JP2014131980A - Salt, resin, resist composition and method of producing resist pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a salt for a resin to be used in a composition which makes it possible to obtain an excellent resist pattern.SOLUTION: This invention provides a salt represented by formula (I), where Ris represented by formula (IA) or formula (IE) and Yis represented by formula (Iy).

Description

  The present invention relates to a salt, a resin, a resist composition, and a method for producing a resist pattern.

Patent Document 1 describes a salt represented by the following formula and a resist composition containing the salt as an acid generator.

Patent Document 2 describes a resist composition containing a salt represented by the following formula and a resin containing a structural unit derived from the salt.

JP 2011-246439 A JP 2011-37836 A

  In the resist composition containing the salt represented by the above formula, the collapse margin during the production of the resist pattern may not always be sufficient.

［式（Ｉ）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^２は、炭素数１〜１７の２価の飽和炭化水素基を表し、前記２価の飽和炭化水素基に含まれる水素原子は、フッ素原子で置換されていてもよく、前記２価の飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｒ^３は、式（ＩＡ）

（式（ＩＡ）中、ｓ１は、１又は２を表す。ｔ１は、０又は１を表す。但し、ｓ１＋ｔ１は、１又は２である。
Ｒ^４は、炭素数１〜１２の飽和炭化水素基又は炭素数６〜１８の芳香族炭化水素基を表し、該飽和炭化水素基及び該芳香族炭化水素基に含まれる水素原子は、ニトロ基で置換されていてもよく、該飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−で置き換わっていてもよい。
ｕ１は、０〜４の整数を表す。ｕ１が２以上のとき、複数のＲ^４は同一又は相異なる。）又は式（ＩＥ）

（式（ＩＥ）中、環Ｗ^Ｅは、炭素数３〜９の脂環式炭化水素環を表す。
ｓ１２は、０〜４の整数を表す。
ｔ１２は、０〜２の整数を表す。但し、ｓ１２＋ｔ１２は、４以下である。
Ｒ^５及びＲ^６は、それぞれ独立に、ヒドロキシ基、ハロゲン原子、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１〜６のヒドロキシアルキル基、炭素数２〜７のアシル基、炭素数２〜７のアシルオキシ基又は炭素数２〜７のアシルアミノ基を表す。Ｒ^５及びＲ^６のうち２つが一緒になって環を形成してもよい。
ｕ２は、０〜１４の整数を表し、ｕ２が２以上のとき、複数のＲ^５は同一又は相異なる。
ｕ３は、０〜１３の整数を表し、ｕ３が２以上のとき、複数のＲ^６は同一又は相異なる。）
で表される基を表す。
Ｙ^１は、式（Ｉｙ）

（式（Ｉｙ）中、Ｒ’は、水素原子、フッ素原子を有してもよい炭素数１〜６のアルキル基、ヒドロキシ基又はシアノ基を表す。
Ｘ’は、単結合、−Ｏ−、＊−ＣＯ−Ｏ−、＊−Ａｒ−Ｏ−、＊−Ａｒ−ＣＯ−Ｏ−、＊−ＣＯ−Ｏ−Ａｒ−Ｏ−又は＊−ＣＯ−Ｏ−Ａｒ−ＣＯ−Ｏ−を表す。
Ａｒは、フェニレン基を表す。
＊は、−Ｃ（Ｒ’）＝ＣＨ_２との結合手を表す。）
で表される基を表す。
Ｒ¹及びＲ²は、それぞれ独立に、置換基を有していてもよい炭素数１〜１０の脂肪族炭化水素基、置換基を有してもよい炭素数４〜３６の脂環式炭化水素基、置換基を有していてもよい炭素数６〜３６の芳香族炭化水素基又は置換基を有していてもよい炭素数３〜３６の複素環基を表す。
Ｘ^１は、置換基を有していてもよい炭素数１〜３６の２価の炭化水素基を表し、該炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＳＯ_２−又は−ＣＯ−に置き換わっていてもよい。Ｒ^１、Ｒ^２及びＸ^１のうちの２つが一緒になって、硫黄原子を含む環を形成してもよい。］
〔２〕式（Ｉ）におけるＲ^３が、式（ＩＡ）で表される基である〔１〕記載の塩。
〔３〕〔１〕又は〔２〕記載の塩に由来する構造単位を含む樹脂。
〔４〕さらに、酸不安定基を有する構造単位を含む〔３〕記載の樹脂。
〔５〕〔１〕又は〔２〕記載の塩を含むレジスト組成物。
〔６〕〔３〕又は〔４〕記載の樹脂を含むレジスト組成物。
〔７〕〔１〕又は〔２〕記載の塩をさらに含む〔６〕記載のレジスト組成物。
〔８〕（１）〔５〕〜〔７〕のいずれかに記載のレジスト組成物を基板上に塗布する工程、
（２）塗布後の組成物を乾燥させて組成物層を形成する工程、
（３）組成物層に露光する工程、
（４）露光後の組成物層を加熱する工程及び
（５）加熱後の組成物層を現像する工程
を含むレジストパターンの製造方法。 The present invention includes the following inventions.
[1] A salt represented by the formula (I).

[In the formula (I),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
X ² represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom, and the divalent saturated hydrocarbon group —CH ₂ — contained in the hydrocarbon group may be replaced by —O— or —CO—.
R ³ represents formula (IA)

(In formula (IA), s1 represents 1 or 2. t1 represents 0 or 1, provided that s1 + t1 is 1 or 2.
R ⁴ represents a saturated hydrocarbon group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group and the aromatic hydrocarbon group is a nitro group. The —CH ₂ — contained in the saturated hydrocarbon group may be replaced with —O—.
u1 represents an integer of 0 to 4. When u1 is 2 or more, the plurality of R ⁴ are the same or different. ) Or formula (IE)

(In Formula (IE), Ring W ^E represents an alicyclic hydrocarbon ring having 3 to 9 carbon atoms.
s12 represents an integer of 0 to 4.
t12 represents an integer of 0 to 2. However, s12 + t12 is 4 or less.
R ⁵ and R ⁶ are each independently a hydroxy group, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, or 2 to 7 carbon atoms. An acyl group having 2 to 7 carbon atoms, or an acylamino group having 2 to 7 carbon atoms. Two of R ⁵ and R ⁶ may be combined to form a ring.
u2 represents an integer of 0 to 14, and when u2 is 2 or more, the plurality of R ⁵ are the same or different.
u3 represents an integer of 0 to 13, and when u3 is 2 or more, the plurality of R ⁶ are the same or different. )
Represents a group represented by
Y ¹ represents the formula (Iy)

(In formula (Iy), R ′ represents a hydrogen atom, a C 1-6 alkyl group which may have a fluorine atom, a hydroxy group or a cyano group.
X ′ represents a single bond, —O—, * —CO—O—, * —Ar—O—, * —Ar—CO—O—, * —CO—O—Ar—O— or * —CO—O. -Ar-CO-O- is represented.
Ar represents a phenylene group.
* Represents a bond with —C (R ′) ═CH ₂ . )
Represents a group represented by
R ¹ and R ² are each independently an optionally substituted aliphatic hydrocarbon group having 1 to 10 carbon atoms and an optionally substituted alicyclic carbon atom having 4 to 36 carbon atoms. A hydrogen group, an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent, or a heterocyclic group having 3 to 36 carbon atoms which may have a substituent.
X ¹ represents a C1-36 divalent hydrocarbon group which may have a substituent, and —CH ₂ — contained in the hydrocarbon group is —O—, —SO ₂ — or -CO- may be substituted. ^{Two of} R ¹ , R ² and X ¹ may be taken together to form a ring containing a sulfur atom. ]
[2] The salt according to [1], wherein R ³ in formula (I) is a group represented by formula (IA).
[3] A resin containing a structural unit derived from the salt according to [1] or [2].
[4] The resin according to [3], further comprising a structural unit having an acid labile group.
[5] A resist composition comprising the salt according to [1] or [2].
[6] A resist composition comprising the resin according to [3] or [4].
[7] The resist composition according to [6], further comprising the salt according to [1] or [2].
[8] (1) A step of applying the resist composition according to any one of [5] to [7] on a substrate,
(2) The process of drying the composition after application | coating and forming a composition layer,
(3) a step of exposing the composition layer;
(4) A method for producing a resist pattern, comprising a step of heating the composition layer after exposure, and (5) a step of developing the composition layer after heating.

  The resist composition of the present invention can produce a resist pattern with an excellent collapse margin.

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

［式（Ｉ）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^２は、２価の炭素数１〜１７の飽和炭化水素基を表し、前記２価の飽和炭化水素基に含まれる水素原子は、フッ素原子で置換されていてもよく、前記２価の飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｒ^３は、式（ＩＡ）

（式（ＩＡ）中、ｓ１は、１又は２を表す。ｔ１は、０又は１を表す。但し、ｓ１＋ｔ１は、１又は２である。
Ｒ^４は、炭素数１〜１２の飽和炭化水素基又は炭素数６〜１８の芳香族炭化水素基を表し、該飽和炭化水素基及び該芳香族炭化水素基に含まれる水素原子は、ニトロ基で置換されていてもよく、該飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−で置き換わっていてもよい。
ｕ１は、０〜４の整数を表す。ｕ１が２以上のとき、複数のＲ^４は同一又は相異なる。）又は式（ＩＥ）

（式（ＩＥ）中、環Ｗ^Ｅは、炭素数３〜９の脂環式炭化水素環を表す。
ｓ１２は、０〜４の整数を表す。
ｔ１２は、０〜２の整数を表す。但し、ｓ１２＋ｔ１２は、４以下である。
Ｒ^５及びＲ^６は、それぞれ独立に、ヒドロキシ基、ハロゲン原子、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１〜６のヒドロキシアルキル基、炭素数２〜７のアシル基、炭素数２〜７のアシルオキシ基又は炭素数２〜７のアシルアミノ基を表す。Ｒ^５及びＲ^６のうち２つが一緒になって環を形成してもよい。
ｕ２は、０〜１４の整数を表し、ｕ２が２以上のとき、複数のＲ^５は同一又は相異なる。
ｕ３は、０〜１３の整数を表し、ｕ３が２以上のとき、複数のＲ^６は同一又は相異なる。）
で表される基を表す。
Ｙ^１は、式（Ｉｙ）

（式（Ｉｙ）中、Ｒ’は、水素原子、フッ素原子を有してもよい炭素数１〜６のアルキル基、ヒドロキシ基又はシアノ基を表す。
Ｘ’は、単結合、−Ｏ−、＊−ＣＯ−Ｏ−、＊−Ａｒ−Ｏ−、＊−Ａｒ−ＣＯ−Ｏ−、＊−ＣＯ−Ｏ−Ａｒ−Ｏ−又は＊−ＣＯ−Ｏ−Ａｒ−ＣＯ−Ｏ−を表す。
Ａｒは、フェニレン基を表す。
＊は、−Ｃ（Ｒ’）＝ＣＨ_２との結合手を表す。）
で表される基を表す。
Ｒ^１及びＲ^２は、それぞれ独立に、置換基を有していてもよい炭素数１〜１０の脂肪族炭化水素基、置換基を有してもよい炭素数４〜３６の脂環式炭化水素基、置換基を有していてもよい炭素数６〜３６の芳香族炭化水素基又は置換基を有していてもよい炭素数３〜３６の複素環基を表す。
Ｘ^１は、置換基を有していてもよい炭素数１〜３６の２価の炭化水素基を表し、該炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＳＯ_２−又は−ＣＯ−に置き換わっていてもよい。Ｒ^１、Ｒ^２及びＸ^１のうちの２つが一緒になって、硫黄原子を含む環を形成してもよい。］ <Salt represented by formula (I)>
The salt of the present invention is a salt represented by the formula (I) (hereinafter sometimes referred to as “salt (I)”).

[In the formula (I),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
X ² represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom, and the divalent saturated —CH ₂ — contained in the hydrocarbon group may be replaced by —O— or —CO—.
R ³ represents formula (IA)

(In formula (IA), s1 represents 1 or 2. t1 represents 0 or 1, provided that s1 + t1 is 1 or 2.
R ⁴ represents a saturated hydrocarbon group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group and the aromatic hydrocarbon group is a nitro group. The —CH ₂ — contained in the saturated hydrocarbon group may be replaced with —O—.
u1 represents an integer of 0 to 4. When u1 is 2 or more, the plurality of R ⁴ are the same or different. ) Or formula (IE)

(In Formula (IE), Ring W ^E represents an alicyclic hydrocarbon ring having 3 to 9 carbon atoms.
s12 represents an integer of 0 to 4.
t12 represents an integer of 0 to 2. However, s12 + t12 is 4 or less.
R ⁵ and R ⁶ are each independently a hydroxy group, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, or 2 to 7 carbon atoms. An acyl group having 2 to 7 carbon atoms, or an acylamino group having 2 to 7 carbon atoms. Two of R ⁵ and R ⁶ may be combined to form a ring.
u2 represents an integer of 0 to 14, and when u2 is 2 or more, the plurality of R ⁵ are the same or different.
u3 represents an integer of 0 to 13, and when u3 is 2 or more, the plurality of R ⁶ are the same or different. )
Represents a group represented by
Y ¹ represents the formula (Iy)

(In formula (Iy), R ′ represents a hydrogen atom, a C 1-6 alkyl group which may have a fluorine atom, a hydroxy group or a cyano group.
X ′ represents a single bond, —O—, * —CO—O—, * —Ar—O—, * —Ar—CO—O—, * —CO—O—Ar—O— or * —CO—O. -Ar-CO-O- is represented.
Ar represents a phenylene group.
* Represents a bond with —C (R ′) ═CH ₂ . )
Represents a group represented by
R ¹ and R ² are each independently an optionally substituted aliphatic hydrocarbon group having 1 to 10 carbon atoms and an optionally substituted alicyclic carbon atom having 4 to 36 carbon atoms. A hydrogen group, an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent, or a heterocyclic group having 3 to 36 carbon atoms which may have a substituent.
X ¹ represents a C1-36 divalent hydrocarbon group which may have a substituent, and —CH ₂ — contained in the hydrocarbon group is —O—, —SO ₂ — or -CO- may be substituted. ^{Two of} R ¹ , R ² and X ¹ may be taken together to form a ring containing a sulfur atom. ]

  In the following description, the anion contained in the salt (I) may be referred to as “sulfonate anion” and the cation contained in the salt (I) may be referred to as “organic cation”.

［式（Ｉａ）中、Ｑ^１、Ｑ^２、Ｘ^２及びＲ^３は、上記と同じ意味を表す。］ <Sulphonate anion>
The sulfonate anion contained in the salt (I) is represented by the formula (Ia).

[In Formula (Ia), Q ¹ , Q ² , X ² and R ³ represent the same meaning as described above. ]

Examples of the perfluoroalkyl group of Q ¹ and Q ² include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluorotert-butyl group, and a perfluoropentyl group. And perfluorohexyl group.
In the formula (Ia), Q ¹ and Q ² are each independently preferably a trifluoromethyl group or a fluorine atom, more preferably a fluorine atom.

Examples of the divalent saturated hydrocarbon group for X ² include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and these A combination of two or more of the groups may be used.
Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1 , 6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group , Dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1, A linear alkanediyl group such as a 17-diyl group;
An alkyl group (particularly an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group); For example, ethane-1,1-diyl group, propane-1,1-diyl group, propane-2,2-diyl group, butane-1,3-diyl group, 2-methylpropane Branched alkanediyl groups such as -1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group and 2-methylbutane-1,4-diyl group;
Cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,2-diyl group, 1-methylcyclohexane-1,2-diyl group, cyclohexane-1,4-diyl group, cyclo A monocyclic divalent alicyclic saturated hydrocarbon group which is a cycloalkanediyl group such as an octane-1,2-diyl group or a cyclooctane-1,5-diyl group;
A polycyclic group such as norbornane-2,3-diyl group, norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. A bivalent alicyclic saturated hydrocarbon group etc. are mentioned.

Examples of the group in which —CH ₂ — contained in the saturated hydrocarbon group for X ² is replaced by —O— or —CO— are divalent represented by formula (b1-1) to formula (b1-6), for example. The group of is mentioned. These formulas are described in accordance with the formula (Ia) on the left and right, and are bonded to C (Q ¹ ) (Q ² ) — on the left side. The same applies to the following specific examples.

式（ｂ１−１）〜式（ｂ１−６）中、
Ｌ^ｂ２は、単結合又は炭素数１〜１５の２価の飽和炭化水素基を表す。
Ｌ^ｂ３は、単結合又は炭素数１〜１２の２価の飽和炭化水素基を表す。
Ｌ^ｂ４は、炭素数１〜１３の２価の飽和炭化水素基を表す。但しＬ^ｂ３及びＬ^ｂ4の炭素数上限は１３である。
Ｌ^ｂ５は、炭素数１〜１５の２価の飽和炭化水素基を表す。
Ｌ^ｂ６及びＬ^ｂ７は、それぞれ独立に、炭素数１〜１５の２価の飽和炭化水素基を表す。但しＬ^ｂ６及びＬ^ｂ７の炭素数上限は１６である。
Ｌ^ｂ８は、炭素数１〜１４の２価の飽和炭化水素基を表す。
Ｌ^ｂ９及びＬ^ｂ１０は、それぞれ独立に、炭素数１〜１１の２価の飽和炭化水素基を表す。但しＬ^ｂ９及びＬ^ｂ１０の炭素数上限は１２である。

In formula (b1-1) to formula (b1-6),
L ^b2 represents a single bond or a divalent saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 12 carbon atoms.
L ^b4 represents a C1-C13 divalent saturated hydrocarbon group. However, the upper limit of the carbon number of L ^b3 and L ^b4 is 13.
L ^b5 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^b6 and L ^b7 each independently represent a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. However, the upper limit of the carbon number of L ^b6 and L ^b7 is 16.
^Lb8 represents a C1-C14 bivalent saturated hydrocarbon group.
L ^b9 and L ^b10 each independently represent a divalent saturated hydrocarbon group having 1 to 11 carbon atoms. However, the upper limit of the carbon number of L ^b9 and L ^b10 is 12.

Among these, X ² is preferably a group represented by any one of formula (b1-1) to formula (b1-4), more preferably represented by formula (b1-1) or formula (b1-2). A group, more preferably a group represented by the formula (b1-1). Particularly preferred is a group represented by the formula (b1-1), wherein L ^b2 is a single bond or a methylene group.

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

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

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

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

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

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

The hydrogen atom contained in the saturated hydrocarbon group for X ² may be substituted with a fluorine atom.

［式（ＩＡ）中、ｓ１は、１又は２を表す。ｔ１は、０又は１を表す。但し、ｓ１＋ｔ１は、１又は２である。
Ｒ^４は、炭素数１〜１２の飽和炭化水素基又は炭素数６〜１８の芳香族炭化水素基を表し、該飽和炭化水素基及び該芳香族炭化水素基に含まれる水素原子は、ニトロ基で置換されていてもよく、該飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−で置き換わっていてもよい。
ｕ１は、０〜４の整数を表す。ｕ１が２以上のとき、複数のＲ^４は同一又は相異なる。
式（ＩＥ）中、環Ｗ^Ｅは、炭素数３〜９の脂環式炭化水素環を表す。
ｓ１２は、０〜４の整数を表す。
ｔ１２は、０〜２の整数を表す。但し、ｓ１２＋ｔ１２は、４以下である。
Ｒ^５及びＲ^６は、それぞれ独立に、ヒドロキシ基、ハロゲン原子、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１〜６のヒドロキシアルキル基、炭素数２〜７のアシル基、炭素数２〜７のアシルオキシ基又は炭素数２〜７のアシルアミノ基を表す。Ｒ^５及びＲ^６のうち２つが一緒になって環を形成してもよい。
ｕ２は、０〜１４の整数を表し、ｕ２が２以上のとき、複数のＲ^５は同一又は相異なる。
ｕ３は、０〜１３の整数を表し、ｕ３が２以上のとき、複数のＲ^６は同一又は相異なる。 R ³ represents a group represented by the formula (IA) or a group represented by the formula (IE).

[In formula (IA), s1 represents 1 or 2. t1 represents 0 or 1. However, s1 + t1 is 1 or 2.
R ⁴ represents a saturated hydrocarbon group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group and the aromatic hydrocarbon group is a nitro group. The —CH ₂ — contained in the saturated hydrocarbon group may be replaced with —O—.
u1 represents an integer of 0 to 4. When u1 is 2 or more, the plurality of R ⁴ are the same or different.
In formula (IE), ring W ^E represents an alicyclic hydrocarbon ring having 3 to 9 carbon atoms.
s12 represents an integer of 0 to 4.
t12 represents an integer of 0 to 2. However, s12 + t12 is 4 or less.
R ⁵ and R ⁶ are each independently a hydroxy group, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, or 2 to 7 carbon atoms. An acyl group having 2 to 7 carbon atoms, or an acylamino group having 2 to 7 carbon atoms. Two of R ⁵ and R ⁶ may be combined to form a ring.
u2 represents an integer of 0 to 14, and when u2 is 2 or more, the plurality of R ⁵ are the same or different.
u3 represents an integer of 0 to 13, and when u3 is 2 or more, the plurality of R ⁶ are the same or different.

Examples of the saturated hydrocarbon group for R ⁴ include an alkyl group, an alicyclic saturated hydrocarbon group, and a group obtained by combining these.
Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.
As the alicyclic saturated hydrocarbon group, examples of the monocyclic alicyclic saturated hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic saturated hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, a tricyclo [5.2.1.0 ^2.6 ] decyl group, and the like.
Examples of the group combining an alkyl group and an alicyclic saturated hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, and a methylnorbornyl group.
Of these, a cycloalkyl group, a cyclohexyl group, an adamantyl group and the like are preferable.
Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthranyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a biphenyl group, and an anthryl group. , Aryl groups such as phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl, and the like.

Examples of the halogen atom for R ⁵ and R ⁶ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the alkyl group are the same as those exemplified for R ⁴ .
Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentyloxy group, and an n-hexyloxy group. .
Examples of the hydroxyalkyl group include a hydroxymethyl group and a hydroxyethyl group.
Examples of the acyl group include an acetyl group, a propionyl group, a butyryl group, and a benzoyl group.
Examples of the acyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, and a benzoyloxy group.
Examples of the acylamino group include an acetylamino group, a propionylamino group, a butyrylamino group, and a benzoylamino group.
In the case where R ⁵ and R ⁶ are bonded to each other to form a ring, it is preferable to form two R ⁶ .
s1 is preferably 1, and t1 is preferably 0 or 1.
It is preferable that s12 + t12 is an integer of 0-2.

R ⁵ may be bonded to the bridgehead position of the ring W ^E and ether ring but, R ⁶ does not bind to該橋cephalic.
u2 and u3 are each independently preferably an integer of 0 to 6, more preferably an integer of 0 to 3.

The alicyclic hydrocarbon ring ring W ^E, for example, cyclopropane ring, cyclobutane ring, cyclopentane ring, cyclohexane ring, cycloalkane ring such as a cycloheptane ring; cyclopentene ring, cycloalkene rings such as cyclohexene ring; deca Examples thereof include alicyclic hydrocarbon rings such as hydronaphthalene ring, adamantane ring, norbornane ring, tricyclo [5.2.1.0 ^2.6 ] decane ring. Among these, a cycloalkane ring is preferable.

（式（ＩＦ）中、ｓ１１は、１〜４の整数を表す。ｔ１１は、０〜２の整数を表す。
Ｒ^５、Ｒ^６、ｓ１２、ｔ１２、ｕ２及びｕ３は、前記と同義である。） The group represented by the formula (IE) is preferably a group represented by the formula (IF).

(In the formula (IF), s11 represents an integer of 1 to 4. t11 represents an integer of 0 to 2.
R ⁵ , R ⁶ , s12, t12, u2 and u3 are as defined above. )

Examples of the group represented by the formula (IA) include the following groups.

Examples of the group represented by the formula (IE) include the following groups.

Examples of the group represented by the formula (IA) include the following groups.

Examples of the group represented by the formula (IE) include the following groups.

［式中、各符号はそれぞれ上記と同じ意味を表す。］ The sulfonate anion represented by the formula (Ia) is represented by, for example, a sulfonate anion represented by the formula (Ia-a) or a sulfonate anion represented by the formula (Ia-b). It is a sulfonate anion represented by Ia-a).

[Wherein each symbol represents the same meaning as described above. ]

Examples of the sulfonate anion represented by the formula (Ia) include the following anions.

Especially, as a sulfonate anion, the sulfonate anion represented by the following is preferable.

［式（Ｉｃ）中、Ｙ^１は、式（Ｉｙ）

（式（Ｉｙ）中、Ｒ’は、水素原子、フッ素原子を有してもよい炭素数１〜６のアルキル基、ヒドロキシ基又はシアノ基を表す。
Ｘ’は、単結合、−Ｏ−、＊−ＣＯ−Ｏ−、＊−Ａｒ−Ｏ−、＊−Ａｒ−ＣＯ−Ｏ−、＊−ＣＯ−Ｏ−Ａｒ−Ｏ−又は＊−ＣＯ−Ｏ−Ａｒ−ＣＯ−Ｏ−を表す。
Ａｒは、フェニレン基を表す。
＊は、−Ｃ（Ｒ’）＝ＣＨ_２との結合手を表す。）
で表される基を表す。
Ｒ^１及びＲ^２は、それぞれ独立に、置換基を有していてもよい炭素数１〜１０の脂肪族炭化水素基、置換基を有してもよい炭素数４〜３６の脂環式炭化水素基、置換基を有していてもよい炭素数６〜３６の芳香族炭化水素基又は置換基を有していてもよい炭素数３〜３６の複素環基を表す。
Ｘ^１は、置換基を有していてもよい炭素数１〜３６の２価の炭化水素基を表し、該炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＳＯ_２−又は−ＣＯ−に置き換わっていてもよい。Ｒ^１、Ｒ^２及びＸ^１のうちの２つが一緒になって、硫黄原子を含む環を形成してもよい。］ <Organic cation>
The organic cation contained in the salt (I) is represented by the formula (Ic).

[In Formula (Ic), Y ¹ represents Formula (Iy)

(In formula (Iy), R ′ represents a hydrogen atom, a C 1-6 alkyl group which may have a fluorine atom, a hydroxy group or a cyano group.
X ′ represents a single bond, —O—, * —CO—O—, * —Ar—O—, * —Ar—CO—O—, * —CO—O—Ar—O— or * —CO—O. -Ar-CO-O- is represented.
Ar represents a phenylene group.
* Represents a bond with —C (R ′) ═CH ₂ . )
Represents a group represented by
R ¹ and R ² are each independently an optionally substituted aliphatic hydrocarbon group having 1 to 10 carbon atoms and an optionally substituted alicyclic carbon atom having 4 to 36 carbon atoms. A hydrogen group, an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent, or a heterocyclic group having 3 to 36 carbon atoms which may have a substituent.
X ¹ represents a C1-36 divalent hydrocarbon group which may have a substituent, and —CH ₂ — contained in the hydrocarbon group is —O—, —SO ₂ — or -CO- may be substituted. ^{Two of} R ¹ , R ² and X ¹ may be taken together to form a ring containing a sulfur atom. ]

Examples of the aliphatic hydrocarbon group having 1 to 10 carbon atoms of R ¹ and R ² include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, and a tert-butyl group. , A pentyl group, a hexyl group, an octyl group, a decyl group and a 2-ethylhexyl group.
Examples of the substituent that the aliphatic hydrocarbon group may have include an alicyclic hydrocarbon group having 3 to 12 carbon atoms, a hydroxy group, an alkoxy group having 1 to 8 carbon atoms, and an acyl having 1 to 8 carbon atoms. Group, an alkoxycarbonyl group having 2 to 9 carbon atoms, an acyloxy group having 2 to 8 carbon atoms, and the like.

The alicyclic hydrocarbon group having 4 to 36 carbon atoms may be monocyclic or polycyclic. Examples of the monocyclic aliphatic hydrocarbon group include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a perfluorocyclohexyl group. Examples of the group containing a polycyclic aliphatic hydrocarbon group include an adamantyl group and a norbornyl group.
Examples of the substituent that the alicyclic hydrocarbon group may have include an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a hydroxy group, an alkoxy group having 1 to 8 carbon atoms, and an acyl having 1 to 8 carbon atoms. Group, an alkoxycarbonyl group having 2 to 9 carbon atoms, an acyloxy group having 2 to 8 carbon atoms, and the like.

Examples of the aromatic hydrocarbon group having 6 to 36 carbon atoms include phenyl group, naphthyl group, anthryl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, and mesityl group. , Aryl groups such as biphenyl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl, and the like.
Examples of the substituent that the aromatic hydrocarbon group may have include a hydroxy group, a halogen atom, a cyano group, a nitro group, a carboxy group, an alkoxy group having 1 to 8 carbon atoms, an aryloxy group, and 1 to 1 carbon atoms. 8 acyl group, C2-C8 acyloxy group, C2-C9 alkoxycarbonyl group, C2-C9 alkoxycarbonyloxy group, amino group, C1-C8 acylamino group, C2 ˜9 alkoxycarbonylamino group, aryloxycarbonyl group and the like.
Among these, Preferably, a hydroxyl group, a halogen atom, a C1-C8 alkoxy group, and a C1-C8 acyl group are mentioned.

Examples of the acyl group include formyl group, acetyl group, propionyl group, butyryl group and the like.
Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, and an octyloxy group.

該複素環基が有していてもよい置換基としては、炭素数１〜１２の脂肪族炭化水素基などが挙げられる。 Examples of the heterocyclic group having 3 to 36 carbon atoms include groups represented by the following formulas.

Examples of the substituent that the heterocyclic group may have include an aliphatic hydrocarbon group having 1 to 12 carbon atoms.

Examples of the divalent hydrocarbon group for X ¹ include a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a divalent combination of two or more thereof. The group of is mentioned.
Examples of the divalent aliphatic hydrocarbon group include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, and a pentane-1, 5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, Butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4- Examples include alkanediyl groups such as diyl group, ethane-1,1-diyl group, propane-1,1-diyl group and propane-2,2-diyl group.

Examples of the divalent alicyclic hydrocarbon group include groups represented by formulas (Y1 ′) to (Y11 ′). Examples of the group in which —CH ₂ — contained in the alicyclic hydrocarbon group is replaced by —O—, —SO ₂ — or —CO— include, for example, formula (Y12 ′) to formula (Y26 ′). The group represented by these is mentioned.

  The divalent alicyclic hydrocarbon group is preferably a group represented by any of the formulas (Y1 ′) to (Y19 ′), more preferably the formula (Y11 ′), the formula (Y14 ′), A group represented by the formula (Y15 ′) or the formula (Y19 ′), more preferably a group represented by the formula (Y11 ′) or the formula (Y14 ′).

  Examples of the divalent aromatic hydrocarbon group include a phenylene group, a naphthalenediyl group, and an anthracenediyl group.

Examples of the substituent that the divalent hydrocarbon group represented by X ¹ may have include a halogen atom, a hydroxy group, and a nitro group.

  Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

（式（Ｉｙ）中、Ｒ’は、水素原子、フッ素原子を有してもよい炭素数１〜６のアルキル基、ヒドロキシ基又はシアノ基を表す。
Ｘ’は、単結合、−Ｏ−、＊−ＣＯ−Ｏ−、＊−Ａｒ−Ｏ−、＊−Ａｒ−ＣＯ−Ｏ−、＊−ＣＯ−Ｏ−Ａｒ−Ｏ−又は＊−ＣＯ−Ｏ−Ａｒ−ＣＯ−Ｏ−を表す。
Ａｒは、フェニレン基を表す。
＊は、−Ｃ（Ｒ’）＝ＣＨ_２との結合手を表す。） Y ¹ is a group represented by the formula (Iy).

(In formula (Iy), R ′ represents a hydrogen atom, a C 1-6 alkyl group which may have a fluorine atom, a hydroxy group or a cyano group.
X ′ represents a single bond, —O—, * —CO—O—, * —Ar—O—, * —Ar—CO—O—, * —CO—O—Ar—O— or * —CO—O. -Ar-CO-O- is represented.
Ar represents a phenylene group.
* Represents a bond with —C (R ′) ═CH ₂ . )

Examples of the alkyl group which may have a fluorine atom having 1 to 6 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, Alkyl groups such as a pentyl group and a hexyl group;
Difluoromethyl group, trifluoromethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, perfluoroethyl group, 1,1,2,2-tetrafluoro Propyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1- (trifluoromethyl) -1,2,2,2-tetrafluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group Perfluorobutyl group, 1,1-bis (trifluoro) methyl-2,2,2-trifluoroethyl group, 2- (perfluoropropyl) ethyl group, 1,1,2,2,3,3,4 4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3,4,4,5,5-decafluoropentyl group, 1,1-bis (trifluoromethyl) -2,2 , 3,3,3-pentafluoropropyl group, perfluoropentyl group, 2- (perfluorobutyl) ethyl group, 1,1,2,2,3,3,4,4,5,5-decafluorohexyl group, Examples thereof include fluorinated alkyl groups such as 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl group, perfluoropentylmethyl group and perfluorohexyl group.

R ′ is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or a methyl group.
X ′ is preferably * —CO—O—.

Examples of the ring formed by combining ^{two of} R ¹ , R ² and X ¹ include a heterocyclic ring containing at least one sulfur atom. Examples thereof include a ring represented by the following formula.

Among these, R ¹ and R ² are preferably an alicyclic hydrocarbon group or an aromatic hydrocarbon group, and more preferably an aromatic hydrocarbon group.
X ¹ is preferably a C6-C36 divalent hydrocarbon group containing an aromatic hydrocarbon group, and more preferably a C6-C36 divalent aromatic hydrocarbon group.

［式（Ｉｃ−ｚ２）中、
Ｐ^２２、Ｐ^２３及びＰ^２４は、互いに独立に、ヒドロキシ基、ハロゲン原子、シアノ基、ニトロ基、カルボキシ基、炭素数１〜１２の脂肪族炭化水素基、炭素数１〜８のアルコキシ基、アリールオキシ基、炭素数１〜８のアシル基、炭素数２〜８のアシルオキシ基、炭素数２〜９のアルコキシカルボニル基、炭素数２〜９のアルコキシカルボニルオキシ基、アミノ基、炭素数１〜８のアシルアミノ基、炭素数２〜９のアルコキシカルボニルアミノ基、炭素数７〜１８のアリールオキシカルボニル基を表すか、隣接する２つが一緒になって、硫黄原子を含む環を形成していてもよい。
ｘ２２及びｘ２４は、０〜５の整数を表す。
ｘ２３は、０〜４の整数を表す。
ｘ２２が２以上のとき、複数のＰ^２２は同一又は相異なり、ｘ２３が２以上のとき、複数のＰ^２３は同一又は相異なり、ｘ２４が２以上のとき、複数のＰ^２４は同一又は相異なる。
Ｙ^１は、上記と同じ意味を表す。］ The cation represented by the formula (Ic) is more preferably a cation represented by the formula (Ic-z2).

[In the formula (Ic-z2),
P ²² , P ²³ and P ²⁴ are each independently a hydroxy group, a halogen atom, a cyano group, a nitro group, a carboxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, Aryloxy group, C1-C8 acyl group, C2-C8 acyloxy group, C2-C9 alkoxycarbonyl group, C2-C9 alkoxycarbonyloxy group, amino group, C1-C1 8 represents an acylamino group, an alkoxycarbonylamino group having 2 to 9 carbon atoms, an aryloxycarbonyl group having 7 to 18 carbon atoms, or two adjacent groups together form a ring containing a sulfur atom Good.
x22 and x24 represent an integer of 0 to 5.
x23 represents an integer of 0 to 4.
When x22 is 2 or more, a plurality of ^{P 22} are the same or different, when x23 is 2 or more, a plurality of ^{P 23} are the same or different, when x24 is 2 or more, a plurality of ^{P 24} are same or different .
Y ¹ represents the same meaning as described above. ]

P ²² , P ²³ and P ²⁴ are preferably a hydroxy group, a halogen atom, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or an acyl group having 1 to 8 carbon atoms.

Examples of the ring containing a sulfur atom formed by combining two adjacent groups include a ring represented by the following formula.

Specific examples of the cation represented by the formula (Ic-z2) include the following. In the formula, Y ¹ represents the same meaning as described above.

Examples of the cation represented by the formula (Ic) include the followings.

Examples of the salt (I) include the following salts.

この反応の溶媒としては、クロロホルム等が挙げられる。 The salt represented by the formula (I1) which is the salt (IA) when Y ¹ and Y ² are methacryloyloxy groups includes, for example, a salt represented by the formula (I1-a) and a formula (I1-b ) Can be produced by reacting in a solvent. In the following description, each symbol has the same meaning as described above.

Examples of the solvent for this reaction include chloroform.

この塩基触媒としては、トリエチルアミン等が挙げられる。この反応の溶媒としては、クロロホルム等が挙げられる。 The salt represented by the formula (I1-a) is obtained by reacting the salt represented by the formula (I1-c) with the compound represented by the formula (I1-d) in a solvent under a base catalyst. Can be obtained.

Examples of the base catalyst include triethylamine. Examples of the solvent for this reaction include chloroform.

Examples of the salt represented by the formula (I1-c) include salts represented by the following, and can be easily obtained from the market.

The salt represented by the formula (I1-b) can be obtained according to Japanese Patent Application Laid-Open No. 2011-246439, and examples thereof include salts represented by the following.

<Resin>
The resin of the present invention (hereinafter sometimes referred to as “resin (A)”) contains a structural unit derived from salt (I) (hereinafter sometimes referred to as “structural unit (I)”). It is preferable that the resin of the present invention further contains a structural unit other than the structural unit (I). As such a structural unit, a structural unit having an acid labile group is sometimes referred to as “structural unit (a1)”, and a structural unit having no acid labile group is referred to as “structural unit (s)”. In some cases).
Resin (A) may contain 1 type of structural unit (I) independently, and may contain multiple types.

［式中、各符号はそれぞれ上記と同じ意味を表す。］ The structural unit (I) is represented by the following formula.

[Wherein each symbol represents the same meaning as described above. ]

［式（１）中、Ｒ^a1〜Ｒ^a3は、それぞれ独立に、炭素数１〜８のアルキル基、炭素数３〜２０の脂環式炭化水素基又はこれらを組合わせた基を表すか、Ｒ^a1及びＲ^a2は互いに結合して炭素数２〜２０の２価の炭化水素基を形成する。＊は結合手を表す。］

［式（２）中、Ｒ^a1’及びＲ^a2’は、それぞれ独立に、水素原子又は炭素数１〜１２の炭化水素基を表し、Ｒ^a3’は、炭素数１〜２０の炭化水素基を表すか、Ｒ^a2’及びＲ^a3’は互いに結合して炭素数２〜２０の２価の炭化水素基を形成し、該炭化水素基及び該２価の炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−Ｓ−で置き換わってもよい。＊は結合手を表す。］ <Structural unit (a1)>
The structural unit (a1) is derived from a monomer having an acid labile group (hereinafter sometimes referred to as “monomer (a1)”).
The “acid labile group” means a group having a leaving group and forming a hydrophilic group (for example, a hydroxy group or a carboxy group) by leaving the leaving group by contact with an acid. Examples of the acid labile group include a group represented by the formula (1) (hereinafter sometimes referred to as “group (1)”) and a group represented by the formula (2) (hereinafter referred to as “group (2)”). In some cases).

[In Formula (1), R ^<a1 > -R < ^a3 > respectively independently represents a C1-C8 alkyl group, a C3-C20 alicyclic hydrocarbon group, or the group which combined these, R ^a1 and R ^a2 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms. * Represents a bond. ]

[In Formula (2), R ^{a1 ′} and R ^{a2 ′} each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R ^{a3 ′} represents a hydrocarbon group having 1 to 20 carbon atoms. R ^{a2 ′} and R ^{a3 ′} are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms, and —CH ₂ — contained in the hydrocarbon group and the divalent hydrocarbon group. May be replaced by -O- or -S-. * Represents a bond. ]

アルキル基と脂環式炭化水素基とを組合わせた基としては、例えば、メチルシクロヘキシル基、ジメチルシクロへキシル基、メチルノルボルニル基等が挙げられる。 ^Examples of the alkyl group represented by R ^{a1 to} R ^a3 include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.
The alicyclic hydrocarbon group for R ^{a1 to} R ^a3 may be monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* represents a bond). The alicyclic hydrocarbon group of R ^{a1 to} R ^a3 preferably has 3 to 16 carbon atoms.

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

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

Examples of the group (1) include a 1,1-dialkylalkoxycarbonyl group (in the formula (1), R ^{a1 to} R ^a3 are alkyl groups, preferably a tert-butoxycarbonyl group), 2-alkyladamantane- 2-yloxycarbonyl group (in formula (1), wherein R ^a1 , R ^a2 and a carbon atom form an adamantyl group and R ^a3 is an alkyl group) and 1- (adamantan-1-yl) -1- And an alkylalkoxycarbonyl group (in the formula (1), R ^a1 and R ^a2 are alkyl groups, and R ^a3 is an adamantyl group).

Examples of the hydrocarbon group of R ^{a1 ′ to} R ^{a3 ′} include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and the like.
Examples of the aliphatic hydrocarbon group include alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.
Examples of the alicyclic hydrocarbon group are the same as those described above.
Aromatic hydrocarbon groups include phenyl, naphthyl, anthryl, p-methylphenyl, p-tert-butylphenyl, p-adamantylphenyl, tolyl, xylyl, cumenyl, mesityl, biphenyl Groups, phenanthryl groups, 2,6-diethylphenyl groups, aryl groups such as 2-methyl-6-ethylphenyl, and the like.
When R ^{a2 ′} and R ^{a3 ′} combine to form a divalent hydrocarbon group, * —C (R ^{a1 ′} ) (R ^{a2 ′} ) (OR ^{a3 ′} ) is the following group (in the formula, * Represents a bond.) The divalent hydrocarbon group preferably has 3 to 12 carbon atoms.

In Formula (2), it is preferable that at least one of R ^{a1 ′} and R ^{a2 ′} is a hydrogen atom.
Specific examples of the group (2) include the following groups. * Represents a bond.

  The monomer (a1) is preferably a monomer having an acid labile group and an ethylenically unsaturated bond, more preferably a (meth) acrylic monomer having an acid labile group.

  Among the (meth) acrylic monomers having an acid labile group, those having an alicyclic hydrocarbon group having 5 to 20 carbon atoms are preferable. If the resin (A) having the structural unit (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved.

The structural unit derived from the (meth) acrylic monomer having the group (1) is preferably a structural unit represented by the formula (a1-0), a structural unit represented by the formula (a1-1) or the formula ( a structural unit represented by a1-2). These may be used alone or in combination of two or more. In this specification, the structural unit represented by formula (a1-0), the structural unit represented by formula (a1-1), and the structural unit represented by formula (a1-2) are each represented by structural unit (a1). -0), structural unit (a1-1) and structural unit (a1-2), a monomer for deriving structural unit (a1-0), a monomer for deriving structural unit (a1-1), and a structural unit (a1- The monomer that induces 2) may be referred to as monomer (a1-0), monomer (a1-1), and monomer (a1-2), respectively.
Especially, it is preferable that resin has a structural unit (a1-1) or a structural unit (a1-2).

［式（ａ１−０）中、
Ｌ^a01は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k01−ＣＯ−Ｏ−を表し、ｋ０１は１〜７の整数を表し、＊はカルボニル基との結合手を表す。
Ｒ^a01は、それぞれ独立に、水素原子又はメチル基を表す。
Ｒ^a02、Ｒ^a03及びＲ^a04は、それぞれ独立に、炭素数１〜８のアルキル基、炭素数３〜１８の脂環式炭化水素基又はこれらを組合わせた基を表す。］

[In the formula (a1-0),
L ^a01 represents an oxygen atom or ^* —O— (CH ₂ ) _k01 —CO—O—, k01 represents an integer of 1 to 7, and * represents a bond to a carbonyl group.
R ^a01 independently represents a hydrogen atom or a methyl group.
R ^a02 , R ^a03 and R ^a04 each independently ^represent an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a group obtained by combining these. ]

［式（ａ１−１）中、
Ｌ^a1は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_h1−ＣＯ−Ｏ−を表し、ｈ１は１〜７の整数を表し、＊はカルボニル基との結合手を表す。
Ｒ^a4は、水素原子又はメチル基を表す。
Ｒ^a6は、炭素数１〜８のアルキル基、炭素数３〜１８の脂環式炭化水素基又はこれらを組合わせた基を表す。
ｍ１は、０〜１４の整数を表す。］

[In the formula (a1-1),
L ^a1 represents an oxygen atom or ^* —O— (CH ₂ ) _h1 —CO—O—, h1 represents an integer of 1 to 7, and * represents a bond to a carbonyl group.
R ^a4 represents a hydrogen atom or a methyl group.
R ^a6 represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a group obtained by combining these.
m1 represents the integer of 0-14. ]

［式（ａ１−２）中、
Ｌ^a2は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_h2−ＣＯ−Ｏ−を表し、ｈ２は１〜７の整数を表し、＊はカルボニル基との結合手を表す。
Ｒ^a5は、水素原子又はメチル基を表す。
Ｒ^a7は、炭素数１〜８のアルキル基、炭素数３〜１８の脂環式炭化水素基又はこれらを組合わせた基を表す。
ｎ１は、０〜１０の整数を表す。
ｎ１’は、０〜３の整数を表す。］

[In the formula (a1-2),
L ^a2 represents an oxygen atom or ^* —O— (CH ₂ ) _h2 —CO—O—, h2 represents an integer of 1 to 7, and * represents a bond with a carbonyl group.
R ^a5 represents a hydrogen atom or a methyl group.
R ^a7 represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a group obtained by combining these.
n1 represents the integer of 0-10.
n1 ′ represents an integer of 0 to 3. ]

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

h1 is preferably an integer of 1 to 4, more preferably 1.
L ^a1 is preferably an oxygen atom.
R ^a4 is preferably a methyl group.

h2 is preferably an integer of 1 to 4, more preferably 1.
L ^a2 is preferably an oxygen atom.
R ^a5 is preferably a methyl group.

アルキル基と脂環式炭化水素基とを組合わせた基としては、例えば、メチルシクロヘキシル基、ジメチルシクロへキシル基、メチルノルボルニル基等が挙げられる。 ^Examples of the alkyl group for R ^a6 and R ^a7 include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. The alkyl group preferably has 6 or less carbon atoms.
The alicyclic hydrocarbon group for R ^a6 and R ^a7 may be monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* represents a bond). The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms, more preferably 3 to 8 carbon atoms, and still more preferably 3 to 6 carbon atoms.

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

m1 is preferably an integer of 0 to 3, more preferably 0 or 1.
n1 is preferably an integer of 0 to 3, more preferably 0 or 1.
n1 ′ is preferably 0 or 1.

As the monomer (a1-0), for example, a monomer represented by any one of the formulas (a1-0-1) to (a1-0-12) is preferable, and the formula (a1-0-1) to the formula ( A monomer represented by any one of a1-0-10) is more preferable.

In the above structural unit, a structural unit in which a methyl group corresponding to R ^a01 is replaced with a hydrogen atom can also be given as a specific example of the structural unit (a1-0).

As a monomer (a1-1), the monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned, for example. Among these, a monomer represented by any one of formula (a1-1-1) to formula (a1-1-8) is preferable, and any one of formula (a1-1-1) to formula (a1-1-4) is preferable. The monomer represented by is more preferable.

Examples of the monomer (a1-2) include 1-ethylcyclopentan-1-yl (meth) acrylate, 1-ethylcyclohexane-1-yl (meth) acrylate, and 1-ethylcycloheptan-1-yl (meth). Acrylate, 1-methylcyclopentan-1-yl (meth) acrylate, 1-methylcyclohexane-1-yl (meth) acrylate, 1-isopropylcyclopentan-1-yl (meth) acrylate, 1-isopropylcyclohexane-1- Yl (meth) acrylate, 1-isopropylcycloheptan-1-yl (meth) acrylate, and the like. A monomer represented by any one of formula (a1-2-1) to formula (a1-2-12) is preferred, and formula (a1-2-3) to formula (a1-2-4) or formula (a1- The monomer represented by any one of 2-9) to formula (a1-2-10) is more preferred, and the monomer represented by formula (a1-2-3) or formula (a1-2-9) is more preferred. .

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

式（ａ１−３）中、
Ｒ^a13は、ヒドロキシ基を有していてもよい炭素数１〜３の脂肪族炭化水素基、カルボキシ基、シアノ基、水素原子又は−ＣＯＯＲ^aeを表す。
Ｒ^aeは、炭素数１〜８の脂肪族炭化水素基、炭素数３〜２０の脂環式炭化水素基、又はこれらを組み合わせた基を表し、該脂肪族炭化水素基及び該脂環式炭化水素基に含まれる水素原子は、ヒドロキシ基で置換されていてもよく、該脂肪族炭化水素基及び該脂環式炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基で置き換わっていてもよい。
Ｒ^a10、Ｒ^a11及びＲ^a12は、それぞれ独立に、炭素数１〜８のアルキル基、炭素数３〜２０の脂環式炭化水素基又はこれらを組合わせた基を表すか、Ｒ^a10及びＲ^a11は互いに結合して炭素数２〜２０の２価の炭化水素基を形成する。 Examples of the structural unit (a1) having the group (1) further include a structural unit represented by the formula (a1-3). In this specification, the structural unit represented by the formula (a1-3) may be referred to as the structural unit (a1-3) and the monomer that derives the structural unit (a1-3) may be referred to as a monomer (a1-3). is there.

In formula (a1-3),
R ^a13 represents an aliphatic hydrocarbon group having 1 to 3 carbon atoms which may have a hydroxy group, a carboxy group, a cyano group, a hydrogen atom, or —COOR ^ae .
R ^ae represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a combination thereof, and the aliphatic hydrocarbon group and the alicyclic carbon group. The hydrogen atom contained in the hydrogen group may be substituted with a hydroxy group, and the methylene group contained in the aliphatic hydrocarbon group and the alicyclic hydrocarbon group may be replaced with an oxygen atom or a carbonyl group. Good.
R ^a10, R ^a11 and R ^a12 are each independently an alkyl group having 1 to 8 carbon atoms, or an alicyclic hydrocarbon group or a group obtained by combining these C3-20, R ^a10 and R ^a11 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms.

Here, -COOR ^ae of R ^a13 includes, for example, a group in which a carbonyl group is bonded to an alkoxy group such as a methoxycarbonyl group and an ethoxycarbonyl group.

^Examples of the aliphatic hydrocarbon group which may have a hydroxyl group for R ^a13 include a methyl group, an ethyl group, a propyl group, a hydroxymethyl group and a 2-hydroxyethyl group.
Examples of the group consisting of R ^ae aliphatic hydrocarbon group, alicyclic hydrocarbon group, and aliphatic hydrocarbon group having 1 to 8 carbon atoms and alicyclic hydrocarbon group having 3 to 20 carbon atoms include, for example, methyl Group, ethyl group, propyl group, cyclopentyl group, cyclopropyl group, adamantyl group, adamantylmethyl group, 1-adamantyl-1-methylethyl group, 2-oxo-oxolan-3-yl group and 2-oxo-oxolane-4 -An yl group etc. are mentioned.
^{Examples of} R ^{a10 to} R ^a12 include the same groups as R ^{a1 to} R ^a3 in formula (1).
As —C (R ^a10 ) (R ^a11 ) (R ^a12 ) when R ^a10 and R ^a11 are bonded to each other to form a divalent hydrocarbon group, the following groups are preferred.

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

  Since the resin (A) containing the structural unit (a1-3) includes a sterically bulky structural unit, the resist composition of the present invention containing such a resin (A) is more expensive. A resist pattern can be obtained with resolution. Further, since a rigid norbornane ring is introduced into the main chain, the resulting resist pattern tends to be excellent in dry etching resistance.

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

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

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

^Examples of the alkyl group for R ^a32 and R ^a33 include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and further preferably a methyl group.
Examples of the halogen atom for R ^a32 and R ^a33 include a fluorine atom, a chlorine atom and a bromine atom.
Examples of the alkyl group having a halogen atom include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluorosec-butyl group, perfluorotert-butyl group, perfluoropentyl group, perfluorohexyl group, A trichloromethyl group, a tribromomethyl group, a triiodomethyl group, etc. are mentioned.
R ^a34, as the hydrocarbon group of R ^a35 and R ^a36, for example, aliphatic hydrocarbon group, alicyclic hydrocarbon group and aromatic hydrocarbon group., R ^{a1 'to} R ^a3 of formula (2) ^'include the same groups as.
Of these, the hydrocarbon group of R ^a34, R ^a35 and R ^a36, isopropyl group, n- butyl group, sec- butyl group, tert- butyl group, a pentyl group, a hexyl group, an octyl group, a 2-ethylhexyl group, A cyclohexyl group, an adamantyl group, a 2-alkyladamantan-2-yl group, a 1- (adamantan-1-yl) alkane-1-yl group, an isobornyl group, and the like are preferable.

In Formula (a1-2), R ^a32 is preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom.
R ^a33 is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and further preferably a methoxy group.
la is preferably 0 or 1, more preferably 0.
R ^a34 is preferably a hydrogen atom.
R ^a35 is preferably a hydrocarbon group having 1 to 12 carbon atoms, more preferably a methyl group or an ethyl group.
The hydrocarbon group for R ^a36 is preferably an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or these. A combined group, more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic aliphatic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms.

As a monomer which introduce | transduces structural unit (a1-4), the monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned, for example. Among these, monomers represented by formula (a1-4-1) to formula (a1-4-7) are preferable, and monomers represented by formula (a1-4-1) to formula (a1-4-5) are preferable. Is more preferable.

  When the resin (A) includes the structural unit (a1-4), the content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, based on all the structural units of the resin (A). 20 to 85 mol% is more preferable.

［式（ａ１−５）中、
Ｒ^a8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^ａ１は、単結合又は＊−（ＣＨ₂）_h3−ＣＯ−Ｌ^ａ６−を表し、ｈ３は１〜４の整数を表し、＊は、Ｌ^ａ１との結合手を表す。
Ｌ^ａ３、Ｌ^ａ４、Ｌ^ａ５及びＬ^ａ６は、それぞれ独立に、酸素原子又は硫黄原子を表す。
ｓ１は、１〜３の整数を表す。
ｓ１’は、０〜３の整数を表す。］ Examples of the structural unit (a1) having the group (2) include a structural unit represented by the formula (a1-5) (hereinafter sometimes referred to as “structural unit (a1-5)”).

[In the formula (a1-5),
R ^a8 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
Z ^a1 represents a single bond or * — (CH ₂ ) _h3 —CO—L ^a6 —, h3 represents an integer of 1 to 4, and * represents a bond to L ^a1 .
L ^a3 , L ^a4 , L ^a5 and L ^a6 each independently represent an oxygen atom or a sulfur atom.
s1 represents an integer of 1 to 3.
s1 ′ represents an integer of 0 to 3. ]

^Examples of R ^a8 include the same groups as R ^a32 in formula (a1-4).
R ^a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group.
L ^a5 is preferably an oxygen atom.
One of L ^a3 and L ^a4 is preferably an oxygen atom and the other is a sulfur atom.
s1 is preferably 1.
s1 ′ is preferably an integer of 0 to 2.
Z ^a1 is preferably a single bond or * —CH ₂ —CO—O—.

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

  When the resin (A) contains the structural unit (a1-5), the content is preferably 1 to 35 mol%, more preferably 1 to 30% with respect to all the structural units of the resin (A). Mol%.

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

<Structural unit without acid labile group>
The structural unit (s) is derived from a monomer having no acid labile group (hereinafter sometimes referred to as “monomer (s)”). The monomer for deriving the structural unit (s) (hereinafter sometimes referred to as “monomer (s)”) is not particularly limited as long as it does not have an acid labile group, and monomers known in the resist field can be used.
As the structural unit (s), a structural unit having a hydroxy group or a lactone ring and having no acid labile group is preferable. A structure having a hydroxy group and having no acid labile group (hereinafter sometimes referred to as “structural unit (a2)”) and / or a lactone ring and having no acid labile group If a resin having a unit (hereinafter sometimes referred to as “structural unit (a3)”) is used in the resist composition of the present invention, the resolution of the resist pattern and the adhesion to the substrate can be improved.

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

［式（ａ２−０）中、
Ｒ^a30は、水素原子、ハロゲン原子又はハロゲン原子を有してもよい炭素数１〜６のアルキル基を表す。
Ｒ^a31は、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数２〜４のアシル基、炭素数２〜４のアシルオキシ基、アクリロイルオキシ基又はメタクリロイルオキシ基を表す。
ｍａは０〜４の整数を表す。ｍａが２以上の整数である場合、複数のＲ^a31は同一又は相異なる。］ Examples of the structural unit (a2) having a phenolic hydroxy group include a structural unit represented by the formula (a2-0) (hereinafter sometimes referred to as “structural unit (a2-0)”).

[In the formula (a2-0),
R ^a30 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.
R ^a31 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or Represents a methacryloyloxy group.
ma represents an integer of 0 to 4. When ma is an integer of 2 or more, the plurality of R ^a31 are the same or different. ]

The R ^a30, include the same groups as R ^a32 of formula (a1-4). Among them, R ^a30 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.
The alkoxy group of R ^a31 is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and further preferably a methoxy group.
ma is preferably 0, 1 or 2, more preferably 0 or 1, and particularly preferably 0.

Examples of the monomer that derives the structural unit (a2-0) include monomers described in JP 2010-204634 A.
Among them, the structural unit (a2-0) is represented by formula (a2-0-1), formula (a2-0-2), formula (a2-0-3), and formula (a2-0-4), respectively. What is represented is preferable, and what is represented by a formula (a2-0-1) or a formula (a2-0-2) is more preferable.

  Resin (A) containing the structural unit (a2-0) is polymerized using a monomer in which the phenolic hydroxy group of the monomer that derives the structural unit (a2-0) is protected with a protective group such as an acetyl group. And then deprotecting. However, when the deprotection treatment is performed, the acid labile group of the structural unit (a1) needs to be not significantly impaired.

  When the resin (A) has the structural unit (a2-0), the content is preferably from 5 to 95 mol%, more preferably from 10 to 80 mol%, based on all the structural units of the resin (A). 15-80 mol% is more preferable.

式（ａ２−１）中、
Ｌ^a3は、−Ｏ−又は^＊−Ｏ−（ＣＨ₂）_k2−ＣＯ−Ｏ−を表し、
ｋ２は１〜７の整数を表す。＊は−ＣＯ−との結合手を表す。
Ｒ^a14は、水素原子又はメチル基を表す。
Ｒ^a15及びＲ^a16は、それぞれ独立に、水素原子、メチル基又はヒドロキシ基を表す。
ｏ１は、０〜１０の整数を表す。 Examples of the structural unit (a2) having an alcoholic hydroxy group include a structural unit represented by the formula (a2-1) (hereinafter sometimes referred to as “structural unit (a2-1)”).

In formula (a2-1),
L ^a3 represents —O— or ^* —O— (CH ₂ ) _k2 —CO—O—,
k2 represents an integer of 1 to 7. * Represents a bond with -CO-.
R ^a14 represents a hydrogen atom or a methyl group.
R ^a15 and R ^a16 each independently represent a hydrogen atom, a methyl group or a hydroxy group.
o1 represents an integer of 0 to 10.

In the formula (a2-1), L ^a3 is preferably, -O -, - O- (CH 2) f1 -CO-O- and is (wherein f1 is an integer from 1 to 4), more preferably Is —O—.
R ^a14 is preferably a methyl group.
R ^a15 is preferably a hydrogen atom.
R ^a16 is preferably a hydrogen atom or a hydroxy group.
o1 is preferably an integer of 0 to 3, more preferably 0 or 1.

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

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

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

The structural unit (a3) is preferably a structural unit represented by the formula (a3-1), the formula (a3-2), the formula (a3-3) or the formula (a3-4). These 1 type may be used independently and may use 2 or more types together.

［式（ａ３−１）中、
Ｌ^a4は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k3−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）で表される基を表す。＊はカルボニル基との結合手を表す。
Ｒ^a18は、水素原子又はメチル基を表す。
Ｒ^a21は炭素数１〜４の脂肪族炭化水素基を表す。
ｐ１は０〜５の整数を表す。ｐ１が２以上のとき、複数のＲ^a21は互いに同一又は相異なる。
式（ａ３−２）中、
Ｌ^a5は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k3−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）で表される基を表す。＊はカルボニル基との結合手を表す。
Ｒ^a19は、水素原子又はメチル基を表す。
Ｒ^a22は、カルボキシ基、シアノ基又は炭素数１〜４の脂肪族炭化水素基を表す。
ｑ１は、０〜３の整数を表す。ｑ１が２以上のとき、複数のＲ^a22は互いに同一又は相異なる。
式（ａ３−３）中、
Ｌ^a6は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k3−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）で表される基を表す。＊はカルボニル基との結合手を表す。
Ｒ^a20は、水素原子又はメチル基を表す。
Ｒ^a23は、カルボキシ基、シアノ基又は炭素数１〜４の脂肪族炭化水素基を表す。
ｒ１は、０〜３の整数を表す。ｒ１が２以上のとき、複数のＲ^a23は互いに同一又は相異なる。
式（ａ３−４）中、
Ｒ^a24は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
Ｌ^a7は、単結合、^＊−Ｌ^a8−Ｏ−、^＊−Ｌ^a8−ＣＯ−Ｏ−、^＊−Ｌ^a8−ＣＯ−Ｏ−Ｌ^a9−ＣＯ−Ｏ−又は^＊−Ｌ^a8−Ｏ−ＣＯ−Ｌ^a9−Ｏ−を表す。
＊は−Ｏ−との結合手を表す。
Ｌ^a8及びＬ^a9は、それぞれ独立に、炭素数１〜６のアルカンジイル基を表す。］

[In the formula (a3-1),
L ^a4 represents an oxygen atom or a group represented by ^* —O— (CH ₂ ) _k3 —CO—O— (k3 represents an integer of 1 to 7). * Represents a bond with a carbonyl group.
R ^a18 represents a hydrogen atom or a methyl group.
R ^a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
p1 represents an integer of 0 to 5. When p1 is 2 or more, the plurality of R ^a21 are the same or different from each other.
In formula (a3-2),
L ^a5 represents an oxygen atom or a group represented by ^* —O— (CH ₂ ) _k3 —CO—O— (k3 represents an integer of 1 to 7). * Represents a bond with a carbonyl group.
R ^a19 represents a hydrogen atom or a methyl group.
R ^a22 represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
q1 represents an integer of 0 to 3. When q1 is 2 or more, the plurality of R ^a22 are the same or different from each other.
In formula (a3-3),
L ^a6 represents an oxygen atom or a group represented by ^* —O— (CH ₂ ) _k3 —CO—O— (k3 represents an integer of 1 to 7). * Represents a bond with a carbonyl group.
R ^a20 represents a hydrogen atom or a methyl group.
R ^a23 represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
r1 represents an integer of 0 to 3. When r1 is 2 or more, the plurality of R ^a23 are the same or different from each other.
In formula (a3-4),
R ^a24 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
L ^a7 is a single bond, ^* —L ^a8 —O—, ^* —L ^a8 —CO—O—, ^* —L ^a8 —CO—O—L ^a9 —CO—O— or ^* —L ^a8 —O—CO —L ^a9 —O— is represented.
* Represents a bond with -O-.
L ^a8 and L ^a9 each independently represent an alkanediyl group having 1 to 6 carbon atoms. ]

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

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

In the formula (a3-1) to the formula (a3-3), L ^{a4 to} L ^a6 are each independently preferably an oxygen atom or * —O— (CH ₂ ) in which k3 is an integer of 1 to 4. A group represented by _{k 3} —CO—O—, more preferably an oxygen atom and * —O—CH ₂ —CO—O—, still more preferably an oxygen atom.
R ^{a18 to} R ^a21 are preferably methyl groups.
R ^a22 and R ^a23 are each independently preferably a carboxy group, a cyano group or a methyl group.
p1, q1, and r1 are each independently preferably an integer of 0-2.

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

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

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

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

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

［式（ａ４−１）中、
Ｒ^a41は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
Ａ^a41は、置換基を有していてもよい炭素数１〜６のアルカンジイル基又は式（ａ−ｇ１）

〔式（ａ−ｇ１）中、
ｓは０又は１を表す。
Ａ^a42及びＡ^a44は、それぞれ独立に、置換基を有していてもよい炭素数１〜５の２価の脂肪族炭化水素基を表す。
Ａ^a43は、単結合又は置換基を有していてもよい炭素数１〜５の２価の脂肪族炭化水素基を表す。
Ｘ^a41及びＸ^a42は、それぞれ独立に、−Ｏ−、−ＣＯ−、−ＣＯ−Ｏ−又は−Ｏ−ＣＯ−を表す。
ただし、Ａ^a42、Ａ^a43及びＡ^a44の炭素数の合計は７以下である。〕
で表される基を表す。
Ｒ^a42は、置換基を有していてもよい炭素数１〜２０の炭化水素基を表し、該炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
ただし、Ａ^a41及びＲ^a42のうち少なくとも一方は、ハロゲン原子を有する基である。］ As a structural unit (a4), the structural unit represented by a formula (a4-1) is mentioned, for example.

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

[In the formula (a-g1),
s represents 0 or 1.
A ^a42 and A ^a44 each independently represent a ^C 1-5 divalent aliphatic hydrocarbon group which may have a substituent.
A ^a43 represents a ^C1-C5 divalent aliphatic hydrocarbon group which may have a single bond or a substituent.
X ^a41 and X ^a42 each independently represent —O—, —CO—, ^—CO —O— or —O—CO—.
However, the total number of carbon atoms of A ^a42 , A ^a43 and A ^a44 is 7 or less. ]
Represents a group represented by
R ^a42 represents an ^optionally substituted hydrocarbon group having 1 to 20 carbon atoms, and the methylene group contained in the hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
However, at least one of A ^a41 and R ^a42 is a group having a halogen atom. ]

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

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

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

As a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned, Preferably it is a fluorine atom.
The hydrocarbon group having a halogen atom is preferably a hydrocarbon group having a fluorine atom, more preferably an aliphatic hydrocarbon group having a fluorine atom, an alicyclic hydrocarbon group having a fluorine atom, or a combination thereof. It is a group.

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

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

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

［式（ａ−ｇ２）中、
Ａ^a46は、ハロゲン原子を有していてもよい炭素数１〜１７の２価の炭化水素基を表す。
Ｘ^a44は、カルボニルオキシ基又はオキシカルボニル基を表す。
Ａ^a47は、ハロゲン原子を有していてもよい炭素数１〜１７の１価の炭化水素基を表す。
ただし、Ａ^a46及びＡ^a47の炭素数の合計は１８以下であり、Ａ^a46及びＡ^a47のうち、少なくとも一方は、少なくとも１つのハロゲン原子を有する。］ When R ^a42 is a group having a halogen atom, R ^a42 is preferably a group represented by the formula (a-g2).

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

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

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

^As the alkanediyl group of ^Aa41 , a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group , A straight-chain alkanediyl group such as hexane-1,6-diyl group; 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2 -Branched alkanediyl groups such as a diyl group, 1-methylbutane-1,4-diyl group, 2-methylbutane-1,4-diyl group.
^Examples of the substituent in the alkanediyl group of A ^a41 include a halogen atom, a hydroxy group, and an alkoxy group having 1 to 6 carbon atoms.
A ^a41 is preferably an alkanediyl group having 1 to 4 carbon atoms, more preferably an alkanediyl group having 2 to 4 carbon atoms, and still more preferably an ethylene group.

In the group represented by the formula (a-g1) of A ^a41 (hereinafter sometimes referred to as “group (a-g1)”), A ^a44 is ^bonded to —O—CO—R ^a42 .
As the aliphatic hydrocarbon group for A ^a42 , A ^a43 and A ^{a44 in} the group (a-g1), a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane- Examples include alkanediyl groups such as 1,4-diyl group, 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, and 2-methylpropane-1,2-diyl group. . Examples of these substituents include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms.
s is preferably 0.

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

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

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

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

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

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

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

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

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

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

［式（ａ４−３）中、
Ｒ^ｆ11は、水素原子又はメチル基を表す。
Ａ^ｆ11は、炭素数１〜６のアルカンジイル基を表す。
Ａ^ｆ13は、フッ素原子を有していてもよい炭素数１〜１７の２価の脂肪族炭化水素基、フッ素原子を有していてもよい炭素数３〜１７の２価の脂環式炭化水素基又はこれらを組み合わせた２価の基を表す。
Ｘ^ｆ12は、カルボニルオキシ基又はオキシカルボニル基を表す。
Ａ^ｆ14は、フッ素原子を有していてもよい炭素数１〜１７の脂肪族炭化水素基、フッ素原子を有していてもよい炭素数３〜１７の脂環式炭化水素基又はこれらを組み合わせた基を表す。
ただし、Ａ^ｆ13及びＡ^ｆ14のうち少なくとも一方は、フッ素原子を有する基を表す。］

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

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

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

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

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

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

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

［式（ａ４−４）中、
Ｒ^f21は、水素原子又はメチル基を表す。
Ａ^f21は、−（ＣＨ_２）_ｊ１−、−（ＣＨ_２）_ｊ２−Ｏ−（ＣＨ_２）_ｊ３−又は−（ＣＨ_２）_ｊ４−ＣＯ−Ｏ−（ＣＨ_２）_ｊ５−を表す。
ｊ１〜ｊ５は、それぞれ独立に、１〜６の整数を表す。
Ｒ^f22は、フッ素原子を有する炭素数１〜１０の炭化水素基を表す。］ Examples of the structural unit (a4) include a structural unit represented by the formula (a4-4).

[In the formula (a4-4),
R ^f21 represents a hydrogen atom or a methyl group.
A ^f21 represents — (CH ₂ ) _j1 —, — (CH ₂ ) _j2 —O— (CH ₂ ) _j3 — or — (CH ₂ ) _j4 —CO—O— (CH ₂ ) _j5 —.
j1 to j5 each independently represents an integer of 1 to 6.
R ^f22 represents a C 1-10 hydrocarbon group having a fluorine atom. ]

^Examples of the hydrocarbon group having a fluorine atom of R ^f22 include the same hydrocarbon groups as R ^f2 in formula (a4-2).

In Formula (a4-4), as A ^f21 , — (CH ₂ ) _j1 — is preferable, an ethylene group or a methylene group is more preferable, and a methylene group is further preferable.
R ^f22 is preferably a ^C 1-10 aliphatic hydrocarbon group having a fluorine atom or a C 1-10 alicyclic hydrocarbon group having a fluorine atom, and a C 1-10 aliphatic having a fluorine atom. An aromatic saturated hydrocarbon group is more preferable, and an aliphatic saturated hydrocarbon group having 1 to 6 carbon atoms having a fluorine atom is more preferable.

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

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

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

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

L ² is preferably a methylene group or an ethylene group, and more preferably a methylene group.
L ³ is preferably a C 1-6 perfluoroalkanediyl group, and more preferably a C ^1-3 C perfluoroalkanediyl group.

Examples of the structural unit (a4-0) include the following.

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

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

［式（ａ５−１）中、
Ｒ⁵¹は、水素原子又はメチル基を表す。
Ｒ⁵²は、炭素数３〜１８の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれる水素原子は炭素数１〜８の脂肪族炭化水素基又はヒドロキシ基で置換されていてもよい。但し、Ｌ⁵¹との結合位置にある炭素原子に結合する水素原子は、炭素数１〜８の脂肪族炭化水素基で置換されない。
Ｌ⁵¹は、単結合又は炭素数１〜１８の２価の飽和炭化水素基を表し、該飽和炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。］ <Structural unit (a5)>
Examples of the non-leaving hydrocarbon group that the structural unit (a5) has include a linear, branched, or cyclic hydrocarbon group. Especially, it is preferable that a structural unit (a5) is an alicyclic hydrocarbon group.
As a structural unit (a5), the structural unit represented by a formula (a5-1) is mentioned, for example.

[In the formula (a5-1),
R ⁵¹ represents a hydrogen atom or a methyl group.
R ⁵² represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and a hydrogen atom contained in the alicyclic hydrocarbon group is substituted with an aliphatic hydrocarbon group or hydroxy group having 1 to 8 carbon atoms. May be. However, the hydrogen atom bonded to the carbon atom at the bonding position with L ⁵¹ is not substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms.
L ⁵¹ represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and the methylene group contained in the saturated hydrocarbon group may be replaced with an oxygen atom or a carbonyl group. ]

The alicyclic hydrocarbon group for R ⁵² may be monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include an adamantyl group and a norbornyl group.
Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, Examples thereof include alkyl groups such as octyl group and 2-ethylhexyl group.
Examples of the alicyclic hydrocarbon group having a substituent include a 3-hydroxyadamantyl group and a 3-methyladamantyl group.
R ⁵² is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, and more preferably an adamantyl group, a norbornyl group, or a cyclohexyl group.

Examples of the divalent saturated hydrocarbon group for L ⁵¹ include a divalent aliphatic saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, preferably a divalent aliphatic saturated hydrocarbon group. .
Examples of the divalent aliphatic saturated hydrocarbon group include alkanediyl groups such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group, and a pentanediyl group.
The divalent alicyclic saturated hydrocarbon group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic saturated hydrocarbon group include cycloalkanediyl groups such as cyclopentanediyl group and cyclohexanediyl group. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include an adamantanediyl group and a norbornanediyl group.

式（Ｌ１−１）中、
Ｘ^x1は、カルボニルオキシ基又はオキシカルボニル基を表す。
Ｌ^x1は、炭素数１〜１６の２価の脂肪族飽和炭化水素基を表す。
Ｌ^x2は、単結合又は炭素数１〜１５の２価の脂肪族飽和炭化水素基を表す。
ただし、Ｌ^x1及びＬ^x2の合計炭素数は、１６以下である。
式（Ｌ１−２）中、
Ｌ^x3は、炭素数１〜１７の２価の脂肪族飽和炭化水素基を表す。
Ｌ^x4は、単結合又は炭素数１〜１６の２価の脂肪族飽和炭化水素基を表す。
ただし、Ｌ^x1及びＬ^x2の合計炭素数は、１７以下である。
式（Ｌ１−３）中、
Ｌ^x5は、炭素数１〜１５の２価の脂肪族飽和炭化水素基を表す。
Ｌ^x6及びＬ^x７は、それぞれ独立に、単結合又は炭素数１〜１４の２価の脂肪族飽和炭化水素基を表す。
ただし、Ｌ^x5、Ｌ^x6及びＬ^x7の合計炭素数は、１５以下である。
式（Ｌ１−４）中、
Ｌ^x8及びＬ^x9は、単結合又は炭素数１〜１２の２価の脂肪族飽和炭化水素基を表す。
Ｗ^x1は、炭素数３〜１５の２価の脂環式飽和炭化水素基を表す。
ただし、Ｌ^x8、Ｌ^x9及びＷ^x1の合計炭素数は、１５以下である。 Examples of the group in which the methylene group contained in the saturated hydrocarbon group is replaced with an oxygen atom or a carbonyl group include groups represented by formulas (L1-1) to (L1-4). In the following formula, * represents a bond with an oxygen atom.

In formula (L1-1),
X ^x1 represents a carbonyloxy group or an oxycarbonyl group.
L ^x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms.
L ^x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms.
However, the total carbon number of L ^x1 and L ^x2 is 16 or less.
In formula (L1-2),
L ^x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms.
L ^x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms.
However, the total carbon number of L ^x1 and L ^x2 is 17 or less.
In formula (L1-3),
L ^x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^x6 and L ^x7 each independently represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms.
However, the total carbon number of L ^x5 , L ^x6 and L ^x7 is 15 or less.
In formula (L1-4),
L ^x8 and L ^x9 represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms.
W ^x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms.
However, the total carbon number of L ^x8 , L ^x9 and W ^x1 is 15 or less.

L ^x1 is preferably a C 1-8 divalent aliphatic saturated hydrocarbon group, more preferably a methylene group or an ethylene group.
L ^x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond.
L ^x3 is preferably a C 1-8 divalent aliphatic saturated hydrocarbon group.
L ^x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group.
L ^x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group.
L ^x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms.
L ^x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group.
L ^x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group.
W ^x1 is preferably a C 3-10 divalent alicyclic saturated hydrocarbon group, more preferably a cyclohexanediyl group or an adamantanediyl group.

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

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

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

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

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

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

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

  When the resin (A) has the structural unit (a5), the content is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, based on all structural units of the resin (A). More preferably, it is 10 mol%.

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

The resin (A) is preferably a resin containing the structural unit (I) and the structural unit (a1), more preferably from the structural unit (I), the structural unit (a1), and the structural unit (s). Resin, that is, a copolymer of the salt (I), the monomer (a1) and the monomer (s).
The structural unit (a1) is preferably a structural unit (a1-0), a structural unit (a1-1), a structural unit (a1-2) (preferably the structural unit having a cyclohexyl group or a cyclopentyl group) and a structural unit. At least one of (a1-5), more preferably the structural unit (a1-1), the structural unit (a1-2), or the structural unit (a1-5).
The structural unit (s) is preferably at least one of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably a structural unit represented by the formula (a2-1). The structural unit (a3) is preferably at least one of a structural unit represented by the formula (a3-1) and a structural unit represented by the formula (a3-2).

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

When the resin (A) is a resin composed of the structural unit (I), the structural unit (a1), and the structural unit (s), these contents are respectively relative to all the structural units of the resin (A).
Structural unit (I); 1-60 mol%
Structural unit (a1); 15 to 74 mol%
Structural unit (s); 25-84 mol%
Is preferred,
Structural unit (I); 2 to 50 mol%
Structural unit (a1); 25-73 mol%
Structural unit (s); 25-73 mol%
Is more preferred,
Structural unit (I); 3 to 40 mol%
Structural unit (a1); 30 to 67 mol%
Structural unit (s); 30-67 mol%
Is more preferable.

Each structural unit constituting the resin (A) may be used alone or in combination of two or more, and is produced by a known polymerization method (for example, radical polymerization method) using a monomer that derives these structural units. can do. The content rate of each structural unit which resin (A) has can be adjusted with the usage-amount of the monomer used for superposition | polymerization.
The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,200 or more, further preferably 2,300 or more, more preferably 2,500 or more), 50,000 or less (more Preferably it is 30,000 or less, more preferably 15,000 or less, and still more preferably 10,000 or less.

<Resist composition>
The resist composition of the present invention contains salt (I), resin (A) or both.
The resist composition of the present invention preferably further contains a solvent (D).
The resist composition of the present invention preferably further contains a quencher (C).
The resist composition of the present invention may further contain an acid generator (B).
When the resist composition of the present invention contains the salt (I), the resist composition contains the structural unit (a1) and is a resin other than the resin (A) and / or the resin (A). It is preferable to contain.

<Resin other than resin (A)>
The resist composition of the present invention may contain a resin other than the resin (A). Such a resin may be any resin that does not have the structural unit (I). For example, a resin composed only of the structural unit (a1) and the structural unit (s), or a resin composed only of the structural unit (s). Is mentioned.

As the resin other than the resin (A), a resin composed only of the structural unit (a1) and the structural unit (s) (hereinafter sometimes referred to as “resin (A1)”) is preferable. In the resin (A1), the content of the structural unit (a1) is preferably 1 to 80 mol%, more preferably 1 to 75 mol%, and more preferably 3 to 70 mol% with respect to all the structural units of the resin (A1). Is more preferable.
The structural unit (a1) in the resin (A1) is preferably the structural unit (a1-0), the structural unit (a1-1), the structural unit (a1-2) (preferably the structure having a cyclohexyl group or a cyclopentyl group). Unit)) and structural unit (a1-5), more preferably structural unit (a1-1)), structural unit (a1-2) or structural unit (a1-5).
The structural unit (s) is preferably at least one of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably a structural unit represented by the formula (a2-1). The structural unit (a3) is preferably at least one of a structural unit represented by the formula (a3-1) and a structural unit represented by the formula (a3-2).
The weight average molecular weight of the resin (A1) is preferably 2,500 or more (more preferably 3,000 or more, more preferably 4,000 or more), 50,000 or less (more preferably 30,000 or less, and further preferably 15,000 or less).
When the resist composition of this invention contains resin (A1), the content rate becomes like this. Preferably it is 5-80 mass% with respect to the total amount of resin in the resist composition of this invention.
When the resist composition of the present invention contains the salt (I), the resin contained in the resist composition of the present invention may be only the resin (A1).

As the resin other than the resin (A), a resin having the structural unit (a4) (hereinafter sometimes referred to as “resin (X)”) is also preferable. In the resin (X), the content of the structural unit (a4) is preferably 50 mol% or more, more preferably 80 mol% or more, and still more preferably 85 mol% or more with respect to the total structural units of the resin (X). 90 mol% or more is even more preferable.
Examples of the structural unit that the resin (X) may further include a structural unit derived from the structural unit (a2), the structural unit (a3), the structural unit (a5), and other known monomers. .
The weight average molecular weight of the resin (X) is preferably 8,000 or more (more preferably 10,000 or more) and 80,000 or less (more preferably 60,000 or less). The means for measuring the weight average molecular weight of the resin (X) is the same as that for the resin (A).
When the resist composition of this invention contains resin (X), the content becomes like this. Preferably it is 1-60 mass parts with respect to 100 mass parts of resin (A), More preferably, it is 3-50 mass parts More preferably, it is 5-40 mass parts, Most preferably, it is 7-30 mass parts.

  In the resist composition of the present invention, the total solid content of the resist composition may be only the resin (A) or only the resin (A) and a resin other than the resin (A). The content of the resin [total of resin (A) and resin other than resin (A)] in the product is preferably 80% by mass or more and 99% by mass or less with respect to the solid content of the resist composition. In the present specification, the “solid content of the resist composition” means the sum of components excluding the solvent (D) described later from the total amount of the resist composition of the present invention. The solid content of the resist composition and the resin content relative to the solid content can be measured, for example, by known analytical means such as liquid chromatography or gas chromatography.

<Acid generator>
In the resist composition of the present invention, the salt (I) and / or the resin (A) or both act as an acid generator, but the resist composition of the present invention comprises the salt (I) and the resin (A). It may further contain an acid generator other than (hereinafter referred to as “acid generator (B)” in some cases).
As the acid generator (B), a known acid generator can be used, and an ionic acid generator or a nonionic generator may be used, but an ionic acid generator is preferable. Examples of the ionic acid generator include an ionic acid generator composed of a combination of a sulfonate anion constituting the salt (I) and a cation other than the organic cation constituting the salt (I), and the salt (I). Examples include an ionic acid generator composed of a combination of an organic cation constituting the salt and an anion other than the sulfonate anion constituting the salt (I), and an ionic acid generator composed of a combination of a known cation and a known anion. .

As an acid generator (B), the salt represented by either of Formula (B1-1)-Formula (B1-24) is mentioned, for example. Among them, those containing an arylsulfonium cation are preferable. Formula (B1-1), Formula (B1-2), Formula (B1-3), Formula (B1-5), Formula (B1-6), Formula (B1-7) ), Formula (B1-11), Formula (B1-12), Formula (B1-13), Formula (B1-14), Formula (B1-21), and Formula (B1-22). A salt is more preferred.

When the resist composition of the present invention contains an acid generator (B), the content thereof is preferably 1 part by mass or more (more preferably 3 parts by mass or more), preferably 100 parts by mass with respect to the total amount of the resin. 30 parts by mass or less (more preferably 25 parts by mass or less).
In the resist composition of the present invention, the acid generator (B) may contain one kind alone or plural kinds.

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

  Examples of the solvent (D) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; ethyl lactate, butyl acetate, amyl acetate and pyruvic acid Examples include esters such as ethyl; ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone; cyclic esters such as γ-butyrolactone; A solvent (D) may contain individually by 1 type and may contain 2 or more types.

<Quencher (C)>
The quencher in the resist composition of the present invention may be any compound that has an acid diffusion suppressing action, that is, a compound that traps an acid generated from an acid generator upon exposure. In addition to this action, the quencher generates an acid itself. It may be a compound obtained. Examples of the quencher include basic nitrogen-containing organic compounds and weak acid salts.

Examples of basic nitrogen-containing organic compounds include amines and ammonium salts. Amines include aliphatic and aromatic amines; primary amines, secondary amines and tertiary amines.
Examples of the amine include compounds represented by any one of the formulas (C1) to (C8), and a compound represented by the formula (C1-1) is preferable.

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

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

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

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

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

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

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

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

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

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

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

  Examples of the compound represented by the formula (C1) include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N, N- Dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributylamine, tri Pentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyl Hexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonyl Amine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diamino-1,2- Examples include diphenylethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane, and preferably diisopropyl. Piruanirin. Particularly preferred include 2,6-diisopropylaniline.

Examples of the compound represented by the formula (C2) include piperazine.
Examples of the compound represented by the formula (C3) include morpholine.
Examples of the compound represented by the formula (C4) include piperidine and hindered amine compounds having a piperidine skeleton described in JP-A No. 11-52575.
Examples of the compound represented by the formula (C5) include 2,2′-methylenebisaniline.
Examples of the compound represented by the formula (C6) include imidazole and 4-methylimidazole.
Examples of the compound represented by the formula (C7) include pyridine and 4-methylpyridine.
Examples of the compound represented by the formula (C8) include 1,2-di (2-pyridyl) ethane, 1,2-di (4-pyridyl) ethane, 1,2-di (2-pyridyl) ethene, 1, 2-di (4-pyridyl) ethene, 1,3-di (4-pyridyl) propane, 1,2-di (4-pyridyloxy) ethane, di (2-pyridyl) ketone, 4,4′-dipyridyl sulfide 4,4′-dipyridyl disulfide, 2,2′-dipyridylamine, 2,2′-dipiconylamine, bipyridine and the like.

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

  Examples of weak acid salts include acids generated from the structural unit (I) and acids weaker than acids generated from the acid generator (B) contained in the resist composition of the present invention. Or a sulfonate, preferably a salt represented by the formula (C10) or the formula (C11).

［式（Ｃ１０）中、
Ｒ^Ｃ２１は、置換基を有していてもよい炭素数１〜１０の脂肪族炭化水素基、置換基を有してもよい炭素数４〜３６の脂環式炭化水素基、置換基を有していてもよい炭素数３〜３６の芳香族炭化水素基又は置換基を有していてもよい炭素数３〜３６の複素環基を表し、該脂肪族炭化水素基及び該脂環式炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
Ｚ６^＋は、有機カチオンを表す。］

[In the formula (C10),
R ^C21 has an optionally substituted aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alicyclic hydrocarbon group having 4 to 36 carbon atoms that may have a substituent, and a substituent. Represents an optionally substituted aromatic hydrocarbon group having 3 to 36 carbon atoms or an optionally substituted heterocyclic group having 3 to 36 carbon atoms, the aliphatic hydrocarbon group and the alicyclic carbonized group. The methylene group contained in the hydrogen group may be replaced with an oxygen atom or a carbonyl group.
Z6 ⁺ represents an organic cation. ]

［式（Ｃ１１）中、
Ｒ^Ｃ２２及びＲ^Ｃ２３は、互いに独立に、水素原子、炭素数１〜１２の脂肪族炭化水素基、炭素数３〜２０の脂環式飽和炭化水素基、炭素数６〜２０の芳香族炭化水素基又は炭素数７〜２１のアラルキル基を表し、該脂肪族炭化水素基、該脂環式飽和炭化水素基、該芳香族炭化水素基及びアラルキル基に含まれる水素原子は、ヒドロキシ基、シアノ基、フッ素原子、トリフルオロメチル基又はニトロ基で置換されていてもよく、該脂肪族炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよく、Ｒ^Ｃ２２及びＲ^Ｃ２３は一緒になってこれらが結合する窒素原子とともに炭素数４〜２０の環を形成してもよい。
Ｚ７^＋は、有機カチオンを表す。］

[In the formula (C11),
R ^C22 and R ^C23 are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or an aromatic hydrocarbon having 6 to 20 carbon atoms. A hydrogen atom contained in the aliphatic hydrocarbon group, the alicyclic saturated hydrocarbon group, the aromatic hydrocarbon group and the aralkyl group is a hydroxy group or a cyano group. , A fluorine atom, a trifluoromethyl group or a nitro group, the methylene group contained in the aliphatic hydrocarbon group may be replaced by an oxygen atom or a carbonyl group, and R ^C22 and R ^C23 are Together, the nitrogen atom to which they are bonded may form a ring having 4 to 20 carbon atoms.
Z7 ⁺ represents an organic cation. ]

［式（Ｃ９）中、
Ｑ^ｃ1及びＱ^ｃ2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。
Ｌ^ｃ３は、単結合又は炭素数１〜１７の２価の飽和炭化水素基を表し、該２価の飽和炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
Ｙ^Ｎは窒素原子を含む有機基を表す。
Ｚ５^＋は、有機カチオンを表す。］ Examples of the quencher include a sulfonate having a nitrogen atom, for example, a salt represented by the formula (C9).

[In the formula (C9),
Q ^c1 and Q ^c2 each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^c3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and the methylene group contained in the divalent saturated hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
Y ^N represents an organic group containing a nitrogen atom.
Z5 ⁺ represents an organic cation. ]

^Examples of Q ^c1 and Q ^c2 include the same groups as R ¹ and R ² in formula (I), and preferred examples are also the same.
Y ^N is preferably a heterocyclic group containing a nitrogen atom. Examples of the heterocyclic ring constituting the heterocyclic ring include an imidazole ring and a morpholine ring.

Examples of the saturated hydrocarbon group for L ^c3 include a linear alkanediyl group, a branched alkanediyl group, and a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and two or more of these groups are included. It may be a combination.
Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1 , 6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group , Dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1, Linear alkanediyl groups such as 17-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group and propane-2,2-diyl group;
1-methylbutane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1, Branched alkanediyl groups such as 4-diyl groups;
Monocyclic 2 which is a cycloalkanediyl group such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group Valent alicyclic saturated hydrocarbon group;
Polycyclic divalent alicyclic saturated hydrocarbon such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. Groups and the like.

式（ｃ９−１）〜式（ｃ９−７）中、
Ｌ^C4は、単結合又は炭素数１〜１５の２価の飽和炭化水素基を表す。
Ｌ^C5は、単結合又は炭素数１〜１２の２価の飽和炭化水素基を表す。
Ｌ^C6は、炭素数１〜１３の２価の飽和炭化水素基を表す。但しＬ^C5及びＬ^C6の合計炭素数の上限は１３である。
Ｌ^C7は、単結合又は炭素数１〜１４の２価の飽和炭化水素基を表す。
Ｌ^C8は、炭素数１〜１５の２価の飽和炭化水素基を表す。但しＬ^C7及びＬ^C8の合計炭素数の上限は１５である。
Ｌ^C9は、単結合又は炭素数１〜１５の２価の飽和炭化水素基を表す。
Ｌ^C10は、炭素数１〜１６の２価の飽和炭化水素基を表す。但しＬ^C9及びＬ^C10の合計炭素数の上限は１６である。
Ｌ^C11は、単結合又は炭素数１〜１３の２価の飽和炭化水素基を表す。
Ｌ^C12は、炭素数１〜１４の２価の飽和炭化水素基を表す。但しＬ^C11及びＬ^C12の合計炭素数の上限は１４である。
Ｌ^C13及びＬ^C14は、単結合又は炭素数１〜１１の２価の飽和炭化水素基を表す。
Ｌ^C15は、炭素数１〜１２の２価の飽和炭化水素基を表す。但しＬ^C13、Ｌ^C14及びＬ^C15の合計炭素数の上限は１２である。
Ｌ^C16及びＬ^C17は、それぞれ独立に、単結合又は炭素数１〜１３の２価の飽和炭化水素基を表す。
Ｌ^C18は、炭素数１〜１４の飽和炭化水素基を表す。但しＬ^C16、Ｌ^C17及びＬ^C18の合計炭素数の上限は１４である。 Examples of those in which the methylene group contained in the saturated hydrocarbon group of L ^C3 is replaced with an oxygen atom or a carbonyl group include groups represented by formulas (c9-1) to (c9-7), respectively. * Represents a bond with C (Q ^c1 ) (Q ^c2 ). The same applies to specific examples of the following formulas (c9-1) to (c9-7).

In formula (c9-1) to formula (c9-7),
L ^C4 represents a single bond or a divalent saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^C5 represents a single bond or a divalent saturated hydrocarbon group having 1 to 12 carbon atoms.
L ^C6 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms. However, the upper limit of the total carbon number of L ^C5 and L ^C6 is 13.
L ^C7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 14 carbon atoms.
L ^C8 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. However, the upper limit of the total carbon number of L ^C7 and L ^C8 is 15.
L ^C9 represents a single bond or a divalent saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^C10 represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms. However, the upper limit of the total carbon number of L ^C9 and L ^C10 is 16.
L ^C11 represents a single bond or a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.
L ^C12 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms. However, the upper limit of the total carbon number of L ^C11 and L ^C12 is 14.
L ^C13 and L ^C14 represent a single bond or a divalent saturated hydrocarbon group having 1 to 11 carbon atoms.
L ^C15 represents a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. However, the upper limit of the total carbon number of L ^C13 , L ^C14 and L ^C15 is 12.
L ^C16 and L ^C17 each independently represent a single bond or a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.
L ^C18 represents a saturated hydrocarbon group having 1 to 14 carbon atoms. However, the upper limit of the total carbon number of L ^C16 , L ^C17 and L ^C18 is 14.

L ^C3 is preferably a group represented by the formula (c9-1), and a group represented by the formula (c9-1) in which L ^C4 is a single bond or an aliphatic saturated hydrocarbon group having 1 to 6 carbon atoms. More preferred.

Examples of the group represented by the formula (c9-1) include the following.

Examples of the group represented by the formula (c9-2) include the following.

Examples of the group represented by the formula (c9-3) include the following.

Examples of the group represented by the formula (c9-4) include the following.

Examples of the group represented by the formula (c9-5) include the following.

Examples of the group represented by the formula (c9-6) include the following.

Examples of the group represented by the formula (c9-7) include the following.

Examples of organic cations of Z5 ⁺ , Z6 ⁺ and Z7 ⁺ include organic onium cations such as organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations, and preferably organic sulfoniums. A cation or an organic iodonium cation, more preferably a cation represented by any one of formulas (b2-1) to (b2-4).

In formula (b2-1) to formula (b2-4),
R ^{b4 to} R ^b6 each independently represents an aliphatic hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, The hydrogen atom contained in the aliphatic hydrocarbon group is a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. The hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an acyl group having 2 to 4 carbon atoms, or a glycidyloxy group. The hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group or an alkoxy group having 1 to 12 carbon atoms.
R ^b4 and R ^b5 may together form a ring containing a sulfur atom to which they are bonded, and —CH ₂ — contained in the ring is —O—, —SO— or —CO—. May be replaced.

R ^b7 and R ^b8 each independently represent a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
m2 and n2 each independently represent an integer of 0 to 5.
When m2 is 2 or more, the plurality of R ^b7 may be the same or different, and when n2 is 2 or more, the plurality of R ^b8 may be the same or different.

R ^b9 and R ^b10 each independently represent an aliphatic hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms.
R ^b9 and R ^b10 together may form a ring containing a sulfur atom to which they are bonded, and —CH ₂ — contained in the ring is —O—, —SO— or —CO—. May be replaced.
R ^b11 represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.
R ^b12 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and is included in the aliphatic hydrocarbon The hydrogen atom may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the aromatic hydrocarbon group is an alkoxy group having 1 to 12 carbon atoms or 1 to 1 carbon atoms. It may be substituted with 12 alkylcarbonyloxy groups.
R ^b11 and R ^b12 may together form a ring containing —CH—CO— to which they are bonded, and —CH ₂ — contained in the ring is —O—, —SO—. Alternatively, it may be replaced by -CO-.

R ^{b13 to} R ^b18 each independently represent a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
L ^b11 represents -S- or -O-.
o2, p2, s2, and t2 each independently represents an integer of 0 to 5.
q2 and r2 each independently represents an integer of 0 to 4.
u2 represents 0 or 1.
When o2 is 2 or more, multiple R ^b13 are the same or different, when p2 is 2 or more, multiple R ^b14 are the same or different, and when q2 is 2 or more, multiple R ^b15 are the same or different , When r2 is 2 or more, a plurality of R ^b16 are the same or different, when s2 is 2 or more, a plurality of R ^b17 are the same or different, and when t2 is 2 or more, a plurality of R ^b18 are the same or different Different.

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

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

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

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

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

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

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

Among these, a cation represented by the formula (b2-1) is preferable.
In the formula (b2-1), R ^{b4 to} R ^b6 each independently preferably represent an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the hydrogen atom contained in the aromatic hydrocarbon group is a halogen atom. It may be substituted with an atom, a hydroxy group or an alkoxy group having 1 to 12 carbon atoms.
Examples of such organic cations include cations described in JP 2010-204646 A.
The organic cation of Z5 ⁺ , Z6 ⁺ and Z7 ⁺ is particularly preferably a triphenylsulfonium cation, diphenyltolylsulfonium cation, tolylsulfonium cation or tris (tert-butylphenyl) sulfonium cation.

Examples of the salt represented by the formula (C9) include salts represented by the following formula and salts described in JP 2012-6908 A and JP 2012-72109 A.

Examples of the salt represented by the formula (C10) include a salt represented by the following and a salt described in JP2011-39502A.

As a salt represented by a formula (C11), the salt represented by the following and the salt of Unexamined-Japanese-Patent No. 2011-191745 are mentioned, for example.

  The content of the quencher (C) is preferably 0.01 to 5% by mass, more preferably 0.01 to 3% by mass, and particularly preferably 0.01 to 1% in the solid content of the resist composition. % By mass.

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

<Preparation of resist composition>
The resist composition of the present invention comprises a resin (A) and / or a salt (I), a resin other than the resin (A) used as necessary, a solvent (D), an acid generator (B), a basic It can be prepared by mixing the compound (C) and the other component (F). The mixing order is arbitrary and is not particularly limited. The temperature at the time of mixing can select an appropriate temperature range from the range of 10-40 degreeC according to the kind etc. of resin etc., the solubility with respect to solvents (D), such as resin. An appropriate mixing time can be selected from 0.5 to 24 hours depending on the mixing temperature. The mixing means is not particularly limited, and stirring and mixing can be used.
After mixing each component, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm.

<Method for producing resist pattern>
The method for producing a resist pattern of the present invention comprises:
(1) The process of apply | coating the resist composition of this invention on a board | substrate,
(2) The process of drying the composition after application | coating and forming a composition layer,
(3) a step of exposing the composition layer;
(4) The process of heating the composition layer after exposure, (5) The process of developing the composition layer after a heating is included.

  Application of the resist composition onto the substrate can be performed by a commonly used apparatus such as a spin coater. By adjusting the conditions of the coating apparatus, the film thickness of the composition after coating can be adjusted. Examples of the substrate include a silicon wafer. Before applying the resist composition, the substrate may be washed or an antireflection film may be formed using a commercially available organic antireflection film composition.

By drying the composition after coating, the solvent is removed and a composition layer is formed. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking), or using a decompression device. The heating temperature is preferably 50 to 200 ° C., for example, and the heating time is preferably 10 to 180 seconds, for example. The pressure during drying under reduced pressure is preferably about 1 to 1.0 × 10 ⁵ Pa.

The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. Exposure light sources include those that emit laser light in the ultraviolet region, such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F ₂ excimer laser (wavelength 157 nm), solid-state laser light source (YAG or semiconductor laser) Etc.) using various types of laser light such as those that convert wavelength of laser light from the laser and emit harmonic laser light in the far-ultraviolet region or vacuum ultraviolet region, those that irradiate electron beams, extreme ultraviolet light (EUV), etc. it can. In this specification, irradiating these radiations may be collectively referred to as “exposure”. The exposure is usually performed through a mask corresponding to a desired resist pattern. When the exposure light source is an electron beam, a desired pattern may be directly drawn without using a photomask.

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

  The heated composition layer is usually developed using a developer using a developing device. Examples of the developing method include a dipping method, a paddle method, a spray method, and a dynamic dispensing method. The development temperature is preferably 5 to 60 ° C., for example, and the development time is preferably 5 to 300 seconds, for example.

By selecting the type of developer, a positive resist pattern or a negative resist pattern can be produced.
When producing a positive resist pattern from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be various alkaline aqueous solutions used in this field. Examples thereof include an aqueous solution of tetramethylammonium hydroxide and (2-hydroxyethyl) trimethylammonium hydroxide (commonly called choline). The alkali developer may contain a surfactant.
It is preferable to wash the resist pattern with ultrapure water after development, and then remove the water remaining on the substrate and the pattern.

In the case of producing a negative resist pattern from the resist composition of the present invention, a developer containing an organic solvent as a developer (hereinafter sometimes referred to as “organic developer”) is used.
Organic solvents contained in the organic developer include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycols such as propylene glycol monomethyl ether Examples include ether solvents; amide solvents such as N, N-dimethylacetamide; aromatic hydrocarbon solvents such as anisole.
In the organic developer, the content of the organic solvent is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and still more preferably only the organic solvent.
Among them, the organic developer is preferably a developer containing butyl acetate and / or 2-heptanone. In the organic developer, the total content of butyl acetate and 2-heptanone is preferably 50% by mass to 100% by mass, more preferably 90% by mass to 100% by mass, and substantially butyl acetate and / or 2 -More preferred is heptanone alone.
The organic developer may contain a surfactant. The organic developer may contain a trace amount of water.
At the time of development, the development may be stopped by substituting a solvent of a different type from the organic developer.

It is preferable to wash the developed resist pattern with a rinse solution. The rinsing liquid is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, and an alcohol solvent or an ester solvent is preferable.
After the cleaning, it is preferable to remove the rinse solution remaining on the substrate and the pattern.

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

The present invention will be described more specifically with reference to examples. In the examples, “%” and “parts” representing the content or amount used are based on mass unless otherwise specified.
The structure of the compound was confirmed by MASS (LC: Agilent 1100 type, MASS: Agilent LC / MSD type or LC / MSD TOF type).
The weight average molecular weight is a value determined by gel permeation chromatography under the following conditions.
Apparatus: HLC-8120GPC type (manufactured by Tosoh Corporation)
Column: TSKgel Multipore HXL-M x 3 + guardcolumn (manufactured by Tosoh Corporation)
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min
Detector: RI detector Column temperature: 40 ° C
Injection volume: 100 μl
Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation)

式（Ｉ−２−１）で表される塩２０．００部、式（Ｉ−２−２）で表される化合物８．１０部及びクロロホルム２００部を仕込み、攪拌下、トリエチルアミン５．８０部を滴下し、２３℃で２時間攪拌した。得られた反応物に、イオン交換水８０部を添加、攪拌し、分液を行った。この水洗操作を５回行った。その後、回収された有機層を濃縮することにより、式（Ｉ−２−３）で表される塩２３．５８部を得た。 Example 1 [Synthesis of a salt represented by the formula (I-2)]

20.00 parts of the salt represented by the formula (I-2-1), 8.10 parts of the compound represented by the formula (I-2-2) and 200 parts of chloroform were charged, and 5.80 parts of triethylamine were stirred. Was added dropwise and stirred at 23 ° C. for 2 hours. To the obtained reaction product, 80 parts of ion-exchanged water was added and stirred to carry out liquid separation. This washing operation was performed 5 times. Thereafter, the recovered organic layer was concentrated to obtain 23.58 parts of the salt represented by the formula (I-2-3).

式（Ｉ−２−４）で表される塩２４．６１部及びクロロホルム１５０部を仕込み、攪拌下、式（Ｉ−２−３）で表される塩２０．９３部をクロロホルム１２部に溶解した溶液を添加した。得られた混合物に、イオン交換水５０部を添加し、２３℃で２時間攪拌した後、分液を行った。回収された有機層に、イオン交換水５０部を添加し、２３℃で３０分間攪拌した後、分液を行った。この水洗操作を５回行った。回収された有機層を濃縮することにより、式（Ｉ−２）で表される塩１７．６８部を得た。
ＭＡＳＳ（ＥＳＩ（＋）Ｓｐｅｃｔｒｕｍ）：Ｍ^＋ ３７５．１
ＭＡＳＳ（ＥＳＩ（−）Ｓｐｅｃｔｒｕｍ）：Ｍ⁻ ２７３．０

Charge 24.61 parts of the salt represented by the formula (I-2-4) and 150 parts of chloroform, and dissolve with stirring 20.93 parts of the salt represented by the formula (I-2-3) in 12 parts of chloroform. The solution was added. To the obtained mixture, 50 parts of ion-exchanged water was added and stirred at 23 ° C. for 2 hours, followed by liquid separation. To the recovered organic layer, 50 parts of ion-exchanged water was added and stirred at 23 ° C. for 30 minutes, followed by liquid separation. This washing operation was performed 5 times. The recovered organic layer was concentrated to obtain 17.68 parts of the salt represented by the formula (I-2).
MASS (ESI (+) Spectrum): M ⁺ 375.1
MASS (ESI (-) Spectrum): M ^- 273.0

式（Ｉ−１４−４）で表される塩２２．６８部及びクロロホルム１５０部を仕込み、攪拌下、式（Ｉ−２−３）で表される塩２０．９３部をクロロホルム１２部に溶解した溶液を添加した。得られた混合物に、イオン交換水５０部を添加し、２３℃で２時間攪拌した後、分液を行った。回収された有機層に、イオン交換水５０部を添加し、２３℃で３０分間攪拌した後、分液を行った。この水洗操作を５回行った。回収された有機層を濃縮することにより、式（Ｉ−１４）で表される塩１５．２２部を得た。
ＭＡＳＳ（ＥＳＩ（＋）Ｓｐｅｃｔｒｕｍ）：Ｍ^＋ ３７５．１
ＭＡＳＳ（ＥＳＩ（−）Ｓｐｅｃｔｒｕｍ）：Ｍ⁻ ２３１．０ Example 2 [Synthesis of salt represented by formula (I-14)]

Charge 22.68 parts of the salt represented by the formula (I-14-4) and 150 parts of chloroform, and dissolve with stirring 20.93 parts of the salt represented by the formula (I-2-3) in 12 parts of chloroform. The solution was added. To the obtained mixture, 50 parts of ion-exchanged water was added and stirred at 23 ° C. for 2 hours, followed by liquid separation. To the recovered organic layer, 50 parts of ion-exchanged water was added and stirred at 23 ° C. for 30 minutes, followed by liquid separation. This washing operation was performed 5 times. The recovered organic layer was concentrated to obtain 15.22 parts of the salt represented by the formula (I-14).
MASS (ESI (+) Spectrum): M ⁺ 375.1
MASS (ESI (−) Spectrum): M ^- 231.0

式（Ｉ−２２−４）で表される塩２５．８０部及びクロロホルム１５０部を仕込み、攪拌下、式（Ｉ−２−３）で表される塩２０．９３部をクロロホルム１２部に溶解した溶液を添加した。得られた混合物に、イオン交換水５０部を添加し、２３℃で２時間攪拌した後、分液を行った。回収された有機層に、イオン交換水５０部を添加し、２３℃で３０分間攪拌した後、分液を行った。この水洗操作を５回行った。回収された有機層を濃縮することにより、式（Ｉ−２２）で表される塩１９．９８部を得た。
ＭＡＳＳ（ＥＳＩ（＋）Ｓｐｅｃｔｒｕｍ）：Ｍ^＋ ３７５．１
ＭＡＳＳ（ＥＳＩ（−）Ｓｐｅｃｔｒｕｍ）：Ｍ⁻ ２９９．０ Example 3 [Synthesis of a salt represented by the formula (I-22)]

First, 25.80 parts of the salt represented by the formula (I-22-4) and 150 parts of chloroform were charged, and 20.93 parts of the salt represented by the formula (I-2-3) were dissolved in 12 parts of chloroform under stirring. The solution was added. To the obtained mixture, 50 parts of ion-exchanged water was added and stirred at 23 ° C. for 2 hours, followed by liquid separation. To the recovered organic layer, 50 parts of ion-exchanged water was added and stirred at 23 ° C. for 30 minutes, followed by liquid separation. This washing operation was performed 5 times. The recovered organic layer was concentrated to obtain 19.98 parts of the salt represented by the formula (I-22).
MASS (ESI (+) Spectrum): M ⁺ 375.1
MASS (ESI (−) Spectrum): M ^- 299.0

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

Example 4 [Synthesis of Resin A1]
As the monomer, monomer (a1-1-3), monomer (a1-2-7), monomer (a2-1-1), monomer (a3-2-3), monomer (a3-1-1) and monomer ( I-2) and its molar ratio [monomer (a1-1-3): monomer (a1-2-7): monomer (a2-1-1): monomer (a3-2-3): monomer (a3 -1-1): monomer (I-2)] is 28: 15: 5: 15: 32: 5, and 1.5 mass times the total monomer amount of ketyl ethyl ketone is added to the solution. did. As initiators, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added in an amount of 1.2 mol% and 3.6 mol%, respectively, based on the total amount of monomers, and heated at 75 ° C. for about 5 hours. . The obtained resin solution was poured into a large amount of a mixed solvent of methanol and water (mass ratio methanol: water = 4: 1) to precipitate the resin. This resin was filtered and collected. Again, it is dissolved in methyl ethyl ketone, poured into a large amount of methanol / water mixed solvent to precipitate the resin, and the precipitated resin is filtered and collected twice to perform reprecipitation purification, and the weight average molecular weight is 5 A copolymer of .6 × 10 ³ was obtained with a yield of 55%. This copolymer has the following structural units each derived from the above-mentioned monomers, and this is designated as resin A1.

Example 5 [Synthesis of Resin A2]
As the monomer, the monomer (a1-1-2), the monomer (a2-1-1), the monomer (a3-1-1) and the monomer (I-2) are used, and their molar ratio [monomer (a1-1-2) ): Monomer (a2-1-1): monomer (a3-1-1): monomer (I-2)] is 40: 25: 25: 10, and the total monomer amount is 1.5 mass. Double ketyl ethyl ketone was added to make 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. The obtained resin solution was poured into a large amount of a mixed solvent of methanol and water (mass ratio methanol: water = 4: 1) to precipitate the resin. This resin was filtered and collected. Again, it is dissolved in methyl ethyl ketone, poured into a large amount of methanol / water mixed solvent to precipitate the resin, and the precipitated resin is filtered and recovered twice to perform reprecipitation purification, and the weight average molecular weight is 6 A copolymer of .8 × 10 ³ was obtained with a yield of 60%. This copolymer has the following structural units each derived from the above-mentioned monomers, and this is designated as resin A2.

Example 6 [Synthesis of Resin A3]
As the monomer, monomer (a1-1-3), monomer (a1-5-1), monomer (a2-1-1), monomer (a3-2-3), monomer (a3-1-1) and monomer ( I-2) and its molar ratio [monomer (a1-1-3): monomer (a1-5-1): monomer (a2-1-1): monomer (a3-2-3): monomer (a3 -1-1): monomer (I-2)] is 28: 15: 5: 15: 32: 5, and 1.5 mass times the total monomer amount of ketyl ethyl ketone is added to the solution. did. As initiators, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added in an amount of 1.2 mol% and 3.6 mol%, respectively, based on the total amount of monomers, and heated at 75 ° C. for about 5 hours. . The obtained resin solution was poured into a large amount of a mixed solvent of methanol and water (mass ratio methanol: water = 4: 1) to precipitate the resin. This resin was filtered and collected. Again, it is dissolved in methyl ethyl ketone, poured into a large amount of methanol / water mixed solvent to precipitate the resin, and the precipitated resin is filtered and collected twice to perform reprecipitation purification, and the weight average molecular weight is 5 A copolymer of .9 × 10 ³ was obtained with a yield of 60%. This copolymer has the following structural units each derived from the above-mentioned monomers, and this is designated as resin A3.

Example 7 [Synthesis of Resin A4]
As the monomer, monomer (a1-1-3), monomer (a1-0-10), monomer (a2-1-1), monomer (a3-2-3), monomer (a3-1-1) and monomer ( I-2) and its molar ratio [monomer (a1-1-3): monomer (a1-0-10): monomer (a2-1-1): monomer (a3-2-3): monomer (a3 -1-1): monomer (I-2)] is 28: 15: 5: 15: 32: 5, and 1.5 mass times the total monomer amount of ketyl ethyl ketone is added to the solution. did. As initiators, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added in an amount of 1.2 mol% and 3.6 mol%, respectively, based on the total amount of monomers, and heated at 75 ° C. for about 5 hours. . The obtained resin solution was poured into a large amount of a mixed solvent of methanol and water (mass ratio methanol: water = 4: 1) to precipitate the resin. This resin was filtered and collected. Again, it is dissolved in methyl ethyl ketone, poured into a large amount of methanol / water mixed solvent to precipitate the resin, and the precipitated resin is filtered and recovered twice to perform reprecipitation purification, and the weight average molecular weight is 6 A copolymer of .6 × 10 ³ was obtained with a yield of 45%. This copolymer has the following structural units each derived from the above monomer, and is referred to as Resin A4.

Example 8 [Synthesis of Resin A5]
As the monomer, monomer (a1-1-3), monomer (a1-2-7), monomer (a2-1-1), monomer (a3-2-3), monomer (a3-1-1) and monomer ( 1-14), and its molar ratio [monomer (a1-1-3): monomer (a1-2-7): monomer (a2-1-1): monomer (a3-2-3): monomer (a3 -1-1): monomer (I-14)] is 28: 15: 5: 15: 32: 5, and 1.5 mass times the total monomer amount of ketyl ethyl ketone is added to the solution. did. As initiators, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added in an amount of 1.2 mol% and 3.6 mol%, respectively, based on the total amount of monomers, and heated at 75 ° C. for about 5 hours. . The obtained resin solution was poured into a large amount of a mixed solvent of methanol and water (mass ratio methanol: water = 4: 1) to precipitate the resin. This resin was filtered and collected. Again, it is dissolved in methyl ethyl ketone, poured into a large amount of methanol / water mixed solvent to precipitate the resin, and the precipitated resin is filtered and collected twice to perform reprecipitation purification, and the weight average molecular weight is 5 A copolymer of 9.9 × 10 ³ was obtained with a yield of 55%. This copolymer has the following structural units each derived from the above-mentioned monomers, and this is designated as resin A5.

Example 9 [Synthesis of Resin A6]
As the monomer, monomer (a1-1-3), monomer (a1-2-7), monomer (a2-1-1), monomer (a3-2-3), monomer (a3-1-1) and monomer ( I-22) and its molar ratio [monomer (a1-1-3): monomer (a1-2-7): monomer (a2-1-1): monomer (a3-2-3): monomer (a3 -1-1): monomer (I-22)] is 28: 15: 5: 15: 32: 5, and 1.5 mass times the total monomer amount of ketyl ethyl ketone is added to the solution. did. As initiators, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added in an amount of 1.2 mol% and 3.6 mol%, respectively, based on the total amount of monomers, and heated at 75 ° C. for about 5 hours. . The obtained resin solution was poured into a large amount of a mixed solvent of methanol and water (mass ratio methanol: water = 4: 1) to precipitate the resin. This resin was filtered and collected. Again, it is dissolved in methyl ethyl ketone, poured into a large amount of methanol / water mixed solvent to precipitate the resin, and the precipitated resin is filtered and recovered twice to perform reprecipitation purification, and the weight average molecular weight is 6 A copolymer of 3 × 10 ³ was obtained with a yield of 48%. This copolymer has the following structural units each derived from the above-mentioned monomers, and this is designated as resin A6.

Synthesis Example 1 [Synthesis of Resin H1]
Resin H1 having the following structural units was synthesized according to Example 8 described in JP2011-37836A.

Synthesis Example 2 [Synthesis of Resin H2]
The monomer (a1-1-3), monomer (a1-2-7), monomer (a2-1-1), monomer (a3-2-3) and monomer (a3-1-1) are mixed in a molar ratio [ Monomer (a1-1-3): monomer (a1-2-7): monomer (a2-1-1): monomer (a3-2-3): monomer (a3-1-1)] is 28:15 : 5: 20: 32 The mixture was further mixed with propylene glycol monomethyl ether acetate 1.5 times by mass with respect to the total mass of all monomers. Into the resulting mixture, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were 1.2 mol% and 3.6 mol%, respectively, with respect to the total number of moles of all monomers. It added so that it might become. This was polymerized by heating at 75 ° C. for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of a mixed solvent of methanol and water (mass ratio methanol: water = 4: 1) to precipitate the resin. This resin was filtered and collected. Once again dissolved in propylene glycol monomethyl ether acetate, poured into a mixed solvent of a large amount of methanol and water to precipitate the resin, and then filtered and recovered the precipitated resin twice to perform reprecipitation and purification. A copolymer having an average molecular weight of 5.5 × 10 ³ was obtained with a yield of 59%. This copolymer has the following structural units each derived from the above-mentioned monomers, and this is designated as resin H2.

Examples 10 to 21, Comparative Examples 1 and 2
(Preparation of resist composition)
Each of the following components was mixed in parts by mass shown in Table 1 and dissolved in a solvent, and then filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

<Resin (A)>
A1: Resin A1
A2: Resin A2
A3: Resin A3
A4: Resin A4
A5: Resin A5
A6: Resin A6
H1: Resin H1
H2: Resin H2

Ｂ１−Ｘ：下記式で表される塩；特開２０１１−２４６４３９号公報記載の方法で合成

<Acid generator (B)>
B1-21: a salt represented by the formula (B1-21); synthesized by the method described in JP2011-126869A

B1-X: salt represented by the following formula; synthesized by the method described in JP2011-246439A

Ｃ２：式（Ｃ９−２）で表される塩；特開２０１２−７２１０９号公報記載の方法で合成

Ｃ３：テトラ−ｎ−ブチルアンモニウムサリチラート（東京化成工業（株）製）
＜溶剤＞
プロピレングリコールモノメチルエーテルアセテート ４００部
プロピレングリコールモノメチルエーテル １５０部
γ−ブチロラクトン ５部 <Quencher (C)>
C1: salt represented by the formula (C9-1); synthesized by the method described in JP2011-39502A

C2: salt represented by formula (C9-2); synthesized by the method described in JP2012-72109A

C3: Tetra-n-butylammonium salicylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
<Solvent>
Propylene glycol monomethyl ether acetate 400 parts Propylene glycol monomethyl ether 150 parts γ-butyrolactone 5 parts

(Manufacture of resist patterns; evaluation of electron beam exposure)
A 6-inch silicon wafer was treated on a direct hot plate with hexamethyldisilazane at 90 ° C. for 60 seconds. This silicon wafer was spin-coated with a resist composition so that the film thickness of the composition layer was 0.04 μm. Thereafter, the composition layer was formed by pre-baking on a direct hot plate for 60 seconds at the temperature shown in the “PB” column of Table 1. Using an electron beam drawing machine ("HL-800D 50keV" manufactured by Hitachi, Ltd.), the line and space pattern is directly drawn on the composition layer formed on the silicon wafer by changing the exposure stepwise. did.
After exposure, post exposure baking is performed for 60 seconds on the hot plate at the temperature shown in the “PEB” column of Table 1, and then paddle development is performed for 60 seconds with an aqueous 2.38 mass% tetramethylammonium hydroxide solution. A resist pattern was obtained.

Fall margin evaluation: For the obtained resist pattern, the fall margin was determined according to the following formula. A larger value indicates that tilting is less likely to occur over a wide exposure range. The results are shown in Table 2.
Fall margin (%) = (E ₂ −E ₁ ) / E ₁ × 100
[E ₁ represents a minimum exposure amount at which a 60 nm line and space pattern is separated.
E ₂ represents the minimum exposure amount at which pattern collapse is observed in a 60 nm line and space pattern formed at a higher exposure amount than E ₁ . ]

(Manufacture of resist pattern; EUV exposure evaluation)
A 4-inch silicon wafer was treated with hexamethyldisilazane at 90 ° C. for 60 seconds on a direct hot plate. This silicon wafer was spin-coated with a resist composition so that the film thickness of the composition layer was 0.035 μm.
Thereafter, the composition layer was formed by pre-baking on a direct hot plate for 60 seconds at the temperature shown in the “PB” column of Table 1. The wafer on which the composition layer was formed was exposed to a line-and-space pattern using an EUV exposure machine while changing the exposure amount stepwise.
After exposure, post exposure baking is performed for 60 seconds on the hot plate at the temperature shown in the “PEB” column of Table 1, and then paddle development is performed for 60 seconds with an aqueous 2.38 mass% tetramethylammonium hydroxide solution. A resist pattern was obtained.

  The obtained resist pattern was subjected to collapse margin evaluation by the same method as described above except that the pattern was observed with a 20 nm line and space pattern. The results are shown in Table 2.

  According to the resin of the present invention, if a resist composition containing the resin is used, a resist pattern can be produced with a wide collapse margin.

Claims (8)

A salt represented by the formula (I).

[In the formula (I),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
X ² represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom, and the divalent saturated hydrocarbon group —CH ₂ — contained in the hydrocarbon group may be replaced by —O— or —CO—.
R ³ represents formula (IA)

(In formula (IA), s1 represents 1 or 2. t1 represents 0 or 1, provided that s1 + t1 is 1 or 2.
R ⁴ represents a saturated hydrocarbon group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group and the aromatic hydrocarbon group is a nitro group. The —CH ₂ — contained in the saturated hydrocarbon group may be replaced with —O—.
u1 represents an integer of 0 to 4. When u1 is 2 or more, the plurality of R ⁴ are the same or different. ) Or formula (IE)

(In Formula (IE), Ring W ^E represents an alicyclic hydrocarbon ring having 3 to 9 carbon atoms.
s12 represents an integer of 0 to 4.
t12 represents an integer of 0 to 2. However, s12 + t12 is 4 or less.
R ⁵ and R ⁶ are each independently a hydroxy group, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, or 2 to 7 carbon atoms. An acyl group having 2 to 7 carbon atoms, or an acylamino group having 2 to 7 carbon atoms. Two of R ⁵ and R ⁶ may be combined to form a ring.
u2 represents an integer of 0 to 14, and when u2 is 2 or more, the plurality of R ⁵ are the same or different.
u3 represents an integer of 0 to 13, and when u3 is 2 or more, the plurality of R ⁶ are the same or different. )
Represents a group represented by
Y ¹ represents the formula (Iy)

(In formula (Iy), R ′ represents a hydrogen atom, a C 1-6 alkyl group which may have a fluorine atom, a hydroxy group or a cyano group.
X ′ represents a single bond, —O—, * —CO—O—, * —Ar—O—, * —Ar—CO—O—, * —CO—O—Ar—O— or * —CO—O. -Ar-CO-O- is represented.
Ar represents a phenylene group.
* Represents a bond with —C (R ′) ═CH ₂ . )
Represents a group represented by
R ¹ and R ² are each independently an optionally substituted aliphatic hydrocarbon group having 1 to 10 carbon atoms and an optionally substituted alicyclic carbon atom having 4 to 36 carbon atoms. A hydrogen group, an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent, or a heterocyclic group having 3 to 36 carbon atoms which may have a substituent.
X ¹ represents a C1-36 divalent hydrocarbon group which may have a substituent, and —CH ₂ — contained in the hydrocarbon group is —O—, —SO ₂ — or -CO- may be substituted. ^{Two of} R ¹ , R ² and X ¹ may be taken together to form a ring containing a sulfur atom. ] The salt according to claim 1, wherein R ³ in formula (I) is a group represented by formula (IA).   Resin containing the structural unit derived from the salt of Claim 1 or 2.   The resin according to claim 3, further comprising a structural unit having an acid labile group.   A resist composition comprising the salt according to claim 1.   A resist composition comprising the resin according to claim 3.   The resist composition according to claim 6, further comprising the salt according to claim 1. (1) The process of apply | coating the resist composition in any one of Claims 5-7 on a board | substrate,
(2) The process of drying the composition after application | coating and forming a composition layer,
(3) a step of exposing the composition layer;
(4) A method for producing a resist pattern, comprising a step of heating the composition layer after exposure, and (5) a step of developing the composition layer after heating.