JP2011248342A - Resist composition - Google Patents

Abstract

【選択図】なしA resist composition having a wide focus margin when forming a resist pattern is provided.
A resin having an acid labile group and insoluble or hardly soluble in an alkaline aqueous solution and soluble in an alkaline aqueous solution by the action of an acid, an acid generator, and a compound represented by the formula (I): And a compound containing a resist composition. [In Formula (I), R ¹ , R ² and R ³ each independently represents an alkyl group having 1 to 6 carbon atoms. s, t, and u each independently represent an integer of 0 to 3. When s is an integer of 2 or more, the plurality of R ¹ may be the same or different, and when t is an integer of 2 or more, the plurality of R ² may be the same or different. Well, when u is an integer of 2 or more, the plurality of R ³ may be the same or different, and when n is an integer of 2 or more, the plurality of t are the same or different. Also good. n represents an integer of 1 to 3. ]

[Selection figure] None

Description

  The present invention relates to a resist composition.

  Patent Document 1 discloses a resin having an acid labile group and insoluble or hardly soluble in an alkaline aqueous solution, which can be dissolved in an alkaline aqueous solution by the action of an acid, an acid generator, and a basic compound. A resist composition containing 2,6-diisopropylaniline is described.

JP 2006-257078 A

  Conventional resist compositions may not always satisfy a focus margin when forming a resist pattern.

［式（Ｉ）中、Ｒ^１、Ｒ^２及びＲ^３は、それぞれ独立に、炭素数１〜６のアルキル基を表す。
ｓ、ｔ及びｕは、それぞれ独立に、０〜３の整数を表す。ｓが２以上の整数であるとき、複数のＲ^１は同一であっても異なっていてもよく、ｔが２以上の整数であるとき、複数のＲ^２は同一であっても異なっていてもよく、ｕが２以上の整数であるとき、複数のＲ^３は同一であっても異なっていてもよく、ｎが２以上の整数であるとき、複数のｔは同一であっても異なっていてもよい。
ｎは１〜３の整数を表す。］ The present invention includes the following inventions.
[1] A resin having an acid labile group and insoluble or hardly soluble in an alkaline aqueous solution and soluble in an alkaline aqueous solution by the action of an acid, an acid generator, and the formula (I) A resist composition containing the compound.

[In Formula (I), R ¹ , R ² and R ³ each independently represents an alkyl group having 1 to 6 carbon atoms.
s, t, and u each independently represent an integer of 0 to 3. When s is an integer of 2 or more, the plurality of R ¹ may be the same or different, and when t is an integer of 2 or more, the plurality of R ² may be the same or different. Well, when u is an integer of 2 or more, the plurality of R ³ may be the same or different, and when n is an integer of 2 or more, the plurality of t are the same or different. Also good.
n represents an integer of 1 to 3. ]

［式（Ｂ１）中、
Ｑ¹及びＱ²は、それぞれ独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｌ^b1は、単結合又は炭素数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−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｙは、置換基を有していてもよい炭素数１〜１８の脂肪族炭化水素基又は置換基を有していてもよい炭素数３〜１８の飽和環状炭化水素基を表し、該脂肪族炭化水素基及び該飽和環状炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＳＯ_２−又は−ＣＯ−で置き換わっていてもよい。
Ｚ⁺は、有機カチオンを表す。］ [2] The resist composition according to [1], wherein the acid generator is an acid generator represented by the formula (B1).

[In the formula (B1),
Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and —CH ₂ — contained in the divalent saturated hydrocarbon group is replaced by —O— or —CO—. May be.
Y represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent or a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, and the aliphatic group —CH ₂ — contained in the hydrocarbon group and the saturated cyclic hydrocarbon group may be replaced by —O—, —SO ₂ — or —CO—.
Z ⁺ represents an organic cation. ]

[3] The resist composition according to [2], wherein L ^b1 is * —CO—O— (* represents a bond with —C (Q ¹ ) (Q ² ) —).

[4] The resist composition according to [2] or [3], wherein Z ⁺ is an arylsulfonium cation.

[5] The resist composition according to any one of [1] to [4], further containing a nitrogen-containing basic compound.

[6] (1) A step of applying the resist composition according to any one of [1] to [5] 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 step of developing the heated composition layer using a developing device;
A method for producing a resist pattern including:

  The resist composition of the present invention has a wide focus margin when forming a resist pattern.

  The resist composition of the present invention has an acid labile group, is insoluble or hardly soluble in an aqueous alkali solution, can be dissolved in an aqueous alkaline solution by the action of an acid, an acid generator, And a compound represented by I).

<Resin (hereinafter sometimes referred to as “resin (A)”)>
Resin (A) is a resin that becomes alkali-soluble by the action of an acid. A resin that becomes alkali-soluble by the action of an acid can be produced by polymerizing a monomer having an acid-labile group (hereinafter sometimes referred to as “monomer having an acid-labile group (a1)”), It becomes alkali-soluble by the action of acid. The phrase “becomes soluble in an alkali by the action of an acid” means “being insoluble or hardly soluble in an alkaline aqueous solution before contact with an acid, but soluble in an alkaline aqueous solution after contact with an acid”. . As the monomer (a1) having an acid labile group, one type may be used alone, or two or more types may be used in combination.

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

式（１）中、Ｒ^a1〜Ｒ^a3は、それぞれ独立に、炭素数１〜８の脂肪族炭化水素基又は炭素数３〜２０の飽和環状炭化水素基を表すか或いはＲ^a1及びＲ^a2は互いに結合して炭素数３〜２０の環を形成する。＊は結合手を表す（以下同じ）。

In the formula (1), R ^{a1 to} R ^a3 each independently represent an aliphatic hydrocarbon group having 1 to 8 carbon atoms or a saturated cyclic hydrocarbon group having 3 to 20 carbon atoms, or R ^a1 and R ^a2 are Bond to each other to form a ring having 3 to 20 carbon atoms. * Represents a bond (same below).

式（１）における飽和環状炭化水素基の炭素数は、好ましくは炭素数３〜１６である。 Examples of the aliphatic hydrocarbon group include an alkyl group, and examples thereof 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 saturated cyclic hydrocarbon group may be monocyclic or polycyclic, and examples of the monocyclic saturated cyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, and dimethylcyclohexyl. Cycloalkyl groups such as a group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic saturated hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, methylnorbornyl group, and the following groups.

Carbon number of the saturated cyclic hydrocarbon group in Formula (1) becomes like this. Preferably it is C3-C16.

When R ^a1 and R ^a2 are bonded to each other to form a ring, examples of the —C (R ^a1 ) (R ^a2 ) (R ^a3 ) group include the following groups. The number of carbon atoms in the ring is preferably 3 to 12 carbon atoms.

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

The monomer (a1) having an acid labile group is preferably a monomer having an acid labile group (1) and a carbon-carbon double bond, more preferably an acid labile group (1). (Meth) acrylic monomer having In the present specification, the "(meth) acrylic monomer" means at least one monomer having a "CH ₂ = CH-CO-" or _{"CH 2 = C (CH 3)} -CO- " structure of To do. 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.

  Among the (meth) acrylic monomers having the acid-labile group (1), those having a saturated cyclic hydrocarbon group having 5 to 20 carbon atoms are preferred. Further, among the monomers (a1) having an acid labile group, if a resin obtained by polymerizing a monomer (a1) having a bulky structure such as a saturated cyclic hydrocarbon group is used, the resolution of the resist can be improved. Can be improved.

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

［式（ａ１−１）及び式（ａ１−２）中、
Ｌ^a1及びＬ^a2は、それぞれ独立に、−Ｏ−又は^＊−Ｏ−（ＣＨ₂）_k1−ＣＯ−Ｏ−を表す。
ｋ１は１〜７の整数を表す。＊は−ＣＯ−との結合手を表す。
Ｒ^a4及びＲ^a5は、それぞれ独立に、水素原子又はメチル基を表す。
Ｒ^a6及びＲ^a7は、それぞれ独立に、炭素数１〜８の脂肪族炭化水素基又は炭素数３〜２０の飽和環状炭化水素基を表す。
ｍ１は０〜１４の整数を表す。
ｎ１は０〜１０の整数を表す。］

[In Formula (a1-1) and Formula (a1-2),
L ^a1 and L ^a2 each independently represent —O— or ^* —O— (CH ₂ ) _k1 —CO—O—.
k1 represents an integer of 1 to 7. * Represents a bond with -CO-.
R ^a4 and R ^a5 each independently represent a hydrogen atom or a methyl group.
R ^a6 and R ^a7 each independently represent an aliphatic hydrocarbon group having 1 to 8 carbon atoms or a saturated cyclic hydrocarbon group having 3 to 20 carbon atoms.
m1 represents the integer of 0-14.
n1 represents an integer of 0 to 10. ]

ｍ１は、好ましくは０〜３の整数、より好ましくは０又は１である。
ｎ１は、好ましくは０〜３の整数、より好ましくは０又は１である。 L ^a1 and L ^a2 are preferably —O— or ^* —O— (CH ₂ ) _f1 —CO—O— (wherein f1 represents an integer of 1 to 4), more preferably —O—. It is. k1 is preferably an integer of 1 to 4, more preferably 1.
R ^a4 and R ^a5 are preferably methyl groups.
Examples of the aliphatic hydrocarbon group for R ^a6 and R ^a7 include an alkyl group, and examples thereof 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 aliphatic hydrocarbon group represented by R ^a6 and R ^a7 preferably has 6 or less carbon atoms. The saturated cyclic hydrocarbon group preferably has 8 or less carbon atoms, more preferably 6 or less.
The saturated cyclic hydrocarbon group for R ^a6 and R ^a7 may be either monocyclic or polycyclic. Examples of the monocyclic saturated cyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, and a methylcyclohexyl group. Cycloalkyl groups such as a group, dimethylcyclohexyl group, cycloheptyl group, and cyclooctyl group. Examples of the polycyclic saturated hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, methylnorbornyl group, and the following groups.

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.

  Examples of the monomer represented by the formula (a1-1) include the following. Among them, 2-methyladamantan-2-yl (meth) acrylate, 2-ethyladamantan-2-yl (meth) acrylate and 2-isopropyladamantan-2-yl (meth) acrylate are preferable, and 2-methyladamantan-2-yl Il methacrylate, 2-ethyladamantan-2-yl methacrylate and 2-isopropyladamantan-2-yl methacrylate are more preferred.

  Examples of the monomer represented by the formula (a1-2) include the following. Among these, 1-ethylcyclohexane-1-yl (meth) acrylate is preferable, and 1-ethylcyclohexane-1-yl methacrylate is more preferable.

  When the resin (A) includes a structural unit derived from the monomer represented by the formula (a1-1) or the monomer represented by the formula (a1-2), the total content thereof is the total of the resin (A). It is 10-95 mol% normally with respect to a structural unit, Preferably it is 15-90 mol%, More preferably, it is 20-85 mol%, More preferably, it is 25-60 mol%.

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

［式（ａ１−３）中、
Ｒ^a9は、水素原子、ヒドロキシ基を有していてもよい炭素数１〜３の脂肪族炭化水素基、カルボキシ基、シアノ基又は炭素数１〜８のアルコキシカルボニル基（−ＣＯＯＲ^a13）を表し、Ｒ^a13は、炭素数１〜８の脂肪族炭化水素基又は炭素数３〜２０の飽和環状炭化水素基を表し、該脂肪族炭化水素基及び該飽和環状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飽和環状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^a10〜Ｒ^a12は、それぞれ独立に、炭素数１〜１２の脂肪族炭化水素基又は炭素数３〜２０の飽和環状炭化水素基を表すか、或いはＲ^a10及びＲ^a11は互いに結合して炭素数３〜２０の環を形成し、該脂肪族炭化水素基及び該飽和環状炭化水素基に含まれる水素原子はヒドロキシ基等で置換されていてもよく、該脂肪族炭化水素基及び該飽和環状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。］

[In the formula (a1-3),
R ^a9 represents a hydrogen atom, a C 1-3 aliphatic hydrocarbon group that may have a hydroxy group, a carboxy group, a cyano group, or a C 1-8 alkoxycarbonyl group (—COOR ^a13 ). , R ^a13 represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms or a saturated cyclic hydrocarbon group having 3 to 20 carbon atoms, and the hydrogen atoms contained in the aliphatic hydrocarbon group and the saturated cyclic hydrocarbon group are It may be substituted with a hydroxy group, and —CH ₂ — contained in the aliphatic hydrocarbon group and the saturated cyclic hydrocarbon group may be replaced with —O— or —CO—.
R ^{a10 to} R ^a12 each independently represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms or a saturated cyclic hydrocarbon group having 3 to 20 carbon atoms, or R ^a10 and R ^a11 are bonded to each other to form carbon. A hydrogen atom contained in the aliphatic hydrocarbon group and the saturated cyclic hydrocarbon group that forms a ring of several 3 to 20 may be substituted with a hydroxy group, etc., and the aliphatic hydrocarbon group and the saturated cyclic group —CH ₂ — contained in the hydrocarbon group may be replaced by —O— or —CO—. ]

  Here, examples of the alkoxycarbonyl group include groups in which a carbonyl group is bonded to an alkoxy group such as a methoxycarbonyl group or an ethoxycarbonyl group.

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

  Examples of the monomer represented by the formula (a1-3) include, for example, 5-norbornene-2-carboxylic acid-tert-butyl, 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, 5-norbornene- 1-methylcyclohexyl 2-carboxylate, 2-methyl-2-adamantyl 5-norbornene-2-carboxylate, 2-ethyl-2-adamantyl 5-norbornene-2-carboxylate, 5-norbornene-2-carboxylic acid 1 -(4-Methylcyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1- (4-hydroxycyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1-methyl-1- ( 4-oxocyclohexyl) ethyl, 1- (1-adamantyl) 5-norbornene-2-carboxylate And 1-methyl-ethyl.

  When the resin (A) includes a structural unit derived from the monomer represented by the formula (a1-3), the content thereof is usually 10 to 95 mol% with respect to all the structural units of the resin (A). , Preferably it is 15-90 mol%, More preferably, it is 20-85 mol%.

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

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

Examples of the alkyl group that may have a halogen atom include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, and a perfluoropentyl group. Perfluorohexyl group, perchloromethyl group, perbromomethyl group, periodomethyl group and the like.
Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentoxy group, and an n-hexoxy group. .
Examples of the acyl group include acetyl, propionyl, butyryl and the like.
Examples of the acyloxy group include acetyloxy, propionyloxy, butyryloxy and the like.
Examples of the hydrocarbon group include an aliphatic hydrocarbon group, a saturated cyclic hydrocarbon group, and an aromatic hydrocarbon group.
Aromatic hydrocarbon groups include phenyl, naphthyl, anthryl, p-methylphenyl, p-tert-butylphenyl, p-adamantylphenyl, tolyl, xylyl, cumenyl, mesityl, biphenyl Groups, anthryl groups, phenanthryl groups, 2,6-diethylphenyl groups, aryl groups such as 2-methyl-6-ethylphenyl, and the like.

The alkyl group for R ¹⁰ and R ¹¹ preferably has 1 to 4 carbon atoms, more preferably 1 or 2 carbon atoms, and particularly preferably a methyl group.
As the alkoxy group for R ¹¹ , C 1 or 2 is more preferable, and a methoxy group is particularly preferable.
Examples of the hydrocarbon group for R ¹² and R ¹³ include isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, 2-ethylhexyl group, cyclohexyl group, adamantyl group, A 2-alkyladamantan-2-yl group, a 1- (1-adamantyl) -1-alkyl group, an isobornyl group, and the like are preferable.
The substituent that X ^a2 and Y ^a3 may have is preferably a hydroxy group.

  Examples of the monomer represented by the formula (a1-4) include the following monomers.

  When the resin (A) includes a structural unit derived from the monomer represented by the formula (a1-4), the content is usually 10 to 95 mol% with respect to all the structural units of the resin (A). , Preferably it is 15-90 mol%, More preferably, it is 20-85 mol%.

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

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

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

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

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

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

Examples of the alkyl group for R ⁸ 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, an n-pentyl group, and an n-hexyl group. An alkyl group having 1 to 4 carbon atoms is preferable, an alkyl group having 1 or 2 carbon atoms is more preferable, and a methyl group is particularly preferable.
Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentoxy group, and an n-hexoxy group. , An alkoxy group having 1 to 4 carbon atoms is preferable, an alkoxy group having 1 or 2 carbon atoms is more preferable, and a methoxy group is particularly preferable.
ma is preferably 0 to 2, more preferably 0 or 1, and particularly preferably 0.

When obtaining a copolymer resin having a structural unit derived from a monomer having such a phenolic hydroxy group, radical polymerization of the corresponding (meth) acrylic acid ester monomer, acetoxystyrene, and styrene is followed by deacetylation with an acid. Can be obtained.
Examples of the monomer having a phenolic hydroxy group include the following monomers.

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

  When the resin (A) includes a structural unit derived from the monomer represented by the formula (a2-0), the content is usually 5 to 90 mol% with respect to all the structural units of the resin (A). , Preferably it is 10-85 mol%, More preferably, it is 15-80 mol%.

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

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。

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.

  As an acid stable monomer (a2-1) which has a hydroxyadamantyl group, the following are mentioned, for example. Among them, 3-hydroxyadamantan-1-yl (meth) acrylate, 3,5-dihydroxyadamantan-1-yl (meth) acrylate and (meth) acrylic acid 1- (3,5-dihydroxy-adamantan-1-yloxy Carbonyl) methyl is preferred, 3-hydroxyadamantan-1-yl (meth) acrylate and 3,5-dihydroxyadamantan-1-yl (meth) acrylate are more preferred, 3-hydroxyadamantan-1-yl methacrylate and 3,5 -Dihydroxyadamantan-1-yl methacrylate is more preferred.

  When the resin (A) includes a structural unit derived from the monomer represented by the formula (a2-1), the content is usually 3 to 40 mol% with respect to all the structural units of the resin (A). , Preferably it is 5-35 mol%, More preferably, it is 5-30 mol%.

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

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

式（ａ３−１）〜式（ａ３−３）中、
Ｌ^a4〜Ｌ^a6は、それぞれ独立に、−Ｏ−又は^＊−Ｏ−（ＣＨ₂）_k3−ＣＯ−Ｏ−を表す。
ｋ３は１〜７の整数を表す。＊は−ＣＯ−との結合手を表す。
Ｒ^a18〜Ｒ^a20は、それぞれ独立に、水素原子又はメチル基を表す。
Ｒ^a21は、炭素数１〜４の脂肪族炭化水素基を表す。
ｐ１は０〜５の整数を表す。
Ｒ^a22及びＲ^a23は、それぞれ独立に、カルボキシ基、シアノ基又は炭素数１〜４の脂肪族炭化水素基を表す。
ｑ１及びｒ１は、それぞれ独立に０〜３の整数を表す。ｐ１、ｑ１又はｒ１が２以上のとき、それぞれ、複数のＲ^a21、Ｒ^a22又はＲ^a23は、互いに同一でも異なってもよい。

In formula (a3-1) to formula (a3-3),
L ^{a4 to} L ^a6 each independently represent —O— or ^* —O— (CH ₂ ) _k3 —CO—O—.
k3 represents an integer of 1 to 7. * Represents a bond with -CO-.
R ^{a18 to} R ^a20 each independently represents a hydrogen atom or a methyl group.
R ^a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
p1 represents an integer of 0 to 5.
R ^a22 and R ^a23 each independently represent a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms.
q1 and r1 each independently represents an integer of 0 to 3. When p1, q1 or r1 is 2 or more, a plurality of R ^a21 , R ^a22 or R ^a23 may be the same as or different from each other.

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

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

  Examples of the acid-stable monomer (a3-1) having a γ-butyrolactone ring that serve as an acid-labile monomer include the following.

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

  Among the acid stable monomers (a3-2) having a condensed ring of γ-butyrolactone ring and norbornane ring, the following can be exemplified as those that function as acid labile monomers.

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

  Among the monomers (a3-3) having a condensed ring of a γ-butyrolactone ring and a cyclohexane ring, examples of those that function as acid labile monomers include the following.

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

  When the resin (A) contains a structural unit derived from the monomer represented by the formula (a3-1), the formula (a3-2) or the formula (a3-3), these contents are the same as those of the resin (A). It is usually 5 to 70 mol%, preferably 10 to 65 mol%, more preferably 5 to 50 mol%, still more preferably 10 to 45 mol%, and more preferably to all structural units. Preferably it is 15-40 mol%.

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

式（ａ４−３）中、
Ｒ^a25及びＲ^a26は、それぞれ独立に、水素原子、ヒドロキシ基を有していてもよい炭素数１〜３の脂肪族炭化水素基、シアノ基、カルボキシ基又はアルコキシカルボニル基（−ＣＯＯＲ^a27）を表すか、或いはＲ^a25及びＲ^a26は互いに結合して−ＣＯ−Ｏ−ＣＯ−を形成し、
Ｒ^a27は、炭素数１〜１８の脂肪族炭化水素基又は炭素数３〜１８の飽和環状炭化水素基を表し、脂肪族炭化水素基及び飽和環状炭化水素基の−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。但し−ＣＯＯＲ^a27が酸不安定基となるものは除く（即ちＲ^a27は、３級炭素原子が−Ｏ−と結合するものを含まない）。

In formula (a4-3),
R ^a25 and R ^a26 each independently represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 3 carbon atoms which may have a hydroxy group, a cyano group, a carboxy group or an alkoxycarbonyl group (—COOR ^a27 ). R ^a25 and R ^a26 combine with each other to form —CO—O—CO—,
R ^a27 represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms or a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms, and —CH ₂ — of the aliphatic hydrocarbon group and the saturated cyclic hydrocarbon group is —O _2. -Or -CO- may be substituted. However, those in which —COOR ^a27 is an acid labile group are excluded (that is, R ^a27 does not include those in which a tertiary carbon atom is bonded to —O—).

^Examples of the aliphatic hydrocarbon group which may have a hydroxyl group for R ^a25 and R ^a26 include a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, and a 2-hydroxyethyl group.
The aliphatic hydrocarbon group for R ^a27 preferably has 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms. The saturated cyclic hydrocarbon group preferably has 4 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.
^Examples of R ^a27 include a methyl group, an ethyl group, a propyl group, a 2-oxo-oxolan-3-yl group, and a 2-oxo-oxolan-4-yl group.

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

  When resin contains the structural unit derived from the monomer represented by Formula (a4-1), Formula (a4-2), or Formula (a4-3), these content is the total structure of resin (A), respectively. It is 2-40 mol% normally with respect to a unit, Preferably it is 3-30 mol%, More preferably, it is 5-20 mol%.

［式（ａ５）中、
Ｔは、炭素数４〜３６の飽和環状炭化水素基を表し、該飽和環状炭化水素基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７〜１３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、該飽和環状炭化水素基に含まれる−ＣＨ_２−は、少なくとも１つの−ＳＯ_２−で置き換わっており、さらに、−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^ａ２９）−で置き換わっていてもよい。
Ｒ^ａ２９は、水素原子又は炭素数１〜６のアルキル基を表す。
Ｒ^ａ２８は、水素原子、ハロゲン原子また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、置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は、−ＣＯ−、−Ｏ−、−Ｓ−又は−Ｎ（Ｒ^ｃ）−で置き換わっていてもよい。
ｎ４は、０又は１の整数を表す。］ <Monomer (a5) having a sultone ring>
The monomer (a5) having a sultone ring is represented, for example, by the formula (a5). The monomer (a5) having a sultone ring can be produced by a method known in the art.

[In the formula (a5),
T represents a saturated cyclic hydrocarbon group having 4 to 36 carbon atoms, and the hydrogen atom contained in the saturated cyclic hydrocarbon group is a halogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or a carbon atom having 1 to 12 carbon atoms. It may be substituted with an alkoxy group, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, a glycidyloxy group or an acyl group having 2 to 4 carbon atoms, and is included in the saturated cyclic hydrocarbon group —CH ₂ — is replaced by at least one —SO ₂ —, and may be further replaced by —CO—, —O—, ^—S— , —SO ₂ — or —N (R ^a29 ) —. .
R ^a29 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
R ^a28 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 C 1-17 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —CO—, —O—, —S. -Or -N ( ^Rc )-may be substituted.
n4 represents an integer of 0 or 1. ]

Examples of the saturated cyclic 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, a 2-adamantyl group, And cycloalkyl groups such as isobornyl group.
Examples of the halogen atom include fluorine, chlorine, bromine and iodine atoms.

  Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, heptyl group, 2 -Ethylhexyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, etc. are mentioned.

  As an alkoxy group, a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentoxy group, an n-hexoxy group, a heptoxy group, an octoxy group , 2-ethylhexoxy group, nonyloxy group, decyloxy group, undecyloxy group, dodecyloxy group and the like.

Examples of the aryl group include a phenyl group, a naphthyl group, an anthranyl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group; a tolyl group, a xylyl group, a cumenyl group, a mesityl group, and a biphenyl group. , Anthryl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl and the like.
Examples of the aralkyl group include benzyl group, phenethyl group, phenylpropyl group, trityl group, naphthylmethyl group, naphthylethyl group and the like.
Examples of the acyl group include an acetyl group, a propionyl group, and a butyryl group.

  Examples of the saturated hydrocarbon group include a linear or branched alkylene 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, tert-butylene group, propylidene group, etc. Can be mentioned.

T is preferably a group represented by the formula (T0), and more preferably a group represented by the formula (T0a).
T is preferably a group represented by the formula (T1), and is preferably a group represented by the formula (T1a).

［式（Ｔ０）、式（Ｔ０ａ）、式（Ｔ１）及び式（Ｔ１ａ）中、
環に含まれる水素原子は、ハロゲン原子、ヒドロキシ基、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７〜１３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、該飽和環状炭化水素基に含まれる−ＣＨ_２−は、少なくとも１つの−ＳＯ_２−で置き換わっており、さらに、−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^ａ２９）−で置き換わっていてもよい。
Ｒ^ａ２９は、上記と同じ意味を表す。
＊は、酸素原子との結合手を表す。
Ｔ^１は、−Ｏ−又は−ＣＨ_２−を表す。］

[In Formula (T0), Formula (T0a), Formula (T1), and Formula (T1a),
The hydrogen atom contained in the ring is a halogen atom, a hydroxy 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 13 carbon atoms, It may be substituted with a glycidyloxy group or an acyl group having 2 to 4 carbon atoms, and —CH ₂ — contained in the saturated cyclic hydrocarbon group is replaced with at least one —SO ₂ —, and ^CO—, —O—, ^—S— , —SO ₂ — or —N (R ^a29 ) — may be ^substituted .
R ^a29 represents the same meaning as described above.
* Represents a bond with an oxygen atom.
T ¹ represents —O— or —CH ₂ —. ]

［式（Ｔ２）及び式（Ｔ２ａ）中、
環に含まれる水素原子は、ハロゲン原子、ヒドロキシ基、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７〜１３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、該飽和環状炭化水素基に含まれる−ＣＨ_２−は、−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−又は−Ｎ（Ｒ^ａ２９）−で置き換わっていてもよい。
Ｒ^ａ２９は、上記と同じ意味を表す。
＊は、酸素原子との結合手を表す。］ Furthermore, T is preferably a group represented by the formula (T2), and more preferably a group represented by the formula (T2a).

[In Formula (T2) and Formula (T2a),
The hydrogen atom contained in the ring is a halogen atom, a hydroxy 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 13 carbon atoms, It may be substituted with a glycidyl group or an acyl group having 2 to 4 carbon atoms, _-CH 2 contained in the saturated cyclic hydrocarbon group - is, -CO -, - O -, - S -, - SO 2 ^-Or -N (R ^a29 ) ^{-may be substituted} .
R ^a29 represents the same meaning as described above.
* Represents a bond with an oxygen atom. ]

R ^a28 is preferably a hydrogen atom or a methyl group.
Z ^{a1 is,} -CH ₂ contained in ^{Z a1} - is, -O -, - CO -, - S- or -N ^{(R a29)} - been substituted with are preferred. R ^a29 is preferably a hydrogen atom.
For example, -O-X ^a11- , -X ^a11 -O-, -X ^a11 -CO-O-, -X ^a11 -O- ^CO- , -X ^a11 -O-X ^a12- , ^-NH -X ^a11- , —X ^a11 —NH— and the like, preferably —O—X ^a11 —, —X ^a11 —O—, —X ^a11 —CO—O—, —NH—X ^a11 —, —X ^a11 —NH— More preferably, -O- ^Xa11- , -NH- ^Xa11-, etc. are mentioned. In particular, it is more preferable that Z ^a1 is —O—CH ₂ —.
Here, X ^a11 and X ^a12 each independently represent a single bond, a linear or branched alkanediyl group having 1 to 15 carbon atoms. However, in the group in which —CH ₂ — contained in the alkanediyl group is replaced, the number of atoms constituting the main chain of each of the above groups is suitably 1 to 17, preferably 1 to 10, and 1 to 5 More preferred.

Ｔとしては、例えば、下記のもの等が例示される。＊は酸素原子との結合手を示す。

Examples of T include the following. * Indicates a bond with an oxygen atom.

  Examples of the monomer represented by the formula (a5) include the following compounds.

  When the resin (A) contains a structural unit derived from the monomer represented by the formula (a5), the content thereof is usually 2 to 40 mol% with respect to all the structural units of the resin (A), preferably Is 3 to 30 mol%, more preferably 5 to 20 mol%.

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

The weight average molecular weight of the resin (A) is preferably 2,500 or more (more preferably 3,000 or more, more preferably 3,500 or more), 50,000 or less (more preferably 30,000 or less, and further preferably Is 10,000 or less).
It is preferable that content of resin (A) is 80 to 99 mass% in solid content of a composition.
In the present specification, the “solid content in the composition” means the total of resist composition components excluding the solvent (E) described later. The solid content in the composition and the content of the resin (A) relative thereto can be measured by a known analysis means such as liquid chromatography or gas chromatography.

<Acid generator (hereinafter sometimes referred to as "acid generator (B)")>
The acid generator (B) is classified into a nonionic type and an ionic type. Nonionic acid generators include organic halides, sulfonate esters (for example, 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4). -Sulfonates), sulfones (e.g. disulfone, ketosulfone, sulfonyldiazomethane) and the like. The ionic acid generator is typically an onium salt containing an onium cation (for example, diazonium salt, phosphonium salt, sulfonium salt, iodonium salt). Examples of the anion of the onium salt include a sulfonate anion, a sulfonylimide anion, and a sulfonylmethide anion.

  Examples of the acid generator (B) include not only an acid generator (particularly a photoacid generator) used in the resist field, but also a photoinitiator for photocationic polymerization, a photodecolorant for dyes, or a photochromic agent. Known compounds that generate an acid by radiation (light) and mixtures thereof can also be used as appropriate. For example, JP-A 63-26653, JP-A 55-164824, JP-A 62-69263, JP-A 63-146038, JP-A 63-163452, JP-A 62-153853, Acid can be obtained by radiation described in Japanese Utility Model Laid-Open No. 63-146029, U.S. Pat. No. 3,779,778, U.S. Pat. The resulting compound can be used.

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

［式（Ｂ１）中、
Ｑ¹及びＱ²は、それぞれ独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｌ^b1は、単結合又は炭素数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−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｙは、置換基を有していてもよい炭素数１〜１８の脂肪族炭化水素基又は置換基を有していてもよい炭素数３〜１８の飽和環状炭化水素基を表し、該脂肪族炭化水素基及び該飽和環状炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＳＯ_２−又は−ＣＯ−で置き換わっていてもよい。
Ｚ⁺は、有機カチオンを表す。］

[In the formula (B1),
Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and —CH ₂ — contained in the divalent saturated hydrocarbon group is replaced by —O— or —CO—. May be.
Y represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent or a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, and the aliphatic group —CH ₂ — contained in the hydrocarbon group and the saturated cyclic hydrocarbon group may be replaced by —O—, —SO ₂ — or —CO—.
Z ⁺ represents an organic cation. ]

Examples of the perfluoroalkyl group include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. Can be mentioned.
In formula (B1), 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 include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic divalent saturated cyclic hydrocarbon group, and two of these groups. A combination of the above may also 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, Linear alkanediyl groups such as 17-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group, propane-2,2-diyl group;
On the side of 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) Having a chain, for example, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, Branched alkanediyl groups such as 2-methylbutane-1,4-diyl group;
In cycloalkanediyl groups such as cyclobutane-1,3-diyl group, 1,3-cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group silene group, cyclooctane-1,5-diyl group, etc. A monocyclic divalent saturated cyclic hydrocarbon group;
Polycyclic divalent saturated ring such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, 1,5-adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. A hydrocarbon group etc. are mentioned.

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

式（ｂ１−１）〜式（ｂ１−６）中、
Ｌ^b2は、単結合又は炭素数１〜１５の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。
中でも、式（ｂ１−１）で表される２価の基が好ましく、Ｌ^b2が単結合又は−ＣＨ_２−である式（ｂ１−１）で表される２価の基がより好ましい。

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 divalent saturated hydrocarbon group having 1 to 13 carbon atoms. However, the upper limit of the carbon number of L ^b3 and L ^b4 is 13.
L ^b5 represents a 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.
L ^b8 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms.
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, a divalent group represented by the formula (b1-1) is preferable, and a divalent group represented by the formula (b1-1) in which L ^b2 is a single bond or —CH ₂ — is more preferable.

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

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

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

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

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

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

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

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

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

  Especially, it is preferably a group represented by any one of formulas (Y1) to (Y19), more preferably represented by formula (Y11), formula (Y14), formula (Y15) or formula (Y19). And more preferably a group represented by formula (Y11) or formula (Y14).

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

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

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

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

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

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

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

As the sulfonate anion containing Y which is a saturated cyclic hydrocarbon group substituted with — (CH ₂ ) _j2 —O—CO—R ^b1 group and a divalent group represented by the formula (b1-1), For example, the following are mentioned.

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

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

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

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

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

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

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

As the sulfonate anion containing Y which is a saturated cyclic hydrocarbon group substituted with — (CH ₂ ) _j2 —O—CO—R ^b1 group and a divalent group represented by the formula (b1-2), For example, the following are mentioned.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Among these, the following sulfonate anions having a divalent group represented by the formula (b1-1) are more preferable.

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

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

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

R ^b7 and R ^b8 each independently represent a hydroxy group, an 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 an integer of 2 or more, the plurality of R ^b7 are the same or different from each other, and when n2 is an integer of 2 or more, the plurality of R ^b8 are the same or different from each other.

R ^b9 and R ^b10 each independently represent an aliphatic hydrocarbon group having 1 to 18 carbon atoms or a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms.
R ^b11 represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.
The aliphatic hydrocarbon group of R ^{b9 to} R ^b11 preferably has 1 to 12 carbon atoms, and the saturated cyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.
R ^b12 represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. The aromatic hydrocarbon group is an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms, or an alkylcarbonyloxy having 1 to 12 carbon atoms. It may be substituted with a group.
R ^b9 and R ^b10 , and R ^b11 and R ^b12 may be independently bonded to each other to form a 3- to 12-membered ring (preferably a 3- to 7-membered ring), These rings —CH ₂ — may be replaced by —O—, —S— or —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 an integer of 2 or more, the plurality of R ^b13 are the same or different, and when p2 is an integer of 2 or more, the plurality of R ^b14 are the same or different, and q2 is 2 or more. when an integer multiple of R ^b15 are different phases or the same as each other, when r2 is an integer of 2 or more, or different and are a plurality of R ^b16 are identical to each other, s2 is 2 or more integer When the plurality of R ^b17 are the same or different, and when t2 is an integer of 2 or more, the plurality of R ^b18 are the same or different.

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

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

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

式（ｂ２−１−１）中、
Ｒ^b19〜Ｒ^b21は、それぞれ独立に、ハロゲン原子（より好ましくはフッ素原子）、ヒドロキシ基、炭素数１〜１８の脂肪族炭化水素基、炭素数３〜１８の飽和環状炭化水素基又は炭素数１〜１２のアルコキシ基を表す。
脂肪族炭化水素基は、好ましくは炭素数１〜１２であり、飽和環状炭化水素基は、好ましくは炭素数４〜１８である。
前記脂肪族炭化水素基は、ヒドロキシ基、炭素数１〜１２のアルコキシ基又は炭素数６〜１８の芳香族炭化水素基で置換されていてもよい。
前記飽和環状炭化水素基は、ハロゲン原子、炭素数２〜４のアシル基又はグリシジルオキシ基で置換されていてもよい。
ｖ２、ｗ２及びｘ２は、それぞれ独立に０〜５の整数（好ましくは０又は１）を表す。ｖ２が２以上の整数であるとき、複数のＲ^b19は互いに同一であるか相異なり、ｗ２が２以上の整数であるとき、複数のＲ^b20は互いに同一であるか相異なり、ｘ２が２以上の整数であるとき、複数のＲ^b21は互いに同一であるか相異なる。
なかでも、Ｒ^b19〜Ｒ^b21は、それぞれ独立に、好ましくは、ハロゲン原子（より好ましくはフッ素原子）、ヒドロキシ基、炭素数１〜１２のアルキル基、又は炭素数１〜１２のアルコキシ基である。

In formula (b2-1-1),
R ^{b19 to} R ^b21 each independently represent a halogen atom (more preferably a fluorine atom), a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms, or a carbon number. 1 to 12 alkoxy groups are represented.
The aliphatic hydrocarbon group preferably has 1 to 12 carbon atoms, and the saturated cyclic hydrocarbon group preferably has 4 to 18 carbon atoms.
The aliphatic hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.
The saturated cyclic hydrocarbon group may be substituted with a halogen atom, an acyl group having 2 to 4 carbon atoms, or a glycidyloxy group.
v2, w2 and x2 each independently represent an integer of 0 to 5 (preferably 0 or 1). When v2 is an integer of 2 or more, the plurality of R ^b19 are the same or different, and when w2 is an integer of 2 or more, the plurality of R ^b20 are the same or different, and x2 is 2 or more. The plurality of R ^b21 are the same as or different from each other.
Among them, R ^{b19 to} R ^b21 are preferably each independently a halogen atom (more preferably a fluorine atom), a hydroxy group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. .

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

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

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

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

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

  Preferred acid generators (B1) are those represented by formula (B1-1) to formula (B1-17). Among them, acid generators (B1-1), (B1-2), (B1-6), (B1-11), (B1-12), (B1-13) and (B1-14) containing a triphenylsulfonium cation ) And (B1-3) are more preferable.

  The content of the acid generator (B) is preferably 1 part by mass or more (more preferably 3 parts by mass or more, more preferably 5 parts by mass or more), preferably 30 parts by mass with respect to 100 parts by mass of the resin (A). Part or less (more preferably 25 parts by weight or less, and still more preferably 20 parts by weight or less).

［式（Ｉ）中、Ｒ^１〜Ｒ^３は、それぞれ独立に、炭素数１〜６のアルキル基を表す。
ｓ、ｔ及びｕは、それぞれ独立に、０〜３の整数を表す。ｓが２以上の整数であるとき、複数のＲ^１は同一であっても異なっていてもよく、ｔが２以上の整数であるとき、複数のＲ^２は同一であっても異なっていてもよく、ｕが２以上の整数であるとき、複数のＲ^３は同一であっても異なっていてもよく、ｎが２以上の整数であるとき、複数のｔは同一であっても異なっていてもよい。
ｎは１〜３の整数を表す。］ <Compound represented by formula (I)>
The resist composition of the present invention contains a compound represented by the formula (I). As a result, the resist composition of the present invention has an effect that the focus margin when forming the pattern is wide.

[In Formula (I), R < ¹ > -R < ³ > represents a C1-C6 alkyl group each independently.
s, t, and u each independently represent an integer of 0 to 3. When s is an integer of 2 or more, the plurality of R ¹ may be the same or different, and when t is an integer of 2 or more, the plurality of R ² may be the same or different. Well, when u is an integer of 2 or more, the plurality of R ³ may be the same or different, and when n is an integer of 2 or more, the plurality of t are the same or different. Also good.
n represents an integer of 1 to 3. ]

Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. An alkyl group having 1 to 4 carbon atoms is preferable, an alkyl group having 1 or 2 carbon atoms is more preferable, and a methyl group is particularly preferable.
As the compound represented by the formula (I), a compound represented by the formula (I-1) is preferable, and a compound represented by the formula (I-2) is more preferable.
Moreover, the compound represented by Formula (I-1 ′) is preferable, the compound represented by Formula (I-2 ′) is more preferable, and the compound represented by Formula (I-3) and Formula (I-4) are preferred. ) Is particularly preferred.

［式（Ｉ−１）中、ｎは上記と同じ意味を表す。］

[In formula (I-1), n represents the same meaning as described above. ]

［式（Ｉ−２）中、ｎは上記と同じ意味を表す。］

[In formula (I-2), n represents the same meaning as described above. ]

［式（Ｉ−１’）中、ｎは上記と同じ意味を表す。ａ及びｂは、互いに独立に、０又は１を表す。］

[In formula (I-1 ′), n represents the same meaning as described above. a and b represent 0 or 1 independently of each other. ]

［式（Ｉ−２’）中、ｎは上記と同じ意味を表す。ａ及びｂは、互いに独立に、０又は１を表す。］

[In formula (I-2 ′), n represents the same meaning as described above. a and b represent 0 or 1 independently of each other. ]

The compound represented by the formula (I) can be produced by a known production method, for example, by the method described in JP-A-6-167805.
The content of the compound represented by the formula (I) is preferably 0.01 to 1% by mass, more preferably 0.05 to 0.95% by mass, based on the solid content of the resist composition. It is preferable that the content of the compound represented by formula (I) is within the above range because a focus margin tends to be wide when forming a pattern.

<Basic compound (hereinafter sometimes referred to as “basic compound (C)”)>
The resist composition of the present invention preferably contains a basic compound (C). The “basic compound” as used herein means a compound having a property of capturing an acid, particularly a compound having a property of capturing an acid generated from the above-described acid generator.
When the basic compound (C) is contained, the content thereof is preferably about 0.01 to 1% by mass based on the solid content of the resist composition.

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

ここで、Ａｒ^c1は、芳香族炭化水素基を表す。
Ｒ^c5及びＲ^c6は、それぞれ独立に、水素原子、脂肪族炭化水素基（好ましくはアルキル基又はシクロアルキル基）、飽和環状炭化水素基又は芳香族炭化水素基を表す。但し該脂肪族炭化水素基、該飽和環状炭化水素基又は該芳香族炭化水素基に含まれる水素原子は、ヒドロキシ基、アミノ基、又は炭素数１〜６のアルコキシ基で置換されていてもよく、該アミノ基に含まれる水素原子は、炭素数１〜４のアルキル基で置換されていてもよい。
前記脂肪族炭化水素基は、好ましくは炭素数１〜６程度であり、前記飽和環状炭化水素基は、好ましくは炭素数５〜１０程度であり、前記芳香族炭化水素基は、好ましくは炭素数６〜１０程度である。
Ｒ^c7は、脂肪族炭化水素基（好ましくはアルキル基）、アルコキシ基、飽和環状炭化水素基（好ましくはシクロアルキル基）又は芳香族炭化水素基を表す。但し該脂肪族炭化水素基、該アルコキシ基、該飽和環状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、上記と同様の基で置換基されていてもよい。
ｍ３は０〜３の整数を表す。ｍ３が２以上のとき、複数のＲ^c7は、互いに同一でも異なってもよい。
Ｒ^c7の脂肪族炭化水素基、飽和環状炭化水素基及び芳香族炭化水素基の好ましい炭素数は、上記と同じであり、Ｒ^c7のアルコキシ基は、好ましくは炭素数１〜６程度である。

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

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

式（Ｃ３）〜式（Ｃ１１）中、
Ｒ^c8は、上記Ｒ^c7で説明したいずれかの基を表す。
窒素原子と結合するＲ^c9、Ｒ^c10、Ｒ^c11〜Ｒ^c14、Ｒ^c16〜Ｒ^c19及びＲ^c22は、それぞれ独立に、Ｒ^c5及びＲ^c6で説明したいずれかの基を表す。
芳香族炭素と結合するＲ^c20、Ｒ^c21、Ｒ^c23〜Ｒ^c28は、それぞれ独立に、Ｒ^c7で説明したいずれかの基を表す。
ｏ３、ｐ３、ｑ３、ｒ３、ｓ３、ｔ３及びｕ３は、それぞれ独立に０〜３の整数を表す。ｏ３〜ｕ３のいずれかが２以上であるとき、それぞれ、複数のＲ^c20〜Ｒ^c28のいずれかは互いに同一でも異なってもよい。
Ｒ^c15は、脂肪族炭化水素基、飽和環状炭化水素基又はアルカノイル基を表す。
ｎ３は０〜８の整数を表す。ｎ３が２以上のとき、複数のＲ^c15は、互いに同一でも異なってもよい。
Ｒ^c15の脂肪族炭化水素基は、好ましくは炭素数１〜６程度であり、飽和環状炭化水素基は、好ましくは炭素数３〜６程度であり、アルカノイル基は、好ましくは炭素数２〜６程度である。
Ｌ^c1及びＬ^c2は、それぞれ独立に、２価の脂肪族炭化水素基（好ましくはアルキレン基）、−ＣＯ−、−Ｃ（＝ＮＨ）−、−Ｃ（＝ＮＲ^c3）−、−Ｓ−、−Ｓ−Ｓ−又はこれらの組合せを表す。該２価の脂肪族炭化水素基は、好ましくは炭素数１〜６程度である。
Ｒ^c3は、炭素数１〜４のアルキル基を表す。 Examples of the basic compound (C) include compounds represented by the formulas (C3) to (C11).

In formula (C3) to formula (C11),
R ^c8 represents any of the groups described for R ^c7 above.
R ^c9 , R ^c10 , R ^{c11 to} R ^c14 , R ^{c16 to} R ^c19 and R ^c22 bonded to the nitrogen atom each independently represent any of the groups described for R ^c5 and R ^c6 .
R ^c20 , R ^c21 and R ^{c23 to} R ^c28 bonded to the aromatic carbon each independently represents any of the groups described for R ^c7 .
o3, p3, q3, r3, s3, t3 and u3 each independently represents an integer of 0 to 3. When any of o3 to u3 is 2 or more, any of the plurality of R ^{c20 to} R ^c28 may be the same as or different from each other.
R ^c15 represents an aliphatic hydrocarbon group, a saturated cyclic hydrocarbon group or an alkanoyl group.
n3 represents an integer of 0 to 8. When n3 is 2 or more, the plurality of R ^c15 may be the same as or different from each other.
The aliphatic hydrocarbon group represented by R ^c15 preferably has about 1 to 6 carbon atoms, the saturated cyclic hydrocarbon group preferably has about 3 to 6 carbon atoms, and the alkanoyl group preferably has 2 to 6 carbon atoms. Degree.
L ^c1 and L ^c2 are each independently a divalent aliphatic hydrocarbon group (preferably an alkylene group), —CO—, —C (═NH) —, —C (═NR ^c3 ) —, —S—. , -SS- or a combination thereof. The divalent aliphatic hydrocarbon group preferably has about 1 to 6 carbon atoms.
R ^c3 represents an alkyl group having 1 to 4 carbon atoms.

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

Examples of the compound (C4) include piperazine.
Examples of the compound (C5) include morpholine.
Examples of the compound (C6) include piperidine and hindered amine compounds having a piperidine skeleton described in JP-A No. 11-52575.
Examples of the compound (C7) include 2,2′-methylenebisaniline.
Examples of the compound (C8) include imidazole and 4-methylimidazole.
Examples of the compound (C9) include pyridine and 4-methylpyridine.
Examples of the compound (C10) include 1,2-di (2-pyridyl) ethane, 1,2-di (4-pyridyl) ethane, 1,2-di (2-pyridyl) ethene, and 1,2-di. (4-pyridyl) ethene, 1,3-di (4-pyridyl) propane, 1,2-di (4-pyridyloxy) ethane, di (2-pyridyl) ketone, 4,4′-dipyridyl sulfide, 4, 4'-dipyridyl disulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine and the like can be mentioned.
Examples of the compound (C11) include bipyridine.

［式（ＩＩ）中、Ｒ^４及びＲ^５は、それぞれ独立に、炭素数１〜１２の炭化水素基、炭素数１〜６のアルコキシ基、炭素数２〜７のアシル基、炭素数２〜７のアシルオキシ基、炭素数２〜７のアルコキシカルボニル基、ニトロ基又はハロゲン原子を表す。
ｃ及びｄは、それぞれ独立に、０〜４の整数を表し、ｃが２以上の場合、複数のＲ^４は互いに同一であるか相異なり、ｄが２以上の場合、複数のＲ^５は互いに同一であるか相異なる。］ <Compound represented by formula (II)>
The resist composition of the present invention preferably contains a compound represented by the formula (II).

[In Formula (II), R ⁴ and R ⁵ are each independently a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 7 carbon atoms, or 2 to 2 carbon atoms. 7 an acyloxy group, an alkoxycarbonyl group having 2 to 7 carbon atoms, a nitro group, or a halogen atom.
c and d each independently represent an integer of 0 to ^4. When c is 2 or more, the plurality of R ⁴ are the same or different from each other. When d is 2 or more, the plurality of R ⁵ are Identical or different. ]

Examples of the hydrocarbon group include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and combinations thereof.
Examples of the aliphatic hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, pentyl group, hexyl group, and nonyl group.
The alicyclic hydrocarbon group may be monocyclic or polycyclic, and may be either saturated or unsaturated. Examples thereof include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclononyl group, and cyclododecyl group, norbornyl group, adamantyl group, and the like. In particular, saturated cyclic hydrocarbon is preferable.
As aromatic hydrocarbon group, phenyl group, 1-naphthyl group, 2-naphthyl group, 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-propylphenyl group 4-isopropylphenyl group, 4-butylphenyl group, 4-t-butylphenyl group, 4-hexylphenyl group, 4-cyclohexylphenyl group, anthonyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group , Aryl groups such as mesityl group, biphenyl group, anthryl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl, and the like.
These combinations include alkyl-cycloalkyl groups, cycloalkyl-alkyl groups, aralkyl groups (eg, phenylmethyl group, 1-phenylethyl group, 2-phenylethyl group, 1-phenyl-1-propyl group, 1- Phenyl-2-propyl group, 2-phenyl-2-propyl group, 3-phenyl-1-propyl group, 4-phenyl-1-butyl group, 5-phenyl-1-pentyl group, 6-phenyl-1-hexyl Group) and the like.

Examples of the alkoxy group include a methoxy group and an ethoxy group.
Examples of the acyl group include an acetyl group, a propanoyl group, a benzoyl group, and a cyclohexylcarbonyl group.
Examples of the acyloxy group include a group in which an oxy group is bonded to the acyl group.
Examples of the alkoxycarbonyl group include a group in which a carbonyl group is bonded to the alkoxy group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

R ⁴ and R ⁵ in formula (II) are each independently an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an acyl having 2 to 4 carbon atoms. Group, an acyloxy group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 2 to 4 carbon atoms, a nitro group, or a halogen atom is preferable.
c and d are each independently preferably an integer of 0 to 2.

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

  When the compound represented by the formula (II) is included, the content thereof is preferably 0.05 to 10 parts by mass, and more preferably 0.5 to 3 parts by mass with respect to 100 parts by mass of the resin (A). It is preferable that the content of the compound represented by the formula (II) is in the above range because roughness such as line width roughness (LWR) and line edge roughness (LER) tends to be small.

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

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

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

<Method for producing resist pattern>
The method for producing a resist pattern of the present invention comprises:
(1) The process of apply | coating the resist composition of this invention mentioned above on a board | substrate,
(2) 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 (so-called pre-baking) or by using a decompression device to form a composition layer from which the solvent has been removed. The As for the temperature in this case, about 50-200 degreeC is illustrated, for example. The pressure is exemplified by about 1 to 1.0 × 10 ⁵ Pa.

The obtained composition layer is exposed using an exposure machine. The exposure machine may be an immersion exposure machine. At this time, exposure is usually performed through a mask corresponding to a required pattern. 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.) can be used such as those that convert the wavelength of the laser light from the above and radiate the harmonic laser light in the far ultraviolet region or the vacuum ultraviolet region. The exposure machine may irradiate an electron beam or extreme ultraviolet light (EUV) generated from plasma. In this specification, irradiating these radiations may be collectively referred to as “exposure”.

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

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

Next, an Example is given and this invention is demonstrated further more concretely. In the examples, “%” and “part” representing the content or amount used are based on weight unless otherwise specified. In the following example, the content ratio of each structural unit contained in the obtained resin is calculated from the obtained result and the charged amount of monomer by measuring the amount of unreacted monomer in the reaction mass using liquid chromatography. did. The weight average molecular weight Mw and the number average molecular weight Mn are values obtained by gel permeation chromatography. The measurement conditions are as follows.
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)
The compounds used in the resin synthesis are shown below.

Synthesis of Resin A1 A 4-necked flask equipped with a thermometer and a reflux tube was charged with 30.10 parts of 1,4-dioxane and bubbled with nitrogen gas for 30 minutes. After heating to 75 ° C. under a nitrogen seal, 23.00 parts of the compound represented by the above formula (A), 3.82 parts of the compound represented by the formula (B), a compound represented by the formula (C) 4.91 parts, 14.79 parts of compound represented by formula (D), 3.65 parts of compound represented by formula (E), 0.32 parts of azobisisobutyronitrile, azobis-2,4- A solution prepared by mixing 1.45 parts of dimethylvaleronitrile and 45.16 parts of 1,4-dioxane was added dropwise over 1 hour while maintaining 75 ° C. After completion of dropping, the mixture was kept at 75 ° C. for 5 hours. After cooling, the reaction solution was diluted with 55.19 parts of 1,4-dioxane. The diluted mass was poured into a mixed solution of 522 parts of methanol and 130 parts of ion exchange water with stirring, and the precipitated resin was collected by filtration. The residue was put into a liquid of 326 parts of methanol and filtered after stirring. The obtained filtrate was put into a liquid of 326 parts of methanol, and the operations of stirring and filtration were further performed twice. Thereafter, vacuum drying was performed to obtain 31 parts of resin. This resin is designated as A1.
Yield: 62%, weight average molecular weight Mw: 7600, molecular weight distribution (Mw / Mn): 1.72, content ratio (molar ratio) of each structural unit contained in the resin: (A) / (B) / ( C) / (D) / (E) = 33/10/13/30/14.

Synthesis of Resin A2 A 4-necked flask equipped with a thermometer and a reflux tube was charged with 38.72 parts of 1,4-dioxane and bubbled with nitrogen gas for 30 minutes. After heating up to 75 ° C. under a nitrogen seal, 20.00 parts of the compound represented by the above formula (F), 11.38 parts of the compound represented by the formula (B), a compound represented by the formula (G) 6.85 parts, compound represented by formula (E) 26.31 parts, azobisisobutyronitrile 0.53 parts, azobis-2,4-dimethylvaleronitrile 2.40 parts, 1,4-dioxane 58 0.09 part of the mixed solution was added dropwise over 1 hour while maintaining 73 ° C. After completion of dropping, the mixture was kept at 75 ° C. for 5 hours. After cooling, the reaction solution was diluted with 70.99 parts of 1,4-dioxane. The diluted mass was poured into a mixed solution of 671 parts of methanol and 168 parts of ion-exchanged water with stirring, and the precipitated resin was collected by filtration. The residue was put into a solution of 420 parts of methanol and filtered after stirring. The obtained filtrate was put into a solution of 420 parts of methanol, and the operations of stirring and filtration were further performed twice. Thereafter, vacuum drying was performed to obtain 56 parts of resin. This resin is designated as A2.
Yield: 86%, weight average molecular weight Mw: 8100, molecular weight distribution (Mw / Mn): 1.84, content ratio (molar ratio) of each structural unit contained in the resin: (F) / (B) / ( G) / (E) = 21/17/10/52.

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

<Resin>
A1: Resin A1
<Acid generator>
B1: Salt represented by the formula (B1-3)

<Compound represented by formula (I)>
Q1: Compound represented by formula (I-3)

Q2: Compound represented by formula (I-4)

＜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 １８０．０部
プロピレングリコールモノメチルエーテル ２０．０部
２−ヘプタノン １０．０部
γ−ブチロラクトン ３．０部 <Nitrogen-containing basic compound (quencher) (compound represented by formula (I))>
C1: 2,6-diisopropylaniline C2: compound represented by the formula (CA)

<Solvent>
Propylene glycol monomethyl ether acetate 180.0 parts Propylene glycol monomethyl ether 20.0 parts 2-heptanone 10.0 parts γ-butyrolactone 3.0 parts

An organic antireflective coating composition [ARC-29; manufactured by Nissan Chemical Co., Ltd.] was applied onto a 12-inch silicon wafer and baked at 205 ° C. for 60 seconds to obtain a thickness of 780 mm. An organic antireflection film was formed. Subsequently, the resist composition was spin-coated on the organic antireflection film so that the film thickness after drying (ie, pre-baking) was 120 nm.
After applying the resist composition, the obtained silicon wafer was pre-baked (PB) for 60 seconds on a direct hot plate at the temperature described in the “PB” column of Table 1. ArF excimer laser stepper for immersion exposure [XT: 1900 Gi; manufactured by ASML, NA = 1.20, 4-poles on axis illumination (σout = 0.97, σin = 0) .72, XY polarized light], the hole pattern was subjected to immersion exposure by changing the exposure amount stepwise, and ultrapure water was used as the immersion medium.
After the exposure, post exposure bake (PEB) is performed on the hot plate at a temperature described in the “PEB” column of Table 1 for 60 seconds, and further with a 2.38 mass% tetramethylammonium hydroxide aqueous solution for 60 seconds. Paddle development was performed to obtain a resist pattern.

  In pattern formation from each resist composition, an exposure dose at which the diameter of a hole pattern formed using a Pitch 500 nm Hole 160 nm mask becomes 140 nm was defined as effective sensitivity.

Depth of focus evaluation (DOF) (focus margin): The focus margin at the effective sensitivity at which the hole pattern is 140 nm was evaluated. When the focus is shaken, the diameter of the hole pattern is 135 nm ± 5 nm, and in the photograph taken from the upper surface, the focus (focus) range in which it was confirmed that the film has passed through to the bottom of the hole pattern is DOF. . A sample having a DOF of more than 135 nm was evaluated as ◯, and a sample having a DOF of 120 nm or less was evaluated as ×.
These results are shown in Table 2.

  The components shown in Table 3 below were mixed and dissolved, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

Ｂ３：式（Ｂ１−６）で表される塩

<Resin>
A2: Resin A2
<Acid generator>
B2: salt represented by formula (B1-2)

B3: salt represented by formula (B1-6)

<Compound represented by formula (I)>
Q1: Compound represented by formula (I-3) Q2: Compound represented by formula (I-4)

＜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 ２７０部
プロピレングリコールモノメチルエーテル ２５部
２−ヘプタノン ２０部
γ−ブチロラクトン ５部 <Compound represented by formula (II)>
C3: Compound represented by the formula (CD)

<Solvent>
Propylene glycol monomethyl ether acetate 270 parts Propylene glycol monomethyl ether 25 parts 2-heptanone 20 parts γ-butyrolactone 5 parts

An organic antireflective coating composition [ARC-29; manufactured by Nissan Chemical Co., Ltd.] was applied onto a 12-inch silicon wafer and baked at 205 ° C. for 60 seconds to obtain a thickness of 780 mm. An organic antireflection film was formed. Subsequently, the resist composition was spin-coated on the organic antireflection film so that the film thickness after pre-baking was 90 nm.
After applying the resist composition, the obtained silicon wafer was pre-baked (PB) for 60 seconds at a temperature described in the “PB” column of Table 3 on a direct hot plate. An ArF excimer laser stepper for immersion exposure [XT: 1900 Gi; manufactured by ASML, NA = 1.30, 4-poles on axis illumination (σout = 0.89, σin = 0) on the wafer thus formed with the resist composition film. .69, XY polarized light], the 1: 1 line pattern was subjected to immersion exposure by changing the exposure amount stepwise, and ultrapure water was used as the immersion medium.
After the exposure, post exposure bake (PEB) is performed on the hot plate at the temperature described in the “PEB” column of Table 3 for 60 seconds, and further with a 2.38 mass% tetramethylammonium hydroxide aqueous solution for 60 seconds. Paddle development was performed to obtain a resist pattern.

  In pattern formation from each resist composition, the exposure amount at which the line width of the 42 nm line-and-space pattern becomes 1: 1 was defined as the effective sensitivity.

  Line width roughness evaluation (LWR): The line width of the obtained resist pattern is observed with a scanning electron microscope, and the variation in the line width of the resist pattern (3σ; triple value of standard deviation σ) is less than 6.5 nm. The thing was made into (circle) and 6.5 nm or more was made into x. The results are shown in Table 4.

  Depth of focus evaluation (DOF): A resist pattern was obtained in the same manner as above except that the focus was changed stepwise to expose an exposure amount corresponding to the effective sensitivity. The line width roughness of the resist pattern was observed with a scanning electron microscope, and the focus range where the line width roughness was less than 8.0 nm was defined as DOF. The case where the DOF exceeds 160 nm is indicated by ◯, and the case where the DOF is 160 nm or less is indicated by ×. The results are shown in Table 4.

  The resist composition of the present invention has a wide focus margin when forming a resist pattern.

Claims (6)

A resin having an acid labile group and insoluble or hardly soluble in an aqueous alkali solution and soluble in an aqueous alkali solution by the action of an acid, an acid generator, and a compound represented by the formula (I): Containing a resist composition.

[In Formula (I), R ¹ , R ² and R ³ each independently represents an alkyl group having 1 to 6 carbon atoms.
s, t, and u each independently represent an integer of 0 to 3. When s is an integer of 2 or more, the plurality of R ¹ may be the same or different, and when t is an integer of 2 or more, the plurality of R ² may be the same or different. Well, when u is an integer of 2 or more, the plurality of R ³ may be the same or different, and when n is an integer of 2 or more, the plurality of t are the same or different. Also good.
n represents an integer of 1 to 3. ] The resist composition according to claim 1, wherein the acid generator is an acid generator represented by the formula (B1).

[In the formula (B1),
Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and —CH ₂ — contained in the divalent saturated hydrocarbon group is replaced by —O— or —CO—. May be.
Y represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent or a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, and the aliphatic group —CH ₂ — contained in the hydrocarbon group and the saturated cyclic hydrocarbon group may be replaced by —O—, —SO ₂ — or —CO—.
Z ⁺ represents an organic cation. ] The resist composition according to claim 2, wherein L ^b1 is * —CO—O— (* represents a bond with —C (Q ¹ ) (Q ² ) —). The resist composition according to claim 2 or 3, wherein Z ⁺ is an arylsulfonium cation.   Furthermore, the resist composition in any one of Claims 1-4 containing a nitrogen-containing basic compound. (1) The process of apply | coating the resist composition in any one of Claims 1-5 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 step of developing the heated composition layer using a developing device;
A method for producing a resist pattern including: