JP3275505B2 - Positive resist composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive resist composition, and more particularly to a positive resist composition for fine processing required for manufacturing semiconductor devices, magnetic bubble memory devices, integrated circuits and the like. .

[0002]

2. Description of the Related Art In order to form a fine pattern using a resist, a solution containing a photosensitive material (resist composition) is applied on a substrate and dried to form a photosensitive film.
Irradiation with actinic rays forms a latent image, which is then developed to create a negative or positive image. In order to manufacture a semiconductor device by microfabrication using a resist, usually, a silicon wafer is used as a substrate, an image (pattern) is formed by the above lithography technique, and then the resist remaining on the substrate is used as a protective film for etching. After that, the resist film is removed. The positive resist, giving a positive image an irradiated portion of the photosensitive film is solubility increases in the developer than the unexposed regions, the negative type resist, solubility of the irradiated portion of the photosensitive film is reduced To give a negative image.

Conventionally, as a resist composition for forming a semiconductor device, for example, a negative resist comprising a cyclized polyisoprene and a bisdiazide compound has been known. However, since this negative resist is developed with an organic solvent, it has a disadvantage that it cannot cope with the manufacture of a highly integrated semiconductor because it has a large swelling and a limited resolution. Further, a negative resist containing polyglycidyl methacrylate has high sensitivity but is inferior in resolution and dry etching properties.

On the other hand, it is considered that a positive resist composition is superior in resolution to this negative resist composition and can sufficiently cope with high integration of semiconductors.
At present, a positive resist composition generally used in this field comprises an alkali-soluble resin such as a novolak resin and a quinonediazide compound. This positive resist composition can be developed with an aqueous alkali solution and has excellent resolution. In addition, such a positive resist composition has been improved in resolution due to the improvement of its own performance and the performance of an exposure machine, and the formation of a fine pattern of 1 μm or less has become possible.

However, conventional positive resist compositions have not always obtained satisfactory results in terms of various characteristics such as sensitivity, residual film ratio, resolution, heat resistance, and storage stability.
Further improvements in performance are desired. 1 μm or less,
In particular, in the formation of a fine pattern of 0.8 μm or less, it is necessary to more strictly control the dimensions of the resist,
Therefore, a positive resist composition having higher dimensional accuracy has been strongly demanded.

Recently, it has been proposed to use quinonediazide sulfonic acid esters of various phenolic compounds as a photosensitizer in a positive resist containing an alkali-soluble phenol resin and a photosensitizer (see, for example, JP-A-2-296248). JP-A-2-296249
issue). However, the positive resist compositions specifically disclosed in these documents are somewhat insufficient in sensitivity, resolution, remaining film ratio, or pattern shape, and further improvement is required.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a positive resist composition which is excellent in balance among various properties such as sensitivity, residual film ratio, resolution, and pattern shape, and is particularly suitable for fine processing of 1 μm or less. To provide. The present inventors have conducted intensive studies to overcome the problems of the prior art, and as a result, (a) an alkali-soluble phenol resin, and (b) a quinonediazide sulfonic acid ester of a specific polyhydroxy compound as a photosensitizer, (C) It has been found that the object can be achieved by using a photosensitive material in combination with an aromatic compound having a phenolic hydroxyl group. The photosensitive material of the present invention, that is, the positive resist composition has an excellent balance among various properties such as sensitivity, residual film ratio, resolution, and pattern shape, and also has good heat resistance, storage stability, dry etching resistance, and the like. It is. The present invention has been completed based on these findings.

[0008]

Thus, according to the present invention, there is provided a photosensitive composition comprising (a) an alkali-soluble phenol resin, and (b) a quinonediazidesulfonic acid ester of a polyhydroxy compound represented by the following general formula (I). A positive resist composition comprising an agent and (c) an aromatic compound having a phenolic hydroxyl group.

[0009]

Embedded image k: 1 or 2. m: 1 or 2. R ^{1 to} R ⁴ : a halogen atom, an alkyl group, an alkenyl group,
An alkoxy group, an aryl group, or an acyl group, which may be the same or different. R ^{5 to} R ^{10 are a} hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkoxy group, an aryl group, or an acyl group, which may be the same or different. X: a single bond, -O -, - S -, - SO -, - SO 2 -,
-CO -, - CO ₂ -, cyclopentylidene, cyclohexylidene, phenylene,

[0010]

Embedded image (R ¹¹ and R ^{12 are a} hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a substituted aryl group, which may be the same or different from each other),

[0011]

Embedded image (R ^{13 to} R ^{16 are} hydrogen atoms or alkyl groups, which may be the same or different, and n is an integer of 1 to 5), or

[0012]

Embedded image (R ^{17 to} R ²⁰ : a hydrogen atom or an alkyl group, which may be the same or different).

Hereinafter, the present invention will be described in detail. (A) Alkali-soluble phenol resin Examples of the alkali-soluble phenol resin used in the present invention include a condensation reaction product of a phenol and an aldehyde, a condensation reaction product of a phenol and a ketone, and a vinylphenol polymer. And isopropenylphenol-based polymers, and hydrogenation products of these phenolic resins. Specific examples of the phenols used here include phenol, cresol, xylenol, ethylphenol, propylphenol, butylphenol, monovalent phenols such as phenylphenol, resorcinol, pyrocatechol, hydroquinone, bisphenol A, phloroglucinol, pyrogallol And other polyhydric phenols. Specific examples of aldehydes include formaldehyde, acetaldehyde, benzaldehyde, terephthalaldehyde, and the like. Specific examples of ketones include acetone, methyl ethyl ketone, diethyl ketone, diphenyl ketone, and the like. These condensation reactions can be performed according to a conventional method.

The vinylphenol-based polymer is selected from a homopolymer of vinylphenol and a copolymer of vinylphenol and a component copolymerizable with vinylphenol. Specific examples of the copolymerizable component include acrylic acid, methacrylic acid, styrene, maleic anhydride, maleic imide, vinyl acetate,
Acrylonitrile, and derivatives thereof, and the like. The isopropenylphenol-based polymer is selected from a homopolymer of isopropenylphenol and a copolymer of isopropenylphenol with a copolymerizable component.
Specific examples of the copolymerizable component include acrylic acid, methacrylic acid, styrene, maleic anhydride, maleic imide, vinyl acetate, acrylonitrile, and derivatives thereof. When a hydrogenation reaction product of a phenolic resin is used, the product can be produced by any known method. For example, it can be achieved by dissolving a phenol resin in an organic solvent and introducing hydrogen in the presence of a homogeneous or heterogeneous hydrogenation catalyst.

These alkali-soluble phenol resins may be used alone or in combination of two or more. Further, the alkali-soluble phenol resin may be used as it is, but may be separated by a known means to control the molecular weight and the molecular weight distribution. As a method of fractionation for the purpose of controlling the molecular weight and molecular weight distribution,
The resin is pulverized and solid-liquid extracted with an organic solvent having appropriate solubility, or the resin is dissolved in a good solvent and dropped into a poor solvent, or a solid-liquid or liquid is dropped by adding a poor solvent. -A method of liquid extraction and the like.

(B) Photosensitizer The photosensitizer used in the present invention has the general formula (I)
There is no particular limitation as long as it is a quinonediazidesulfonic acid ester of a polyhydroxy compound represented by For example, 1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-
Sulfonate, 1,2-naphthoquinonediazide-
Examples thereof include 5-sulfonic acid ester, 2,1-naphthoquinonediazide-4-sulfonic acid ester, 2,1-naphthoquinonediazide-5-sulfonic acid ester, and sulfonic acid esters of other quinonediazide derivatives.

The photosensitive agent used in the present invention can be synthesized by an esterification reaction between a phenol compound represented by the general formula (I) and a quinonediazidesulfonic acid compound. Examples of the quinonediazidesulfonic acid compound include 1,2-benzoquinonediazide-4-sulfonic acid,
1,2-naphthoquinonediazide-4-sulfonic acid,
2-naphthoquinonediazide-5-sulfonic acid, 2,1-
Examples thereof include o-quinonediazidesulfonic acid compounds such as naphthoquinonediazide-4-sulfonic acid and 2,1-naphthoquinonediazide-5-sulfonic acid, and other quinonediazidesulfonic acid derivatives.

The quinonediazidesulfonic acid ester used in the present invention is obtained by converting a quinonediazidesulfonic acid compound into a sulfonyl chloride with chlorosulfonic acid according to a conventional method, and obtaining the resulting quinonediazidosulfonyl chloride;
It is obtained by subjecting a polyhydroxy compound represented by the general formula (I) to a condensation reaction. For example, a predetermined amount of a polyhydroxy compound and 1,2-naphthoquinonediazide-5-sulfonyl chloride are dissolved in a solvent such as dioxane, acetone or tetrahydrofuran, and triethylamine, pyridine, sodium carbonate, sodium hydrogen carbonate,
A quinonediazidesulfonic acid ester can be prepared by adding and reacting a basic catalyst such as sodium hydroxide or potassium hydroxide, washing and drying the obtained product.

The polyhydroxy compound serving as a nucleus of the photosensitive agent used in the present invention is a compound represented by the above general formula (I). In the general formula (I), as the halogen atom, chlorine and bromine are preferable. As the alkyl group,
An alkyl group having 1 to 4 carbon atoms is preferred. The alkenyl group is preferably an alkenyl group having 2 to 5 carbon atoms. As the alkoxy group, an alkoxy group having 1 to 6 carbon atoms is preferable. As the aryl group, an aryl group having 6 to 15 carbon atoms is preferable. The substituted aryl group has 1 to 4 carbon atoms.
And an aryl group substituted with a halogen atom. Further, as the polyhydroxy compound represented by the general formula (I), a compound represented by the following general formula (II) is preferable.

[0020]

Embedded image R ^{21 to} R ^{22 are} hydrogen atoms or alkyl groups, which may be the same or different. As described above, the alkyl group is preferably an alkyl group having 1 to 4 carbon atoms. Specific examples of the polyhydroxy compound represented by the general formula (I), which is a mother nucleus of the photosensitive agent used in the present invention, include the following compounds (b-1) to (b-34).

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In the photosensitive agent used in the present invention, the esterification ratio (average esterification ratio) of the quinonediazidesulfonic acid compound to the polyhydroxy compound represented by the general formula (I) is not particularly limited. , Usually 20 to 100 of the OH group of the phenol compound.
%, Preferably 50 to 95%, more preferably 65 to 9%.
0% (expressed as mol% of the quinonediazidesulfonic acid compound with respect to the OH group). If the ratio of esterification is too low, pattern shape and resolution may be deteriorated. If the ratio of esterification is too high, sensitivity may be deteriorated.

The mixing ratio of the photosensitive agent used in the present invention is not particularly limited, but is usually 1 to 100 parts by weight with respect to 100 parts by weight of the alkali-soluble phenol resin.
Preferably 3 to 50 parts by weight, more preferably 10 to 40 parts by weight
Parts by weight. If the compounding ratio is too small, a sufficient residual film ratio cannot be obtained, leading to deterioration in resolution. Conversely, if the compounding ratio is too large, heat resistance deteriorates, which is not preferable. The photosensitive agents used in the present invention can be used alone or in combination of two or more. Further, another type of photosensitizer may be mixed with a small amount (generally, not more than 30% by weight of the total amount of the photosensitizer) within a range not to impair the object of the present invention. The other type of photosensitive agent to be mixed is not particularly limited, and any known quinonediazidesulfonic acid ester can be used.

(C) having a phenolic hydroxyl group
Aromatic compound The positive resist composition of the present invention contains an aromatic compound having a phenolic hydroxyl group (which may be simply referred to as a phenol compound). By adding a phenol compound, the alkali solubility of the alkali-soluble phenol resin can be promoted, and the sensitivity, residual film ratio, resolution, heat resistance, and the like of the positive resist composition can be improved. As the phenol compound used in the present invention,
Although it is not particularly limited as long as it is an aromatic compound having a phenolic hydroxyl group, the following general formula (III) and / or
Alternatively, an aromatic compound represented by the general formula (IV) is preferable.

[0058]

Embedded image R ²³ to R ^26: a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, an alkenyl group, an aryl group or an alkoxy group, it may be respectively the same or different. Y: single bond, -O -, - S -, - SO -, - SO 2 -,
-CO -, - CO ₂ -, cyclopentylidene, cyclohexylidene, phenylene,

[0059]

Embedded image (R ²⁷ and R ^{28 are a} hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a substituted aryl group, and may be the same or different from each other),

[0060]

Embedded image (R ^{29 to} R ^{32 are a} hydrogen atom or an alkyl group, and may be the same or different; p is an integer of 1 to 5),

[0061]

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[0062]

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[0063]

Embedded image Or

[0064]

Embedded image (R ³³ ~R ^36: a hydrogen atom or an alkyl group, each of which may be the same or different.) Is a linking group consisting of.

[0065]

Embedded image R ³⁷ to R ^42: a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, an alkenyl group, an aryl group or an alkoxy group, it may be respectively the same or different. R ⁴³ and R ^{44 are a} hydrogen atom, a halogen atom or an alkyl group, which may be the same or different. R ^{45 to} R ^{47 are} hydrogen atoms or alkyl groups, which may be the same or different.

In the above general formulas (III) and (IV), the halogen atom is preferably chlorine or bromine. As the alkyl group, an alkyl group having 1 to 4 carbon atoms is preferable. The alkenyl group is preferably an alkenyl group having 2 to 5 carbon atoms. The alkoxy group has 1 carbon atom
~ 6 alkoxy groups are preferred. As the aryl group,
An aryl group having 6 to 15 carbon atoms is preferred. As the substituted aryl group, an alkyl group having 1 to 4 carbon atoms or an aryl group substituted with a halogen atom is preferable. General formula (III)
The following compounds (c-1) to (c-62) can be given as specific examples of the aromatic compound represented by.

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Embedded image Specific examples of the aromatic compound represented by the general formula (IV) include the following compounds (c-63) to (c-66).

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Among these phenol compounds, c-
1, c-12, c-13, c-14, c-49, c-5
Compounds of 2, c-56, c-60, and c-64 are particularly preferred. The mixing ratio of these phenol compounds is usually 1 to 100 parts by weight based on 100 parts by weight of the alkali-soluble phenol resin. The preferred compounding ratio of the phenol compound varies depending on the composition, molecular weight, molecular weight distribution of the alkali-soluble phenolic resin, the type and the compounding ratio of the photosensitizer, and is generally 3 to 60 parts by weight. These phenol compounds can be used alone or in combination of two or more.

Solvent The positive resist composition of the present invention is usually used by dissolving it in a solvent in order to form a resist film by coating it on a substrate. Examples of the solvent include ketones such as acetone, methyl ethyl ketone, cyclohexanone, cyclopentanone and 2-heptanone; alcohols such as n-propyl alcohol, iso-propyl alcohol, n-butyl alcohol and cyclohexanol; ethylene glycol dimethyl ether, ethylene glycol Ethers such as diethyl ether and dioxane; alcohol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; propyl formate, butyl formate, propyl acetate, butyl acetate, methyl propionate,
Esters such as ethyl propionate, methyl butyrate, ethyl butyrate; methyl 2-oxypropionate, ethyl 2-oxypropionate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, methyl 2-ethoxypropionate, 2 Monooxycarboxylic acid esters such as ethyl ethoxypropionate; cellosolve esters such as cellosolve acetate, methyl cellosolve acetate, ethyl cellosolve acetate, propyl cellosolve acetate, butyl cellosolve acetate; propylene glycol, propylene glycol monomethyl ether, prolene glycol monomethyl ether Propylene glyco such as acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether Le acids; diethylene glycol monomethyl ether, diethylene glycol such as diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol et Chirueteru, diethylene glycol methyl ethyl ether; halogenated hydrocarbons such as trichlorethylene;
Aromatic hydrocarbons such as toluene and xylene; polar solvents such as dimethylacetamide, dimethylformamide and N-methylacetamide. These solvents can be used alone or in combination of two or more. These solvents are used in an amount sufficient to dissolve each component uniformly.

Other Components In order to improve developability, storage stability, heat resistance, etc., if necessary, styrene and acrylic acid, methacrylic acid or maleic anhydride may be added to the positive resist composition of the present invention. A copolymer with an acid, a copolymer with an alkene and maleic anhydride, a vinyl alcohol polymer, a vinylpyrrolidone polymer, rosin, shellac and the like can be added. The amount of the polymer is 0 to 50 parts by weight, preferably 5 to 20 parts by weight, based on 100 parts by weight of the alkali-soluble phenol resin. In the positive resist composition of the present invention, if necessary, a dye, a surfactant, a storage stabilizer,
Compatible additives such as sensitizers, striation inhibitors, and plasticizers can be included.

[0136] As the developer of the developer positive resist composition of the present invention, an aqueous solution of alkali include sodium hydroxide, potassium hydroxide, sodium silicate, inorganic alkalis such as ammonia; Primary amines such as ethylamine and propylamine; secondary amines such as diethylamine and dipropylamine; tertiary amines such as trimethylamine and triethylamine; alcohol amines such as dimethylmethanolamine and triethanolamine;
And quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, trimethylhydroxymethylammonium hydroxide, triethylhydroxymethylammonium hydroxide, and trimethylhydroxyethylammonium hydroxide. Further, if necessary, appropriate amounts of a water-soluble organic solvent such as methanol, ethanol, propanol, and ethylene glycol, a surfactant, a storage stabilizer, a resin dissolution inhibitor, and the like can be added to the aqueous alkali solution.

[0137]

The present invention will be described more specifically below with reference to examples and comparative examples. Parts and percentages are by weight unless otherwise specified. The resist evaluation method in the following examples and comparative examples is as follows. (1) Sensitivity Exposure time (msec) is the exposure energy amount that can form 1: 1 line & space of 0.60 μm according to design dimensions.
Expressed by (2) Resolution Indicates the critical resolution (μm) under the above exposure conditions. (3) Residual film ratio Indicates the ratio (%) of the resist film before and after development. (4) Pattern Shape The wafer on which the resist pattern was formed was cut from the direction perpendicular to the line pattern, and the result of observation with an electron microscope from the cross-sectional direction of the pattern was shown. The sidewalls of the pattern stand at an angle of 80 degrees or more with respect to the substrate,
Those with no film loss were judged as "good". Those in which the sidewalls were raised at an angle of less than 80 degrees were determined to be "tapered". Those with a small amount of film decrease were designated as "small film decrease", and those with a large film decrease were designated as "large film decrease".

Synthesis Example 1 (Synthesis of Novolak Resin A-1) In a flask equipped with a cooling tube and a stirrer, 385 g of m-cresol, 315 g of p-cresol, 360 g of 37% formalin, and oxalic acid dihydrate 2.49 g was charged and reacted for 2 hours while maintaining the temperature at 95 to 100 ° C. Thereafter, water is distilled off at 100 to 105 ° C. for 2 hours, and the temperature is further raised to 180 ° C. to 10 to 30 mmH.
g, and the unreacted monomer and water were removed. Then, the molten resin was returned to room temperature and collected, and the novolak resin (A-
515 g of 1) was obtained. The polystyrene-equivalent weight average molecular weight of this novolak resin as determined by gel permeation chromatography (GPC) was 7,000.

[Synthesis Example 2] (Synthesis of Novolak Resin A-2) 360 g of ethyl cellosolve acetate was added to and dissolved in 380 g of the novolak resin obtained in Synthesis Example 1. A dropping funnel was attached to the flask, and 950 g of toluene was dropped from the dropping funnel while controlling the temperature at 80 to 85 ° C, and the mixture was further heated at 80 ° C for 1 hour. Slowly cool to room temperature and add 1
Let stand for hours. After removing the supernatant liquid of the precipitated resin by decantation, 570 g of ethyl lactate (ethyl 2-oxypropionate) was added, and 100 mmH
g and heated to 100 ° C. to remove the residual toluene, thereby obtaining an ethyl lactate solution of the novolak resin (A-2). The polystyrene-equivalent weight average molecular weight of this novolak resin by GPC was 12,100.

[Synthesis Example 3] (Synthesis of Photosensitive Agent B-1) As the polyhydroxy compound, the compound of the above formula (b-7) was used.
2-Naphthoquinonediazide-5-sulfonic acid chloride was dissolved in dioxane to make a 10% solution. 20 ~
While controlling the temperature at 25 ° C., 1.2 equivalents of triethylamine of 1,2-naphthoquinonediazide-5-sulfonic acid chloride was added dropwise over 30 minutes, and the reaction was completed by holding for 2 hours. The precipitated solids are filtered,
The resultant was washed with ion-exchanged water and dried to obtain a photosensitive agent (B-1).

[Synthesis Example 4] (Synthesis of Photosensitive Agents B-2 to B-8) The kind of the polyhydroxy compound or the charged molar ratio of 1,2-naphthoquinonediazide-5-sulfonic acid chloride to the number of OH groups was changed. Except for this, photosensitive agents (B-2 to B-8) were synthesized according to the same formulation as in Synthesis Example 3. Table 1 shows the types and the molar ratios of the polyhydroxy compounds.

[Synthesis Example 5] (Synthesis of Photosensitive Agent B-9) As a polyhydroxy compound, 2,3,4,4'-tetrahydroxybenzophenone was used, and 1,2-naphthoquinonediazide-5 was added to the OH group. Synthesis Example 3 except that the charged molar ratio of sulfonic acid chloride was 85%.
A photosensitizer (B-9) was synthesized according to the same formulation as described above.

[Synthesis Example 6] A compound (d-1) represented by the following chemical formula was used as a polyhydroxy compound.
1,2-naphthoquinonediazide-5 for this OH group
Photosensitive agent (B-1) was prepared in the same manner as in Synthesis Example 3 except that the molar ratio of sulfonic acid chloride was changed to 80%.
0) was synthesized.

[0144]

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[0145]

[Table 1]

Examples 1 to 14 An alkali-soluble phenol resin (novolak resin) having the composition shown in Table 2, a photosensitizer, and an aromatic compound having a phenolic hydroxyl group (phenol compound) were treated with ethyl lactate (2-oxy (Ethyl propionate) was dissolved in a solvent, and the amount of the solvent was adjusted so that a film having a thickness of 1.17 μm could be applied. These solutions were filtered through a polytetrafluoroethylene fluoroethylene filter (PTFE filter) having a pore diameter of 0.1 μm to prepare a resist solution.

After the resist solution was applied on a silicon wafer by a spin coater, it was prebaked on a hot plate at 90 ° C. for 90 seconds to form a resist film having a film thickness of 1.17 μm. The silicon wafer on which the resist film was formed was exposed using an i-line stepper NSR-1755i7A (manufactured by Nikon Corporation, NA = 0.50) and a test reticle while changing the exposure time. Next, the wafer was exposed to a hot plate at 110 ° C. for 60 seconds and baked (Post Exposure Baking; PE).
After B), development was performed with a 2.38% aqueous solution of tetramethylammonium hydroxide at 23 ° C. for 1 minute by a paddle method to form a positive pattern. The wafer on which the pattern was formed was taken out, and the sensitivity, resolution, and pattern shape were observed with an electron microscope. The residual film ratio was determined by measuring the film thickness of a portion where a pattern was not formed on the wafer before and after development. Table 2 shows the evaluation results.

Comparative Example 1 A resist solution was prepared in the same manner as in Example 1 except that no phenol compound was used, and the resist was evaluated under the same conditions. Table 2 shows the results.
Shown in

[Comparative Example 2] A resist solution was prepared in the same manner as in Example 1 except that photosensitive agent B-9, which is a photosensitive agent outside the scope of the present invention, was used, and no phenol compound was used. The resist was evaluated under the same conditions. Table 2 shows the results.

Comparative Example 3 A resist solution was prepared in the same manner as in Example 1 except that the photosensitive agent B-10, which is a photosensitive agent outside the scope of the present invention, was used, and that no phenol compound was used. The resist was evaluated under the same conditions. Table 2 shows the results.

[0151]

[Table 2]

[0152]

According to the present invention, it is possible to provide a positive resist composition having excellent characteristics such as sensitivity, residual film ratio, resolution, and pattern shape. The positive resist of the present invention is particularly suitable for fine processing of 1 μm or less.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masahiro Nakamura 1-2-1 Yoko, Kawasaki-ku, Kawasaki-shi, Kanagawa Japan Zeon Corporation (56) References JP-A-2-285351 (JP, A) JP-A-3-228057 (JP, A) JP-A-5-216220 (JP, A) JP-A-5-72728 (JP, A) JP-A-5-53316 (JP, A) JP-A-5-127374 (JP) JP-A 64-44439 (JP, A) JP-A-4-122938 (JP, A) JP-A-3-200252 (JP, A) JP-A-6-167805 (JP, A) 6-202321 (JP, A) International Publication 90/1726 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03F ^7/ 00-7/42

Claims (6)

(57) [Claims] (1) an alkali-soluble phenol resin,
(B) a positive type comprising a photosensitizer comprising a quinonediazide sulfonic acid ester of a polyhydroxy compound represented by the following general formula (I); and (c) an aromatic compound having a phenolic hydroxyl group. Resist composition. Embedded image k: 1 or 2. m: 1 or 2. R ^{1 to} R ⁴ : a halogen atom, an alkyl group, an alkenyl group,
An alkoxy group, an aryl group, or an acyl group, which may be the same or different. R ^{5 to} R ^{10 are a} hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkoxy group, an aryl group, or an acyl group, which may be the same or different. X: a single bond, -O -, - S -, - SO -, - SO 2 -,
—CO—, —CO ₂ —, cyclopentylidene, cyclohexylidene, phenylene, (R ¹¹ and R ^{12 are a} hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a substituted aryl group, and may be the same or different from each other), (R ^{13 to} R ^{16 are a} hydrogen atom or an alkyl group, which may be the same or different, and n is an integer of 1 to 5), or (R ^{17 to} R ²⁰ : a hydrogen atom or an alkyl group, which may be the same or different). 2. The positive resist composition according to claim 1, wherein the polyhydroxy compound represented by the general formula (I) is a compound represented by the following general formula (II). Embedded image R ^{21 to} R ^{22 are} hydrogen atoms or alkyl groups, which may be the same or different. 3. The positive resist composition according to claim 1, wherein the aromatic compound having a phenolic hydroxyl group is an aromatic compound represented by the following general formula (III). Embedded image R ²³ to R ^26: a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, an alkenyl group, an aryl group or an alkoxy group, it may be respectively the same or different. Y: single bond, -O -, - S -, - SO -, - SO 2 -,
—CO—, —CO ₂ —, cyclopentylidene, cyclohexylidene, phenylene, (R ²⁷ and R ^{28 are a} hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a substituted aryl group, which may be the same or different from each other), (R ^{29 to} R ^{32 are a} hydrogen atom or an alkyl group, which may be the same or different, and p is an integer of 1 to 5), Embedded image Embedded image Or (R ³³ ~R ^36: a hydrogen atom or an alkyl group, each of which may be the same or different.) Is a linking group consisting of. 4. The positive resist composition according to claim 1, wherein the aromatic compound having a phenolic hydroxyl group is an aromatic compound represented by the following general formula (IV). Embedded image R ³⁷ to R ^42: a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, an alkenyl group, an aryl group or an alkoxy group, it may be respectively the same or different. R ⁴³ and R ^{44 are a} hydrogen atom, a halogen atom or an alkyl group, which may be the same or different. R ^{45 to} R ^{47 are} hydrogen atoms or alkyl groups, which may be the same or different. 5. An aromatic compound represented by the general formula (III): Embedded image Embedded image Embedded image Embedded image Or 4. The positive resist composition according to claim 3, wherein 6. An aromatic compound represented by the general formula (IV): The positive resist composition according to claim 4, wherein