JP2012226345A - Resist composition and method for producing resist pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist composition showing a preferable focus margin in the process of producing a pattern and allowing production of a resist pattern with fewer defects.SOLUTION: The resist composition includes: (A1) a resin having a structural unit expressed by formula (I); (A2) a resin having a structural unit expressed by formula (II), which is insoluble or poorly soluble with an alkali aqueous solution and can dissolve in an alkali aqueous solution by the action of an acid; and (B) an acid generator. In the formulae, Rrepresents a hydrogen atom or a methyl group.

Description

  The present invention relates to a resist composition, a method for producing a resist pattern using the resist composition, and the like.

In Patent Document 1, a resin composed of a structural unit represented by the formula (u-A) and a structural unit represented by the formula (u-B), a structural unit represented by the formula (u-C), and a formula A resist composition containing a resin composed of a structural unit represented by (u-D) and a structural unit represented by formula (u-B), an acid generator, and a solvent is described.

JP 2010-197413 A

  Conventional resist compositions do not always satisfy the focus margin (DOF) at the time of producing a resist pattern, and there are cases where the number of defects is extremely large.

［式（Ｉ）中、
Ｒ^３は、水素原子又はメチル基を表す。
Ａ^１は、−（ＣＨ_２）_ｍ１−、−（ＣＨ_２）_ｍ２−Ｏ−（ＣＨ_２）_ｍ３−又は−（ＣＨ_２）_ｍ４−ＣＯ−Ｏ−（ＣＨ_２）_ｍ５−を表す。
ｍ１〜ｍ５は、それぞれ独立に、１〜６の整数を表す。
Ｒ²は、フッ素原子を有する炭素数１〜１０の炭化水素基を表す。］

［式（ＩＩ）中、
環Ｔ^１は、置換基を有していてもよい炭素数３〜３４のスルトン環を表す。
Ｚ^１は、置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は、−ＣＯ−、−Ｏ−又は−Ｎ（Ｒ^ｃ）−で置き換わっていてもよい。ただし、T^１−Ｏ−ＣＯ−における−ＣＯ−との結合位置となる−ＣＨ_２−は、−Ｎ（Ｒ^ｃ）で置き換わらない。
Ｒ^ｃは、水素原子又は炭素数１〜６のアルキル基を表す。
Ｒ^１は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。］
［２］Ｒ²が、炭素数１〜６のフッ化アルキル基である［１］記載のレジスト組成物。
［３］Ａ¹が、メチレン基である［１］又は［２］記載のレジスト組成物。
［４］環Ｔ^１が、多環式のスルトン環である［１］〜［３］のいずれか記載のレジスト組成物。
［５］環Ｔ^１が、式（Ｔ１）で表される環である［１］〜［４］のいずれか記載のレジスト組成物。

［式（Ｔ１）中、
Ｒ^４は、ハロゲン原子又はヒドロキシ基を有していてもよい炭素数１〜１２のアルキル基、ハロゲン原子、ヒドロキシ基、オキシ基、シアノ基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基、炭素数２〜１２のアルコキシカルボニル基あるいは炭素数２〜４のアシル基を表す。
ｍは、０〜９の整数を表す。ｍが２以上のとき、複数のＲ⁴は同一又は相異なる。
＊は、酸素原子との結合手を表す。］
［６］Ｚ^１が、−ＮＨ−（ＣＨ_２）_ｎ１−＊又は−ＮＨ−（ＣＨ_２）_ｎ１−ＣＯＯ−（ＣＨ_２）_ｎ２−＊（ｎ１及びｎ２は、それぞれ独立に、１〜６の整数を表し、＊はT^１−Ｏ−ＣＯ−の結合手を表す。）である［１］〜［５］のいずれか記載のレジスト組成物。
［７］さらに溶剤を含有する上記［１］〜［６］のいずれか記載のレジスト組成物。
［８］（１）上記［１］〜［７］のいずれか記載のレジスト組成物を基板上に塗布する工程、
（２）塗布後の組成物を乾燥させて組成物層を形成する工程、
（３）組成物層を露光する工程、
（４）露光後の組成物層を加熱する工程及び
（５）加熱後の組成物層を現像する工程を含むレジストパターンの製造方法。 The present invention includes the following inventions.
[1] (A1) a resin having a structural unit represented by formula (I),
(A2) Resin composition having a structural unit represented by formula (II), insoluble or hardly soluble in an alkaline aqueous solution, and soluble in an alkaline aqueous solution by the action of an acid, and (B) an acid generator object.

[In the formula (I),
R ³ represents a hydrogen atom or a methyl group.
A ¹ _{is, - (CH 2) m1 -} , - (CH 2) m2 -O- (CH 2) m3 - or _{- (CH 2) m4 -CO-} O- (CH 2) m5 - represents a.
m1 to m5 each independently represents an integer of 1 to 6.
R ² represents a C 1-10 hydrocarbon group having a fluorine atom. ]

[In the formula (II),
Ring T ¹ represents a C3-C34 sultone ring which may have a substituent.
Z ¹ represents a C 1-17 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —CO—, —O— or —N. (R ^c )-may be substituted. However, —CH ₂ — which is a bonding position to —CO— in T ¹ —O—CO— is not replaced by —N (R ^c ).
R ^c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
R ¹ represents a C 1-6 alkyl group, a hydrogen atom or a halogen atom which may have a halogen atom. ]
[2] The resist composition according to [1], wherein R ² is a fluorinated alkyl group having 1 to 6 carbon atoms.
[3] The resist composition according to [1] or [2], wherein A ¹ is a methylene group.
[4] The resist composition according to any one of [1] to [3], wherein the ring T ¹ is a polycyclic sultone ring.
[5] ring ^{T 1} is a ring represented by the formula (T1) [1] ~ resist composition according to any one of [4].

[In the formula (T1),
R ⁴ is a C 1-12 alkyl group optionally having a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, an oxy group, a cyano group, a C 1-12 alkoxy group, a C 6-12 12 represents an aryl group having 12 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an acyl group having 2 to 4 carbon atoms.
m represents an integer of 0 to 9. When m is 2 or more, the plurality of R ⁴ are the same or different.
* Represents a bond with an oxygen atom. ]
[6] Z ¹ is —NH— (CH ₂ ) _n1 — * or —NH— (CH ₂ ) _n1 —COO— (CH ₂ ) _n2 — * (n1 and n2 are each independently 1 to 6 An integer, and * represents a bond of T ¹ —O—CO—.) The resist composition according to any one of [1] to [5].
[7] The resist composition according to any one of [1] to [6], further containing a solvent.
[8] (1) A step of applying the resist composition according to any one of [1] to [7] on a substrate,
(2) The process of drying the composition after application | coating and forming a composition layer,
(3) a step of exposing the composition layer,
(4) A method for producing a resist pattern, comprising: a step of heating the composition layer after exposure; and (5) a step of developing the composition layer after heating.

  According to the resist composition of the present invention, it is possible to obtain a resist pattern having a good focus margin (DOF) at the time of producing the resist pattern and few defects.

In this specification, "(meth) acrylic monomer" means at least one monomer having the structure of "CH ₂ = CH-CO-" or _{"CH 2 = C (CH 3)} -CO- " 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.

<Resist composition>
The resist composition of the present invention comprises:
It contains (A) a resin (hereinafter sometimes referred to as “resin (A)”) and (B) an acid generator (hereinafter sometimes referred to as “acid generator (B)”).
Here, the resin (A) includes the following resins.
(A1) a resin having a structural unit represented by formula (I) (hereinafter sometimes referred to as “resin (A1)”),
(A2) A resin having a structural unit represented by the formula (II), insoluble or hardly soluble in an alkaline aqueous solution, and soluble in an alkaline aqueous solution by the action of an acid (hereinafter referred to as “resin (A2)”) ).
The resist composition of the present invention preferably further contains a solvent (E) (hereinafter sometimes referred to as “solvent (E)”).
The resist composition of the present invention preferably further contains a basic compound.

<Resin (A)>
The resin (A) contained in the resist composition of the present invention includes the resins (A1) and (A2) described above, and includes resins other than the resins (A1) and (A2) as described later. May be.

［式（Ｉ）中、
Ｒ^３は、水素原子又はメチル基を表す。
Ａ^１は、−（ＣＨ_２）_ｍ１−、−（ＣＨ_２）_ｍ２−Ｏ−（ＣＨ_２）_ｍ３−又は−（ＣＨ_２）_ｍ４−ＣＯ−Ｏ−（ＣＨ_２）_ｍ５−を表す。
ｍ１〜ｍ５は、それぞれ独立に、１〜６の整数を表す。
Ｒ²は、フッ素原子を有する炭素数１〜１０の炭化水素基を表す。］ <Resin (A1)>
The resin (A1) has a structural unit represented by the formula (I) (hereinafter sometimes referred to as “structural unit (I)”).

[In the formula (I),
R ³ represents a hydrogen atom or a methyl group.
A ¹ _{is, - (CH 2) m1 -} , - (CH 2) m2 -O- (CH 2) m3 - or _{- (CH 2) m4 -CO-} O- (CH 2) m5 - represents a.
m1 to m5 each independently represents an integer of 1 to 6.
R ² represents a C 1-10 hydrocarbon group having a fluorine atom. ]

A ^{1 in} formula (I) is preferably — (CH ₂ ) _m1 —, more preferably an ethylene group or a methylene group, and still more preferably a methylene group.

The hydrocarbon group for R ² includes an aliphatic hydrocarbon group and an aromatic hydrocarbon group, and the aliphatic hydrocarbon group includes a chain type, a cyclic type, and a combination thereof. As the aliphatic hydrocarbon group, an alkyl group and an alicyclic hydrocarbon group are preferable.
Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. .
The alicyclic hydrocarbon group may be monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a methyl group. Examples thereof include cycloalkyl groups such as cyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1- (adamantan-1-yl) alkane-1-yl group, and norbornyl. Group, methylnorbornyl group and isobornyl group.

Examples of the hydrocarbon group having a fluorine atom include an alkyl group having a fluorine atom and an alicyclic hydrocarbon group having a fluorine atom.
Examples of the alkyl group having a fluorine atom include difluoromethyl group, trifluoromethyl group, 1,1,1-trifluoroethyl group, perfluoroethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2 , 2,2-trifluoroethyl group, 1,1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, 1,1,1,2,2- Pentafluoropropyl group, perfluoropropyl group, 1,1,1,2,2,3,3-peptafluorobutyl group, perfluorobutyl group, 1,1,1,2,2,3,3,4,4 -Fluoroalkyl groups such as nonafluoropentyl group, perfluoropentyl group, perfluorohexyl group, perfluoroheptyl group and perfluorooctyl group.
Examples of the alicyclic hydrocarbon group having a fluorine atom include fluorinated cycloalkyl groups such as a perfluorocyclohexyl group and a perfluoroadamantyl group.
R ² is preferably a fluorinated alkyl group, more preferably a fluorinated alkyl group having 1 to 6 carbon atoms.

Examples of the structural unit (I) include the following.

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

［式（Ｉ’）中、Ｒ^３、Ａ^１及びＲ²は、上記と同じ意味を表す。］ The structural unit (I) is derived from a compound represented by the formula (I ′) (hereinafter sometimes referred to as “compound (I ′)”).

[In Formula (I ′), R ³ , A ¹ and R ² represent the same meaning as described above. ]

［式中、Ｒ^３、Ａ^１及びＲ²は、上記と同じ意味を表す。］
式（Ｉ’−１）で表される化合物と式（Ｉ’−２）で表される化合物とを、溶媒中、触媒の存在下で反応させることが好ましい。溶媒としては、ジメチルホルムアミドなどが用いられる。触媒としては、炭酸カリウム及びヨウ化カリウムなどを用いられる。 Compound (I ′) can be produced, for example, by the following reaction.

[Wherein R ³ , A ¹ and R ² represent the same meaning as described above. ]
It is preferable to react the compound represented by the formula (I′-1) and the compound represented by the formula (I′-2) in a solvent in the presence of a catalyst. As the solvent, dimethylformamide or the like is used. As the catalyst, potassium carbonate and potassium iodide are used.

式（Ｉ’−３）で表される化合物は、Ａ¹の種類に応じて適当なものを用いることができる。
Ａ¹がメチレン基である場合の式（Ｉ’−２）で表される化合物は、式（Ｉ’−３）で表される化合物として、例えば、クロロアセチルクロリドなどを用いることにより製造することができる。このクロロアセチルクロリドは市場から容易に入手できる。
式（Ｉ’−４）で表される化合物は、Ｒ²の種類に応じて適当なアルコールを用いることができる。
Ｒ²がフッ素原子で置換された脂肪族炭化水素基である式（Ｉ’−２）で表される化合物は、式（Ｉ’−４）で表される化合物として、例えば、２，２，３，３，４，４，４−ヘプタフルオロ−１−ブタノールなどを用いることにより製造することができる。この２，２，３，３，４，４，４−ヘプタフルオロ−１−ブタノールは市場から容易に入手できる。 The compound represented by the formula (I′-1) is preferably a compound (commercially available) that can be easily obtained from the market. Such commercial products include methacrylic acid.
The compound represented by the formula (I′-2) is produced, for example, by reacting the compound represented by the formula (I′-3) with the compound represented by the formula (I′-4). Can do. This reaction is carried out in a solvent in the presence of a base catalyst. The solvent used in this reaction is tetrahydrofuran or the like. As the base catalyst, pyridine or the like is used.

As the compound represented by the formula (I′-3), an appropriate compound can be used depending on the type of A ¹ .
The compound represented by the formula (I′-2) when A ¹ is a methylene group is produced by using, for example, chloroacetyl chloride as the compound represented by the formula (I′-3). Can do. This chloroacetyl chloride is readily available from the market.
As the compound represented by the formula (I′-4), an appropriate alcohol can be used depending on the type of R ² .
The compound represented by the formula (I′-2), in which R ² is an aliphatic hydrocarbon group substituted with a fluorine atom, includes, for example, 2, 2, as the compound represented by the formula (I′-4) It can be produced by using 3,3,4,4,4-heptafluoro-1-butanol or the like. This 2,2,3,3,4,4,4-heptafluoro-1-butanol is readily available from the market.

［式（ＩＩＩＡ）中、
Ｒ^１１は、水素原子又はメチル基を表す。
環Ｗ^２は、炭素数６〜１０の炭化水素環を表す。
Ａ^１２は、−Ｏ−、^＊−ＣＯ−Ｏ−又は^＊−Ｏ−ＣＯ−（^＊は環Ｗ^１との結合手を表す。）を表す。
Ｒ^１２は、フッ素原子を有する炭素数１〜６のアルキル基を表す。］ The resin (A1) may have a structural unit different from the structural unit (I).
The structural unit different from the structural unit (I) includes a structural unit derived from the acid labile monomer (a1) described later, a structural unit derived from the acid stable monomer (a4), and a structural unit represented by the formula (IIIA) And structural units derived from known monomers used in the art. A structural unit represented by the formula (IIIA) is preferable.

[In the formula (IIIA),
R ¹¹ represents a hydrogen atom or a methyl group.
Ring ^{W 2} represents a hydrocarbon ring having 6 to 10 carbon atoms.
A ¹² represents —O—, ^* —CO—O—, or ^* —O—CO— ( ^* represents a bond to ring W ¹ ).
R ¹² represents a C 1-6 alkyl group having a fluorine atom. ]

Examples of the hydrocarbon ring of ring W ² include an alicyclic hydrocarbon ring, and a saturated alicyclic hydrocarbon ring is preferable.
Examples of the saturated alicyclic hydrocarbon ring include the following rings.

Ring W ² is preferably an adamantane ring or a cyclohexane ring, and more preferably an adamantane ring.
The alkyl group having 1 to 6 carbon atoms and having a fluorine atom in R ^12, for example, the following groups.

上記の構造単位において、Ｒ^１１に相当するメチル基が水素原子に置き換わった構造単位も、構造単位（ＩＩＩＡ）の具体例として挙げることができる。
中でも、式（ＩＩＩＡ−１）で表される構造単位又はＲ^１１に相当するメチル基が水素原子に置き換わった構造単位が特に好ましい。 As the structural unit represented by the formula (IIIA), structural units represented by the following are preferable.

In the structural unit, a structural unit in which a methyl group corresponding to R ¹¹ is replaced with a hydrogen atom can also be given as a specific example of the structural unit (IIIA).
Among these, a structural unit represented by the formula (IIIA-1) or a structural unit in which a methyl group corresponding to R ¹¹ is replaced with a hydrogen atom is particularly preferable.

The content ratio of the structural unit (I) in the resin (A1) is more preferably in the range of 5 to 100 mol%, further preferably in the range of 10 to 100 mol%, based on all the structural units of the resin (A1). The range of 50 to 100 mol% is more preferable, and the range of 80 to 100 mol% is particularly preferable.
When the resin (A1) has the structural unit (IIIA), the content ratio of the structural unit (IIIA) in the resin (A1) is in the range of 1 to 95 mol% with respect to all the structural units of the resin (A1). The range of 2 to 80 mol% is more preferable, the range of 5 to 70 mol% is more preferable, the range of 5 to 50 mol% is particularly preferable, and the range of 5 to 30 mol% is particularly preferable. When the structural unit (IIIA) is included and the content ratio is within the above range, a resist pattern having an excellent focus margin (DOF) and few defects can be manufactured.
Resin (A1) having structural units (I) and / or (IIIA) in such a content ratio is compound (I ′), structural unit (IIIA) relative to the total molar amount of all monomers used in the production of resin (A1). It can be produced by adjusting the molar amount of the monomer used for deriving.

  Each structural unit (I) and / or (IIIA) constituting the resin (A1) may be one kind or a combination of two or more kinds, and optionally, an acid stable monomer (a1), an acid stable monomer, which will be described later, It can be produced by a known polymerization method (for example, radical polymerization method) by combining one or more monomers known in the art.

The weight average molecular weight of the resin (A1) is preferably 5,000 or more (more preferably 7,000 or more, more preferably 10,000 or more), 80,000 or less (more preferably 50,000 or less, further preferably Is 30,000 or less). A weight average molecular weight is calculated | required as a conversion value of a standard polystyrene reference | standard by gel permeation chromatography analysis, and the detailed analysis conditions of this analysis are explained in full detail in the Example of this application.

<Resin (A2)>
The resin (A2) has a structural unit represented by the formula (II) (hereinafter sometimes referred to as “structural unit (II)”), is insoluble or hardly soluble in an alkaline aqueous solution, and is alkaline aqueous solution by the action of an acid. Can be dissolved. Here, “can be dissolved in an alkaline aqueous solution by the action of an acid” means that the resin (A2) has an acid-labile group (hereinafter sometimes referred to as “acid-labile group”), It is insoluble or hardly soluble in the aqueous alkali solution before contact with the water, but it becomes soluble in the aqueous alkali solution after contact with the acid.
The resin (A2) further has a structural unit different from the structural unit (II), and this different structural unit has an acid labile group. That is, the resin (A2) has a structural unit derived from a monomer having an acid labile group (hereinafter sometimes referred to as “acid labile monomer (a1)”) in addition to the structural unit (II).
The resin (A2) is a structural unit derived from a monomer having no acid labile group (hereinafter sometimes referred to as “acid-stable monomer”), a monomer known in the art, The structural unit (I) and the structural unit represented by the formula (IIIA) may be included.
The resin (A2) may be a different resin different from the resin (A1), or has a structural unit represented by the formula (I) and a structural unit represented by the formula (II), and an alkali. A resin that is insoluble or hardly soluble in an aqueous solution and can be dissolved in an alkaline aqueous solution by the action of an acid may be used.

［式（ＩＩ）中、
環Ｔ^１は、置換基を有していてもよい炭素数３〜３４のスルトン環を表す。
Ｚ^１は、置換基を有していてもよい炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基に含まれる−ＣＨ_２−は、−ＣＯ−、−Ｏ−又は−Ｎ（Ｒ^ｃ）−で置き換わっていてもよい。ただし、T^１−Ｏ−ＣＯ−における−ＣＯ−との結合位置となる−ＣＨ_２−は、−Ｎ（Ｒ^ｃ）で置き換わらない。
Ｒ^ｃは、水素原子又は炭素数１〜６のアルキル基を表す。
Ｒ^１は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。］

[In the formula (II),
Ring T ¹ represents a C3-C34 sultone ring which may have a substituent.
Z ¹ represents a C 1-17 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —CO—, —O— or —N. (R ^c )-may be substituted. However, —CH ₂ — which is a bonding position to —CO— in T ¹ —O—CO— is not replaced by —N (R ^c ).
R ^c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
R ¹ represents a C 1-6 alkyl group, a hydrogen atom or a halogen atom which may have a halogen atom. ]

スルトン環が有していてもよい置換基としては、ハロゲン原子又はヒドロキシ基を有していてもよい炭素数１〜１２のアルキル基、ハロゲン原子、ヒドロキシ基、シアノ基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基、炭素数２〜１２のアルコキシカルボニル基あるいは炭素数２〜４のアシル基等が挙げられる。 Sultone ring of ^{T 1} in the ring ^{T 1} of the formula (II), as an atomic group forming a ring, means a ring containing _-SO 2 -O-.
As the sultone ring, for example, a compound represented by any one of the following formula (T ¹ -1), formula (T ¹ -2), formula (T ¹ -3) and formula (T ¹ -4) is constituted. In this structure, one of the hydrogen atoms to be replaced is replaced with a bond. The sultone ring may be monocyclic but is preferably polycyclic. The polycyclic sultone ring refers to a bridged ring containing _-SO 2 -O- as atomic group forming a ring, for example, represented by the formula ^(T 1 -1) or formula ^(T 1 -2) Ring. Incidentally, sultone ring, as the ring represented by the formula (T 1 ^-2), as an atomic group forming a ring, other than -SO 2 _-O-, may contain a further hetero atom. Examples of the hetero atom include an oxygen atom, a sulfur atom, and a nitrogen atom. Among them, an oxygen atom is preferable.

Examples of the substituent that the sultone ring may have include an alkyl group having 1 to 12 carbon atoms that may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, and 1 to 12 carbon atoms. Examples thereof include an alkoxy group, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, and an acyl group having 2 to 4 carbon atoms.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group.
Examples of the alkyl group having a halogen atom include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluorosec-butyl group, perfluorotert-butyl group, perfluoropentyl group, perfluorohexyl group, A trichloromethyl group, a tribromomethyl group, a triiodomethyl group, etc. are mentioned.
Examples of the alkyl group having a hydroxy group include a hydroxymethyl group and a 2-hydroxyethyl group.
Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy group.
Aryl groups include phenyl, naphthyl, anthryl, p-methylphenyl, p-tert-butylphenyl, p-adamantylphenyl, tolyl, xylyl, cumenyl, mesityl, biphenyl, phenanthryl. Group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl and the like.
Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group.
Examples of the alkoxycarbonyl group include groups in which a carbonyl group is further bonded to an alkoxy group such as a methoxycarbonyl group or an ethoxycarbonyl group.
Examples of the acyl group include an acetyl group, a propionyl group, and a butyryl group.

The alkyl group in the substituent of ring represented by the formula ^(T 1 -1) ~ formula ^(T 1 -4), preferably an alkyl group having 1 to 6 carbon atoms, preferably a methyl group.
The alkyl group having a halogen atom or a hydroxy group is preferably a hydroxymethyl group, a hydroxyethyl group, a trifluoromethyl group, or the like.
The alkoxycarbonyl group preferably has 6 or less carbon atoms, and more preferably a methoxycarbonyl group.
In addition, as a sultone ring, the sultone ring which does not have a substituent is preferable from a viewpoint that manufacture of the compound which can derive | lead-out structural unit (II) is easy.

［式（Ｔ１’）中、
Ｘ¹¹、Ｘ¹²及びＸ¹³は、それぞれ独立に、酸素原子、硫黄原子又はメチレン基を表す。
Ｒ⁴¹は、ハロゲン原子又はヒドロキシ基を有していてもよい炭素数１〜１２のアルキル基、ハロゲン原子、ヒドロキシ基、オキシ基、シアノ基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシジルオキシ基、炭素数２〜１２のアルコキシカルボニル基あるいは炭素数２〜４のアシル基を表す。
ｍａは、０〜９の整数を表す。ｍａが２以上のとき、複数のＲ⁴¹は同一又は相異なる。
＊は、酸素原子との結合手を表す。］ The ring T ¹ is preferably a ring represented by the following formula (T1 ′).

[In the formula (T1 ′),
X ¹¹ , X ¹² and X ¹³ each independently represent an oxygen atom, a sulfur atom or a methylene group.
R ⁴¹ is a halogen atom or an alkyl group having 1 to 12 carbon atoms which may have a hydroxy group, a halogen atom, hydroxy group, aryloxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, 6 carbon atoms 12 represents an aryl group having 12 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an acyl group having 2 to 4 carbon atoms.
ma represents an integer of 0 to 9. When ma is 2 or more, the plurality of R ⁴¹ are the same or different.
* Represents a bond with an oxygen atom. ]

X ¹¹ , X ¹² and X ¹³ are each independently preferably an oxygen atom or a methylene group. When one of X ¹¹ , X ¹² and X ¹³ is an oxygen atom, the remaining two are methylene groups. Are preferred. In the case where one is an oxygen atom, X ¹¹ is preferably an oxygen atom.
R ⁴¹ is preferably a C 1-12 alkyl group which may have a halogen atom or a hydroxy group.

［式（Ｔ１）中、
Ｒ^４は、ハロゲン原子又はヒドロキシ基を有していてもよい炭素数１〜１２のアルキル基、ハロゲン原子、ヒドロキシ基、オキシ基、シアノ基、炭素数１〜１２のアルコキシ基、炭素数６〜１２のアリール基、炭素数７〜１２のアラルキル基、グリシドジルオキシ基、炭素数２〜１２のアルコキシカルボニル基あるいは炭素数２〜４のアシル基を表す。
ｍは、０〜９の整数を表す。ｍが２以上のとき、複数のＲ⁴は同一又は相異なる。
＊は、酸素原子との結合手を表す。］
式（Ｔ１’）におけるｍａ及び式（Ｔ１）におけるｍは、好ましくは０又は１であり、より好ましくは０である。 Further, the ring T ¹ is more preferably a ring represented by the formula (T1).

[In the formula (T1),
R ⁴ is a C 1-12 alkyl group optionally having a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, an oxy group, a cyano group, a C 1-12 alkoxy group, a C 6-12 It represents a 12 aryl group, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an acyl group having 2 to 4 carbon atoms.
m represents an integer of 0 to 9. When m is 2 or more, the plurality of R ⁴ are the same or different.
* Represents a bond with an oxygen atom. ]
Ma in the formula (T1 ′) and m in the formula (T1) are preferably 0 or 1, and more preferably 0.

Examples of the ring represented by the formula (T1 ′) and the ring represented by the formula (T1) include the following rings.

The saturated hydrocarbon group for Z ¹ may be an alkanediyl group, a divalent alicyclic hydrocarbon group, or a group obtained by combining these. Of these, an alkanediyl group is preferable, and a linear alkanediyl group is more preferable.
—CH ₂ — contained in the saturated hydrocarbon group may be replaced by one or more of —CO—, —O—, and —N (R ^c ) —. However, —CH ₂ — which is a bonding position to —CO— in T ¹ —O—CO— is not replaced by —N (R ^c ). That is, a nitrogen atom is not bonded to a carbon atom of —CO— in T ¹ —O—CO—.
Examples of this replaced group include:
_{^{-N (R c) - (CH}} 2) u1 - *,
_{^{-N (R c) - (CH}} 2) u1 -O- *,
_{^{-N (R c) - (CH}} 2) u1 -O- (CH 2) u2 - *,
_{^{-N (R c) - (CH}} 2) u1 -COO- (CH 2) u2 - *,
(However, R ^c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, u1 and u2 each independently represent an integer of 1 to 6, and * represents a bond of T ¹ —O—CO—. Represents).
Among these, preferably, Z ¹ includes —NH—, for example, —NH— (CH ₂ ) _u1 — * or —NH— (CH ₂ ) _u1 —COO— (CH ₂ ) _n2 — *. And more preferably —NH— (CH ₂ ) _{u1 ′} — * or —NH— (CH ₂ ) _{u1 ′} —COO— (CH ₂ ) _{u2 ′} — * (where u1 ′ and u2 ′ are each Independently represents 1 or 2.

Examples of the substituent of the saturated hydrocarbon group of Z ^1, an alkyl group having 1 to 6 carbon atoms and an alkoxy group having 1 to 6 carbon atoms.

Examples of the halogen atom for R ¹ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
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. And alkyl groups such as a group, octyl group, nonyl group, decyl group, undecyl group, and dodecyl group.
Examples of the alkyl group having a halogen atom include trifluoromethyl group, 1,1,1-trifluoroethyl group, perfluoroethyl group, 1,1,1,2,2-pentafluoropropyl group, perfluoropropyl group, 1, 1,1,2,2,3,3-peptafluorobutyl group, perfluorobutyl group, 1,1,1,2,2,3,3,4,4-nonafluoropentyl group, perfluoropentyl group, perfluoro Examples include fluorinated alkyl groups such as hexyl group, perfluoroheptyl group, and perfluorooctyl group.
Among these, R ¹ is preferably an alkyl group having no halogen atom or a hydrogen atom, and more preferably a hydrogen atom or a methyl group.

Examples of the structural unit (II) include the following compounds.

上記の構造単位の具体例において、Ｒ^１に相当するメチル基が水素原子に置き換わった構造単位も、構造単位（ＩＩ）の具体例として挙げることができる。

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

［式（ＩＩ’）中の符号はいずれも、前記と同義である。］ The structural unit (II) is derived from a compound represented by the following formula (II ′) (compound (II ′)).

[All the symbols in formula (II ′) have the same meanings as described above. ]

［式中の符号はいずれも、前記と同義である。］ Compound (II ′) can be produced by the following production method or a production method analogous thereto.
For example, the compound (aa′1) in which Z ¹ is —NH—CH ₂ — * (* is a bond to T ¹ —O—CO—) is a compound represented by the formula (aa1-a); It can manufacture by making the compound represented by a formula (aa1-b) react in presence of a solvent. Examples of the solvent include tetrahydrofuran and acetonitrile.

[All symbols in the formula are as defined above. ]

As the compound (aa1-a), in the compound represented by any one of the above formulas (T ¹ -1) to (T ¹ -4), one of the hydrogen atoms constituting the compound is substituted with a hydroxy group And the like. When the compound (aa1-a) is thus selected, compounds (aa1 ′) having various sultone rings can be produced. As typical examples of the compound (aa1-a), those readily available from the market are exemplified.

Compound (aa1-b) can be obtained by reacting a compound represented by formula (aa1-c) with a compound represented by formula (aa1-d) in the presence of a solvent. Examples of the solvent include methylene chloride.

As typical examples of the compound (aa1-c), those readily available from the market are exemplified.

  The content ratio of the structural unit (II) is usually in the range of 2 to 40 mol%, preferably in the range of 3 to 35 mol%, preferably 5 to 30 with respect to all the structural units (100 mol%) of the resin (A2). A range of mol% is more preferable. Resin (A2) having structural unit (II) in such a content ratio is produced by adjusting the amount of compound (II ′) used relative to the total amount of all monomers used in the production of resin (A2). Can do.

<Acid labile monomer (a1)>
The “acid labile group” means a group that has a leaving group, and the leaving group is removed by 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 a group represented by the formula (1) and a group represented by the formula (2).

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

［式（２）中、Ｒ^ａ１’及びＲ^ａ２’は、それぞれ独立に、水素原子又は炭素数１〜１２の炭化水素基を表し、Ｒ^ａ３’は、炭素数１〜２０の炭化水素基を表すか、Ｒ^ａ２’及びＲ^ａ３’は互いに結合して炭素数２〜２０の２価の炭化水素基を形成し、前記炭化水素基及び前記２価の炭化水素基に含まれる−ＣＨ_２−は、−Ｏ―又は―Ｓ−で置き換わってもよい。］

In Expression (1), R ^a1 ~R ^a3 each independently represent a cycloaliphatic hydrocarbon radical of the alkyl group or 3 to 20 carbon atoms having 1 to 8 carbon atoms, R ^a1 and R ^a2 are each Bonding to form a divalent hydrocarbon group having 2 to 20 carbon atoms. * Represents a bond. ]

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

式（１）においては、Ｒ^a1〜Ｒ^a3の脂環式炭化水素基は、好ましくは炭素数３〜１６である。 ^Examples of the alkyl group represented by R ^{a1 to} R ^a3 include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.
The alicyclic hydrocarbon group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, and dimethylcyclohexane. Examples thereof include a cycloalkyl group such as a hexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, a methylnorbornyl group, and the following groups.

In Formula (1), the alicyclic hydrocarbon group of R ^{a1 to} R ^a3 preferably has 3 to 16 carbon atoms.

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

Examples of the group represented by the formula (1) include a 1,1-dialkylalkoxycarbonyl group (in the formula (1), R ^{a1 to} R ^a3 are alkyl groups, preferably a tert-butoxycarbonyl group), 2-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).

Examples of the hydrocarbon group for R ^{a1 ′ to} R ^{a3 ′} include an alkyl group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group.
Examples of the alkyl group and alicyclic hydrocarbon group are the same as those described above.
Aromatic hydrocarbon groups include phenyl, naphthyl, anthryl, p-methylphenyl, p-tert-butylphenyl, p-adamantylphenyl, tolyl, xylyl, cumenyl, mesityl, biphenyl Groups, phenanthryl groups, 2,6-diethylphenyl groups, aryl groups such as 2-methyl-6-ethylphenyl, and the like.
In the formula (2), it is preferable that at least one of R ^{a1 ′} and R ^{a2 ′} is a hydrogen atom.
Specific examples of the group represented by the formula (2) include the following groups.

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

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

  The (meth) acrylic monomer having an acid labile group and an alicyclic hydrocarbon group is preferably a monomer for deriving a structural unit represented by formula (a1-1) or represented by formula (a1-2). And a monomer that induces a structural unit. These may be used alone or in combination of two or more. In this specification, the structural unit represented by the formula (a1-1) and the structural unit represented by the formula (a1-2) are represented by the structural unit (a1-1) and the structural unit (a1-2), respectively. The monomer that derives the structural unit (a1-1) and the monomer that derives the structural unit (a1-2) may be referred to as a monomer (a1-1) and a monomer (a1-2), respectively.

［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−を表し、ｋ１は１〜７の整数を表し、＊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のアルキル基又は炭素数３〜１０の脂環式炭化水素基を表す。
ｍ１は０〜１４の整数を表す。
ｎ１は０〜１０の整数を表す。
ｎ１’は０〜３の整数を表す。］

[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, and * represents a bond to —CO—. Represents a hand.
R ^a4 and R ^a5 each independently represent a hydrogen atom or a methyl group.
R ^a6 and R ^a7 each independently represent an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 10 carbon atoms.
m1 represents the integer of 0-14.
n1 represents an integer of 0 to 10.
n1 ′ represents an integer of 0 to 3. ]

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。
ｎ１’は好ましくは０又は１である。 L ^a1 and L ^a2 are preferably —O— or ^* —O— (CH ₂ ) _k1 —CO—O—, more preferably —O—. k1 is preferably an integer of 1 to 4, more preferably 1.
R ^a4 and R ^a5 are preferably methyl groups.
^Examples of the alkyl group for R ^a6 and R ^a7 include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. The alkyl group for R ^a6 and R ^a7 preferably has 6 or less carbon atoms.
The alicyclic hydrocarbon group for R ^a6 and R ^a7 may be monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, Examples thereof include cycloalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, and cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, a 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.
n1 ′ is preferably 0 or 1.

As a monomer (a1-1), the monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned, for example. Monomers represented by the following formulas (a1-1-1) to (a1-1-8) are preferred, and monomers represented by the following formulas (a1-1-1) to (a1-1-4) are more preferred. .

Examples of the monomer (a1-2) include 1-ethylcyclopentan-1-yl (meth) acrylate, 1-ethylcyclohexane-1-yl (meth) acrylate, and 1-ethylcycloheptan-1-yl (meth). Examples include acrylate, 1-methylcyclopentan-1-yl (meth) acrylate, and 1-isopropylcyclopentan-1-yl (meth) acrylate. Monomers represented by the following formulas (a1-2-1) to (a1-2-12) are preferred, and the following formulas (a1-2-3) to (a1-2-4) and the following formulas (a1-2-2) The monomers represented by 9) to (a1-2-10) are more preferable, and the monomers represented by the following formula (a1-2-3) and the following formula (a1-2-9) are more preferable.

  When resin (A2) contains structural unit (a1-1) and / or structural unit (a1-2), these total content rates are 10-95 mol normally with respect to all the structural units of resin (A2). %, Preferably 15 to 90 mol%, more preferably 20 to 85 mol%.

<Acid stable monomer>
As an acid stable monomer, Preferably, the monomer which has a hydroxyl group or a lactone ring is mentioned. Acid-stable monomer having a hydroxy group (hereinafter sometimes referred to as “acid-stable monomer having a hydroxy group (a2)”) or 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 derived from (sometimes) is used, the resolution of the resist pattern 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), high energy beam exposure such as electron beam or EUV light, the acid-stable monomer (a2) having a hydroxy group is preferably a phenolic hydroxy which is a hydroxystyrene. An acid-stable monomer having a group is used. When using short-wavelength ArF excimer laser exposure (193 nm) or the like, the acid-stable monomer (a2) having a hydroxy group is preferably an acid-stable monomer having a hydroxyadamantyl group represented by the formula (a2-1). use. The acid-stable monomer (a2) having a hydroxy group may be used alone or in combination of two or more.

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

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

In 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 monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned, for example. Monomers represented by the following formulas (a2-1-1) to (a2-1-6) are preferred, and monomers represented by the following formulas (a2-1-1) to (a2-1-4) are more preferred. A monomer represented by the following formula (a2-1-1) or (a2-1-3) is more preferable.

  When the resin (A2) includes a structural unit derived from the monomer represented by the formula (a2-1), the content is usually 3 to 45 mol% with respect to all the structural units of the resin (A2). , Preferably it is 3-40 mol%, More preferably, it is 3-35 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 or a condensed ring of γ-butyrolactone ring and another ring is 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のアルキル基を表す。
ｐ１は０〜５の整数を表す。
Ｒ^a22及びＲ^a23は、それぞれ独立に、カルボキシ基、シアノ基又は炭素数１〜４のアルキル基を表す。
ｑ１及びｒ１は、それぞれ独立に０〜３の整数を表す。ｐ１、ｑ１又はｒ１が２以上のとき、それぞれ、複数のＲ^a21、Ｒ^a22又はＲ^a23は、同一又は相異なる。

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 alkyl group having 1 to 4 carbon atoms.
p1 represents an integer of 0 to 5.
R ^a22 and R ^a23 each independently represent a carboxy group, a cyano group, or an alkyl group having 1 to 4 carbon atoms.
q1 and r1 each independently represents an integer of 0 to 3. When p1, q1 or r1 is 2 or more, a plurality of R ^a21 , R ^a22 or R ^a23 are the same or different, respectively.

^Examples of the alkyl group represented by R ^{a21 to} R ^a23 include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, and a sec-butyl group.

In formula (a3-1) to formula (a3-3), L ^{a4 to} L ^a6 are preferably each independently —O— or ^* —O— (CH ₂ ) _k3 —CO—O—, More preferably, it is -O-. k3 is preferably an integer of 1 to 4, more preferably 1.
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 to r1 are each independently preferably 0 to 2, more preferably 0 or 1.

  Examples of the acid-stable monomer (a3) having a lactone ring include monomers described in JP 2010-204646 A. In the following formulas (a3-1-1) to (a3-1-4), (a3-2-1) to (a3-2-4), (a3-3-1) to (a3-3-4) Monomers represented by the following formulas (a3-1-1) to (a3-1-2) and (a3-2-3) to (a3-2-4) are more preferred, A monomer represented by formula (a3-1-1) or (a3-2-3) is more preferable.

  When the resin (A2) includes a structural unit derived from the acid-stable monomer (a3) having a lactone ring, the total content is usually 5 to 70 mol% with respect to all the structural units of the resin (A2). , Preferably it is 10-65 mol%, More preferably, it is 10-60 mol%.

When the resin (A2) is a copolymer of an acid labile monomer (a1) and an acid stable monomer, the structural unit derived from the acid labile monomer (a1) is based on 100 mol% of all structural units. Preferably it is 10-80 mol%, More preferably, it is 20-60 mol%.
The content of the structural unit derived from the monomer having an adamantyl group (particularly the structural unit (a1-1)) is preferably 15 mol% or more based on the total of the structural units derived from the acid labile monomer (a1). is there. When the ratio of the structural unit derived from the monomer having an adamantyl group is increased, the dry etching resistance of the resist pattern is improved.

  The resin (A2) is preferably a copolymer of a monomer represented by the formula (II ′), an acid labile monomer (a1), and an acid stable monomer. In this copolymer, the acid labile monomer (a1) is more preferably at least one of the monomer (a1-1) having an adamantyl group and the monomer (a1-2) (preferably the monomer having a cyclohexyl group or a cyclopentyl group). One type, more preferably monomer (a1-1). The acid stable monomer is preferably an acid stable monomer (a2) having a hydroxy group and / or an acid stable monomer (a3) having a lactone ring. The acid-stable monomer (a2) having a hydroxy group is preferably an acid-stable monomer (a2-1) having a hydroxyadamantyl group, and the acid-stable monomer (a3) having a lactone ring is more preferably a γ-butyrolactone ring. The acid-stable monomer (a3-1) and the acid-stable monomer (a3-2) having a condensed ring of a γ-butyrolactone ring and a norbornane ring.

Each structural unit constituting the resin (A2) may be used alone or in combination of two or more, and is produced by a known polymerization method (for example, radical polymerization method) using a monomer that derives these structural units. can do.
The weight average molecular weight of the resin (A2) is preferably 2,500 or more (more preferably 3,000 or more, more preferably 4,000 or more), 50,000 or less (more preferably 30,000 or less, further preferably 15,000 or less).
Resin (A1) and resin (A2) in resin (A) are, for example, 0.01: 10 to 5:10, preferably 0.05: 10 to 3:10, more preferably 0.1: 10. It is contained at 2:10, particularly preferably 0.2: 10 to 1:10 (mass ratio).

<Resin other than resin (A1) and (A2)>
The resist composition of the present invention includes resins other than the resins (A1) and (A2) described above, for example, structural units derived from the acid labile monomer (a1) described above, structural units derived from the acid stable monomer, and the like. Further, a resin composed of a structural unit derived from a known monomer used in the field may be contained.
When the resist composition of this invention contains resin other than resin (A1) and (A2), these content rates are normal with respect to the total amount of resin (A) contained in the resist composition of this invention. It is 0.1-50 mass%, Preferably it is 0.5-30 mass%, More preferably, it is 1-20 mass%.

  In the resist composition of the present invention, the resin content is preferably 80% by mass or more in the solid content of the resist 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, for example, by a known analysis means such as liquid chromatography or gas chromatography.

<Acid generator (B)>
The acid generator (B) is classified into a nonionic type and an ionic type, and any of them may be used in the resist composition of the present invention. Examples of the nonionic acid generator include organic halides, sulfonate esters (for example, 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4). -Sulfonate), sulfones (for example, disulfone, ketosulfone, sulfonyldiazomethane) and the like. Examples of the ionic acid generator include onium salts containing onium cations (for example, diazonium salts, phosphonium salts, sulfonium salts, iodonium salts) and the like. Examples of the anion of the onium salt include a sulfonate anion, a sulfonylimide anion, and a sulfonylmethide anion.

  Examples of the acid generator (B) include JP-A 63-26653, JP-A 55-164824, JP-A 62-69263, JP-A 63-146038, JP-A 63-163452, JP-A-62-153853, JP-A-63-146029, US Pat. No. 3,779,778, US Pat. No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712 The compound which generate | occur | produces an acid by the radiation as described in etc. can be used.

  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２価の炭素数１〜１７の飽和炭化水素基を表し、前記２価の飽和炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−又は−ＣＯ−で置き換わっていてもよい。
Ｙは、置換基を有していてもよい炭素数１〜１８のアルキル基又は置換基を有していてもよい炭素数３〜１８の脂環式炭化水素基を表し、前記アルキル基及び前記脂環式炭化水素基に含まれる−ＣＨ_２−は、−Ｏ−、−ＳＯ_２−又は−ＣＯ−で置き換わっていてもよい。
Ｚ⁺は、有機カチオンを表す。］

[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 alkyl group having 1 to 18 carbon atoms which may have a substituent or an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, and the alkyl group and the above —CH ₂ — contained in the alicyclic hydrocarbon group may be replaced by —O—, —SO ₂ — or —CO—.
Z ⁺ represents an organic cation. ]

Examples of the perfluoroalkyl group of Q ¹ and Q ² include a trifluoromethyl 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. And perfluorohexyl group.
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 for L ^b1 include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and these A combination of two or more of the groups may be used.
Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1 , 6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group , Dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1, Linear alkanediyl groups such as 17-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group and propane-2,2-diyl group;
An alkyl group (particularly an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group); For example, 1-methylbutane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4 A branched alkanediyl group such as a diyl group or 2-methylbutane-1,4-diyl group;
Monocyclic 2 which is a cycloalkanediyl group such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group Valent alicyclic saturated hydrocarbon group;
Polycyclic divalent alicyclic saturated hydrocarbon such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. Groups and the like.

Examples of the group in which —CH ₂ — contained in the saturated hydrocarbon group of L ^b1 is replaced by —O— or —CO— include formula (b1-1) to formula (b1-6). The formula (b1-1) to the formula (b1-6) are written in accordance with the formula (B1) on the left and right sides, and C (Q ¹ ) on the left side of two bonds represented by *, respectively. (Q ² ) Bonded to-and bonded to -Y on the right side. 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、Ｌ^b1は、好ましくは式（ｂ１−１）〜式（ｂ１−４）のいずれか、より好ましくは式（ｂ１−１）又は式（ｂ１−２）、さらに好ましくは式（ｂ１−１）で表される２価の基である。特に、好ましくはＬ^b2が単結合又は−ＣＨ_２−である式（ｂ１−１）で表される２価の基である。

In formula (b1-1) to formula (b1-6),
L ^b2 represents a single bond or a divalent saturated hydrocarbon group having 1 to 15 carbon atoms.
L ^b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 12 carbon atoms.
L ^b4 represents a 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 them, L ^b1 is preferably any one of formula (b1-1) to formula (b1-4), more preferably formula (b1-1) or formula (b1-2), and still more preferably formula (b1-1). ) Represented by a divalent group. Particularly preferred is a divalent group represented by the formula (b1-1), wherein L ^b2 is a single bond or —CH ₂ —.

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

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

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

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

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

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

Examples of the alkyl group for Y 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 -Alkyl groups, such as an ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, are mentioned, Preferably, a C1-C6 alkyl group is mentioned.
Examples of the alicyclic hydrocarbon group include groups represented by the following formulas (Y1) to (Y11).
Examples of the group in which —CH ₂ — contained in the alicyclic hydrocarbon group of Y is replaced by —O—, —SO ₂ — or —CO— are represented by formulas (Y12) to (Y26). Groups.

  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 the substituent of the alkyl group and alicyclic hydrocarbon group in Y include, for example, a halogen atom, a hydroxy group, an oxo group, an alkyl group having 1 to 12 carbon atoms, a hydroxy group-containing alkyl group having 1 to 12 carbon atoms, carbon C3-C16 alicyclic hydrocarbon group, C1-C12 alkoxy group, C6-C18 aromatic hydrocarbon group, C7-C21 aralkyl group, C2-C4 acyl group , Glycidyloxy group or — (CH ₂ ) _j2 —O—CO—R ^b1 group (wherein R ^b1 is an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, or carbon Represents an aromatic hydrocarbon group of formula 6 to 18. j2 represents an integer of 0 to 4. The alkyl group, alicyclic 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 halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
Examples of the hydroxy group-containing alkyl group include a hydroxymethyl group and a hydroxyethyl group.
Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy group.
Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group; tolyl group, xylyl group, cumenyl group, mesityl group. , Aryl groups such as biphenyl 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 Y include the following.

When Y is an alkyl group and L ^b1 is a divalent aliphatic hydrocarbon group having 1 to 17 carbon atoms, the methylene group of the divalent aliphatic hydrocarbon group bonded to Y is oxygen It is preferably replaced by an atom or a carbonyl group. In this case, the methylene group constituting the alkyl group of Y is not replaced with an oxygen atom or a carbonyl group.

  Y is preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, more preferably a substituent (for example, an oxo group, a hydroxy group, etc.). A good adamantyl group, more preferably an adamantyl group, a hydroxyadamantyl group or an oxoadamantyl group.

The sulfonate anion in the salt represented by the formula (B1) is preferably an anion represented by the formula (b1-1-1) to the formula (b1-1-9). In the following formulas, the definitions of the symbols have the same meaning as described above, and R ^b2 and R ^b3 each independently represent an alkyl group having 1 to 4 carbon atoms (preferably a methyl group).
Specific examples of the sulfonate anion in the salt represented by the formula (B1) include the anions described in JP 2010-204646 A.

Examples of the organic cation (Z ⁺ ) contained in the acid generator (B1) include organic onium cations such as organic sulfonium cation, organic iodonium cation, organic ammonium cation, benzothiazolium cation, and organic phosphonium cation. Is an organic sulfonium cation or an organic iodonium cation, and more preferably an arylsulfonium cation.

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

In formula (b2-1) to formula (b2-4),
R ^{b4 to} R ^b6 each independently represents a hydrocarbon group having 1 to 30 carbon atoms, and this hydrocarbon group is an alkyl group having 1 to 30 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms. And an aromatic hydrocarbon group having 6 to 18 carbon atoms. The alkyl group may have 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 alicyclic hydrocarbon group includes a halogen atom and a carbon number. The aromatic hydrocarbon group may have 2 to 4 acyl groups or glycidyloxy groups, and the aromatic hydrocarbon group is a halogen atom, a hydroxy group, an alkyl group having 1 to 18 carbon atoms, or an alicyclic group having 3 to 18 carbon atoms. You may have a hydrocarbon group or a C1-C12 alkoxy group. R ^b4 and R ^b5 may be combined to form a ring that may have a hetero atom.
R ^b7 and R ^b8 each independently represent a hydroxy group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
m2 and n2 each independently represents an integer of 0 to 5, and when m2 is 2 or more, the plurality of R ^b7 are the same or different, and when n2 is 2 or more, the plurality of R ^b8 are the same or Different.
R ^b9 and R ^b10 each independently represent an alkyl group having 1 to 18 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or R ^b9 and R ^b10 are a sulfur atom to which they are bonded. Together with each other to form a 3- to 12-membered ring (preferably a 3- to 7-membered ring). The methylene group contained in the ring may be replaced with an oxygen atom, a sulfur atom or a carbonyl group.
R ^b11 represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.
R ^b11 and R ^b12 may form a 3- to 12-membered ring (preferably a 3- to 7-membered ring) with —CH—CO— to which they are bonded. The methylene group contained in the ring may be replaced with an oxygen atom, a sulfur atom or a carbonyl group.
R ^b12 represents an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the aromatic hydrocarbon group has It may be substituted with an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an alkylcarbonyloxy group having 1 to 12 carbon atoms.

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

芳香族炭化水素基としては、フェニル基、ナフチル基、アントリル基、ｐ−メチルフェニル基、ｐ−ｔｅｒｔ−ブチルフェニル基、ｐ−アダマンチルフェニル基、トリル基、キシリル基、クメニル基、メシチル基、ビフェニル基、フェナントリル基、２，６−ジエチルフェニル基、２−メチル−６−エチルフェニル等のアリール基等が挙げられる。 Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. .
The alicyclic hydrocarbon group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, and dimethylcyclohexane. Examples thereof include a cycloalkyl group such as a hexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic saturated hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, a methylnorbornyl group, and the following groups. * Represents a bond with an adamantane ring or a cyclohexane ring.

Aromatic hydrocarbon groups include phenyl, naphthyl, anthryl, p-methylphenyl, p-tert-butylphenyl, p-adamantylphenyl, tolyl, xylyl, cumenyl, mesityl, biphenyl Groups, phenanthryl groups, 2,6-diethylphenyl groups, aryl groups such as 2-methyl-6-ethylphenyl, and the like.

Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
Examples of the acyl group include an acetyl group, a propionyl group, and a butyryl group.
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.

The alkyl group of R ^{b9 to} R ^b12 preferably has 1 to 12 carbon atoms, and in particular, a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group , A pentyl group, a hexyl group, an octyl group and a 2-ethylhexyl group are preferred.
The alicyclic hydrocarbon group of R ^{b9 to} R ^b11 preferably has 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms, and in particular, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl. Group, cyclodecyl group, 2-alkyladamantan-2-yl group, 1- (adamantan-1-yl) alkane-1-yl group and isobornyl group are preferable.
The aromatic hydrocarbon group for R ^b12 includes a phenyl group, a 4-methylphenyl group, a 4-ethylphenyl group, a 4-tert-butylphenyl group, a 4-cyclohexylphenyl group, a 4-methoxyphenyl group, a biphenylyl group, and A naphthyl group and the like are preferable.
A group in which an aromatic hydrocarbon group of R ^b12 and an alkyl group are bonded is typically an aralkyl group.

The ring containing a sulfur atom which R ^b4 and R ^b5 may form together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. If it contains one or more sulfur atoms, it may further contain one or more sulfur atoms and / or one or more oxygen atoms. As the ring, a ring having 3 to 18 carbon atoms is preferable, and a ring having 4 to 13 carbon atoms is more preferable.

Examples of the ring formed together with the sulfur atom to which R ^b9 and R ^b10 are bonded include, for example, a thiolane-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, and 1,4-oxathian-4-ium. A ring etc. are mentioned.
Examples of the ring formed with —CH—CO— in which R ^b11 and R ^b12 are bonded 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, and the cation represented by the formula (b2-1-1) is more preferable. Are triphenylsulfonium cations (in formula (b2-1-1), v2 = w2 = x2 = 0), diphenyltolylsulfonium cations (in formula (b2-1-1), v2 = w2 = 0, x2 = 1 And R ^b21 is a methyl group.) Or a tolylsulfonium cation (in formula (b2-1-1), v2 = w2 = x2 = 1, and R ^b19 , R ^b20 and R ^b21 are all methyl. Group.)

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１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１８の脂環式炭化水素基を表す。また、Ｒ^b19〜Ｒ^b21から選ばれる２つが一緒になってヘテロ原子を有してもよい環を形成してもよい。
ｖ２、ｗ２及びｘ２は、それぞれ独立に０〜５の整数（好ましくは０又は１）を表す。
ｖ２が２以上のとき、複数のＲ^b19は同一又は相異なり、ｗ２が２以上のとき、複数のＲ^b20は同一又は相異なり、ｘ２が２以上のとき、複数のＲ^b21は同一又は相異なる。
なかでも、Ｒ^b19、Ｒ^b20及びＲ^b21は、それぞれ独立に、好ましくは、ハロゲン原子（より好ましくはフッ素原子）、ヒドロキシ基、炭素数１〜１２のアルキル基、又は炭素数１〜１２のアルコキシ基である。

In formula (b2-1-1),
R ^{b19 to} R ^b21 are each independently a halogen atom (more preferably a fluorine atom) hydroxy group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alicyclic group having 3 to 18 carbon atoms. Represents a hydrocarbon group. It is also possible to form two of which may have a hetero atom together ring selected from R ^b19 to R ^b21.
v2, w2 and x2 each independently represent an integer of 0 to 5 (preferably 0 or 1).
When v2 is 2 or more, the plurality of R ^b19 are the same or different, when w2 is 2 or more, the plurality of R ^b20 are the same or different, and when x2 is 2 or more, the plurality of R ^b21 are the same or different. .
Among them, R ^b19 , R ^b20 and R ^b21 are preferably each independently a halogen atom (more preferably a fluorine atom), a hydroxy group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. It is a group.

  Specific examples of the cation include those described in JP2010-204646A.

  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, and preferably a combination of any one of anion (b1-1-1) to anion (b1-1-9) and cation (b2-1-1), and A combination of any one of anions (b1-1-3) to (b1-1-5) and a cation (b2-3) may be mentioned.

  The acid generator (B1) is preferably a salt represented by the formula (B1-1) to the formula (B1-20), more preferably a salt containing a triphenylsulfonium cation or a tolylsulfonium cation. More preferably, Formula (B1-1), Formula (B1-2), Formula (B1-3), Formula (B1-6), Formula (B1-7), Formula (B1-11), Examples thereof include salts represented by formula (B1-12), formula (B1-13) and formula (B1-14).

The content of the acid generator (B) is preferably 1 part by mass or more (more preferably 3 parts by mass or more), preferably 30 parts by mass or less (more preferably 25 parts by mass) with respect to 100 parts by mass of the resin (A). Part or less).
In the resist composition of the present invention, the acid generator (B) may contain a single acid generator or a plurality of acid generators at the same time.

<Solvent (E)>
The content rate of the solvent (E) contained in the resist composition of this invention is 90 mass% or more in a resist composition, for example, Preferably it is 92 mass% or more, More preferably, it is 94 mass% or more, for example, 99.9. It is not more than mass%, preferably not more than 99 mass%. The content rate of a solvent (E) can be measured by well-known analysis means, such as a liquid chromatography or a gas chromatography, for example.

  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 contain 1 type independently, and may contain 2 or more types.

<Basic compound (hereinafter sometimes referred to as “basic compound (C)”)>
The basic compound (C) is a compound that acts as a quencher.
The basic compound (C) is preferably a basic nitrogen-containing organic compound, and examples thereof include amines and ammonium salts. Examples of amines include aliphatic amines and aromatic amines. Aliphatic amines include primary amines, secondary amines and tertiary amines. The basic compound (C) is preferably a compound represented by the formula (C1) to a compound represented by the formula (C8), more preferably a compound represented by the formula (C1-1). It is done.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

  The content of the basic compound (C) is preferably about 0.01 to 5% by mass, more preferably about 0.01 to 3% by mass, and particularly preferably based on the solid content of the resist composition. It is about 0.01-1 mass%.

<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 other component (F) is not particularly limited, and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, and the like can be used.

<Preparation of resist composition>
The resist composition of the present invention comprises a resin (A) containing a resin (A1) and a resin (A2), an acid generator (B), a solvent (E) used as necessary, a basic compound (C) and It can prepare by mixing another component (F). The mixing order is arbitrary and is not particularly limited. The temperature at the time of mixing can select an appropriate temperature range from the range of 10-40 degreeC according to the kind etc. of resin, the solubility with respect to solvent (E), such as resin. An appropriate mixing time can be selected from 0.5 to 24 hours depending on the mixing temperature. The mixing means is not particularly limited, and stirring and mixing can be used.
After mixing each component, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm.

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

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

By drying the composition after coating, the solvent is removed and a composition layer is formed. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking) or using a decompression device to form a composition layer from which the solvent has been removed. The temperature in this case is preferably about 50 to 200 ° C., for example. The pressure is preferably about 1 to 1.0 × 10 ⁵ Pa.

The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. 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.) Using various lasers such as those that convert wavelength of laser light from the laser and emit harmonic laser light in the far-ultraviolet region or vacuum ultraviolet region, those that irradiate electron beams or extreme ultraviolet light (EUV), etc. Can do.

The composition layer after exposure is subjected to heat treatment (so-called post-exposure baking) in order to promote 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 a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, particularly a liquid. It is suitable as a resist composition for immersion exposure and useful for fine processing of semiconductors.

The present invention will be described more specifically with reference to examples. In the examples, “%” and “parts” representing the content or amount used are based on mass unless otherwise specified. The composition ratio of the resin (A) (copolymerization ratio of the structural unit derived from each monomer used for the production of the resin (A) to the resin (A)) is the amount of unreacted monomer in the reaction liquid after the polymerization is finished. It measured using the chromatography, and computed by calculating | requiring the monomer amount used for superposition | polymerization from the obtained result. The weight average molecular weight is a value determined by gel permeation chromatography. The analysis conditions for gel permeation chromatography are as follows.
Apparatus: HLC-8120GPC type (manufactured by Tosoh Corporation)
Column: TSKgel Multipore HXL-M x 3 + guardcolumn (manufactured by Tosoh Corporation)
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min
Detector: RI detector Column temperature: 40 ° C
Injection volume: 100 μl
Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation)

式（Ｈ−１）で表される化合物２５部、テトラヒドロフラン１７５部及びピリジン１１．８６部を仕込み、２３℃で３０分間攪拌した後、５℃に冷却し、式（Ｈ−２）で表される化合物１４．８２部を３０分かけて添加した。５℃で１時間攪拌した後、酢酸エチル３４０部、５％塩酸６６部及びイオン交換水８５部を添加し、攪拌後、分液を行った。回収された有機層に、１０％炭酸カリウム水溶液５５部を添加し、攪拌後、分液を行った。回収された有機層に、イオン交換水８５部を添加し、攪拌後、分液を行った。この水洗の操作を５回行った。回収された有機層を濃縮することにより、式（Ｈ−３）で表される化合物２８．６２部を得た。

式（Ｈ−４）で表される化合物１０．６９部、ジメチルホルムアミド５３．４７部、炭酸カリウム８．５８部及びヨウ化カリウム１．０３部を仕込み、４０℃で１時間攪拌した後、式（Ｈ−３）で表される化合物２８．６２部及びジメチルホルムアミド５７．２４部の混合溶液を３０分かけて添加した。４０℃で６時間攪拌した後、２３℃まで冷却した。得られた反応マスに、クロロホルム６７０部及び５％シュウ酸水溶液１６６部を添加し、攪拌後、分液を行った。回収された有機層に、イオン交換水２６５部を添加し、攪拌後、分液を行った。この水洗の操作を６回行った。回収された有機層を濃縮した後、得られた濃縮マスに、アセトニトリル７．５８部及び酢酸エチル２６．５３部を添加、３時間攪拌した後、ろ過することにより、式（Ｈ）で表される化合物３２．１３部を得た。 Synthesis Example 1: Synthesis of compound represented by formula (H)

25 parts of the compound represented by the formula (H-1), 175 parts of tetrahydrofuran and 11.86 parts of pyridine were charged, stirred at 23 ° C. for 30 minutes, cooled to 5 ° C., and represented by the formula (H-2). 14.82 parts of the above compound was added over 30 minutes. After stirring at 5 ° C. for 1 hour, 340 parts of ethyl acetate, 66 parts of 5% hydrochloric acid and 85 parts of ion-exchanged water were added, followed by liquid separation after stirring. To the collected organic layer, 55 parts of a 10% potassium carbonate aqueous solution was added, and after separation, liquid separation was performed. To the recovered organic layer, 85 parts of ion-exchanged water was added, followed by liquid separation after stirring. This washing operation was performed 5 times. By concentrating the collected organic layer, 28.62 parts of a compound represented by the formula (H-3) was obtained.

10.69 parts of the compound represented by the formula (H-4), 53.47 parts of dimethylformamide, 8.58 parts of potassium carbonate and 1.03 parts of potassium iodide were charged and stirred at 40 ° C. for 1 hour. A mixed solution of 28.62 parts of the compound represented by (H-3) and 57.24 parts of dimethylformamide was added over 30 minutes. After stirring at 40 ° C. for 6 hours, the mixture was cooled to 23 ° C. To the obtained reaction mass, 670 parts of chloroform and 166 parts of a 5% aqueous oxalic acid solution were added, followed by liquid separation after stirring. To the collected organic layer, 265 parts of ion-exchanged water was added, followed by liquid separation after stirring. This washing operation was performed 6 times. After the collected organic layer was concentrated, 7.58 parts of acetonitrile and 26.53 parts of ethyl acetate were added to the resulting concentrated mass, and the mixture was stirred for 3 hours, and then filtered, and expressed by the formula (H). 32.13 parts of compound were obtained.

式（Ｍ−１）で表される化合物３３．２５部、ジシクロヘキシルカルボジイミド２３．９３部及び塩化メチレン４０．００部を、反応器に仕込み混合した。混合物を０℃程度まで冷却した後、式（Ｍ−２）で表される化合物１８．８３部を加え、０℃程度のまま、１時間攪拌した。２３℃まで昇温し、さらに３０分間攪拌した。不溶物をろ過して除去し、得られたろ液を濃縮して、式（Ｍ−３）で表される化合物４４．１９部を得た。 Synthesis Example 2 [Synthesis of Compound Represented by Formula (M)]

33.25 parts of the compound represented by the formula (M-1), 23.93 parts of dicyclohexylcarbodiimide and 40.00 parts of methylene chloride were charged into a reactor and mixed. After the mixture was cooled to about 0 ° C., 18.83 parts of the compound represented by the formula (M-2) was added, and the mixture was stirred for 1 hour while maintaining about 0 ° C. The temperature was raised to 23 ° C., and the mixture was further stirred for 30 minutes. Insoluble matters were removed by filtration, and the obtained filtrate was concentrated to obtain 44.19 parts of a compound represented by the formula (M-3).

このようにして得られた式（Ｍ−３）で表される化合物１９．３３部、式（Ｍ−４）で表される化合物１９．０２部及びアセトニトリル２００部を、反応器に仕込んで混合し、この混合物を５０℃で３時間攪拌した。得られた混合物を濃縮し、クロロホルム３００部及びイオン交換水１５０部を加え、分液操作により、有機層を回収した。回収された有機層をイオン交換水１５０部で水洗し、有機層を濃縮した。濃縮物を、カラム分取（カラム分取条件 固定相：メルク社製シリカゲル６０−２００メッシュ 展開溶媒：酢酸エチル）することにより、式（Ｍ）で表される化合物１４．５８部を得た。
ＭＳ（質量分析）：３１５．１（分子イオンピーク）

19.33 parts of the compound represented by the formula (M-3) thus obtained, 19.02 parts of the compound represented by the formula (M-4) and 200 parts of acetonitrile were charged into a reactor and mixed. The mixture was stirred at 50 ° C. for 3 hours. The obtained mixture was concentrated, 300 parts of chloroform and 150 parts of ion-exchanged water were added, and the organic layer was recovered by a liquid separation operation. The recovered organic layer was washed with 150 parts of ion exchange water, and the organic layer was concentrated. The concentrate was subjected to column fractionation (column fractionation conditions stationary phase: silica gel 60-200 mesh manufactured by Merck & Co., Ltd. developing solvent: ethyl acetate) to obtain 14.58 parts of a compound represented by the formula (M).
MS (mass spectrometry): 315.1 (molecular ion peak)

Resin synthesis Monomers used in resin synthesis are shown below.

[Synthesis of Resin A1-1]
Monomer (H) and monomer (I) are used as monomers and mixed so that the molar ratio (monomer (H): monomer (I)) is 90:10. Dioxane was added to make a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators are added to the solution, respectively, and heated at 72 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of n-heptane to precipitate a resin, and this resin was filtered to obtain a resin A1-1 (copolymer) having a weight average molecular weight of 1.4 × 10 ^{4 in} a yield of 75%. Got in. This resin A1-1 has the following structural units.

[Synthesis of Resin A1-2]
Monomer (H) was used as a monomer, and 1.5 mass times dioxane of the total monomer amount was added to prepare a solution. To this solution, 0.7 mol% and 2.1 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile), respectively, as initiators were added with respect to the total monomer amount, and these were added at 75 ° C. Heated for about 5 hours. The obtained reaction mixture was poured into a large amount of n-heptane to precipitate a resin, and this resin was filtered to obtain a resin A1-2 having a weight average molecular weight of 1.8 × 10 ^{4 in} a yield of 75%. This resin A1-2 has the following structural units.

[Synthesis of Resin A2-1]

As a monomer, a monomer (D), a monomer (E), a monomer (B), a monomer (C), and a monomer (M) are mixed in a molar ratio [monomer (D): monomer (E): monomer (B): monomer ( C): monomer (M)] was mixed at 35: 10: 6: 37: 12, and 1.5 mass times dioxane of the total monomer amount was added to obtain a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators are added to the solution, respectively, with respect to the total monomer amount, and these are heated at 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The resin thus obtained is again dissolved in dioxane, and a solution obtained by pouring the solution into a methanol / water mixed solvent is precipitated twice, and the resin is filtered twice to perform a reprecipitation operation twice. 2 × 10 ³ resin A2-1 (copolymer) was obtained with a yield of 65%. This resin A2-1 has the following structural units.

[Synthesis of Resin A2-2]
As a monomer, a monomer (D), a monomer (E), a monomer (B), a monomer (F), a monomer (C), and a monomer (M) are mixed in a molar ratio [monomer (D): monomer (E): monomer ( B): monomer (F): monomer (C): monomer (M)] is mixed to 35: 10: 8: 12: 23: 12, and 1.5 mass times of dioxane is added to the total amount of monomers. Solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators are added to the solution, respectively, with respect to the total monomer amount, and these are heated at 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The resin thus obtained is again dissolved in dioxane, and a solution obtained by pouring the solution into a methanol / water mixed solvent is precipitated twice, and the resin is filtered twice to perform a reprecipitation operation twice. 4 × 10 ³ resin A2-2 (copolymer) was obtained with a yield of 66%. This resin A2-2 has the following structural units.

[Synthesis of Resin A2-3]
As a monomer, a monomer (A), a monomer (E), a monomer (B), a monomer (C), and a monomer (M) are mixed in a molar ratio [monomer (A): monomer (E): monomer (B): monomer ( C): monomer (M)] was 32: 7: 8: 43: 10, and 1.5 mass times dioxane of the total monomer amount was added to obtain a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators are added to the solution, respectively, with respect to the total monomer amount, and these are heated at 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The resin thus obtained is again dissolved in dioxane, and a solution obtained by pouring the solution into a methanol / water mixed solvent is precipitated twice, and the resin is filtered twice to perform a reprecipitation operation twice. 5 × 10 ³ resin A2-3 (copolymer) was obtained with a yield of 78%. This resin A2-3 has the following structural units.

[Synthesis of Resin A2-4]
As a monomer, a monomer (D), a monomer (E), a monomer (B), a monomer (F), a monomer (C), and a monomer (M) are mixed in a molar ratio [monomer (D): monomer (E): monomer ( B): monomer (F): monomer (C): monomer (M)] is mixed to be 30: 14: 6: 10: 30: 10, and 1.5 mass times the total amount of dioxane is added. Solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators are added to the solution, respectively, with respect to the total monomer amount, and these are heated at 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The resin thus obtained is again dissolved in dioxane, and a solution obtained by pouring the solution into a methanol / water mixed solvent is precipitated twice, and the resin is filtered twice to perform a reprecipitation operation twice. 8 × 10 ³ resin A2-4 (copolymer) was obtained with a yield of 60%. This resin A2-4 has the following structural units.

[Synthesis of Resin A2-5]
As a monomer, a monomer (D), a monomer (N), a monomer (B), a monomer (F), a monomer (C), and a monomer (M) are mixed at a molar ratio [monomer (D): monomer (N): monomer ( B): monomer (F): monomer (C): monomer (M)] is mixed to be 30: 14: 6: 10: 30: 10, and 1.5 mass times the total amount of dioxane is added. Solution. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and these were heated at 73 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The obtained resin was dissolved again in dioxane, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by reprecipitation operation of filtering the resin twice, and a weight average molecular weight of 8.0. × 10 ³ of the resin A2-5 (copolymer) was obtained in 66% yield. This resin A2-5 has the following structural units.

[Synthesis of Resin A2-6]
As a monomer, a monomer (D), a monomer (N), a monomer (O), a monomer (F), a monomer (C), and a monomer (M) are mixed in a molar ratio [monomer (D): monomer (N): monomer ( O): monomer (F): monomer (C): monomer (M)] is mixed to 35: 12: 3: 10: 30: 10, and 1.5 mass times dioxane of the total monomer amount is added. Solution. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and these were heated at 73 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The resin obtained was dissolved again in dioxane, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by two reprecipitation operations of filtering the resin, and a weight average molecular weight of 8.2. A x10 ³ resin A2-6 (copolymer) was obtained in a yield of 64%. This resin A2-6 has the following structural units.

[Synthesis of Resin X1]
Monomer (G), monomer (C), and monomer (B) are used as the monomers and mixed so that the molar ratio (monomer (G): monomer (C): monomer (B)) is 35:45:20. Then, 1.5 mass times dioxane of the total monomer amount was added to make a solution. To the solution, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added at 1.0 mol% and 3.0 mol%, respectively, with respect to the total monomer amount, and these were added at 75 ° C. Heated for about 5 hours. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The resin thus obtained is again dissolved in dioxane, and a solution obtained by pouring the solution into a methanol / water mixed solvent is precipitated twice, and the resin is filtered twice to perform a reprecipitation operation twice. 0 × 10 ³ resin X1 (copolymer) was obtained in a yield of 75%. This resin X1 has the following structural units.

[Synthesis of Resin X2]
As the monomer, the monomer (J) and the monomer (G) are used and mixed so that the molar ratio (monomer (J): monomer (G)) is 80:20. Dioxane was added to make a solution. To the solution, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 0.5 mol% and 1.5 mol%, respectively, based on the total monomer amount, and these were added at 70 ° C. Heated for about 5 hours. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The resin thus obtained is again dissolved in dioxane, and a solution obtained by pouring the solution into a methanol / water mixed solvent is precipitated twice, and the resin is filtered twice to perform a reprecipitation operation twice. 8 × 10 ⁴ resin X2 (copolymer) was obtained with a yield of 70%. This resin X2 has the following structural units.

[Synthesis of Resin X3]
As the monomer, the monomer (D), the monomer (B), the monomer (C), and the monomer (L) have a molar ratio [monomer (D): monomer (B): monomer (C): monomer (L)] of 51. 7: 7.8: 23.3: 17.2, and 1.5 mass times the total monomer amount of dioxane was added to obtain a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators are added to the solution, respectively, with respect to the total monomer amount, and these are heated at 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The resin thus obtained is again dissolved in dioxane, and a solution obtained by pouring the solution into a methanol / water mixed solvent is precipitated twice, and the resin is filtered twice to perform a reprecipitation operation twice. 7 × 10 ³ resin X3 (copolymer) was obtained in a yield of 64%. This resin X3 has the following structural units.

<Preparation of resist composition>
A mixture obtained by mixing and dissolving the components shown in Table 1 was filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

Ｂ２：ＷＯ２００８／９９８６９号の実施例及び、特開２０１０−２６４７８の実施例に従って合成

Ｂ３：特開２００５−２２１７２１の実施例に従って合成

Ｂ４：特開２０１０−１１３３３４の実施例に従って合成

<Resin>
Resins A1-1, A1-2, A2-1 to A2-6, X1 to X3 synthesized in the synthesis example described above
<Acid generator>
B1: Synthesis according to the example of JP 2010-152341 A

B2: synthesized according to examples of WO2008 / 99869 and JP2010-26478

B3: synthesized according to the example of JP-A-2005-221721

B4: synthesized according to the example of JP 2010-113334 A

<Basic compound: Quencher>
C1: 2,6-diisopropylaniline (manufactured by Tokyo Chemical Industry Co., Ltd.)

<Solvent>
Propylene glycol monomethyl ether acetate 265.0 parts Propylene glycol monomethyl ether 20.0 parts 2-heptanone 20.0 parts γ-butyrolactone 3.5 parts

<Immersion exposure evaluation of resist composition>
An organic antireflective coating composition [ARC-29; manufactured by Nissan Chemical Industries, Ltd.] was applied onto a 12-inch silicon wafer and baked at 205 ° C. for 60 seconds to obtain a thickness of 78 nm. 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 (pre-baking) was 85 nm.
After coating the resist composition, the obtained silicon wafer was pre-baked (PB) for 60 seconds at a temperature described in the “PB” column of Table 1 on a direct hot plate to form a composition layer. The wafer having the resist composition film thus formed was immersed in an ArF excimer stepper for immersion exposure (XT: 1900 Gi; manufactured by ASML, NA = 1.35, 3/4 Annular XY polarized light), and contact hole pattern (hole pitch 100 nm). Using a mask for forming a hole diameter of 70 nm), the exposure amount was changed stepwise to perform exposure. Note that ultrapure water was used as the immersion medium. Note that 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 the obtained resist pattern, an exposure amount at which the hole diameter of the pattern formed with a mask having a hole diameter of 70 nm was 55 nm was defined as effective sensitivity.

<Focus margin (DOF) evaluation>
In terms of effective sensitivity, the focus range in which the hole diameter of the resist pattern formed using the mask is 52.2 nm to 57.7 nm is defined as DOF. That is, the DOF is
If it is 0.18 μm or more, “○”,
What was less than 0.18 micrometer was made into "x".
The results are shown in Table 2. Numerical values in parentheses indicate DOF values (μm).

<Defect evaluation>
The resist composition was applied (spin coated) to a 12-inch silicon wafer (substrate) so that the film thickness after drying was 0.15 μm. After coating, the composition layer was formed on the wafer by pre-baking (PB) for 60 seconds on the direct hot plate at the temperature shown in the PB column of Table 1.
The wafer on which the composition layer was formed in this manner was subjected to water rinsing for 60 seconds using a developing machine [ACT-12; manufactured by Tokyo Electron Ltd.].
Thereafter, the number of defects on the wafer was measured using a defect inspection apparatus [KLA-2360; manufactured by KLA Tencor].
The results are shown in Table 2.

  According to the resist composition of the present invention, it is possible to obtain a resist pattern having a good focus margin (DOF) at the time of producing the resist pattern and few defects.

Claims (8)

(A1) a resin having a structural unit represented by formula (I),
(A2) Resin composition having a structural unit represented by formula (II), insoluble or hardly soluble in an alkaline aqueous solution, and soluble in an alkaline aqueous solution by the action of an acid, and (B) an acid generator object.

[In the formula (I),
R ³ represents a hydrogen atom or a methyl group.
A ¹ _{is, - (CH 2) m1 -} , - (CH 2) m2 -O- (CH 2) m3 - or _{- (CH 2) m4 -CO-} O- (CH 2) m5 - represents a.
m1 to m5 each independently represents an integer of 1 to 6.
R ² represents a C 1-10 hydrocarbon group having a fluorine atom. ]

[In the formula (II),
Ring T ¹ represents a C3-C34 sultone ring which may have a substituent.
Z ¹ represents a C 1-17 saturated hydrocarbon group which may have a substituent, and —CH ₂ — contained in the saturated hydrocarbon group is —CO—, —O— or —N. (R ^c )-may be substituted. However, —CH ₂ — which is a bonding position to —CO— in T ¹ —O—CO— is not replaced by —N (R ^c ).
R ^c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
R ¹ represents a C 1-6 alkyl group, a hydrogen atom or a halogen atom which may have a halogen atom. ] The resist composition according to claim 1, wherein R ² is a fluorinated alkyl group having 1 to 6 carbon atoms. The resist composition according to claim 1, wherein A ¹ is a methylene group. The resist composition according to claim 1, wherein the ring T ¹ is a polycyclic sultone ring. The resist composition according to claim 1, wherein the ring T ¹ is a ring represented by the formula (T1).

[In the formula (T1),
R ⁴ is a C 1-12 alkyl group optionally having a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, an oxy group, a cyano group, a C 1-12 alkoxy group, a C 6-12 12 represents an aryl group having 12 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an acyl group having 2 to 4 carbon atoms.
m represents an integer of 0 to 9. When m is 2 or more, the plurality of R ⁴ are the same or different.
* Represents a bond with an oxygen atom. ] Z ¹ is —NH— (CH ₂ ) _n1 — * or —NH— (CH ₂ ) _n1 —COO— (CH ₂ ) _n2 — * (n1 and n2 each independently represents an integer of 1 to 6) , * Represents a bond of T ¹ —O—CO—.) The resist composition according to claim 1.   Furthermore, the resist composition in any one of Claims 1-6 containing a solvent. (1) The process of apply | coating the resist composition in any one of Claims 1-7 on a board | substrate,
(2) The process of drying the composition after application | coating and forming a composition layer,
(3) a step of exposing the composition layer,
(4) a step of heating the composition layer after exposure, and (5) a step of developing the composition layer after heating,
A method for producing a resist pattern including: