JPH02273750A - Production of positive type photoresist composition and resist pattern - Google Patents

Abstract

PURPOSE:To obtain the positive type resist compsn. which is suitable for ultrafine working, has a high resolving power and can form good sectional shapes by incorporating an alkaline soluble novolak resin and specific compds. into the compsn. CONSTITUTION:This compsn. contains the alkaline soluble novolak resin and one or >=2 kinds of the compds. expressed by formula I. In the formula, D signifies a hydrogen atom, a naphthoquinone-1, 2-diazide-5-sulfonyl group or naphthoquinone-1, 2-diazide-4-sulfonyl group. D may be the same or different and at least one of D is a naphthoquinone-1, 2-diazide-5-sulfonyl group or naphthoquinone-1, 2-diazide-4-sulfonyl group. The resist compsn. which is adequately used for fine working of semiconductor devices and exhibits the high resolving power and the resist patterns having the excellent sectional shapes are obtd. in this way.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a positive photoresist composition and a method for manufacturing a resist pattern using the same, and is used in the manufacturing process of semiconductor devices such as ICs and LSFs, and has high resolution. The present invention relates to a positive photoresist composition for microfabrication that produces a pattern with a good cross-sectional shape, and a method for producing a resist pattern using the same.

(Prior Art) Positive photoresist compositions currently in use consist of an alkali-soluble novolac resin and a naphthoquinone diazide compound as a photosensitizer.

For example, Japanese Patent Publication No. 37-18015 contains an example containing a novolac resin consisting of talesol-formaldehyde and trihydroxybenzophenone-naphthoquinone-1,2-diazide sulfonic acid ester.

Further, an example of a resist composition using 4-benzyl-1,λ3-trihydroxybenzene naphthoquinone-1,2-diazide sulfonic acid ester as a photosensitizer is described in U.S. Pat. No. 4,737.437. There is.

(Problem to be solved by the invention) The degree of integration of semiconductor devices is increasing year by year.

In the production of VLSIs, patterns with line widths of 1 μm or less are increasingly being designed. Although there is a demand for a photoresist suitable for such microfabrication, conventional positive photoresist compositions are often unable to meet the demand.

An object of the present invention is to provide a positive photoresist composition that is suitable for ultrafine processing, has high resolution, and produces a good cross-sectional shape, and a method for producing a resist pattern using the same.

(Means for Solving Problem 11) The present invention provides an alkali-soluble novolac resin and a compound having the general formula (11 (wherein D is a hydrogen atom, a naphthoquinone-1,2-diazide-5-sulfonyl group, or a naphthoquinone-1゜2 -Diazido-4-sulfonyl group, D may be the same or different, at least one of D is.

A positive photoresist composition containing one or more compounds represented by naphthoquinone-1,2-diazide-5-sulfonyl group or naphthoquinone-1,2-diazide-4-sulfonyl group, and a positive photoresist composition using the same. This invention relates to a method for manufacturing a resist pattern.

The compound of general formula (1) used in the positive-working photoresist composition of the present invention is produced by a condensation reaction of, for example, tetrahydroxydiphenylmethanes represented by general formula (If) and naphthoquinonediazide sulfonyl halides in the presence of a basic catalyst. It can be obtained by letting Condensation reaction: 0-50℃
It is preferable to carry out the reaction at a temperature of 1 to 12 hours.

Examples of the tetrahydroxydiphenylmethanes represented by the general formula (II) include bis(2,3-dihydroxyphenyl)methane, bis(λ4-dihydroxyphenyl)methane, bis(2,5-dihydroxyphenyl)methane, bis( 2,6-dihydroxyphenyl)methane,
Bis(&4-dihydroxyphenyl)methane, bis(λ
5-dihydroxyphenyl)methane, 2,3,24'-
Tetrahydroxydiphenylmethane, z3. '5'
-tetrahydroxydiphenylmethane, λ26'-tetrahydroxydiphenylmethane, zx3:4'-tetrahydroxydiphenylmethane, 2. Denko s'-tetrahydroxydiphenylmethane, z42: s'-tetrahydroxydiphenylmethane, λ4. g 6'-tetrahydroxydiphenylmethane, ZCa<-tetrahydroxydiphenylmethane, z4 5'-tetrahydroxydiphenylmethane, λt e'-tetrahydroxydiphenylmethane, 45.3:4'-tetrahydroxydiphenylmethane, 2. Mr. a: s'-tetrahydroxydiphenylmethane, λ6. Examples include x-tetrahydroxydiphenylmethane, ze, a:s'-tetrahydroxydiphenylmethane, and 4a:s'-tetrahydroxydiphenylmethane.

Moreover, naphthoquinone-1,2-diazide-5-sulfonyl halide and naphthoquinone-1,2-diazide-4-sulfonyl halide can be used as naphthoquinone diazide sulfonyl halides.

Here, the halogen atom of the halide is a chlorine atom.

Examples include bromine atom, iodine atom, and fluorine atom.

As the reaction solvent, solvents such as dioxane, acetone, methyl ethyl ketone, tetrahydrofuran, and N-methylpyrrolidone are used. Basic catalysts include sodium carbonate and sodium hydroxide.

Potassium carbonate, potassium hydroxide, sodium bicarbonate,
Examples include triethylamine, pyridine, and dimethylaminopyridine.

1 to 5 moles, preferably 2 to 4 moles of nyl halides are reacted.

As the compound represented by general formula (1), preferred is (
D has the same meaning as in general formula (1)).

The alkali-soluble novolak resin used in the present invention is a known compound, and is synthesized by condensing phenols and aldehydes before acid-catalyzed subposition. Examples of phenols include phenol, 0-cresol, m-cresol,
p-cresol, 〇-ethylphenol, m-ethylphenol, p-ethylphenol, xylenol, α-
Naphthol, β-naphthol, etc. can be used. Also.

As aldehydes, formaldehyde, paraformaldehyde, acetaldehyde, etc. can be used. Also, examples of acid catalysts include oxalic acid and hydrochloric acid.

Examples include acetic acid and formic acid.

This synthesis can be carried out using, for example, 20 to 80 molar 9m-cresol,
20-80 mol of p-cresol
This is carried out by raising the temperature to 0°C and removing water and unreacted monomers.

The compounding ratio of the alkali-soluble novolac resin and the compound represented by the above general formula (11) in the present invention is 10 to 100 parts by weight, preferably 15 to 40 parts by weight of the photosensitizer per 100 parts by weight of the alkali-soluble novolak resin. is.

The positive photoresist composition of the present invention is dissolved in a solvent to obtain a resist composition. Ethyl cellosolve acetate, methyl Cellosolve acetate, methyl ethyl ketone, cyclohexanone, ethyl acetate, butyl acetate, and the like can be used.

A dye, a surfactant, etc. can be added to the positive photoresist composition of the present invention, if necessary.

The positive photoresist composition is coated on a silicon substrate or the like using a coater or the like using a known method and dried.

A good resist pattern can be obtained by exposing and developing using a reduction projection exposure device or the like.

The developer used in the present invention includes sodium hydroxide, potassium hydroxide, and sodium silicate.

Examples include ammonia, ethylamine, diethylamine, triethylamine, triethanolamine, and tetramethylammonium hydroxide. Furthermore, an appropriate amount of alcohol or surfactant may be added to the developer.

(Example) The present invention will be described in detail.

(1) Synthesis Example 1 of Photosensitizer 7189 parts by weight of bis(2,4-dihydroxyphenyl)meta and 36-0 parts by weight of naphthoquinone-1,2-diazide-5-sulfonyl chloride [(a5-e ratio)] A mixed solution of 13.7 parts by weight of triethylamine and 750.0 parts by weight of dioxa was gradually added dropwise to 200 parts by weight while stirring, and the mixture was allowed to react for 4 hours. After the reaction is complete,
The contents were dropped into a 1% aqueous hydrochloric acid solution, and the resulting precipitate was
Separately, wash with water.

After washing with methanol and drying, a photosensitizer 1 was obtained.

(2) Photosensitizer Synthesis Example 2 Photosensitizers 2 to 11 were synthesized in the same manner as Photosensitizer Synthesis Example 1 under the synthesis conditions shown in Table 1.

(3) Synthesis Example of Photosensitizer (Comparative Example) 12,134 To 1 mole of 4-trihydroxybenzophenone or λ3,4,4'-tetrahydroxybenzophenone, naphthoquinone-1,2-diazide-5-sulfonyl chloride was added. 47
mol (Comparative Example 1) or a5 mol (Comparative Example 2) were prepared, and photosensitizers 12.13 were synthesized in the same manner as in Synthesis Example 1 of Photosensitizers.

(4) Synthesis example of alkali-soluble novolak resin 1 58.5 parts by weight of m-cresol, 69.5 parts by weight of p-cresol, 68.4 parts by weight of 37% formalin aqueous solution and 0.51 parts by weight of oxalic acid were charged into a reaction vessel. After that, the reaction temperature was raised to 100°C while stirring.

The reaction was allowed to proceed for 5 hours. After the reaction, the temperature was raised to 170°C.

Make sure to remove water and unreacted monomers under reduced pressure. After cooling to room temperature, alkali-soluble novolak resin 1 was obtained.

(5) Synthesis Example 2 of Alkali-Soluble Novolak Resin 64.2 parts by weight of m-cresol, 67.9 parts by weight of p-cresol, 78.5 parts by weight of 37 thiformin aqueous solution and 90.64 parts by weight of Shu were charged into a reaction vessel. After that, the reaction temperature was raised to 120° C. with stirring, and the reaction was continued for 6 hours. After reaction 1
The temperature was raised to 70°C, and water and unreacted monomers were removed under reduced pressure. After cooling to room temperature, alkali-soluble novolak resin 2 was obtained.

Examples 1-11. Comparative example 1. 2 Dissolve 5 parts by weight of each of photosensitizers 1 to 11 obtained in the above synthesis examples and photosensitizer 12.13 obtained in comparative examples, 25 parts by weight of alkali-soluble novolak resin 1 or 2, and 71 parts by weight of ethyl cellosolve acetate. .

A resist solution was prepared. This resist solution was filtered using a 0.2 μm Teflon filter to prepare a resist composition. This was spin-coated onto a silicon wafer and baked on a hot plate at 80° C. for 50 seconds to obtain a 1.22 μm resist film. After that, using a G-line or L-line reduction projection exposure device (Canon G-line stepper FPA-1550, Hitachi AT-line stepper LD-50101),
00 off 00 mJ/am" exposure was carried out. Development was carried out for 1 minute using a Z38-th tetramethylammonium hydroxide aqueous solution, washed with water and dried. The resist pattern on the silicon wafer thus obtained was It was observed and evaluated using a scanning electron microscope.

The results are shown in Table 2. The resolution represents the minimum pattern size that can be resolved as lines and spaces according to the pattern dimensions at an exposure dose that reproduces a mask pattern with a line width of 1.0 μm. The resist shape has a line width of 1.0μ
It is expressed as the angle (θ) between the resist wall surface and the silicon wafer in the resist pattern cross section of m.

As is clear from Table 2, high resolution and good resist pattern shape can be obtained with the positive photoresist composition of the present invention.

(Effects of the Invention) The positive photoresist composition of the present invention is suitably used for microfabrication in the manufacture of semiconductor devices and exhibits high resolution, thereby making it possible to obtain resist patterns with excellent cross-sectional shapes.

Claims (1)

[Claims] 1. Alkali-soluble novolak resin and general formula (I
) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (D in the formula means a hydrogen atom, a naphthoquinone-1,2-diazide-5-sulfonyl group, or a naphthoquinone-1,2-diazide-4-sulfonyl group D.
may be the same or different, and at least one of D is a naphthoquinone-1,2-diazido-5-sulfonyl group or a naphthoquinone-1,2-diazido-4-sulfonyl group) Or a positive photoresist composition containing two or more types. 2. A positive photoresist composition in claim 1, wherein the compound represented by the general formula (I) is ▲a mathematical formula, a chemical formula, a table, etc.▼. 3. A positive photoresist composition in which the compound represented by the general formula (I) in the claims is ▲a mathematical formula, a chemical formula, a table, etc.▼. 4. A method for producing a resist pattern, which comprises applying the positive photoresist composition according to claim 1 onto a substrate, exposing it to light, and developing it.