JPH0943839A - Reflection preventing film forming composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a reflection preventing film forming composition excellent in stable preservation and free from sublimation in a baking process and a dry etching process by dispersing non-sublimating fine particles having radiation absorbability in an organic solvent. SOLUTION: This reflection preventing film forming composition contains the non-sublimating fine particles having radiation absorbability, a high molecular dispersant and the organic solvent and the non-sublimating fine particles are dispersed in the organic solvent. As the non-sublimating fine particles having radiation absorbability, for example, the fine particles of an organic pigment such as azo base, phthalocyanine base and the fine particles of an inorganic pigment such as titanium oxide, carbon are mentioned. As the high molecular dispersant, an ethylene oxide.propylene oxide mixed addition material of sorbitol or a salt of a copolymer of a carboxyl group-containing unsaturated monomer and other vinyl compound is preferable. As the organic solvent, for example, 2-methoxyethyl acetate, ethylene glycol monomethyl ether or the like is mentioned.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a composition for forming an antireflection film, which is useful for fine processing in a lithographic process using various kinds of radiation and is particularly suitable for manufacturing integrated circuit devices.

[0002]

2. Description of the Related Art In the field of manufacturing integrated circuit elements, in order to obtain a higher degree of integration, the processing size in the lithography process is becoming finer, and in recent years, fine processing in the sub-half micron order has become possible. The technology to do so is being developed. In this lithographic process, generally, a resist such as a positive resist composed of a novolac resin and a quinonediazide-based photosensitizer is used.
A desired resist pattern is obtained by coating the substrate with a thickness of 0.5 to 10 μm, transferring the mask pattern by a reduction projection exposure device (stepper), and developing with a suitable developing solution. However, aluminum, aluminum-silicon alloys, aluminum-silicon-copper alloys, polysilicon, used in this process,
On the substrate surface with high reflectance such as tungsten silicide,
In addition, depending on the irradiation wavelength (for example, deep ultraviolet rays), even on the surface of another substrate such as silicon, the exposed radiation is reflected and halation occurs, so that the radiation reaches the area that should not be exposed and a fine resist pattern is formed. There is a problem that it cannot be reproduced accurately. In order to solve this problem, conventionally, a method of adding a radiation absorber such as a dye to a positive resist to lower the radiation transmittance of the resist and suppressing reflection on the substrate surface during exposure has been attempted. There is. However, in the method of adding such a radiation absorber,
Since the exposed radiation cannot sufficiently reach the deep part of the resist film, the shape of the resist pattern is inferior, the sensitivity, resolution, depth of focus, developability, etc. are lowered, and the storage stability of the resist is also impaired. However, there is a problem that the resist performance is deteriorated. Therefore, as an alternative to the above method, a method has been proposed in which an antireflection film that absorbs exposed radiation is formed on the surface of a substrate having a particularly high reflectance to suppress reflection and prevent halation. As such an antireflection film, a titanium film, a titanium dioxide film, which is formed by a method such as vacuum deposition, CVD, or sputtering,
Inorganic materials such as titanium nitride film, chromium oxide film, carbon film and α-silicon film are known. These inorganic antireflection films have excellent followability to the steps on the substrate surface, can form a uniform film, and are mixed with the resist film (this is called intermixing). ), There is an advantage that the resolution and developability of the resist are not deteriorated, but since it has conductivity, it cannot be used in the production of integrated circuits, or it is used in a vacuum deposition apparatus, a CVD method for forming an antireflection film. There is a drawback that special equipment such as equipment and sputtering equipment is required. On the other hand, an organic antireflection film composed of a polyamic acid (co) polymer or sulfone (co) polymer and a dye has also been proposed (see, for example, Japanese Patent Laid-Open No. 59-93448). The film has no conductivity and can be coated on a substrate by dissolving in a suitable solvent by the same method as the resist without using a special device. However, in the organic antireflection film, (a) a part of the dye sublimes from the antireflection film during the baking and dry etching steps, so that the antireflection effect is lowered or the film component is sublimated. Since it causes contamination and (b) intermixes with the resist, the resolution and developability of the resist are reduced. (C) Antireflection when transferring the resist pattern to the antireflection film by dry etching after development. Since the etching rate of the film is equal to or lower than the etching rate of the resist, there is a problem that the resist pattern is damaged and accurate pattern transfer cannot be performed.

[0003]

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to overcome the above-mentioned problems of the conventional inorganic and organic antireflective coatings, to have good storage stability, and to perform the baking and dry etching processes. It is possible to form a resist pattern excellent in heat resistance, dry etching property, resolution, precision, etc. in cooperation with a positive type and a negative type photoresist without sublimating to the surface and without intermixing with the photoresist. Another object of the present invention is to provide a composition for forming an antireflection film used for manufacturing an integrated circuit device.

[0004]

The gist of the present invention is that (a)
A non-sublimable fine particle having radiation absorbency, (b) a polymer dispersant, and (c) an organic solvent, wherein the non-sublimable fine particle is dispersed in an organic solvent. The composition for forming an antireflection film used in production.

Hereinafter, the present invention will be described in detail. This will clarify the objects, configurations and effects of the present invention. The non-sublimable fine particles having a radiation absorbing property (hereinafter, simply referred to as “light absorbing fine particles”) used in the present invention are the radiation exposed during the formation of a resist pattern and the radiation reflected on the substrate surface. Fine particles that can effectively absorb, but do not substantially sublime at least in all steps of forming a resist pattern and are substantially insoluble in the solvent used. However,
The color tone of the light absorbing fine particles is not particularly limited as long as the particles have the above-mentioned characteristics. Examples of such light absorbing fine particles include fine particles of organic pigments such as azo, phthalocyanine, triphenylmethane, quinoline, quinacridone, dioxazine, perylene, isoindolinone, and anthraquinone; oxidation. Examples thereof include fine particles of inorganic pigments such as titanium, lead chromate, lead sulfate, yellow lead, zinc yellow, red iron oxide (red iron (III) oxide), cadmium red, titanium black, iron black, and carbon. As such light absorbing fine particles, particularly fine particles of carbon are preferable, and examples of the material thereof include oil furnace black, channel black, thermal black, acetylene black, lamp black, bone black, mineral black, aniline black, graphite. Such as carbon black, fullerene C ₆₀ , fullerene C
₇₀ , fullerenes such as fullerene nanotubes, and the like. The average particle size of the light absorbing fine particles is not particularly limited as long as a predetermined antireflection film can be formed on the substrate, but is usually 2 μm or less, preferably 1
nm to 1 μm, particularly preferably 1 nm to 0.1 μm. In this case, when the average particle diameter exceeds 2 μm, the smoothness of the antireflection film is impaired, and the dispersibility in an organic solvent is lowered, so that the storage stability tends to be insufficient.

Examples of the polymer dispersant used in the present invention include polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers,
Polyethylene glycol diesters, sorbitol ethylene oxide adducts, sorbitol propylene oxide adducts, sorbitol ethylene oxide
Propylene oxide mixed adducts, polyethylene polyamine ethylene oxide adducts, polyethylene polyamine propylene oxide adducts, polyethylene polyamine ethylene oxide / propylene oxide adducts, nonylphenyl ether formalin condensate ethylene oxide adducts, poly ( (Meth) acrylic acid salts, copolymer salts of carboxyl group-containing unsaturated monomers with other vinyl compounds, partial alkyl esters of poly (meth) acrylic acid or salts thereof, polystyrene sulfonates, and naphthalene sulfonate formalin condensation Products, polyalkylene polyamines, sorbitan fatty acid esters, fatty acid modified polyesters, polyamide, 3
Examples include primary amine-modified polyurethanes, tertiary amine-modified polyesters, and the like. These polymer dispersants can be used alone or in admixture of two or more. Among the above-mentioned polymer dispersants, preferred are sorbitol ethylene oxide / propylene oxide mixed adducts, copolymer salts of carboxyl group-containing unsaturated monomer and other vinyl compounds, tertiary amine-modified polyesters, and the like. Can be mentioned. The blending amount of the polymer dispersant is usually 10 to 200 parts by weight, preferably 50 to 150 parts by weight, and more preferably 80 to 120 parts by weight, per 100 parts by weight of the light absorbing fine particles. In this case, if the compounding amount of the polymer dispersant is less than 10 parts by weight, the film formability at the time of spin coating of the antireflection film-forming composition tends to decrease, and if it exceeds 200 parts by weight, the resist film is formed. Since the content ratio of the light-absorbing fine particles therein is small, the antireflection effect may be insufficient.

Examples of the organic solvent used in the present invention include 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 3-methoxypropyl acetate, 3-methoxybutyl acetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether. , Ethylene glycol monopropyl ether,
Ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methyl ethyl ketone , 2-heptanone, 3-heptanone, 4-heptanone, cyclohexanone, dioxane, tetrahydrofuran, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate,
Ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutyrate, 3-methyl-3-methoxybutyl acetate, 3-methoxybutyl propionate, 3-propionate Methyl-3-methoxybutyl, 3-methoxybutyl butyrate, 3-methyl-3-methoxybutyl butyrate, diglyme, ethyl acetate, propyl acetate, butyl acetate, 3
-Methyl methoxypropionate, methyl 3-methoxybutyrate, methyl pyruvate, ethyl pyruvate, toluene,
Examples thereof include xylene, cyclohexane, water and the like. These organic solvents may be used alone or in admixture of two or more. The organic solvent, if desired, for example, benzyl ethyl ether, dihexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, acetonylacetone, isophorone, caproic acid, caprylic acid, 1- Octanol, 1-nonanol,
Benzyl alcohol, benzyl acetate, ethyl benzoate,
One or more high boiling point organic solvents such as diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, phenyl cellosolve acetate and N-methylpyrrolidone may be added. The compounding amount of the organic solvent is usually 1 to 5 per 1 part by weight of the light absorbing fine particles.
The amount is 00 parts by weight, preferably 10 to 100 parts by weight.

Further, various additives may be added to the composition for forming an antireflection film of the present invention, as long as the desired effects are not impaired. Examples of the additives include radiation absorbing compounds other than the light absorbing fine particles (hereinafter referred to as "other light absorbing agents"), polymer binders, reactive diluents, and the like. The other light absorbing agent has a function of further improving the antireflection effect of the antireflection film. Such other light absorbers include, for example, oil-soluble dyes, disperse dyes, basic dyes, methine dyes, pyrazole dyes, imidazole dyes, hydroxyazo dyes and the like; bixine derivatives, norbixin, stilbene. , 4,4-diaminostilbene derivatives, coumarin derivatives, pyrazoline derivatives, and other fluorescent whitening agents; hydroxyazo dyes, TINUVIN 234 (manufactured by Ciba Geigy), and UV absorbers such as TINUVIN 1130 (manufactured by Ciba Geigy). it can. These other light absorbers may be used alone or in combination of two or more. The amount of the other light absorbing agent to be added is usually 100 parts by weight or less, preferably 50 parts by weight or less, per 100 parts by weight of the light absorbing fine particles.

The polymer binder has the function of holding the light absorbing fine particles in the antireflection film and improving the film strength of the antireflection film. Examples of such polymer binders include epoxy resins, melamine resins, urea resins, aniline resins, phenol resins, unsaturated polyester resins, (meth) acrylic acid ester-based resins, styrene-based resins, maleimide-based resins, and the like, A copolymer of at least one macromonomer having a polymerizable unsaturated group at one end of the polymer chain and at least one other unsaturated monomer (hereinafter referred to as "macromonomer binder"). ) And the like, and a macromonomer binder is particularly preferable. Examples of the macromonomer in the macromonomer-based binder include polystyrene, poly (meth) acrylate, ethyl poly (meth) acrylate, butyl poly (meth) acrylate, benzyl poly (meth) acrylate, and polysiloxane. The compound having a (meth) acryloyl group at one end of the polymer chain can be mentioned. Other unsaturated monomers copolymerized with the macromonomer include, for example, methyl (meth) acrylate, ethyl (meth) acrylate,
Propyl (meth) acrylate, butyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate , (Meth) acrylic acid esters such as dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, and glycidyl (meth) acrylate;
Acrylic acid, methacrylic acid, crotonic acid, maleic acid,
Unsaturated carboxylic acids such as monomethyl maleate, fumaric acid, monomethyl fumarate, itaconic acid, citraconic acid, mesaconic acid and cinnamic acid; aromatic vinyl compounds such as styrene, α-methylstyrene, vinyltoluene and styrenesulfonic acid And vinyl cyanide compounds such as (meth) acrylonitrile, α-chloroacrylonitrile and vinylidene cyanide; conjugated dienes such as butadiene, isoprene, 2,3-dimethylbutadiene, chloroprene and isoprene sulfonic acid. Such a macromonomer-based binder has a high affinity between the macromonomer unit and the light-absorbing fine particles, and can form a particularly excellent antireflection film. The polymer binders may be used alone or in admixture of two or more. The compounding amount of the polymer binder is 1
It is usually 100 parts by weight or less, preferably 1 to 50 parts by weight, per 00 parts by weight.

The above-mentioned reactive diluent is a component which is miscible with the organic solvent used in the composition for forming an antireflection film, and which can be polymerized or crosslinked by baking the composition after application or exposure to radiation. And, like the polymer binder, has an action of improving the film strength of the antireflection film. Examples of such reactive diluents include:
Vinyl ester compounds, vinyl cyanide compounds, unsaturated carboxylic acid esters, esters of unsaturated carboxylic acids and unsaturated alcohols, halogenated vinyl compounds, hydroxyl group-containing vinyl compounds, amino group-containing vinyl compounds, Amide group-containing vinyl compound, carboxyl group-containing vinyl compound, epoxy group-containing vinyl compound,
Unsaturated compounds such as aromatic vinyl compounds, polyfunctional epoxy compounds and the like can be mentioned, and esters of unsaturated carboxylic acids and polyhydric alcohols, polyfunctional epoxy compounds and the like are particularly preferable. Examples of the esters of unsaturated carboxylic acids and polyhydric alcohols include ethylene glycol, propylene glycol, butanediol,
Examples thereof include poly (meth) acrylates of dihydric or higher polyhydric alcohols such as hexanediol, polyethylene glycol, polypropylene glycol, glycerin, 1,2,4-butanetriol, trimethylolpropane and pentaerythritol. Examples of the functional epoxy compound include polyglycidyl ethers of polyhydric alcohols having two or more valences; polyglycidyl ethers of polyhydric phenolic compounds such as resorcinol, bisphenol A, and novolac resins; polyphthalic acid and terephthalic acid. Examples thereof include polyglycidyl esters of carboxylic acids. The reactive diluents may be used alone or in combination of two or more. The content of the reactive diluent is usually 100 parts by weight or less, preferably 50 parts by weight or less, per 100 parts by weight of the light absorbing fine particles. As other additives, a storage stabilizer,
An antiseptic agent, a defoaming agent, an adhesion aid and the like can be added.
The antireflection film-forming composition of the present invention thus obtained usually has a solid content concentration of, for example, 3 to 20% by weight,
After being prepared so as to be preferably 3 to 10% by weight,
A pore size larger than the particle size of the light absorbing fine particles, for example 2.5 μ
It is filtered with a filter of about m to be used for forming a resist pattern.

Next, a method for forming a resist pattern using the composition for forming an antireflection film of the present invention will be described. As a method of forming a resist pattern, for example,
(1) a step of applying a composition for forming an antireflection film on a substrate to form an antireflection film, (2) a step of applying a photoresist solution on the antireflection film to form a photoresist film,
And (3) a method of exposing the photoresist film and then developing it. In the step (1), the coating of the composition for forming an antireflection film can be performed by spin coating, cast coating or the like.
The spin coating method is adopted. Further, when the antireflection film is formed after coating the composition for forming an antireflection film, it is usually baked at an appropriate temperature to volatilize the organic solvent in the composition.
The baking temperature at that time is, for example, about 90 to 250 ° C., and the baking time is, when a hot plate is used,
For example, about 1 to 5 minutes, and when using an oven, for example, about 10 to 60 minutes. The thickness of the antireflection film thus formed is usually 0.05 to 1 μm, preferably 0.05 to 0.5 μm. Next, in the step (2) described above, the photoresist solution is prepared by adding each component constituting the photoresist in an appropriate solvent to give a solid content concentration of, for example, 5%.
It is prepared by dissolving it so that the concentration becomes ˜50 wt%, and then filtering with a filter having a pore size of about 0.2 μm, for example.
When applying the obtained photoresist solution, a method similar to the applying method in the step (1) is usually used. Further, after applying the photoresist solution, it is usually prebaked to volatilize the solvent in the solution. The pre-bake temperature at that time is appropriately adjusted according to the type of photoresist used, but is usually about 30 to 200 ° C., preferably 5
The pre-bake time is, for example, about 1 to 5 minutes when using a hot plate, and is about 10 to 60 minutes when using an oven. The dry film thickness of the photoresist film thus formed is, for example, about 0.5 to 2 μm. Needless to say, a commercially available photoresist solution can be used as the photoresist solution used in the step (2). Examples of the photoresist used when forming the photoresist film include, for example, a positive resist composed of an alkali-soluble resin and a quinonediazide-based photosensitizer, a negative resist composed of an alkali-soluble resin and a radiation-sensitive crosslinking agent, and a radiation-sensitive resist. Examples thereof include positive or negative chemically amplified resists containing an acid generator. Further, in the step (3), the radiation used for the exposure may be visible light, ultraviolet light, deep ultraviolet light, X-ray, depending on the type of photoresist.
Rays, electron rays, γ rays, molecular beams, ion beams, etc. are appropriately selected, but preferably ultraviolet rays such as i rays (wavelength 365 nm), g rays (wavelength 436 nm), and KrF excimer laser (wavelength 248 nm), It is far ultraviolet rays such as ArF excimer laser (wavelength 193 nm). The exposure is usually performed using a stepper through a predetermined mask pattern. Then, it is developed, washed and dried to form a desired resist pattern. During this process,
In order to further improve the resolution, pattern shape, developability, etc., bake after exposure may be performed. Examples of the developer used for the development after exposure include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, propylamine, diethylamine, dipropylamine, triethylamine, methyldiethylamine. , Dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo- [5,4,0] -7-undecene, 1,5-
An alkaline aqueous solution in which diazabicyclo- [4,3,0] -5-nonene or the like is dissolved can be used. Further, a water-soluble organic solvent, for example, alcohols such as methanol and ethanol, or a surfactant may be added to these developers in an appropriate amount. When an alkaline aqueous solution is used as the developer, it is usually washed with water after development. Then, using the formed resist pattern as a mask, dry etching of the antireflection film is performed using gas plasma such as oxygen plasma to obtain a resist pattern for substrate processing.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in more detail below with reference to examples. However, the present invention is not limited to these embodiments at all unless it exceeds the gist. The types of resist used in each example and comparative example are as follows. Types of resist Resist A: A positive resist (commercial name PFR IX120, manufactured by Nippon Synthetic Rubber Co., Ltd.) composed of a novolac resin and a naphthoquinonediazide-5-sulfonic acid ester-based photosensitizer. Resist B: Polyhydroxystyrene in which 50% of hydroxyl groups were t-butoxycarbonylated (weight average molecular weight = 1
100,000 parts by weight, triphenylsulfonium hexafluoroantimonate (radiation-sensitive acid generator)
After uniformly mixing 2 parts by weight and 306 parts by weight of propylene glycol methyl ether acetate, the pore size was adjusted to 0.
A chemically amplified positive resist consisting of a solution filtered through a 2 μm membrane filter. The resist pattern was formed by the following method. Formation of resist pattern A silicon wafer (diameter: 4 inches) on which aluminum was sputtered to a thickness of 0.2 μm was spin-coated with a composition for forming an antireflection film to a thickness of 0.2 μm to form an antireflection film. After forming, it was baked on a hot plate at 170 ° C. for 2 minutes. After that, a resist was spin-coated on the antireflection film to a film thickness of 1.5 μm to form a resist film, which was then prebaked on a hot plate at 90 ° C. for 2 minutes. Next, as a reduction projection exposure device, in the case of resist A, stepper NSR1505i6A manufactured by Nikon Corporation (numerical aperture = 0.45, wavelength = 36)
5 nm), and in the case of resist B, stepper NSR1505EX manufactured by Nikon Corporation (numerical aperture = 0.42,
Using a wavelength of 248 nm, exposure was performed for an exposure time (hereinafter referred to as “optimum exposure time”) for forming a line-and-space pattern of 0.6 μm with a line width of 1: 1. Then, after post-exposure baking on a hot plate at 110 ° C. for 1 minute, the resist pattern was developed by using a 2.38 wt% tetramethylammonium hydroxide aqueous solution at 25 ° C. for 1 minute, washed with water, and dried. Was formed.

The performance of the antireflection film was evaluated by the following method. Performance Evaluation of Antireflection Film Antireflection Effect: An antireflection film-forming composition was spin-coated on an aluminum substrate having a hole pattern with a depth of 0.6 μm and a diameter of 2 μm to a film thickness of 0.2 μm, After forming the antireflection film, prebaking was performed on a hot plate at 170 ° C. for 2 minutes. Then, a resist solution was spin-coated on the antireflection film in the same manner as in the formation of the resist pattern to form a resist film. Then, the central portion of the hole pattern is exposed for an optimum exposure time to form a line pattern having a width of 1 μm, and the depth of “excavation” due to reflection of the pattern at the optimum exposure time (hereinafter referred to as “notching depth”). ) Was investigated. 1μ
The antireflection effect is "excellent" when the ratio of the notching depth to the m-width line pattern is less than 10%, 1
When it is 0 to 20%, the antireflection effect is “good”, 20%
The antireflection effect was judged to be "poor" when it exceeded. Sublimation resistance: A composition for forming an antireflection film was spin-coated on a quartz glass substrate to a film thickness of 0.2 μm to form an antireflection film, and then prebaked on a hot plate at 150 ° C. for 1 minute. did. Then, using a self-recording spectrophotometer U-3210 manufactured by Hitachi, Ltd., the absorbance (A) at the absorption maximum (λmax) at a wavelength of 300 nm or more is measured, and then 5 on a hot plate at 180 ° C. It was prebaked for a minute, and the absorbance (B) was measured in the same manner as above. (A−B) × 100 / A is the sublimation rate (%), and when the value is 3% or less, the sublimation resistance is “good”, 3
The sublimation resistance was judged to be "poor" when it exceeded%. Intermixing (resolution): formation of an antireflection film and a resist film in the same manner as in the evaluation of the antireflection effect,
Pre-baking, exposure and development were performed, and the size of the minimum resolved resist pattern was measured using a scanning electron microscope. Intermixing (developing property): formation of an antireflection film and a resist film in the same manner as in the evaluation of the antireflection effect,
Prebaking, exposure, and development were performed, and the degree of scum and residual development due to the residue of the antireflection film or the resist film was examined using a scanning electron microscope. Heat resistance: After forming a resist pattern, baking was performed for 2 minutes on a hot plate at 140 ° C., and the presence or absence and degree of pattern deformation were examined using a scanning electron microscope. Dry etching property: An antireflection film and a resist film, which are separately formed in the same manner as the formation of the resist pattern, are dry-etched by oxygen plasma using a dry etching apparatus DEM-451 (manufactured by Niden Anerva Co., Ltd.). The pressure was 15 Pa, the RF power was 300 W, and the etching gas was oxygen. The etching rate ratio P between the antireflection film and the resist film was calculated by the formula P = Ra / Rr. Where Ra is the etching rate of the antireflection film, R
r is the etching rate of the resist film. P is 1.5
The dry etching property is "excellent" when it exceeds 0.9,
When the dry etching property was 1.5, the dry etching property was judged to be “good”, and when it was less than 0.9, the dry etching property was judged to be “poor”. Storage stability: 25 of composition for forming antireflection film immediately after preparation
The viscosity (C) at ° C was measured using an E-type viscometer (manufactured by Tokyo Keiki Co., Ltd.), and the composition for forming an antireflection film was stored at room temperature for 3 months, and then the viscosity (C) was measured in the same manner as above. D) was measured. The storage stability index (%) is defined as (D−C) × 100 / C. When the value is less than 2%, the storage stability is “excellent”, and when it is 2 to 5%, the storage stability is “ When the storage stability was “good” or more than 5%, the storage stability was judged as “poor”.

[0014]

【Example】

Examples 1 to 10 The antireflection film-forming composition used in each example was prepared according to the following formulation. Here, parts are based on weight. Formulation A Carbon black (average particle size 40 nm, trade name: Mitsubishi carbon black # 20B, manufactured by Mitsubishi Chemical Co., Ltd.) 40 parts Tertiary amine-modified polyurethane dispersant 40 parts t-butyl methacrylate / glycidyl methacrylate / poly Methylmethacrylate macromonomer copolymer (monomer composition (parts) = 65/25/15) 20 parts Methyl 3-methoxypropionate 900 parts Formulation B carbon black (average particle size 40 nm, trade name: Mitsubishi carbon black # 20B, manufactured by Mitsubishi Chemical Co., Ltd. 40 parts Tertiary amine-modified polyester dispersant 40 parts t-Butyl methacrylate / 2-hydroxyethyl methacrylate / polymethylmethacrylate macromonomer copolymer (monomer composition (parts) = 65/25/15) 20 parts Trimethylolpropane trimethacrylate Over preparative 20 parts of xylene 40 parts of 3-methoxybutyl acetate 840 parts Formulation C Carbon black (average particle size 8 nm, trade name: Statex, Columbian Co.) 40 parts Polyacrylic acid moiety alkyl ester dispersant 40 parts of methacrylic acid t-Butyl / glycidyl methacrylate / polymethylmethacrylate macromonomer copolymer (monomer composition (parts) = 65/25/15) 20 parts methyl 3-methoxypropionate 900 parts Formulation D carbon black (average particle size 8 nm, trade name: Statex, manufactured by Colombian) 40 parts Tertiary amine-modified polyester dispersant 40 parts t-butyl methacrylate / 2-hydroxyethyl methacrylate / polymethylmethacrylate macromonomer copolymer (monomer composition (Part) = 65/25/15) 20 copies Chi trimethylolpropane triglycidyl ether 20 parts Xylene 40 parts 3-methoxybutyl acetate 840 parts Formulation E fullerene C ₆₀ (average particle size 3 nm) 40 parts of tertiary amine-modified polyester dispersant 40 parts of methacrylic acid t- butyl acrylate / glycidyl methacrylate / Polymethylmethacrylate macromonomer copolymer (monomer composition (parts) = 65/25/15) 20 parts Xylene 40 parts 3-methoxybutyl acetate 860 parts Each composition prepared by compounding formulation A-E has a pore size of 2 A composition for forming an antireflection film was prepared by filtering with a 0.5 μm membrane filter, and the formation of the resist pattern and the performance evaluation of the antireflection film were performed as described above. Evaluation results
The results are shown in Tables 1 and 2.

Comparative Examples 1 to 5 In Comparative Examples 1 and 4, no antireflection film was used, and in Comparative Examples 2, 3 and 5, the formulation shown in Table 1 was used, respectively. The resist pattern was formed and the performance of the antireflection film was evaluated in the same manner as in the examples. The evaluation results are shown in Tables 1 and 2.

[0016]

[Table 1]

[0017]

[Table 2]

[0018]

INDUSTRIAL APPLICABILITY The composition for forming an antireflection film of the present invention has excellent storage stability, and the antireflection film formed by using the composition has a high antireflection effect and is excellent in the baking process and the dry etching process. Since it does not sublime and does not cause intermixing with photoresist, it cooperates with positive and negative photoresists to provide a resist pattern with excellent heat resistance, dry etching property, resolution, precision, etc. be able to. Therefore, the composition for forming an antireflection film of the present invention greatly contributes to the production of a highly integrated circuit.

Front page continuation (72) Inventor Akira Tsuji 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. A non-sublimable fine particle having (a) radiation absorption property, (b) a polymer dispersant and (c) an organic solvent, wherein the non-sublimable fine particle is dispersed in an organic solvent. A composition for forming an antireflection film, which is used in the manufacture of an integrated circuit device, comprising: