JP4789657B2 - Photosensitive resin composition - Google Patents

Description

  The present invention relates to a photosensitive resin composition used for forming relief patterns such as a passivation film, a buffer coat film, and an interlayer insulating film in a semiconductor device.

  Conventionally, polyimide resins having excellent heat resistance, electrical characteristics, and mechanical characteristics have been used for insulating materials for electronic components, passivation films, surface protective films, interlayer insulating films, and the like for semiconductor devices. Among these polyimide resins, in the case of those provided in the form of a photosensitive polyimide precursor composition, this is applied to a substrate, exposed, developed, and subjected to a thermal imidization treatment, etc. to provide a heat resistant relief. A pattern film can be easily formed. Such a photosensitive polyimide precursor composition has a feature that the process can be greatly shortened as compared with the case of using a conventional non-photosensitive polyimide.

  When using said photosensitive polyimide precursor composition, generally the process of curing at the temperature of 300 degreeC thru | or more is required. However, in recent years, there have been cases where curing at such temperatures is not appropriate. For example, there is a semiconductor device using a magnetoresistive element described in Non-Patent Document 1. Many of the magnetic materials used in such semiconductor devices are thermally diffused at a temperature of about 300 ° C., which may impair the original performance as a magnetoresistive element. Therefore, a temperature of 300 ° C. or higher cannot be applied in the semiconductor device manufacturing process after the magnetic material is formed. Similar demands arise not only for semiconductor devices, but also when applying polyimide resin to various thermally limited devices such as image sensors equipped with optical lenses and display elements using organic electroluminescence. obtain.

  When the polyimide resin is used at a reduced curing temperature, there are two major problems. The first problem is that the imidization reaction does not proceed sufficiently, so that the resulting resin film cannot fully exhibit the original performance of the polyimide resin such as heat resistance and chemical resistance. Second, even if the imidization reaction proceeds sufficiently, a large amount of volatile components remain in the resin film to be produced, and this volatilizes during the manufacturing process of the semiconductor device and the like and adversely affects its performance. It is a problem that there is a risk of affecting.

  Several methods for solving the first problem by using an additive or the like have been proposed. For example, Patent Document 1 discloses that a resin obtained from a composition containing a polyimide precursor and a compound having a triazine skeleton or a vinyl group can improve other physical properties while maintaining heat resistance. Yes. Alternatively, Patent Document 2 discloses that a polyimide resin composition having an isocyanurate ring exhibits a good glass transition temperature. However, there is currently no known solution for the second problem.

JP 2002-12761 A JP 2003-221429 A Ando, “Universal Memory MRAM”, Applied Physics, Japan Society of Applied Physics, March 2004, “Applied Physics” Vol. 73, No. 3, 390-393

  This invention is providing the photosensitive resin composition which can form the resin film which does not generate | occur | produce a 2nd problem mentioned above, ie, a volatile component, even if it cures at low temperature, for example, 200 degreeC conventionally.

As a result of intensive studies, the present inventors have found that the above problems can be solved by a composition containing a specific polyamide and an isocyanuric acid derivative having a photopolymerizable unsaturated bond, and have reached the present invention.
That is, the first of the present invention is a photosensitive resin composition comprising, as essential components, a polyamide, an isocyanuric acid derivative having a photopolymerizable unsaturated bond, and a photopolymerization initiator .
(A) The polyamide is a polyamide having a structural unit represented by the following formula (1),
(B) The isocyanuric acid derivative having a photopolymerizable unsaturated bond is an ethylene oxide-modified or propylene oxide-modified isocyanuric acid derivative represented by the following formula (3), and (A) of (B) with respect to 100 parts by mass: Ri content 15-70 parts by der a photosensitive resin composition characterized that you contain (C) a photopolymerization initiator.

〔式中、Ｘは４価の芳香族基であって、−ＣＯＯＲ¹基および−ＣＯＯＲ²基と−ＣＯＮＨ−基とは互いにオルト位置にある。Ｙは２価の芳香族基であり、ｍは２〜１５０の整数である。Ｒ¹とＲ²のうち１つは下記式（２）で表される光重合性の不飽和二重結合を有する一価の有機基であり、他の１つは下記式（２）で表される光重合性の不飽和二重結合を有する一価の有機基であるか、水素原子または炭素数１〜４の一価の飽和脂肪族基である。

[Wherein, X is a tetravalent aromatic group, and the —COOR ¹ group, the —COOR ² group, and the —CONH— group are in the ortho positions to each other. Y is a divalent aromatic group, and m is an integer of 2 to 150. One of R ¹ and R ² is a monovalent organic group having a photopolymerizable unsaturated double bond represented by the following formula (2), and the other is represented by the following formula (2). It is a monovalent organic group having a photopolymerizable unsaturated double bond, or a hydrogen atom or a monovalent saturated aliphatic group having 1 to 4 carbon atoms.

（式中、Ｒ³は水素原子または炭素数１〜３の一価の有機基であり、Ｒ⁴、およびＲ⁵は、それぞれ独立に、水素原子または炭素数１〜３の一価の有機基であり、Ｒ⁶は直鎖または分岐を有していてもよい２価の有機基である。）〕

(Wherein R ³ is a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and R ⁴ and R ⁵ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms. And R ⁶ is a divalent organic group which may be linear or branched.)]

［式中、Ｒ⁷はそれぞれ独立に、式（４）で表される一価の置換基である。

[Wherein R ⁷ is each independently a monovalent substituent represented by the formula (4).

〔式中、Ｒ⁸はエチレン基またはプロピレン基、Ｒ⁹は式（５）で表される一価の置換基であり、ｎは１から４までの整数、ｐは４から６までの整数である。ｑは０から３までの整数であるが、すべてのＲ⁷について同時に０であることはない。

[Wherein R ⁸ is an ethylene group or propylene group, R ⁹ is a monovalent substituent represented by the formula (5), n is an integer from 1 to 4, and p is an integer from 4 to 6. is there. q is an integer from 0 to 3, but is not 0 simultaneously for all R ⁷ .

（式中、Ｒ¹⁰は水素原子又はメチル基を表す。）〕］

(Wherein R ¹⁰ represents a hydrogen atom or a methyl group)]]]

In the second aspect of the present invention, (1) a step of applying a photosensitive resin composition of the present invention to a substrate to form a coating film, and (2) the resulting coating film is activated through a patterning mask. A step of irradiating light to form an exposed portion, (3) a step of dissolving and removing the unexposed portion of the coating film using a developer to form a relief pattern comprising the exposed portion, and (4) 140 to 450 ° C. A method for forming a cured relief pattern, comprising the step of heating the relief pattern at a temperature of
A third aspect of the present invention is a method for manufacturing a semiconductor device including the second cured relief pattern forming method of the present invention.

  According to the photosensitive resin composition of the present invention, a resin film with less volatile components can be obtained even when the curing temperature of a polyimide resin conventionally requiring 300 ° C. or higher is performed at 200 ° C.

The present invention will be specifically described below.
The photosensitive resin composition of the present invention is also called polyamide (hereinafter also referred to as “component A”) and an isocyanuric acid derivative having a photopolymerizable unsaturated bond (hereinafter also referred to as “component B”) as essential components. )including.
<A component>
Among these, the A component will be described first.
Component A in the photosensitive resin composition of the present invention is a polyamide having a structural unit represented by the following chemical formula (1).

〔式中、Ｘは４価の芳香族基であって、−ＣＯＯＲ¹基および−ＣＯＯＲ²基と−ＣＯＮＨ−基とは互いにオルト位置にある。Ｙは２価の芳香族基であり、ｐは２〜１５０の整数である。Ｒ¹とＲ²のうち1つは下記式（２）で表される光重合性の不飽和二重結合を有する一価の有機基であり、他の１つは下記式（２）で表される光重合性の不飽和二重結合を有する一価の有機基であるか、水素原子または炭素数１〜４の一価の飽和脂肪族基である。

[Wherein, X is a tetravalent aromatic group, and the —COOR ¹ group, the —COOR ² group, and the —CONH— group are in the ortho positions to each other. Y is a divalent aromatic group, and p is an integer of 2 to 150. One of R ¹ and R ² is a monovalent organic group having a photopolymerizable unsaturated double bond represented by the following formula (2), and the other is represented by the following formula (2). It is a monovalent organic group having a photopolymerizable unsaturated double bond, or a hydrogen atom or a monovalent saturated aliphatic group having 1 to 4 carbon atoms.

（式中、Ｒ³は水素原子または炭素数１〜３の一価の有機基であり、Ｒ⁴、およびＲ⁵は、それぞれ独立に、水素原子または炭素数１〜３の一価の有機基であり、Ｒ⁶は直鎖または分岐を有していてもよい２価の有機基である。）〕

(Wherein R ³ is a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and R ⁴ and R ⁵ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms. And R ⁶ is a divalent organic group which may be linear or branched.)]

  A polyamide having a structural unit represented by the chemical formula (1) (hereinafter, also referred to as “polyimide precursor”) includes, for example, an aromatic tetracarboxylic dianhydride containing a tetravalent aromatic group X, and photopolymerization. A half-acid / half-reaction by reacting an alcohol having a polymerizable unsaturated double bond or a mixture of an alcohol having a photopolymerizable unsaturated double bond with a saturated aliphatic alcohol having 1 to 4 carbon atoms After preparing an ester body, it is obtained by carrying out amide polycondensation between this and an aromatic diamine containing a divalent aromatic group Y.

(Preparation of half acid / half ester body)
Examples of the tetracarboxylic dianhydride containing a tetravalent aromatic group X preferably used in the present invention include pyromellitic anhydride and diphenyl ether-3,3 ′, 4,4′-tetracarboxylic dianhydride. , Benzophenone-3,3 ′, 4,4′-tetracarboxylic dianhydride, biphenyl-3,3 ′, 4,4′-tetracarboxylic dianhydride, diphenylsulfone-3,3 ′, 4,4 '-Tetracarboxylic dianhydride, diphenylmethane-3,3', 4,4'-tetracarboxylic dianhydride, 2,2-bis (3,4-phthalic anhydride) propane, 2,2-bis ( 3,4-phthalic anhydride) -1,1,1,3,3,3-hexafluoropropane and the like may be mentioned, but the invention is not limited to these. These can be used alone or in combination of two or more.

Examples of alcohols having a photopolymerizable unsaturated double bond that can be suitably used in the present invention include 2-acryloyloxyethyl alcohol, 1-acryloyloxy-3-propyl alcohol, 2-acrylamidoethyl alcohol, and methylol. Vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-t-butoxypropyl acrylate, 2-hydroxy-3-cyclohexyloxypropyl acrylate, 2-methacryloyloxyethyl alcohol, 1-methacryloyloxy-3-propiyl Alcohol, 2-methacrylamidoethyl alcohol, methylol vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-phenoxypropyl methacrylate, Examples include 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-t-butoxypropyl methacrylate, and 2-hydroxy-3-cyclohexyloxypropyl methacrylate.

The alcohol having a photopolymerizable unsaturated double bond partially includes a saturated aliphatic alcohol having 1 to 4 carbon atoms such as methanol, ethanol, n-propanol, isopropanol, n-butanol, tert-butanol and the like. They can also be used in combination (hereinafter, both are simply referred to as “alcohols”). The amount in the case of mixing a saturated aliphatic alcohol having 1 to 4 carbon atoms is preferably 0 to 50 mol% of the total alcohols.
By stirring and dissolving the aromatic tetracarboxylic dianhydride suitable for the present invention and alcohols in an appropriate solvent in the presence of a basic catalyst such as pyridine, the tetracarboxylic dianhydride is mixed. The esterification reaction proceeds, and a desired half acid / half ester body can be obtained.

As the reaction solvent, a half acid / half ester body and a polyimide precursor which is an amide polycondensation product of this with a diamine component are preferably dissolved. For example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, tetramethylurea, gamma butyrolactone (hereinafter also referred to as “GBL”) and the like.
In addition, as ketones, esters, lactones, ethers, halogenated hydrocarbons, hydrocarbons, for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, oxalic acid Examples include diethyl, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, chlorobenzene, o-dichlorobenzene, hexane, heptane, benzene, toluene, xylene and the like. These reaction solvents can be used alone or in combination as required.

(Preparation of polyimide precursor)
To the half acid / half ester solution obtained by the above method, an appropriate dehydration condensation agent such as dicyclohexylcarbodiimide, 1-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline, 1,1 is added under ice cooling. '-Carbonyldioxy-di-1,2,3-benzotriazole, N, N'-disuccinimidyl carbonate and the like are charged and mixed to form a half acid / half ester body as a polyanhydride. The target polyimide precursor can be obtained by dropping diamines containing a divalent aromatic group Y preferably used in the above, separately dissolved or dispersed in a solvent, and subjecting the amide to polycondensation. I can do it.

Examples of diamines containing a divalent aromatic group Y that are suitably used in the present invention include p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 4,4′-diaminodiphenyl sulfide, 3,4′-diaminodiphenyl sulfide, 3,3′-diaminodiphenyl sulfide, 4,4′-diaminodiphenyl sulfone, 3,4′-diamino Diphenylsulfone, 3,3′-diaminodiphenylsulfone, 4,4′-diaminobiphenyl, 3,4′-diaminobiphenyl, 3,3′-diaminobiphenyl, 4,4′-diaminobenzophenone, 3,4′-diamino Benzophenone, 3,3 '
-Diaminobenzophenone, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-amino) Phenoxy) benzene,

1,3-bis (3-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 4,4-bis (4-amino) Phenoxy) biphenyl, 4,4-bis (3-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy) phenyl] ether, 1,4-bis (4-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 9,10-bis (4-aminophenyl) anthracene, 2,2-bis (4-aminophenyl) propane, 2,2 -Bis (4-aminophenyl) hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2 Bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 1,4-bis (3-aminopropyl dimethylsilyl) benzene,
Ortho-tolidine sulfone and 9,9-bis (4-aminophenyl) fluorene, and some of the hydrogen atoms on these benzene rings are methyl, ethyl, hydroxymethyl, hydroxyethyl, and halogen atoms Substituted with any group selected from the group consisting of 3,3′-dimethyl-4,4′-diaminobiphenyl, 2,2′-dimethyl-4,4′-diaminobiphenyl, 3,3 '-Dimethyl-4,4'-diaminodiphenylmethane, 2,2'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dichloro-4 , 4′-diaminobiphenyl, and mixtures thereof, but are not limited thereto.
In addition, diaminosiloxanes such as 1,3-bis (3-aminopropyl) tetramethyldisiloxane and 1,3-bis (3-aminopropyl) tetraphenyldisiloxane for the purpose of improving adhesion to various substrates. Can also be copolymerized.

After completion of the reaction, the water-absorbing by-product of the dehydrating condensing agent coexisting in the reaction solution is filtered off if necessary, and then the obtained polyamide such as water or an aliphatic lower alcohol or a mixture thereof is used. A poor solvent is added, polyamide is precipitated, and further purified by repeating redissolution and reprecipitation, and vacuum drying is performed to isolate the target polyimide precursor.
In order to further improve the degree of purification, the polymer solution may be passed through a column packed with an anion-cation exchange resin swollen with an appropriate organic solvent to remove ionic impurities.

<B component>
Next, the B component which is an isocyanuric acid derivative having a photopolymerizable unsaturated bond will be described.
The isocyanuric acid derivative having a photopolymerizable unsaturated bond used as the component (B) of the photosensitive resin composition of the present invention is an ethylene oxide-modified or propylene oxide-modified isocyanuric acid derivative represented by the formula (3).

［式中、Ｒ⁷はそれぞれ独立に、式（４）で表される一価の置換基である。

[Wherein R ⁷ is each independently a monovalent substituent represented by the formula (4).

〔式中、Ｒ⁸はエチレン基またはプロピレン基、Ｒ⁹は式（５）で表される一価の置換基であり、ｎは１から４までの整数、ｐは４から６までの整数である。ｑは０から３までの整数であるが、すべてのＲ⁷について同時に０であることはない。

[Wherein R ⁸ is an ethylene group or propylene group, R ⁹ is a monovalent substituent represented by the formula (5), n is an integer from 1 to 4, and p is an integer from 4 to 6. is there. q is an integer from 0 to 3, but is not 0 simultaneously for all R ⁷ .

（式中、Ｒ¹⁰は水素原子又はメチル基を表す。）〕］

(Wherein R ¹⁰ represents a hydrogen atom or a methyl group)]]]

In the formula (3), there are three substituents R ⁷ each independently represented by the formula (4). To achieve the object of the present invention, at least one of these three is a valerolactone-modified group, The substituent needs to have any modification group selected from the group consisting of a caprolactone modification group and an enanthlactone modification group. That is, at least one of R ⁷ takes an integer value from 1 to 3 in q in equation (4). In view of compatibility with the component A already described, it is particularly preferable that all three R ⁷ are substituents having the modifying group. In the formula (4), R ⁸ is an ethylene group or a propylene group, and an ethylene group is particularly preferable. Further, the value of p may be an integer from 4 to 6, but the case of a caprolactone-modified group with p = 5 is particularly preferably used.

If the above conditions are satisfied, even if each substituent R ⁷ represented by formula (4) has a single value of n, p, and q, different values of n, p, and q May be used. As commercially available B component, for example, manufactured by Toagosei Co., Ltd .: M-325 (corresponding to the number q of caprolactone-modified groups is 1) and M-327 (also corresponding to 3) Can be used.
In order to achieve the object of the present invention while ensuring compatibility with the A component, the addition amount of the B component with respect to 100 parts by mass of the A component is preferably 15 parts by mass or more and 70 parts by mass or less. More preferably, it is 55 parts by mass or less. If it is in this range, the addition amount of the B component can be arbitrarily selected, but it is preferable that the addition amount of the B component is 40 parts by mass or more particularly when a film having a film thickness of 20 microns or more is required. .

<Other ingredients>
You may add a photoinitiator to the photosensitive resin composition of this invention as needed. Photopolymerization initiators that can be suitably used include: (a) benzophenone, methyl o-benzoylbenzoate, 4-benzoyl-4′-methyldiphenylketone, dibenzylketone, benzophenone derivatives such as fluorenone,
(B) Acetophenone derivatives such as 2,2′-diethoxyacetophenone, 2-hydroxy-2-methylpropiophenone, 1-hydroxycyclohexyl phenyl ketone,
(C) Thioxanthone derivatives such as thioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, diethylthioxanthone,

(D) benzyl derivatives such as benzyl, benzyldimethyl ketal, benzyl-β-methoxyethyl acetal,
(E) benzoin derivatives such as benzoin and benzoin methyl ether;
(F) 1-phenyl-1,2-butanedione-2- (o-methoxycarbonyl) oxime, 1-phenyl-1,2-propanedione-2- (o-methoxycarbonyl) oxime, 1-phenyl-1, 2-propanedione-2- (o-ethoxycarbonyl) oxime, 1-phenyl-1,2-propanedione-2- (o-benzoyl) oxime, 1,3-diphenylpropanetrione-2- (o-ethoxycarbonyl) ) Oximes, oximes such as 1-phenyl-3-ethoxypropanetrione-2- (o-benzoyl) oxime,
However, it is not limited to these. Moreover, in using these, it may be individual or a mixture of 2 or more types.

  Among the above photopolymerization initiators, the oxime (f) is more preferable particularly from the viewpoint of photosensitivity. The addition amount is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the component A. This is because, when the amount added is less than 1 part by mass, radicals sufficient for photoradical polymerization to proceed sufficiently are not supplied at the time of exposure, so the photosensitivity is low, and thus the pattern after development is severely swollen and practical. This is because it is difficult to obtain a relief pattern. On the contrary, if the addition amount exceeds 20 parts by mass, the exposure light beam near the surface of the coating film is excessively absorbed, so that the exposure light beam reaches near the substrate surface. This is because photocrosslinking is not uniform in the film thickness direction, and it is difficult to obtain a practical relief pattern.

  You may add the compound which has a photopolymerizable unsaturated double bond other than B component to the photosensitive resin composition of this invention as needed. As such a compound, a (meth) acrylic compound that can be polymerized by a photopolymerization initiator is preferable. For example, polyethylene glycol diacrylate (numbers 2 to 20 of each ethylene glycol unit), polyethylene glycol dimethacrylate (of each ethylene glycol unit). 2-20), poly (1,2-propylene glycol) diacrylate, poly (1,2-propylene glycol) dimethacrylate, pentaerythritol diacrylate, pentaerythritol dimethacrylate, glycerol diacrylate, glycerol dimethacrylate, dipenta Erythritol hexaacrylate, methylenebisacrylamide, N-methylolacrylamide, ethylene glycol diglycidyl ether-methacrylic acid adduct, glycero Examples include rubidiglycidyl ether-acrylic acid adduct, bisphenol A diglycidyl ether-acrylic acid adduct, bisphenol A diglycidyl ether-methacrylic acid adduct, N, N′-bis (2-methacryloyloxyethyl) urea, and the like. However, it is not limited to these. Moreover, in using these, you may use individually or in mixture of 2 or more types as needed. The addition amount is preferably 1 to 50 parts by mass with respect to 100 parts by mass of component A.

  A sensitizer for improving photosensitivity can be added to the photosensitive resin composition of the present invention as desired. Examples of such a sensitizer include Michler's ketone, 4,4′-bis (diethylamino) benzophenone, 2,5-bis (4′-diethylaminobenzylidene) cyclopentanone, and 2,6-bis (4′-diethylamino). Benzylidene) cyclohexanone, 2,6-bis (4′-dimethylaminobenzylidene) -4-methylcyclohexanone, 2,6-bis (4′-diethylaminobenzylidene) -4-methylcyclohexanone, 4,4′-bis (dimethylamino) ) Chalcone, 4,4′-bis (diethylamino) chalcone, 2- (4′-dimethylaminocinnamylidene) indanone, 2- (4′-dimethylaminobenzylidene) indanone, 2- (p-4′-dimethylamino) Biphenyl) benzothiazole, 1,3-bis (4-dimethyla) Nobenjiriden) acetone, 1,3-bis (4-diethylamino benzylidene) acetone, 3,3'-carbonyl - bis (7-diethylamino coumarin), 3-acetyl-7-dimethylamino coumarin,

3-ethoxycarbonyl-7-dimethylaminocoumarin, 3-benzyloxycarbonyl-7-dimethylaminocoumarin, 3-methoxycarbonyl-7-diethylaminocoumarin, 3-ethoxycarbonyl-7-diethylaminocoumarin, N-phenyl-N-ethyl Ethanolamine, N-phenyldiethanolamine, Np-tolyldiethanolamine, N-phenylethanolamine, 4-morpholinobenzophenone, isoamyl 4-dimethylaminobenzoate, isoamyl 4-diethylaminobenzoate, 2-mercaptobenzimidazole, 1-phenyl -5-mercapto-1,2,3,4-tetrazole, 1-cyclohexyl-5-mercapto-1,2,3,4-tetrazole, 1- (tert-butyl) -5-mercapto-1,2,3 , 4 -Tetrazole, 2-mercaptobenzothiazole, 2- (p-dimethylaminostyryl) benzoxazole, 2- (p-dimethylaminostyryl) benzthiazole, 2- (p-dimethylaminostyryl) naphtho (1,2-p) Examples include, but are not limited to, thiazole and 2- (p-dimethylaminobenzoyl) styrene. In use, it may be used alone or as a mixture of two or more. The amount added is preferably 0 to 15 parts by mass with respect to 100 parts by mass of component A, although there is a balance with the amount of other additive components.

  The photosensitive resin composition of the present invention is also suitably used to form a film thickness of about 40 microns, but when a thinner resin film is required, a solvent is used to reduce the viscosity of the composition. It may be used. Examples of such solvents include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, Examples thereof include, but are not limited to, tetramethylurea, dimethyl sulfoxide, hexamethylphosphoramide, pyridine, gamma butyrolactone, diethylene glycol monomethyl ether, and diethylene glycol dimethyl ether. In use, it may be used alone or as a mixture of two or more. The addition amount is preferably 50 to 500 parts by mass, more preferably 100 to 300 parts by mass with respect to 100 parts by mass of the component A.

If desired, a polymerization inhibitor can be added to the photosensitive resin composition of the present invention in order to improve the viscosity of the composition solution during storage and the stability of photosensitivity. Examples of such polymerization inhibitors include hydroquinone, N-nitrosodiphenylamine, p-tert-butylcatechol, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol etherdiaminetetraacetic acid. 2,6-di-tert-butyl-p-methylphenol, 5-nitroso-8-hydroxyquinoline, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, 2-nitroso-5- (N- Ethyl-N-sulfopropylamino) phenol, N-nitroso-N-phenylhydroxyamine ammonium salt, N-nitroso-N-phenylhydroxylamine ammonium salt,
N-nitroso-N- (1-naphthyl) hydroxylamine ammonium salt, bis (4-hydroxy-3,5-tert-butyl) phenylmethane and the like can be used, but are not limited thereto. It is preferable that the addition amount is 0-5 mass parts with respect to 100 mass parts of A component. This is because if the addition amount exceeds 5 parts by mass, there is a concern that the photocrosslinking reaction that should be originally expected is inhibited and the photosensitivity is lowered.
In addition to the above, the photosensitive resin composition of the present invention includes various characteristics of the photosensitive resin composition of the present invention, including a scattered light absorber, a coating film smoothness imparting agent, a silane coupling agent, and the like. As long as it does not inhibit, various additives can be blended as needed.

<Curing Relief Pattern Forming Method and Semiconductor Device Manufacturing Method>
The example of the method of forming a hardening relief pattern using the photosensitive resin composition of this invention is shown below.
First, the composition is applied to a substrate to form a coating film. Examples of the substrate include a silicon wafer, a ceramic, and an aluminum substrate. As a coating method, a spin coater, a spray coater, dipping, printing, a blade coater, roll coating or the like can be used. The substrate on which the coating film has been formed is prebaked at 80 to 120 ° C. to dry the coating film.

Next, the obtained coating film is irradiated with actinic rays through a patterning mask to form an exposed portion. The patterning mask in the present invention refers to a photomask in which a negative pattern is formed so that a portion to be dissolved and removed by development has a light-shielding property and a portion to be left after development has a light-transmitting property. Note that the patterning mask here includes a patterned reticle having the same function as the patterning mask. As the actinic ray, X-rays, electron beams, ultraviolet rays, visible rays and the like can be used. However, in the present invention, those having a wavelength of 200 to 500 nm are preferably used, particularly in terms of pattern resolution and handleability. UV-i radiation (365 nm) is preferred. Examples of the exposure projection apparatus include a contact aligner, a mirror projection, a stepper, etc. Among them, a stepper is preferable.
Thereafter, for the purpose of improving photosensitivity, the coating film may be subjected to post-exposure baking (PEB) or pre-development baking as necessary. As the baking conditions, for example, a temperature of 40 ° C. to 120 ° C. and a time of 10 seconds to 240 seconds are preferable.

Next, the unexposed portion of the coating film is dissolved and removed using a developer to form a relief pattern composed of the exposed portion. The developing method can be selected from methods such as an immersion method, a paddle method, and a rotary spray method. As the developer, a good solvent for the polyimide precursor can be used alone, or a good solvent and a poor solvent can be appropriately mixed. Good solvents include N-methyl-2-pyrrolidone, N-acetyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, gamma butyrolactone, α-acetyl-gammabutyrolactone, cyclopenta Non, cyclohexanone, etc. are used as the poor solvent, and toluene, xylene, methanol, ethanol, isopropanol, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, water and the like are used. When a good solvent and a poor solvent are mixed and used, the mixing ratio is adjusted according to the solubility of the photosensitive resin composition coating film used and the developing method used.
After the development, the substrate is washed with a rinse solution to remove the developer remaining on the surface of the relief pattern. As the rinsing liquid, distilled water, methanol, ethanol, isopropanol, toluene, xylene, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, or the like can be used alone or in combination as appropriate, or can be used in a stepwise combination.

Next, this relief pattern is heated at a temperature of 140 to 400 ° C. Although the reaction rate varies depending on the heating temperature and time, by proceeding with the dehydration cyclization reaction, the relief pattern made of polyamide is converted into a cured relief pattern in which a part or all of it is polyimideized. When this dehydration cyclization reaction is performed at a temperature of 200 ° C. or lower, a known curing accelerator may be added to accelerate the progress of the reaction. Such heating can be performed using a hot plate, an inert oven, a temperature rising oven that can set a temperature program, and the like. Air may be used as the atmospheric gas for heating, and an inert gas such as nitrogen or argon may be used.

  The cured relief pattern prepared by the above-described cured relief pattern forming method is known as a surface protective film, an interlayer insulating film, a rewiring insulating film, a protective film for a flip chip device, or a protective film for a device having a bump structure. A semiconductor device can be manufactured by combining with a method for manufacturing a semiconductor device. It is particularly suitable for the manufacture of semiconductor devices that are vulnerable to heat, such as MRAM. When applied to the manufacture of MRAM, after forming all of the magnetoresistive elements and the wirings that electrically couple them by a known method, the protection in which the conduction holes to the wirings are formed by the above-described cured relief pattern forming method A film can be formed and mounted. The photosensitive resin composition of the present invention can also form a thick film of about 40 microns by adjusting the concentration of the solvent, and the above-described cured relief pattern forming method can be applied thereto. According to this method, since the wiring insulating film of the semiconductor device can be thickened, the parasitic capacitance between the wiring layers can be reduced. At the same time, since the film thickness of the wiring itself can be increased, it can be suitably used to solve various problems caused by the resistance of the wiring, for example, the occurrence of electromigration and heat generation due to an increase in current density.

  The above-described cured relief pattern forming method is useful for applications other than the manufacture of semiconductor devices, for example, interlayer insulation of multilayer circuits, cover coating of flexible copper-clad plates, solder resist films, liquid crystal alignment films, etc. It is suitable for weak applications, for example, the production of microlens partition walls constituting an image sensor. In the case of this example, after forming a control circuit of the image sensor by a known CMOS process or CCD process, a microlens is formed, and the above-described cured relief pattern forming method is directly or via a necessary optical thin film. To form a partition for a microlens. Thereafter, if necessary, a glass plate or the like for sealing the image sensor can be formed on the partition wall with an adhesive.

Hereinafter, examples of embodiments of the present invention will be described in detail by way of examples.
(Synthesis of photosensitive polyimide precursor PSP-4)
In a separable flask having a volume of 5 l, 310.22 g (1.00 mol) of diphenyl ether-3,3 ′, 4,4′-tetracarboxylic dianhydride, 270.69 g (2.08 mol) of 2-methacryloyloxyethyl alcohol, 158.2 g (2.00 mol) of pyridine and 1000 g of GBL were added and mixed, and the mixture was left stirring at room temperature for 16 hours. A solution obtained by dissolving and diluting 400.28 g (1.94 mol) of dicyclohexylcarbodiimide in 400 g of GBL was added dropwise thereto over about 30 minutes under ice-cooling, followed by 185.97 g of 4,4′-diaminodiphenyl ether (0. 93 mol) dispersed in 650 g of GBL was added over about 60 minutes. The mixture was stirred for 3 hours while being ice-cooled, and then 50 g of ethanol was added, the ice-cooled bath was removed, and the mixture was further stirred for 1 hour. After filtering off the solid content precipitated in the above process, the reaction solution is dropped into 40 l of ethanol, and the polymer precipitated at that time is separated, washed, and vacuum dried at 50 ° C. for 24 hours, A photosensitive polyimide precursor PSP-4 was obtained. The polystyrene-equivalent GPC weight average molecular weight (THF solvent) was 22,000.

(Preparation of photosensitive resin composition)
<Example 1>
100 parts by mass of photosensitive polyimide precursor (PSP-4), 4 parts by mass of tetraethylene glycol dimethacrylate, 4.7 parts by mass of 1,3-diphenylpropanetrione-2- (o-ethoxycarbonyl) oxime, 1-phenyl -5-mercapto-1,2,3,4-tetrazole 1.2 parts by mass, N, N-bis (2-hydroxyethyl) aniline 4.7 parts by mass, N-nitrosodiphenylamine 0.05 parts by mass, It was dissolved in 165 parts by mass of N-methyl-2-pyrrolidone (NMP).
To this was added 15 parts by mass of caprolactone 3 mol modified product of isocyanuric acid ethylene oxide modified triacrylate (manufactured by Toagosei Co., Ltd., hereinafter abbreviated as “M-327”), and dissolved to be varnished. A photosensitive resin composition was obtained.

<Examples 2-3 and Comparative Examples 1-2>
In Example 1, the amount of M-327 added was set to 27.5 parts by mass and 55 parts by mass, respectively, to be Example 2 and Example 3, respectively. Moreover, the thing which did not add M-327 at all and the thing which added 5 mass parts were made into the comparative example 1 and the comparative example 2, respectively.
<Example 4>
A varnish-like photosensitive resin composition was prepared under the same conditions as in Example 1 except that the amount of NMP used to dissolve PSP-4 was 130 parts by mass.

(Preparation of polyamide coating)
The varnish-like compositions obtained in Examples 1 to 3 and Comparative Examples 1 and 2 of the present invention were applied to a spin coater (Tokyo Electron) on a 5-inch silicon wafer in which an aluminum thin film was previously formed by sputtering. The film was coated using a manufactured product type name Clean Track Mark 7) and prebaked at 95 ° C. for 3 minutes to obtain a coating film having a thickness of about 8 microns.
(Creation of film sample made of resin film)
After applying and prebaking each varnish of the example of the present invention and the comparative example on a 5-inch silicon wafer with an aluminum thin film by the above-mentioned method, using a vertical curing furnace (manufactured by Koyo Lindberg, model name VF-2000B). Then, a heat curing treatment was performed at 200 ° C. for 2 hours under a nitrogen atmosphere, and a resin film having a film thickness of 7 μm was prepared after curing. This resin film is cut into a width of 3.0 mm using a dicing saw (manufactured by Disco, model name DAD-2H / 6T), immersed in hydrochloric acid to remove aluminum, and then peeled off from the silicon wafer. It dried and it was set as the strip-shaped film sample.

(Evaluation of 5% thermal weight loss temperature)
A so-called 5% thermogravimetric decrease temperature was measured as an index of the amount of volatile components generated when this film sample was heated. Specifically, using a thermogravimetric analyzer (manufactured by Shimadzu Corporation, model name TGA-50), the weight change when the film sample is heated at a constant heating rate is measured, and the weight is reduced by 5% from the initial value. The temperature to be determined was determined. The measurement conditions are an initial sample weight of 20 mg, a measurement temperature range of 25 ° C. to 450 ° C., a temperature increase rate of 10 ° C./min, and a nitrogen atmosphere. The results are shown in Table 1.
In Comparative Example 1 and Comparative Example 2, the 5% thermogravimetric decrease temperature stays at 310 ° C. or lower, whereas in Examples 1 to 3, both show 360 ° C. or higher, and the amount of volatiles from the resin film is It turns out that it is decreasing.

(Creating relief pattern)
The photosensitive resin composition of Example 4 was spin-coated on a 5-inch silicon wafer and dried to form a 47 μm thick coating film. This coating film was irradiated with energy of 350 mJ / cm ² by an i-line stepper NSR2005i8A (manufactured by Nikon Corporation, Japan) using a reticle with a test pattern. Next, the coating film formed on the silicon wafer is spray-developed with a developing machine (D-SPIN636 type, manufactured by Dainippon Screen Mfg. Co., Ltd.) using cyclopentanone, and rinsed with propylene glycol methyl ether acetate. A relief pattern comprising a polyamic acid ester was obtained.
The wafer with the relief pattern formed thereon was heat-treated at 200 ° C. for 2 hours in a nitrogen atmosphere using a temperature-programmed cure furnace (VF-2000 type, manufactured by Koyo Lindberg Co., Ltd., Japan). The resulting cured relief pattern was obtained on a silicon wafer.

About each obtained pattern, the width | variety of the pattern shape and the pattern part was observed under the optical microscope, and the resolution was calculated | required. Regarding the resolution, a pattern having a plurality of openings with different areas is formed by the above method by exposing through a reticle with a test pattern, and the area of the obtained pattern opening is equal to the corresponding pattern mask opening area. If it is 1/2 or more, it is considered that it has been resolved, and the length of the opening side of the mask corresponding to the resolved opening having the smallest area is taken as the resolution. The resolution is good if it is 47 μm or less, that is, if the aspect ratio (film thickness after coating and drying / resolution) is 1 or more.
The resolution of the polyimide coating film obtained from the composition was 45 μm when the film thickness after coating and drying was 47 μm, the aspect ratio was 1 or more, and each pattern accuracy was good.

  ADVANTAGE OF THE INVENTION According to this invention, the resin film in which the volatile component at the time of a heating was reduced can be obtained, and it can use suitably for protective films, such as a semiconductor device.

Claims (3)

In the photosensitive resin composition containing the isocyanuric acid derivative having a photopolymerizable unsaturated bond and a photopolymerization initiator as essential components,
(A) The polyamide is a polyamide having a structural unit represented by the following formula (1),
(B) The isocyanuric acid derivative having a photopolymerizable unsaturated bond is an ethylene oxide-modified or propylene oxide-modified isocyanuric acid derivative represented by the following formula (3), and (A) of (B) with respect to 100 parts by mass: Ri content 15-70 parts by der, photosensitive resin composition characterized that you contain (C) a photopolymerization initiator.

[Wherein, X is a tetravalent aromatic group, and the —COOR ¹ group, the —COOR ² group, and the —CONH— group are in the ortho positions to each other. Y is a divalent aromatic group, and m is an integer of 2 to 150. One of R ¹ and R ² is a monovalent organic group having a photopolymerizable unsaturated double bond represented by the following formula (2), and the other is represented by the following formula (2). It is a monovalent organic group having a photopolymerizable unsaturated double bond, or a hydrogen atom or a monovalent saturated aliphatic group having 1 to 4 carbon atoms.

(Wherein R ³ is a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and R ⁴ and R ⁵ are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms. And R ⁶ is a divalent organic group which may be linear or branched.)]

[Wherein R ⁷ is each independently a monovalent substituent represented by the formula (4).

[Wherein R ⁸ is an ethylene group or propylene group, R ⁹ is a monovalent substituent represented by the formula (5), n is an integer from 1 to 4, and p is an integer from 4 to 6. is there. q is an integer from 0 to 3, but is not 0 simultaneously for all R ⁷ .

(Wherein R ¹⁰ represents a hydrogen atom or a methyl group)]]] (1) The process of apply | coating the photosensitive resin composition of Claim 1 to a base material, and forming a coating film,
(2) A step of irradiating the obtained coating film with an actinic ray through a patterning mask to form an exposed portion,
(3) A step of dissolving and removing the unexposed part of the coating film using a developer to form a relief pattern comprising the exposed part,
(4) A step of heating the relief pattern at a temperature of 140 to 450 ° C.,
A cured relief pattern forming method comprising:   A method for manufacturing a semiconductor device, comprising the cured relief pattern forming method according to claim 2.