WO2024062998A1 - Polymer, resist composition containing said polymer, method for manufacturing member using same, and pattern formation method - Google Patents

Abstract

Provided are: a polymer which mitigates sensitivity decrease caused by a decrease in energy application density in patterning performed by irradiation with strong particle beams or electromagnetic waves of particles and photon energy and which is used in a resist composition having excellent development contrast characteristics and etching resistance; a resist composition containing said polymer; a method for manufacturing a member using said resist composition; and a pattern formation method.　The polymer includes: a unit A which has an onium salt structure and generates acid by irradiation with particle beams or electromagnetic waves; and an organometallic compound-containing unit B having a metal atom selected from the group consisting of Sn, Sb, Ge, Bi, and Te, wherein the unit A is a polymer represented by formula (1). (In general formula (1), R¹ is one selected from the group consisting of a hydrogen atom, a linear, branched, or cyclic C1–C6 alkyl group, and a linear, branched, or cyclic C2–C6 alkenyl group, and at least one hydrogen atom in the alkyl group and alkenyl group in R¹ may be substituted with a substituent; L is one selected from the group consisting of a direct bond, a carbonyl oxy group, a carbonyl amino group, a phenylene diyl group, a naphthalene diyl group, a phenylene diyl oxy group, a naphthalene diyl oxy group, a phenylene diyl carbonyl oxy group, a naphthalene diyl carbonyl oxy group, a phenylene diyl oxy carbonyl group, and a naphthalene diyl oxy carbonyl group; Sp is one among a direct bond, a linear, branched, or cyclic C1–C6 alkylene group which may have a substituent, and a linear, branched, or cyclic C2–C6 alkenylene group which may have a substituent, and at least one methylene group in Sp may be substituted with a divalent heteroatom-containing group; M⁺ is a sulfonium cation group or an iodonium cation group; X^- is a monovalent anion group; f is an integer of 2-4, and f X^- bonded to R, f M⁺ corresponding to X^-, f R¹, f L, and f Sp may be respectively the same as or different from each other; and R is a C1-C6 f-valent hydrocarbon group which may have a substituent, at least one hydrogen atom in R may be substituted with a substituent, and at least one methylene group in R may be substituted with a divalent heteroatom-containing group.)

Description

Polymer, resist composition containing the polymer, method for manufacturing a member using the same, and method for forming a pattern

One embodiment of the present invention relates to a polymer used in a resist composition. Further, some embodiments of the present invention relate to a resist composition containing the above polymer, a method for producing a member using the resist composition, and a method for forming a pattern.

In recent years, the production of display devices such as liquid crystal displays (LCDs) and organic EL displays (OLEDs) and the formation of semiconductor elements have been actively carried out by making full use of photolithography technology using photoresists. In the above-mentioned electronic components and electronic product packages, active energy rays such as i-line with a wavelength of 365 nm, and longer wavelengths such as h-line (405 nm) and g-line (436 nm) are widely used.

As devices become more highly integrated, there is an increasing demand for miniaturization of lithography technology. There is a tendency for light with a very short wavelength such as (EB) to be used for exposure. Lithography techniques using these short-wavelength lights, especially EUV or electron beams, can be manufactured by single patterning, so there is a need for resist compositions that are highly sensitive to EUV or electron beams. It is thought that this will further increase in the future.

As exposure light sources become shorter in wavelength, resist compositions are required to have improved lithography properties such as sensitivity to the exposure light source and resolution capable of reproducing patterns with fine dimensions. A chemically amplified resist is known as a resist composition that satisfies such requirements (Patent Document 1).
However, in conventional chemically amplified resists, as the resolution line width of the resist becomes finer, it is difficult to sufficiently suppress resist pattern collapse and reduction in line edge roughness (LWR) of line patterns.

In order to suppress resist pattern collapse, it has been proposed to increase the crosslink density in negative chemically amplified resists. However, it may swell during development and cause defects such as bridges, making it difficult to maintain pattern performance and increase crosslink density with high sensitivity.

In order to suppress resist pattern collapse in chemically amplified resists, it has been proposed to reduce the resist film thickness (Non-Patent Document 1). Non-Patent Document 1 proposes a resist containing a metal such as tin as a method of reducing the resist film thickness and improving pattern characteristics.

Japanese Patent Application Publication No. 9-90637 JP2011-53622A JP2010-276910A Proc. of SPIE Vol. 11854 118540A-4 (2021)

In the method of Non-Patent Document 1, a pattern can be transferred in an etching process by utilizing the high etching resistance of metal in the resist, but there is a problem in terms of sufficient etching resistance. Furthermore, since Non-Patent Document 1 is a negative type resist, it is difficult to utilize it for a positive type resist pattern.
One aspect of the present invention is to provide a polymer for use in a resist composition that has high sensitivity, excellent development contrast characteristics, and high etching resistance.
Some aspects of the present invention aim to provide a resist composition containing the above polymer, a method for producing a member using the resist composition, and a method for forming a pattern.

As a result of intensive studies to solve the above problems, the present inventors found that unit A, which has a specific onium salt structure and generates acid upon irradiation with particle beams or electromagnetic waves, and Sn, Sb, Ge, Bi, and Te. By using a polymer containing an organometallic compound-containing unit B having a metal atom selected from the group as a polymer of a resist composition, the following (a) to (d) have been discovered, and some of the present invention has been achieved. We have now completed this aspect.
(a) Since the polymer contains the above unit A, not only can the acid generated from the onium salt of unit A be used for the reaction by irradiation with particle beams or electromagnetic waves, especially electron beams or EUV, but also the polymer decomposes due to the generation of acid. The molecular weight of the polymer decreases, making it easier to dissolve in the developer.
(b) The polymer contains the unit B and has etching resistance.
(c) The Lewis acidity of the metal used in unit B allows it to react with the acid generated from unit A, thereby suppressing the acid catalytic reaction, so that acid diffusion can be controlled.
(d) When the polymer containing the above unit A and the above unit B is used in a positive resist composition using an organic solvent as a developer, high development contrast can be maintained and exposed areas can be dissolved.

The unit A has an f-valent anion and f units each having a cation group corresponding to the f-valent anion, and the f units A are formed through bonding with the f-valent anion. It is characterized by being a group of units. By using a polymer having the above unit A and the above unit B, a resist composition containing the polymer becomes as follows when irradiated with a particle beam or an electromagnetic wave.
First, the unit A decomposes and a large polarity change occurs from ionic to nonionic. At the same time, due to the decomposition of the unit A, the f-valent anion is protonated to generate an acid. As a result, the polymer formed via the f-valent anion is decomposed and the crosslinked structure between polymer molecules is eliminated, resulting in a decrease in the polymer molecular weight and a change in the solubility of the polymer.
Resist compositions containing the above polymer can have high sensitivity and high development contrast without using acid diffusion, because in addition to polarity conversion due to decomposition of unit A, the solubility can be greatly changed by decomposition of the polymer. It is possible to obtain a pattern that maintains the
When the above polymer is used in a positive resist composition using an organic solvent as a developer, it can maintain high development contrast and dissolve exposed areas.

One aspect of the present invention that solves the above problem is a polymer that includes a unit A having an onium salt structure and generating an acid when irradiated with a particle beam or electromagnetic wave, and an organometallic compound-containing unit B having a metal atom selected from the group consisting of Sn, Sb, Ge, Bi and Te, and the unit A is represented by the following formula (1).

In the above general formula (1), R ¹ is a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms; and a linear, branched or cyclic alkenyl group having 2 to 6 carbon atoms; At least one hydrogen atom in the alkyl group and alkenyl group in R ¹ may be substituted with a substituent.

L is a direct bond, a carbonyloxy group, a carbonylamino group, a phenylenediyl group, a naphthalenediyl group, a phenylenediyloxy group, a naphthalenediyloxy group, a phenylenediylcarbonyloxy group, a naphthalenediylcarbonyloxy group, a phenylenediyloxycarbonyl group, and Any one selected from the group consisting of naphthalenediyloxycarbonyl groups.

Sp is a direct bond; a linear, branched or cyclic alkylene group having 1 to 6 carbon atoms which may have a substituent; and a straight chain, branched or cyclic carbon number which may have a substituent 2 to 6 alkenylene groups; at least one methylene group in Sp may be substituted with a divalent heteroatom-containing group.

M ⁺ is a sulfonium cation group or an iodonium cation group.
R is an f-valent hydrocarbon group having 1 to 6 carbon atoms which may have a substituent, and at least one hydrogen atom in R may be substituted with a substituent; One methylene group may be substituted with a divalent heteroatom-containing group.
X ⁻ is a monovalent anion group.
f is an integer from 2 to 4, and f X ⁻ bonded to the R, f M ⁺ corresponding to the X ⁻ , f R ¹ , f L and f Sp are: They may be the same or different from each other.

One embodiment of the present invention is a resist composition containing the above-mentioned polymer.
Another aspect of the present invention is a method for producing a member, the method including: a resist film formation step of forming a resist film on a substrate using the resist composition; a photolithography step of exposing the resist film using a particle beam or an electromagnetic wave; and a pattern formation step of developing the exposed resist film using a developer to dissolve the exposed portion, thereby obtaining a photoresist pattern.

One aspect of the present invention includes a resist film forming step of forming a resist film on a substrate using the above resist composition, a photolithography step of exposing the resist film to light using a particle beam or electromagnetic waves, and a step of exposing the resist film to light using a particle beam or electromagnetic waves. This pattern forming method includes a pattern forming step of developing a photoresist film using a developer to dissolve exposed areas and obtain a photoresist pattern.

（前記一般式（２）中、
Ｒ^１、Ｌ、Ｓｐ、Ｘ^－及びｆは、それぞれ前記一般式（１）のＲ^１、Ｌ、Ｓｐ、Ｘ^－及びｆと同じ選択肢から選択され、
Ｒ^６ａは、置換基を有していてもよい直鎖、分岐又は環状の炭素数１～６のアルキレン基；置換基を有していてもよい直鎖、分岐又は環状の炭素数２～６のアルケニレン基；置換基を有していてもよい炭素数６～１４のアリーレン基；置換基を有していてもよい炭素数４～１２のヘテロアリーレン基；及び直接結合；からなる群より選択されるいずれかであり、前記Ｒ^６ａ中の少なくとも１つのメチレン基が２価のヘテロ原子含有基で置換されていてもよく、
Ｒ^６ｂは、それぞれ独立に、置換基を有していてもよい直鎖、分岐又は環状の炭素数１～６のアルキル基；置換基を有していてもよい直鎖、分岐又は環状の炭素数２～６のアルケニル基；置換基を有していてもよい炭素数６～１４のアリール基；及び、置換基を有していてもよい炭素数４～１２のヘテロアリール基からなる群より選択されるいずれかであり、前記Ｒ^６ｂ中の少なくとも１つのメチレン基が２価のヘテロ原子含有基で置換されていてもよく、
Ｒ^６ａ及び２つのＲ^６ｂのうち２つは、単結合で直接に、又は、酸素原子、硫黄原子、２価の窒素原子含有基及びメチレン基からなる群より選択されるいずれかを介して、これらが結合している硫黄原子と環構造を形成してもよく、
前記Ｒに結合するｆ個のＸ^－、ｆ個のＲ^６ａ、ｆ個のＲ^６ｂ、ｆ個のＲ¹、ｆ個のＬ及びｆ個のＳｐは、それぞれ互いに同じであっても異なっていてもよい）
［４］
　前記Ｍ^＋が下記一般式（３）又は下記式（４）で示されるいずれかである［１］～［３］のいずれか一つに記載のポリマー。

（前記式（３）中、Ｒ^１１及びＲ^１２は独立して各々に、置換基を有していてもよい直鎖、分岐又は環状の炭素原子数１～１２のアルキル基；置換基を有していてもよい直鎖、分岐又は環状の炭素原子数２～１２のアルケニル基；置換基を有していてもよい炭素原子数６～１４のアリール基；及び置換基を有していてもよい炭素原子数４～１２のヘテロアリール基；からなる群より選択されるいずれかであり、
　前記Ｒ^1１、Ｒ^１２及びスルホニウム基が結合したアリール基のうちいずれか２つ以上は、単結合で直接に、又は、酸素原子、硫黄原子、２価の窒素原子含有基及びメチレン基からなる群より選択されるいずれかを介して、これらが結合する硫黄原子と共に環構造を形成してもよく、
　前記Ｒ^1１及びＲ^１２中の少なくとも１つのメチレン基が２価のヘテロ原子含有基で置換されていてもよく、
　Ｒ^１３及びＲ^１４は独立して各々に、アルキル基、ヒドロキシ基、メルカプト基、アルキレンオキシ基、アルキルカルボニル基、アリールカルボニル基、アルキレンオキシカルボニル基、アリールオキシカルボニル基、アリールスルファニルカルボニル基、アリールスルファニル基、アルキルスルファニル基、アリール基、ヘテロアリール基、アリールオキシ基、アルキルスルフィニル基、アリールスルフィニル基、アルキルスルホニル基、アリールスルホニル基、（メタ）アクリロイルオキシ基、ヒドロキシ（ポリ）アルキレンオキシ基、アミノ基、シアノ基、ニトロ基及びハロゲン原子からなる群より選択されるいずれかであり、炭素を有する場合の炭素原子数が１～１２であり、且つ、これらは置換基を有していてもよく、
　１つのＲ^１４が、直接結合、メチレン基、酸素原子、硫黄原子及び２価の窒素原子含有基からなる群より選択されるいずれかを介して該Ｒ^１４が結合するアリール基と共に互いに環構造を形成していてもよく、
　Ｒ^１５及びＲ^１６は独立して各々に、置換基を有していてもよい直鎖、分岐又は環状の炭素原子数１～１２のアルキル基；置換基を有していてもよい直鎖、分岐又は環状の炭素原子数２～１２のアルケニル基；置換基を有してもよい炭素原子数６～１４のアリール基；及び置換基を有していてもよい炭素原子数４～１２のヘテロアリール基；からなる群より選択されるいずれかであり、
　前記Ｒ^１５及びＲ^１６は、単結合で直接に、又は、酸素原子、硫黄原子及びアルキレン基からなる群より選択されるいずれかを介して、互いに結合して環構造を形成してもよく、
　前記Ｒ^１５及びＲ^１６中の少なくとも１つのメチレン基が２価のヘテロ原子含有基で置換されていてもよく、
　Ｌ^２は、直接結合；直鎖、分岐又は環状の炭素原子数１～１２のアルキレン基；炭素原子数２～１２のアルケニレン基；炭素原子数６～１４のアリーレン基；炭素原子数４～１２のヘテロアリーレン基；及びこれらの基が酸素原子、硫黄原子又は２価の窒素原子含有基を介して結合した基；からなる群より選択されるいずれかであり、
　Ｌ^３は、直接結合、メチレン基、硫黄原子、２価の窒素原子含有基、及び酸素原子からなる群より選択され、
　Ｙは酸素原子又は硫黄原子であり、
　ｈは１～２の整数であり、
　iは１～３の整数であり、
　ｊは、ｈが１のとき０～３、ｈが２のとき０～５の整数であり、
　ｋは、ｉが１のとき０～４、iが２のとき０～６、iが３のとき０～８の整数であり、

　Ｒ^１１、Ｒ^１２及びＲ^１４の中のいずれかの１つの水素並びにＲ^１４が結合するアリール環上の水素原子が、上記式（１）中のＳｐとの結合に置き換えられ、
　前記式（４）中、Ｒ^１１～Ｒ^１６、Ｌ^２及びＹは独立して各々に、前記式（３）のＲ^１１～Ｒ^１６、Ｌ^２及びＹ各々と同じ選択肢から選択され、
　ｈは１～２の整数であり、
　iは１～３の整数であり、
　ｊは、ｈが１のとき０～４、ｈが２のとき０～６の整数であり、
　ｋは、ｉが１のとき０～５、ｉが２のとき０～７、ｉが３のとき０～９の整数であり、
　Ｌ^４及びＬ^５は独立して各々に、直接結合、炭素原子数が２のアルケニレン基、炭素原子数が２のアルキニレン基、及びカルボニル基からなる群より選択されるいずれかである。））
［５］
　ユニットＤをさらに有し、上記ユニットＤが下記式（６）で示される［１］～［４］のいずれか一項に記載のポリマー。

（上記一般式（６）中、Ｒ^１、Ｌ、Ｓｐ、Ｍ^＋は、上記一般式（１）に記載のＲ^１、Ｌ、Ｓｐ、Ｍ^＋と同様の選択肢から選択され、Ｚ^－は１価のアニオンである。）
［６］
　前記ユニットＡに対するユニットＤのモル比が０～２０である［１］～［５］のいずれか一つに記載のポリマー。
［７］
　ユニットＣをさらに有し、前記ユニットＣが、下記一般式（Ｉ）又は（ＩＩ）で示される化合物が該化合物のいずれかの位置で下記式（５）のＳｐ基と結合したユニットである［１］～［６］のいずれか一つに記載のポリマー。

（前記一般式（Ｉ）中、
Ｒ^２及びＲ^３は、それぞれ独立に、水素原子；電子供与性基；及び電子吸引性基；からなる群より選択されるいずれかであり、
Ｅは、直接結合；酸素原子；硫黄原子；及びメチレン基；からなる群より選択されるいずれかであり、
Ｒ^４は置換基を有してもよいアルキル基；及び置換基を有してもよいアルケニル基；からなる群より選択されるいずれかであり、
ｎ^１は、０又は１の整数であり、
ｎ^４及びｎ^５は、それぞれ１～２の整数であり、ｎ^４＋ｎ^５は２～４であり、
ｎ^４が１のときｎ^２は０～４の整数であり、ｎ^４が２のときｎ^２は０～６の整数であり、
ｎ^５が１のときｎ^３は０～４の整数であり、ｎ^５が２のときｎ^３は０～６の整数であり、
ｎ^２が２以上でＲ^２が電子供与性基又は電子吸引性基であるとき、２つのＲ^２が、単結合で直接に、又は、酸素原子、硫黄原子、２価の窒素原子含有基及びメチレン基からなる群より選択されるいずれかを介して、互いに環構造を形成してもよく、
ｎ^３が２以上でＲ^３が電子供与性基又は電子吸引性基であるとき、２つのＲ^３が、単結合で直接に、又は、酸素原子、硫黄原子、２価の窒素原子含有基及びメチレン基からなる群より選択されるいずれかを介して、互いに環構造を形成してもよい。
前記一般式（ＩＩ）中、
Ｒ^４は置換基を有してもよいアルキル基；及び置換基を有してもよいアルケニル基；からなる群より選択されるいずれかであり、
Ｒ^５は、水素原子；置換基を有してもよいアルキル基；及び置換基を有してもよいアルケニル基；からなる群より選択されるいずれかであり、前記Ｒ^５中の少なくとも１つのメチレン基が２価のヘテロ原子含有基で置換されていてもよく、前記Ｒ^５は該Ｒ^５を有するヒドロキシメチレン基が結合したベンゼン環と共に環構造を形成してもよく、
Ｒ^６は、それぞれ独立に、水素原子；電子供与性基；及び電子吸引性基；からなる群より選択されるいずれかであり、
Ｒ^６のうち少なくとも一つは前記電子供与性基であり、
ｎ^６は０～７の整数であり、
ｎ^７は１又は２であり、ｎ^７が１のときｎ^６は０～５の整数であり、ｎ^７が２のときｎ^６は０～７の整数であり、
ｎ^６が２以上でＲ^４が電子供与性基又は電子吸引性基であるとき、２つのＲ^４が、単結合で直接に、又は、酸素原子、硫黄原子、２価の窒素原子含有基及びメチレン基からなる群より選択されるいずれかを介して、互いに環構造を形成してもよい。）

（前記式（５）中、
Ｒ^１、Ｌ及びＳｐは、それぞれ前記一般式（１）のＲ^１、Ｌ及びＳｐと同じ選択肢から選択され、
＊は前記一般式（Ｉ）又は（ＩＩ）で示される化合物との結合部位を示す。）
［８］
　［１］～［７］のいずれか一つに記載のポリマーを含有するレジスト組成物。
［９］
　［８］に記載のレジスト組成物を用いて基板上にレジスト膜を形成するレジスト膜形成工程と、
　粒子線又は電磁波を用いて、前記レジスト膜を露光するフォトリソグラフィ工程と、
　露光されたレジスト膜を現像液を用いて現像することで露光部を溶解してフォトレジストパターンを得るパターン形成工程と、
を含む部材の製造方法。
［１０］
　前記現像液が有機溶剤である［９］に記載の部材の製造方法。
［１１］
　前記フォトリソグラフィ工程において、前記粒子線又は電磁波の露光後に前記粒子線又は電磁波よりも低いエネルギーである第２活性エネルギー線をさらに照射する、［９］又は［１０］に記載の部材の製造方法。
［１２］
　前記粒子線が電子線であり、前記電磁波が極端紫外線である、［９］～［１１］のいずれか一つに記載の部材の製造方法。
［１３］
　［８］に記載のレジスト組成物を用いて基板上にレジスト膜を形成するレジスト膜形成工程と、
　粒子線又は電磁波を用いて、前記レジスト膜を露光するフォトリソグラフィ工程と、
　露光されたレジスト膜を現像液を用いて現像することで露光部を溶解してフォトレジストパターンを得るパターン形成工程と、を含むパターン形成方法。
［１４］
　前記現像液が有機溶剤である［１３］に記載のパターン形成方法。
［１５］
　前記フォトリソグラフィ工程において、前記粒子線又は電磁波の露光後に前記粒子線又は電磁波よりも低いエネルギーである第２活性エネルギー線をさらに照射する、［１３］又は［１４］に記載のパターン形成方法。 Below, various aspects of the present invention will be illustrated. The embodiments shown below can be combined with each other.
[1]
A unit A that has an onium salt structure and generates acid by irradiation with particle beams or electromagnetic waves;
an organometallic compound-containing unit B having a metal atom selected from the group consisting of Sn, Sb, Ge, Bi and Te;
A polymer in which the unit A is represented by the above formula (1).
[2]
A group in which X ^- is an alkyl sulfate anion; an aryl sulfate anion; an alkyl sulfonate anion; an aryl sulfonate anion; an alkyl carboxylate anion; an aryl carboxylate anion; a dialkyl sulfonylimide anion; a trialkyl sulfonate methide anion; a tetrakis phenyl borate anion; one selected from
At least one hydrogen atom of the alkyl group and aryl group in X ^- may be substituted with a substituent, and at least one methylene group in the alkyl group in X ^- may be substituted with a divalent heteroatom-containing group. The polymer according to [1], which may be
[3]
The polymer according to [1] or [2], wherein the unit A is represented by the following formula (2).

(In the general formula (2),
R ¹ , L, Sp, X ⁻ and f are each selected from the same options as R ¹ , L, Sp, X ⁻ and f in the general formula (1),
R ^6a is a straight chain, branched or cyclic alkylene group having 1 to 6 carbon atoms that may have a substituent; a straight chain, branched or cyclic alkylene group having 2 to 6 carbon atoms that may have a substituent; selected from the group consisting of an alkenylene group; an arylene group having 6 to 14 carbon atoms which may have a substituent; a heteroarylene group having 4 to 12 carbon atoms which may have a substituent; and a direct bond. and at least one methylene group in R ^6a may be substituted with a divalent heteroatom-containing group,
R ^6b is each independently a straight chain, branched or cyclic alkyl group having 1 to 6 carbon atoms which may have a substituent; a straight chain, branched or cyclic carbon atom which may have a substituent; From the group consisting of an alkenyl group having 2 to 6 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and a heteroaryl group having 4 to 12 carbon atoms which may have a substituent At least one methylene group in R ^6b may be substituted with a divalent heteroatom-containing group,
Two of R ^6a and two R ^6b are directly a single bond, or via one selected from the group consisting of an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and a methylene group, These may form a ring structure with the sulfur atom to which they are bonded,
The f X ^{− s} , f R ^6a s, f R ^6b s, f R ¹ s, f Ls, and f Sps bonded to R may be the same or different from each other. good)
[4]
The polymer according to any one of [1] to [3], wherein the M ⁺ is represented by the following general formula (3) or the following formula (4).

(In the above formula (3), R ¹¹ and R ¹² each independently represent a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; A straight chain, branched or cyclic alkenyl group having 2 to 12 carbon atoms which may have a substituent; an aryl group having 6 to 14 carbon atoms which may have a substituent; a heteroaryl group having 4 to 12 carbon atoms;
Any two or more of the aryl groups to which R ¹¹ , R ¹² and the sulfonium group are bonded may be directly bonded by a single bond, or may be a group consisting of an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and a methylene group. These may form a ring structure together with the sulfur atom to which they are bonded via any one selected from
At least one methylene group in R ¹¹ and R ¹² may be substituted with a divalent heteroatom-containing group,
R ¹³ and R ¹⁴ independently each represent an alkyl group, a hydroxy group, a mercapto group, an alkyleneoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkyleneoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group. group, alkylsulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, (meth)acryloyloxy group, hydroxy(poly)alkyleneoxy group, amino group , a cyano group, a nitro group, and a halogen atom, and if it has carbon, the number of carbon atoms is 1 to 12, and these may have a substituent,
One R ¹⁴ forms a ring structure with the aryl group to which the R ¹⁴ is bonded via any one selected from the group consisting of a direct bond, a methylene group, an oxygen atom, a sulfur atom, and a divalent nitrogen atom-containing group. It may be formed,
R ¹⁵ and R ¹⁶ each independently represent a straight chain, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; a straight chain which may have a substituent; A branched or cyclic alkenyl group having 2 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and a hetero group having 4 to 12 carbon atoms which may have a substituent Any one selected from the group consisting of: aryl group;
The R ¹⁵ and R ¹⁶ may be bonded to each other to form a ring structure directly with a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and an alkylene group,
At least one methylene group in R ¹⁵ and R ¹⁶ may be substituted with a divalent heteroatom-containing group,
L ² is a direct bond; a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms; an alkenylene group having 2 to 12 carbon atoms; an arylene group having 6 to 14 carbon atoms; 4 to 12 carbon atoms a heteroarylene group; and a group in which these groups are bonded via an oxygen atom, a sulfur atom, or a divalent nitrogen atom-containing group;
^L3 is selected from the group consisting of a direct bond, a methylene group, a sulfur atom, a divalent nitrogen atom-containing group, and an oxygen atom,
Y is an oxygen atom or a sulfur atom,
h is an integer from 1 to 2,
i is an integer from 1 to 3,
j is an integer from 0 to 3 when h is 1, and from 0 to 5 when h is 2;
k is an integer from 0 to 4 when i is 1, from 0 to 6 when i is 2, and from 0 to 8 when i is 3;

Any one hydrogen among R ¹¹ , R ¹² and R ¹⁴ and the hydrogen atom on the aryl ring to which R ¹⁴ is bonded are replaced by a bond with Sp in the above formula (1),
In the formula (4), R ¹¹ to R ¹⁶ , L ² and Y are each independently selected from the same options as each of R ¹¹ to R ¹⁶ , L ² and Y in the formula (3),
h is an integer from 1 to 2,
i is an integer from 1 to 3,
j is an integer from 0 to 4 when h is 1, and from 0 to 6 when h is 2;
k is an integer from 0 to 5 when i is 1, from 0 to 7 when i is 2, and from 0 to 9 when i is 3;
L ⁴ and L ⁵ are each independently selected from the group consisting of a direct bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, and a carbonyl group. ))
[5]
The polymer according to any one of [1] to [4], further comprising a unit D, wherein the unit D is represented by the following formula (6).

(In the above general formula (6), R ¹ , L, Sp, M ⁺ are selected from the same options as R ¹ , L, Sp, M ⁺ described in the above general formula (1), and Z ⁻ is 1 (It is an anion of valence.)
[6]
The polymer according to any one of [1] to [5], wherein the molar ratio of unit D to unit A is 0 to 20.
[7]
[ 1] to [6].

(In the general formula (I),
R ² and R ³ are each independently selected from the group consisting of a hydrogen atom; an electron-donating group; and an electron-withdrawing group;
E is any one selected from the group consisting of a direct bond; an oxygen atom; a sulfur atom; and a methylene group;
R ⁴ is any one selected from the group consisting of an alkyl group that may have a substituent; and an alkenyl group that may have a substituent;
n ¹ is an integer of 0 or 1,
n ⁴ and n ⁵ are each an integer of 1 to 2, n ⁴ + n ⁵ is 2 to 4,
When n ⁴ is 1, n ² is an integer from 0 to 4; when n ⁴ is 2, n ² is an integer from 0 to 6;
When n ⁵ is 1, n ³ is an integer from 0 to 4; when n ⁵ is 2, n ³ is an integer from 0 to 6;
When n ² is 2 or more and R ² is an electron-donating group or an electron-withdrawing group, the two R ^2s are directly connected by a single bond, or an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and A ring structure may be formed with each other via any one selected from the group consisting of methylene groups,
When n ³ is 2 or more and R ³ is an electron-donating group or an electron-withdrawing group, two R ^3s are directly connected to each other by a single bond, or an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and A ring structure may be formed with each other via any one selected from the group consisting of methylene groups.
In the general formula (II),
R ⁴ is any one selected from the group consisting of an alkyl group that may have a substituent; and an alkenyl group that may have a substituent;
R ⁵ is any one selected from the group consisting of a hydrogen atom; an alkyl group that may have a substituent; and an alkenyl group that may have a substituent; and at least one of the R ⁵ The methylene group may be substituted with a divalent heteroatom-containing group, and the R ⁵ may form a ring structure together with a benzene ring to which the hydroxymethylene group having the R ⁵ is bonded,
R ⁶ is each independently selected from the group consisting of a hydrogen atom; an electron-donating group; and an electron-withdrawing group;
At least one of R ⁶ is the electron donating group,
n ⁶ is an integer from 0 to 7,
ⁿ⁷ is 1 or 2; when ⁿ⁷ is 1, ⁿ⁶ is an integer from 0 to 5; when ⁿ⁷ is 2, ⁿ⁶ is an integer from 0 to 7;
When n ⁶ is 2 or more and R ⁴ is an electron-donating group or an electron-withdrawing group, two R ^4s are directly connected to each other by a single bond, or an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and A ring structure may be formed with each other via any one selected from the group consisting of methylene groups. )

(In the above formula (5),
R ¹ , L and Sp are each selected from the same options as R ¹ , L and Sp in the general formula (1),
* indicates a bonding site with the compound represented by the general formula (I) or (II). )
[8]
A resist composition containing the polymer according to any one of [1] to [7].
[9]
a resist film forming step of forming a resist film on a substrate using the resist composition described in [8];
a photolithography step of exposing the resist film using particle beams or electromagnetic waves;
a pattern forming step of developing the exposed resist film using a developer to dissolve the exposed area and obtain a photoresist pattern;
A method for manufacturing a member including.
[10]
The method for producing a member according to [9], wherein the developer is an organic solvent.
[11]
The method for producing a member according to [9] or [10], wherein in the photolithography step, after exposure to the particle beam or electromagnetic wave, a second active energy ray having a lower energy than the particle beam or electromagnetic wave is further irradiated.
[12]
The method for producing a member according to any one of [9] to [11], wherein the particle beam is an electron beam and the electromagnetic wave is extreme ultraviolet rays.
[13]
a resist film forming step of forming a resist film on a substrate using the resist composition described in [8];
a photolithography step of exposing the resist film using particle beams or electromagnetic waves;
A pattern forming method comprising a pattern forming step of developing the exposed resist film using a developer to dissolve exposed areas and obtain a photoresist pattern.
[14]
The pattern forming method according to [13], wherein the developer is an organic solvent.
[15]
The pattern forming method according to [13] or [14], wherein in the photolithography step, after exposure to the particle beam or electromagnetic wave, a second active energy ray having a lower energy than the particle beam or electromagnetic wave is further irradiated.

When the polymer of one embodiment of the present invention is used as a resist composition, in addition to being decomposed and polarized by irradiation with particle beams or electromagnetic waves, the f-valent anion is protonated to generate acid. . As a result, the polymer formed through the anions is decomposed and the crosslinked structure between polymer molecules is eliminated, thereby changing the solubility of the polymer. Therefore, in a resist composition containing the above polymer, the solubility can be greatly changed by decomposing the polymer in addition to the polarity conversion due to the decomposition of unit A, and pattern formation using the polymer according to one embodiment of the present invention. When this is done, the sensitivity and development contrast characteristics are excellent.

In the present invention, "particle beam or electromagnetic wave" includes not only electron beams and extreme ultraviolet rays but also ultraviolet rays, and preferably electron beams or extreme ultraviolet rays.
In the present invention, "particle beam or electromagnetic wave irradiation" refers to irradiating at least a part of the polymer with a particle beam or electromagnetic wave. When a part of the polymer is irradiated with particle beams or electromagnetic waves, a specific part of the polymer is excited or ionized, and active species are generated. At least one of the following secondary reactions, such as decomposition of a part of the unit by the active species, addition of the active species to the unit, and desorption of hydrogen from the unit by the active species, is carried out. radicals or acids are generated. Here, "active species" refers to radical cations, radicals, electrons, and the like.
In the present invention, "polarity conversion" refers to changing from ionicity to nonionicity and improving hydrophobicity, directly or indirectly, by irradiation with particle beams or electromagnetic waves.
The present invention will be described in detail below, but the present invention is not limited thereto.

<1> Polymer The polymer that is one embodiment of the present invention has a specific onium salt structure and consists of a unit A that generates an acid upon irradiation with particle beams or electromagnetic waves, and Sn, Sb, Ge, Bi, and Te. and an organometallic compound-containing unit B having a metal atom selected from the group B.

(Unit A)
The unit A has a specific onium salt structure. Specifically, the onium salt structure undergoes polarity conversion by irradiating at least a portion of the polymer with particle beams or electromagnetic waves. That is, the unit A has an f-valent anion and f units having a cation group corresponding to the f-valent anion, and is a unit group in which the f units are bonded to each other by the f-valent anion. It is characterized by
Specifically, for example, those represented by the following formula (1) can be mentioned.

In the above general formula (1), M ⁺ is a sulfonium cation group or an iodonium cation group.

L is not particularly limited as long as it can bond the main chain constituting the polymer with the above-mentioned onium salt structure, but in addition to direct bonding, for example, L can be a carbonyloxy group, a carbonylamino group, a phenylenediyl group, a naphthalenediyl group, or a phenylenediyloxy group. , naphthalenediyloxy group, phenylenediylcarbonyloxy group, naphthalenediylcarbonyloxy group, phenylenediyloxycarbonyl group, naphthalenediyloxycarbonyl group, and the like.
L is preferably a carbonyloxy group or the like from the viewpoint of easy synthesis.

Sp is not particularly limited as long as it can serve as a spacer between the above-mentioned L and the above-mentioned onium salt; for example, a direct bond; a linear, branched or cyclic carbon number 1-6 which may have a substituent; an alkylene group; and a linear, branched or cyclic alkenylene group having 2 to 6 carbon atoms which may have a substituent; and at least one methylene group in the above Sp is a divalent hetero It may be substituted with an atom-containing group.

Examples of the straight chain alkylene group having 1 to 6 carbon atoms for Sp include methylene group, ethylene group, n-propylene group, n-butylene group, n-pentylene group and n-hexylene group.
Examples of the branched alkylene group having 1 to 6 carbon atoms for Sp include isopropylene group, isobutylene group, tert-butylene group, isopentylene group, tert-pentylene group, and 2-ethylhexylene group.

Examples of the cyclic alkylene group having 1 to 6 carbon atoms for Sp include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, and a cyclohexylene group.
At least one methylene group in Sp may be substituted with a divalent heteroatom-containing group. Examples of divalent heteroatom-containing groups include -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH-CO-O-, A group selected from the group consisting of -O-CO-NH-, -NH-, -N(R ^Sp )-, -N(Ar ^Sp )-, -S-, -SO-, -SO ₂ -, etc. Can be mentioned. However, it is preferable that there is no continuous chain of hetero atoms such as -O-O-, -S-S-, and -O-S-, and that at least one methylene group is substituted with a divalent hetero atom-containing group. Examples of the Sp include 2-methoxyethoxy group, 2-ethoxyethoxy group, 2-(2-methoxyethoxy)ethoxy group, 2-(2-ethoxyethoxy)ethoxy group, 2-methoxypropoxy group, and 3-methoxyethoxy group. Polyalkyleneoxy groups such as methoxypropoxy groups; polyalkylenethio groups such as 2-methylthioethylthio and 2-ethylthioethylthio groups; and polyalkyleneoxythio groups such as 2-methylthioethoxy and 2-ethoxyethylthio groups. ; etc. However, some aspects of the invention are not so limited.
Examples of the R ^Sp include linear, branched, or cyclic alkyl groups having 1 to 12 carbon atoms, and examples of Ar ^Sp include aryl groups having 12 or less carbon atoms such as phenyl and naphthyl groups.

Examples of the substituent that Sp may have (hereinafter also referred to as "first substituent") include halogen atoms such as fluorine atom, chlorine atom, bromine atom, or iodine atom; hydroxy group; linear or cyclic carbon atom; Alkyl group of number 1 to 12; -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH in place of at least one methylene group of the alkyl group -, -NH-CO-O-, -O-CO-NH-, -NH-, -N(R ^Sp )-, -N(Ar ^Sp )-, -S-, -SO- and -SO ₂ ^- Examples include an alkyl group whose skeleton contains one type of divalent heteroatom-containing group selected from the group consisting of; an aryl group; and a heteroaryl group.
Note that the above R ^Sp and Ar ^Sp can be the first substituent. When Sp has the first substituent, the number of carbon atoms in Sp is preferably 1 to 6, including the number of carbon atoms in the first substituent.
Examples of the alkyl group as the first substituent of Sp and the alkyl group containing the divalent heteroatom-containing group in the skeleton include an alkyl group in which the alkylene group of Sp is monovalent.
Examples of the aryl group as the first substituent of Sp include those similar to the above Ar ^Sp .
Examples of the heteroaryl group as the first substituent of Sp include groups having a skeleton such as furan, thiophene, pyrrole, imidazole, pyran, pyridine, pyrimidine, and pyrazine.
Sp may be a direct bond, but preferably has a spacer structure so that the molecule can move easily. Preferred examples include alkylene group, alkyleneoxy group, and alkylenecarbonyloxy group.

R ¹ is any one selected from the group consisting of a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms; and a linear, branched or cyclic alkenyl group having 2 to 6 carbon atoms; and at least one hydrogen atom in the alkyl group and alkenyl group in R ¹ may be substituted with a substituent. Examples of the substituent that R ¹ may have include those similar to the first substituent described above.

Examples of the linear alkyl group having 1 to 6 carbon atoms for R ¹ include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group and n-hexyl group.
Examples of the branched alkyl group having 1 to 6 carbon atoms for R ¹ include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, tert-pentyl group, and 2-ethylexyl group.
Examples of the cyclic alkyl group having 1 to 6 carbon atoms for R ¹ include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group.

As the straight chain, branched or cyclic alkenyl group having 2 to 6 carbon atoms for R ¹ , at least one of the carbon-carbon single bonds of the straight-chain alkyl group, branched alkyl group and cyclic alkyl group shown above is a carbon-carbon Examples include those substituted with a double bond.
Furthermore, R ¹ may be a fluorinated alkyl group or a fluorinated alkenyl group in which at least one hydrogen atom in the alkyl group or alkenyl group is substituted with a fluorine atom. As the fluorinated alkyl group, a trifluoromethyl group and the like are preferred.
All hydrogen atoms may be substituted with the above-mentioned first substituent. When R ¹ has the above first substituent, the number of carbon atoms in R ¹ including the number of carbon atoms in the first substituent is preferably 1 to 6.

Preferably, the above unit A includes those in the above formula (1) in which R ¹ is a hydrogen atom or a linear alkyl group, and is an L carbonyloxy group, a carbonylamino group, or a phenylenediyl group.
Further, as the unit A, L is a carbonyloxy group or a carbonylamino group, Sp is a direct bond, R ¹ is a methyl group, and the methyl group is a carbon A unit having at least one of several alkyl groups, halogen atoms, and aryl groups is preferable from the viewpoint of LWR. Particularly preferable examples of R ¹ having the first substituent include ethyl group, isopropyl group, butyl group, halogenated methyl group (fluoromethyl group, chloromethyl group, bromomethyl group, iodomethyl group, etc.), and benzyl group. Can be mentioned.

M ⁺ is a sulfonium cation group or an iodonium cation group having a bond bonding to Sp, and specifically includes those shown in the following general formulas (a1) and (a2).

In the polymer of one embodiment of the present invention, the unit A is preferably represented by the following formula (2).

In the above general formula, R ^6a is a straight chain, branched or cyclic alkylene group having 1 to 6 carbon atoms which may have a substituent; An alkenylene group having 2 to 6 carbon atoms; an arylene group having 6 to 14 carbon atoms which may have a substituent; a heteroarylene group having 4 to 12 carbon atoms which may have a substituent; and a direct bond; Any one selected from the group consisting of.
Examples of the linear, branched or cyclic alkylene group for R ^6a include those similar to the alkylene group for Sp above.
Examples of the linear, branched or cyclic alkenylene group for R ^6a include those similar to the alkenylene group for Sp above.

Examples of the arylene group having 6 to 14 carbon atoms for R ^6a include a phenylene group and a naphthylene group.
Examples of the heteroarylene group having 4 to 12 carbon atoms for R ^6a include furan, thiophene, pyrrole, imidazole, pyran, pyridine, pyrimidine, pyrazine, indole, purine, quinoline, isoquinoline, chromene, thianthrene, dibenzothiophene, phenothiazine, and phenoxazine. , xanthene, acridine, phenazine, carbazole, and other divalent groups having a skeleton.
Examples of the alkyl group, alkenyl group, aryl group, and heteroaryl group of R ^6b include monovalent alkylene, alkenylene, arylene, and heteroarylene groups of R ^6a .

Examples of the substituents for R ^6a and R ^6b include the same substituents as the first substituent that Sp may have. When R ^6a and R ^6b have the above first substituent, the number of carbon atoms in R ^6a and R ^6b , including the number of carbon atoms in the first substituent, is preferably 1 to 6.
In the above formula (a1), any two of R ^6a and two R ^6b are single bonds directly, or from the group consisting of an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and a methylene group. These may form a ring structure together with the sulfur atom to which they are bonded via any selected link.
Examples of the divalent nitrogen atom-containing group include those containing a nitrogen atom among the divalent heteroatom-containing groups, and specifically, -NHCO-, -CONH-, -NH-CO- Examples include O-, -O-CO-NH-, -NH-, -N(R ^Sp )-, and -N(Ar ^Sp )-.

Examples of the sulfonium cation group as M ⁺ include monovalent groups having a bond bonding to Sp at any position in the structure shown below. In addition, the compounds shown below may have the above-mentioned substituents in the portions corresponding to the above-mentioned R ^6a and R ^6b .

The anion of unit A is an f-valent anion. Specifically, it is an f-valent anion represented by R(X ⁻ ) _f .
R is an f-valent hydrocarbon group having 1 to 6 carbon atoms, and at least one hydrogen atom in R may be substituted with a substituent (hereinafter also referred to as "second substituent"). Examples of the divalent hydrocarbon group when f is 2 include an alkylene group, an arylene group, a heteroarylene group, and the like. Examples of the trivalent hydrocarbon group when f is 3 include those obtained by making the above divalent substituent trivalent. Examples of the second substituent include, in addition to the first substituent, an amino group and the like. The second substituent is preferably a fluorine atom or the like.

X ^- is a monovalent anion group, which includes alkyl sulfate anion; aryl sulfate anion; alkyl sulfonate anion; aryl sulfonate anion; alkyl carboxylate anion; aryl carboxylate anion; dialkyl sulfonylimide anion; trialkyl sulfonate methide anion; tetrakis Phenylborate anion; At least one of the hydrogen atoms of the alkyl group and aryl group in X- may be substituted with the second substituent.
The f X ^-s in the f-valent anion may be the same or different.
When a methylene group is present in R and X 2 ^- , at least one of the methylene groups may be substituted with the above-mentioned divalent heteroatom-containing group. Examples of the divalent heteroatom-containing group include the same divalent heteroatom-containing group as in Sp.

The alkyl sulfate anion, alkyl sulfonate anion, dialkyl sulfonylimide anion, and trialkyl sulfonate methide anion preferably have 1 to 12 carbon atoms. The aryl sulfate anion and the aryl sulfonate anion preferably have 4 to 12 carbon atoms.
The alkyl carboxylate anion preferably has 2 to 12 carbon atoms. The aryl carboxylate anion preferably has 5 to 12 carbon atoms. The tetrakis phenylborate anion preferably has 25 to 30 carbon atoms.

The above unit A has an f-valent anion. Specific examples of the f-valent anion include, but are not limited to, the following.

In the polymer of one embodiment of the present invention, it is also preferable from the viewpoint of sensitivity that the M ⁺ in the unit A is represented by the following general formula (3) or the following formula (4). Since the M ⁺ has an acetal site or a thioacetal site, in the photolithography process, after exposure to the particle beam or electromagnetic wave, when a second active energy ray having a lower energy than the particle beam or electromagnetic wave is further irradiated, Since the decomposition of the unit A is promoted, high sensitivity can be achieved.

Specifically, since M ⁺ of the onium salt of unit A has an acetal moiety or a thioacetal moiety, it does not have significant absorption of the second active energy rays such as ultraviolet rays or visible light. On the other hand, the acetal moiety or thioacetal moiety of the onium salt is deprotected by the acid generated by the first active energy ray, such as a particle beam or electromagnetic wave, without impairing the function of the onium salt as a photoacid generator. is converted to a ketone derivative. The ketone derivative absorbs the first active energy ray and the second active energy ray.

Therefore, when the polymer of one embodiment of the present invention in which the above M ⁺ is represented by either the above general formula (3) or the above formula (4) is used as a resist composition, it is difficult to absorb particle beams, electromagnetic waves, etc. By irradiating with the first energy beam, the onium salt structure of the unit A is decomposed, a large polarity change from ionic to nonionic occurs, and acid is generated. Further, the onium salt structure of the unit A in the composition irradiated with the first active energy ray is structurally changed by the acid and converted into a ketone derivative that absorbs the second active energy ray. By irradiating the above-mentioned composition in which the above-mentioned ketone derivative has been generated with a second active energy ray such as ultraviolet rays or visible light, acid is generated with high efficiency, so that the above-mentioned composition has high sensitivity and pattern characteristics such as LWR. Excellent. From this, the polymer of one aspect of the present invention has two-stage irradiation in which, after irradiation with the first active energy ray, the part irradiated with the first active energy ray is irradiated with the second active energy ray. It is preferable to use it in the process. Since the above-mentioned ketone derivative is generated in the resist film at the irradiated area where the first active energy ray is irradiated, acid is generated at the irradiated area by the first active energy ray by further irradiating the second active energy ray. The amount can be increased.

In the above formula (3), R ¹¹ and R ¹² each independently represent a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; a straight chain, branched or cyclic alkenyl group having 2 to 12 carbon atoms which may have a substituent; an aryl group having 6 to 14 carbon atoms which may have a substituent; and a substituent which may have a substituent. Any one selected from the group consisting of: a heteroaryl group having 4 to 12 carbon atoms;
At least one methylene group in R ¹¹ and R ¹² may be substituted with a divalent heteroatom-containing group. Examples of the divalent heteroatom-containing group include those similar to the divalent heteroatom-containing group in Sp.

Any two or more of the above R ¹¹ , R ¹² and the aryl group to which the sulfonium group is bonded may be directly bonded through a single bond, or may be a group consisting of an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and a methylene group. These may form a ring structure together with the sulfur atom to which they are bonded via any one selected from the above.
Examples of the divalent nitrogen atom-containing group include divalent groups containing a nitrogen atom among the divalent heteroatom-containing groups.

Examples of the substituent in R ¹¹ and R ¹² (hereinafter also referred to as "third substituent") include a hydroxy group, a cyano group, a mercapto group, a carboxy group, an alkyl group (-R ^e ), an alkoxy group (-OR ^e ), acyl group (-COR ^e ), alkoxycarbonyl group (-COOR ^e ), aryl group (-Ar), aryloxy group (-OAr), amino group, alkylamino group (-NHR ^e ), dialkylamino group (- N(R ^e ) ₂ ), arylamino group (-NHAr), diarylamino group (-N(Ar) ₂ ), N-alkyl-N-arylamino group (-NR ^e Ar) phosphino group, silyl group, halogen atom, a trialkylsilyl group (-Si-(R ^e ) ₃ ), a silyl group in which at least one alkyl group of the trialkylsilyl group is substituted with Ar, an alkylsulfanyl group (-SR ^e ), and an arylsulfanyl group ( -SAr), but are not limited to these.
R ^e and Ar will be explained below.

The R ^e in the third substituent is preferably an alkyl group having 1 or more carbon atoms. Moreover, it is more preferable that the number of carbon atoms is 20 or less. Specific examples of alkyl groups having one or more carbon atoms include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-octyl group, and n-decyl group. Linear alkyl groups such as groups; branched alkyl groups such as isopropyl group, isobutyl group, tert-butyl group, isopentyl group, tert-pentyl group, 2-ethylexyl group; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl alicyclic alkyl groups such as adamantan-1-yl, adamantan-2-yl, norbornan-1-yl and norbornan-2-yl groups; one of these hydrogens is trimethylsilyl, triethylsilyl and Preferred examples include a silyl group-substituted alkyl group substituted with a trialkylsilyl group such as a dimethylethylsilyl group; an alkyl group in which at least one of these hydrogen atoms is substituted with a cyano group or a fluoro group; and the like. The carbon-carbon single bond in the alkyl group may be replaced with a carbon-carbon double bond.

Ar in the third substituent is preferably an aryl group or a heteroaryl group. The heteroaryl group is preferably an aryl group containing one or more heteroatoms in the ring structure. Specific examples of the above aryl group or heteroaryl group include phenyl group, biphenyl group, terphenyl group, quaterphenyl group, naphthyl group, anthryl group, phenanthrenyl group, pentalenyl group, indenyl group, indacenyl group, acenaphthyl group, fluorenyl group. group, heptarenyl group, naphthacenyl group, pyrenyl group, chrysenyl group, tetracenyl group, furanyl group, thienyl group, pyranyl group, sulfanylpyranyl group, pyrrolyl group, imidazoyl group, oxazolyl group, thiazolyl group, pyrazoyl group, pyridyl group, iso Benzofuranyl group, benzofuranyl group, isochromenyl group, chromenyl group, indolyl group, isoindolyl group, benzimidazoyl group, xanthenyl group, aquazinyl group, carbazol group, furan group, thiophene group, pyrrole group, imidazole group, pyran group, pyridine Preferable examples include those having 20 or less carbon atoms, such as a pyrimidine group, a pyrimidine group, and a pyrazine group.

The third substituent may be a group further having a third substituent, and the group may further have a second substituent. When the alkyl group, etc. of R ¹¹ and R ¹² has the above-mentioned third substituent, the number of carbon atoms in R ¹¹ and R ¹² is 1 to 20 including the number of carbon atoms in the third substituent. It is preferable. In the case where the third substituent further has a third substituent or the above group further has a third substituent, the number of carbon atoms of R ¹¹ and R ¹² including the plurality of third substituents is It is preferable that the number of carbon atoms is 1 to 20. When R ¹¹ and R ¹² have a third substituent, and the third substituent further has a third substituent, R ¹¹ and R ¹² include, for example, a group having a glycol chain or a thioglycol chain. can be mentioned.

R ¹³ and R ¹⁴ each independently represent an alkyl group, a hydroxy group, a mercapto group, an alkyleneoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkyleneoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, or an arylsulfanyl group. group, alkylsulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, (meth)acryloyloxy group, hydroxy(poly)alkyleneoxy group, amino group , a cyano group, a nitro group, and a halogen atom, the number of carbon atoms is 1 to 12, and these are substituents (hereinafter referred to as "fourth substituents"). (also referred to as "group").

One R ¹⁴ forms a ring structure with an aryl group to which the R ¹⁴ is bonded via any one selected from the group consisting of a direct bond, a methylene group, an oxygen atom, a sulfur atom, and a divalent nitrogen atom-containing group. It may be formed.

Examples of the fourth substituent in R ¹³ and R ¹⁴ include the same as the above-mentioned fourth substituent.

When the alkyl group of R ¹³ and R ¹⁴ has the above-mentioned fourth substituent, the number of carbon atoms of R ¹³ and R ¹⁴ is 1 to 20 including the number of carbon atoms of the fourth substituent. It is preferable.

When the alkyl group R ¹³ and R ¹⁴ is present, at least one methylene group of the alkyl group may be substituted with the divalent heteroatom-containing group. However, it is preferable not to have a continuous chain of hetero atoms such as -OO-, -SS-, and -OS-. Examples of R ¹³ and R ¹⁴ in which at least one of the methylene groups may be substituted with the divalent heteroatom-containing group include 2-methoxyethoxy group, 2-ethoxyethoxy group, 2-(2-methoxy Polyalkyleneoxy groups such as ethoxy) ethoxy, 2-(2-ethoxyethoxy)ethoxy, 2-methoxypropoxy and 3-methoxypropoxy; polyalkyleneoxy such as 2-methylthioethylthio and 2-ethylthioethylthio Examples include alkylenethio groups; and polyalkyleneoxythio groups such as 2-methylthioethoxy and 2-ethoxyethylthio groups. However, some aspects of the invention are not so limited.

Preferred examples of ^R14 include an arylsulfanyl group, an alkylsulfanyl group, an amino group having the above-mentioned fourth substituent, a hydroxy group, an alkoxy group, etc., since absorption of the second active energy ray when it becomes a ketone derivative is preferred. is preferable from the viewpoint of acid generation efficiency.
When R ¹⁴ is an arylsulfanyl group, an alkylsulfanyl group, an amino group having the above-mentioned fourth substituent, a hydroxy group, or an alkoxy group, R ¹⁴ is at the para position with respect to the bonding position of the acetal moiety or thioacetal moiety. is preferred. When these substituents are at the para position, absorption of the second active energy rays tends to increase when a ketone derivative is formed.

R ¹⁵ and R ¹⁶ each independently represent a straight chain, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; a straight chain which may have a substituent; Branched or cyclic alkenyl groups having 2 to 12 carbon atoms; aryl groups having 6 to 14 carbon atoms which may have a substituent; and aryl groups having 4 to 12 carbon atoms which may have a substituent. It is preferably selected from the group consisting of: heteroaryl group;
The above R ¹⁵ and R ¹⁶ may be bonded to each other to form a ring structure directly with a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group,
At least one methylene group in R ¹⁵ and R ¹⁶ may be substituted with the divalent heteroatom-containing group.

Examples of the substituents for R ¹⁵ and R ¹⁶ include those similar to the third substituent described above.

L ² is a direct bond; a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms; an alkenylene group having 2 to 12 carbon atoms; an arylene group having 6 to 14 carbon atoms; It is preferably selected from the group consisting of a heteroarylene group; and a group in which these groups are bonded via an oxygen atom, a sulfur atom, or the above divalent nitrogen atom-containing group.

L ³ is preferably selected from the group consisting of a direct bond, a methylene group, a sulfur atom, the above divalent nitrogen atom-containing group, and an oxygen atom.

Y is an oxygen atom or a sulfur atom.
h is an integer from 1 to 2, and i is an integer from 1 to 3.
j is an integer from 0 to 3 when h is 1 and from 0 to 5 when h is 2.
k is an integer from 0 to 4 when i is 1, from 0 to 6 when i is 2, and from 0 to 8 when i is 3.

In one embodiment of the present invention, the onium salt structure in unit A is preferably a monocation. Even when h in the above general formula (3) and the above general formula (4) is 1 to 2, the sulfonium cation is preferably a monocation. L ² in the above general formula (3) is replaced with any one hydrogen atom on the arylene shown by the arrows in the following general formulas (3-a) to (3-b), when h is 1 to 2. . Similarly, for L ² in the above general formula (4), when h is 1 to 2, any one hydrogen atom on the arylene shown by the arrows in the following general formulas (4-a) to (4-b) Replaced with

Any one hydrogen among R ¹¹ , R ¹² and R ¹⁴ and the hydrogen atom on the aryl ring to which R ¹⁴ is bonded are replaced by a bond with Sp in the above formula (1).
In the above formula (4), R ¹¹ to R ¹⁶ , L ² and Y are each independently selected from the same choices as each of R ¹¹ to R ¹⁶ , L ² and Y in the above formula (3).
h is an integer from 1 to 2, and i is an integer from 1 to 3.
j is an integer from 0 to 4 when h is 1, and from 0 to 6 when h is 2.
k is an integer from 0 to 5 when i is 1, from 0 to 7 when i is 2, and from 0 to 9 when i is 3.
L ⁴ and L ⁵ are each independently selected from the group consisting of a direct bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, and a carbonyl group.

In one embodiment of the present invention, the cation (M ⁺ ) having an onium salt structure contained in unit A can be exemplified by those having a sulfonium cation shown below. The wavy line in the sulfonium cation shown below indicates a bonding site with Sp in the above formula (1), and when there are multiple wavy lines in the same structure, it is preferable that one of them bond with the Sp. However, some aspects of the invention are not so limited.

The anion of unit A is not particularly limited as long as it is an f-valent anion, but from the viewpoint of improving the development contrast in photoresist pattern formation, specific examples include tetrafluorosuccinate dianion, hexafluoroglutarate dianion, octafluoroglutarate dianion, and octafluoroglutarate dianion. Examples include adipic acid dianion, 2,2-difluoro(2-oxysulfonyl)acetic acid dianion, L-cysteinic acid dianion, oxaloacetic acid dianion, sulfosuccinic acid dianion, sulfosuccinic acid trianion, and citrate trianion.

One embodiment of the present invention may include two or more types of units A in the polymer. For example, it is also preferable to use one as the photoacid generator unit A and the other as the photodegradable base unit A. It is preferable that the photo-degradable base unit A has a lower acid strength than the photo-acid generator unit A and is used in combination with the photo-acid generator unit A.
Furthermore, when the polymer has two or more types of units A, units having the same onium salt structure but different substituents such as R ¹ and L may be used.

The onium salt structure containing unit A according to one embodiment of the present invention preferably has a molar extinction coefficient of less than 1.0×10 ⁵ cm ² /mol at 365 nm, and preferably less than 1.0×10 ⁴ cm ² /mol. More preferably, it is less than mol.
Further, when the onium salt structure contained in unit A according to some aspects of the present invention has an acetal moiety or a thioacetal moiety, the ketone derivative from which the acetal moiety or thioacetal moiety is deprotected has a molar extinction coefficient of 365 nm. is preferably 1.0×10 ⁵ cm ² /mol or more, more preferably 1.0×10 ⁶ cm ² /mol or more.
The molar extinction coefficient at 365 nm of the ketone derivative is preferably 5 times or more, and preferably 10 times or more, the molar extinction coefficient at 365 nm of the onium salt structure contained in unit A according to one embodiment of the present invention. More preferably, it is 20 times or more.
In order to obtain the above characteristics, an onium salt having a cation represented by the above formula (3) or (4) may be used.

(Unit B)
The polymer in one embodiment of the present invention further contains an organometallic compound-containing unit (hereinafter also referred to as "unit B") having a metal atom selected from the group consisting of Sn, Sb, Ge, Bi, and Te. .
The metal atoms contained in the unit B are not particularly limited as long as they have high absorption for EUV or electron beams, and may be atoms from groups 10 to 16 of the periodic table in addition to the metal atoms mentioned above. good.
The above unit B is a unit in which an alkyl and aryl tin, an alkyl and aryl antimony, an alkyl and aryl germane, or an alkyl and arylbismuthine structure is bonded to the * part of the following formula (5) at any position of the structure. It is preferable. Equation (5) will be explained in the unit C section below.
Unit B has high secondary electron generation efficiency through EUV irradiation and can increase the decomposition efficiency of unit A. Unit B is not particularly limited as long as it contains the metal atom with high EUV absorption, but specific examples include the units shown below.

In the above general formula, each R ^12a is preferably independently selected from the group consisting of a hydrogen atom and an alkyl group. The alkyl group as R ^12a may have a substituent.
The above-mentioned alkyl group is a linear or branched one having 1 to 5 carbon atoms such as methyl group, ethyl group, isopropyl group, n-isopropyl group, sec-butyl group, tert-butyl group, n-butyl group, pentyl group, etc. Examples include alkyl groups of the form.
Examples of substituents that the alkyl group may have include a hydroxy group, a sulfonyloxy group, an alkylcarbonyloxy group, an alkyloxycarbonyl group, a cyano group, a methoxy group, and an ethoxy group.
In the above formula, when two or more R ^12a are not hydrogen atoms, the two R ^12a which are not hydrogen atoms are directly connected by a single ^bond , or are connected to an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, or A ring structure may be formed via any one selected from the group consisting of methylene groups.
In the above formula, two R ^12b form a ring structure directly through a single bond or through any one selected from the group consisting of an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and a methylene group. You may.
n ⁹ is an integer from 0 to 4.

In the above general formula, R ^12b is a straight chain, branched or cyclic alkyl group having 1 to 6 carbon atoms which may have a substituent; An alkenyl group having 2 to 6 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; a heteroaryl group having 4 to 12 carbon atoms which may have a substituent; and a direct bond; Any one selected from the group consisting of.
Examples of the straight chain, branched or cyclic alkyl group for R ^12b include the same alkyl groups as for R ^2b above.
Examples of the linear, branched or cyclic alkenyl group for R ^12b include the same alkenyl groups as for R ^2b above.

Examples of the aryl group having 6 to 14 carbon atoms for R ^12b include the same aryl groups as for R ^2b above. Examples of the heteroaryl group having 4 to 12 carbon atoms for R ^12b include those similar to the heteroaryl group for R ^2b above.
Two or more R ^12a form a ring structure directly through a single bond or through any one selected from the group consisting of an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and a methylene group. Good too. Further, any two of the three R ^12b may be bonded to each other to form a ring structure together with the metal atom to which they are bonded.
Examples of the substituents that R ^12a and R ^12b may have include the same substituents as the first substituent that Sp has.

Preferred examples of the unit B include those in the following formula (5) in which R ¹ is a hydrogen atom or a linear alkyl group, and is an L carbonyloxy group or a phenylenediyl group.
In addition, as unit B, L is a carbonyloxy group or a carbonylamino group, Sp is a direct bond, R ¹ is a methyl group, and the methyl group has the number of carbon atoms among the first substituents. A unit having at least one of a 1-4 alkyl group, a halogen atom, and an aryl group is preferable from the viewpoint of LWR. Particularly preferable examples of R ¹ having the first substituent include ethyl group, isopropyl group, butyl group, halogenated methyl group (fluoromethyl group, chloromethyl group, bromomethyl group, iodomethyl group, etc.), and benzyl group. Can be mentioned.

Specifically, Unit B includes 4-vinylphenyl-triphenyltin, 4-vinylphenyl-tributyltin, 4-isopropenylphenyl-triphenyltin, 4-isopropenylphenyl-trimethyltin, trimethyltin acrylate, and acrylic acid. Tributyltin, triphenyltin acrylate, trimethyltin methacrylate, tributyltin methacrylate, triphenyltin methacrylate, 4-vinylphenyl-diphenylantimony, 4-isopropenylphenyl-diphenylantimony, 4-vinylphenyl-triphenylgermane, 4 -vinylphenyl-tributylgermane, 4-isopropenylphenyl-triphenylgermane, and 4-isopropenylphenyl-trimethylgermane.
When the polymer contains the unit B, it is possible to improve the efficiency of secondary electron generation when irradiated with particle beams or electromagnetic waves.
One embodiment of the present invention may include two or more types of units B in the polymer.

(Unit C)
The polymer of one embodiment of the present invention further has a unit C, and the unit C is a compound represented by the following general formula (I) or (II) at any position of the compound represented by the following formula (5). Preferably, it is a unit bonded to an Sp group.

The above unit C is preferably a unit in which a compound represented by the above general formula (I) or (II) is bonded to an Sp group of the following formula (5) at any position of the compound.
In the polymer containing the unit C, the hydroxyl group is removed by the action of the acid generated by the decomposition of the unit A, thereby improving hydrophobicity and making it possible to improve the development contrast.

In the above formula (5), R ¹ , L and Sp are the same as R ¹ , L and Sp in the above general formula (1).

In the above general formula (I), R ² and R ³ are each independently selected from the group consisting of a hydrogen atom; an electron-donating group; and an electron-withdrawing group. It is preferable that at least one of R ² and R ³ be the above-mentioned electron-donating group because acid reactivity is improved.
E is preferably one selected from the group consisting of a direct bond; an oxygen atom; a sulfur atom; and a methylene group.
R ⁴ is any one selected from the group consisting of a hydrogen atom; an alkyl group that may have a substituent; and an alkenyl group that may have a substituent. Examples of the alkyl group and alkenyl group in R ⁴ include the same ones as in R ¹ .
By having hydrogen at the β position of the hydroxyl group, a dehydration reaction occurs efficiently within the molecule by the action of an acid, improving hydrophobicity and improving the development contrast. Therefore, R ⁴ is a primary alkyl group, a secondary alkyl group, etc. Preferable examples include a primary alkenyl group, a primary alkenyl group, and a secondary alkenyl group.

It is preferable that n ¹ is an integer of 0 or 1. n ⁴ and n ⁵ are each integers of 1 to 2. It is preferable that n ⁴ +n ⁵ is 2-4.
When n ⁴ is 1, n ² is preferably an integer of 0 to 4. When n ⁴ is 2, n ² is preferably an integer of 0 to 6.
When n ⁵ is 1, n ³ is preferably an integer of 0 to 4. When n ⁵ is 2, n ³ is preferably an integer from 0 to 6.
When n ² is 2 or more and R ² is an electron-donating group or an electron-withdrawing group, the two R ^2s are directly connected by a single bond, or an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and A ring structure may be formed with each other via any one selected from the group consisting of methylene groups.
When n ³ is 2 or more and R ³ is an electron-donating group or an electron-withdrawing group, two R ^3s are directly connected to each other by a single bond, or an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and A ring structure may be formed with each other via any one selected from the group consisting of methylene groups.
Examples of the divalent nitrogen atom-containing group for forming a ring structure in the above formula (I) include those similar to the divalent nitrogen atom-containing group in R ^6a above.

In the above general formula (II), R ⁶ is each independently selected from the group consisting of a hydrogen atom; an electron-donating group; and an electron-withdrawing group. It is preferable that at least one of R ⁶ be the electron-donating group, since acid reactivity is improved.
R ⁵ is any one selected from the group consisting of a hydrogen atom; an alkyl group that may have a substituent; and an alkenyl group that may have a substituent; and at least one of the above R ⁵ The methylene group may be substituted with a divalent heteroatom-containing group.
Further, R ⁵ may form a ring structure together with a benzene ring to which a hydroxymethylene group having R ⁵ is bonded.

The alkyl group for ^R5 may be a straight-chain, branched or cyclic alkyl group having a carbon number of 1 to 12. Specific examples include the same alkyl groups as those for ^R6b .
Examples of the substituent that R ⁵ has include the same ones as the first substituent that Sp has.

Preferably, n ⁶ is an integer from 0 to 7. It is preferable that ⁿ⁷ is 1 or 2. When ⁿ⁷ is 1, n6 is preferably an integer from 0 to 5. When n ⁷ is 2, n ⁶ is preferably an integer from 0 to 7.

When n ⁶ is 2 or more and R ⁴ is an electron-donating group or an electron-withdrawing group, two R ^4s are directly connected to each other by a single bond, or an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and A ring structure may be formed with each other via any one selected from the group consisting of methylene groups.
Examples of the divalent nitrogen atom-containing group for forming a ring structure in the above formula (II) include those similar to the divalent nitrogen atom-containing group in R ^6a above.

Examples of the electron-donating group for R ² , R ³ , and R ⁶ include an alkyl group (-R ^a ), an alkenyl group in which at least one carbon-carbon single bond of the alkyl group (-R ^a ) is replaced with a carbon-carbon double bond; and an alkoxy group (-OR ^a ) and an alkylthio group (-SR ^a ) bonded at the ortho- or para-position relative to the position of the aromatic ring to which the methine carbon to which the hydroxyl group is bonded is bonded.

The above R ^a is preferably an alkyl group having 1 or more carbon atoms. Specific examples of alkyl groups having one or more carbon atoms include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-octyl group, and n-decyl group. Linear alkyl groups such as isopropyl group, isobutyl group, tert-butyl group, isopentyl group, tert-pentyl group, branched alkyl group such as 2-ethylexyl group; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group , adamantane-1-yl group, adamantane-2-yl group, norbornan-1-yl group and norbornan-2-yl group; one of these hydrogens is trimethylsilyl group, triethylsilyl group and dimethyl A silyl group-substituted alkyl group substituted with a trialkylsilyl group such as an ethylsilyl group; in the above alkyl group, the hydrogen atom of a carbon atom that is not directly bonded to the aromatic ring of the above compound (I) or (II) Preferred examples include an alkyl group, at least one of which is substituted with a cyano group or a fluoro group. The number of carbon atoms in R ^a is preferably 4 or less.

Examples of the electron-withdrawing group for R ² , R ³ and R ⁶ include -C(═O)R ^17a (R ^17a is a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent); -C(═O)R ^17b (R ^17b is an aryl group having 6 to 14 carbon atoms which may have a substituent); -C(═O)OR ^17a ; -SO ₂ R ^17a ; -SO ₂ R ^17b ; a nitro group; a nitroso group, a trifluoromethyl group, -OR ^17a substituted at the meta position relative to a hydroxyl group; -OR 17b substituted at the meta position relative to a hydroxyl group; -SR ^17a substituted at the meta position relative to a hydroxyl group; -SR ^17b substituted at the meta position relative to a hydroxyl group; and the above-mentioned -C(═O)R ^17a , -C(═O)OR ^{17a ,} -SO ₂ a group in which at least one of the carbon-carbon single bonds in R ^17a and -SR ^17a is replaced with a carbon-carbon double bond or a group in which at least one of the carbon-carbon single bonds is replaced with a carbon-carbon triple bond; and the like.
Examples of the substituent that may be possessed by R ^17a and R ^17b include the same as the first substituent possessed by the above Sp.

The substituents in R ⁴ and R ⁵ in the above general formula (I) or (II) include the same substituents as the above first substituent.
Note that, when each of R ² , R ³ , R ⁴ , R ⁵ and R ⁶ has a substituent, it is preferable that the number of carbon atoms including the substituent is 1 to 14.

Examples of the compound represented by the above general formula (I) or (II) include those shown below.

One embodiment of the polymer of the present invention is a unit in which any of the compounds represented by the above general formula (I) or (II) is bonded to the * part of the above formula (5) at any position of the compound. This is an embodiment in which C is included in the polymer. In that case, any one of R ² , R ³ and R ⁶ is preferable for the position bonded to the * portion of the above formula (5). For example, in the case of the compound represented by the above general formula (I), it is preferable to have a bond that is bonded to the * portion of the above formula (5) in place of one H in R ² .

Preferably, the above unit C includes those in the above formula (5) in which R ¹ is a hydrogen atom or a linear alkyl group, and is an L carbonyloxy group, a carbonylamino group, or a phenylenediyl group.
Further, as the unit C, L is a carbonyloxy group or a carbonylamino group, Sp is a direct bond, R ¹ is a methyl group, and the methyl group is a carbon A unit having at least one of several alkyl groups, halogen atoms, and aryl groups is preferable from the viewpoint of LWR. Particularly preferable examples of R ¹ having the first substituent include ethyl group, isopropyl group, butyl group, halogenated methyl group (fluoromethyl group, chloromethyl group, bromomethyl group, iodomethyl group, etc.), and benzyl group. Can be mentioned.
In one embodiment of the present invention, the polymer may contain two or more types of units C.

(Unit D)
The resist composition in one embodiment of the present invention is characterized in that an intramolecular crosslinking reaction occurs upon irradiation with particle beams or electromagnetic waves. Therefore, a unit D having an onium salt structure other than the unit A may be included.
The unit D may be a unit represented by the following formula (6).

In the above general formula (6), R ¹ , L, Sp, and M ⁺ are selected from the same options as R ¹ , L, Sp, and M ⁺ described in the above general formula (1), and Z ⁻ is a monovalent anion.

Z ^- includes alkyl sulfate anion, aryl sulfate anion, alkyl sulfonate anion, arylsulfonate anion, alkyl carboxylate anion, aryl carboxylate anion, tetrafluoroborate anion, hexafluorophosphonate anion, dialkyl sulfonylimide anion, trialkyl Any one selected from the group consisting of sulfonate methide anion, tetrakis phenylborate anion, hexafluoroantimonate anion, monovalent metal oxonium anion, and hydroxide anion containing these can be mentioned. Furthermore, at least one hydrogen atom of the alkyl group or aryl group in Z ^- may be substituted with a fluorine atom. Furthermore, at least the methylene group in the alkyl group in Z ^- may be substituted with the above-mentioned divalent heteroatom-containing group. The total number of carbon atoms in the above Z ^- is preferably 0 to 20, more preferably 0 to 10.
Examples of metal oxonium anions include NiO ₂ ^- and SbO ₃ ^- . _In ^{addition ,} _{2- ​} ^​ _​ ^​ _​ ^​ _​ ^​ _​ ^​ _​ ^​ _​ ^​ The valence may be made monovalent by appropriately adding H ⁺ , sulfonium ions, iodonium ions, monovalent to divalent metal cations, etc. to trivalent compounds. The above-mentioned mono- or divalent metal cations may be ordinary ones, such as Na+, Sn ²⁺ , Ni ²⁺ , and the like.

One embodiment of the present invention may include two or more types of the units D in the polymer.

When the polymer in one embodiment of the present invention further has unit D, the crosslinking density due to unit A can be adjusted, and the polymer further has unit D, which has an effect of excellent solubility in the resist composition.

(Other units)
In one embodiment of the present invention, the polymer may have the following units E to K in addition to the above units A to D.
Unit E: A unit having an aryloxy group in the * part of the above formula (5) Unit F: A unit having a radical generating structure containing at least one multiple bond in the * part of the above formula (5) Unit G: The above formula ( Unit H having a structure containing a halogen atom in the * part of 5): Contains an ether group, lactone skeleton, ester group, hydroxy group, epoxy group, glycidyl group, oxetanyl group, etc. in the * part of the above formula (5) Unit having a skeleton Unit I: A unit having a skeleton having an alcoholic hydroxyl group in the * part of the above formula (5) Unit J: A straight chain, branched or cyclic carbon number 1 to 6 in the * part of the above formula (5) and a unit having a linear, branched or cyclic alkenyl group having 2 to 6 carbon atoms Unit K: a unit having a structure containing a silicon atom in the * part of the above formula (5)

The units E to K are different from the units A to D, and the units E to K are different from each other. Specifically, each of the units E to K includes the units disclosed in WO2022/39212.

(polymer)
In one embodiment of the present invention, the polymer preferably has a molar ratio of the unit B to the unit A of 0.2 to 5, and preferably has a molar ratio of the unit C of 0 to 3. The unit D is preferably 0 to 20, more preferably 1 to 10, and even more preferably 2 to 5. It is preferable that each of the other units E to K is 0 to 2.

The above unit A preferably accounts for 5 to 50 mol%, more preferably 10 to 20 mol% of the total units of the polymer. The amount of the unit B is preferably 10 to 90 mol%, more preferably 30 to 50 mol%. The amount of the unit D is preferably 10 to 50 mol%, more preferably 20 to 40 mol%.
The polymer in one embodiment of the present invention can be obtained by polymerizing the monomer components constituting each of the above units as raw materials in a conventional manner so as to achieve the above blending ratio. Further, in one embodiment of the present invention, a polymer containing a unit having an onium salt structure having a monovalent anion (referred to as a "precursor polymer") is first synthesized, and in the precursor polymer, an f-valent anion It may be a polymer containing the above unit A in which the monovalent anion of the onium salt structure is salt-exchanged using a salt having the above-mentioned onium salt structure to the desired f-valent anion. In the salt exchange, all monovalent anions may be salt-exchanged to become f-valent anions, or some monovalent anions may be left. By performing salt exchange so that some monovalent anions remain, a polymer containing a unit D having an onium salt structure other than the unit A can be obtained.

<2> Resist Composition A resist composition according to one embodiment of the present invention is characterized by containing the above polymer. In addition to the above polymers, components such as organometallic compounds and organometallic complexes may be optionally contained. Each component will be explained below.
The resist composition of one embodiment of the present invention may contain other components as long as the effects of the present invention are not impaired. Ingredients that can be blended include known additives, such as fluorine-containing water-repellent polymers, quenchers such as trioctylamine, surfactants, fillers, pigments, antistatic agents, flame retardants, light stabilizers, and oxidants. At least one selected from inhibitors, ion scavengers, solvents, etc. can be mentioned.

<3> Method for preparing resist composition The method for preparing the resist composition of one embodiment of the present invention is not particularly limited, and may be prepared by a known method such as mixing, dissolving, or kneading the above polymer and other optional components. be able to.
The above polymer can be synthesized by suitably polymerizing the monomers constituting the above units A and B, and, if necessary, the monomers constituting other units, by a conventional method. However, the method for producing a polymer according to the present invention is not limited to this.

<4> Method for manufacturing member One embodiment of the present invention includes a resist film forming step of forming a resist film on a substrate using the resist composition, and forming the resist film into a pattern using particle beams or electromagnetic waves. This method of manufacturing a member includes a photolithography step of exposing the resist film to light, and a pattern forming step of developing the exposed resist film using a developer to dissolve the exposed area and obtain a photoresist pattern.
Examples of the above-mentioned members include devices, masks, and the like.

Examples of particle beams and electromagnetic waves used for exposure in the photolithography process include electron beams and EUV, respectively.
The amount of light irradiation varies depending on the type and blending ratio of each component in the photocurable composition, the thickness of the coating film, etc., but is preferably 1 J/cm ² or less or 1000 μC/cm ² or less.
The above resist composition, when the above M ⁺ includes one of the above formulas (3) or (4) as the unit A in the polymer, has an energy lower than that of the particle beam or electromagnetic wave after irradiation with the particle beam or electromagnetic wave. It is also preferable to further irradiate with a second active energy ray. Examples of the second active energy ray include ultraviolet rays. Sensitivity is improved by further irradiating the second active energy ray.

Further, one aspect of the present invention includes a resist film forming step of forming a resist film on a substrate using the resist composition, and a photolithography step of exposing the resist film using a particle beam or an electromagnetic beam. , a pattern forming step of developing the exposed resist film using a developer to dissolve exposed areas and obtain a photoresist pattern.

It is preferable to use an organic solvent for development in the pattern forming step.
As described above, in the polymer of one embodiment of the present invention, upon exposure to particle beams or electromagnetic radiation, the unit A decomposes and a large polarity change from ionic to nonionic occurs. At the same time, due to the decomposition of the unit A, the f-valent anion is protonated to generate an acid. As a result, the polymer formed via the anion is decomposed and the crosslinked structure between polymer molecules is eliminated, thereby changing the solubility of the polymer. Therefore, in a resist composition containing the above polymer, the solubility can be greatly changed by the decomposition of the polymer in addition to the polarity conversion caused by the decomposition of the unit A, so even without using acid diffusion, the resist composition has high sensitivity. Positive patterning can be obtained by dissolving the exposed areas while maintaining high development contrast using an organic solvent as a developer.

The organic solvent used as a developer for obtaining a positive patterning can be appropriately selected from known organic solvents used as organic solvent developers, such as ketone-based solvents, ester-based solvents, nitrile-based solvents, alcohol-based solvents, and ether-based solvents.
Examples of the ketone solvent include acetone, 2-heptanone, 2-hexanone, cyclohexanone, acetophenone, methyl ethyl ketone, diisobutyl ketone, and diacetone alcohol.
Examples of the ester solvent include methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, amyl acetate, hexyl acetate, propylene glycol monomethyl ether acetate (PGMEA), and ethylene glycol monoethyl ether acetate.
Examples of the nitrile solvent include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

Examples of alcohol-based solvents include alcohols such as ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, n-hexyl alcohol, and n-heptyl alcohol; glycols such as ethylene glycol, propylene glycol, and diethylene glycol. Solvents include glycol ether solvents such as ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monoethyl ether, and methoxymethyl butanol.
Examples of ether solvents include di-n-propyl ether, di-n-butyl ether, dioxane, tetrahydrofuran, and the like, in addition to the glycol ether solvents mentioned above.

Among organic solvents, there are organic solvents that contain multiple types of functional groups that characterize each of the above solvents in their structure, but in that case, any solvent type that contains the functional groups that the organic solvent has shall be taken as a thing. For example, diethylene glycol monomethyl ether falls under both alcohol solvents and ether solvents in the above classification.

The developer in the present invention is preferably prepared and used as appropriate depending on the composition of the resist composition containing the above polymer. The developer may be a combination of two or more of the above organic solvents.
As the developing solution in the method for manufacturing a member according to one embodiment of the present invention, an organic solvent suitable for the resist composition according to one embodiment of the present invention can be appropriately selected and used. Although there are no particular restrictions on the selection of the developer, it is preferable to select it as follows, for example.
(1) Using a resist composition sample in which the above polymer is dissolved in a solvent in which ethyl lactate and γ-butyrolactone are mixed at a ratio of 9:1, a film is prepared by applying the composition to a predetermined thickness. .
(2) Prepare various organic solvents as a developer.
(3) Each film obtained in (1) above is impregnated with various organic solvents. After that, it is dried and the film thickness is measured.
(4) Based on the film thickness measurement obtained in (3) above, an organic solvent that provides a desired residual film ratio is selected as a developer for the resist composition sample.

In the present invention, butyl acetate, amyl acetate, hexyl acetate, 2-heptanone, propylene glycol monomethyl ether acetate (PGMEA), etc. are preferred.

Hereinafter, some aspects of the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way.

Compounds A1 to A5, B1 to B2, B5, and C1 to C2 below were synthesized with reference to the examples in WO2022/039212. Compounds B3 to B4 below were synthesized with reference to the examples in JP2023-122060A.

<Synthesis of compound A6 constituting unit A>
(Synthesis Example 1) Synthesis of 4-hydroxyphenyl-2-[dipropioxy-(4-methoxyphenyl)methyl]dibenzothiophenium-methylsulfate 4-hydroxyphenyl-2-[dimethoxy-(4-methoxyphenyl)methyl] Add 2.5 g of dibenzothiophenium-methyl sulfate to 20 g of 1-propanol, add 5.0 g of trimethyl orthoformate and 20 mg of concentrated sulfuric acid, and stir at 60° C. for 3 hours. After stirring, the reaction solution is added to a mixed solution of 60 g of methylene chloride and 10 g of a 3% by mass aqueous sodium bicarbonate solution, stirred for 10 minutes, and the organic layer is collected. After washing the obtained organic layer three times with water, methylene chloride is distilled off to obtain 2.0 g of 4-hydroxyphenyl-2-[dipropioxy-(4-methoxyphenyl)methyl]dibenzothiophenium-methyl sulfate. . Note that 4-hydroxyphenyl-2-[dimethoxy-(4-methoxyphenyl)methyl]dibenzothiophenium-methylsulfate was synthesized with reference to WO2022/039212.

(Synthesis Example 2) Synthesis of 4-methacroxyphenyl-2-[dipropioxy-(4-methoxyphenyl)methyl]dibenzothiophenium-methylsulfate (Compound A6) 4-Hydroxyphenyl-2 obtained in Synthesis Example 1 above - 4.0 g of [dipropioxy-(4-methoxyphenyl)methyl]dibenzothiophenium-methyl sulfate and 1.9 g of methacrylic acid chloride are dissolved in 25 g of methylene chloride and brought to 25°C. A solution of 1.4 g of triethylamine dissolved in 7 g of methylene chloride was added dropwise to this, and the mixture was stirred at 25° C. for 2 hours. After stirring, 20 g of pure water was added and the mixture was further stirred for 10 minutes, followed by liquid separation. After washing the organic layer twice with 20 g of pure water, the collected organic layer is concentrated and added dropwise to 60 g of diisopropyl ether to precipitate a solid. The precipitated solid is filtered and dried to obtain 3.8 g of 4-methacroxyphenyl-2-[dipropioxy-(4-methoxyphenyl)methyl]dibenzothiophenium-methyl sulfate (Compound A6).

(Synthesis Example 3) Synthesis of 4-hydroxyphenyl-2-[1,3-dioxepan-2-yl-(4-methoxyphenyl)methyl]dibenzothiophenium-methyl sulfate 4-hydroxyphenyl-2-[dimethoxy- (4-methoxyphenyl)methyl]dibenzothiophenium-methylsulfate was replaced with 4-hydroxyphenyl-2-[dimethoxy-(4-methoxyphenyl)methyl]dibenzothiophenium-methylsulfate, and methanol was added to , 4-Butanediol was used in the same manner as in Synthesis Example 1 to obtain 4-hydroxyphenyl-2-[1,3-dioxepan-2-yl-(4-methoxyphenyl)methyl]dibenzothiophene. Obtain 2.0 g of Ni-methyl sulfate. Note that 4-hydroxyphenyl-2-[dimethoxy-(4-methoxyphenyl)methyl]dibenzothiophenium-methylsulfate was synthesized with reference to WO2022/039212.

<Synthesis of compound A7 constituting unit A>
(Synthesis Example 4) Synthesis of 4-methacroxyphenyl-2-[1,3-dioxepan-2-yl-(4-methoxyphenyl)methyl]dibenzothiophenium-methylsulfate (compound A7) 9-(4- 4-hydroxyphenyl-2-[1,3-dioxepan-2-yl-(4-methoxyphenyl)methyl]dibenzothiophenium obtained in Synthesis Example 3 above in place of hydroxyphenyl)dibenzothiophenium-methyl sulfate - By performing the same operation as in Synthesis Example 2 above except for using methyl sulfate, 4-methacryoxyphenyl-2-[1,3-dioxepan-2-yl-(4-methoxyphenyl)methyl]dibenzothiophene 3.8 g of nium-methyl sulfate (compound A7) are obtained.

<Synthesis of compound A8 constituting unit A>
(Synthesis Example 5) Synthesis of {4-[dimethoxy-(4-methacroxyphenyl)methyl]phenyl}diphenylsulfonium-methylsulfate (compound A8) Instead of 9-(4-hydroxyphenyl)dibenzothiophenium-iodide 3.0 g of {4-[dimethoxy-(4-methacryoxyphenyl)methyl]phenyl}diphenylsulfonium-iodide and 2.3 g of dimethyl sulfuric acid are dissolved in 15 g of methanol and stirred at 25° C. for 4 hours at room temperature. Thereafter, 45 g of diisopropyl ether is added to precipitate a solid. The precipitated solid is filtered and dried to obtain 2.3 g of {4-[dimethoxy-(4-methacryoxyphenyl)methyl]phenyl}diphenylsulfonium-methylsulfate (compound A8). In addition, {4-[dimethoxy-(4-methacryoxyphenyl)methyl]phenyl}diphenylsulfonium-iodide was synthesized with reference to the example in JP-A No. 2023-122060.

<Synthesis of compound A9 constituting unit A>
(Synthesis Example 6) Synthesis of (4-{dimethoxy-[4-(3-methacroxypropyl-1-oxy)phenyl]methyl}phenyl)diphenylsulfonium-methylsulfate (compound A9) 9-(4-hydroxyphenyl) Same as Synthesis Example 5 above except that (4-{dimethoxy-[4-(3-methacryoxypropyl-1-oxy)phenyl]methyl}phenyl)diphenylsulfonium-iodide is used instead of dibenzothiophenium-iodide. By carrying out the operation, 2.3 g of (4-{dimethoxy-[4-(3-methacroxypropyl-1-oxy)phenyl]methyl}phenyl)diphenylsulfonium-methylsulfate (compound A9) are obtained. Note that (4-{dimethoxy-[4-(3-methacryoxypropyl-1-oxy)phenyl]methyl}phenyl)diphenylsulfonium-iodide was synthesized with reference to JP-A-2023-122060.

<Synthesis of compound C3 constituting unit C>
(Synthesis Example 7) Synthesis of 4-hydroxy-4'-methoxy-α-methylbenzhydrol 6.0 g of 4-hydroxy-4'-methoxybenzophenone was dissolved in 32 g of THF, and dissolved in 2.0 M methylmagnesium bromide/THF. Add 39 ml of solution and stir at room temperature for 3 hours. Thereafter, the mixture is cooled to 10° C. or lower, 6 g of pure water is added, and the mixture is further stirred for 10 minutes. After stirring, 30 g of ethyl acetate is added and the mixture is separated. This was washed three times with 10 g of water, and the collected organic layer was concentrated to obtain 5.1 g of 4-hydroxy-4'-methoxy-α-methylbenzhydrol.

(Synthesis Example 8) Synthesis of 4-methacryloxy-4'-methoxy-α-methylbenzhydrol (Compound C3) 4-Hydroxy-4'-methoxy-α-methylbenzhydrol 4 obtained in Synthesis Example 7 above .0 g and 4.2 g of methacrylic anhydride were dissolved in 40 g of methylene chloride and brought to 25°C. A solution of 2.8 g of triethylamine dissolved in 7 g of methylene chloride was added dropwise to this, and the mixture was stirred at 25° C. for 2 hours. After stirring, 20 g of pure water was added and the mixture was further stirred for 10 minutes, followed by liquid separation. After washing the organic layer twice with 20 g of pure water, the collected organic layer was concentrated, and the solvent was distilled off from the obtained organic layer, and then purified by column chromatography (ethyl acetate/hexane = 15/85 (volume ratio)). By doing so, 3.1 g of 4-methacryloxy-4'-methoxy-α-methylbenzhydrol (compound C3) was obtained.

<Polymer synthesis>
(Synthesis Example 9) Synthesis of Polymer 1 3.0 g of the above compound A1 constituting unit A, 2.0 g of the above compound B1 constituting unit B, and dimethyl-2,2'-azobis( 0.71 g of 2-methylpropionate) and 0.15 g of α-thioglycerol are dissolved in a mixed solution of 9 g of cyclohexanone and 13 g of γ-butyrolactone to deoxidize. This was added dropwise over 4 hours to a mixed solution of 4 g of γ-butyrolactone and 4 g of cyclohexanone that had been heated to 80° C. in advance. After the addition, the mixture was stirred for 2 hours and then cooled. After cooling, it is reprecipitated by dropping it into 90 g of ethyl acetate. After filtering this, it is stirred in 40 g of a 20% by mass methanol aqueous solution for 10 minutes, filtered, and vacuum-dried to obtain 4.5 g of the desired polymer 1.
The unit ratio of Polymer 1 below is an example, and the polymers of some embodiments of the present invention are not limited thereto. In other polymers as well, the unit ratios disclosed in the Examples are merely examples, and the polymers of some embodiments of the present invention are not limited thereto.

(Synthesis Example 10) Synthesis of Polymer 2 4.5 g of Polymer 2 was obtained in the same manner as in Synthesis Example 9, except that Compound A2 was used instead of Compound A1 constituting Unit A.

(Synthesis Example 11) Synthesis of Polymer 3 Polymer 3 was prepared in the same manner as in Synthesis Example 9, except that the compound B3 was used in place of the compound B1 constituting unit B, and the compound C1 was used as compound C1 constituting unit C. Obtain 3.1g.

(Synthesis Example 12) Synthesis of Polymer 4 Polymer 4 was prepared in the same manner as in Synthesis Example 9 above, except that the above compound A2 was used in place of the above compound A1 constituting unit A, and the above compound C3 was used as the unit C. Obtain 5.3g.

(Synthesis Example 13) Synthesis of Polymer 5 3.0 g of compound A5 constituting unit A, 2.1 g of compound B1 constituting unit B, and 1.6 g of compound C1 constituting unit C, polymerization was started. 0.71 g of dimethyl-2,2'-azobis(2-methylpropionate) and 0.15 g of α-thioglycerol were dissolved in a mixed solution of 9 g of cyclohexanone and 13 g of γ-butyrolactone to remove oxygen. do. This was added dropwise over 4 hours to a mixed solution of 4 g of γ-butyrolactone and 4 g of cyclohexanone, which had been preheated to 80°C. After the addition, the mixture is stirred for 2 hours and then cooled. After cooling, it is reprecipitated by dropping it into 90 g of ethyl acetate. After filtering this, it is stirred in 40 g of a 20% by mass methanol aqueous solution for 10 minutes, filtered, and vacuum-dried to obtain 5.3 g of the desired polymer 5.

(Synthesis Example 14) Synthesis of Polymer 6 3.0 g of compound A8 constituting unit A, 2.1 g of compound B3 constituting unit B, and 1.6 g of compound C1 constituting unit C, polymerization was started. 0.71 g of dimethyl-2,2'-azobis(2-methylpropionate) and 0.15 g of α-thioglycerol were dissolved in a mixed solution of 9 g of cyclohexanone and 13 g of γ-butyrolactone to remove oxygen. do. This was added dropwise over 4 hours to a mixed solution of 4 g of γ-butyrolactone and 4 g of cyclohexanone, which had been preheated to 80°C. After the addition, the mixture is stirred for 2 hours and then cooled. After cooling, it is reprecipitated by dropping it into 90 g of hexane. After filtering this, it is stirred in 40 g of a 20% by mass methanol aqueous solution for 10 minutes, filtered, and vacuum-dried to obtain 5.3 g of the desired polymer 6.

(Synthesis Example 15) Synthesis of Polymer 1a 2.0g of Polymer 1 obtained in Synthesis Example 9 above and 0.1g of disodium tetrafluorosuccinate were added to 25g of methylene chloride and 20g of pure water and heated at 25°C for 1 hour. Stir. Thereafter, the layers are separated, and the collected organic layer is added dropwise to ethyl acetate for reprecipitation. This is filtered and vacuum dried to obtain 1.8 g of the desired polymer 1a.

(Synthesis Example 16) Synthesis of Polymer 1b 2.0g of Polymer 1 obtained in Synthesis Example 9 above and 0.2g of disodium tetrafluorosuccinate were added to 25g of methylene chloride and 20g of pure water and heated at 25°C for 1 hour. Stir. Thereafter, the layers are separated, and the collected organic layer is added dropwise to ethyl acetate for reprecipitation. This is filtered and vacuum dried to obtain 1.2 g of the desired polymer 1b.

(Synthesis Example 17) Synthesis of Polymer 1c 2.0 g of Polymer 1 obtained in Synthesis Example 9 above and 0.066 g of trisodium citrate are added to 25 g of methylene chloride and 20 g of pure water and stirred at 25° C. for 1 hour. . Thereafter, the layers are separated, and the collected organic layer is added dropwise to ethyl acetate for reprecipitation. This is filtered and vacuum dried to obtain 1.8 g of the desired polymer 1c.

(Synthesis Example 18) Synthesis of Polymer 1d 2.0g of Polymer 1 obtained in Synthesis Example 9 above and 0.1g of disodium 1,2-ethanedisulfonate were added to 25g of methylene chloride and 20g of pure water at 25°C. Stir for 1 hour. Thereafter, the layers are separated, and the collected organic layer is added dropwise to ethyl acetate for reprecipitation. This is filtered and vacuum dried to obtain 1.8 g of the desired polymer 1d.

Synthesis Example 19: Synthesis of Polymer 1e 2.0 g of the polymer 1 obtained in Synthesis Example 9 above and 0.1 g of disodium L-cysteine acid are added to 25 g of methylene chloride and 20 g of pure water, and stirred at 25° C. for 1 hour. After that, the liquid is separated, and the recovered organic layer is dropped into ethyl acetate to reprecipitate. This is filtered and dried in vacuum to obtain 1.8 g of the target polymer 1e.

(Synthesis Example 20) Synthesis of Polymer 3a 2.0g of Polymer 3 obtained in Synthesis Example 11 above and 0.067g of disodium tetrafluorosuccinate were added to 25g of methylene chloride and 20g of pure water and heated at 25°C for 1 hour. Stir. Thereafter, the layers are separated, and the collected organic layer is added dropwise to ethyl acetate for reprecipitation. This is filtered and vacuum dried to obtain 1.8 g of the desired polymer 3a.

(Synthesis Example 21) Synthesis of Polymer 4a 2.0g of Polymer 4 obtained in Synthesis Example 12 above and 0.07g of disodium tetrafluorosuccinate were added to 25g of methylene chloride and 20g of pure water and heated at 25°C for 1 hour. Stir. Thereafter, the layers are separated, and the collected organic layer is added dropwise to ethyl acetate for reprecipitation. This is filtered and vacuum dried to obtain 1.8 g of the desired polymer 4a.

(Synthesis Example 22) Synthesis of Polymer 5a 2.0g of Polymer 5 obtained in Synthesis Example 13 above and 0.05g of disodium tetrafluorosuccinate were added to 25g of methylene chloride and 20g of pure water and heated at 25°C for 1 hour. Stir. Thereafter, the layers are separated, and the collected organic layer is added dropwise to ethyl acetate for reprecipitation. This is filtered and vacuum dried to obtain 1.8 g of the desired polymer 5a.

(Synthesis Example 23) Synthesis of Polymer 6a 2.0g of Polymer 6 obtained in Synthesis Example 14 above and 0.05g of disodium tetrafluorosuccinate were added to 25g of methylene chloride and 20g of pure water and heated at 25°C for 1 hour. Stir. Thereafter, the layers are separated, and the collected organic layer is added dropwise to ethyl acetate for reprecipitation. This is filtered and vacuum dried to obtain 1.8 g of the desired polymer 6a.

The composition ratio of the above polymer was measured using a nuclear magnetic resonance apparatus (NMR) using a general quantitative method using 13C-NMR.
The anion ratio of unit D to unit A in the above polymers 1a to 6a was calculated by a general quantitative method using anion chromatography.

<Preparation of resist composition>
Among the above polymers, 50 mg of polymers 1a, 1b, 1e, 3a, 4a, 5a, and any of polymers 1, 3, and 4 as comparative samples were mixed with ethyl lactate and γ-butyrolactone at a ratio of 9:1. Resist composition samples 1 to 5 of Examples 1 to 5 and resist composition samples 6 to 8 of Comparative Examples 1 to 3 are prepared by dissolving the resist compositions in the respective solvents.

<Preparation of developer>
A developer was prepared as follows.
(1) Using resist composition samples 1 to 6 in which each of the above polymers was dissolved in a solvent containing a mixture of ethyl lactate and γ-butyrolactone at a ratio of 9:1, the composition was coated to a film thickness of 200 nm by spin coating. Prepare a film coated with
(2) Butyl acetate, amyl acetate, hexyl acetate, 2-heptanone, and propylene glycol monomethyl ether acetate (PGMEA) are prepared as a developer.
(3) Each film obtained in (1) above is immersed in a developer for 30 seconds. Thereafter, it is placed in a spin coater and rotated at 2000 rpm for 30 seconds to dry, and the film thickness is measured.
(4) Based on the film thickness measurement obtained in (3) above, an organic solvent with a residual film ratio of 70% or more is used as a developer for each resist composition sample.

<EUV exposure evaluation>
Resist composition sample 1 was dropped onto a 6-inch silicon wafer, spin-coated, and then baked on a hot plate at 110° C. for 1 minute to form a film with a thickness of 200 nm. The obtained film was irradiated with EUV using an EUV exposure device (manufactured by Energetiq Technology, EQ-10m), and then developed by being impregnated with a developer previously set for each sample for 30 seconds. After development, it was placed in a spin coater and rotated at 2000 rpm for 20 seconds to dry, thereby obtaining a 1×1 cm ² pattern. The film thickness of the exposed portion of the obtained pattern was measured using a contact film thickness meter (Surfcorder ET-200, manufactured by Kosaka Laboratory Co., Ltd.), and a sensitivity curve was created to determine the sensitivity (E ₀ ). The sensitivity of Sample 1 is compared by defining E ₀ as the exposure amount when the film thickness of the exposed portion becomes 5% or less of the initial film thickness. Furthermore, the film thickness of the unexposed area is measured and the remaining film rate after development is calculated.
For the resist composition samples 2 to 10, the sensitivity evaluation and residual film rate are calculated in the same manner as for the resist composition sample 1. Table 1 shows the results of comparing the sensitivities of each resist composition sample 2 to 10 using the sensitivity of resist composition sample 1 as a reference value, and calculating the relative sensitivity (E ₀ ) and the residual film rate in the unexposed area. The smaller the relative sensitivity (E ₀ ), the higher the sensitivity.

The combinations of Examples 1 to 3 and Comparative Example 1, Example 4 and Comparative Example 2, Example 5 and Comparative Example 3, and Example 6 and Comparative Example 4 have different valences of anions in the onium salt structure. Otherwise, the composition of the polymers is the same.
From a comparison of Examples 1 to 6 and Comparative Examples 1 to 4, even if the polymer compositions are similar except for the valence of the anion of the unit having an onium salt structure, the polymer of one embodiment of the present invention has unit A. It can be seen that by having a polyvalent anion, the solubility of the unexposed area in an organic solvent is significantly reduced. In the polymer of one embodiment of the present invention, the cationic part of unit A decomposes into an acid due to EUV exposure, and the exposed part dissolves in an organic solvent due to a decrease in the valence of the anion and a polarity change due to the decomposition of the cation. , it is possible to produce a larger development contrast compared to Comparative Examples 1 to 4 which do not have an anion of divalent or higher valence.

In the polymer of one embodiment of the present invention, the unit A has a polyvalent anion of divalent or higher valence, and the polymers are connected by ionic bonds. It has higher ionicity than polymers and has a large polymer size, so it has low solubility in organic solvents. On the other hand, when the polymer of one embodiment of the present invention is exposed to EUV or EB, unit A decomposes and becomes an acid, resulting in a decrease in ionicity, and furthermore, the polymer size becomes smaller, making it easier to dissolve in organic solvents. Become.

From the comparison between Example 1 and Example 2, polymer 1b of Example 2 has a higher organic solvent content than polymer 1a of Example 1 because increasing the composition of unit A increases the proportion of ionicity in the resist composition. It can be seen that the remaining film rate in the unexposed area is improved. However, since the polymer 1b of Example 2 needs to decompose more units A than the polymer 1b of Example 1, the relative sensitivity tends to decrease. From this result, polyvalent anions of trivalent or higher valence, such as Polymer 1c and Polymer 3e, can increase the ionic ratio of the polymer with a small amount of introduction, so they can effectively improve the solubility of the unexposed part of the polymer in organic solvents. can be expected to decline.

<EUV-UV exposure evaluation>
Resist composition sample 4 was dropped onto a 6-inch silicon wafer, spin coated, and then baked on a hot plate at 110° C. for 1 minute to form a film with a thickness of 200 nm. The obtained film was irradiated with EUV using an EUV exposure device (manufactured by Energetiq Technology, EQ-10m), and then the entire surface was irradiated with a 395 nm UV-LED at an exposure dose of 1000 mJ/cm ² . Thereafter, the sample was impregnated with a developer previously set for each sample for 60 seconds and developed. After developing, it was placed in a spin coater and rotated at 2000 rpm for 30 seconds to dry, thereby obtaining a 1×1 cm ² pattern.
The film thickness of the exposed portion of the obtained pattern was measured using a contact film thickness meter (Surfcorder ET-200, manufactured by Kosaka Laboratory Co., Ltd.), and a sensitivity curve was created to determine the sensitivity (E ₀ ). The sensitivity of resist composition sample 4 is compared by defining E ₀ as the exposure amount when the film thickness of the exposed area becomes 5% or less of the initial film thickness. Furthermore, the film thickness of the unexposed area is measured and the remaining film rate after development is calculated. For resist composition sample 6, sensitivity evaluation and residual film rate are calculated in the same manner as above. The sensitivity of resist composition sample 6 was compared using the sensitivity of resist composition sample 4 as a reference value, and Table 2 shows the calculation results of relative sensitivity and residual film rate in unexposed areas. The smaller the relative sensitivity (E ₀ ), the higher the sensitivity.

In Table 1 above, when comparing Example 4 and Example 6, polymer 3a and polymer 5a have similar sensitivity to EUV exposure. However, in Table 2, when comparing Example 7 and Example 8, polymer 5a has better sensitivity. This is because polymer 5a, which has compound A5 as unit A, has its acetal group deprotected by the acid generated after EUV irradiation, shifting the absorption peak wavelength of the polymer to a longer wavelength. When the longer wavelength polymer is irradiated with 395 nm UV, further acid is generated, making it more sensitive than polymer 3a, which has compound A1 as unit A.

Since the polymer of one embodiment of the present invention is a polymer containing an organometallic compound-containing unit B, the exposed portion can be dissolved by developing with an organic solvent as a developer after irradiating with EUV or EB. Furthermore, by including either of the above formulas (3) and (4) as the unit A, sensitivity is improved by UV irradiation, so a pattern can be formed with a reduced EUV exposure amount. Polymers according to some embodiments of the present invention and resist compositions containing the polymers are effective because they can reduce the amount of energy required for pattern formation.
Further, since the polymer of one embodiment of the present invention has unit B, it can be expected to have excellent etching resistance.
Even if it is a polymer other than the polymer evaluated in the example, if it has the above unit A and the above unit B, it will have the same excellent effects on sensitivity, development contrast characteristics, and etching characteristics as the polymer evaluated in the example. have

Some aspects of the present invention provide a polymer that has high absorption efficiency for particle beams such as EUV or electromagnetic waves and excellent sensitivity, development contrast characteristics, and etching resistance, and a resist composition containing the polymer. Can be done.

Claims (15)

A unit A that has an onium salt structure and generates acid by irradiation with particle beams or electromagnetic waves;
an organometallic compound-containing unit B having a metal atom selected from the group consisting of Sn, Sb, Ge, Bi and Te;
A polymer in which the unit A is represented by the following formula (1).

(In the general formula (1),
R ¹ is any one selected from the group consisting of a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms; and a linear, branched or cyclic alkenyl group having 2 to 6 carbon atoms; and at least one hydrogen atom in the alkyl group and alkenyl group in R ¹ may be substituted with a substituent,
L is a direct bond, a carbonyloxy group, a carbonylamino group, a phenylenediyl group, a naphthalenediyl group, a phenylenediyloxy group, a naphthalenediyloxy group, a phenylenediylcarbonyloxy group, a naphthalenediylcarbonyloxy group, a phenylenediyloxycarbonyl group, and Any one selected from the group consisting of naphthalenediyloxycarbonyl group,
Sp is a direct bond; a linear, branched or cyclic alkylene group having 1 to 6 carbon atoms which may have a substituent; and a straight chain, branched or cyclic carbon number which may have a substituent 2 to 6 alkenylene groups; at least one methylene group in the Sp may be substituted with a divalent heteroatom-containing group;
M ⁺ is a sulfonium cation group or an iodonium cation group,
X ⁻ is a monovalent anion group,
f is an integer from 2 to 4, and f X ⁻ bonded to the R, f M ⁺ corresponding to the X ⁻ , f R ¹ , f L and f Sp are: They may be the same or different from each other,
R is an f-valent hydrocarbon group having 1 to 6 carbon atoms which may have a substituent, at least one hydrogen atom in R may be substituted with a substituent, and at least one hydrogen atom in R may be substituted with a substituent; One methylene group may be substituted with a divalent heteroatom-containing group. ) A group in which X ^- is an alkyl sulfate anion; an aryl sulfate anion; an alkyl sulfonate anion; an aryl sulfonate anion; an alkyl carboxylate anion; an aryl carboxylate anion; a dialkyl sulfonylimide anion; a trialkyl sulfonate methide anion; a tetrakis phenyl borate anion; one selected from
At least one hydrogen atom of the alkyl group and aryl group in X ^- may be substituted with a substituent, and at least one methylene group in the alkyl group in X ^- may be substituted with a divalent heteroatom-containing group. 2. The polymer according to claim 1, which may be The polymer according to claim 1 or 2, wherein the unit A is represented by the following formula (2):

(In the general formula (2),
R ¹ , L, Sp, X ^- and f are selected from the same options as R ¹ , L, Sp, X ^- and f in the general formula (1), respectively;
R ^6a is any one selected from the group consisting of a linear, branched or cyclic alkylene group having 1 to 6 carbon atoms which may have a substituent; a linear, branched or cyclic alkenylene group having 2 to 6 carbon atoms which may have a substituent; an arylene group having 6 to 14 carbon atoms which may have a substituent; a heteroarylene group having 4 to 12 carbon atoms which may have a substituent; and a direct bond; and at least one methylene group in R ^6a may be substituted with a divalent heteroatom-containing group,
R ^6b is independently any one selected from the group consisting of an optionally substituted linear, branched or cyclic alkyl group having 1 to 6 carbon atoms; an optionally substituted linear, branched or cyclic alkenyl group having 2 to 6 carbon atoms; an optionally substituted aryl group having 6 to 14 carbon atoms; and an optionally substituted heteroaryl group having 4 to 12 carbon atoms, wherein at least one methylene group in R ^6b is optionally substituted with a divalent heteroatom-containing group,
R ^6a and two of the two R ^6b may form a ring structure with the sulfur atom to which they are bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and a methylene group;
The f X ⁻ , f R ^6a , f R ^6b , f R ¹ , f L and f Sp bonded to R may be the same or different from each other. The polymer according to any one of claims 1 to 3, wherein the M ⁺ is represented by the following general formula (3) or the following formula (4).

(In the above formula (3), R ¹¹ and R ¹² each independently represent a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; A straight chain, branched or cyclic alkenyl group having 2 to 12 carbon atoms which may have a substituent; an aryl group having 6 to 14 carbon atoms which may have a substituent; a heteroaryl group having 4 to 12 carbon atoms;
Any two or more of the aryl groups to which R ¹¹ , R ¹² and the sulfonium group are bonded may be directly bonded by a single bond, or may be a group consisting of an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and a methylene group. These may form a ring structure together with the sulfur atom to which they are bonded via any one selected from
At least one methylene group in R ¹¹ and R ¹² may be substituted with a divalent heteroatom-containing group,
R ¹³ and R ¹⁴ independently each represent an alkyl group, a hydroxy group, a mercapto group, an alkyleneoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkyleneoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group. group, alkylsulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, (meth)acryloyloxy group, hydroxy(poly)alkyleneoxy group, amino group , a cyano group, a nitro group, and a halogen atom, and if it has carbon, the number of carbon atoms is 1 to 12, and these may have a substituent,
One R ¹⁴ forms a ring structure with the aryl group to which the R ¹⁴ is bonded via any one selected from the group consisting of a direct bond, a methylene group, an oxygen atom, a sulfur atom, and a divalent nitrogen atom-containing group. It may be formed,
R ¹⁵ and R ¹⁶ each independently represent a straight chain, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent; a straight chain which may have a substituent; A branched or cyclic alkenyl group having 2 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and a hetero group having 4 to 12 carbon atoms which may have a substituent Any one selected from the group consisting of: aryl group;
The R ¹⁵ and R ¹⁶ may be bonded to each other to form a ring structure directly with a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and an alkylene group,
At least one methylene group in R ¹⁵ and R ¹⁶ may be substituted with a divalent heteroatom-containing group,
L ² is a direct bond; a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms; an alkenylene group having 2 to 12 carbon atoms; an arylene group having 6 to 14 carbon atoms; Any one selected from the group consisting of a heteroarylene group; and a group in which these groups are bonded via an oxygen atom, a sulfur atom, or a divalent nitrogen atom-containing group;
^L3 is selected from the group consisting of a direct bond, a methylene group, a sulfur atom, a divalent nitrogen atom-containing group, and an oxygen atom,
Y is an oxygen atom or a sulfur atom,
h is an integer from 1 to 2,
i is an integer from 1 to 3,
j is an integer from 0 to 3 when h is 1, and from 0 to 5 when h is 2;
k is an integer from 0 to 4 when i is 1, from 0 to 6 when i is 2, and from 0 to 8 when i is 3;

Any one hydrogen among R ¹¹ , R ¹² and R ¹⁴ and the hydrogen atom on the aryl ring to which R ¹⁴ is bonded are replaced by a bond with Sp in the above formula (1),
In the formula (4), R ¹¹ to R ¹⁶ , L ² and Y are each independently selected from the same options as each of R ¹¹ to R ¹⁶ , L ² and Y in the formula (3),
h is an integer from 1 to 2,
i is an integer from 1 to 3,
j is an integer from 0 to 4 when h is 1, and from 0 to 6 when h is 2;
k is an integer from 0 to 5 when i is 1, from 0 to 7 when i is 2, and from 0 to 9 when i is 3;
L ⁴ and L ⁵ are each independently selected from the group consisting of a direct bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, and a carbonyl group. )) The polymer according to any one of claims 1 to 4, further comprising a unit D, wherein the unit D is represented by the following formula (1).

(In the general formula (6), R ¹ , L, Sp, and M ⁺ are selected from the same options as R ¹ , L, Sp, and M ⁺ described in the general formula (1), and Z ⁻ is 1 (It is an anion of valence.) The polymer according to any one of claims 1 to 5, wherein the molar ratio of unit D to unit A is 0 to 20. A claim further comprising a unit C, wherein the unit C is a unit in which a compound represented by the following general formula (I) or (II) is bonded to an Sp group of the following formula (5) at any position of the compound. The polymer according to any one of items 1 to 6.

(In the general formula (I),
R ² and R ³ are each independently selected from the group consisting of a hydrogen atom; an electron-donating group; and an electron-withdrawing group;
E is any one selected from the group consisting of a direct bond; an oxygen atom; a sulfur atom; and a methylene group;
R ⁴ is any one selected from the group consisting of an alkyl group that may have a substituent; and an alkenyl group that may have a substituent;
n ¹ is an integer of 0 or 1,
n ⁴ and n ⁵ are each an integer of 1 to 2, n ⁴ + n ⁵ is 2 to 4,
When n ⁴ is 1, n ² is an integer from 0 to 4; when n ⁴ is 2, n ² is an integer from 0 to 6;
When n ⁵ is 1, n ³ is an integer from 0 to 4; when n ⁵ is 2, n ³ is an integer from 0 to 6;
When n ² is 2 or more and R ² is an electron-donating group or an electron-withdrawing group, the two R ^2s are directly connected by a single bond, or an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and A ring structure may be formed with each other via any one selected from the group consisting of methylene groups,
When n ³ is 2 or more and R ³ is an electron-donating group or an electron-withdrawing group, two R ^3s are directly connected to each other by a single bond, or an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and A ring structure may be formed with each other via any one selected from the group consisting of methylene groups.
In the general formula (II),
R ⁴ is any one selected from the group consisting of an alkyl group that may have a substituent; and an alkenyl group that may have a substituent;
R ⁵ is any one selected from the group consisting of a hydrogen atom; an alkyl group that may have a substituent; and an alkenyl group that may have a substituent; and at least one of the R ⁵ The methylene group may be substituted with a divalent heteroatom-containing group, and the R ⁵ may form a ring structure together with a benzene ring to which the hydroxymethylene group having the R ⁵ is bonded,
R ⁶ is each independently selected from the group consisting of a hydrogen atom; an electron-donating group; and an electron-withdrawing group;
At least one of R ⁶ is the electron donating group,
n ⁶ is an integer from 0 to 7,
n ⁷ is 1 or 2; when n ⁷ is 1, n ⁶ is an integer from 0 to 5; when n ⁷ is 2, n ⁶ is an integer from 0 to 7;
When n ⁶ is 2 or more and R ⁴ is an electron-donating group or an electron-withdrawing group, two R ^4s are directly connected to each other by a single bond, or an oxygen atom, a sulfur atom, a divalent nitrogen atom-containing group, and A ring structure may be formed with each other via any one selected from the group consisting of methylene groups. )

(In the above formula (5),
R ¹ , L and Sp are each selected from the same options as R ¹ , L and Sp in the general formula (1),
* indicates a bonding site with the compound represented by the general formula (I) or (II). )
A resist composition containing the polymer according to any one of claims 1 to 7. A resist film forming step of forming a resist film on a substrate using the resist composition according to claim 8;
a photolithography step of exposing the resist film using particle beams or electromagnetic waves;
a pattern forming step of developing the exposed resist film using a developer to dissolve the exposed area and obtain a photoresist pattern;
A method for manufacturing a member including. The method for manufacturing a member according to claim 9, wherein the developer is an organic solvent. The method for manufacturing a member according to claim 9 or 10, wherein in the photolithography step, after exposure to the particle beam or electromagnetic wave, a second active energy ray having a lower energy than the particle beam or electromagnetic wave is further irradiated. The method for manufacturing a member according to any one of claims 9 to 11, wherein the particle beam is an electron beam and the electromagnetic wave is extreme ultraviolet rays. A resist film forming step of forming a resist film on a substrate using the resist composition according to claim 8;
a photolithography step of exposing the resist film using particle beams or electromagnetic waves;
A pattern forming method comprising a pattern forming step of developing the exposed resist film using a developer to dissolve exposed areas and obtain a photoresist pattern. The pattern forming method according to claim 13, wherein the developer is an organic solvent. The pattern forming method according to claim 13 or 14, wherein in the photolithography step, after exposure to the particle beam or electromagnetic wave, a second active energy ray having a lower energy than the particle beam or electromagnetic wave is further irradiated.