KR101308267B1 - Positive photoresist composition containing a silicon based surfactant having a solubility in water·oil based solvent - Google Patents

Abstract

The present invention introduces a silicone-based surfactant having solubility in water- and oil-based solvents in the liquid crystal display device manufacturing process to significantly lower the contact angle of the resist surface to improve the adhesion to the metal that can be deposited on the resist, and has good leveling properties It has good affinity with a developing solution, which is advantageous for high sensitivity of the resist, and can be developed in an aqueous solution of potassium hydroxide, which is newly required to be used as a developing solution, improving adhesion at the interface of the substrate, and excellent wet etching ability. It provides a photoresist composition.

Photoresist, silicone surfactant, liquid crystal display device, modified epoxy acrylate

Description

Positive photoresist composition containing a silicon based surfactant having a solubility in water oil based solvent

The present invention relates to a photoresist composition using a surfactant having solubility in an aqueous and oil-based solvent. More specifically, the present invention relates to positive photoresist compositions that can be used for LCD patterning.

In general, as a composition for positive photoresist, a composition containing a binder resin soluble in an alkaline developer such as resol or cresol novolak resin and a dissolution inhibitor having a quinonediazide group is suitable. Widely used in lithography.

Such lithography techniques are widely used in the field of liquid crystal display device manufacturing in that they can form a pattern of a resist having excellent resolution and shape. Unlike the conventional semiconductor manufacturing process, the semiconductor manufacturing process in recent years uses a large area substrate (eg, 1100x1300mm), so that in the liquid crystal display device process, the uniformity of the applied film, the uniformity of the size of the formed pattern, dry, wet etching resistance, And stain suppression ability is required. In addition, in order to manufacture a liquid crystal display element, since very much resist material is consumed, it was required to be an inexpensive material in addition to such a characteristic.

The liquid crystal display device manufacturing process to which such lithography technology can be applied can be largely divided into a TFT process and a color filter process. First, the TFT process was developed and developed into a 5-mask, 4-mask, and 3-mask process, and in particular, it required high sensitivity, high resolution, and high heat resistance of the resist. In an effort to obtain such high resolution and high heat resistance, Japanese Patent Application Laid-Open Nos. 9-90662 and 10-69077 disclose quinonediazide sulfonic acid esters having sulfonic acid groups at 4 or 5 positions. It was suggested that an excellent pattern was formed by forming an ester using a quinone diazide compound, and in Japanese Patent Application Laid-Open Nos. 56-209424 and 56-206425, bisazide compounds were used. A resist having a resolution has been proposed. In the color filter process, positive and negative resists are used in combination. As is known, the developer of the negative resist and the developer of the positive resist are different from each other, which is inconvenient in the process. The negative resist is mainly used in the color resist pattern, and the developing solution uses aqueous potassium hydroxide solution. On the other hand, the positive resist used for the ITO pattern uses the tetramethylammonium hydroxide aqueous solution as a developing solution.

In order to remove such inconvenience in the process and to lower the manufacturing cost, there has been a movement to change the developer of the positive resist used in the color filter process into an aqueous potassium hydroxide solution, and some are currently using potassium hydroxide developer.

However, existing compositions for amphoteric photoresists, for example, compositions containing a binder resin soluble in an alkaline developer such as resol or cresol novolak resin and a dissolution inhibitor having a quinonediazide group are used in a low potassium hydroxide solution. The pattern could not be formed or the sensitivity was too slow to be used. For that reason, different compositions and various ideas are needed to significantly increase or control the development of existing novolac compositions.

SUMMARY OF THE INVENTION An object of the present invention is to account for the above-mentioned problems. In the manufacturing process of a liquid crystal display device, a silicone-based surfactant having solubility in water- and oil-based solvents is introduced to significantly lower the contact angle on the surface of the resist, thereby improving adhesion to a metal that can be deposited on the resist. It improves, has good leveling property, and has good affinity with a developing solution, which is advantageous for high sensitivity of the resist, and can be developed by an aqueous potassium hydroxide solution, which is newly required to be used as a developing solution, and adhesion at the interface of the substrate. This is to provide a positive photoresist composition with improved wet etching capability.

The above object can be attained by improving the solubility in a developer by incorporating a silicone-based surfactant having solubility in an aqueous and oil-based solvent in the photoresist composition, and furthermore, by containing a modified epoxy acrylate resin. This can be achieved by improving it.

The positive photoresist composition according to the present invention is characterized by containing a compound represented by the following formula (1) or (2).

(Wherein a, b and c each represent a hydrogen atom or an alkyl or alkoxy group having 1 to 10 carbon atoms, and l, m and n each represent an integer of 1 to 10)

(Wherein a, b, c and d represent a hydrogen atom or an alkyl or alkoxy group having 1 to 10 carbon atoms, and l, m, n, o and p each represent an integer of 1 to 10)

The compounds of the formulas (1) and (2) may be commercially available as surfactants, and examples thereof include surfactants (trade names: A-008 and D-208) manufactured by Siltech.

The composition may further contain an alkali-soluble resin and a dissolution inhibitor, each of 70 to 90 parts by weight of an alkali-soluble resin, 5 to 15 parts by weight of a dissolution inhibitor, and 0.01 to 0.5 parts by weight of a compound of Formula 1 or 2, respectively. It is preferable to contain a part.

When the alkali-soluble resin is contained in less than 70 parts by weight in the above composition, pattern formation is difficult, and when contained in more than 90 parts by weight, development defects such as scum are likely to occur at the end of the pattern. In addition, when the dissolution inhibitor is contained in less than 5 parts by weight of the composition, it is difficult to form a pattern, there is a problem in the residual film ratio, etc., if contained in more than 15 parts by weight, problems such as scum or residue occurs. In addition, when the compound of Formula 1 or 2 is contained in less than 0.01 parts by weight of the composition, there is a problem of unevenness of the substrate, and when contained in more than 0.5 parts by weight occurs a non-uniformity of the coating film.

The alkali-soluble resin used in the present invention is not particularly limited, and those known in the art can be used, and it is preferable to use a novolak resin.

In addition, alkali-soluble resin used by this invention contains resin which is itself insoluble or poorly soluble in aqueous alkali solution, but becomes soluble in aqueous alkali solution by the action of an acid after exposure. Alkali-soluble resins having these characteristics can be used with acid generators, and can also be used with modified novolac resins (compounds of Formula 3). When the composition of the present invention contains such an alkali-soluble resin, an acid generator and a modified novolak resin, it is preferable to use the acid generator in an amount of 1 to 10% by weight based on the total alkali-soluble resin. It is preferable to contain a volak resin in 70 weight% or less in the content of all alkali-soluble resin.

The positive photoresist composition of the present invention may contain a modified novolak resin represented by the following formula (3) as part of the novolak resin, wherein the compound of formula (3) is contained in 70% by weight or less of the total novolak resin content desirable. The compound of Formula 3 can be used 1 type or in combination of 2 or more types.

And when the compound of Formula 3 exceeds 70% by weight in the total content of the novolak resin, the residual film rate is lowered, there is a problem that scum can be formed on the lower substrate.

(In the above formula, R ₁ and R ₂ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R ₃ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 15 carbon atoms, and 7 to 15 carbon atoms. An aralkyl group, an alkenyl group having 2 to 10 carbon atoms, an alkylcarbonyl group having 2 to 10 carbon atoms, an alkenylcarbonyl group having 3 to 10 carbon atoms, an arylcarbonyl group having 7 to 15 carbon atoms, or an aralkylcarbonyl group having 8 to 15 carbon atoms; , R ₁ and R ₂ are each independently a hydrogen atom or a methyl group, R ₃ is a hydrogen atom, an alkylcarbonyl group having 2 to 10 carbon atoms, an alkenylcarbonyl group having 3 to 10 carbon atoms, an arylcarbonyl group having 7 to 15 carbon atoms or 8 to C carbon atoms An aralkylcarbonyl group of 15. The alkyl group, aryl group, aralkyl group, alkenyl group, alkylcarbonyl group, alkenylcarbonyl group, arylcarbonyl group The aralkylcarbonyl group may be optionally substituted with a carboxyl group, an oxycarbonyl group, a hydroxy group, an alkoxy group having 1 to 5 carbon atoms or an alkyl group having 1 to 5 carbon atoms, wherein the alkyl group and the alkenyl group are linear, branched and Cyclic group, n represents an integer of 1 to 10.)

The compound terminal of Formula 3 is a hydrogen atom. It is preferable that the compound of Formula 3 has a weight-average molecular weight measured by gel permeation chromatography (GPC) of 500 to 20,000 in terms of polystyrene. Specific examples of the compound corresponding to Formula 3 include the following compounds, and the compounds of Formulas 3a, 3b and 3c below are preferably used in the present invention.

The compound of Formula 3 may be prepared by the following steps (a) or (b):

(a) 0.1 to 1% by weight of the reaction catalyst selected from the group consisting of triphenylphosphine, triethylamine, benzyldimethylamine, methyltriethylammonium chloride, chromium octanoate and zirconium octanoate In an organic solvent, at a temperature of 90 to 110 ° C., the epoxy compound of the following formula (4) and acrylic acid of the formula (5) are reacted with a reaction ratio of 0.8 to 1.2 moles of acrylic acid, preferably 1 mole to 1 equivalent of the epoxy group. Obtaining modified epoxy acrylate of the formula (6):

(Wherein R ₁ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms and n represents an integer of 1 to 10)

(Wherein R ₂ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms)

(Wherein R ₁ and R ₂ each represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms and n represents an integer of 1 to 10)

(b) a reaction of 0.8 to 1.2 moles, preferably 1 mole of an acid anhydride, with respect to 1 equivalent of the hydroxy group of the formula (6) at one of the reaction product of step (a) and the acid anhydride of formula (7) at a temperature of 70 ~ 90 ℃ Reacting in a ratio to obtain a compound of Formula 3 wherein the carboxylic acid residue is introduced at the terminal or side chain:

As the compound of the formula (3), a commercially available one can also be used, and examples thereof include resin (trade name: PR-310) produced by Showa Kobunshi K.K.

Alkali-soluble resin used by this invention is obtained by addition-condensation reaction of a phenol compound and an aldehyde compound. Examples of the phenolic compound include phenol, o-, m- and p-cresol, 2,5-xylenol, 3,5-xylenol, 3,4-xylenol, 2,3,5-trimethylphenol, 4-t-butylphenol, 2-t-butylphenol, 3-t-butylphenol, 3-ethylphenol, 2-ethylphenol, 4-ethylphenol, 3-methyl-6-t-butylphenol, 4-methyl One or a mixture of two or more selected from 2-t-butylphenol, 2-naphthol, 1,3-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, and 1,5-dihydroxynaphthalene may be used. .

Examples of aldehyde compounds used in the production of novolac resins include formaldehyde, paraformaldehyde, acetaldehyde, propylaldehyde, benzaldehyde, phenylaldehyde, α- and β-phenylpropyl aldehydes, o-, m- and p-hydroxybenzaldehyde , Glutaraldehyde, glyoxal, o- and p-methylbenzaldehyde and the like.

The addition-condensation reaction between the phenol compound and the aldehyde compound is carried out in a conventional manner in the presence of an acid catalyst. As reaction conditions, a temperature is usually 60-250 degreeC, and reaction time is 2-30 hours in general. Examples of the acid catalyst include organic acids such as oxalic acid, formic acid, trichloroacetic acid, p-toluenesulfonic acid, and the like; Inorganic acids such as hydrochloric acid, sulfuric acid, perchloric acid, phosphoric acid, and the like; And divalent metal salts such as zinc acetate, magnesium acetate and the like. The addition-condensation reaction is carried out in a suitable solvent or in bulk. The alkali-soluble resin produced by the addition-condensation reaction preferably has a weight average molecular weight of 2,000 to 50,000 in terms of polystyrene.

The dissolution inhibitor of the present invention acts on the alkali-soluble resin to lower the dissolution rate. As the dissolution inhibitor, an ester compound of a phenolic compound having a hydroxyl group and a quinonediazide sulfonic acid compound is used. Specific examples of the quinonediazide sulfonic acid compound herein include o-quinonediazide sulfonic acid. Specific examples of the ester compound include phenolic polyhydroxy compounds having at least three hydroxy groups, and 1,2-naphthoquinone diazide-5- or -4-sulfonic acid or 1,2-benzoquinone diazide Preferred are ester compounds of 4-sulfonic acid.

Such radiation-sensitive quinonediazide compounds may also be used alone or in combination of two or more thereof.

Such esters can be obtained by reacting a phenolic compound having a hydroxy group with an o-quinonediazidesulfonyl halide in the presence of a base such as triethylamine in a suitable solvent. After completion of the reaction, suitable post-treatment can be carried out to separate the desired quinonediazidesulfonic acid ester. Such post-treatment may include, for example, a method of mixing a reactant with water to precipitate a desired compound, filtering and drying to obtain a powdery product; The reaction is treated with a resist solvent such as 2-heptanone, washed with water, phase separated, and the solvent is removed by distillation or equilibrium flash distillation to obtain the product in the form of a solution in the resist solvent. Equilibrium flash distillation here refers to a kind of continuous distillation that distills a portion of the liquid mixture and separates the vapor into liquid phase when the resulting vapor is brought into sufficient contact with the liquid phase. This method is suitable for the concentration of the thermosensitive material because it has a very good vaporization rate, vaporization takes place in an instant, and the equilibrium between the vapor and the liquid phase is rapid.

The positive photoresist composition of the present invention can use potassium hydroxide as a developer.

The positive photoresist composition of the present invention is applied to a substrate such as a silicon wafer in the form of a resist solution in which the above components are dissolved in a solvent. Any solvent or resist solution can be used as long as it can dissolve the components, have a suitable drying rate, and can form a uniform and smooth coating film after evaporation of the solvent. The solvent may be used that is commonly used in the art. Examples of the solvent include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate, propylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate; Glycol ethers such as ethyl cellosolve, methyl cellosolve, propylene glycol monomethyl ether and propylene glycol monoethyl ether; Esters such as ethyl acetate, butyl acetate, amyl acetate and ethyl pyruvate; Ketones such as acetone, methyl isobutyl ketone, 2-heptone and cyclohexanone; And cyclic esters such as γ-butyrolacetone. These solvents may be used alone or in combination of two or more.

The resist film formed by applying a resist solution and drying is patterned by irradiation with radiation. Then, if necessary, after the post-exposure bake, the irradiated resist film is developed with an alkali developer. The alkali developer used herein is a variety of aqueous alkali developers known in the art. Widely used developers include aqueous solutions of tetramethyl ammonium hydroxide and aqueous solutions of (2-hydroxyethyl) trimethyl ammonium hydroxide (commonly referred to as choline) and aqueous potassium hydroxide solution and surfactants. Potassium aqueous solution (product manufactured by JSR) (trade name: JCD).

Hereinafter, the present invention will be described in more detail with reference to Preparation Examples and Examples, but these Preparation Examples and Examples do not limit the scope of the present invention. In preparations and examples, all percentages, parts and ratios indicating content or amount used are by weight unless otherwise indicated. The weight average molecular weight is a value measured by GPC using polystyrene as a standard.

Manufacturing example  1: denaturation Novolac  Preparation of Resin (Compound of Formula 3, Resin A)

While injecting nitrogen, 210 parts of YDCN-500-90P (epoxy cresol novolak resin, manufactured by Kukdo Chemical Co., Ltd.), 200 parts of butylcarbitol acetate, and 1 part of hydroquinone were placed in a reaction vessel, and heated and stirred at 80 ° C. for 1 hour to uniform contents. Mixed well. Add 1 part of triethylamine and add 72 parts of acrylic acid while maintaining it at 90 ° C, and react for 2 to 4 hours. When acrylic acid is added, an epoxy ring opens and a serious exotherm starts. After the reaction was completed, the reaction product was cooled to room temperature, and then 152 parts of tetrahydrophthalic anhydride and 100 parts of butylcarbitol acetate were added and reacted for 1 to 2 hours while maintaining the reaction temperature at 100 to 110 ° C. 1780.1850 cm ^-1 After confirming that there is no absorption peak of the anhydride functional group in the quenching temperature of the reactant to room temperature. Hereinafter, this novolak resin is called resin A. This resin had a weight average molecular weight of about 7,200 and an acid value of 60 to 85 mg-KOH / g.

Preparation Example 2: Novolac  Preparation of Resin (B)

In the reactor, 479.7 parts of mixed m- / p-cresol containing 62% m-cresol, 115.1 parts of p-cresol, 268.75 parts of 2,5-xylenol, 39.3 parts of oxalic acid dihydrate, 261.8 parts of 90% acetic acid aqueous solution, and 803.1 parts of methyl isobutyl ketone were charged and the mixture was heated to 80 ° C. 463.2 parts of 37% formalin was added dropwise to the mixture over 30 minutes. The mixture was heated to 92 ° C. and reacted at this temperature for 13 hours while refluxing continued. After the reaction was completed, 486.2 parts of methyl isobutyl ketone were added, the mixture was washed with 1823.2 parts of water, and then the oil phase was separated. This operation was repeated six times. Thereafter, the oil phase was concentrated to obtain a novolak resin solution in methyl isobutyl ketone. The resin had a weight average molecular weight of about 4,400. The solution was diluted with methyl isobutyl ketone until the concentration reached 20%. 545.2 parts of n-heptane was added to 400 parts of 20% solutions, stirring. The mixture was further stirred at 60 ° C. for 30 minutes, allowed to stand and phase separated. Thereafter, 76.3 parts of the lower layer was diluted with 400 parts of 2-heptanone, and concentrated to obtain 109.7 parts of a novolak resin solution in 2-heptanone. Hereinafter, this novolak resin is called resin B. This resin had a weight average molecular weight of about 7,200 and a ratio of about 20% of the GPC pattern region corresponding to a molecular weight of 1,000 or less.

Preparation Example 3: Novolac  Preparation of Resin (C)

The reactor was charged with 486.6 parts of m-cresol, 219.6 parts of 2,5-xylenol, 31.8 parts of oxalic acid dihydrate, 214.2 parts of 90% acetic acid aqueous solution and 635.0 parts of methyl isobutyl ketone, and the mixture was heated to 80 ° C. 450.9 parts of 37% formalin was added dropwise to the mixture over 30 minutes. The mixture was heated to 92 ° C. and reacted at this temperature for 11 hours while refluxing continued. After the reaction was completed, 461.5 parts of methyl isobutylketone was added, the mixture was washed with 1500 parts of water, and then the oil phase was separated. This operation was repeated six times. Thereafter, the oil phase was concentrated to obtain a novolak resin solution in methyl isobutyl ketone. The resin had a weight average molecular weight of about 4,800. The solution was diluted with methyl isobutyl ketone until the concentration reached 22%. 271.2 parts of n-heptane was added to 400 parts of 22% solutions, stirring. The mixture was further stirred at 60 ° C. for 30 minutes, allowed to stand and phase separated. Thereafter, 91.4 parts of the lower layer was diluted with 400 parts of 2-heptanone, and concentrated to obtain 135.8 parts of a novolak resin solution in 2-heptanone. Hereinafter, this novolak resin is called resin C. This resin had a weight average molecular weight of about 6,100 and a ratio of GPC pattern region corresponding to a molecular weight of 1,000 or less was about 20%.

 Examples 1-16 and Comparative example  1-2

80 parts by weight of novolak resins A and B and C obtained in Preparation Examples 3, 4 and 5 in 2-heptanone as a solvent and in solids (A, B and C in Examples and Comparative Examples, respectively, 4,4 parts by weight of 4,4 '-(2-hydroxybenzylidene) di-2,6-xylenol as an additive (low molecular weight phenolic compound), as a dissolution inhibitor component, and a reaction molar ratio. 2,6-bis [4-hydroxy-3- (2-hydroxy-5-methylbenzyl) -2,5-dimethylbenzyl] -4-methylphenol and 1,2-naphtho having a ratio of 1: 2.2 10 parts by weight of a condensate (powder form) of quinonediazide-5-sulfonyl chloride, and a silicone-based surfactant of Formula 1 or 2 having solubility in an aqueous and oil-based solvent (Table 1 and Added at the ratio shown in 2), and dissolved, so that the total amount of the 2-heptanone solution including the amount of the novolak resin solution was 150 parts by weight.

Each solution obtained was filtered with a fluororesin filter to obtain a resist solution. The resist solution was spin-coated on a silicon wafer treated with hexamethylcysilazane and pre-baked at 90 ° C. for 60 seconds directly on a hot-plate to form a resist film having a thickness of 1.50 μm. The wafer with the resist film was line-and-space patterned with an i-line stepper ("NSR-2005 i9C", manufactured by Nikon Co., Ltd., NA = 0.57, sigma = 0.60) while gradually changing the exposure dose. The exposure process was carried out using. The wafer was then subjected to post-exposure bake for 60 seconds at 110 ° C. on a hot plate, followed by paddle development for 60 seconds using a 2.38% aqueous tetramethylammonium hydroxide solution and 0.04% potassium hydroxide developer.

The developed pattern was observed by visual and scanning electron microscopy. Developability, effective sensitivity, and resolution were evaluated for each pattern by the following method. The results are shown in Tables 1 and 2 below.

1) Developability: After 60 seconds of paddle development in post-exposure developer, visually confirm the pattern formation. If a pattern is formed on the wafer after development,? Is not formed, but if a resist remains on the wafer,?, If the resist is developed and hardly remains on the wafer, it is referred to as X; or Y if the resist is not developed.

2) Effective sensitivity: The exposure amount when the cross section of a 5.0-micrometer line-and-space pattern is 1: 1. If no pattern is formed, no measurement is made. If no pattern is formed but a resist remains on the wafer,?, And if a resist is developed and hardly remains on the wafer, it is referred to as X.

3) Resolution: When exposed with effective sensitivity, it represents the minimum minimum line width of the line-and-space pattern. If no pattern is formed, no measurement is made. Therefore, if no pattern is formed but a resist remains on the wafer,?, And if a resist is developed and hardly remains on the wafer, it is referred to as X.

4) Heat resistance: When observing the pattern cross section and comparing it with not bending, if the shape change is small, it is ○. If the pattern is not formed, the measurement is not possible. If the pattern is not formed but the resist remains on the wafer, (Triangle | delta), and if a resist develops and hardly remain on a wafer, it is called X.

5) Leveling property: After coating resist on third generation glass substrate, baking and removing solvent, measure 20 points on substrate, and if film uniformity is within 1 ~ 3%, it will be ○, and if it is between 3 ~ 10% (Triangle | delta), When it is 10% or more, it is called X.

6) Contact angle: After the resist is coated on the bare wafer, drop a drop of ultrapure water with a micro syringe, and measure the angle of water on the wafer surface.

As shown in Tables 1 and 2, in the case of the example products using a water-soluble silicone-based surfactant, the developability was improved to form a good pattern even in an aqueous potassium hydroxide solution, and excellent characteristics in effective sensitivity, resolution, heat resistance, and leveling property. Indicated. However, comparative products without surfactants did not develop in aqueous potassium hydroxide solution and showed poor results in other properties. In addition, in the case of using a modified novolac resin showed an excellent effect in the effective sensitivity compared to the case where not.

The resist composition according to the present invention significantly lowers the coating surface contact angle by using a water-soluble silicone surfactant to improve adhesion with metals that can be deposited on the resist, has good leveling properties, and has a good affinity with a developer. It is advantageous for high sensitivity. In addition, it has been found that the composition of the conventional general positive resist has excellent sensitivity and resolution in potassium hydroxide aqueous solution, which is difficult to develop or high sensitivity, and excellent resist performance such as heat resistance.

Claims (9)

A positive photoresist composition comprising 70 to 90 parts by weight of an alkali-soluble resin, 5 to 15 parts by weight of a dissolution inhibitor, and 0.01 to 0.5 parts by weight of a compound of Formula 1 or 2 below:

(One) (In the above formula, a, b and c each represent a hydrogen atom or an alkyl or alkoxy group having 1 to 10 carbon atoms, and l, m and n each represent an integer of 1 to 10.)

(2) (Wherein a, b, c and d each represent a hydrogen atom or an alkyl or alkoxy group having 1 to 10 carbon atoms and represents an alkyl or alkoxy group, and l, m, n, o and p each represent an integer of 1 to 10). Indicates). delete The positive photoresist composition according to claim 1, wherein the alkali-soluble resin is a novolak resin, and the dissolution inhibitor is an ester compound of a phenolic compound having a hydroxyl group and a quinonediazide sulfonic acid compound. The positive photoresist composition according to claim 1, wherein the alkali-soluble resin has a weight average molecular weight of 2,000 to 50,000 in terms of polystyrene. The positive photoresist composition according to claim 3, wherein the novolak resin contains a modified novolak resin represented by the following Chemical Formula 3 at 70 wt% or less of the total novolak resin content:

(3) Wherein R ₁ and R ₂ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R ₃ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 15 carbon atoms, and 7 to 15 carbon atoms An aralkyl group, an alkenyl group having 2 to 10 carbon atoms, an alkylcarbonyl group having 2 to 10 carbon atoms, an alkenylcarbonyl group having 3 to 10 carbon atoms, an arylcarbonyl group having 7 to 15 carbon atoms, or an aralkylcarbonyl group having 8 to 15 carbon atoms, and the alkyl group , An aryl group, an aralkyl group, an alkenyl group, an alkylcarbonyl group, an alkenylcarbonyl group, an arylcarbonyl group or an aralkylcarbonyl group is optionally a carboxyl group, an oxycarbonyl group, a hydroxy group, an alkoxy group having 1 to 5 carbon atoms or an alkyl group having 1 to 5 carbon atoms In addition, the alkyl group, alkenyl group includes a straight chain, branched chain and a cyclic group in the above, n is 1 to 10 of It indicates the number.). The positive photoresist composition according to claim 5, wherein the modified novolak resin has a weight average molecular weight of 500 to 20,000 in terms of polystyrene. The positive photoresist composition of claim 5, wherein the modified novolak resin comprises at least one selected from the group consisting of compounds represented by Formulas 3a, 3b, and 3c:

(3a)

(3b)

(3c) (Wherein R ₁ , R ₂ and n are each as defined in claim 5). The resin according to claim 1, wherein the alkali-soluble resin is a resin which is itself insoluble or poorly soluble in an aqueous alkali solution, but becomes soluble in an aqueous alkali solution by the action of an acid after exposure, and a modified novolac resin represented by the following formula (3): A positive photoresist, wherein the modified novolac resin is contained in an amount of 70% by weight or less in the total alkali-soluble resin content, and further contains an acid generator in an amount of 1 to 10% by weight based on the total alkali-soluble resin. Composition:

(3) Wherein R ₁ and R ₂ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R ₃ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 15 carbon atoms, and 7 to 15 carbon atoms An aralkyl group, an alkenyl group having 2 to 10 carbon atoms, an alkylcarbonyl group having 2 to 10 carbon atoms, an alkenylcarbonyl group having 3 to 10 carbon atoms, an arylcarbonyl group having 7 to 15 carbon atoms, or an aralkylcarbonyl group having 8 to 15 carbon atoms, and the alkyl group , An aryl group, an aralkyl group, an alkenyl group, an alkylcarbonyl group, an alkenylcarbonyl group, an arylcarbonyl group or an aralkylcarbonyl group is optionally a carboxyl group, an oxycarbonyl group, a hydroxy group, an alkoxy group having 1 to 5 carbon atoms or an alkyl group having 1 to 5 carbon atoms In addition, the alkyl group, alkenyl group includes a straight chain, branched chain and a cyclic group in the above, n is 1 to 10 of It indicates the number.). 9. A positive photoresist composition according to any one of claims 1 and 3 to 8, wherein potassium hydroxide is used as a developer.