JP2006322988A - Radiation-sensitive resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a preferable radiation-sensitive resin composition for minute pattern formation due to an electron ray and an extreme ultraviolet ray. <P>SOLUTION: The radiation-sensitive resin composition has the characteristics that a resolution in forming a pattern is 90 nm or less in a line and space pattern and 100 nm or less in an isolated line pattern, and includes an acid forming agent having a structure of the following formula (1), and an acid dissociation group contained resin being an alkali insoluble or hardly soluble resin having an acid dissociation group and being alkali soluble by dissociating the acid dissociation group. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a radiation sensitive resin composition suitable for fine processing. In particular, the present invention relates to a radiation-sensitive resin composition suitable for forming a fine pattern using an electron beam (hereinafter abbreviated as EB) or extreme ultraviolet rays (hereinafter abbreviated as EUV).

  In the field of microfabrication represented by the manufacture of integrated circuit elements, in order to obtain a higher degree of integration of integrated circuits, miniaturization of design rules in lithography is progressing rapidly, and microfabrication is performed stably. The development of lithography processes that can do this is strongly promoted. However, since it is difficult to form a fine pattern of 100 nm or less with high accuracy by the conventional method using KrF or ArF excimer laser, a method using EB or EUV has been proposed.

Various types of radiation-sensitive resin compositions used as such positive resist materials for electron beams or extreme ultraviolet rays used in such ultrafine processing have been proposed.
(1) A methacrylic main chain-cutting radiation sensitive resin composition such as PMMA (polymethyl methacrylate):
Although the resolution is excellent, there are problems in etching resistance and sensitivity, and it is difficult to put it to practical use. Poly t-butyl α-chloromethylstyrene (see Patent Document 1) having a good balance between resolution and sensitivity, and patent application (see Patent Document 2) in which atoms (N, O, S) that are easily cut by an electron beam are introduced at the resin terminal ) Has been. However, although improvement in sensitivity is recognized, sensitivity and etching resistance have not reached a practical level.
(2) Chemically amplified radiation-sensitive resin composition having a polyhydroxystyrene-based resin (resin for KrF excimer) and a novolak (resin for i-line) partially protected with an acid-dissociable functional group and an acid generator:
Excellent balance of sensitivity, resolution, and etching resistance, partially acetal protected polyhydroxystyrene resin + acid generator (see Patent Document 3), various acid dissociable partially protected polyhydroxystyrene resins + fluorine-containing aromatic sulfonic acid generated onium salt + Fluorine-based or silicon-based surfactant (see Patent Document 4), onium salt having at least one electron-withdrawing group (F, cyano group, nitro group) as a cation moiety substituent (see Patent Document 5), disulfonyl group Various patents have been filed, such as a resin having an N-oxyimide sulfonyl group (see Patent Document 7), and the like. However, the film surface roughness (hereinafter referred to as roughness), sensitivity, and resolution at the time of forming a fine pattern has not reached a practical level.
(3) As an acid generator, triphenylsulfonium 1,1,2,2-tetrafluoro-2- (norbornan-2-yl) ethanesulfonate (see Patent Document 8), triphenylsulfonium 1,1-difluoro 2- (Bicyclo [2.2.1] heptan-2-yl) ethanesulfonate (see Patent Document 9) is already known. However, the positive-type radiation-sensitive resin composition using EB or EUV has a problem that it cannot be sufficient for the recent finer sensitivity and resolution.

JP 2000-147777 A JP 11-29612 A JP-A-6-194842 JP 2000-187330 A JP 2001-075283 A JP 2002-072483 A JP 2002-107920 A JP 2004-117959 A International Publication No. WO2004 / 078703

The present invention has been made to address the above problems, and is a positive radiation-sensitive resin composition that is excellent in roughness, etching resistance, sensitivity, resolution, and can form a fine pattern with high accuracy and stability. The purpose is to provide goods.
A further object of the present invention is to provide a chemically amplified positive radiation sensitive resin composition suitable for EB and EUV that is effectively sensitive to electron beams or extreme ultraviolet rays.

（式（１）において、Ｒ¹は−Ｒ⁵、−ＣＯＲ⁶、−ＣＯＯＲ⁶、−ＣＯＮ（Ｒ⁶)（Ｒ⁷)、−Ｎ（Ｒ⁶)（Ｒ⁷)、−Ｎ（Ｒ⁶)ＣＯ（Ｒ⁷)、−Ｎ（Ｒ⁶)ＣＯＯＲ⁷、−Ｎ（ＣＯＲ⁶)（ＣＯＲ⁷)、−ＳＲ⁶、−ＳＯＲ⁶、−ＳＯ₂Ｒ⁶または−ＳＯ₂（ＯＲ⁶)を表し、該Ｒ¹が複数存在する場合それらは相互に同一でも異なってもよく、また該Ｒ¹がノルボルナン構造中に含まれる場合それらは炭素原子と共に環を形成してもよく、また該Ｒ¹が複数存在する場合何れか２つ以上のＲ¹が相互に結合して環を形成してもよく、上記Ｒ⁵は置換もしくは非置換の炭素数１〜３０の直鎖状、分岐状もしくは環状の１価の炭化水素基、置換もしくは非置換の炭素数６〜３０のアリール基または置換もしくは非置換の原子数４〜３０の１価のヘテロ環状有機基を表し、上記Ｒ⁶およびＲ⁷は相互に独立に水素原子、置換もしくは非置換の炭素数１〜３０の直鎖状、分岐状もしくは環状の１価の炭化水素基、置換もしくは非置換の炭素数６〜３０のアリール基または置換もしくは非置換の原子数４〜３０の１価のヘテロ環状有機基を表し、
Ｒ²、Ｒ³およびＲ⁴は相互に独立に水素原子または炭素数１〜３０の直鎖状、分岐状もしくは環状のアルキル基を表し、
ｋは０以上の整数、ｎは０〜５の整数であり、Ｍ^＋は１価のオニウムカチオンを表す。）
また、本発明の感放射線性樹脂組成物は、電子線または１４０ｎｍ以下の波長を有する放射線照射によりアルカリ可溶性になることを特徴とする。 The radiation sensitive resin composition of the present invention is a radiation sensitive resin composition having a resolution of 90 nm or less in a line and space pattern and 100 nm or less in an isolated line pattern at the time of pattern formation,
The resin composition is an acid generator having a structure of the following formula (1) and an alkali-insoluble or hardly-alkali-soluble resin having an acid-dissociable group, and becomes alkali-soluble when the acid-dissociable group is dissociated. And an acid dissociable group-containing resin.

(In the formula (1), R ^{1 -R 5, -COR 6, -COOR 6} , -CON (R 6) (R 7), - N (R 6) (R 7), - N (R 6) ^{CO (R 7), - N} (R 6) COOR 7, -N (COR 6) (COR 7), - SR 6, -SOR 6, represents -SO ₂ R ^6, or -SO ₂ (oR ^6), When a plurality of R ¹ are present, they may be the same or different from each other, and when R ¹ is contained in a norbornane structure, they may form a ring together with a carbon atom, and a plurality of R ¹ may be present. When present, any two or more R ^{1 s} may be bonded to each other to form a ring, and the R ⁵ is a substituted or unsubstituted 1 to 30 linear, branched or cyclic 1 carbon atom. A valent hydrocarbon group, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted monovalent heterocyclic group having 4 to 30 atoms. Represents a group, the R ⁶ and R ⁷ individually represent a hydrogen atom, a substituted or unsubstituted C 1-30 linear, branched or cyclic, monovalent hydrocarbon group, a substituted or unsubstituted An aryl group having 6 to 30 carbon atoms or a substituted or unsubstituted monovalent heterocyclic organic group having 4 to 30 atoms;
R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms,
k is an integer of 0 or more, n is an integer of 0 to 5, and M ⁺ represents a monovalent onium cation. )
The radiation-sensitive resin composition of the present invention is characterized in that it becomes alkali-soluble by irradiation with an electron beam or radiation having a wavelength of 140 nm or less.

Since the acid generator having the structure of the formula (1) has a strong fluorine-containing electron withdrawing group at the α-position carbon atom of the —SO ₃ ^— group, the acidity of the generated sulfonic acid is high, and the boiling point is high. Since it is sufficiently high, it is difficult to volatilize during the photolithography process, and the acid diffusion length in the resist film is appropriately short. Further, since the fluorine content in the generated sulfonic acid is smaller than that of higher perfluoroalkanesulfonic acid, the combustibility is relatively high and the human body accumulation property is also low. For this reason, by using an acid generator having the structure of formula (1), the resolution at the time of pattern formation is 90 nm or less for a line-and-space pattern and 100 nm or less for an isolated line pattern, or an electron beam or 140 nm or less. It becomes alkali-soluble when irradiated with radiation having a wavelength.

Hereinafter, embodiments of the present invention will be described in detail.
In the acid generating agent formula (1), R ^{1 -R 5, -COR 6, -COOR 6} , -CON (R 6) (R 7), - N (R 6) (R 7), - N (R ^{6) CO (R 7),} - N (R 6) COOR 7, -N (COR 6) (COR 7), - SR 6, -SOR 6, -SO 2 R 6 or -SO ₂ a (oR ⁶⁾ To express.
Here, R ⁵ is a substituted or unsubstituted linear, branched or cyclic monovalent hydrocarbon group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, An unsubstituted monovalent heterocyclic organic group having 4 to 30 atoms is represented.
R ⁶ and R ⁷ are each independently a hydrogen atom, a substituted or unsubstituted C 1-30 linear, branched or cyclic monovalent hydrocarbon group, a substituted or unsubstituted carbon number. Represents a 6-30 aryl group or a substituted or unsubstituted monovalent heterocyclic organic group having 4-30 atoms.
Examples of the unsubstituted linear, branched or cyclic monovalent hydrocarbon group having 1 to 30 carbon atoms of R ⁵ , R ⁶ and R ⁷ include, for example, a methyl group, an ethyl group, an n-propyl group, i -Propyl group, n-butyl group, 1-methylpropyl group, 2-methylpropyl group, t-butyl group, n-pentyl group, i-pentyl group, 1,1-dimethylpropyl group, 1-methylbutyl group, 1 , 1-dimethylbutyl group, n-hexyl group, n-heptyl group, i-hexyl group, n-octyl group, i-octyl group, 2-ethylhexyl group, n-nonyl group, n-decyl group, n-undecyl Group, n-dodecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, 4-t-butylcyclohexyl group and other alkyl groups, cyclohexenyl group, group having norbornene skeleton, norbornane skeleton , A group having an isobornyl skeleton, a group having a tricyclodecane skeleton, a group having a tetracyclododecane skeleton, a group having an adamantane skeleton, and the like.
Examples of the substituent of the hydrocarbon group include an aryl group having 6 to 30 carbon atoms, a linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms, a halogen atom, an oxygen atom, and a nitrogen atom. , Groups having 1 to 30 atoms including heteroatoms such as sulfur atom, phosphorus atom and silicon atom. In addition, these substituents can further have one or more arbitrary substituents, for example, the above-described substituents.

  Examples of the linear, branched or cyclic monovalent hydrocarbon group having 1 to 30 carbon atoms substituted with the above substituent include, for example, benzyl group, methoxymethyl group, methylthiomethyl group, ethoxymethyl group, phenoxymethyl. Group, methoxycarbonylmethyl group, ethoxycarbonylmethyl group, acetylmethyl group, fluoromethyl group, trifluoromethyl group, chloromethyl group, trichloromethyl group, 2-fluoropropyl group, (trifluoroacetyl) methyl group, (trichloroacetyl group) ) Methyl group, (pentafluorobenzoyl) methyl group, aminomethyl group, (cyclohexylamino) methyl group, (diphenylphosphino) methyl group, (trimethylsilyl) methyl group, 2-phenylethyl group, 3-phenylpropyl group, 2 -An aminoethyl group etc. are mentioned.

Examples of the substituted or unsubstituted aryl group having 6 to 30 carbon atoms include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, and a 1-phenanthryl group.
Examples of the substituted or unsubstituted monovalent heterocyclic organic group having 4 to 30 atoms include a furyl group, a thienyl group, a pyranyl group, a pyrrolyl group, a thiantenyl group, a pyrazolyl group, an isothiazolyl group, an isoxazolyl group, a pyrazinyl group, Examples include a pyrimidinyl group, a pyridazinyl group, a terahydrohydropyranyl group, a tetrahydrofuranyl group, a tetrahydrothiopyranyl group, a tetrahydrothiofuranyl group, and a 3-tetrahydrothiophene-1,1-dioxide group.
Examples of the substituent for the aryl group and the monovalent heterocyclic organic group include linear, branched or cyclic alkyl groups having 1 to 30 carbon atoms, halogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, Examples thereof include groups having 1 to 30 atoms containing heteroatoms such as phosphorus atoms and silicon atoms. In addition, these substituents can further have one or more arbitrary substituents, for example, the above-described substituents.

Examples of the aryl group having 6 to 30 carbon atoms substituted with the above substituent include o-tolyl group, m-tolyl group, p-tolyl group, p-hydroxyphenyl group, p-methoxyphenyl group, mesityl group, o- Cumenyl group, 2,3-xylyl group, 2,4-xylyl group, 2,5-xylyl group, 2,6-xylyl group, 3,4-xylyl group, 3,5-xylyl group, p-fluorophenyl group , P-trifluoromethylphenyl group, p-bromophenyl group, p-chlorophenyl group, p-iodophenyl group, and the like.
Examples of the substituted monovalent heterocyclic organic group having 4 to 30 carbon atoms include, for example, 2-bromofuryl group, 3-methoxythienyl group, 3-bromotetrahydropyranyl group, 4-methoxytetrahydropyranyl group, 4-methoxytetrahydrothiopyranyl group etc. are mentioned.
In the formula (1), R ¹ can be bonded to any of the carbon atoms constituting the norbornane ring in the formula (excluding the carbon atom to which R ² , R ³ and R ⁴ are bonded). R ¹ present may be the same as or different from each other, and when R ¹ is included in the norbornane structure, they may form a ring together with the carbon atom, or any two of R ¹ may be present. The above R ¹ may be bonded to each other to form a ring.

Examples of the linear, branched, or cyclic alkyl group having 1 to 30 carbon atoms of R ² , R ^3, and R ⁴ include, for example, the above-described unsubstituted C 1-30 carbon atoms of R ⁵ , R ^6, and R ^7. Examples include the same groups as the alkyl groups exemplified for the chain, branched or cyclic monovalent hydrocarbon groups, and these may be the same or different.

In the formula (1), as R ¹ , for example, —R ⁵ , —COOR ⁶ , —SR ⁶ , —SOR ⁶ , —SO ₂ R ^6, —SO ₂ (OR ⁶ ) and the like are preferable. Specifically, —CH ₃ , —COOCH ₃ , —SCH ₃ , —SOCH ₃ , —SO ₂ CH ₃ , —SO ₂ (OCH ₃ ) may be mentioned.
R ² , R ³ and R ⁴ are each preferably, for example, a hydrogen atom or a linear or branched alkyl group having 1 to 5 carbon atoms, particularly a hydrogen atom, a methyl group, an ethyl group or a propyl group. Is preferred.
K is preferably an integer of 0 to 3, and n is preferably an integer of 0 or 1.

上記構造の中で、特に式（Ｓ−１）、式（Ｓ−７）、式（Ｓ−１４）または式（Ｓ−２０）で表される化学構造が好ましい。 Specific examples of the formula (1) excluding the onium cation (M ⁺ ) include chemical structures represented by the following formulas (S-1) to (S-25).

Among the above structures, a chemical structure represented by formula (S-1), formula (S-7), formula (S-14) or formula (S-20) is particularly preferable.

式（２）において、Ｒ⁵、Ｒ⁶およびＲ⁷は相互に独立に置換もしくは非置換の炭素数１〜１０の直鎖状もしくは分岐状のアルキル基または置換もしくは非置換の炭素数６〜１８のアリール基を表すか、あるいはＲ⁵、Ｒ⁶およびＲ⁷のうちの何れか２つ以上が相互に結合して式中のイオウ原子と共に環を形成している。

式（３）において、Ｒ⁸およびＲ⁹は相互に独立に置換もしくは非置換の炭素数１〜１０の直鎖状もしくは分岐状のアルキル基または置換もしくは非置換の炭素数６〜１８のアリール基を表すか、あるいはＲ⁸およびＲ⁹が相互に結合して式中のヨウ素原子と共に環を形成している。 M ⁺ represents a monovalent onium cation. As the monovalent onium cation, for example, onium cations such as O, S, Se, N, P, As, Sb, Cl, Br, and I are preferable.
Of these onium cations, S and I onium cations are preferred.
In the formula (1), examples of the M ⁺ monovalent onium cation include those represented by the following formula (2) or formula (3).

In the formula (2), R ⁵ , R ⁶ and R ⁷ are each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms or a substituted or unsubstituted carbon group having 6 to 18 carbon atoms. Or any two or more of R ⁵ , R ⁶ and R ⁷ are bonded to each other to form a ring together with the sulfur atom in the formula.

In formula (3), R ⁸ and R ⁹ are each independently 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. Or R ⁸ and R ⁹ are bonded to each other to form a ring together with the iodine atom in the formula.

The monovalent onium cation moiety represented by M ⁺ can be produced according to a known method described in, for example, Advances in Polymer Sciences, Vol. 62, p. 1-48 (1984).
Preferred monovalent onium cations include, for example, sulfonium cations represented by the following formulas (2-1) to (2-64) and iodonium cations represented by the following formulas (3-1) to (3-39). Etc.

  Among these monovalent onium cations, for example, Formula (2-1), Formula (2-2), Formula (2-6), Formula (2-8), Formula (2-13), Formula (2) -19), a formula (2-25), a formula (2-27), a formula (2-29), a formula (2-30), a sulfonium cation represented by the formula (2-31); formula (3-1) ) Or an iodonium cation represented by the formula (3-11) is preferable.

In the present invention, an acid generator having the structure of formula (1) and a compound that generates an acid upon irradiation with EB and EUV other than the acid generator (hereinafter referred to as “other acid generator”). Can be used together.
Other acid generators include onium salts other than acid generators having the structure of formula (1), N-sulfonyloxyimide compounds, diazomethane compounds, oxime sulfonate compounds, etc., but sulfonyl salts, iodonium salts or Compounds that generate trifluoromethanesulfonate, nonafluoro-n-butanesulfonate, 10-camphorsulfonate, and p-toluenesulfonate with N-sulfonyloxyimide compounds are preferred.
Specific examples of other acid generators include onium salts,
Bis (pt-butylphenyl) iodonium trifluoromethanesulfonate, bis (pt-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (pt-butylphenyl) iodonium o-trifluoromethylbenzenesulfonate, Bis (pt-butylphenyl) iodonium 10-camphor-sulfonate, bis (pt-butylphenyl) iodonium p-toluenesulfonate, bis (pt-butylphenyl) iodonium n-octanesulfonate,
Triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium o-trifluoromethylbenzenesulfonate, triphenylsulfonium p-trifluoromethylbenzenesulfonate, triphenylsulfonium 10-camphor-sulfonate, triphenylsulfonium o-trifluoromethylbenzenesulfonate Phenylsulfonium p-toluenesulfonate, triphenylsulfonium pyrenesulfonate, triphenylsulfonium n-dodecylbenzenesulfonate, triphenylsulfoniumbenzenesulfonate, triphenylsulfonium 2,4-difluorobenzenesulfonate, triphenylsulfonium n-octanesulfonate,
p-methylphenyldiphenylsulfonium trifluoromethanesulfonate, p-methylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, p-methylphenyldiphenylsulfonium o-trifluoromethylbenzenesulfonate, p-methylphenyldiphenylsulfonium p-trifluoromethylbenzene Sulfonate, p-methylphenyldiphenylsulfonium 10-camphor-sulfonate, p-methylphenyldiphenylsulfonium p-toluenesulfonate, p-methylphenyldiphenylsulfonium pyrenesulfonate, p-methylphenyldiphenylsulfonium n-dodecylbenzenesulfonate, p-methylphenyl Diphenylsulfonium benzenesulfonate, p-methylpheny Diphenylsulfonium 2,4-difluoro benzenesulfonate, p- methylphenyl sulfonium n- octane sulfonate,

pt-butylphenyldiphenylsulfonium trifluoromethanesulfonate, pt-butylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, pt-butylphenyldiphenylsulfonium o-trifluoromethylbenzenesulfonate, pt-butylphenyl Diphenylsulfonium p-trifluoromethylbenzenesulfonate, pt-butylphenyldiphenylsulfonium 10-camphor-sulfonate, pt-butylphenyldiphenylsulfonium p-toluenesulfonate, pt-butylphenyldiphenylsulfonium pyrenesulfonate, p- t-butylphenyldiphenylsulfonium n-dodecylbenzenesulfonate, pt-butylphenyldiphenylsulfonium base Zen sulfonate, p-t-butylphenyl diphenyl sulfonium 2,4-difluoro benzenesulfonate, p-t-butylphenyl diphenyl sulfonium n- octane sulfonate,
p-methoxyphenyldiphenylsulfonium trifluoromethanesulfonate, p-methoxyphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, p-methoxyphenyldiphenylsulfonium o-trifluoromethylbenzenesulfonate, p-methoxyphenyldiphenylsulfonium p-trifluoromethylbenzene Sulfonate, p-methoxyphenyldiphenylsulfonium 10-camphor-sulfonate, p-methoxyphenyldiphenylsulfonium p-toluenesulfonate, p-methoxyphenyldiphenylsulfonium pyrenesulfonate, p-methoxyphenyldiphenylsulfonium n-dodecylbenzenesulfonate, p-methoxyphenyl Diphenylsulfonium benzene sulfonate p- methoxyphenyl diphenyl sulfonium 2,4-difluoro benzenesulfonate, p- methoxyphenyl diphenyl sulfonium n- octane sulfonate,
pt-butoxyphenyldiphenylsulfonium trifluoromethanesulfonate, pt-butoxyphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, pt-butoxyphenyldiphenylsulfonium o-trifluoromethylbenzenesulfonate, pt-butoxyphenyl Phenyldiphenylsulfonium p-trifluoromethylbenzenesulfonate, pt-butoxyphenyldiphenylsulfonium 10-camphor-sulfonate, pt-butoxyphenyldiphenylsulfonium p-toluenesulfonate, pt-butoxyphenyldiphenylsulfonium pyrenesulfonate, p -T-butoxyphenyldiphenylsulfonium n-dodecylbenzenesulfonate, pt-butoxypheny Diphenylsulfonium benzenesulfonate, p-t-butoxyphenyl diphenylsulfonium 2,4-difluoro benzenesulfonate, p-t-butoxyphenyl diphenylsulfonium n- octane sulfonate,
Tris (4-methoxyphenyl) sulfonium trifluoromethanesulfonate, tris (4-methoxyphenyl) sulfonium nonafluoro-n-butanesulfonate, tris (4-methoxyphenyl) sulfonium sulfonium o-trifluoromethylbenzenesulfonate, tris (4-methoxy Phenyl) sulfonium sulfonium sulfonium p-trifluoromethylbenzenesulfonate, tris (4-methoxyphenyl) sulfonium sulfoniumsulfonium sulfonium 10-camphor-sulfonate, tris (4-methoxyphenyl) sulfonium p-toluenesulfonate, tris (4-methoxyphenyl) Examples include sulfonium n-octane sulfonate.

Specific examples of the N-sulfonyloxyimide compound include
N- (trifluoromethylsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) diphenylmaleimide, N- (trifluoromethylsulfonyloxy) bicyclo [2.2.1 ] Hept-5-ene-2,3-dicarboximide, N- (trifluoromethylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (trifluoromethylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (trifluoromethylsulfonyloxy) naphthylimide,
N- (10-camphorsulfonyloxy) succinimide, N- (10-camphorsulfonyloxy) phthalimide, N- (10-camphorsulfonyloxy) diphenylmaleimide, N- (10-camphorsulfonyloxy) bicyclo [2.2.1 ] Hept-5-ene-2,3-dicarboximide, N- (10-camphorsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (10-camphorsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (10-camphorsulfonyloxy) naphthylimide,

N- (p-methylphenylsulfonyloxy) succinimide, N- (p-methylphenylsulfonyloxy) phthalimide, N- (p-methylphenylsulfonyloxy) diphenylmaleimide, N- (p-methylphenylsulfonyloxy) bicyclo [2 2.1] hept-5-ene-2,3-dicarboximide, N- (p-methylphenylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3 -Dicarboximide, N- (p-methylphenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (p-methylphenylsulfonyloxy) naphthyl Imide,
N- (o-trifluoromethylphenylsulfonyloxy) succinimide, N- (o-trifluoromethylphenylsulfonyloxy) phthalimide, N- (o-trifluoromethylphenylsulfonyloxy) diphenylmaleimide, N- (o-trifluoro Methylphenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (o-trifluoromethylphenylsulfonyloxy) -7-oxabicyclo [2.2.1 ] Hept-5-ene-2,3-dicarboximide, N- (o-trifluoromethylphenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide N- (o-trifluoromethylphenylsulfonyloxy) naphthylimide,

N- (p-fluorophenylsulfonyloxy) succinimide, N- (p-fluorophenylsulfonyloxy) phthalimide, N- (p-fluorophenylsulfonyloxy) diphenylmaleimide, N- (p-fluorophenylsulfonyloxy) bicyclo [2 2.1] hept-5-ene-2,3-dicarboximide, N- (p-fluorophenylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3 -Dicarboximide, N- (p-fluorophenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide, N- (p-fluorophenylsulfonyloxy) naphthyl An imide etc. can be mentioned.

Specific examples of diazomethane compounds include
Bis (trifluoromethylsulfonyl) diazomethane, bis (t-butylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (phenylsulfonyl) diazomethane, bis (p-methylphenylsulfonyl) diazomethane, bis (1,4-dioxaspiro [ 4.5] decane-7-sulfonyl) diazomethane, bis (1,5-dioxaspiro [5.5] undecan-8-sulfonyl) diazomethane, bis (3,3-dimethyl-1,5-dioxaspiro [5.5] Undecane-8-sulfonyl) diazomethane,
Methylsulfonyl cyclohexylsulfonyldiazomethane, methylsulfonyl phenylsulfonyldiazomethane, methylsulfonyl p-methylphenylsulfonyldiazomethane, t-butylsulfonyl cyclohexylsulfonyldiazomethane, t-butylsulfonyl phenylsulfonyldiazomethane, t-butylsulfonyl p-methyl Phenylsulfonyldiazomethane,
Cyclohexylsulfonyl 1,4-dioxaspiro [4.5] decane-7-sulfonyldiazomethane, cyclohexylsulfonyl-1,5-dioxaspiro [5.5] undecane-8-sulfonyldiazomethane, cyclohexylsulfonyl 3,3-dimethyl-1 , 5-dioxaspiro [5.5] undecane-8-sulfonyldiazomethane and the like.

As a specific example of the oxime sulfonate compound,
(5-n-propylsulfonyloxyimino-5H-thiophen-2-indene) (2-methylpheninone) acetonitrile, 2,2,2-trifluoro-1- {4- (3- [4- {2, 2,2-trifluoro-1- (1-n-propanesulfonyloxyimino) ethyl} phenoxy] n-propoxy) phenyl} ethaneoxime 1-n-propanesulfonate and the like.
Among the other acid generators, sulfonium salts, iodonium salts, and N-sulfonyloxyimide compounds are preferable.

  The acid generator having the structure of the formula (1) is contained at least 5% by weight with respect to the whole acid generator (acid generator having the structure of the formula (1) + other acid generator). If it is less than 5% by weight, the resolution during pattern formation tends to be difficult to be 90 nm or less.

  The compounding amount of the acid generator in the positive radiation-sensitive resin composition is usually 2 to 35% by weight, preferably 4 to 30%, based on the alkali-insoluble or alkali-insoluble resin that becomes alkali-soluble when the acid-dissociable group is dissociated. % By weight, more preferably 5 to 25% by weight. When the amount of the acid generator used is less than 2% by weight, the resolution and the line edge roughness are lowered. On the other hand, when it exceeds 35% by weight, the resist coating property, pattern shape, heat resistance, etc. may be lowered.

Acid-dissociable resin An alkali-insoluble or alkali-insoluble resin having an acid-dissociable group is a resin having one or more oxygen-containing functional groups such as a phenolic hydroxyl group, an alcoholic hydroxyl group, and a carboxyl group. A hydrogen atom is substituted with one or more acid-dissociable groups that can dissociate in the presence of an acid, which is itself an alkali-insoluble or alkali-insoluble resin, and the acid-dissociable group is dissociated. Sometimes it becomes alkali-soluble resin.
The term “alkali insoluble or alkali poorly soluble” as used herein refers to alkali development conditions employed when forming a resist pattern from a resist film formed using a positive resist composition containing an acid-dissociable group-containing resin. Below, when a film using only an acid-dissociable group-containing resin instead of the resist film is developed, it means that 50% or more of the initial film thickness of the film remains after development.

Examples of the acid dissociable group in the acid dissociable group-containing resin include a substituted methyl group, a 1-substituted ethyl group, a 1-substituted-n-propyl group, a 1-branched alkyl group, a silyl group, a germyl group, and an alkoxycarbonyl. Group, acyl group, cyclic acid dissociable group and the like.
Examples of the substituted methyl group include methoxymethyl group, methylthiomethyl group, ethoxymethyl group, ethylthiomethyl group, methoxyethoxymethyl group, benzyloxymethyl group, benzylthiomethyl group, phenacyl group, 4-bromophenacyl group, 4 -Methoxyphenacyl group, 4-methylthiophenacyl group, α-methylphenacyl group, cyclopropylmethyl group, benzyl group, diphenylmethyl group, triphenylmethyl group, adamantylmethyl group, 4-bromobenzyl group, 4-nitro Benzyl group, 4-methoxybenzyl group, 4-methylthiobenzyl group, 4-ethoxybenzyl group, 4-ethylthiobenzyl group, piperonyl group, methoxycarbonylmethyl group, ethoxycarbonylmethyl group, n-propoxycarbonylmethyl group, i- Propoxycarbo Rumechiru group, n- butoxycarbonyl methyl group, and the like t- butoxycarbonyl methyl group.
Examples of the 1-substituted ethyl group include 1-methoxyethyl group, 1-methylthioethyl group, 1,1-dimethoxyethyl group, 1-ethoxyethyl group, 1-ethylthioethyl group, 1,1- Diethoxyethyl group, 1-phenoxyethyl group, 1-phenylthioethyl group, 1,1-diphenoxyethyl group, 1-benzyloxyethyl group, 1-benzylthioethyl group, 1-cyclopropyloxyethyl group, 1 -Cyclohexyloxyethyl group, 1-phenylethyl group, 1,1-diphenylethyl group, 1-methoxycarbonylethyl group, 1-ethoxycarbonylethyl group, 1-n-propoxycarbonylethyl group, 1-i-propoxycarbonylethyl Group, 1-n-butoxycarbonylethyl group, 1-t-butoxycarbonylethyl group, 1-cyclo Like hexyl butyloxycarbonylethyl group.

Examples of the 1-substituted-n-propyl group include a 1-methoxy-n-propyl group and a 1-ethoxy-n-propyl group.
Examples of the 1-branched alkyl group include i-propyl group, sec-butyl group, t-butyl group, 1,1-dimethylpropyl group, 1-methylbutyl group, 1,1-dimethylbutyl group, and the like. Can be mentioned.
Examples of the silyl group include trimethylsilyl group, ethyldimethylsilyl group, methyldiethylsilyl group, triethylsilyl group, i-propyldimethylsilyl group, methyldi-i-propylsilyl group, tri-i-propylsilyl group, Examples thereof include a t-butyldimethylsilyl group, a methyldi-t-butylsilyl group, a tri-t-butylsilyl group, a phenyldimethylsilyl group, a methyldiphenylsilyl group, and a triphenylsilyl group.
Examples of the germyl group include a trimethylgermyl group, an ethyldimethylgermyl group, a methyldiethylgermyl group, a triethylgermyl group, an i-propyldimethylgermyl group, a methyldi-i-propylgermyl group, and a trimethylgermyl group. -I-propylgermyl group, t-butyldimethylgermyl group, methyldi-t-butylgermyl group, tri-t-butylgermyl group, phenyldimethylgermyl group, methyldiphenylgermyl group, triphenylgermyl group, etc. It is done.
Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, an i-propoxycarbonyl group, and a t-butoxycarbonyl group.

Examples of the acyl group include acetyl group, propionyl group, butyryl group, heptanoyl group, hexanoyl group, valeryl group, pivaloyl group, isovaleryl group, laurylyl group, myristoyl group, palmitoyl group, stearoyl group, oxalyl group, malonyl Group, succinyl group, glutaryl group, adipoyl group, piperoyl group, suberoyl group, azelaoil group, sebacoyl group, acryloyl group, propioyl group, methacryloyl group, crotonoyl group, oleoyl group, maleoyl group, fumaroyl group, mesaconoyl group, canphoroyl group Benzoyl group, phthaloyl group, isophthaloyl group, terephthaloyl group, naphthoyl group, toluoyl group, hydroatropoyl group, atropoyl group, cinnamoyl group, furoyl group, thenoyl group, nicotinoyl group Isonicotinoyl group, p- toluenesulfonyl group, mesyl group, and the like.
Further, examples of the cyclic acid dissociable group include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a 4-t-butylcyclohexyl group, a 4-methoxycyclohexyl group, a cyclohexenyl group, a norbornyl group, an isobornyl group, and a tricyclo group. Decanyl group, adamantyl group, tetrahydropyranyl group, tetrahydrofuranyl group, tetrahydrothiopyranyl group, tetrahydrothiofuranyl group, 3-bromotetrahydropyranyl group, 4-methoxytetrahydropyranyl group, 4-methoxytetrahydrothiopyrani Group, 3-tetrahydrothiophene-1,1-dioxide group, methyladamantyl group, ethyladamantyl group, methyltricyclodecanyl group, ethyltricyclodecanyl group, methylcyclopentyl group, ethylcyclopentyl group, Le cyclohexyl group, an ethyl cyclohexyl group, -C (R) ₃ group, and the like. In the -C (R) ₃ group, each R is independently a linear or branched alkyl group having 1 to 4 carbon atoms or a monovalent alicyclic carbon atom having 4 to 20 carbon atoms which may be substituted. Each represents a hydrogen group and at least one R is a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms which may be substituted, or any two Rs are bonded to each other, A divalent alicyclic hydrocarbon group having 4 to 20 carbon atoms which may be substituted is formed together with the bonded carbon atom, and the remaining R is a linear or branched alkyl having 1 to 4 carbon atoms. Or a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms which may be substituted.

Among these acid dissociable groups, benzyl group, t-butoxycarbonylmethyl group, 1-methoxyethyl group, 1-ethoxyethyl group, 1-cyclohexyloxyethyl group, 1-ethoxy-n-propyl group, t-butyl Group, 1,1-dimethylpropyl group, trimethylsilyl group, t-butoxycarbonyl group, 4-t-butylcyclohexyl group, isobornyl group, tricyclodecanyl group, tetrahydropyranyl group, tetrahydrofuranyl group, tetrahydrothiopyranyl group , Tetrahydrothiofuranyl group, methyladamantyl group, ethyladamantyl group, methyltricyclodecanyl group, ethyltricyclodecanyl group, methylcyclopentyl group, ethylcyclopentyl group, methylcyclohexyl group, ethylcyclohexyl group, -C (R) _Three groups are preferred.
Specific examples of preferred group -C (R) ₃ include 1- (2-norbornyl) -1-methylethyl group, 1- (5-hydroxy-2-norbornyl) -1-methylethyl group, 1- (3 -Tetracyclodecanyl) -1-methylethyl group, 1- (8-hydroxy-3-tetracyclodecanyl) -1-methylethyl group, 1- (1-adamantyl) -1-methylethyl group, 1- (3-hydroxy-1-adamantyl) -1-methylethyl group, 2-methyl-2-norbornyl group, 2-methyl-5-hydroxy-2-norbornyl group, 3-methyl-3-tetracyclodecanyl group, Examples include 3-methyl-8-hydroxy-3-tetracyclodecanyl group, 2-methyl-2-adamantyl group, 2-methyl-7-hydroxy-2-adamantyl group and the like.

  The rate of introduction of acid dissociable groups in the acid dissociable group-containing resin (ratio of the number of acid dissociable groups to the total number of oxygen-containing functional groups and acid dissociable groups in the acid dissociable group-containing resin) Although it cannot be generally defined by the type of the dissociable group or the alkali-soluble resin into which the group is introduced, it is preferably 10 to 70%, more preferably 10 to 50%.

The polystyrene-reduced weight molecular weight (hereinafter referred to as “Mw”) of the acid-dissociable group-containing resin measured by gel permeation chromatography is preferably 1,000 to 100,000, more preferably 3,000 to 50,000, More preferably, it is 5,000-3,000.
Further, the ratio (Mw / Mn) of Mw of the acid-dissociable group-containing resin and polystyrene-reduced number molecular weight (hereinafter referred to as “Mn”) measured by gel permeation chromatography (GPC) is usually 1 to 5, Preferably it is 1-3, More preferably, it is 1.0-2.0.
The acid dissociable group-containing resins can be used alone or in admixture of two or more.

式（４）において、Ｒ¹⁰は水素原子または１価の有機基を示し、ｅおよびｆはそれぞれ１〜３の整数で、（ｅ＋ｆ）≦５である。
式（４）で表される繰り返し単位としては、４−ヒドロキシスチレン、３−ヒドロキシスチレン、２−ヒドロキシスチレン、４−ヒドロキシ−α−メチルスチレン、３−メチル−４−ヒドロキシスチレン、２−メチル−４−ヒドロキシスチレン、２−メチル−３−ヒドロキシスチレン、４−メチル−３−ヒドロキシスチレン、５−メチル−３−ヒドロキシスチレン、３，４−ジヒドロキシスチレン、２，４，６−トリヒドロキシスチレン等の重合性不飽和結合が開裂した単位が挙げられる。
これらの繰り返し単位のうち、４−ヒドロキシスチレン、３−ヒドロキシスチレン、２−ヒドロキシスチレン、４−ヒドロキシ−α−メチルスチレン等の重合性不飽和結合が開裂した単位が好ましい。 The acid-dissociable group-containing resin particularly preferably used for the positive radiation-sensitive resin composition includes at least one repeating unit represented by the following formula (4) and a repeating unit having the acid-dissociable group. An alkali-insoluble or hardly alkali-soluble resin having at least one kind is preferred.

In the formula (4), R ¹⁰ represents a hydrogen atom or a monovalent organic group, e and f are each an integer of 1 to 3, and (e + f) ≦ 5.
As the repeating unit represented by the formula (4), 4-hydroxystyrene, 3-hydroxystyrene, 2-hydroxystyrene, 4-hydroxy-α-methylstyrene, 3-methyl-4-hydroxystyrene, 2-methyl- Such as 4-hydroxystyrene, 2-methyl-3-hydroxystyrene, 4-methyl-3-hydroxystyrene, 5-methyl-3-hydroxystyrene, 3,4-dihydroxystyrene, 2,4,6-trihydroxystyrene, etc. Examples include a unit in which a polymerizable unsaturated bond is cleaved.
Of these repeating units, units having a polymerizable unsaturated bond cleaved such as 4-hydroxystyrene, 3-hydroxystyrene, 2-hydroxystyrene, 4-hydroxy-α-methylstyrene are preferred.

  As the repeating unit having an acid dissociable group, a repeating unit containing one or more acidic functional groups such as a phenolic hydroxyl group and a carboxyl group, preferably a repeating unit represented by formula (4) or (meth) acrylic Examples thereof include a unit in which a hydrogen atom of a phenolic hydroxyl group or a carboxyl group in a repeating unit in which a polymerizable unsaturated bond of an acid is cleaved is substituted with the acid dissociable group. Specifically, 4-t-butoxystyrene, 4-t-butoxycarbonyloxystyrene, 4-t-butoxycarbonylmethyloxystyrene, 4-tetrahydrofuranyloxystyrene, 4-tetrahydropyranyloxystyrene, 2-ethoxyethoxy Styrene, t-butyl (meth) acrylate, methyladamantyl (meth) acrylate, ethyladamantyl (meth) acrylate, methylcyclopentyl (meth) acrylate, ethylcyclopentyl (meth) acrylate, methylcyclohexyl (meth) acrylate, ethylcyclohexyl (meth) Examples include units in which a polymerizable unsaturated bond such as acrylate is cleaved.

In addition, the acid dissociable resin can have one or more kinds of repeating units other than those described above.
As other repeating units, for example, styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-methoxystyrene, 3-methoxystyrene, 4-methoxystyrene, 4- (2 Vinyl aromatic compounds such as -t-butoxycarbonylethyloxy) styrene;
Methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, n-pentyl (meth) acrylate, N-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth ) (Meth) acrylic acid esters such as phenyl acrylate and phenethyl (meth) acrylate;
Unsaturated carboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, cinnamic acid;
Carboxyalkyl esters of unsaturated carboxylic acids such as 2-carboxyethyl (meth) acrylate, 2-carboxypropyl (meth) acrylate, 3-carboxypropyl (meth) acrylate;
Unsaturated nitrile compounds such as (meth) acrylonitrile, α-chloroacrylonitrile, crotonnitrile, maleinnitrile, fumaronitrile;
Unsaturated amide compounds such as (meth) acrylamide, N, N-dimethyl (meth) acrylamide, crotonamide, maleinamide, fumaramide;
Unsaturated imide compounds such as maleimide, N-phenylmaleimide, N-cyclohexylmaleimide;
N-vinyl-ε-caprolactam, N-vinyl pyrrolidone, 2-vinyl pyridine, 3-vinyl pyridine, 4-vinyl pyridine, 2-vinyl imidazole, other nitrogen-containing vinyl compounds such as 4-vinyl imidazole, etc. Examples include units in which a saturated bond is cleaved.
Of these other repeating units, styrene, α-methylstyrene, and 4- (2-t-butoxycarbonylethyloxy) styrene units are preferred.
In addition, a resin in which the hydrogen atom of the phenolic hydroxyl group of the cresol novolak resin is substituted with the acid dissociable group is preferably used as the positive-type radiation-sensitive resin composition as another acid-dissociable group-containing resin. it can. Preferable acid dissociable groups in this resin include, for example, ethoxyethyl group, t-butyl group, t-butoxycarbonyl group, t-butoxycarbonylmethyl group, methyladamantyl group, ethyladamantyl group and the like.

Other Components Alkali Dissolution Control Agent In the positive radiation sensitive resin composition of the present invention, the following alkali dissolution control agent can be blended in some cases.
Examples of the alkali dissolution control agent include compounds in which a hydrogen atom of an acidic functional group such as a phenolic hydroxyl group or a carboxyl group is substituted with an acid dissociable group or a t-butoxycarbonylmethyl group.
Examples of the acid dissociable group include a substituted methyl group, a 1-substituted ethyl group, a 1-substituted-n-propyl group, a 1-branched alkyl group exemplified for the acid dissociable group in the acid dissociable group-containing resin, Examples thereof include the same groups as silyl group, germyl group, alkoxycarbonyl group, acyl group, cyclic acid dissociable group and the like.

Examples of the alkali dissolution inhibitor in the positive radiation sensitive resin composition of the present invention include steroids (bile acids) such as cholic acid, deoxycholic acid, and lithocholic acid, and fats such as adamantane carboxylic acid and adamantane dicarboxylic acid. A compound in which a hydrogen atom of a carboxyl group in a carboxylic acid compound having a cyclic ring or an aromatic ring is substituted with the acid dissociable group or t-butoxycarbonylmethyl group is preferable.
The blending amount of the alkali solubility control agent in the positive radiation sensitive resin composition is 0.5 to 50 parts by weight, preferably 1 to 30 parts by weight, more preferably 2 to 2 parts by weight based on 100 parts by weight of the acid dissociable resin. 20 parts by weight.
Moreover, an alkali solubility control agent can be used individually or in mixture of 2 or more types.

The acid diffusion controller, the alkali-soluble resin for acid-dissociable resin, the surfactant, the sensitizer, and the solvent, which are other components blended in the radiation-sensitive resin composition, will be described.
Acid diffusion control agent The radiation-sensitive resin composition controls the diffusion phenomenon in the resist film of the acid generated from the acid generator by irradiation with an electron beam or radiation having a wavelength of 140 nm or less, which is not preferable in a non-irradiated region. It is preferable to add an acid diffusion controller having an action of suppressing a chemical reaction.
By using such an acid diffusion control agent, the storage stability of the composition is improved, the resolution is improved as a resist, and due to fluctuations in the holding time (PED) from irradiation to heat treatment after irradiation. Changes in the line width of the resist pattern can be suppressed, and the process stability is extremely excellent.

式（５）において、各Ｒ¹¹は相互に独立に水素原子、アルキル基、アリール基またはアラルキル基を示し、これらの基は例えばヒドロキシ基等の官能基で置換されていてもよい。 As the acid diffusion controller, a nitrogen-containing organic compound whose basicity is not changed by radiation irradiation or heat treatment in the resist pattern forming step is preferable.
As such a nitrogen-containing organic compound, for example, a compound represented by the following formula (5) (hereinafter referred to as “nitrogen-containing compound (α))”, a diamino compound having two nitrogen atoms in the same molecule ( Hereinafter, referred to as “nitrogen-containing compound (β)”), diamino polymer having 3 or more nitrogen atoms (hereinafter referred to as “nitrogen-containing compound (γ)”), amide group-containing compound, urea compound, nitrogen-containing complex. A ring compound etc. are mentioned.

In the formula (5), each R ¹¹ independently represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and these groups may be substituted with a functional group such as a hydroxy group.

Examples of the nitrogen-containing compound (α) include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; di-n-butylamine, di-n- Dialkylamines such as pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decylamine; triethylamine, tri-n-propylamine, Trialkylamines such as tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine Aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methyl Ruanirin, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenylamine, aromatic amines such as 1-naphthylamine, and the like.
Examples of the nitrogen-containing compound (β) include ethylenediamine, N, N, N ′,
N′-tetramethylethylenediamine, N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 4,4′-diaminobenzophenone, 4,4′-diaminodiphenylamine, 2,2′-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 2 -(4-aminophenyl) -2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) propane, 1,4-bis [1- (4-aminophenyl) ) -1-Methylethyl] benzene, 1,3-bis [1- (4-aminophenyl) -1-methylethyl Benzene, and the like.
Examples of the nitrogen-containing compound (γ) include polymers of polyethyleneimine, polyallylamine, dimethylaminoethylacrylamide, and the like.
Examples of the amide group-containing compound include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone and the like. Is mentioned.
Examples of the urea compound include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tributylthiourea and the like. It is done.

Examples of the nitrogen-containing heterocyclic compound include imidazoles such as imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, benzimidazole, 2-phenylbenzimidazole; pyridine, 2-methylpyridine, 4-methyl. Such as pyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, N-methyl-4-phenylpyridine, nicotine, nicotinic acid, nicotinamide, quinoline, 8-oxyquinoline, acridine, etc. In addition to pyridines, pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, morpholine, 4-methylmorpholine, piperazine, 1,4-dimethylpiperazine, 1,4-diazabicyclo [2.2.2] octane, phenanthro Emissions, and the like.
Moreover, the nitrogen-containing compound which has an acid dissociable group can also be used as said nitrogen-containing organic compound.
Examples of the nitrogen-containing compound having an acid dissociable group include N- (t-butoxycarbonyl) piperidine, N- (t-butoxycarbonyl) imidazole, N- (t-butoxycarbonyl) benzimidazole, N- (t -Butoxycarbonyl) 2-phenylbenzimidazole, N- (t-butoxycarbonyl) dioctylamine, N- (t-butoxycarbonyl) diethanolamine, N- (t-butoxycarbonyl) dicyclohexylamine, N- (t-butoxycarbonyl) diphenylamine Etc.

Of these nitrogen-containing organic compounds, nitrogen-containing compounds (α), nitrogen-containing compounds (β), nitrogen-containing heterocyclic compounds, nitrogen-containing compounds having an acid-dissociable group, and the like are preferable.
The acid diffusion control agents can be used alone or in admixture of two or more.
The compounding amount of the acid diffusion controller is usually 15 parts by weight or less, preferably 0.001 to 10 parts by weight, per 100 parts by weight of the alkali-soluble resin in the acid-dissociable group-containing resin in the positive radiation sensitive resin composition. More preferably, it is 0.005-5 weight part. In this case, when the compounding amount of the acid diffusion controller exceeds 15 parts by weight, the sensitivity as a resist and the developability of the irradiated part tend to decrease. If the amount of the acid diffusion controller is less than 0.001 part by weight, the pattern shape and dimensional fidelity as a resist may be lowered depending on the process conditions.

Surfactant A surfactant exhibiting an effect of improving the coatability and striation of the radiation-sensitive resin composition, the developability as a resist, and the like can be blended.
Examples of such surfactants include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octylphenol ether, polyoxyethylene n-nonylphenol ether, polyethylene glycol dilaurate, polyethylene glycol dilaurate. Examples of commercially available products include F-top EF301, EF303, EF352 (manufactured by Tochem Products), Megafax F171, F173 (above, Dainippon Ink & Chemicals, Inc.) )), Fluorad FC430, FC431 (above, manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, the SC105, the SC106 (manufactured by Asahi Glass Co., Ltd.), KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, no. 95 (manufactured by Kyoeisha Chemical Co., Ltd.).
These surfactants can be used alone or in admixture of two or more.
The blending amount of the surfactant is preferably 2 parts by weight or less per 100 parts by weight of the acid-dissociable group-containing resin in the positive radiation sensitive resin composition.

Sensitizer A sensitizer can be mix | blended with a radiation sensitive resin composition. Preferred sensitizers include, for example, carbazoles, benzophenones, rose bengals, anthracene and the like.
These sensitizers can be used alone or in admixture of two or more. The amount of the sensitizer is preferably 50 parts by weight or less per 100 parts by weight of the acid-dissociable group-containing resin in the positive resist composition.

Solvent The radiation-sensitive resin composition is dissolved in a solvent so that the concentration of the total solid content is usually 0.1 to 50% by weight, preferably 1 to 30% by weight. For example, it is prepared as a composition solution by filtering with a filter having a pore size of about 0.2 μm.
Examples of the solvent used for the preparation of the composition solution include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, ethylene glycol mono-n-butyl ether acetate and the like. Glycol monoalkyl ether acetates;
Propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether;
Propylene glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol di-n-propyl ether, propylene glycol di-n-butyl ether;
Propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol mono-n-butyl ether acetate;
Lactate esters such as methyl lactate, ethyl lactate, n-propyl lactate, i-propyl lactate;
N-amyl formate, i-amyl formate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, n-amyl acetate, i-amyl acetate, i-propyl propionate Aliphatic carboxylic acid esters such as n-butyl propionate and i-butyl propionate;
Ethyl hydroxyacetate, ethyl 2-hydroxy-2-methylpropionate, methyl 2-hydroxy-3-methylbutyrate, ethyl methoxyacetate, ethyl ethoxyacetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3-ethoxy Methyl propionate, ethyl 3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, 3-methyl-3-methoxybutyl butyrate, Other esters such as methyl acetoacetate, ethyl acetoacetate, methyl pyruvate, ethyl pyruvate;
Aromatic hydrocarbons such as toluene and xylene;
Ketones such as methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, 2-heptanone, 3-heptanone, 4-heptanone, cyclohexanone;
Amides such as N-methylformamide, N, N-dimethylformamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone;
Examples include lactones such as γ-butyrolacun.
These solvents can be used alone or in admixture of two or more.

Formation of resist pattern When forming a resist pattern from a radiation-sensitive resin composition, the composition solution prepared as described above is applied by appropriate application means such as spin coating, cast coating, roll coating, etc. For example, it is applied onto a substrate such as a silicon wafer or a wafer coated with aluminum, and in some cases, a heat treatment (hereinafter referred to as “PB”) is performed at a temperature of about 70 ° C. to 160 ° C. to form a resist film. After that, drawing is performed by irradiating with radiation, preferably an electron beam. The drawing conditions are appropriately selected according to the composition of the radiation sensitive resin composition, the type of each additive, and the like.

In the present invention, in order to stably form a high-precision fine pattern, a heat treatment (hereinafter referred to as “PEB”) is performed at a temperature of 50 to 200 ° C., preferably 70 to 160 ° C. for 30 seconds or more after irradiation. ) Is preferable. In this case, when the temperature of the PEB is less than 50 ° C., there is a possibility that the variation in sensitivity depending on the type of the substrate is widened.
Then, a predetermined resist pattern is formed by developing with an alkali developer usually at 10 to 50 ° C. for 10 to 200 seconds, preferably at 15 to 30 ° C. for 15 to 100 seconds.
Examples of the alkali developer include alkali metal hydroxide, aqueous ammonia, mono-, di- or tri-alkylamines, mono-, di- or tri-alkanolamines, heterocyclic amines, and tetraalkyls. Alkaline compounds such as ammonium hydroxides, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene, 1,5-diazabicyclo- [4.3.0] -5-nonene are usually used. An alkaline aqueous solution dissolved so as to have a concentration of 1 to 10% by weight, preferably 1 to 5% by weight, particularly preferably 1 to 3% by weight is used.
In addition, a water-soluble organic solvent such as methanol or ethanol or a surfactant can be appropriately added to the developer composed of the alkaline aqueous solution.
In forming the resist pattern, a protective film or an antistatic film can be provided on the resist film in order to prevent the influence of basic impurities contained in the environmental atmosphere and the charge in the film.

Hereinafter, the present invention will be described more specifically with reference to examples. Here,% and parts are based on weight unless otherwise specified.
Mass analysis of the following acid generators (A-1) and (A-2) was performed under the following conditions.
Apparatus: JMS-AX505W type mass spectrometer manufactured by JEOL Ltd. Emitter current: 5 mA (used gas: Xe)
Acceleration voltage: 3.0 kV
10N MULTI: 1.3
Ionization method: Fast atom bombardment method (FAB)
Detection ion: Cation (+)
Measurement mass range: 20-1500 m / z
Scan: 30 seconds Resolution: 1500
Matrix: 3-nitrobenzyl alcohol In addition, ¹ H-NMR analysis of acid generators (A-1) and (A-2) uses “JNM-EX270” manufactured by JEOL Ltd., and CDCl ₃ is used as a measurement solvent. Carried out using.

Synthesis Example 1: Synthesis of acid generator (A-1) 69.6 g of sodium dithionite and 50.4 g of sodium hydrogen carbonate were placed in a 2-liter three-necked flask sufficiently purged with nitrogen, and dimethyl sulfoxide was obtained at room temperature. 600 ml and 47.8 g of 1-bromo-1,1-difluoro-2- (bicyclo [2.2.1] heptan-2-yl) ethane were sequentially added and stirred at 80 ° C. for 5 hours under a nitrogen atmosphere. . Thereafter, the reaction solution was distilled under reduced pressure to remove dimethyl sulfoxide, and then 300 g of ion exchange water, 350 mg of sodium tungstate dihydrate and 5.0 g of disodium hydrogen phosphate were added to maintain the pH of the reaction solution. Then, 5.6 ml of 30% hydrogen peroxide solution was carefully added dropwise at room temperature and stirred at 60 ° C. for 1 hour. Thereafter, the mixture was concentrated under reduced pressure to remove water, and the residue was extracted twice with methanol, and then concentrated under reduced pressure to remove methanol, whereby 1,1-difluoro-2- (bicyclo [2.2.1] heptane- 27.3 g of sodium 2-yl) ethane sulfonate (hereinafter abbreviated as “compound (a)”) was obtained.
Next, a solution obtained by dissolving 7.0 g of triphenylsulfonium bromide in 75 ml of ion-exchanged water was placed in a 200 ml eggplant flask, and 5.0 g of compound (a) and 75 ml of methylene chloride were added at room temperature. Stir for 1 hour. Thereafter, the organic layer was separated, washed 5 times with ion-exchanged water, and concentrated under reduced pressure to obtain white solid triphenylsulfonium 1,1-difluoro-2- (bicyclo [2.2.1] heptane- There were obtained 8.35 g of 2-yl) ethanesulfonate.
This compound is used as an acid generator (A-1), and the chemical structural formula thereof is shown below.

As a result of mass spectrometry of the acid generator (A-1), the anion portion was m / z = 239 (M +).
Moreover, the result (chemical shift δ (ppm)) of the ¹ H-NMR analysis of the acid generator (A-1) is as follows.
7.80-7.65 (15H)
2.45 to 2.06 (4H)
1.94 to 1.77 (1H)
1.58 to 0.74 (8H)

Synthesis Example 2: Synthesis of acid generator (A-2) A solution prepared by dissolving 6.45 g of diphenyliodonium chloride in 100 ml of ion-exchanged water was placed in a 300 ml eggplant flask, and 5.0 g of compound (a) and 100 of methylene chloride were obtained. Milliliter was added at room temperature and stirred at the same temperature for 1 hour. Thereafter, the organic layer was separated, washed 5 times with ion-exchanged water, concentrated under reduced pressure, and diphenyliodonium 1,1-difluoro-2- (bicyclo [2.2.1] heptane-2-ylate in the form of a white solid. Y) 8.1 g of ethanesulfonate was obtained.
This compound is used as an acid generator (A-2), and the chemical structural formula thereof is shown below.

As a result of mass spectrometry of the acid generator (A-2), the anion portion was m / z = 239 (M +).
Moreover, the result (chemical shift δ (ppm)) of the ¹ H-NMR analysis of the acid generator (A-2) is as follows.
8.03 (4H)
7.56 (2H)
7.41 (4H)
2.15 to 1.72 (5H)
1.49-0.61 (8H)

Synthesis Example 3: Synthesis of acid-dissociable group-containing resin (B-1) 100 g of p-acetoxystyrene, 40.6 g of 2-methyl-2-adamantyl acrylate, 6.5 g of azobisisobutyronitrile, t-dodecyl mercaptan 1.7 g and 141 g of propylene glycol monomethyl ether were put into a separable flask and stirred at room temperature to obtain a uniform solution. Under a nitrogen atmosphere, the reaction temperature was raised to 80 ° C., and polymerization was carried out for 10 hours with stirring. After completion of the polymerization, the reaction solution was purified by reprecipitation with a large amount of methanol, and 130 g of the resulting polymer was dissolved in 800 g of propylene glycol monomethyl ether, and this was concentrated under reduced pressure.
Next, about 300 g of the polymer solution, 60 g of triethylamine, 10 g of ion-exchanged water, and 300 g of methanol were charged into a separable flask and subjected to a hydrolysis reaction with stirring and reflux. Thereafter, the hydrolyzed solution was concentrated under reduced pressure, purified by reprecipitation with a large amount of ion-exchanged water, and vacuum-dried at 50 ° C. to obtain P-hydroxystyrene / 2-methyl-2-adamantyl acrylate (in molar ratio). 77/23) 102 g of a copolymer (Mw; 9500, Mw / Mn; 1.52) was obtained. Mw and Mw / Mn are the same as those of Tosoh Corporation's high-speed GPC device (model “HLC-8120”), Tosoh Corporation GPC column (trade name “G2000HXL”; 2, “G3000HXL”; G4000HXL "; 1), and measurement was performed by gel permeation chromatography (GPC) using monodisperse polystyrene as a standard under analysis conditions of a flow rate of 1.0 ml / min, an elution solvent tetrahydrofuran, and a column temperature of 40 ° C.
This compound is referred to as acid dissociable group-containing resin (B-1), and the chemical structural formula thereof is shown below.

Synthesis Example 4: Synthesis of acid-dissociable group-containing resin (B-2) 100 g of p-acetoxystyrene, 43 g of 2-ethyl-2-adamantyl acrylate, 6.5 g of azobisisobutyronitrile, t-dodecyl mercaptan 8 g and 141 g of propylene glycol monomethyl ether were put into a separable flask and stirred at room temperature to obtain a uniform solution. Under a nitrogen atmosphere, the reaction temperature was raised to 80 ° C., and polymerization was carried out for 10 hours with stirring. After completion of the polymerization, the reaction solution was purified by reprecipitation with a large amount of methanol, and 132 g of the resulting polymer was dissolved in 800 g of propylene glycol monomethyl ether, and concentrated under reduced pressure.
Next, about 300 g of the polymer solution, 60 g of triethylamine, 10 g of ion-exchanged water, and 300 g of methanol were charged into a separable flask, and a hydrolysis reaction was performed under stirring and reflux. Thereafter, the hydrolyzed solution was concentrated under reduced pressure, purified by reprecipitation with a large amount of ion-exchanged water, and vacuum-dried at 50 ° C. to obtain P-hydroxystyrene / 2-ethyl-2-adamantyl acrylate (in molar ratio). 77/23) 104 g of copolymer (Mw; 9600, Mw / Mn; 1.49) was obtained.
This compound is referred to as acid dissociable group-containing resin (B-2), and the chemical structural formula thereof is shown below.

Synthesis Example 5: Synthesis of acid-dissociable group-containing resin (B-3) 100 g of p-acetoxystyrene, 52 g of 1-methyl-1-cyclopentyl acrylate, 6.3 g of azobisisobutyronitrile, t-dodecyl mercaptan 1 g and 150 g of propylene glycol monomethyl ether were put into a separable flask and stirred at room temperature to obtain a uniform solution. Under a nitrogen atmosphere, the reaction temperature was raised to 80 ° C., and polymerization was carried out for 10 hours with stirring. After completion of the polymerization, the reaction solution was purified by reprecipitation with a large amount of methanol, and 138 g of the resulting polymer was dissolved in 800 g of propylene glycol monomethyl ether and concentrated under reduced pressure.
Next, about 300 g of the polymer solution, 60 g of triethylamine, 10 g of ion-exchanged water, and 300 g of methanol were charged into a separable flask, and a hydrolysis reaction was performed under stirring and reflux. Thereafter, the hydrolyzed solution is concentrated under reduced pressure, purified by reprecipitation with a large amount of ion-exchanged water, and vacuum-dried at 50 ° C. to thereby obtain P-hydroxystyrene / 1-methyl-1-cyclopentyl acrylate (in molar ratio). 65/35) 110 g of a copolymer (Mw; 10500, Mw / Mn; 1.54) was obtained.
This compound is an acid dissociable group-containing resin (B-3), and the chemical structural formula is shown below.

Synthesis Example 6: Synthesis of acid-dissociable group-containing resin (B-4) 100 g of p-acetoxystyrene, 4.6 g of styrene, 38.8 g of Pt-butoxystyrene, 7.2 g of azobisisobutyronitrile, t- 2.0 g of dodecyl mercaptan and 145 g of propylene glycol monomethyl ether were put into a separable flask and stirred at room temperature to obtain a uniform solution. Under a nitrogen atmosphere, the reaction temperature was raised to 80 ° C., and polymerization was carried out for 10 hours with stirring. After completion of the polymerization, the reaction solution was purified by reprecipitation with a large amount of methanol, and 130 g of the resulting polymer was dissolved in 800 g of propylene glycol monomethyl ether, and this was concentrated under reduced pressure.
Next, about 300 g of the polymer solution, 60 g of triethylamine, 10 g of ion-exchanged water, and 300 g of methanol were charged into a separable flask, and a hydrolysis reaction was performed under stirring and reflux. Thereafter, the hydrolyzed solution was concentrated under reduced pressure, purified by reprecipitation with a large amount of ion-exchanged water, and vacuum-dried at 50 ° C. to obtain p-hydroxystyrene / pt-butoxystyrene / styrene (molar ratio of 70). / 25/5) 100 g of copolymer (Mw; 10,000, Mw / Mn; 1.55) was obtained.
This compound is defined as an acid-dissociable group-containing resin (B-4), and the chemical structural formula is shown below.

Ａ−４；Ｎ−（トリフルオロメチルスルホニルオキシ）ビシクロ［２，２，１］ヘプト−５−エン−２，３−ジカルボキシイミド

（Ｂ）酸解離性含有樹脂
Ｂ−１；ｐ−ヒドロキシスチレン／スチレン／ｐ−t−ブトキシスチレン（モル比で７０／５／２５）−ヒドロキシスチレン／アクリル酸２−メチル−２−アダマンチル（モル比で７７／２３）共重合体（Ｍw；９５００、Ｍw／Ｍn；１．５２）（合成例３）
Ｂ−２；ｐ−ヒドロキシスチレン／スチレン／ｐ−t−ブトキシスチレン（モル比で７０／５／２５）−ヒドロキシスチレン／アクリル酸２−エチル−２−アダマンチル（モル比で７７／２３）共重合体（Ｍw；９６００、Ｍw／Ｍn；１．４９）（合成例４）
Ｂ−３；ｐ−ヒドロキシスチレン／スチレン／ｐ−t−ブトキシスチレン（モル比で７０／５／２５）−ヒドロキシスチレン／アクリル酸１−メチル−１−シクロペンチル（モル比で６５／３５）共重合体（Ｍw；１０５００、Ｍw／Ｍn；１．５４）（合成例５）
Ｂ−４；ｐ−ヒドロキシスチレン／スチレン／ｐ−t−ブトキシスチレン（モル比で７０／５／２５）共重合体（Ｍw；１００００、Ｍw／Ｍn；１．５５）（合成例６）
（Ｃ）酸拡散制御剤
Ｃ−１；トリ−ｎ−オクチルアミン
Ｃ−２；２−フェニルベンズイミダゾール
（Ｄ）溶剤
Ｄ−１；乳酸エチル
Ｄ−２；プロピレングリコールモノメチルエーテルアセテート The materials used in each example and comparative example are shown below.
(A) Acid generator A-1; triphenylsulfonium 1,1-difluoro-2- (bicyclo [2.2.1] heptan-2-yl) ethanesulfonate (Synthesis Example 1)
A-2: Diphenyliodonium 1,1-difluoro-2- (bicyclo [2.2.1] heptan-2-yl) ethanesulfonate (Synthesis Example 2)
A-3: Triphenylsulfonium trifluoromethanesulfonate

A-4; N- (trifluoromethylsulfonyloxy) bicyclo [2,2,1] hept-5-ene-2,3-dicarboximide

(B) Acid dissociable resin B-1; p-hydroxystyrene / styrene / pt-butoxystyrene (70/5/25 in molar ratio) -hydroxystyrene / 2-methyl-2-adamantyl acrylate (mol) 77/23 by ratio) Copolymer (Mw; 9500, Mw / Mn; 1.52) (Synthesis Example 3)
B-2: p-hydroxystyrene / styrene / pt-butoxystyrene (molar ratio 70/5/25) -hydroxystyrene / acrylic acid 2-ethyl-2-adamantyl (molar ratio 77/23) Combined (Mw; 9600, Mw / Mn; 1.49) (Synthesis Example 4)
B-3; p-hydroxystyrene / styrene / pt-butoxystyrene (molar ratio 70/5/25) -hydroxystyrene / 1-methyl-1-cyclopentyl acrylate (molar ratio 65/35) Combined (Mw; 10500, Mw / Mn; 1.54) (Synthesis Example 5)
B-4: p-hydroxystyrene / styrene / pt-butoxystyrene (molar ratio 70/5/25) copolymer (Mw; 10,000, Mw / Mn; 1.55) (Synthesis Example 6)
(C) Acid diffusion controller C-1; tri-n-octylamine C-2; 2-phenylbenzimidazole (D) solvent D-1; ethyl lactate D-2; propylene glycol monomethyl ether acetate

Examples 1 to 10 and Comparative Example 1
The composition of the Hoji type radiation-sensitive resin composition is shown in Table 1 (however, in each table, parts are based on weight). Each component was mixed to make a uniform solution, and then filtered through a membrane filter having a pore size of 200 nm to remove foreign substances, thereby preparing a radiation sensitive resin solution. Thereafter, these radiation-sensitive resin solutions were spin-coated on a 6-inch silicon wafer to form a resist film having a thickness of 200 nm. Next, the resist film was irradiated with an electron beam using a simple electron beam drawing apparatus (manufactured by Hitachi, model “HL800D”, output: 50 KeV, current density: 5.0 A / cm ² ). After the irradiation, PEB was performed under the conditions shown in Table 2, and then development was performed at 23 ° C. for 60 seconds by the paddle method using an aqueous solution containing 2.38% by weight of tetramethylammonium hydroxide. Thereafter, it was washed with water for 30 seconds and dried to form a resist pattern. Evaluation of the radiation sensitive resin composition was performed according to the following (1) and (2). The results are shown in Table 2.
(1) Sensitivity (L / S pattern, isolated line pattern)
A resist film formed on a silicon wafer is irradiated with an electron beam, immediately subjected to PEB, alkali developed, washed with water, and dried to form a resist pattern. A line and space pattern having a line width of 150 nm is formed. The irradiation amount formed to a line width of 1 to 1 and the irradiation amount formed to a line width of 1 to 10 were set as the optimal irradiation amount, and the sensitivity was evaluated based on the optimal irradiation amount.
(2) Resolution (L / S pattern, isolated line pattern)
The minimum dimension (nm) of the line-and-space pattern (1L1S, 1L10S) resolved when irradiated with the optimal dose of (1) was defined as the resolution.

  The radiation sensitive resin composition of the present invention contains an acid generator having the structure of the formula (1), and not only a line and space pattern at the time of pattern formation of the radiation sensitive resin composition, but also an isolated line. Since the resolution of the pattern is excellent, it is useful for forming a fine pattern by EB, EUV, or X-ray. Therefore, the radiation sensitive resin composition of the present invention is extremely useful as a chemically amplified resist for manufacturing semiconductor devices, which is expected to be further miniaturized from now on.

Claims (2)

A radiation-sensitive resin composition having a resolution of 90 nm or less in a line-and-space pattern and 100 nm or less in an isolated line pattern during pattern formation,
The resin composition is an acid generator having a structure of the following formula (1) and an alkali-insoluble or hardly-alkali-soluble resin having an acid-dissociable group, and becomes alkali-soluble when the acid-dissociable group is dissociated. A radiation-sensitive resin composition comprising an acid-dissociable group-containing resin.

(In Formula (1),
R ¹ is —R ⁵ , —COR ⁶ , —COOR ⁶ , —CON (R ⁶ ) (R ⁷ ), —N (R ⁶ ) (R ⁷ ), —N (R ⁶ ) CO (R ⁷ ), — ^{N (R 6) COOR 7,} -N (COR 6) (COR 7), - SR 6, -SOR 6, represents -SO ₂ R ^6, or -SO ₂ (oR ^6), wherein R ¹ there are a plurality of In the case where the R ¹ is contained in the norbornane structure, they may form a ring together with the carbon atom, and when two or more R ¹ are present, R ¹ may be bonded to each other to form a ring, and R ⁵ is a substituted or unsubstituted C 1-30 linear, branched or cyclic monovalent hydrocarbon group, substituted or represents a non-substituted monovalent heterocyclic organic group aryl group or a substituted or unsubstituted atoms 4 to 30 6 to 30 carbon atoms, wherein R ⁶ And R ⁷ individually represent a hydrogen atom, a substituted or unsubstituted C 1-30 linear monovalent hydrocarbon radical of branched or cyclic, substituted or unsubstituted aryl having 6 to 30 carbon atoms A group or a substituted or unsubstituted monovalent heterocyclic organic group having 4 to 30 atoms,
R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms,
k is an integer of 0 or more, n is an integer of 0 to 5, and M ⁺ represents a monovalent onium cation. )   2. The radiation-sensitive resin composition according to claim 1, which becomes alkali-soluble by irradiation with an electron beam or radiation having a wavelength of 140 nm or less.