JP7353193B2 - Resist pattern formation method - Google Patents

Description

The present invention relates to a resist pattern forming method.

In lithography technology, for example, a resist film made of a resist material is formed on a substrate, and the resist film is selectively exposed and developed to form a resist pattern of a predetermined shape on the resist film. The process of A resist material whose characteristics change so that the exposed portion of the resist film dissolves in a developer is called a positive type, and a resist material whose characteristics change so that the exposed portion of the resist film does not dissolve in a developer is called a negative type.
In recent years, in the manufacture of semiconductor devices and liquid crystal display devices, advances in lithography technology have led to rapid miniaturization of patterns. As a technique for miniaturization, generally the wavelength of the exposure light source is shortened (the energy is increased). Specifically, in the past, ultraviolet rays such as g-line and i-line were used, but now semiconductor devices are mass-produced using KrF excimer lasers and ArF excimer lasers. Further, studies are also being conducted on EUV (extreme ultraviolet), EB (electron beam), X-rays, etc., which have shorter wavelengths (higher energy) than these excimer lasers.

Resist materials are required to have lithography properties such as sensitivity to these exposure light sources and resolution capable of reproducing patterns with minute dimensions.
As a resist material that satisfies these requirements, chemically amplified resist compositions have conventionally been used that contain a base component whose solubility in a developer changes due to the action of an acid, and an acid generator component that generates an acid upon exposure. is used.
For example, when the above developer is an alkaline developer (alkaline development process), a positive chemically amplified resist composition consists of a resin component (base resin) whose solubility in the alkaline developer increases due to the action of acid, Those containing the following ingredients are generally used. When a resist film formed using such a resist composition is selectively exposed during resist pattern formation, acid is generated from the acid generator component in the exposed area, and the polarity of the base resin increases due to the action of the acid. As a result, the exposed portion of the resist film becomes soluble in the alkaline developer. Therefore, by alkali development, a positive pattern is formed in which the unexposed portions of the resist film remain as a pattern.
On the other hand, when such a chemically amplified resist composition is applied to a solvent development process using a developer containing an organic solvent (organic developer), as the polarity of the base resin increases, the organic developer Since the solubility in the liquid decreases, the unexposed portions of the resist film are dissolved and removed by the organic developer, forming a negative resist pattern in which the exposed portions of the resist film remain as a pattern. A solvent development process for forming a negative resist pattern in this manner is sometimes referred to as a negative development process.

A base resin used in a chemically amplified resist composition generally has a plurality of structural units in order to improve lithography properties and the like.
For example, in the case of a resin component whose solubility in an alkaline developer increases due to the action of an acid, a structural unit containing an acid-decomposable group whose polarity increases when decomposed by the action of an acid generated from an acid generator or the like is used. In addition, a structural unit containing a lactone-containing cyclic group, a structural unit containing a polar group such as a hydroxyl group, etc. are used in combination.

A wide variety of acid generator components have been proposed for use in chemically amplified resist compositions. For example, onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, diazomethane acid generators, nitrobenzyl sulfonate acid generators, iminosulfonate acid generators, disulfone acid generators, etc. It has been known.
As onium salt acid generators, those having an onium ion such as triphenylsulfonium in the cation moiety are mainly used. The anion moiety of onium salt-based acid generators generally uses an alkyl sulfonate ion or a fluorinated alkyl sulfonate ion in which some or all of the hydrogen atoms of the alkyl group are replaced with fluorine atoms. .

In forming a resist pattern, the behavior of the acid generated from the acid generator component upon exposure is considered to be one factor that greatly influences the lithography characteristics.
Particularly when exposing to EUV (extreme ultraviolet) or EB (electron beam), acid diffusion controllability becomes a problem in resist materials. In order to control acid diffusion, various methods of changing the design of polymer compounds have been proposed.
For example, resist compositions have been disclosed that employ polymeric compounds having specific acid-dissociable functional groups to improve reactivity to acids and improve solubility in developing solutions (for example, , see Patent Documents 1 and 2).

Japanese Patent Application Publication No. 2009-114381 Japanese Patent Application Publication No. 2012-220800

With further progress in lithography technology and miniaturization of resist patterns, the goal of lithography using EUV or EB, for example, is to form fine patterns of several tens of nanometers. As the resist pattern size becomes smaller, the resist composition is required to have higher sensitivity to the exposure light source and better lithography properties such as reduced roughness.
However, in the conventional resist compositions as described above, when increasing the sensitivity to an exposure light source such as EUV, it becomes difficult to obtain a desired resist pattern shape, etc., and it is difficult to satisfy all of these characteristics. was difficult.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resist pattern forming method with good lithography characteristics.

In forming a resist pattern, especially when exposing a resist film to EUV or EB, it has a structural unit containing a hydroxystyrene skeleton and a structural unit containing an acid-decomposable group that decomposes under the action of an acid and increases in polarity. Polymeric compounds are useful.
However, the present inventors have investigated and found that when forming a resist pattern using EUV or EB as an exposure light source, the polymer compound obtained by random copolymerization of monomers using a conventional radical polymerization method. It has been confirmed that when using a resist composition, there is a problem in that lithography properties tend to be adversely affected.
On the other hand, by copolymerizing a structural unit whose hydroxystyrene skeleton is protected with a protecting group that can be deprotected with an acid component and a structural unit having a specific imide structure, and then hydrolyzing it, each protecting group can be removed. The present inventors have discovered that lithography properties can be improved by employing a polymer compound obtained by deprotection, and have completed the present invention.

That is, the first aspect of the present invention is to copolymerize a compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) by living radical polymerization. , a step of obtaining an alternating copolymer represented by the following general formula (p0), and a first polymer compound precursor represented by the following general formula (Pre-1a) by hydrolyzing the alternating copolymer. The first polymer compound precursor is reacted with a compound represented by the following general formula (Add-1) to obtain a compound represented by the following general formula (Pre-1b-1). a step of obtaining a second polymer compound precursor, and a step of hydrolyzing the second polymer compound precursor to obtain a polymer compound (A01) represented by the following general formula (p1); A step of preparing a resist composition by mixing the polymer compound (A01) and an organic solvent, a step of forming a resist film on a support using the resist composition, and exposing the resist film to light. This is a method for forming a resist pattern, which includes a step of developing the exposed resist film to form a resist pattern.

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０２及びＲｐ^０３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒｐ^０２及びＲｐ^０３は、相互に結合して環を形成していてもよい。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。Ｒａ^００１、Ｒａ^００２及びＲａ^００３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒａ^００２及びＲａ^００３は、相互に結合して環を形成していてもよい。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. ]

［式中、Ｒｐ^０１及びＲｐ^０４は、それぞれ独立に水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒａ^００１、Ｒａ^００２及びＲａ^００３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒａ^００２及びＲａ^００３は、相互に結合して環を形成していてもよい。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ and Rp ⁰⁴ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. ]

A second aspect of the present invention is to copolymerize a compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) by living radical polymerization, and A step of obtaining an alternating copolymer represented by the general formula (p0), and hydrolyzing the alternating copolymer to obtain a first polymer compound precursor represented by the following general formula (Pre-2a). A step of reacting the first polymer compound precursor with a compound represented by the following general formula (Add-1) to obtain a polymer compound (A01) represented by the following general formula (p1). ), a step of mixing the polymer compound (A01) and an organic solvent to prepare a resist composition, and a step of forming a resist film on a support using the resist composition. , a resist pattern forming method including the steps of exposing the resist film, and developing the exposed resist film to form a resist pattern.

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０２及びＲｐ^０３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒｐ^０２及びＲｐ^０３は、相互に結合して環を形成していてもよい。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。ｎ_１は０～４の整数である。Ｒａ^００１、Ｒａ^００２及びＲａ^００３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒａ^００２及びＲａ^００３は、相互に結合して環を形成していてもよい。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. ]

A third aspect of the present invention is to copolymerize a compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) by living radical polymerization, and A step of obtaining an alternating copolymer represented by the general formula (p0), and hydrolyzing the alternating copolymer to obtain a first polymer compound precursor represented by the following general formula (Pre-1a). and a step of reacting the first polymer compound precursor with a compound represented by the following general formula (Add-2) to obtain a compound represented by the following general formula (Pre-1b-2). a step of obtaining a polymer compound precursor of No. 2; a step of hydrolyzing the second polymer compound precursor to obtain a polymer compound (A02) represented by the following general formula (p2); A step of preparing a resist composition by mixing a molecular compound (A02) and an organic solvent, a step of forming a resist film on a support using the resist composition, and a step of exposing the resist film. and a step of developing the exposed resist film to form a resist pattern.

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０２及びＲｐ^０３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒｐ^０２及びＲｐ^０３は、相互に結合して環を形成していてもよい。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。Ｒａ^００４、Ｒａ^００５は水素原子又はアルキル基である。Ｒａ^００６は炭化水素基であって、Ｒａ^００６は、Ｒａ^００４、Ｒａ^００５のいずれかと結合して環を形成してもよい。Ｘは、ハロゲン原子である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. Ra ⁰⁰⁴ and Ra ⁰⁰⁵ are hydrogen atoms or alkyl groups. Ra ⁰⁰⁶ is a hydrocarbon group, and Ra ⁰⁰⁶ may be combined with either Ra ⁰⁰⁴ or Ra ⁰⁰⁵ to form a ring. X is a halogen atom. ]

［式中、Ｒｐ^０１及びＲｐ^０４は、それぞれ独立に水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒａ^００４、Ｒａ^００５は水素原子又はアルキル基である。Ｒａ^００６は炭化水素基であって、Ｒａ^００６は、Ｒａ^００４、Ｒａ^００５のいずれかと結合して環を形成してもよい。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ and Rp ⁰⁴ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Ra ⁰⁰⁴ and Ra ⁰⁰⁵ are hydrogen atoms or alkyl groups. Ra ⁰⁰⁶ is a hydrocarbon group, and Ra ⁰⁰⁶ may be combined with either Ra ⁰⁰⁴ or Ra ⁰⁰⁵ to form a ring. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. ]

A fourth aspect of the present invention is to copolymerize a compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) by living radical polymerization, and A step of obtaining an alternating copolymer represented by the general formula (p0), and hydrolyzing the alternating copolymer to obtain a first polymer compound precursor represented by the following general formula (Pre-2a). A step of reacting the first polymer compound precursor with a compound represented by the following general formula (Add-2) to obtain a polymer compound (A02) represented by the following general formula (p2). ), a step of preparing a resist composition by mixing the polymer compound (A02) and an organic solvent, and a step of forming a resist film on a support using the resist composition. , a resist pattern forming method including the steps of exposing the resist film, and developing the exposed resist film to form a resist pattern.

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０２及びＲｐ^０３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒｐ^０２及びＲｐ^０３は、相互に結合して環を形成していてもよい。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。ｎ_１は０～４の整数である。Ｒａ^００４、Ｒａ^００５は水素原子又はアルキル基である。Ｒａ^００６は炭化水素基であって、Ｒａ^００６は、Ｒａ^００４、Ｒａ^００５のいずれかと結合して環を形成してもよい。Ｘは、ハロゲン原子である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. Ra ⁰⁰⁴ and Ra ⁰⁰⁵ are hydrogen atoms or alkyl groups. Ra ⁰⁰⁶ is a hydrocarbon group, and Ra ⁰⁰⁶ may be combined with either Ra ⁰⁰⁴ or Ra ⁰⁰⁵ to form a ring. X is a halogen atom. ]

According to the resist pattern forming method of the present invention, a resist pattern forming method with good lithography characteristics can be provided.

In this specification and the claims, the term "aliphatic" is a relative concept to aromatic, and is defined to mean groups, compounds, etc. that do not have aromaticity.
Unless otherwise specified, "alkyl group" includes linear, branched, and cyclic monovalent saturated hydrocarbon groups. The same applies to the alkyl group in the alkoxy group.
Unless otherwise specified, the "alkylene group" includes linear, branched, and cyclic divalent saturated hydrocarbon groups.
Examples of the "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
"Constituent unit" means a monomer unit (monomer unit) that constitutes a high molecular compound (resin, polymer, copolymer).
When describing "may have a substituent", there are cases in which a hydrogen atom (-H) is substituted with a monovalent group and a case in which a methylene group (-CH ₂ -) is substituted with a divalent group. including both.
“Exposure” is a concept that includes radiation irradiation in general.

An "acid-decomposable group" is a group having acid-decomposability that allows at least a portion of the bonds in the structure of the acid-decomposable group to be cleaved by the action of an acid.
Examples of acid-decomposable groups whose polarity increases due to the action of an acid include groups that decompose under the action of an acid to produce a polar group.
Examples of the polar group include a carboxy group, a hydroxyl group, an amino group, and a sulfo group (-SO ₃ H).
More specifically, the acid-decomposable group includes a group in which the polar group is protected with an acid-dissociable group (for example, a group in which the hydrogen atom of an OH-containing polar group is protected with an acid-dissociable group).

"Acid-dissociable group" refers to (i) a group having acid-dissociable properties that allows the bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group to be cleaved by the action of an acid; (ii) A group in which the bond between the acid-dissociable group and the atom adjacent to the acid-dissociable group can be cleaved by further decarboxylation reaction after some bonds are cleaved by the action of an acid. , refers to both.
The acid-dissociable group constituting the acid-dissociable group needs to be a group with lower polarity than the polar group generated by dissociation of the acid-dissociable group. When is dissociated, a polar group having higher polarity than the acid-dissociable group is generated and the polarity increases. As a result, the polarity of the entire component (A1) increases. As the polarity increases, the relative solubility in the developer changes; when the developer is an alkaline developer, the solubility increases, and when the developer is an organic developer, the solubility decreases. Decrease.

The "base material component" is an organic compound that has film-forming ability. Organic compounds used as base material components are broadly classified into non-polymers and polymers. As the non-polymer, those having a molecular weight of 500 or more and less than 4,000 are usually used. Hereinafter, the term "low molecular compound" refers to a non-polymer having a molecular weight of 500 or more and less than 4,000. As the polymer, one having a molecular weight of 1000 or more is usually used. Hereinafter, "resin", "high molecular compound", or "polymer" refers to a polymer having a molecular weight of 1000 or more. As the molecular weight of the polymer, the weight average molecular weight calculated by GPC (gel permeation chromatography) in terms of polystyrene is used.

"Derived structural unit" means a structural unit formed by cleavage of multiple bonds between carbon atoms, for example, ethylenic double bonds.
In the "acrylic ester", the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent. The substituent (R ^αx ) that substitutes the hydrogen atom bonded to the α-position carbon atom is an atom or group other than a hydrogen atom. In addition, there are also itaconic acid diesters in which the substituent (R ^αx ) is substituted with a substituent containing an ester bond, and α-hydroxyacrylic esters in which the substituent (R ^αx ) is substituted with a hydroxyalkyl group or a group modifying the hydroxyl group. shall be included. Note that the carbon atom at the α-position of the acrylic ester is the carbon atom to which the carbonyl group of acrylic acid is bonded, unless otherwise specified.
Hereinafter, an acrylic ester in which the hydrogen atom bonded to the carbon atom at the α-position is substituted with a substituent may be referred to as an α-substituted acrylic ester.

The term "derivative" is a concept that includes target compounds in which the hydrogen atom at the α-position is substituted with other substituents such as alkyl groups and halogenated alkyl groups, as well as derivatives thereof. These derivatives include those in which the hydrogen atom of the hydroxyl group of the target compound is replaced with an organic group; the hydrogen atom at the α position may be substituted with a substituent; Good target compounds include those to which a substituent other than a hydroxyl group is bonded. Note that the α-position refers to the first carbon atom adjacent to a functional group, unless otherwise specified.
Examples of the substituent for substituting the hydrogen atom at the α-position of hydroxystyrene include those similar to R ^αx .

In this specification and the claims, some structures represented by chemical formulas may contain asymmetric carbon atoms and may have enantiomers or diastereomers. In that case, one chemical formula represents these isomers. These isomers may be used alone or as a mixture.

(Resist pattern formation method)
(First aspect)
The resist pattern forming method according to the first aspect of the present invention includes:
(ia) A compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) are copolymerized by living radical polymerization to form the following general formula (p0). A step of obtaining the represented alternating copolymer (hereinafter also referred to as step (ia)),
(IIA) Hydrolyzing the alternating copolymer to obtain a first polymer compound precursor represented by the following general formula (Pre-1a) (hereinafter also referred to as step (IIA));
(iiiia) The first polymer compound precursor and the compound represented by the following general formula (Add-1) are reacted to form a second polymer compound represented by the following general formula (Pre-1b-1). a step of obtaining a polymer compound precursor;
(iva) a step of hydrolyzing the second polymer compound precursor to obtain a polymer compound (A01) represented by the following general formula (p1) (hereinafter also referred to as step (iva));
(va) a step of preparing a resist composition by mixing the polymer compound (A01) and an organic solvent (hereinafter also referred to as step (va));
(via) forming a resist film on the support using the resist composition (hereinafter also referred to as step (via));
(viia) A resist pattern forming method including the steps of exposing the resist film to light, and developing the exposed resist film to form a resist pattern (hereinafter also referred to as step (viia)).

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０２及びＲｐ^０３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒｐ^０２及びＲｐ^０３は、相互に結合して環を形成していてもよい。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。Ｒａ^００１、Ｒａ^００２及びＲａ^００３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒａ^００２及びＲａ^００３は、相互に結合して環を形成していてもよい。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. ]

［式中、Ｒｐ^０１及びＲｐ^０４は、それぞれ独立に水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒａ^００１、Ｒａ^００２及びＲａ^００３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒａ^００２及びＲａ^００３は、相互に結合して環を形成していてもよい。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ and Rp ⁰⁴ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. ]

<Process (ia)>
In step (ia), a compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) are copolymerized by living radical polymerization to form the following general formula ( This is a step of obtaining an alternating copolymer represented by p0).

≪Living radical polymerization≫
Living radical polymerization is a polymerization reaction in which the termination reaction is suppressed to some extent by the equilibrium between the dormant species and the radical growth species, and the molecular weight can be controlled by a reversible exchange reaction. It is believed that when the exchange reaction occurs much faster than the polymerization reaction, a polymer with a narrow molecular weight distribution is obtained.
Examples of living radical polymerization include those using chain transfer agents such as polysulfides, radical scavengers such as cobalt porphyrin complexes and nitroxide compounds, and atomic transfer using organic halogen compounds as initiators and transition metal complexes as catalysts. Examples include radical polymerization. Among these, atom transfer radical polymerization is preferred.

- Atom transfer radical polymerization As the organic halogen compound in the atom transfer radical polymerization, α-halogenocarbonyl compounds, α-halogenocarboxylic acid esters, etc. can be used. Among these, α-halogenocarboxylic acid esters are preferred, and specific examples thereof include ethyl 2-bromo-2-methylpropanoate, 2-hydroxyethyl 2-bromopropionate, and 2-chloro-2,4,4-trimethylglutaric acid. Examples include dimethyl, ethyl 2-chloro-2-phenylacetate, and ethyl 2-chloro-2-phenylacetate is more preferred.

The central metals constituting the transition metal complex in the atom transfer radical polymerization include elements from groups 7 to 11 of the periodic table, such as iron, copper, nickel, rhodium, ruthenium, and rhenium (Chemical Handbook Basics I, edited by the Chemical Society of Japan). According to the periodic table described in "Revised 4th Edition" (1993)) is preferably mentioned. Among them, ruthenium and copper are more preferable.

Specific examples of transition metal complexes containing ruthenium as a central metal include dichlorotris(triphenylphosphine)ruthenium, dichlorotris(tributylphosphine)ruthenium, dichloro(cyclooctadiene)ruthenium, dichlorobenzeneruthenium, dichlorop-cymeneruthenium, Dichloro(norbornadiene)ruthenium, cis-dichlorobis(2,2'-bipyridine)ruthenium, dichlorotris(1,10-phenanthroline)ruthenium, carbonylchlorohydridotris(triphenylphosphine)ruthenium, chlorocyclopentadienylbis(triphenyl) phosphine)ruthenium, chloropentamethylcyclopentadienylbis(triphenylphosphine)ruthenium, chloroindenylbis(triphenylphosphine)ruthenium, and the like. Among them, dichlorotris(triphenylphosphine)ruthenium, chloropentamethylcyclopentadienylbis(triphenylphosphine)ruthenium (RuCp ^* catalyst), and chloroindenylbis(triphenylphosphine)ruthenium are preferred; Dienylbis(triphenylphosphine)ruthenium (RuCp ^* catalyst) is more preferred.

In the atom transfer radical polymerization, a Lewis acid or an amine may be used as a cocatalyst.
Examples of Lewis acids include aluminum trialkoxides such as aluminum triisopropoxide and aluminum tri(t-butoxide); bis(2,6-di-t-butylphenoxy)methylaluminum, bis(2,4,6-tri-butoxide); Bis(substituted aryloxy)alkylaluminum such as t-butylphenoxy)methylaluminum; tris(substituted aryloxy)aluminum such as tris(2,6-diphenylphenoxy)aluminum; titanium tetraalkoxide such as titanium tetraisopropoxide, etc. Can be mentioned. Among these, aluminum trialkoxide is preferred, and aluminum triisopropoxide is more preferred.

Examples of amines include aliphatic primary amines such as methylamine, ethylamine, propylamine, isopropylamine, and butylamine; aliphatic secondary amines such as dimethylamine, diethylamine, dipropylamine, diisopropylamine, and dibutylamine; trimethylamine, Aliphatic amines such as aliphatic tertiary amines such as triethylamine, tripropylamine, triisopropylamine, tributylamine; N,N,N',N'-tetramethylethylenediamine, N,N,N',N'' , N''-pentamethyldiethylenetriamine, aliphatic polyamines such as 1,1,4,7,10,10-hexamethyltriethylenetetraamine; aromatic primary amines such as aniline and toluidine; aromatic such as diphenylamine; Secondary amines include aromatic amines such as aromatic tertiary amines such as triphenylamine. Among these, aliphatic amines are preferred, and specifically, butylamine, dibutylamine, and tributylamine are more preferred.

Examples of the solvent used in the atom transfer radical polymerization include esters such as ethyl acetate, butyl acetate, ethyl lactate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and cellosolves; alkyl lactones such as γ-butyrolactone. ; Ethers such as tetrahydrofuran, dimethoxyethane, and diethoxyethane; Alkyl ketones such as 2-butanone (methyl ethyl ketone), 2-heptanone, and methyl isobutyl ketone; cycloalkyl ketones such as cyclohexanone; 2-propanol, propylene glycol monomethyl ether , alcohols such as isopropyl alcohol; hydrocarbons such as heptane, cyclohexane, cycloheptane, toluene, xylene; aprotic polar solvents such as dimethylformamide (DMF), dimethylsulfoxide, dimethylacetamide, hexamethylphosphoramide; dichloromethane , dichloroethane, chloroform, and other nonpolar solvents.
These solvents can be used alone or in combination of two or more.

The reaction temperature in the atom transfer radical polymerization is usually 40 to 150°C, preferably 50 to 130°C.
The reaction time in the atom transfer radical polymerization is usually 1 to 96 hours, preferably 1 to 48 hours.

≪Compound (m0-1)≫
Compound (m0-1) is a compound represented by the following general formula (m0-1).

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０２及びＲｐ^０３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒｐ^０２及びＲｐ^０３は、相互に結合して環を形成していてもよい。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. ]

In the above formula (m0-1), Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms.
The alkyl group having 1 to 5 carbon atoms in Rp ⁰¹ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, methyl group, ethyl group, propyl group, isopropyl group, Examples include n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, and the like.
The halogenated alkyl group having 1 to 5 carbon atoms in Rp ⁰¹ is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like, with a fluorine atom being particularly preferred.
Rp ⁰¹ is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and most preferably a hydrogen atom or a methyl group from the viewpoint of industrial availability.

In the above formula (m0-1), Vp ⁰¹ is a single bond or a divalent linking group.
Suitable examples of the divalent linking group in Vp ⁰¹ include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom.

・Divalent hydrocarbon group that may have a substituent:
When Vp ⁰¹ is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

...Aliphatic hydrocarbon group in Vp ⁰¹ The aliphatic hydrocarbon group means a hydrocarbon group without aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, and the like.

...Linear or branched aliphatic hydrocarbon group The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and The number of carbon atoms is more preferably 1 to 4, and the number of carbon atoms is most preferably 1 to 3.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH ₂ -], an ethylene group [-(CH ₂ ) ₂ -], a trimethylene group [ -(CH ₂ ) ₃ -], tetramethylene group [-(CH ₂ ) ₄ -], pentamethylene group [-(CH ₂ ) ₅ -], and the like.
The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ - and other alkylmethylene groups; CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ )CH ₂ -, -C(CH ₂ Alkylethylene groups such as CH ₃ ) ₂ -CH ₂ -; -CH(CH ₃ )CH ₂ CH ₂ -, alkyltrimethylene groups such as -CH ₂ CH(CH ₃ )CH ₂ -; -CH(CH ₃ ) Examples include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ )CH ₂ CH ₂ -, and the like. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and a carbonyl group.

...Aliphatic hydrocarbon group containing a ring in its structure The aliphatic hydrocarbon group containing a ring in its structure is a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in its ring structure. (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, Examples include groups in which a group hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those mentioned above.
The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms. Specifically, Examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and a carbonyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, or tert-butoxy group. Most preferred are methoxy and ethoxy groups.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like, with a fluorine atom being preferred.
Examples of the halogenated alkyl group as the substituent include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms.
In the cyclic aliphatic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a substituent containing a heteroatom. As the substituent containing the hetero atom, -O-, -C(=O)-O-, -S-, -S(=O) ₂ -, and -S(=O) ₂ -O- are preferable.

...Aromatic hydrocarbon group in Vp ⁰¹ The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, even more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in substituents. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; Can be mentioned. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, the aromatic hydrocarbon group includes a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); an aromatic compound containing two or more aromatic rings; (e.g. biphenyl, fluorene, etc.) with two hydrogen atoms removed; One hydrogen atom of the group (aryl group or heteroaryl group) obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle. is substituted with an alkylene group. (a group in which one atom is removed), and the like. The alkylene group bonded to the aryl group or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon number.

The hydrogen atom of the aromatic hydrocarbon group may be substituted with a substituent. For example, the hydrogen atom bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group.
Examples of the alkoxy group, halogen atom, and halogenated alkyl group as the substituent include those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

・Divalent linking group containing a heteroatom:
When Vp ⁰¹ is a divalent linking group containing a heteroatom, the linking group is preferably -O-, -C(=O)-O-, -C(=O)-, -O-C (=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)-(H may be substituted with a substituent such as an alkyl group or an acyl group) ), -S-, -S(=O) ₂ -, -S(=O) ₂ -O-, general formula -Y ²¹ -O-Y ²² -, -Y ²¹ -O-, -Y ²¹ - C(=O)-O-, -C(=O)-O-Y ²¹ -, -[Y ²¹ -C(=O)-O] _m” -Y ²² -, -Y ²¹ -O-C( A group represented by =O)-Y ²² - or -Y ²¹ -S(=O) ₂ -O-Y ²² - [wherein Y ²¹ and Y ²² each independently have a substituent] O is an oxygen atom, and m'' is an integer from 0 to 3. ] etc.
The above divalent linking group containing a hetero atom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=NH )-, H may be substituted with a substituent such as an alkyl group or an acyl group. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
General formula -Y ²¹ -O-Y ²² -, -Y ²¹ -O-, -Y ²¹ -C(=O)-O-, -C(=O)-O-Y ²¹ -, -[Y ²¹ - C(=O)-O] _m” -Y ²² -, -Y ²¹ -O-C(=O)-Y ²² - or -Y ²¹ -S(=O) ₂ -O-Y ²² -, Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group include those mentioned in the description of the divalent linking group above. (divalent hydrocarbon group which may have a substituent).
^Y21 is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, even more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly a methylene group or an ethylene group. preferable.
Y ²² is preferably a linear or branched aliphatic hydrocarbon group, more preferably a methylene group, ethylene group or alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
In the group represented by the formula -[Y ²¹ -C(=O)-O] _m" -Y ²² -, m" is an integer of 0 to 3, preferably an integer of 0 to 2, and 0 or 1 is more preferred, and 1 is particularly preferred. In other words, as a group represented by the formula -[Y ²¹ -C(=O)-O] _m'' -Y ²² -, a group represented by the formula -Y ²¹ -C(=O)-O-Y ²² - Groups are particularly preferred. Among these, groups represented by the formula -(CH ₂ ) _a' -C(=O)-O-(CH ₂ ) _b' - are preferred. In the formula, a' is 1 to 10 b' is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, even more preferably 1 or 2, and most preferably 1.b' is an integer of 1 to 10, and An integer is preferred, an integer from 1 to 5 is more preferred, 1 or 2 is even more preferred, and 1 is most preferred.

In the above formula (m0-1), Vp ⁰¹ is a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), -C(=O)-NH -, a linear or branched alkylene group, or a combination thereof, and a single bond is more preferred.

In the above formula (m0-1), Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. The hydrocarbon groups in Rp ⁰² and Rp ⁰³ may each be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a cyclic hydrocarbon group, or a chain hydrocarbon group.

Cyclic group that may have a substituent:
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. Aliphatic hydrocarbon group means a hydrocarbon group without aromaticity. Further, the aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated. Furthermore, the cyclic hydrocarbon group in Rp ⁰² and Rp ⁰³ may contain a heteroatom such as a heterocycle.

The aromatic hydrocarbon group in Rp ⁰² and Rp ⁰³ is a hydrocarbon group having an aromatic ring.
Specifically, the aromatic rings possessed by the aromatic hydrocarbon groups in Rp ⁰² and Rp ⁰³ include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or those in which some of the carbon atoms constituting these aromatic rings are heteroatoms. Examples include substituted aromatic heterocycles. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, the aromatic hydrocarbon groups in Rp ⁰² and Rp ⁰³ include a group obtained by removing one hydrogen atom from the aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.), a group obtained by removing one hydrogen atom from the aromatic ring, and a group obtained by removing one hydrogen atom from the aromatic ring. A group in which one of the groups is substituted with an alkylene group (for example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc.), etc. Can be mentioned.

Examples of the cyclic aliphatic hydrocarbon group in Rp ⁰² and Rp ⁰³ include an aliphatic hydrocarbon group containing a ring in the structure.
The aliphatic hydrocarbon group containing a ring in its structure includes an alicyclic hydrocarbon group (a group in which one hydrogen atom is removed from an aliphatic hydrocarbon ring), and an alicyclic hydrocarbon group that is linear or branched. Examples thereof include a group bonded to the end of a chain aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group.
The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. Examples of the monocyclic alicyclic hydrocarbon group include a group obtained by removing one or more hydrogen atoms from a monocycloalkane. Specific examples include cyclopentane and cyclohexane.
Examples of the polycyclic alicyclic hydrocarbon group include a group obtained by removing one or more hydrogen atoms from a polycycloalkane. Specifically, the polycycloalkanes include polycycloalkanes having a polycyclic skeleton of a bridged ring system such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane; cyclic groups having a steroid skeleton; Examples include polycycloalkanes having a polycyclic skeleton of a fused ring system.

Examples of substituents on the cyclic groups of Rp ⁰² and Rp ⁰³ include alkyl groups, alkoxy groups, halogen atoms, halogenated alkyl groups, hydroxyl groups, nitro groups, and carbonyl groups.

Chain-like alkyl group which may have a substituent:
The chain alkyl groups of Rp ⁰² and Rp ⁰³ may be either linear or branched.
Specific examples of linear alkyl groups include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, undecyl group, dodecyl group, and tridecyl group. group, isotridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, henicosyl group, docosyl group, and the like.
Specifically, the branched alkyl group includes 1-methylethyl group, 1,1-dimethylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3 -methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.

Chain-like alkenyl group which may have a substituent:
The chain alkenyl groups of Rp ⁰² and Rp ⁰³ may be either linear or branched.
Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), a butynyl group, and the like. Examples of the branched alkenyl group include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, and 2-methylpropenyl group.

Examples of the substituent on the chain alkyl group or alkenyl group of Rp ⁰² and Rp ⁰³ include an alkoxy group, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), a halogenated alkyl group, a hydroxyl group, and a carbonyl group. group, nitro group, amino group, the above-mentioned cyclic groups, and the like.

In the above formula (m0-1), Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. That is, Rp ⁰² and Rp ⁰³ may form a cyclic imide together with the imide bond in the formula. The cyclic imide may be monocyclic or polycyclic, and in the case of polycyclic, it may have a crosslinked structure.
The polycyclic cyclic imide structure includes a condensed ring of a cyclic imide and an aromatic hydrocarbon group or a cyclic aliphatic hydrocarbon group.
Specific examples of the cyclic imide include a maleimide ring, a succinimide ring, and a nadimide ring.
Further, the cyclic imide may have a substituent.
Examples of the substituent include hydrocarbon groups. The hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, a cyclic hydrocarbon group, or a chain hydrocarbon group.

In the above formula (m0-1), Rp ⁰² and Rp ⁰³ are preferably bonded to each other to form a ring.

A preferred structure of the cyclic imide in which Rp ⁰² and Rp ⁰³ are bonded to each other to form a ring is shown below. Note that * indicates a bond between the nitrogen atom and the oxygen atom in the above formula (m0-1).

The compound (m0-1) is more preferably a compound represented by the following general formula (m0-11).

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｙｐ^０１は、アルキレン基、アルケニレン基又は２価の環式基である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Yp ⁰¹ is an alkylene group, an alkenylene group, or a divalent cyclic group. ]

In the above formula (m0-11), Rp ⁰¹ and Vp ⁰¹ are the same as explained in the above formula (m0-1).

In the above formula (m0-11), Yp ⁰¹ is an alkylene group, an alkenylene group, or a divalent cyclic group.
Examples of the alkylene group in Yp ⁰¹ include linear alkylene groups having 1 to 8 carbon atoms which may have a substituent. Among them, specifically, an ethylene group [-(CH ₂ ) ₂ -] which may have a substituent, and an n-propylene group [-(CH ₂ ) ₃ -] which may have a substituent are preferable.
Examples of the substituent include hydrocarbon groups. The hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, a cyclic hydrocarbon group, or a chain hydrocarbon group. Among these, specifically, linear hydrocarbon groups such as a methyl group and an ethyl group; and aromatic hydrocarbon groups such as a phenyl group are preferable.

Examples of the alkenylene group in Yp ⁰¹ include linear alkenylene groups having 2 to 6 carbon atoms which may have a substituent. Among these, specifically, ethenylene group is preferable.
Examples of the substituent include the same substituents that the alkylene group may have.

The divalent cyclic group in Yp ⁰¹ may be monocyclic or polycyclic, and in the case of polycyclic, it may have a bridged structure. Here, when the divalent cyclic group in Yp ⁰¹ is monocyclic, it means that it has a monocyclic structure different from the cyclic imide in formula (m0-11). That is, it becomes a polycyclic cyclic imide structure.
The polycyclic cyclic imide structure includes a condensed ring of a cyclic imide and an aromatic hydrocarbon group or a cyclic aliphatic hydrocarbon group.
The cyclic imide is preferably a 5-membered ring or a 6-membered ring.
The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, even more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms.
Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms; Can be mentioned. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.

The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group.
As the aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane.
The aliphatic hydrocarbon group which is a polycyclic group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically Examples include adamantane, norbornane, norbornene, isobornane, tricyclodecane, and tetracyclododecane.

In the above formula (m0-11), Yp ⁰¹ is preferably a divalent cyclic group, more preferably a divalent cyclic aliphatic hydrocarbon group, and is more preferably a divalent cyclic aliphatic hydrocarbon group. More preferred are polycyclic aliphatic hydrocarbon groups. Specifically, norbornane and a group obtained by removing two hydrogen atoms from norbornene are preferred.

Preferred specific examples of the compound represented by the formula (m0-1) are shown below. In each of the following formulas, R ^α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

Among the above examples, the compound (m0-1) is preferably at least one selected from the group consisting of compounds represented by chemical formulas (m01-1-1) to (m01-1-5), respectively; A compound represented by m01-1-1) is more preferred.

≪Compound (m0-2)≫
Compound (m0-2) is a compound represented by the following general formula (m0-2).

［Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。］

[Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

In the above formula (m0-2), Rp ⁰⁴ may be the same as Rp ⁰¹ in the above formula (m0-1).

In the above formula (m0-2), Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group.

The alkyl group in Rp ⁰⁵ is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group, and even more preferably a methyl group.
The alkoxy group in Rp ⁰⁵ is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. is even more preferable.
Examples of the halogen atom in Rp ⁰⁵ include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like, with a fluorine atom being preferred.
The halogenated alkyl group in Rp ⁰⁵ is an alkyl group having 1 to 5 carbon atoms, such as a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group, in which some or all of the hydrogen atoms are the halogen group. Examples include groups substituted with atoms.

In the above formula (m0-2), n ₁ is an integer of 0 to 4, preferably 0 to 2.

In the above formula (m0-2), Rp ⁰⁵ is preferably an alkyl group, an alkoxy group, or a cyano group.

In the above formula (m0-2), Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group.
The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 4 carbon atoms.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH ₂ -], an ethylene group [-(CH ₂ ) ₂ -], a trimethylene group [ -(CH ₂ ) ₃ -], tetramethylene group [-(CH ₂ ) ₄ -], and the like.
The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, and even more preferably 3 or 4 carbon atoms.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ - and other alkylmethylene groups; CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ )CH ₂ -, -C(CH ₂ Alkylethylene groups such as CH ₃ ) ₂ -CH ₂ -; -CH(CH ₃ )CH ₂ CH ₂ -, alkyltrimethylene groups such as -CH ₂ CH(CH ₃ )CH ₂ -; -CH(CH ₃ ) Examples include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ )CH ₂ CH ₂ -, and the like.

In the above formula (m0-2), Rp ⁰⁶ is preferably a linear aliphatic hydrocarbon group among the above, preferably a methylene group, an ethylene group, or a trimethylene group, and more preferably a methylene group.

Preferred specific examples of the compound represented by the formula (m0-2) are shown below.

Among the above examples, compound (m0-2) is selected from the group consisting of compounds represented by chemical formulas (m02-1-1), (m02-1-6) to (m02-1-10), respectively. At least one type is preferred.

≪Alternating copolymer represented by general formula (p0)≫
The following general formula (p0) obtained by copolymerizing the compound represented by the general formula (m0-1) described above and the compound represented by the general formula (m0-2) described above by living radical polymerization. is an alternating copolymer represented by

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０２及びＲｐ^０３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒｐ^０２及びＲｐ^０３は、相互に結合して環を形成していてもよい。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

Rp ⁰¹ , Vp 01 , Rp ⁰² , Rp ⁰³ , Rp ⁰⁴ , ^{Rp 05 ,} Rp ⁰⁶ , n ₁ in the above general formula (p0) are the above general formula (m0-1) or (m0-2). The content is similar to what was explained.

The proportion of the structural units derived from the compound represented by the above general formula (m0-1) is the sum of all structural units (100 mol%) that constitutes the alternating copolymer represented by the above general formula (p0). ), preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even more preferably 40 to 60 mol%.

The proportion of the structural units derived from the compound represented by the above general formula (m0-2) is the sum of all structural units (100 mol% ), preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even more preferably 40 to 60 mol%.

<Process (IIA)>
Step (iia) is a step of hydrolyzing the alternating copolymer represented by the above general formula (p0) to obtain a first polymer compound precursor represented by the following general formula (Pre-1a). be.

Rp ⁰¹ , Vp ⁰¹ , Rp ⁰⁴ , Rp ⁰⁵ , Rp ⁰⁶ , and n ₁ in the above formula (Pre-1a) are the same as those explained in the above formula (m0-1) and the above formula (m0-2). be.

The alternating copolymer can be hydrolyzed by adding the alternating copolymer and an acid component to a solvent and mixing them. Examples of the solvent include those similar to those used in the atom transfer radical polymerization described above.

≪Acid component≫
The acid component is not particularly limited and may be an inorganic acid or an organic acid.
Examples of such acid components include organic acids such as acetic acid, oxalic acid, p-toluenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, and malonic acid; inorganic acids such as sulfuric acid, hydrochloric acid, phosphoric acid, and hydrobromic acid. can be mentioned.
In the manufacturing method of this embodiment, one type of acid component may be used alone, or two or more types may be used in combination.

The temperature conditions during the reaction between the alternating copolymer and the acid component are not particularly limited, and are, for example, about 0 to 120°C.
The reaction time between the alternating copolymer and the acid component is not particularly limited, and is, for example, about 1 to 72 hours.

<Process (iiia)>
In step (iiia), the first polymer compound precursor represented by the above formula (Pre-1a) and the compound represented by the following general formula (Add-1) are reacted to form the following general formula This is a step of obtaining a second polymer compound precursor represented by (Pre-1b-1).

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。Ｒａ^００１、Ｒａ^００２及びＲａ^００３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒａ^００２及びＲａ^００３は、相互に結合して環を形成していてもよい。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. ]

As a method for reacting the first polymer compound precursor with the compound represented by the general formula (Add-1), a method known as esterification can be used. for example,
Using a carbodiimide-based condensing agent (1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC/HCl), etc.) and N,N-dimethyl-4-aminopyridine (DMAP) as a catalyst. One example is a method of esterification.

The temperature conditions for reacting the first polymer compound precursor with the compound represented by the general formula (Add-1) are not particularly limited, and are, for example, about 0 to 120°C.
The reaction time for reacting the first polymer compound precursor with the compound represented by the general formula (Add-1) is not particularly limited, and is, for example, about 1 to 72 hours.

The hydrocarbon group represented by Ra ⁰⁰¹ in the above general formula (Add-1) includes a linear or branched alkyl group, a chain or cyclic alkenyl group, or a cyclic hydrocarbon group.
The linear alkyl group in Ra ¹¹ preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, and the like. Among these, methyl group, ethyl group, and n-butyl group are preferred, and methyl group or ethyl group is more preferred.

The branched alkyl group in Ra ⁰⁰¹ preferably has 3 to 10 carbon atoms, more preferably 3 to 5 carbon atoms. Specific examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, and isopropyl group is preferred.

When Ra ⁰⁰¹ is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group.
As the aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane.
The aliphatic hydrocarbon group which is a polycyclic group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically Examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

When the cyclic hydrocarbon group in Ra ⁰⁰¹ is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, even more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms.
Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; Can be mentioned. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, the aromatic hydrocarbon group in Ra ⁰⁰¹ includes a group obtained by removing one hydrogen atom from the above-mentioned aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); A group in which one hydrogen atom is removed from an aromatic compound (e.g., biphenyl, fluorene, etc.); arylalkyl groups such as phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group). The alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon number.

The cyclic hydrocarbon group in Ra ⁰⁰¹ may have a substituent. Examples of this substituent include -R ^P1 , -R ^P2 -O-R ^P1 , -R ^P2 -CO-R P1 , -R ^P2 -CO-OR ^P1 , -R ^P2 -O-CO-R ^{P1 ,} Examples include -R ^P2 -OH, -R ^P2 -CN, and -R ^P2 -COOH.
Here, R ^P1 is a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent cyclic saturated hydrocarbon group having 6 to 30 carbon atoms. It is an aromatic hydrocarbon group. R ^P2 is a single bond, a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent chain saturated hydrocarbon group having 6 to 30 carbon atoms. It is an aromatic hydrocarbon group. However, some or all of the hydrogen atoms of the chain saturated hydrocarbon group, aliphatic cyclic saturated hydrocarbon group, and aromatic hydrocarbon group of R ^P1 and R ^P2 may be substituted with fluorine atoms. The aliphatic cyclic saturated hydrocarbon group may have one or more of the above substituents, or may have one or more of each of the above substituents.
Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, etc. .
Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, cyclododecyl group, etc. Monocyclic aliphatic saturated hydrocarbon group; bicyclo[2.2.2]octanyl group, tricyclo[5.2.1.02,6]decanyl group, tricyclo[3.3.1.13,7]decanyl group , tetracyclo[6.2.1.13,6.02,7]dodecanyl group, adamantyl group, and other polycyclic aliphatic saturated hydrocarbon groups.
Examples of monovalent aromatic hydrocarbon groups having 6 to 30 carbon atoms include groups obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene.
In R ^P2 , a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms Examples of the group include groups obtained by removing one hydrogen atom from each of the above-mentioned monovalent hydrocarbon groups.

The chain or cyclic alkenyl group in Ra ⁰⁰¹ is preferably an alkenyl group having 2 to 10 carbon atoms.

Examples of the hydrocarbon groups of Ra ⁰⁰² and Ra ⁰⁰³ in the above formula (Add-1) include those similar to those of Ra ⁰⁰¹ above.

When Ra ⁰⁰² and Ra ⁰⁰³ combine with each other to form a ring, a group represented by the following general formula (a1-r2-1), a group represented by the following general formula (a1-r2-2), the following Preferred examples include groups represented by the general formula (a1-r2-3).
On the other hand, when Ra ⁰⁰² and Ra ⁰⁰³ do not bond to each other and are independent hydrocarbon groups, a group represented by the following general formula (a1-r2-4) is preferably mentioned.

［式（ａ１－ｒ２－１）中、Ｒａ’^１０は、炭素数１～１０のアルキル基、又は下記一般式（ａ１－ｒ２－ｒ１）で表される基を示す。Ｒａ’^１１はＲａ’^１０が結合した炭素原子と共に脂肪族環式基を形成する基を示す。式（ａ１－ｒ２－２）中、Ｙａは炭素原子である。Ｘａは、Ｙａと共に環状の炭化水素基を形成する基である。この環状の炭化水素基が有する水素原子の一部又は全部は置換されていてもよい。Ｒａ^０１～Ｒａ^０３は、それぞれ独立して、水素原子、炭素数１～１０の１価の鎖状飽和炭化水素基又は炭素数３～２０の１価の脂肪族環状飽和炭化水素基である。この鎖状飽和炭化水素基及び脂肪族環状飽和炭化水素基が有する水素原子の一部又は全部は置換されていてもよい。Ｒａ^０１～Ｒａ^０３の２つ以上が互いに結合して環状構造を形成していてもよい。式（ａ１－ｒ２－３）中、Ｙａａは炭素原子である。Ｘａａは、Ｙａａと共に脂肪族環式基を形成する基である。Ｒａ^０４は、置換基を有していてもよい芳香族炭化水素基である。式（ａ１－ｒ２－４）中、Ｒａ’^１２及びＲａ’^１３は、それぞれ独立に、炭素数１～１０の１価の鎖状飽和炭化水素基又は水素原子である。この鎖状飽和炭化水素基が有する水素原子の一部又は全部は置換されていてもよい。Ｒａ’^１４は、置換基を有していてもよい炭化水素基である。＊は結合手を示す（以下同じ）。］

[In formula (a1-r2-1), Ra' ¹⁰ represents an alkyl group having 1 to 10 carbon atoms or a group represented by the following general formula (a1-r2-r1). Ra' ¹¹ represents a group forming an aliphatic cyclic group together with the carbon atom to which Ra' ¹⁰ is bonded. In formula (a1-r2-2), Ya is a carbon atom. Xa is a group that forms a cyclic hydrocarbon group together with Ya. Some or all of the hydrogen atoms possessed by this cyclic hydrocarbon group may be substituted. Ra ⁰¹ to Ra ⁰³ are each independently a hydrogen atom, a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms possessed by this chain saturated hydrocarbon group and aliphatic cyclic saturated hydrocarbon group may be substituted. Two or more of Ra ⁰¹ to Ra ⁰³ may be bonded to each other to form a cyclic structure. In formula (a1-r2-3), Yaa is a carbon atom. Xaa is a group that forms an aliphatic cyclic group together with Yaa. Ra ⁰⁴ is an aromatic hydrocarbon group which may have a substituent. In formula (a1-r2-4), Ra' ¹² and Ra' ¹³ are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. Some or all of the hydrogen atoms possessed by this chain saturated hydrocarbon group may be substituted. Ra' ¹⁴ is a hydrocarbon group which may have a substituent. * indicates a bond (the same applies below). ]

［式中、Ｙａ^０は、第４級炭素原子である。Ｒａ^０３１、Ｒａ^０３２及びＲａ^０３３は、それぞれ独立に、置換基を有していてもよい炭化水素基である。但し、Ｒａ^０３１、Ｒａ^０３２及びＲａ^０３３のうちの１つ以上は、少なくとも一つの極性基を有する炭化水素基である。］

[In the formula, Ya ⁰ is a quaternary carbon atom. Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ are each independently a hydrocarbon group which may have a substituent. However, one or more of Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is a hydrocarbon group having at least one polar group. ]

In the above formula (a1-r2-1), the alkyl group having 1 to 10 carbon atoms at Ra' ¹⁰ is preferably a linear or branched alkyl group. Ra' ¹⁰ is preferably an alkyl group having 1 to 5 carbon atoms.

In the formula (a1-r2-r1), Ya ⁰ is a quaternary carbon atom. That is, the number of adjacent carbon atoms bonded to Ya ⁰ (carbon atom) is four.

In the formula (a1-r2-r1), Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ are each independently a hydrocarbon group which may have a substituent. The hydrocarbon groups in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ each independently include a linear or branched alkyl group, a chain or cyclic alkenyl group, or a cyclic hydrocarbon group.

The linear alkyl group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include methyl group, ethyl group, n-propyl group, n-butyl group, and n-pentyl group. Among these, methyl group, ethyl group or n-butyl group are preferred, and methyl group or ethyl group is more preferred.
The branched alkyl group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ preferably has 3 to 10 carbon atoms, more preferably 3 to 5 carbon atoms. Specific examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, and isopropyl group is preferred.
The chain or cyclic alkenyl group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is preferably an alkenyl group having 2 to 10 carbon atoms.

The cyclic hydrocarbon group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group.
As the aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane.
The aliphatic hydrocarbon group which is a polycyclic group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically Examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

The aromatic hydrocarbon group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is a hydrocarbon group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, even more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; Can be mentioned. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring. Specifically, the aromatic hydrocarbon group includes a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); an aromatic group containing two or more aromatic rings; A group obtained by removing one hydrogen atom from a compound (e.g. biphenyl, fluorene, etc.); a group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocycle is substituted with an alkylene group (e.g. benzyl group, phenethyl group) , 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, arylalkyl group such as 2-naphthylethyl group, etc.). The alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon number.

When the hydrocarbon group represented by Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ above is substituted, examples of the substituent include a hydroxy group, a carboxy group, a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.). ), alkoxy groups (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), alkyloxycarbonyl group, etc.

Among the above, the hydrocarbon group which may have a substituent in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is preferably a linear or branched alkyl group which may have a substituent, Straight-chain alkyl groups are more preferred.

However, one or more of Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is a hydrocarbon group having at least a polar group.
"Hydrocarbon group having a polar group" refers to a hydrocarbon group in which the methylene group (-CH ₂ -) is substituted with a polar group, or a hydrocarbon group in which at least one hydrogen atom in the hydrocarbon group is substituted with a polar group. It includes all those substituted with polar groups.
The "hydrocarbon group having a polar group" is preferably a functional group represented by the following general formula (a1-p1).

［式中、Ｒａ^０７は、炭素数２～１２の２価の炭化水素基を表す。Ｒａ^０８は、ヘテロ原子を含む２価の連結基を表す。Ｒａ^０６は、炭素数１～１２の１価の炭化水素基を表す。ｎ_ｐ０は、１～６の整数である。］

[In the formula, Ra ⁰⁷ represents a divalent hydrocarbon group having 2 to 12 carbon atoms. Ra ⁰⁸ represents a divalent linking group containing a heteroatom. Ra ⁰⁶ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms. n _p0 is an integer from 1 to 6. ]

In the formula (a1-p1), Ra ⁰⁷ represents a divalent hydrocarbon group having 2 to 12 carbon atoms.
Ra ⁰⁷ has 2 to 12 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, even more preferably 2 to 4 carbon atoms, and particularly preferably 2 carbon atoms.
The hydrocarbon group in Ra ⁰⁷ is preferably a chain or cyclic aliphatic hydrocarbon group, more preferably a chain hydrocarbon group.
Examples of Ra ⁰⁷ include ethylene group, propane-1,3-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, etc. Linear alkanediyl group; propane-1,2-diyl group, 1-methylbutane-1,3-diyl group, 2-methylpropane-1,3-diyl group, pentane-1,4-diyl group, 2 - Branched alkanediyl groups such as methylbutane-1,4-diyl group; cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1 ,5-diyl group; cycloalkanediyl groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group; Examples include cyclic divalent alicyclic hydrocarbon groups.
Among the above, alkanediyl groups are preferred, and linear alkanediyl groups are more preferred.

In the formula (a1-p1), Ra ⁰⁸ represents a divalent linking group containing a heteroatom.
Ra ⁰⁸ is, for example, -O-, -C(=O)-O-, -C(=O)-, -O-C(=O)-O-, -C(=O)-NH- , -NH-, -NH-C(=NH)- (H may be substituted with a substituent such as an alkyl group or an acyl group), -S-, -S(=O) ₂ -, - Examples include S(=O) ₂ -O-.
Among these, -O-, -C(=O)-O-, -C(=O)-, -O-C(=O)-O- are preferred from the viewpoint of solubility in the developer, and - O-, -C(=O)- are particularly preferred.

In the formula (a1-p1), Ra ⁰⁶ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms.
The number of carbon atoms in Ra ⁰⁶ is 1 to 12, from the viewpoint of solubility in a developer, preferably 1 to 8 carbon atoms, more preferably 1 to 5 carbon atoms, even more preferably 1 to 3 carbon atoms, and 1 or 2 is particularly preferred, and 1 is most preferred.

Examples of the hydrocarbon group in Ra ⁰⁶ include a chain hydrocarbon group, a cyclic hydrocarbon group, or a combination of a chain and a cyclic hydrocarbon group.
Examples of chain hydrocarbon groups include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n- -heptyl group, 2-ethylhexyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group and the like.

The cyclic hydrocarbon group may be an alicyclic hydrocarbon group or an aromatic hydrocarbon group.
The alicyclic hydrocarbon group may be monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, and methyl. Examples include cycloalkyl groups such as cyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, cycloheptyl group, and cyclodecyl group. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1-(adamantan-1-yl)alkan-1-yl group, norbornyl group, group, methylnorbornyl group, isobornyl group, etc.
Examples of aromatic hydrocarbon groups include phenyl group, naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group. , biphenyl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group and the like.

From the viewpoint of solubility in a developer, Ra ⁰⁶ is preferably a chain hydrocarbon group, more preferably an alkyl group, and even more preferably a linear alkyl group.

In the formula (a1-p1), n _p0 is an integer of 1 to 6, preferably an integer of 1 to 3, more preferably 1 or 2, and even more preferably 1.

Specific examples of the hydrocarbon group having at least a polar group are shown below.
In the following formula, * is a bond bonded to the quaternary carbon atom (Ya ⁰ ).

In the above formula (a1-r2-r1), among Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ , the number of hydrocarbon groups having at least a polar group is one or more, but the number of hydrocarbon groups is one or more. For example, it is preferably one or two of Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ , and particularly preferably one.

The hydrocarbon group having at least a polar group may have a substituent other than the polar group. Examples of this substituent include a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.) and a halogenated alkyl group having 1 to 5 carbon atoms.

In formula (a1-r2-1), Ra' ¹¹ (the aliphatic cyclic group formed together with the carbon atom to which Ra' ¹⁰ is bonded) is the monocyclic group of Ra ⁰⁰¹ in the above general formula (Add-1) or The groups listed as polycyclic aliphatic hydrocarbon groups are preferred.

In formula (a1-r2-2), the cyclic hydrocarbon group formed by Xa together with Ya is the cyclic monovalent hydrocarbon group ( ^aliphatic hydrocarbon Examples include groups in which one or more hydrogen atoms are further removed from the group).
The cyclic hydrocarbon group formed by Xa and Ya may have a substituent. Examples of this substituent include the same substituents as the substituent that the cyclic hydrocarbon group in Ra ⁰⁰¹ in the above general formula (Add-1) may have.
In formula (a1-r2-2), examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra ⁰¹ to Ra ⁰³ include methyl group, ethyl group, propyl group, butyl group, pentyl group, etc. group, hexyl group, heptyl group, octyl group, decyl group, etc.
Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms in Ra ⁰¹ to Ra ⁰³ include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a cyclodecyl group. monocyclic aliphatic saturated hydrocarbon groups such as cyclododecyl group; bicyclo[2.2.2]octanyl group, tricyclo[5.2.1.02,6]decanyl group, tricyclo[3.3.1 Examples thereof include polycyclic aliphatic saturated hydrocarbon groups such as a tetracyclo[6.2.1.13,6.02,7]decanyl group, a tetracyclo[6.2.1.13,6.02,7]dodecanyl group, and an adamantyl group.

Examples of the substituent of the chain saturated hydrocarbon group or aliphatic cyclic saturated hydrocarbon group represented by Ra ⁰¹ to Ra ⁰³ above include the same groups as Ra ⁰⁵ above.

Groups containing a carbon-carbon double bond formed by two or more of Ra ⁰¹ to Ra ⁰³ bonding to each other to form a cyclic structure include, for example, a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, a methyl Examples include a cyclohexenyl group, a cyclopentylideneethenyl group, a cyclohexylideneethenyl group, and the like.

In the formula (a1-r2-3), the aliphatic cyclic group formed by Xaa together with Yaa is a carbonized aliphatic group that is a monocyclic group or a polycyclic group in Ra ⁰⁰¹ in the above general formula (Add-1). The groups listed as hydrogen groups are preferred.
In formula (a1-r2-3), the aromatic hydrocarbon group for Ra ⁰⁴ includes a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among these, Ra ⁰⁴ is preferably a group in which one or more hydrogen atoms are removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, and more preferably a group in which one or more hydrogen atoms are removed from benzene, naphthalene, anthracene, or phenanthrene. , a group obtained by removing one or more hydrogen atoms from benzene, naphthalene or anthracene is more preferable, a group obtained by removing one or more hydrogen atoms from benzene or naphthalene is particularly preferable, and a group obtained by removing one or more hydrogen atoms from benzene is most preferable. preferable.

Examples of substituents that Ra ⁰⁴ in formula (a1-r2-3) may have include methyl group, ethyl group, propyl group, hydroxyl group, carboxyl group, halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), alkoxy groups (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), alkyloxycarbonyl group, etc.

In formula (a1-r2-4), Ra' ¹² and Ra' ¹³ are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. The monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra' ¹² and Ra' ¹³ is the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra ⁰¹ to Ra ⁰³ above. Examples include those similar to the group. Some or all of the hydrogen atoms possessed by this chain saturated hydrocarbon group may be substituted.
Ra' ¹² and Ra' ¹³ are preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, even more preferably a methyl group or an ethyl group, and particularly a methyl group. preferable.
When the chain saturated hydrocarbon group represented by Ra' ¹² and Ra' ¹³ above is substituted, examples of the substituent include the same groups as Ra ⁰⁵ above.

In formula (a1-r2-4), Ra' ¹⁴ is a hydrocarbon group which may have a substituent. The hydrocarbon group for Ra' ¹⁴ includes a linear or branched alkyl group, or a cyclic hydrocarbon group.

The linear alkyl group in Ra' ¹⁴ preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, and the like. Among these, methyl group, ethyl group or n-butyl group are preferred, and methyl group or ethyl group is more preferred.

The branched alkyl group in Ra' ¹⁴ preferably has 3 to 10 carbon atoms, more preferably 3 to 5 carbon atoms. Specific examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, and isopropyl group is preferred.

When Ra' ¹⁴ is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group.
As the aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane.
The aliphatic hydrocarbon group which is a polycyclic group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically Examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

Examples of the aromatic hydrocarbon group in Ra' ¹⁴ include the same aromatic hydrocarbon groups as in Ra ⁰⁴ . Among these, Ra' ¹⁴ is preferably a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, and more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, or phenanthrene. Preferably, a group obtained by removing one or more hydrogen atoms from benzene, naphthalene or anthracene is more preferable, a group obtained by removing one or more hydrogen atoms from naphthalene or anthracene is particularly preferable, and a group obtained by removing one or more hydrogen atoms from naphthalene is more preferable. Most preferred.
Examples of the substituents that Ra' ¹⁴ may have include the same substituents as the substituents that Ra ⁰⁴ may have.

When Ra' ¹⁴ in formula (a1-r2-4) is a naphthyl group, the position bonded to the tertiary carbon atom in formula (a1-r2-4) is the 1st or 2nd position of the naphthyl group. It may be either.
When Ra' ¹⁴ in formula (a1-r2-4) is an anthryl group, the position bonded to the tertiary carbon atom in formula (a1-r2-4) is the 1st, 2nd or 2nd position of the anthryl group. It can be any of the 9th place.

Specific examples of the group represented by the formula (a1-r2-1) are listed below.

Specific examples of the group represented by the above formula (a1-r2-2) are listed below.

Specific examples of the group represented by the above formula (a1-r2-3) are listed below.

Specific examples of the group represented by the above formula (a1-r2-4) are listed below.

Rp ⁰¹ , Vp ⁰¹ , Rp ⁰⁴ , Rp ⁰⁵ , Rp ⁰⁶ , and n ₁ in the above formula (Pre-1b-1) are the same as those explained in the above formula (m0-1) and the above formula (m0-2). The same is true.

Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ in the above formula (Pre-1b-1) are each independently a hydrocarbon group which may have a substituent.
In the above formula (Pre-1b-1), -C(Ra ⁰⁰¹ ) (Ra ⁰⁰² ) (Ra ⁰⁰³ ) is an acid dissociable group (tertiary alkyl ester type acid dissociable group). "Acid-dissociable group" means (i) a group having acid-dissociable properties that allows the bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group to be cleaved by the action of an acid; (ii) A group in which the bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group can be cleaved by further decarboxylation reaction after some bonds are cleaved by the action of an acid. , refers to both.
Specifically, the tertiary carbon atom of -C(Ra ⁰⁰¹ )(Ra ⁰⁰² )(Ra ⁰⁰³ ) in the above formula (Pre-1b-1) and the oxygen atom adjacent to the tertiary carbon atom The bond between , is cleaved and -C(Ra ⁰⁰¹ )(Ra ⁰⁰² )(Ra ⁰⁰³ ) is dissociated, a highly polar group (carboxy group) is generated, and the polarity increases.

Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ in the above formula (Pre-1b-1) are the same as those explained as the hydrocarbon group in the above formula (Add-1).

<Process (iva)>
Step (iva) is a step of hydrolyzing the second polymer compound precursor to obtain the polymer compound (A01) represented by the general formula (p1) (hereinafter also referred to as step (iva)). It is.

The second polymer compound precursor can be hydrolyzed by adding and mixing the second polymer compound precursor and a base component to a solvent. Examples of the solvent include those similar to those used in the atom transfer radical polymerization described above.

≪Base component≫
The base component is not particularly limited, and examples thereof include sodium hydroxide, potassium hydroxide, potassium carbonate, and the like.
In the manufacturing method of this embodiment, one type of base component may be used alone, or two or more types may be used in combination.

The temperature conditions during the reaction between the second polymer compound precursor and the base component are not particularly limited, and are, for example, about 0 to 60°C.
The reaction time between the second polymer compound precursor and the base component is not particularly limited, and is, for example, about 1 to 24 hours.

Rp ⁰¹ , Vp ⁰¹ , Rp ⁰⁴ , Rp ⁰⁵ , and n ₁ in the above general formula (p1) are the same as explained in the above formula (m0-1) and the above formula (m0-2).
Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ in the above general formula (p1) are the same as explained as the hydrocarbon group in the above formula (Add-1).

<Process (va)>
This is a step of preparing a resist composition by mixing a polymer compound (A01) and an organic solvent.

[Resist composition]
The resist composition in this embodiment is one that generates acid upon exposure to light and changes its solubility in a developer due to the action of the acid, and is a base material component whose solubility in the developer changes due to the action of the acid. Contains (A) (hereinafter also referred to as "component (A)"). The above-mentioned polymer compound (A01) is included in the component (A), and the component (A) is a polymer compound (A1) other than the polymer compound (A01) (hereinafter referred to as (A1)). ) component) may also be included.

When a resist film is formed using the resist composition in this embodiment and the resist film is selectively exposed to light, acid is generated in the exposed areas of the resist film, and due to the action of the acid, the (A) component While the solubility of component (A) in the developing solution changes, the solubility of component (A) in the developing solution does not change in the unexposed areas of the resist film. Differences in solubility in liquids occur. Therefore, when the resist film is developed, if the resist composition is positive type, the exposed portion of the resist film is dissolved and removed to form a positive resist pattern, and if the resist composition is negative type, the resist film is not formed. The exposed portion is dissolved and removed to form a negative resist pattern.

In this specification, a resist composition in which the exposed portion of the resist film is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and a resist composition in which the unexposed portion of the resist film is dissolved and removed to form a negative resist pattern is referred to as a positive resist composition. The resist composition formed is called a negative resist composition.
The resist composition in this embodiment may be a positive resist composition or a negative resist composition.
Further, the resist composition in this embodiment may be used in an alkaline development process using an alkaline developer in the development process during resist pattern formation, and a developer containing an organic solvent (organic developer) in the development process. It may be used for a solvent development process using.
In other words, the resist composition in this embodiment is a "positive resist composition for alkaline development process" that forms a positive resist pattern in an alkaline development process, and a "solvent developable resist composition that forms a negative resist pattern in a solvent development process." Negative resist composition for process use.

The resist composition in this embodiment has an acid-generating ability that generates an acid upon exposure to light, and the component (A) may generate an acid upon exposure, and the resist composition may include an additive blended separately from the component (A). The agent component may generate acid upon exposure to light.
Specifically, the resist composition may contain (1) an acid generator component (B) that generates an acid upon exposure (hereinafter referred to as "component (B)"); (2) Component (A) may be a component that generates an acid upon exposure to light; (3) Component (A) may be a component that generates an acid upon exposure to light, and further contains the component (B); Good too.
That is, in the case of (2) or (3) above, the component (A) is "a base material component that generates acid upon exposure and whose solubility in a developer changes due to the action of the acid."
In the case of (2) or (3) above, it means that the (A) component contains the above (A1) component, and the (A1) component contains a component that generates an acid upon exposure.
The resist composition in this embodiment is preferably the case (1) above.

Examples of the resist composition in this embodiment include a resist composition containing component (A), component (B), and component (S).

<(A) component>
Component (A) in the resist composition is a base material component whose solubility in a developer changes due to the action of an acid, and includes the above-mentioned component (A0). By using the (A0) component, the polarity of the base material component changes before and after exposure, so that good development contrast can be obtained not only in an alkaline development process but also in a solvent development process.
Further, since the component (A0) is manufactured by the process described above, variations in each constituent unit are suppressed, and a resist pattern with good lithography characteristics can be formed.

When applying an alkaline development process, the base material component containing the component (A0) is poorly soluble in an alkaline developer before exposure, and for example, when an acid is generated from the component (B) by exposure, the acid Due to the action of , the polarity increases and the solubility in an alkaline developer increases. Therefore, when forming a resist pattern, when a resist film obtained by coating the resist composition on a support is selectively exposed to light, the exposed areas of the resist film change from being poorly soluble to soluble in an alkaline developer. On the other hand, since the unexposed portions of the resist film remain poorly soluble in alkali and do not change, a positive resist pattern is formed by alkali development.

On the other hand, when applying a solvent development process, the base material component containing the (A0) component has high solubility in an organic developer before exposure, and for example, if an acid is generated from the (B) component upon exposure, The action of the acid increases the polarity and reduces the solubility in organic developers. Therefore, when forming a resist pattern, when a resist film obtained by coating the resist composition on a support is selectively exposed to light, the exposed areas of the resist film change from being soluble to slightly soluble in an organic developer. While the resist film changes, the unexposed areas of the resist film remain soluble and do not change, so by developing with an organic developer, contrast can be created between the exposed areas and the unexposed areas, and a negative resist pattern is created. It is formed.

In the resist composition according to the present embodiment, one kind of component (A) may be used alone, or two or more kinds may be used in combination.

・About component (A1) Component (A1) is a polymer compound that does not fall under component (A0), such as a structural unit (a1) containing an acid-decomposable group whose polarity increases by the action of an acid, a lactone-containing ring, etc. A structural unit (a2) containing a formula group, a -SO ₂ --containing cyclic group, or a carbonate-containing cyclic group, a structural unit (a3) containing a polar group-containing aliphatic hydrocarbon group (however, the structural unit (a1) or the structural unit (excluding those corresponding to unit (a2)), a structural unit (a10) containing a hydroxystyrene skeleton, and a structural unit (a4) containing an acid-nondissociable aliphatic cyclic group. Examples include compounds.

≪Constituent unit (a1)≫
The structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity increases under the action of an acid.
An "acid-decomposable group" is a group having acid-decomposability that allows at least a portion of the bonds in the structure of the acid-decomposable group to be cleaved by the action of an acid.
Examples of acid-decomposable groups whose polarity increases under the action of acids include groups that decompose under the action of acids to produce polar groups.
Examples of the polar group include a carboxy group, a hydroxyl group, an amino group, and a sulfo group (-SO ₃ H). Among these, a polar group containing -OH in its structure (hereinafter sometimes referred to as "OH-containing polar group") is preferred, a carboxy group or a hydroxyl group is more preferred, and a carboxy group is particularly preferred.
More specifically, the acid-decomposable group includes a group in which the polar group is protected with an acid-dissociable group (for example, a group in which the hydrogen atom of an OH-containing polar group is protected with an acid-dissociable group).

Here, the term "acid-dissociable group" refers to (i) a group having acid-dissociable properties in which the bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group can be cleaved by the action of an acid; or (ii) after some bonds are cleaved by the action of an acid, a decarboxylation reaction occurs, whereby the bond between the acid-dissociable group and the atom adjacent to the acid-dissociable group is cleaved; This refers to both of the groups that can be obtained.
The acid-dissociable group constituting the acid-dissociable group needs to be a group with lower polarity than the polar group generated by dissociation of the acid-dissociable group. When is dissociated, a polar group having higher polarity than the acid-dissociable group is generated and the polarity increases. As a result, the polarity of the entire component (A1) increases. As the polarity increases, the relative solubility in the developer changes; when the developer is an alkaline developer, the solubility increases, and when the developer is an organic developer, the solubility decreases. Decrease.

Examples of the acid-dissociable group include those that have been proposed as acid-dissociable groups for base resins for chemically amplified resist compositions.
Specifically, examples of acid-dissociable groups proposed as acid-dissociable groups for base resins for chemically amplified resist compositions include "acetal-type acid-dissociable groups,""tertiary alkyl ester-type acid-dissociable groups," and " ``tertiary alkyloxycarbonylic acid dissociable group''.
The acetal-type acid-dissociable group is an acetal-type acid-dissociable group represented by -C(Ra ⁰⁰⁴ )(Ra ⁰⁰⁵ )-O-(Ra ⁰⁰⁶ ) in the formula (Pre-1b-2) described below. The same is true.
The tertiary alkyl ester type acid dissociable group is a tertiary alkyl ester type acid dissociable group represented by -C(Ra ⁰⁰¹ )(Ra ⁰⁰² )(Ra ⁰⁰³ ) in the above formula (Pre-1b-1). This is the same as explained in the previous section.

Tertiary alkyloxycarbonylic acid dissociable group:
Among the polar groups, the acid-dissociable group that protects the hydroxyl group is, for example, an acid-dissociable group represented by the following general formula (a1-r-3) (hereinafter referred to as a "tertiary alkyloxycarbonyl acid-dissociable group" for convenience). ”) can be mentioned.

［式中、Ｒａ’^７～Ｒａ’^９はそれぞれアルキル基である。］

[In the formula, Ra' ⁷ to Ra' ⁹ are each an alkyl group. ]

In formula (a1-r-3), Ra' ⁷ to Ra' ⁹ are each preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms.
Further, the total number of carbon atoms in each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

The structural unit (a1) is a structural unit derived from an acrylic ester in which the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, a structural unit derived from acrylamide, hydroxystyrene or hydroxyl. A structural unit in which at least a portion of the hydrogen atoms in the hydroxyl group of a structural unit derived from a styrene derivative is protected by a substituent containing the acid-decomposable group, a structural unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative, - Examples include structural units in which at least a portion of the hydrogen atoms in C(=O)-OH are protected by a substituent containing the acid-decomposable group.

The structural unit (a1) is preferably a structural unit derived from an acrylic ester in which the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent.
Preferred specific examples of the structural unit (a1) include structural units represented by the following general formula (a1-1) or (a1-2).

［式中、Ｒは、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖａ^１は、エーテル結合を有していてもよい２価の炭化水素基である。ｎ_ａ１は、０～２の整数である。Ｒａ^１は、上記の一般式（ａ１－ｒ－１）、（ａ１－ｒ２－１）、（ａ１－ｒ２－２）、（ａ１－ｒ２－３）、又は（ａ１－ｒ２－４）で表される酸解離性基である。Ｗａ^１はｎ_ａ２＋１価の炭化水素基であり、ｎ_ａ２は１～３の整数であり、Ｒａ^２は上記の一般式（ａ１－ｒ－１）又は（ａ１－ｒ－３）で表される酸解離性基である。］

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Va ¹ is a divalent hydrocarbon group which may have an ether bond. n _a1 is an integer from 0 to 2. Ra ¹ is represented by the above general formula (a1-r-1), (a1-r2-1), (a1-r2-2), (a1-r2-3), or (a1-r2-4). It is an acid-dissociable group. Wa ¹ is n _a2 + monovalent hydrocarbon group, n _a2 is an integer of 1 to 3, and Ra ² is represented by the above general formula (a1-r-1) or (a1-r-3). It is an acid dissociable group. ]

In the formula (a1-1), the alkyl group having 1 to 5 carbon atoms in R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group, an ethyl group. , propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like, with a fluorine atom being particularly preferred.
R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and most preferably a hydrogen atom or a methyl group from the viewpoint of industrial availability.

In the formula (a1-1), the divalent hydrocarbon group in Va ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

The aliphatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ may be saturated or unsaturated, and is usually preferably saturated.
More specifically, the aliphatic hydrocarbon group includes a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in its structure, and the like.

The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. .
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH ₂ -], an ethylene group [-(CH ₂ ) ₂ -], a trimethylene group [ -(CH ₂ ) ₃ -], tetramethylene group [-(CH ₂ ) ₄ -], pentamethylene group [-(CH ₂ ) ₅ -], and the like.
The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, further preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ - and other alkylmethylene groups; CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ )CH ₂ -, -C(CH ₂ Alkylethylene groups such as CH ₃ ) ₂ -CH ₂ -; -CH(CH ₃ )CH ₂ CH ₂ -, alkyltrimethylene groups such as -CH ₂ CH(CH ₃ )CH ₂ -; -CH(CH ₃ ) Examples include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ )CH ₂ CH ₂ -, and the like. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

Examples of the aliphatic hydrocarbon group containing a ring in the structure include an alicyclic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), and an alicyclic hydrocarbon group in which the alicyclic hydrocarbon group is linear or branched. Examples thereof include a group bonded to the end of a chain aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those similar to the linear aliphatic hydrocarbon group or the branched aliphatic hydrocarbon group.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane. , norbornane, isobornane, tricyclodecane, tetracyclododecane, and the like.

The aromatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ is a hydrocarbon group having an aromatic ring.
Such an aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, even more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 12 carbon atoms. . However, the number of carbon atoms does not include the number of carbon atoms in substituents.
Specifically, examples of the aromatic ring possessed by the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; Examples include aromatic heterocycles substituted with atoms. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, the aromatic hydrocarbon group includes a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group); a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group); ) in which one of the hydrogen atoms is substituted with an alkylene group (for example, arylalkyl such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group) (a group obtained by removing one hydrogen atom from an aryl group in the group), and the like. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon number.

In the above formula (a1-1), Ra ¹ is the above formula (a1-r-1), (a1-r2-1), (a1-r2-2), (a1-r2-3), or (a1 -r2-4) is an acid dissociable group.

In the formula (a1-2), the n _a2 +1-valent hydrocarbon group in Wa ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group without aromaticity, and may be saturated or unsaturated, and is usually preferably saturated. The aliphatic hydrocarbon group is a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in its structure, or a linear or branched aliphatic hydrocarbon group. Examples include groups in which a ring-containing aliphatic hydrocarbon group is combined in the structure.
The n _a2 +1 valence is preferably 2 to 4, more preferably 2 or 3.

In the above formula (a1-2), Ra ² is an acid dissociable group represented by the above general formula (a1-r-1) or (a1-r-3).

Specific examples of the structural unit represented by the above formula (a1-1) are shown below. In each of the following formulas, R ^α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

Specific examples of the structural unit represented by the above formula (a1-2) are shown below.

The number of structural units (a1) contained in the component (A1) may be one or more.
The proportion of the structural unit (a1) in the component (A1) is preferably 5 to 80 mol%, and 10 to 75 mol%, based on the total (100 mol%) of all the structural units constituting the component (A1). More preferably, 20 to 60 mol% is even more preferable.
By setting the proportion of the structural unit (a1) to the lower limit of the above-mentioned preferred range or more, lithography properties such as sensitivity, resolution, and roughness improvement are improved. On the other hand, if it is below the upper limit of the above-mentioned preferable range, a balance with other structural units can be maintained, and various lithography properties will be improved.

≪Constituent unit (a2)≫
The structural unit (a2) is a structural unit containing a lactone-containing cyclic group, a -SO ₂ --containing cyclic group, or a carbonate-containing cyclic group (excluding those corresponding to the structural unit (a1)).
The lactone-containing cyclic group, -SO ₂ --containing cyclic group, or carbonate-containing cyclic group of the structural unit (a2) is important for the adhesion of the resist film to the substrate when the component (A1) is used to form the resist film. It is effective in increasing sexuality. In addition, by having the structural unit (a2), for example, the acid diffusion length can be appropriately adjusted, the adhesion of the resist film to the substrate can be increased, and the solubility during development can be appropriately adjusted, so that the lithography properties can be improved. etc. will be good.

The term "lactone-containing cyclic group" refers to a cyclic group containing a ring containing -OC(=O)- (lactone ring) in its ring skeleton. The lactone ring is counted as the first ring, and when there is only a lactone ring, it is called a monocyclic group, and when it has other ring structures, it is called a polycyclic group regardless of the structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.
The lactone-containing cyclic group in the structural unit (a2) is not particularly limited and any arbitrary group can be used. Specifically, groups represented by the following general formulas (a2-r-1) to (a2-r-7) can be mentioned.

［式中、Ｒａ’^２１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、－ＣＯＯＲ”、－ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子、アルキル基、ラクトン含有環式基、カーボネート含有環式基、又は－ＳＯ_２－含有環式基であり；Ａ”は酸素原子（－Ｏ－）もしくは硫黄原子（－Ｓ－）を含んでいてもよい炭素数１～５のアルキレン基、酸素原子または硫黄原子であり、ｎ’は０～２の整数であり、ｍ’は０または１である。］

[In the formula, Ra' ²¹ is each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group. Yes; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ --containing cyclic group; A" is an oxygen atom (-O-) or a sulfur atom (- S-) is an alkylene group having 1 to 5 carbon atoms, an oxygen atom, or a sulfur atom, n' is an integer of 0 to 2, and m' is 0 or 1. ]

In the general formulas (a2-r-1) to (a2-r-7), the alkyl group at Ra' ²¹ is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specific examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, hexyl group, and the like. Among these, a methyl group or an ethyl group is preferred, and a methyl group is particularly preferred.
The alkoxy group for Ra' ²¹ is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, a group in which the alkyl group mentioned above as the alkyl group in Ra' ²¹ and an oxygen atom (-O-) are connected can be mentioned.
Examples of the halogen atom in Ra' ²¹ include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like, with a fluorine atom being preferred.
Examples of the halogenated alkyl group at Ra' ²¹ include groups in which part or all of the hydrogen atoms of the alkyl group at Ra' ²¹ are substituted with the halogen atoms. As the halogenated alkyl group, a fluorinated alkyl group is preferable, and a perfluoroalkyl group is particularly preferable.

In -COOR'' and -OC(=O)R'' in Ra' ²¹ , R'' is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or an -SO ₂ -containing cyclic group. It is.
The alkyl group in R'' may be linear, branched, or cyclic, and preferably has 1 to 15 carbon atoms.
When R'' is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably a methyl group or an ethyl group. preferable.
When R'' is a cyclic alkyl group, it preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms.Specifically, fluorine atom or a group obtained by removing one or more hydrogen atoms from a monocycloalkane which may or may not be substituted with a fluorinated alkyl group; polycycloalkanes such as bicycloalkanes, tricycloalkanes, and tetracycloalkanes Examples include groups in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tri- Examples include groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as cyclodecane and tetracyclododecane.
Examples of the lactone-containing cyclic group in R'' include the same groups as those represented by the general formulas (a2-r-1) to (a2-r-7).
The carbonate-containing cyclic group in R'' is the same as the carbonate-containing cyclic group described below, and specifically, groups represented by general formulas (ax3-r-1) to (ax3-r-3), respectively. can be mentioned.
The -SO ₂ --containing cyclic group in R'' is the same as the -SO ₂ --containing cyclic group described below, and specifically, general formulas (a5-r-1) to (a5-r-4) Examples include groups represented by the following.
The hydroxyalkyl group in Ra' ²¹ preferably has 1 to 6 carbon atoms, and specifically includes a group in which at least one hydrogen atom of the alkyl group in Ra' ²¹ is substituted with a hydroxyl group. .

In the general formulas (a2-r-2), (a2-r-3), and (a2-r-5), the alkylene group having 1 to 5 carbon atoms in A'' is a linear or branched alkylene group. Alkylene groups are preferred, and include methylene groups, ethylene groups, n-propylene groups, isopropylene groups, etc. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples include the terminal or carbon atoms of the alkylene group. Examples include groups in which -O- or -S- exists between atoms, such as -O-CH ₂ -, -CH ₂ -O-CH ₂ -, -S-CH ₂ -, -CH ₂ -S-CH _2- , etc.A'' is preferably an alkylene group having 1 to 5 carbon atoms or -O-, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.

Specific examples of groups represented by general formulas (a2-r-1) to (a2-r-7) are listed below.

"-SO ₂ --containing cyclic group" refers to a cyclic group containing a ring containing -SO ₂ - in its ring skeleton, and specifically, the sulfur atom (S) in -SO ₂ - A cyclic group that forms part of the ring skeleton of a cyclic group. A ring containing -SO ₂ - in its ring skeleton is counted as the first ring, and if this ring only exists, it is a monocyclic group, and if it has other ring structures, it is a polycyclic group regardless of the structure. It is called. The -SO ₂ --containing cyclic group may be a monocyclic group or a polycyclic group.
-SO ₂ --containing cyclic group is particularly a cyclic group containing -O-SO ₂ - in its ring skeleton, that is, -O-S- in -O-SO ₂ - forms part of the ring skeleton. Preferably, it is a cyclic group containing a sultone ring.
More specific examples of the -SO ₂ --containing cyclic group include groups represented by the following general formulas (a5-r-1) to (a5-r-4), respectively.

［式中、Ｒａ’^５１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、－ＣＯＯＲ”、－ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子、アルキル基、ラクトン含有環式基、カーボネート含有環式基、又は－ＳＯ_２－含有環式基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１～５のアルキレン基、酸素原子または硫黄原子であり、ｎ’は０～２の整数である。］

[In the formula, Ra' ⁵¹ is each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group. Yes; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ --containing cyclic group; A" is a carbon that may contain an oxygen atom or a sulfur atom It is an alkylene group of number 1 to 5, an oxygen atom or a sulfur atom, and n' is an integer of 0 to 2. ]

In the general formulas (a5-r-1) to (a5-r-2), A'' is the general formula (a2-r-2), (a2-r-3), (a2-r-5) It is the same as "A" in the middle.
The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group in Ra' ⁵¹ are represented by the above general formulas (a2-r-1) to ( The same compounds as those mentioned in the explanation of Ra' ²¹ in a2-r-7) can be mentioned.
Specific examples of groups represented by general formulas (a5-r-1) to (a5-r-4) are listed below. "Ac" in the formula represents an acetyl group.

The term "carbonate-containing cyclic group" refers to a cyclic group containing a ring containing -OC(=O)-O- (carbonate ring) in its ring skeleton. The carbonate ring is counted as the first ring, and when it has only a carbonate ring, it is called a monocyclic group, and when it has other ring structures, it is called a polycyclic group regardless of the structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group.
Any carbonate ring-containing cyclic group can be used without particular limitation. Specifically, groups represented by the following general formulas (ax3-r-1) to (ax3-r-3) can be mentioned.

［式中、Ｒａ’^ｘ３１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、－ＣＯＯＲ”、－ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子、アルキル基、ラクトン含有環式基、カーボネート含有環式基、又は－ＳＯ_２－含有環式基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１～５のアルキレン基、酸素原子または硫黄原子であり、ｐ’は０～３の整数であり、ｑ’は０または１である。］

[In the ^formula , Ra'Yes;R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ --containing cyclic group; A" is a carbon that may contain an oxygen atom or a sulfur atom It is an alkylene group of number 1 to 5, an oxygen atom or a sulfur atom, p' is an integer of 0 to 3, and q' is 0 or 1. ]

In the general formulas (ax3-r-2) to (ax3-r-3), A'' is the general formula (a2-r-2), (a2-r-3), (a2-r-5) It is the same as "A" in the middle.
The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group in Ra' ³¹ are represented by the above general formulas (a2-r-1) to ( The same compounds as those mentioned in the explanation of Ra' ²¹ in a2-r-7) can be mentioned.
Specific examples of the groups represented by the general formulas (ax3-r-1) to (ax3-r-3) are listed below.

Among these, the structural unit (a2) is preferably a structural unit derived from an acrylic ester in which the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent.
The structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

［式中、Ｒは水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｙａ^２１は単結合または２価の連結基である。Ｌａ^２１は－Ｏ－、－ＣＯＯ－、－ＣＯＮ（Ｒ’）－、－ＯＣＯ－、－ＣＯＮＨＣＯ－又は－ＣＯＮＨＣＳ－であり、Ｒ’は水素原子またはメチル基を示す。ただしＬａ^２１が－Ｏ－の場合、Ｙａ^２１は－ＣＯ－にはならない。Ｒａ^２１はラクトン含有環式基、カーボネート含有環式基、又は－ＳＯ_２－含有環式基である。］

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ya ²¹ is a single bond or a divalent linking group. La ²¹ is -O-, -COO-, -CON(R')-, -OCO-, -CONHCO- or -CONHCS-, and R' represents a hydrogen atom or a methyl group. However, when La ²¹ is -O-, Ya ²¹ does not become -CO-. Ra ²¹ is a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ -containing cyclic group. ]

In the formula (a2-1), R is the same as above. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is particularly preferred.

In the above formula (a2-1), the divalent linking group of Ya ²¹ is not particularly limited, but includes a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, etc. etc. are preferably mentioned. The explanation about the divalent hydrocarbon group ^{which may have a substituent and the divalent linking group containing a hetero atom in Ya 21 is} as follows: The explanations are the same as those for the divalent hydrocarbon group which may have a group and the divalent linking group containing a hetero atom.
Ya ²¹ is preferably a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof. .

In the formula (a2-1), Ra ²¹ is a lactone-containing cyclic group, a -SO ₂ --containing cyclic group, or a carbonate-containing cyclic group.
The lactone-containing cyclic group, -SO ₂ --containing cyclic group, and carbonate-containing cyclic group in Ra ²¹ are each represented by the aforementioned general formulas (a2-r-1) to (a2-r-7), respectively. groups represented by general formulas (a5-r-1) to (a5-r-4), groups represented by general formulas (ax3-r-1) to (ax3-r-3), respectively. are preferably mentioned.
Among these, lactone-containing cyclic groups or -SO ₂ --containing cyclic groups are preferred, and those of the general formula (a2-r-1), (a2-r-2), (a2-r-6) or (a5-r The groups represented by -1) are more preferred. Specifically, the chemical formulas (r-lc-1-1) to (r-lc-1-7), (r-lc-2-1) to (r-lc-2-18), (r- More preferred are any of the groups represented by lc-6-1), (r-sl-1-1), and (r-sl-1-18), respectively.

The number of structural units (a2) contained in the component (A1) may be one or more.
When the component (A1) has a structural unit (a2), the proportion of the structural unit (a2) is 20 to 70 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). It is preferably 40 to 60 mol%, more preferably 40 to 60 mol%.
By setting the ratio of the structural unit (a2) to a preferable lower limit or more, the effect of containing the structural unit (a2) can be sufficiently obtained, and by setting the ratio to the upper limit or less, a balance with other structural units can be achieved. Various lithography properties can be improved.

≪Constituent unit (a3)≫
The structural unit (a3) is a structural unit containing a polar group-containing aliphatic hydrocarbon group (excluding those corresponding to the structural unit (a1) and the structural unit (a2)). When the component (A1) has the structural unit (a3), it can, for example, appropriately adjust the acid diffusion length, increase the adhesion of the resist film to the substrate, appropriately adjust the solubility during development, and improve etching resistance. Due to the effect of improving the lithography characteristics, etc., the lithography characteristics become better.

Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and a hydroxyalkyl group in which some of the hydrogen atoms of an alkyl group are substituted with fluorine atoms, with the hydroxyl group being particularly preferred.
Examples of the aliphatic hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be a monocyclic group or a polycyclic group, and can be appropriately selected from among a large number of groups proposed for use in, for example, resins for resist compositions for ArF excimer lasers.

When the cyclic group is a monocyclic group, the number of carbon atoms is more preferably 3 to 10. Among them, a structural unit derived from an acrylic acid ester containing an aliphatic monocyclic group containing a hydroxyl group, a cyano group, a carboxy group, or a hydroxyalkyl group in which some of the hydrogen atoms of the alkyl group are substituted with fluorine atoms. is more preferable. Examples of the monocyclic group include a group obtained by removing two or more hydrogen atoms from a monocycloalkane. Specifically, examples include groups obtained by removing two or more hydrogen atoms from a monocycloalkane such as cyclopentane, cyclohexane, and cyclooctane. Among these monocyclic groups, a group obtained by removing two or more hydrogen atoms from cyclopentane and a group obtained by removing two or more hydrogen atoms from cyclohexane are industrially preferred.

When the cyclic group is a polycyclic group, it is more preferable that the polycyclic group has 7 to 30 carbon atoms. Among them, a structural unit derived from an acrylic acid ester containing an aliphatic polycyclic group containing a hydroxyl group, a cyano group, a carboxy group, or a hydroxyalkyl group in which some of the hydrogen atoms of the alkyl group are substituted with fluorine atoms. is more preferable. Examples of the polycyclic group include groups obtained by removing two or more hydrogen atoms from bicycloalkanes, tricycloalkanes, tetracycloalkanes, and the like. Specifically, examples thereof include groups obtained by removing two or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, there are groups obtained by removing two or more hydrogen atoms from adamantane, groups obtained by removing two or more hydrogen atoms from norbornane, and groups obtained by removing two or more hydrogen atoms from tetracyclododecane. Industrially preferred.

As the structural unit (a3), any unit can be used without particular limitation as long as it contains a polar group-containing aliphatic hydrocarbon group.
The structural unit (a3) is a structural unit derived from an acrylic ester in which the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, and includes a polar group-containing aliphatic hydrocarbon group. Constituent units are preferred.
When the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, the structural unit (a3) may be derived from hydroxyethyl ester of acrylic acid. The structural units are preferred.
Further, as the structural unit (a3), when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a polycyclic group, the structural unit represented by the following formula (a3-1), the formula (a3 The structural unit represented by -2) and the structural unit represented by formula (a3-3) are listed as preferred; in the case of a monocyclic group, the structural unit represented by formula (a3-4) is These are listed as preferred.

［式中、Ｒは前記と同じであり、ｊは１～３の整数であり、ｋは１～３の整数であり、ｔ’は１～３の整数であり、ｌは０～５の整数であり、ｓは１～３の整数である。］

[In the formula, R is the same as above, j is an integer of 1 to 3, k is an integer of 1 to 3, t' is an integer of 1 to 3, and l is an integer of 0 to 5. and s is an integer from 1 to 3. ]

In formula (a3-1), j is preferably 1 or 2, more preferably 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, it is preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group.
It is preferable that j is 1, and it is particularly preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group.

In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5th or 6th position of the norbornyl group.

In formula (a3-3), t' is preferably 1. It is preferable that l is 1. Preferably, s is 1. In these, it is preferable that a 2-norbornyl group or a 3-norbornyl group is bonded to the terminal of the carboxy group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5 or 6 position of the norbornyl group.

In formula (a3-4), t' is preferably 1 or 2. It is preferable that l is 0 or 1. Preferably, s is 1. The fluorinated alkyl alcohol is preferably bonded to the 3 or 5 position of the cyclohexyl group.

The structural unit (a3) contained in the component (A1) may be one type or two or more types.
When the component (A1) has a structural unit (a3), the proportion of the structural unit (a3) is 1 to 30 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). It is preferably 2 to 25 mol%, more preferably 5 to 20 mol%.
By setting the ratio of the structural unit (a3) to a preferable lower limit value or more, the effect of containing the structural unit (a3) can be sufficiently obtained due to the above-mentioned effects, and by setting the ratio of the structural unit (a3) to a preferable upper limit value or less, other constituents It is possible to maintain a balance with the unit, and various lithography properties are improved.

≪Other constituent units≫
The component (A1) may have other structural units other than the above-mentioned structural units (a1), structural units (a2), and structural units (a3).
Other structural units include, for example, the structural unit (a10) containing a hydroxystyrene skeleton (described later), the structural unit (a9) represented by the general formula (a9-1), the structural unit derived from styrene (however, the structural unit (excluding those falling under (a10)), structural units (a4) containing an acid-nondissociable aliphatic cyclic group, and the like.

≪Structural unit containing hydroxystyrene skeleton (a10)≫
The structural unit (a10) is a structural unit represented by the following general formula (a10-1).

［式中、Ｒは、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｙａ^ｘ１は、単結合又は２価の連結基である。Ｗａ^ｘ１は、置換基を有してもよい芳香族炭化水素基である。ｎ_ａｘ１は、１以上の整数である。］

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ya ^x1 is a single bond or a divalent linking group. Wa ^x1 is an aromatic hydrocarbon group which may have a substituent. n _ax1 is an integer of 1 or more. ]

In the formula (a10-1), R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms.
The alkyl group having 1 to 5 carbon atoms in R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, methyl group, ethyl group, propyl group, isopropyl group, n- Examples include butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, and the like.
The halogenated alkyl group having 1 to 5 carbon atoms in R is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferred.
R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, a hydrogen atom, a methyl group, or a trifluoromethyl group is more preferred. Preferably, a hydrogen atom or a methyl group is more preferable, and a methyl group is particularly preferable.

In the formula (a10-1), Ya ^x1 is a single bond or a divalent linking group.
In the above chemical formula, the divalent linking group in ^Ya It is mentioned as.

・Divalent hydrocarbon group that may have a substituent:
When Ya ^x1 is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

...Aliphatic hydrocarbon group in Ya ^x1 An aliphatic hydrocarbon group means a hydrocarbon group without aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
Examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, and aliphatic hydrocarbon groups containing a ring in the structure.

...Linear or branched aliphatic hydrocarbon group The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and The number of carbon atoms is more preferably 1 to 4, and the number of carbon atoms is most preferably 1 to 3.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH ₂ -], an ethylene group [-(CH ₂ ) ₂ -], a trimethylene group [ -(CH ₂ ) ₃ -], tetramethylene group [-(CH ₂ ) ₄ -], pentamethylene group [-(CH ₂ ) ₅ -], and the like.
The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ - and other alkylmethylene groups; CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ )CH ₂ -, -C(CH ₂ Alkylethylene groups such as CH ₃ ) ₂ -CH ₂ -; -CH(CH ₃ )CH ₂ CH ₂ -, alkyltrimethylene groups such as -CH ₂ CH(CH ₃ )CH ₂ -; -CH(CH ₃ ) Examples include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ )CH ₂ CH ₂ -, and the like. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and a carbonyl group.

...Aliphatic hydrocarbon group containing a ring in its structure The aliphatic hydrocarbon group containing a ring in its structure is a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in its ring structure. (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), a group in which the above-mentioned cyclic aliphatic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group, a group in which the above-mentioned cyclic aliphatic Examples include a group in which a group hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those mentioned above.
The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms. Specifically, Examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and a carbonyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, or tert-butoxy group. More preferred are methoxy and ethoxy groups.
The halogen atom serving as the substituent is preferably a fluorine atom.
Examples of the halogenated alkyl group as the substituent include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms.
In the cyclic aliphatic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a substituent containing a heteroatom. As the substituent containing the hetero atom, -O-, -C(=O)-O-, -S-, -S(=O) ₂ -, and -S(=O) ₂ -O- are preferable.

...Aromatic hydrocarbon group in Ya ^x1 The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, even more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in substituents.
Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; Can be mentioned. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, the aromatic hydrocarbon group includes a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); an aromatic compound containing two or more aromatic rings; (For example, biphenyl, fluorene, etc.) with two hydrogen atoms removed; One hydrogen atom of the group (aryl group or heteroaryl group) with one hydrogen atom removed from the aromatic hydrocarbon ring or aromatic heterocycle. is substituted with an alkylene group. (a group in which one atom is removed), and the like. The alkylene group bonded to the aryl group or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon number.

The hydrogen atom of the aromatic hydrocarbon group may be substituted with a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group.
Examples of the alkoxy group, halogen atom, and halogenated alkyl group as the substituent include those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

・Divalent linking group containing a heteroatom:
When Ya ^x1 is a divalent linking group containing a heteroatom, the linking group is preferably -O-, -C(=O)-O-, -O-C(=O)-, - C(=O)-, -O-C(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H is an alkyl group, an acyl group ), -S-, -S(=O) ₂ -, -S(=O) ₂ -O-, general formula -Y ²¹ -O-Y ²² -, -Y ²¹ -O-, -Y ²¹ -C(=O)-O-, -C(=O)-O-Y ²¹ -, -[Y ²¹ -C(=O)-O] _m" -Y ²² -, -Y ²¹ -O-C(=O)-Y ²² - or -Y ²¹ -S(=O) ₂ -O-Y ²² - [wherein Y ²¹ and Y ²² are Each of them is a divalent hydrocarbon group which may independently have a substituent, O is an oxygen atom, and m'' is an integer from 0 to 3. ] etc.
The divalent linking group containing the heteroatom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=NH) In the case of -, H may be substituted with a substituent such as an alkyl group or acyl. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
General formula -Y ²¹ -O-Y ²² -, -Y ²¹ -O-, -Y ²¹ -C(=O)-O-, -C(=O)-O-Y ²¹ -, -[Y ²¹ - C(=O)-O] _m” -Y ²² -, -Y ²¹ -O-C(=O)-Y ²² - or -Y ²¹ -S(=O) ₂ -O-Y ²² -, Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent.The divalent hydrocarbon group is as described as the divalent linking group in Ya ^x1 above. The same ones as mentioned above (divalent hydrocarbon group which may have a substituent) can be mentioned.
^Y21 is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, even more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly a methylene group or an ethylene group. preferable.
Y ²² is preferably a linear or branched aliphatic hydrocarbon group, more preferably a methylene group, an ethylene group, or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
In the group represented by the formula -[Y ²¹ -C(=O)-O] _m" -Y ²² -, m" is an integer of 0 to 3, preferably an integer of 0 to 2, and 0 or 1 is more preferred, and 1 is particularly preferred. In other words, the group represented by the formula -[Y ²¹ -C(=O)-O] _m" -Y ²² - is the group represented by the formula -Y ²¹ -C(=O)-O-Y ²² - Groups are particularly preferred. Among these, groups represented by the formula -(CH ₂ ) _a' -C(=O)-O-(CH ₂ ) _b' - are preferred. In the formula, a' is 1 to is an integer of 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, even more preferably 1 or 2, and most preferably 1. b' is an integer of 1 to 10, and An integer of 1 to 5 is preferred, an integer of 1 to 5 is more preferred, 1 or 2 is even more preferred, and 1 is most preferred.

Among the above, Ya ^x1 includes a single bond, an ester bond [-C(=O)-O-, -OC(=O)-], an ether bond (-O-), a linear or branched chain It is preferably an alkylene group in the form of a shape, or a combination thereof, and a single bond or an ester bond [-C(=O)-O-, -O-C(=O)-] is more preferable.

In the formula (a10-1), Wa ^x1 is an aromatic hydrocarbon group which may have a substituent.
Examples of the aromatic hydrocarbon group in Wa ^x1 include a group obtained by removing (na _x1 +1) hydrogen atoms from an aromatic ring that may have a substituent. The aromatic ring here is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, even more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms; can be mentioned. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
In addition, the aromatic hydrocarbon group in Wa ^x1 is an aromatic compound containing an aromatic ring that may have two or more substituents (e.g. biphenyl, fluorene, etc.) by removing (n _ax1 +1) hydrogen atoms. Other groups may also be mentioned.
Among the above, Wa ^x1 is preferably a group obtained by removing ( _nax1 +1) hydrogen atoms from benzene, naphthalene, anthracene, or biphenyl, and a group obtained by removing ( _nax1 +1) hydrogen atoms from benzene or naphthalene. is more preferred, and a group obtained by removing (n _ax1 +1) hydrogen atoms from benzene is even more preferred.

The aromatic hydrocarbon group in Wa ^x1 may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, and a halogenated alkyl group. Examples of the alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent include those listed as the substituent for the cyclic aliphatic hydrocarbon group in Ya ^x1 . The substituent is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms, and an ethyl group or a methyl group. More preferred is a methyl group, with a methyl group being particularly preferred. The aromatic hydrocarbon group in Wa ^x1 preferably has no substituent.

In the formula (a10-1), n _ax1 is an integer of 1 or more, preferably an integer of 1 to 10, more preferably an integer of 1 to 5, even more preferably 1, 2 or 3, and 1 or 2 is Particularly preferred.

Specific examples of the structural unit (a10) represented by the formula (a10-1) are shown below.
In each of the following formulas, R ^α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

The number of structural units (a10) contained in the component (A1) may be one or more.
When the component (A1) has a structural unit (a10), the proportion of the structural unit (a10) in the component (A1) is as follows: It is preferably 5 to 80 mol%, more preferably 10 to 75 mol%, even more preferably 30 to 70 mol%, and particularly preferably 40 to 60 mol%.
By setting the ratio of the structural unit (a10) within the above-mentioned preferable range, the efficiency of supplying protons in the resist film increases and the developer solubility can be appropriately ensured, so that the effects of the present invention can be further obtained. It becomes easier.

Constituent unit (a4):
The structural unit (a4) is a structural unit containing an acid non-dissociable cyclic group. When the component (A1) has the structural unit (a4), the dry etching resistance of the photosensitive resin pattern to be formed is improved. Moreover, the hydrophobicity of the component (A1) increases.
The "acid non-dissociable cyclic group" in the structural unit (a4) means that when an acid is generated from the component (B) etc. described below due to exposure to light, it does not dissociate even if the acid acts and remains in the structural unit. It is a cyclic group that remains in .

As the structural unit (a4), for example, a structural unit derived from an acrylic ester containing an acid-nondissociable aliphatic cyclic group is preferable. Examples of the cyclic group include those exemplified in the case of the above-mentioned structural unit (a1), such as those for ArF excimer lasers, KrF excimer lasers (preferably ArF excimer lasers), etc. Many conventionally known resin components can be used as resin components of resist compositions. In particular, at least one selected from tricyclodecyl, adamantyl, tetracyclododecyl, isobornyl, and norbornyl groups is preferred from the standpoint of industrial availability. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.

Specific examples of the structural unit (a4) include those having the structures of the following general formulas (a4-1) to (a4-7).

［式中、Ｒ^αは、水素原子、メチル基またはトリフルオロメチル基を示す。］

[Wherein, R ^α represents a hydrogen atom, a methyl group, or a trifluoromethyl group. ]

Component (A1) may contain one type of structural unit (a4) or two or more types.
When the structural unit (a4) is contained in the component (A1), the proportion of the structural unit (a4) is preferably 1 to 30 mol% with respect to the total of all structural units constituting the component (A1), More preferably, it is 10 to 20 mol%.

Component (A1) is prepared by dissolving monomers for inducing each structural unit in a polymerization solvent, and initiating radical polymerization of, for example, azobisisobutyronitrile (AIBN), dimethyl azobisisobutyrate (for example, V-601, etc.). It can be manufactured by adding an agent and polymerizing it. Alternatively, the component (A1) may include a monomer that induces the structural unit (a1), a precursor monomer (monomer with a protected functional group) that induces a structural unit other than the structural unit (a1) as necessary, It can be produced by dissolving in a polymerization solvent, adding thereto a radical polymerization initiator as described above for polymerization, and then performing a deprotection reaction. In addition, during polymerization, for example, by using a chain transfer agent such as HS-CH ₂ -CH ₂ -CH ₂ -C(CF ₃ ) ₂ -OH in combination, -C(CF ₃ ) is added to the terminal. ₂ -OH group may be introduced. In this way, a copolymer into which a hydroxyalkyl group is introduced in which some of the hydrogen atoms of the alkyl group are replaced with fluorine atoms can reduce development defects and reduce LER (line edge roughness: unevenness of line sidewalls). It is effective in reducing

The weight average molecular weight (Mw) of the component (A1) (polystyrene conversion standard determined by gel permeation chromatography (GPC)) is not particularly limited, and is preferably from 1,000 to 50,000, more preferably from 2,000 to 30,000, and from 3,000 to 20,000 is more preferable.
When the Mw of component (A1) is below the preferable upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and when it is above the preferable lower limit of this range, it has good dry etching resistance. The cross-sectional shape of the resist pattern is good.
The degree of dispersion (Mw/Mn) of component (A1) is not particularly limited, and is preferably 1.0 to 4.0, more preferably 1.0 to 3.0, particularly preferably 1.1 to 2.0. . In addition, Mn indicates a number average molecular weight.

≪(B) Component≫
Component (B) is an acid generator component that generates acid upon exposure to light.
Component (B) is not particularly limited, and those that have been proposed as acid generators for chemically amplified resist compositions can be used.
Such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts; oxime sulfonate acid generators; diazomethane-based acid generators such as bisalkyl or bisarylsulfonyl diazomethanes and poly(bissulfonyl)diazomethanes; Acid generators include a wide variety of acid generators such as nitrobenzylsulfonate acid generators, iminosulfonate acid generators, and disulfone acid generators.

Examples of onium salt-based acid generators include compounds represented by the following general formula (b-1) (hereinafter also referred to as "component (b-1)"), and compounds represented by the general formula (b-2). Examples include a compound (hereinafter also referred to as "component (b-2)") or a compound represented by general formula (b-3) (hereinafter also referred to as "component (b-3)").

［式中、Ｒ^１０１及びＲ^１０４～Ｒ^１０８は、それぞれ独立に、置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、又は置換基を有していてもよい鎖状のアルケニル基である。Ｒ^１０４とＲ^１０５とは相互に結合して環構造を形成していてもよい。Ｒ^１０２は、炭素数１～５のフッ素化アルキル基又はフッ素原子である。Ｙ^１０１は、酸素原子を含む２価の連結基又は単結合である。Ｖ^１０１～Ｖ^１０３は、それぞれ独立に、単結合、アルキレン基又はフッ素化アルキレン基である。Ｌ^１０１～Ｌ^１０２は、それぞれ独立に、単結合又は酸素原子である。Ｌ^１０３～Ｌ^１０５は、それぞれ独立に、単結合、－ＣＯ－又は－ＳＯ_２－である。ｍは１以上の整数であって、Ｍ’^ｍ＋はｍ価のオニウムカチオンである。］

[In the formula, R ¹⁰¹ and R ¹⁰⁴ to R ¹⁰⁸ each independently represent a cyclic group that may have a substituent, a chain alkyl group that may have a substituent, or a substituent. It is a chain alkenyl group that may have. R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring structure. R ¹⁰² is a fluorinated alkyl group having 1 to 5 carbon atoms or a fluorine atom. Y ¹⁰¹ is a divalent linking group or a single bond containing an oxygen atom. V ¹⁰¹ to V ¹⁰³ each independently represent a single bond, an alkylene group, or a fluorinated alkylene group. L ¹⁰¹ to L ¹⁰² are each independently a single bond or an oxygen atom. L ¹⁰³ to L ¹⁰⁵ are each independently a single bond, -CO- or -SO ₂ -. m is an integer of 1 or more, and M' ^m+ is an m-valent onium cation. ]

{Anion part}
・Anion in component (b-1) In formula (b-1), R ¹⁰¹ is a cyclic group that may have a substituent, a chain alkyl group that may have a substituent, or It is a chain alkenyl group which may have a substituent.

Cyclic group that may have a substituent:
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. Aliphatic hydrocarbon group means a hydrocarbon group without aromaticity. Further, the aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

The aromatic hydrocarbon group in R ¹⁰¹ is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, even more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 10 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in substituents.
Specifically, the aromatic ring possessed by the aromatic hydrocarbon group in R ¹⁰¹ is benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms. Examples include aromatic heterocycles. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, the aromatic hydrocarbon group in R ¹⁰¹ includes a group in which one hydrogen atom is removed from the aromatic ring (aryl group: e.g., phenyl group, naphthyl group, etc.), a group in which one hydrogen atom in the aromatic ring is alkylene Examples include groups substituted with groups (eg, arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group). The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon number.

Examples of the cyclic aliphatic hydrocarbon group in R ¹⁰¹ include aliphatic hydrocarbon groups containing a ring in the structure.
The aliphatic hydrocarbon group containing a ring in its structure includes an alicyclic hydrocarbon group (a group in which one hydrogen atom is removed from an aliphatic hydrocarbon ring), and an alicyclic hydrocarbon group that is linear or branched. Examples thereof include a group bonded to the end of a chain aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among these, the polycycloalkanes include polycycloalkanes having polycyclic skeletons such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane; condensed ring systems such as cyclic groups having steroid skeletons; More preferred are polycycloalkanes having a polycyclic skeleton.

Among these, as the cyclic aliphatic hydrocarbon group for R ¹⁰¹ , a group obtained by removing one or more hydrogen atoms from a monocycloalkane or polycycloalkane is preferable, and a group obtained by removing one hydrogen atom from a polycycloalkane is more preferable. Preferably, an adamantyl group and a norbornyl group are particularly preferable, and an adamantyl group is most preferable.

The linear aliphatic hydrocarbon group that may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 4 carbon atoms. 1 to 3 are most preferred. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH ₂ -], an ethylene group [-(CH ₂ ) ₂ -], a trimethylene group [ -(CH ₂ ) ₃ -], tetramethylene group [-(CH ₂ ) ₄ -], pentamethylene group [-(CH ₂ ) ₅ -], and the like.
The branched aliphatic hydrocarbon group that may be bonded to the alicyclic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, and even more preferably 3 or 4 carbon atoms. 3 is most preferred. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ - and other alkylmethylene groups; CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ )CH ₂ -, -C(CH ₂ Alkylethylene groups such as CH ₃ ) ₂ -CH ₂ -; -CH(CH ₃ )CH ₂ CH ₂ -, alkyltrimethylene groups such as -CH ₂ CH(CH ₃ )CH ₂ -; -CH(CH ₃ ) Examples include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ )CH ₂ CH ₂ -, and the like. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

Furthermore, the cyclic hydrocarbon group in R ¹⁰¹ may contain a heteroatom such as a heterocycle. Specifically, lactone-containing cyclic groups represented by the above general formulas (a2-r-1) to (a2-r-7), respectively, and the above general formulas (a5-r-1) to (a5-r- -SO ₂ --containing cyclic groups represented by 4), and heterocyclic groups represented by the following chemical formulas (r-hr-1) to (r-hr-16), respectively. In the formula, * represents a bond bonded to Y ¹⁰¹ in formula (b-1).

Examples of the substituent in the cyclic group of R ¹⁰¹ include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, and the like.
The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group.
The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. and ethoxy groups are most preferred.
As the halogen atom as a substituent, a fluorine atom is preferable.
Examples of the halogenated alkyl group as a substituent include an alkyl group having 1 to 5 carbon atoms, such as a methyl group, ethyl group, propyl group, n-butyl group, and tert-butyl group, in which some or all of the hydrogen atoms are Examples include groups substituted with halogen atoms.
The carbonyl group as a substituent is a group that substitutes a methylene group (-CH ₂ -) constituting a cyclic hydrocarbon group.

The cyclic hydrocarbon group in R ¹⁰¹ may be a fused cyclic group containing a fused ring in which an aliphatic hydrocarbon ring and an aromatic ring are fused. Examples of the fused ring include one in which one or more aromatic rings are fused to a polycycloalkane having a polycyclic skeleton of a bridged ring system. Specific examples of the bridged ring polycycloalkanes include bicycloalkanes such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. The fused ring type is preferably a group containing a fused ring in which two or three aromatic rings are fused to a bicycloalkane, and a group containing a fused ring in which two or three aromatic rings are fused to a bicyclo[2.2.2]octane. More preferred are groups containing fused rings. Specific examples of the fused cyclic group for R ¹⁰¹ include those represented by the following formulas (r-br-1) to (r-br-2). In the formula, * represents a bond bonded to Y ¹⁰¹ in formula (b-1).

Examples of substituents that the fused cyclic group in R ¹⁰¹ may have include alkyl groups, alkoxy groups, halogen atoms, halogenated alkyl groups, hydroxyl groups, carbonyl groups, nitro groups, aromatic hydrocarbon groups, and aliphatic groups. Examples include cyclic hydrocarbon groups.
Examples of the alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as a substituent for the fused cyclic group include those listed as the substituent for the cyclic group in R ¹⁰¹ above.
Examples of the aromatic hydrocarbon group as a substituent for the fused cyclic group include a group in which one hydrogen atom is removed from the aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.), a group in which one hydrogen atom is removed from the aromatic ring, A group in which one of the groups is substituted with an alkylene group (for example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc.), the above Examples include heterocyclic groups represented by formulas (r-hr-1) to (r-hr-6), respectively.
Examples of the alicyclic hydrocarbon group as a substituent for the fused cyclic group include groups obtained by removing one hydrogen atom from a monocycloalkane such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tricyclodecane, and tetracycloalkane; A group obtained by removing one hydrogen atom from a polycycloalkane such as cyclododecane; a lactone-containing cyclic group represented by the above general formulas (a2-r-1) to (a2-r-7); a lactone-containing cyclic group represented by the above general formula -SO ₂ --containing cyclic groups represented by (a5-r-1) to (a5-r-4), respectively; represented by the formulas (r-hr-7) to (r-hr-16), respectively; Examples include heterocyclic groups such as

Chain alkyl group which may have a substituent:
The chain alkyl group for R ¹⁰¹ may be either linear or branched.
The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group. group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, henicosyl group, docosyl group, and the like.
The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, Examples include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

Chain alkenyl group which may have a substituent:
The chain alkenyl group for R ¹⁰¹ may be linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, even more preferably 2 to 4 carbon atoms, and is particularly preferred. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched alkenyl group include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, and 2-methylpropenyl group.
As the chain alkenyl group, among the above, a straight chain alkenyl group is preferable, a vinyl group and a propenyl group are more preferable, and a vinyl group is particularly preferable.

Examples of the substituent in the chain alkyl group or alkenyl group of R ¹⁰¹ include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and the cyclic group in R ¹⁰¹ above. Can be mentioned.

Among the above, R ¹⁰¹ is preferably a cyclic group that may have a substituent, and more preferably a cyclic hydrocarbon group that may have a substituent. More specifically, a phenyl group, a naphthyl group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane; each represented by the above general formulas (a2-r-1) to (a2-r-7) Lactone-containing cyclic group; -SO ₂ --containing cyclic groups represented by the above general formulas (a5-r-1) to (a5-r-4), etc. are preferred.

In formula (b-1), Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom.
When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, Y ¹⁰¹ may contain atoms other than the oxygen atom. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms.
Examples of divalent linking groups containing an oxygen atom include an oxygen atom (ether bond: -O-), an ester bond (-C(=O)-O-), and an oxycarbonyl group (-O-C(=O-). )-), amide bond (-C(=O)-NH-), carbonyl group (-C(=O)-), carbonate bond (-O-C(=O)-O-), etc. Oxygen atom-containing connecting group; a combination of the non-hydrocarbon oxygen atom-containing connecting group and an alkylene group, and the like. A sulfonyl group (-SO ₂ -) may be further linked to this combination. Examples of such divalent linking groups containing an oxygen atom include linking groups represented by the following general formulas (y-al-1) to (y-al-7), respectively.

［式中、Ｖ’^１０１は単結合または炭素数１～５のアルキレン基であり、Ｖ’^１０２は炭素数１～３０の２価の飽和炭化水素基である。］

[In the formula, V' ¹⁰¹ is a single bond or an alkylene group having 1 to 5 carbon atoms, and V' ¹⁰² is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms. ]

The divalent saturated hydrocarbon group in V' ¹⁰² is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and an alkylene group having 1 to 5 carbon atoms. It is more preferable that

The alkylene group in V' ¹⁰¹ and V' ¹⁰² may be a linear alkylene group or a branched alkylene group, with a linear alkylene group being preferred.
Specifically, the alkylene group in V' ¹⁰¹ and V' ¹⁰² is a methylene group [-CH ₂ -]; -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ -, etc. alkylmethylene groups; ethylene; Group [-CH ₂ CH ₂ -]; -CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ ) Alkylethylene group such as CH ₂ -; trimethylene group (n-propylene group) [-CH ₂ CH ₂ CH ₂ -]; -CH (CH ₃ ) CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) Alkyltrimethylene group such as CH ₂ -; tetramethylene group [-CH ₂ CH ₂ CH ₂ CH ₂ -]; -CH (CH ₃ ) CH ₂ CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ Examples include alkyltetramethylene groups such as CH ₂ -; pentamethylene groups [-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ -], and the like.
Further, a part of the methylene group in the alkylene group in V' ¹⁰¹ or V' ¹⁰² may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is a cyclic aliphatic hydrocarbon group (a monocyclic aliphatic hydrocarbon group, a polycyclic aliphatic hydrocarbon group) represented by Ra' ³ in the above formula (a1-r-1). A divalent group obtained by removing one hydrogen atom from ) is preferred, and a cyclohexylene group, a 1,5-adamantylene group, or a 2,6-adamantylene group is more preferred.

Y ¹⁰¹ is preferably a divalent linking group containing an ester bond or a divalent linking group containing an ether bond, each represented by the above formulas (y-al-1) to (y-al-5). A linking group is more preferred.

In formula (b-1), V ¹⁰¹ is a single bond, an alkylene group, or a fluorinated alkylene group. The alkylene group and fluorinated alkylene group in V ¹⁰¹ preferably have 1 to 4 carbon atoms. The fluorinated alkylene group in V ¹⁰¹ includes a group in which some or all of the hydrogen atoms of the alkylene group in V ¹⁰¹ are substituted with fluorine atoms. Among these, V ¹⁰¹ is preferably a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms.

In formula (b-1), R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R ¹⁰² is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

Specific examples of the anion moiety represented by the above formula (b-1) include, for example, when Y ¹⁰¹ is a single bond, fluorinated alkyl sulfonate anions such as trifluoromethanesulfonate anions and perfluorobutanesulfonate anions. ; When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, examples thereof include anions represented by any of the following formulas (an-1) to (an-3).

［式中、Ｒ”^１０１は、置換基を有してもよい脂肪族環式基、上記の化学式（ｒ－ｈｒ－１）～（ｒ－ｈｒ－６）でそれぞれ表される１価の複素環式基、前記式（ｒ－ｂｒ－１）又（ｒ－ｂｒ－２）で表される縮合環式基、又は置換基を有してもよい鎖状のアルキル基である。Ｒ”^１０２は、置換基を有してもよい脂肪族環式基、前記式（ｒ－ｂｒ－１）又（ｒ－ｂｒ－２）で表される縮合環式基、前記一般式（ａ２－ｒ－１）、（ａ２－ｒ－３）～（ａ２－ｒ－７）でそれぞれ表されるラクトン含有環式基、又は前記一般式（ａ５－ｒ－１）～（ａ５－ｒ－４）でそれぞれ表される－ＳＯ_２－含有環式基である。Ｒ”^１０３は、置換基を有してもよい芳香族環式基、置換基を有してもよい脂肪族環式基、又は置換基を有してもよい鎖状のアルケニル基である。Ｖ”^１０１は、単結合、炭素数１～４のアルキレン基、又は炭素数１～４のフッ素化アルキレン基である。Ｒ^１０２は、フッ素原子又は炭素数１～５のフッ素化アルキル基である。ｖ”はそれぞれ独立に０～３の整数であり、ｑ”はそれぞれ独立に０～２０の整数であり、ｎ”は０または１である。］

[In the formula, ^R''101 is an aliphatic cyclic group which may have a substituent, a monovalent heterocyclic group represented by the above chemical formulas (r-hr-1) to (r-hr-6), respectively. A cyclic group, a fused cyclic group represented by the above formula (r-br-1) or (r-br-2), or a chain alkyl group that may have a substituent.R" ¹⁰² is an aliphatic cyclic group which may have a substituent, a fused cyclic group represented by the above formula (r-br-1) or (r-br-2), and the above general formula (a2-r- 1), a lactone-containing cyclic group represented by (a2-r-3) to (a2-r-7), respectively, or a lactone-containing cyclic group represented by the general formulas (a5-r-1) to (a5-r-4), respectively. is a -SO ₂ -containing cyclic group represented by ^R''103 is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain alkenyl group which may have a substituent. V" ¹⁰¹ is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. v'' are each independently an integer from 0 to 3, q'' are each independently an integer from 0 to 20, and n'' is 0 or 1.]

The aliphatic cyclic group which may have a substituent for R'' ¹⁰¹ , R'' ¹⁰² and R'' ¹⁰³ is the group exemplified as the cyclic aliphatic hydrocarbon group for R ¹⁰¹ in formula (b-1) above. It is preferable that the substituent is the same as the substituent that may substitute the cyclic aliphatic hydrocarbon group in R ¹⁰¹ in the formula (b-1).

The aromatic cyclic group which may have a substituent in R'' ¹⁰³ may be the group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group in R ¹⁰¹ in formula (b-1) above. Preferably. Examples of the substituent include the same substituents that may substitute the aromatic hydrocarbon group in R ¹⁰¹ in the formula (b-1).

The chain alkyl group which may have a substituent in R" ¹⁰¹ is preferably the group exemplified as the chain alkyl group in R ¹⁰¹ in formula (b-1) above.
The chain alkenyl group which may have a substituent in R'' ¹⁰³ is preferably the group exemplified as the chain alkenyl group in R ¹⁰¹ in formula (b-1) above.

・Anion in component (b-2) In formula (b-2), R ¹⁰⁴ and R ¹⁰⁵ are each independently a cyclic group that may have a substituent, or a cyclic group that may have a substituent. It is a chain alkyl group or a chain alkenyl group which may have a substituent, and examples thereof include those similar to R ¹⁰¹ in formula (b-1). However, R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring.
R ¹⁰⁴ and R ¹⁰⁵ are preferably a chain alkyl group that may have a substituent, and are a linear or branched alkyl group or a linear or branched fluorinated alkyl group. It is more preferable.
The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and even more preferably 1 to 3 carbon atoms. The smaller the number of carbon atoms in the chain alkyl group of R ¹⁰⁴ and R ¹⁰⁵ is, within the above range, the better, for reasons such as good solubility in a resist solvent. In addition, in the chain alkyl groups of R ¹⁰⁴ and R ¹⁰⁵ , the greater the number of hydrogen atoms substituted with fluorine atoms, the stronger the acid strength, and the higher the resistance to high energy light and electron beams of 250 nm or less. This is preferable because it improves transparency. The proportion of fluorine atoms in the chain alkyl group, that is, the fluorination rate, is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all hydrogen atoms are substituted with fluorine atoms. It is a perfluoroalkyl group.
In formula (b-2), V ¹⁰² and V ¹⁰³ are each independently a single bond, an alkylene group, or a fluorinated alkylene group, and each of them is the same as V ¹⁰¹ in formula (b-1). Can be mentioned.
In formula (b-2), L ¹⁰¹ and L ¹⁰² are each independently a single bond or an oxygen atom.

・Anion in component (b-3) In formula (b-3), R ¹⁰⁶ to R ¹⁰⁸ are each independently a cyclic group that may have a substituent, or a cyclic group that may have a substituent. It is a chain alkyl group or a chain alkenyl group which may have a substituent, and examples thereof include those similar to R ¹⁰¹ in formula (b-1).
In formula (b-3), L ¹⁰³ to L ¹⁰⁵ are each independently a single bond, -CO- or -SO ₂ -.

Among the above, as the anion moiety of component (B), the anion in component (b-1) is preferable. Among these, anions represented by any of the above general formulas (an-1) to (an-3) are more preferable, and anions represented by any of the general formulas (an-1) or (an-2) are more preferable. Anions are more preferred, and anions represented by general formula (an-2) are particularly preferred.

{Cation part}
In the formula (b-1), formula (b-2), and formula (b-3), M' ^m+ represents an m-valent onium cation. Among these, sulfonium cations and iodonium cations are preferred.
m is an integer of 1 or more.

Preferred cation moieties ((M' ^m+ ) _1/m ) include organic cations represented by the following general formulas (ca-1) to (ca-5), respectively.

［式中、Ｒ^２０１～Ｒ^２０７、およびＲ^２１１～Ｒ^２１２は、それぞれ独立に置換基を有してもよいアリール基、アルキル基またはアルケニル基を表す。Ｒ^２０１～Ｒ^２０３、Ｒ^２０６～Ｒ^２０７、Ｒ^２１１～Ｒ^２１２は、相互に結合して式中のイオウ原子と共に環を形成してもよい。Ｒ^２０８～Ｒ^２０９は、それぞれ独立に水素原子または炭素数１～５のアルキル基を表す。Ｒ^２１０は、置換基を有してもよいアリール基、置換基を有してもよいアルキル基、置換基を有してもよいアルケニル基、又は置換基を有してもよいＳＯ_２－含有環式基である。Ｌ^２０１は、－Ｃ（＝Ｏ）－または－Ｃ（＝Ｏ）－Ｏ－を表す。Ｙ^２０１は、それぞれ独立に、アリーレン基、アルキレン基またはアルケニレン基を表す。ｘは１または２である。Ｗ^２０１は（ｘ＋１）価の連結基を表す。］

[In the formula, R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² each independently represent an aryl group, an alkyl group, or an alkenyl group that may have a substituent. R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , and R ²¹¹ to R ²¹² may be bonded to each other to form a ring together with the sulfur atom in the formula. R ²⁰⁸ to R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R ²¹⁰ is an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or an SO ₂ -containing group which may have a substituent It is a cyclic group. L ²⁰¹ represents -C(=O)- or -C(=O)-O-. Y ²⁰¹ each independently represents an arylene group, an alkylene group or an alkenylene group. x is 1 or 2. W ²⁰¹ represents a (x+1)-valent linking group. ]

In the above general formulas (ca-1) to (ca-5), the aryl group in R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² includes an unsubstituted aryl group having 6 to 20 carbon atoms, Phenyl group and naphthyl group are preferred.
The alkyl groups for R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² are preferably chain or cyclic alkyl groups having 1 to 30 carbon atoms.
The alkenyl groups in R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² preferably have 2 to 10 carbon atoms.
Examples of the substituents that R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, and the following. Examples include groups represented by the general formulas (car-r-1) to (car-r-7), respectively.

［式中、Ｒ’^２０１は、それぞれ独立に、水素原子、置換基を有してもよい環式基、置換基を有してもよい鎖状のアルキル基、又は置換基を有してもよい鎖状のアルケニル基である。］

[In the formula, R' ²⁰¹ is each independently a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkyl group which may have a substituent. It is a good chain alkenyl group. ]

Cyclic group that may have a substituent:
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. Aliphatic hydrocarbon group means a hydrocarbon group without aromaticity. Further, the aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

The aromatic hydrocarbon group in R' ²⁰¹ is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, even more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and 6 to 30 carbon atoms. 10 is most preferred. However, the number of carbon atoms does not include the number of carbon atoms in substituents.
Specifically, the aromatic ring possessed by the aromatic hydrocarbon group in R' ²⁰¹ is benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or a ring in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms. and aromatic heterocycles. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, the aromatic hydrocarbon group in R' ²⁰¹ includes a group in which one hydrogen atom is removed from the aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.), a group in which one of the hydrogen atoms in the aromatic ring is alkylene Examples include groups substituted with groups (eg, arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group). The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon number.

Examples of the cyclic aliphatic hydrocarbon group for R' ²⁰¹ include aliphatic hydrocarbon groups containing a ring in the structure.
The aliphatic hydrocarbon group containing a ring in its structure includes an alicyclic hydrocarbon group (a group in which one hydrogen atom is removed from an aliphatic hydrocarbon ring), and an alicyclic hydrocarbon group that is linear or branched. Examples include a group bonded to the end of a chain aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among these, the polycycloalkanes include polycycloalkanes having polycyclic skeletons such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane; condensed ring systems such as cyclic groups having steroid skeletons; More preferred are polycycloalkanes having a polycyclic skeleton.

Among these, as the cyclic aliphatic hydrocarbon group for R' ²⁰¹ , a group obtained by removing one or more hydrogen atoms from a monocycloalkane or a polycycloalkane is preferable, and a group obtained by removing one hydrogen atom from a polycycloalkane is preferable. More preferred are adamantyl groups and norbornyl groups, and most preferred are adamantyl groups.

The linear or branched aliphatic hydrocarbon group that may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and The number of carbon atoms is more preferably 1 to 4, and the number of carbon atoms is particularly preferably 1 to 3.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH ₂ -], an ethylene group [-(CH ₂ ) ₂ -], a trimethylene group [ -(CH ₂ ) ₃ -], tetramethylene group [-(CH ₂ ) ₄ -], pentamethylene group [-(CH ₂ ) ₅ -], and the like.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ - and other alkylmethylene groups; CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ )CH ₂ -, -C(CH ₂ Alkylethylene groups such as CH ₃ ) ₂ -CH ₂ -; -CH(CH ₃ )CH ₂ CH ₂ -, alkyltrimethylene groups such as -CH ₂ CH(CH ₃ )CH ₂ -; -CH(CH ₃ ) Examples include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ )CH ₂ CH ₂ -, and the like. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

Furthermore, the cyclic hydrocarbon group in R' ²⁰¹ may contain a heteroatom such as a heterocycle. Specifically, lactone-containing cyclic groups represented by the above general formulas (a2-r-1) to (a2-r-7), respectively, and the above general formulas (a5-r-1) to (a5-r- -SO ₂ --containing cyclic groups represented by 4), and heterocyclic groups represented by the above chemical formulas (r-hr-1) to (r-hr-16), respectively.

Examples of the substituent in the cyclic group of R' ²⁰¹ include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, and the like.
The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group.
The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. and ethoxy groups are most preferred.
As the halogen atom as a substituent, a fluorine atom is preferable.
Examples of the halogenated alkyl group as a substituent include an alkyl group having 1 to 5 carbon atoms, such as a methyl group, ethyl group, propyl group, n-butyl group, and tert-butyl group, in which some or all of the hydrogen atoms are Examples include groups substituted with halogen atoms.
The carbonyl group as a substituent is a group that substitutes a methylene group (-CH ₂ -) constituting a cyclic hydrocarbon group.

Chain-like alkyl group which may have a substituent:
The chain alkyl group of R' ²⁰¹ may be either linear or branched.
The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms.
The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, Examples include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

Chain alkenyl group which may have a substituent:
The chain alkenyl group for R' ²⁰¹ may be either linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, and preferably has 2 to 4 carbon atoms. is more preferable, and a carbon number of 3 is particularly preferable. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched alkenyl group include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, and 2-methylpropenyl group.
As the chain alkenyl group, among the above, a straight chain alkenyl group is preferable, a vinyl group and a propenyl group are more preferable, and a vinyl group is particularly preferable.

Examples of substituents on the chain alkyl group or alkenyl group of R' ²⁰¹ include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and the cyclic group of R' ²⁰¹ above. etc.

The cyclic group that may have a substituent, the chain alkyl group that may have a substituent, or the chain alkenyl group that may have a substituent for ^R'201 is other than those mentioned above. , as a cyclic group that may have a substituent or a chain alkyl group that may have a substituent, those similar to the acid-dissociable group represented by the above formula (a1-r-2) can also be mentioned.

Among these, R' ²⁰¹ is preferably a cyclic group that may have a substituent, and more preferably a cyclic hydrocarbon group that may have a substituent. More specifically, for example, a phenyl group, a naphthyl group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane; -SO ₂ -containing cyclic groups represented by the general formulas (a5-r-1) to (a5-r-4), etc. are preferred.

In the above general formulas (ca-1) to (ca-5), R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , and R ²¹¹ to R ²¹² are bonded to each other to form a ring with the sulfur atom in the formula. In this case, a hetero atom such as a sulfur atom, an oxygen atom, a nitrogen atom, a carbonyl group, -SO-, -SO ₂ -, -SO ₃ -, -COO-, -CONH- or -N(R _N )-( They may be bonded via a functional group such as R _N is an alkyl group having 1 to 5 carbon atoms. As for the ring to be formed, one ring in the formula containing a sulfur atom in its ring skeleton is preferably a 3- to 10-membered ring, particularly a 5- to 7-membered ring. preferable. Specific examples of the ring formed include a thiophene ring, a thiazole ring, a benzothiophene ring, a thianthrene ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthrene ring, a phenoxathiine ring, and a tetrahydrocarbon ring. Examples include a thiophenium ring and a tetrahydrothiopyranium ring.

R ²⁰⁸ to R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and when they are an alkyl group, they are bonded to each other. It may form a ring.

R ²¹⁰ is an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or an SO ₂ -containing group which may have a substituent It is a cyclic group.
Examples of the aryl group for R ²¹⁰ include unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred.
The alkyl group for R ²¹⁰ is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group for R ²¹⁰ preferably has 2 to 10 carbon atoms.
The SO ₂ -containing cyclic group which may have a substituent in R ²¹⁰ is preferably a "-SO ₂ -containing polycyclic group", which is represented by the above general formula (a5-r-1). groups are more preferred.

Y ²⁰¹ each independently represents an arylene group, an alkylene group, or an alkenylene group.
Examples of the arylene group in Y ²⁰¹ include a group obtained by removing one hydrogen atom from the aryl group exemplified as the aromatic hydrocarbon group in R ¹⁰¹ in the above formula (b-1).
Examples of the alkylene group and alkenylene group in Y ²⁰¹ include groups obtained by removing one hydrogen atom from the groups exemplified as the chain alkyl group and chain alkenyl group in R ¹⁰¹ in the above formula (b-1). .

In the formula (ca-4), x is 1 or 2.
W ²⁰¹ is a (x+1)-valent, ie, divalent or trivalent, linking group.
The divalent linking group in W ²⁰¹ is preferably a divalent hydrocarbon group which may have a substituent, and a divalent hydrocarbon group having a substituent similar to Ya ²¹ in the above general formula (a2-1) is preferable. Examples include divalent hydrocarbon groups which may be optional. The divalent linking group in W ²⁰¹ may be linear, branched, or cyclic, and is preferably cyclic. Among these, a group in which two carbonyl groups are combined at both ends of an arylene group is preferable. Examples of the arylene group include a phenylene group and a naphthylene group, with a phenylene group being particularly preferred.
Examples of the trivalent linking group in W ²⁰¹ include a group obtained by removing one hydrogen atom from the divalent linking group in W ²⁰¹ , a group in which the divalent linking group is further bonded to the divalent linking group, etc. Can be mentioned. The trivalent linking group in W ²⁰¹ is preferably a group in which two carbonyl groups are bonded to an arylene group.

Specific examples of suitable cations represented by the formula (ca-1) include cations represented by the following chemical formulas (ca-1-1) to (ca-1-70).

［式中、ｇ１、ｇ２、ｇ３は繰返し数を示し、ｇ１は１～５の整数であり、ｇ２は０～２０の整数であり、ｇ３は０～２０の整数である。］

[In the formula, g1, g2, and g3 indicate the number of repetitions, g1 is an integer of 1 to 5, g2 is an integer of 0 to 20, and g3 is an integer of 0 to 20. ]

［式中、Ｒ”^２０１は水素原子又は置換基であって、該置換基としては前記Ｒ^２０１～Ｒ^２０７、およびＲ^２１０～Ｒ^２１２が有していてもよい置換基として挙げたものと同様である。］

[In the formula, R'' ²⁰¹ is a hydrogen atom or a substituent, and the substituent is the same as the substituents that R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have. ]

Specific examples of suitable cations represented by formula (ca-2) include diphenyliodonium cations, bis(4-tert-butylphenyl)iodonium cations, and the like.

Specific examples of suitable cations represented by the above formula (ca-3) include cations represented by the following formulas (ca-3-1) to (ca-3-6).

Specific examples of suitable cations represented by the above formula (ca-4) include cations represented by the following formulas (ca-4-1) to (ca-4-2).

Specific examples of suitable cations represented by the above formula (ca-5) include cations represented by the following general formulas (ca-5-1) to (ca-5-3).

Among the above, the cation moiety ((M' ^m+ ) _1/m ) is preferably a cation represented by the general formula (ca-1).

In the resist composition in this embodiment, the component (B) may be used alone or in combination of two or more.
When the resist composition contains component (B), the content of component (B) in the resist composition is preferably less than 50 parts by mass, and 1 to 40 parts by mass, based on 100 parts by mass of component (A). is more preferable, and 5 to 25 parts by mass is even more preferable.
By setting the content of component (B) within the above-mentioned preferred range, pattern formation can be sufficiently performed. Further, when each component of the resist composition is dissolved in an organic solvent, a uniform solution is easily obtained, and the resist composition has good storage stability, which is preferable.

≪Organic solvent component (S)≫
The resist composition in this embodiment can be manufactured by dissolving a resist material in an organic solvent component (hereinafter referred to as "component (S)").
The component (S) may be any one as long as it can dissolve each component to be used and form a uniform solution, and any one can be used as appropriate from among those conventionally known as solvents for chemically amplified resist compositions. It can be used selectively.
As the component (S), for example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; ethylene glycol, diethylene glycol, propylene glycol , polyhydric alcohols such as dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate, the polyhydric alcohols or having the ester bond. Derivatives of polyhydric alcohols such as monoalkyl ethers of compounds such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, or compounds having ether bonds such as monophenyl ether [Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) are preferred]; cyclic ethers such as dioxane, methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate , methyl methoxypropionate, ethyl ethoxypropionate and other esters; anisole, ethylbenzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenethol, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, Examples include aromatic organic solvents such as xylene, cymene, and mesitylene, dimethyl sulfoxide (DMSO), and the like.
In the resist composition of this embodiment, the (S) component may be used alone or as a mixed solvent of two or more. Among these, PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferred.

Further, as the component (S), a mixed solvent of PGMEA and a polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined taking into consideration the compatibility between PGMEA and the polar solvent, but is preferably 1:9 to 9:1, more preferably 2:8 to 8:2. It is preferable to keep it within the range.
More specifically, when blending EL or cyclohexanone as a polar solvent, the mass ratio of PGMEA:EL or cyclohexanone is preferably 1:9 to 9:1, more preferably 2:8 to 8:2. . Further, when PGME is blended as a polar solvent, the mass ratio of PGMEA:PGME is preferably 1:9 to 9:1, more preferably 2:8 to 8:2, and even more preferably 3:7 to 7: It is 3. Furthermore, a mixed solvent of PGMEA, PGME, and cyclohexanone is also preferred.
In addition, as component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, the mass ratio of the former to the latter is preferably 70:30 to 95:5.
The amount of component (S) to be used is not particularly limited, and is appropriately set at a concentration that allows coating on a substrate, etc., depending on the thickness of the coating film. Generally, component (S) is used so that the solid content concentration of the resist composition is in the range of 0.1 to 20% by weight, preferably 0.2 to 15% by weight.

The resist composition in this embodiment may further contain components other than the above-mentioned components (A), (B), and (S). Examples of such components include component (D), component (E), and component (F) shown below.

≪(D) Component≫
The resist composition in this embodiment further contains a base component (hereinafter referred to as "component (D)") in addition to component (A) or in addition to component (A) and component (B). You can. Component (D) acts as a quencher (acid diffusion control agent) that traps acid generated by exposure in the resist composition.
Component (D) may be a photodegradable base (D1) that decomposes upon exposure and loses its acid diffusion controllability (hereinafter referred to as "component (D1)"), and may contain any other components that do not fall under the component (D1). It may be a nitrogen organic compound (D2) (hereinafter referred to as "component (D2)").
By using a resist composition containing component (D), it is possible to further improve the contrast between exposed and unexposed areas of the resist film when forming a resist pattern.

- Regarding component (D1) By using a resist composition containing component (D1), when forming a resist pattern, the contrast between exposed areas and unexposed areas of the resist film can be further improved.
Component (D1) is not particularly limited as long as it decomposes upon exposure and loses acid diffusion control properties, and may be a compound represented by the following general formula (d1-1) (hereinafter referred to as "component (d1-1)"). ), a compound represented by the following general formula (d1-2) (hereinafter referred to as "(d1-2) component"), and a compound represented by the following general formula (d1-3) (hereinafter referred to as "(d1-2) component"). 3) One or more compounds selected from the group consisting of "components" are preferred.
Components (d1-1) to (d1-3) do not act as quenchers because they decompose in the exposed areas of the resist film and lose their acid diffusion control properties (basicity), but they do not act as quenchers in the unexposed areas of the resist film. Acts as a char.

［式中、Ｒｄ^１～Ｒｄ^４は置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、又は置換基を有していてもよい鎖状のアルケニル基である。但し、式（ｄ１－２）中のＲｄ^２における、Ｓ原子に隣接する炭素原子にはフッ素原子は結合していないものとする。Ｙｄ^１は単結合又は２価の連結基である。ｍは１以上の整数であって、Ｍ^ｍ＋はそれぞれ独立にｍ価の有機カチオンである。］

[In the formula, Rd ¹ to Rd ⁴ are a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkyl group which may have a substituent. is an alkenyl group. However, it is assumed that no fluorine atom is bonded to the carbon atom adjacent to the S atom in Rd ² in formula (d1-2). Yd ¹ is a single bond or a divalent linking group. m is an integer of 1 or more, and M ^m+ are each independently an m-valent organic cation. ]

{(d1-1) component}
・Anion moiety In formula (d1-1), Rd ¹ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. is an optional chain alkenyl group, and examples thereof include the same groups as R' ²⁰¹ above.
Among these, Rd ¹ is an aromatic hydrocarbon group that may have a substituent, an aliphatic cyclic group that may have a substituent, or an aliphatic cyclic group that may have a substituent. A chain alkyl group is preferred. Examples of substituents that these groups may have include a hydroxyl group, an oxo group, an alkyl group, an aryl group, a fluorine atom, a fluorinated alkyl group, and the above general formulas (a2-r-1) to (a2-r- Examples include a lactone-containing cyclic group represented by 7), an ether bond, an ester bond, or a combination thereof. When an ether bond or an ester bond is included as a substituent, it may be via an alkylene group, and the substituent in this case is represented by the above formulas (y-al-1) to (y-al-5), respectively. A linking group is preferred.
Preferred examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and a polycyclic structure containing a bicyclooctane skeleton (a polycyclic structure consisting of a bicyclooctane skeleton and other ring structures).
The aliphatic cyclic group is more preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
The chain alkyl group preferably has 1 to 10 carbon atoms, and specifically includes a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, Straight chain alkyl groups such as nonyl group and decyl group; 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group Examples include branched alkyl groups such as 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

When the chain alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the number of carbon atoms in the fluorinated alkyl group is preferably 1 to 11, more preferably 1 to 8, and 1 -4 is more preferred. The fluorinated alkyl group may contain atoms other than fluorine atoms. Examples of atoms other than fluorine atoms include oxygen atoms, sulfur atoms, and nitrogen atoms.
Rd ¹ is preferably a fluorinated alkyl group in which some or all of the hydrogen atoms constituting the linear alkyl group are substituted with fluorine atoms; A fluorinated alkyl group (linear perfluoroalkyl group) in which all fluorine atoms are substituted is particularly preferred.

Preferred specific examples of the anion moiety of component (d1-1) are shown below.

-Cation part In formula (d1-1), M ^m+ is an m-valent organic cation.
As the organic cation of M ^m+ , the same cations as the cations represented by the above general formulas (ca-1) to (ca-4) are preferably mentioned, and the cations shown by the above general formula (ca-1) are preferably mentioned. Cations are more preferred, and cations represented by the formulas (ca-1-1) to (ca-1-78) and (ca-1-101) to (ca-1-149) are even more preferred.
Component (d1-1) may be used alone or in combination of two or more.

{(d1-2) component}
・Anion moiety In formula (d1-2), Rd ² is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group that may be optional, and examples include the same groups as R' ²⁰¹ above.
However, it is assumed that no fluorine atom is bonded to the carbon atom adjacent to the S atom in Rd ² (not substituted with fluorine). As a result, the anion of the component (d1-2) becomes an appropriately weak acid anion, and the quenching ability of the component (D) is improved.
Rd ² is preferably a chain alkyl group that may have a substituent or an aliphatic cyclic group that may have a substituent. The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 3 to 10 carbon atoms. Examples of aliphatic cyclic groups include a group obtained by removing one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. (which may have a substituent); one group from camphor, etc. It is more preferable to use a group excluding any of the above hydrogen atoms.
The hydrocarbon group of Rd ² may have a substituent, and examples of the substituent include the hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group) of Rd ¹ of the above formula (d1-1). , chain alkyl group) may be included.

Preferred specific examples of the anion moiety of component (d1-2) are shown below.

-Cation part In formula (d1-2), M ^m+ is an m-valent organic cation, and is the same as M ^m+ in formula (d1-1) above.
Component (d1-2) may be used alone or in combination of two or more.

{(d1-3) component}
・Anion part In formula (d1-3), Rd ³ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. Examples of the chain alkenyl group include those similar to R' ²⁰¹ above, and a cyclic group containing a fluorine atom, a chain alkyl group, or a chain alkenyl group is preferable. Among these, a fluorinated alkyl group is preferred, and the same fluorinated alkyl group as Rd ¹ above is more preferred.

In formula (d1-3), Rd ⁴ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group, and examples include those similar to R' ²⁰¹ above.
Among these, alkyl groups, alkoxy groups, alkenyl groups, and cyclic groups which may have substituents are preferable.
The alkyl group in Rd ⁴ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group. , tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. A portion of the hydrogen atoms of the alkyl group of Rd ⁴ may be substituted with a hydroxyl group, a cyano group, or the like.
The alkoxy group in Rd ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms, and specific examples of the alkoxy group having 1 to 5 carbon atoms include methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n- Examples include butoxy group and tert-butoxy group. Among them, methoxy group and ethoxy group are preferred.

Examples of the alkenyl group for Rd ⁴ include the same alkenyl groups as for R' ²⁰¹ above, and vinyl group, propenyl group (allyl group), 1-methylpropenyl group, and 2-methylpropenyl group are preferable. These groups may further have an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms as a substituent.

Examples of the cyclic group in Rd ⁴ include the same cyclic groups as in R' ²⁰¹ above, including one or more cycloalkanes such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. An alicyclic group from which a hydrogen atom has been removed, or an aromatic group such as a phenyl group or a naphthyl group is preferable. When Rd ⁴ is an alicyclic group, the resist composition dissolves well in an organic solvent, resulting in good lithography properties. Further, when Rd ⁴ is an aromatic group, the resist composition has excellent light absorption efficiency and good sensitivity and lithography properties in lithography using EUV or the like as an exposure light source.

In formula (d1-3), Yd ¹ is a single bond or a divalent linking group.
The divalent linking group in Yd ¹ is not particularly limited, but includes divalent hydrocarbon groups (aliphatic hydrocarbon groups, aromatic hydrocarbon groups) that may have substituents, and 2 containing heteroatoms. Examples include a valent linking group and the like. Each of these includes a divalent hydrocarbon group which may have a substituent, and a hetero atom, as mentioned in the explanation of the divalent linking group in Ya ²¹ in formula (a2-1) above. Examples include those similar to the divalent linking group.
Yd ¹ is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. The alkylene group is more preferably a linear or branched alkylene group, and even more preferably a methylene group or an ethylene group.

Preferred specific examples of the anion moiety of component (d1-3) are shown below.

-Cation part In formula (d1-3), M ^m+ is an m-valent organic cation, and is the same as M ^m+ in formula (d1-1) above.
Component (d1-3) may be used alone or in combination of two or more.

As the component (D1), any one of the components (d1-1) to (d1-3) described above may be used alone, or two or more thereof may be used in combination.
When the resist composition contains component (D1), the content of component (D1) in the resist composition is preferably 0.5 to 20 parts by mass, and 1 to 20 parts by mass, based on 100 parts by mass of component (A). It is more preferably 15 parts by weight, and even more preferably 5 to 10 parts by weight.
When the content of the component (D1) is at least the preferable lower limit, particularly good lithography properties and resist pattern shape are likely to be obtained. On the other hand, when it is below the upper limit, sensitivity can be maintained well and throughput is also excellent.

(D1) Method for producing component:
The method for producing the components (d1-1) and (d1-2) is not particularly limited, and they can be produced by known methods.
Furthermore, the method for producing component (d1-3) is not particularly limited, and is produced, for example, in the same manner as the method described in US2012-0149916.

- Regarding component (D2) The acid diffusion control agent component may contain a nitrogen-containing organic compound component (hereinafter referred to as "component (D2)") that does not correspond to component (D1) above.
The component (D2) is not particularly limited as long as it acts as an acid diffusion control agent and does not fall under the component (D1), and any known components may be used. Among these, aliphatic amines are preferred, and among these, secondary aliphatic amines and tertiary aliphatic amines are particularly preferred.
The aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic group preferably has 1 to 12 carbon atoms.
Examples of aliphatic amines include amines (alkyl amines or alkyl alcohol amines) or cyclic amines in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms.
Specific examples of alkyl amines and alkyl alcohol amines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, and n-decylamine; diethylamine, di-n-propylamine, di- -Dialkylamines such as n-heptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine , tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, tri-n-dodecylamine; diethanolamine, triethanolamine, diisopropanolamine, tri- Examples include alkyl alcohol amines such as isopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, trialkylamines having 5 to 10 carbon atoms are more preferred, and tri-n-pentylamine or tri-n-octylamine is particularly preferred.

Examples of the cyclic amine include heterocyclic compounds containing a nitrogen atom as a heteroatom. The heterocyclic compound may be monocyclic (aliphatic monocyclic amine) or polycyclic (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
The aliphatic polycyclic amine preferably has 6 to 10 carbon atoms, and specifically, 1,5-diazabicyclo[4.3.0]-5-nonene, 1,8-diazabicyclo[5. 4.0]-7-undecene, hexamethylenetetramine, 1,4-diazabicyclo[2.2.2]octane, and the like.

Other aliphatic amines include tris(2-methoxymethoxyethyl)amine, tris{2-(2-methoxyethoxy)ethyl}amine, tris{2-(2-methoxyethoxymethoxy)ethyl}amine, tris{2 -(1-methoxyethoxy)ethyl}amine, tris{2-(1-ethoxyethoxy)ethyl}amine, tris{2-(1-ethoxypropoxy)ethyl}amine, tris[2-{2-(2-hydroxy) Examples include ethoxy)ethoxy}ethyl]amine, triethanolamine triacetate, and triethanolamine triacetate is preferred.

Further, as the component (D2), an aromatic amine may be used.
Examples of aromatic amines include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine, and the like.

Component (D2) may be used alone or in combination of two or more.
When the resist composition contains component (D2), the content of component (D2) in the resist composition is usually in the range of 0.01 to 5 parts by mass based on 100 parts by mass of component (A). used. By setting it as the said range, a resist pattern shape, aging stability, etc. will improve.

<<At least one compound (E) selected from the group consisting of organic carboxylic acids, phosphorus oxoacids and derivatives thereof>>
The resist composition in this embodiment contains organic carboxylic acids, phosphorus oxoacids and derivatives thereof as optional components for the purpose of preventing sensitivity deterioration, improving resist pattern shape, storage stability over time, etc. At least one compound (E) selected from the group consisting of (hereinafter referred to as "component (E)") can be contained.
Suitable organic carboxylic acids include, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, and salicylic acid.
Examples of the phosphorus oxoacid include phosphoric acid, phosphonic acid, and phosphinic acid, and among these, phosphonic acid is particularly preferred.
Examples of derivatives of phosphorus oxo acids include esters in which the hydrogen atoms of the above oxo acids are replaced with hydrocarbon groups, and the hydrocarbon groups include alkyl groups having 1 to 5 carbon atoms, and esters having 6 to 5 carbon atoms. 15 aryl groups and the like.
Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphoric acid ester and diphenyl phosphoric acid ester.
Examples of phosphonic acid derivatives include phosphonic acid esters such as phosphonic acid dimethyl ester, phosphonic acid di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, and phosphonic acid dibenzyl ester.
Examples of derivatives of phosphinic acid include phosphinic esters and phenylphosphinic acid.
In the resist composition according to the present embodiment, one kind of component (E) may be used alone, or two or more kinds may be used in combination.
When the resist composition contains component (E), the content of component (E) is usually used in the range of 0.01 to 5 parts by mass based on 100 parts by mass of component (A).

≪Fluorine additive component (F)≫
The resist composition in this embodiment may contain a fluorine additive component (hereinafter referred to as "component (F)") in order to impart water repellency to the resist film or improve lithography properties.
The component (F) is described, for example, in JP-A No. 2010-002870, JP-A No. 2010-032994, JP-A No. 2010-277043, JP-A No. 2011-13569, and JP-A No. 2011-128226. The following fluorine-containing polymer compounds can be used.
More specifically, component (F) includes a polymer having a structural unit (f1) represented by the following general formula (f1-1). This polymer includes a polymer (homopolymer) consisting only of the structural unit (f1) represented by the following formula (f1-1); a copolymer of the structural unit (f1) and the above structural unit (a1); Preferably, it is a copolymer of the structural unit (f1), a structural unit derived from acrylic acid or methacrylic acid, and the structural unit (a1). Here, the structural unit (a1) copolymerized with the structural unit (f1) is a structural unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate, 1-methyl-1-adamantyl ( Preference is given to building blocks derived from meth)acrylates.

［式中、Ｒは前記と同様であり、Ｒｆ^１０２およびＲｆ^１０３はそれぞれ独立して水素原子、ハロゲン原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基を表し、Ｒｆ^１０２およびＲｆ^１０３は同じであっても異なっていてもよい。ｎｆ^１は０～５の整数であり、Ｒｆ^１０１はフッ素原子を含む有機基である。］

[wherein R is the same as above, Rf ¹⁰² and Rf ¹⁰³ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, Rf ¹⁰² and Rf ¹⁰³ may be the same or different. nf ¹ is an integer from 0 to 5, and Rf ¹⁰¹ is an organic group containing a fluorine atom. ]

In formula (f1-1), R bonded to the carbon atom at the α position is the same as described above. As R, a hydrogen atom or a methyl group is preferable.
In formula (f1-1), the halogen atoms of Rf ¹⁰² and Rf ¹⁰³ are particularly preferably fluorine atoms. Examples of the alkyl group having 1 to 5 carbon atoms for Rf ¹⁰² and Rf ¹⁰³ include those similar to the alkyl group having 1 to 5 carbon atoms for R above, and a methyl group or an ethyl group is preferable. Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms in Rf ¹⁰² and Rf ¹⁰³ include groups in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. It will be done. As the halogen atom, a fluorine atom is particularly preferred. Among these, Rf ¹⁰² and Rf ¹⁰³ are preferably a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms, and preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group.
In formula (f1-1), nf ¹ is an integer of 0 to 5, preferably an integer of 0 to 3, and more preferably 1 or 2.

In formula (f1-1), Rf ¹⁰¹ is an organic group containing a fluorine atom, and preferably a hydrocarbon group containing a fluorine atom.
The hydrocarbon group containing a fluorine atom may be linear, branched or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms. , carbon atoms of 1 to 10 are particularly preferred.
Further, in the hydrocarbon group containing a fluorine atom, it is preferable that 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more are fluorinated, and 60% or more are fluorinated. It is particularly preferable that the resist be fluorinated because it increases the hydrophobicity of the resist film during immersion exposure.
Among them, Rf ¹⁰¹ is preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms, such as trifluoromethyl group, -CH ₂ -CF ₃ , -CH ₂ -CF ₂ -CF ₃ , -CH(CF ₃ ) ₂ , -CH ₂ -CH ₂ -CF ₃ and -CH ₂ -CH ₂ -CF ₂ -CF ₂ -CF ₂ -CF ₃ are particularly preferred.

The weight average molecular weight (Mw) of the component (F) (based on polystyrene standards determined by gel permeation chromatography) is preferably from 1,000 to 50,000, more preferably from 5,000 to 40,000, and most preferably from 10,000 to 30,000. When it is below the upper limit of this range, there is sufficient solubility in a resist solvent for use as a resist, and when it is above the lower limit of this range, the water repellency of the resist film is good.
The degree of dispersion (Mw/Mn) of component (F) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5.

In the resist composition of the present embodiment, the component (F) may be used alone or in combination of two or more.
When the resist composition contains component (F), the content of component (F) is usually 0.5 to 10 parts by mass based on 100 parts by mass of component (A).

The resist composition in this embodiment may further include miscible additives, such as additional resins, dissolution inhibitors, plasticizers, stabilizers, colorants, antihalation agents to improve the performance of the resist film, if desired. , dyes, etc. may be added and contained as appropriate.

In the resist composition of this embodiment, impurities and the like may be removed using a polyimide porous membrane, a polyamide-imide porous membrane, etc. after the resist material is dissolved in the (S) component. For example, the resist composition may be filtered using a filter made of a porous polyimide membrane, a filter made of a porous polyamide-imide membrane, a filter made of a porous polyimide membrane and a porous polyamide-imide membrane, or the like. Examples of the polyimide porous membrane and the polyamideimide porous membrane include those described in JP-A No. 2016-155121.

<Process (via)>
Step (via) is a step of forming a resist film on the support using the above-mentioned resist composition.
In the above step, a specific resist composition described below is applied onto the support using a spinner or the like, and a baking (post-apply bake (PAB)) treatment is performed at, for example, 80 to 150°C, preferably 100 to 150°C ( A method of forming a resist film by applying the resist film at a temperature of 40 to 120 seconds, preferably 60 to 120 seconds under a temperature condition of more preferably 100° C. to 150° C. or less.

The support is not particularly limited, and conventionally known supports can be used, such as substrates for electronic components, substrates on which predetermined wiring patterns are formed, and the like. More specifically, examples include silicon wafers, metal substrates such as copper, chromium, iron, and aluminum, and glass substrates. As the material for the wiring pattern, for example, copper, aluminum, nickel, gold, etc. can be used.
Further, the support may be one in which an inorganic and/or organic film is provided on the substrate as described above. Examples of the inorganic film include an inorganic antireflection film (inorganic BARC). Examples of the organic film include organic films such as an organic antireflection film (organic BARC) and a lower organic film in a multilayer resist method.
Here, the multilayer resist method means that at least one layer of organic film (lower layer organic film) and at least one layer of resist film (upper layer resist film) are provided on a substrate, and the resist pattern formed on the upper layer resist film is used as a mask. This is a method of patterning a lower organic film, and is said to be able to form patterns with high aspect ratios. That is, according to the multilayer resist method, since the required thickness can be ensured by the lower organic film, the resist film can be made thinner, and a fine pattern with a high aspect ratio can be formed.
Multilayer resist methods basically include a two-layer structure consisting of an upper resist film and a lower organic film (two-layer resist method) and one or more intermediate layers between the upper resist film and the lower organic film. There are two methods: a method of creating a multilayer structure of three or more layers (three-layer resist method), and a method of forming a multilayer structure of three or more layers (metal thin film, etc.).

<Process (viia)>
Step (viia) is a step of exposing the resist film, and a step of developing the exposed resist film to form a resist pattern.
In the above step, the resist film is selectively exposed to light through a mask (mask pattern) on which a predetermined pattern is formed using, for example, an exposure device.

The wavelength used for exposure is not particularly limited, and may include ArF excimer laser, KrF excimer laser, _F2 excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. It can be done using radiation.

The method of exposing the resist film may be normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or liquid immersion lithography.
In immersion exposure, the space between the resist film and the lowest lens of the exposure device is filled in advance with a solvent (immersion medium) that has a refractive index greater than that of air, and exposure (immersion exposure) is performed in that state. This is an exposure method.
The immersion medium is preferably a solvent having a refractive index greater than that of air and smaller than the refractive index of the resist film to be exposed. The refractive index of such a solvent is not particularly limited as long as it falls within the above range.
Examples of the solvent having a refractive index higher than that of air and lower than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicon-based solvent, a hydrocarbon-based solvent, and the like.
Specific examples of fluorine-based inert liquids include those whose main component is a fluorine-based compound such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , and C ₅ H ₃ F ₇ Examples include liquids, and those with a boiling point of 70 to 180°C are preferable, and those with a boiling point of 80 to 160°C are more preferable. It is preferable that the fluorine-based inert liquid has a boiling point within the above range because the medium used for immersion can be removed by a simple method after exposure is completed.
As the fluorine-based inert liquid, a perfluoroalkyl compound in which all hydrogen atoms of an alkyl group are substituted with fluorine atoms is particularly preferable. Specific examples of the perfluoroalkyl compound include perfluoroalkyl ether compounds and perfluoroalkylamine compounds.
Further, specifically, the perfluoroalkyl ether compound may include perfluoro(2-butyl-tetrahydrofuran) (boiling point 102°C), and the perfluoroalkylamine compound may include perfluorotributylamine ( (boiling point 174°C).
Water is preferably used as the immersion medium from the viewpoints of cost, safety, environmental issues, versatility, and the like.

Thereafter, a bake (post-exposure bake (PEB)) treatment is performed, for example, at a temperature of 80 to 150°C, preferably 90 to 130°C, for 40 to 120 seconds, preferably 60 to 100 seconds.
Next, the exposed resist film is developed with an alkaline developer containing a nonionic surfactant to form a resist pattern.

As the developer, an alkaline developer containing a nonionic surfactant is used. For example, the developer includes a 0.1 to 10% by mass aqueous solution of tetramethylammonium hydroxide (TMAH) containing a nonionic surfactant.
Further, as the nonionic surfactant contained in the alkaline developer, a known nonionic surfactant can be blended. Specifically, for example, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether; polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether polyoxyethylene alkyl allyl ethers such as; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate; and polyoxyethylene sorbitan Polyoxyethylene sorbitan fatty acid esters such as monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; acetylene glycol, acetylene glycol Examples include acetylenes such as oxyethylene adducts.

The blending amount of the nonionic surfactant is usually preferably 0.001 to 5% by mass, more preferably 0.005 to 2% by mass, and further preferably 0.01 to 0.5% by mass, based on the total amount of the developer. preferable.

The development process can be carried out by a known development method, such as a method in which the support is immersed in a developer for a certain period of time (dipping method), a method in which the support is heaped up on the surface of the support by surface tension, and then left for a certain period of time. (paddle method), spraying the developer onto the surface of the support (spray method), and applying the developer onto the rotating support while scanning the developer application nozzle at a constant speed. Examples include a continuous dispensing method (dynamic dispensing method), etc.

After the development process, preferably a rinsing process is performed. The rinsing treatment is preferably water rinsing using pure water.
After development processing or rinsing processing, drying is performed. In some cases, a bake process (post-bake) may be performed after the development process.
A resist pattern can also be formed in this way.

The rinsing process (cleaning process) using a rinsing liquid can be performed by a known rinsing method. Examples of the rinsing method include a method of continuously applying a rinsing liquid onto a support rotating at a constant speed (rotary coating method), a method of immersing the support in a rinsing liquid for a certain period of time (dipping method), Examples include a method of spraying a rinsing liquid onto the surface of the support (spray method).

(Second aspect)
A second aspect of the present invention is (ib) copolymerizing a compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) by living radical polymerization. to obtain an alternating copolymer represented by the following general formula (p0) (hereinafter also referred to as step (ib)); and (iib) hydrolyzing the alternating copolymer to obtain an alternating copolymer represented by the following general formula (Pre). -2a) (hereinafter also referred to as step (iib)), (iiib) the first polymer compound precursor and the following general formula (Add- 1) to obtain a polymer compound (A01) represented by the following general formula (p1) (hereinafter also referred to as step (iiib)); A step of preparing a resist composition by mixing the molecular compound (A01) and an organic solvent (hereinafter also referred to as step (ivb)), and (vb) forming a resist film on a support using the resist composition. (hereinafter also referred to as step (vb)), (vib) a step of exposing the resist film, and a step of developing the exposed resist film to form a resist pattern (hereinafter referred to as step (vib)). )).

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０２及びＲｐ^０３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒｐ^０２及びＲｐ^０３は、相互に結合して環を形成していてもよい。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。ｎ_１は０～４の整数である。Ｒａ^００１、Ｒａ^００２及びＲａ^００３は、それぞれ独立に置換基を有してもよい炭化水素基である。Ｒａ^００２及びＲａ^００３は、相互に結合して環を形成していてもよい。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. ]

<Step (ib)>
Step (ib) is the same as step (ia) described above.

<Process (iib)>
Step (ib) is a step of hydrolyzing the alternating copolymer represented by the above general formula (p0) to obtain a first polymer compound precursor represented by the above general formula (Pre-2a). be.

The alternating copolymer can be hydrolyzed by adding the alternating copolymer and an acid component to a solvent and mixing them. Examples of the solvent include those similar to those used in the atom transfer radical polymerization described above.

≪Acid component≫
The acid component is not particularly limited, and may be an inorganic acid or an organic acid.
Examples of such acid components include organic acids such as acetic acid, oxalic acid, p-toluenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, and malonic acid; inorganic acids such as sulfuric acid, hydrochloric acid, phosphoric acid, and hydrobromic acid. can be mentioned.
In the manufacturing method of this embodiment, one type of acid component may be used alone, or two or more types may be used in combination.

The temperature conditions during the reaction between the alternating copolymer and the acid component are not particularly limited, and are, for example, about 0 to 120°C.
The reaction time between the alternating copolymer and the acid component is not particularly limited, and is, for example, about 1 to 72 hours.

<Process (iiib)>
In step (iiib), the first polymer compound precursor represented by the above general formula (Pre-2a) and the compound represented by the above general formula (Add-1) are reacted to form the above general formula This is a step of obtaining a polymer compound represented by (p1).

As a method for reacting the first polymer compound precursor with the compound represented by the general formula (Add-1), the first polymer compound precursor, the compound represented by the general formula (Add-1), ) and the above-mentioned acid component as a catalyst are added to a solvent and mixed. Examples of the solvent include those similar to those used in the atom transfer radical polymerization described above.

The temperature conditions for reacting the first polymer compound precursor with the compound represented by the general formula (Add-1) are not particularly limited, and are, for example, about 0 to 120°C.
The reaction time for reacting the first polymer compound precursor with the compound represented by the general formula (Add-1) is not particularly limited, and is, for example, about 1 to 72 hours.

The temperature conditions during the reaction between the alternating copolymer and the acid component are not particularly limited, and are, for example, about 0 to 120°C.
The reaction time between the alternating copolymer and the acid component is not particularly limited, and is, for example, about 1 to 72 hours.

The compound represented by the above general formula (Add-1) and the polymer compound represented by the above general formula (p1) are the same as described in the first embodiment.

The above steps (ivb) to (vib) are the same as the above steps (va) to (viia).

(Third aspect)
A third aspect of the present invention is that (ic) the compound represented by the above general formula (m0-1) and the compound represented by the above general formula (m0-2) are copolymerized by living radical polymerization. and (iic) hydrolyzing the alternating copolymer to obtain the alternating copolymer represented by the general formula (P0) (hereinafter also referred to as step (ic)). -1a) (hereinafter also referred to as step (iic)), (iiiic) the first polymer compound precursor and the above general formula (Add- 2) and a step of obtaining a second polymer compound precursor represented by the above general formula (Pre-1b-2) (hereinafter also referred to as step (iiic)); , (ivc) a step of hydrolyzing the second polymer compound precursor to obtain the polymer compound (A02) represented by the general formula (p2) (hereinafter also referred to as step (ivc)); (vc) a step of preparing a resist composition by mixing the polymer compound (A02) and an organic solvent (hereinafter also referred to as step (vc)); and (vic) preparing the resist composition on a support. (hereinafter also referred to as step (vic)); (viic) exposing the resist film to light; and developing the exposed resist film to form a resist pattern (viic). Hereinafter, the resist pattern forming method includes steps (hereinafter also referred to as step (VIIC)).

The above step (ic) is the same as the above step (ia), and the above step (iic) is the same as the above step (IIA).

<Process (iiic)>
In step (iiic), a first polymer compound precursor represented by the following general formula (Pre-1a) and a compound represented by the following general formula (Add-2) are reacted to form the following general formula. This is a step of obtaining a second polymer compound precursor represented by formula (Pre-1b-2).

［式中、Ｒｐ^０１は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖｐ^０１は、単結合又は２価の連結基である。Ｒｐ^０４は、水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｒｐ^０５は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、シアノ基又は水酸基である。Ｒｐ^０６は、直鎖状又は分岐鎖状の脂肪族炭化水素基である。ｎ_１は０～４の整数である。Ｒａ^００４、Ｒａ^００５は水素原子又はアルキル基である。Ｒａ^００６は炭化水素基であって、Ｒａ^００６は、Ｒａ^００４、Ｒａ^００５のいずれかと結合して環を形成してもよい。Ｘは、ハロゲン原子である。］

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. Ra ⁰⁰⁴ and Ra ⁰⁰⁵ are hydrogen atoms or alkyl groups. Ra ⁰⁰⁶ is a hydrocarbon group, and Ra ⁰⁰⁶ may be combined with either Ra ⁰⁰⁴ or Ra ⁰⁰⁵ to form a ring. X is a halogen atom. ]

The first polymer compound precursor represented by the general formula (Pre-1a) is the same as that described in step (iia) above.

In the above general formula (Add-2), Ra ⁰⁰⁴ and Ra ⁰⁰⁵ are hydrogen atoms or alkyl groups.
At least one of Ra ⁰⁰⁴ and Ra ⁰⁰⁵ is preferably a hydrogen atom, and more preferably both are hydrogen atoms.

When Ra ⁰⁰⁴ or Ra ⁰⁰⁵ is an alkyl group, the alkyl group is preferably an alkyl group having 1 to 5 carbon atoms. Specifically, linear or branched alkyl groups are preferably mentioned. More specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. More preferred is a methyl group, even more preferred.

In the above general formula (Add-2), the hydrocarbon group represented by Ra ⁰⁰⁶ includes a linear or branched alkyl group, or a cyclic hydrocarbon group.
The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include methyl group, ethyl group, n-propyl group, n-butyl group, and n-pentyl group. Among these, methyl group, ethyl group or n-butyl group are preferred, and methyl group or ethyl group is more preferred.

The branched alkyl group preferably has 3 to 10 carbon atoms, more preferably 3 to 5 carbon atoms. Specific examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, and isopropyl group is preferred.

When Ra ⁰⁰⁶ is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group.
As the aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane.
The aliphatic hydrocarbon group which is a polycyclic group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically Examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

When the cyclic hydrocarbon group of Ra ⁰⁰⁶ is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, even more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms.
Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; Can be mentioned. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, the aromatic hydrocarbon group in Ra ⁰⁰⁶ includes a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); containing two or more aromatic rings. A group obtained by removing one hydrogen atom from an aromatic compound (e.g. biphenyl, fluorene, etc.); a group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocycle is substituted with an alkylene group (e.g. benzyl group, arylalkyl groups such as phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group). The alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon number. preferable.

The cyclic hydrocarbon group in Ra ⁰⁰⁶ may have a substituent. Examples of this substituent include -R ^P1 , -R ^P2 -O-R ^P1 , -R ^P2 -CO-R P1 , -R ^P2 -CO-OR ^P1 , -R ^P2 -O-CO-R ^{P1 ,} -R ^P2 -OH, -R ^P2 -CN or -R ^P2 -COOH (hereinafter these substituents are also collectively referred to as "Ra ⁰⁵ "), and the like.
Here, R ^P1 is a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic group having 6 to 30 carbon atoms. It is a group hydrocarbon group. R ^P2 is a single bond, a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent saturated hydrocarbon group having 6 to 30 carbon atoms. is an aromatic hydrocarbon group. However, some or all of the hydrogen atoms of the chain saturated hydrocarbon group, aliphatic cyclic saturated hydrocarbon group, and aromatic hydrocarbon group of R ^P1 and R ^P2 may be substituted with fluorine atoms. The aliphatic cyclic hydrocarbon group may have one or more of the above substituents, or may have one or more of each of the above substituents.
Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, etc. .
Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, cyclododecyl group, etc. Monocyclic aliphatic saturated hydrocarbon group; bicyclo[2.2.2]octanyl group, tricyclo[5.2.1.02,6]decanyl group, tricyclo[3.3.1.13,7]decanyl group , tetracyclo[6.2.1.13,6.02,7]dodecanyl group, adamantyl group, and other polycyclic aliphatic saturated hydrocarbon groups.
Examples of monovalent aromatic hydrocarbon groups having 6 to 30 carbon atoms include groups obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene.

When Ra ⁰⁰⁶ is combined with either Ra' ¹ or Ra' ² to form a ring, the cyclic group is preferably a 4- to 7-membered ring, more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group, a tetrahydrofuranyl group, and the like.

In the above general formula (Add-2), examples of the halogen atom in X include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. Among them, a chlorine atom is preferred for ease of handling. .

As a method for reacting the first polymer compound precursor with the compound represented by the general formula (Add-2), a method known as esterification can be used. For example, this can be carried out by adding and mixing the first polymer compound precursor, the compound represented by the general formula (Add-2), and a base component (DBU (registered trademark), etc.) in a solvent. .
Examples of the solvent include those similar to those used in the atom transfer radical polymerization described above.

The temperature conditions for reacting the first polymer compound precursor with the compound represented by the general formula (Add-2) are not particularly limited, and are, for example, about 0 to 120°C.
The reaction time for reacting the first polymer compound precursor with the compound represented by the general formula (Add-2) is not particularly limited, and is, for example, about 1 to 72 hours.

Rp ⁰¹ , Vp ⁰¹ , Rp ⁰⁴ , Rp ⁰⁵ , Rp ⁰⁶ , and n ₁ in the above formula (Pre-1b-2) are the same as those explained in the above formula (m0-1) and the above formula (m0-2). The same is true.

Ra ⁰⁰⁴ , Ra ⁰⁰⁵ , and Ra ⁰⁰⁶ in the above formula (Pre-1b-2) are the same as Ra ⁰⁰⁴ , Ra ⁰⁰⁵ , and Ra ⁰⁰⁶ in the above formula (Add-2), respectively.
In the above formula (Pre-1b-2), -C(Ra ⁰⁰⁴ )(Ra ⁰⁰⁵ )-O-(Ra ⁰⁰⁶ ) is an acid dissociable group (acetal type acid dissociable group). By the action of the acid, -C(Ra ⁰⁰⁴ )(Ra ⁰⁰⁵ )-O-(Ra ⁰⁰⁶ ) is dissociated, a highly polar group (carboxy group) is generated, and the polarity is increased.

<Process (ivc)>
The above step (ivc) is a step of hydrolyzing the second polymer compound precursor represented by the above formula (Pre-1b-2) to obtain a polymer compound represented by the above general formula (p2). It is.

The second polymer compound precursor can be hydrolyzed by adding and mixing the second polymer compound precursor and a base component to a solvent. Examples of the solvent include those similar to those used in the atom transfer radical polymerization described above.
The base component, the amount of the base component used, the reaction time, etc. are the same as those explained in <Step (iva)> above.

Rp ⁰¹ , Vp ⁰¹ , Rp ⁰⁴ , Rp ⁰⁵ , and n ₁ in the above general formula (p2) are the same as explained in the above formula (m0-1) and the above formula (m0-2).
Ra ⁰⁰⁴ , Ra ⁰⁰⁵ , and Ra ⁰⁰⁶ in the above general formula (p2) are the same as Ra ⁰⁰⁴ , Ra ⁰⁰⁵ , and Ra ⁰⁰⁶ in the above formula (Add-2), respectively.

Steps (vc) to (viic) are the same as described in steps (va) to (viia) above, except that component (A) of the resist composition contains a polymer compound (A02).

(Fourth aspect)
A fourth aspect of the present invention is that (id) the compound represented by the above general formula (m0-1) and the compound represented by the above general formula (m0-2) are copolymerized by living radical polymerization. and (iid) hydrolyzing the alternating copolymer to obtain the alternating copolymer represented by the general formula (P0) (hereinafter also referred to as step (id)). -2a) (hereinafter also referred to as step (iid)), (iiid) the first polymer compound precursor and the above general formula (Add- 2) to obtain the polymer compound (A02) represented by the general formula (p2) (hereinafter also referred to as step (iiid)); A step of preparing a resist composition by mixing the molecular compound (A02) and an organic solvent (hereinafter also referred to as step (ivd)), and (vd) forming a resist film on a support using the resist composition. (hereinafter also referred to as step (vd)), (vid) a step of exposing the resist film, and a step of developing the exposed resist film to form a resist pattern (hereinafter referred to as step (vid)). )).

The above step (id) is the same as the above step (ib), and the above step (iid) is the same as the above step (iib).

<Process (iiid)>
In step (iiid), the first polymer compound precursor represented by the above general formula (Pre-2a) and the compound represented by the above general formula (Add-2) are reacted to form the above general formula (Add-2). This is a step of obtaining a polymer compound represented by formula (p2).

Examples of the method for reacting the first polymer compound precursor with the compound represented by the general formula (Add-2) include the above-mentioned known esterification reaction.

The temperature conditions for reacting the first polymer compound precursor with the compound represented by the general formula (Add-2) are not particularly limited, and are, for example, about 0 to 120°C.
The reaction time for reacting the first polymer compound precursor with the compound represented by the general formula (Add-2) is not particularly limited, and is, for example, about 1 to 72 hours.

The compound represented by the above general formula (Add-2) and the polymer compound represented by the above general formula (p2) are the same as described in the third embodiment.

Steps (ivd) to (vid) are the same as described in steps (via) to (viiia) above, except that component (A) of the resist composition contains a polymer compound (A02).

The resist pattern forming method of the present embodiment described above uses a compound (monomer) (m0-1) whose hydroxystyrene skeleton is protected with a group that can be deprotected with an acid component, and a compound (monomer) having a specific imide structure. By copolymerizing with (m0-2), the polymerization is controlled by electronic and chemical properties, so variations in each constituent unit of the resulting alternating copolymer are suppressed. Therefore, it is presumed that the lithography characteristics can be improved by forming a resist pattern using a resist composition containing a polymer compound obtained from the alternating copolymer.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.

<Production example 1 of alternating copolymer>
In a 50 mL reactor, 6.4 mg (0.0080 mol) of RuCp ^* catalyst and 0.615 mL (4.0 mmol) of p-acetoxystyrene (PACS) were dissolved in 1.0 mL of cyclohexanone. Furthermore, in the 50 mL reactor, 0.02 mL (0.080 mmol) of tributylamine, 0.988 g (4.0 mmol) of the monomer (M0-1-1), and 0.014 mL (0.014 mL) of ethyl 2-chloro-2-phenylacetate ( 0.080 mmol) was added thereto, and a polymerization reaction was carried out at 80° C. for 24 hours. After the polymerization reaction was completed, the reaction solution was rapidly cooled to -78°C in a methanol-dry ice ice bath to obtain an alternating copolymer (p0-1) (0.564 g).

Regarding the obtained alternating copolymer (p0-1), the weight average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement was 13,700, and the molecular weight dispersity (Mw/Mn) was 1.25.
In addition, the copolymerization composition ratio (ratio of ^each structural unit in the structural formula (molar ^ratio )) was l/m=50/50.

The alternating copolymer (p0-1) was evaluated for alternating polymerizability using MALDI-TOF-MS. As a result, the peaks of each structural unit were confirmed alternately, and it was confirmed that there was little variation in each structural unit in the alternating copolymer.

<Production example 1 of polymer compound>
The above alternating copolymer (p0-1) (0.15 mol (30.71 g)) and hydrazine monohydrate (0.19 mol) were dissolved in THF (200 mL) and stirred at 65° C. for 4 hours.
After the reaction solution was allowed to cool to room temperature, it was further cooled to 0° C., hydrochloric acid (100 mL) was added dropwise, and the resulting powder was collected. The powder was dried under reduced pressure to obtain a first polymer compound precursor (Pre-1a-1) (0.13 mol (16.14 g)).

In a 500 mL three-necked flask, dissolve the first polymer compound precursor (Pre-1a-1) (0.13 mol (16.14 g)) in three times the amount of dichloromethane, replace with nitrogen, and cool to below 5°C. I did it. A dichloromethane solution of 4-dimethylaminopyridine (DMAP) (0.03 mol) was added dropwise thereto over 5 minutes at a temperature not exceeding 10°C. Furthermore, tert-butyl alcohol (0.45 mol) was added dropwise over 15 minutes, and the mixture was aged for 10 minutes.
Thereafter, a dichloromethane solution of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC/HCl) (0.38 mol) was added dropwise at a temperature below 10°C over 90 minutes, and the mixture was kept at a temperature below 10°C for 18 hours. Stirring was performed.
Thereafter, the organic layer was collected by washing with 1% hydrochloric acid. Then, washing with water was repeated three times.
Thereafter, the organic layer was concentrated, and tert-butyl methyl ether (TBME) was added dropwise to the concentrated liquid over 1 hour.
The solid content was collected and dried under reduced pressure to obtain a second polymer compound precursor (Pre-1b-11) (0.10 mol (16.52 g)).

The second polymer compound precursor (Pre-1b-11) (0.1 mol (16.52 g)) was dissolved in methyl ethyl ketone (MEK) and dissolved at room temperature using an equimolar 1% K ₂ CO ₃ aqueous solution. Stirring was performed for 1 hour.
Thereafter, it was dropped into a mixed solvent of heptane/isopropyl alcohol over 30 minutes to precipitate and obtain a powder.
The obtained powder was dispersed and washed multiple times using a mixed solvent of heptane/isopropyl alcohol.
The solid content was collected and dried under reduced pressure to obtain a polymer compound (p1-1-1) (0.06 mol (7.8 g)).

The weight average molecular weight (Mw) of the obtained polymer compound (p1-1-1) in terms of standard polystyrene determined by GPC measurement was 9,000.
In addition, the copolymerization composition ratio (ratio of each structural unit in the structural formula ( ^{molar ratio} )) was l/m=50/50.

<Production example 2 of polymer compound>
The above alternating copolymer (p0-1) (0.15 mol (29.50 g)) was dissolved in methyl ethyl ketone (MEK) (100 mL), and stirred at room temperature for 1 hour using methanesulfonic acid (50 mL).
Thereafter, it was dropped into a mixed solvent of heptane/isopropyl alcohol over 30 minutes to precipitate and obtain a powder. The obtained powder was dispersed and washed multiple times using a mixed solvent of heptane/isopropyl alcohol.
The solid content was collected and dried under reduced pressure to obtain a polymer compound precursor (Pre-2a-1) (0.11 mol (21.63 g)).

A polymer compound precursor (Pre-2a-1) was dissolved in a mixed solvent of dimethylformamide (DMF)/tert-butyl alcohol in a 500 mL three-necked flask, concentrated sulfuric acid was added, and the mixture was heated under reflux for 12 hours.
After the reaction was completed, the temperature was returned to room temperature, water was added to precipitate a solid, and dispersion washing was repeated three times with water to return the pH to neutral.
The solid content was collected and dried under reduced pressure to obtain a polymer compound (p1-2-1) (0.02 mol (2.62 g)).

The weight average molecular weight (Mw) of the obtained polymer compound (p1-2-1) determined by GPC measurement was 9,000 in terms of standard polystyrene.
In addition, the copolymerization composition ratio (ratio of ^each structural unit in the structural formula (molar ^ratio )) was l/m=50/50.

The following polymer compounds (p1-1-2) to (p1-1-8) were manufactured in the same manner as in Production Example 1 of the polymer compound.
Regarding the obtained polymer compound, the copolymerization composition ratio (ratio (mole ratio) of each structural unit in the polymer compound) of the polymer compound determined by ¹³ C-NMR, and the standard polystyrene equivalent determined by GPC measurement. The weight average molecular weight (Mw) and molecular weight dispersity (Mw/Mn) are also listed in Table 1.

<Production example 2 of polymer compound>
An alternating copolymer (p0-1) was obtained by the same method as in the above production example of an alternating copolymer. The alternating copolymer (p0-1) (0.15 mol (29.50 g)) was dissolved in methyl ethyl ketone (MEK) (100 mL), and stirred at room temperature for 1 hour using methanesulfonic acid (50 mL).
Thereafter, it was dropped into a mixed solvent of heptane/isopropyl alcohol over 30 minutes to precipitate and obtain a powder. The obtained powder was dispersed and washed multiple times using a mixed solvent of heptane/isopropyl alcohol.
The solid content was collected and dried under reduced pressure to obtain a polymer compound precursor (Pre-2a-1) (0.11 mol (21.63 g)).

In a 500 mL three-neck flask, dissolve the precursor of the first polymer compound (Pre-2a-1) in DBU (registered trademark) (0.08 mol) and 100 ml of DMF, add compound 1 (0.15 mol), and heat for 4 hours. Reflux was performed. After cooling, water was added to obtain a solid content, and dispersion washing was further performed twice with water.
The solid content was collected and dried under reduced pressure to obtain a polymer compound (p2-1-1) (0.02 mol: 3.70 g).

The obtained polymer compound (p2-1-1) had a weight average molecular weight (Mw) of 12,300 and a molecular weight dispersity (Mw/Mn) of 1.32 in terms of standard polystyrene determined by GPC measurement.
In addition, the copolymerization composition ratio (ratio of each structural unit in the structural formula ( ^{molar ratio} )) was l/m=50/50.

<Production example 3 of polymer compound>
10.0 g of monomer (a10-1pre), 9.5 g of monomer (a1-1-1), 1.4 g of dimethyl azobis(isobutyrate) (V-601) as a polymerization initiator, and 50.0 g of MEK (methyl ethyl ketone). The solution was heated to 85° C. under nitrogen atmosphere and stirred for 5 hours. Thereafter, 9.4 g of acetic acid and 160 g of methanol were added to the reaction solution, and a deprotection reaction was carried out at 30° C. for 8 hours. After the reaction was completed, the resulting reaction solution was precipitated in 2500 g of heptane and washed. The obtained white solid was filtered and dried under reduced pressure overnight to obtain 10.1 g of the target polymer compound (A-10).

The following polymer compounds (A-11) to (A-19) were produced in the same manner as the polymer compound (A-10).
Regarding the obtained polymer compound, the copolymerization composition ratio (ratio (mole ratio) of each structural unit in the polymer compound) of the polymer compound determined by ¹³ C-NMR, and the standard polystyrene equivalent determined by GPC measurement. The weight average molecular weight (Mw) and molecular weight dispersity (Mw/Mn) are also listed in Table 2.

<Preparation of resist composition>
(Examples 1 to 9, Comparative Examples 1 to 9)
Each component shown in Tables 3 and 4 was mixed and dissolved to prepare a resist composition for each example.

In Tables 3 and 4, each abbreviation has the following meaning. The numbers in brackets are the amount (parts by mass).
(A)-1: The above polymer compound (p1-1-1).
(A)-2: The above polymer compound (p1-1-2).
(A)-3: The above polymer compound (p1-1-3).
(A)-4: The above polymer compound (p1-1-4).
(A)-5: The above polymer compound (p1-1-5).
(A)-6: The above polymer compound (p2-1-1).
(A)-7: The above polymer compound (p1-1-6).
(A)-8: The above polymer compound (p1-1-7).
(A)-9: The above polymer compound (p1-1-8).

(A)-10 to (A)-18: The above polymer compounds (A-10) to (A-18).
(B)-1: An acid generator consisting of a compound represented by the following chemical formula (B-1).

(S)-1: Mixed solvent of propylene glycol monomethyl ether acetate/propylene glycol monomethyl ether = 80/20 (mass ratio).

<Formation of resist pattern>
The resist composition of each example was applied using a spinner onto an 8-inch silicon substrate treated with hexamethyldisilazane (HMDS), and pre-baked (PAB) at a temperature of 110°C for 60 seconds on a hot plate. By processing and drying, a resist film with a thickness of 50 nm was formed.
Next, using an electron beam lithography system JEOL-JBX-9300FS (manufactured by JEOL Ltd.), the target size was set to the resist film in a 1:1 line and space pattern (hereinafter referred to as After drawing (exposure) to form a "LS pattern"), post-exposure heating (PEB) treatment was performed at 90° C. for 60 seconds.
Next, at 23°C, alkaline development was performed for 60 seconds using a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution "NMD-3" (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.). A water rinse was performed using pure water for 15 seconds. As a result, a 1:1 LS pattern with a line width of 50 nm was formed.

[Evaluation of optimal exposure amount (Eop)]
The optimum exposure amount Eop (μC/cm ² ) for forming an LS pattern of the target size in the above <Formation of resist pattern> was determined. This is shown in Tables 5 and 6 as "Eop (μC/cm ² )".

[Evaluation of LWR (line width roughness)]
For the LS pattern formed in the above <Formation of resist pattern>, 3σ, which is a measure indicating LWR, was determined. This is shown in Tables 5 and 6 as "LWR (nm)".
"3σ" is the standard deviation determined from the measurement results obtained by measuring line positions at 400 locations in the longitudinal direction of the line using a scanning electron microscope (acceleration voltage 800V, product name: S-9380, manufactured by Hitachi High-Technologies). (σ) triple value (3σ) (unit: nm).
The smaller the value of 3σ, the smaller the roughness of the line sidewalls, meaning that an LS pattern with a more uniform width was obtained.

From the results shown in Tables 5 and 6, it can be confirmed that the resist pattern forming method of the example is superior in reducing roughness compared to the resist pattern forming method of the comparative example.

Claims (4)

A compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) are copolymerized by living radical polymerization to form a compound represented by the following general formula (p0). obtaining an alternating copolymer;
Hydrolyzing the alternating copolymer to obtain a first polymer compound precursor represented by the following general formula (Pre-1a);
The first polymer compound precursor and a compound represented by the following general formula (Add-1) are reacted to form a second polymer represented by the following general formula (Pre-1b-1). Obtaining a compound precursor;
Hydrolyzing the second polymer compound precursor to obtain a polymer compound (A01) represented by the following general formula (p1);
a step of preparing a resist composition by mixing the polymer compound (A01) and an organic solvent;
forming a resist film on a support using the resist composition;
a step of exposing the resist film;
Developing the exposed resist film to form a resist pattern;
A method for forming a resist pattern.

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. ]

[In the formula, Rp ⁰¹ and Rp ⁰⁴ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. ] A compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) are copolymerized by living radical polymerization to form a compound represented by the following general formula (p0). obtaining an alternating copolymer;
Hydrolyzing the alternating copolymer to obtain a first polymer compound precursor represented by the following general formula (Pre-2a);
A step of reacting the first polymer compound precursor with a compound represented by the following general formula (Add-1) to obtain a polymer compound (A01) represented by the following general formula (p1). and,
a step of preparing a resist composition by mixing the polymer compound (A01) and an organic solvent;
forming a resist film on a support using the resist composition;
a step of exposing the resist film;
Developing the exposed resist film to form a resist pattern;
A method for forming a resist pattern.

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. Ra ⁰⁰¹ , Ra ⁰⁰² and Ra ⁰⁰³ are each independently a hydrocarbon group which may have a substituent. Ra ⁰⁰² and Ra ⁰⁰³ may be bonded to each other to form a ring. ] A compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) are copolymerized by living radical polymerization to form a compound represented by the following general formula (p0). obtaining an alternating copolymer;
Hydrolyzing the alternating copolymer to obtain a first polymer compound precursor represented by the following general formula (Pre-1a);
The first polymer compound precursor and a compound represented by the following general formula (Add-2) are reacted to form a second polymer represented by the following general formula (Pre-1b-2). Obtaining a compound precursor;
Hydrolyzing the second polymer compound precursor to obtain a polymer compound (A02) represented by the following general formula (p2);
a step of preparing a resist composition by mixing the polymer compound (A02) and an organic solvent;
forming a resist film on a support using the resist composition;
a step of exposing the resist film;
Developing the exposed resist film to form a resist pattern;
A method for forming a resist pattern.

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. Ra ⁰⁰⁴ and Ra ⁰⁰⁵ are hydrogen atoms or alkyl groups. Ra ⁰⁰⁶ is a hydrocarbon group, and Ra ⁰⁰⁶ may be combined with either Ra ⁰⁰⁴ or Ra ⁰⁰⁵ to form a ring. X is a halogen atom. ]

[In the formula, Rp ⁰¹ and Rp ⁰⁴ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Ra ⁰⁰⁴ and Ra ⁰⁰⁵ are hydrogen atoms or alkyl groups. Ra ⁰⁰⁶ is a hydrocarbon group, and Ra ⁰⁰⁶ may be combined with either Ra ⁰⁰⁴ or Ra ⁰⁰⁵ to form a ring. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. ] A compound represented by the following general formula (m0-1) and a compound represented by the following general formula (m0-2) are copolymerized by living radical polymerization to form a compound represented by the following general formula (p0). obtaining an alternating copolymer;
Hydrolyzing the alternating copolymer to obtain a first polymer compound precursor represented by the following general formula (Pre-2a);
A step of reacting the first polymer compound precursor with a compound represented by the following general formula (Add-2) to obtain a polymer compound (A02) represented by the following general formula (p2). and,
a step of preparing a resist composition by mixing the polymer compound (A02) and an organic solvent;
forming a resist film on a support using the resist composition;
a step of exposing the resist film;
Developing the exposed resist film to form a resist pattern;
A method for forming a resist pattern.

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰² and Rp ⁰³ are each independently a hydrocarbon group which may have a substituent. Rp ⁰² and Rp ⁰³ may be bonded to each other to form a ring. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. Rp ⁰⁶ is a linear or branched aliphatic hydrocarbon group. n ₁ is an integer from 0 to 4. ]

[In the formula, Rp ⁰¹ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Vp ⁰¹ is a single bond or a divalent linking group. Rp ⁰⁴ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rp ⁰⁵ is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a cyano group, or a hydroxyl group. n ₁ is an integer from 0 to 4. Ra ⁰⁰⁴ and Ra ⁰⁰⁵ are hydrogen atoms or alkyl groups. Ra ⁰⁰⁶ is a hydrocarbon group, and Ra ⁰⁰⁶ may be combined with either Ra ⁰⁰⁴ or Ra ⁰⁰⁵ to form a ring. X is a halogen atom. ]