JP2005097331A - Production method of phenol resin for photoresist, and photoresist composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for efficiently producing a phenol resin for photoresist, whereby contamination of a production line due to a sublimate in a photoresist resin is reduced, enhancing the productivity; and a resin composition for photoresist containing the phenol resin for photoresist produced thereby. <P>SOLUTION: The production method for the phenol resin for photoresist includes the following: (a) a step for reacting a phenol with an aldehyde to synthesize a phenol resin A, (b) a step for reacting the phenol resin A dissolved in an organic solvent with an aldehyde in the presence of a solid catalyst to synthesize a phenol resin B, and (c) a step for subjecting the phenol resin B to separation from the solid catalyst and then to reaction and/or concentration. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing a phenol resin for a photoresist and a photoresist composition.

In general, a positive photoresist uses a photosensitizer having a quinonediazide group such as a naphthoquinonediazide compound and an alkali-soluble resin (for example, a novolac-type phenolic resin).
A positive photoresist having such a composition exhibits a high resolving power by developing with an alkaline solution after exposure, and is used for manufacturing semiconductors such as IC and LSI, display screen devices such as LCDs, and printing masters. Yes. In addition, novolak type phenolic resin has high heat resistance due to the structure having many aromatic rings against plasma dry etching, and so far it contains novolak type phenolic resin and naphthoquinone diazide photosensitizer. Many positive-type photoresists have been developed and put to practical use and have achieved great results.

  As the positive photoresist, a novolak type phenol resin obtained by reacting m / p-cresol and formaldehyde in the presence of an acid catalyst is generally used. In order to adjust or improve the photoresist characteristics, the ratio of m / p-cresol used as raw material phenols, the molecular weight of the phenol resin, the molecular weight distribution, and the like have been studied.

  However, in a photoresist to which a phenol resin obtained by a general method from m / p-cresol and formaldehyde is applied, for example, in a manufacturing process of an LCD, a low-nuclear component of a phenol resin in the photoresist. Sublimation of (mainly binuclear components) causes the sublimate to accumulate on the production line and contaminate the product, causing a reduction in product yield. For this reason, the reduction | decrease request | requirement of the binuclear component contained in a phenol resin has become very high.

Such a phenol resin with a low content of a binuclear component is a method such as solvent fractionation (for example, see Patent Document 1), and removal of the binuclear component by steam distillation (for example, see Patent Document 2). There are examples that are synthesized.
The solvent fractionation method is a method that utilizes the difference in solubility of the phenol resin with respect to the good solvent and the poor solvent, but there is no clear difference in solubility between the low-nuclear components of the phenol resin. It is difficult to remove selectively. For this reason, excess resin was removed, resulting in a disadvantage that the batch yield was reduced and the production was not possible at a low cost. In addition, since the removal efficiency of the dinuclear component is low, repeated operations are required, and a large amount of solution of the removed component is generated, resulting in a high environmental load.

On the other hand, the steam distillation method is a technique in which high-pressure steam is blown into a phenol resin under vacuum conditions to forcibly remove dinuclear components by azeotropic action. Due to the difference in boiling point, the selectivity for removing binuclear components is high. However, not only is it necessary to have robust equipment that can withstand bumping and explosion phenomena that occur when steam is blown into high-temperature resin, but a large amount of high-pressure steam is generated to keep the resin at a high temperature for a long time. Not only can it be manufactured at low cost, such as the need for thermal energy, the generation of agglomerated water with dissolved binuclear components as industrial waste, and the technical and environmental aspects of implementation on an industrial scale. The production barrier was an influential barrier.

JP-T-2001-506294 Japanese Patent Application Laid-Open No. 11-246643

  The present invention relates to a method for efficiently producing a phenol resin for a photoresist capable of reducing the contamination of the production line due to sublimates in the photoresist resin and improving the productivity, and a photo obtained by this production method. The present invention provides a photoresist resin composition containing a resist phenol resin.

Such an object is achieved by the following present inventions (1) to (9).
(1) A method for producing a phenol resin for a photoresist, comprising the following steps (a) to (c):
(A) a step of reacting phenols with aldehydes to synthesize phenol resin A,
(B) a step of reacting the phenol resin A and aldehydes dissolved in an organic solvent in the presence of a solid catalyst to synthesize a phenol resin B; and
(C) A step of reacting and / or concentrating the phenol resin B after separating it from the solid catalyst.
(2) The phenol used in the step (a) is a mixture of m-cresol and p-cresol, and the weight ratio of m-cresol and p-cresol is m-cresol / p-cresol = 9. The manufacturing method of the phenol resin for photoresists as described in said (1) which is / 1-2 / 8.
(3) The said phenol resin A is a manufacturing method of the phenol resin for photoresists as described in said (1) or (2) whose weight average molecular weights measured by GPC are 500-15000.
(4) Any of (1) to (3) above, wherein the aldehyde used in the step (b) is formaldehyde, and the addition amount thereof is 0.01 to 1 mol with respect to 1 mol of the phenol resin A. The manufacturing method of the phenol resin for photoresists of description.
(5) The solid catalyst used in the step (b) is insoluble in water and / or an organic solvent and has a function as an acidic catalyst in any one of the above (1) to (4) The manufacturing method of the phenol resin for photoresists of description.
(6) The method for producing a phenol resin for a photoresist according to any one of (1) to (5), wherein the solid catalyst used in the step (b) is an acidic ion exchange resin.
(7) The said acidic ion exchange resin is a manufacturing method of the phenol resin for photoresists as described in said (6) whose usage-amount is 10-500 weight part with respect to 100 weight part of phenol resin A.
(8) The said phenol resin for photoresists is a manufacturing method of the phenol resin for photoresists in any one of said (1) thru | or (7) which satisfy | fills the following characteristics.
(A) The content of the binuclear component is 5% or less.
(A) The weight average molecular weight measured by GPC is 1000-20000.
(9) A photoresist resin composition comprising a photoresist resin, a photosensitive agent, and a solvent obtained by the production method according to any one of (1) to (8) above.

According to the method for producing a phenol resin for a photoresist of the present invention, a phenol resin for a photoresist having a low binuclear component content can be provided at a lower cost and more easily than a conventional production method.
By using the phenol resin for photoresist obtained by this manufacturing method as a photoresist, contamination of the production line can be reduced in the LCD manufacturing process, and an improvement in product yield is expected.
In addition, the production method of the present invention does not remove the dinuclear component contained in the phenolic resin for photoresist, but reduces the content of the binuclear component by further reacting it. It is. As a result, the yield reduction due to the removal of the binuclear component can be substantially eliminated, so that the productivity of the phenol resin for photoresist can be improved and the removed binuclear component is discharged as waste. It is possible to reduce the environmental load.

Hereinafter, the manufacturing method and photoresist composition of the phenol resin for photoresists of this invention are demonstrated.
The manufacturing method of the phenol resin for photoresists of this invention has the following (a)-(c) process, It is characterized by the above-mentioned.
(A) a step of reacting phenols with aldehydes to synthesize phenol resin A,
(B) a step of reacting the phenol resin A and aldehydes dissolved in an organic solvent in the presence of a solid catalyst to synthesize a phenol resin B; and
(C) A step of reacting and / or concentrating the phenol resin B after separating it from the solid catalyst.
The photoresist composition of the present invention is characterized by containing a photoresist resin, a photosensitive agent, and a solvent obtained by the above-described method for producing a photoresist phenol resin of the present invention.

  First, a method for producing a phenol resin for a photoresist according to the present invention (hereinafter sometimes simply referred to as “manufacturing method”) will be described. In the production method of the present invention, first, (a) phenols and aldehydes are reacted to synthesize phenol resin A.

  Although it does not specifically limit as phenols used for the synthesis | combination of the phenol resin A in the said (a) process, For example, cresols, such as phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2 , 4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, xylenols such as 3,5-xylenol, ethyl such as o-ethylphenol, m-ethylphenol, p-ethylphenol In addition to alkylphenols such as phenols, isopropylphenol, butylphenol, and p-tert-butylphenol, polyhydric phenols such as resorcin, catechol, hydroquinone, pyrogallol, and phloroglucin, alkylresorcins, alkylcatechols, and alkylhydrides Alkyl polyhydric phenols such as quinone (any alkyl group, carbon number of 1-4) can be mentioned. These can be used alone or in combination of two or more.

Among the phenols, it is preferable to use m-cresol and p-cresol together.
Moreover, when using together m-cresol and p-cresol, the ratio is not specifically limited, However It is especially preferable to set it as weight ratio (m-cresol / p-cresol) = 9/1-2/8. By using these phenols and adjusting the blending ratio of the two, various characteristics such as sensitivity and heat resistance as a resin for photoresist can be adjusted.
When the ratio of m-cresol is less than the above lower limit value, the sensitivity may decrease, and when it exceeds the above upper limit value, the heat resistance may decrease.

In addition, the aldehydes used for the synthesis of the phenol resin A in the step (a) are not particularly limited. For example, formaldehyde, paraformaldehyde, trioxane, acetaldehyde, propionaldehyde, polyoxymethylene, hexamethylenetetramine, glyoxal, n -Butyraldehyde, caproaldehyde, allyl aldehyde, crotonaldehyde, acrolein, tetraoxymethylene and the like. These can be used alone or in combination of two or more. In addition, aromatic aldehydes such as furfural, benzaldehyde, phenylacetaldehyde, o-tolualdehyde, and salicylaldehyde can also be used as part of the aldehydes.
Among these, it is most preferable to use formaldehyde and paraformaldehyde in view of characteristics of the obtained phenol resin as a photoresist resin.

The phenol resin A obtained in the step (a) is an acidic catalyst in which the phenols (P) and the aldehydes (F ₁ ) are in a molar ratio (F ₁ /P)=0.5 to 1.0. It is preferable that it is obtained by a condensation reaction in the presence.

  Although it does not specifically limit as molecular weight of the phenol resin A, It is preferable that the weight average molecular weight of polystyrene conversion by GPC measurement is 500-15000. Thereby, it can use suitably as base resin used for manufacture of the phenol resin for photoresists of this invention.

  Although it does not specifically limit as an acidic catalyst used when synthesize | combining phenol resin A, For example, inorganic acids, such as hydrochloric acid, a sulfuric acid, phosphoric acid, phosphorous acid, oxalic acid, diethyl sulfuric acid, paratoluenesulfonic acid, organic phosphonic acid, etc. Organic acids, metal salts such as zinc acetate, and the like. These can be used alone or in combination of two or more.

Next, in the production method of the present invention,
(B) The phenol resin A and aldehydes dissolved in an organic solvent are reacted in the presence of a solid catalyst to synthesize a phenol resin B.

First, the phenol resin A obtained in the step (a) is dissolved in an organic solvent.
The organic solvent used here is not particularly limited as long as it can dissolve the phenol resin A. For example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, etc. Ethylene glycol alkyl ethers, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dialkyl ethers such as diethylene glycol dibutyl ether, ethylene glycol alkyl ether acetates such as methyl cellosolve acetate and ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, Propylene glycol Propylene glycol alkyl ether acetates such as rumonoethyl ether acetate and propylene glycol monopropyl ether acetate, ketones such as acetone, methyl ethyl ketone, cyclohexanone and methyl amyl ketone, cyclic ethers such as dioxane, and 2-hydroxypropionic acid Methyl, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl oxyacetate, methyl 2-hydroxy-3-methylbutanoate, 3-methoxybutyl acetate, 3-methyl-3- List esters such as methoxybutyl acetate, ethyl formate, ethyl acetate, butyl acetate, methyl acetoacetate, ethyl acetoacetate, and amides such as N, N'-dimethylformamide It can be. These may be used individually by 1 type, and may be used in mixture of 2 or more types.

  When the phenol resin A is dissolved in an organic solvent to obtain a phenol resin A solution, the concentration is not particularly limited, but the solid content concentration of the phenol resin A is preferably 10 to 60% by weight. Thereby, it can prevent that the handleability of a phenol resin A solution falls by the viscosity increase.

  Although it does not specifically limit as aldehydes used at the said (b) process, The same thing as what is used at the said (a) process can be used conveniently.

The amount of aldehydes used in the step (b) can be arbitrarily set in consideration of the molecular weight of the phenol resin A or the molecular weight of the phenol resin for photoresist obtained by the production method of the present invention. The molar ratio (F ₂ / PR) of aldehydes (F ₂ ) and phenol resin A (PR) is preferably in the range of 0.01 to 1.00.
If the molar ratio exceeds the above upper limit, the resulting phenol resin for photoresist may become excessively high molecular weight or gelled. Moreover, if it is less than the said lower limit, the reduction effect of the binuclear component contained in the phenol resin for photoresists may not be enough.

The solid catalyst used in the step (b) is insoluble in water and / or an organic solvent, can maintain a solid form before and after the reaction, and is a reaction system of the phenol resin A solution and aldehydes. In the above, what functions as an acidic catalyst can be used suitably.
Here, functioning as an acidic catalyst specifically refers to a substance exhibiting Lewis acid or Bronsted / Lowry acid activity, and the exchange of electrons accompanying the release of hydrogen ions from the solid catalyst or adsorption onto the surface of the solid catalyst. It has the property of performing.
Such a solid catalyst is not particularly limited. For example, organic solid acid catalysts such as ion exchange resins, viscous minerals such as acidic clay, activated clay, bentonite and montmorillonite, and inorganic solid acid catalysts such as alumina and silica magnesia. Etc.

Among these, acidic ion exchange resins are suitable when considering the prevention of contamination of the metal component in the phenol resin B and the efficiency of separation and removal from the reaction system in the step (c).
Of the acidic ion exchange resins, styrene-based strongly acidic ion exchange resins are most preferable. Thereby, in addition to the said effect, the reactivity of a binuclear component can be made favorable.
As such a styrene strong acid type ion exchange resin, a commercially available product can be suitably used. Examples of such commercially available products include “Amberlite 15JWET” manufactured by Organo Corporation, “Diaion RCP160H”, “170H” manufactured by Mitsubishi Chemical Industries, Ltd., and the like.

When this acidic ion exchange resin is used, the amount used is not particularly limited, but is preferably 10 to 500 parts by weight with respect to 100 parts by weight of the phenol resin A.
If the amount used is less than the lower limit, the effect of reducing the content of the binuclear component may not be sufficiently obtained. Moreover, when the above upper limit is exceeded, the efficiency at the time of separation and removal from the reaction system in the step (c) may decrease, or the amount of resin adhering to the acidic ion exchange resin surface may increase and loss may increase. is there.

As reaction conditions in the above step (b), the optimum conditions are appropriately selected according to the phenolic monomer species or ratio thereof used in the synthesis of the phenolic resin A, the concentration of the phenolic resin A solution, the type of the solid catalyst, and the like. can do.
In general, the reaction temperature is suitably in the range of 20 to 120 ° C, preferably 60 to 110 ° C. When the reaction temperature is lower than the above lower limit, the reactivity may be lowered and the process may take a long time. On the other hand, if the upper limit is exceeded, the high molecular weight of the phenol resin becomes significant, and it may be difficult to control the molecular weight.
Moreover, there is no restriction | limiting in particular also as reaction time, According to the said conditions including reaction temperature, it can select suitably.

  The reaction form in the step (b) is not particularly limited. For example, a batch system in which a mixture of a phenol resin A solution, a solid catalyst, and aldehydes is charged in a reaction apparatus and reacted by applying stirring or vibration, The solid catalyst can be packed in advance in a column or the like, and the reaction can be carried out by a continuous column system in which the reaction is conducted through a mixture of the phenol resin A solution and aldehydes.

Next, in the production method of the present invention,
(C) The phenol resin B is separated from the solid catalyst, and then reacted and / or concentrated.

  In the step (c), the method for separating the phenol resin B and the solid catalyst is not particularly limited, and can be appropriately selected from methods such as centrifugation, solvent extraction, and filtration using a filter.

In the step (c), the phenol resin B is further reacted and / or concentrated.
Here, the reaction refers to a means for leading to a target molecular weight. Although it does not specifically limit as the method, For example, methods, such as the method of maintaining at 170-240 degreeC, the method of adding a predetermined amount of aldehydes and performing a high molecular weight reaction, can be used. These methods can be appropriately selected and used according to the target molecular weight.
Concentration here means means for removing components such as unreacted aldehydes, organic solvents, and water contained in a solution containing phenol resin B or a resin obtained by further reacting it with the above method. Point to. Although it does not specifically limit as the method, For example, methods, such as simple distillation, vacuum distillation, heat drying, and vacuum drying, can be used.

Although it does not specifically limit as molecular weight of the phenol resin for photoresists obtained by the manufacturing method of this invention, It is preferable that the weight average molecular weight of polystyrene conversion by GPC measurement is 1000-20000. More preferably, it is 1500-15000. Thereby, favorable characteristics can be imparted when used as a photoresist resin.
When the molecular weight is smaller than the lower limit, the heat resistance may be lowered. Moreover, if it is larger than the above upper limit value, the sensitivity may be insufficient.

  The amount of the binuclear component contained in the phenol resin for photoresist obtained by the production method of the present invention is not particularly limited, but is preferably 5% or less, more preferably 4% or less. Thereby, the sublimate in production lines, such as LCD, can be reduced, and the effect which improves productivity can be heightened more.

In the production method of the present invention, the weight average molecular weight and the content of the binuclear component are measured by GPC (gel permeation chromatography) measurement under the following apparatus and conditions.
(1) Equipment and conditions
・ Body: Made by TOSOH ・ HLC-8020
Detector: TOSOH manufactured at a wavelength of 280 nm UV-8011
-Column for analysis: Showa Denko Co., Ltd. * 1 SHODEX KF-802, 1 KF-803, 1 KF-805 were used.
The measurement was performed using tetrahydrofuran as an elution solvent under the conditions of a flow rate of 1.0 ml / min and a column temperature of 40 ° C.
(2) Calculation method The weight average molecular weight was calculated based on a calibration curve prepared using a polystyrene standard material. The content of the binuclear component was calculated from the molecular weight distribution curve by the area ratio (%) of the binuclear component to the entire resin.

The reason why the content of the binuclear component can be reduced in the phenol resin for photoresist obtained by the production method of the present invention is considered as follows.
When a mixture of m / p-cresol and formaldehyde is synthesized by a general method in the presence of an acid catalyst, the reactivity of m-cresol is much higher than that of p-cresol. -A high molecular weight reaction of cresol does not proceed sufficiently, and a phenol resin having a molecular weight distribution with a high content of low-nuclear components, particularly dinuclear components mainly composed of p-cresol, is obtained.
In the conventional method, the dinuclear component is removed from this state. However, in the production method of the present invention, the low nuclei component mainly composed of low-reactivity p-cresol is further reacted to walk into the resin. And the content of the binuclear component could be reduced.

In addition, even if aldehydes are added to a resin once made into a resin and reacted, a high molecular weight component rich in reactivity preferentially undergoes a condensation reaction, and the low-nuclear component has substantially no change. There is a trend toward higher molecular weight.
On the other hand, the production method of the present invention is characterized in that a predetermined amount of the solid catalyst is preferably used. Thereby, it can be set as reaction conditions that the catalyst amount in a reaction system is large excess.
As a result, it is considered that sufficient reactivity can be imparted even to a low nuclear component having relatively low reactivity, and the content of the binuclear component can be further reduced.
Such a catalyst-excess reaction system can be formed by a normal acidic catalyst, but it is difficult to separate the catalyst components after the reaction, which is not practical. In the production method of the present invention, since a solid catalyst that can be easily separated is used, it is useful as an industrial production method.

In the production method of the present invention, it is preferable to use a styrene strongly acidic ion exchange resin as the solid catalyst. Thereby, the effect of reducing the content of low-nuclear components such as dinuclear components can be further enhanced.
Such a styrenic strongly acidic ion exchange resin has a large number of microporous (pores) and exhibits catalytic activity even in the pores. Thereby, the reaction opportunity of the low molecular weight component with a small molecular size increases relatively, and it is thought that it can react preferentially.

  Next, the photoresist composition of the present invention (hereinafter sometimes simply referred to as “composition”) will be described. The composition of the present invention comprises a photoresist resin obtained by the production method of the present invention, a photosensitive agent, and a solvent.

Although it does not specifically limit as a photosensitizer used for the composition of this invention, For example, a quinonediazide group containing compound can be used conveniently. Examples of the quinonediazide group-containing compound include:
(1) 2,3,4-trihydroxybenzophenone, 2,4,4′-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone, 2,3,6-trihydroxybenzophenone, 2,3,4 Trihydroxy-2'-methylbenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2,3', 4,4 ', 6-pentahydroxy Benzophenone, 2,2 ′, 3,4,4′-pentahydroxybenzophenone, 2,2 ′, 3,4,5-pentahydroxybenzophenone, 2,3 ′, 4,4 ′, 5 ′, 6-hexahydroxy Polyhydroxybenzophenones such as benzophenone, 2,3,3 ′, 4,4 ′, 5′-hexahydroxybenzophenone,

(2) Bis (2,4-dihydroxyphenyl) methane, bis (2,3,4-trihydroxyphenyl) methane, 2- (4-hydroxyphenyl) -2- (4′-hydroxyphenyl) propane, 2- (2,4-dihydroxyphenyl) -2- (2 ′, 4′-dihydroxyphenyl) propane, 2- (2,3,4-trihydroxyphenyl) -2- (2 ′, 3 ′, 4′-tri Hydroxyphenyl) propane, 4,4 ′-{1- [4- [2- (4-hydroxyphenyl) -2-propyl] phenyl] ethylidene} bisphenol, 3,3′-dimethyl- {1- [4- [ Bis [(poly) hydroxyphenyl] alkanes such as 2- (3-methyl-4-hydroxyphenyl) -2-propyl] phenyl] ethylidene} bisphenol,

(3) Tris (4-hydroxyphenyl) methane, bis (4-hydroxy-3,5-dimethylphenyl) -4-hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -4-hydroxyphenyl Methane, bis (4-hydroxy-3,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-2, Tris (hydroxyphenyl) methanes such as 5-dimethylphenyl) -3,4-dihydroxyphenylmethane and bis (4-hydroxy-3,5-dimethylphenyl) -3,4-dihydroxyphenylmethane or methyl-substituted products thereof,

(4) Bis (3-cyclohexyl-4-hydroxyphenyl) -3-hydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxyphenyl) -2-hydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxyphenyl) -4-hydroxyphenylmethane, bis (5-cyclohexyl-4-hydroxy-2-methylphenyl) -2-hydroxyphenylmethane, bis (5-cyclohexyl-4-hydroxy-2-methylphenyl) -3-hydroxyphenylmethane Bis (5-cyclohexyl-4-hydroxy-2-methylphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl-2-hydroxyphenyl) -3-hydroxyphenylmethane, bis (5-cyclohexyl-4-hydroxy -3-Me Ruphenyl) -4-hydroxyphenylmethane, bis (5-cyclohexyl-4-hydroxy-3-methylphenyl) -3-hydroxyphenylmethane, bis (5-cyclohexyl-4-hydroxy-3-methylphenyl) -2-hydroxy Phenylmethane, bis (3-cyclohexyl-2-hydroxyphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl-2-hydroxyphenyl) -2-hydroxyphenylmethane, bis (5-cyclohexyl-2-hydroxy-4) Bis (cyclohexylhydroxyphenyl) (hydroxyphenyl) methanes, such as -methylphenyl) -2-hydroxyphenylmethane, bis (5-cyclohexyl-2-hydroxy-4-methylphenyl) -4-hydroxyphenylmethane or A complete ester compound of a methyl-substituted product and the like and a quinonediazide group-containing sulfonic acid such as naphthoquinone-1,2-diazide-5-sulfonic acid or naphthoquinone-1,2-diazide-4-sulfonic acid, orthoanthraquinonediazidesulfonic acid, Partial ester compounds, amidates or partial amidates,
And so on.

  Here, the quinonediazide group-containing compound may be contained singly or in combination of two or more.

Although it does not specifically limit as a compounding quantity of a quinonediazide group containing compound, Usually, it is 5-100 weight part with respect to 100 weight part of phenol resins for photoresists, Preferably it is 10-50 weight part.
If the blending amount is less than the lower limit, an image faithful to the pattern cannot be obtained, and transferability may be deteriorated. On the other hand, when the upper limit is exceeded, the sensitivity of the photoresist is lowered.

  Further, the solvent is not particularly limited. For example, ethylene glycol alkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol diethylene glycol Diethylene glycol dialkyl ethers such as propyl ether and diethylene glycol dibutyl ether, ethylene glycol alkyl ether acetates such as methyl cellosolve acetate and ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol model Propylene glycol alkyl ether acetates such as propyl ether acetate, ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl amyl ketone, cyclic ethers such as dioxane, and methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, Ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl oxyacetate, methyl 2-hydroxy-3-methylbutanoate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, ethyl formate, ethyl acetate And esters such as butyl acetate, methyl acetoacetate and ethyl acetoacetate. These may be used individually by 1 type, and may be used in mixture of 2 or more types.

  Although the usage-amount of this solvent is not specifically limited, It is preferable that the solid content concentration of a composition shall be 30 to 65 weight%. When the solid content concentration exceeds 65% by weight, the fluidity of the composition is lowered, so that handling becomes difficult, and a uniform resist film is hardly obtained by the spin coating method.

  In addition to the components described above, the composition of the present invention may contain various additives such as surfactants, adhesion improvers, dissolution accelerators, fillers, pigments and the like as necessary. It can also be added.

Next, a method for preparing the composition of the present invention will be described.
The method for preparing the composition of the present invention is not particularly limited, but can be prepared by dissolving a phenol resin for photoresist, a photosensitizer, and other various additives in a solvent by stirring and mixing in a usual manner. .
Moreover, when adding a filler and a pigment, the method of disperse | distributing and mixing using dispersers, such as a dissolver, a homogenizer, and a 3 roll mill, can be applied.
Furthermore, after preparing the composition, it may be further filtered using a mesh filter, a membrane filter or the like, if necessary.

  By exposing the composition thus obtained through a mask, a structural change occurs in the composition in the exposed area, and the solubility in an alkali developer is promoted. On the other hand, low solubility in an alkaline developer is maintained in the non-exposed area. A resist function is imparted by the difference in solubility generated in this way.

Hereinafter, the present invention will be described with reference to examples. However, the present invention is not limited to these examples. In the examples and comparative examples, “parts” indicates “parts by weight” and “%” indicates “% by weight”.
The content (%) of the binuclear component is based on the area ratio obtained by GPC measurement.

1. Synthesis of phenol resin A (1) Synthesis example 1
Phenol in which m-cresol and p-cresol were mixed in a molar ratio (m-cresol: p-cresol) = 6: 4 in a 3 L four-necked flask equipped with a stirrer, a thermometer, and a heat exchanger A 465 part of 37% formalin aqueous solution and 2 parts of oxalic acid were added to 1000 parts of a kind and reacted for 4 hours under reflux. Thereafter, dehydration was carried out under normal pressure to an internal temperature of 170 ° C., and dehydration / demonomerization was further carried out to 200 ° C. under a reduced pressure of 70 torr. Obtained. This is designated as phenol resin A1.

(2) Synthesis example 2
Phenol in which m-cresol and p-cresol were mixed in a molar ratio (m-cresol: p-cresol) = 3: 7 in a 3 L four-necked flask equipped with a stirrer, a thermometer, and a heat exchanger. 435 parts of a 37% formalin aqueous solution and 2 parts of oxalic acid were added to 1000 parts of a kind and reacted for 4 hours under reflux. Thereafter, dehydration was carried out under normal pressure up to an internal temperature of 170 ° C., and dehydration / demonomerization was further carried out up to 200 ° C. under a reduced pressure of 70 torr. Obtained. This is designated as phenol resin A2.

(3) Synthesis example 3
Phenol in which m-cresol and p-cresol were mixed in a molar ratio (m-cresol: p-cresol) = 8: 2 in a 3 L four-necked flask equipped with a stirrer, a thermometer, and a heat exchanger. A 443 part of 37% formalin aqueous solution and 2 parts of oxalic acid were added to 1000 parts of a kind and reacted for 4 hours under reflux. Thereafter, dehydration was performed under normal pressure to an internal temperature of 170 ° C., and dehydration / demonomerization was further performed to 200 ° C. under a reduced pressure of 70 torr. Obtained. This is designated as phenol resin A3.

(4) Synthesis example 4
Phenol in which m-cresol and p-cresol were mixed in a molar ratio (m-cresol: p-cresol) = 6: 4 in a 3 L four-necked flask equipped with a stirrer, a thermometer, and a heat exchanger To 1000 parts of the compound, 330 parts of a 37% formalin aqueous solution, 497 parts of salicylaldehyde, and 2 parts of PTSA (paratoluenesulfonic acid) were charged and reacted under reflux for 6 hours. Thereafter, dehydration was carried out under normal pressure to an internal temperature of 170 ° C., and dehydration / demonomerization was carried out to 200 ° C. under a reduced pressure of 70 torr. Obtained. This is designated as phenol resin A4.

(5) Synthesis example 5
Phenol in which phenol and 3,5-xylenol are mixed in a molar ratio (phenol: 3,5-xylenol) = 7: 3 in a 3 L four-necked flask equipped with a stirrer, a thermometer, and a heat exchanger 7000 parts of 37% formalin aqueous solution and 2 parts of oxalic acid were added to 1000 parts of a kind and reacted for 4 hours under reflux. Thereafter, dehydration was performed under normal pressure to an internal temperature of 170 ° C., and dehydration / demonomerization was further performed to 200 ° C. under a reduced pressure of 70 torr to obtain 920 parts of a novolak type phenol resin having a weight average molecular weight of 7900 and a binuclear content of 10%. Obtained. This is designated as phenol resin A5.

2. Synthesis of phenolic resin for photoresist (1) Example 1
In a 1 L four-necked flask equipped with a stirrer, a thermometer, and a heat exchanger, 100 parts of phenol resin A1 and 400 parts of propylene glycol monomethyl ether acetate (hereinafter referred to as “PGMEA”) were dissolved. 7 parts of 37% formaldehyde [molar ratio (F ₂ /PR)=0.104] and 50 parts of styrene strong acid ion exchange resin (manufactured by Organo Corporation, “Amberlite 15JWET”) were added thereto at 90 ° C. for 12 hours. The solution after the reaction was filtered and separated from the ion exchange resin, and the filtrate was dried with a vacuum dryer to obtain 95 parts of a phenol resin for a photoresist, the weight average molecular weight measured by GPC was 6500, 2 The nucleus content was 3.2%.

(2) Example 2
In the same apparatus as in Example 1, 100 parts of phenol resin A1 and 400 parts of PGMEA were added and dissolved. To this, 35 parts of 37% formaldehyde [molar ratio (F ₂ /PR)=0.518] and 400 parts of zeolite (manufactured by Tosoh Corporation, high silica zeolite “HSZ-690HOA”) are added and reacted at 90 ° C. for 24 hours. It was. The solution after the reaction was filtered to separate from the ion exchange resin, and the filtrate was dried with a vacuum dryer to obtain 90 parts of phenol resin for photoresist b. The weight average molecular weight measured by GPC was 7000, and the dinuclear content was 4.8%.

(3) Example 3
In the same apparatus as in Example 1, 100 parts of phenol resin A1 and 400 parts of dimethylformamide were added and dissolved. 7 parts of 37% formaldehyde [molar ratio (F ₂ /PR)=0.104] and 100 parts of a styrenic strongly acidic ion exchange resin (manufactured by Organo, “Amberlite 15JWET”) were added thereto, and the mixture was added at 90 ° C. with 8 parts. Reacted for hours. The solution after the reaction was filtered and separated from the ion exchange resin, and the filtrate was dried with a vacuum dryer to obtain 95 parts of a phenol resin for photoresist c. The weight average molecular weight measured by GPC was 6700, and the binuclear content was 3.6%.

(4) Example 4
In the same apparatus as in Example 1, 2100 parts of phenol resin A and 400 parts of PGMEA were added and dissolved. 7 parts of 37% formaldehyde [molar ratio (F ₂ /PR)=0.104] and 50 parts of a styrenic strongly acidic ion exchange resin (manufactured by Organo Corporation, “Amberlite 15JWET”) were added thereto, and 12 parts at 90 ° C. Reacted for hours. The solution after the reaction was filtered to separate from the ion exchange resin, and the filtrate was dried with a vacuum dryer to obtain 95 parts of phenol resin for photoresist. The weight average molecular weight measured by GPC was 4800, and the binuclear content was 3.2%.

(5) Example 5
In the same apparatus as in Example 1, 3100 parts of phenol resin A and 400 parts of PGMEA were added and dissolved. To this, 15 parts of 37% formaldehyde [molar ratio (F ₂ /PR)=0.222] and 50 parts of a styrenic strongly acidic ion exchange resin (manufactured by Organo Corporation, “Amberlite 15JWET”) were added. Reacted for hours. The solution after the reaction was separated from the ion exchange resin by filtration, and further 15 parts of 37% formaldehyde and 2 parts of oxalic acid were added and reacted at 100 ° C. for 3 hours. Thereafter, the product was dried by a vacuum dryer to obtain 95 parts of phenol resin for photoresist e. The weight average molecular weight measured by GPC was 3200, and the binuclear content was 3.7%.

(6) Example 6
In the same apparatus as in Example 1, 4100 parts of phenol resin A and 400 parts of PGMEA were added and dissolved. 7 parts of 37% formaldehyde [molar ratio (F ₂ /PR)=0.104] and 50 parts of a styrenic strongly acidic ion exchange resin (manufactured by Organo Corporation, “Amberlite 15JWET”) were added thereto, and 12 parts at 90 ° C. Reacted for hours. The solution after the reaction was filtered to separate from the ion exchange resin, and the filtrate was dried with a vacuum dryer to obtain f95 parts of a phenol resin for photoresist. The weight average molecular weight measured by GPC was 8300, and the dinuclear content was 3.8%.

(7) Example 7
In the same apparatus as in Example 1, 5100 parts of phenol resin A and 400 parts of PGMEA were added and dissolved. 7 parts of 37% formaldehyde [molar ratio (F ₂ /PR)=0.099] and 50 parts of a styrenic strongly acidic ion exchange resin (manufactured by Organo Corporation, “Amberlite 15JWET”) were added thereto, and 12 parts at 90 ° C. Reacted for hours. The solution after the reaction was separated from the ion exchange resin by filtration, and further 3 parts of 37% formaldehyde and 2 parts of oxalic acid were added and reacted at 100 ° C. for 3 hours. Then, the product was dried with a vacuum dryer to obtain 95 parts of phenol resin for photoresist. The weight average molecular weight measured by GPC was 9400, and the content of the binuclear component was 2.7%.

3. Preparation of photoresist composition (1) Example 8
After dissolving 70 parts of phenol resin a for photoresist obtained in Example 1 and 15 parts of 2,3,4-trihydroxybenzophenone ester of naphthoquinone 1,2-diazide-5-sulfonic acid in 150 parts of PGMEA, Filtration was performed using a membrane filter having a pore diameter of 1.0 μm to prepare a positive photoresist composition.

(2) Example 9
A composition was prepared in the same manner as in Example 8 except that the photoresist phenol resin b obtained in Example 2 was used instead of the phenol resin a for photoresist.

(3) Example 10
A composition was prepared in the same manner as in Example 8, except that the photoresist phenol resin c obtained in Example 3 was used instead of the phenol resin a for photoresist.

(4) Example 11
A composition was prepared in the same manner as in Example 8, except that the photoresist phenol resin d obtained in Example 4 was used instead of the phenol resin a for photoresist.

(5) Example 12
A composition was prepared in the same manner as in Example 8 except that the photoresist phenol resin e obtained in Example 5 was used instead of the phenol resin a for photoresist.

(6) Example 13
A composition was prepared in the same manner as in Example 8, except that the photoresist phenol resin f obtained in Example 6 was used instead of the photoresist phenol resin a.

(7) Example 14
A composition was prepared in the same manner as in Example 6 except that instead of the phenol resin a for photoresist a, the phenol resin g for photoresist obtained in Example 7 was used.

(8) Comparative Example 1
A composition was prepared in the same manner as in Example 8 except that the photoresist phenol resin A1 obtained in Synthesis Example 1 was used instead of the photoresist phenol resin a.

(9) Comparative Example 2
A composition was prepared in the same manner as in Example 8 except that the phenol resin A2 for photoresist obtained in Synthesis Example 2 was used instead of the phenol resin A for photoresist.

  The characteristics evaluation shown below was performed using the photoresist compositions obtained in Examples 8 to 14 and Comparative Examples 1 and 2. The results are shown in Table 1.

4). Photoresist Characteristic Evaluation Method (1) Sublimation Property A photoresist composition was applied on a 3 inch silicon wafer with a spin coater to a thickness of about 1 μm and dried on a 110 ° C. hot plate for 100 seconds. During this drying, the silicon wafer was covered with a petri dish to collect the sublimate. This operation was performed for 10 sheets, and the weight of the substance adhering to the petri dish was measured.
(2) Film reduction rate The photoresist composition was applied to a thickness of about 1 μm on a 3-inch silicon wafer by a spin coater and dried on a hot plate at 110 ° C. for 100 seconds. The wafer was immersed in a developing solution (2.38% tetramethylammonium hydroxide aqueous solution) for 60 seconds, washed with water, and dried on a hot plate at 110 ° C. for 100 seconds. The reduction amount of the film thickness when immersed in the developer is expressed as a percentage with respect to the film thickness before being immersed in the developer, and is defined as the film reduction rate.
(3) Sensitivity The photoresist composition was applied to a 3-inch silicon wafer with a spin coater to a thickness of about 1 μm and dried on a 110 ° C. hot plate for 100 seconds. Then repeated test chart mask on the silicon wafer ^was irradiated ^{50mJ / cm 2, 100mJ / cm} 2, 150mJ / cm 2, 200mJ / cm 2, 250mJ / cm 2 of ultraviolet light, respectively, developer (2.38% Development was performed for 90 seconds using an aqueous tetramethylammonium hydroxide solution. The obtained pattern was evaluated according to the following criteria by observing the pattern shape with a scanning electron microscope.
○: 50~150mJ / cm ² image can be formed by △: 200~250mJ / cm ² image can be formed by ×: 250 mJ / cm can not image formation even ²

Examples 1 to 7 are phenolic resins for photoresist obtained by the production method of the present invention.
Examples 8 to 14 are compositions using this photoresist resin. As shown in Table 1, each of Examples 8 to 14 is substantially different in film reduction rate and sensitivity as compared with Comparative Examples 1 and 2 which are compositions using a phenol resin synthesized by a one-step reaction. The amount of sublimation could be reduced.

  When used as a photoresist composition, the phenol resin for photoresist obtained by the production method of the present invention can reduce the amount of sublimation without substantially reducing other properties, and can be used on a production line. It is possible to reduce contamination and improve productivity. Therefore, the present invention is useful as a method for producing a phenol resin for a photoresist, which is applied to a photoresist composition suitable for a process aimed at producing an LCD.

Claims (9)

The manufacturing method of the phenol resin for photoresists characterized by having the following (a)-(c) process.
(A) a step of reacting phenols with aldehydes to synthesize phenol resin A,
(B) a step of reacting the phenol resin A and aldehydes dissolved in an organic solvent in the presence of a solid catalyst to synthesize a phenol resin B; and
(C) A step of reacting and / or concentrating the phenol resin B after separating it from the solid catalyst. The phenols used in the step (a) are a mixture of m-cresol and p-cresol, and the weight ratio of m-cresol and p-cresol is m-cresol / p-cresol = 9/1 to 1. The method for producing a phenol resin for a photoresist according to claim 1, which is 2/8. The method for producing a phenol resin for a photoresist according to claim 1 or 2, wherein the phenol resin A has a weight average molecular weight of 500 to 15000 measured by GPC. The aldehyde used in the step (b) is formaldehyde, and the addition amount thereof is 0.01 to 1 mol with respect to 1 mol of the phenol resin A. A method for producing a phenolic resin. The phenol for photoresist according to any one of claims 1 to 4, wherein the solid catalyst used in the step (b) is insoluble in water and / or an organic solvent and has a function as an acidic catalyst. Manufacturing method of resin. The method for producing a phenol resin for a photoresist according to any one of claims 1 to 5, wherein the solid catalyst used in the step (b) is an acidic ion exchange resin. The method for producing a phenol resin for a photoresist according to claim 6, wherein the amount of the acidic ion exchange resin used is 10 to 500 parts by weight with respect to 100 parts by weight of the phenol resin A. The method for producing a phenol resin for a photoresist according to any one of claims 1 to 7, wherein the phenol resin for a photoresist satisfies the following characteristics.
(A) The content of the binuclear component is 5% or less.
(A) The weight average molecular weight measured by GPC is 1000-20000. A photoresist resin composition comprising a photoresist resin obtained by the production method according to claim 1, a photosensitive agent, and a solvent.