JP5304648B2 - Radiation sensitive compositions and compounds - Google Patents

Abstract

Disclosed is a compound represented by the following general formula (1). (In the general formula (1), R represents a hydrogen atom or the like; Y represents an alkyl group or the like; q represents 0 or 1; and n represents an integer not less than 0.)

Description

  The present invention relates to a radiation-sensitive composition and a compound, and more particularly, a fine pattern by an electron beam (hereinafter sometimes referred to as “EB”) or extreme ultraviolet rays (hereinafter sometimes referred to as “EUV”). The present invention relates to a positive-type radiation-sensitive composition suitable for formation and a compound capable of obtaining the radiation-sensitive composition.

  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 lithographic processes that can do this is strongly promoted.

  However, it has become difficult to form a fine pattern with high accuracy by a lithography process using a KrF or ArF excimer laser, for example, which has been conventionally used. Therefore, recently, in order to achieve microfabrication, a lithography process using an electron beam instead of KrF or ArF excimer laser has been proposed.

  As an electron beam resist material used in a lithography process using this electron beam, for example, (1) a methacrylic main chain-cut positive resist such as PMMA (polymethyl methacrylate) (see, for example, Patent Documents 1 and 2), ( 2) A chemically amplified positive resist (for example, non-patent document) having a polyhydroxystyrene-based resin (resin for KrF excimer) and a novolak (resin for i-line) partially protected with an acid-dissociable group and an acid generator. 1), (3) (amorphous) organic low-molecule-containing positive and negative resists having a thin film-forming ability such as calixarene and fullerene (for example, see Patent Documents 3 to 11), resists using polyhydric phenol compounds (For example, refer to Patent Documents 12 to 13). In addition, a chemically amplified resist containing 1,3,5-tris [4- (2-t-butoxycarbonyloxy) phenyl] benzene has been proposed as an organic small molecule having a thin film forming ability other than calixarene and fullerene. (For example, refer nonpatent literature 2).

JP 2000-147777 A JP 11-29612 A JP-A-11-322656 JP-A-11-72916 JP-A-9-236919 International Publication No. 2005/075398 Pamphlet JP-A-7-134413 JP 9-211182 A JP-A-10-282649 Japanese Patent Application Laid-Open No. 11-143074 Japanese Patent Laid-Open No. 11-258996 JP 2006-267996 A JP 2006-235340 A Proc. SPIE. VOL5376 757-764 (2004) J. et al. Photo Sci. and Tech. VOL12 No2 375-376 (1999)

  However, among the electron beam resist materials, the positive resist (1) has problems in etching resistance and sensitivity and is difficult to put into practical use. For example, in order to improve sensitivity, those using poly-t-butyl α-chloromethylstyrene and those having atoms (N, O, S) that are easily cleaved by an electron beam at the resin end have been proposed. (Patent Documents 1 and 2), a certain improvement in sensitivity is recognized, but neither sensitivity nor etching resistance has reached a practical level. Further, the chemical amplification type positive resist (2) (for example, Non-Patent Document 1) has high sensitivity, but uses a resin, so that nano edge roughness becomes a problem when a fine pattern is formed. Here, nano edge roughness means that when the pattern is viewed from directly above, the resist pattern and the edge of the substrate interface vary irregularly in the direction perpendicular to the line direction due to the resist characteristics. It means that the edge looks uneven. Since the unevenness is transferred by the etching process using the resist as a mask, the electrical characteristics are deteriorated and the yield is reduced. In particular, improvement of nano edge roughness in an ultrafine region of 0.15 μm or less is an extremely important issue. Among the resists of (3), resists using calixarene (for example, Patent Documents 3 to 5) are excellent in etching resistance but structurally have very strong intermolecular interaction and solubility in a developer. However, a satisfactory pattern cannot be obtained. In addition, there are reports on compounds using calixarene derivatives (see, for example, Patent Document 6), but performance regarding nanoedge roughness is not clear.

  Moreover, although the resist (for example, patent documents 7-11) using fullerene is favorable about etching tolerance, the applicability | paintability and sensitivity have not reached the practical use level. In addition, a chemically amplified resist containing 1,3,5-tris [4- (2-t-butoxycarbonyloxy) phenyl] benzene as an organic small molecule having a thin film forming ability other than calixarene and fullerene (for example, Non-patent document 2) is not sufficient in applicability, adhesion to a substrate, and sensitivity, and has not reached a practical level. Furthermore, resists using polyhydric phenol compounds (for example, Patent Documents 12 to 13) have good resolution, but have not reached a practical level.

  The present invention has been made in view of such problems of the prior art, and the problem is that it effectively responds to electron beams or extreme ultraviolet rays, and is excellent in nano edge roughness, etching resistance, and sensitivity. Provided are a radiation-sensitive composition capable of forming a chemically amplified positive resist film capable of forming a fine pattern with high accuracy and stability, and a compound capable of obtaining this radiation-sensitive composition To do.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors can achieve the above-described problems with a compound having a predetermined structure and a radiation-sensitive composition containing this compound and a radiation-sensitive acid generator. The inventors have found that this is possible and have completed the present invention.

  That is, according to the present invention, the following compounds and radiation-sensitive compositions are provided.

[1] A radiation-sensitive composition comprising (a) a compound represented by the following general formula ( 2 ) and (b) a radiation-sensitive acid generator that generates an acid when irradiated with radiation.

（一般式（３−１）において、Ｒ ^１ は、非置換の炭素数１〜４０の、直鎖状、分岐状または環状のアルキル基であり、ｍは０〜３の整数である。） (In the general formula (2), each R is independently a hydrogen atom or a group represented by the following general formula (3-1) . However, at least one of R is represented by the following general formula (3-1) ( N is an integer of 0 to 30. )

(In General Formula (3-1), R ¹ is an unsubstituted, linear, branched or cyclic alkyl group having 1 to 40 carbon atoms, and m is an integer of 0 to 3.)

[ 2 ] R ¹ in the general formula (3-1) is tert-butyl, 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, 1-ethylcyclopentyl group, or 1-methylcyclopentyl. The radiation-sensitive composition according to [ 1 ], which is a group and m is 0 or 1 .

[ 3 ] The radiation-sensitive composition according to [ 2 ], wherein the (b) radiation-sensitive acid generator is at least one selected from the group consisting of an onium salt, a diazomethane compound, and a sulfonimide compound.

[ 4 ] The radiation-sensitive composition according to any one of [1] to [ 3 ], further comprising (c) an acid diffusion controller.

[ 5 ] A compound represented by the following general formula ( 2 ).

（一般式（３−１）において、Ｒ ^１ は、非置換の炭素数１〜４０の、直鎖状、分岐状または環状のアルキル基であり、ｍは０〜３の整数である。） (In the general formula (2), each R is independently a hydrogen atom or a group represented by the following general formula (3-1) . However, at least one of R is represented by the following general formula (3-1) ( N is an integer of 0 to 30. )

(In General Formula (3-1), R ¹ is an unsubstituted, linear, branched or cyclic alkyl group having 1 to 40 carbon atoms, and m is an integer of 0 to 3.)

  The radiation-sensitive composition of the present invention is a chemically amplified positive type that is sensitive to electron beams or extreme ultraviolet rays, has excellent nano edge roughness, etching resistance and sensitivity, and can form fine patterns with high accuracy and stability. This produces an effect that a resist film can be formed.

  The compound of the present invention produces a chemically amplified positive resist film that is sensitive to electron beams or extreme ultraviolet rays, has excellent nano edge roughness, etching resistance and sensitivity, and can form fine patterns with high precision and stability. The effect is that a radiation-sensitive composition that can be formed into a film can be obtained.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described below, but the present invention is not limited to the following embodiment, and is based on the ordinary knowledge of those skilled in the art without departing from the gist of the present invention. It should be understood that modifications and improvements as appropriate to the following embodiments also fall within the scope of the present invention.

[1] Compound:
The compound of the present invention is represented by the following general formula (1) (hereinafter sometimes referred to as “(a) compound”). This compound (a) is an acid-dissociable group-containing (modified) compound having a structure in which a plurality of hydroxyl groups bonded to a benzene ring have a structure in which at least one of the hydroxyl groups is protected by an acid-dissociable group. is there. Accordingly, the compound (a) is alkali-soluble after the acid dissociable group is dissociated by the acid and the acid dissociable group is eliminated.

  In the general formula (1), each R is independently a hydrogen atom or a monovalent acid dissociable group. However, at least one of R is a monovalent acid dissociable group. Y is independently substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, substituted or unsubstituted alkynyl group having 2 to 10 carbon atoms, carbon number A substituted or unsubstituted aralkyl group having 7 to 10 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 10 carbon atoms, or a substituted or unsubstituted phenoxy group. q is 0 or 1 independently of each other. n is an integer of 0 or more, preferably 0-30.

  Among these, the structure represented by the following general formula (2) is preferable.

  In the general formula (2), each R is independently a hydrogen atom or a monovalent acid dissociable group. However, at least one of R is a monovalent acid dissociable group. n is an integer of 0 or more.

  The compound (a) can be obtained, for example, by obtaining a precursor produced by the following method and then introducing at least one acid-dissociable group into the precursor.

  First, the precursor for producing the compound (a) is, for example, a reaction between a compound represented by the following general formula (4) and a compound represented by the following formula (5) in a solvent in the presence of a catalyst. It can be obtained by dehydrating and condensing at a reaction temperature of 60 ° C. to 90 ° C. for 12 hours to 50 hours. As said catalyst, an acid catalyst etc. can be mentioned, for example. For example, hydrochloric acid or the like can be used as the catalyst. The amount of the catalyst used is, for example, 2.0 ml of 12 N concentrated hydrochloric acid in a reaction system of 20 mmol of resorcinol and 6 mmol of 1,4-butane dial.

  In addition, the compound represented by the said Formula (5) can be obtained by mixing the compound represented by the following formula (5-1), water, and an acid catalyst, for example. Therefore, the compound (a) is a compound represented by the general formula (4) and a compound represented by the following formula (5-1) in the presence of water and an acid catalyst at 60 to 90 ° C. It can also be obtained by dehydration condensation for 48 hours.

  The compound represented by the above general formula (4) (hereinafter sometimes referred to as “compound (4)”) and the compound represented by the above formula (5) (hereinafter referred to as “compound (5)”) The mixing ratio is not particularly limited, but from the viewpoint of yield, the compound (4) is preferably in the range of 20.00 to 1.00 mol with respect to 1 mol of the compound (5). The range of 15.00 to 1.50 mol is more preferable, and the range of 13.0 to 2.00 mol is particularly preferable. There exists a possibility that the yield of the target compound may fall that a compound (4) is less than 1.00 mol. On the other hand, if it exceeds 20.00 mol, the yield of the target compound may be reduced.

  Further, the substrate concentration in the reaction solution (the total concentration of the compound (4) and the compound (5)) is not particularly limited, but is preferably 0.01 mol / L or more from the viewpoint of yield. It is particularly preferably 2 mol / L or more. There exists a possibility that the yield of the target compound may fall that a monomer concentration is less than 0.01 mol / L. As the solvent, for example, ethanol, isopropanol, n-propanol, and the like can be used. Among these, ethanol is preferable because a high yield can be obtained.

  The amount of the solvent used is, for example, 2.0 ml in a reaction system with 20 mmol of resorcinol and 6 mmol of 1,4-butane dial.

  Next, the compound (a) is obtained by mixing the compound having the precursor and a group represented by the general formula (3-1) or the general formula (3-2) described below with an acid or a base in a solvent. It can be obtained by reacting in the presence of a reaction time of 1 hour to 20 hours and a reaction temperature of -20 ° C to 100 ° C.

  The mixing ratio between the precursor and the compound having a group represented by the general formula (3-1) or the general formula (3-2) is not particularly limited, but from the viewpoint of yield, the precursor is used. It is preferable that the compound which has group represented by the said General formula (3-1) or General formula (3-2) with respect to 1 mol of phenolic hydroxyl groups of 0.01 mol or more is 0.05-0. More preferably, it is 80 mol. There exists a possibility that the yield of the target compound may fall that the compound which has group represented by the said general formula (3-1) or general formula (3-2) is less than 0.01 mol. On the other hand, if all the hydroxyl groups of the precursor are protected, the nano edge roughness may be deteriorated.

  R in the general formula (2) is each independently a hydrogen atom or a monovalent acid dissociable group. However, at least one of R is preferably a monovalent acid dissociable group. Although the structure of the acid dissociable group is not particularly limited, for example, a group represented by the following general formula (3-1) or (3-2) is preferable. In addition, when R in the general formula (2) is substituted with a plurality of acid dissociable groups, each R is independently a group represented by the following general formula (3-1) or (3-2) It can be.

In General Formula (3-1), R ¹ is an alkyl group having a linear, branched, or cyclic structure having 1 to 40 carbon atoms that is substituted or unsubstituted with a substituent that may include a hetero atom. And m is an integer of 0-3. In General Formula (3-2), R ² has a linear, branched, or cyclic structure having 1 to 40 carbon atoms that is substituted or unsubstituted with a substituent that may include a hetero atom. An alkyl group, and R ³ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

  Examples of the group represented by the general formula (3-1) include groups represented by the following general formulas (6-1) to (6-9).

(In the above general formulas (6-1) to (6-9), R ⁴ is an alkyl group having 1 to 5 carbon atoms, and m is an integer of 1 to 3)

  Of the groups represented by the general formulas (6-1) to (6-9), groups represented by the general formula (6-1), (6-8), or (6-9) are preferable. .

R ⁴ in the general formulas (6-1) to (6-9) is a lower alkyl group (an alkyl group having 1 to 5 carbon atoms), specifically, a methyl group, an ethyl group, a propyl group, Examples include lower linear or branched alkyl groups such as isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, and neopentyl group. Of these, a methyl group or an ethyl group is preferable, and a methyl group is more preferable.

In addition, R ¹ in the general formula (3-1) is specifically 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, 1-ethylcyclopentyl group, or 1-methylcyclopentyl. And a tert-butyl group.

  Specific examples of the group represented by the general formula (3-1) include 2-methyl-2-adamantyloxycarbonylmethyl group, 2-ethyl-2-adamantyloxycarbonylmethyl group, and 1-ethyl. A cyclopentyloxycarbonylmethyl group, a 1-methylcyclopentyloxycarbonylmethyl group, a tert-butoxycarbonylmethyl group, and a tert-butoxycarbonyl group are preferable.

  Examples of the group represented by the general formula (3-2) include groups represented by the following general formulas (7-1) to (7-14).

In the above general formulas (7-1) to (7-14), R ³ and R ⁵ are a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Examples of the alkyl group having 1 to 5 carbon atoms include lower groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl. A linear or branched alkyl group can be mentioned. Moreover, in the said General Formula (7-1)-(7-10), L is an integer of 0-2, and it is preferable that it is 0 or 1.

  Specifically, the group represented by the general formula (3-2) is represented by a 2-adamantyloxymethyl group, the following general formula (8), the following general formula (9), or the following general formula (10). Are preferred.

[2] Radiation sensitive composition:
The radiation-sensitive composition of the present invention contains the above-described compound (a) and (b) a radiation-sensitive acid generator that generates an acid when irradiated with radiation. The radiation-sensitive composition of the present invention is excellent in etching resistance because it contains a compound having a benzene ring skeleton by containing the compound (a). In addition, since the compound (a) contained in the radiation-sensitive composition of the present invention is not a resin but a low-molecular compound, aggregation due to the resin does not occur, and the nano edge roughness is excellent. Furthermore, the radiation-sensitive composition of the present invention is excellent in sensitivity because an acid-dissociable group is introduced in the same manner as a chemically amplified resist. In the lithography process, it effectively responds to an electron beam or extreme ultraviolet rays, is excellent in nano edge roughness, etching resistance, and sensitivity, and can form a fine pattern with high accuracy and stability.

[2-1] Radiation sensitive acid generator:
The (b) radiation-sensitive acid generator is a substance that generates an acid in the radiation-sensitive composition when the radiation-sensitive composition is irradiated with an electron beam or the like in a lithography process. By the action, the acid dissociable group of the compound (a) already described above can be dissociated.

  (B) The radiation sensitive acid generator is, for example, at least one selected from the group consisting of onium salts, diazomethane compounds, and sulfonimide compounds from the viewpoint of good acid generation efficiency, heat resistance, and the like. Is preferred. In addition, these can be used individually or in combination of multiple.

Examples of onium salts include iodonium salts, sulfonium salts, phosphonium salts, diazonium salts, pyridinium salts, and the like. Here, specific examples of the onium salt include triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfoniumbenzenesulfonate, triphenylsulfonium 10-camphorsulfonate, and triphenylsulfonium n-octanesulfonate. , Triphenylsulfonium 4-trifluoromethylbenzenesulfonate, triphenylsulfonium naphthalenesulfonate, triphenylsulfonium perfluorobenzenesulfonate, triphenylsulfonium 1,1,2,2-tetrafluoro-2- (tetracyclo [4.4.0 .1 ^2,5 .1 ^7,10] dodecane-8-yl) ethanesulfonate, triphenylsulfonium 1,1-difluoro - - (bicyclo [2.2.1] heptan-2-yl) ethanesulfonate;

  (4-t-butoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, (4-t-butoxyphenyl) diphenylsulfonium nonafluoro-n-butanesulfonate, (4-t-butoxyphenyl) diphenylsulfonium perfluoro-n-octanesulfonate,

  (4-hydroxyphenyl) diphenylsulfonium trifluoromethanesulfonate, (4-hydroxyphenyl) diphenylsulfonium nonafluoro-n-butanesulfonate, (4-hydroxyphenyl) diphenylsulfonium perfluoro-n-octanesulfonate, (4-hydroxyphenyl) Diphenylsulfonium 10-camphorsulfonate, (4-hydroxyphenyl) diphenylsulfonium n-octanesulfonate,

  Tris (4-methoxyphenyl) sulfonium trifluoromethanesulfonate, tris (4-methoxyphenyl) sulfonium nonafluoro-n-butanesulfonate, tris (4-methoxyphenyl) sulfonium perfluoro-n-octanesulfonate, tris (4-methoxyphenyl) ) Sulfonium 10-camphorsulfonate,

  (4-fluorophenyl) diphenylsulfonium trifluoromethanesulfonate, (4-fluorophenyl) diphenylsulfonium nonafluoro-n-butanesulfonate, (4-fluorophenyl) diphenylsulfonium 10-camphorsulfonate;

  Tris (4-fluorophenyl) sulfonium trifluoromethanesulfonate, tris (4-fluorophenyl) sulfonium nonafluoro-n-butanesulfonate, tris (4-fluorophenyl) sulfonium 10-camphorsulfonate, tris (4-fluorophenyl) sulfonium p -Toluenesulfonate, tris (4-trifluoromethylphenyl) sulfonium trifluoromethanesulfonate;

  2,4,6-trimethylphenyldiphenylsulfonium trifluoromethanesulfonate, 2,4,6-trimethylphenyldiphenylsulfonium 2,4-difluorobenzenesulfonate, 2,4,6-trimethylphenyldiphenylsulfonium 4-trifluoromethylbenzenesulfonate;

  Diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, diphenyliodonium 10-camphorsulfonate, diphenyliodonium n-octanesulfonate,

  Bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) iodonium perfluoro-n-octanesulfonate, Bis (4-t-butylphenyl) iodonium 10-camphorsulfonate, bis (4-t-butylphenyl) iodonium n-octanesulfonate,

  (4-methoxyphenyl) phenyliodonium trifluoromethanesulfonate, (4-methoxyphenyl) phenyliodonium nonafluoro-n-butanesulfonate, (4-methoxyphenyl) phenyliodonium perfluoro-n-octanesulfonate,

  (4-fluorophenyl) phenyliodonium trifluoromethanesulfonate, (4-fluorophenyl) phenyliodonium nonafluoro-n-butanesulfonate, (4-fluorophenyl) phenyliodonium 10-camphorsulfonate;

  Bis (4-fluorophenyl) iodonium trifluoromethanesulfonate, bis (4-fluorophenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-fluorophenyl) iodonium 10-camphorsulfonate;

  Bis (4-chlorophenyl) iodonium trifluoromethanesulfonate, bis (4-chlorophenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-chlorophenyl) iodonium perfluoro-n-octanesulfonate, bis (4-chlorophenyl) iodonium 10- Camphorsulfonate, bis (4-chlorophenyl) iodonium n-octanesulfonate, bis (4-chlorophenyl) iodonium 4-trifluoromethylbenzenesulfonate, bis (4-chlorophenyl) iodonium perfluorobenzenesulfonate;

  Bis (4-trifluoromethylphenyl) iodonium trifluoromethanesulfonate, bis (4-trifluoromethylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-trifluoromethylphenyl) iodonium perfluoro-n-octanesulfonate, Bis (4-trifluoromethylphenyl) iodonium n-dodecylbenzenesulfonate, bis (4-trifluoromethylphenyl) iodonium p-toluenesulfonate, bis (4-trifluoromethylphenyl) iodoniumbenzenesulfonate, bis (4-trifluoro Methylphenyl) iodonium 10-camphorsulfonate, bis (4-trifluoromethylphenyl) iodonium n-octanesulfonate, bis (4-trifluoro) B methylphenyl) iodonium 4-trifluoromethyl benzenesulfonate, bis (4-trifluoromethylphenyl) iodonium perfluoro sulfonate;

  Among these, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium 10-camphorsulfonate, (4-hydroxyphenyl) diphenylsulfonium trifluoromethanesulfonate, (4-hydroxyphenyl) diphenyl Sulfonium nonafluoro-n-butanesulfonate, tris (4-methoxyphenyl) sulfonium trifluoromethanesulfonate, tris (4-methoxyphenyl) sulfonium nonafluoro-n-butanesulfonate, (4-fluorophenyl) diphenylsulfonium trifluoromethanesulfonate, 4-Fluorophenyl) diphenylsulfonium nonafluoro-n-butanesulfonate 2,4,6-trimethylphenyldiphenylsulfonium trifluoromethanesulfonate, 2,4,6-trimethylphenyldiphenylsulfonium 2,4-difluorobenzenesulfonate, 2,4,6-trimethylphenyldiphenylsulfonium 4-trifluoromethylbenzenesulfonate Diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium 10-camphorsulfonate, bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro -N-butanesulfonate, bis (4-t-butylphenyl) iodonium 10-camphorsulfonate (4-fluorophenyl) phenyliodonium trifluoromethanesulfonate, (4-fluorophenyl) phenyliodonium nonafluoro-n-butanesulfonate, (4-fluorophenyl) phenyliodonium 10-camphorsulfonate, bis (4-fluorophenyl) iodonium trifluoro Lomethanesulfonate, bis (4-fluorophenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-fluorophenyl) iodonium 10-camphorsulfonate, and tris (4-trifluoromethylphenyl) sulfonium trifluoromethanesulfonate are preferred. These can be used alone or in combination.

  Examples of the diazomethane compound include bis (trifluoromethanesulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (3,3-dimethyl-1,5-dioxaspiro [5.5] dodecane-8-sulfonyl) diazomethane, bis ( 1,4-dioxaspiro [4.5] decane-7-sulfonyl) diazomethane, bis (t-butylsulfonyl) diazomethane, and the like can be given.

  Among these, bis (cyclohexylsulfonyl) diazomethane, bis (3,3-dimethyl-1,5-dioxaspiro [5.5] dodecane-8-sulfonyl) diazomethane, bis (1,4-dioxaspiro [4.5] Decane-7-sulfonyl) diazomethane is preferred. These can be used alone or in combination.

  Examples of the sulfonimide compound include 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- (10-camphorsulfonyloxy) succinimide, N- (10-camphorsulfonyloxy) phthalimide, 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) naphthyl Imido, N-[(5-methyl-5-carboxymethylbicyclo [2.2.1] heptan-2-yl) sulfonyloxy] succinimide;

  N- (n-octylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (n-octylsulfonyloxy) bicyclo [2.2.1] heptane- 5,6-oxy-2,3-dicarboximide,

  N- (perfluorophenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (perfluorophenylsulfonyloxy) -7-oxabicyclo [2.2. 1] hept-5-ene-2,3-dicarboximide, N- (perfluorophenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboximide,

  N- (nonafluoro-n-butylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (nonafluoro-n-butylsulfonyloxy) -7-oxabicyclo [ 2.2.1] Hept-5-ene-2,3-dicarboximide, N- (nonafluoro-n-butylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3 -Dicarboximide,

  N- (perfluoro-n-octylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (perfluoro-n-octylsulfonyloxy) -7-oxa Bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (perfluoro-n-octylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy- 2,3-dicarboximide,

  Among these, N- (trifluoromethylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (10-camphorsulfonyloxy) succinimide, N- [ (5-Methyl-5-carboxymethylbicyclo [2.2.1] heptan-2-yl) sulfonyloxy] succinimide is preferred. These can be used alone or in combination.

  The amount of the (b) radiation sensitive acid generator used is preferably 0.1 to 30 parts by mass, and more preferably 0.5 to 25 parts by mass with respect to 100 parts by mass of the compound (a). preferable. (B) There exists a possibility that a sensitivity and developability may fall that the usage-amount of a radiation sensitive acid generator is less than 0.1 mass part. On the other hand, if it exceeds 30 parts by mass, transparency to radiation, pattern shape, heat resistance and the like may be reduced.

[2-2] (c) Acid diffusion controller:
The radiation-sensitive composition of the present invention preferably further contains (c) an acid diffusion controller. (C) The acid diffusion control agent is a component having an action of controlling the diffusion phenomenon in the resist film of the acid generated from the (b) radiation sensitive acid generator by exposure and suppressing undesirable chemical reaction in the non-exposed region. is there. By blending such an acid diffusion control agent (c), the storage stability of the resulting radiation-sensitive composition is improved, the resolution as a resist is further improved, and the heat treatment from exposure to exposure is performed. The change of the line width of the resist pattern due to the fluctuation of the holding time (PED) until the time can be suppressed, and a radiation-sensitive composition having extremely excellent process stability can be obtained.

  (C) As an acid diffusion controlling agent, for example, a nitrogen-containing organic compound or a photosensitive basic compound is preferable. Examples of the nitrogen-containing organic compound include a compound represented by the following general formula (11) (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 Examples include heterocyclic compounds.

(In the general formula (11), each R ⁶ is independently a hydrogen atom, an optionally substituted linear, branched or cyclic alkyl group, an optionally substituted aryl group, or a substituted group. It is an aralkyl group that may be

  Examples of the nitrogen-containing compound (i) include mono (cyclo) alkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, cyclohexylamine; di-n- Butylamine, di-n-pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decylamine, cyclohexylmethylamine, dicyclohexylamine, etc. Di (cyclo) alkylamines; triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine , Tri-n-nonylamine, tri-n-decylamine, cyclohexyl Tri (cyclo) alkylamines such as dimethylamine, methyldicyclohexylamine, tricyclohexylamine; substituted alkylamines such as triethanolamine; aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3- Methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenylamine, naphthylamine, 2,4,6-tri-tert-butyl-N-methylaniline, N-phenyldiethanolamine, 2,6-diisopropylaniline, etc. Aromatic amines are preferred.

  Examples of the nitrogen-containing compound (ii) include ethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diaminodiphenylmethane, and 4,4′-diaminodiphenylether. 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-methyl ester Benzene], bis (2-dimethylaminoethyl) ether, bis (2-diethylaminoethyl) ether, 1- (2-hydroxyethyl) -2-imidazolidinone, 2-quinoxalinol, N, N, N ′ , N′-tetrakis (2-hydroxypropyl) ethylenediamine, N, N, N ′, N ″, N ″ -pentamethyldiethylenetriamine and the like are preferable.

  As the nitrogen-containing compound (iii), for example, polyethyleneimine, polyallylamine, 2-dimethylaminoethylacrylamide polymer and the like are preferable.

  Examples of the amide group-containing compound include Nt-butoxycarbonyldi-n-octylamine, Nt-butoxycarbonyldi-n-nonylamine, Nt-butoxycarbonyldi-n-decylamine, and Nt. -Butoxycarbonyldicyclohexylamine, Nt-butoxycarbonyl-1-adamantylamine, Nt-butoxycarbonyl-2-adamantylamine, Nt-butoxycarbonyl-N-methyl-1-adamantylamine, (S)- (-)-1- (t-butoxycarbonyl) -2-pyrrolidinemethanol, (R)-(+)-1- (t-butoxycarbonyl) -2-pyrrolidinemethanol, Nt-butoxycarbonyl-4-hydroxy Piperidine, Nt-butoxycarbonylpyrrolidine, Nt-butoxycarbo Rupiperazine, N, N-di-t-butoxycarbonyl-1-adamantylamine, N, N-di-t-butoxycarbonyl-N-methyl-1-adamantylamine, Nt-butoxycarbonyl-4,4′- Diaminodiphenylmethane, N, N′-di-t-butoxycarbonylhexamethylenediamine, N, N, N′N′-tetra-t-butoxycarbonylhexamethylenediamine, N, N′-di-t-butoxycarbonyl-1 , 7-diaminoheptane, N, N′-di-t-butoxycarbonyl-1,8-diaminooctane, N, N′-di-t-butoxycarbonyl-1,9-diaminononane, N, N′-di- t-butoxycarbonyl-1,10-diaminodecane, N, N′-di-t-butoxycarbonyl-1,12-diaminododecane, N N'-di-t-butoxycarbonyl-4,4'-diaminodiphenylmethane, Nt-butoxycarbonylbenzimidazole, Nt-butoxycarbonyl-2-methylbenzimidazole, Nt-butoxycarbonyl-2-phenyl In addition to Nt-butoxycarbonyl group-containing amino compounds such as benzimidazole, formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, Pyrrolidone, N-methylpyrrolidone, N-acetyl-1-adamantylamine, isocyanuric acid tris (2-hydroxyethyl) and the like are preferable.

  Examples of the urea compound include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, and tri-n-butyl. Thiourea and the like are preferable.

  Examples of the nitrogen-containing heterocyclic compound include imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, benzimidazole, 2-phenylbenzimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2. -Imidazoles such as methyl-1H-imidazole; pyridine, 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, 2-methyl-4-phenyl Pyridines such as pyridine, nicotine, nicotinic acid, nicotinamide, quinoline, 4-hydroxyquinoline, 8-oxyquinoline, acridine, 2,2 ′: 6 ′, 2 ″ -terpyridine; piperazine, 1- (2-hydroxy In addition to piperazines such as ethyl) piperazine Pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, piperidine ethanol, 3-piperidino-1,2-propanediol, 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 are preferable.

  The photosensitive basic compound is a component that efficiently decomposes into the corresponding neutral fragment in the exposed region and remains as it is without being decomposed in the unexposed portion. Such a photosensitive basic compound can improve the sensitivity because it can effectively use the acid generated in the exposed portion (exposed region) as compared with the non-photosensitive basic compound.

  The kind of the photosensitive basic compound is not particularly limited as long as it has the above-mentioned properties. For example, compounds represented by the following general formula (12-1) and general formula (12-2) are preferable. Can be used.

(In General Formula (12-1) and General Formula (12-2), R ^{7 to} R ¹¹ are each a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms that may have a substituent, or substituted represents also good alicyclic hydrocarbon group, X ^- is ^{OH -, R 12 OH -,} R 12 COO - represents, the X ^{- R 12} of a monovalent organic group)

Examples of the alkyl group having 1 to 10 carbon atoms that may have a substituent of R ^{7 to} R ¹¹ include, for example, a methyl group, an ethyl group, an n-butyl group, a tert-butyl group, a trifluoromethyl group, and a fluorine atom. Methoxy group, t-butoxy group, t-butoxycarbonylmethyloxy group and the like. R ^{7 to} R ¹¹ are preferably a hydrogen atom or a tert-butyl group.

Further, X ^- as the monovalent organic group R ^12, for example, may be mentioned an optionally substituted alkyl group, an aryl group which may have a substituent.

The above ^X - _{^{is, OH -, CH 3 COO -}} , can be suitably used a compound represented by the following formula.

Specific examples of the photosensitive basic compound include a triphenylsulfonium compound (a compound represented by the above general formula (12-1)), in which an anion portion (X ⁻ ) is OH ⁻ , CH ₃ COO ^−. Or a compound represented by the following formula can be cited as a preferred example.

  In addition, the said (c) acid diffusion controlling agent can be used individually or in mixture of 2 or more types.

  (C) The compounding amount of the acid diffusion controller is preferably 15 parts by mass or less, more preferably 0.001 to 10 parts by mass with respect to 100 parts by mass of the compound (a), and 0.005. It is especially preferable that it is -5 mass parts. (C) If the blending amount of the acid diffusion controller is more than 15 parts by mass, the sensitivity as a resist and the developability of the exposed part may be lowered. Note that if the amount of the (c) acid diffusion controller is less than 0.001 parts by mass, the pattern shape and dimensional fidelity as a resist may be lowered depending on the process conditions.

[2-3] Other components:
The radiation sensitive composition of the present invention is preferably prepared by dissolving the compound (a), (b) a radiation sensitive acid generator, and (c) an acid diffusion controller in a solvent. That is, it is preferable to contain a solvent as another component. Moreover, various additives, such as surfactant, a sensitizer, and an aliphatic additive, can be mix | blended with the radiation sensitive composition of this invention as other components as needed.

  The solvent is preferably at least one selected from the group of propylene glycol monomethyl ether acetate, 2-heptanone and cyclohexanone (hereinafter referred to as “solvent 1”). As the solvent, a solvent other than the above-described solvent 1 (hereinafter referred to as “other solvent”) can also be used. In addition, the solvent 1 and another solvent can also be mixed and used.

  Examples of other solvents include propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol mono-i-propyl ether acetate, propylene glycol mono-n-butyl ether acetate, propylene glycol mono-i- Propylene glycol monoalkyl ether acetates such as butyl ether acetate, propylene glycol mono-sec-butyl ether acetate, propylene glycol mono-t-butyl ether acetate;

  2-butanone, 2-pentanone, 3-methyl-2-butanone, 2-hexanone, 4-methyl-2-pentanone, 3-methyl-2-pentanone, 3,3-dimethyl-2-butanone, 2-octanone, etc. Linear or branched ketones; cyclic ketones such as cyclopentanone, 3-methylcyclopentanone, 2-methylcyclohexanone, 2,6-dimethylcyclohexanone, isophorone; methyl 2-hydroxypropionate, 2 -Ethyl hydroxypropionate, n-propyl 2-hydroxypropionate, i-propyl 2-hydroxypropionate, n-butyl 2-hydroxypropionate, i-butyl 2-hydroxypropionate, sec-butyl 2-hydroxypropionate 2-hydroxypropionate t-butyl 2-hydroxy Propionate alkyls; methyl 3-methoxy propionate, 3-methoxy ethyl propionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate and the like of 3-alkoxy propionic acid alkyl ethers other,

  n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclohexanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether , Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di-n-propyl ether, diethylene glycol di-n-butyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, propylene glycol monomethyl ether , Propylene glycol monoethyl Ether, propylene glycol mono -n- propyl ether,

  Toluene, xylene, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutyrate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3 -Methyl-3-methoxybutyl propionate, 3-methyl-3-methoxybutyl butyrate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl acetoacetate, ethyl acetoacetate, methyl pyruvate, ethyl pyruvate N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, benzyl ethyl ether, di-n-hexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, caproic acid, caprylic acid, 1-o Pentanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, .gamma.-butyrolactone, ethylene carbonate, and propylene carbonate.

  Among these other solvents, linear or branched ketones, cyclic ketones, propylene glycol monoalkyl ether acetates, alkyl 2-hydroxypropionate, alkyl 3-alkoxypropionate, γ-butyrolactone Etc. are preferred. These other solvents can be used alone or in admixture of two or more.

  When using the mixed solvent of the solvent 1 and another solvent as a solvent, it is preferable that the ratio of another solvent is 50 mass% or less with respect to all the solvents, and it is further 40 mass% or less. It is preferably 30% by mass or less.

  In general, the radiation-sensitive composition of the present invention preferably has a total solid content of 1 to 50% by mass, and more preferably 1 to 25% by mass. And (a) a compound, (b) a radiation sensitive acid generator, (c) an acid diffusion control agent, and other additives (excluding the solvent) as necessary, so that the total solid content concentration is obtained. After dissolving in a solvent to obtain a uniform solution, it is preferable to obtain a composition solution composed of a radiation-sensitive composition by, for example, filtering with a filter having a pore size of about 0.2 μm.

  In addition, the surfactant contained as other components is a component having an effect of improving coatability, striation, developability and the like. Examples of such surfactants include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octylphenyl ether, polyoxyethylene n-nonylphenyl ether, and polyethylene glycol dilaurate. In addition to nonionic surfactants such as polyethylene glycol distearate, KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, no. 95 (manufactured by Kyoeisha Chemical Co., Ltd.), F-top EF301, EF303, EF352 (manufactured by Tochem Products), Megafax F171, F173 (manufactured by Dainippon Ink & Chemicals), Florard FC430, FC431 (Sumitomo 3M) Asahi Guard AG710, Surflon S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 (Asahi Glass Co., Ltd.), etc. Can do. These surfactants can be used singly or in combination of two or more.

  Surfactant can be used individually or in mixture of 2 or more types. It is preferable that the compounding quantity of surfactant is 0.001-2 mass parts with respect to 100 mass parts of (a) compounds.

  The sensitizer absorbs radiation energy and transmits the energy to (b) the radiation-sensitive acid generator, thereby increasing the amount of acid produced. The radiation-sensitive composition It has the effect of improving the apparent sensitivity. Examples of such sensitizers include carbazoles, acetophenones, benzophenones, naphthalenes, phenols, biacetyl, eosin, rose bengal, pyrenes, anthracenes, phenothiazines, and the like. In addition, these sensitizers can be used individually or in mixture of 2 or more types. It is preferable that the compounding quantity of a sensitizer is 0.1-10 mass parts with respect to 100 mass parts of (a) compounds.

  Further, by blending a dye or pigment, the latent image in the exposed area can be visualized, and the influence of halation during exposure can be reduced. By blending an adhesion aid, the adhesion to the substrate can be improved.

  Moreover, the alicyclic additive which has an acid dissociable group, and the alicyclic additive which does not have an acid dissociable group can be added to the radiation sensitive composition of this invention. An alicyclic additive having an acid dissociable group or an alicyclic additive not having an acid dissociable group is a component having an action of further improving dry etching resistance, pattern shape, adhesion to a substrate, and the like.

Examples of such alicyclic additives include 1-adamantanecarboxylic acid, 2-adamantanone, 1-adamantanecarboxylic acid t-butyl, 1-adamantanecarboxylic acid t-butoxycarbonylmethyl, 1-adamantanecarboxylic acid α. -Butyrolactone ester, 1,3-adamantane dicarboxylic acid di-t-butyl, 1-adamantane acetate t-butyl, 1-adamantane acetate t-butoxycarbonylmethyl, 1,3-adamantane diacetate di-t-butyl, 2, Adamantane derivatives such as 5-dimethyl-2,5-di (adamantylcarbonyloxy) hexane; t-butyl deoxycholic acid, t-butoxycarbonylmethyl deoxycholic acid, 2-ethoxyethyl deoxycholic acid, 2-deoxycholic acid 2- Cyclohexyloxyethyl, deoxy Deoxycholic acid esters such as 3-oxocyclohexyl cholic acid, tetrahydropyranyl deoxycholic acid, mevalonolactone ester of deoxycholic acid; t-butyl lithocholic acid, t-butoxycarbonylmethyl lithocholic acid, 2-ethoxyethyl lithocholic acid, Lithocholic acid esters such as 2-cyclohexyloxyethyl lithocholic acid, 3-oxocyclohexyl lithocholic acid, tetrahydropyranyl lithocholic acid, mevalonolactone ester of lithocholic acid; dimethyl adipate, diethyl adipate, dipropyl adipate, din adipate - butyl, alkyl carboxylic acid esters such as adipate t- butyl or 3- [2-hydroxy-2,2-bis (trifluoromethyl) ethyl] tetracyclo [4.4.0.1 ^{2, 5} 1 ^7,10 ] dodecane and the like.

  These alicyclic additives can be used alone or in admixture of two or more. It is preferable that the compounding quantity of an alicyclic additive is 0.5-20 mass parts with respect to 100 mass parts of (a) compounds. There exists a possibility that the heat resistance as a resist may fall that the compounding quantity of an alicyclic additive exceeds 20 mass parts.

  Furthermore, examples of additives other than the above include alkali-soluble resins, low-molecular alkali solubility control agents having an acid-dissociable protecting group, antihalation agents, storage stabilizers, antifoaming agents, and the like.

[3] Method for forming resist pattern:
The radiation-sensitive composition of the present invention is particularly useful as a chemically amplified resist. In the above chemically amplified resist, (b) the acid-dissociable group of the compound is eliminated by the action of the acid generated from the radiation-sensitive acid generator by exposure, and an alkali-soluble site is generated. The solubility of the exposed portion of the resist in the alkaline developer is increased, and the exposed portion is dissolved and removed by the alkaline developer to obtain a positive resist pattern.

  When forming a resist pattern with the radiation-sensitive composition of the present invention, the above-described composition solution is coated with, for example, a silicon wafer or aluminum by an appropriate application means such as spin coating, cast coating or roll coating. A resist film is formed by coating on a substrate such as a wafer, and in some cases, a heat treatment (hereinafter referred to as “PB”) is performed in advance, and then a predetermined resist pattern is formed on the resist film. Exposure. Examples of radiation used at that time include far ultraviolet rays such as KrF excimer laser (wavelength 248 nm), EUV (extreme ultraviolet rays, wavelength 13 nm, etc.), X-rays such as synchrotron radiation, and charged particle beams such as electron beams. Can be appropriately selected and used. Further, the exposure conditions such as the exposure amount are appropriately selected according to the composition of the radiation-sensitive composition, the kind of additive, and the like, and may be immersion exposure.

  In the present invention, it is preferable to perform heat treatment (hereinafter referred to as “PEB”) after exposure. This PEB makes it possible to smoothly proceed with elimination of the acid dissociable group of the compound (a). The heating conditions for PEB vary depending on the composition of the radiation-sensitive composition, but are preferably 30 to 200 ° C, and more preferably 50 to 170 ° C.

  In the present invention, in order to maximize the potential of the radiation-sensitive composition, as disclosed in, for example, Japanese Patent Publication No. 6-12452, an organic or inorganic reflective material is used. A prevention film can also be formed. 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. Or these techniques can also be used together.

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

  The concentration of the alkaline aqueous solution is preferably 10% by mass or less. If the concentration of the alkaline aqueous solution is more than 10% by mass, the unexposed area may be dissolved in the developer. Further, the developer is preferably pH 8 to 14, and more preferably pH 9 to 14.

  Further, for example, an organic solvent can be added to the developer composed of the alkaline aqueous solution. 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; methyl alcohol, ethyl alcohol, and n-propyl. Alcohols such as alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclopentanol, cyclohexanol, 1,4-hexanediol, 1,4-hexanedimethylol; ethers such as tetrahydrofuran and dioxane Esters such as ethyl acetate, n-butyl acetate and i-amyl acetate; aromatic hydrocarbons such as toluene and xylene; phenol, acetonylacetone and dimethylformamide. These organic solvents can be used alone or in admixture of two or more.

  The amount of the organic solvent used is preferably 100 parts by volume or less with respect to 100 parts by volume of the alkaline aqueous solution. If the amount of the organic solvent used is more than 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.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. In the examples and comparative examples, “parts” and “%” are based on mass unless otherwise specified.

Example 1 Compound (A-1):
2.20 g of resorcinol and 0.79 g of 2,5-dimethoxytetrahydrofuran are added to 6 mL of ethanol, 2 ml of 12N hydrochloric acid is added, and the mixture is heated at 80 ° C. for 24 hours, and then the reaction solution is poured into methanol to obtain a solid. The solid was washed with about 200 ml of methanol and dried under vacuum at 60 ° C. for 24 hours to obtain a light yellow solid (S) having the following structure in a yield of 29%. The obtained solid Mn was 9500, and Mw / Mn was 2.1.

  From the result of MALDI-TOF-MS (model number SHIMAZU / KRATOS matrix-assisted laser ionization time-of-flight mass spectrometer KOMPACT MALDI IV tDE, manufactured by Shimadzu Corporation) of the obtained pale yellow solid (S), it was cyclic in the polymer chain. It was identified as a compound having a repeating unit of calix [4] resorcinarene which is an oligomer.

（ｎは０以上の整数を示す。）

(N represents an integer of 0 or more.)

After adding 50 g of pyridine to 1 g of the obtained pale yellow solid (S) and 0.25 g of tetrabutylammonium bromide (TBAB) and stirring, 2.0 g of di-tert-butyl dicarbonate (DiBoc) was slowly added dropwise. Stir at room temperature for 6 hours. After completion of the reaction, the mother liquor was diluted with chloroform, washed 3 times with 1N hydrochloric acid and twice with water, the organic layer was dried using a desiccant composed of anhydrous magnesium sulfate, and the desiccant was filtered off. The organic layer was concentrated and purified by reprecipitation using chloroform as a good solvent and n-hexane as a poor solvent to obtain a solid. The yield was 50%. As a result of ¹ H-NMR analysis, the protection ratio (ratio in which the hydrogen atom of the phenolic hydroxyl group in compound (1) was substituted with a t-butoxycarbonyl group) in the following compound (A-1) was 50%. there were.

Example 2 Synthesis of Compound A-2:
1 g of the obtained pale yellow solid (S) and 0.25 g of tetrabutylammonium bromide were added, 10 g of 1-methyl-2-pyrrolidone was added, and the mixture was stirred at 70 ° C. for 1 hour. Thereafter, 1.2 g of potassium carbonate was added and stirred at 70 ° C. for 1 hour. Thereafter, 1.8 g of t-butyl bromoacetate dissolved in 3 g of 1-methyl-2-pyrrolidone was gradually added and stirred at 60 ° C. for 6 hours. After cooling to room temperature, extraction with water / methylene chloride was performed, followed by washing twice with 100 ml of a 3 wt% oxalic acid aqueous solution and then twice with 100 ml. After discarding the aqueous layer, the organic layer was dried over magnesium sulfate. After filtering off the desiccant, the organic layer was concentrated and purified by reprecipitation using chloroform as a good solvent and n-hexane as a poor solvent to obtain a solid. The yield was 55%. As a result of ¹ H-NMR analysis, the following compound (A-2) had a protection rate of 50% (the ratio in which the hydrogen atom of the phenolic hydroxyl group in compound (1) was replaced with a tert-butoxycarbonylmethyl group). Met.

Example 3 Synthesis of Compound A-3:
1 g of the obtained pale yellow solid (S) and 0.25 g of tetrabutylammonium bromide were added, 10 g of 1-methyl-2-pyrrolidone was added, and the mixture was stirred at 70 ° C. for 1 hour. Thereafter, 1.2 g of potassium carbonate was added and stirred at 70 ° C. for 1 hour. Thereafter, 2.6 g of 2-methyl-2-adamantyl bromoacetate dissolved in 3 g of 1-methyl-2-pyrrolidone was gradually added and stirred at 60 ° C. for 6 hours. After cooling to room temperature, extraction with water / methylene chloride was performed, followed by washing twice with 100 ml of a 3 wt% oxalic acid aqueous solution and then twice with 100 ml. After discarding the aqueous layer, the organic layer was dried over magnesium sulfate. After filtering off the desiccant, the organic layer was concentrated and purified by reprecipitation using chloroform as a good solvent and n-hexane as a poor solvent to obtain a solid. The yield was 55%. As a result of ¹ H-NMR analysis, the protection rate in the following compound (A-2) (the hydrogen atom of the phenolic hydroxyl group in compound (1) was substituted with a 2-methyl-2-adamantyloxycarbonylmethyl group) The ratio) was 50%.

Comparative Synthesis Example 1 Acid-dissociable group-containing resin (A-4):
Polyhydroxystyrene (VP8000, Nippon Soda Co., Ltd. (Mw9000, Mw / Mn = 1.1) 10 g of butyl acetate in 20% solution was slowly added dropwise with di-t-butyl-di-carbonate 5.50 g and triethylamine 2.80 g. The reaction solution was stirred for 7 hours at 60 ° C. Thereafter, a large amount of water was added to the reaction solution, and reprecipitation purification was repeated, followed by drying under reduced pressure, whereby the hydroxy group was 30% t-butoxycarbonyl. 12.0 g of polyhydroxystyrene (A-4) protected with 1 was obtained.

Example 4
100 parts of compound (A-1), (b) 9 parts of triphenylsulfonium trifluoromethanesulfonate (shown as “B-1” in Table 1) as a radiation sensitive acid generator, and (c) trimethyl as an acid diffusion controller. -N-octylamine (shown as "C-1" in Table 1) 0.3 part, ethyl lactate (shown as "D-1" in Table 1) 600 parts as a solvent, and propylene glycol monomethyl ether acetate ( 1500 parts (shown as “D-3” in Table 1) were mixed, and this mixed solution was filtered through a membrane filter having a pore size of 200 nm to obtain a composition solution (radiation sensitive composition).

Next, in the clean track ACT-8 manufactured by Tokyo Electron Co., Ltd., the above composition solution was spin-coated on a silicon wafer, followed by PB (heat treatment) at 90 ° C. for 90 seconds to form a resist having a film thickness of 100 nm (radiation sensitive). Composition) A film was formed. 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 at 90 ° C. for 90 seconds. Thereafter, using a 2.38% tetramethylammonium hydroxide aqueous solution, development was carried out at 23 ° C. for 1 minute by the paddle method, followed by washing with pure water and drying to form a resist pattern. The resist thus formed was evaluated in the following manner.

(1) Sensitivity (L / S):
The resist film formed on the silicon wafer was exposed to light, immediately subjected to PEB, then developed with alkali, washed with water, and dried to form a resist pattern. At this time, the exposure amount for forming a line-and-space pattern (1L1S) having a line width of 150 nm in a one-to-one line width was set as the optimum exposure amount, and the sensitivity was evaluated based on the optimum exposure amount.

(2) 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.

(3) Surface roughness:
For a line-and-space pattern (1L1S) having a design dimension of 150 nm, the cross-sectional dimension of the line pattern is measured by a scanning electron microscope, the minimum dimension is Lin, the maximum dimension is Lout, and (Lout−Lin) is Ld. The following criteria were evaluated according to the value of:
Ld is less than 0.01 μm: good Ld is 0.01 μm or more: poor

In each evaluation result of this example, the sensitivity was 25.0 μC / cm ² , the resolution was 90 nm, and the film surface roughness was good.

(Examples 5 to 11, Comparative Example 1)
A composition solution (radiation-sensitive composition) was prepared in the same manner as in Example 4 except that the components shown in Table 1 were mixed in the amounts shown in Table 1 to form a uniform solution and treated under the conditions shown in Table 2. did. Thereafter, a resist pattern was formed using the prepared radiation-sensitive composition, and each of the above evaluations was performed on the formed resist. The evaluation results are shown in Table 2.

  In addition, the material used for Examples 4-11 and the comparative example 1 is shown below.

(B) Radiation sensitive acid generator:
B-1: Triphenylsulfonium trifluoromethanesulfonate B-2: N- (trifluoromethylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide

(C) Acid diffusion control agent:
C-1: Tri-n-octylamine C-2: Triphenylsulfonium salicylate C-3: Nt-butoxycarbonyldicyclohexylamine

solvent:
D-1: Ethyl lactate D-2: Propylene glycol monomethyl ether acetate

  As is clear from Table 2, the radiation sensitive compositions of Examples 4 to 11 containing any of the compounds of Examples 1 to 3 were the radiation sensitive of Comparative Example 1 containing the resin of Comparative Synthesis Example 1. A chemically amplified positive resist film that is more sensitive to electron beams or extreme ultraviolet light than compositions, has excellent roughness, etching resistance, and sensitivity, and can form fine patterns with high accuracy and stability. It was confirmed that the 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 pattern formation, but also excellent in roughness, and thus is useful for fine pattern formation by EB, EUV, and X-rays. 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.

Claims (5)

(A) a compound represented by the following general formula ( 2 );
(B) A radiation-sensitive composition containing a radiation-sensitive acid generator that generates an acid when irradiated with radiation.

(In the general formula (2), each R is independently a hydrogen atom or a group represented by the following general formula (3-1). However, at least one of R is represented by the following general formula (3-1) (N is an integer of 0 to 30.)

(In General Formula (3-1), R ¹ is an unsubstituted, linear, branched or cyclic alkyl group having 1 to 40 carbon atoms, and m is an integer of 0 to 3.) R ¹ in the general formula (3-1) is tert-butyl, 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, 1-ethylcyclopentyl group, or 1-methylcyclopentyl group. and radiation-sensitive composition according to claim 1 m is 0 or 1. The radiation sensitive acid generator (b) is
The radiation-sensitive composition according to claim 2 , which is at least one selected from the group consisting of an onium salt, a diazomethane compound, and a sulfonimide compound. (C) The radiation-sensitive composition according to any one of claims 1 to 3 , further comprising an acid diffusion controller. Following general formula (2) represented Ru of compounds.

(In the general formula (2), each R is independently a hydrogen atom or a group represented by the following general formula (3-1) . However, at least one of R is represented by the following general formula (3-1) ( N is an integer of 0 to 30. )

(In General Formula (3-1), R ¹ is an unsubstituted, linear, branched or cyclic alkyl group having 1 to 40 carbon atoms, and m is an integer of 0 to 3.)