JPS6120030A - Resist composition - Google Patents

Abstract

PURPOSE:To impart sufficient photosensitivity and resolution as a photoresist by forming a resist compsn. consisting of a silicone resin having high glass transition point and a bisazo compd. having high photoreactivity. CONSTITUTION:The silicone resin of silsesquioxane polymer represented by formula I is prepared by substituting the chloro group of chloromethylphenylalkylsilsesquioxane polymer obtained by hydrolyzing a silane compd. The bisamide compd. is at least one kind selected from compds. represented by formula IIin which R1 is a simple bond, -CH2-, or -O-, and R2 is H or halogen. Further, a sensitizer selected from aromatic carbonyl compds. is used. The use of combination of the silicone polymer having high glass transition point and the bisazide compd. having high photoreactivity imparts sufficient photosensitivity and resolution and permits swelling phenomenon in development to be suppressed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to semiconductor devices, magnetic bubble devices, optical application parts, etc. ! The present invention relates to a resist composition that can be used for fabrication.

[Conventional technology]

Conventionally, in the production of ICs and LSIs, etc., a wrinkled substrate is nuclided with an organic composition such as a polymer compound called resist, and a resist KWI image is formed by irradiating it with high-energy rays in a pattern, which is then developed. After forming a patterned resist film, the substrate to be processed is immersed in a corrosive solution to chemically etch the portions of the substrate not covered by the resist or to dope with impurities.

However, in recent years, as integrated circuits have become more highly integrated, it has become desirable to form even finer patterns.In order to meet this demand, even more resist methods have been proposed. For the upper layer of the resist, a silicone resist having excellent oxygen plasma resistance is used.

[Problem that the invention attempts to solve]

However, currently known silicone resists have glass transition temperatures considerably lower than room temperature, and polymers with low molecular weights are liquid or semi-liquid, making them extremely difficult to handle and sensitive to light.

On the other hand, when the molecular weight is increased, it becomes rubber-like, becomes slightly easier to handle, and has higher sensitivity, but it also has disadvantages such as swelling in the developing solvent, which causes ridges in the pattern and a decrease in resolution. Ta.

[Means to solve the problem]

The resist composition of the present invention has the following general formula (11% formula %) (wherein X is -0-C-C=CH2, -0-C-CH=
CH2 represents a group, m and n represent positive integers. ) contains a silsesquioxane polymer represented by the formula, a bisacide compound, and a sensitizer. -1-C
H=CH-1-N=N-1-8-1↑ Ha, and one or more selected from the group consisting of compounds represented by (R2 is a hydrogen atom or a halogen atom) is used. Furthermore, as the above-mentioned sensitizers, aromatic carbonyl compounds, benzoin compounds, dye redox compounds, azo compounds, sulfur-containing compounds, organic peroxides, aromatic nitro compounds, quinone compounds, anthrone compounds, and acenaphthene compounds can be used. A type selected from the following group is used.

Specific examples of the bisazide compound include 3,3'-dichloro-4,4'-diacitodiphenylmethane, 4,4'-diazidiphenyl ether,
．． Examples include 4'-diazidiphenylmethane, 4,4'-diazidiphenylsulfone, 3°3'-diazidiphenylsulfone, and 4,4'-diazidiphenylketone. The amount of these added is preferably from at to 30 times the phenylsilsesquioxane polymer of formula I above. If the aS content is less than 30% by weight, no crosslinking will occur, and if it exceeds 30% by weight, the long-term storage stability and coating properties will deteriorate.

Moreover, as the above-mentioned sensitizer, those used in conventional photoresists can be used. For example, benzoin-based compounds such as benzoin methyl ether, azo compounds such as azobisisobutyronitrile, dye redox compounds that are a combination of dyes such as chlorophyll, methylene blue, eosin Y, and a simulating agent such as p-) sodium luenesulfinate;
Sulfur-containing compounds such as dibenzothiazoyl disulfide, organic peroxides such as benzoyl peroxide, aromatic carbonyl compounds such as benzophenone and Michler's ketone, aromatic nitro compounds such as nitrobenzene, P-nitrophenol, P-nitroaniline, and nitropyrene, Examples include quinone compounds such as anthraquinone, acenaphthene compounds such as 5-nitroacenaphthene, and anthrone compounds. The amount of these additives to be added is approximately aj to IO% by weight based on the polymer of formula (I).

The chloro group of the chloromethylphenylalkylsilsesquioxane polymer easily obtained by hydrolyzing the silsesquioxane silane compound represented by the general formula (I) of the present invention is -0-C-C=CH2, - 〇-C-
There is a method of substituting with a group such as CfI=CH2°.

[Effect]

The resist composition of the present invention combines a silicone polymer with a high glass transition temperature (Tg) and a bisazide compound with high photoreactivity, so it has sufficient photosensitivity and understanding as a photoresist. It has imageability and suppresses swelling phenomenon during development. It also has excellent oxygen plasma resistance and can form patterns with a high shape ratio. The most important point here is that the above resist composition is highly sensitive to light, and is free from oxygen gas, carbon tetrachloride,
It has been discovered that the material exhibits high resistance to etchant gases used in reactive ion etching such as CF2Cl2.

[Manufacturing example]

An example of manufacturing a silsesquioxane polymer, which is a component of the resist composition in the present invention, will be shown below.

Production Example 1 After decomposing chloromethylphenyltrichlorosilylethano 01 with N-methylpyrrolidone jOtxlVUla,
20 ml of H2O was added and the mixture was left at 30°C for 24°C. After washing the precipitate with water, it was dissolved in tetrahydrofuran-○- and poured into methanol to obtain a white polymer. The obtained chloromethylphenylethylsilsesquioxane polymer 6y was dissolved in dimethylformamide 7odVcfa, potassium methacrylate 6V and trimethylethylammonium iodide aP2 were added, and the mixture was stirred at 30°C for 5 hours.

The reaction solution was poured into methanol to obtain methacryloyloxymethylphenylethylsilsesquioxane polymer.

Production Examples 2 and 3 Acryloyloxymethylphenylethyl silsesquioxane polymer (Preparation Example 2) was prepared using potassium acrylate in place of potassium methacrylate in Production Example 1, and cinnamoyloxymethylphenyl was prepared using potassium cinnamate. Ethylsilsesquioxane polymer (Production Example 3) was obtained.

〔Example〕

Next, the present invention will be explained in detail with reference to Examples, but the present invention is not limited thereto.

Example 1 Polymer Jr obtained in Production Example 1 was added to 70 ml of chlorobenzene.
To this were added 3,3'-dichloro-4'4'-diazidiphenylmethane zooytpg and 30 ml of Michler's ketone as a sensitizer. Next, the quartz plate <ye
It was spread to a thickness of arμm and prebaked at to°C for 20 minutes in a nitrogen stream. After prebaking, it was irradiated using an ultra-high pressure mercury lamp in a nitrogen atmosphere using a Kodak Photographic Step Tablet as a mask. After irradiation, the quartz plate was developed with methyl ethyl ketone for 20 seconds, and then with isopropyl alcohol for 6 seconds.
Rinsed for 0 seconds. At this time, the amount of light irradiation remaining at jO% of the initial film thickness is Noah mJ/cd, which is a sensitivity that can be used practically. (9) After irradiating light through a chrome masker with a line-and-space pattern of 70 μm or less, development was performed with a developer having the same composition as above, and the mask pattern could be faithfully resolved.

Examples 2 and 3 In Example 1, the polymers obtained in Production Examples 2 and 3 were used instead of the polymer obtained in Production Example 1, and the same irradiation and development as in Example 1 were performed. At this time, the initial film thickness roqb and the remaining light irradiation amount are /OmJ/crl and KoOmJ/, respectively.
I went to di. Furthermore, when the film was developed by irradiating light through a chrome mask having a line-and-space pattern of □ μm or less, the pattern of the mask could be faithfully resolved.

Examples 4 to 11 4.4'-diazidiphenyl ether (Example 4), 4,4'-diazidiphenyl sulfone in place of 3.3'-dichloro-4,4'-diazidiphenylmethane in Example I (Example 5), 4.

4'~Diazidiphenylmethane (Example 6), 3°3
7-Diazidodiphenylsulfone (Example 7), 3.3
'-Diazidiphenylmethane (Example 8), 4.4'
-Diazidodibenzalacetone (Example 9), 2.6-
Di(4'-azidobenzal)cyclohexanone (Example 10), 2,6-di(4'-azidobenzal)-4-
Using methylcyclohexanone (Example 11), jkW
The film was developed after being irradiated with an ultra-high pressure mercury lamp. At this time, Table 1 shows the amount of light irradiation that leaves 60% of the initial film thickness.

Table 1 Examples 12 to 18 and Comparative Example 1 Polymer 2 obtained in Production Example 1 was added to chlorobenzene Oxl.
and 2,6-di(4'-azidobenzal)-4-methylcyclohexanone jt00■ and 5-nitroacenaphthene (Example 12), 2-nitrofluorene (Example 13) as sensitizers. 1-nitropyrene (Example 14), 1,8-dinitropyrene (actual m% Jt 5
), 1,2-benzaanthraquinone (Example 16),
JO1q of pyrene-1,6-quinone (Example 17) and cyanoacridine (Example 18) were each added. A sample without any sensitizer added was also prepared. (Comparative Example 1) These were coated, irradiated with light, and developed by the method of Example 1. Table 2 shows the amount of light irradiation that remained after the initial film thickness of J'O.

Table 2 Examples 19 to 23 Patterns obtained in the same manner as in Example 1 were used for CF4 (Example 19), CF2CLz (Example 20), CCL< (Example 21), 02 (Example 22), and Ar (Example 22). Example 23)
Reactive ion etching was performed using each gas as an etchant gas. Table 3 shows the etching conditions and the etching rate of the resist composition at this time.

Table 3 [Effects of the Invention] As explained above, the resist composition of the present invention is composed of a silicone resin having a high glass transition temperature and a bisazide compound exhibiting high photoreactivity, and therefore has sufficient photosensitivity as a photoresist. It has high resolution. In particular, the high glass transition temperature of the silicone resin suppresses swelling during development, which has been a problem in the past, and the resolution is significantly improved.

Furthermore, since it has excellent oxygen plasma resistance, if it is used as an upper layer of a two-layer resist having a thick organic polymer as the lower layer, the portion covered with the resist composition will hardly be etched. Therefore, a pattern with a high shape ratio can be formed.

As described above, when the resist composition of the present invention is used, K
Since it is possible to form a thick and fine pattern, it is very useful when forming a pattern with a step difference or performing high-acceleration ion implantation.

Claims (3)

[Claims] (1) General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (X in the formula is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Yes, 1 selected from ▼
It represents a species group, and m and n represent positive integers. ) A resist composition comprising a silsesquioxane polymer represented by the following formula, a bisazide compound, and a sensitizer. (2) The above bisazide compound has the following general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, R_1 is a direct bond, or -CH_2-, -O-,
1CH=CH-, -N=N-, -S-, ▲Mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas,
There are tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼
, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , R_2 is a hydrogen atom or a halogen atom) The resist composition according to claim 1, which is one or more kinds of resist compositions. (3) The sensitizer is an aromatic carbonyl compound, a benzoin compound, a dye redox compound, an azo compound,
3. The resist composition according to claim 2, which is one selected from the group consisting of sulfur-containing compounds, organic peroxides, aromatic nitro compounds, quinone compounds, anthrone compounds, and acenaphthene compounds.