JPS6313032A - Organic solvent soluble positive type photosensitive polyimide composition - Google Patents

Abstract

PURPOSE:To obtain an org. solvent soluble positive type photosensitive polyimide compsn. which has high sensitivity and excellent heat resistance and dimensional stability and is industrially easily produceable by forming the photosensitive compsn. from a prescribed arom. polyimide and orthoquinone diazide compd. CONSTITUTION:The photosensitive polyimide compsn. is constituted of the org. solvent soluble arom. polyimide consisting of the condensation product of a biphenyl tetracarboxylic acid component and org. diamine component and the orthoquinone diazide compd. 2,3,3',4'-Biphenyl tetracarboxylic acid or the dianhydride thereof is more particularly preferable as the phenyl tetracarboxylic acid component in terms of solubility. The org. diamine compd. in which two amino groups are bonded to an arom. ring or arom. heterocycle directly or via one methylene group is more preferable as the org. diamine component in terms of heat resistance. The amt. of the diazide compd. to be compounded is 0.2-30pts.wt., more particularly preferably 1-20pts.wt. per 100pts.wt. polyimide.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has high sensitivity, excellent heat resistance and dimensional stability, excellent storage stability, and is industrially easy to manufacture. It also relates to a positive-working photosensitive polyimide composition that is soluble in solvents and has excellent mechanical properties.
The positive photosensitive polyimide composition of the present invention is particularly suitable for use as a puffed basis film for electronic components such as semiconductors and resistors, as an insulating film between the eyebrows of multilayer integrated circuits, as a protective film for soldering of printed circuits, and as a protective film for soldering of printed circuits.
It can be suitably used as a forming material for alignment films for liquid crystals, α-ray shielding films for memory devices, wA edge films for electrolytic capacitors, etching resists, etc., and can be applied to other known uses of polyimide.

[Conventional technology and its problems]

Aromatic polyimide is an organic material suitable for application to electronic components due to its heat resistance, electrical properties, mechanical properties, etc.

Furthermore, if aromatic polyimide is imparted with photosensitivity, the working process will be streamlined, and therefore various studies have been made on imparting photosensitivity.

As a method for imparting photosensitivity to aromatic polyimide, since aromatic polyimide is generally poorly soluble in organic solvents, a method using a soluble precursor for imparting photosensitivity is known.

For example, JP-A-54-116216 and JP-A-5
4-116217, a method of chemically bonding a crosslinkable group to a soluble precursor, and JP-A No. 54-1
There are methods of mixing crosslinkable monomers as described in JP-A-45794 and JP-A-57-168942.

However, in any of the above methods, it is necessary to perform imide ring closure by heat treatment after photoprocessing, and at that time, loss of film thickness and volume shrinkage due to dehydration accompanying imide ring closure and volatilization of crosslinkable group components. A reduction in dimensional accuracy is an unavoidable drawback.

Furthermore, the heat treatment process may also lead to deterioration of other electronic components or organic materials.

In order to prevent the deterioration of dimensional accuracy due to the volume shrinkage caused by the above-mentioned imide ring closure, a photosensitive polyimide in which a crosslinkable group is chemically bonded to a soluble polyimide was disclosed in JP-A-58-29821.
This method has been proposed in Japanese Patent Application Laid-open No. 61-59334.

However, these photosensitive polyimides also inevitably suffer from deterioration in dimensional accuracy due to volume shrinkage due to continuous loss of crosslinkable groups at high temperatures, and also require complicated steps to introduce crosslinkable groups. Furthermore, the polyimide of the former (Japanese Unexamined Patent Publication No. 58-29821) has poor photocurability.

In addition, a photosensitive polyimide in which a relatively low-molecular-weight crosslinkable alkyl group is directly bonded to polyimide was published in JP-A-58-191.
This method has been proposed in Publication No. T and Japanese Unexamined Patent Publication No. 60-155277.

However, although these photosensitive polyimides have little deterioration in dimensional accuracy due to volumetric shrinkage, they have the disadvantage of poor photocurability.

Therefore, an object of the present invention is to provide an organic solvent-soluble positive photosensitive polyimide composition that has high sensitivity, excellent heat resistance and dimensional stability, and is easy to manufacture industrially.

[Means for solving problems]

As a result of various studies, the present inventors have found that a composition in which an orthoquinone diazide compound is added to an organic solvent-soluble polyimide consisting of a polycondensate of a biphenyltetracarboxylic acid component and an organic diamine component is a polyimide having a crosslinkable group. It has been found that the film has high positive photosensitivity even though it does not contain crosslinking additives, and can achieve the above object.

The present invention was made based on the above findings, and consists of an organic solvent-soluble aromatic polyimide made of a polycondensate of a biphenyltetracarboxylic acid component and an organic diamine component, and an organic solvent-soluble positive polyimide made of an orthoquinone diazide compound. The present invention provides a type photosensitive polyimide composition.

The organic solvent-soluble positive-working photosensitive polyimide composition of the present invention will be described in detail below.

The organic solvent-soluble polyimide constituting the positive photosensitive polyimide composition of the present invention can be obtained by polymerizing and imidizing a biphenyltetracarboxylic acid component and an organic diamine component by a known method.

The biphenyltetracarboxylic acid component used in the production of the organic solvent-soluble polyimide is specifically 3.3'', 4,4°-biphenyltetracarboxylic acid or its dianhydride, 2.2'.

Examples include 3.3°-biphenyltetracarboxylic acid or its dianhydride, 2,3.3'', 4°-biphenyltetracarboxylic acid or its dianhydride, and among these,
2,3.3'', 4°-biphenyltetracarboxylic acid or its dianhydride is particularly preferred from the viewpoint of polymer solubility.

In addition, in the organic diamine component used in the production of the organic solvent-soluble polyimide, from the viewpoint of heat resistance, two amino groups are bonded to the aromatic ring or aromatic heterocycle directly or through one methylene group. An organic diamine compound having the following formula is preferable, and examples of such an organic diamine compound include those represented by the following formula.

Among these organic diamine compounds, polycyclic aromatic diamine compounds are particularly preferred from the viewpoint of polymer solubility.

Further, the organic diamine compound described above may have a substituent such as an alkyl group, an alkoxyl group, or a hydroxyl group within a range that does not adversely affect the heat resistance of the polyimide.

As the organic diamine component, the organic diamine compounds described above may be used alone or in combination of two or more.

Furthermore, in order to improve the adhesiveness of polyimide, as the organic diamine component, within a range that does not reduce the heat resistance,
An aliphatic compound having a siloxane structure can also be used in combination with the above organic diamine compound. Preferred examples of such compounds include compounds represented by the following formulas.

CH3CH.

The organic solvent-soluble polyimide used in the present invention is 0.5 g of polyimide/1 1 N-methyl-2-pyrrolidone.
It is preferable that the logarithmic viscosity measured at 30°C as a solution having a concentration of 00+sl is in the range of 0.1 to 3.0, particularly 0.2 to 2.0.

To explain in more detail the production of the organic solvent-soluble polyimide used in the present invention, the proportions of the biphenyltetracarboxylic acid component and the diamine component used in synthesizing the polycondensate are approximately equimolar. . Then, both components can be synthesized by polymerizing and imidizing them in one step at a high temperature of 100° C. or higher. Alternatively, it can be synthesized by a two-step reaction in which a polymerization reaction is first performed and then an imidization reaction is performed at a relatively low temperature.

Further, the orthoquinonediazide compound constituting the photosensitive polyimide composition of the present invention may be any compound containing one or two or more orthoquinonediazide groups in the molecule, such as orthobenzoquinonediazide compounds,
Examples include ortho-naphthoquinone diazide compounds, ortho-quinoline quinone diazide compounds, and ortho-naphthoquinone diazide compounds are particularly preferred.

The above-mentioned orthoquinonediazide compound is usually preferably used as an orthoquinonediazide sulfonic acid ester or an orthoquinonediazide sulfonic acid amide.

These orthoquinone di7didosulfonic acid esters or orthoquinonediazide sulfonic acid amide are usually obtained by a condensation reaction between orthoquinonediazide sulfonic acid chloride and a compound having a hydroxyl group or an amino group.

Examples of the orthoquinonediazide sulfonic acid component constituting the orthoquinonediazide sulfonic acid chloride include 1,2-naphthoquinone-2-diazide-4-sulfonic acid, 1,2-naphthoquinone-2-diazide-5-sulfonic acid, etc. can be mentioned.

In addition, examples of the above-mentioned compounds having a hydroxyl group or an amino group include ethylene glycol, phenol, 0-cresol, m-cresol, p-cresol, catechol, hydroquinone, 2,4-dihydroxybenzophenone, 2,3,4-) Dihydroxybenzophenone 2.
2゛・4・4゜-tetrahydroxybenzophenone, 2.2-bis(4-hydroxyphenyl)propane,
4゜4゜-dihydroxydiphenylsulfone, ethanolamine, aniline, 2-hydroxyaniline, 3-
Hydroxyaniline, 4-hydroxyaniline, etc. can be mentioned.

The blending amount of the orthoquinone diazide compound is 0.2 to 3 parts by weight based on 100 parts by weight of the organic solvent-soluble polyimide.
The amount is preferably 0 parts by weight, especially 1 to 20 parts by weight. If the amount is less than 0.2 parts by weight, the sensitivity of the resulting composition will be low, and if it is more than 30 parts by weight, the sensitivity of the resulting composition will decrease. The properties of the film formed are deteriorated.

When the positive photosensitive polyimide composition of the present invention is used as a relief pattern forming material, it is used as a solution dissolved in an organic solvent. Examples of the organic solvent include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-
Vinyl-2-pyrrolidone, dimethyl sulfoxide, hexamethylene phosphoamide, m-cresol, etc. can be mentioned, and mixed solvents of xylene, ethyl cellosolve, diglyme, dioxane, etc. and the above organic solvents can also be used. The preferred polymer concentration of the organic solvent solution of the positive photosensitive polyimide composition described above is 2 to 40% by weight.

The organic solvent solution of the above-mentioned positive photosensitive polyimide composition can be prepared by, for example, dropping a reaction solution obtained by polymerizing and imidizing the acid component and the diamine component into a poor solvent. After the polyimide is precipitated and dried, the polyimide can be prepared by dissolving the polyimide at the above polymer concentration in an organic solvent together with the orthoquinone diazide compound. Furthermore, when the polymerization/imidization reaction is carried out in one step at a temperature of 150° C. or higher, it can also be prepared by adding the orthoquinonediazide compound to the reaction solution after cooling the reaction solution.

An adhesion aid may be appropriately added to the organic solvent solution of the positive photosensitive polyimide composition described above in order to improve the adhesion to the support. Such adhesion aids include, for example, γ-methacryloxypropyltrimethoxysilane, T-aminopropyltriethoxysilane, γ-
Glycidoxypropyltrimethoxysilane, r-(2-
Examples include aminoethyl)aminopropylmethyldimethoxysilane.

According to the positive photosensitive polyimide composition of the present invention, a positive relief pattern can be formed in the following manner by preparing a solution of the positive photosensitive polyimide composition in a solvent as described above.

That is, first, an organic solvent solution of the positive photosensitive polyimide composition described above is applied to a substrate, and this is dried to remove the Il-containing solvent. Coating onto the substrate can be performed using, for example, a rotary coater. The coating film should be dried at a temperature of 150°C or lower, preferably 100°C or lower. At this time, reduced pressure may or may not be applied. After drying, a positive photomask is placed on the coating film and exposed to ultraviolet rays, visible light, Irradiate with actinic rays such as electron beams and X-rays.

Next, a positive relief pattern of polyimide is obtained by washing away the exposed area with a developer.

As the above developer, primary organic amine compounds such as propylamine, butylamine, and monoethanolamine, primary organic diamine compounds such as ethylenediamine and trimethylenediamine, hydrazine, etc. are used alone or in combination of two or more. It is preferable. In addition, these amine compounds include methanol, ethanol, 2-propanol,
Polyimide nonsolvents such as ethylene glycol, ethyl cellosolve, butyl cellosolve, diethylene glycol, ethyl carpitol, butyl carpitol, water, and N-
It is also possible to use a mixture of polyimide solvents such as methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, and hexamethylenephosphoamide.

The above-mentioned development is preferably performed at a developer temperature in the range of 0 to 150°C.

The polyimide positive relief pattern obtained as described above can be used as it is for the various purposes mentioned above, but in order to remove trace amounts of solvent remaining in the coating film,
The above-mentioned positive relief pattern, which is preferably heat-treated at a temperature of about °C, is formed from the positive photosensitive polyimide composition of the present invention that does not contain a polyimide having a crosslinkable group or a crosslinkable additive. It is not accustomed to volume shrinkage due to volatilization of crosslinking groups at high temperatures, and depending on the application, heat treatment can be performed up to about 400°C.

【Example〕

Below, production examples showing the production of organic solvent-soluble polyimide constituting the composition of the present invention and examples of the present invention are listed.

Production Example 1 Under a nitrogen stream, 6.721 g of 2,3.3′,4°-biphenyltetracarboxylic dianhydride and bis(4-(
4'-Aminophenoxy)phenyl]sulfone 10.0
62 g of N-methyl-2-pyrrolidone (NMP) 80
+*l and stirred at a reaction temperature of 180° C. for 5 hours to perform a polymerization/imidization reaction. This reaction solution was dropped into methanol to precipitate polyimide, which was filtered to obtain polyimide powder. Logarithmic viscosity of this polyimide powder (
Concentration: Polyimide powder 0.5 g/NMP 100+*
l, measurement temperature: 30°C) was 0.77.

Production Examples 2 and 3 Polyimides having the logarithmic viscosities shown in Table 1 below were obtained in the same manner as Production Example 1 except that the polyimide synthesis conditions in Production Example 1 were changed to the conditions shown in Table 1 below.

Example 1 A silane coupler (KBM603 manufactured by Shin-Etsu Chemical ■: 6-(2-aminoethyl)aminopropyltrimethoxysilane) was coated on a glass substrate whose surface was coated with 5iO1.
3% 2-propertool solution at 2500 r, p, m, 3
Spin coating was performed for 0 seconds. This coupler solution-coated substrate was air-dried at room temperature for 3 minutes and then heat-treated at 150° C. for 10 minutes to perform coupler treatment on the substrate.

On the other hand, 1.4 g of the polyimide powder obtained in Production Example 1 and 0.14 g of the orthoquinonediazide compound shown in Table 2 below.
g was dissolved in 8.6 g of NMP and filtered through a 1 μm filter to obtain an organic solvent solution of the positive photosensitive polyimide composition of the present invention.

The obtained solution was applied to the above-described coupler-treated glass substrate using a spinner at 2500 r, p, m.

The coating was then spin-coated for 30 seconds at 70°C.
It was dried by heating for 0 minutes to obtain a coating film with a thickness of 3.0 μm. Light from a 250W high-pressure mercury lamp (Mikasa ■) was applied to this coating film through a test mask (Toppan Printing ■, Tosopan Test Chart N).
Manufacture, mask alignment.

The mold was irradiated for 7 seconds. The UV intensity on the exposed surface is 6.5mW/- in the 35On+* wavelength range.
(Measured using an ultraviolet illuminance meter UV-MOI, model @Oak Seisakusho), that is, exposed to 50 mj/-. After exposure, 5
Development with monoethanolamine warmed to 0°C followed by room temperature monoethanolamine followed by room temperature 2-
A positive relief pattern was obtained by cleaning using a propatool. Defining the resolution as the minimum mask pattern that can be identified in the positive relief pattern obtained, this pattern had a resolution of 6 μm and had a sharp end surface. Moreover, the coating film thickness after development was 2.2 μm.

Next, this pattern was heated at 150°C for 30 minutes and then at 200°C for 30 minutes to remove residual solvent in the pattern, resulting in a film thickness of 1.9 μm.Next, this pattern was heated under a nitrogen stream. After heating at 300°C for 30 minutes, and then heating at 400°C for 30 minutes, the film thickness was 1.8
It was μm. Even after heating at 400° C., this patterned film showed no deformation, blurring, etc., and had good heat resistance.

Examples 2 to 7 Positive-working photosensitive polyimide compositions of the present invention were prepared in the same manner as in Example 1 except that the composition shown in Table 2 below was used.
Solvent solutions were obtained respectively. Using these solutions, pattern formation and heat treatment were performed in the same manner as in Example 1, except that the coating rotation speeds shown in Table 3 below were used and the developer shown in Table 3 below was used. The results of this pattern formation and heat treatment are shown in Table 3 below. In all of Examples 2 to 7, a positive leap pattern with sharp end faces was obtained, and even after heat treatment up to 400°C, None of the patterned films showed any deformation, blurring, etc., and had good heat resistance.

While conventional photosensitive polyimide compositions required exposure of 100 mJ/cd or more, the positive photosensitive polyimide composition of the present invention required exposure of 50 mJ/cd, as is clear from the results shown in Table 3 below. It is highly sensitive in that a pattern can be obtained with a small amount of exposure, and it is also found that there is little change in film thickness even after going through a high temperature process, and that it has excellent dimensional stability.

〔Effect of the invention〕

The positive photosensitive polyimide composition of the present invention has high sensitivity even though it does not contain a polyimide having a crosslinkable group or a crosslinkable additive, and it also contains a polyimide having a crosslinkable group or a crosslinkable additive. Therefore, it has excellent heat resistance and dimensional stability, as well as excellent storage stability, and is easy to manufacture industrially. Furthermore, it has excellent electrical and mechanical properties, and is particularly useful for semiconductors, resistors, etc. Suitable as a forming material for passivation films for electronic components, glabellar insulating films for multilayer integrated circuits, protective films for soldering of printed circuits, alignment films for liquid crystals, alpha-ray shielding films for memory devices, insulating films for electrolytic capacitors, etching resists, etc. It can be used for.

Claims (1)

[Claims] An organic solvent soluble positive photosensitive polyimide composition comprising an organic solvent soluble aromatic polyimide comprising a polycondensate of a biphenyltetracarboxylic acid component and an organic diamine component, and an orthoquinone diazide compound.