JPH0149929B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel photosensitive polymer composition that provides a heat-resistant polymeric material. Conventionally, as a heat-resistant photosensitive material, a polymer mainly composed of polyamic acid, which is a precursor of polyimide, and a compound containing a carbon-carbon double bond and an amino group or a quaternized salt thereof, which can be dimerized or polymerized by actinic radiation, have been used. Mixed photosensitive materials are known (Japanese Unexamined Patent Publication No. 1983
−145794). However, this material had a low sensitivity of several thousand mJ/cm ² and was insufficient for practical use. An object of the present invention is to provide a highly sensitive photosensitive polymer composition that eliminates the drawbacks of the prior art described above. As a result of intensive study to achieve the above purpose, (a) general formula; (However, in the formula, R ¹ is a trivalent or tetravalent organic group
R ² represents a divalent organic group, and M represents hydrogen, an alkali metal ion or an ammonium ion. n is 1 or 2. ) A polymer whose main component is a repeating unit represented by (b) general formula,

[Formula] (However, in the formula, Ar is an aromatic cyclic group consisting of two or more benzene rings or heterocycles, and X is N ₃ -
or N ₃ SO ₂ --, Y is a monovalent group selected from hydrogen, an alkyl group, an alkoxy group, a nitro group, a carboxyl group, a sulfonic acid group, and a halogen;
R ³ represents a divalent organic group connecting Ar and N, and R ⁴ and R ⁵ represent hydrogen or a lower alkyl group. It was discovered that a system using a photosensitive polymer composition consisting of an amine compound represented by Ta.
In the present invention, an amine compound having an azide photosensitive group with high photosensitivity is introduced into a polyamic acid by ionic bonding with a carboxyl group of a side chain of the polyamic acid, thereby producing a highly sensitive photosensitive material.
In particular, since the aromatic ring of the aromatic azide photosensitive group is polycyclic, the ultraviolet absorption range is spread over a wide wavelength range, and the photosensitive group receives a large amount of light, resulting in high sensitivity. have According to the present invention, it has become possible to form a positive image with a short exposure time. The present invention will be explained in detail below. The above polyamic acid [ ] can be converted into polyimide by heat treatment, and these polyimides have heat resistance. The polymer represented by the repeating unit [ ] may consist only of [ ] or may be a copolymer with other repeating units. Examples of these include polyesteramide acid, polyhydrazideamide acid, and the like. The type and amount of repeating units used in the copolymerization are desirably selected within a range that does not significantly impair the heat resistance of the polyimide obtained by the final heat treatment. As for the heat resistance of the polyimide, it is desirable that the formed relief pattern is maintained even when heated at 300 to 400 DEG C. for 1 hour in a nitrogen atmosphere. [] In the formula, R ¹ and R ² are preferably an aromatic ring-containing organic group or a heterocyclic ring-containing organic group from the viewpoint of heat resistance when used as a polyimide. However, it is not limited to these as long as it imparts heat resistance to polyimide. As an example of R ¹ :

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[Formula] (In the formula, the bond represents a bond with a carbonyl group of the polymer main chain, and the carboxyl group is located at the ortho position to the bond.) Examples include, but are not limited to, the following. As an example of R ²

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Typical examples include, but are not limited to. Further, these may have substituents such as amino groups, amide groups, carboxyl groups, sulfonic acid groups, etc., as long as they do not adversely affect the heat resistance of the polyimide. Preferably, Examples include. As mentioned above, the polyamic acid represented by the repeating unit [ ] is usually obtained by reacting a diamine compound with an acid dianhydride in an approximately equimolar amount. An aprotic polar solvent is preferably used from the viewpoint of solubility of the polyamic acid.
N-methyl-2-prolidone, N,N-dimethylformamide, N,Z-dimethylacetamide,
Typical examples include dimethyl sulfoxide, N-acetyl-ε-caprolactam and 1,3-dimethyl-2-imidazolidinone. general formula,

[Formula] (However, in the formula, Ar is an aromatic cyclic group consisting of two or more benzene rings or heterocycles, and X is N ₃ - or
N ₃ SO ₂ --, Y is a monovalent group selected from hydrogen, an alkyl group, an alkoxyl group, a nitro group, a carboxy group, a sulfonic acid group, and a halogen; R ³ is a divalent organic group connecting Ar and N; R ⁴ and R ⁵ represent hydrogen or a lower alkyl group. ) as an example of Ar in the amine compound represented by

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Examples include [Formula]. Examples of ^R3 include alkylene,

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[Formula]-O-R ⁶ ,

[Formula] - SO ₂ -R ⁶ -, -S-R ⁶ -, -SO ₃ -R ⁶ - (R ⁶ represents alkylene or a divalent hydrocarbon group having a carbon-carbon unsaturated bond), etc. Can be mentioned.
R ⁴ R ⁵ is hydrogen or a lower alkyl group. The compound [] may have an amino group and an aromatic azide group in the molecule, and is not limited to the above examples. Preferably,

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【formula】 Examples include. The compound [] is preferably blended in a proportion of 0.01 equivalent or more and 5 equivalents or less with respect to the carboxyl group of the side chain of the polymer [] or its anion, but more preferably 0.1
It is desirable that the amount is blended in a proportion of at least one equivalent and no more than 2 equivalents. Deviation from this range will adversely affect developability, storage stability of the varnish, etc. A sensitizer may be appropriately added to the above composition for the purpose of improving sensitivity, but the amount of addition is [],
When the total of the compounds represented by [] is 100 parts by weight, it is preferable to use 0.1 parts by weight or more and 10 parts by weight or less. Deviation from this range may adversely affect the developability and the heat resistance of the final polyimide product. bring. Compounds effective for sensitizing aromatic azide compounds have been reported in detail by Tsunoda and Yamaoka (Phot. Sci. Eng, 17-, 390 (1973)). Examples of preferably used sensitizers include anthrone, 1,9-benzaanthrone, acridine, cyanoacridine, nitropyrene, 1,8-dinitropyrene, mihiraketone, 5-nitroacenaphthene, 2-nitrofluorene, and pyrene. 1,6-quinone, 9-fluorenone, 1,2-benzanthraquinone, anthantrone, 2-chloro-1,2-benzanthraquinone, 2-bromobenzanthraquinone, 2-chloro-1,8-phthaloylnaphthalene, etc. Can be mentioned. In order to improve the adhesion between the coating film of the light- and radiation-sensitive polymer composition according to the present invention or the polyimide film after heat curing and the supporting substrate, the supporting substrate may be appropriately treated with an adhesion promoter. The photosensitive polymer composition according to the present invention is used in the form of a solution in which the above components are dissolved in a suitable organic solvent. In this case, the solvent used is preferably an aprotic polar solvent from the viewpoint of solubility; Methyl
2-pyrrolidone, N-acetyl-2-pyrrolidone, N-benzyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphorotriamide, N-acetyl-ε-caprolactam , dimethylimidazolidinone and the like. These may be used alone or in combination. The amount of solvent is [], [], the total amount of sensitizer added as necessary.
When expressed as 100 parts by weight, 100 parts by weight or more
It is desirable to use it in an amount of 10,000 parts by weight or less, more preferably 200 parts by weight or more and 5,000 parts by weight or more, and if it deviates from this range, it will adversely affect film forming properties. Examples of the supporting substrate include metals, glass, semiconductors, metal oxide insulators (eg, _TiO2 , _Ta2Os , SiO2 _, etc.), silicon nitride, and the like. The photosensitive polymer composition according to the present invention can be patterned using conventional microfabrication techniques. The present polymer composition can be applied to the support by means such as spin coating using a spinner, dipping, spraying, and printing, which can be selected as appropriate. The thickness of the coating film can be adjusted by adjusting the coating means, the solid content concentration of the varnish of the present polymer composition, the viscosity, etc. A relief pattern is obtained by irradiating the photosensitive polymer composition according to the present invention, which has become a coating film on a display substrate, with ultraviolet rays, and then dissolving and removing the unexposed areas with a developer. The light source is not limited to ultraviolet light, but may also be visible light or radiation. As a developer, N-methyl-2-pyrrolidone,
N-acetyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphortriamide, dimethylimidazolidinone, N-
Benzyl-2-pyrrolidone, N-acetyl-ε-
Aprotic polar solvents such as caprolactam alone or methanol, ethanol, isopropyl alcohol, benzene, toluene, xylene,
It can be used as a mixture with a polyamic acid non-solvent such as methyl cellosolve. The relief pattern formed by development is then washed with a rinse solution to remove the development solvent. For the rinsing solution, a polyamic acid non-solvent having good miscibility with the developer is used, and suitable examples include methanol, ethanol, isopropyl alcohol, benzene, toluene, xylene, and methyl cellosolve. The relief pattern polymer obtained by the above treatment is a polyimide precursor, and by treating it at a heating temperature selected from the range of 150℃ to 450℃, it becomes heat-resistant with imide rings and other cyclic groups. It becomes a relief pattern of the polymer. Hereinafter, the present invention will be explained with reference to Examples. Example 1 100 g (0.5 mol) of 4,4'-diaminodiphenyl ether was dissolved in N-methyl-2-pyrrolidone under a nitrogen stream to prepare an amine solution. Next, while keeping this solution at a temperature of about 15°C in an ice bath,
While stirring, 109 g (0.5 mol) of pyromellitic dianhydride was added. After the addition is complete, heat at approximately 15°C 3.
Polyamic acid with a viscosity of 60 poise (30℃) after reacting for a period of time A solution (A) was obtained. 2-(N,N-dimethylamino) to 20g of solution (A)
2.68 g (0.01 mol) of ethyl 4'-azidonaphthyl ketone was dissolved and then filtered under pressure using a 5 μm pore filter. The obtained solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to obtain a coating film with a thickness of 0.8 μm. This coating was closely covered with a striped photomask and exposed to ultraviolet light using a 500W Xe-Hg lamp. At a wavelength of 365nm, which is the intensity of ultraviolet rays on the exposed surface.
It was 10mW/ ^cm2 . After exposure, N-methyl-2-
It was developed with a mixture of 5 volumes of pyrrolidone and 1 volume of ethanol, and then washed with a rinse solution (ethanol) to obtain a relief pattern. When the change in residual film thickness is measured over time and the exposure amount that gives a value of 0.5 when the coating film thickness is normalized by the residual film thickness is defined as the sensitivity, the sensitivity is
It was 20mJ/ ^cm2 . A relief pattern with sharp edges was obtained with an exposure dose three times the sensitivity. Even when this pattern was heated at 400°C for 60 minutes, no blurring of the pattern was observed. Example 2 2-(N,N
-dimethylamino)ethyl, 0.27 g (0.001 mol) of 4'-azidonaphthorketone was dissolved, and then 5 μm
Pressure was applied using a pore filter. The obtained solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to obtain a coating film of 1.0 μm. This coating film was closely covered with a striped photomask and irradiated with ultraviolet light using a 500W high-pressure mercury lamp.
The intensity on the exposed surface was 8 mW/cm ² (365 nm).
After exposure, it was developed with a mixture of 4 volumes of N,N-dimethylacetamide and 1 volume of ethanol, and then washed with a rinse solution (ethanol) to obtain a relief pattern. The sensitivity was 140 mJ/cm ² , and no blurring of the pattern was observed even when the resulting pattern was heated at 400°C for 60 minutes. Example 3 2-(N,N
-dimethylamino)ethyl, 5.36 g (0.02 mol) of 4'-azitonaphthyl ketone was dissolved, and then 5 μm
Pressure was applied using a pore filter. The obtained solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to form a 3.2μm
A thick coating film was obtained. This coating film was closely covered with a striped photomask and irradiated with ultraviolet light using a 500W high-pressure mercury lamp. The intensity on the exposed surface was 8 mW/cm ² (365 nm). After exposure, it was developed with a mixture of 3 volumes of dimethylformamide and 2 volumes of ethanol, and then washed with a rinse solution to obtain a relief pattern. The sensitivity is
It was 21 mJ/cm ² , and no blurring was observed even when the pattern was heated at 400°C for 60 minutes. Example 4 90 g of diaminodiphenyl ether under nitrogen flow
(0.45 mol), 11.4 g (0.05 mol) of 4,4′-diaminodiphenyl ether-3-carbonamide
-Methyl-2-pyrrolidone (1764 g) was dissolved to prepare an amine solution. Next, while keeping this solution at a temperature of about 15°C in an ice bath, 54.5 g (0.25 mol) of pyromellitic dianhydride, 3,3',4,
4′-Benzophenonetetracarboxylic dianhydride
80.5 g (0.25 mol) was added. After adding
Polyamic acid with a viscosity of 55 poise (at 30°C) is further reacted for 3 hours at approximately 15°C.

[Formula] (However, R ⁷ is

[Formula] and

[Formula] is 1:1, R ⁸ is

[Formula] and

[Formula] is 9:1. ) solution (B) was obtained. 2.84 g of 2-(N,N-dimethylamino)ethyl 4-azido-1-naphthalenecarboxylate in solution (B)
(0.01 mol) was dissolved and then filtered under pressure using a 5 μm pore filter. The obtained solution was applied onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to obtain a coating film with a thickness of 2.4 μm. This coating film was closely covered with a striped photomask and irradiated with ultraviolet light using a 500WXe-Hg lamp. The intensity of ultraviolet rays on the exposed surface was 8 mW/cm ² (365 nm). After exposure, N-methyl-2-pyrrolidone 5
A relief pattern was obtained by developing with a mixture of 1 volume of ethanol and 1 volume of ethanol, followed by washing with a rinse solution (ethanol). The sensitivity was 15mJ/ ^cm2 . Even when this pattern was heated at 400°C for 60 minutes, no blurring of the pattern was observed. Example 5 Add 5-azide to 20 g of the solution (B) obtained in Example 4.
3.16 g (0.01 mol) of 1-naphthyl 2'-(N,N-dimethylamino)ethylsulfone was dissolved and then filtered under pressure using a 5 μm filter. The obtained solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70° C. for 30 minutes to obtain a coating film with a thickness of 2.7 μm. This coating was closely covered with a striped photomask and exposed to ultraviolet light using a 500W high-pressure mercury lamp. The UV intensity on the exposed surface is 9mW/cm ²
(365nm). After exposure, N-methyl-2-
It was developed with a mixture of 5 volumes of pyrrolidone and 1 volume of ethanol, and then washed with a rinse solution (ethanol) to obtain a sharp relief pattern on the edge surface.
The sensitivity is 25mJ/ ^cm2 , and this pattern is heated at 400℃.
No blurring of the pattern was observed even after heating for 60 minutes. Example 6 Add 9-azide to 20 g of the solution (B) obtained in Example 4.
Dissolve 3.34 g (0.01 mol) of 2-(N,N-dimethylamino)ethyl 10-naphthalenecarboxylate,
Then, the mixture was subjected to pressure filtration using a filter with 5 μm pores. The obtained solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to obtain a coating film with a thickness of 2.2 μm. This coating was closely covered with a striped photomask and exposed to ultraviolet light using a 500W high-pressure mercury lamp. The UV intensity on the exposed surface is 9mW/cm ²
(365nm). After exposure, N-methyl-2-
It was developed with a mixture of 5 volumes of pyrrolidone and 1 volume of ethanol, and then washed with a rinse solution (ethanol) to obtain a sharp relief pattern on the edge surface.
The sensitivity is 18mJ/ ^cm2 , and this pattern is
No blurring of the pattern was observed even after heating for 60 minutes. Comparative Example Experimental results obtained using a method of adding carbon-carbon double bonds and amino groups or quaternized salts thereof that can be doubled or polymerized by actinic radiation to a polymer mainly composed of polyamic acid (Japanese Patent Application Laid-open No. 145794-1982) It is shown below as a comparative example. 2-(N,N
-Dimethylamino)ethyl methacrylate 1.57g
(0.01 mol) was dissolved and filtered under pressure using a 5 μm pore filter. The obtained solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70° C. for 30 minutes to obtain a coating film with a thickness of 3.2 μm. This coating was closely covered with a striped photomask and exposed to ultraviolet light using a 500W high-pressure mercury lamp. After exposure, N,N-dimethylacetamide 5
and 1 volume of ethanol, followed by washing with ethanol to obtain a relief pattern. The sensitivity was 3200 mJ/cm ² , which was lower than any of Examples 1 to 6. The light- and radiation-sensitive polymer composition according to the present invention significantly improves photosensitivity, which has been a problem in the past. Applications to which the material according to the present invention can be applied include insulating films for semiconductors, heat-resistant resists, and the like.

Claims (1)

[Claims] 1 (a) General formula, (However, in the formula, R ¹ is a trivalent or tetravalent organic group
R ² represents a divalent organic group, and M represents hydrogen, an alkali metal ion or an ammonium ion. n is 1 or 2. ), (b) General formula, [Formula] (where Ar is an aromatic cyclic group consisting of two or more benzene rings or heterocycles, and X is N ₃ ―
or N ₃ SO ₂ --, Y is a monovalent group selected from hydrogen, an alkyl group, an alkoxy group, a nitro group, a carboxyl group, a sulfonic acid group, and a halogen;
R ³ represents a divalent organic group connecting Ar and N, and R ⁴ and R ⁵ represent hydrogen or a lower alkyl group. ) and (c) a sensitizer added as necessary. 2. A patent characterized in that the amine compound [] is blended in a proportion of 0.01 equivalent or more and 5 equivalents or less with respect to the carboxyl group of the side chain of the polymer [] or the group represented by its anion. A photosensitive polymer composition according to claim 1.