JP5750242B2 - Resist composition - Google Patents

Description

  The present invention relates to a resist composition, and more particularly to a resist composition used for fine processing of semiconductors.

A resist composition used for microfabrication of a semiconductor using a lithography technique contains a resin.
For example, Patent Document 1 includes a resin having a structural unit derived from monomer A and monomer D, an acid generator composed of tolyldiphenylsulfonium perfluorobutanesulfonate, and a salt represented by formula (C1). A resist composition is described.

JP 2002-122994 A

  Conventional resist compositions may not always satisfy the resolution and line edge roughness (LER) of the pattern obtained.

［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^１は、単結合又は置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれるメチレン基は酸素原子又はカルボニル基で置換されていてもよい。
Ｙ^１は、直鎖状又は分岐状の炭素数１〜３６の脂肪族炭化水素基、炭素数３〜３６の脂環式炭化水素基あるいは炭素数６〜３６の芳香族炭化水素基であり、該脂肪族炭化水素基、脂環式炭化水素基及び芳香族炭化水素基は置換基を有していてもよく、該脂肪族炭化水素基及び脂環式炭化水素基に含まれるメチレン基は酸素原子又はカルボニル基で置換されていてもよい。
Ｚ^＋は、有機カチオンを表す。］

［式（ＩＩ）中、
Ｒ^Ａ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の複素環基を表す。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、酸素原子またはカルボニル基で置換されていてもよい。
Ｚ'^＋は、有機カチオンを表す。］ The present application provides the following inventions.
[1] A resist composition containing an acid generator represented by formula (I), a resin, and a compound represented by formula (II).

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

[In the formula (II),
R ^A 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 aromatic hydrocarbon group having 3 to 36 carbon atoms which may be substituted, or a heterocyclic group having 3 to 36 carbon atoms which may have a substituent. The methylene group contained in the aliphatic hydrocarbon group and the alicyclic hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.
Z ′ ⁺ represents an organic cation. ]

［式（Ｙ１）及び式（Ｙ２）中、
環に含まれる水素原子は、ハロゲン原子、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基又は炭素数２〜４のアシル基で置換されていてもよく、環に含まれるメチレン基は、カルボニル基又は酸素原子で置換されていてもよい。
＊は、Ｘ^１との結合手を表す。］
〔４〕Ｚ'^＋が、式（ＩＩＩ）で表されるカチオンである〔１〕〜〔３〕のいずれか記載のレジスト組成物。

［式（ＩＩＩ）中、
Ｒ^Ｂ、Ｒ^Ｃ及びＲ^Ｄ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の複素環基を表す。該脂肪族炭化水素基、脂環式炭化水素基、芳香族炭化水素基、複素環基に含まれる炭素原子は、硫黄原子、酸素原子又はカルボニル基で置換されていてもよい。Ｒ^Ｂ、Ｒ^Ｃ及びＲ^Ｄのうちの２つが互いに結合して環を形成してもよい。］ [2] The resist composition according to [1], wherein X ¹ is —CO—O— [CH ₂ ] _h — (h represents an integer of 0 to 10).
[3] The resist composition according to [1] or [2], wherein Y ¹ is a group represented by formula (Y1) or formula (Y2).

[In Formula (Y1) and Formula (Y2),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or glycidyl. It may be substituted with an oxy group or an acyl group having 2 to 4 carbon atoms, and the methylene group contained in the ring may be substituted with a carbonyl group or an oxygen atom.
* Represents a bond to ^{X 1.} ]
[4] The resist composition according to any one of [1] to [3], wherein Z ′ ⁺ is a cation represented by the formula (III).

[In the formula (III),
R ^B , R ^C and R ^D are each independently an aliphatic hydrocarbon group having 1 to 10 carbon atoms which may have a substituent, or an aliphatic hydrocarbon group having 4 to 36 carbon atoms which may have a substituent. It represents a cyclic hydrocarbon group, 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 carbon atom contained in the aliphatic hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group or heterocyclic group may be substituted with a sulfur atom, oxygen atom or carbonyl group. Two of R ^B , R ^C and R ^D may be bonded to each other to form a ring. ]

［式（ＩＶ）中、
環に含まれる水素原子は、ハロゲン原子、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基又は炭素数２〜４のアシル基で置換されていてもよく、環に含まれるメチレン基は、カルボニル基又は酸素原子で置換されていてもよい。
＊は、酸素原子との結合手を表す。］
〔６〕樹脂が、酸に不安定な基を有し、かつアルカリ水溶液に不溶又は難溶であり、酸と作用してアルカリ水溶液で溶解しえる樹脂である〔１〕〜〔５〕のいずれか記載のレジスト組成物。
〔７〕上記〔６〕記載の組成物と塩基性化合物とを含有するレジスト組成物。
〔８〕塩基性化合物が、ジイソプロピルアニリンである〔７〕記載のレジスト組成物。 [5] The resist composition according to any one of [1] to [4], wherein R ^A is an alkyl group having 1 to 8 carbon atoms or a group represented by formula (IV).

[In the formula (IV),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or glycidyl. It may be substituted with an oxy group or an acyl group having 2 to 4 carbon atoms, and the methylene group contained in the ring may be substituted with a carbonyl group or an oxygen atom.
* Represents a bond with an oxygen atom. ]
[6] Any one of [1] to [5], wherein the resin has an acid labile group and is insoluble or hardly soluble in an aqueous alkali solution and can be dissolved in an aqueous alkali solution by acting with an acid. A resist composition as described above.
[7] A resist composition comprising the composition according to [6] above and a basic compound.
[8] The resist composition according to [7], wherein the basic compound is diisopropylaniline.

[9] (1) A step of applying the resist composition according to any one of [1] to [7] on a substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) A pattern forming method comprising a step of developing the heated composition layer using a developing device.

  According to the resist composition of the present invention, the resolution and LER of the resulting pattern can be further improved.

［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^１は、単結合又は置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれるメチレン基は酸素原子又はカルボニル基で置換されていてもよい。
Ｙ^１は、直鎖状又は分岐状の炭素数１〜３６の脂肪族炭化水素基、炭素数３〜３６の脂環式炭化水素基あるいは炭素数６〜３６の芳香族炭化水素基であり、該脂肪族炭化水素基、脂環式炭化水素基及び芳香族炭化水素基は置換基を有していてもよく、該脂肪族炭化水素基及び脂環式炭化水素基に含まれるメチレン基は酸素原子又はカルボニル基で置換されていてもよい。
Ｚ^＋は、有機カチオンを表す。］ The resist composition of the present invention contains an acid generator represented by formula (I) (hereinafter sometimes referred to as “acid generator (A)”).

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

In this specification, unless otherwise specified, specific chemical substituents described later can be applied to any chemical structural formula having the same substituents while appropriately selecting the number of carbon atoms. Those which can take any of linear, branched or cyclic are included unless otherwise specified, and in the same group, linear, branched and / or cyclic partial structures are mixed. It may be. When stereoisomers exist, all of those stereoisomers are included.
Further, "(meth) acryl" means at least one having the structure of "CH ₂ = CH-CO-" or _{"CH 2 = C (CH 3)} -CO- ". Similarly, “(meth) acrylate” and “(meth) acrylic acid” mean “at least one of acrylate and methacrylate” and “at least one of acrylic acid and methacrylic acid”, respectively.

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

Examples of the saturated hydrocarbon group include a group containing an alkylene group or a cycloalkylene group.
Examples of the alkylene group include a methylene group, a dimethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, a heptamethylene group, an octamethylene group, a nonamethylene group, a decamethylene group, an undecamethylene group, and a dodecamethylene group. , Tridecamethylene group, tetradecamethylene group, pentadecamethylene group, hexadecamethylene group, heptacamethylene group, ethylene group, propylene group, isopropylene group, sec-butylene group and tert-butylene group.

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

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

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, n-pentyl group, n-hexyl group, heptyl. And linear or branched alkyl groups such as 2-ethylhexyl group, octyl group, nonyl group, decyl group, undecyl group and dodecyl group.
Examples of the alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, a norbornyl group, a 1-adamantyl group, and a 2-adamantyl group. And cycloalkyl groups such as isobornyl group.

  Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthranyl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group; a tolyl group, a xylyl group, a cumenyl group, and a mesityl group. , Aryl groups such as biphenyl group, anthryl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl, and the like. Of these, phenyl, naphthyl, anthranyl, p-methylphenyl, p-tert-butylphenyl, p-adamantylphenyl and the like are suitable.

In the anion of the salt represented by the formula (I) (hereinafter sometimes referred to as the salt (I)) that is an active ingredient of the acid generator (A), Q ¹ and Q ² are each independently a fluorine atom or it is preferably -CF _3, both a fluorine atom is more preferable.

  The methylene group contained in the saturated hydrocarbon group having 1 to 17 carbon atoms may be substituted with an oxygen atom or a carbonyl group.

Examples of the substituent for X ¹ include a halogen atom, a hydroxyl group, a carboxyl group, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, and a carbon number. Examples thereof include an aromatic hydrocarbon group having 6 to 20 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, a glycidyloxy group, and an acyl group having 2 to 4 carbon atoms.

Examples of the halogen atom include fluorine, chlorine, bromine and iodine atoms.
Examples of the aralkyl group include benzyl, phenethyl, phenylpropyl, trityl, naphthylmethyl group, naphthylethyl group, and the like.
Examples of the acyl group include acetyl, propionyl, butyryl and the like.

［式（Ｘ^１−１）中、
Ｘ^a１は、単結合又は置換基を有していてもよい炭素数１〜１５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で置換されていてもよい。
＊は、−Ｃ（Ｑ^１）（Ｑ^２）−との結合手を表す。］
Ｘ^a１における置換基は、Ｘ^１における置換基と同様のものが挙げられる。 X ¹ is preferably a group represented by the formula (X ¹ -1).

[In the formula (X ¹ -1),
X ^a1 represents a single bond or a saturated hydrocarbon group having 1 to 15 carbon atoms which may have a substituent, and the methylene group contained in the saturated hydrocarbon group is substituted with an oxygen atom or a carbonyl group. Also good.
* Represents a bond with —C (Q ¹ ) (Q ² ) —. ]
^Examples of the substituent in X ^a1 include the same substituents as in X ¹ .

Specific examples of X ¹ include the following groups.

X ¹ is suitably —CO—O—X ¹⁰ —, —CO—O—X ¹¹ —CO—O—, —X ¹¹ —O—CO—, —X ¹¹ —O—X ¹² —. And —CO—O—X ¹⁰ — and —CO—O—X ¹¹ —CO—O— are preferable. However, X < ¹⁰ >, X < ¹¹ > and X < ¹² > represent a single bond or a linear or branched C1-C15 alkylene group mutually independently. Furthermore, —CO—O— [CH ₂ ] _h — (h represents an integer of 0 to 10) is more preferable.

Examples of the substituent in Y ¹ include a halogen atom, a hydroxyl group, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, and 7 to 7 carbon atoms. One or more selected from the group consisting of 21 aralkyl groups, C1-C12 alkoxy groups, glycidyloxy groups, and C2-C4 acyl groups.

As an alkoxy group, a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentoxy group, an n-hexoxy group, a heptoxy group, an octoxy group , 2-ethylhexoxy group, nonyloxy group, decyloxy group, undecyloxy group, dodecyloxy group and the like.
Y ¹ is suitably an alicyclic hydrocarbon group having 4 to 36 carbon atoms which may have a substituent.

  Examples of the anion of the salt represented by the formula (I) include the following formula (IA), formula (IB), formula (IC), formula (ID) and the like. Among these, anions represented by formula (IA) and formula (IB) are suitable.

［式（ＩＡ）、式（ＩＢ）、式（ＩＣ）及び式（ＩＤ）中、
Ｑ^１、Ｑ^２及びＹ^１は、式（Ｉ）における定義と同じである。
Ｘ¹⁰、Ｘ¹¹及びＸ¹²は、互いに独立に、単結合あるいは直鎖状又は分岐状の炭素数１〜１５のアルキレン基を表す。］

[In formula (IA), formula (IB), formula (IC) and formula (ID),
Q ¹ , Q ² and Y ¹ are the same as defined in formula (I).
X ¹⁰ , X ¹¹ and X ¹² each independently represent a single bond or a linear or branched alkylene group having 1 to 15 carbon atoms. ]

［式（Ｙ１）中、
環Ｗ’は、炭素数３〜３６の脂環式炭化水素基を表し、該脂環式炭化水素基に含まれるメチレン基は、酸素原子又はカルボニル基で置換されていてもよい。
Ｒ^ｂは、互いに独立に、ハロゲン原子、水酸基、直鎖状又は分岐状の炭素数１〜１２の脂肪族炭化水素基、炭素数６〜２０の芳香族炭化水素基、炭素数７〜２１のアラルキル基、炭素数１〜１２のアルコキシ基、グリシジルオキシ基あるいは炭素数２〜４のアシル基を表す。
ｘは、０〜８の整数を表す。ｘが２以上の場合、複数のＲ^ｂは、同一でも異なってもよい。
Ｒ^ａは、水素原子あるいは直鎖状又は分岐状の炭素数１〜６の炭化水素基を表すか、環Ｗ’に含まれる炭素原子と互いに結合して環を形成していてもよい。］ Y ¹ is preferably a group represented by the formula (Y0).

[In the formula (Y1),
Ring W ′ represents an alicyclic hydrocarbon group having 3 to 36 carbon atoms, and the methylene group contained in the alicyclic hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.
R ^b is independently of each other a halogen atom, a hydroxyl group, a linear or branched aliphatic hydrocarbon group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, or 7 to 21 carbon atoms. An aralkyl group, an alkoxy group having 1 to 12 carbon atoms, a glycidyloxy group, or an acyl group having 2 to 4 carbon atoms is represented.
x represents an integer of 0 to 8. When x is 2 or more, the plurality of R ^b may be the same or different.
R ^a represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms, or may be bonded to a carbon atom contained in the ring W ′ to form a ring. ]

The hydrocarbon includes a saturated or unsaturated hydrocarbon group, and as described above, an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, an aryl, an aralkyl group, or a combination thereof. Can be mentioned.
Examples of the ring include an aromatic or non-aromatic hydrocarbon ring or a heterocyclic ring. These may be further combined to form a polycyclic fused ring.
x preferably represents an integer of 0 to 6, more preferably an integer of 0 to 4.
Examples of the ring W ′ include formula (W1) to formula (W25). Of these, groups represented by formula (W12) and formula (W13) are preferred.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

  Examples of the anion represented by the formula (ID) include the following.

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

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

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

Examples of Z ^{+ in the} salt represented by the formula (I) include cations such as the formula (IXz), the formula (IXb), the formula (IXc), and the formula (IXd).

［式（ＩＸｚ）中、
Ｐ^ａ、Ｐ^ｂ及びＰ^ｃは、互いに独立に、直鎖状又は分岐状の炭素数１〜３０のアルキル基、炭素数３〜３０の脂環式炭化水素基あるいは炭素数６〜２０の芳香族炭化水素基を表す。
Ｐ^ａ、Ｐ^ｂ及びＰ^ｃのいずれかがアルキル基である場合、該アルキル基は、水酸基、直鎖状又は分岐状の炭素数１〜１２のアルコキシ基あるいは炭素数３〜１２の環式炭化水素基で置換されていてもよく、
Ｐ^ａ、Ｐ^ｂ及びＰ^ｃのいずれかが脂環式炭化水素基又は芳香族炭化水素である場合には、水素原子、水酸基、ハロゲン原子、直鎖状又は分岐状の炭素数１〜１２のアルキル基、直鎖状又は分岐状の炭素数１〜１２のアルコキシ基あるいは炭素数４〜３６の脂環式炭化水素を表し、該脂環式炭化水素基に含まれる水素原子は、ハロゲン原子、水酸基、直鎖状又は分岐状の炭素数１〜１２のアルキル基、直鎖状又は分岐状の炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基あるいは炭素数２〜４のアシル基で置換されていてもよい。
式（ＩＸｂ）中、Ｐ^４及びＰ^５は、互いに独立に、水素原子、水酸基、直鎖状又は分岐状の炭素数１〜１２のアルキル基あるいは炭素数１〜１２のアルコキシ基を表す。

[In the formula (IXz),
P ^a , P ^b and P ^c are each independently a linear or branched alkyl group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 30 carbon atoms or an aromatic group having 6 to 20 carbon atoms. Represents a group hydrocarbon group.
When any one of P ^a , P ^b and P ^c is an alkyl group, the alkyl group is a hydroxyl group, a linear or branched alkoxy group having 1 to 12 carbon atoms, or a cyclic carbonization having 3 to 12 carbon atoms. May be substituted with a hydrogen group,
When any of P ^a , P ^b and P ^c is an alicyclic hydrocarbon group or an aromatic hydrocarbon, a hydrogen atom, a hydroxyl group, a halogen atom, a linear or branched ^C 1-12 carbon atom Represents an alkyl group, a linear or branched alkoxy group having 1 to 12 carbon atoms or an alicyclic hydrocarbon having 4 to 36 carbon atoms, and the hydrogen atom contained in the alicyclic hydrocarbon group is a halogen atom, Hydroxyl group, linear or branched alkyl group having 1 to 12 carbon atoms, linear or branched alkoxy group having 1 to 12 carbon atoms, aryl group having 6 to 12 carbon atoms, aralkyl having 7 to 12 carbon atoms Group, a glycidyloxy group, or an acyl group having 2 to 4 carbon atoms.
In formula (IXb), P ⁴ and P ⁵ each independently represent a hydrogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.

In formula (IXc),
P ⁶ and P ⁷ each independently represent a linear or branched alkyl group having 1 to 12 carbon atoms or a cycloalkyl group having 3 to 12 carbon atoms, or P ⁶ and P ⁷ are combined together. A ring having 3 to 12 carbon atoms may be formed.
P ⁸ represents a hydrogen atom, and P ⁹ is a linear or branched alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, or an optionally substituted carbon atom having 6 to 20 carbon atoms. Or P ⁸ and P ⁹ may be combined to form a ring having 3 to 12 carbon atoms.

In formula (IXd),
P ¹⁰ to P ²¹ are independently of each other, represent a hydrogen atom, a hydroxyl group, an alkyl group or an alkoxy group having 1 to 12 carbon atoms having 1 to 12 carbon atoms.
E represents a sulfur atom or an oxygen atom.
m represents 0 or 1. ]

ここで、＊は硫黄原子との結合手を示す。 The alkyl group, alicyclic hydrocarbon group, alkoxy group, cycloalkyl group, ring, aromatic hydrocarbon group and the like are the same as described above.
The cyclic hydrocarbon group may be either saturated or unsaturated, and examples thereof include an alicyclic hydrocarbon group and an aromatic hydrocarbon group.
Examples of the ring formed by combining P ⁶ and P ⁷ include a heterocyclic ring containing at least one sulfur atom. For example, thiirane, thiane, thiin, thiazoline, iazolidine, oxathiolane, tetrahydrothiophenium group and the like are exemplified. Of these, a tetrahydrothiophenium group is preferable.
The substituent of the aromatic hydrocarbon group for P ^9, include alkyl groups of 1 to 12 carbon atoms.
Examples of the ring formed by combining P ⁸ and P ⁹ include the following groups.

Here, * indicates a bond with a sulfur atom.

Among the cations represented by the formula (IXz), for example, a cation represented by the formula (IXa) is preferable.

[In Formula (IXa), P ^{1 to} P ³ are each independently a hydrogen atom, a hydroxyl group, a halogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched carbon atom. Represents an alkoxy group having 1 to 12 carbon atoms or an alicyclic hydrocarbon having 4 to 36 carbon atoms, and the hydrogen atom contained in the alicyclic hydrocarbon group is a halogen atom, a hydroxyl group, a linear or branched carbon number; 1 to 12 alkyl groups, linear or branched alkoxy groups having 1 to 12 carbon atoms, aryl groups having 6 to 12 carbon atoms, aralkyl groups having 7 to 12 carbon atoms, glycidyloxy groups, or 2 to 4 carbon atoms The acyl group may be substituted. ]

  In particular, those containing an adamantyl skeleton and an isobornyl skeleton are suitable as the alicyclic hydrocarbon group, preferably a 2-alkyl-2-adamantyl group, a 1- (1-adamantyl) -1-alkyl group, an isobornyl group, and the like. Is mentioned.

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

  Among the cations represented by the formula (IXa), the cation represented by the formula (IXe) is preferably used because of its easy production.

［式（ＩＸｅ）中、Ｐ^２２、Ｐ^２３及びＰ^２４は、互いに独立に、水素原子、水酸基、ハロゲン原子、直鎖状又は分岐状の炭素数１〜１２のアルキル基あるいは直鎖状又は分岐状の炭素数１〜１２のアルコキシ基を表す。］

[In Formula (IXe), P ²² , P ^23, and P ²⁴ are each independently a hydrogen atom, a hydroxyl group, a halogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched group. Represents an alkoxy group having 1 to 12 carbon atoms. ]

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

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

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

The anions and cations described above can be arbitrarily combined.
For example, the salt represented by the formula (I) includes compounds represented by the formula (Xa) to the formula (Xi).

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

Examples of the ring and P ²⁸ and ^{P 29} are formed together, tetrahydrothiophenium group, thian-1-ium ring, such as 1,4-oxathian-4-ium ring. Among these, a tetrahydrothiophenium group is preferable.
Examples of the ring formed by combining P ³⁰ and P ³¹ include the groups of the above formulas (W13) to (W15), oxocycloheptane ring, oxocyclohexane ring, oxonorbornane ring, oxoadamantane ring, and the like. It is done.

Of the above combinations, the following salts are preferred.

  In the resist composition of this invention, it is preferable that content of an acid generator is 1-20 mass parts with respect to 100 mass parts of resin mentioned later, and it is more preferable that it is 1-15 mass parts.

  The resist composition of the present invention contains a resin (hereinafter sometimes referred to as “resin (B)”). The resin (B) is a resin having an acid labile group and insoluble or hardly soluble in an alkaline aqueous solution, and the resin that has reacted with an acid is a resin that can be dissolved in an alkaline aqueous solution.

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

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

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

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

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

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

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

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

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

The resin used in the present invention may contain a structural unit derived from an acid-stable monomer in addition to a structural unit derived from a monomer having an acid-labile group. Here, the structure derived from an acid-stable monomer means a structure that is not cleaved by the acid generator (A) of the present invention.
Specifically, a structural unit derived from a monomer having a free carboxylic acid group such as acrylic acid or methacrylic acid, or a structural unit derived from an aliphatic unsaturated dicarboxylic anhydride such as maleic anhydride or itaconic anhydride , A structural unit derived from 2-norbornene, a structural unit derived from (meth) acrylonitrile, a carbon atom adjacent to the oxygen atom is a secondary carbon atom or an alkyl ester or 1-adamantyl ester of a tertiary carbon atom (meth) Structural units derived from acrylates, structural units derived from styrene monomers such as p- or m-hydroxystyrene, derived from (meth) acryloyloxy-γ-butyrolactone in which the lactone ring may be substituted with an alkyl group And a structural unit. In the 1-adamantyl ester, the carbon atom adjacent to the oxygen atom is a quaternary carbon atom.

  Specific examples of acid-stable monomers include 3-hydroxy-1-adamantyl (meth) acrylate, 3,5-dihydroxy-1-adamantyl (meth) acrylate, α- (meth) acryloyloxy-γ-butyrolactone, β- (meth) acryloyloxy-γ-butyrolactone, a monomer deriving the structural unit represented by the formula (a), a monomer deriving the structural unit represented by the formula (b), hydroxystyrene, norbornene, etc. Examples thereof include an alicyclic compound having a bond, an aliphatic unsaturated dicarboxylic acid anhydride such as maleic anhydride, and itaconic anhydride.

  Among these, in particular, structural units derived from styrene monomers such as p- or m-hydroxystyrene, structural units derived from 3-hydroxy-1-adamantyl (meth) acrylate, (meth) acrylic acid 3,5 A resist obtained from a resin containing any one of a structural unit derived from -dihydroxy-1-adamantyl, a structural unit represented by formula (a), and a structural unit represented by formula (b) has the following characteristics: This is preferable because the resolution of the image tends to be improved.

（式中、Ｒ¹及びＲ²は、互いに独立に、水素原子又はメチル基を表し、Ｒ³及びＲ⁴は、互いに独立に水素原子、メチル基、トリフルオロメチル基又はハロゲン原子を表し、ｉ及びｊは、１〜３の整数を表す。ｉが２または３のときには、Ｒ³は互いに異なる基であってもよく、ｊが２または３のときには、Ｒ⁴は互いに異なる基であってもよい。）

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or a methyl group; R ³ and R ⁴ each independently represent a hydrogen atom, a methyl group, a trifluoromethyl group, or a halogen atom; And j represents an integer of 1 to 3. When i is 2 or 3, R ³ may be a different group, and when j is 2 or 3, R ⁴ may be a different group. Good.)

  Monomers such as (meth) acrylic acid 3-hydroxy-1-adamantyl and (meth) acrylic acid 3,5-dihydroxy-1-adamantyl are commercially available. For example, the corresponding hydroxyadamantane is converted to (meth) acrylic acid or It can also be produced by reacting with the halide.

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

  Specific examples of the monomer that gives the structural unit represented by formula (a) or formula (b) include (meth) acrylic acid esters of alicyclic lactones having a hydroxyl group such as the following, and mixtures thereof. It is done. These esters can be produced, for example, by a reaction between a corresponding alicyclic lactone having a hydroxyl group and (meth) acrylic acid (see, for example, JP-A No. 2000-26446).

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

In the case of KrF excimer laser exposure and EUV exposure, sufficient transmittance can be obtained even when a structural unit derived from a styrene monomer such as p- or m-hydroxystyrene is used as the structural unit of the resin. Such a copolymer resin can be obtained by radically polymerizing the corresponding (meth) acrylic acid ester monomer, acetoxystyrene, and styrene and then deacetylating with an acid.
Examples of the monomer that derives the structural unit derived from the styrene monomer include the following compounds.

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

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

Here, R ⁵ and R ⁶ in formula (c) are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, a carboxyl group, a cyano group, or —COOU (U is an alcohol residue). Or R ⁵ and R ⁶ are bonded to each other to represent a carboxylic anhydride residue represented by —C (═O) OC (═O) —.
When R ⁵ and R ⁶ are a group —COOU, the carboxyl group is an ester group, and the alcohol residue corresponding to U has, for example, about 1 to 8 carbon atoms that may be substituted. And an alkyl group, a 2-oxooxolan-3- or -4-yl group. Here, in the alkyl group, a hydroxyl group, an alicyclic hydrocarbon residue, or the like may be bonded as a substituent.
Specific examples when R ⁵ and R ⁶ are alkyl groups include a methyl group, an ethyl group, and a propyl group. Specific examples of the alkyl group to which a hydroxyl group is bonded include a hydroxymethyl group and 2-hydroxyethyl group. Group and the like.

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

In addition, if U of R ⁵ and R ⁶ —COOU in the formula (c) is an acid labile group such as an alicyclic ester in which the carbon atom adjacent to the oxygen atom is a quaternary carbon atom, Although it has a norbornene structure, it is a structural unit having an acid labile group. Examples of the monomer containing a norbornene structure and an acid labile group include, for example, 5-norbornene-2-carboxylic acid-t-butyl, 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, and 5-norbornene. 2-carboxylate 1-methylcyclohexyl, 5-norbornene-2-carboxylic acid 2-methyl-2-adamantyl, 5-norbornene-2-carboxylic acid 2-ethyl-2-adamantyl, 5-norbornene-2-carboxylic acid 1- (4-methylcyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1- (4-hydroxycyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1-methyl-1- (4-Oxocyclohexyl) ethyl, 5-norbornene-2-carboxylic acid 1- (1-adama) Chill) -1-methylethyl and the like.

Further, the acid-stable group may contain a structural unit represented by the formula (b1) and a structural unit containing a fluorine atom.

[In the formula (b1),
R ^{b ′} represents a hydrogen atom, a methyl group or a trifluoromethyl group.
AR represents a linear, branched or cyclic hydrocarbon group having 1 to 30 carbon atoms, and at least one hydrogen atom contained in the hydrocarbon group is substituted with a fluorine atom. The methylene group contained in the hydrocarbon group may be substituted with an oxygen atom, a sulfur atom or —N (R ^c ) —, and the hydrogen atom contained in the hydrocarbon group may be a hydroxyl group, a straight chain or a branched chain It may be substituted with an aliphatic hydrocarbon group having 1 to 6 carbon atoms.
R ^c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. ]

Specific examples of the monomer for deriving the structural unit represented by the formula (b1) include the following monomers.

  In the resist composition of the present invention, the resin (B) varies depending on the type of radiation for patterning exposure and the type of acid-labile group, but usually a monomer having an acid-labile group in the resin. The content of the structural unit derived from is adjusted to a range of 10 to 80 mol%.

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

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

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

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

［式（ＩＩ）中、
Ｒ^Ａ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の複素環基を表す。
Ｚ’^＋は、有機カチオンを表す。］ The resist composition of the present invention contains a compound represented by the formula (II) (hereinafter sometimes referred to as “compound (II)”).

[In the formula (II),
R ^A 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.
Z ′ ⁺ represents an organic cation. ]

In the anion of the compound represented by the formula (II), examples of the aliphatic hydrocarbon group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group are the same as those described above.
Examples of the heterocyclic group include a pyrrole group, a furyl group, a thienyl group, an indole group, a benzofuryl group, and a carbazolyl group.

Examples of the substituent in ^RA include a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, and glycidyl. Examples thereof include an oxy group or an acyl group having 2 to 4 carbon atoms. Among these, a halogen atom, particularly a fluorine atom is preferable.

［式（ＩＶ）中、
環に含まれる水素原子は、ハロゲン原子、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基又は炭素数２〜４のアシル基で置換されていてもよく、環に含まれるメチレン基は、カルボニル基又は酸素原子で置換されていてもよい。
＊は、酸素原子との結合手を表す。］ R ^A is preferably a C 1-8 alkyl group or a group represented by the formula (IV).

[In the formula (IV),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or glycidyl. It may be substituted with an oxy group or an acyl group having 2 to 4 carbon atoms, and the methylene group contained in the ring may be substituted with a carbonyl group or an oxygen atom.
* Represents a bond with an oxygen atom. ]

The anion containing a fluorine atom as a substituent in R ^A, fluoroacetic acid, difluoro acetic acid, trifluoroacetic acid, pentafluorobenzene acid, Heputafuroro acid, nona fluorosilicone pentanoic acid, perfluoro dodecanoic acid, perfluoro tridecane acid, perfluorotridecanoic carboxylic And anions derived from acid and 2,2-bistrifluoromethylpropionic acid.

Examples of the anion include anions represented by formula (IIA-1) to formula (IIA-18).

［式（ＩＩＩ）中、
Ｒ^Ｂ、Ｒ^Ｃ及びＲ^Ｄ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の複素環基を表す。これら基に含まれる炭素原子は、硫黄原子、酸素原子又はカルボニル基で置換されていてもよい。Ｒ^Ｂ、Ｒ^Ｃ及びＲ^Ｄのうちの２つが互いに結合して環を形成してもよい。］ Examples of the cation of the compound represented by the formula (II) include the same organic cation as Z ⁺ in the acid generator.
For example, a cation represented by the formula (III) is preferable.

[In the formula (III),
R ^B , R ^C and R ^D are each independently an aliphatic hydrocarbon group having 1 to 10 carbon atoms which may have a substituent, or an aliphatic hydrocarbon group having 4 to 36 carbon atoms which may have a substituent. It represents a cyclic hydrocarbon group, 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 carbon atom contained in these groups may be substituted with a sulfur atom, an oxygen atom or a carbonyl group. Two of R ^B , R ^C and R ^D may be bonded to each other to form a ring. ]

Examples of the substituent in R ^B , R ^C and R ^D include a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and a carbon number. A 7-12 aralkyl group, a glycidyloxy group, a C2-C4 acyl group, etc. are mentioned. Among these, a halogen atom, particularly a fluorine atom is preferable.
The ring formed by R ^B , R ^C and R ^D may be any ring containing at least one sulfur atom. Is done.

Specific examples include cations represented by formula (IIB-1) to formula (IIB-96).

  As the compound represented by the formula (II), a carboxylic acid sulfonium salt, a carboxylic acid iodonium salt, and a carboxyimide compound produced by a dehydration condensation reaction between a carboxylic acid and a compound having a hydroxyimide skeleton are preferable. Among these, it is more preferable to use a carboxylic acid sulfonium salt.

Examples of the carboximide compound produced by a dehydration condensation reaction between a carboxylic acid and a compound having a hydroxyimide skeleton include cations represented by formulas (IIB-97) to (IIB-99).

  Examples of the compound represented by the formula (II) include compounds shown in Table 1 below.

  The compound represented by the formula (II) can be synthesized, for example, by reacting sulfonium hydroxide, iodonium hydroxide, ammonium hydroxide and carboxylic acid in a suitable solvent. Sulfonium hydroxide, iodonium hydroxide, and ammonium hydroxide can be obtained by reacting sulfonium iodide, iodonium iodide, and ammonium iodide with silver oxide in an appropriate solvent.

［式中、Ｚ'及びＲ^Ａは、上記と同じ意味を表す。Ｘはハロゲン原子を表す。］ As a manufacturing method of the compound represented by Formula (II), the manufacturing method represented by the following reaction formula is mentioned, for example.

[Wherein, Z ′ and R ^A represent the same meaning as described above. X represents a halogen atom. ]

Examples of Z ′ ⁺ X ⁻ include triphenylsulfonium iodide.
^A compound represented by the formula (II) can be obtained by reacting Z ′ ⁺ X ⁻ and R ^A —CO ₂ —Ag.

  The content of the compound represented by the formula (II) is suitably 0.1 to 20% by weight, preferably 0.5 to 10% by weight, more preferably 1 to 2% by weight based on the total solid content of the resist composition. 7% by weight.

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

In the formula, R ¹¹ , R ¹² and R ¹⁷ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has about 6 to 10 carbon atoms. Of carbon atoms. Furthermore, at least one hydrogen atom on the alkyl group, cycloalkyl group or aryl group may be independently substituted with a hydroxyl group, an amino group or an alkoxy group having 1 to 6 carbon atoms. . At least one hydrogen atom on the amino group may be independently substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹³ and R ¹⁴ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an alkoxy group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has 6 to 10 carbon atoms. The alkoxy group preferably has 1 to 6 carbon atoms. Alternatively, R ¹³ and R ¹⁴ may be bonded to form an aromatic ring.
Furthermore, at least one hydrogen atom on the alkyl group, cycloalkyl group, aryl group or alkoxy group is each independently substituted with a hydroxyl group, an amino group or an alkoxy group having about 1 to 6 carbon atoms. It may be. At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹⁵ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group or a nitro group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has 6 to 10 carbon atoms. The alkoxy group preferably has 1 to 6 carbon atoms.
Furthermore, at least one hydrogen atom on the alkyl group, cycloalkyl group, aryl group or alkoxy group is each independently substituted with a hydroxyl group, an amino group or an alkoxy group having about 1 to 6 carbon atoms. It may be. At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹⁶ represents an alkyl group or a cycloalkyl group. The alkyl group preferably has about 1 to 6 carbon atoms, and the cycloalkyl group preferably has about 5 to 10 carbon atoms. Furthermore, at least one hydrogen atom on the alkyl group or cycloalkyl group may be independently substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹⁸ , R ¹⁹ and R ²⁰ each independently represents an alkyl group, a cycloalkyl group or an aryl group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has 6 to 10 carbon atoms. Has about carbon atoms. Further, at least one hydrogen atom on the alkyl group, cycloalkyl group or aryl group may be independently substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. . At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

W represents an alkylene group, a carbonyl group, an imino group, a sulfide group or a disulfide group. The alkylene group preferably has about 2 to 6 carbon atoms.
Further, in R ^{11 to} R ²⁰ , any of those that can take both a linear structure and a branched structure may be used.
Examples of the aromatic ring include aromatic hydrocarbons (such as aryl or aralkyl) and aromatic heterocycles. Examples of the aromatic heterocycle include a ring in which an arbitrary carbon atom of an aromatic hydrocarbon is replaced with an oxygen atom, a sulfur atom, or a nitrogen atom. Preferably, it is an aromatic hydrocarbon.

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

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

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

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

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

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

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

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

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

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

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.
In Examples and Comparative Examples, “%” and “part” representing content and use amount are based on mass unless otherwise specified. The weight average molecular weight is a value obtained by gel permeation chromatography (HLC-8120GPC type, manufactured by Tosoh Corporation, three columns are “TSKgel Multipore HXL-M”, and the solvent is tetrahydrofuran) using polystyrene as a standard product. .

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

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

Synthesis of Compound C1 Represented by Formula (II) 5.00 parts of triphenylsulfonium iodide and 20.00 parts of methanol were charged and stirred at 23 ° C. for 30 minutes, and 2.00 parts of silver acetate and 100. 00 parts of the suspension was added dropwise over 30 minutes. Furthermore, it stirred at 23 degreeC for 1 hour, and filtered. The obtained filtrate was concentrated, and 100.00 parts of ion-exchanged water was added and stirred, followed by filtration. The obtained filtrate was concentrated and dried to obtain 3.59 parts of compound (C1).

MS (ESI (+) Spectrum): M ⁺ 263.1
MS (ESI (-) Spectrum): M ^- 59.0
¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.49 (s, 3H), 7.70-7.90 (m, 15H)

化合物（Ｃ２−ａ）２１．２５部及びアセトニトリル１００．００部を仕込み、２３℃で３０分間攪拌した。その後、酸化銀１２．４２部を仕込み、２３℃で４時間攪拌し、ろ過した。得られた濾物に、ｔｅｒｔ−ブチルメチルエーテル６３．７５部を添加し、２３℃で３０分間攪拌し、ろ過した。得られた濾物を乾燥することにより、化合物（Ｃ２−ａ）の銀塩３０．６９部を得た。 Synthesis of compound C2 represented by formula (II)

21.25 parts of compound (C2-a) and 100.00 parts of acetonitrile were charged and stirred at 23 ° C. for 30 minutes. Thereafter, 12.42 parts of silver oxide was charged, stirred at 23 ° C. for 4 hours, and filtered. To the obtained filtrate, 63.75 parts of tert-butyl methyl ether was added, stirred at 23 ° C. for 30 minutes, and filtered. The obtained filtrate was dried to obtain 30.69 parts of a silver salt of the compound (C2-a).

  6.48 parts of triphenylsulfonium iodide and 50.00 parts of methanol were added and stirred at 23 ° C. for 30 minutes to suspend 5.00 parts of the silver salt of compound (C2-a) and 150.00 parts of ion-exchanged water. The solution was added dropwise over 1 hour. Furthermore, it stirred at 23 degreeC for 5 hours, and filtered. The obtained filtrate was concentrated, and 30.75 parts of methanol was added and stirred. Thereafter, the mixture was concentrated, and 21.64 parts of ethyl acetate was added to the obtained concentrate. The mixture was stirred at 23 ° C. for 1 hour, and the precipitate was filtered. The obtained filtrate was dried to obtain 3.45 parts of compound (C2) as a white powder.

MS (ESI (+) Spectrum): M ⁺ 263.1
MS (ESI (-) Spectrum): M ^- 193.1
¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 1.70-2.00 (m, 11H), 2.25-2.30 (m, 2H), 7 .70-7.90 (m, 15H)

ジフェニルヨードニウムクロライド５．２６部及びメタノール５０．００部を仕込み、２３℃で３０分間攪拌し、化合物（Ｃ２−ａ）の銀塩５．００部及びイオン交換水１５０．００部の懸濁液を１時間かけて滴下した。さらに、２３℃で３時間攪拌し、ろ過した。得られた濾液を濃縮し、メタノール３０．００部を添加攪拌した。その後、濃縮し、さらに、得られた濃縮物に酢酸エチル２０．００部及びｔｅｒｔ−ブチルメチルエーテル１０．００部を添加した。２３℃で１時間攪拌し、析出物をろ過することにより、化合物（Ｃ３）３．０５部を得た。 Synthesis of compound C3 represented by formula (II)

Charge 5.26 parts of diphenyliodonium chloride and 50.00 parts of methanol and stir at 23 ° C. for 30 minutes to obtain a suspension of 5.00 parts of the silver salt of compound (C2-a) and 150.00 parts of ion-exchanged water. The solution was added dropwise over 1 hour. Furthermore, it stirred at 23 degreeC for 3 hours, and filtered. The obtained filtrate was concentrated, and 30.00 parts of methanol was added and stirred. Thereafter, the mixture was concentrated, and 20.00 parts of ethyl acetate and 10.00 parts of tert-butyl methyl ether were added to the resulting concentrate. The mixture was stirred at 23 ° C. for 1 hour, and the precipitate was filtered to obtain 3.05 parts of compound (C3).

MS (ESI (+) Spectrum): M ⁺ 281.0
MS (ESI (-) Spectrum): M ^- 193.1

（Ｃ４−ａ）で表される塩４．７７部及びメタノール５０．００部を仕込み、２３℃で３０分間攪拌し、化合物（Ｃ２−ａ）の銀塩５．００部及びイオン交換水１５０．００部の懸濁液を１時間かけて滴下した。さらに、２３℃で３時間攪拌し、ろ過した。得られた濾液を濃縮し、メタノール３０．００部を添加攪拌した。その後、濃縮し、得られた濃縮物に、メチル−ｔｅｒｔ−ブチルエーテル３０部を添加し、攪拌した後、２層に分離した上澄み液を除去して下層を取り出し、これを濃縮した。得られた濃縮液に酢酸エチル３０．００部を添加し、攪拌した後、２層に分離した上澄み液を除去し、下層を取り出してこれを濃縮することによって、化合物（Ｃ４）１．４８部を得た。 Synthesis of compound C4 represented by formula (II)

4.77 parts of the salt represented by (C4-a) and 50.00 parts of methanol are charged and stirred at 23 ° C. for 30 minutes, and 5.00 parts of the silver salt of compound (C2-a) and 150. 00 parts of the suspension was added dropwise over 1 hour. Furthermore, it stirred at 23 degreeC for 3 hours, and filtered. The obtained filtrate was concentrated, and 30.00 parts of methanol was added and stirred. Thereafter, the mixture was concentrated, and 30 parts of methyl-tert-butyl ether was added to the resulting concentrate, followed by stirring. After removing the supernatant liquid separated into two layers, the lower layer was taken out and concentrated. After adding 30.00 parts of ethyl acetate to the obtained concentrated liquid and stirring, the supernatant liquid separated into two layers was removed, and the lower layer was taken out and concentrated to obtain 1.48 parts of compound (C4). Got.

MS (ESI (+) Spectrum): M ^<+> 207.1
MS (ESI (-) Spectrum): M ^- 193.1

（Ｃ５−ａ）で表される塩５．６６部及びメタノール５０．００部を仕込み、２３℃で３０分間攪拌し、化合物（Ｃ２−ａ）の銀塩５．００部及びイオン交換水１５０．００部の懸濁液を１時間かけて滴下した。さらに、２３℃で３時間攪拌し、ろ過した。得られた濾液を濃縮し、メタノール４０．００部を添加攪拌した。その後、濃縮し、さらに、得られた濃縮物に酢酸エチル３０．００部を添加した。２３℃で１時間攪拌し、析出物をろ過することにより、化合物（Ｃ５）３．３３部を得た。 Synthesis of Compound C5 Represented by Formula (II)

5.66 parts of the salt represented by (C5-a) and 50.00 parts of methanol are charged and stirred at 23 ° C. for 30 minutes, and 5.00 parts of the silver salt of compound (C2-a) and 150. 00 parts of the suspension was added dropwise over 1 hour. Furthermore, it stirred at 23 degreeC for 3 hours, and filtered. The obtained filtrate was concentrated, and 40.00 parts of methanol was added and stirred. Thereafter, the mixture was concentrated, and 30.00 parts of ethyl acetate was added to the obtained concentrate. The mixture was stirred at 23 ° C. for 1 hour, and the precipitate was filtered to obtain 3.33 parts of the compound (C5).

MS (ESI (+) Spectrum): M ⁺ 305.1
MS (ESI (-) Spectrum): M ^- 193.1

化合物（Ｃ６−ａ）１３．３６部及びアセトニトリル８０．００部を仕込み、２３℃で３０分間攪拌した。その後、酸化銀１２．４２部を仕込み、２３℃で４時間攪拌し、ろ過した。得られた濾物に、ｔｅｒｔ−ブチルメチルエーテル５０．００部を添加し、２３℃で３０分間攪拌し、ろ過した。得られた濾物を乾燥することにより、化合物（Ｃ６−ａ）の銀塩２２．９３部を得た。 Synthesis of compound C6 represented by formula (II)

13.36 parts of compound (C6-a) and 80.00 parts of acetonitrile were charged and stirred at 23 ° C. for 30 minutes. Thereafter, 12.42 parts of silver oxide was charged, stirred at 23 ° C. for 4 hours, and filtered. To the obtained filtrate was added 50.00 parts of tert-butyl methyl ether, and the mixture was stirred at 23 ° C. for 30 minutes and filtered. The obtained filtrate was dried to obtain 22.93 parts of a silver salt of compound (C6-a).

  4.96 parts of triphenylsulfonium chloride and 50.00 parts of methanol are charged, and stirred at 23 ° C. for 30 minutes to obtain a suspension of 3.80 parts of the silver salt of compound (C6-a) and 100.00 parts of ion-exchanged water. Was added dropwise over 30 minutes. Furthermore, it stirred at 23 degreeC for 5 hours, and filtered. The obtained filtrate was concentrated, and 50.00 parts of methanol was added and stirred. Thereafter, the mixture was concentrated, and 30 parts of methyl-tert-butyl ether was added to the resulting concentrate, followed by stirring. After removing the supernatant liquid separated into two layers, the lower layer was taken out and concentrated. After adding 30.00 parts of ethyl acetate to the obtained concentrated liquid and stirring, the supernatant liquid separated into two layers was removed, and the lower layer was taken out and concentrated to obtain 2.29 parts of compound (C6). Got.

MS (ESI (+) Spectrum): M ⁺ 263.1
MS (ESI (-) Spectrum): M ^- 121.0

化合物（Ｃ７−ａ）１５．１１部及びアセトニトリル８０．００部を仕込み、２３℃で３０分間攪拌した。その後、酸化銀１２．４２部を仕込み、２３℃で４時間攪拌し、ろ過した。得られた濾物に、ｔｅｒｔ−ブチルメチルエーテル５０．００部を添加し、２３℃で３０分間攪拌し、ろ過した。得られた濾物を乾燥することにより、化合物（Ｃ７−ａ）の銀塩１６．９８部を得た。 Synthesis of compound C7 represented by formula (II)

15.11 parts of compound (C7-a) and 80.00 parts of acetonitrile were charged and stirred at 23 ° C. for 30 minutes. Thereafter, 12.42 parts of silver oxide was charged, stirred at 23 ° C. for 4 hours, and filtered. To the obtained filtrate was added 50.00 parts of tert-butyl methyl ether, and the mixture was stirred at 23 ° C. for 30 minutes and filtered. The obtained filtrate was dried to obtain 16.98 parts of silver salt of compound (C7-a).

  4.96 parts of triphenylsulfonium chloride and 50.00 parts of methanol were added and stirred at 23 ° C. for 30 minutes to obtain a suspension of 4.06 parts of the silver salt of compound (C7-a) and 100.00 parts of ion-exchanged water. Was added dropwise over 30 minutes. Furthermore, it stirred at 23 degreeC for 5 hours, and filtered. The obtained filtrate was concentrated, and 50.00 parts of methanol was added and stirred. Thereafter, the mixture was concentrated, and 30 parts of methyl-tert-butyl ether was added to the resulting concentrate, followed by stirring. After removing the supernatant liquid separated into two layers, the lower layer was taken out and concentrated. After adding 30.00 parts of ethyl acetate to the obtained concentrated liquid and stirring, the supernatant liquid separated into two layers was removed, and the lower layer was taken out and concentrated to obtain 1.48 parts of compound (C7). Got.

MS (ESI (+) Spectrum): M ⁺ 263.1
MS (ESI (-) Spectrum): M ^- 137.0

[Synthesis of Resin B1]
Monomer E, monomer F, monomer B, monomer C, and monomer D were charged at a molar ratio of 28: 14: 6: 21: 31, and 1.5 weight times dioxane of the total monomer amount was added to obtain a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and heated at 75 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a mixed solvent of a large amount of methanol and water three times to obtain a copolymer having a weight average molecular weight of 8.5 × 10 ^{3 in} a yield of 74%. . This copolymer has each structural unit of the following formula, and this is designated as resin B1.

[Synthesis of Resin B2]
Monomer A, monomer B, and monomer D were charged at a molar ratio of 50:25:25, and 1.5 weight times dioxane of the total monomer amount was added to prepare a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and heated at 77 ° C. for about 5 hours. Thereafter, the reaction solution was purified by pouring it into a mixed solvent of a large amount of methanol and water three times to obtain a copolymer having a weight average molecular weight of 8.1 × 10 ^{3 in} a yield of 55%. . This copolymer has each structural unit of the following formula, and this is designated as resin B2.

[Synthesis of Resin B3]
39.7 g (0.16 mol) of 2-ethyl-2-adamantyl methacrylate and 103.8 g (0.64 mol) of p-acetoxystyrene were dissolved in 265 g of isopropanol and heated to 75 ° C. in a nitrogen atmosphere. . The radical initiator dimethyl 2,2-azobis (2-methylpropionate) 11.05 g (0.048 mol) was dissolved in 22.11 g of isopropanol and added dropwise. The reaction solution was heated to reflux for 12 hours. After cooling, the reaction solution was poured into a large amount of methanol, and the polymer was precipitated and filtered. The obtained copolymer of 2-ethyl-2-adamantyl methacrylate and p-acetoxystyrene was 250 g (containing methanol).

250 g of the obtained copolymer and 10.3 g (0.084 mol) of 4-dimethylaminopyridine were added to 202 g of methanol and heated to reflux for 20 hours. After cooling, the reaction solution was neutralized with 7.6 g (0.126 mol) of glacial acetic acid and poured into a large amount of water to cause precipitation. The precipitated polymer was separated by filtration, dissolved in acetone, poured into a large amount of water and precipitated, and purified by repeating three times. The obtained copolymer of 2-ethyl-2-adamantyl methacrylate and p-hydroxystyrene was 95.9 g. The weight average molecular weight was about 8.6 × 10 ³ (in terms of GPC polystyrene), and the copolymerization ratio was about 20:80 (C13 NMR measurement). This resin is designated as B3.

[Synthesis of Resin B4]
Using 59.6 g (0.24 mol) of 2-ethyl-2-adamantyl methacrylate and 90.8 g (0.56 mol) of p-acetoxystyrene, the same operation as the synthesis of Resin B3 was carried out to obtain methacrylic acid. 102.8 g of a copolymer of 2-ethyl-2-adamantyl and p-hydroxystyrene was obtained. The weight average molecular weight was about 8.2 × 10 ³ (GPC polystyrene conversion), and the copolymerization ratio was about 30:70 (C13 NMR measurement). This resin is designated as B4.

[Synthesis of Resin B5]
Using the radical initiator dimethyl 2,2-azobis (2-methylpropionate) 44.20 g (0.192 mol), the same operation as in the synthesis of the resin B3 was carried out to give 2-ethyl-2-methacrylate 82.4 g of adamantyl and p-hydroxystyrene copolymer was obtained. The weight average molecular weight was about 3.0 × 10 ³ (GPC polystyrene conversion), and the copolymerization ratio was about 20:80 (C13 NMR measurement). This resin is designated as B5.

[Synthesis of Resin B6]
Using the radical initiator dimethyl 2,2-azobis (2-methylpropionate) 44.20 g (0.192 mol), the same operation as in the synthesis of the resin B3 was carried out to give 2-ethyl-2-methacrylate 93.6 g of adamantyl and p-hydroxystyrene copolymer was obtained. The weight average molecular weight was about 3.0 × 10 ³ (in terms of GPC polystyrene), and the copolymerization ratio was about 30:70 (C13 NMR measurement). This resin is designated as B6.

[Synthesis of Resin B7]
75.00 g (0.32 mol) of 2-methyl-2-adamantyl methacrylate and 77.85 g (0.48 mol) of p-acetoxystyrene were dissolved in 285 g of isopropanol and heated to 75 ° C. in a nitrogen atmosphere. . Radical initiator dimethyl 2,2-azobis (2-methylpropionate) 41.44 g (0.180 mol) was dissolved in isopropanol 82.88 g and added dropwise. The reaction solution was heated to reflux for 12 hours. After cooling, the reaction solution was poured into a large amount of methanol, and the polymer was precipitated and filtered. The obtained copolymer of 2-methyl-2-adamantyl methacrylate and p-acetoxystyrene was 275 g (containing methanol).

275 g of the obtained copolymer and 10.3 g (0.084 mol) of 4-dimethylaminopyridine were added to 200 g of methanol and heated to reflux for 20 hours. After cooling, the reaction solution was neutralized with 7.6 g (0.126 mol) of glacial acetic acid and poured into a large amount of water to cause precipitation. The precipitated polymer was separated by filtration, dissolved in acetone, poured into a large amount of water and precipitated, and purified by repeating three times. The obtained copolymer of 2-methyl-2-adamantyl methacrylate and p-hydroxystyrene was 88.6 g. The weight average molecular weight was about 4.0 × 10 ³ (GPC polystyrene conversion), and the copolymerization ratio was about 40:60 (C13 NMR measurement). This resin is designated as B7.

[Synthesis of Resin B8]
Monomer A and monomer D were charged at a molar ratio of 55:45, and 1.5 times the total amount of dioxane was added to form a solution. As initiators, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) were added in an amount of 0.9 mol% and 2.7 mol% based on the total amount of monomers, respectively, and heated at 70 ° C. for about 5 hours. . Thereafter, the reaction solution was purified by pouring it into a large amount of methanol / water mixed solvent and precipitating three times to obtain a copolymer having a weight average molecular weight of 1.1 × 10 ^{4 in} a yield of 68%. . This copolymer has each structural unit of the following formula, and this is designated as resin B8.

Examples and Comparative Examples The components shown in Tables 2 to 4 below were mixed and dissolved, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare resist compositions.

酸発生剤Ａ２

酸発生剤Ｈ１：トリルジフェニルスルホニウム パーフルオロブタンスルホネート
＜樹脂＞
樹脂Ｂ１〜Ｂ８
＜塩基性化合物：クエンチャー＞
クエンチャーＱ１：２，６−ジイソプロピルアニリン
クエンチャーＱ２：テトラブチルアンモニウムヒドロキシド
＜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 ３００．０部
プロピレングリコールモノメチルエーテル ２０．０部
γ−ブチロラクトン ３．５部 <Acid generator>
Acid generator A1

Acid generator A2

Acid generator H1: Tolyldiphenylsulfonium perfluorobutanesulfonate <Resin>
Resins B1 to B8
<Basic compound: Quencher>
Quencher Q1: 2,6-Diisopropylanilink Enture Q2: Tetrabutylammonium hydroxide <solvent>
Propylene glycol monomethyl ether acetate 300.0 parts Propylene glycol monomethyl ether 20.0 parts γ-butyrolactone 3.5 parts

(Evaluation as a photoresist composition)
An organic antireflective coating composition (ARC-29; manufactured by Nissan Chemical Co., Ltd.) is applied to a silicon wafer and baked at 205 ° C. for 60 seconds to form an organic antireflective coating having a thickness of 78 nm. Formed.
Subsequently, the resist compositions of Examples 1 to 9 and Comparative Example 1 were spin-coated on the organic antireflection film so that the film thickness after drying was 85 nm.

After applying the resist composition, the obtained silicon wafer was pre-baked (PB) for 60 seconds on the direct hot plate at the temperature shown in the PB column of Table 2. The ArF excimer stepper [FPA5000-AS3; manufactured by Canon Inc., NA = 0.75, 2 / 3Annular] is used on the silicon wafer on which the resist film is formed in this manner, and the amount of exposure is changed stepwise to line and space. The pattern was exposed.
After exposure, post exposure bake (PEB) is performed for 60 seconds at the temperature shown in the PB column of Table 2 on the hot plate, and then paddle development is performed for 60 seconds with a 2.38 wt% tetramethylammonium hydroxide aqueous solution. It was.

  Resolution evaluation: 100 nm line and space pattern was exposed at an exposure amount of 1: 1, and the resist pattern was observed with a scanning electron microscope. A sample with a resolution of 85 nm was marked with ◯. A sample with no resolution, a resolved image with a rounded top, a trailing edge, or a pattern collapse was marked with ×.

Line edge roughness evaluation (LER): The wall surface of the resist pattern after the lithography process exposed at an exposure amount at which a 100 nm line and space pattern is 1: 1 was observed with a scanning electron microscope. When the contact width of the unevenness on the side wall is 8 nm or less, the circle is marked with ◯, and the width exceeding 8 nm is marked with x.
These results are shown in Table 5.

(Evaluation as a resist composition for electron beams)
The silicon wafer was processed at 90 ° C. for 60 seconds using hexamethyldisilazane on a direct hot plate.
Next, the resist compositions of Examples 10 to 18 and Comparative Example 2 were spin-coated so that the film thickness after drying was 60 nm.
After applying the resist composition, the obtained silicon wafer was pre-baked on a direct hot plate at a temperature shown in the PB column of Table 3 for 60 seconds. Using the electron beam drawing machine ("HL-800D 50 keV" manufactured by Hitachi, Ltd.) on the silicon wafer on which the resist film is formed in this manner, the exposure amount is changed stepwise to form a line and space pattern. Exposed.
After exposure, post-exposure baking was performed for 60 seconds at a temperature shown in the PEB column of Table 3 on a hot plate, and paddle development was further performed for 60 seconds with a 2.38 wt% tetramethylammonium hydroxide aqueous solution.
The pattern after development on the silicon substrate was observed with a scanning electron microscope. The results are shown in Table 6.

  Resolution evaluation: 100 nm line and space pattern was exposed at an exposure amount of 1: 1, and the resist pattern was observed with a scanning electron microscope. The case where 80 nm is resolved is indicated by ◯, and the case where the resolution is not resolved or the resolution is observed but the top is round, the tail is observed, or the pattern collapse is observed is indicated by ×.

  Line edge roughness evaluation (LER): The wall surface of the resist pattern after the lithography process exposed with an exposure amount at which a 100 nm line and space pattern is 1: 1 was observed with a scanning electron microscope. When the contact width of the unevenness on the side wall is 8 nm or less, the circle is marked with ◯, and the width exceeding 8 nm is marked with x.

（ＥＵＶ用レジスト組成物としての評価）
シリコンウェハを、ダイレクトホットプレート上にて、ヘキサメチルジシラザンを用いて９０℃で６０秒処理した。
次いで、実施例１９〜２３のレジスト組成物を、乾燥後の膜厚が５０ｎｍとなるようにスピンコートした。
レジスト組成物塗布後、得られたシリコンウェハをダイレクトホットプレート上にて、表４に示す温度で６０秒間プリベークした。このようにしてレジスト膜が形成されたシリコンウェハに、ＥＵＶ露光機を用い、露光量を段階的に変化させてラインアンドスペースパターンを露光した。
露光後は、ホットプレート上にて、表４に示す温度で６０秒間ポストエキスポジャーベークを行い、さらに２．３８重量％テトラメチルアンモニウムヒドロキシド水溶液で６０秒間のパドル現像を行った。
シリコン基板上のもので現像後のパターンを走査型電子顕微鏡で観察し、その結果を表７に示した。

(Evaluation as a resist composition for EUV)
The silicon wafer was processed at 90 ° C. for 60 seconds using hexamethyldisilazane on a direct hot plate.
Next, the resist compositions of Examples 19 to 23 were spin-coated so that the film thickness after drying was 50 nm.
After applying the resist composition, the obtained silicon wafer was pre-baked on a direct hot plate at a temperature shown in Table 4 for 60 seconds. The silicon wafer on which the resist film was formed in this manner was exposed to a line and space pattern using an EUV exposure machine while changing the exposure amount stepwise.
After exposure, post-exposure baking was performed for 60 seconds at a temperature shown in Table 4 on a hot plate, and paddle development was further performed for 60 seconds with a 2.38 wt% tetramethylammonium hydroxide aqueous solution.
The developed pattern on a silicon substrate was observed with a scanning electron microscope. The results are shown in Table 7.

  Resolution evaluation: The pattern when exposed with an exposure amount at which the 50 nm line and space pattern was 1: 1 was observed with a scanning electron microscope. A sample with a resolution of 45 nm was marked with ◯. A sample with no resolution, a resolved image with a rounded top, a trailing edge, or a pattern collapse was marked with ×.

  Line Edge Roughness Evaluation (LER): The wall surface of the resist pattern after the lithography process exposed with an exposure amount at which a 50 nm line and space pattern is 1: 1 was observed with a scanning electron microscope. When the contact width of the unevenness on the side wall is 7 nm or less, the circle is marked with ◯, and when the width exceeds 7 nm is marked with x.

  Since the resist composition of the present invention exhibits high resolution and good line edge roughness (LER), a chemically amplified photoresist composition suitable for excimer laser lithography such as ArF and KrF, ArF immersion exposure lithography, and EUV exposure lithography. Can be used as In addition to immersion exposure, it can also be used for dry exposure. Furthermore, it can be used for double imaging and is industrially useful.

Claims (9)

A resist composition comprising an acid generator represented by formula (I), a resin, and a compound represented by formula (II).

[In the formula (I),
Q ¹ and Q ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.
X ¹ represents a single bond or a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a substituent, and the methylene group contained in the saturated hydrocarbon group is substituted with an oxygen atom or a carbonyl group. Also good.
Y ¹ is a linear or branched aliphatic hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, The aliphatic hydrocarbon group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a substituent, and the methylene group contained in the aliphatic hydrocarbon group and alicyclic hydrocarbon group is oxygen. It may be substituted with an atom or a carbonyl group. However, a fluorine atom is excluded as the substituent.
Z ⁺ represents an organic cation. ]

[In the formula (II),
R ^A represents an alicyclic hydrocarbon group having 4 to 36 carbon atoms which may have a substituent or a heterocyclic group having 3 to 36 carbon atoms which may have a substituent. The methylene group contained in the alicyclic hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.
Z ′ ⁺ represents an organic cation. However, organic ammonium cations are excluded. ] The resist composition according to claim ¹ , wherein X ¹ is —CO—O— [CH ₂ ] _h — (h represents an integer of 0 to 10). The resist composition according to claim 1, wherein Y ¹ is a group represented by the formula (Y1) or the formula (Y2).

[In Formula (Y1) and Formula (Y2),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or glycidyl. It may be substituted with an oxy group or an acyl group having 2 to 4 carbon atoms, and the methylene group contained in the ring may be substituted with a carbonyl group or an oxygen atom.
* Represents a bond with X ¹ . ] The resist composition according to claim 1, wherein Z ′ ⁺ is a cation represented by the formula (III).

[In the formula (III),
R ^B , R ^C and R ^D are each independently an aliphatic hydrocarbon group having 1 to 10 carbon atoms which may have a substituent, or an aliphatic hydrocarbon group having 4 to 36 carbon atoms which may have a substituent. It represents a cyclic hydrocarbon group, 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 carbon atom contained in the aliphatic hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group or heterocyclic group may be substituted with a sulfur atom, oxygen atom or carbonyl group. Two of R ^B , R ^C and R ^D may be bonded to each other to form a ring. ] The resist composition according to any one of claims 1 to 4, wherein R ^A is an alkyl group having 1 to 8 carbon atoms or a group represented by formula (IV).

[In the formula (IV),
The hydrogen atom contained in the ring is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or glycidyl. It may be substituted with an oxy group or an acyl group having 2 to 4 carbon atoms, and the methylene group contained in the ring may be substituted with a carbonyl group or an oxygen atom.
* Represents a bond with an oxygen atom. ]   The resist composition according to any one of claims 1 to 5, wherein the resin is a resin having an acid labile group and insoluble or hardly soluble in an aqueous alkali solution and capable of dissolving in an aqueous alkali solution by acting with an acid. object.   A resist composition comprising the composition according to claim 6 and a basic compound.   The resist composition according to claim 7, wherein the basic compound is diisopropylaniline. (1) The process of apply | coating the resist composition in any one of Claims 1-8 on a board | substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer using an exposure machine;
(4) A step of heating the composition layer after exposure,
(5) A pattern forming method comprising a step of developing the heated composition layer using a developing device.