JPH0368066B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for forming a polyimide pattern with excellent heat resistance using a novel photosensitive polymer composition that is a heat-resistant polymer. Conventionally, as a photosensitive polymer composition that becomes a heat-resistant polymer, (a) a polymer whose main component is polyamic acid, which is a precursor of polyimide, and a carbon-carbon double bond that can be dimerized or polymerized by actinic radiation; (b) A system in which a group (vinyl group) having an unsaturated bond is introduced into the carboxyl group of polyamic acid through an amide bond, and a bisazide compound is added. A photosensitive heat-resistant polymer composition is known. However, the composition (a) above has a sensitivity of several hundred to several thousand
mJ/ ^cm2 , which is insufficient for practical use, and the composition (b) above not only does not form a fine pattern because the pattern in the exposed area is easily eluted during development, but also the end surface of the pattern. There was a drawback that the image was not clear. An object of the present invention is to eliminate the drawbacks of the prior art described above and to provide a method for forming patterns on polyimide using a photosensitive polymer composition with high sensitivity and good resolution. As a result of intensive study to achieve the above objectives, (i) General formula (However, in the [formula], R ¹ represents a trivalent or tetravalent organic group, R ² represents a divalent organic group, and n is 1 or 2.) 100 parts by weight, (ii) general formula [However, in the formula [), X is -OH, -OR ³ , -R ⁴
−OH, −SiR ³ ₃ , −COOH, −COOR ³ , −NR ² ₃ , −
NH ² , (R ³ is a lower alkyl group, R ⁴ is an alkylene), m is 0
or 1. ] 0.1 to 100 parts by weight of an aromatic bisazide compound represented by (iii) general formula (However, R ⁵ , R ⁶ , R ⁷ , and R ⁹ are hydrogen, a group selected from a lower alkyl group, a phenyl group, and a vinyl group, and R ⁸ is an alkylene.) It has been found that a photosensitive polymer composition consisting of parts by weight and (iv) a sensitizer added as necessary has higher sensitivity and better resolution than the conventional method described above. The photosensitive polymer composition used in the pattern forming method of the present invention is usually formed as a coating film on a target substrate, and then irradiated with actinic radiation such as ultraviolet rays at desired locations to remove unirradiated areas and irradiated areas. By creating a difference in the solubility of the polymer composition in the solvent and treating it with a developer (solvent), a desired negative pattern made of the polymer composition can be obtained. It is believed that the above pattern forming method is based on the fact that when actinic radiation is irradiated, a photocrosslinking reaction occurs in the light-receiving portion, forming crosslinks between the polymers, thereby increasing the insolubility in solvents. The present photosensitive polymer composition uses a bisazide compound known to have high photoreactivity as a photocrosslinking agent in order to cause this photocrosslinking reaction. When the azide group (-N ₃ ) of this bisazide compound absorbs light, it forms the active species nitrene (-N:), which is capable of adding to double bonds, inserting into C-H bonds, hydrogen abstraction reactions, etc. to form a bond. By having this azide group at both ends of the molecule, bisazide compounds can form chemical bonds at both ends of the molecule, and therefore can participate in crosslinking of polymers, but polyamic acids represented by the formula [] The active species does not have a reactive group with nitrene. Therefore, in this photosensitive polymer composition, the third component has a group (amino group) that binds to polyamic acid and reacts efficiently with the active species nitrene (carbon-carbon double bond, C -H group, etc.) to enable crosslinking with polyamic acid. At this time, it is thought that the compound used as the third component is incorporated into the polyamic acid by ionic bonding of its amino group with the carboxyl group of the polyamic acid. It is based on the following experimental examples that the bisazide compound used in addition to the polyamic acid and the amine compound having a reactive group with nitrene are essential components, and therefore the above reaction is considered to be the main reaction for crosslinking. 3'-(N,N-dimethylamino)propyl-3-butenecarboxylate in an equimolar amount relative to the number of moles of carboxyl groups in the polyamic acid, and 2,6-di(4'- azidobenzal)-4-
The photosensitive polymer composition to which hydroxycyclohexanone has been added has a coating thickness of 4 μm, and is irradiated using a 350W high-pressure mercury lamp and 30 cm from the light source through a photomask.
When irradiated with light at a distance of In case of acid only, in case of composition using two components of polyamic acid and bisazide or polyamic acid and amine compound,
Even when irradiated with light for 15 minutes under exactly the same experimental conditions as above, no pattern was formed and the coating film was completely dissolved in the developer. In a system consisting of a polyamic acid and an amine compound, even if the amine compound has a double bond that undergoes photoreaction (dimerization, polymerization, etc.), if a bisazide compound coexists, the active species generated overwhelmingly from the bisazide. The main reaction is the crosslinking reaction due to the addition of nitrene. For example, polyamic acid and 2-(N,
The composition consisting of N-dimethylamino)ethyl methacrylate has a sensitivity (irradiation dose that reduces the thickness of the coated film to 1/2 after development) of 3200 mJ/cm ² under the above irradiation conditions.
However, with respect to the number of moles of the amine component,
0.1 times the mole of 2,6-di(4'-azidobenzal)-
The photosensitive polymer composition containing 4-hydroxycyclohexanone has a sensitivity of 40 mJ/ ^cm2 , compared to 1.3 of the former.
It became possible to form patterns with % irradiation dose. That is,
This means that the photodecomposition of nitrene in the bisazide compound and its subsequent addition to the double bond occur in an extremely short time and with high efficiency. In order to make the photosensitive polymer composition used in the pattern forming method of the present invention practical and highly sensitive, the above-mentioned photosensitizing component itself has also been modified. Conventionally, for materials that are based on low polarity polymers such as rubber polymers as the photosensitizer component of photoresist materials, bisazide compounds (for example, 2,6-bis-(paraazidobenzal)-
Although a method using bisazide compound (4-methylcyclohexanone) is known, there is no known example of producing a product using a bisazide compound in a highly polar polyamic acid. This is because the bisazide compound has low compatibility with polyamic acid, so the bisazide compound may precipitate when forming a coating film, and the solubility of polyamic acid in solvents (polar solvents) is low, so there is a limit to the amount that can be added. This is because high sensitivity cannot be obtained. In the present invention, in order to solve the above-mentioned compatibility and solubility, it was thought that it would be sufficient to use a bisazide compound having a polar substituent to enhance the interaction with the polyamic acid and the polar solvent. In addition, in the case of reactions in films, it is believed that the proximity of the reacting species to each other and their high mobility are factors that increase the reaction efficiency.
From this point of view as well, we thought that it would be better to use a polar photosensitizing component that has good compatibility with polyamic acid. In accordance with the above idea, the photosensitive polymer composition of the present invention uses a compound represented by the general formula [ ] having a polar group at the 4-position of the cyclohexanone ring as the bisazide compound, and a polar ester group as the amine component. By using a compound represented by the general formula [], we were able to create a material with excellent coating film-forming ability and high sensitivity of several to several tens of mJ/ ^cm2 . The materials used in the present invention will be explained below. The polyamic acid represented by the general formula [] can be converted into polyimide by heat treatment,
These polyimides have heat resistance. The polymer having the repeating unit represented by the general formula [] as a main component may consist only of the polyamic acid represented by the general formula [], or may be a copolymer of this and other repeating units. Examples of these include polyesteramic acid, polyhydrazideamic 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° C. for 1 hour in a nitrogen atmosphere. R ¹ and R ² in the general formula [] are preferably an aromatic ring-containing organic group or a heterocyclic-containing organic group from the viewpoint of heat resistance when formed into a polyimide. Examples of these are USP3, 179,
614, USP 3, 740, 305, and Special Publication No. 1983-2956. However, the material is not limited to these as long as it imparts heat resistance to polyimide. Specifically, R ¹ is

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[Formula] (In the formula, the bond represents a bond with the carboxyl group of the polymer main chain, and the carboxyl group is located at the ortho position to the bond.). Specifically, R ² is

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[Formula] etc. 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. Preferred polyamic acids represented by the general formula [] include pyromellitic dianhydride, 4,4'-diaminodiphenyl ether, pyromellitic dianhydride, and 3,3',4,4'-benzophenyl ether. Nontetracarboxylic dianhydride and 4,4' diaminodiphenyl ether, pyromellitic dianhydride and 3,3',4,4'-benzophenonetetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether enyl ether and 3,3',4,4'-benzophenonetetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether-3-carboxamide, pyromellitic dianhydride and 3,3',4, Examples include polyamic acids derived from 4'-benzophenonetetracarboxylic dianhydride, 4,4'-diaminodiphenyl ether, and bis(3-aminopropyl)tetramethyldisiloxane. As mentioned above, the polyamic acid represented by the general formula [] is usually obtained by reacting a diamine compound with an acid dianhydride in an approximately equimolar amount,
As the reaction solvent used in this case, an aprotic polar solvent is preferably used from the viewpoint of solubility of the reaction substrate and the polyamic acid to be produced. Typical examples include N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, N-acetyl-ε-caprolactam and 1,3-dimethyl-2-imidazolidinone. It is mentioned as. As a bisazide compound represented by the general formula [] Suitable examples include, but are not limited to, the following. The blending ratio of the bisazide compound represented by the general formula [] is preferably 0.1 parts by weight or more and 100 parts by weight or less, more preferably 0.1 parts by weight or more and 100 parts by weight or less, based on 100 parts by weight of the polymer whose main component is a repeating unit represented by the general formula []. teeth
It is preferably used in an amount of 0.5 parts by weight or more and 50 parts by weight or less. If it deviates from this range, it will adversely affect the storage stability of the developable varnish. The amine compounds represented by the general formula [] include 2-(N,N-dimethylamino)ethyl acrylate, 2-(N,N-dimethylamino)ethyl methacrylate, and 3-(N,N-dimethylamino)
Propyl acrylate, 3-(N,N-dimethylamino)propyl methacrylate, 4-(N,N
-dimethylamino)butyl acrylate, 4-
(N,N-dimethylamino)butyl methacrylate, 5-(N,N-dimethylamino)pentyl acrylate, 5-(N,N-dimethylamino)pentyl methacrylate, 6-(N,N-dimethylamino)hexyl acrylate , 6-(N,N-dimethylamino)hexyl methacrylate, 2-
(N,N-dimethylamino)ethylcinnamate,
Preferred examples include 3-(N,N-dimethylamino)propyl cinnamate, but are not limited to these as long as they react efficiently with bisazide []. The compounding ratio of the amine compound [] is the general formula []
A polymer whose main component is a repeating unit represented by
It is used in an amount of 1 part by weight or more and 400 parts by weight or less per 100 parts by weight, preferably 10 parts by weight or more and 400 parts by weight or less. If you deviate from the above range,
This has an adverse effect on developability and the quality of the polyimide film in the final product. The photosensitive polymer composition according to the present invention is used in the form of a solution in which the above-mentioned 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; −
2-pyrrolidone, N-acetyl-2-pyrrolidone, N-benzyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphortriamide, N-acetyl-ε-caprolactam , dimethylimidazolidinone and the like. These may be used alone or in combination. The amount of solvent is based on 100 parts by weight of the polymer whose main component is a repeating unit represented by the general formula [], the bisazide compound represented by the general formula [], and the amine compound represented by the general formula []. It is preferable to use 100 parts by weight or more and 10,000 parts by weight or less,
More preferably, it is used in an amount of 200 parts by weight or more and 5,000 parts by weight or less; deviations from this range will affect film-forming properties. A sensitizer may be appropriately added to the above composition for the purpose of improving sensitivity, but the amount of addition is limited to a polymer whose main component is a repeating unit represented by the general formula [], a bisazide represented by the general formula [] 0.1 part by weight or more of the total weight of the compound, amine compound10
It is desirable to use it in an amount of less than 1 part by weight, and if it is outside this range, it will have an adverse effect on the developability and the heat resistance of the final polyimide product. Compounds that are effective for sensitizing aromatic bisazide compounds are Tsunoda and Yamaoka [Phot.Sci.Eng., 17-, 390 (1973)]
It has been reported in detail by et al. Among them, anthrone, 1,9-benzanthrone, acridine, cyanoacridine, nitropyrene, 1,8-
Dinitropyrene, Mihiraketone, 5-nitroacenaphthene, 2-nitrofluorene, pyrene-1,
Preferred are 6-quinone, 9-fluorenone, 1,2-benzanthraquinone, anthantrone, 2-chloro-1,2-benzanthraquinone, 2-promobenzanthraquinone, 2-chloro-1,8-phthaloylnaphthalene, and the like. In order to improve the adhesion between the coating film of the photosensitive polymer composition or the heat-cured polyimide film and the supporting substrate in the step of the pattern forming method of the present invention, the supporting substrate may be appropriately treated with an adhesion aid. . Support substrates include metals, glass, semiconductors, metal oxide insulators (e.g. TiO ₂ , Ta ₂ O ₅ , SiO ₂
), silicon nitride, etc. 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, and spray printing, which can be selected as appropriate. The thickness of the coating film, the coating method, the solid content concentration of the varnish of the present polymer composition,
It can be adjusted by adjusting the viscosity, etc. A relief pattern is obtained by irradiating the photosensitive polymer composition of the present invention in the form of a coating on a support substrate with ultraviolet rays, and then dissolving and removing the unexposed areas with a developer. As a developer, N-methyl-2-pyrrolidone,
N-acetyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphortriamide, dimethylimidazolidinone, N-
Benzyl-2-pyrrolidone, N-acetyl-ε-
An aprotic polar solvent such as caprolactam can be used alone or as a mixture with a non-solvent for polyamic acid such as methanol, ethanol, isopropyl alcohol, benzene, toluene xylene, 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 methylene cellosolve. The relief pattern polymer obtained by the above treatment is a precursor of polyimide, and
By processing at a heating temperature selected from a range of 450°C to 450°C, relief patterns of heat-resistant polymers containing imide rings and other cyclic groups are obtained. 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 1791 g of 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 by ice-cooling, 109 g of pyromellitic dianhydride was added while stirring.
(0.5 mol) was added. Approximately 15 more after adding
Polyamic acid with a viscosity of 60 poise (30°C) was obtained by reacting at ℃ for 3 hours. A solution (A) was obtained. To 20g of the solution (A) obtained above, (N,N-
Dimethylamino)ethyl methacrylate 0.79g
(0.005 mol), 2,6-di(4'-azidobenzal)
-4-Hydroxycyclohesaquinone 0.74g
(0.002 mol) 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.
A coating film with a thickness of 2 μm was obtained. This coating was closely covered with a striped soda glass photomask, and a 500W Xe
-Ultraviolet irradiation was performed using a Hg lamp. The intensity of ultraviolet light at the light receiving surface was 8 mW/cm ² at a wavelength of 365 nm. After exposure,
4 volumes of N-methyl-2-pyrrolidone, 1 volume of ethanol
A relief pattern with a minimum line width of 2 μm was obtained by developing with a mixed solution consisting of 2 μm and then rinsing with ethanol. The sensitivity (the dose at which the film thickness after development is 1/2 of the initial thickness) is 40 mJ/ ^cm2 , and no pattern blurring was observed even when the resulting pattern was heated at 400°C for 60 minutes. Ta. Example 2 90 g (0.45 mol) of 4,4'-diaminodiphenyl ether and 9.6 g (0.05 mol) of bis(3-aminopropyl)tetramethyldisiloxane under nitrogen flow.
was dissolved in 1765 g of N-methyl-2-pyrrolidone,
An amine solution was prepared. Next, while keeping this solution at a temperature of about 15°C by ice-cooling, 54.5 g (0.25 mol) of pyromellitic dianhydride, 3,3',
4,4'-Benzophenonetetracarboxylic acid dihydrate
80.5 g (0.25 mol) was added. After the addition, the reaction was continued for 3 hours at approximately 15°C until the viscosity was 50 poise (30
°C) polyamic acid

[Formula] (However, R ¹⁹ is

[Formula] and

[Formula] is 1:1, R ²⁰ is

[Formula] and A solution (B) of 9:1) was obtained. 2-(N,
N-dimethylamino)ethyl methacrylate 1.57
g (0.01 mol), 2.6-di(4'-azidocinnamylidene)-4-hydroxycyclohexanone 0.42
(0.001 mol) 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 3.3 μm. This coating was closely covered with a striped soda glass photomask, irradiated with ultraviolet light using a 500W high-pressure mercury lamp, developed with a mixture of 5 volumes of N-methyl-2-pyrrolidone and 1 volume of ethanol, and washed with ethanol. A relief pattern with a minimum line width of 6 μm was obtained. The sensitivity is 35mJ/ ^cm2 ,
Even when the obtained pattern was heated at 400°C for 60 minutes, no blurring of the pattern was observed. The formed polyimide film had improved adhesion to the substrate. Example 3 90 g (0.45 mol) of 4,4'-diaminodiphenyl ether, 1.14 g (0.05 mol) of 4,4'-diaminodiphenyl ether-3-carbonamide under a nitrogen stream
mol) in 1764 g of N-methyl-2-pyrrolidone to prepare an amine solution. Next, while keeping this solution at a temperature of about 15°C by ice-cooling, 54.5 g (0.25 mol) of pyromellitic dianhydride was added to the solution while stirring.
80.5 g (0.25 mol) of 3,3',4,4'-benzophenonetetracarboxylic dianhydride was added. After the addition is complete, let the reaction continue for 3 hours at approximately 15°C to reduce the viscosity.
55 poise (30℃) polyamic acid (However, R ¹⁷ is

[Formula] and

[Formula] is 1:1, R ¹⁸ is

[Formula] and

A solution (C) having the formula of 9:1 was obtained. 3-(N,
N-dimethylamino)propyl methacrylate
1.71g (0.01mol), 2,6-di(4'-azidobenzal)-4-hydroxycyclohexanone 0.37g
(0.001 mol) was dissolved and then filtered under pressure using a 1 μm pore filter. The resulting solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to form a 5.2 μm layer.
A thick coating film was obtained. This coating film was closely covered with a striped soda glass photomask, and a 500W high-pressure mercury lamp (light intensity at the light receiving surface was 4mW at a wavelength of 365nm) was used.
cm ² ) and developed with a mixture of 4 volumes of N-methyl-2-pyrrolidone and 1 volume of ethanol.
It was then rinsed with ethanol to obtain a relief pattern with a minimum line width of 6 μm. The sensitivity was 8 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 4 To 20 g of the solution (C) obtained in Example 3, 3-(N,N
-dimethylamino)propyl methacrylate 1.71
g (0.01 mol), 2,6-di(4'-azidobenzal)-4-methoxycyclohexanone 0.39 g
(0.001 mol) was dissolved and then filtered under pressure using a 1 μm pore filter. The resulting solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to form a 4.9 μm layer.
A thick coating film was obtained. This coating film was closely covered with a striped soda glass photomask, and a 500W high-pressure mercury lamp (light intensity at the light receiving surface was 4mW at a wavelength of 365nm) was used.
cm ² ) and developed with a mixture of 4 volumes of N-methyl-2-pyrrolidone and 1 volume of ethanol.
It was then rinsed with ethanol to obtain a relief pattern with a minimum line width of 6 μm. The sensitivity was 15 mJ/cm ² , and no blurring of the pattern was observed even when the resulting pattern was heated to 400° C. for 60 minutes. Example 5 To 20 g of the solution (C) obtained in Example 3, 3-(N,N
-dimethylamino)propyl methacrylate,
1.71g (0.01mol), 2,6-di(4'azidobenzal)-4-methylolcyclohexanone 0.39g
(0.001 mol) was dissolved and then filtered under pressure using a 1 μm pore filter. The resulting solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to form a 5.2 μm layer.
A thick coating film was obtained. This coating film was closely covered with a striped soda glass photomask, and a 500W high-pressure mercury lamp (light intensity at the light receiving surface was 4mW at a wavelength of 365nm) was used.
cm ² ) and developed with a mixture of 4 volumes of N-methyl-2-pyrrolidone and 1 volume of ethanol.
It was then rinsed with ethanol to obtain a relief pattern with a minimum line width of 6 μm. The sensitivity was 7 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 6 3-(N,N
-dimethylamino)propyl methacrylate 1.71
g (0.01 mol), 2,6-di(4'azidobenzal)
-4-Carboxycyclohexane 0.04g (0.001
mol) was dissolved and then filtered under pressure using a 1 μm pore filter. The resulting solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to form a 5.0 μm layer.
A thick coating film was obtained. This coating was closely covered with a striped soda glass photomask, and a 500W high-pressure mercury lamp (the light intensity at the light receiving surface was at a wavelength of 365nm) was used.
N-methyl- ^2-
Develop with a mixture of 3 volumes of pyrrolidone and 2 volumes of methanol, then rinse with ethanol to minimize line width.
A relief pattern of 5 μm was obtained. Sensitivity is 6mJ/
^cm2 , and no blurring of the pattern was observed even after heating at 400°C for 60 minutes. Example 7 To 20 g of the solution (C) obtained in Example 3, 3-(N,N
-dimethylamino)propyl methacrylate 1.71
g (0.01 mol), 2,6-di(4'-azidobenzal)-4-trimethylsilylcyclohexanone
0.43 g (0.001 mol) was dissolved and then filtered under pressure using a 1 μm pore filter. The resulting solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to form a 5.3 μm layer.
A thick coating film was obtained. This coating was closely covered with a striped soda mask and a glass photomask, and a 500W high-pressure mercury lamp (the light intensity at the light receiving surface was at a wavelength of 365 nm) was used.
N-methyl- ^2-
Develop with a mixture of 4 volumes of pyrrolidone and 1 volume of methanol, then rinse with ethanol to minimize line width.
A relief pattern of 6 μm was obtained. The sensitivity is
10mJ/ ^cm2 , and the resulting pattern was 60mJ/cm2 at 400℃.
No blurring of the pattern was observed even after heating for several minutes. Example 8 To 20 g of the solution (C) obtained in Example 3, 4-(N,N
-dimethylamino)butyl methacrylate 1.85g
(0.01 mol), 2,6-di(4'-azidobenzal)
-4-hydroxycyclohexanone 0.37g
(0.001 mol) was dissolved and then filtered under pressure using a 1 μm pore filter. The resulting solution was spin-coated onto a silicon wafer using a spinner, and then dried at 70°C for 30 minutes to form a 4.7 μm layer.
A thick coating film was obtained. This coating was closely covered with a striped soda glass photomask, and a 500W high-pressure mercury lamp (the light intensity at the light receiving surface was at a wavelength of 365nm) was used.
N-methyl- ^2-
Develop with a mixture of 4 volumes of pyrrolidone and 1 volume of ethanol, then rinse with ethanol to
A relief pattern of 5 μm was obtained. Sensitivity is 6mJ/
^cm2 , and no blurring of the pattern was observed even when the resulting pattern was heated at 400°C for 60 minutes. Comparative Example 1 Experimental results obtained by adding a carbon-carbon double bond, an amino group, or a quaternized salt thereof that can be dimerized or polymerized by actinic radiation to a polymer mainly composed of polyamic acid are 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 soda glass photomask and exposed to ultraviolet light using a 500W high-pressure mercury lamp. After exposure, it was developed with a mixture of 5 volumes of N,N-dimethylacetamide and 1 volume of ethanol, and then washed with ethanol to obtain a relief pattern. The sensitivity is 3200mJ/ ^cm2 ,
The sensitivity was low compared to any of Examples 1 to 8. Comparative Example 2 The experimental results of a photosensitive heat-resistant polymer composition consisting of a system in which a group (vinyl group) having an unsaturated bond through an amide bond is introduced into the carboxyl group of polyamic acid and a bisazide compound is added are shown below as a comparative example. Shown as A three-necked flask equipped with a stirring bar, a cooling tube, a calcium chloride tube, and a gas introduction tube was heated under a nitrogen stream for 4 days.
Add 2.0 g (0.01 mol) of 4'-diaminodiphenyl ether and dissolve with 25 g of N-methyl-2-pyrrolidone. Next, cool the melter on ice and gradually add 2.2 g (0.01 mol) of pyromellitic anhydride while keeping the temperature below 5℃.
After the mixture was completely dissolved, the mixture was returned to room temperature and stirred for 5 hours. Add triethylamine 2 to the obtained polymer solution.
g (0.02 mol) and 7.0 g (0.02 mol) of hexachlorocyclotriphosphatriazene were added to
The mixture was stirred for an hour, and then 6.8 g (0.12 mol) of allylamine was added and stirred at room temperature for 3 hours. 1.5 g of 4,4'-diazidostilbene was added to this solution to prepare a photosensitive polyamic acid varnish. This varnish was spin-coated onto a glass plate, dried, and exposed using a 500W high-pressure mercury lamp using a striped mask.
- When developed with pyrrolidone and rinsed with ethanol, the masked areas were soluble in the solvent, and the unmasked areas were insoluble. The resolution was significantly lower than in Examples 1 to 8, the end faces of the relief patterns obtained were wavy, and the resolution was only a pattern with a minimum line width of 1000 μm. As described above, according to the polyimide pattern forming method using the composition according to the present invention, it is possible to improve the photosensitivity and resolution of the photosensitive film and the heat resistance and mechanical properties of the polyimide film finally obtained. It becomes possible to improve the characteristics. The polyimide pattern forming method using the photosensitive polymer composition of the present invention is applied to interlayer insulating films for semiconductor multilayer wiring, heat-resistant photoresists, and the like.

Claims (1)

[Claims] 1 (i) General formula (However, in the [formula], R ¹ represents a trivalent or tetravalent organic group, R ² represents a divalent organic group, and n is 1 or 2.) 100 parts by weight, (ii) general formula (However, in the formula [), X is -OH, -OR ³ , -R ⁴
−OH, −SiR ³ ₃ , −COOH, −COOR ³ , −NR ² ₃ , −
NH ₂ , (R ³ is a lower alkyl group, R ⁴ is an alkylene), and m is 0 or 1. ) 0.1 to 100 parts by weight of an aromatic bisazide compound represented by (iii) general formula (However, in the formula [], R ⁵ , R ⁶ , R ⁷ , R ⁹ are hydrogen,
A group selected from a lower alkyl group, a phenyl group, a vinyl group, and R ⁸ represents an alkylene group. )
A solution of a composition consisting of 1 to 400 parts by weight of an amine compound represented by is applied onto a substrate and dried to form a film, and the film is exposed to light with a mercury lamp through a photomask having a desired pattern, and A pattern forming method characterized by forming a polyimide pattern with excellent heat resistance through development and heat treatment. 2. The pattern forming method according to claim 1, wherein a sensitizer is added to the solution of the composition.