JP2001139806A - Heat-resistant photosensitive resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-resistant photosensitive resin compositions which can be pattern-processed in a low exposure and have a small shrink after pattern processing. SOLUTION: The heat-resistant photosensitive resin compositions comprise (a) a polymer having a structural unit represented by the formula, wherein R1 is >=2C di- to octa-valent organic group; R2 is >=2C di- to octa-valent organic group; R3; R4, R5, and R6 re each a hydrogen atom, 1-20C monovalent alkyl group or a monovalent organic group having one to three unsaturated bonds, provided that all R5s and R6s are not simultaneously hydrogen atoms; n is an integer of 3-100,000; p and q are each an integer of 0-4; and r and s are each an integer of 0-2, (b) a photosensitizer, and (c) a solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant photosensitive resin composition capable of forming a pattern usable for an interlayer insulating film, a buffer coat film, an .alpha.

[0002]

2. Description of the Related Art Hitherto, heat-resistant resins such as polyimide have been widely used as surface protective films and interlayer insulating films of semiconductor devices. Above all, the photosensitive resin composition itself capable of pattern processing has a pattern accuracy applicable to the pattern formation of the passivation film, so first, pattern processing of the photosensitive resin composition on the passivation film before pattern formation, A method of performing curing and then dry-etching the underlying passivation film using this pattern as a mask has been studied (batch-opening method). According to this method, the process required for forming the pattern of the passivation film can be omitted, leading to cost reduction.

On the other hand, the photosensitive resin composition is usually applied to a substrate in a solution state, dried, and irradiated with actinic rays through a mask. There is a negative-type photosensitive resin composition in which the exposed portion remains by development, and a positive-type photosensitive resin composition in which the exposed portion is dissolved by development with an alkaline aqueous solution. To which a dimerizable or polymerizable carbon-carbon double bond and an amino group or a quaternary salt thereof are added (Japanese Patent Publication No. 59-5282)
No. 2, JP-A No. 3-177455, and as a positive type, a composition represented by a mixture of an polyimide having a phenolic hydroxyl group and an o-quinonediazide compound (JP-A-3-177455) is known.

However, these compositions use N-methyl-2-pyrrolidone or the like having a high polarity as a solvent and a large interaction force with a polymer as a solvent, and when the pattern is actually formed, the solvent is removed. Difficult, 80 ℃
In prebaking at a temperature of from 120 to 120 ° C, more than 20% of the solvent remains,
As a result, there have been problems such as a decrease in sensitivity and a large shrinkage due to a subsequent heat treatment.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a heat-resistant photosensitive resin composition which can be patterned at a low exposure dose and has a small shrinkage after the pattern processing.

[0006]

The present invention comprises (a) a polymer having a structural unit represented by the general formula (1);
A heat-resistant photosensitive resin composition comprising a photosensitive agent and a solvent (c), wherein the viscosity of the solution when the concentration of the polymer represented by the general formula (1) is 20% by weight is determined by the solvent N- A heat-resistant photosensitive resin composition having a viscosity of 1.3 to 7 times the viscosity of a solution when the polymer represented by the general formula (1) has the same concentration with only methyl-pyrrolidone. Wherein the solvent is a heat-resistant photosensitive resin composition wherein one or more solvents are used.

[0007]

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(R ¹ is a divalent to octavalent organic group having at least 2 or more carbon atoms, R ² is a divalent to octavalent organic group having at least 2 or more carbon atoms, R ³ ,
R ⁴ , R ⁵ and R ^{6 each} represent hydrogen or a monovalent alkyl group having 1 to 20 carbon atoms and a monovalent organic group having 1 to 3 unsaturated bonds. Further, R ⁵ and R ⁶ are not all hydrogen. n is an integer from 3 to 100,000, and p and q are integers from 0 to 4. r and s are 0
And an integer from 2 to 2. )

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a polymer represented by the general formula (1) is heated or heated by a suitable catalyst.
It can be a polymer having an imide ring, an oxazole ring, or another cyclic structure. By having a ring structure,
Heat resistance and solvent resistance are dramatically improved.

The polymer having the structural unit represented by the general formula (1) as a main component preferably has a hydroxyl group. At this time, p and q in the general formula (1) are in a condition of p + q> 0. In this case, due to the presence of the hydroxyl group, the solubility in an aqueous alkali solution becomes better than that of a polyamic acid having no hydroxyl group. In particular, among the hydroxyl groups, phenolic hydroxyl groups are preferable from the viewpoint of solubility in an aqueous alkaline solution. In addition, since the presence or absence of a hydroxyl group can be considered depending on the type of solution used for development, for example, when a polymer represented by the general formula (1) is used as a negative type by alkali development, a hydroxyl group is used even in the negative type. May be.

In the general formula (1), the residue constituting R ¹ represents a structural component of an acid, and the acid component contains an aromatic ring and has 1 to 4 hydroxyl groups. 2-6 carbon atoms
A trivalent to octavalent group of 0 is preferred. When R ¹ does not contain a hydroxyl group, the R ² component desirably contains 1 to 4 hydroxyl groups. Further, the hydroxyl group is preferably located at a position adjacent to the amide bond. Examples of such a structure include those having the following structures, but the present invention is not limited thereto.

[0012]

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(R represents hydrogen or a monovalent alkyl group having 1 to 20 carbon atoms and a monovalent organic group having 1 to 3 unsaturated bonds.)

As the residue containing R ¹ , a tetracarboxylic acid, tricarboxylic acid, or dicarboxylic acid having no hydroxyl group can be used. Examples of these include:
Aromatic tetracarboxylic acids such as pyromellitic acid, benzophenonetetracarboxylic acid, biphenyltetracarboxylic acid, diphenylethertetracarboxylic acid, diphenylsulfonetetracarboxylic acid, and diester compounds in which two carboxyl groups are converted to methyl groups or ethyl groups, butanetetra Aliphatic tetracarboxylic acids such as carboxylic acid and cyclopentanetetracarboxylic acid, diester compounds in which two carboxyl groups are converted to methyl or ethyl groups, and aromatic tricarboxylic acids such as trimellitic acid, trimesic acid, and naphthalene tricarboxylic acid Can be mentioned.

In the general formula (1), the residue constituting R ² represents a structural component of diamine. Among them, a preferable example of R ² is one having an aromatic group and having 1 to 4 hydroxyl groups from the viewpoint of heat resistance of the obtained polymer. When R ² does not contain a hydroxyl group, the R ¹ component desirably contains 1 to 4 hydroxyl groups. Further, the hydroxyl group is preferably located at a position adjacent to the amide bond.

Specific examples include compounds such as bis (aminohydroxyphenyl) hexafluoropropane, diaminodihydroxypyrimidine, diaminodihydroxypyridine, hydroxydiaminopyrimidine, diaminophenol and dihydroxybenzene, and those having the structures shown below. Can be

[0017]

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(J and k are integers from 0 to 2, j + k>
0).

Further, a diamine containing no hydroxyl group can be used as the residue containing R ² in the general formula (1).
Such examples include phenylenediamine, diaminodiphenyl ether, aminophenoxybenzene, diaminodiphenylmethane, diaminodiphenylsulfone, bis (trifluoromethyl) benzidine, bis (aminophenoxyphenyl) propane, bis (aminophenoxyphenyl) sulfone, and aromatics thereof. Aliphatic cyclohexyldiamine, methylenebiscyclohexylamine, and the like, such as compounds in which an aromatic ring is substituted with an alkyl group or a halogen atom, may be mentioned. These diamine compounds are used alone or in combination of two or more. They are,
It is preferable to use not more than 40 mol% of the diamine component. 40
If the copolymerization is at least mol%, the heat resistance of the obtained polymer will be reduced.

When neither R ¹ nor R ^{2 in} the general formula (1) has a hydroxyl group, R ¹ may be pyromellitic acid, benzophenonetetracarboxylic acid, biphenyltetracarboxylic acid, diphenylethertetracarboxylic acid,
Aromatic tetracarboxylic acids such as diphenylsulfonetetracarboxylic acid, and diester compounds of two carboxyl groups thereof by a methyl group or an ethyl group, an organic group having at least one carbon-carbon unsaturated bond, butanetetracarboxylic acid, cyclopentane Aliphatic tetracarboxylic acids such as tetracarboxylic acids, diester compounds of two carboxyl groups thereof, a methyl group or an ethyl group, an organic group having at least one carbon-carbon unsaturated bond, trimellitic acid, trimesic acid, naphthalene An aromatic tricarboxylic acid such as a tricarboxylic acid, in which one carboxyl group has at least one methyl group or ethyl group and at least one carbon-carbon unsaturated bond.
An ester compound based on one or more organic groups can be used. As the R ¹ component, these compounds are used alone or as a mixture of two or more.

As the R ² component, phenylenediamine,
Diaminodiphenyl ether, aminophenoxybenzene, diaminodiphenylmethane, diaminodiphenylsulfone, bis (trifluoromethyl) benzidine, bis (aminophenoxyphenyl) propane, bis (aminophenoxyphenyl) sulfone or their aromatic ring with an alkyl group or a halogen atom Such as substituted compounds,
Aliphatic cyclohexyldiamine, methylenebiscyclohexylamine and the like can be mentioned. These diamine compounds are used alone or in combination of two or more.

For the purpose of improving the adhesion to the substrate, a diamine compound having a siloxane structure may be used as long as the heat resistance is not reduced. Examples of the diamine compound having a siloxane structure include bis (3-aminopropyl) tetramethyldisiloxane, bis (3-aminopropyl) tetraphenyldisiloxane, and bis (4
-Aminophenyl) tetramethyldisiloxane and the like are used.

When used as a positive type, R ³ , R ⁴ , R ⁵ and R ⁶ in the general formula (1) are preferably hydrogen or an organic group having 1 to 20 carbon atoms. If each of R ³ , R ⁴ , R ⁵ and R ⁶ has more than 20 carbon atoms, it will not be dissolved in an aqueous alkaline solution. From the stability of the obtained photosensitive resin solution, R ³ , R ⁴ ,
R ⁵ and R ⁶ are preferably organic groups, but are preferably hydrogen in view of the solubility of the aqueous alkali solution. These R ³ , R ⁴ , R ⁵ , R ⁶
By controlling the amounts of hydrogen and organic groups, the dissolution rate in an aqueous alkali solution changes, so that a photosensitive resin composition having an appropriate dissolution rate can be obtained by this adjustment. From this, it is preferable that the carboxyl group in the polymer is contained in an amount of 0.02 mmol or more and 2 mmol or less in 1 g of the polymer. More preferably, it is 0.05 mmol or more and 1.5 mmol or less. If it is less than 0.02 mmol, the solubility in the developing solution becomes too small, and 2 mm
When it is larger than ol, the difference in the dissolution rate between the exposed part and the unexposed part is difficult to be obtained. p and q each represent an integer from 0 to 4.
When p is 5 or more, the properties of the obtained heat-resistant resin film deteriorate.

When a negative composition is obtained, R ³ , R ⁴ , R
^5, R ⁶ it is desirable to a group having a component in the unsaturated bond has at least one. In addition, compounds having an unsaturated bond such as ethylene glycol dimethacrylate, trimethacryl glyceroid, trimethylolpropane triacrylate, and other urethane acrylate compounds can also be added.

It is also possible to control the amount of residual carboxyl groups by imidizing some of the carboxyl groups. As the imidation method, a known method may be used as long as the imidization can be performed. The imidation ratio at this time is preferably 1% or more and 50% or less. If the imidation ratio exceeds 50%, the absorption of the polymer by actinic radiation used for exposure increases, and the sensitivity decreases.

It is desirable that the polymer represented by the general formula (1) is as transparent as possible to the actinic radiation to be exposed. Therefore, the absorbance of the polymer at 365 nm is preferably 0.1 or less per 1 μm. It is more preferably 0.08 or less. It is 365 when it exceeds 0.1
The sensitivity to exposure to nm actinic radiation is reduced.

The positive photosensitive resin composition of the present invention may be composed of only the structural unit represented by the general formula (1), or may be a copolymer or a blend with another structural unit. There may be. In this case, it is preferable that the content of the structural unit represented by the general formula (1) is 90 mol% or more.
The type and amount of the structural unit used in the copolymerization or blending are preferably selected within a range that does not impair the heat resistance of the polyimide-based polymer obtained by the final heat-treated film.

The polymer having a structural unit represented by the general formula (1) of the present invention as a main component is synthesized by a known method. For example, a method of reacting a tetracarboxylic dianhydride with a diamine compound at a low temperature (CE Sroog et al.,
Journal Polymer Science,
Part A-3, 1373 (1965)).

The polymer represented by the general formula (1) has a carboxyl group concentration by subjecting the carboxyl group in the polymer obtained by the above method to esterification with an acetal or ketal compound, a vinyl ether compound, or a vinyl ether compound with an acid catalyst. Can be adjusted.

Specific examples of such acetal, ketal and vinyl ether compound include N, N-dimethylformamide dimethyl acetal, N, N-dimethylformamide diethyl acetal, N, N-dimethylformamide dipropyl acetal, N, N- Dimethylformamide dibutyl acetal, N, N-dimethylformamide dibenzyl acetal, N, N-dimethylformamide bis [2- (trimethylsilyl) ethyl] acetal, N, N-dimethylacetamide diethylacetal, trimethyl orthoformate, triethyl orthoformate, ortho Trimethyl acetate, triethyl orthoacetate, trimethyl orthobutyrate, triethyl orthobutyrate, trimethyl orthobenzoate, triethyl orthobenzoate, 1,3-dimethylimidozolidino Dialkyl acetal, ethylene carbonate dialkyl acetal, propylene carbonate dialkyl acetal, .gamma.-butyrolactone dialkyl acetals, methyl vinyl ether, ethyl vinyl ether, n
-Propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, cyclohexyl vinyl ether, and the like, but are not limited thereto.

As the photosensitive agent used in the present invention, benzophenone, Michler's ketone, 4,4'-bisdiethylaminobenzophenone,
Phenanthrenequinone, benzoin ethyl ether, benzoin phenyl ether, benzyl methyl ketal,
2- (o-chlorophenyl) -4,5-diphenylimidazole, 4,4-bis (diethylamino) chalcone,
2,6-bis (4'-diethylaminobenzylidene)
Cyclopentanone, benzimidazole, mercaptobenzothiazole and the like can be mentioned.

In the case of the positive type in which unexposed portions remain, naphthoquinonediazidosulfonic acid ester, diazonium salt, diazoquinonesulfonic acid amide, diazoquinonesulfonic acid ester, diazoquinonesulfonic acid salt, nitrobenzyl ester, onium salt, halide, Compounds which decompose upon irradiation with light, such as halogenated isocyanate, halogenated triazine, bisarylsulfonyldiazomethane and disulfone, to generate an acid can be used as the photosensitive component. In particular, an o-quinonediazide compound is desirable because it has an effect of suppressing the water solubility of an unexposed portion. Such compounds include 1,2-benzoquinone-2-azido-4
Sulfonic acid esters or sulfonic acid amides, 1,2-
Examples include naphthoquinone-2-diazide-5-sulfonic acid ester or sulfonic acid amide, and 1,2-naphthoquinone-2-diazide-4-sulfonic acid ester or sulfonic acid amide. These are, for example, 1,2-benzoquinone-
2-azido-4-sulfonyl chloride, 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride, 1,
It can be obtained by subjecting an o-quinonediazidosulfonyl chloride such as 2-naphthoquinone-2-diazide-4-sulfonyl chloride to a condensation reaction with a polyhydroxy compound or a polyamine compound in the presence of a dehydrochlorination catalyst.

Examples of the polyhydroxy compound include hydroquinone, resorcinol, pyrogallol, bisphenol A, bis (4-hydroxyphenyl) methane, 2,2-
Bis (4-hydroxyphenyl) hexafluoropropane, 2,3,4-trihydroxybenzophenone, 2,
3,4,4'-tetrahydroxybenzophenone, 2,
2 ', 4,4'-tetrahydroxybenzophenone, tris (4-hydroxyphenyl) methane, 1,1,1-
Tris (4-hydroxyphenyl) ethane, 1- [1-
(4-hydroxyphenyl) isopropyl] -4-
[1,1-bis (4-hydroxyphenyl) ethyl] benzene, methyl gallate, ethyl gallate and the like.

Examples of the polyamine compound include 1,4-phenylenediamine, 1,3-phenylenediamine,
4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfide and the like.

Examples of the polyhydroxypolyamine compound include 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane and 3,3′-dihydroxybenzidine.

The o-quinonediazide compound is preferably from 5 to 100 parts by weight, more preferably from 10 to 40 parts by weight, per 100 parts by weight of the polymer represented by the general formula (1).
It is blended in the range of parts by weight. If the amount is less than 5 parts by weight, sufficient sensitivity cannot be obtained, and if it exceeds 100 parts by weight, the heat resistance of the resin composition may be reduced.

The solvent used in the present invention is defined as follows: A is a viscosity when a polymer represented by the general formula (1) is converted into a solution having a solid content of 20 wt% in N-methyl-2-pyrrolidone (NMP). When the solvent used in the present invention is used, the viscosity of 20 wt% of the polymer represented by the same general formula (1) is 1.3 A or more and 7 A or less. More preferably, it is 1.5A or more and 5A or less. It is important that the viscosity be greater than the viscosity measured by NMP. Generally, the viscosity of a polymer is determined by the interaction between the polymer and a solvent. A solvent having a small interaction force with the polymer tends to increase the interaction force between the polymers, increase the entanglement between the polymers, and increase the viscosity. When a solvent having such a small interaction force is used, the interaction between the polymer and the solvent is weakened, and not only the above-mentioned interaction between the polymers but also the interaction between the photosensitizer and the polymer is strengthened and the sensitivity is improved. In addition, in the step of applying a heat on a hot plate or the like to remove the solvent after applying the polymer solution to the substrate (pre-bake step), if the interaction between the solvent and the polymer is small, drying is quick. For this reason, where the heat-resistant resin film is obtained by development after the pre-bake step and subsequent heat treatment, since the solvent has almost completely evaporated, the shrinkage in this step is small. By reducing this shrinkage, distortion of the pattern occurring during this time can be suppressed as much as possible.

Examples of such a solvent include ethyl lactate, propylene glycol, cyclopentanone, methoxymethylbutanol, and methyl propionate. Other solvents may also dissolve the polymer represented by the general formula (1). , Can be used as long as the viscosity is 1.3 to 7 times the viscosity of the NMP solution. Also, when the solvent is used alone, the solubility of the polymer decreases,
If problems such as layer separation occur, gamma-butyrolactone, NMP, dimethylformamide, and dimethylacetamide can be mixed by mixing 10% to 50% of the total.
Solubility can also be improved.

Further, if necessary, a surfactant, an ether such as tetrahydrofuran or dioxane may be mixed for the purpose of improving the coating property between the photosensitive precursor composition and the substrate. In addition, inorganic particles such as silicon dioxide and titanium oxide, or powder of polyimide can also be added.

In order to further enhance the adhesiveness to an underlying substrate such as a silicon wafer, a silane coupling agent, a titanium chelating agent, etc. are added to the varnish of the photosensitive resin composition in an amount of 0.5%.
To 10 parts by weight, or the base substrate can be pre-treated with such a chemical solution.

When added to the varnish, a silane coupling agent such as methylmethacryloxydimethoxysilane and 3-aminopropyltrimethoxysilane, a titanium chelating agent and an aluminum chelating agent are added in an amount of 0.5 to 10% by weight based on the polymer in the varnish. Parts.

When treating the substrate, the above-mentioned coupling agent is added to a solvent such as isopropanol, ethanol, methanol, water, tetrahydrofuran, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, ethyl lactate, diethyl adipate, etc. The solution in which 5 to 20 parts by weight are dissolved is subjected to surface treatment by spin coating, dipping, spray coating, steam treatment or the like. In some cases, then 50 ° C to 300 ° C
The reaction between the substrate and the coupling agent proceeds by applying a temperature up to

Next, a method for forming a heat resistant resin pattern using the heat resistant photosensitive resin composition of the present invention will be described.

The heat-resistant photosensitive resin composition of the present invention is applied on a substrate. As the substrate, a silicon wafer, ceramics, gallium arsenide, or the like is used, but is not limited thereto. Examples of the coating method include spin coating using a spinner, spray coating, and roll coating. The coating thickness is different depending on the coating method, the solid concentration of the composition, the viscosity, and the like.
It is applied so as to have a thickness of 0.1 to 150 μm.

Next, the substrate coated with the heat-resistant photosensitive resin composition is dried to obtain a heat-resistant photosensitive resin composition film. For drying, use oven, hot plate, infrared ray, etc.
It is preferable to carry out the reaction in the range of 50 ° C to 150 ° C for 1 minute to several hours.

Next, the film is exposed to actinic radiation through a mask having a desired pattern to expose the film. Actinic rays used for exposure include ultraviolet rays, visible rays, electron beams, and X rays.
In the present invention, the i-line (365n
m), h-line (405 nm) and g-line (436 nm) are preferably used.

The pattern of the heat-resistant resin is formed by removing the exposed portion in the case of the positive type and removing the unexposed portion in the case of the negative type using a developing solution after exposure. Is done. As a developer, an aqueous solution of tetramethylammonium, diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, diethylamine, methylamine, dimethylamine,
An aqueous solution of an alkaline compound such as dimethylaminoethyl acetate, dimethylaminoethanol, dimethylaminoethyl methacrylate, cyclohexylamine, ethylenediamine, hexamethylenediamine, or N
Polar solvents such as -methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, γ-butyrolactone, and dimethylacrylamide; alcohols such as methanol, ethanol, and isopropanol; ethyl lactate and propylene glycol Esters such as monomethyl ether acetate and ketones such as cyclopentanone, cyclohexanone, isobutyl ketone and methyl isobutyl ketone may be added alone or in combination of several kinds. The alkali developer and the organic solvent-based developer described above can be used for both the positive type and the negative type, but it is preferable to use the alkali developer for the positive type. After the development, the substrate is rinsed with water, isopropyl alcohol, ethanol, butanol, propylene glycol monomethyl ether acetate or the like.

After development, the film is converted into a heat-resistant resin film by applying a temperature of 200 ° C. to 500 ° C. This heat treatment is carried out for 5 minutes to 5 hours while selecting the temperature and increasing the temperature stepwise, or while selecting a certain temperature range and continuously increasing the temperature. As an example, heat treatment is performed at 130 ° C., 200 ° C., and 350 ° C. for 30 minutes each. Alternatively, a method of linearly raising the temperature from room temperature to 400 ° C. over 2 hours may be used.

The heat-resistant resin film formed by the heat-resistant photosensitive resin composition according to the present invention is used for applications such as a passivation film of a semiconductor, a protective film of a semiconductor element, and an interlayer insulating film of a multilayer wiring for high-density mounting.

[0050]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. Measurement method of characteristics Measurement of film thickness Lambda Ace STM-602 manufactured by Dainippon Screen Mfg. Co., Ltd.
The measurement was performed with a refractive index of 1.64 for the prebaked film and a refractive index of 1.75 for the cured film. Measurement points were measured at 10 points in the diameter direction on the wafer, and an average value was obtained.

Measurement of viscosity 2.0 g of polymer powder is weighed out. The solvent used here is added so that the total weight becomes 10 g. This was stirred using a microspatula, and then placed in a shaker and shaken at 100 rpm for 2 hours to promote dissolution. After allowing this solution to stand for 48 hours, 1 ml of the solution was weighed using an E-type viscometer ELH-D manufactured by Tokimec, and the viscosity was measured at 25 ° C. At this time, a comparison was made with the viscosity when NMP was used as the solvent.

Shrinkage by curing A prebaked film formed on a silicon wafer under predetermined conditions is coated with an inert oven CLH-2 manufactured by Koyo Lindberg.
Using 1CD, under a nitrogen atmosphere (oxygen concentration: 10 ppm or less), the temperature was raised at 200 ° C. for 30 minutes, then to 350 ° C. over 1 hour, heat-treated at 350 ° C. for 1 hour, and then cooled. When the temperature became 200 ° C. or lower, it was taken out. The film thickness (Ta) before the heat treatment (curing) and the film thickness (Tb) after the curing were measured, and Tb / Ta × 100
(%) Was used to determine the shrinkage due to curing. When this number is 70% or more, distortion of the pattern due to shrinkage during curing is reduced, and stress due to shrinkage is reduced, which is preferable.

Synthesis Example 1 Synthesis of hydroxyl group-containing diamine compound 2,2-bis (3-amino-4-hydroxyphenyl)
Hexafluoropropane (BAHF) 18.3 g (0.
(0.5 mol) was dissolved in 100 ml of acetone and 17.4 g (0.3 mol) of propylene oxide, and cooled to -15 ° C. Here, 3-nitrobenzoyl chloride 20.
A solution of 4 g (0.11 mol) dissolved in 100 ml of acetone was added dropwise. After the completion of the dropwise addition, the reaction was carried out at −15 ° C. for 4 hours, and then returned to room temperature. The solution was concentrated by a rotary evaporator, and the obtained solid was recrystallized from a solution of tetrahydrofuran and ethanol.

The solid collected by recrystallization was mixed with 100 parts of ethanol.
dissolved in 300 ml of tetrahydrofuran and 5 ml of
2 g of palladium-carbon was added and stirred vigorously.
Here, hydrogen was introduced by a balloon, and the reduction reaction was performed at room temperature. After about 2 hours, it was confirmed that the balloon did not deflate any more, and the reaction was terminated. After completion of the reaction, the mixture was filtered to remove the palladium compound as a catalyst, and concentrated by a rotary evaporator to obtain a diamine compound. This is shown below.
The obtained solid was used for the reaction as it was.

[0055]

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Synthesis Example 2 Synthesis of hydroxyl group-containing acid anhydride BAHF 18.3 g (0.05 mol) under a stream of dry nitrogen.
l) and 34.2 g (0.3 m) of allyl glycidyl ether
ol) was dissolved in 100 g of gamma-butyrolactone (GBL) and cooled to -15 ° C. Here, 22.1 g of trimellitic anhydride chloride dissolved in 50 g of GBL (0.
11 mol) was added dropwise so that the temperature of the reaction solution did not exceed 0 ° C. After the completion of the dropwise addition, the reaction was carried out at 0 ° C. for 4 hours.

This solution was concentrated by a rotary evaporator and added to 1 liter of toluene to obtain an acid anhydride. This is shown below. The resulting material did not show a clear melting point up to 350 ° C.

[0058]

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Synthesis Example 3 Synthesis of naphthoquinonediazide compound 4,4 '-[1- [4- [1- (4-
Hydroxyphenyl) -1-methylethyl] phenyl]
Ethylidene] bisphenol (Honshu Chemical Industry Tris
-PA) 21.2 g (0.05 mol) and 5-naphthoquinonediazidosulfonyl chloride 37.6 g (0.1
4 mol) in 400 g of 1,4-dioxane,
Heated to 40 ° C. Here, 40 g of 1,4-dioxane
14.2 g of triethylamine (0.14 m
ol) was added dropwise so that the temperature inside the system did not become 45 ° C. or higher. After the addition, the mixture was stirred at 40 ° C. for 2 hours. The by-product triethylamine hydrochloride was filtered, and the filtrate was poured into 3 liters of 1% hydrochloric acid. Thereafter, the deposited precipitate was collected by filtration. Water 10
This precipitate was repeatedly washed twice with 1 and dried in a vacuum dryer at 50 ° C. for 20 hours to obtain a naphthoquinonediazide compound. The structure of the obtained compound is shown below.

[0060]

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6.7% of Q is hydrogen. The rest are 5-naphthoquinonediazidosulfonyl groups.

Examples 1-4, Comparative Examples 1-2 30.2 g of the hydroxyl group-containing diamine compound synthesized in Synthesis Example 1 in a 1 l four-necked flask under a stream of dry nitrogen.
(50 mmol) in N-methyl-2-pyrrolidone (NM
P) dissolved in 150 g, and 13.2 g of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (45 mm
l) was added and the mixture was stirred at 50 ° C for 3 hours. N, N-
9.5 g of dimethylformamide diethyl acetal (8
0 mmol) and stirred at 50 ° C. for 2 hours to obtain a partially esterified polymer solution. This polymer solution is
of water to give a polymer precipitate. The polymer precipitate was collected by filtration, washed again with 2 l of water, and then collected by filtration. The polymer was dried in a vacuum dryer at 80 ° C. for 48 hours.

For the measurement of the viscosity, the obtained polymer was adjusted so that the solid content concentration became 20% by weight in the predetermined solvent shown in Examples 1 to 4 and Comparative Examples 1 and 2 in Table 1. Was measured. Table 1 shows the measurement results. The polymer obtained in the same manner was adjusted to a solid content concentration of 20% by weight in NMP, and the viscosity was measured.

Also, 5 g of the obtained polymer, 1 g of the photosensitizer synthesized in Synthesis Example 3, and 0.5 g of methylene bisphenol were dissolved in 15 g of a predetermined solvent shown in Examples 1 to 4 and Comparative Examples 1 and 2 in Table 1. Was.

The above solution was applied on a 6-inch silicon wafer so that the film thickness after prebaking was 7 μm, and then a hot plate (SKW-6 manufactured by Dainippon Screen Co., Ltd.) was used.
36), and prebaked at 110 ° C. for 3 minutes to obtain a photosensitive resin precursor film. Next, an exposure machine (Nikon i-line stepper NSR-1755-i7A)
And the reticle with the pattern cut is set to 50 mJ / cm ² from 100 mJ / cm ² to 800 mJ / cm ^2.
I-ray exposure was performed at intervals of / cm ² . After that, NMD-
3 (tetramethylammonium hydroxide 2.38%
(Aqueous solution: manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 60 seconds, and then washed with water for 20 seconds to form a pattern.

Table 1 shows the results. The ratio of the film thickness (T1) before development to the film thickness (T2) of the unexposed part after development (remaining film ratio T2 / T1 × 100 (%)), and the lowest light irradiation amount that completely dissolves during the development time Are summarized in Table 1. This product was manufactured by Koyo Lindberg Inert Oven INH-21.
Heat treatment was performed at 200 ° C. for 30 minutes and at 350 ° C. for 60 minutes using a CD to convert into polyimide. Table 1 also shows the retention of the film thickness during the heat treatment (T2 / T3 × 100 (%), where T2 is the film thickness after development and T3 is the film thickness after heat treatment).

Examples 5-6, Comparative Examples 3-4 4,4'-Diaminodiphenyl ether (0.09 mol), 1,3-bis- (3-aminopropyl) tetramethyldisiloxane (0.005 mol) To N-methyl-2
-Dissolved in g of pyrrolidone at 30 ° C. Here Synthesis Example 2
61.4 g (0.1 mol) of the acid anhydride synthesized in the above was added and reacted at 30 ° C. for 1 hour and then at 50 ° C. for 3 hours. Thereafter, 15.0 g (0.1%) of isobutyl vinyl ether washed with water and dried over sodium sulfate.
(5 mol) was added and stirring was continued at 50 ° C. for 4 hours.

The polymer solution thus obtained was poured into 3 l of water to precipitate the polymer. The precipitate was collected by filtration, washed again with 3 l of water, collected by filtration, and dried in a hot air oven at 80 ° C. for 48 hours.

For the measurement of viscosity, the obtained polymer was adjusted so as to have a solid content of 20% by weight in a predetermined solvent shown in Examples 5 to 6 and Comparative Examples 3 and 4 in Table 1. Was measured. Table 1 shows the measurement results. The obtained polymer was adjusted to a solid concentration of 20% by weight in NMP, and the viscosity was measured.

Further, 5 g of the obtained polymer and a compound in which an average of three of the four phenolic hydroxyl groups of 2,3,4,4'-tetrahydroxybenzophenone were naphthoquinonediazidosulfonic acid ester (4NT-
300, manufactured by Toyo Gosei) 1 g, bisphenol Z 0.5 g
Was dissolved in 15 g of a predetermined solvent shown in Examples 5 to 6 and Comparative Examples 3 and 4 in Table 1.

For pattern formation by exposure and development, an exposure machine (Nikon g-line stepper NSR-170) was used.
5-g6E) and g-ray exposure was performed in the same manner as in Examples 1 to 4. After pattern formation, residual film ratio,
The minimum light irradiation amount and the film thickness retention were evaluated in the same manner as in Examples 1 to 4, and these values are shown in Table 1.

Examples 7 to 9 and Comparative Examples 5 to 7 Under a dry nitrogen stream, 36.6 g (0.1 mol) of bis (3-amino-4-hydroxyphenyl) hexafluoropropane was placed in a 500 ml four-necked flask. Was dissolved in 200 ml of dimethylacetamide and cooled to -15 ° C. To this was added 7.9 g (0.12 mol) of pyridine. Here, 26.6 g of 4,4'-diphenyletherdicarboxylic acid chloride dissolved in 50 ml of cyclohexanone was used.
(0.09 mol) was added dropwise so that the temperature of the solution did not exceed 0 ° C.

After completion of the dropwise addition, the mixture was stirred at -15 ° C. for 2 hours, and then the temperature was raised to 15 ° C., and the mixture was stirred for 1 hour.
Thereafter, the temperature was raised to 30 ° C. and the mixture was stirred for 2 hours.

Thereafter, 3.28 g (0.02 mol) of 5-norbornene-2,3-dicarboxylic anhydride was added, and
The mixture was stirred at 15 ° C for 1 hour and then at 25 ° C for 2 hours. Thereafter, 100 ml of dimethylacetamide was added to the solution, and the generated salt was removed by filtration. The filtrate was poured into 10 l of water, stirred for 30 minutes, and left as it was for 10 hours. The polymer precipitate formed therein was collected by filtration. The polymer was dried in a vacuum dryer at 80 ° C. for 48 hours.

For the measurement of the viscosity, the obtained polymer was adjusted so that the solid content concentration became 20% in the predetermined solvents shown in Examples 7 to 9 and Comparative Examples 5 to 7 in Table 1, and the viscosity was adjusted. It was measured. Table 1 shows the measurement results. The obtained polymer was adjusted to a solid concentration of 20% by weight in NMP, and the viscosity was measured.

5 g of the obtained polymer, 1 g of the photosensitizer synthesized in Synthesis Example 3, and 0.5 g of methylenebisphenol were prepared as shown in Table 1.
The predetermined solvent 15 shown in Examples 7 to 9 and Comparative Examples 5 to 7
g.

The pattern formation by exposure and development was performed in the same manner as in Examples 1 to 4. Further, after the pattern formation, the remaining film rate, the minimum light irradiation amount, and the film thickness retention rate were as in Examples 1 to 3.
Evaluation was performed in the same manner as in Example 4, and these values are shown in Table 1.

Examples 10 to 11 and Comparative Examples 8 to 9 31.0 g (0.1 mol) of 3,3 ', 4,4'-diphenylethertetracarboxylic dianhydride was dissolved in 100 g of gamma-butyrolactone and 15 g of pyridine. Was. Here, 27.6 g of 2-hydroxyethyl methacrylate
(0.2 mol) and stirred at 30 ° C. for 12 hours.

This solution was cooled to -10 ° C., and 40.6 g (0.2 mol) of dicyclohexylcarbodiimide dissolved in 50 g of gamma-butyrolactone heated to 40 ° C.
The solution was added so that the internal temperature did not exceed 0 ° C. After 10 minutes, bis (4-aminophenoxy-4-phenyl) sulfone 4
3.2 g (0.1 mol) of gamma-butyrolactone 100
The solution was added dropwise so that the internal temperature did not exceed 0 ° C. After dropping, 2 hours at -10 ° C, then 30 ° C
For 4 hours.

This solution was filtered to remove the generated precipitate, and the filtrate was poured into 3 l of water to precipitate a polymer. The precipitate was collected by filtration, washed with 3 l of water, collected by filtration, and dried in a hot air oven at 80 ° C. for 48 hours.

For the measurement of the viscosity, the obtained polymer was adjusted so that the solid content became 20% in the predetermined solvents shown in Examples 10 to 11 and Comparative Examples 8 to 9 in Table 1, and the viscosity was adjusted. It was measured. Table 1 shows the measurement results. The obtained polymer was adjusted to a solid concentration of 20% by weight in NMP, and the viscosity was measured.

The obtained polymer 5 g, ethylene glycol dimethacrylate 0.5 g, trimethylolpropane trimethacrylate 0.1 g, N-phenyldiethanolamine 0.1 g, Michler's ketone 0.05 g, mercaptobenzothiazole 0.05 g, 3-aminopropyl 0.08 g of triethoxysilane was added to Examples 10 to 1 in Table 1.
1. Dissolved in 15 g of the predetermined solvent shown in Comparative Examples 8 and 9.

Regarding pattern formation by exposure and development,
Exposure was performed in the same manner as in Examples 1 to 4, except that pre-baking was performed at 100 ° C. for 3 minutes. After exposure, using a developing device of SKW-636 with cyclopentanone as a developer, 20
Spray spray at 00 rotation for 30 seconds to dissolve the unexposed area, and then at 2,000 rotations for 5 seconds, simultaneously spray cyclopentanone and isopropyl alcohol,
After spraying isopropyl alcohol at 2000 rotations for 0 second, the substrate was shaken off at 3000 rotations for 15 seconds and dried.

After pattern formation, the remaining film ratio, the minimum light irradiation amount,
The film thickness retention was evaluated in the same manner as in Examples 1 to 4, and these values are shown in Table 1.

Examples 12 to 13 and Comparative Examples 10 to 11 31.0 g (0.1 mol) of 3,3 ', 4,4'-diphenylethertetracarboxylic dianhydride was dissolved in 100 g of gamma-butyrolactone and 15 g of pyridine. Was. Here, 27.6 g of 2-hydroxyethyl methacrylate
(0.2 mol) and stirred at 30 ° C. for 12 hours.

This solution was cooled to -10 ° C., and 40.6 g (0.2 mol) of dicyclohexylcarbodiimide dissolved in 50 g of gamma-butyrolactone heated to 40 ° C.
The solution was added so that the internal temperature did not exceed 0 ° C. After 10 minutes, 7.61 g (0.05 mol) of 3,5-diaminobenzoic acid, 4,4′-diaminodiphenyl ether 10.0
A solution of 1 g (0.05 mol) dissolved in 70 g of gamma-butyrolactone heated to 40 ° C. was added dropwise so that the internal temperature did not exceed 0 ° C. After dropping, at -10 ° C for 2 hours,
Thereafter, the mixture was stirred at 30 ° C. for 4 hours.

This solution was filtered to remove the generated precipitate, and the filtrate was poured into 3 l of water to precipitate a polymer. The precipitate was collected by filtration, washed with 3 l of water, collected by filtration, and dried in a hot air oven at 80 ° C. for 48 hours.

For the measurement of viscosity, the obtained polymer was adjusted to a solid concentration of 20% in a predetermined solvent shown in Examples 12 to 13 and Comparative Examples 10 to 11 in Table 1, and the viscosity was adjusted. It was measured. Table 1 shows the measurement results. The obtained polymer was adjusted to a solid concentration of 20% by weight in NMP, and the viscosity was measured.

5 g of the obtained polymer, 2-hydroxy-
1-Allyloxy-3-methacryloxypropane (70
1A Shin-Nakamura Chemical) 0.5 g, trimethylolpropane trimethacrylate 0.1 g, N-phenyldiethanolamine 0.1 g, Irgacure 784 (Ciba Specialty Chemical) 0.1 g, vinyltriethoxysilane 0.05 g, 3- 0.05 g of aminopropyltriethoxysilane was used in Examples 12 and 13 of Table 1 and Comparative Example 1
It was dissolved in 15 g of a predetermined solvent shown in 0 to 11.

Regarding pattern formation by exposure and development,
Exposure was performed in the same manner as in Examples 1 to 4. After exposure, 60% aqueous solution of 1.19% tetramethylammonium hydroxide
The pattern was formed by immersing for 20 seconds and washing with water for another 20 seconds.

After the pattern formation, the remaining film ratio, the minimum light irradiation amount,
The film thickness retention was evaluated in the same manner as in Examples 1 to 4, and these values are shown in Table 1.

[0092]

[Table 1]

The abbreviations used in Table 1 are as follows. ACO: acetone CHO: cyclohexanone DAA: diacetone alcohol EL: ethyl lactate DMI: dimethyl imidazoline GBL: gamma butyrolactone MMB: 3-methoxy-3-methylbutanol NMP: N-methyl-2-pyrrolidone PGM: propylene glycol monomethyl ether

[0094]

According to the present invention, a high-sensitivity photosensitive resin composition can be obtained in which pattern processing can be carried out with a low light exposure and the shrinkage of the film after pattern formation is small.

Continued on the front page F-term (reference) 2H025 AA01 AA10 AA20 AB16 AC01 AD01 AD03 BC13 BC69 BC70 BC86 BE01 BJ06 CB25 CB26 CB45 CC03 FA17 4J002 CM031 CM041 EC047 EE036 EE037 EE056 EH037 EN076 EQ016 ER006 ES006 EU 316 EU 316

Claims (2)

[Claims] 1. A heat-resistant photosensitive resin composition comprising (a) a polymer having a structural unit represented by the general formula (1), (b) a photosensitizer, and (c) a solvent, When the viscosity of the solution when the concentration of the polymer represented by the general formula (1) is 20% by weight is equal to the concentration of the polymer represented by the general formula (1) using only the solvent N-methyl-2-pyrrolidone The heat-resistant photosensitive resin composition is 1.3 to 7 times the viscosity of the solution of (1). Embedded image (R ¹ is a divalent to octavalent organic group having at least 2 or more carbon atoms, R ² is a divalent to octavalent organic group having at least 2 or more carbon atoms, R ³ , R ⁴ , R ⁵ , R ⁶
Represents hydrogen or a monovalent alkyl group having 1 to 20 carbon atoms, and a monovalent organic group having 1 to 3 unsaturated bonds. Further, R ⁵ and R ⁶ are not all hydrogen. n is an integer from 3 to 100,000, and p and q are integers from 0 to 4. r and s represent an integer from 0 to 2. ) 2. The heat-resistant photosensitive resin composition according to claim 1, wherein the solvent is a mixed solvent of two or more kinds.