JP2890491B2 - Actinic radiation sensitive polymer composition - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an actinic radiation-sensitive polymer composition, and more particularly, to obtaining a high residual film ratio at the time of exposure using a g-ray stepper. The present invention relates to a photosensitive polyimide composition which can be produced and has less coloring after heat treatment.

[Related Art] As a photosensitive polyimide composition, a composition obtained by adding 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, to polyamic acid (for example, JP-B-59-52822) or a polyimide precursor composition obtained by introducing a sensitivity to a polyamic acid with an ester group (for example, U.S. Pat. Nos. 3,957,512 and 4,408,831).
No. specification etc.) are known.

However, in the conventional composition, in a stepper exposure using a g-line of a mercury lamp currently used in the manufacture of semiconductor devices, the residual film ratio is greatly reduced due to the influence of long wavelength exposure and oxygen desensitization, and the desired film thickness is reduced. It was difficult to obtain a film, and the film was roughened during development.

In addition, since the highly sensitive photosensitive polyimide composition contains an azide compound or the like, a very small amount of a thermally decomposed product remains in the polyimide film during the heat treatment, and this makes the polyimide film dark brown. For this reason, when polyimide is used for an application such as a buffer coat, there is a disadvantage that a mark cannot be detected at the time of wiring bonding and alignment cannot be performed.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned drawbacks of the related art, and has an object of the above-mentioned drawbacks, that is, the film is reduced during g-line stepper exposure, the film is less rough, and It is an object of the present invention to provide an actinic ray-sensitive polymer composition having less coloring of a film after heat treatment.

[Means for Solving the Problems] The object of the present invention is to provide (1) (a) a general formula (1) (Where R ₁ is a trivalent or tetravalent organic group having at least 2 or more carbon atoms, R ₂ is a divalent organic group having at least 2 or more carbon atoms, R ₃ is hydrogen or alkali Represents a metal counter ion, wherein n is 1 or 2.
And (b) a compound [2] containing a dimerizable or polymerizable unsaturated bond and an amino group or a quaternary salt thereof by actinic radiation. (C) General formula (2) (R ₄ and R ₅ are those having at least 2 or more carbon atoms)
R ₆ represents a monovalent organic group having at least 3 or more carbon atoms. An actinic radiation-sensitive polymer composition comprising a coumarin compound [3] represented by the following formula: and (d) N-arylglycine [4].

Is achieved by

The polymer having the structural unit [1] in the present invention includes:
It has a structure represented by the general formula (1) and can be a polymer having an imide ring or other cyclic structure (hereinafter, referred to as a polyimide polymer) by heating or an appropriate catalyst.

In the structural unit [1], R ₁ is a trivalent or tetravalent organic group having at least two or more carbon atoms. From the viewpoint of the heat resistance of the polyimide polymer, R1 preferably has a structure in which the bond to the carbonyl group of the polymer main chain is made directly from the aromatic heterocycle. Therefore, R ₁ contains an aromatic ring or an aromatic heterocyclic ring and has 3 to 6 carbon atoms.
A valent or tetravalent group is preferred.

Preferred specific examples of R ₁ include: (In the formula, a bond represents a bond to a carbonyl group of a polymer main chain, and a carbonyl group of a polymer side chain is located at an ortho position with respect to the bond. The bond is described in the above structural formula. But not limited thereto).

In the polymer having the structural unit [1], R ₁ may be composed of only one of these, or may be a copolymer composed of two or more.

Particularly desirable as R ₁ are: (Wherein, the definition of a bond is the same as described above).

In the above structural unit [1], R ₂ is a divalent organic group having at least two or more carbon atoms. However, from the viewpoint of heat resistance when a polyimide-based polymer is used, R ₂ is an amide group in the polymer main chain. Those having a structure in which a bond is directly formed from an aromatic ring or an aromatic heterocycle are preferable. Therefore, R ₂ is preferably a divalent group containing an aromatic ring or an aromatic hetero ring and having 6 to 30 carbon atoms.

Preferred specific examples of R ₂ include: (Wherein the bond represents a bond to an amide group of the main chain). These may have a nuclear substituent such as an amino group, an azide group, a carboxyl group, or a sulfonamide group as long as they do not adversely affect the heat resistance of the polyimide polymer.

Particularly preferred examples of those having these core substituents include the following.

And the like.

In the polymer having the structural unit [1], R ₂ may be composed of only one of these, or may be a copolymer composed of two or more.

Further, in order to improve the adhesiveness of the polyimide-based polymer, it is also possible to copolymerize an aliphatic group having a siloxane bond as R ₂ as long as the heat resistance is not reduced. Preferred specific examples include: And the like.

Specific examples of the polymer having the structural unit [1] as a main component include pyromellitic dianhydride, 4,4'-diaminodiphenyl ether, and 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride And 4,4'-diaminodiphenyl ether, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether, pyromellitic dianhydride and 3,3'-(or 4 , 4 ') diaminodiphenylsulfone, 3,3', 4,4'-benzophenonetetracarboxylic dianhydride and 3,3 '-(or 4,4') diaminodiphenylsulfone, 3,3 ', 4,4 '-Biphenyltetracarboxylic dianhydride and 3,3'-(or 4,4 ') diaminodiphenyl sulfone, 3,3', 4,4'-benzophenonetetracarboxylic dianhydride and 4,4'-diamino Diphenyl sulfide, 3,3 ', 4,4'-biphenyltetracar Dianhydride and 4,4'-diaminodiphenyl sulfide; 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride and paraffin diamine; 3,3', 4,4'-biphenyltetracarboxylic Polyamic acids synthesized from acid dianhydride and paraphenylenediamine, 3,3 ', 4,4'-diphenylethertetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether, and the like are preferably used.

The polymer having the structural unit [1] refers to the structural unit [1]
Or a copolymer or blend with other structural units. It is desirable that the type and amount of the structural unit used for copolymerization be selected within a range that does not significantly impair the heat resistance of the polyimide polymer obtained by the final heat treatment.

Structural units of polyamide amide acid and polyester amide acid are typical examples, but are not limited thereto.

In the present invention, as the compound [2] containing an unsaturated bond capable of being dimerized or polymerized by actinic radiation and an amino group or a quaternized salt thereof, a carbon-carbon double bond and an amino group or a quaternized A compound containing an amino group is used.

As the compound [2], at least one compound represented by the following general formula [A], [B] or [C] or a quaternized salt thereof is preferably used.

(Where R ₇ is hydrogen or a phenyl group, R ₈ is hydrogen or a lower alkyl group having 1 to 6 carbon atoms, R ₁₀ is a substituted or unsubstituted carbon hydrogen group having 2 to 12 carbon atoms, R ₉ and R ₁₁ are Represents a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms).

General formula [B] (R ₁₂ represents a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms).

General formula [C] (Where R ₁₃ represents hydrogen or a methyl group, n +
1 = 3, n = 1 to 3).

Preferred specific examples include: And the like, but are not limited thereto.

From the viewpoint of actinic radiation sensitivity, an amino compound having an acryl group or a methacryl group as an unsaturated group is particularly desirable.

In the case of a compound in which the amino group is not quaternized, it is preferable to combine the compound with a compound in which R ₃ of the structural unit [1] is hydrogen. In the case of a compound in which the amino group is quaternized, it is desirable that R _{3 in the} structural unit [1] be combined with an alkali metal ion or an ammonium ion.

The compound [2] is preferably blended in an amount of 0.05 equivalent or more of all carboxyl groups (or a salt thereof) of the polymer having the structural unit [1] as a main component, more preferably 0.3 equivalent or more.
It is desirable that it be mixed with the polymer in an amount equivalent to twice or less. If the ratio is out of this range, the photosensitivity may be deteriorated, or the allowable range of the developing conditions such as the developing time and the temperature may be narrowed.

The coumarin compound [3] in the present invention has the general formula (2) (R ₄ and R ₅ are a monovalent organic group having at least 2 or more, preferably 10 or less carbon atoms, and R ₆ is a monovalent organic group having at least 3 or more, preferably 30 or less carbon atoms. Any substituent can be used in the skeleton as long as it is a compound having a coumarin skeleton represented by the formula (1) and having absorption at the g-line (436 nm) of a mercury lamp. However, from the viewpoint of workability, those having absorption up to the visible light region are not preferable. For example, the following coumarin compounds are preferable.

The coumarin compound [3] is desirably mixed in an amount of 0.1% by weight or more based on the weight of the polymer containing the structural unit [1] as a main component, more preferably 0.5% by weight or more based on the weight of the polymer, and 20% by weight. % Or less. If the ratio is out of this range, the sensitivity may deteriorate, and the allowable range of the developing time and the developing conditions may be reduced.

The N-arylglycine [4] in the present invention is a compound in which an aromatic ring is directly bonded to the nitrogen atom of glycine, and the aromatic ring referred to herein is a benzene ring, a naphthalene ring, an anthracene ring, a naphthoquinone ring. , Anthraquinone ring, etc., and these aromatic rings are lower (having 1 to 1 carbon atoms).
6) may be substituted with a substituent such as an alkyl group, an alkoxy group, a nitro group, a halogen group, a carboxyl group, a carboxyester group, a secondary or tertiary amino group, or a -O- group,- CO- group, -SO ₂ - group, -CH ₂ -
It may be unsubstituted or bonded to another aromatic ring substituted with the above substituent via a divalent group such as a group, -CH = CH-.

Specifically, N-arylglycine [4] such as N-phenylglycine and N-naphthylglycine is preferably used, but is not limited thereto.

The N-arylglycine [4] is preferably added at a ratio of 0.05% by weight or more and 10% or less based on the weight of the polymer containing the structural unit [1] as a main component. Care must be taken if the ratio is out of this range, as this may adversely affect the developability and the stability of the composition.

An example of the method for producing the composition of the present invention will be described.
First, a diamine compound and an acid dianhydride are reacted in a solvent,
A polymer having the structural unit [1] as a main component is obtained. Next, the compound [2], [3] and [4] and, if necessary, other additives can be dissolved and prepared in this solution.

As the above-mentioned polymer, a solid polyamic acid polymer or a polymer separated and purified from a solution after the reaction may be used after being dissolved again.

As the solvent used in the above production method, a polar solvent is preferably used from the viewpoint of the solubility of the polymer, and an aprotic polar solvent is particularly preferable. As the aprotic polar solvent, N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphorotriamide, γ-butyrolactone and the like are preferably used. As other additives, a sensitizer, a copolymerized monomer or an adhesion improver with a substrate may be contained as long as the sensitivity and heat resistance are not significantly reduced.

In addition, the compounding amount of the compound [3 [and / or [4]
In the case of 0.5 to 10% by weight, Michler's ketone, 4,4'-bis (diethylamino) benzophenone and the like are preferably used as sensitizers. Addition of a sensitizer can further enhance the actinic radiation sensitivity of the composition of the present invention. Monomaleimide, polymaleimide or a substituted product thereof is preferably used as the copolymerized monomer.

Next, a method for using the composition of the present invention will be described.
The composition of the present invention can be patterned by a known fine processing technique using actinic radiation.

First, the composition of the present invention is coated on a suitable support.
Examples of the application method include spin coating using a spinner, spray coating using a spray coater, dipping, printing, and roll coating. The coating thickness can be adjusted by the coating means, the solid content concentration of the composition, and the viscosity.

Examples of the material of the support on which the composition of the present invention is applied include metals, glass, semiconductors, metal oxide insulators, and silicon nitride.

In order to improve the adhesion between the coating film of the composition of the present invention or the polyimide film after the heat treatment and the support, an adhesion aid may be appropriately used.

Oxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ
Organic silicon compounds such as -aminopropyltriethoxysilane and γ-methacryloxypropyltrimethoxysilane; aluminum chelate compounds such as aluminum monoethylacetoacetate diisopropylate; aluminum tris (acetylacetonate); and titanium bis (acetylacetonate) ) And the like are preferably used.

Next, the composition of the present invention which has been formed into a coating film on the support is irradiated with actinic radiation in a desired pattern. X for actinic radiation
Examples thereof include rays, electron beams, ultraviolet rays, and visible rays, but ultraviolet rays and short-wavelength visible rays, that is, 200 to 500 nm in a wavelength range are preferred.

Next, a relief pattern is obtained by dissolving and removing the unirradiated portion with a developing solution. An appropriate developer is selected according to the structure of the polymer.

The developing solution contains N-methyl-2-pyrrolidone, N-acetyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphortriamide, etc., which are the solvents of the present composition. It can be used alone or as a mixture with a non-solvent of a composition such as methanol, ethanol, isopropyl alcohol, water, methyl carbitol, ethyl carbitol, toluene and xylene. In many cases, aqueous ammonia or other alkaline aqueous solutions can be used.

The development can be carried out by spraying the above-mentioned developer onto the coating film surface, immersing the developer in the developer, or applying ultrasonic waves while immersing the developer.

The relief pattern formed by development is desirably washed with a rinse solution. As the rinse solution, methanol, ethanol, isopropyl alcohol, butyl acetate, or the like having good miscibility with the developer is preferably used.

The polymer of the relief pattern obtained by the above treatment is a precursor of a polyimide-based polymer having heat resistance, and becomes a heat-resistant polymer having an imide ring or other cyclic structure by heat treatment. The heat treatment is usually performed in a temperature range of 135 to 400 ° C. while increasing the temperature stepwise or continuously.

The actinic radiation-sensitive polymer composition of the present invention can be used for passivation films of semiconductors, buffer coat films of passivation films, interlayer insulation films of multilayer integrated circuits, interlayer insulation films and surface protection films of hybrid integrated circuits, and soldering of printed circuits. Protective film,
It is used for forming an alignment film for liquid crystal and an interlayer insulating film of a mounting substrate. Further, it is also possible to apply a metal as a highly heat-resistant photoresist or a dry etching process. It can be applied to other known uses of polyimide.

[Effects of the Invention] As described above, the present invention provides a polymer containing a structural unit [1] as a main component and a compound containing an unsaturated bond capable of being dimerized or polymerized by actinic radiation and an amino group or a quaternized salt thereof [ 2], a coumarin compound [3], and an N-arylglycine [4]. The composition comprises an actinic radiation-sensitive composition. High sensitivity is obtained by g-line exposure of a high-pressure mercury lamp that cannot be seen, and a film with less coloring of the cured film is obtained.

[Examples] Next, the present invention will be specifically described based on Examples.
The present invention is not limited to these.

The evaluation of the actinic radiation sensitivity of the composition of the present invention was carried out by adding a gray scale (Kodak Ph.D.
The test was performed by irradiating light from a high-pressure mercury lamp through a filter (Y-43 made by Toshiba Glass) via an otographic step tablet No. 21 steps), and then developing the film to check the film roughness and film loss after development. .

Example 1 207.65 g of 4,4'-diaminodiphenyl sulfide, 1,3
Dissolving 9.94 g of -bis (3-aminopropyl) tetramethyldisiloxane in 1530 g of N-methyl-2-pyrrolidone;
The amine solution was prepared. To this amino solution was added 213.7 g of pyromellitic anhydride and reacted at 50 ° C for 3 hours.
A 130 poise polymer solution (A) was obtained. This polymer solution (A) is mixed with 370 g of diethylaminoethyl methacrylate, and 17.25 g of a coumarin compound (“Terrasil brilliant flavin” manufactured by Ciba Geigy) and 17.25 g of N-phenylglycine are dissolved in 250 g of N-methyl-2-pyrrolidone. The resulting solution was mixed and filtered.

The obtained solution is spin-coated on a silicon wafer with a spinner, and then dried at 90 ° C. and 95 ° C. for 3 minutes each using a vacuum adsorption type hot plate (SCW636 type manufactured by Dainippon Screen Co., Ltd.). Was. The thickness of this coating film was 10 μm. Next, the coating film was exposed to an exposure machine (PLA-5 manufactured by Canon Inc.).
01F), gray scale (Kodak Photogr
aphic step tablet No2 21 steps) and a filter (Y-43 made by Toshiba Glass) for 2 minutes. At this time, the intensity of the ultraviolet light was 5 mW / cm ² (436 nm). Development was carried out by immersion development using a mixed solvent of N-methylpyrrolidone (70 parts) and xylene (30 parts). The development was continued for an additional 30 seconds immediately after the unexposed portion was dissolved. Then, it was rinsed with isopropanol for 20 seconds and spin-dried with a spinner. When the film thickness after development was measured, it was 7.8 μm.
(Film loss: 2.2 μm) Thereafter, heat treatment was performed at 200 ° C. and 350 ° C. for 30 minutes, and the pattern was observed using an optical microscope. The pattern showed a good pattern without film roughness at an exposure dose of 200 mJ or more. .

After the heat treatment at 400 ° C., a brown coating film with very little coloring was obtained.

Example 2 192.2 g of 4,4'-diaminodiphenyl ether, 1,3-bis (3-aminopropyl) tetramethyldisiloxane 9.
94 g was dissolved in 1890 g of N-methyl-2-pyrrolidone to prepare an amine solution. To this amine solution, 315.7 g of benzophenonetetracarboxylic anhydride was added and reacted at 50 ° C. for 3 hours to obtain a polymer solution (B) of 150 poise at 25 ° C.
370 g of diethylaminoethyl methacrylate was mixed with the polymer solution (B), and then a coumarin compound ("Terasea Brilliant Flavin" manufactured by Ciba Geigy) 17.25
g and a solution of 17.25 g of N-phenylglycine dissolved in 250 g of N-methyl-2-pyrrolidone were mixed and filtered.

The obtained solution was spin-coated on a silicon wafer with a spinner, and then dried at 80 ° C. for 1 hour. The thickness of this coating film was 10 μm. Next, after this coating film was exposed under the same conditions as in Example 1, immersion development was performed using a mixed solvent of N-methylpyrrolidone (70 parts) and methanol (30 parts). The development time was 30 minutes immediately after the unexposed part was dissolved.
Development was continued for a second. Then, it was rinsed with isopropanol for 20 seconds and spin-dried with a spinner. When the film thickness after development was measured, it was 8.0 μm. (Film loss: 2.0 μm)
Thereafter, heat treatment was performed at 200 ° C. and 350 ° C. for 30 minutes, and the pattern was observed using an optical microscope. As a result, a good pattern without film roughness was obtained at an exposure dose of 150 mJ or more.

Thereafter, heat treatment was performed at 200 ° C. and 350 ° C. for 30 minutes each, and the pattern was observed using an optical microscope. The pattern showed a good pattern without exposure to light at an exposure dose of 200 mJ or more.

After the heat treatment at 400 ° C., a brown coating film with very little coloring was obtained.

Comparative Example 1 370 g of diethylaminoethyl methacrylate was mixed with the same polymer solution (A) as used in Example 1, then 10.3 g of N-phenyldiethanolamine and 20.6 g of 4-azidobenzalacetophenone were added to N-methyl-2-methyl-2-ethanol. A solution dissolved in 300 g of pyrrolidone was mixed and filtered.

The obtained solution is spin-coated on a silicon wafer with a spinner, and then dried at 90 ° C. and 95 ° C. for 3 minutes each using a vacuum adsorption type hot plate (SCW636 type manufactured by Dainippon Screen Co., Ltd.). Was. The thickness of this coating film was 10 μm. Next, this coating film was exposed under the same conditions as in Example 1,
Developed and dried. When the film thickness after development was measured, 5.4
μm (film loss: 4.6 μm). After this, 200 ℃, 3
Heat treatment was performed at 50 ° C. for 30 minutes, and the pattern was observed using an optical microscope. As a result, even at an exposure dose of 600 mJ, the film was rough.

After the heat treatment at 400 ° C., a large brown colored coating film was obtained.

Comparative Example 2 370 g of diethylaminoethyl methacrylate was mixed with the same polymer solution (B) as used in Example 2, then a solution of 20.6 g of Michler's ketone dissolved in 250 g of N-methyl-2-pyrrolidone was mixed and filtered. .

The obtained solution was spin-coated on a silicon wafer with a spinner, and then dried at 80 ° C. for 1 hour. The thickness of this coating film was 10 μm. Next, when this coating film was subjected to exposure and immersion development under the same conditions as in Example 2, the image was dissolved even at an exposure dose of 720 mJ (film loss: 10.0 μm).
m).

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03F 7/037 G03F 7/028 C08L 79/08

Claims (1)

(57) [Claims] (1) General formula (1) (Where R ₁ is a trivalent or tetravalent organic group having at least 2 or more carbon atoms, R ₂ is a divalent organic group having at least 2 or more carbon atoms, R ₃ is hydrogen or alkali A polymer having a structural unit [1] as a main component represented by the following formula: (b) a dimerized or polymerizable unsaturated bond by actinic radiation, and A compound [2] containing an amino group or a quaternary salt thereof, and (c) a general formula (2) (R ₄ and R ₅ are those having at least 2 or more carbon atoms)
R ₆ represents a monovalent organic group having at least 3 or more carbon atoms. And (d) N-arylglycine [4]. An actinic radiation-sensitive polymer composition comprising: