JP5716744B2 - Radiation sensitive composition and novel compound - Google Patents

Description

  The present invention relates to a radiation-sensitive composition and a novel compound used in a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal and a thermal head, and other photolithography processes. More specifically, the present invention relates to a radiation-sensitive composition suitable for a photolithography process using an exposure light source such as far ultraviolet rays of 220 nm or less, for example, an ArF excimer laser or an electron beam, and the radiation-sensitive composition. The present invention relates to a novel compound suitable as an acid generator to be blended.

  The chemically amplified radiation-sensitive resin composition generates an acid in an exposed area by irradiation with far ultraviolet light or the like typified by a KrF excimer laser or an ArF excimer laser. And a composition for changing the dissolution rate of the unexposed portion in the developer to form a resist pattern on the substrate (see Patent Document 1 and Non-Patent Document 1).

  The radiation-sensitive acid generator contained in such a chemically amplified radiation-sensitive resin composition has the characteristics of being excellent in transparency to radiation and having a high quantum yield upon acid generation. Desired. Furthermore, the acid generated by the radiation sensitive acid generator is sufficiently strong, has a sufficiently high boiling point, and has an appropriate diffusion distance in the resist film (hereinafter sometimes referred to as “diffusion length”). Characteristics are required.

Among the above-mentioned properties, the structure of the anion moiety is important in an ionic radiation-sensitive acid generator in order to exhibit acid strength, boiling point, and diffusion length.
For example, a radiation-sensitive acid generator having a trifluoromethanesulfonyl structure generates a sufficiently strong acid, and the resolution performance as a photoresist is sufficiently high. However, the boiling point of the acid is low and the acid diffusion length is not appropriate. That is, since the acid diffusion length is long, the resolution performance is not sufficient.
In addition, a radiation-sensitive acid generator having a sulfonyl structure bonded to a large organic group such as a 10-camphorsulfonyl structure has a sufficiently high boiling point of the generated acid and an appropriate acid diffusion length. That is, the acid diffusion length is sufficiently short. However, the radiation-sensitive acid generator having a camphorsulfonyl structure has a disadvantage that it is poorly soluble and difficult to dissolve in a solvent generally used in radiation-sensitive resin compositions.

  On the other hand, when more precise line width control is performed, for example, when the device design dimension is sub-half micron or less, the chemically amplified resist has not only excellent resolution performance but also a resist pattern. It is also important that the smoothness of the film surface after formation is excellent. For chemically amplified resists with poor film surface smoothness, when the resist pattern is transferred to the substrate by etching or other treatment, the uneven surface shape of the film surface (hereinafter sometimes referred to as “nano edge roughness”) is transferred to the substrate. As a result, the dimensional accuracy of the pattern is lowered. Therefore, it has been reported that there is a possibility that the electrical characteristics of the device may be ultimately lost (for example, see Non-Patent Documents 2 to 5).

JP 59-45439 A

Perfluorinated Sulfonates; Proposed Significant New Use Rule J. et al. Photopolym. Sci. Tech. , P. 571 (1998) Proc. SPIE, Vol. 3333, p. 313 Proc. SPIE, Vol. 3333, p. 634 J. et al. Vac. Sci. Technol. B16 (1), p. 69 (1998)

  The present invention has been made in view of the above circumstances, and provides a radiation-sensitive composition capable of forming a chemically amplified resist having high solubility in a solvent, excellent resolution, and low nanoedge roughness. The purpose is to do.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that the problems can be achieved by using a radiation-sensitive composition containing a sulfonic acid onium salt having a specific structure. The invention has been completed.

〔一般式（１）において、Ｒ^１は相互に独立に、水素原子、フッ素原子、又は、水素原子の一部若しくは全てがフッ素原子で置換された炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基を示し、且つＲ^１のうち少なくとも１つは、フッ素原子、又は水素原子の一部若しくは全部がフッ素原子で置換された炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基を示す。Ｒ^２は相互に独立に、−ＣＯＯＲ ^ａ 基を示す。Ｒ ^ａ は相互に独立に、（ａ１）置換若しくは非置換の炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基、（ａ２）エステル結合、アミド結合、ウレタン結合及びスルフィド結合から選ばれる連結基を更に有する前記炭化水素基（ａ１）、（ａ３）置換若しくは非置換の炭素数３〜３０の環状若しくは環状構造を有する１価の脂肪族炭化水素基、（ａ４）エステル結合、アミド結合、ウレタン結合及びスルフィド結合から選ばれる連結基を更に有する前記脂肪族炭化水素基（ａ３）、（ａ５）置換若しくは非置換の炭素数６〜３０のアリール基、又は、（ａ６）置換若しくは非置換の炭素数４〜３０の１価のヘテロ原子を有してもよい環状有機基を示す。ｎは０〜３の整数を示す。Ｍ^＋は１価のオニウムカチオンを示す。〕
［２］前記感放射線性酸発生剤が、下記一般式（２）で表される感放射線性酸発生剤である前記［１］に記載の感放射線性組成物。

〔一般式（２）において、Ｒ^３は相互に独立に、水素原子、フッ素原子、又は、水素原子の一部若しくは全てがフッ素原子で置換された炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基を示し、且つＲ^３のうち少なくとも１つは、フッ素原子、又は水素原子の一部若しくは全てがフッ素原子で置換された炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基を示す。Ｒ^４は相互に独立に、（ａ１）置換若しくは非置換の炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基、（ａ２）エステル結合、アミド結合、ウレタン結合及びスルフィド結合から選ばれる連結基を更に有する前記炭化水素基（ａ１）、（ａ３）置換若しくは非置換の炭素数３〜３０の環状若しくは環状構造を有する１価の脂肪族炭化水素基、（ａ４）エステル結合、アミド結合、ウレタン結合及びスルフィド結合から選ばれる連結基を更に有する前記脂肪族炭化水素基（ａ３）、（ａ５）置換若しくは非置換の炭素数６〜３０のアリール基、又は、（ａ６）置換若しくは非置換の炭素数４〜３０の１価のヘテロ原子を有してもよい環状有機基を示す。Ｍ^＋は１価のオニウムカチオンを示す。〕
［３］前記一般式（２）におけるＲ^３のうち少なくとも１つが、フッ素原子又はトリフルオロメチル基である前記［２］に記載の感放射線性組成物。
［４］前記一般式（２）におけるＲ^４が、相互に独立に、（ａ３）置換若しくは非置換の炭素数３〜３０の環状若しくは環状構造を有する１価の脂肪族炭化水素基、（ａ４）エステル結合、アミド結合、ウレタン結合及びスルフィド結合から選ばれる連結基を更に有する前記炭化水素基（ａ３）、又は、（ａ５）置換若しくは非置換の炭素数６〜３０のアリール基である前記［２］又は［３］に記載の感放射線性組成物。
［５］前記一般式（１）又は（２）における１価のオニウムカチオン（Ｍ^＋）が、下記一般式（ｍ１−１）で示されるスルホニウムカチオンである前記［１］乃至［４］のいずれかに記載の感放射線性組成物。

〔一般式（ｍ１−１）において、Ｒ^１１１〜Ｒ^１１３は、各々独立に、ヒドロキシ基、ハロゲン原子、置換基を有していてもよいアルキル基、シクロアルキル基、アルコキシ基、−Ｓ−Ｒ^１１４基（Ｒ^１１４は置換基を有していてもよいアルキル基、又はアリール基を示す。）、又は、−ＳＯ_２−Ｒ^１１５基（Ｒ^１１５は、置換基を有していてもよいアルキル基、シクロアルキル基、アルコキシ基、又はアリール基を示す。）を示す。但し、Ｒ^１１１のうち少なくとも１つは−ＳＯ_２−Ｒ^１１５基である。ｌは１〜５の整数である。ｍは０〜５の整数である。ｎは０〜５の整数である。〕
［６］更に、下記一般式（ｂ−１）〜（ｂ−５）で表される繰り返し単位のうちの少なくとも１種を含む樹脂を含有する前記［１］乃至［５］のいずれかに記載の感放射線性組成物。

〔一般式（ｂ−１）において、Ｒ^１１は、水素原子又はメチル基を示す。Ｒ^１２は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシ基を示す。ｋは０〜３の整数を示し、ｌは０〜３の整数を示し、且つｋ＋ｌ≦５を満たす。〕

〔一般式（ｂ−２）において、Ｒ^１３は、水素原子又はメチル基を示す。Ｒ^１４は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシ基を示す。ｍは０〜３の整数を示し、ｎは０〜３の整数を示し、且つｍ＋ｎ≦５を満たす。〕

〔一般式（ｂ−３）において、Ｒ^１５は、水素原子又はメチル基を示す。Ｒ^１６は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシ基を示す。ｐは０〜３の整数を示し、ｑは０〜３の整数を示し、且つｐ＋ｑ≦５を満たす。〕

〔一般式（ｂ−４）において、Ｒ^１７は、水素原子又はメチル基を示す。Ｒ^１８は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシ基を示す。ｒは０〜３の整数を示し、ｓは０〜３の整数を示す。〕

〔一般式（ｂ−５）において、Ｒ^１９は、水素原子又はメチル基を示す。〕
［７］下記一般式（１）で示されることを特徴とする化合物。

〔一般式（１）において、Ｒ^１は相互に独立に、水素原子、フッ素原子、フルオロアルキルを示し、且つＲ^１のうち少なくとも１つは、フッ素原子、又はフルオロアルキルを示す。Ｒ^２は相互に独立に、アルコキシカルボニル（アルコキシ基は、フッ素原子で置換されていてもよい）、シクロアルコキシカルボニル（シクロアルキル基は、縮合多環式ラクトンを包含する）を示す。ｎは１を示す。Ｍ^＋は１価の有機スルホニウムカチオンを示す。〕 The present invention is as follows.
[1] A radiation-sensitive composition comprising a radiation-sensitive acid generator represented by the following general formula (1) and a solvent.

[In General Formula (1), R ¹ is independently a hydrogen atom, a fluorine atom, or a linear or branched group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms are substituted with fluorine atoms. And at least one of R ¹ is a fluorine atom or a linear or branched group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms are substituted with fluorine atoms. These are monovalent hydrocarbon groups . R ² independently represents ^a —COOR ^a group. R ^a is independently of each other: (a1) a substituted or unsubstituted linear or branched monovalent hydrocarbon group having 1 to 30 carbon atoms, (a2) an ester bond, an amide bond, a urethane bond and a sulfide bond. The hydrocarbon group (a1), (a3) a substituted or unsubstituted monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms, or (a4) an ester bond The aliphatic hydrocarbon group (a3) further having a linking group selected from an amide bond, a urethane bond and a sulfide bond, (a5) a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or (a6) a substituted group Alternatively, it represents a cyclic organic group which may have an unsubstituted monovalent heteroatom having 4 to 30 carbon atoms . n represents an integer of 0 to 3. M ⁺ represents a monovalent onium cation. ]
[2] The radiation-sensitive composition according to [1], wherein the radiation-sensitive acid generator is a radiation-sensitive acid generator represented by the following general formula (2).

[In General Formula (2), R ³ is independently a hydrogen atom, a fluorine atom, or a linear or branched group having 1 to 30 carbon atoms in which some or all of the hydrogen atoms are substituted with fluorine atoms. And at least one of R ³ is a fluorine atom or a linear or branched group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms are substituted with fluorine atoms These are monovalent hydrocarbon groups. R ⁴ is independently of each other (a1) a substituted or unsubstituted C 1-30 linear or branched monovalent hydrocarbon group, (a2) an ester bond, an amide bond, a urethane bond and a sulfide bond. The hydrocarbon group (a1), (a3) a substituted or unsubstituted monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms, or (a4) an ester bond The aliphatic hydrocarbon group (a3) further having a linking group selected from an amide bond, a urethane bond and a sulfide bond, (a5) a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or (a6) a substituted group Alternatively, it represents a cyclic organic group which may have an unsubstituted monovalent heteroatom having 4 to 30 carbon atoms. M ⁺ represents a monovalent onium cation. ]
[3] The radiation-sensitive composition according to [2], wherein at least one of R ³ in the general formula (2) is a fluorine atom or a trifluoromethyl group.
[4] R ⁴ in the general formula (2) are, independently of each other, (a3) a substituted or unsubstituted monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms, (a4 ) The hydrocarbon group (a3) further having a linking group selected from an ester bond, an amide bond, a urethane bond and a sulfide bond, or (a5) the substituted or unsubstituted aryl group having 6 to 30 carbon atoms [ The radiation-sensitive composition according to [2] or [3].
[5] Any of [1] to [4], wherein the monovalent onium cation (M ⁺ ) in the general formula (1) or (2) is a sulfonium cation represented by the following general formula (m1-1) A radiation-sensitive composition according to claim 1.

[In General Formula (m1-1), R ^{111 to} R ¹¹³ are each independently a hydroxy group, a halogen atom, an alkyl group which may have a substituent, a cycloalkyl group, an alkoxy group, or —SR. ¹¹⁴ group (R ¹¹⁴ represents an alkyl group which may have a substituent or an aryl group), or —SO ₂ —R ¹¹⁵ group (R ¹¹⁵ is an alkyl which may have a substituent). A group, a cycloalkyl group, an alkoxy group, or an aryl group. However, at least one of R ¹¹¹ is a —SO ₂ —R ¹¹⁵ group. l is an integer of 1-5. m is an integer of 0-5. n is an integer of 0-5. ]
[6] The method according to any one of [1] to [5], further including a resin including at least one of repeating units represented by the following general formulas (b-1) to (b-5). Radiation sensitive composition.

[In General Formula (b-1), R ¹¹ represents a hydrogen atom or a methyl group. R ¹² represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. k represents an integer of 0 to 3, l represents an integer of 0 to 3, and k + l ≦ 5 is satisfied. ]

[In General Formula (b-2), R ¹³ represents a hydrogen atom or a methyl group. R ¹⁴ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. m represents an integer of 0 to 3, n represents an integer of 0 to 3, and satisfies m + n ≦ 5. ]

[In General Formula (b-3), R ¹⁵ represents a hydrogen atom or a methyl group. R ¹⁶ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. p represents an integer of 0 to 3, q represents an integer of 0 to 3, and satisfies p + q ≦ 5. ]

[In General Formula (b-4), R ¹⁷ represents a hydrogen atom or a methyl group. R ¹⁸ represents a linear or branched alkyl group having 1 to 12 carbon atoms or a linear or branched alkoxy group having 1 to 12 carbon atoms. r represents an integer of 0 to 3, and s represents an integer of 0 to 3. ]

[In General Formula (b-5), R ¹⁹ represents a hydrogen atom or a methyl group. ]
[7] A compound represented by the following general formula (1):

In [general formula (1), R ¹ independently of one another, a hydrogen atom, a fluorine atom, a fluoroalkyl, and at least one of R ¹ represents a fluorine atom, or a fluoroalkyl. R ² independently represents alkoxycarbonyl (the alkoxy group may be substituted with a fluorine atom) or cycloalkoxycarbonyl (the cycloalkyl group includes a condensed polycyclic lactone) . n represents 1 . M ⁺ represents a monovalent organic sulfonium cation. ]

The radiation sensitive composition of the present invention is sensitive to X-rays such as KrF excimer laser, ArF excimer laser, EUV (extreme) deep ultraviolet rays, synchrotron radiation, and electron beams, and nano edge roughness, sensitivity and resolution. And a chemically amplified positive resist film capable of forming a fine pattern with high accuracy and stability.
Moreover, since the novel compound of the present invention has high solubility in a solvent and a sufficiently short acid diffusion length, it can be suitably used as a radiation-sensitive acid generator in the above-mentioned radiation-sensitive composition.

It is a typical top view at the time of seeing a line pattern from the upper part. It is typical sectional drawing of a line pattern shape.

Hereinafter, although the form for implementing this invention is demonstrated, this invention is not limited to the following embodiment. That is, it is understood that modifications and improvements as appropriate to the following embodiments are within the scope of the present invention based on the ordinary knowledge of those skilled in the art without departing from the spirit of the present invention. Should be.
Further, “(meth) acrylate” in the present specification means “acrylate” or “methacrylate”.

[1] Radiation-sensitive composition The radiation-sensitive composition of the present invention contains a specific radiation-sensitive acid generator and a solvent.

[1-1] Radiation sensitive acid generator (A)
The radiation-sensitive acid generator [hereinafter also referred to as “acid generator (A)”. ] Consists of a compound represented by the following general formula (1). The acid generator (A) has high solubility in a solvent, and according to the radiation-sensitive composition containing the acid generator (A), a resist film capable of obtaining a good resist pattern is formed. Can do. Further, the acid generator (A) has a high boiling point, hardly volatilizes during the photolithography process, and has a short acid diffusion length in the resist film. That is, it has a characteristic that the acid diffusion length is moderate.

〔一般式（１）において、Ｒ^１は相互に独立に、水素原子、フッ素原子、又は、水素原子の一部若しくは全てがフッ素原子で置換された炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基を示し、且つＲ^１のうち少なくとも１つは、フッ素原子、又は水素原子の一部若しくは全部がフッ素原子で置換された炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基を示す。Ｒ^２は相互に独立に、−ＣＯＯＲ ^ａ 基を示す。Ｒ ^ａ は相互に独立に、（ａ１）置換若しくは非置換の炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基、（ａ２）エステル結合、アミド結合、ウレタン結合及びスルフィド結合から選ばれる連結基を更に有する前記炭化水素基（ａ１）、（ａ３）置換若しくは非置換の炭素数３〜３０の環状若しくは環状構造を有する１価の脂肪族炭化水素基、（ａ４）エステル結合、アミド結合、ウレタン結合及びスルフィド結合から選ばれる連結基を更に有する前記脂肪族炭化水素基（ａ３）、（ａ５）置換若しくは非置換の炭素数６〜３０のアリール基、又は、（ａ６）置換若しくは非置換の炭素数４〜３０の１価のヘテロ原子を有してもよい環状有機基を示す。ｎは０〜３の整数を示す。Ｍ^＋は１価のオニウムカチオンを示す。〕

[In General Formula (1), R ¹ is independently a hydrogen atom, a fluorine atom, or a linear or branched group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms are substituted with fluorine atoms. And at least one of R ¹ is a fluorine atom or a linear or branched group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms are substituted with fluorine atoms. These are monovalent hydrocarbon groups . R ² independently represents ^a —COOR ^a group. R ^a is independently of each other: (a1) a substituted or unsubstituted linear or branched monovalent hydrocarbon group having 1 to 30 carbon atoms, (a2) an ester bond, an amide bond, a urethane bond and a sulfide bond. The hydrocarbon group (a1), (a3) a substituted or unsubstituted monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms, or (a4) an ester bond The aliphatic hydrocarbon group (a3) further having a linking group selected from an amide bond, a urethane bond and a sulfide bond, (a5) a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or (a6) a substituted group Alternatively, it represents a cyclic organic group which may have an unsubstituted monovalent heteroatom having 4 to 30 carbon atoms . n represents an integer of 0 to 3. M ⁺ represents a monovalent onium cation. ]

Examples of the monovalent hydrocarbon group having a linear or branched carbon number 1 to 30 that put the R ¹ in the general formula (1), for example, a methyl group, an ethyl group, n- propyl group, i- propyl N-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n-octyl group, i-octyl group, n-nonyl group , Hydrocarbon groups such as n-decyl group, 2-ethylhexyl group, and n-dodecyl group.

One or more hydrogen atoms in the hydrocarbon group for R ¹ may be substituted with a fluorine atom .
In addition, at least one of R ¹ in the general formula (1) is a linear or branched monovalent having 1 to 30 carbon atoms in which a fluorine atom or a part or all of a hydrogen atom is substituted with a fluorine atom. It is a hydrocarbon group .

Examples of the organic group represented by R ² include groups represented by the following formulas (1-1a-1) to (1-1a-4) . In the present invention, the following formula (1 ) can be given. -1a-2).

In general formulas (1-1a-1) and (1-1a-2), the group represented by R ^a is (a1) a substituted or unsubstituted linear or branched monovalent group having 1 to 30 carbon atoms. (A2) the hydrocarbon group (a1) further having a linking group selected from an ester bond, an amide bond, a urethane bond and a sulfide bond, (a3) a substituted or unsubstituted cyclic group having 3 to 30 carbon atoms Or a monovalent aliphatic hydrocarbon group having a cyclic structure, (a4) the above aliphatic hydrocarbon groups (a3) and (a5) substituted further having a linking group selected from an ester bond, an amide bond, a urethane bond and a sulfide bond Or an unsubstituted aryl group having 6 to 30 carbon atoms, or (a6) a substituted or unsubstituted cyclic organic group that may have a monovalent heteroatom having 4 to 30 carbon atoms.

X in the general formula (1-1a-2) represents a single bond.
X in the general formulas (1-1a- 3 ) to (1-1a-4) is a single bond, a methylene group, an alkylene group having 2 to 10 carbon atoms, an alicyclic hydrocarbon group having 3 to 30 carbon atoms, or An aryl group having 6 to 30 carbon atoms is represented.
Y in the general formula (1-1a-3) represents a methylene group or an alkylene group having 2 to 6 carbon atoms.
Z in the general formula (1-1a-4) represents a methylene group, an ethylene group, an oxygen atom, or a sulfur atom.

Examples of the unsubstituted linear or branched monovalent hydrocarbon group having 1 to 30 carbon atoms in R ^a of the general formulas (1-1a-1) and (1-1a-2) include, for example, a methyl group , Ethyl group, n-propyl group, i-propyl group, n-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n -Octyl group, i-octyl group, n-nonyl group, n-decyl group, 2-ethylhexyl group, n-dodecyl group and the like can be mentioned.

  In addition, examples of the substituent of the linear or branched monovalent hydrocarbon group having 1 to 30 carbon atoms include halogen atoms such as fluorine, chlorine, bromine and iodine, hydroxy groups, thiol groups, and aryls. And an organic group such as an alkyl group containing a group, an alkenyl group, and a hetero atom (for example, a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom). Furthermore, a keto group in which two hydrogen atoms on the same carbon of a hydrocarbon group are substituted with one oxygen atom can be exemplified. Any number of these substituents may be present as long as structurally possible.

  Examples of the linear or branched monovalent hydrocarbon group having 1 to 30 carbon atoms substituted with such a substituent include benzyl, methoxymethyl, methylthiomethyl, ethoxymethyl, and phenoxymethyl. Group, methoxycarbonylmethyl group, ethoxycarbonylmethyl group, acetylmethyl group, fluoromethyl group, trifluoromethyl group, 2,2,2-trifluoroethyl group, chloromethyl group, trichloromethyl group, 2-fluoropropyl group, Trifluoroacetylmethyl group, trichloroacetylmethyl group, pentafluorobenzoylmethyl group, aminomethyl group, cyclohexylaminomethyl group, diphenylphosphinomethyl group, trimethylsilylmethyl group, 2-phenylethyl group, 3-phenylpropyl group, 2- Aminoethyl group, hydroxy Methyl group, a hydroxyethyl group, and hydroxycarbonyl methyl group and the like.

  In addition, the hydrocarbon group further having a linking group selected from an ester bond, an amide bond, a urethane bond, and a sulfide bond [the above (a2)] is a substituted or unsubstituted straight chain having 1 to 30 carbon atoms or Examples include a group in which at least one selected from an ester bond, an amide bond, a urethane bond, and a sulfide bond is inserted in a part of the branched monovalent hydrocarbon group [above (a1)].

Examples of the monovalent aliphatic hydrocarbon group having an unsubstituted C3-C30 cyclic or cyclic structure in R ^a of the general formulas (1-1a-1) and (1-1a-2) include, for example, cyclo Propyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, bornyl group, norbornyl group, adamantyl group, pinanyl group, tyoyl group, caryl group, camphanyl group, cyclopropylmethyl group, cyclobutylmethyl group, cyclopentylmethyl group, cyclohexylmethyl group , Bornylmethyl group, norbornylmethyl group, adamantylmethyl group and the like.

  Moreover, as a substituent of the monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms, the linear or branched monovalent hydrocarbon having 1 to 30 carbon atoms is used. The thing similar to the substituent of group can be mentioned.

  Examples of the monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms and substituted with such a substituent include, for example, 4-fluorocyclohexyl group, 4-hydroxycyclohexyl group, 4-methoxycyclohexyl. Group, 4-methoxycarbonylcyclohexyl group, 3-hydroxy-1-adamantyl group, 3-methoxycarbonyl-1-adamantyl group, 3-hydroxycarbonyl-1-adamantyl group, 3-hydroxymethyl-1-adamantanemethyl group and the like Is mentioned.

  Moreover, as the hydrocarbon group [above (a4)] further having a linking group selected from an ester bond, an amide bond, a urethane bond and a sulfide bond, the above-mentioned substituted or unsubstituted C3-C30 cyclic or cyclic structure A group in which a part of the carbon-carbon bond constituting the ring in the monovalent aliphatic hydrocarbon group having a substituent is substituted with at least one selected from an ester bond, an amide bond, a urethane bond and a sulfide bond. it can.

Examples of the aryl group having 6 to 30 carbon atoms in R ^a of the general formulas (1-1a-1) and (1-1a-2) include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, and 1-anthryl. Group, 1-phenanthryl group and the like.

  Examples of the substituent for the aryl group having 6 to 30 carbon atoms include halogen atoms such as fluorine, chlorine, bromine and iodine, hydroxy groups, thiol groups, alkyl groups, and hetero atoms (for example, halogen atoms, oxygen atoms). An organic group containing an atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, etc.).

  Examples of the aryl group having 6 to 30 carbon atoms substituted with such a substituent include, for example, an o-hydroxyphenyl group, an m-hydroxyphenyl group, a p-hydroxyphenyl group, and a 3,5-bis (hydroxy) phenyl group. , O-tolyl group, m-tolyl group, p-tolyl group, p-methoxyphenyl group, mesityl group, o-cumenyl group, 2,3-xylyl group, o-fluorophenyl group, m-fluorophenyl group, p -Fluorophenyl group, o-trifluoromethylphenyl group, m-trifluoromethylphenyl group, p-trifluoromethylphenyl group, 3,5-bis (trifluoromethyl) phenyl group, p-bromophenyl group, p- A chlorophenyl group, p-iodophenyl group, etc. are mentioned.

Examples of the cyclic organic group which may have a monovalent heteroatom having 4 to 30 carbon atoms in R ^a of the general formulas (1-1a-1) and (1-1a-2) include a furyl group and thienyl. And groups derived from a group, pyranyl group, pyrrolyl group, thiantenyl group, pyrazolyl group, isothiazolyl group, isoxazolyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, and monocyclic or polycyclic lactone.
Monocyclic or polycyclic lactones include γ-butyrolaclone, γ-valerolactone, angelica lactone, γ-hexalactone, γ-heptalactone, γ-octalactone, γ-nonalactone, 3-methyl-4-octanolide (whiskey) Lactone), γ-decalactone, γ-undecalactone, γ-dodecalactone, γ-jasmolactone (7-decenolactone), δ-hexalactone, 4,6,6 (4,4,6) -trimethyltetrahydropyran -2-one, δ-octalactone, δ-nonalactone, δ-decalactone, δ-2-decenolactone, δ-undecalactone, δ-dodecalactone, δ-tridecalactone, δ-tetradecalactone, lactoskatone, ε -Decalactone, ε-dodecalactone, cyclohexyllactone, jasmine lacto , Cis-jasmone lactone, methyl γ- decalactone, and lactone having the following structure (R-1) and (R-2) (dotted lines. Shows the binding position), and the like.

  In addition, examples of the substituent of the cyclic organic group which may have a hetero atom include the same substituents as those of the above-described linear or branched monovalent hydrocarbon group having 1 to 30 carbon atoms. Can do.

  Examples of the cyclic organic group which may have a monovalent heteroatom having 4 to 30 carbon atoms substituted with such a substituent include a 2-bromofuryl group and a 3-methoxythienyl group.

  In this invention, it is preferable that the acid generator (A) which consists of a compound shown by the said General formula (1) consists of a compound shown by the following general formula (2).

〔一般式（２）において、Ｒ^３は相互に独立に、水素原子、フッ素原子、又は、水素原子の一部若しくは全てがフッ素原子で置換された炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基を示し、且つＲ^３のうち少なくとも１つは、フッ素原子、又は水素原子の一部若しくは全てがフッ素原子で置換された炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基を示す。Ｒ^４は相互に独立に、（ａ１）置換若しくは非置換の炭素数１〜３０の直鎖状若しくは分岐状の１価の炭化水素基、（ａ２）エステル結合、アミド結合、ウレタン結合及びスルフィド結合から選ばれる連結基を更に有する上記炭化水素基（ａ１）、（ａ３）置換若しくは非置換の炭素数３〜３０の環状若しくは環状構造を有する１価の脂肪族炭化水素基、（ａ４）エステル結合、アミド結合、ウレタン結合及びスルフィド結合から選ばれる連結基を更に有する上記炭化水素基（ａ３）、（ａ５）置換若しくは非置換の炭素数６〜３０のアリール基、又は、（ａ６）置換若しくは非置換の炭素数４〜３０の１価のヘテロ原子を有してもよい環状有機基を示す。Ｍ^＋は１価のオニウムカチオンを示す。〕

[In General Formula (2), R ³ is independently a hydrogen atom, a fluorine atom, or a linear or branched group having 1 to 30 carbon atoms in which some or all of the hydrogen atoms are substituted with fluorine atoms. And at least one of R ³ is a fluorine atom or a linear or branched group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms are substituted with fluorine atoms These are monovalent hydrocarbon groups. R ⁴ is independently of each other (a1) a substituted or unsubstituted C 1-30 linear or branched monovalent hydrocarbon group, (a2) an ester bond, an amide bond, a urethane bond and a sulfide bond. The hydrocarbon group (a1) further having a linking group selected from: (a3) a substituted or unsubstituted monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms, (a4) an ester bond The hydrocarbon group (a3) further having a linking group selected from an amide bond, a urethane bond and a sulfide bond, (a5) a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or (a6) a substituted or non-substituted group. The cyclic organic group which may have a C1-C30 monovalent | monohydric hetero atom of substitution is shown. M ⁺ represents a monovalent onium cation. ]

Examples of the linear or branched monovalent hydrocarbon group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms in R ³ of the general formula (2) are substituted with fluorine atoms include, for example, a methyl group, Ethyl group, n-propyl group, i-propyl group, n-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n- A group in which part or all of hydrogen atoms in a hydrocarbon group such as an octyl group, an i-octyl group, an n-nonyl group, an n-decyl group, a 2-ethylhexyl group, and an n-dodecyl group are substituted with a fluorine atom Can be mentioned.

For the groups [(a1) to (a6)] represented by R ⁴ in the general formula (2), (a1 in R ^a of the above general formulas (1-1a-1) and (1-1a-2) ) To (a6).

Specific examples of the compound represented by the general formula (1) or (2) include the following (A1) to (A15). Note that M ⁺ (monovalent onium cation) in each formula will be described later.

In addition, examples of the M ⁺ monovalent onium cation in each of the above general formulas include onium cations such as O, S, Se, N, P, As, Sb, Cl, Br, and I. Among these, the onium cations of S and I are preferable, and the onium cation of S is particularly preferable.

  Specific examples of the sulfonium cation (S onium cation) include those represented by the following general formula (m1). Specific examples of the iodonium cation (I onium cation) include those represented by the following general formula (m2).

〔一般式（ｍ１）において、Ｒ^１０１、Ｒ^１０２及びＲ^１０３は、相互に独立に、置換若しくは非置換の炭素数１〜１０の直鎖状若しくは分岐状のアルキル基、又は置換若しくは非置換の炭素数６〜１８のアリール基を示すか、或いは、Ｒ^１０１、Ｒ^１０２及びＲ^１０３のうちのいずれか２つが相互に結合して式中の硫黄原子と共に環状構造を形成しており、残りの１つが置換若しくは非置換の炭素数１〜１０の直鎖状若しくは分岐状のアルキル基、又は置換若しくは非置換の炭素数６〜１８のアリール基を示す。〕

[In General Formula (m1), R ¹⁰¹ , R ^102, and R ¹⁰³ are each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted group. An aryl group having 6 to 18 carbon atoms, or any two of R ¹⁰¹ , R ¹⁰² and R ¹⁰³ are bonded to each other to form a cyclic structure together with the sulfur atom in the formula, One represents a substituted or unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms. ]

〔一般式（ｍ２）において、Ｒ^１０４及びＲ^１０５は、相互に独立に、置換若しくは非置換の炭素数１〜１０の直鎖状若しくは分岐状のアルキル基、又は置換若しくは非置換の炭素数６〜１８のアリール基を示すか、或いは、Ｒ^１０４及びＲ^１０５が相互に結合して式中のヨウ素原子と共に環状構造を形成している。〕

[In General Formula (m2), R ¹⁰⁴ and R ¹⁰⁵ are each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted carbon number of 6; Or an aryl group of ˜18, or R ¹⁰⁴ and R ¹⁰⁵ are bonded to each other to form a cyclic structure together with an iodine atom in the formula. ]

Examples of the unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms in R ^{101 to} R ¹⁰³ of the general formula (m1) include, for example, a methyl group, an ethyl group, an n-propyl group, and an i-propyl group. N-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n-octyl group, i-octyl group, n-nonyl group , N-decyl group, and 2-ethylhexyl group.
In addition, this alkyl group includes halogen atoms such as fluorine, chlorine, bromine and iodine, hydroxy groups, thiol groups, and hetero atoms (for example, halogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, phosphorus atoms, silicon atoms, etc.) ) May be substituted with a substituent such as an organic group.

Examples of the unsubstituted aryl group having 6 to 18 carbon atoms in R ^{101 to} R ¹⁰³ of the general formula (m1) include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, and 1-phenanthryl. Groups and the like.
In addition, the aryl group includes a halogen atom such as fluorine, chlorine, bromine, iodine, a hydroxy group, a thiol group, an alkyl group, an alkoxy group, and a hetero atom (for example, a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom). Atoms, silicon atoms, etc.) may be substituted with a substituent such as an organic group.

  Among the onium cations represented by the general formula (m1), an onium cation represented by the following general formula (m1-1) or (m1-2) is preferable, and particularly represented by the general formula (m1-1). Onium cations are preferred.

In General Formula (m1-1), R ^{111 to} R ¹¹³ each independently represent a hydroxy group, a halogen atom, an alkyl group that may have a substituent, a cycloalkyl group, an alkoxy group, or —S—R ^114. Group (R ¹¹⁴ represents an alkyl group which may have a substituent or an aryl group), or —SO ₂ —R ¹¹⁵ group (R ¹¹⁵ is an alkyl group which may have a substituent). Represents a cycloalkyl group, an alkoxy group, or an aryl group. However, at least one of R ¹¹¹ is a —SO ₂ —R ¹¹⁵ group. l is an integer of 1-5. m is an integer of 0-5. n is an integer of 0-5.

In General Formula (m1-2), R ¹²¹ represents a substituted or unsubstituted linear or branched alkyl group having 1 to 8 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 8 carbon atoms. Alternatively, two or more R ¹²¹ are bonded to each other to form a ring. However, when a plurality of R ¹²¹ are present, they may be the same or different.
R ¹²² represents a substituted or unsubstituted linear or branched alkyl group having 1 to 7 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 7 carbon atoms, or two or more R ¹²² are bonded to each other to form a ring. However, when a plurality of R ¹²² are present, they may be the same or different.
o represents an integer of 0 to 7, p represents an integer of 0 to 6, and q represents an integer of 0 to 3.

As a halogen atom in R < ¹¹¹ > -R < ¹¹³ > of general formula (m1-1), a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned.
Examples of the alkyl group in R ^{111 to} R ¹¹³ include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a 2-methylpropyl group, a 1-methylpropyl group, and a t-butyl group. Groups and the like. Among these, those having 1 to 4 carbon atoms are preferable.
Examples of the cycloalkyl group in R ^{111 to} R ¹¹³ include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Among these, those having 5 to 6 carbon atoms are preferable.
Examples of the alkoxy group in R ^{111 to} R ¹¹³ include a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, a 2-methylpropoxy group, a 1-methylpropoxy group, and t-butoxy. Groups and the like. Among these, those having 1 to 4 carbon atoms are preferable.
One or more hydrogen atoms in each of the alkyl group, cycloalkyl group and alkoxy group may be substituted. Specific examples of the substituent include a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), phenyl group, acetoxy group, alkyl group, alkoxy group and the like.

Examples of the alkyl group of R ¹¹⁴ in the —S—R ¹¹⁴ group of R ^{111 to} R ¹¹³ include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, and a 2-methylpropyl group. , 1-methylpropyl group, t-butyl group and the like.
Examples of the aryl group for R ¹¹⁴ include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, and a 1-phenanthryl group. Among these, those having 6 to 12 carbon atoms are preferable.
In addition, one or more hydrogen atoms in each of the alkyl group and aryl group of R ¹¹⁴ may be substituted with the above-described substituent.

As the alkyl group, cycloalkyl group, alkoxy group and aryl group optionally having a substituent of R ¹¹⁵ in the —SO ₂ —R ¹¹⁵ group of R ^{111 to} R ¹¹³ , the above R ^{111 to} R ¹¹⁴ are used. You can list what you explained.
Specific examples of the —SO ₂ —R ¹¹⁵ group include groups having structures represented by the following formulas (h1) to (h8). Among these, groups represented by (h1) and (h2) are preferable.

Examples of the unsubstituted linear or branched alkyl group having 1 to 8 carbon atoms in R ¹²¹ of the general formula (m1-2) include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, n-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n-octyl group, i-octyl group, and 2-ethylhexyl group Etc.
In addition, this alkyl group includes halogen atoms such as fluorine, chlorine, bromine and iodine, hydroxy groups, thiol groups, and hetero atoms (for example, halogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, phosphorus atoms, silicon atoms, etc.) ) May be substituted with a substituent such as an organic group.

Examples of the unsubstituted aryl group having 6 to 8 carbon atoms in R ¹²¹ include a phenyl group.
In addition, this aryl group includes a halogen atom such as fluorine, chlorine, bromine and iodine, a hydroxy group, a thiol group, an alkyl group, and a hetero atom (for example, a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, It may be substituted with a substituent such as an organic group containing a silicon atom).

Examples of the unsubstituted linear or branched alkyl group having 1 to 7 carbon atoms in R ¹²² of the general formula (m1-2) include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, Examples thereof include an n-butyl group, a t-butyl group, an n-pentyl group, an i-pentyl group, an n-hexyl group, an i-hexyl group, and an n-heptyl group.
In addition, this alkyl group includes halogen atoms such as fluorine, chlorine, bromine and iodine, hydroxy groups, thiol groups, and hetero atoms (for example, halogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, phosphorus atoms, silicon atoms, etc.) ) May be substituted with a substituent such as an organic group.

Examples of the unsubstituted aryl group having 6 to 7 carbon atoms for R ¹²² include a phenyl group.
In addition, this aryl group includes a halogen atom such as fluorine, chlorine, bromine and iodine, a hydroxy group, a thiol group, an alkyl group, and a hetero atom (for example, a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, It may be substituted with a substituent such as an organic group containing a silicon atom).

  Among the sulfonium cations represented by the general formula (m1), those represented by the following formulas (i-1) to (i-13) are preferable.

Examples of the unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms in R ¹⁰⁴ and R ¹⁰⁵ of the general formula (m2) include, for example, a methyl group, an ethyl group, an n-propyl group, and an i-propyl group. N-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n-octyl group, i-octyl group, n-nonyl group , N-decyl group, and 2-ethylhexyl group.
In addition, this alkyl group includes halogen atoms such as fluorine, chlorine, bromine and iodine, hydroxy groups, thiol groups, and hetero atoms (for example, halogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, phosphorus atoms, silicon atoms, etc.) ) May be substituted with a substituent such as an organic group.

Examples of the unsubstituted aryl group having 6 to 18 carbon atoms in R ¹⁰⁴ and R ¹⁰⁵ of the general formula (m2) include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, and 1-phenanthryl. Groups and the like.
In addition, this aryl group includes a halogen atom such as fluorine, chlorine, bromine and iodine, a hydroxy group, a thiol group, an alkyl group, and a hetero atom (for example, a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, It may be substituted with a substituent such as an organic group containing a silicon atom).

  Among the onium cations represented by the general formula (m2), an onium cation represented by the following general formula (m2-1) is preferable.

In General Formula (m2-1), R ¹³¹ and R ¹³² are each independently a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, or a substituted or unsubstituted group. Or an aryl group having 6 to 12 carbon atoms, or two or more of R ¹³¹ and R ¹³² are bonded to each other to form a ring. However, when a plurality of R ¹³¹ and R ¹³² are present, they may be the same or different.
r represents an integer of 0 to 5, and s represents an integer of 0 to 5.

Examples of the unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms in R ¹³¹ and R ¹³² of the general formula (m2-1) include, for example, a methyl group, an ethyl group, an n-propyl group, i- Examples include propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like.
In addition, this alkyl group includes halogen atoms such as fluorine, chlorine, bromine and iodine, hydroxy groups, thiol groups, and hetero atoms (for example, halogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, phosphorus atoms, silicon atoms, etc.) ) May be substituted with a substituent such as an organic group.

Examples of the unsubstituted aryl group having 6 to 12 carbon atoms in R ¹³¹ and R ¹³² include a phenyl group and a naphthyl group.
In addition, this aryl group includes a halogen atom such as fluorine, chlorine, bromine and iodine, a hydroxy group, a thiol group, an alkyl group, and a hetero atom (for example, a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, It may be substituted with a substituent such as an organic group containing a silicon atom).

  Among the iodonium cations represented by the general formula (m2), those represented by the following formulas (ii-1) to (ii-3) are preferable.

  Among the monovalent onium cations described above, in particular, the sulfonium cation represented by the above formulas (i-1) and (i-6) to (i-13), the above formula (ii-1) or ( The iodonium cation represented by ii-2) is preferred.

The monovalent onium cation represented by M ⁺ in the acid generator (A) is described in, for example, Advances in Polymer Science, Vol. 62, p. It can be produced according to the general method described in 1-48 (1984).

In addition, the acid generator (A) contained in the radiation-sensitive composition of the present invention generates an acid by dissociation of a monovalent onium cation (M ⁺ ) triggered by exposure or heating. Specifically, the sulfonic acid represented by the following general formula (1a) is generated, and the sulfonic acid represented by the following general formula (2a) is preferably generated.

R ¹ and R ² in the general formula (1a) are respectively synonymous with R ¹ and R ² in the general formula (1), and the above descriptions can be applied as they are.
Also, ^{R 3} and ^{R 4} in the general formula (2a), respectively, have the same meanings as ^{R 3} and ^{R 4} in the general formula (2), can be directly applied to the corresponding sections above.

Further, the method for synthesizing such an acid generator (A) is not particularly limited. For example, as represented by the following reaction formulas, the compounds represented by the general formulas (X1) and (X2) It can be synthesized by reacting a desired onium cation (M ⁺ ) halide (for example, M ⁺ Br ⁻ ) in an aqueous solution.

^R 1 to R ⁴ and ^{M +} is used in the above reaction formula, respectively, the general formula (1) and (2) have the same meanings as those ^R 1 to R ⁴ and ^{M +} at, can be directly applied to the corresponding sections above .

  In addition, the radiation sensitive composition of this invention may contain only 1 type of the above-mentioned acid generator (A), and may contain 2 or more types.

  The content of the acid generator (A) in the radiation-sensitive composition of the present invention is usually 0.1 to 50 parts by mass with respect to a total of 100 parts by mass of the resin (B) and acid-decomposable dissolution inhibiting compound described later. The amount is preferably 1 to 40 parts by mass, more preferably 5 to 30 parts by mass. When content of an acid generator (A) is less than 0.1 mass part, there exists a possibility that the effect of this invention may not fully be expressed. On the other hand, when it exceeds 50 parts by mass, there is a possibility that transparency to radiation, pattern shape, heat resistance and the like may be lowered.

[1-2] Resin (B)
Moreover, the radiation-sensitive composition of the present invention may further contain a resin.
The resin (hereinafter also referred to as “resin (B)”) is a resin that is alkali-insoluble or hardly alkali-soluble containing a repeating unit having an acid-dissociable group, and is easily alkali-soluble by the action of an acid. . Here, in the present specification, “alkali insoluble or alkali insoluble” means an alkali development condition employed when a resist pattern is formed from a resist film formed from a radiation-sensitive composition containing the resin (B). Below, when a 100 nm-thick film using only the resin (B) is developed instead of the resist film, it means that 50% or more of the initial film thickness of the resist film remains after development.

  When the radiation-sensitive composition of the present invention contains such a resin (B), it is sensitive to an electron beam or extreme ultraviolet rays in a lithography process, and a fine pattern can be stably obtained with high accuracy. A chemically amplified positive resist film that can be formed is preferable because it can be formed.

The repeating unit having an acid dissociable group contained in the resin (B) is one in which the acid dissociable group is dissociated by the action of an acid. Although this repeating unit is not specifically limited as long as it has the above-mentioned action, the repeating unit represented by the following general formula (p-1) (hereinafter referred to as “repeating unit (p-1)”), and And at least one of repeating units represented by the following general formula (p-2) (hereinafter referred to as “repeating unit (p-2)”).
By using at least one of the repeating units (p-1) and (p-2) as the repeating unit having such an acid dissociable group, there is an advantage that good sensitivity can be obtained.

〔一般式（ｐ−１）において、Ｒ^２１は、水素原子、メチル基、トリフルオロメチル基又はヒドロキシメチル基を示す。Ｒ^２２は、相互に独立に、炭素数１〜４の直鎖状若しくは分岐状のアルキル基、炭素数６〜２２のアリール基、又は炭素数４〜２０の１価の脂環式炭化水素基若しくはそれから誘導される基を示すか、或いは、いずれか２つのＲ^２２が相互に結合して、それぞれが結合している炭素原子とともに２価の脂環式炭化水素基若しくはそれから誘導される基を形成し、残りの１つのＲ^２２が、炭素数１〜４の直鎖状若しくは分岐状のアルキル基、炭素数６〜２２のアリール基、又は炭素数４〜２０の１価の脂環式炭化水素基若しくはそれから誘導される基を示す。〕

[In General Formula (p-1), R ²¹ represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group. R ²² is independently of each other a linear or branched alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 22 carbon atoms, or a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms. Or a group derived therefrom, or any two R ²² 's bonded to each other to form a divalent alicyclic hydrocarbon group or a group derived therefrom together with the carbon atom to which each is bonded. And the remaining one R ²² is a linear or branched alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 22 carbon atoms, or a monovalent alicyclic carbonization having 4 to 20 carbon atoms. A hydrogen group or a group derived therefrom is shown. ]

〔一般式（ｐ−２）において、Ｒ^２３は、水素原子、メチル基、トリフルオロメチル基又はヒドロキシメチル基を示す。Ｒ^２４は、相互に独立に、炭素数１〜４の直鎖状若しくは分岐状のアルキル基、又は炭素数４〜２０の１価の脂環式炭化水素基若しくはそれから誘導される基を示すか、或いは、いずれか２つのＲ^２４が相互に結合して、それぞれが結合している炭素原子とともに２価の脂環式炭化水素基若しくはそれから誘導される基を形成し、残りの１つのＲ^２４が、炭素数１〜４の直鎖状若しくは分岐状のアルキル基、又は炭素数４〜２０の１価の脂環式炭化水素基若しくはそれから誘導される基を示す。〕

[In General Formula (p-2), R ²³ represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group. Does R ²⁴ each independently represent a linear or branched alkyl group having 1 to 4 carbon atoms, or a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms or a group derived therefrom? Alternatively, any two R ²⁴ are bonded to each other to form a divalent alicyclic hydrocarbon group or a group derived therefrom together with the carbon atom to which each is bonded, and the remaining one R ²⁴ Represents a linear or branched alkyl group having 1 to 4 carbon atoms, a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms, or a group derived therefrom. ]

Examples of the linear or branched alkyl group having 1 to 4 carbon atoms in R ²² of the general formula (p-1) include, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n- A butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like can be mentioned.

Examples of the monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms in R ²² of the general formula (p-1) include norbornane, tricyclodecane, tetracyclododecane, adamantane, cyclobutane, cyclopentane, and cyclohexane. , Groups composed of alicyclic rings derived from cycloalkanes such as cycloheptane and cyclooctane.
Examples of the group derived from this alicyclic hydrocarbon group include the above-mentioned monovalent alicyclic hydrocarbon groups such as methyl group, ethyl group, n-propyl group, i-propyl group, n- A group substituted by one or more of linear, branched or cyclic alkyl groups having 1 to 4 carbon atoms such as butyl group, 2-methylpropyl group, 1-methylpropyl group and t-butyl group. Etc.

Examples of the aryl group having 6 to ²² carbon atoms in R ²² of the general formula (p-1) include groups derived from structures such as the following (x-1) to (x-3). In addition, when R ²² is a group derived from the following (x-2) (that is, a naphthyl group), the carbon atom in the [—O—C (R ²² ) ₃ ] portion of the general formula (p-1) The bonding position bonded to (the carbon atom bonded to the oxygen atom) may be either the 1-position or the 2-position. In addition, when R ²² is a group derived from the following (x-3) (that is, an anthryl group), the carbon atom in the [—O—C (R ²² ) ₃ ] portion of the general formula (p-1) The bonding position for bonding to 1 may be any of the 1st, 2nd and 9th positions.
The aryl group may be substituted. Specific examples of the substituent include, for example, methyl group, ethyl group, hydroxy group, carboxyl group, halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group) Etc.), alkyloxycarbonyl groups and the like.

In addition, as the divalent alicyclic hydrocarbon group formed together with any two R ²² bonded to each other and the carbon atom to which each R ²² is bonded (the carbon atom bonded to the oxygen atom), A bivalent alicyclic hydrocarbon group of several 4-20 is mentioned. Specific examples include groups composed of alicyclic rings derived from norbornane, tricyclodecane, tetracyclododecane, adamantane, cyclopentane, cyclohexane and the like.
Further, examples of the group derived from a divalent alicyclic hydrocarbon group formed by bonding R ²² to each other include the above-described divalent alicyclic hydrocarbon group such as a methyl group, an ethyl group, and the like. , N-propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, etc., linear, branched or cyclic alkyl having 1 to 4 carbon atoms Examples include groups substituted with one or more groups or one or more groups.

  Among the repeating units (p-1), repeating units represented by the following general formulas (p-1-1) to (p-1-7) are preferable, and the following general formulas (p-1-2), ( The repeating unit represented by p-1-3) or (p-1-4) is more preferable. When the resin (B) contains these repeating units, an excellent resist pattern can be formed by nano edge roughness.

〔一般式（ｐ−１−１）〜（ｐ−１−７）において、Ｒ^２１は、水素原子、メチル基、トリフルオロメチル基又はヒドロキシメチル基を示す。Ｒ^２５は、相互に独立に、炭素数１〜４の直鎖状若しくは分岐状のアルキル基、又は炭素数６〜２２のアリール基を示す。〕

[In General Formulas (p-1-1) to (p-1-7), R ²¹ represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group. R ²⁵ independently represents a linear or branched alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 22 carbon atoms. ]

About “C1-C4 linear or branched alkyl group” and “C6-C22 aryl group” in R ²⁵ of formulas (p-1-1) to (p-1-7) Respectively apply the description of “a linear or branched alkyl group having 1 to 4 carbon atoms” and “aryl group having 6 to 22 carbon atoms” in R ²² of the general formula (p-1). be able to.

  In addition, resin (B) may contain 1 type of repeating units (p-1), and may contain 2 or more types.

In addition, in R ²⁴ of the general formula (p-2), “a linear or branched alkyl group having 1 to 4 carbon atoms”, “a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms, or Regarding the “derived group” and “a divalent alicyclic hydrocarbon group or a group derived therefrom together with any two R ²⁴ bonded to each other and the carbon atom to which each is bonded”, “A linear or branched alkyl group having 1 to 4 carbon atoms”, “a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms” or a derivative thereof in R ²² of the general formula (p-1). And the description of “a group that is divalent alicyclic hydrocarbon group or a group derived therefrom” together with the carbon atom to which any two of R ²² are bonded to each other. Can do.

  Among the repeating units (p-2), a repeating unit represented by the following general formula (p-2-1) is preferable. When the resin (B) contains these repeating units, an excellent resist pattern can be formed by nano edge roughness.

〔一般式（ｐ−２−１）において、Ｒ^２３は、水素原子、メチル基、トリフルオロメチル基又はヒドロキシメチル基を示す。Ｒ^２６は、相互に独立に、炭素数１〜４の直鎖状若しくは分岐状のアルキル基を示す。〕

[In General Formula (p-2-1), R ²³ represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group. R ²⁶ independently represents a linear or branched alkyl group having 1 to 4 carbon atoms. ]

The “linear or branched alkyl group having 1 to 4 carbon atoms” in R ²⁶ of the general formula (p-2-1) is the same as “the number of carbon atoms of 1 to 4 in R ²² of the general formula (p-1)”. The description of “4 linear or branched alkyl group” can be applied as it is.

  In addition, resin (B) may contain 1 type of repeating units (p-2), and may contain 2 or more types.

  In addition, the resin (B) in the present invention includes, in addition to the repeating units (p-1) and (p-2), repeating units represented by the following general formulas (b-1) to (b-5). It is preferable to contain at least one of them.

〔一般式（ｂ−１）において、Ｒ^１１は、水素原子又はメチル基を示す。Ｒ^１２は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシ基を示す。ｋは０〜３の整数を示し、ｌは０〜３の整数を示し、且つｋ＋ｌ≦５を満たす。〕

[In General Formula (b-1), R ¹¹ represents a hydrogen atom or a methyl group. R ¹² represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. k represents an integer of 0 to 3, l represents an integer of 0 to 3, and k + l ≦ 5 is satisfied. ]

〔一般式（ｂ−２）において、Ｒ^１３は、水素原子又はメチル基を示す。Ｒ^１４は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシ基を示す。ｍは０〜３の整数を示し、ｎは０〜３の整数を示し、且つｍ＋ｎ≦５を満たす。〕

[In General Formula (b-2), R ¹³ represents a hydrogen atom or a methyl group. R ¹⁴ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. m represents an integer of 0 to 3, n represents an integer of 0 to 3, and satisfies m + n ≦ 5. ]

〔一般式（ｂ−３）において、Ｒ^１５は、水素原子又はメチル基を示す。Ｒ^１６は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシ基を示す。ｐは０〜３の整数を示し、ｑは０〜３の整数を示し、且つｐ＋ｑ≦５を満たす。〕

[In General Formula (b-3), R ¹⁵ represents a hydrogen atom or a methyl group. R ¹⁶ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. p represents an integer of 0 to 3, q represents an integer of 0 to 3, and satisfies p + q ≦ 5. ]

〔一般式（ｂ−４）において、Ｒ^１７は、水素原子又はメチル基を示す。Ｒ^１８は、炭素数１〜１２の直鎖状若しくは分岐状のアルキル基、又は、炭素数１〜１２の直鎖状若しくは分岐状のアルコキシ基を示す。ｒは０〜３の整数を示し、ｓは０〜３の整数を示す。〕

[In General Formula (b-4), R ¹⁷ represents a hydrogen atom or a methyl group. R ¹⁸ represents a linear or branched alkyl group having 1 to 12 carbon atoms or a linear or branched alkoxy group having 1 to 12 carbon atoms. r represents an integer of 0 to 3, and s represents an integer of 0 to 3. ]

〔一般式（ｂ−５）において、Ｒ^１９は、水素原子又はメチル基を示す。〕

[In General Formula (b-5), R ¹⁹ represents a hydrogen atom or a methyl group. ]

  When the resin (B) in the present invention contains a repeating unit represented by the general formula (b-1) (hereinafter referred to as “repeating unit (b-1)”), the resist pattern is excellent in nano edge roughness. Can be formed.

Examples of the linear or branched alkyl group having 1 to 12 carbon atoms in R ¹² of the general formula (b-1) include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, and n-butyl. Group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like. Among these, a methyl group, an ethyl group, an n-butyl group, and a t-butyl group are preferable because of excellent nano edge roughness.

Examples of the linear or branched alkoxy group having 1 to 12 carbon atoms in R ¹² of the general formula (b-1) include a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, and n-butoxy. Group, 2-methylpropoxy group, 1-methylpropoxy group, t-butoxy group and the like. Among these, a methoxy group and an ethoxy group are preferable because of excellent nano edge roughness.

  K in the general formula (b-1) is an integer of 0 to 3, and preferably 1 or 2. Moreover, l is an integer of 0-3, and it is preferable that it is an integer of 0-2.

Specific examples of the repeating unit (b-1) include repeating units represented by the following formulas (b-1-1) to (b-1-4).
Note that the repeating unit (b-1) may be included in the resin (B) only in one kind, or in two or more kinds.

  The repeating unit (b-1) can be obtained by using the corresponding hydroxystyrene derivative as a monomer. Moreover, it can also obtain by using as a monomer the compound from which a hydroxy styrene derivative is obtained by hydrolyzing.

  Examples of the monomer used for generating the repeating unit (b-1) include p-acetoxystyrene, p- (1-ethoxy) styrene, p-isopropenylphenol and the like. In addition, when p-acetoxystyrene is used, a repeating unit (b-1) is produced | generated by performing a hydrolysis reaction of a side chain after a polymerization reaction.

  When the resin (B) in the present invention contains a repeating unit represented by the general formula (b-2) (hereinafter referred to as “repeating unit (b-2)”), the resist pattern is excellent in nano edge roughness. Can be formed.

Examples of the linear or branched alkyl group having 1 to 12 carbon atoms and the linear or branched alkoxy group having 1 to 12 carbon atoms in R ¹⁴ of the general formula (b-2) have been described above. Examples thereof are the same as the linear or branched alkyl group having 1 to 12 carbon atoms and the linear or branched alkoxy group having 1 to 12 carbon atoms in R ¹² of the general formula (b-1). be able to.

  M in the general formula (b-2) is an integer of 0 to 3, and is preferably 0 or 1. N is an integer of 0 to 3, and is preferably 1 or 2.

Specific examples of the repeating unit (b-2) include repeating units represented by the following formulas (b-2-1) and (b-2-2).
Note that the repeating unit (b-2) may be included in the resin (B) only in one kind, or in two or more kinds.

The repeating unit (b-2) can be obtained by using a corresponding monomer.
As a monomer used in order to produce | generate this repeating unit (b-2), 4-hydroxyphenyl acrylate, 4-hydroxyphenyl methacrylate, etc. are mentioned, for example.

  When the resin (B) in the present invention contains a repeating unit represented by the general formula (b-3) (hereinafter referred to as “repeating unit (b-3)”), the resist pattern is excellent in nano edge roughness. Can be formed.

Examples of the linear or branched alkyl group having 1 to 12 carbon atoms and the linear or branched alkoxy group having 1 to 12 carbon atoms in R ¹⁶ of the general formula (b-3) have been described above. Examples thereof are the same as the linear or branched alkyl group having 1 to 12 carbon atoms and the linear or branched alkoxy group having 1 to 12 carbon atoms in R ¹² of the general formula (b-1). be able to.

  P in the general formula (b-3) is an integer of 0 to 3, and preferably 1 or 2. Q is an integer of 0 to 3, and is preferably 0 or 1.

Specific examples of the repeating unit (b-3) include repeating units represented by the following formulas (b-3-1) and (b-3-2).
In addition, 1 type of repeating units (b-3) may be contained in resin (B), and may be contained 2 or more types.

The repeating unit (b-3) can be obtained by using a corresponding monomer.
As a monomer used in order to produce | generate this repeating unit (b-3), N- (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide, etc. are mentioned, for example.

  When the resin (B) in the present invention contains a repeating unit represented by the general formula (b-4) (hereinafter referred to as “repeating unit (b-4)”), the resist pattern is excellent in nano edge roughness. Can be formed.

Examples of the linear or branched alkyl group having 1 to 12 carbon atoms and the linear or branched alkoxy group having 1 to 12 carbon atoms in R ¹⁸ of the general formula (b-4) have been described above. Examples thereof are the same as the linear or branched alkyl group having 1 to 12 carbon atoms and the linear or branched alkoxy group having 1 to 12 carbon atoms in R ¹² of the general formula (b-1). be able to.

  R in the general formula (b-4) is an integer of 0 to 3, and preferably 1 or 2. S is an integer of 0 to 3, and is preferably 0 or 1.

Specific examples of the repeating unit (b-4) include repeating units represented by the following formulas (b-4-1) and (b-4-2).
In addition, the repeating unit (b-4) may be included in the resin (B) only in one kind, or in two or more kinds.

The repeating unit (b-4) can be obtained by using a corresponding monomer.
Examples of the monomer used for generating the repeating unit (b-4) include 5-hydroxynaphthalen-1-yl methacrylate and 5-hydroxynaphthalen-1-yl acrylate.

  When the resin (B) in the present invention contains a repeating unit represented by the general formula (b-5) (hereinafter referred to as “repeating unit (b-5)”), a resist pattern excellent in nano edge roughness Can be formed.

Specific examples of the repeating unit (b-5) include repeating units represented by the following formulas (b-5-1) and (b-5-2).
In addition, 1 type of repeating units (b-5) may be contained in resin (B), and may be contained 2 or more types.

The repeating unit (b-5) can be obtained by using a corresponding monomer.
As a monomer used in order to produce this repeating unit (b-5), for example, a compound represented by the following general formula (M-5-1) or the following general formula (M-5-2) Is mentioned.

The resin (B) is a non-acid dissociable compound [the action of acid] in addition to the repeating units (p-1) and (p-2) and the repeating units (b-1) to (b-5) described above. May further contain a repeating unit derived from a compound that does not contain a group (acid-dissociable group) dissociated by (hereinafter referred to as “repeating unit (b-6)”).
When the resin (B) in the present invention contains the repeating unit (b-6), an excellent resist pattern can be formed by nano edge roughness.

Examples of the non-acid dissociable compound for generating the repeating unit (b-6) include styrene, α-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene, isobornyl acrylate, Examples include cyclodecanyl (meth) acrylate and tetracyclododecenyl (meth) acrylate. Among these, styrene, α-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene, and tricyclodecanyl acrylate are preferable.
In addition, 1 type of repeating units (b-6) may be contained in resin (B), and may be contained 2 or more types.

  The content ratio of the repeating unit having an acid dissociable group in the resin (B) [particularly, the total content ratio of the repeating units (p-1) and (p-2)] is the number of all the repeating units included in the resin (B). When the total of the units is 100 mol%, it is preferably 1 mol% or more, more preferably 10 to 70 mol%, still more preferably 20 to 60 mol%. When this content rate is less than 1 mol%, nano edge roughness may be deteriorated. In addition, when this content rate is 1 mol% or more (especially 10-70 mol%), the resist film which exhibits the outstanding nano edge roughness can be formed.

  The total content of the repeating units (b-1) to (b-5) in the resin (B) is 95 mol% when the total of all repeating units contained in the resin (B) is 100 mol%. The content is preferably 1 to 95 mol%, more preferably 10 to 95 mol%, and particularly preferably 40 to 80 mol%. When this content rate exceeds 95 mol%, there exists a possibility that nano edge roughness may deteriorate. In addition, when this content rate is 1 mol% or more, the resist film excellent in nano edge roughness can be formed.

  The total content of the repeating units (p-1), (p-2), and (b-1) to (b-5) in the resin (B) is the same as that of all the repeating units included in the resin (B). When the total is 100 mol%, it is preferably 10 mol% or more, more preferably 40 to 100 mol%, still more preferably 50 to 100 mol%. When this content rate is less than 10 mol%, there exists a possibility that nano edge roughness may deteriorate. In addition, when this content rate is 10 mol% or more, the resist film which exhibits the outstanding nano edge roughness can be formed.

  The content ratio of the repeating unit (b-6) in the resin (B) is preferably 60 mol% or less when the total of all the repeating units contained in the resin (B) is 100 mol%. Preferably it is 0-50 mol%. When this content rate exceeds 60 mol%, there exists a possibility that nano edge roughness may deteriorate. Moreover, when it is 60 mol% or less, the resist film excellent in the balance of the performance of resolution performance and nanoedge roughness can be formed.

  The method for synthesizing the resin (B) is not particularly limited, and can be obtained by, for example, known radical polymerization or anionic polymerization. Further, the side chain phenol moiety or naphthol moiety in the above-mentioned repeating units (b-1) to (b-4) is the acetoxy group in the presence of a base or acid in an organic solvent in the presence of a base or acid. Can be obtained by hydrolysis.

The polystyrene equivalent weight average molecular weight (hereinafter also referred to as “Mw”) of the resin (B) measured by gel permeation chromatography (GPC) is preferably 3000 to 100,000, more preferably 3000 to 40000, More preferably, it is 3000-25000.
Further, the ratio (Mw / Mn) of the Mw of the resin (B) and the polystyrene-equivalent number average molecular weight (hereinafter also referred to as “Mn”) measured by GPC is preferably 1 to 5, more preferably. Is 1 to 3, more preferably 1 to 2.5.

  In addition, the radiation sensitive composition of this invention may contain only 1 type of the above-mentioned resin (B), and may contain 2 or more types.

[1-3] Acid-decomposable dissolution inhibiting compound The radiation-sensitive composition of the present invention may further contain an acid-decomposable dissolution inhibiting compound.
The acid-decomposable dissolution inhibiting compound is a compound having at least two groups (acid-decomposable groups) that can be decomposed by an acid in its structure.
As the acid-decomposable dissolution inhibiting compound, JP-A-1-289946, JP-A-1-289947, JP-A-2-2560, JP-A-3-128959, JP-A-3-158855, JP-A-3 JP-A-3-179353, JP-A-3-191351, JP-A-3-200251, JP-A-3-2000025, JP-A-3-200233, JP-A-3-200454, JP-A-3-200355, JP-A-3-22035. No. 259149, JP-A-3-279958, JP-A-3-279959, JP-A-4-1650, JP-A-4-1651, JP-A-4-11260, JP-A-4-12356, JP-A-4-12357. JP-A-4-271349, JP-A-5-045869, JP-A-5-158233, JP-A-5-224409, JP-A-5-257. No. 75, JP-A-5-297581, JP-A-5-297583, JP-A-5-303197, JP-A-05-303200, JP-A-5-341510, etc. And compounds in which a part or all of the functional OH group is protected with an acid-decomposable group (acid-decomposable group).

  Furthermore, examples of the acid-decomposable dissolution inhibiting compound include compounds described in the specification of JP2009-222920A.

[1-4] Acid Diffusion Control Agent The radiation-sensitive composition of the present invention is an acid diffusion control agent (hereinafter referred to as “acid”) except for the acid generator (A), resin (B) and acid-decomposable dissolution inhibiting compound. It is preferable to further contain a “diffusion control agent (C)”.
This acid diffusion controller (C) has a function of controlling the diffusion phenomenon in the resist film of the acid generated from the acid generator (A) by exposure and suppressing undesirable chemical reactions in the non-exposed areas. .

  By containing such an acid diffusion controller (C), the storage stability of the resulting radiation-sensitive composition is improved. In addition, the resolution of the formed resist film is further improved, and changes in the line width of the resist pattern due to fluctuations in the holding time (PED) from after exposure to post-exposure heat treatment can be suppressed, resulting in process stability. A radiation-sensitive composition that is extremely excellent in the above can be obtained.

Examples of the acid diffusion controller (C) include nitrogen-containing organic compounds and photosensitive basic compounds.
Examples of the nitrogen-containing organic compound include a compound represented by the following general formula (4) (hereinafter referred to as “nitrogen-containing compound (i)”), a compound having two nitrogen atoms in the same molecule (hereinafter referred to as “ Nitrogen-containing compound (ii) ”), polyamino compounds and polymers having three or more nitrogen atoms (hereinafter collectively referred to as“ nitrogen-containing compound (iii) ”), amide group-containing compounds, urea compounds, nitrogen-containing compounds And heterocyclic compounds.

In the general formula (4), each R ⁴¹ is independently of each other a hydrogen atom, an optionally substituted linear, branched or cyclic alkyl group, an optionally substituted aryl group, or a substituted group. An aralkyl group which may be present.

  Examples of the nitrogen-containing compound (i) include aromatic compounds in addition to mono (cyclo) alkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine and cyclohexylamine. Examples include amines.

  Examples of the nitrogen-containing compound (ii) include compounds having two nitrogen atoms in the same molecule, such as diamines and imidazolidinones.

  Examples of the nitrogen-containing compound (iii) include polyethyleneimine, polyallylamine, 2-dimethylaminoethylacrylamide polymer, and the like.

  Examples of the amide group-containing compound include Nt-butoxycarbonyl group-containing amino compounds, formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, Examples include propionamide, benzamide, pyrrolidone, N-methylpyrrolidone, N-acetyl-1-adamantylamine, and isocyanuric acid tris (2-hydroxyethyl).

  Examples of urea compounds include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tri-n-butylthiourea. Etc.

  Examples of the nitrogen-containing heterocyclic compound include imidazoles, pyridines and piperazines, as well as pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, piperidineethanol, 3-piperidino-1,2-propanediol and morpholine. 4-methylmorpholine, 1- (4-morpholinyl) ethanol, 4-acetylmorpholine, 3- (N-morpholino) -1,2-propanediol, 1,4-dimethylpiperazine, 1,4-diazabicyclo [2. 2.2] octane and the like.

  Although it does not specifically limit as said photosensitive basic compound as long as it has the above-mentioned property, For example, the compound etc. which are represented with the following general formula (5-1) or (5-2) are mentioned.

In the general formula (5-1), R ^{51 to} R ⁵³ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alicyclic carbonization. A hydrogen group, —OSO ₂ —R ⁵⁶ group, or —SO ₂ —R ⁵⁷ group (provided that R ⁵⁶ and R ⁵⁷ are each independently a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, A substituted or unsubstituted alicyclic hydrocarbon group, or a substituted or unsubstituted aryl group. Two or more of R ^{51 to} R ⁵³ may be bonded to each other to form a cyclic structure. A ⁻ represents OH ⁻ , R ⁵⁸ O ⁻ , or R ⁵⁸ COO ⁻ (wherein R ⁵⁸ represents a monovalent organic group).
In General Formula (5-2), R ⁵⁴ and R ⁵⁵ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted group. An alicyclic hydrocarbon group is shown. A ^{- is, OH -, R 59 O -} , or ^R 59 COO ^- showing the ^{(where, R 59} is a monovalent organic group.).

As a halogen atom in R < ⁵¹ > -R < ⁵³ > of General formula (5-1), a fluorine atom, a bromine atom, etc. are mentioned, for example.
Examples of the unsubstituted alkyl group having 1 to 10 carbon atoms in R ^{51 to} R ⁵⁷ in the general formulas (5-1) and (5-2) include a methyl group, an ethyl group, an n-propyl group, and i-propyl. Group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like.
In addition, this alkyl group includes a hydroxy group, a carboxyl group, a halogen atom (fluorine atom, bromine atom, etc.), an alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group, t-butoxy group, etc.), alkyloxycarbonyl group. It may be substituted with a substituent such as (t-butoxycarbonylmethyloxy group and the like).

Examples of the unsubstituted alicyclic hydrocarbon group in R ^{51 to} R ⁵⁷ include an alicyclic hydrocarbon group having 5 to 25 carbon atoms. Specifically, a cyclopentyl group, a cyclohexyl group, etc. are mentioned, for example.
The alicyclic hydrocarbon group includes a hydroxy group, a carboxyl group, a halogen atom (fluorine atom, bromine atom, etc.), an alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group, t-butoxy group, etc.), It may be substituted with a substituent such as an alkyloxycarbonyl group (such as t-butoxycarbonylmethyloxy group).

Examples of the unsubstituted aryl group for R ⁵⁶ and R ⁵⁷ include aryl groups having 6 to 12 carbon atoms. Specifically, a phenyl group, a naphthyl group, etc. are mentioned, for example.
In addition, this aryl group includes a halogen atom such as fluorine, chlorine, bromine and iodine, a hydroxy group, a thiol group, an alkyl group, and a hetero atom (for example, a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, It may be substituted with a substituent such as an organic group containing a silicon atom).

Moreover, it is preferable that R < ⁵¹ > -R < ⁵⁵ > of general formula (5-1) and (5-2) is a hydrogen atom, a methyl group, or a t-butyl group, respectively.

Examples of the monovalent organic group represented by R ⁵⁸ and R ⁵⁹ in A ⁻ in the general formulas (5-1) and (5-2) include a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and the like. Can be mentioned.
Specific examples of A ⁻ are preferably OH ⁻ , CH ₃ COO ⁻ , and compounds represented by the following formulas (6-1) to (6-5).

Specifically, the above-mentioned photosensitive basic compound is a triphenylsulfonium compound (compound represented by the above general formula (5-1)), and its anion part (A ⁻ ) is OH ⁻ , CH ₃ COO ⁻ , a compound represented by the above formula (6-2), (6-3) or (6-4) is preferable.

  In addition, these acid diffusion control agents (C) may be used individually by 1 type, and may be used in combination of 2 or more type.

  The content of the acid diffusion controller (C) is preferably 15 parts by mass or less, more preferably 0.001 to 10 parts, with respect to 100 parts by mass in total of the resin (B) and the acid-decomposable dissolution inhibiting compound. Part by mass, more preferably 0.005 to 5 parts by mass. When the content of the acid diffusion controller (C) exceeds 15 parts by mass, the sensitivity of the formed resist film and the developability of the exposed part may be deteriorated. When the amount is less than 0.001 part by mass, the pattern shape and dimensional fidelity of the formed resist film may be lowered depending on the process conditions.

[1-5] Other Radiation Sensitive Acid Generator In addition to the acid generator (A) described above, other radiation sensitive acid generators (hereinafter referred to as “other radiation sensitive acid generators”) are included in the radiation sensitive composition of the present invention. Also referred to as “acid generator”) can be further blended.
Examples of other acid generators include onium salt compounds and sulfonic acid compounds other than the acid generator (A).

Examples of the onium salt compounds include iodonium salts, sulfonium salts, phosphonium salts, diazonium salts, and pyridinium salts.
Specifically, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t -Butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) iodonium perfluoro-n-octanesulfonate, cyclohexyl, 2-oxocyclohexyl, methylsulfonium trifluoromethanesulfonate, dicyclohexyl, 2-oxocyclohexyl Sulfonium trifluoromethanesulfonate, 2-oxocyclohexyldimethylsulfonium trifluoromethanesulfonate Sulfonate,

  Bis (4-t-butylphenyl) iodonium nonafluorobutanesulfonate, bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium perfluorooctanesulfonate, bis (4-t- Butylphenyl) iodonium p-toluenesulfonate, bis (4-t-butylphenyl) iodonium 10-camphorsulfonate, 4-trifluoromethylbenzenesulfonate, bis (4-t-butylphenyl) iodonium perfluorobenzenesulfonate, diphenyliodonium p-toluenesulfonate, diphenyliodonium benzenesulfonate, diphenyliodonium 10-camphorsulfonate, diphenyliodonium 4-trifluorome Benzene sulfonate, diphenyliodonium perfluorobenzenesulfonate, bis (p-fluorophenyl) iodonium trifluoromethanesulfonate, bis (p-fluorophenyl) iodonium nonafluoromethanesulfonate, bis (p-fluorophenyl) iodonium 10-camphorsulfonate, p-fluorophenyl) (phenyl) iodonium trifluoromethanesulfonate,

  Triphenylsulfonium nonafluorobutanesulfonate, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium perfluorooctanesulfonate, triphenylsulfonium-2-bicyclo [2.2.1] hept-2-yl-1,1-difluoroethanesulfonate, Triphenylsulfonium-2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, triphenylsulfonium p-toluenesulfonate, triphenylsulfonium benzenesulfonate, triphenylsulfonium 10-camphorsulfonate, triphenylsulfonium 4-trifluoromethylbenzenesulfonate, triphenylsulfonium perfluorobenzenesulfone 4-hydroxyphenyl diphenylsulfonium trifluoromethanesulfonate, tris (p-methoxyphenyl) sulfonium nonafluorobutanesulfonate, tris (p-methoxyphenyl) sulfonium trifluoromethanesulfonate, tris (p-methoxyphenyl) sulfonium perfluorooctane Sulfonate, tris (p-methoxyphenyl) sulfonium p-toluenesulfonate, tris (p-methoxyphenyl) sulfonium benzenesulfonate, tris (p-methoxyphenyl) sulfonium 10-camphor sulfonate, tris (p-fluorophenyl) sulfonium trifluoromethanesulfonate , Tris (p-fluorophenyl) sulfonium p-toluenesulfonate, (p-full Rophenyl) diphenylsulfonium trifluoromethanesulfonate, 4-butoxy-1-naphthyltetrahydrothiophenium nonafluorobutanesulfonate, and 4-butoxy-1-naphthyltetrahydrothiophenium-2-bicyclo [2.2.1] hepta-2 -Yl-1,1,2,2-tetrafluoroethanesulfonate and the like.

Examples of the sulfonic acid compounds include alkyl sulfonic acid esters, alkyl sulfonic acid imides, haloalkyl sulfonic acid esters, aryl sulfonic acid esters, and imino sulfonates.
Specifically, benzoin tosylate, pyrogallol tris (trifluoromethanesulfonate), nitrobenzyl-9,10-diethoxyanthracene-2-sulfonate, trifluoromethanesulfonylbicyclo [2.2.1] hept-5-ene- 2,3-dicarbodiimide, nonafluoro-n-butanesulfonylbicyclo [2.2.1] hept-5-ene-2,3-dicarbodiimide, perfluoro-n-octanesulfonylbicyclo [2.2.1] hept -5-ene-2,3-dicarbodiimide, N-hydroxysuccinimide trifluoromethanesulfonate, N-hydroxysuccinimide nonafluoro-n-butanesulfonate, N-hydroxysuccinimide perfluoro-n-octanesulfonate, 1,8-naphthalenedical Phosphate imide trifluoromethanesulfonate, 1,8-naphthalenedicarboxylic acid imide nonafluoro -n- butane sulfonate, and 1,8-naphthalenedicarboxylic acid imide perfluoro -n- octanesulfonate, and the like.

  Among these other acid generators, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate Bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) iodonium perfluoro-n-octanesulfonate, cyclohexyl, 2-oxocyclohexyl, methylsulfonium trifluoromethanesulfonate, Dicyclohexyl 2-oxocyclohexylsulfonium trifluoromethanesulfonate, 2-oxocyclohexyldimethylsulfonium Trifluoromethanesulfonate,

Trifluoromethanesulfonylbicyclo [2.2.1] hept-5-ene-2,3-dicarbodiimide, nonafluoro-n-butanesulfonylbicyclo [2.2.1] hept-5-ene-2,3-dicarbodiimide , Perfluoro-n-octanesulfonylbicyclo [2.2.1] hept-5-ene-2,3-dicarbodiimide, N-hydroxysuccinimide trifluoromethanesulfonate, N-hydroxysuccinimide nonafluoro-n- Butanesulfonate, N-hydroxysuccinimide perfluoro-n-octanesulfonate, 1,8-naphthalenedicarboxylic acid imide trifluoromethanesulfonate, triphenylsulfonium nonafluorobutanesulfonate, triphenylsulfonium trifluoromethanesulfonate, Phenylsulfonium-2-bicyclo [2.2.1] hept-2-yl-1,1-difluoroethanesulfonate, triphenylsulfonium-2-bicyclo [2.2.1] hept-2-yl-1,1, 2,2-tetrafluoroethanesulfonate, 4-butoxy-1-naphthyltetrahydrothiophenium nonafluorobutanesulfonate, and 4-butoxy-1-naphthyltetrahydrothiophenium-2-bicyclo [2.2.1] hepta- 2-yl-1,1,2,2-tetrafluoroethanesulfonate is preferred.
In addition, these other acid generators may be used individually by 1 type, and may be used in combination of 2 or more type.

  The compounding amount of the other acid generator is 0 to 80 parts by mass with respect to 100 parts by mass of the acid generator (A) from the viewpoint of ensuring the sensitivity and developability of the resist film formed from the radiation-sensitive composition. It is preferable that it is 0-50 mass parts. When the blending amount of the other acid generator exceeds 80 parts by mass, the resolution performance may be deteriorated.

[1-6] Other components In addition to the acid generator (A), resin (B), acid diffusion controller (C), and other acid generators described above, the radiation-sensitive composition of the present invention includes: As other components, various additives such as a solvent, a surfactant, a sensitizer, and an aliphatic additive can be further blended.

  Examples of the solvent include ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, and ethylene glycol mono-n-butyl ether acetate; propylene glycol Propylene glycol monoalkyl ethers such as monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether and propylene glycol mono-n-butyl ether; propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol di-n- Propyl ether and propylene glycol di-n-butyl Propylene glycol dialkyl ethers such as ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl -n- propyl ether acetate and propylene glycol mono -n- butyl ether acetate;

  Lactic acid esters such as methyl lactate, ethyl lactate, n-propyl lactate and i-propyl lactate; formic acid esters such as n-amyl formate and i-amyl formate; ethyl acetate, n-propyl acetate, i-acetate Acetates such as propyl, n-butyl acetate, i-butyl acetate, n-amyl acetate, i-amyl acetate, 3-methoxybutyl acetate and 3-methyl-3-methoxybutyl acetate; i-propyl propionate, propionate Propionates such as n-butyl acid, i-butyl propionate and 3-methyl-3-methoxybutyl propionate; ethyl hydroxyacetate, ethyl 2-hydroxy-2-methylpropionate, 2-hydroxy-3- Methyl methylbutyrate, ethyl methoxyacetate, ethyl ethoxyacetate, methyl 3-methoxypropionate, 3- Other esters such as ethyl toxipropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, 3-methyl-3-methoxybutyl butyrate, methyl acetoacetate, ethyl acetoacetate, methyl pyruvate and ethyl pyruvate Aromatic hydrocarbons such as toluene and xylene; ketones such as methyl ethyl ketone, 2-pentanone, 2-hexanone, 2-heptanone, 3-heptanone, 4-heptanone and cyclohexanone; N-methylformamide, N, N- Examples thereof include amides such as dimethylformamide, N-methylacetamide, N, N-dimethylacetamide and N-methylpyrrolidone; lactones such as γ-butyrolacun. These solvents may be used individually by 1 type, and may be used in combination of 2 or more type.

In the present invention, from the viewpoint of applicability, it is preferable that at least one selected from ethylene glycol monoalkyl ether acetates and propylene glycol monoalkyl ether acetates is contained as a solvent.
The total content of ethylene glycol monoalkyl ether acetates and propylene glycol monoalkyl ether acetates is preferably 70 to 100 parts by mass, more preferably 70 to 100 parts when the total solvent is 100 parts by mass. 80 parts by mass.

  The amount of the solvent is preferably such that the total solid concentration of the radiation-sensitive composition is 1 to 70% by mass, more preferably 1 to 15% by mass, and still more preferably 1 to 10%. It is the amount that becomes mass%. When the blending amount is in the above range, the viscosity of the composition does not become too high and coating becomes difficult, and a resist film having a sufficient thickness can be formed.

  The radiation-sensitive composition of the present invention comprises the above-described acid generator (A), resin (B), and, if necessary, an acid diffusion controller (C), other acid generators, surfactants, Additives such as sensitizers can be prepared by uniformly dissolving in a solvent such that the total solid content concentration is in the above range. In addition, after preparing in this way, it is preferable to filter with a filter with a pore diameter of about 0.2 μm, for example.

The surfactant is a component having an action of improving coatability, striation, developability and the like.
It is preferable that the compounding quantity of surfactant is 2 mass parts or less with respect to a total of 100 mass parts of resin (B) and an acid-decomposable dissolution inhibiting compound, More preferably, it is 0.001-2 mass parts. .

  The sensitizer absorbs radiation energy and has the effect of transmitting the absorbed energy to the acid generator (A) to increase the amount of acid produced. The apparent sensitivity of the radiation-sensitive composition. It has the effect of improving.

  It is preferable that the compounding quantity of a sensitizer is 20 mass parts or less with respect to a total of 100 mass parts of resin (B) and an acid-decomposable dissolution inhibiting compound, More preferably, it is 0.1-20 mass parts. .

  Further, by blending a dye or a pigment, the latent image in the exposed area can be visualized, and the influence of halation during exposure can be reduced. Moreover, the adhesiveness of a resist film and a board | substrate can be improved by containing an adhesion aid.

The said alicyclic additive is a component which has the effect | action which further improves dry etching tolerance, a pattern shape, adhesiveness with a board | substrate, etc.
Examples of such alicyclic additives include adamantane derivatives, deoxycholic acid esters, lithocholic acid esters, 3- [2-hydroxy-2,2-bis (trifluoromethyl) ethyl] tetracyclo [6 2.1.1 ^3,6 . 0 ^2,7 ] dodecane and the like. In addition, these alicyclic additives may be used individually by 1 type, and may be used in combination of 2 or more type.

  In addition to these additives, an alkali-soluble polymer, a low-molecular alkali-solubility control agent having an acid-dissociable protecting group, an antihalation agent, a storage stabilizer, an antifoaming agent, etc. may be blended. it can.

[2] Method for Forming Resist Pattern The radiation-sensitive composition of the present invention is useful as a material capable of forming a chemically amplified positive resist film. Specifically, for example, in a chemically amplified positive resist film made of a radiation-sensitive composition containing the resin (B), the resin (by the action of acid generated from the acid generator (A) by exposure) The acid dissociable group in B) is eliminated, and the resin (B) becomes alkali-soluble. That is, an alkali-soluble site is generated in the resist film. This alkali-soluble portion is an exposed portion of the resist, and this exposed portion can be dissolved and removed by an alkali developer. In this way, a positive resist pattern having a desired shape can be formed. This will be specifically described below.

In order to form a resist pattern using the radiation-sensitive composition of the present invention, first, a resist film is formed using the radiation-sensitive composition of the present invention.
As the radiation-sensitive composition, for example, as described above, after adjusting the total solid content concentration, a composition filtered with a filter having a pore diameter of about 0.2 μm can be used. A resist film is formed by applying this radiation-sensitive composition onto a substrate such as a silicon wafer or a wafer coated with aluminum by an appropriate application means such as spin coating, cast coating, or roll coating. To do. Thereafter, in some cases, heat treatment (hereinafter referred to as “PB”) may be performed at a temperature of about 70 to 160 ° C. in advance.

  Next, the resist film is exposed so that a predetermined resist pattern is formed. Examples of radiation that can be used for this exposure include (extreme) far ultraviolet rays such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), EUV (extreme ultraviolet light, wavelength 13.5 nm, etc.), and synchro Examples include X-rays such as tron radiation, and charged particle beams such as electron beams. Moreover, exposure conditions, such as exposure amount, can be suitably selected according to the compounding composition of a radiation sensitive composition, the kind of additive, etc. This exposure can also be immersion exposure.

  After the exposure, heat treatment (hereinafter referred to as “PEB”) is preferably performed. By this PEB, it is possible to smoothly proceed with elimination of the acid dissociable group of the resin (B). Although the heating conditions for PEB can be appropriately selected depending on the composition of the radiation-sensitive composition, it is preferably 30 to 200 ° C, more preferably 50 to 170 ° C.

  In the present invention, in order to maximize the potential of the radiation-sensitive composition, it is used, for example, as disclosed in Japanese Patent Publication No. 6-12452 (Japanese Patent Laid-Open No. 59-93448). An organic or inorganic antireflection film can also be formed on the substrate. Further, in order to prevent the influence of basic impurities contained in the environmental atmosphere, a protective film can be provided on the resist film as disclosed in, for example, JP-A-5-188598. These techniques can be used in combination.

  Next, a predetermined resist pattern is formed by developing the exposed resist film. Examples of the developer used for development include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, Triethylamine, methyldiethylamine, ethyldimethylamine, triethanolamine, tetramethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene, 1,5-diazabicyclo- [ 4.3.0] An alkaline aqueous solution in which at least one alkaline compound such as 5-nonene is dissolved is preferable.

  The concentration of the alkaline aqueous solution is preferably 10% by mass or less. When the concentration of the alkaline aqueous solution exceeds 10% by mass, the unexposed area may be dissolved in the developer. Moreover, it is preferable that a developing solution is pH 8-14, More preferably, it is pH 9-14.

  Moreover, an organic solvent can also be added to the developing solution which consists of alkaline aqueous solution, for example. Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone, methyl i-butyl ketone, cyclopentanone, cyclohexanone, 3-methylcyclopentanone, and 2,6-dimethylcyclohexanone; methanol, ethanol, n-propyl alcohol, i Alcohols such as propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclopentanol, cyclohexanol, 1,4-hexanediol, 1,4-hexanedimethylol; ethers such as tetrahydrofuran and dioxane; ethyl acetate And esters such as n-butyl acetate and i-amyl acetate; aromatic hydrocarbons such as toluene and xylene; phenol, acetonylacetone and dimethylformamide. These organic solvents may be used individually by 1 type, and may be used in combination of 2 or more type.

  The blending amount of the organic solvent is preferably 100 parts by volume or less with respect to 100 parts by volume of the alkaline aqueous solution. When the blending amount of the organic solvent exceeds 100 parts by volume, the developability is lowered, and there is a possibility that the remaining development in the exposed part increases. In addition, an appropriate amount of a surfactant or the like can be added to the developer composed of an alkaline aqueous solution. In addition, after developing with the developing solution which consists of alkaline aqueous solution, it can also wash with water and can be dried.

〔一般式（１）において、Ｒ ^１ は相互に独立に、水素原子、フッ素原子、フルオロアルキルを示し、且つＲ ^１ のうち少なくとも１つは、フッ素原子、又はフルオロアルキルを示す。Ｒ ^２ は相互に独立に、アルコキシカルボニル（アルコキシ基は、フッ素原子で置換されていてもよい）、シクロアルコキシカルボニル（シクロアルキル基は、縮合多環式ラクトンを包含する）を示す。ｎは１を示す。Ｍ ^＋ は１価の有機スルホニウムカチオンを示す。〕
尚、この「新規化合物」については、上述の感放射線性組成物の酸発生剤（Ａ）における説明をそのまま適用することができる。
本発明の新規化合物は、溶剤への溶解性が高く、上述の感放射線性組成物における酸発生剤（Ａ）として好適に用いることができる。 [3] The novel compounds novel compounds of the present invention is characterized by represented by the following following general formula (1).

[In General Formula (1), R ¹ independently represents a hydrogen atom, a fluorine atom, or a fluoroalkyl , and at least one of R ¹ represents a fluorine atom or a fluoroalkyl. R ² independently represents alkoxycarbonyl (the alkoxy group may be substituted with a fluorine atom) or cycloalkoxycarbonyl (the cycloalkyl group includes a condensed polycyclic lactone). n represents 1. M ⁺ represents a monovalent organic sulfonium cation. ]
Note that the "new compounds" can be applied as it is Rusetsu bright put the acid generator of the radiation-sensitive composition as described above (A).
The novel compound of the present invention has high solubility in a solvent, and can be suitably used as the acid generator (A) in the above-mentioned radiation-sensitive composition.

  Hereinafter, the embodiment of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. Here, “part” and “%” are based on mass unless otherwise specified. Further, in this example, EB (electron beam) is used for the exposure of the resist film, but the basic resist characteristics are similar even when short wavelength radiation such as EUV is used. It is also known that there is a correlation between them.

[1] Synthesis of Resin (Synthesis Example 1) Synthesis of Resin (B-1) 55 g of p-acetoxystyrene and a compound represented by the following formula (M-1) (hereinafter also referred to as “compound (M-1)”) ) 45 g, 4 g of azobisisobutyronitrile, and 1 g of t-dodecyl mercaptan were dissolved in 100 g of propylene glycol monomethyl ether, and the polymerization was carried out for 16 hours while maintaining the reaction temperature at 70 ° C. in a nitrogen atmosphere. After the polymerization, the reaction solution was dropped into 1000 g of n-hexane to coagulate and purify the copolymer. Next, 150 g of propylene glycol monomethyl ether was added to the copolymer, and then 150 g of methanol, 34 g of triethylamine, and 6 g of water were further added, and a hydrolysis reaction was performed for 8 hours while refluxing at the boiling point. After the reaction, the solvent and triethylamine were distilled off under reduced pressure, and the obtained copolymer was dissolved in 150 g of acetone, then dropped into 2000 g of water to solidify, and the resulting white powder was filtered and filtered at 50 ° C. under reduced pressure. Dried overnight.
The obtained copolymer has Mw of 10,000 and Mw / Mn of 2.1, and as a result of ¹³ C-NMR analysis, the repeating unit derived from p-hydroxystyrene and the repeating derived from compound (M-1) The copolymer had a unit content ratio (molar ratio) of 65:35. Hereinafter, this copolymer is referred to as “resin (B-1)”.

(Synthesis Example 2) Synthesis of Resin (B-2) 53 g of p-acetoxystyrene, 47 g of a compound represented by the following formula (M-2) (hereinafter also referred to as “compound (M-2)”), azobisiso After 4 g of butyronitrile and 0.2 g of t-dodecyl mercaptan were dissolved in 200 g of propylene glycol monomethyl ether, polymerization was performed for 6 hours while maintaining the reaction temperature at 70 ° C. in a nitrogen atmosphere. After the polymerization, the reaction solution was dropped into 2000 g of n-hexane to coagulate and purify the copolymer. Next, 150 g of propylene glycol monomethyl ether was again added to the copolymer, and then 150 g of methanol, 37 g of triethylamine and 7 g of water were further added, and a hydrolysis reaction was performed for 8 hours while refluxing at the boiling point. After the reaction, the solvent and triethylamine were distilled off under reduced pressure, and the obtained copolymer was dissolved in 150 g of acetone, then dropped into 2000 g of water to solidify, and the resulting white powder was filtered and filtered at 50 ° C. under reduced pressure. Dried overnight.
The obtained copolymer has Mw of 13000 and Mw / Mn of 2.4. As a result of ¹³ C-NMR analysis, the repeating unit derived from p-hydroxystyrene and the repetition derived from the compound (M-2) The copolymer had a unit content ratio (molar ratio) of 50:50. Hereinafter, this copolymer is referred to as “resin (B-2)”.

(Synthesis Example 3) Synthesis of Resin (B-3) 55 g of a compound represented by the following formula (M-3) (hereinafter also referred to as “compound (M-3)”), represented by the following formula (M-4) The compound (hereinafter also referred to as “compound (M-4)”) 45 g and azobisisobutyronitrile 3 g were dissolved in 300 g of methyl ethyl ketone, and the reaction temperature was maintained at 78 ° C. in a nitrogen atmosphere. Polymerized for 6 hours. After the polymerization, the reaction solution was dropped into 2000 g of methanol to coagulate and purify the copolymer. The copolymer was then washed twice with 300 g of methanol, and the resulting white powder was filtered and dried overnight at 50 ° C. under reduced pressure.
The obtained copolymer has Mw of 7000 and Mw / Mn of 2.1. As a result of ¹³ C-NMR analysis, the copolymer is derived from the repeating unit derived from the compound (M-3) and the compound (M-4). This was a copolymer having a repeating unit content ratio (molar ratio) of 47:53. Hereinafter, this copolymer is referred to as “resin (B-3)”.

In addition, the measurement of the weight average molecular weight (Mw) and the number average molecular weight (Mn) in the present Example uses Tosoh GPC columns (2 G2000HXL, 1 G3000HXL, 1 G4000HXL), flow rate: 1.0 ml / min, Elution solvent: Tetrahydrofuran, Column temperature: It was measured by gel permeation chromatography (GPC) using monodisperse polystyrene as a standard under analysis conditions of 40 ° C. Further, the degree of dispersion Mw / Mn was calculated from the measurement results.
The ¹³ C-NMR analysis was measured using a model “JNM-EX270” manufactured by JEOL.

[2] Preparation of radiation-sensitive composition (Example 1)
As shown in Table 1, 100 parts of resin (B-1) prepared in Synthesis Example 1, 20 parts of acid generator (A-1), 2 parts of acid diffusion controller (C-1), solvent (D-1) ) 1400 parts and 3300 parts of solvent (D-2) were mixed, and the resulting mixture was filtered through a membrane filter having a pore size of 200 nm to prepare a composition solution (the radiation-sensitive composition of Example 1). did.

(Examples 2 to 9 and Comparative Example 1)
Resin (B), acid generator (A), acid diffusion controller (C), and solvent (D) were mixed in the amounts shown in Table 1, and the resulting mixture was filtered through a membrane filter having a pore size of 200 nm. By doing this, each composition solution (radiation sensitive composition) of Examples 2-9 and Comparative Example 1 was prepared.

  Details of the acid generator (A), resin (B), acid diffusion controller (C) and solvent (D) in Table 1 are shown below.

<Acid generator (A)>
(A-1) to (A-7): Compounds represented by the following formulas (A-1) to (A-7)

<Resin (B)>
(B-1): Resin (B-1) obtained in Synthesis Example 1
(B-2): Resin (B-2) obtained in Synthesis Example 2 above
(B-3): Resin (B-3) obtained in Synthesis Example 3
<Acid diffusion controller (C)>
(C-1): Tri-n-octylamine (C-2): Compound represented by the following formula (C-2)

<Solvent (D)>
(D-1): Ethyl lactate (D-2): Propylene glycol monomethyl ether acetate

[3] Evaluation of Radiation Sensitive Composition In “Clean Track ACT-8” manufactured by Tokyo Electron Co., Ltd., a composition solution (radiation sensitive compositions of Examples 1 to 9 and Comparative Example 1) on a silicon wafer. After spin coating, PB (heat treatment) was performed under the conditions shown in Table 2 to form a resist film having a thickness of 50 nm. Thereafter, the resist film was irradiated with an electron beam using a simple electron beam drawing apparatus (manufactured by Hitachi, Ltd., model “HL800D”, output: 50 KeV, current density: 5.0 amperes / cm ² ). After the electron beam irradiation, PEB was performed under the conditions shown in Table 2. Thereafter, a 2.38 mass% tetramethylammonium hydroxide aqueous solution was used and developed by the paddle method at 23 ° C. for 1 minute, followed by washing with pure water and drying to form a resist pattern.
Each evaluation test was performed on the resist pattern thus formed, and the evaluation results are shown in Table 2.

(1) Sensitivity (L / S)
A pattern (a so-called line-and-space pattern (1L1S)) composed of a line portion having a line width of 130 nm and a space portion (that is, a groove) having a spacing of 130 nm formed by adjacent line portions is 1: 1. The exposure amount formed in the line width was set as the optimum exposure amount, and the sensitivity (μC / cm ² ) was evaluated based on the optimum exposure amount.

(2) Nano-edge roughness A line-and-space pattern (1L1S) with a design line width of 130 nm is scanned with a scanning electron microscope for semiconductors (high resolution FEB measuring device, trade name “S-9220”, manufactured by Hitachi, Ltd. ). With respect to the observed shape, as shown in FIG. 1 and FIG. 2, the line width and the design line at the most conspicuous portion of the unevenness generated along the lateral surface 2 a of the line portion 2 of the resist film formed on the silicon wafer 1. Nano edge roughness was evaluated by measuring the difference “ΔCD” from the width of 130 nm with CD-SEM (manufactured by Hitachi High-Technologies Corporation, “S-9220”). In addition, the unevenness | corrugation shown in FIG.1 and FIG.2 is exaggerated from actuality.

(3) Resolution (L / S)
For the line-and-space pattern (1L1S), the minimum line width (nm) of the line pattern resolved with the optimum exposure dose was taken as the resolution.

  As is clear from Table 2, the radiation sensitive compositions of Examples 1 to 9 containing any of the acid generators (A-1) to (A-3) and (A-5) to (A-7). The product is not the acid generators (A-1) to (A-3) and (A-5) to (A-7), but the acid sensitivity of Comparative Example 1 containing the acid generator (A-4). Compared to the composition, it is more sensitive to electron beam or extreme ultraviolet rays, has low roughness and excellent resolution, and can be used to form fine patterns with high precision and stability. A positive resist film could be formed.

  The radiation-sensitive composition of the present invention is not only excellent in the resolution of the line and space pattern at the time of resist pattern formation, but also excellent in nano edge roughness, so it is useful for fine pattern formation by EB, EUV and X-rays. is there. Therefore, the radiation-sensitive composition of the present invention is extremely useful as a material capable of forming a chemically amplified resist for manufacturing semiconductor devices, which is expected to be further miniaturized in the future.

  DESCRIPTION OF SYMBOLS 1; Base material, 2; Resist pattern, 2a;

Claims (7)

A radiation-sensitive composition comprising a radiation-sensitive acid generator represented by the following general formula (1) and a solvent.

[In General Formula (1), R ¹ is independently a hydrogen atom, a fluorine atom, or a linear or branched group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms are substituted with fluorine atoms. And at least one of R ¹ is a fluorine atom or a linear or branched group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms are substituted with fluorine atoms. These are monovalent hydrocarbon groups . R ² independently represents ^a —COOR ^a group. R ^a is independently of each other: (a1) a substituted or unsubstituted linear or branched monovalent hydrocarbon group having 1 to 30 carbon atoms, (a2) an ester bond, an amide bond, a urethane bond and a sulfide bond. The hydrocarbon group (a1), (a3) a substituted or unsubstituted monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms, or (a4) an ester bond The aliphatic hydrocarbon group (a3) further having a linking group selected from an amide bond, a urethane bond and a sulfide bond, (a5) a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or (a6) a substituted group Alternatively, it represents a cyclic organic group which may have an unsubstituted monovalent heteroatom having 4 to 30 carbon atoms . n represents an integer of 0 to 3. M ⁺ represents a monovalent onium cation. ] The radiation-sensitive composition according to claim 1, wherein the radiation-sensitive acid generator is a radiation-sensitive acid generator represented by the following general formula (2).

[In General Formula (2), R ³ is independently a hydrogen atom, a fluorine atom, or a linear or branched group having 1 to 30 carbon atoms in which some or all of the hydrogen atoms are substituted with fluorine atoms. And at least one of R ³ is a fluorine atom or a linear or branched group having 1 to 30 carbon atoms in which part or all of the hydrogen atoms are substituted with fluorine atoms These are monovalent hydrocarbon groups. R ⁴ is independently of each other (a1) a substituted or unsubstituted C 1-30 linear or branched monovalent hydrocarbon group, (a2) an ester bond, an amide bond, a urethane bond and a sulfide bond. The hydrocarbon group (a1), (a3) a substituted or unsubstituted monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms, or (a4) an ester bond The aliphatic hydrocarbon group (a3) further having a linking group selected from an amide bond, a urethane bond and a sulfide bond, (a5) a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or (a6) a substituted group Alternatively, it represents a cyclic organic group which may have an unsubstituted monovalent heteroatom having 4 to 30 carbon atoms. M ⁺ represents a monovalent onium cation. ] The radiation-sensitive composition according to claim 2, wherein at least one of R ³ in the general formula (2) is a fluorine atom or a trifluoromethyl group. R ⁴ in the general formula (2) is independently of each other (a3) a substituted or unsubstituted monovalent aliphatic hydrocarbon group having a cyclic or cyclic structure having 3 to 30 carbon atoms, (a4) an ester bond The hydrocarbon group (a3) further having a linking group selected from an amide bond, a urethane bond and a sulfide bond, or (a5) a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. The radiation-sensitive composition as described in 1. The radiation-sensitive composition according to any one of claims 1 to 4, wherein the monovalent onium cation (M ⁺ ) in the general formula (1) or (2) is a sulfonium cation represented by the following general formula (m1-1). Sex composition.

[In General Formula (m1-1), R ^{111 to} R ¹¹³ are each independently a hydroxy group, a halogen atom, an alkyl group which may have a substituent, a cycloalkyl group, an alkoxy group, or —SR. ¹¹⁴ group (R ¹¹⁴ represents an alkyl group which may have a substituent or an aryl group), or —SO ₂ —R ¹¹⁵ group (R ¹¹⁵ is an alkyl which may have a substituent). A group, a cycloalkyl group, an alkoxy group, or an aryl group. However, at least one of R ¹¹¹ is a —SO ₂ —R ¹¹⁵ group. l is an integer of 1-5. m is an integer of 0-5. n is an integer of 0-5. ] Furthermore, the radiation sensitive composition in any one of the Claims 1 thru | or 5 containing the resin containing at least 1 sort (s) of the repeating unit represented by the following general formula (b-1)-(b-5). .

[In General Formula (b-1), R ¹¹ represents a hydrogen atom or a methyl group. R ¹² represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. k represents an integer of 0 to 3, l represents an integer of 0 to 3, and k + l ≦ 5 is satisfied. ]

[In General Formula (b-2), R ¹³ represents a hydrogen atom or a methyl group. R ¹⁴ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. m represents an integer of 0 to 3, n represents an integer of 0 to 3, and satisfies m + n ≦ 5. ]

[In General Formula (b-3), R ¹⁵ represents a hydrogen atom or a methyl group. R ¹⁶ represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. p represents an integer of 0 to 3, q represents an integer of 0 to 3, and satisfies p + q ≦ 5. ]

[In General Formula (b-4), R ¹⁷ represents a hydrogen atom or a methyl group. R ¹⁸ represents a linear or branched alkyl group having 1 to 12 carbon atoms or a linear or branched alkoxy group having 1 to 12 carbon atoms. r represents an integer of 0 to 3, and s represents an integer of 0 to 3. ]

[In General Formula (b-5), R ¹⁹ represents a hydrogen atom or a methyl group. ] A compound represented by the following general formula (1):

In [general formula (1), R ¹ independently of one another, a hydrogen atom, a fluorine atom, a fluoroalkyl, and at least one of R ¹ represents a fluorine atom, or a fluoroalkyl. R ² independently represents alkoxycarbonyl (the alkoxy group may be substituted with a fluorine atom) or cycloalkoxycarbonyl (the cycloalkyl group includes a condensed polycyclic lactone) . n represents 1 . M ⁺ represents a monovalent organic sulfonium cation. ]

Images