JP2589803B2 - Ionizing radiation-sensitive resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial application field" The present invention relates to an ultraviolet ray, a far ultraviolet ray, an X ray comprising an alkali-soluble resin, an ionizing radiation-sensitive compound and a specific compound.
The present invention relates to an ionizing radiation-sensitive resin composition that is sensitive to radiation such as X-rays, electron beams, molecular beams, γ-rays, and synchrotron radiation, and more specifically, to fine processing excellent in resolution, sensitivity, heat resistance, and developability. The present invention relates to an ionizing radiation-sensitive resist composition for use.

Ionizing radiation-sensitive resist according to the present invention, semiconductor wafer, or glass, ceramics, on a substrate such as metal,
It is applied to a thickness of 0.1 to 10 μm by spin coating or roller coating. After that, it is heated and dried, and a circuit pattern or the like is baked by irradiation of ultraviolet rays, far ultraviolet rays, X-rays or the like through an exposure mask, or a pattern is directly drawn by an electron beam, an ion beam or the like, and developed to obtain an image. . Further, the substrate can be processed in a pattern by etching using this image as a mask. Typical application areas are
These include semiconductor manufacturing processes for ICs and the like, manufacturing of circuit boards for liquid crystals, thermal heads and the like, and other photo-fabrication processes.

"Prior art" Conventional photofabrication processes, such as the manufacture of semiconductor devices such as ICs and the manufacture of magnetic bubble memory elements, involve the use of photopolymers mainly composed of a cyclized rubber-based binder and a photosensitive crosslinking agent compound such as a bisazide compound. Resist has been used. This cyclized rubber photoresist has excellent properties in terms of adhesion to the substrate and sensitivity, but due to swelling during development, the resolution is limited, and it is extremely difficult to obtain a resolution of 3 μm or more. Atsuta.

At present, a positive photoresist composition containing an alkali-soluble resin and a naphthoquinonediazide compound as a photosensitive material is used to overcome the limitation of resolution and obtain higher resolution. For example, US Pat. No. 3,666,473, US Pat. No. 4,115,128 and US Pat. No. 4,115,128 as “Novolak-type phenol resin / naphthoquinonediazide-substituted compound”
No. 73,470, and the most typical composition is "Novolak resin composed of cresol-formaldehyde / trihydroxybenzophenone-1,2-naphthoquinonediazidesulfonic acid ester" which is described in Thompson "Introduction Toe Micro. Lithography "(LFThom
pson "Introduction to Microlithography", ACS Publishing,
No. 219, pages 112 to 121).

The novolak resin as a binder is particularly useful in this application because it can be dissolved in an alkaline aqueous solution without swelling, and gives a high resistance to plasma etching especially when the generated image is used as a mask for etching. is there.

Various radiation-sensitive resist compositions have been proposed by utilizing the excellent properties of the novolak resin.

For example, JP-A-63-250642 discloses a phenol novolak resin and a polymer having an acid labile group (eg, poly-t-butoxy-α-methylstyrene, poly-α-methylbenzyl methacrylate, poly-4-t-). Disclosed are photoresist compositions comprising butyl vinyl benzoate and the like and an onium salt (such as 4-methoxyphenylphenyliodonium trifluoromethanesulfonate).

JP-A-63-305347 discloses a negative photoresist composition comprising an alkali-soluble phenol resin and a photocrosslinking agent.

Further, JP-A-54-15357 and JP-A-59-152 disclose radiation-positive resists comprising a composition of an alkali-soluble novolak resin and polyolefin sulfone.

In spite of these many resists being proposed, developed or put into practical use, further high integration of semiconductor integrated circuits, high resolution to achieve high productivity, high sensitivity,
At present, there is no resist that satisfies various requirements of high heat resistance.

"Problems to be solved by the invention" However, integrated circuits are becoming more and more integrated,
In the manufacture of semiconductor substrates such as LSIs, it has become necessary to process an ultrafine pattern having a line width of 1 μm or less. In such applications, there is a demand for a photoresist having particularly high resolution, high pattern shape reproduction accuracy for accurately capturing the shape of an exposure mask, and high sensitivity from the viewpoint of high productivity.

Also, in order to increase the degree of integration of integrated circuits, the etching method has shifted from the conventional wet etching method to the dry etching method, but during dry etching, the temperature of the resist rises, so that thermal deformation does not occur. As described above, the resist is required to have high heat resistance. In order to improve the heat resistance of the resist, use a resin containing no component having a superimposed average molecular weight of 2000 or less (JP-A-60-97347), and use a resin having a total content of from monomer to trimer of 10% by weight or less. (Japanese Patent Application Laid-Open No. 60-189739) is disclosed.

However, when a resin from which the above low molecular weight component is removed or reduced is used, there is a problem that the sensitivity is usually lowered and the throughput in the device manufacturing is lowered.

Attempts have also been made to improve the sensitivity and developability of the resist by incorporating a specific compound into the resist composition. For example, JP-A-61-141441 discloses a positive photoresist composition containing trihydroxybenzophenone. The positive photoresist containing trihydroxybenzophenone has improved sensitivity and developability, but has the problem that the addition of trihydroxybenzophenone deteriorates heat resistance.

Accordingly, an object of the present invention is to provide an ionizing radiation-sensitive resin composition that can provide a resist pattern having high sensitivity and excellent heat resistance, particularly in the production of semiconductor devices and the like.

"Means for solving the problem" The present inventors have noted the above-mentioned properties, and as a result of intensive studies, by using an alkali-soluble resin and an ionizing radiation-sensitive compound and a compound having a specific structural formula, The inventors have found that the above object can be achieved, and have accomplished the present invention based on this finding.

That is, an object of the present invention is to provide an ionizing radiation-sensitive resin composition containing, as essential components, an ionizing radiation-sensitive compound and an alkali-soluble resin. The ionizing radiation-sensitive resin composition comprises at least one compound having a structure represented by the following formula:

 Hereinafter, the present invention will be described in detail.

In R _{1 to} R ₈ in the general formula (I), a halogen atom is chlorine, bromine or iodine, and an alkyl is methyl, ethyl, propyl, n
-Butyl group, isobutyl group, sec-butyl group or t
An alkyl group having 1 to 4 carbon atoms such as -butyl group, as an alkoxy group, a methoxy group, an ethoxy group, a hydroxyethoxy group, a propoxy group, a hydroxypropoxy group,
Isopropoxy group, n-butoxy group, isobutoxy group,
An alkoxy group having 1 to 4 carbon atoms such as sec-butoxy group or t-butoxy group, a benzyl group, a phenethyl group or a benzhydryl group as an aralkyl group, and a phenyl group, a tolyl group, or a hydroxyphenyl group as an aryl group. Group or naphthyl group, as a monoalkylamino group, a monomethylamino group, a monoethylamino group,
Monopropylamino group, monoisopropylamino group, mono n-butylamino group, monoisobutylamino group, mono
A monoalkylamino group having 1 to 4 carbon atoms such as a sec-butylamino group or a mono-t-butylamino group is a dimethylamino group, a diethylamino group, a dipropylamino group, a diisopropylamino group,
Di-n-butylamino group, diisobutylamino group, disec
Dialkylamino groups each having an alkyl substituent having 1 to 4 carbon atoms, such as -butylamino group or di-t-butylamino group, and acylamino groups such as acetylamino group, propionylamino group, butyrylamino group, and isobutyryl group; An aliphatic substituted acylamino group having 2 to 5 carbon atoms, such as an amino group, an isovalerylamino group, a pivaloylamino group, or a valerylamino group, and an aromatic substituted acylamino group, such as a benzoylamino group or a toluoylamino group, are substituted with a alkoxy group. Examples of the carbamoyl group include methylcarbamoyl, ethylcarbamoyl, propylcarbamoyl, isopropylcarbamoyl, n-butylcarbamoyl, isobutylcarbamoyl, sec-
An alkylcarbamoyl group having 2 to 5 carbon atoms such as a butylcarbamoyl group or a t-butylcarbamoyl group; a phenylcarbamoyl group or a tolylcarbamoyl group as an arylcarbamoyl group; and methylsulfamoyl as an alkylsulfamoyl group. Group, ethylsulfamoyl group, propylsulfamoyl group, isopropylsulfamoyl group, n-butylsulfamoyl group, se
An alkylsulfamoyl group having 1 to 4 carbon atoms such as a c-butylsulfamoyl group or a t-butylsulfamoyl group, and a phenylsulfamoyl group or a tolylsulfamoyl group as the arylsulfamoyl group Etc.
Examples of the acyl group include a formyl group, an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a valeryl group, an aliphatic acyl group having 1 to 5 carbon atoms such as an isovaleryl group or a pivaloyl group and a benzoyl group, a toluoyl group, a salicyloyl group or An aromatic acyl group such as a naphthoyl group is an alkyloxycarbonyl group such as a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, an isopropoxycarbonyl group, an n-butoxycarbonyl group, an isobutoxycarbonyl group, and a sec-butoxycarbonyl group. Or an alkyloxycarbonyl group having 2 to 5 carbon atoms such as a t-butoxycarbonyl group, an aryloxycarbonyl group such as an phenyloxycarbonyl group, an acyloxy group as an acetoxy group, An aliphatic acyloxy group having 2 to 5 carbon atoms such as a propionyloxy group, a butyryloxy group, an isobutyryloxy group, a valeryloxy group, an isovaleryloxy group or a pivaloyloxy group, and a benzoyloxy group, a toluoyloxy group or a naphthoyloxy group Aromatic acyloxy groups such as groups are each preferred.

Examples of the alkyl group represented by R _{9 to} R ₁₂ include an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group or a t-butyl group. Is preferred.

The compound represented by the general formula (I) can be synthesized, for example, according to the method of W. Baker et al. [J. Chem. Soc., (1939) p195-]. Specific examples are shown in Table 1 below, but are not limited thereto.

Examples of the alkali-soluble resin used in the present invention include a novolak resin, a vinylphenol resin, an acetone-pyrogallol resin, an acetone-resole resin, a maleimide copolymer, an N- (hydroxyphenyl) maleimide (co) polymer, and styrene-anhydride maleate. An methacrylic or acrylic resin containing an acid copolymer, a carboxyl group, a sulfonyl group, a phosphonic acid group, or the like can be used.

The alkali-soluble novolak resin that can be used in the present invention is obtained by condensing 0.6 to 1.0 mol of aldehydes with respect to 1 mol of phenols in the presence of an acidic catalyst. Examples of phenols include phenol, p-chlorophenol, m-cresol, p-cresol, o
-Use cresol, p-methoxyphenol, ethylphenol, resorcinol, naphthol or xylenol alone or in combination of two or more can do.

As aldehydes, formaldehyde, paraformaldehyde, acetaldehyde, chloroacetaldehyde, acrolein, mecrolein, crotonaldehyde, acrolein dimethyl acetal or furfural can be used.

As the acidic catalyst, hydrochloric acid, sulfuric acid, nitric acid, formic acid, acetic acid, oxalic acid, p-toluenesulfonic acid or the like can be used.

The thus obtained novolak resin having a molecular weight of 1,000 to 50,000 shows alkali solubility.

As the ionizing radiation-sensitive compound used in the present invention,
There are ionizing radiation-sensitive alkali dissolution inhibitor compounds and ionizing radiation-sensitive acid generator compounds. When an ionizing radiation-sensitive acid generator compound is used, it is preferable to further use an alkali dissolution inhibitor compound having an acid labile group in combination.

Examples of the ionizing radiation-soluble alkali dissolution inhibitor compound include quinonediazide compounds, diazoketone compounds, azide compounds, orthonitrobenzyl compounds, orthonitroarylsulfonylester compounds and polyolefinsulfone compounds.

Examples of the acid labile group-containing alkali dissolution inhibitor compound include tetrahydropyranyl ether compounds, t
-Butyl ether and ester compounds, or silyl ether and ester compounds. As the ionizing radiation-sensitive acid generator compound, for example, onium salts,
Organic halogen compounds, orthoquinonediazidosulfonyl chlorides, and the like. Specific compounds are listed below, but are not limited thereto.

Examples of the quinonediazide compounds include 1,2-naphthoquinonediazide-5-sulfonic acid, 1,2-naphthoquinonediazide-4-sulfonic acid, or an ester of 1,2-benzoquinonediazide-4-sulfonic acid with a polyhydroxy aromatic compound. Is used.

As the polyhydroxy aromatic compound, for example, 2,3,
4-trihydroxybenzophenone, 2,4,4'-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2, 2 ', 4,4'-tetrahydroxybenzophenone,
Polyhydroxybenzophenones such as 2,4,6,3 ', 4', 5'-hexahydroxybenzophenone, 2,3,4,3 ', 4', 5'-hexahydroxybenzophenone, Polyhydroxyphenylalkylkeons such as 2,3,4-trihydroxyacetophenone and 2,3,4-trihydroxyphenylhexyl ketone, bis (2,4-dihydroxyphenyl)
Methane, bis (2,3,4-trihydroxyphenyl) methane, bis (2,4-dihydroxyphenyl) propane-1
Bis ((poly) hydroxyphenyl) alkanes such as
Polyhydroxybenzoates such as propyl 3,4,5-trihydroxybenzoate and phenyl 3,4,5-trihydroxybenzoate, bis (2,3,4-trihydroxybenzoyl) methane, bis (2, Bis (polyhydroxybenzoyl) alkanes such as 3,4-trihydroxybenzoyl) benzene or bis (polyhydroxybenzoyl) aryls, alkylene di (polyhydroxybenzoates) such as ethylene glycol-di (3,5-dihydroxybenzoate), 3,5,3 ', 5'-biphenyl tetrol, 2,
4,2 ', 4'-biphenyl tetrol, 2,4,6,3', 5'-biphenyl pentol, 2,4,6,2 ', 4', 6'-biphenylhexol, etc. Polyhydroxybiphenyls, 4,4 ′,
3 ", 4" -tetrahydroxy-3,5,3 ', 5'-tetramethyltriphenylmethane, 4,4', 2 ", 3", 4 "-pentahydroxy-3,5,3 ', 5 Polyhydroxytriphenylmethanes such as '-tetramethyltriphenylmethane, 2,3,4,2', 3 ', 4', 3 '', 4 ''-octahydroxy-5,5'-diacetyltriphenylmethane, 3,3,3 ', 3'-tetramethyl-1,1'-spirobiindan-5,6,5', 6'-tetrol, 3,3,3 ', 3'-tetramethyl-1,1 '-Spirobi-indane-5,6,7,5', 6 ', 7'-hequinol, 3,3,
3 ', 3'-tetramethyl-1,1'-spirobiindane-4,
5,6,4 ', 5', 6'-hexol, 3,3,3 ', 3'-tetramethyl-1,1'-spirobi-indane-4,5,6,5', 6 ',
Polyhydroxyspirobi-indanes such as 7'-hexol or flavono dyes such as quercetin and rutin, alkali-soluble novolak resins, polyhydroxystyrene, and acetone-pyrogallol resins can be used.

Examples of the diazoketone compounds include 5-diazomeldrum acid, 2-diazo-1-phenylbutane-1,3-
Dione, 1,3-diphenyl-2-diazopropane-1,3-
Dione, 2-diazo-methyl, phenylmalonate, 2
-Diazo-1- (3'-chlorosulfonylphenyl)-
1-trimethylsilylpropane-1,3-dione or JP-A-60-14235, 62-47296, 63-253938, 63
-253940.

Examples of the azide compounds include 1-azidopyrene,
p-azidobenzophenone, 4'-methoxy-4-azidodiphenylamine, 4-azidobenzal-2'-methoxyacetophenone, 4-azido-4'-nitrophenylazobenzene, 1- (p-azidophenyl) -1-cyano-4- (p'-diethylaminophenyl) -1,3-
Monoazide compounds such as butadiene and 4-azidochalcone, 4,4'-diazidobenzophenone, 4,4'-diazidodiphenylmethane, 4,4'diazidostilbene, 4,4'-
Diazido chalcone, 4,4'-diazidobenzalacetone, 4,4'-diazidodiphenyl ether, 4,4'-diazidodiphenyl sulfide, 4,4'-diazidodiphenyl sulfone, 2, 6-di (4'-azidobenzal) cyclohexanone, 2,6-di (4'-azidobenzal) -4-methylcyclohexanone, 1,8-diazidonaphthalene, 3-
Azido-4 '-(3'-azidobenzalmethyl) stilbene, or JP-B-35-29295, JP-B48-31841, JP-B44-26
047, 44-26048, 45-7328, 47-30204, 49-1
2283, 51-29932, 53-325, JP-A-48-14316, 4
8-93623, 49-81103, 55-57538, 56-39538,
58-68036, 58-203438, 60-107644, 62-224
9, 63-305347, USP2852379, 2940853, 309249
4, azide compounds described in GB892811, FR1511485, DE514057 and the like.

Examples of orthonitrobenzyl compounds include orthonitrobenzyl stearate, orthonitrobenzyl cholesteric acid, orthonitrobenzyloxytriphenylsilane, 5-methyl-2-nitrobenzyltriphenylsilane, di (5-chloro-2 −
(Nitrobenzyloxy) diphenylsilane, poly-ortho-nitrobenzyl methacrylate, poly-ortho-nitrobenzyl acrylate, ortho-nitrobenzaldehyde acetal of polyvinyl alcohol, or JP-A-48-47320, JP-A-60-198538, JP-A-61-138255, 62
And orthonitrobenzyl compounds described in US Pat.

The orthonitroarylsulfenyl ester compounds include, for example, 2,4-dinitrobenzenesulfenylcholate, orthonitrobenzenesulfenyladamantanecarboxylate, orthonitrobenzenesulfenyl-tris (trimethylsilyl) cholate, poly-2, 4-Dinitrobenzenesulfenyl methacrylate, and orthonitroarylsulfenyl ester compounds described in JP-A-61-3141 and JP-A-61-36741.

Examples of polyolefin sulfon compounds include poly-butene-1-sulfone, polyhexene-1-sulfone, polycyclopentene sulfone, poly-2-methylpentene sulfone, polyoctene-1-sulfone, polybutene-2-sulfone, and 62-27732, 63-218
949 and the like.

Examples of the tetrahydropyranyl ether compounds include 4,4'-isopropylidene diphenol-bis-2.
-Tetrahydropyranyl ether, 4,4'-sulfonyldiphenol-bis-tetrahydropyranyl ether,
Examples thereof include poly-tetrahydropyranyl ether of phenol formaldehyde resin and tetrahydropyranyl ether compounds described in US Pat. No. 3,779,778.

Examples of the t-butyl ether or ester compounds include poly-pt-butoxy-α-methylstyrene, poly-pt-butoxystyrene, and poly-pt-
Butoxycarbonylstyrene, poly-pt-butoxycarbonyloxystyrene, JP-A-63-241542, JP-A-63-241542
T-butyl ether or ester compound described in No. 250642 and the like.

As silyl ether or ester compounds,
For example, trimethylsilyl benzoate, bis (trimethylsilyl) adipate, bis (dimethyl-isopropylsilyl) adipate, trimethylsilyl terephthalate, trimethylsilyl methacrylate, poly-dimethylsilyl fumarate, pt-butylphenyloxytrimethylsilane, 4,4'-isopropylidene -Bis- (trimethylsilyloxybenzene), trimethylsilylated cresol novolak resin, trimethylsilylated poly-p-hydroxystyrene, poly (dimethylsilyloxyhexamethylene ether), JP-A-60-1024
7, 60-37549, 60-121446, 61-151643, 62-
25751, 62-279326, 63-121045, 63-287949,
And silyl ether or ester compounds described in JP-A-62-153853 and the like.

The onium salts of the ionizing radiation-sensitive acid generator compound used in the present invention include, for example, diazonium (eg, p
-Chlorobenzenediazonium, etc.), iodonium (eg, diphenyliodonium, m-nitrophenylphenyliodonium, 4-methoxyphenylphenyliodonium, etc.), sulfonium (eg, triphenylsulfonium, tritolylsulfonium, benzoylmethyldimethylsulfonium, 3 BF of onium compounds such as 1,5-dimethyl-4-hydroxyphenyldimethylsulfonium, etc.), phosphonium (eg, tetraphenylphosphonium, benzoylmethyltriphenylphosphonium, etc.), and selenium (eg, triphenylselenium, etc.).
_{^{4 -, PF 6 -, SbF}} 6 -, SiF 6 -, ClO 4 -, HSO 4 -, CF 3 SO 3 - include salts and the like.

Examples of the organic halogen compounds include 2- (p-methoxyphenyl) -4,6-trichloromethyl-s-triazine and 2-trichloromethyl-5- (p-methoxystyryl) -1,3,4-oxa. Diazole, 2,4-bis (trichloromethyl) -6- (4-methoxystyryl) -s-
Triazine, hexabromoethane, 2-trichloromethyl-5- (p-chlorostyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (3'-methoxy-4'-benzyloxystyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5- [2- (4-methoxynaphthyl) -ethenyl] -1,3,4-oxadiazole, 2-trichloromethyl-5- (4 -Styrylstyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (4-styrylphenyl) -1,3,4-oxadiazole, 1,3-bis-trichloromethyl-5- ( 4
-Methoxyphenyl) -s-triazine, 1,3-bis-
Trichloromethyl-5- (4-methoxynaphthyl) -s
-Triazine, JP-A-61-169837, USP3779778, DE2610
And organic halogen compounds described in 842 and the like.

Examples of orthoquinonediazidosulfonyl chlorides include 1,2-naphthoquinonediazide-4-sulfonyl chloride, 1,2-naphthoquinonediazide-5-sulfonylchloride, 1,2-benzoquinonediazide-4-sulfonylchloride, N- (1, 2-naphthoquinone-2-diazido-4-sulfonyloxy) phthalimide.

The use ratio of the compound represented by the general formula (I) and the alkali-soluble resin used in the present invention is 10%.
0.1 to 60 parts by weight of the compound of the general formula (I) based on 0 parts by weight,
Preferably it is 1 to 25 parts by weight.

If the use ratio is less than 0.1 part by weight, the effect of increasing sensitivity is not substantially obtained, and if it exceeds 60 parts by weight, the residual film ratio is remarkably reduced.

The use ratio of the alkali dissolution inhibitor compound and the alkali-soluble resin in the present invention is 5 to 100 parts by weight, preferably 10 to 50 parts by weight of the alkali dissolution inhibitor compound per 100 parts by weight of the resin.
Parts by weight. If the use ratio is less than 5 parts by weight, the residual film ratio is remarkably reduced, and if it exceeds 100 parts by weight, sensitivity and solubility in a solvent are reduced.

When an ionizing radiation-sensitive acid generator compound is used, the ionizing radiation-sensitive acid generator compound is used in an amount of 0.1 to 200 parts by weight, preferably 1 to 100 parts by weight, based on the acid labile group-containing alkali dissolution inhibitor compound. Use in the range of 60 parts by weight. If this ratio is less than 0.1 part by weight, the sensitivity is significantly reduced.

In the present invention, a polyhydroxy compound can be further contained to promote dissolution in a developer. Preferred polyhydroxy compounds include phenols, resorcin, phloroglucin, 2,3,4-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, pentahydroxybenzophenone, hexahydroxybenzophenone, acetone- Pyrogallol condensation resin, phloroglucid and the like are included.

Examples of the solvent for dissolving the photosensitive material of the present invention and the alkali-soluble novolak resin include ketones such as methyl ethyl ketone and cyclohexanone; alcohol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; ethers such as dioxane and ethylene glycol dimethyl ether. Cellosolve esters such as methyl cellosolve acetate and ethyl cellosolve acetate; fatty acid esters such as butyl acetate, methyl lactate and ethyl lactate; halogenated hydrocarbons such as 1,1,2-trichloroethylene; dimethylacetamide;
-Highly polar solvents such as methylpyrrolidone, dimethylformamide and dimethylsulfoxide can be exemplified.
These solvents can be used alone or as a mixture of a plurality of solvents.

The ionizing radiation-sensitive resin composition of the present invention may optionally contain a dye, a plasticizer, an adhesion aid, a surfactant, and the like. Specific examples include dyes such as methyl violet, crystal violet, and malachite green; plasticizers such as stearic acid, acetal resins, phenoxy resins, and alkyd resins; and adhesion promoters such as hexamethyldisilazane and chloromethylsilane. And surfactants such as nonylphenoxypoly (ethyleneoxy) ethanol and octylphenoxypoly (ethyleneoxy) ethanol.

The above ionizing radiation-sensitive resin composition is applied on a substrate (eg, silicon / silicon dioxide coating) used for manufacturing precision integrated circuit devices by a suitable application method such as a spinner or a coater, and then passed through a predetermined mask. By exposing and developing, a good resist can be obtained.

When the azide compound is used as the alkali dissolution inhibitor compound, the ionizing radiation-sensitive resin composition of the present invention can obtain a so-called negative pattern in which a portion irradiated with ionizing radiation usually remains as an image.

When an alkali dissolution inhibitor compound other than the azide compound is used, a so-called positive pattern image in which a portion not normally irradiated with ionizing radiation is formed as an image is obtained. However, even in the latter case, JP-A-63-3164
29, etc., a heat treatment in an amine atmosphere, or JP-A-62-35350. 2,263-di-t-butylpyridine, benzimidazole, pyridine, quinoline, acridine, lutidine, 1-
By blending a compound such as methylbenzimidazole or melamine formaldehyde alkyl ether into the resin composition of the present invention, a negative pattern can be effectively obtained by performing image reversal.

Examples of the developer for the ionizing radiation-sensitive resin composition of the present invention include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, inorganic alkalis such as aqueous ammonia, ethylamine, n-propylamine and the like. Primary amines, diethylamine, di-n-
Secondary amines such as butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, and quaternary amines such as tetramethylammonium hydroxide, tetraethylammonium hydroxide and choline hydroxide. Aqueous solutions of alkalis such as quaternary ammonium salts, cyclic amines such as pyrrole and piperidine can be used. Further, an appropriate amount of an alcohol or a surfactant may be added to the aqueous solution of the above alkalis for use.

[Effect of the Invention] The ionizing radiation-sensitive resin composition of the present invention has excellent resolution, sensitivity, and developability, has excellent heat resistance, and is suitably used as a photoresist for fine processing.

"Examples" Hereinafter, the present invention will be described based on examples, but the present invention is not limited thereto. In addition, the weight average molecular weight was measured as follows.

The measurement was carried out using gel permeation chromatography (GPC) at 40 ° C., a flow rate of 1 ml / min, a THF solvent, and a detection wavelength of 282 nm. The column used was TSKgelGM manufactured by Toyo Soda Kogyo.
H, G4000H, G3000H, and G2000H were connected one by one, and the weight average molecular weight was calculated using monodisperse polystyrene as a standard.

Synthesis Examples (1) to (5) (1) Synthesis of Compound 4 Pyrogallol 42 g, acetone 33 g, acetic acid 80 ml, and concentrated sulfuric acid
64 ml was charged into a three-necked flask and uniformly dissolved under stirring. The mixture was heated in an aqueous solution, refluxed for 24 hours, and then cooled to room temperature. After cooling, the reaction solution was dropped into 2000 ml of distilled water, and the product was separated in a precipitation oven, dried under reduced pressure, and dried under reduced pressure.
3'-tetramethyl-1,1'-spirobi-indane-5,6,
7,5'6 ', 7'-Hexool was obtained.

(2) Synthesis of compound 8, 3,3,3 ', 3'-tetramethyl-1,1'-spirobi-yl, using pyrocatechol and acetone, in the same manner as for compound 4.
Indane-5,6,5 ', 6'-tetrol was obtained.

(3) Synthesis of compound 19 Using 1,2,4, -triacetoxybenzene and acetone,
4,4,4 ′, 4′-Tetramethyl-
2,2'-spirobi-chroman-6,7,6 ', 7'-tetrol was obtained.

(4) Synthesis of novolak resin (a) 40 g of m-cresol, 60 g of p-cresol, 54.0 g of 37% aqueous solution of formalin and 0.05 g of oxalic acid were charged into a three-necked flask, and heated to 100 ° C. while stirring. Allowed to react for hours. After the reaction, the mixture was cooled to room temperature, and the pressure was reduced to 30 mmHg.

Then, the temperature was gradually raised to 150 ° C. to remove water and unreacted monomers. The resulting novolak resin has an average molecular weight of 79
00 (in terms of polystyrene).

(5) Synthesis of novolak resin (b) A cresol novolak resin (polystyrene-equivalent molecular weight of 10%) synthesized using 60% by weight of meta-cresol, 40% by weight of para-cresol and formalin in the same manner as in (4) above.
200), referring to “Experimental Methods for Polymer Synthesis,” p. 32 (Masetsu Kinoshita and Takayuki Otsu: Chemical Doujinshi (1973)) to separate low-molecular-weight components to obtain cresol novolak resin with a molecular weight of 13600 in terms of polystyrene. Obtained.

Examples 1 to 9 Each compound was dissolved in a solvent under the conditions described in Table 2 and 0.2 μm
Was filtered through a microfilter to prepare a resist composition.

In addition, in Example 9, the poly-
t-butoxy-α-methylstyrene 2. 2 g were added.

The resist composition was applied on a silicon wafer having an oxide film of 250 nm using a spinner, and dried in a convection oven under a nitrogen atmosphere at 90 ° C. for 30 minutes to form a film having a thickness of 1.5 μm.
Was obtained. After exposing this film through a test chart using a reduction projection exposure apparatus manufactured by Nikon Corporation, 2.38
The resist was developed with a 1% by weight aqueous solution of tetramethylammonium hydroxide for 1 minute and rinsed with ion-exchanged water to obtain a resist pattern. The resist pattern on the silicon wafer thus obtained was observed with a scanning electron microscope to evaluate the resist pattern. Table 4 shows the results.

The sensitivity was defined as the reciprocal of the exposure amount for reproducing a 2.0 μm mask pattern, and was shown as a relative value to the sensitivity of Comparative Example 2.

The resolving power was indicated by the line width of the smallest resolved mask pattern at the exposure dose for reproducing a 2.0 μm mask pattern.

The heat resistance is shown by a temperature at which deformation of the resist pattern starts when the silicon wafer on which the resist pattern is formed is baked at a predetermined temperature for 4 minutes using a vacuum suction type hot plate.

Comparative Examples 1 to 5 Samples were prepared and evaluated in the same manner as in Examples 1, 2, 3, and 4 except that the compound of the general formula (I) was omitted. Further, a sample was prepared and evaluated in the same manner as in Example 1 except that 2,3,4-trihydroxybenzophenone was used instead of the compound 4 of Example 1, and Comparative Example 5 was obtained. Table 4 shows the results.

As can be seen, the ionizing radiation-sensitive resin composition of the present invention can achieve high sensitivity without a decrease in resolution and heat resistance.

Example 10 and Comparative Example 6 Each compound was dissolved in a solvent under the conditions described in Example 10 of Table 2, and filtered through a 0.2 μm microfilter to prepare a resist composition.

A resist composition was prepared in the same manner as in Example 10 except that Compound Example 4 was omitted. did.

These resist compositions were applied and dried in the same manner as in Example 1 to obtain a resist film having a thickness of 0.5 μm. Using an electron beam irradiator on this wafer, 0.5-30 μC / c at an acceleration voltage of 20 KV
Stepwise exposure was performed with an incident dose of m ² . This was subjected to immersion development for 60 seconds with an FHD-5 developer manufactured by Fuji Hunt to obtain a positive pattern.

The resist sensitivity and the γ value were determined by plotting the amount of the remaining resist film with respect to the exposure amount.

The results are shown in the table below.

As is clear from this, the resist of the present invention is excellent in both sensitivity and heat resistance.

Claims (5)

(57) [Claims] 1. An ionizing radiation-sensitive resin composition comprising an ionizing radiation-sensitive compound and an alkali-soluble resin as essential components. An ionizing radiation-sensitive resin composition comprising at least one compound having a structure represented by the formula: 2. The ionizing radiation-sensitive resin composition according to claim 1, wherein said ionizing radiation-sensitive compound is a quinonediazide compound or a diazoketone compound. 3. The ionizing radiation-sensitive resin composition according to claim 1, wherein said ionizing radiation-sensitive compound is a 1,2-naphthoquinonediazidosulfonic acid ester compound. 4. An ionizing radiation-sensitive resin composition according to claim 3, wherein said alkali-soluble resin is a phenol, cresol, xylenol or a novolak resin synthesized from a mixture of two or more thereof. . 5. The ionizing radiation-sensitive resin composition according to claim 1, wherein said R _{1 to} R ₈ are each independently a hydrogen atom, a hydroxyl group, an alkoxy group or an acyloxy group.