JPH04274431A - Positive type photoresist composition - Google Patents

Abstract

PURPOSE:To improve a resolving power, faithful reproducibility and heat resistance and to expand development latitude as well as to allow the formation of resist patterns having sectional shapes of a high aspect ratio by incorporating specific photosensitive materials and alkaline-soluble resin. CONSTITUTION:This compsn. contains at least one kind of the photosensitive materials expressed by formula I and the alkaline-soluble resin. In the formula I, R denotes a hydrogen atom, etc.; at least one of three Rs is exclusive of the hydrogen atom; X denotes -S-, etc.; Y denotes a hydrogen atom, 1 to 4C alkyl group, etc. The novolak resin as the alkaline-soluble resin is obtd. by bringing 0.6 to 1.0mol aldehydes into addition condensation with 1mol phenols in the presence of an acid catalyst. The ratio of using the photosensitive materials and the alkaline-soluble novolak resin is 5 to 100 pts.wt., more preferably 10 to 50 pts.wt. photosensitive material per 100 pts.wt. novolak resin.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a positive photoresist composition that is sensitive to radiation, and in particular to a photoresist composition for microfabrication that has high resolution and sensitivity, as well as a good pattern cross-sectional shape. It is something. The positive photoresist according to the present invention can be applied to semiconductor wafers,
It is applied to a thickness of 0.5 to 3 μm onto a substrate such as glass, ceramics, or metal by spin coating or roller coating. Thereafter, it is heated and dried, and a circuit pattern and the like are printed by irradiation with ultraviolet rays through an exposure mask and developed to form a positive image. Further, by etching this positive image as a mask, a pattern can be processed on the substrate. Typical application fields include IC
There are semiconductor manufacturing processes such as, manufacturing of circuit boards such as liquid crystals and thermal heads, and other photoablation processes.

0002

[Prior Art] As a positive photoresist composition,
Generally, a composition containing an alkali-soluble resin and a naphthoquinone diazide compound as a photosensitive material is used. For example, USP-3,666,473 as "Novolak type phenolic resin/naphthoquinone diazide substituted compound"
No., USP-4,115,128 and USP-4,1
No. 73,470, etc., and as the most typical composition.
An example of ``Novolac resin consisting of cresol-formaldehyde/trihydroxybenzophenone-1,2 naphthoquinone diazide sulfonic acid ester'' is given by L.F. Thompson ``Introduction to Microlithography''.
duction to Microlitho-g
(ACS Publishing, No. 219, P1
12-121). Novolac resins as binders are particularly useful in this application because they can be dissolved in aqueous alkaline solutions without swelling and also provide high resistance to plasma etching, especially when the resulting image is used as an etching mask. It is. In addition, the naphthoquinonediazide compound used in photosensitive materials itself acts as a dissolution inhibitor that reduces the alkali solubility of novolak resin, but when it decomposes upon exposure to light, it produces alkali-soluble substances and rather reduces the alkali solubility of novolak resin. It is unique in that it acts as a light enhancer, and because of its large change in properties with respect to light, it is particularly useful as a photosensitive material for positive photoresists. From this point of view, many positive photoresists containing novolac resins and naphthoquinone diazide photoresists have been developed and put into practical use, and have achieved satisfactory results in line width processing of approximately 1.5 μm to 2 μm. .

However, the degree of integration of integrated circuits is increasing more and more, and in the production of semiconductor substrates such as VLSIs, 1
It has become necessary to process ultra-fine patterns having line widths of μm or less. In such applications, a photoresist is required that has particularly high resolution, high pattern shape reproduction accuracy to accurately copy the shape of the exposure mask, and high sensitivity from the viewpoint of high productivity, which the conventional positive photoresists mentioned above cannot meet. The reality is that it is not possible.

0004

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to solve the following problems, especially in the production of semiconductor devices:
Positive photoresist composition with high resolution,
(2) a positive photoresist composition that accurately reproduces mask dimensions over a wide range of photomask line widths;
(3) A positive photoresist composition capable of producing a cross-sectional resist pattern with a high aspect ratio in a pattern with a line width of 1 μm or less; (4) A positive photoresist composition capable of producing a cross-sectional resist pattern with a nearly vertical sidewall in the cross-section of the pattern; (5) A positive photoresist composition having a wide development latitude, (6)
) An object of the present invention is to provide a positive type photoresist composition whose resulting resist image has excellent heat resistance.

[0005]

[Means for Solving the Problems] As a result of careful consideration and consideration of the above-mentioned characteristics, the present inventors have found that the object of the present invention is to provide at least one photosensitive material represented by the following general formula (I) and an alkali-soluble resin. It has been found that this can be achieved by a positive photoresist composition characterized by containing.

[0006]

[Chemical formula 3]

[0007]Here,

[0008]

[C4]

The present invention will be explained in detail below. R is H
or

0010

[C5]

represents one or more substituents selected from the following, and at least one is not H.

The linking group X is -S-, -O-, -SO-, -
SO2-, -SO3-, -SO2NH-, -N=N-,
-NH-, -NHNH-, or

[0013]

[C6]

0014 is represented. Among these, preferred are -S-, -O-, -SO2-, -SO3-, -SO2N
H-, or

[0015]

[C7]

[0016] Here, R1, R
2: H, an alkyl group, an aryl group, an aralkyl group, or a cyano group, provided that when one is H or an alkyl group, the other is an aryl group, an aralkyl group, or a cyano group,
R3, R4: H, represents an alkyl group, an aryl group, an aralkyl group, or R5-O-CH2- (R5 is an alkyl group or an aryl group). Although R1 and R2 represent the above-mentioned groups, a preferred embodiment is when one is H or an alkyl group and the other is an aryl group, an aralkyl group, or a cyano group. R3 and R4 represent the above-mentioned groups, preferably H, a C1-C4 alkyl group, a C6-C10 aryl group or an aralkyl group. A preferred embodiment of R5 is a C1-C4 alkyl group or a C6-C10 aryl group. Y represents the above-mentioned group, preferably H,
C1-C4 alkyl group, alkoxy group, C6-C10
, an aryl group or an aralkyl group, a halogen such as Cl or Br, and a -NO2 group.

The photosensitive material represented by the general formula (I) is a polyhydroxy compound represented by the following general formula (I') containing 1,
2-Naphthoquinonediazide-5 (and/or -4)-
Obtained by reacting sulfonyl chloride.

[0018]

[Chemical formula 8]

[0019] A polyhydroxy compound represented by the general formula (I') and 1,2-naphthoquinone diazide-5 (and/
Or -4) A conventional method can be used for the esterification reaction with -sulfonyl chloride. That is, a predetermined amount of the polyhydroxy compound represented by (I'), 1,2-naphthoquinonediazide-5 (and/or -4)-sulfonyl chloride, dioxane, acetone, γ-butyrolactone,
A solvent such as methyl ethyl ketone or N-methylpyrrolidone is charged into a flask, and a basic catalyst such as sodium hydroxide, sodium carbonate, sodium hydrogen carbonate, triethylamine, etc. is added dropwise to cause condensation. The obtained product is
After washing with water, purify and dry. In this way, general formula (I)
A photosensitive material represented by can be prepared.

In the above esterification reaction, mixtures having various esterification numbers and esterification positions are obtained. Therefore, the esterification rate in the present invention is defined as the average value of this mixture. The esterification rate defined in this way can be controlled by the mixing ratio of compound (I') as a raw material and 1,2-naphthoquinonediazide-5 (and/or -4)-sulfonyl chloride. That is, since substantially all of the added 1,2-naphthoquinonediazide-5 (and/or -4)-sulfonyl chloride causes an esterification reaction, in order to obtain a mixture with the desired esterification rate, it is necessary to Just adjust the molar ratio. If necessary, 1,2-naphthoquinonediazide-5-sulfonic acid ester and 1,2-naphthoquinonediazide-4-sulfonic acid ester can also be used together. Further, the reaction temperature in the above method is usually -20 to 60°C, preferably 0.
~40°C.

The alkali-soluble novolak resin used in the present invention contains 0.6 aldehydes per mole of phenols.
It is obtained by addition condensation of ~1.0 mol under acidic catalyst. As the phenols, phenol, o-cresol, m-cresol, p-cresol, etc. can be used alone or in combination of two or more. Further, as the aldehyde, formaldehyde, paraformaldehyde, acetaldehyde, halogenated acetaldehyde (for example, chloro, bromo), or furfural can be used, and as the acidic catalyst, hydrochloric acid, sulfuric acid, formic acid, oxalic acid, acetic acid, etc. can be used. The molecular weight thus obtained was 10
Novolac resins with a rating of 00 to 50,000 exhibit alkali solubility. The ratio of the photosensitive material and the alkali-soluble novolak resin used in the present invention is 5 to 100 parts by weight, preferably 10 to 50 parts by weight, per 100 parts by weight of the novolak resin. If this usage ratio is less than 5 parts by weight, the residual film rate will be significantly reduced, and if it exceeds 100 parts by weight, sensitivity and solubility in solvents will be reduced.

In the present invention, the above-mentioned photosensitive material should be mainly used, but if necessary, ordinary photosensitive materials such as 2,
3,4-trihydroxybenzophenone, 2,4,4'
An esterified product of -trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone, etc. and 1,2-naphthoquinonediazide-5-(and/or -4-)sulfonyl chloride can be used in combination. In this case, it can be used in an amount of 100 parts by weight or less, preferably 30 parts by weight or less, per 100 parts by weight of the photosensitive material (I).

The composition of the present invention may further contain other polyhydroxy compounds in order to promote dissolution in the developer. Preferred polyhydroxy compounds include:
Phenols, resorcinol, phloroglucinum, 2,3,
4-trihydroxybenzophenone, 2,3,4,4'
-tetrahydroxybenzophenone, 2,3,4,3'
, 4',5'-hexahydroxybenzophenone, acetone-pyrogallol condensation resin and the like.

Examples of the solvent for dissolving the photosensitive material and the alkali-soluble novolac resin of the present invention include ketones such as methyl ethyl ketone and cyclohexanone, and 4-ethoxy-2
- Keto ethers such as butanone and 4-methoxy-4-methyl-2-pentanone, alcohol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, ethers such as dioxane and ethylene glycol dimethyl ether, methyl cellosolve acetate, ethyl Cellosolve esters such as cellosolve acetate, fatty acid esters such as butyl acetate, methyl lactate, ethyl lactate, halogenated hydrocarbons such as 1,1,2-trichloroethylene, dimethylacetamide, N
- Highly polar solvents such as methylpyrrolidone, dimethylformamide, and dimethylsulfoxide can be exemplified. These solvents can be used alone or in combination.

The positive photoresist composition of the present invention may contain dyes, plasticizers, adhesion aids, surfactants, and the like, if necessary. Specific examples include dyes such as methyl violet, crystal violet, and malachite green, stearic acid, plasticizers such as acetal resin, phenoxy resin, and alkyd resin, adhesive aids such as hexamethyldisilazane and chloromethylsilane, and nonyl. There are surfactants such as phenoxypoly(ethyleneoxy)ethanol and octylphenoxypoly(ethyleneoxy)ethanol.

The above composition for positive photoresist is coated onto a substrate (eg silicon/silicon dioxide coated) such as that used in the manufacture of precision integrated circuit elements using an appropriate coating method such as a spinner or coater, and then coated in a predetermined manner. A good resist can be obtained by exposing the resist to light through a mask and developing it. The developing solution for the positive photoresist composition of the present invention includes sodium hydroxide, potassium hydroxide,
Inorganic alkalis such as sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, triethylamine, and methyldiethylamine. tertiary amines such as dimethylethanolamine, alcohol amines such as triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide, cyclic amines such as pyrrole and piperidine, alkalis such as Aqueous solutions of the following types can be used. Furthermore, appropriate amounts of alcohols and surfactants may be added to the aqueous alkali solution. below,
Examples of the present invention will be shown, but the present invention is not limited thereto. Note that % indicates weight % unless otherwise specified.

[0027]

[Example] (1) Synthesis of photosensitive material a 10 g of the following compound (a'),

[0028]

[Chemical formula 9]

28.7 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 300 ml of acetone were
The mixture was poured into a neck flask and dissolved uniformly. Next, triethylamine/acetone=11.3 g/40 ml was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. 1% reaction mixture
It was poured into 1,600 ml of an aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material a having the physical properties shown in Table 1.

(2) Synthesis of photosensitive material b 10 g of the following compound (b'),

[0031]

[Chemical formula 10]

24.7 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 260 ml of acetone were
The mixture was poured into a neck flask and dissolved uniformly. Next, triethylamine/acetone=9.8 g/35 ml was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. The reaction mixture was poured into 1400 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain photosensitive material b having the physical properties shown in Table 1.

(3) Synthesis of photosensitive material c 10 g of the following compound (c'),

[0034]

[Chemical formula 11]

27.3 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 300 ml of acetone were
The mixture was poured into a neck flask and dissolved uniformly. Next, triethylamine/acetone=10.6 g/38 ml was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. 1% reaction mixture
The mixture was poured into 1,600 ml of an aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material c having the physical properties shown in Table 1.

(4) Synthesis of photosensitive material d 10 g of the following compound (d'),

[0037]

[Chemical formula 12]

21.0 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 230 ml of acetone were
The mixture was poured into a neck flask and dissolved uniformly. Next, triethylamine/acetone=8.3 g/30 ml was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. The reaction mixture was poured into 1200 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material d having the physical properties shown in Table 1.

(5) Synthesis of photosensitive material e 10 g of the following compound (e'),

[0040]

[Chemical formula 13]

15.5 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 17 g of γ-butyllactone
0 ml was placed in a three-necked flask and uniformly dissolved. Then, triethylamine/acetone = 6.1g/22ml
was gradually added dropwise, and the mixture was reacted at 25°C for 3 hours. The reaction mixture was poured into 900 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material e having the physical properties shown in Table 1.

(6) Synthesis of photosensitive material f 10 g of the following compound (f'),

[0043]

[Chemical formula 14]

18.6 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 20 g of γ-butyllactone
0 ml was placed in a three-necked flask and uniformly dissolved. Then, triethylamine/acetone = 7.4g/27ml
was gradually added dropwise, and the mixture was reacted at 25°C for 3 hours. The reaction mixture was poured into 1100 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material f having the physical properties shown in Table 1.

(7) Synthesis of photosensitive material g 10 g of the following compound (g'),

[0046]

[Chemical formula 15]

28.7 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 30 g of γ-butyllactone
0 ml was placed in a three-necked flask and uniformly dissolved. Then, triethylamine/acetone=11.3g/40m
1 was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. The reaction mixture was poured into 1700 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain photosensitive material g having the physical properties shown in Table 1.

(8) Synthesis of photosensitive material h 10 g of the following compound (h'),

[0049]

[Chemical formula 16]

25.1 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 260 ml of acetone were
The mixture was poured into a neck flask and dissolved uniformly. Next, triethylamine/acetone=9.7 g/35 ml was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. The reaction mixture was poured into 1500 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material h having the physical properties shown in Table 1.

(9) Synthesis of photosensitive material i 10 g of the following compound (i'),

[0052]

[Chemical formula 17]

31.5 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 330 ml of acetone were
The mixture was poured into a neck flask and dissolved uniformly. Next, triethylamine/acetone=12.2 g/45 ml was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. 1% reaction mixture
It was poured into 1900 ml of an aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material i having the physical properties shown in Table 1.

(10) Synthesis of photosensitive material j 10 g of the following compound (j'),

[0055]

[Chemical formula 18]

20.1 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 210 ml of acetone were
The mixture was poured into a neck flask and dissolved uniformly. Next, triethylamine/acetone=7.8 g/30 ml was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. The reaction mixture was poured into 1200 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material j having the physical properties shown in Table 1.

(11) Synthesis of photosensitive material k 10 g of the following compound (k'),

[0058]

[Chemical formula 19]

37.1 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 40 g of γ-butyllactone
0 ml was placed in a three-necked flask and uniformly dissolved. Then, triethylamine/acetone = 14.7g/60m
1 was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. The reaction mixture was poured into 2200 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain photosensitive material k having the physical properties shown in Table 1.

(12) Synthesis of photosensitive material l 10 g of the following compound (l'),

[0061]

[C20]

18.4 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 20 g of γ-butyllactone
0 ml was placed in a three-necked flask and uniformly dissolved. Then, triethylamine/acetone = 7.3g/30ml
was gradually added dropwise, and the mixture was reacted at 25°C for 3 hours. The reaction mixture was poured into 1,100 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain photosensitive material 1 having the physical properties shown in Table 1.

(13) Synthesis of photosensitive material m 10 g of the following compound (m'),

[0064]

[C21]

18.4 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 20 g of γ-butyllactone
0 ml was placed in a three-necked flask and uniformly dissolved. Then, triethylamine/acetone = 7.3g/30ml
was gradually added dropwise, and the mixture was reacted at 25°C for 3 hours. The reaction mixture was poured into 1100 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain photosensitive material m having the physical properties shown in Table 1.

(14) Synthesis of photosensitive material n 10 g of the following compound (n'),

[0067]

[C22]

21.5 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 25 g of γ-butyllactone
0 ml was placed in a three-necked flask and uniformly dissolved. Then, triethylamine/acetone = 8.5g/35ml
was gradually added dropwise, and the mixture was reacted at 25°C for 3 hours. The reaction mixture was poured into 1300 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material n having the physical properties shown in Table 1.

(15) Synthesis of photosensitive material o 10 g of the following compound (o'),

[0070]

[C23]

20.9 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 25 g of γ-butyllactone
0 ml was placed in a three-necked flask and uniformly dissolved. Then, triethylamine/acetone = 8.0g/33ml
was gradually added dropwise, and the mixture was reacted at 25°C for 3 hours. The reaction mixture was poured into 1300 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material o having the physical properties shown in Table 1.

(16) Synthesis of photosensitive material p (Comparative Example 1) 10 g of the following compound (p'),

[0073]

[C24]

30.0 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 340 ml of acetone were
The mixture was poured into a neck flask and dissolved uniformly. Next, triethylamine/acetone=11.9 g/50 ml was gradually added dropwise, and the mixture was reacted at 25° C. for 3 hours. 1% reaction mixture
It was poured into 2000 ml of an aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material p having the physical properties shown in Table 1.

(17) Synthesis of photosensitive material q (Comparative Example 2) 10 g of the above compound (p'), 41.5 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride, and 470 ml of γ-butyl lactone were placed in a three-necked flask. It was prepared and dissolved uniformly. Then, triethylamine/acetone = 16.4
g/70ml was gradually added dropwise, and the mixture was reacted at 25°C for 3 hours. The reaction mixture was poured into 2700 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was filtered off, washed with water and dried (40°C) to obtain a photosensitive material q having the physical properties shown in Table 1.

[0076]

[Table 1]

(18) Synthesis of novolak resin 37 g of m-cresol, 63 g of p-cresol, 51.0 g of 37% formalin aqueous solution and 0.05 g of oxalic acid were placed in a three-necked flask, and the temperature was raised to 100°C while stirring. The reaction was allowed to proceed for 7 hours. After the reaction, the reaction 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 obtained novolak resin had a weight average molecular weight of 7,500 (in terms of polystyrene).

(19) Preparation and evaluation of positive photoresist composition Photosensitive materials a to q obtained in the above (1) to (17) 1.1 each
0 g and 5 g of the cresol novolac resin (molecular weight 7500) obtained in (18) above were dissolved in 18 g of ethyl cellosolve acetate, filtered using a 0.2 μm microfilter, and photoresist (Examples 1 to 15, Comparative) Examples 1 and 2) were prepared. This photoresist composition was applied to a silicon wafer using a spinner and dried at 110°C for 30 minutes in a convection oven under a nitrogen atmosphere to a film thickness of 1.
．． A 2 μm resist film was obtained. This film was exposed using a reduction projection exposure device (NSR1505, manufactured by Nikon Corporation), developed with a 2.38% aqueous tetramethylammonium hydroxide solution for 1 minute, washed with water for 30 seconds, and dried. The resist pattern of the silicon wafer thus obtained was observed with a scanning electron microscope and the resist was evaluated. The results are shown in Table 2. The sensitivity was defined as the reciprocal of the exposure amount for reproducing a 1.0 μm mask pattern, and was expressed as a relative value to the sensitivity of Comparative Example 2. The residual film rate was expressed as a percentage of the ratio of the unexposed area before and after development. The resolution is 1.
It represents the limit resolution at an exposure dose that reproduces a 0 μm mask pattern. Heat resistance was determined by baking a silicon wafer on which a resist pattern was formed for 30 minutes in a convection oven, and showing the temperature at which the pattern did not deform. The shape of the resist is determined by the angle (
Θ). As will be seen, the photosensitive materials of the present invention a~
o The resist used had particularly excellent resolution and resist shape. The photosensitive materials of the present invention also have excellent solubility in ethylene glycol monoethyl ether acetate, and resist composition solutions using these photosensitive materials have a 40%
Although no precipitate was deposited even after being left at ℃ for 30 days,
When resist composition solutions using photoreceptors p and q of comparative examples were left to stand under the same conditions, precipitation was observed in the resist compositions.

[0079]

[Table 2]

[0080]

[Effects of the Invention] The positive photoresist composition of the present invention has excellent resolution, faithful reproducibility, cross-sectional shape of resist image, development latitude, heat resistance, and storage stability of the composition solution, and is suitable as a photoresist for microfabrication. used for.

Claims (1)

[Claims] 1. A positive photoresist composition comprising at least one photosensitive material represented by the following general formula (I) and an alkali-soluble resin. [Formula 1] Here, [Formula 2]