JPH0844060A - Production of photosensitive resin composition and pattern - Google Patents

Abstract

PURPOSE:To produce a photosensitive resin composition capable of obtaining a coated film uniform in film thickness without a secular change of varnish. CONSTITUTION:In this composition, (a) 100 pts.wt. polymer consisting essentially of a repeating unit expressed by formula I (where the formula, R<1> is tervalent or quadrivalent org. group, R<2> is divalent org. group, M is alkali metal ion or ammonium ion. (n) is 1 or 2.), (b) 0. 1-100 pts.wt. bisazido compd. expressed by formula II (where, the formula, R<3> is divalent org. group.), (c) 1-400 pts.wt. amine compd. having an unsatd. bond and (d) a compd. having carboxyl group in a molecule are incorporated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel photosensitive resin composition which becomes a heat resistant polymer and a method for producing a pattern.

[0002]

2. Description of the Related Art In recent years, in the field of semiconductor industry, polyimide resins have been used for protection films of integrated circuits and interlayer insulating films for multilayer wiring. Further, recently, various methods have been attempted to impart a pattern forming ability such as a photoresist to a polyamic acid (polyimide prepolymer) to form a photosensitive polyimide precursor and to rationalize the pattern forming process. The photosensitive polyimide precursor is required to have a photosensitive property as a photoresist and an insulating property as a permanently used film, and various materials have been proposed, but it is difficult to obtain a particularly sensitive material. It was This is because there are many factors that suppress high photoreactivity, such as storage stability of polyamic acid, high glass transition temperature, light absorption in the near-ultraviolet region, and restrictions on the introduction rate of the photosensitive group (or photosensitizer).

[0003]

It has been found that a method using a bisazide compound as a photosensitizer has an extremely high sensitivity, and the above problems have been solved by this method.
Along with the aging of the varnish, a new problem arises that a coating film having a uniform film thickness cannot be obtained in the coating process. The present invention provides a photosensitive resin composition which does not cause unevenness in film thickness in a coating process, and a method for producing a pattern using this composition.

[0004]

The present invention provides (a) general formula (1)

[Chemical 3] (Wherein R ¹ is a trivalent or tetravalent organic group, R ² is a divalent organic group, M is hydrogen, an alkali metal ion or an ammonium ion, and n is 1 or 2). 100 parts by weight of a polymer having a repeating unit as a main component, (b) general formula (2)

[Chemical 4] (Wherein R ³ represents a divalent organic group) 0.1 to 100 parts by weight, (c) 1 to 400 parts by weight of an amine compound having an unsaturated bond, and (d) intramolecular The present invention relates to a photosensitive resin composition containing a compound having a carboxyl group and a method for producing a pattern using this composition.

The photosensitive resin composition of the present invention is applied in the form of a varnish. As a coating method, spin coating is generally used, but dip coating, spray coating, printing or the like may be used. The varnish applied is heated and dried for the purpose of evaporating the solvent. The heating temperature is selected from a temperature range of room temperature or higher and 120 ° C. or lower. If it is lower than room temperature, the evaporation rate of the solvent is slow and it is not practical. If it exceeds 120 ° C., the photosensitive resin composition causes a dark reaction and loses the photosensitivity or the sensitivity is extremely deteriorated, so that it cannot be put to practical use. When heating and drying at 40 ° C. or lower, it is effective to perform vacuum or blast drying.
Next, ultraviolet rays are irradiated through a predetermined photomask to print the pattern. Ultraviolet rays that have a spectral distribution emitted from a high-pressure mercury lamp are usually used.
UV intensity at the wavelength of 0.1 to 50 on the sample irradiation surface
Those of mW / cm ² are preferably used.

A relief pattern is obtained by developing the printed pattern. As the developing solution, N-methyl-2-pyrrolidone, N-acetyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphortriamide, dimethylimidazolidinone, N -Aprotic polar solvent such as benzyl-2-pyrrolidone and N-acetyl-ε-caprolactam alone or with a non-solvent of polyamic acid such as methanol, ethanol, isopropyl alcohol, benzene, toluene, xylene, methyl cellosolve and water. Can be used as a mixed solution of. The relief pattern formed by development is then washed with a rinse solution to remove the development solvent. As the rinse liquid, a solvent that has good miscibility with the developer and serves as a poor solvent for the polyamic acid is used. Specifically, methanol, ethanol, isopropyl alcohol, water,
Benzene, toluene, xylene, acetone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, dioxane, methyl cellosolve, ethyl cellosolve, butyl carbitol, butyl carbitol acetate, ethyl acetate, butyl acetate, etc. may be used alone or in combination of two or more. Development and rinsing can be carried out by dipping or spraying at room temperature for 0.5 to 5 minutes. After the rinse, most of the rinse liquid is removed by spin drying or blow drying.

Next, the remaining rinse liquid is heated and dried to evaporate, and at the same time, a conversion reaction from polyamic acid to polyimide is caused. At this time, the bisazide compound, the amine compound and the compound having a carboxyl group in the molecule used for imparting photosensitivity scatter from the film.
The heat treatment temperature is in the range of 150 ° C to 500 ° C. If the temperature is lower than 150 ° C., the imidization reaction does not effectively occur or the bisazide compound, the amine compound and the compound having a carboxyl group are not sufficiently scattered. If the temperature is higher than 500 ° C, the polymer is decomposed. When the heat treatment temperature is 300 ° C. or higher, an inert gas atmosphere such as N ₂ or vacuum heating is used to give good results.

The photosensitive resin composition used in the present invention will be described. The polymer containing a repeating unit represented by the general formula (1) as a main component may be composed of only the repeating unit represented by the general formula (1) or may contain this and other repeating units. It is desirable to select the type and amount of other repeating units within a range that does not significantly impair the heat resistance of the polyimide obtained by the final heat treatment. R ¹ and R ² in the general formula (1) are preferably aromatic ring-containing organic groups and heterocyclic ring-containing organic groups from the viewpoint of heat resistance when used as a polyimide.

R ¹ is specifically

Embedded image (In the formula, the bond represents only the bond with the carbonyl group of the polymer main chain, and the carboxyl group or the like bonded to R ₁ is located at the ortho position with respect to the bond).

R ² is specifically

[Chemical 6] And the like.

Further, R ¹ and R ² may have a substituent such as a halogen atom, an amino group, an amide group, a carboxyl group and a sulfonic acid group as long as the heat resistance of the polyimide is not adversely affected.

As the polymer represented by the general formula (1), pyromellitic dianhydride, 4,4'-diaminodiphenyl ether, pyromellitic dianhydride and 3,3 ',
4,4'-benzophenone tetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether, pyromellitic dianhydride and 3,3 ', 4,4'-benzophenone tetracarboxylic acid and 4,4'-diaminodiphenyl ether And 4,4'-diaminodiphenyl ether-3
-Carboxamide, pyromellitic dianhydride and 3,
Examples thereof include polyamic acid derived from 3 ', 4,4'-benzophenone tetracarboxylic dianhydride, 4,4'-diaminodiphenyl ether and bis (3-aminopropyl) tetramethyldisiloxane.

As described above, the polymer represented by the general formula (1) is usually obtained by reacting a diamine compound with an acid dianhydride in an approximately equimolar amount. The reaction solvent used in this case is a reaction material. And N-methyl-2-pyrrolidone, N, N-dimethylformamide, dimethyl sulfoxide, hexamethylphosphoric triamide and
Aprotic polar solvents such as 3-dimethyl-2-imidazolidinone are preferred.

Examples of the bisazide compound represented by the general formula (2) include

[Chemical 7] {Wherein X is -N ₃ or -SO ₂ N _3, R ⁴ is -H, a lower alkyl _{group, -OH, -OCH 3, -COOH,} -SO
Groups selected from ₃ H, —NO ₂ and halogen, R ⁵ , R ⁶
And R ⁷ is alkylene, —SO ₂ —, —S—, —O—,
-NH-,

Embedded image (R ¹⁰ represents alkylene),

[Chemical 9] (K is 1 to 10), R ⁸ is —O.
H, -OR ⁹ ,

[Chemical 10] A group selected from —COOH and —COOR ⁹ (R ⁹ is a lower alkyl group), and Y represents —O—, —S— and —N.
Examples thereof include a group selected from H-, m is 0 or 1, and the like, but a compound having an aromatic azide group at both ends of the molecule may be used.

Preferred bisazide compounds represented by the general formula (2) are:

[Chemical 11]

[Chemical 12]

[Chemical 13]

Embedded image And the like. It is preferable that the bisazide compound has good compatibility with the above-mentioned polyamic acid.

The blending ratio of the bisazide compound represented by the general formula (2) is 0.1 parts by weight or more and 100 parts by weight or less based on 100 parts by weight of the polymer containing the repeating unit represented by the general formula (1) as a main component. And 0.5 parts by weight or more 5
It is preferably used in an amount of 0 parts by weight or less. If it deviates from this range, the developability and the storage stability of the varnish are adversely affected.

Examples of amine compounds having an unsaturated bond include:

[Chemical 15] Etc. are mentioned as a suitable example. These compounds react efficiently with the above bisazide compounds. The compounding ratio of the amine compound is 1 with respect to 100 parts by weight of the polymer containing the repeating unit represented by the general formula (1) as a main component.
The content is set to be not less than 400 parts by weight but preferably not less than 10 parts and not more than 400 parts by weight.

Examples of the compound having a carboxyl group in the molecule include formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid and oxalic acid, but are not limited thereto. The compounding ratio of this compound is preferably 100 parts by weight or less, more preferably 0.5 parts by weight or more and 5 parts by weight, relative to 100 parts by weight of the polymer containing the repeating unit represented by the general formula (1) as a main component.
It is used in an amount of 0 parts by weight or less. If this compound is used in excess of 100 parts by weight, this compound will precipitate, which is not preferable.

The photosensitive resin composition according to the present invention is used in a solution state in which the above-mentioned constituents are dissolved in a suitable polar solvent or the like. The amount of the solvent is mainly the repeating unit represented by the general formula (1) in view of film-forming property. The total amount of the component polymer, the bisazide compound represented by the general formula (2), the amine compound having an unsaturated bond, and the compound having a carboxyl group in the molecule is 100 parts by weight or more and 100 parts by weight or more and 10000 parts by weight or less. Is preferred, and 200 parts by weight or more and 5000
It is more preferable to use less than 1 part by weight. Examples of the solvent include acetone, methyl ethyl ketone, toluene,
Chloroform, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, xylene, tetrahydrofuran, dioxane, N, N-dimethylacetamide, N, N-dimethylformamide,
N-methyl-2-pyrrolidone, γ-butyrolactone, dimethyl sulfoxide, ethylene carbonate, propylene carbonate, sulfolane and the like are used.

The photosensitive resin composition of the present invention can be used to produce a pattern by an ordinary fine processing technique. For applying the present composition to a substrate, means such as spin coating using a spinner, dipping, and spray printing can be used, and can be appropriately selected. The coating film thickness can be adjusted by the coating means, the solid content concentration of the varnish of the present composition, the viscosity, and the like. As the base material,
Metals, glass, semiconductors, metal oxide insulators (eg T
iO ₂ , Ta ₂ O ₅ , SiO _{2 and the} like), silicon nitride and the like. In the method for producing a pattern of the present invention, the base material may be treated with an adhesion aid in order to improve the adhesiveness between the coating film of the photosensitive resin composition or the polyimide coating after heat curing and the supporting substrate. Usually, the photosensitive resin composition of the present invention, which is dried on a hot plate at 50 to 150 ° C. to form a coating film on a substrate, is irradiated with ultraviolet rays to be exposed, and then the unexposed portion is dissolved and removed with a developing solution. Then, a pattern is obtained by developing. There are no particular restrictions on the conditions of exposure and development. 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
An aprotic polar solvent such as -acetyl-ε-caprolactam can be used alone or as a mixed solution with a non-solvent of a polyamic acid such as methanol, ethanol, isopropyl alcohol, benzene, toluene xylene and methyl cellosolve. The pattern formed by the development is then washed with a rinse solution to remove the development solvent. A non-solvent of polyamic acid having good miscibility with the developer is used as the rinse liquid, but methanol, ethanol, isopropyl alcohol, benzene, toluene, xylene,
Preferred examples include methylene cellosolve.
The polymer of the pattern obtained by the above treatment is a polyimide precursor, and by treatment at a heating temperature selected from the range of 150 ° C. to 450 ° C., a heat resistant polymer having an imide ring or other cyclic group can be obtained. It becomes a pattern.

An embodiment of the present invention will be described.

EXAMPLES The polymers used in the examples were obtained by the following production method. Benzophenone tetracarboxylic acid dianhydride, pyromellitic acid dianhydride, 4,4'-diaminodiphenyl ether and 3-aminocarbonyl-4,4'-diaminodiphenyl ether were mixed at a molar ratio of 1: 1: 4: 1 at room temperature to give 5 It was obtained by reacting in N-methyl-2-pyrrolidone for a period of time (No. 1). Pyromellitic dianhydride and diaminodiphenyl ether were equimolar for 5 hours at room temperature, N-methyl-
It was obtained by reaction in 2-pyrrolidone, NN-dimethylacetamide or 1,3-dimethyl-2-imidazolidinone (No. 2, No. 3, No. 4). Example 1 A photosensitive resin composition having the composition shown in No. 1 of Table 1 was spin-coated on a silicon wafer and dried at 70 ° C. for 30 minutes to form a coating film having a thickness of about 5 μm. When the film thickness of this coating film was measured by an interference film thickness meter, the coating film had a uniform film thickness. This coating film was exposed for 1 minute with a high pressure mercury lamp through a predetermined photomask. UV intensity at this time is 10 mW / cm ² (365 nm)
Met. Next, immersion development was carried out for 2 minutes at room temperature with a developer containing 90 g of N-methyl-2-pyrrolidone and 10 g of ion-exchanged water. Then, it was immersed in ethyl alcohol for 1 minute and rinsed. The film thickness here was about 4.5 μm, and no film thickness unevenness occurred.

Example 2 A photosensitive resin composition having the composition shown in No. 1 of Table 1 was used in the same manner as in Example 1 to form a coating film having a film thickness after exposure of about 5 μm in the same manner as in Example 1. Obtained. When the film thickness of this coating film was measured by an interference film thickness meter, the coating film had a uniform film thickness. Then N
-Methyl-2-pyrrolidone 75 g and ion-exchanged water 2
Immersion development was carried out for 2 minutes at room temperature using a developing solution consisting of 5 g, followed by immersion in ethyl alcohol for 1 minute for rinsing. The film thickness after rinsing was about 4.7 μm, and there was no film thickness unevenness.

Example 3 A photosensitive resin composition having the composition shown in Table 1 No. 1 was used in the same manner as in Example 1 to form a coating film having a film thickness after exposure of about 5 μm in the same manner as in Example 1. Obtained. When the film thickness of this coating film was measured by an interference film thickness meter, the coating film had a uniform film thickness. Then N
-Methyl-2-pyrrolidone 50 g and ion-exchanged water 5
Development was performed by a dipping method for 2 minutes at room temperature using 0 g of a developing solution, and then dipping in ethyl alcohol for 1 minute for rinsing. The film thickness after rinsing was about 4.6 μm, and the film thickness unevenness did not occur.

Example 4 A coating film having a film thickness after exposure of about 8 μm was obtained in the same manner as in Example 1 except that the photosensitive resin composition having the composition shown in No. 2 of Table 1 was used. When the film thickness of this coating film was measured by an interference film thickness meter, the coating film had a uniform film thickness. The exposed film was developed by a dipping method for 2 minutes at room temperature using a developing solution containing 75 g of N, N-dimethylacetamide and 25 g of ion-exchanged water, and then rinsed by dipping in acetone for 1 minute. The film thickness after rinsing was about 7 μm, and the film thickness unevenness did not occur.

Example 5 A photosensitive resin composition having the composition shown in No. 3 of Table 1 was used in the same manner as in Example 1 to obtain a coating film having a film thickness after exposure of about 4 μm. When the film thickness of this coating film was measured by an interference film thickness meter, the coating film had a uniform film thickness. This exposed coating is 1,3-
Development was performed by a dipping method for 2 minutes at room temperature using a developing solution containing 75 g of dimethyl-2-imidazolidinone and 25 g of ion-exchanged water, and then dipping for 1 minute in isopropyl alcohol for rinsing. The film thickness after rinsing is about 3.4 μm,
The film thickness unevenness did not occur.

Example 6 A coating film having a film thickness after exposure of about 4 μm was obtained in the same manner as in Example 1 except that the photosensitive resin composition having the composition shown in No. 4 of Table 1 was used. When the film thickness of this coating film was measured by an interference film thickness meter, the coating film had a uniform film thickness. The exposed film was developed by a dipping method for 2 minutes at room temperature using a developing solution containing 80 g of dimethylformamide and 20 g of ion-exchanged water, and then rinsed with methyl alcohol for 1 minute. The film thickness after rinsing was about 3.2 μm, and there was no film thickness unevenness.

Example 7 A coating film having a film thickness after exposure of about 4 μm was obtained in the same manner as in Example 1 except that the photosensitive resin composition having the composition shown in Table 4 No. 4 was used. When the film thickness of this coating film was measured by an interference film thickness meter, the coating film had a uniform film thickness. The exposed film was developed by a dipping method at room temperature for 2 minutes using a developing solution containing 80 g of dimethyl sulfoxide and 20 g of ion-exchanged water, and then dipped in methyl alcohol for 1 minute for rinsing. The film thickness after rinsing was about 3.3 μm, and the film thickness unevenness did not occur.

Comparative Example 1 A coating film obtained in the same manner as in Example 1 using a photosensitive resin composition having the composition shown in No. 1 of Table 1 but not containing acetic acid had uneven thickness. It was The exposed film was immersed in a developer containing 80 g of N, N-dimethylacetamide and 20 g of methyl alcohol at room temperature for 2 minutes to develop the film, and then immersed in methyl alcohol for 1 minute to rinse the film. There was uneven thickness.

[0029]

[Table 1]

By the photosensitive resin composition according to the present invention,
It is possible to obtain a coating film having a uniform film thickness, regardless of the change with time of the varnish.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location G03F 7/027 514 7/16 H01L 21/027

Claims (2)

[Claims] 1. (a) General formula (1): (Wherein R ¹ is a trivalent or tetravalent organic group, R ² is a divalent organic group, M is hydrogen, an alkali metal ion or an ammonium ion, and n is 1 or 2). 100 parts by weight of a polymer containing a repeating unit as a main component, (b) a general formula (2) (Wherein R ³ represents a divalent organic group) 0.1 to 100 parts by weight of (c) an amine compound having an unsaturated bond 1 to 400 parts by weight and (d) in the molecule A photosensitive resin composition comprising a compound having a carboxyl group. 2. A method for producing a pattern, which comprises coating the substrate with the photosensitive resin composition according to claim 1, drying, exposing, and developing.