JP6182864B2 - Method for producing resist pattern - Google Patents

Description

  The present invention relates to a resist pattern manufacturing method.

In semiconductor manufacturing with higher integration, development of far-ultraviolet lithography technology using an ArF excimer laser or the like as an exposure source is being actively conducted. As a method for producing a resist pattern used in such deep ultraviolet lithography technology, for example,
(A) A resist composition for negative development, which contains a resin whose polarity is increased by the action of an acid, and which increases its solubility in a positive developer and decreases its solubility in a negative developer by irradiation with actinic rays or radiation. Applying an object and forming a resist film having a receding contact angle with respect to water of 70 degrees or more,
(A) a step of exposing through an immersion medium, and (c) a step of developing using a negative developer,
Patent Document 1 discloses a pattern forming method including the above.

JP 2008-309879 A

However, in the above resist pattern manufacturing method, the technical level of line edge roughness (LER) is not sufficiently satisfactory.

［式（Ｉ）中、
Ｒ^３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。
環Ｘ^１は、炭素数２〜３６の複素環を表し、該複素環に含まれる水素原子は、ハロゲン原子、ヒドロキシ基、炭素数１〜２４の炭化水素基、炭素数１〜１２のアルコキシ基、炭素数２〜４のアシル基又は炭素数２〜４のアシルオキシ基で置換されていてもよい。］
〔２〕前記ネガ型現像液は、酢酸ブチル及び２−ヘプタノンからなる群より選ばれる少なくとも一種を含む現像液である〔１〕記載の製造方法。
〔３〕前記工程（５）は、ダイナミックディスペンス法により現像する工程である〔１〕又は〔２〕記載の製造方法。
〔４〕前記樹脂（Ａ１）は、酸の作用により分解し、酢酸ブチル及び２−ヘプタノンのうち少なくとも一種への溶解性が減少する樹脂である〔１〕〜〔３〕のいずれか一つに記載の製造方法。
〔５〕前記樹脂（Ａ２）は、式(ａ４−１)で表される構造単位からなる樹脂である〔１〕〜〔４〕のいずれか１つに記載の製造方法。

［式（ａ４−１）中、
Ｒ^a41は、炭素数１〜１２の１価の炭化水素基を表し、該炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
Ａ^a41は、置換基を有していてもよい炭素数１〜６のアルカンジイル基又は式（ａ−ｇ１）

（式（ａ−ｇ１）中、ｓは０又は１を表す。
Ａ^a42及びＡ^a44は、それぞれ独立に、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基を表す。
Ａ^a43は、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基又は単結合を表す。
Ｘ^a41及びＸ^a42は、それぞれ独立に、酸素原子、カルボニル基、カルボニルオキシ基又はオキシカルボニル基を表す。
ただし、Ａ^a42、Ａ^a43、Ａ^a44、Ｘ^a41及びＸ^a42の炭素数の合計は７以下である。）
で表される基を表す。
Ｒ^a42は、置換基を有していてもよい炭素数１〜２０の炭化水素基であって、そのメチレン基がカルボニルオキシ基又はオキシカルボニル基で置換されてもよい炭化水素基を表わす。
ただし、Ａ^a41及びＲ^a４２のうち少なくとも一方は、フッ素原子を有する基である。］
〔６〕前記樹脂（Ａ２）は、脂環式炭化水素基を含む構造単位を更に有する樹脂である〔５〕記載の製造方法。
〔７〕前記樹脂（Ａ２）の含有量が、前記樹脂（Ａ１）１００質量部に対して、１〜６０質量部である〔１〕〜〔６〕のいずれか一つに記載の製造方法。
〔８〕前記酸発生剤は、式（Ｂ１）で表される酸発生剤である〔１〕〜〔７〕のいずれか一つに記載の製造方法。

［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、炭素数１〜２４の脂肪族飽和炭化水素基を表し、該脂肪族飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基に置き換わっていてもよく、該脂肪族飽和炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
Ｙは、水素原子、フッ素原子又は置換基を有していてもよい炭素数３〜２４の脂環式炭化水素基を表し、該脂環式炭化水素基を構成するメチレン基は、酸素原子、スルホニル基又はカルボニル基に置き換わっていてもよい。
Ｚ⁺は、有機カチオンを表す。］ The present invention includes the following inventions.
[1] (1) Resin (A1) having a structural unit represented by formula (I) and a structural unit having an acid labile group,
A resin (A2) having a fluorine atom and soluble in a negative developer,
Applying a resist composition containing an acid generator and a solvent on a substrate;
(2) A step of drying the resist composition after coating to form a composition layer;
(3) exposing the composition layer;
(4) A step of heating the composition layer after exposure;
(5) A method for producing a resist pattern, comprising a step of developing the heated composition layer with a negative developer.

[In the formula (I),
R ³ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
Ring ^{X 1} represents a heterocycle having 2 to 36 carbon atoms, a hydrogen atom contained in the heterocyclic ring, halogen atom, hydroxy group, a hydrocarbon group having 1 to 24 carbon atoms, an alkoxy group having 1 to 12 carbon atoms , May be substituted with an acyl group having 2 to 4 carbon atoms or an acyloxy group having 2 to 4 carbon atoms. ]
[2] The production method according to [1], wherein the negative developer is a developer containing at least one selected from the group consisting of butyl acetate and 2-heptanone.
[3] The production method according to [1] or [2], wherein the step (5) is a step of developing by a dynamic dispensing method.
[4] The resin (A1) is a resin that is decomposed by the action of an acid and has reduced solubility in at least one of butyl acetate and 2-heptanone. The manufacturing method as described.
[5] The production method according to any one of [1] to [4], wherein the resin (A2) is a resin including a structural unit represented by the formula (a4-1).

[In the formula (a4-1),
R ^a41 represents a monovalent hydrocarbon group having 1 to 12 carbon atoms, and the methylene group constituting the hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
A ^a41 is an alkanediyl group having 1 to 6 carbon atoms which may have a substituent or a formula (a-g1).

(In the formula (a-g1), s represents 0 or 1.
A ^a42 and A ^a44 each independently represent an ^optionally substituted aliphatic hydrocarbon group having 1 to 5 carbon atoms.
A ^a43 represents an aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent or a single bond.
X ^a41 and X ^a42 each independently represent an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group.
However, the total number of carbon atoms of A ^a42 , A ^a43 , A ^a44 , X ^a41 and X ^a42 is 7 or less. )
Represents a group represented by
R ^a42 represents a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and the methylene group may be substituted with a carbonyloxy group or an oxycarbonyl group.
However, at least one of A ^a41 and R ^a42 is a group having a fluorine atom. ]
[6] The production method according to [5], wherein the resin (A2) is a resin further having a structural unit containing an alicyclic hydrocarbon group.
[7] The production method according to any one of [1] to [6], wherein the content of the resin (A2) is 1 to 60 parts by mass with respect to 100 parts by mass of the resin (A1).
[8] The production method according to any one of [1] to [7], wherein the acid generator is an acid generator represented by the formula (B1).

[In the formula (B1),
Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents an aliphatic saturated hydrocarbon group having 1 to 24 carbon atoms, and the hydrogen atom contained in the aliphatic saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group, and the aliphatic saturated carbon group The methylene group constituting the hydrogen group may be replaced with an oxygen atom or a carbonyl group.
Y represents a hydrogen atom, a fluorine atom or an optionally substituted alicyclic hydrocarbon group having 3 to 24 carbon atoms, and the methylene group constituting the alicyclic hydrocarbon group is an oxygen atom, A sulfonyl group or a carbonyl group may be substituted.
Z ⁺ represents an organic cation. ]

［式中、
Ｒ^３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。
環Ｘ^１は、炭素数２〜３６の複素環を表し、該複素環に含まれる水素原子は、ハロゲン原子、ヒドロキシ基、炭素数１〜２４の炭化水素基、炭素数１〜１２のアルコキシ基、炭素数２〜４のアシル基又は炭素数２〜４のアシルオキシ基で置換されていてもよい。］
で表される構造単位と酸不安定基を有する構造単位とを有する樹脂（Ａ１）、
フッ素原子を有し、かつネガ型現像液に溶解する樹脂（Ａ２）、
酸発生剤及び
溶剤を含有するネガ型現像用レジスト組成物。 [9] The production method according to [8], wherein Y is an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent.
[10] Formula (I)

[Where:
R ³ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
Ring ^{X 1} represents a heterocycle having 2 to 36 carbon atoms, a hydrogen atom contained in the heterocyclic ring, halogen atom, hydroxy group, a hydrocarbon group having 1 to 24 carbon atoms, an alkoxy group having 1 to 12 carbon atoms , May be substituted with an acyl group having 2 to 4 carbon atoms or an acyloxy group having 2 to 4 carbon atoms. ]
A resin (A1) having a structural unit represented by: and a structural unit having an acid labile group,
A resin (A2) having a fluorine atom and soluble in a negative developer,
A resist composition for negative development containing an acid generator and a solvent.

  According to the manufacturing method of the present invention, a resist pattern having a small line edge roughness (LER) can be obtained.

In the present specification, "(meth) acrylic monomer" means at least one monomer having a "CH ₂ = CH-CO-" or _{"CH 2 = C (CH 3)} -CO- " structure of To do. Similarly, “(meth) acrylate” and “(meth) acrylic acid” mean “at least one of acrylate and methacrylate” and “at least one of acrylic acid and methacrylic acid”, respectively.

The method for producing a resist pattern of the present invention comprises:
(1) A step of applying a resist composition on a substrate (hereinafter sometimes referred to as “step (1)”);
(2) A step of drying the resist composition after coating to form a composition layer (hereinafter sometimes referred to as “step (2)”);
(3) a step of exposing the composition layer (hereinafter referred to as “step (3)” in some cases);
(4) A step of heating the composition layer after exposure (hereinafter, referred to as “step (4)” in some cases);
(5) A step of developing the heated composition layer with a negative developer (hereinafter, sometimes referred to as “step (5)”);
including.

In the step (1), the substrate is not particularly limited, and examples thereof include inorganic substrates usually used for semiconductor production, such as silicon, SiN, SiO ₂ , SOG and the like. These substrates may be cleaned, or may be those in which an antireflection film or the like is formed on an inorganic substrate. The antireflection film can be formed from, for example, a commercially available composition for organic antireflection films.
Application of the resist composition onto the substrate can be performed by a coating apparatus widely used in the resist field, such as a spin coater.
The resist composition used in step (1) will be described later.

In the step (2), for example, a resist composition applied on the substrate by a heating means (so-called pre-bake) using a heating device such as a hot plate, a decompression means using a decompression device, or a combination of these means. The composition is dried by removing the solvent to form a composition layer. Preferably, it is drying by a heating means. The conditions for the heating means and the decompression means can be selected according to the type of the solvent (D) contained in the resist composition.
In the case of a heating means, the drying temperature is preferably 50 to 200 ° C, more preferably 60 to 150 ° C. The drying time is preferably 10 to 180 seconds, more preferably 30 to 120 seconds.
In the case of the decompression means, the resist composition applied on the substrate is sealed in a decompression dryer, and then dried at an internal pressure of 1 to 1.0 × 10 ⁵ Pa.
The film thickness of the composition layer thus formed is generally 20 to 1000 nm, preferably 50 to 400 nm. The film thickness can be adjusted by variously adjusting the conditions of the coating apparatus.

In step (3), the composition layer is preferably exposed using an exposure machine. The exposure is performed through a mask (photomask) on which a desired pattern is formed. As an exposure light source for an exposure machine, an apparatus that emits ultraviolet light such as a KrF excimer laser (wavelength 248 nm), an ArF excimer laser (wavelength 193 nm), an F ₂ excimer laser (wavelength 157 nm), an electron beam, or an ultra-ultraviolet light Various types are used such as those that irradiate (EUV), those that emit laser light from a solid-state laser light source (such as YAG or a semiconductor laser) and radiate far-wave or vacuum ultraviolet harmonic laser light. be able to. When an electron beam is used as the exposure light source, the composition layer may be directly irradiated and drawn without using a mask. As the exposure light source used in the production method of the present invention, an ArF excimer laser is preferable.
As a result of exposure through the mask, acid is generated from the acid generator (B) contained in the composition layer in the composition layer of the exposed portion. By the action of this acid, a hydrophilic group is formed from the acid labile group of the resin (A1).

The exposure is preferably performed by a method in which the immersion medium is placed on the composition layer, so-called immersion exposure. When performing immersion exposure, you may perform the process of wash | cleaning the surface of the composition layer before exposure and / or after exposure with an aqueous chemical | medical solution.
The immersion medium used for the immersion exposure is transparent to the exposure wavelength of the ArF excimer laser, and can have a temperature coefficient of refractive index so as to minimize distortion of the optical image projected onto the composition layer. A liquid that is as small as possible is preferable, and water, particularly ultrapure water, is preferable because it is easily available and easy to handle. When water is used as the immersion medium, an additive that decreases the surface tension of the water and increases the surface activity may be added to the water in a small proportion. This additive is preferably one that does not dissolve the composition layer and can ignore the influence on the optical coating on the lower surface of the lens element.
The exposure amount can be appropriately set according to the resist composition to be used, the type of resist pattern to be produced, and the type of exposure light source, and is preferably 5 to 50 mJ / cm ² .
Step (3) may be repeated a plurality of times. The exposure light source and the exposure method when performing multiple exposures may be the same or different.

The heating in the step (4) includes a heating means using a heating device such as a hot plate. The heating temperature is preferably 50 to 200 ° C, more preferably 70 to 150 ° C. The heating time is preferably 10 to 180 seconds, more preferably 30 to 120 seconds.
The reaction of the acid labile group is promoted by the step (4).

Step (5) is a step of developing the heated composition layer with a negative developer. That is, negative development of the composition layer after heating is performed in the step (5).
In step (5), development is preferably performed using a developing device.

The negative developer means a solvent that dissolves the unexposed composition layer and is insoluble or hardly soluble in the exposed composition layer.
The negative developer is preferably an organic solvent. Examples of the organic solvent include polar solvents such as ketone solvents, ester solvents, amide solvents, and ether solvents, and hydrocarbon solvents.
Examples of the ketone solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, 4-heptanone, 2-hexanone, diisobutylketone, cyclohexanone, methylcyclohexanone, phenylacetone, and methylisobutylketone.
As ester solvents, butyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, Examples include 3-methyl-3-methoxybutyl acetate, butyl formate, propyl formate, ethyl lactate, butyl lactate, and propyl lactate.
Examples of the ether solvent include ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, and triethylene glycol monoethyl ether.
Examples of the amide solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide and the like.
Examples of the hydrocarbon solvent include aromatic hydrocarbon solvents such as toluene and xylene, and aliphatic hydrocarbon solvents such as octane and decane.
Among the above organic solvents, the negative developer preferably contains an organic solvent selected from the group consisting of ketone solvents, ester solvents and ether solvents, and is selected from the group consisting of ketone solvents and ester solvents. It is more preferable that butyl acetate or 2-heptanone is included.
The negative developer preferably contains at least one selected from the group consisting of butyl acetate and 2-heptanone, that is, butyl acetate or 2-heptanone.
The developer may contain a solvent other than butyl acetate and 2-heptanone. Examples of such solvents include ketone solvents such as 2-hexanone; ester solvents such as propylene glycol monomethyl ether acetate; amide solvents such as N, N-dimethylacetamide; ether solvents such as propylene glycol monomethyl ether and glycol ether. A polar solvent, or a hydrocarbon solvent such as anisole. If it is slight, it may contain water.
The total content of butyl acetate and 2-heptanone is preferably 50% by mass or more based on the total amount of the developer, and is substantially at least one selected from the group consisting of butyl acetate and 2-heptanone. preferable. Further, it is more preferable that the developer is substantially only butyl acetate or substantially only 2-heptanone. As these developing solutions, those commercially available as solvents may be used as they are.

  The developer may contain a surfactant as necessary. The surfactant is not particularly limited, and may be an ionic surfactant or a nonionic surfactant, and a fluorosurfactant or a silicon surfactant may be used.

As a developing method, the composition layer after step (4) is immersed in a tank filled with a developer for a certain period of time together with the substrate (dip method), and the composition layer after step (4) is developed. A method in which the liquid is raised by surface tension and developed by standing for a certain time (paddle method), a method in which the developer is sprayed on the surface of the composition layer after step (4) (spray method), and a composition after step (4) Examples include a method (dynamic dispensing method) in which the substrate on which the physical layer is formed is rotated at a constant speed, and the developer is continuously applied while scanning the application nozzle at a constant speed.
Among these, as a developing method, a paddle method or a dynamic dispensing method is preferable, and a dynamic dispensing method is more preferable.
The development temperature is preferably 5 to 60 ° C, more preferably 10 to 40 ° C. The development time is preferably 5 to 300 seconds, and more preferably 5 to 90 seconds. When developing with the dynamic dispensing method, the developing time is particularly preferably 5 to 20 seconds, and when developing with the paddle method, the developing time is particularly preferably 20 to 60 seconds.
The exposed portion of the composition layer becomes insoluble or hardly soluble in the developer due to the reaction of the acid labile group described above. Therefore, when the composition layer is brought into contact with the developer, the unexposed portion of the composition layer is removed by the developer. Thus, a negative resist pattern is manufactured.

  After the development time has elapsed, the development may be stopped while replacing the developer in contact with the composition layer with a solvent of a different type from the developer. In addition, in order to remove the developer remaining on the resist pattern, it is preferable to wash the developed resist pattern using a rinse solution. The rinsing liquid is not particularly limited as long as it does not dissolve the produced resist pattern, and a general organic solvent can be used, but an alcohol solvent or an ester solvent is preferably used, and hexanol, pen C1-C8 monohydric alcohols such as butanol and butanol are more preferred.

Hereinafter, the resist composition used in step (1) will be described.
The resist composition is
Resin (A1) having a structural unit represented by the following formula (I) and a structural unit having an acid labile group, a resin (A2) having a fluorine atom and soluble in a negative developer, an acid generator And a negative resist composition containing a solvent.
The negative developing resist composition is also one aspect of the present invention.
<Resin (A1)>
Resin (A1) is
A structural unit represented by the formula (I) (hereinafter sometimes referred to as “structural unit (I)”);
And a structural unit having an acid labile group (hereinafter sometimes referred to as “structural unit (II)”).
The resin (A1) is preferably decomposed by the action of an acid and its solubility in a negative developer is reduced. When the developer contains at least one of butyl acetate and 2-heptanone, the resin (A1) is decomposed by the action of an acid. More preferably, the solubility in at least one of butyl acetate and 2-heptanone is reduced.
Examples of the acid in the above “action of acid” include acids generated from an acid generator. When the resin (A1) is decomposed by the action of an acid, the acid labile group of the structural unit (II) is usually converted to a hydrophilic group.

［式（Ｉ）中、
Ｒ^３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。
環Ｘ^１は、炭素数２〜３６の複素環を表し、該複素環に含まれる水素原子は、ハロゲン原子、ヒドロキシ基、炭素数１〜２４の炭化水素基、炭素数１〜１２のアルコキシ基、炭素数２〜４のアシル基又は炭素数２〜４のアシルオキシ基で置換されていてもよい。］ <Structural unit represented by formula (I)>

[In the formula (I),
R ³ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
Ring ^{X 1} represents a heterocycle having 2 to 36 carbon atoms, a hydrogen atom contained in the heterocyclic ring, halogen atom, hydroxy group, a hydrocarbon group having 1 to 24 carbon atoms, an alkoxy group having 1 to 12 carbon atoms , May be substituted with an acyl group having 2 to 4 carbon atoms or an acyloxy 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 represented by R ³ 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 represented by R ³ 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 a perfluorohexyl group.
R ³ is preferably a methyl group or a hydrogen atom.

Ring X ¹ includes a nitrogen atom and a carbon atom of a carbonyl group (—CO—) as atoms constituting the ring, and includes a hetero atom other than the nitrogen atom as an atom constituting the ring. Also good. Ring X ¹ may be an aromatic heterocycle or a heterocycle having no aromaticity, and may be monocyclic or polycyclic.

芳香族炭化水素基としては、例えば、フェニル基、ナフチル基、アントリル基、ビフェニリル基、フェナントリル基及びフルオレニル基等が挙げられる。
アルコキシ基としては、メトキシ基、エトキシ基、プロポキシ基、ブトキシ基、ペンチルオキシ基、ヘキシルオキシ基、ヘプチルオキシ基、オクチルオキシ基、デシルオキシ基及びドデシルオキシ基等が挙げられる。
アシル基としては、アセチル基、プロピオニル基及びブチリル基等が挙げられる。
アシルオキシ基としては、アセチルオキシ基、プロピオニルオキシ基、ブチリルオキシ基及びイソブチリルオキシ基等が挙げられる。 Among the substituents of the ring X ^1, examples of the hydrocarbon group include chain and cyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and groups in which these are combined. Examples of chain aliphatic hydrocarbon groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl, hexadecyl, pentadecyl, hexyldecyl , Heptadecyl group and octadecyl group. Examples of the cyclic aliphatic hydrocarbon group (hereinafter, the cyclic aliphatic hydrocarbon group may be referred to as an alicyclic hydrocarbon group) include, for example, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, Examples thereof include cycloalkyl groups such as cyclooctyl group; polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl group, adamantyl group, norbornyl group and the following groups (* represents a bond).

Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthryl group, a biphenylyl group, a phenanthryl group, and a fluorenyl group.
Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy group.
Examples of the acyl group include an acetyl group, a propionyl group, and a butyryl group.
Examples of the acyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, and an isobutyryloxy group.

Ring X ¹ is preferably a 4- to 6-membered heterocyclic ring containing —CO— and a nitrogen atom, or a bridged ring containing such a ring structure. Examples of the bridged ring include a bicyclic heterocycle having a 4- to 6-membered ring containing —CO— and a nitrogen atom, and a tricyclic heterocycle having the 4- to 6-membered ring. Ring X ¹ is preferably a ring in which —CO— and a nitrogen atom contained in the heterocyclic ring form an amide bond, that is, a lactam ring.

Examples of the ring X ¹ include a ring represented by the following formula. In the following formula, * represents a bond with a carbonyl group.

［式（ＩＡ）中、
Ｒ²³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。
Ｒ²⁴、Ｒ^2５、Ｒ^2６、Ｒ^2７、Ｒ^2８及びＲ²⁹は、それぞれ独立に、水素原子又は炭素数１〜２４の炭化水素基を表すか、Ｒ²⁴、Ｒ^2５、Ｒ^2６、Ｒ^2７、Ｒ^2８及びＲ²⁹の中から選ばれる２つは、互いに結合して炭素数３〜３０の環を形成し、該炭化水素基に含まれる水素原子は、ハロゲン原子又はヒドロキシ基で置換されていてもよく、該環に含まれる水素原子は、ハロゲン原子、ヒドロキシ基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数２〜４のアシル基又は炭素数２〜４のアシルオキシ基に置換されていてもよく、該炭化水素基及び該環を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
ｎは、０〜３の整数を表す。］ The structural unit (I) is preferably a structural unit represented by the formula (IA).

[In the formula (IA),
R ²³ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
R ²⁴ , R ²⁵ , R ²⁶ , R ²⁷ , R ²⁸ and R ²⁹ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 24 carbon atoms, or R ²⁴ , R ²⁵ , R ²⁶ , R ^27. , R ²⁸ and R ²⁹ are bonded to each other to form a ring having 3 to 30 carbon atoms, and the hydrogen atom contained in the hydrocarbon group is substituted with a halogen atom or a hydroxy group The hydrogen atom contained in the ring may be a halogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an acyl group having 2 to 4 carbon atoms, or 2 to 2 carbon atoms. 4 may be substituted with an acyloxy group, and the hydrocarbon group and the methylene group constituting the ring may be replaced with an oxygen atom or a carbonyl group.
n represents an integer of 0 to 3. ]

［式（ＩＢ）中、
Ｒ³¹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。
ｎ３は、０〜８の整数を表す。
Ｒ³²は、ハロゲン原子、ヒドロキシ基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数２〜４のアシル基又は炭素数２〜４のアシルオキシ基を表す。
ｎ３が２以上のとき、複数のＲ³²は同一又は互いに相異なる。］ The structural unit represented by the formula (IA) is preferably a structural unit represented by the formula (IB) or the formula (IC), and more preferably a structural unit represented by the formula (IB).

[In the formula (IB),
R ³¹ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
n3 represents an integer of 0 to 8.
R ³² represents a halogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an acyl group having 2 to 4 carbon atoms, or an acyloxy group having 2 to 4 carbon atoms.
When n3 is 2 or more, the plurality of R ³² are the same or different from each other. ]

R ³¹ in the formula (IB) includes the same groups as R ³ in the formula (I), and is preferably a hydrogen atom or a methyl group.
R ³² is preferably a fluorine atom, a hydroxy group, an acetyl group, a methyl group or an ethyl group.
n3 is preferably 0 or 1, more preferably 0.

［式（ＩＣ）中、
Ｒ⁴¹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。
ｎ４は、０〜１４の整数を表す。
Ｒ⁴²は、ハロゲン原子、ヒドロキシ基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数２〜４のアシル基又は炭素数２〜４のアシルオキシ基を表す。
ｎ４が２以上のとき、複数のＲ^４2は同一又は互いに相異なる。］

[In the formula (IC)
R ⁴¹ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
n4 represents the integer of 0-14.
^R42 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an acyl group having 2 to 4 carbon atoms, or an acyloxy group having 2 to 4 carbon atoms.
When n4 is 2 or more, the plurality of R ⁴² are the same or different from each other. ]

Examples of R ⁴¹ in the formula (IC) include the same groups as R ³ in the formula (I), and preferably a hydrogen atom or a methyl group.
R ⁴² is preferably a fluorine atom, a hydroxy group, an acetyl group, a methyl group or an ethyl group.
n4 is preferably 0 or 1, more preferably 0.

Specific examples of the structural unit (I) are shown below.

これらの具体例において、Ｒ^３に相当するメチル基が水素原子に置き換わったものも、構造単位（Ｉ）の具体例として挙げることができる。

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

［式（Ｉ’）中、環Ｘ^１及びＲ^３は何れも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 the formula (I ′), each of the rings X ¹ and R ³ represents the same meaning as described above. ]

［式中、環Ｘ^１及びＲ^３は、上記と同じ意味を表す。
Ｘは、ハロゲン原子又は（メタ）アクリロイルオキシ基を表す。］
ハロゲン原子としては、塩素原子、臭素原子及びヨウ素原子が好ましく、塩素原子がより好ましい。 Although the manufacturing method of compound (I ') is not specifically limited, Compound (I') includes, for example, a compound represented by formula (Ia) and a compound represented by formula (Ib), It can manufacture by making it react in a solvent in presence of a catalyst. As the catalyst, N-methylpyrrolidine is preferable. Moreover, as a solvent used for this reaction, dimethylformamide is preferable.

[Wherein, ring X ¹ and R ³ represent the same meaning as described above.
X represents a halogen atom or a (meth) acryloyloxy group. ]
As a halogen atom, a chlorine atom, a bromine atom, and an iodine atom are preferable, and a chlorine atom is more preferable.

Examples of the compound represented by the formula (Ia) include the following compounds. These compounds may be commercially available products or those produced by a known production method.

式（Ｉ−ｂ）で表される化合物としては、メタクリル酸クロライド及びメタクリル酸無水物等が挙げられる。 Among the compounds represented by the formula (Ia), the compound represented by the formula (Ia-1) capable of deriving the structural unit represented by the formula (IB) includes cyclopentene and chlorosulfonyl isocyanate. (See JP-T-2007-514775).

Examples of the compound represented by the formula (Ib) include methacrylic acid chloride and methacrylic anhydride.

  The content of the structural unit (I) is preferably from 1 to 80 mol%, more preferably from 2 to 75 mol%, more preferably from 3 to 70 mol%, based on all the structural units of the resin (A1). 65 mol% is still more preferable, and 5-55 mol% is especially preferable.

［式（１）中、
Ｒ^a1、Ｒ^ａ２及び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１価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する。該１価の炭化水素基及び該２価の炭化水素基を構成するメチレン基は、酸素原子又は硫黄原子に置き換わってもよい。＊は結合手を表す。］ <Structural unit having acid labile group (Structural unit (II))>
The “acid labile group” means a group having a leaving group and forming a hydrophilic group (for example, a hydroxy group or a carboxy group) by leaving the leaving group by contact with an acid. Examples of the acid labile group include a group represented by the formula (1) and a group represented by the formula (2).

[In Formula (1),
R ^a1 , R ^a2 and R ^a3 each independently represent an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or R ^a1 and R ^a2 are bonded to each other to form carbon A divalent hydrocarbon group of 2 to 20 is formed. * Represents a bond. ]

[In Formula (2),
R ^{a1 ′} and R ^{a2 ′} each independently represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms, and R ^{a3 ′} represents a hydrocarbon group having 1 to 20 carbon atoms, or R ^{a3 ′ a2 ′} and R ^{a3 ′} combine with each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms. The monovalent hydrocarbon group and the methylene group constituting the divalent hydrocarbon group may be replaced with an oxygen atom or a sulfur atom. * Represents a bond. ]

Ｒ^a1、Ｒ^ａ２及びＲ^a3で表わされる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 , R ^a2 and 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.
Examples of the alicyclic hydrocarbon group represented by R ^a1 , R ^a2 and R ^a3 include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents a bond).

The alicyclic hydrocarbon group represented by R ^a1 , R ^a2 and R ^a3 preferably has 3 to 16 carbon atoms.

Examples of the group represented by —C (R ^a1 ) (R ^a2 ) (R ^a3 ) when R ^a1 and R ^a2 are bonded to each other to form a divalent hydrocarbon group include the following groups. It is done. The divalent hydrocarbon group preferably has 3 to 12 carbon atoms. * Represents a bond to —O—, and R ^a3 represents an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group represented by 3 to 20 carbon atoms.

Examples of the group represented by the formula (1) include a 1,1-dialkylalkoxycarbonyl group (in the formula (1), R ^a1 , R ^a2 and R ^a3 are alkyl groups, preferably a tert-butyl group), 2-alkyladamantan-2-yloxycarbonyl group (in the formula (1), R ^a1 and R ^a2 are bonded to form an adamantyl ring 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 represented by R ^{a1 ′} and R ^{a2 ′} 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. Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthryl group, a biphenylyl group, a phenanthryl group, and a fluorenyl group.
Examples of the divalent hydrocarbon group R ^{a2 'and} R ^a3' is formed by bonding with, R ^{a1 ',} R ^a2' include one obtained by removing groups a hydrogen atom from a hydrocarbon group and R ^{a3 '} .
At least one of R ^{a1 ′} and R ^{a2 ′} is preferably a hydrogen atom.

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

  The structural unit (II) is derived from a monomer having an acid labile group (hereinafter sometimes referred to as “monomer (a1)”). The monomer (a1) is preferably one having an acid labile group and a carbon-carbon double bond from the viewpoint that the resin (A1) can be easily produced, and more preferably a (meth) acrylic monomer having an acid labile group. preferable.

  Among the monomers (a1), the monomer (a1) having a group represented by the formula (1) and / or a group represented by the formula (2) is preferable, and a group represented by the formula (1) and / or Or the (meth) acrylic-type monomer which has group represented by Formula (2) is more preferable.

  The monomer (a1) is preferably a monomer (a1) having an alicyclic hydrocarbon group having 5 to 20 carbon atoms. From the resist composition containing the resin (A1) obtained using the monomer (a1) having such a bulky structure, a resist pattern having a better resolution tends to be obtained.

［式（ａ１−１）及び式（ａ１−２）中、
Ｌ^a1及びＬ^a2は、それぞれ独立に、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k1−ＣＯ−Ｏ−で表される基を表し、ｋ１は１〜７の整数を表し、＊はカルボニル基との結合手を表す。
Ｒ^a4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。］ As the structural unit (II), a structural unit represented by the formula (a1-1) (hereinafter sometimes referred to as “structural unit (a1-1)”) and a structural unit represented by the formula (a1-2) (Hereinafter, it is sometimes referred to as “structural unit (a1-2)”). Resin (A1) may have these individually or in multiple types.

[In Formula (a1-1) and Formula (a1-2),
L ^a1 and L ^a2 each independently represent an oxygen atom or a group represented by ^* —O— (CH ₂ ) _k1 —CO—O—, k1 represents an integer of 1 to 7, and * represents a carbonyl group Represents a bond with
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. ]

L ^a1 and L ^a2 are preferably an oxygen atom or a group represented by * —O— (CH ₂ ) _k1 —CO—O—, wherein k1 is an integer of 1 to 4, more preferably an oxygen atom. or * -O-CH ₂ -CO-O- and, still more preferably an oxygen atom.
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, an octyl group, and the like, preferably an alkyl group having 1 to 6 carbon atoms. is there.
Examples of the alicyclic hydrocarbon group represented by R ^a6 and R ^a7 include the same groups as those described for R ^a1 , R ^a2 and R ^a3 in formula (1), preferably 3 to 8 carbon atoms, More preferably, it is a C3-C6 alicyclic hydrocarbon group.
m1 is preferably an integer of 0 to 3, more preferably 0 or 1.
n1 is preferably an integer of 0 to 3, more preferably 0 or 1.
n1 ′ is preferably 0 or 1.

As the structural unit (a1-1), for example, a formula (a1-1-1), a formula (a1-1-2), a formula (a1-1-3), a formula (a1-1-4), a formula ( and a structural unit represented by any one of formula (a1-1-5), formula (a1-1-6), formula (a1-1-7), and formula (a1-1-8). 1-1), the structural unit represented by any one of formula (a1-1-2), formula (a1-1-3) and formula (a1-1-4) is preferable.

  Examples of the monomer capable of deriving the structural unit (a1-1) include those described in JP-A No. 2010-204646.

As the structural unit (a1-2), for example, a formula (a1-2-1), a formula (a1-2-2), a formula (a1-2-3), a formula (a1-2-4), a formula ( a 1-2-5) or a structural unit represented by the formula (a1-2-6). Among these, the structural unit represented by any one of formulas (a1-2-3) and (a1-2-4) is preferable, and the structural unit represented by formula (a1-2-3) is more preferable. .

  As monomers for deriving the structural unit (a1-2), 1-ethylcyclopentan-1-yl (meth) acrylate, 1-ethylcyclohexane-1-yl (meth) acrylate, 1-ethylcycloheptan-1-yl (Meth) acrylate, 1-methylcyclopentan-1-yl (meth) acrylate, 1-isopropylcyclopentan-1-yl (meth) acrylate and the like.

When resin (A1) has a structural unit (a1-1) and / or a structural unit (a1-2), these total content rates are 10-99 normally with respect to all the structural units of resin (A1). Mol% (, preferably 15 to 99 mol%, more preferably 20 to 95 mol%, still more preferably 20 to 85 mol%, particularly preferably 20 to 60 mol%.
The resin (A1) preferably has a structural unit (II) having an adamantyl group, more preferably a structural unit (a1-1) as the structural unit (II). In this case, the content of the structural unit (II) having an adamantyl group is preferably 15 mol% or more with respect to the total content of the structural unit (II). A resist pattern manufactured from a resist composition containing such a resin (A1) tends to have good dry etching resistance.

  As the monomer for deriving the structural unit (II), in addition to the monomer deriving the structural unit (a1-1) and the monomer deriving the structural unit (a1-2), a monomer represented by the formula (a1-3), The monomer represented by the formula (a1-4) and the monomer represented by the formula (a1-5) (hereinafter, “monomer (a1-3)”, “monomer (a1-4)”, “monomer ( a1-5) ")).

［式（ａ１−３）中、
Ｒ^a9は、水素原子、置換基（例えばヒドロキシ基）を有していてもよい炭素数１〜３の脂肪族炭化水素基、カルボキシ基、シアノ基、又は−ＣＯＯＲ^a13で表される基を表し、Ｒ^a13は、炭素数１〜８の脂肪族炭化水素基を表し、該脂肪族炭化水素基に含まれる水素原子はヒドロキシ基等で置換されていてもよく、該脂肪族炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
Ｒ^a10、Ｒ^a11及びＲ^a12は、それぞれ独立に、炭素数１〜１２の脂肪族炭化水素基を表すか、或いはＲ^a10及びＲ^a11は互いに結合して、これらが結合する炭素原子とともに環を形成する。該脂肪族炭化水素基に含まれる水素原子はヒドロキシ基等で置換されていてもよく、該脂肪族炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。］ From the resist composition containing the resin (A1) having a structural unit derived from the monomer (a1-3), there is a tendency that a resist pattern excellent in dry etching resistance can be produced.

[In the formula (a1-3),
R ^a9 represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 3 carbon atoms which may have a substituent (for example, a hydroxy group), a carboxy group, a cyano group, or a group represented by —COOR ^a13. , R ^a13 represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms, and a hydrogen atom contained in the aliphatic hydrocarbon group may be substituted with a hydroxy group or the like, and constitutes the aliphatic hydrocarbon group The methylene group may be replaced by an oxygen atom or a carbonyl group.
R ^a10 , R ^a11 and R ^a12 each independently represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or R ^a10 and R ^a11 are bonded to each other to form a ring together with the carbon atom to which they are bonded. Form. A hydrogen atom contained in the aliphatic hydrocarbon group may be substituted with a hydroxy group or the like, and a methylene group constituting the aliphatic hydrocarbon group may be replaced with an oxygen atom or a carbonyl group. ]

Examples of the aliphatic hydrocarbon group represented by R ^a9 include an alkyl group, and specific examples include a methyl group, an ethyl group, and a propyl group. Examples of the substituent, particularly the aliphatic hydrocarbon group having a hydroxy group, include a hydroxymethyl group and a 2-hydroxyethyl group.
^Examples of the group represented by R ^a13 include a methyl group, an ethyl group, a propyl group, a 2-oxo-oxolan-3-yl group, and a 2-oxo-oxolan-4-yl group.

The aliphatic hydrocarbon group represented by R ^a10 , R ^a11 and R ^a12 is, for example, an alkyl group, and specific examples thereof are the same as those exemplified for R ^a1 , R ^a2 and R ^a3 in formula (1). . Examples of the ring formed together with the carbon atoms to which R ^a10 and R ^a11 are bonded to each other include a cyclohexane ring and an adamantane ring.

As a monomer (a1-3), what was described in Unexamined-Japanese-Patent No. 2010-204646 is used. Among these, a monomer represented by any one of formula (a1-3-1), formula (a1-3-2), formula (a1-3-3) and formula (a1-3-4) is preferable, A monomer represented by any one of formulas (a1-3-2) and (a1-3-4) is more preferred, and a monomer represented by formula (a1-3-2) is more preferred.

  When the resin (A1) has a structural unit derived from the monomer (a1-3), the content thereof is preferably 10 to 99 mol% with respect to all the structural units of the resin (A1), and 15 to 95 mol. % Is more preferable, and 20 to 85 mol% is more preferable.

［式（ａ１−４）中、
Ｒ¹⁰は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
ｌ^ａは０〜４の整数を表す。
Ｒ¹¹は、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数２〜４のアシル基、炭素数２〜４のアシルオキシ基、アクリロイル基又はメタクリロイル基を表し、ｌ^ａが２以上である場合、複数のＲ¹¹は互いに同一であっても異なってもよい。
Ｒ¹²及びＲ¹³はそれぞれ独立に、水素原子又は炭素数１〜１２の炭化水素基を表す。
Ｘ^a2は、置換基を有していてもよい炭素数１〜１７の脂肪族炭化水素基又は単結合を表し、該脂肪族炭化水素基を構成するメチレン基は、酸素原子、硫黄原子、カルボニル基、スルホニル基又は−Ｎ（Ｒ^ｃ）−（ただし、Ｒ^ｃは、水素原子又は炭素数１〜６のアルキル基を表す）で表される基に置き換わっていてもよい。
Ｙ^a3は、置換基を有していてもよい炭素数１〜１８の炭化水素基を表す。］ The monomer (a1-4) is represented by the formula (a1-4).

[In the formula (a1-4),
R ¹⁰ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
l ^a represents an integer of 0 to 4;
R ¹¹ is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an acryloyl group, or methacryloyl. In the case where l ^a is 2 or more, a plurality of R ¹¹ may be the same as or different from each other.
R ¹² and R ¹³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.
X ^a2 represents an ^optionally substituted aliphatic hydrocarbon group having 1 to 17 carbon atoms or a single bond, and the methylene group constituting the aliphatic hydrocarbon group includes an oxygen atom, a sulfur atom, a carbonyl A group, a sulfonyl group, or a group represented by —N (R ^c ) — (wherein R ^c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms) may be substituted.
Y ^a3 represents an ^optionally substituted hydrocarbon group having 1 to 18 carbon atoms. ]

Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R ¹⁰ include the same groups as R ³ in formula (I). Among them, R ¹⁰ is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and further preferably a hydrogen atom or a methyl group.
Examples of the alkoxy group represented by R ¹¹ include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, and a hexyloxy group. Among them, R ¹¹ is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and further preferably a methoxy group.
Examples of the acyl group represented by R ¹¹ include an acetyl group, a propionyl group, and a butyryl group.
Examples of the acyloxy group represented by R ¹¹ include an acetyloxy group, a propionyloxy group, a butyryloxy group, and an isobutyryloxy group.

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、ビフェニリル基、フェナントリル基及びフルオレニル基等が挙げられる。 Examples of the hydrocarbon group represented by R ¹² and R ¹³ include chain and cyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and groups in which these are combined. Examples of the chain aliphatic hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, and a dodecyl group. Examples of the cyclic aliphatic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, and a norbornyl group. Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and a biphenylyl group.
Examples of the hydrocarbon group represented by Y ^a3 include chain and cyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and groups in which these are combined. Examples of chain aliphatic hydrocarbon groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl, hexadecyl, pentadecyl, and hexyl. A decyl group, a heptadecyl group, an octadecyl group, etc. are mentioned. Examples of the cyclic aliphatic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents a bond).

Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthryl group, a biphenylyl group, a phenanthryl group, and a fluorenyl group.

Examples of the aliphatic hydrocarbon group represented by X ^a2 include a divalent chain hydrocarbon group, a divalent alicyclic hydrocarbon group, and a divalent group in which these are combined. Examples thereof include a group in which one hydrogen atom is removed from the alkyl group or the alicyclic hydrocarbon group of R ^{a1 to} R ^{a3 in} 1).

As a monomer (a1-4), the monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned, for example. Among them, formula (a1-4-1), formula (a1-4-2), formula (a1-4-3), formula (a1-4-4), formula (a1-4-5), formula (a1) -4-6) and a monomer represented by any one of formulas (a1-4-7) are preferred, and the formula (a1-4-1), formula (a1-4-2), and formula (a1-4-3) The monomer represented by any one of formula (a1-4-4) and formula (a1-4-5) is more preferred.

  When the resin (A1) has a structural unit derived from the monomer (a1-4), the content is preferably from 10 to 99 mol%, more preferably from 10 to 95 mol%, based on all the structural units of the resin (A1). Is more preferable, 15 to 95 mol% is more preferable, and 20 to 85 mol% is more preferable.

式（ａ１−５）中、
Ｒ^ａ31は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
Ｌ^ａ１、Ｌ^ａ２及びＬ^ａ３は、酸素原子、硫黄原子又は^＊−Ｏ−（ＣＨ₂）_k1−ＣＯ−Ｏ−で表される基を表す。ここで、ｋ１は１〜７の整数を表し、＊はカルボニル基との結合手を表す。
Ｚ^ａ１は、単結合又は炭素数１〜６のアルカンジイル基であり、該アルカンジイル基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
ｓ１及びｓ１’は、それぞれ独立に、０〜４の整数を表す。 A monomer (a1-5) is represented by a formula (a1-5).

In formula (a1-5),
R ^a31 represents a C 1-6 alkyl group which may have a halogen atom, a hydrogen atom or a halogen atom.
L ^a1 , L ^a2 and L ^a3 represent an oxygen atom, a sulfur atom or a group represented by ^* —O— (CH ₂ ) _k1 —CO—O—. Here, k1 represents an integer of 1 to 7, and * represents a bond with a carbonyl group.
Z ^a1 is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and the methylene group constituting the alkanediyl group may be replaced with an oxygen atom or a carbonyl group.
s1 and s1 ′ each independently represents an integer of 0 to 4.

R ^a31 in formula (a1-5) is preferably a hydrogen atom, a methyl group, or a trifluoromethyl group.
L ^a1 is preferably an oxygen atom.
One of L ^a2 and L ^a3 is preferably an oxygen atom and the other is a sulfur atom.
s1 is preferably 1.
s1 ′ is preferably an integer of 0 to 2.
Z ^a1 is preferably a single bond or —CH ₂ —CO—O—.

Examples of the monomer (a1-5) include the following monomers.

  When the resin (A1) has a structural unit derived from the monomer (a1-5), the content is preferably from 3 to 50 mol%, preferably from 5 to 40 mol, based on all structural units of the resin (A1). % Is more preferable, and 10 to 30 mol% is more preferable.

<Other structural units>
The resin (A1) preferably further has a structural unit other than the structural unit (I) and the structural unit (II). Such a structural unit is not particularly limited, and is a structural unit having no acid labile group (hereinafter sometimes referred to as “structural unit (III)”. (III) "). Resin (A1) may have only 1 type of structural unit (III), and may have multiple types.

  As the structural unit (III), for example, a structural unit having a hydroxy group and not having an acid labile group (hereinafter sometimes referred to as “structural unit (a2)”) and a lactone ring are included. And a structural unit having no acid labile group (hereinafter, sometimes referred to as “structural unit (a3)”). In the resist composition containing the resin (A1) having such a structural unit, the composition layer formed from the resist composition is excellent in adhesion to the substrate, and thus a high-resolution resist pattern can be produced. .

<Structural unit (a2)>
As the structural unit (a2), for example, a structural unit represented by the formula (a2-1) (hereinafter sometimes referred to as “structural unit (a2-1)”) and a formula (a2-0) are represented. A structural unit (hereinafter referred to as “structural unit (a2-0)” in some cases).

式（ａ２−１）中、
Ｌ^a3は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k2−ＣＯ−Ｏ−（ｋ２は１〜７の整数を表し、＊はカルボニル基（−ＣＯ−）との結合手を表す。）で表される基を表す。
Ｒ^a14は、水素原子又はメチル基を表す。
Ｒ^a15及びＲ^a16は、それぞれ独立に、水素原子、メチル基又はヒドロキシ基を表す。
ｏ１は、０〜１０の整数を表す。

In formula (a2-1),
L ^a3 is an oxygen atom or ^* —O— (CH ₂ ) _k2 —CO—O— (k2 represents an integer of 1 to 7, and * represents a bond to a carbonyl group (—CO—)). Represents the group represented.
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.

L ^a3 is preferably an oxygen atom or a group represented by —O— (CH ₂ ) _k2 —CO—O— in which k2 is an integer of 1 to 4, more preferably an oxygen atom or — O—CH ₂ —CO—O—, more preferably an oxygen atom.
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 the structural unit (a2-1), for example, the following can be mentioned, and preferably the formula (a2-1-1), the formula (a2-1-2), the formula (a2-1-3) or the formula ( a2-1-4), more preferably a structural unit represented by formula (a2-1-1) or formula (a2-1-3).

  The structural unit (a2-1) is derived from, for example, an acid stable monomer described in JP2010-204646A.

  When the resin (A1) has a structural unit (a2-1), the content is preferably 1 to 45 mol%, more preferably 1 to 40 mol%, based on all structural units of the resin (A1). 2 to 35 mol% is more preferable.

式（ａ２−０）中、
Ｒ^a30は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
Ｒ^a31は、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数２〜４のアシル基、炭素数２〜４のアシルオキシ基、アクリロイル基又はメタクリロイル基を表す。
ｍａは０〜４の整数を表す。ｍａが２以上の場合、複数のＲ^a31は同一でも異なっていてもよい。

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

^Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R ^a30 include the same groups as R ^{3 in the} formula (I). Among them, R ^a30 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.
The alkoxy group represented by R ^a31 is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and further preferably a methoxy group.
ma is preferably 0, 1 or 2, more preferably 0 or 1, and particularly preferably 0.

The structural unit (a2-0) is represented by, for example, the formula (a2-0-1), the formula (a2-0-2), the formula (a2-0-3), or the formula (a2-0-4). Can be mentioned. Examples of the monomer that derives the structural unit (a2-0) include monomers described in JP 2010-204634 A.

  Resin (A1) containing a structural unit (a2-0) uses the monomer which protected the phenolic hydroxy group which the monomer which derives | leads to a structural unit (a2-0) has, for example with protecting groups, such as an acetyl group It can be produced by conducting a polymerization reaction and then deprotecting. However, when the deprotection treatment is performed, the acid labile group possessed by the structural unit (II) must be not significantly impaired.

When forming a resist pattern, when a KrF excimer laser (wavelength: 248 nm) or a high energy beam such as an electron beam or EUV light is used as an exposure light source, the structural unit (a2-0) is used as the structural unit (a2). Is preferred. In this specification, irradiation with radiation such as an electron beam may be collectively referred to as “exposure”.
When an ArF excimer laser (wavelength: 193 nm) is used as the exposure light source, the structural unit (a2-1) is preferable as the structural unit (a2). Resin (A) may have only 1 type, or 2 or more types of structural units (a2).

  When the resin (A1) has a structural unit (a2-0), the content is preferably from 5 to 90 mol%, more preferably from 10 to 85 mol%, based on all structural units of the resin (A1). 15-80 mol% is more preferable.

<Structural unit (a3)>
The lactone ring contained in the structural unit (a3) may be monocyclic such as β-propiolactone ring, γ-butyrolactone ring and δ-valerolactone ring, and condensation of a monocyclic lactone ring with another ring. It may be a ring. Among these, a bridged ring including a γ-butyrolactone ring and a γ-butyrolactone ring structure is preferable.

［式（ａ３−１）中、
Ｌ^a4は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k3−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）で表される基を表す。＊はカルボニル基との結合手を表す。
Ｒ^a18は、水素原子又はメチル基を表す。
Ｒ^a21は炭素数１〜４の脂肪族炭化水素基を表す。
ｐ１は０〜５の整数を表す。ｐ１が２以上のとき、複数のＲ^a21は互いに同一又は相異なる。
式（ａ３−２）中、
Ｌ^a5は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k3−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）で表される基を表す。＊はカルボニル基との結合手を表す。
Ｒ^a19は、水素原子又はメチル基を表す。
Ｒ^a22は、カルボキシ基、シアノ基又は炭素数１〜４の脂肪族炭化水素基を表す。
ｑ１は、０〜３の整数を表す。ｑ１が２以上のとき、複数のＲ^a22は互いに同一又は相異なる。
式（ａ３−３）中、
Ｌ^a6は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k3−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）で表される基を表す。＊はカルボニル基との結合手を表す。
Ｒ^a20は、水素原子又はメチル基を表す。
Ｒ^a23は、カルボキシ基、シアノ基又は炭素数１〜４の脂肪族炭化水素基を表す。
ｒ１は、０〜３の整数を表す。ｒ１が２以上のとき、複数のＲ^a23は互いに同一又は相異なる。］ As the structural unit (a3), a structural unit represented by the formula (a3-1) (hereinafter sometimes referred to as “structural unit (a3-1)”), a structural unit represented by the formula (a3-2) (Hereinafter referred to as “structural unit (a3-2)” in some cases) and a structural unit represented by formula (a3-3) (hereinafter sometimes referred to as “structural unit (a3-3)”). . Resin (A1) may have only 1 type in these, and may have 2 or more types.

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

In formula (a3-1), formula (a3-2) and formula (a3-3), L ^a4 , L ^a5 and L ^a6 are the same as those described for L ^a3 in formula (a2-1). Can be mentioned.
L ^a4 , L ^a5 and L ^a6 are each independently preferably an oxygen atom or a group represented by * —O— (CH ₂ ) _k3 —CO—O—, wherein k3 is an integer of 1 to 4. An atom and * —O—CH ₂ —CO—O— are more preferable, and an oxygen atom is more preferable.
R ^a18 , R ^a20 and R ^a21 are preferably methyl groups.
R ^a22 and R ^a23 are each independently preferably a carboxy group, a cyano group or a methyl group.
p1, q1 and r1 are each independently preferably an integer of 0 to 2, more preferably 0 or 1.

The structural unit (a3-1) is represented by, for example, the formula (a3-1-1), the formula (a3-1-2), the formula (a3-1-3), or the formula (a3-1-4). Structural units.

The structural unit (a3-2) is represented by, for example, the formula (a3-2-1), the formula (a3-2-2), the formula (a3-2-3), or the formula (a3-2-4). Structural units.

The structural unit (a3-3) is represented by, for example, the formula (a3-3-1), the formula (a3-3-2), the formula (a3-3-3), or the formula (a3-3-4). Structural units.

  Examples of the monomer that derives the structural unit (a3-1), the structural unit (a3-2), and the structural unit (a3-3) include monomers described in JP 2010-204646 A. The structural unit (a3) is represented by any one of formula (a3-1-1), formula (a3-1-2), formula (a3-2-3), and formula (a3-2-4). A structural unit is preferable, and a structural unit represented by any one of formula (a3-1-1) and formula (a3-2-3) is more preferable.

  When the resin (A1) has the structural unit (a3), the content is preferably from 5 to 70 mol%, more preferably from 10 to 65 mol%, based on all the structural units of the resin (A1). -60 mol% is more preferable.

<Method for producing resin (A1)>
When the resin (A1) is a resin composed only of the structural unit (I) and the structural unit (II), these contents are respectively relative to the total structural units of the resin (A1).
Structural unit (I); 1 to 80 mol%
Structural unit (II); 20-99 mol%
Is preferred,
Structural unit (I); 5-65 mol%
Structural unit (II); 35-95 mol%
Is more preferable.
Such a resin (A1) can be produced by copolymerizing the compound (I ′) and the monomer (a1) by a known polymerization method (for example, radical polymerization method).

When resin (A) is resin which consists only of structural unit (I), structural unit (II), and structural unit (III), these content rates are respectively with respect to all the structural units of resin (A). ,
Structural unit (I); 1 to 80 mol%
Structural unit (II); 15-94 mol%
Structural unit (III); 5-84 mol%
Is preferred,
Structural unit (I); 5-65 mol%
Structural unit (II); 20 to 80 mol%
Structural unit (III); 15-75 mol%
Is more preferred,
Structural unit (I); 5 to 50 mol%
Structural unit (II); 30 to 75 mol%
Structural unit (III); 20-65 mol%
Is more preferred,
Structural unit (I); 5-35 mol%
Structural unit (II); 35-65 mol%
Structural unit (III); 30 to 60 mol%
Is particularly preferred.
Such a resin (A1) can be produced by copolymerizing the compound (I ′), the monomer (a1) and the monomer (III) by a known polymerization method (for example, radical polymerization method). The content rate of each structural unit which resin (A1) has can be adjusted with the usage-amount of the monomer used for copolymerization.

  The weight average molecular weight of the resin (A1) is preferably from 2,500 to 50,000, more preferably from 3,000 to 30,000. In addition, the weight average molecular weight here is calculated | required as a conversion value of a standard polystyrene reference | standard by gel permeation chromatography. Detailed analysis conditions for this analysis are described in the Examples of the present application.

<Resin (A2)>
The resin (A2) is a resin having a fluorine atom and dissolved in a negative developer, and specifically, a structural unit having a fluorine atom (hereinafter sometimes referred to as “structural unit (a4)”). And a resin that dissolves in a negative developer. The resin (A2) usually dissolves in the negative developer even after being subjected to the action of an acid. The structural unit having a fluorine atom is preferably a structural unit derived from a (meth) acrylic monomer having a fluorine atom.
When the negative developer contains at least one of butyl acetate and 2-heptanone, the resin (A2) has at least one selected from the group consisting of butyl acetate and 2-heptanone having fluorine atoms. Dissolve.
In the present specification, “dissolves in a negative developer” means that 10 g or more of a resin dissolves in 100 g of a negative developer at a temperature of about 23 ° C.

［式（ａ４−１）中、
Ｒ^a41は、炭素数１〜１２の１価の炭化水素基を表し、該炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
Ａ^a41は、置換基を有していてもよい炭素数１〜６のアルカンジイル基又は式（ａ−ｇ１）

（式（ａ−ｇ１）中、
ｓは０又は１を表す。
Ａ^a42及びＡ^a44は、それぞれ独立に、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基を表す。
Ａ^a43は、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基又は単結合を表す。
Ｘ^a41及びＸ^a42は、それぞれ独立に、酸素原子、カルボニル基、カルボニルオキシ基又はオキシカルボニル基を表す。
ただし、Ａ^a42、Ａ^a43、Ａ^a44、Ｘ^a41及びＸ^a42の炭素数の合計は７以下である。）
で表される基を表す。
Ｒ^a42は、置換基を有していてもよい炭素数１〜２０の炭化水素基であって、そのメチレン基がカルボニルオキシ基又はオキシカルボニル基で置換されてもよい炭化水素基を表す。
ただし、Ａ^a41及びＲ^a４２のうち少なくとも一方は、フッ素原子を有する基である。］ As a structural unit (a4), the structural unit represented by a formula (a4-1) is mentioned, for example.

[In the formula (a4-1),
R ^a41 represents a monovalent hydrocarbon group having 1 to 12 carbon atoms, and the methylene group constituting the hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
A ^a41 is an alkanediyl group having 1 to 6 carbon atoms which may have a substituent or a formula (a-g1).

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

芳香族炭化水素基としては、例えば、フェニル基、ナフチル基やビフェニリル基が挙げられる。 ^Examples of the hydrocarbon group represented by R ^a41 include chain and cyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and groups in which these are combined. Examples of the chain aliphatic hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, and a dodecyl group. Examples of the cyclic aliphatic hydrocarbon group include a cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* Represents a bond, and a polycyclic aliphatic hydrocarbon group.

Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and a biphenylyl group.

［式（ａ−ｇ２）中、
Ａ^a46は、炭素数１〜１７の脂肪族炭化水素基を表す。
Ｘ^a44は、カルボニルオキシ基又はオキシカルボニル基を表す。
Ａ^a47は、炭素数１〜１７の脂肪族炭化水素基を表す。
ただし、Ａ^a46、Ａ^a47及びＸ^a44の炭素数の合計は２０以下であり、Ａ^a46及びＡ^a47のうち、少なくとも一方は、少なくとも１つのフッ素原子を有する。］ ^Examples of the hydrocarbon group represented by R ^a42 include chain and cyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and groups in which these are combined, and chain and cyclic aliphatic groups. A hydrocarbon group and a group in which these are combined are preferable, and may have a carbon = carbon unsaturated bond, but a chain and cyclic aliphatic saturated hydrocarbon group and a group in which these are combined More preferred. Specifically, the same group as R ^a41 is ^exemplified .
R ^a42 is preferably a hydrocarbon group which may have a fluorine atom and a hydrocarbon in which the methylene group is substituted with a carbonyloxy group or an oxycarbonyl group, and an aliphatic hydrocarbon group having a fluorine atom and the formula ( An aliphatic hydrocarbon group having a group represented by a-g2) is more preferable.

[In the formula (a-g2),
A ^a46 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms.
X ^a44 represents a carbonyloxy group or an oxycarbonyl group.
A ^a47 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms.
However, the total number of carbon atoms of A ^a46 , A ^a47 and X ^a44 is 20 or less, and at least one of A ^a46 and A ^a47 has at least one fluorine atom. ]

When R ^a42 is an aliphatic hydrocarbon group having a fluorine atom, it is preferably a perfluoroalkyl group or a perfluorocycloalkyl group, more preferably a perfluoroalkyl group having 1 to 6 carbon atoms, and still more preferably a carbon number. 1 to 3 perfluoroalkyl groups. Examples of the perfluoroalkyl group include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, a perfluorohexyl group, a perfluoroheptyl group, and a perfluorooctyl group. Examples of the perfluorocycloalkyl group include a perfluorocyclohexyl group.

1-6 are preferable and, as for carbon number of the aliphatic hydrocarbon group represented by ^Aa46 , 1-3 are more preferable.
The aliphatic hydrocarbon group represented by A ^a47 preferably has 4 to 15 carbon atoms, more preferably 5 to 12 carbon atoms, and A ^a47 more preferably a cyclohexyl group or an adamantyl group.

Among the more preferable R ^a42 , the following structures are ^exemplified as those represented by * -A ^a46 -X ^a44 -A ^a47 (* is a bond to a carbonyl group).

^Examples of the alkanediyl group represented by A ^a41 include methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5- Linear alkanediyl group such as diyl group, hexane-1,6-diyl group; 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1 , 2-diyl group, 1-methylbutane-1,4-diyl group, 2-methylbutane-1,4-diyl group and the like branched alkanediyl groups.
^Examples of the substituent in the alkanediyl group represented by A ^a41 include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms.

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

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

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

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

Ａ^a41は、好ましくは炭素数１〜４のアルカンジイル基であり、より好ましくは炭素数２〜４のアルカンジイル基であり、さらに好ましくはエチレン基である。 Examples of the group (a-g1) in which X ^a42 is an oxycarbonyl group include the following groups.

A ^a41 is preferably an alkanediyl group having 1 to 4 carbon atoms, more preferably an alkanediyl group having 2 to 4 carbon atoms, and still more preferably an ethylene group.

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

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

^Examples of the alkanediyl group represented by A ^f1 include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, and a pentane-1,5- Linear alkanediyl group such as diyl group, hexane-1,6-diyl group; 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1 , 2-diyl group, 1-methylbutane-1,4-diyl group, 2-methylbutane-1,4-diyl group and the like branched alkanediyl groups.

Examples of the hydrocarbon group having a fluorine atom represented by R ^f2 include an alkyl group having a fluorine atom and an alicyclic hydrocarbon group having a fluorine atom.
Specifically, as the alkyl group having a fluorine atom, a difluoromethyl group, a trifluoromethyl group, a 1,1-difluoroethyl group, a 2,2-difluoroethyl group, a 2,2,2-trifluoroethyl group, Perfluoroethyl group, 1,1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1- (trifluoromethyl) -1,2 , 2,2-tetrafluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group, 1,1,2, 2,3,3,4,4-octafluorobutyl group, perfluorobutyl group, 1,1-bis (trifluoro) methyl-2,2,2-trifluoroethyl group, 2- (perfluoro (Ropropyl) ethyl group, 1,1,2,2,3,3,4,4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3,4,4,5,5- Decafluoropentyl group, 1,1-bis (trifluoromethyl) -2,2,3,3,3-pentafluoropropyl group, perfluoropentyl group, 2- (perfluorobutyl) ethyl group, 1,1,2, 2,3,3,4,4,5,5-decafluorohexyl group, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl group, perfluoropentyl Examples thereof include fluorinated alkyl groups such as a methyl group and a perfluorohexyl group.
Examples of the alicyclic hydrocarbon group having a fluorine atom include fluorinated cycloalkyl groups such as a perfluorocyclohexyl group and a perfluoroadamantyl group.

In Formula (a4-2), as A ^f1 , an alkanediyl group having 2 to 4 carbon atoms is preferable, and an ethylene group is more preferable.
R ^f2 is preferably a fluorinated alkyl group having 1 to 6 carbon atoms.

［式（ａ４−３）中、
Ｒ^ｆ11は、水素原子又はメチル基を表す。
Ａ^ｆ11は、炭素数１〜６のアルカンジイル基を表す。
Ａ^ｆ13は、フッ素原子を有していてもよい炭素数１〜１８の脂肪族炭化水素基を表す。
Ｘ^ｆ12は、カルボニルオキシ基又はオキシカルボニル基を表す。
Ａ^ｆ14は、フッ素原子を有していてもよい炭素数１〜１８の脂肪族炭化水素基を表す。 ただし、Ａ^ｆ13及びＡ^ｆ14の少なくとも１つは、フッ素原子を有する脂肪族炭化水素基を表す。］

[In the formula (a4-3),
R ^f11 represents a hydrogen atom or a methyl group.
A ^f11 represents an alkanediyl group having 1 to 6 carbon atoms.
A ^f13 represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a fluorine atom.
X ^f12 represents a carbonyloxy group or an oxycarbonyl group.
A ^f14 represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a fluorine atom. However, at least one of A ^f13 and A ^f14 represents an aliphatic hydrocarbon group having a fluorine atom. ]

^Examples of the alkanediyl group represented by A ^f11 include the same groups as the alkanediyl group of A ^f1 .

The aliphatic hydrocarbon group represented by A ^f13 includes either a chain or a cyclic group, and a divalent aliphatic hydrocarbon group in which these are combined. The aliphatic hydrocarbon may have a carbon-carbon unsaturated bond, but is preferably a saturated aliphatic hydrocarbon group.
The aliphatic hydrocarbon group ^optionally having a fluorine atom represented by A ^f13 is preferably an aliphatic saturated hydrocarbon group optionally having a fluorine atom, more preferably a perfluoroalkanediyl group. is there.
Examples of the divalent chain aliphatic hydrocarbon group which may have a fluorine atom include alkanediyl groups such as methylene group, ethylene group, propanediyl group, butanediyl group and pentanediyl group; difluoromethylene group, perfluoroethylene Groups, perfluoroalkanediyl groups such as perfluoropropanediyl group, perfluorobutanediyl group and perfluoropentanediyl group; and the like.
The divalent cyclic aliphatic hydrocarbon group which may have a fluorine atom may be either monocyclic or polycyclic. Examples of the monocyclic aliphatic hydrocarbon group include a cyclohexanediyl group and a perfluorocyclohexanediyl group. Examples of the polycyclic divalent aliphatic hydrocarbon group include an adamantanediyl group, a norbornanediyl group, a perfluoroadamantanediyl group, and the like.

The aliphatic hydrocarbon group represented by A ^f14 includes either a chain or a cyclic group, and an aliphatic hydrocarbon group in which these are combined. The aliphatic hydrocarbon may have a carbon-carbon unsaturated bond, but is preferably a saturated aliphatic hydrocarbon group.
The aliphatic hydrocarbon group which may have a fluorine atom represented by A ^f14 is preferably an aliphatic saturated hydrocarbon group which may have a fluorine atom.
Examples of the chain aliphatic hydrocarbon group which may have a fluorine atom include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 1,1,1-trifluoroethyl group, 1,1 , 2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 1,1,1,2,2-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2,2,3,3 , 4,4-octafluorobutyl group, butyl group, perfluoropentyl group, 1,1,1,2,2,3,3,4,4-nonafluoropentyl group and pentyl group, hexyl group, perfluorohexyl group, A heptyl group, a perfluoro heptyl group, an octyl group, a perfluorooctyl group, etc. are mentioned.
Etc.
The cyclic aliphatic hydrocarbon group which may have a fluorine atom may be monocyclic or polycyclic. Examples of the group containing a monocyclic aliphatic hydrocarbon group include a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, and a perfluorocyclohexyl group. Examples of the group containing a polycyclic aliphatic hydrocarbon group include an adamantyl group, an adamantylmethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group, and a perfluoroadamantylmethyl group.

In the formula (a4-3), examples of ^{A f11,} ethylene group is preferable.
The aliphatic hydrocarbon group represented by A ^f13 preferably has 1 to 6 carbon atoms, and more preferably has 2 to 3 carbon atoms.
The aliphatic hydrocarbon group represented by A ^f14 has preferably 3 to 12 carbon atoms, and more preferably 3 to 10 carbon atoms. Among them, A ^f14 is preferably a group containing an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a cyclopropylmethyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group.

As a monomer which derives the structural unit represented by the formula (a4-2), for example, the formula (a4-1-1), the formula (a4-1-2), the formula (a4-1-3), the formula ( a4-1-4), formula (a4-1-5), formula (a4-1-6), formula (a4-1-7), formula (a4-1-8), formula (a4-1-9) ), Formula (a4-1-10), formula (a4-1-11), formula (a4-1-12), formula (a4-1-13), formula (a4-1-14), formula (a4) -1-15), formula (a4-1-16), formula (a4-1-17), formula (a4-1-18), formula (a4-1-19), formula (a4-1-20) , Monomers represented by formula (a4-1-21) or formula (a4-1-22), respectively.

Examples of the monomer for deriving the structural unit represented by formula (a4-3) include formula (a4-1′-1), formula (a4-1′-2), and formula (a4-1′-3). , Formula (a4-1′-4), Formula (a4-1′-5), Formula (a4-1′-6), Formula (a4-1′-7), Formula (a4-1′-8) , Formula (a4-1′-9), Formula (a4-1′-10), Formula (a4-1′-11), Formula (a4-1′-12), Formula (a4-1′-13) , Formula (a4-1′-14), Formula (a4-1′-15), Formula (a4-1′-16), Formula (a4-1′-17), Formula (a4-1′-18) , Monomers represented by formula (a4-1′-19), formula (a4-1′-20), formula (a4-1-21), or formula (a4-1′-22), respectively.

［式（ａ４−４）中、
Ｒ^f21は、水素原子又はメチル基を表す。
Ａ^f21は、−（ＣＨ_２）_ｊ１−、−（ＣＨ_２）_ｊ２−Ｏ−（ＣＨ_２）_ｊ３−又は−（ＣＨ_２）_ｊ４−ＣＯ−Ｏ−（ＣＨ_２）_ｊ５−を表す。
ｊ１、ｊ２、ｊ３、ｊ４及びｊ５は、それぞれ独立に、１〜６の整数を表す。
Ｒ^f22は、フッ素原子を有する炭素数１〜１０の炭化水素基を表す。］ Examples of the structural unit (a4) include a structural unit represented by the formula (a4-4).

[In the formula (a4-4),
R ^f21 represents a hydrogen atom or a methyl group.
A ^f21 represents — (CH ₂ ) _j1 —, — (CH ₂ ) _j2 —O— (CH ₂ ) _j3 — or — (CH ₂ ) _j4 —CO—O— (CH ₂ ) _j5 —.
j1, j2, j3, j4 and j5 each independently represent an integer of 1 to 6.
R ^f22 represents a C 1-10 hydrocarbon group having a fluorine atom. ]

^Examples of the hydrocarbon group having a fluorine atom represented by R ^f22 include the same hydrocarbon groups as represented by R ^f2 in formula (a4-2). R ^f22 is preferably a ^C 1-10 alkyl group having a fluorine atom or a C 3-10 alicyclic hydrocarbon group having a fluorine atom, more preferably a C 1-10 alkyl group having a fluorine atom. Preferably, the C1-C6 alkyl group which has a fluorine atom is further more preferable.

As A ^f21 , — (CH ₂ ) _j1 — is preferable, an ethylene group or a methylene group is more preferable, and a methylene group is further preferable.

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

Further, examples of the monomer for deriving the structural unit (a4) include the monomers shown below.

  The resin (A2) may have a single structural unit (a4) or a plurality of types. Further, the resin (A2) may have a structural unit having no fluorine atom. Examples of such a structural unit include the structural unit (II), the structural unit (III), a structural unit derived from adamantane methacrylate, a structural unit derived from cyclohexyl methacrylate, and the like.

  The content of the structural unit (a4) is generally 5 mol% or more, preferably 10 mol% or more, more preferably 50 mol% or more, and more preferably 80 mol% or more with respect to all the structural units of the resin (A2). More preferably, it is particularly preferable that it substantially comprises only the structural unit (a4).

  The resin (A2) can be produced by polymerizing a monomer for deriving the structural unit (a4) and other monomers used as necessary by a known polymerization method (for example, radical polymerization method). The content rate of each structural unit which resin (A2) has can be adjusted with the usage-amount of the monomer used for copolymerization.

  The weight average molecular weight of the resin (A2) is preferably 5,000 to 80,000, more preferably 7,000 to 50,000. This weight average molecular weight is also obtained as a converted value based on standard polystyrene by gel permeation chromatography, and detailed analysis conditions for the analysis will be described in detail in Examples of the present application.

  The content of the resin (A2) is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, and further preferably 2 to 40 parts by mass with respect to 100 parts by mass of the resin (A1). Yes, particularly preferably 3 to 30 parts by mass.

<Resin other than (A1) and (A2)>
The resist composition may contain a resin other than the resins (A1) and (A2). Examples of such a resin include a resin composed only of the structural unit (II), a resin composed of the structural unit (II) and the structural unit (III), and a resin composed only of the structural unit (III).
The content of the resin other than the resins (A1) and (A2) is preferably 20% by mass or less, more preferably 10% by mass or less, and substantially contained with respect to the total amount of the resins contained in the resist composition. More preferably not.

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

<Acid generator (B)>
The acid generator (B) may be a nonionic acid generator, an ionic acid generator, or a combination thereof. Nonionic acid generators 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. Furthermore, a compound that generates an acid by radiation, such as a photocationic polymerization initiator, a photodecoloring agent for dyes, or a photochromic agent, can also be used.
Moreover, what was manufactured by the well-known method can be used for an acid generator (B).

［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、炭素数１〜２４、好ましくは１〜１７、の脂肪族飽和炭化水素基を表し、該脂肪族飽和炭化水素基に含まれる水素原子は、フッ素原子又はヒドロキシ基で置換されていてもよく、該脂肪族飽和炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
Ｙは、水素原子、フッ素原子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、該脂環式炭化水素基を構成するメチレン基は、酸素原子、スルホニル基又はカルボニル基に置き換わっていてもよい。
Ｚ⁺は、有機カチオンを表す。］ The acid generator (B) is preferably a fluorine-containing acid generator, more preferably an acid generator represented by the formula (B1) (hereinafter sometimes referred to as “acid generator (B1)”). .

[In the formula (B1),
Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents an aliphatic saturated hydrocarbon group having 1 to 24 carbon atoms, preferably 1 to 17 carbon atoms, and the hydrogen atom contained in the aliphatic saturated hydrocarbon group is substituted with a fluorine atom or a hydroxy group. Alternatively, the methylene group constituting the aliphatic saturated hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
Y represents a hydrogen atom, a fluorine atom or a C3-C18 alicyclic hydrocarbon group which may have a substituent, and the methylene group constituting the alicyclic hydrocarbon group is an oxygen atom, A sulfonyl group or a carbonyl group may be substituted.
Z ⁺ represents an organic cation. ]

The perfluoroalkyl group of Q ¹ and Q ² is one in which all of the hydrogen atoms constituting the alkyl group having 1 to 6 carbon atoms are replaced with fluorine atoms. For example, a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group Perfluoroisopropyl group, perfluorobutyl group, perfluoro sec-butyl group, perfluoro tert-butyl group, perfluoropentyl group, perfluorohexyl group and the like.
Q ¹ and Q ² are preferably each independently a trifluoromethyl group or a fluorine atom, and more preferably a fluorine atom.

Examples of the aliphatic saturated hydrocarbon group represented by L ^b1 include a linear alkanediyl group and a branched alkanediyl group.
Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1 , 6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group , Dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1, Linear alkanediyl groups such as 17-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group and propane-2,2-diyl group;
1-methylbutane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1, Branched alkanediyl groups such as 4-diyl groups;
Etc.

各式中、
Ｌ^b2は、単結合又は炭素数１〜２２、好ましくは１〜１５の脂肪族飽和炭化水素基を表す。
Ｌ^b3は、単結合又は炭素数１〜１９、好ましくは１〜１２の脂肪族飽和炭化水素基を表す。
Ｌ^b4は、炭素数１〜２０、好ましくは１〜１３の脂肪族飽和炭化水素基を表す。但しＬ^b3及びＬ^b4の合計炭素数の上限は２０、好ましくは１３である。
Ｌ^b５は、単結合又は炭素数１〜２１、好ましくは１〜１４の脂肪族飽和炭化水素基を表す。
Ｌ^b６は、炭素数１〜２２、好ましくは１〜１５の脂肪族飽和炭化水素基を表す。但しＬ^b5及びＬ^b6の合計炭素数の上限は２２、好ましくは１５である。
Ｌ^b７は、単結合又は炭素数１〜２２、好ましくは１５の脂肪族飽和炭化水素基を表す。
Ｌ^b８は、炭素数１〜２３、好ましくは１〜１６の脂肪族飽和炭化水素基を表す。但しＬ^b７及びＬ^b８の合計炭素数の上限は２３、好ましくは１〜１７である。
Ｌ^b9は、単結合又は炭素数１〜２０、好ましくは１〜１３の脂肪族飽和炭化水素基を表す。
Ｌ^b10は、炭素数１〜２１、好ましくは１〜１４の脂肪族飽和炭化水素基を表す。但しＬ^b9及びＬ^b10の合計炭素数の上限は２１、好ましくは１４である。
Ｌ^b11及びＬ^b12は、単結合又は炭素数１〜１８、好ましくは１〜１１の脂肪族飽和炭化水素基を表す。
Ｌ^b13は、炭素数１〜１９、好ましくは１〜１２の脂肪族飽和炭化水素基を表す。但しＬ^b11、Ｌ^b12及びＬ^b13の合計炭素数の上限は１９、好ましくは１２である。
Ｌ^b14及びＬ^b15は、それぞれ独立に、単結合又は炭素数１〜２０、好ましくは１〜１３の脂肪族飽和炭化水素基を表す。
Ｌ^b16は、炭素数１〜２１、好ましくは１〜１４の脂肪族飽和炭化水素基を表す。但しＬ^b14、Ｌ^b15及びＬ^b16の合計炭素数の上限は２１、好ましくは１４である。 Examples of the aliphatic saturated hydrocarbon group represented by L ^b1 in which the methylene group is replaced by an oxygen atom or a carbonyl group include, for example, formula (b1-1), formula (b1-2), formula (b1- 3), groups represented by any one of formula (b1-4), formula (b1-5), formula (b1-6) and formula (b1-7). The left and right sides are described in accordance with the formula (B1). Of the two bonds represented by *, each is coupled with C (Q ¹ ) (Q ² ) on the left and coupled with Y on the right. To do. The following formula (b1-1), formula (b1-2), formula (b1-3), formula (b1-4), formula (b1-5), formula (b1-6), and formula (b1-7) This also applies to the specific example.

In each formula,
L ^b2 represents a single bond or an aliphatic saturated hydrocarbon group having 1 to 22 carbon atoms, preferably 1 to 15 carbon atoms.
L ^b3 represents a single bond or an aliphatic saturated hydrocarbon group having 1 to 19 carbon atoms, preferably 1 to 12 carbon atoms.
L ^b4 represents an aliphatic saturated hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 13 carbon atoms. However, the upper limit of the total carbon number of L ^b3 and L ^b4 is 20, preferably 13.
L ^b5 represents a single bond or an aliphatic saturated hydrocarbon group having 1 to 21 carbon atoms, preferably 1 to 14 carbon atoms.
L ^b6 represents an aliphatic saturated hydrocarbon group having 1 to 22 carbon atoms, preferably 1 to 15 carbon atoms. However, the upper limit of the total carbon number of L ^b5 and L ^b6 is 22, preferably 15.
L ^b7 represents a single bond or an aliphatic saturated hydrocarbon group having 1 to 22 carbon atoms, preferably 15 carbon atoms.
L ^b8 represents an aliphatic saturated hydrocarbon group having 1 to 23 carbon atoms, preferably 1 to 16 carbon atoms. However, the upper limit of the total carbon number of L ^b7 and L ^b8 is 23, preferably 1-17.
L ^b9 represents a single bond or an aliphatic saturated hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 13 carbon atoms.
L ^b10 represents an aliphatic saturated hydrocarbon group having 1 to 21 carbon atoms, preferably 1 to 14 carbon atoms. However, the upper limit of the total carbon number of L ^b9 and L ^b10 is 21, preferably 14.
L ^b11 and L ^{b12 each} represents a single bond or an aliphatic saturated hydrocarbon group having 1 to 18 carbon atoms, preferably 1 to 11 carbon atoms.
L ^b13 represents an aliphatic saturated hydrocarbon group having 1 to 19 carbon atoms, preferably 1 to 12 carbon atoms. However, the upper limit of the total carbon number of L ^b11 , L ^b12 and L ^b13 is 19, preferably 12.
L ^b14 and L ^b15 each independently represent a single bond or an aliphatic saturated hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 13 carbon atoms.
L ^b16 represents an aliphatic saturated hydrocarbon group having 1 to 21 carbon atoms, preferably 1 to 14 carbon atoms. However, the upper limit of the total carbon number of L ^b14 , L ^b15 and L ^b16 is 21, preferably 14.

L ^b1 is preferably a group represented by the formula (b1-1), and a group represented by the formula (b1-1) in which L ^b2 is a single bond or an aliphatic saturated hydrocarbon group having 1 to 6 carbon atoms. More preferred.

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 divalent group represented by the formula (b1-7) include the following.

Specific examples of the group in which the hydrogen atom contained in the aliphatic saturated hydrocarbon group represented by L ^b1 is substituted with a fluorine atom or a hydroxy group include the following.

Y represents a hydrogen atom, a fluorine atom or an alicyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent.
Examples of the substituent that the alicyclic hydrocarbon group represented by Y may have include a halogen atom, a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, and carbon. An aralkyl group having 7 to 21 carbon atoms, an acyl group having 2 to 4 carbon atoms, a glycidyloxy group, or a group represented by — (CH ₂ ) _j2 —O—CO—R ^b1 (wherein R ^b1 is a carbon number of 1; Represents a hydrocarbon group of ˜16.j2 represents an integer of 0 to 4.) and the like. The aromatic hydrocarbon group and the aralkyl group may further have, for example, an alkyl group, a halogen atom, or a hydroxy group.

  Examples of the group in which the methylene group constituting the alicyclic hydrocarbon group represented by Y is replaced by an oxygen atom, a sulfonyl group or a carbonyl group include a cyclic ether group (1 of the methylene group constituting the alicyclic hydrocarbon group). Group in which one or two are replaced with oxygen atoms), a cyclic ketone group (a group in which one or two of the methylene groups constituting the alicyclic hydrocarbon group are replaced with carbonyl groups), a sultone ring group (an alicyclic hydrocarbon) Two adjacent methylene groups among the methylene groups constituting the group are groups in which oxygen atoms and sulfonyl groups are substituted, respectively, and two adjacent methylene groups constituting the alicyclic hydrocarbon group. Groups in which a methylene group is replaced by an oxygen atom and a carbonyl group, respectively).

Examples of the alicyclic hydrocarbon group represented by Y include groups represented by formulas (Y1) to (Y26), and include formula (Y11), formula (Y14), formula (Y15), and formula. A group represented by (Y16) or formula (Y19) is preferred, a group represented by formula (Y11), formula (Y14), formula (Y15) or formula (Y19) is more preferred, and formula (Y11) or formula The group represented by (Y14) is more preferable.

Examples of Y that is an alicyclic hydrocarbon group having a substituent include the following.

Among them, Y is preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, and the methylene group constituting the alicyclic hydrocarbon group is an oxygen atom or An alicyclic hydrocarbon group which may be replaced by a carbonyl group,
More preferably, there is an alicyclic hydrocarbon group having 3 to 12 carbon atoms which may have a substituent, and the methylene group constituting the alicyclic hydrocarbon group is replaced with an oxygen atom or a carbonyl group. An alicyclic hydrocarbon group,
More preferably, an adamantyl group which may have a substituent, and the methylene group constituting the alicyclic hydrocarbon group may be an alicyclic hydrocarbon group which may be replaced by an oxygen atom or a carbonyl group. And
An adamantyl group, an oxoadamantyl group or a hydroxyadamantyl group is particularly preferred. When Y is any of these groups, it is easy to produce the acid generator (B1), and a resist pattern particularly excellent in LER can be produced from a resist composition containing such an acid generator (B1). preferable.

Examples of the sulfonate anion constituting the acid generator (B1) include the formula (b1-1-1), the formula (b1-1-2), the formula (b1-1-3), and the formula (b1-1). 4), formula (b1-1-5), formula (b1-1-6), formula (b1-1-7), formula (b1-1-8), or formula (b1-1-9) And the anion represented. 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 include the anions described in JP 2010-204646 A.

Examples of the organic cation represented by Z ⁺ include an organic onium cation such as an organic sulfonium cation, an organic iodonium cation, an organic ammonium cation, a benzothiazolium cation, and an organic phosphonium cation. Among these, an organic sulfonium cation and an organic iodonium cation are preferable, and the organic cation represented by any one of the formula (b2-1), the formula (b2-2), the formula (b2-3), and the formula (b2-4) [Hereinafter, it may be referred to as “cation (b2-1)” or the like depending on the number of each formula. ] Is more preferable.

In formula (b2-1), formula (b2-2), formula (b2-3) and formula (b2-4),
R ^b4 , R ^b5 and R ^b6 each independently represent a hydrocarbon group having 1 to 30 carbon atoms, and among these hydrocarbon groups, an alkyl group having 1 to 30 carbon atoms and an oil having 3 to 18 carbon atoms A cyclic hydrocarbon group and an aromatic hydrocarbon group having 6 to 18 carbon atoms are preferred. The hydrogen atom contained in the alkyl group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and is included in the alicyclic hydrocarbon group. The hydrogen atom may be substituted with a halogen atom, an acyl group having 2 to 4 carbon atoms or a glycidyloxy group, and the hydrogen atom contained in the aromatic hydrocarbon group is a halogen atom, a hydroxy group, or a carbon number of 1 It may be substituted with an -18 alkyl group, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
Any two of R ^b4 , R ^b5 and R ^b6 are bonded to each other together with the sulfur atom to which they are bonded to form a 3- to 12-membered ring (preferably a 3- to 7-membered ring). The 3-membered to 12-membered ring represented by any two of R ^b4 , R ^b5 and R ^b6 may have an oxygen 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 represent 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 constituting 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 ^b12 represents a hydrocarbon group having 1 to 18 carbon atoms. Examples of the hydrocarbon group include an alkyl group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. Preferably, the hydrocarbon group represents 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, and the aromatic hydrocarbon group The hydrogen atom contained in the group is 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. May be substituted.
R ^b11 and R ^b12 may form a ^3- to 12-membered ring (preferably a 3- to 7-membered ring) together with —CH—CO— to which they are bonded, and methylene constituting the ring The group may be replaced with an oxygen atom, a sulfur atom or a carbonyl group.

^{R b13, R b14, R b15} , R b16, R b17 and R ^b18 each independently represent a hydroxy group, an alkyl group or an alkoxy group having 1 to 12 carbon atoms 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.

アルキルカルボニルオキシ基としては、メチルカルボニルオキシ基、エチルカルボニルオキシ基、ｎ−プロピルカルボニルオキシ基、イソプロピルカルボニルオキシ基、ｎ−ブチルカルボニルオキシ基、ｓｅｃ−ブチルカルボニルオキシ基、ｔｅｒｔ−ブチルカルボニルオキシ基、ペンチルカルボニルオキシ基、ヘキシルカルボニルオキシ基、オクチルカルボニルオキシ基及び２−エチルヘキシルカルボニルオキシ基等が挙げられる。
芳香族炭化水素基としては、例えば、フェニル基、４−メチルフェニル基、４−エチルフェニル基、４−ｔｅｒｔ−ブチルフェニル基、４−シクロへキシルフェニル基、４−メトキシフェニル基、ビフェニリル基及びナフチ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, and examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Cycloalkyl groups such as cycloheptyl group, cyclooctyl group, and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, and the following groups. * Represents a bond.

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.
Examples of the aromatic hydrocarbon group include 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 the like. A naphthyl group etc. are mentioned.

Among the groups represented by R ^b12 , an alkyl group in which a hydrogen atom is substituted with an aromatic hydrocarbon group, that is, an aralkyl group includes a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, a naphthylethyl group, etc. Is mentioned.
Examples of the ring formed by combining R ^b9 and R ^b10 include a thiolane-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, and a 1,4-oxathian-4-ium ring. It is done.
^Examples of the ring formed by combining R ^b11 and R ^b12 include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

  Specific examples of the organic cation represented by the formula (b2-1), the formula (b2-2), the formula (b2-3), or the formula (b2-4) are those described in JP 2010-204646 A Can be mentioned.

式（ｂ２−１−１）中、
Ｒ^b19、Ｒ^b20及びＲ^b21は、それぞれ独立に、ハロゲン原子（より好ましくはフッ素原子）、ヒドロキシ基、炭素数１〜１８の脂肪族炭化水素基又は炭素数１〜１２のアルコキシ基を表す。また、Ｒ^b19、Ｒ^b20及びＲ^b21から選ばれる２つが一緒になってイオウ原子を含む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は同一でも異なっていてもよく、ｗ２が２以上のとき、複数のＲ^b20は同一でも異なっていてもよく、ｘ２が２以上のとき、複数のＲ^b21は同一でも異なっていてもよい。
Ｒ^b19、Ｒ^b20及びＲ^b21で表される脂肪族炭化水素基としては、アルキル基及び脂環式炭化水素基が挙げられ、好ましくは炭素数１〜１２のアルキル基又は炭素数４〜１８の脂環式炭化水素基である。
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。 Among them, the organic cation Z ⁺ is preferably an organic sulfonium cation, more preferably a cation (b2-1), and an organic cation represented by the formula (b2-1-1) [hereinafter referred to as “cation (b2-1-1)”. " ] Is more preferred, and triphenylsulfonium cation (in formula (b2-1-1), v2 = w2 = x2 = 0) or tolylsulfonium cation (in formula (b2-1-1), v2 = w2 = X2 = 1, and R ^b19 , R ^b20 and R ^b21 are all methyl groups).

In formula (b2-1-1),
R ^b19 , R ^b20 and R ^b21 each independently represent a halogen atom (more preferably a fluorine atom), a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. ^Further , two selected from R ^b19 , R ^b20 and R ^b21 may be combined to form a ring containing a sulfur atom.
v2, w2 and x2 each independently represent an integer of 0 to 5 (preferably 0 or 1).
When v2 is 2 or more, a plurality of R ^b19 may be the same or different. When w2 is 2 or more, a plurality of R ^b20 may be the same or different. When x2 is 2 or more, a plurality of R ^{b19 b21} may be the same or different.
^Examples of the aliphatic hydrocarbon group represented by R ^b19 , R ^b20, and R ^b21 include an alkyl group and an alicyclic hydrocarbon group, preferably an alkyl group having 1 to 12 carbon atoms or an alkyl group having 4 to 18 carbon atoms. An alicyclic hydrocarbon group.
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. .

Examples of the cation (b2-1-1) include the following cations.

Examples of the cation (b2-2) include the following cations.

Examples of the cation (b2-3) include the following cations.

  The acid generator (B1) is a combination of the above sulfonic acid anion and the above organic cation. The above-mentioned anion and cation can be arbitrarily combined, and preferably the formula (b1-1-1), formula (b1-1-2), formula (b1-1-3), formula (b1-1-1) 4) any one of formula (b1-1-5), formula (b1-1-6), formula (b1-1-7), formula (b1-1-8) and formula (b1-1-9) A combination of a sulfonate anion represented by formula (b2-1-1) and an organic cation represented by formula (b2-1-1), and formula (b1-1-3), formula (b1-1-4) and formula (b1) A combination of a sulfonate anion represented by any one of (1-5) and an organic cation represented by the formula (b2-3) is exemplified.

  As the acid generator (B1), those represented by the formulas (B1-1) to (B1-24) are more preferable, and the formula (B1-1) and the formula (B) containing a triarylsulfonium cation are preferable. B1-2), Formula (B1-3), Formula (B1-6), Formula (B1-7), Formula (B1-11), Formula (B1-12), Formula (B1-13), Formula (B1) -14), formula (B1-18), formula (B1-19), formula (B1-20), formula (B1-21), formula (B1-22), formula (B1-23) and formula (B1- Those represented by 24) are particularly preferred.

  When the acid generator (B) contains the acid generator (B1), the content is preferably 70% by mass or more, more preferably 90% by mass or more, based on the total amount of the acid generator (B). In particular, it is more preferably composed of only the acid generator (B1).

  The content of the acid generator (B) is preferably 1 to 40 parts by mass and more preferably 3 to 35 parts by mass with respect to 100 parts by mass of the total amount of the resin.

<Basic compound (C)>
The resist composition preferably contains a basic compound (C). Such a basic compound (C) is called “quencher” in the resist field. 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. As the basic compound (C), the formula (C1), the formula (C2), the formula (C3), the formula (C4), the formula (C5), the formula (C6), the formula (C7), and the formula (C8) are preferable. The compound represented by either of these is mentioned, More preferably, the compound represented by Formula (C1-1) is mentioned.

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

［式（Ｃ１−１）中、
Ｒ^c2及びＲ^c3は、前記と同義である。
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、互いに同一でも異なってもよい。］

[In the formula (C1-1),
R ^c2 and R ^c3 are as defined 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, a plurality of R ^{c4 s} may be the same as or different from each other. ]

［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と同義である。
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、互いに同一でも異なってもよい。］

[In Formula (C2), Formula (C3) and Formula (C4),
R ^c5 , R ^c6 , R ^c7 and R ^c8 are each independently synonymous with 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 may be the same as or different from each other. ]

［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と同義である。
Ｒ^c14、Ｒ^c15及びＲ^c17は、それぞれ独立に、Ｒ^c4と同義である。
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は互いに同一でも異なってもよい。ｐ３が２以上であるとき、複数のＲ^c15は互いに同一でも異なってもよい。
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 are each independently synonymous with R ^c1 .
R ^c14 , R ^c15 and R ^c17 each independently have the same ^meaning as R ^c4 .
o3 and p3 each independently represent an integer of 0 to 3, and when o3 is 2 or more, the plurality of R ^c14 may be the same or different from each other. When p3 is 2 or more, the plurality of R ^c15 may be the same as or different from each other.
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と同義である。
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は互いに同一でも異なってもよい。ｒ３が２以上であるとき、複数のＲ^c19は互いに同一でも異なってもよい。ｓ３が２以上であるとき、複数のＲ^c20は互いに同一でも異なってもよい。
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。］

[In Formula (C7) and Formula (C8),
R ^c18, R ^c19 and R ^c20 in each occurrence independently has 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 may be the same or different from each other. When r3 is 2 or more, the plurality of R ^c19 may be the same as or different from each other. When s3 is 2 or more, the plurality of R ^c20 may be the same as or different from each other.
L ^c2 represents a single bond or an alkanediyl group having 1 to 6 carbon atoms, —CO—, —C (═NH) —, —S—, or a divalent group obtained by combining these. ]

In formula (C1), formula (C2), formula (C3), formula (C4), formula (C5), formula (C6), formula (C7), formula (C8) and formula (C1-1), alkyl Examples of the group, alicyclic hydrocarbon group, aromatic hydrocarbon group, alkoxy group and 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, and 4,4′-diamino-3,3′-diethyldiphenylmethane. Ropiruanirin. 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.

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

<Solvent (D)>
The solvent (D) is appropriately determined depending on the types and amounts of the resin (A1), the resin (A2), the acid generator (B), and the like, and further considering the applicability when applying the resist composition on the substrate. , You can choose the best one.

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

  The content of the solvent (D) is usually 90% by mass or more, preferably 92% by mass or more, more preferably 94% by mass or more, and usually 99.9% by mass or less, preferably based on the total amount of the resist composition. Is 99 mass% or less.

<Other ingredients>
The resist composition may contain components other than the above-described components (hereinafter sometimes referred to as “component (F)”) as necessary. As the component (F), known additives in the resist field, such as a sensitizer, a dissolution inhibitor, a surfactant, a stabilizer and a dye can be used.
When the resist composition contains the component (F), an appropriate content can be determined according to the type of the component (F).

<Method for preparing resist composition>
The resist composition is prepared by mixing the resin (A1), the resin (A2), the acid generator (B) and the solvent (D), and the basic compound (C) and component (F) used as necessary. can do. 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 a solvent (D), etc. The mixing time can be appropriately 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.
Thus, after mixing each component, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm.

  The method for producing a resist pattern of the present invention can produce a negative resist pattern having excellent line edge roughness (LER), and thus is useful for fine processing of semiconductors.

In Examples and Comparative Examples, the content and the amount used are represented. “%” And “parts” are based on mass unless otherwise specified.
The weight average molecular weight is a value obtained by gel permeation chromatography under the following conditions.
Apparatus: HLC-8120GPC type (manufactured by Tosoh Corporation)
Column: TSKgel Multipore H _XL -M x 3 + guardcolumn (Tosoh Corporation)
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Detector: RI detector Column temperature: 40 ° C
Injection volume: 100 μL
Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation)

  The structure of the compound was confirmed by measuring the molecular peak using mass spectrometry (LC is model 1100 manufactured by Agilent, and MASS is LC / MSD manufactured by Agilent).

式（Ｈ−２）で表される化合物８８．００部、メチルイソブチルケトン６１６．００部及びピリジン６０．９８部を、２３℃で３０分間攪拌混合し、０℃まで冷却した。同温度を保持したまま、得られた混合物に、式（Ｈ−１）で表される化合物１９９．１７部を、１時間かけて添加した後、更に、１０℃程度まで温度を上げ、同温度で１時間攪拌した。得られた反応混合物に、ｎ−へプタン１４４６．２２部及び２％塩酸水溶液７０３．４１部を加え、２３℃で３０分間攪拌した。静置、分液することにより回収された有機層に、２％塩酸水溶液３３７．６４部を仕込み、２３℃で３０分間攪拌した。静置、分液することにより有機層を回収した。回収された有機層に、イオン交換水３６１．５６部を仕込み２３℃で３０分間攪拌し、静置、分液することにより有機層を水洗した。回収された有機層に１０％炭酸カリウム水溶液４４３．９２部を仕込み、２３℃で３０分間攪拌し、静置、分液することにより有機層を洗浄した。このような洗浄操作を２回繰り返した。回収された有機層にイオン交換水３６１．５６部を仕込み、２３℃で３０分間攪拌、静置した後、分液することにより有機層を水洗した。このような水洗操作を５回繰り返した。回収された有機層を濃縮し、式（ａ４−１−７）で表される化合物１６３．６５部を得た。
ＭＳ（質量分析）：２７６．０（分子イオンピーク） Synthesis Example 1 [Synthesis of Compound Represented by Formula (a4-1-7)]

88.00 parts of the compound represented by the formula (H-2), 616.00 parts of methyl isobutyl ketone and 60.98 parts of pyridine were stirred and mixed at 23 ° C. for 30 minutes and cooled to 0 ° C. While maintaining the same temperature, 199.17 parts of the compound represented by formula (H-1) was added to the obtained mixture over 1 hour, and the temperature was further increased to about 10 ° C. For 1 hour. To the obtained reaction mixture, 1446.22 parts of n-heptane and 703.41 parts of 2% aqueous hydrochloric acid were added, and the mixture was stirred at 23 ° C. for 30 minutes. The organic layer recovered by standing and liquid separation was charged with 337.64 parts of 2% aqueous hydrochloric acid and stirred at 23 ° C. for 30 minutes. The organic layer was recovered by standing and liquid separation. To the recovered organic layer, 361.56 parts of ion-exchanged water was charged, stirred at 23 ° C. for 30 minutes, allowed to stand, and separated to wash the organic layer with water. The recovered organic layer was charged with 443.92 parts of 10% aqueous potassium carbonate solution, stirred at 23 ° C. for 30 minutes, allowed to stand, and separated to wash the organic layer. Such washing operation was repeated twice. 361.56 parts of ion-exchanged water was added to the collected organic layer, and the mixture was stirred and allowed to stand at 23 ° C. for 30 minutes, followed by liquid separation to wash the organic layer with water. Such washing operation was repeated 5 times. The collected organic layer was concentrated to obtain 163.65 parts of a compound represented by the formula (a4-1-7).
MS (mass spectrometry): 276.0 (molecular ion peak)

以下、これらのモノマーをその式番号に応じて、「モノマー（ａ１−１−２）」等という。 Resin Synthesis The compounds (monomers) used for resin synthesis are shown below.

Hereinafter, these monomers are referred to as “monomer (a1-1-2)” or the like according to the formula number.

Synthesis Example 2 [Synthesis of Resin A1-1]
As the monomer, the monomer (a1-1-2), the monomer (a1-2-3), the monomer (a2-1-1), the monomer (I1) and the monomer (a3-1-1) are used, and the molar ratio [ Monomer (a1-1-2): monomer (a1-2-3): monomer (a2-1-1): monomer (I1): monomer (a3-1-1)] is 20: 23: 3: 6 The mixture was mixed so as to be 48, and 1.5 mass times propylene glycol monomethyl ether acetate of the total monomer amount was added to prepare a 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 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol solvent to precipitate the resin, and the resin was filtered. The obtained resin was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol solvent to precipitate the resin, followed by two reprecipitation operations of filtering the resin, and a weight average molecular weight of 9. 2 × 10 ³ resin A1-1 was obtained with a yield of 73%. This resin A1-1 has the following structural units.

Synthesis Example 3 [Synthesis of Resin A1-2]
As the monomer, the monomer (a1-1-2), the monomer (a1-5-1), the monomer (a2-1-1), the monomer (I1) and the monomer (a3-1-1) are used, and the molar ratio [ Monomer (a1-1-2): monomer (a1-5-1): monomer (a2-1-1): monomer (I1): monomer (a3-1-1)] is 20: 23: 3: 6 The mixture was mixed so as to be 48, and 1.5 mass times propylene glycol monomethyl ether acetate of the total monomer amount was added to prepare a solution. To this solution, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 0.1 mol% and 3 mol%, respectively, based on the total amount of monomers, and these were heated at 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol solvent to precipitate the resin, and the resin was filtered. The resin obtained was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol solvent to precipitate the resin, followed by two reprecipitation operations of filtering the resin, and a weight average molecular weight of 8. 8 × 10 ³ resin A1-2 was obtained with a yield of 78%. This resin A1-2 has the following structural units.

Synthesis Example 4 [Synthesis of Resin A1-3]
As the monomer, monomer (a1-1-2), monomer (a1-2-3), monomer (a2-1-1), monomer (I1), monomer (a3-2-3) and monomer (a3-1- 1) and its molar ratio [monomer (a1-1-2): monomer (a1-2-3): monomer (a2-1-1): monomer (I1): monomer (a3-2-3): Monomer (a3-1-1)] is mixed so as to be 20: 23: 3: 6: 8: 40, and 1.5 mass times propylene glycol monomethyl ether acetate of the total monomer amount is added to obtain a solution. . 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to this solution, respectively, based on the total amount of monomers, and these were heated at 75 ° C. for about 5 hours. . The obtained reaction mixture was poured into a large amount of methanol solvent to precipitate the resin, and the resin was filtered. The obtained resin was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol solvent to precipitate the resin, followed by two reprecipitation operations of filtering the resin, and a weight average molecular weight of 9. 0 × 10 ³ resin A1-3 was obtained with a yield of 75%. This resin A1-3 has the following structural units.

Synthesis Example 5 [Synthesis of Resin A1-4]
As the monomer, the monomer (a1-1-3), the monomer (a1-2-9), the monomer (a2-1-3), the monomer (a3-2-3) and the monomer (I1) are used, and the molar ratio [ Monomer (a1-1-3): Monomer (a1-2-9): Monomer (a2-1-3): Monomer (a3-2-3): Monomer (I1)] is 45: 14: 2: 24: The resulting mixture was mixed with propylene glycol monomethyl ether acetate 1.5 times the total monomer amount to make a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to this solution, respectively, based on the total amount of monomers, and these were heated at 73 ° C. for about 5 hours. . The obtained reaction mixture was poured into a large amount of methanol / ion-exchanged water = 4/1 mixing solution to precipitate a resin, and the resin was filtered to obtain a resin A1-4 having a weight average molecular weight of 7.1 × 10 ³ . (Copolymer) was obtained with a yield of 63%. This resin A1-4 has the following structural units and was soluble in butyl acetate.

Synthesis Example 6 [Synthesis of Resin A1-5]
As the monomer, the monomer (a1-1-3), the monomer (a1-5-1), the monomer (a2-1-3), the monomer (a3-2-3) and the monomer (I1) are used, and the molar ratio [ Monomer (a1-1-3): Monomer (a1-5-1): Monomer (a2-1-3): Monomer (a3-2-3): Monomer (I1)] is 45: 14: 2: 24: The resulting mixture was mixed with propylene glycol monomethyl ether acetate 1.5 times the total monomer amount to make a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to this solution, respectively, based on the total amount of monomers, and these were heated at 73 ° C. for about 5 hours. . The obtained reaction mixture was poured into a large amount of methanol / ion-exchanged water = 4/1 mixing solution to precipitate a resin, and the resin was filtered to obtain a resin A1-5 having a weight average molecular weight of 7.0 × 10 ³ . (Copolymer) was obtained with a yield of 60%. This resin A1-5 has the following structural units and was soluble in butyl acetate.

Synthesis Example 7 [Synthesis of Resin A1-6]
As the monomer, monomer (a1-1-3), monomer (a1-2-9), monomer (a2-1-3) and monomer (I1) were used, and the molar ratio [monomer (a1-1-3): The monomer (a1-2-9): monomer (a2-1-3): monomer (I1)] is mixed so as to be 50: 14: 2: 34, and the propylene glycol is 1.5 mass times the total monomer amount. Monomethyl ether acetate was added to make a solution. 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to this solution, respectively, based on the total amount of monomers, and these were heated at 73 ° C. for about 5 hours. . The obtained reaction mixture was poured into a large amount of methanol / ion-exchanged water = 4/1 mixing solution to precipitate the resin, and the resin was filtered to obtain resin A1-6 (weight average molecular weight 7.3 × 10 ³ resin A1-6 ( Copolymer) was obtained in a yield of 60%. This resin A1-6 has the following structural units and was soluble in butyl acetate.

樹脂Ａ２−１ １ｇを酢酸ブチル１０ｇに添加して２３℃で攪拌した後、樹脂Ａ２−１が酢酸ブチルに溶解したことを目視で確認した。
同様にして、樹脂Ａ２−１が２−ヘプタノンに溶解したことを確認した。 Synthesis Example 8 [Synthesis of Resin A2-1]
Monomer (a4-1-7) was used as a monomer, and 1.5 mass times dioxane of the total monomer amount was added to prepare a solution. Azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the solution in an amount of 0.7 mol% and 2.1 mol%, respectively, with respect to the total monomer amount, and these were added at about 75 ° C. Heated for 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 was dissolved again in dioxane, and the solution obtained by pouring the solution into a methanol / water mixed solvent was precipitated twice, and the resin was filtered twice to perform the reprecipitation operation twice. 8 × 10 ⁴ resin A2-1 was obtained with a yield of 77%. This resin A2-1 has the following structural units.

After adding 1 g of resin A2-1 to 10 g of butyl acetate and stirring at 23 ° C., it was visually confirmed that the resin A2-1 was dissolved in butyl acetate.
Similarly, it was confirmed that Resin A2-1 was dissolved in 2-heptanone.

樹脂Ａ２−２ １ｇを酢酸ブチル１０ｇに添加して２３℃で攪拌した後、樹脂Ａ２−２が酢酸ブチルに溶解したことを目視で確認した。
同様にして、樹脂Ａ２−２が２−ヘプタノンに溶解したことを確認した。 Synthesis Example 9 [Synthesis of Resin A2-2]
Monomer (a4-z) was used as a monomer, and 4.0 mass times propylene glycol monomethyl ether acetate as a total monomer amount was added to prepare a solution. To the solution, 8 mol% of V-601 (manufactured by Wako Pure Chemical Industries) as an initiator was added with respect to the total amount of monomers, and these were heated at 80 ° C. 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 was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin. Resin A2-2 having an average molecular weight of 7.6 × 10 ³ was obtained with a yield of 70%. This resin A2-2 has the following structural units.

After adding 1 g of resin A2-2 to 10 g of butyl acetate and stirring at 23 ° C., it was visually confirmed that resin A2-2 was dissolved in butyl acetate.
Similarly, it was confirmed that Resin A2-2 was dissolved in 2-heptanone.

Synthesis Example 10 [Synthesis of Resin A3]
As the monomer, monomer (a1-z), monomer (a2-1-3), monomer (a3-2-1) and monomer (a5-z) are used, and the molar ratio [monomer (a1-z): monomer ( a2-1-3): monomer (a3-2-1): monomer (a5-z)] is mixed so as to be 30: 20: 40: 10, and the propylene is 1.5 mass times the total monomer amount. Glycol monomethyl ether acetate was added to make a 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 75 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol solvent to precipitate the resin, and the resin was filtered. The resin obtained was again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol solvent to precipitate the resin, followed by two reprecipitation operations of filtering the resin, and a weight average molecular weight of 8. 4 × 10 ³ resin A3 was obtained with a yield of 62%. This resin A3 has the following structural units.

式（Ｂ１−５−ａ）で表される塩５０．４９部及びクロロホルム２５２．４４部を反応器に仕込み、２３℃で３０分間攪拌した後、式（Ｂ１−５−ｂ）で表される化合物１６．２７部を滴下し、２３℃で１時間攪拌することにより、式（Ｂ１−５−ｃ）で表される塩を含む溶液を得た。得られた式（Ｂ１−５−ｃ）で表される塩を含む溶液に、式（Ｂ１−５−ｄ）で表される塩４８．８０部及びイオン交換水８４．１５部を添加し、２３℃で１２時間攪拌した。得られた反応液が２層に分離していたので、クロロホルム層を分液して取り出し、更に、該クロロホルム層にイオン交換水８４．１５部を添加し、水洗した。この操作を５回繰り返した。得られたクロロホルム層に、活性炭３．８８部を添加攪拌した後、ろ過した。回収されたろ液を濃縮し、得られた残渣に、アセトニトリル１２５．８７部を添加攪拌後、濃縮した。得られた残渣に、アセトニトリル２０．６２部及びｔｅｒｔ−ブチルメチルエーテル３０９．３０部を加えて２３℃で３０分間攪拌した後、上澄み液を除去した後、濃縮した。得られた残渣に、ｎ−ヘプタン２００部を添加、２３℃で３０分間攪拌した後、ろ過することにより、式（Ｂ１−５）で表される塩６１．５４部を得た。
ＭＡＳＳ（ＥＳＩ（＋）Ｓｐｅｃｔｒｕｍ）：Ｍ^＋ ３７５．２
ＭＡＳＳ（ＥＳＩ（−）Ｓｐｅｃｔｒｕｍ）：Ｍ⁻ ３３９．１ Synthesis Example 11 [Synthesis of salt represented by formula (B1-5)]

50.49 parts of the salt represented by the formula (B1-5-a) and 252.44 parts of chloroform are charged into a reactor, stirred at 23 ° C. for 30 minutes, and then represented by the formula (B1-5-b). 16.27 parts of the compound was added dropwise and stirred at 23 ° C. for 1 hour to obtain a solution containing a salt represented by the formula (B1-5-c). To the obtained solution containing the salt represented by the formula (B1-5-c), 48.80 parts of the salt represented by the formula (B1-5-d) and 84.15 parts of ion-exchanged water are added, The mixture was stirred at 23 ° C. for 12 hours. Since the resulting reaction solution was separated into two layers, the chloroform layer was separated and removed, and 84.15 parts of ion-exchanged water was further added to the chloroform layer and washed with water. This operation was repeated 5 times. To the obtained chloroform layer, 3.88 parts of activated carbon was added and stirred, followed by filtration. The collected filtrate was concentrated, 125.87 parts of acetonitrile was added to the resulting residue, and the mixture was stirred and concentrated. To the obtained residue, 20.62 parts of acetonitrile and 309.30 parts of tert-butyl methyl ether were added and stirred at 23 ° C. for 30 minutes, and then the supernatant was removed and concentrated. To the obtained residue, 200 parts of n-heptane was added, stirred at 23 ° C. for 30 minutes, and then filtered to obtain 61.54 parts of a salt represented by the formula (B1-5).
MASS (ESI (+) Spectrum): M ⁺ 375.2
MASS (ESI (−) Spectrum): M ^- 339.1

Synthesis Example 12 [Synthesis of Salt Represented by Formula (B1-21)]

  30.00 parts of a compound represented by the formula (B1-21-b) obtained by the method described in JP-A-2008-209917, and a salt 35.50 represented by the formula (B1-21-a). Part, 100 parts of chloroform, and 50 parts of ion-exchanged water were stirred at 23 ° C. for 15 hours. Since the obtained reaction solution was separated into two layers, the chloroform layer was separated and taken out, and 30 parts of ion-exchanged water was further added to the chloroform layer and washed with water. This operation was repeated 5 times. The chloroform layer was concentrated, 100 parts of tert-butyl methyl ether was added to the resulting residue, and the mixture was stirred at 23 ° C. for 30 minutes, and then filtered to obtain the salt 48 represented by the formula (B1-21-c). .57 parts were obtained.

式（Ｂ１−２１−ｃ）で表される塩２０．００部、式（Ｂ１−２１−ｄ）で表される化合物２．８４部及びモノクロロベンゼン２５０部を仕込み、２３℃で３０分間攪拌した。得られた混合液に、二安息香酸銅（ＩＩ）０．２１部を添加した後、更に、１００℃で１時間攪拌した。得られた反応溶液を濃縮した後、得られた残渣に、クロロホルム２００部及びイオン交換水５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。回収された有機層にイオン交換水５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。この水洗操作を５回繰り返した。得られた有機層を濃縮した後、得られた残渣に、アセトニトリル５３．５１部に溶解し、濃縮した後、ｔｅｒｔ−ブチルメチルエーテル１１３．０５部を加えて攪拌した後、ろ過することにより、式（Ｂ１−２１）で表される塩１０．４７部を得た。

20.00 parts of a salt represented by the formula (B1-21-c), 2.84 parts of a compound represented by the formula (B1-21-d) and 250 parts of monochlorobenzene were charged and stirred at 23 ° C. for 30 minutes. . After adding 0.21 part of copper (II) dibenzoate to the obtained liquid mixture, it stirred at 100 degreeC for further 1 hour. After concentrating the obtained reaction solution, 200 parts of chloroform and 50 parts of ion-exchanged water were added to the obtained residue and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out an organic layer. 50 parts of ion-exchanged water was added to the collected organic layer and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out the organic layer. This washing operation was repeated 5 times. After concentrating the obtained organic layer, the residue obtained was dissolved in 53.51 parts of acetonitrile, concentrated, 113.05 parts of tert-butyl methyl ether was added and stirred, and then filtered. 10.47 parts of the salt represented by the formula (B1-21) were obtained.

MASS (ESI (+) Spectrum): M ⁺ 237.1
MASS (ESI (−) Spectrum): M ^- 339.1

Synthesis Example 13 [Synthesis of salt represented by formula (B1-22)]

  11.26 parts of a salt represented by the formula (B1-22-a), 10.00 parts of a compound represented by the formula (B1-22-b), 50 parts of chloroform and 25 parts of ion-exchanged water were charged at 23 ° C. For 15 hours. Since the obtained reaction liquid was separated into two layers, the chloroform layer was separated and taken out, and further 15 parts of ion-exchanged water was added to the chloroform layer and washed with water. This operation was repeated 5 times. The chloroform layer was concentrated, 50 parts of tert-butyl methyl ether was added to the resulting residue, the mixture was stirred at 23 ° C. for 30 minutes, and then filtered to obtain the salt 11 represented by the formula (B1-22-c). .75 parts were obtained.

式（Ｂ１−２２−ｃ）で表される塩１１．７１部、式（Ｂ１−２２−ｄ）で表される化合物１．７０部及びモノクロロベンゼン４６．８４部を仕込み、２３℃で３０分間攪拌した。得られた混合液に、二安息香酸銅（ＩＩ）０．１２部を添加した後、更に、１００℃で３０分間攪拌した。得られた反応溶液を濃縮した後、得られた残渣に、クロロホルム５０部及びイオン交換水１２．５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。回収された有機層にイオン交換水１２．５０部を加えて２３℃で３０分間攪拌した後、分液して有機層を取り出した。この水洗操作を８回繰り返した。得られた有機層を濃縮した後、得られた残渣に、ｔｅｒｔ−ブチルメチルエーテル５０部を加えて攪拌した後、ろ過することにより、式（Ｂ１−２２）で表される塩６．８４部を得た。

11.71 parts of a salt represented by the formula (B1-22-c), 1.70 parts of a compound represented by the formula (B1-22-d) and 46.84 parts of monochlorobenzene were charged, and the mixture was charged at 23 ° C. for 30 minutes. Stir. After adding 0.12 part of copper (II) dibenzoate to the obtained liquid mixture, it stirred at 100 degreeC for 30 minutes further. After concentrating the obtained reaction solution, 50 parts of chloroform and 12.50 parts of ion-exchanged water were added to the obtained residue and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out an organic layer. 12.50 parts of ion-exchanged water was added to the collected organic layer and stirred at 23 ° C. for 30 minutes, followed by liquid separation to take out the organic layer. This washing operation was repeated 8 times. After concentration of the obtained organic layer, 50 parts of tert-butyl methyl ether was added to the obtained residue, stirred, and then filtered to obtain 6.84 parts of the salt represented by the formula (B1-22). Got.

MASS (ESI (+) Spectrum): M ⁺ 237.1
MASS (ESI (-) Spectrum): M ^- 323.0

<Preparation of resist composition>
Each component shown in Table 1 was mixed in the amount shown in Table 1 and dissolved in a solvent, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

Ｂ１−５：式（Ｂ１−５）で表される塩
Ｂ１−２１：式（Ｂ１−２１）で表される塩
Ｂ１−２２：式（Ｂ１−２２）で表される塩
Ｚ１：下記式で表される酸発生剤（和光純薬工業（株）製）

In the table, each symbol represents the following component.
<Resin>
A1-1: Resin A1-1
A1-2: Resin A1-2
A1-3: Resin A1-3
A1-4: Resin A1-4
A1-5: Resin A1-5
A1-6: Resin A1-6
A2-1: Resin A2-1
A2-2: Resin A2-2
A3: Resin A3
<Acid generator>
B1-3: An acid generator represented by the following formula. Synthesis according to examples of JP 2010-152341 A

B1-5: salt represented by formula (B1-5) B1-21: salt represented by formula (B1-21) B1-22: salt represented by formula (B1-22) Z1: Represented acid generator (Wako Pure Chemical Industries, Ltd.)

<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

Examples 1-13, Comparative Examples 1 and 2
<Manufacture of negative resist pattern>
An organic antireflective coating composition [ARC-29; manufactured by Nissan Chemical Industries, Ltd.] was applied onto a 12-inch silicon wafer, and baked under the conditions of 205 ° C. and 60 seconds, whereby an organic layer having a thickness of 78 nm. An antireflection film was formed. Next, the resist composition was spin-coated on the organic antireflection film so that the film thickness of the composition layer after drying (pre-baking) was 85 nm.
The silicon wafer coated with the resist composition was pre-baked on a direct hot plate at the temperature described in the “PB” column of Table 1 for 60 seconds to form a composition layer.
ArF excimer laser stepper for immersion exposure (XT: 1900 Gi; manufactured by ASML, NA = 1.35, 3/4 Annular XY polarized light) is used for the composition layer formed on the silicon wafer. The line-and-space pattern (pitch 100 nm / line width 50 nm) was subjected to immersion exposure while changing in steps from 5 to 50 mJ / cm ² . Note that ultrapure water was used as the immersion medium.
After the exposure, post-exposure baking was performed for 60 seconds on the hot plate at the temperature described in the “PEB” column of Table 1.
The composition layer after heating was subjected to dynamic dispense development at 23 ° C. for 20 seconds to dissolve the unexposed portion of the composition layer to produce a negative resist pattern. As a developer, n-butyl acetate manufactured by Tokyo Chemical Industry Co., Ltd. was used as it was without purification.

  In the obtained resist pattern, the exposure amount at which the line width and space width of the 50 nm line-and-space pattern were 1: 1 was defined as effective sensitivity.

<Line edge roughness evaluation (LER)>
The obtained resist pattern was observed with a scanning electron microscope, and the fluctuation width of the unevenness on the side wall of the resist pattern was measured. The results are shown in Table 2. The numbers indicate the fluctuation width (nm) of the unevenness on the side wall. The smaller the LER value, the smaller the unevenness on the side wall, and the better the resist pattern is.

Examples 14 to 26, Comparative Examples 3 and 4
Except for changing the developer to 2-heptanone (manufactured by Kyowa Hakko Co., Ltd.), the same operation as above was performed to produce a negative resist pattern, and the same evaluation as in Example 1 was performed. The results are shown in Table 3.

  From the above results, it can be seen that according to the method for producing a resist pattern of the present invention, a precise negative resist pattern having a small LER can be produced.

  According to the method for producing a resist pattern of the present invention, a precise negative resist pattern having a small LER can be produced, and thus it is extremely useful for fine processing of semiconductors.

Claims (8)

(1) a resin (A1) having a structural unit represented by formula (I) and a structural unit having an acid labile group,
A resin (A2) having a fluorine atom and soluble in a negative developer,
Applying a resist composition containing an acid generator and a solvent on a substrate;
(2) A step of drying the resist composition after coating to form a composition layer;
(3) exposing the composition layer;
(4) A step of heating the composition layer after exposure;
(5) A method for producing a resist pattern comprising a step of developing the heated composition layer with the negative developer,
A method for producing a resist pattern, wherein the negative developer is a developer containing at least one selected from the group consisting of butyl acetate and 2-heptanone.

[In the formula (I),
R ³ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
Ring ^{X 1} represents a heterocycle having 2 to 36 carbon atoms, a hydrogen atom contained in the heterocyclic ring, halogen atom, hydroxy group, a hydrocarbon group having 1 to 24 carbon atoms, an alkoxy group having 1 to 12 carbon atoms , May be substituted with an acyl group having 2 to 4 carbon atoms or an acyloxy group having 2 to 4 carbon atoms. ]   The method according to claim 1, wherein the step (5) is a step of developing the heated composition layer by a dynamic dispensing method.   The method according to claim 1 or 2, wherein the resin (A1) is a resin that is decomposed by the action of an acid and has reduced solubility in a negative developer. The resin (A2) is
The production method according to any one of claims 1 to 3, which is a resin comprising a structural unit represented by the formula (a4-1).

[In the formula (a4-1),
R ^a41 represents a monovalent hydrocarbon group having 1 to 12 carbon atoms, and the methylene group constituting the hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
A ^a41 is an alkanediyl group having 1 to 6 carbon atoms which may have a substituent or a formula (a-g1).

(In the formula (a-g1), s represents 0 or 1.
A ^a42 and A ^a44 each independently represent an ^optionally substituted aliphatic hydrocarbon group having 1 to 5 carbon atoms.
A ^a43 represents an aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent or a single bond.
X ^a41 and X ^a42 each independently represent an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group.
However, the total number of carbon atoms of A ^a42 , A ^a43 , A ^a44 , X ^a41 and X ^a42 is 7 or less. )
Represents a group represented by
R ^a42 represents a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, the methylene group of which may be substituted with a carbonyloxy group or an oxycarbonyl group.
However, at least one of A ^a41 and R ^a42 is a group having a fluorine atom. ]   The manufacturing method according to claim 4, wherein the resin (A2) is a resin further having a structural unit containing an alicyclic hydrocarbon group.   Content of the said resin (A2) is 1-60 mass parts with respect to 100 mass parts of said resin (A1), The manufacturing method as described in any one of Claims 1-5. The said acid generator is an acid generator represented by Formula (B1), The manufacturing method as described in any one of Claims 1-6.

[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 an aliphatic saturated hydrocarbon group having 1 to 24 carbon atoms, and the hydrogen atom contained in the aliphatic saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group, and the aliphatic saturated carbon group The methylene group constituting the hydrogen group may be replaced with an oxygen atom or a carbonyl group.
Y represents a hydrogen atom, a fluorine atom or a C3-C18 alicyclic hydrocarbon group which may have a substituent, and the methylene group constituting the alicyclic hydrocarbon group is an oxygen atom, A sulfonyl group or a carbonyl group may be substituted.
Z ⁺ represents an organic cation. ] The production method according to claim 7, wherein Y is an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent .