH ₂ — contained in the ring may be replaced with at least one —SO ₂ —, and further —CO—, —O—, —S—, —SO ₂ — or —N (R ² )-May be replaced.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
* Represents a bond with -O-.
T ¹ represents —O—, —NH— or —CH ₂ —. ] The resist composition according to claim 1, wherein T is a group represented by the formula (T2).

[In the formula (T2),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom or a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms. , An aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an acyl group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 1 to 12 carbon atoms, an alkanoyloxyalkyl group having 1 to 12 carbon atoms, or a cyano group. The —CH ₂ — contained in the ring may be replaced by —CO—, —O—, —S—, —SO ₂ — or —N (R ² ) —.
R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
* Represents a bond with -O-. ]   The resin according to any one of claims 1 to 3, wherein the resin further has an acid labile group and is insoluble or hardly soluble in an alkaline aqueous solution, and the resin that has reacted with an acid is a resin that can be dissolved in an alkaline aqueous solution The resist composition as described.   The resist composition according to claim 1, comprising an acid generator. The composition according to claim 5, wherein the acid generator is an acid generator represented by the formula (III).

[In the formula (III),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
X ¹ represents a single bond or a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —O— or —CO—. It may be replaced with.
Y ¹ represents a linear or branched aliphatic hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, The aliphatic hydrocarbon group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a substituent. —CH ₂ — contained in the aliphatic hydrocarbon group, alicyclic hydrocarbon group and aromatic hydrocarbon group may be replaced by —O— or —CO—.
Z ⁺ represents an organic counter cation. ] The resist composition according to claim 5, wherein X ¹ is * —CO—O— (* represents a bond with —C (Q ¹ ) (Q ² ) —). The resist composition according to any one of claims 3 to 7, wherein Z ⁺ is an arylsulfonium cation.   The resist composition according to claim 1, comprising a basic compound. (1) The process of apply | coating the resist composition in any one of Claims 1-9 on a board | substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) A pattern forming method including a step of developing the heated composition layer using a developing device.