JP2007058017A - Photosensitive resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive resin composition having heat resistance, chemical resistance and adhesiveness to a metal as a polyimide resin film after curing, and a cured relief pattern forming method. <P>SOLUTION: The photosensitive resin composition comprises (a) 100 parts by mass of a polyamic acid ester having a repeating unit represented by formula (1), (b) 0.1-40 parts by mass of a polyamic acid ester having two repeating units represented by formulae (2), (c) 1-20 parts by mass of a photopolymerization initiator and (d) 30-600 parts by mass of a solvent, wherein X denotes at least one 6-32C tetravalent organic group; Y denotes at least one 4-30C divalent aromatic group; Y' denotes at least one group selected from the group consisting of a 4-30C divalent aliphatic group and a divalent silicon-containing group in which the number of silicon atoms is 2-50; and R and R' each independently denote a monovalent group having an olefinic double bond. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat-sensitive photosensitive resin useful for the production of electrical / electronic materials such as semiconductor devices and multilayer wiring boards. More specifically, the present invention relates to a photosensitive polyamic acid ester composition in which a cured polyimide coating film has high metal adhesion, chemical resistance and heat resistance.

Polyimide resin is attracting attention as a material for microelectronics due to its high thermal and chemical stability, low dielectric constant, and excellent planarization ability, and is used as a semiconductor surface protective film, interlayer insulating film, or Widely used as a material for multi-chip modules.
In the case of manufacturing a semiconductor device using a polyimide resin, conventionally, a non-photosensitive polyimide precursor is applied on a substrate to form a coating film, and after heating to convert to a polyimide resin, a lithography technique is used. Thus, a method for forming a desired pattern has been used. Specifically, on the polyimide resin film, a photoresist relief pattern is formed using a photoresist and a photomask having a pattern, and then the polyimide resin film is patterned by etching. A relief pattern forming method has been used. However, in this method, first, a relief pattern of a photoresist to be a mask is formed on the polyimide resin film, and then the polyimide resin film is etched, and finally the unnecessary photoresist is removed. The process was complicated because it had to be done. In addition, since it is an indirect relief pattern forming method, the resolution is low, and it is necessary to use a toxic substance such as hydrazine as a solvent for etching.

  In recent years, in order to overcome the above problems, a method for introducing a photopolymerizable photosensitive group into a polyimide precursor and directly forming a relief pattern on a coating film of the polyimide precursor has been developed and put into practical use. . For example, a polyimide precursor formed by bonding a compound having a double bond to a polyamic acid derivative through an ester bond, an amide bond, an ionic bond, or the like (hereinafter also referred to as “photosensitive polyimide precursor”), and light. A coating film is formed by applying a photosensitive resin composition containing a polymerization initiator or the like onto a substrate, and the exposed portion of the coating film of polyimide is exposed through a photomask having a pattern. A method of forming a relief pattern made of a polyimide precursor by insolubilizing the precursor and then subjecting it to a development treatment, and then converting it to a cured relief pattern made of polyimide resin by removing the photosensitive group component by heating. Has been proposed (see Non-Patent Document 1). This technology is generally called photosensitive polyimide technology. Since the photosensitive polyimide technology overcomes the problems associated with the conventional process using a non-photosensitive polyimide precursor, in recent years, a relief pattern made of a polyimide resin is frequently formed by the photosensitive polyimide technology.

By the way, a semiconductor element (hereinafter, also simply referred to as “element”) is mounted on a printed circuit board by various methods in accordance with the purpose. The conventional element is generally a wire bonding method in which a thin wire is connected from the external terminal (pad) of the element to the lead frame. However, as the speed of the element has advanced and the operating frequency has reached to GHz, The difference in the wiring length between the terminals has led to the influence of the device operation. For this reason, when mounting elements for high-end applications, it is necessary to accurately control the length of the mounting wiring, and wire bonding makes it impossible to meet the requirements.
Accordingly, flip chip mounting has been proposed in which a rewiring layer is formed on the surface of a semiconductor chip, bumps (electrodes) are formed thereon, the chip is flipped over, and mounted directly on a printed circuit board. Flip chip mounting is used for high-end devices that handle high-speed signals because the wiring distance can be accurately controlled, and because of the small mounting size, the demand is rapidly expanding. Therefore, as a material for the rewiring layer, in addition to the excellent pattern formability and heat resistance of the photosensitive polyimide as described above, the adhesive property between the cured polyimide resin and the bump barrier metal, and the wiring metal, and Performance such as chemical resistance to resist stripping solutions used in the process is increasingly important.
However, in the conventional photosensitive polyimide technology, it has been difficult to simultaneously satisfy three of heat resistance, metal adhesion, and chemical resistance. For example, as described in Non-Patent Document 2, when a polydimethylsiloxane compound is introduced into the polyimide skeleton, the metal adhesion is improved, but the glass transition point tends to decrease due to soft polydimethylsiloxane. High heat resistance and chemical resistance were desired.

Yamaoka, Otomo, "Polyfile", 1990, 27, No. 2, pp. 14-18 N. Furukawa, Y .; Yamada and Y. Kimura, High Perform. Polym. , 8, 617, (1996).

  The present invention relates to a polyamic acid ester composition in which a cured polyimide coating film is homogeneous, has metal adhesion, chemical resistance and heat resistance at the same time, and gives a uniform relief relief pattern, and the composition An object of the present invention is to provide a method for forming a cured relief pattern using the above.

  As a result of examining the above-mentioned problems of the prior art, the present inventors have blended a polyimide precursor excellent in heat resistance and chemical resistance and a polyimide precursor having a specific structure excellent in metal adhesion. The present inventors have found that a cured relief pattern that exhibits high metal adhesion while maintaining high heat resistance and high chemical resistance can be formed on a substrate by using a functional resin composition.

（式（１）及び（２）中、Ｘは少なくとも１つの炭素数６〜３２の４価の有機基を示し、Ｙは少なくとも１つの炭素数４〜３０の２価の芳香族基を示し、Ｙ’は炭素数４〜３０の２価の脂肪族基およびケイ素数２〜５０の２価のケイ素含有基からなる群から選ばれる少なくとも１つの基を示し、ＲおよびＲ’はそれぞれ独立してオレフィン性二重結合を有する１価の基を示す。） That is, one aspect of the present invention includes (a) 100 parts by mass of a polyamic acid ester having a repeating unit represented by the following general formula (1), and (b) two repeating units represented by the following general formula (2). A photosensitive resin composition comprising 0.1 to 40 parts by mass of a polyamic acid ester, (c) 1 to 20 parts by mass of a photopolymerization initiator, and (d) 30 to 600 parts by mass of a solvent.

(In the formulas (1) and (2), X represents at least one tetravalent organic group having 6 to 32 carbon atoms, Y represents at least one divalent aromatic group having 4 to 30 carbon atoms, Y ′ represents at least one group selected from the group consisting of a divalent aliphatic group having 4 to 30 carbon atoms and a divalent silicon-containing group having 2 to 50 silicon atoms, and R and R ′ are each independently A monovalent group having an olefinic double bond is shown.)

In said photosensitive resin composition, it is preferable that (d) solvent is a solvent containing 10-100 mass% of organic solvents which have a boiling point in 150-300 degreeC.
In the second aspect of the present invention, the above-mentioned photosensitive resin composition is applied to a substrate and dried to form a coating film on the substrate, through a photomask having a pattern, or directly. A step of irradiating the film with ultraviolet rays, a step of removing the unexposed portion of the coating film by developing with a developer to form a relief pattern on the substrate, and a polyimide resin by heating the relief pattern Forming a cured relief pattern on the substrate. A method for forming a cured relief pattern, comprising:

  In the photosensitive resin composition of the present invention, the cured polyimide resin film is homogeneous and simultaneously exhibits heat resistance, chemical resistance, and metal adhesion. Furthermore, according to the method for forming a cured relief pattern of the present invention, a cured relief pattern having heat resistance, chemical resistance and metal adhesion can be formed on a substrate.

The present invention will be specifically described below.
<Photosensitive resin composition>
The component which comprises the photosensitive resin composition of this invention is demonstrated below.
(A) Polyamic acid ester, and (b) Polyamic acid ester In the photosensitive resin composition of the present invention, (a) the polyamic acid ester, and (b) the above-mentioned general formula (1) commonly contained in the polyamic acid ester The repeating unit represented by (hereinafter referred to as “A unit”) has a function of combining heat resistance and chemical resistance with the cured polyimide resin film. In addition, the repeating unit (hereinafter referred to as “B unit”) represented by the right portion of the general formula (2), which is not contained in the (a) polyamic acid ester, and is contained in the (b) polyamic acid ester. The polyimide resin film after curing has a function of giving metal adhesion. These functions are determined by selection of tetracarboxylic dianhydride and diamine which are raw materials of the polyamic acid ester. When simply referred to as a polyamic acid ester, both (a) and (b) described above are meant.
The tetracarboxylic dianhydride that can be suitably used as the main raw material of the polyamic acid ester is a tetracarboxylic dianhydride (hereinafter simply referred to as “aromatic”) in which the X group is a tetravalent aromatic group having 6 to 32 carbon atoms. Group tetracarboxylic dianhydride ").

  Preferred examples include pyromellitic dianhydride, 4,4′-oxydiphthalic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′, 4 ′. -Biphenyltetracarboxylic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxy) Phenyl) sulfide dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) ) Propane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, 1,3-bis (3,4 Dicarboxy Enoxy) benzene dianhydride, 1,4-bis (3,4-dicarboxyphenoxy) benzene dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) biphenyl dianhydride, 2,2- Bis [(3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, and 1,4,5,8-naphthalene tetracarboxylic dianhydride Etc. These aromatic tetracarboxylic dianhydrides can be used alone or in combination of two or more.

When the photosensitive resin composition of the present invention is formed into a relief pattern by irradiation with i-line, an aromatic tetracarboxylic dianhydride having good i-line permeability such as 4,4′-oxydiphthalic dianhydride is used. It is preferable to use it. In addition, when the cured polyimide resin film is used for an application requiring higher heat resistance, an aromatic tetracarboxylic dianhydride having a rigid structure such as pyromellitic dianhydride is preferable.
In addition to the aromatic tetracarboxylic dianhydride used as the main raw material, the tetracarboxylic dianhydride (hereinafter referred to simply as “aliphatic tetrahydride”) in which the X group is a tetravalent aliphatic group having 4 to 32 carbon atoms. Carboxylic dianhydride ") can also be used as an auxiliary material.

  Preferred examples include, for example, butane-1,2,3,4-tetracarboxylic dianhydride, pentane-1,2,4,5-tetracarboxylic dianhydride, cyclobutane tetracarboxylic dianhydride, cyclo Pentane-1,2,3,4-tetracarboxylic dianhydride, cyclohexane-1,2,4,5-tetracarboxylic dianhydride, cyclohex-1-ene-2,3,5,6-tetracarboxylic Acid dianhydride, 3-ethylcyclohex-1-ene-3- (1,2), 5,6-tetracarboxylic dianhydride, 1-methyl-3-ethylcyclohexane-3- (1,2) , 5,6-tetracarboxylic dianhydride, 1-methyl-3-ethylcyclohex-1-ene-3- (1,2), 5,6-tetracarboxylic dianhydride, 1-ethylcyclohexane- 1- (1,2), 3,4 Tetracarboxylic dianhydride, 1-propylcyclohexane-1- (1,2), 3,4-tetracarboxylic dianhydride, 1,3-dipropylcyclohexane-1- (2,3), 3- ( 2,3) -tetracarboxylic dianhydride, dicyclohexyl-3,4,3 ′, 4′-tetracarboxylic dianhydride, bicyclo [2.2.1] heptane-2,3,5,6-tetra Carboxylic dianhydride, bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic dianhydride, bicyclo [2.2.2] oct-7-ene-2,3,5 , 6-tetracarboxylic dianhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, and the like. These aliphatic tetracarboxylic dianhydrides can be used alone or in combination of two or more.

In the polyamic acid ester, the ratio of the X group derived from the aliphatic tetracarboxylic dianhydride to the X group derived from all the tetracarboxylic dianhydrides should be within a range where desired heat resistance and chemical resistance can be obtained. There is no particular limitation.
In the polyamic acid ester, the R and R ′ groups in the repeating unit are derived from alcohols used for the esterification reaction of the tetracarboxylic dianhydride. In order to impart photosensitivity, the alcohol preferably uses an alcohol having an olefinic double bond as a main component.
Specifically, 2-methacryloyloxyethyl alcohol, 2-acryloyloxyethyl alcohol, 1-acryloyloxy-2-propyl alcohol, 2-methacrylamide ethyl alcohol, 2-acrylamidoethyl alcohol, methylol vinyl ketone, 2-hydroxyethyl Examples include vinyl ketone, 2-hydroxyethyl methacrylate, glycerol monomethacrylate, and glycerol monoacrylate. These alcohols having an olefinic double bond can be used alone or in combination of two or more.

Examples of the alcohol having an olefinic double bond include polyethylene glycol monomethacrylate, polyethylene glycol monoacrylate, polyethylene glycol polypropylene glycol monomethacrylate, polyethylene glycol polypropylene glycol monoacrylate, and poly (ethylene glycol-tetramethylene glycol) mono. Long chain polyalkylene glycol acrylates such as acrylates can also be used.
Furthermore, alcohols having two or more olefinic double bonds in the molecule can also be suitably used. Specifically, glycerol dimethacrylate, glycerol diacrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, and the like can be given.

Further, as described in JP-A-6-80776, an olefinic double bond such as methyl alcohol, ethyl alcohol, n-propyl alcohol, or isopropyl alcohol is added to the alcohol having the olefinic double bond. You may mix and use some alcohols which do not have.
In the polyamic acid ester, the sum of R groups and R ′ groups derived from alcohols having no olefinic double bond is 0 to 30 mol relative to the sum of R groups and R ′ groups derived from all alcohols. % Is preferably within the range of 0 to 10 mol%, and most preferably 0 mol%. When the sum of the R group and R ′ group derived from alcohols having no olefinic double bond is 30 mol% or less, the lithography performance is excellent.
Stoichiometrically, the amount of alcohol used for esterification of tetracarboxylic dianhydride is 1.00 equivalent (monovalent) per 1.00 equivalent (0.50 mol) of tetracarboxylic dianhydride. However, when synthesizing a polyamic acid ester, 1.01 to 1.10 equivalents of alcohol per 1.00 equivalent of tetracarboxylic dianhydride is used to synthesize tetracarboxylic acid. It is preferable to synthesize a diester because the storage stability of the finally obtained photosensitive resin composition is improved.

Next, the Y group of the polyamic acid ester will be described.
The Y group is a divalent aromatic group having 4 to 30 carbon atoms and is derived from aromatic diamines used as raw materials. By introducing an aromatic group into the diamine together with the tetracarboxylic dianhydride described above, the heat resistance of the cured polyimide resin film can be increased.
Specific examples of aromatic diamines include paraphenylene diamine, metaphenylene diamine, 4,4'-diaminodiphenyl ether, 4,4'-methylenebis (2-methylaniline), 4,4'-diaminodiphenyl sulfide, 4,4′-diaminobenzophenone, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl sulfone, 3,3′-diaminodiphenyl sulfone, 4,4′-diaminodiphenyl sulfoxide, 3,3′- Dimethyl-4,4′-diaminobiphenyl, 2,2′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dimethoxy-4,4′-diaminobiphenyl, 3,3′-dichloro-4,4 '-Diaminobiphenyl, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) ) Benzene, 1,3-bis (3-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether, 1,4-bis (4-aminophenyl) benzene, 9 , 10-bis (4-aminophenyl) anthracene, 1,1,1,3,3,3-hexafluoro-2,2-bis (4-aminophenyl) propane, 1,1,1,3,3 3-hexafluoro-2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,1,1,3,3,3-hexafluoro-2,2-bis (3-amino 4-methylphenyl) propane, 1,4-bis (3-aminopropyldimethylsilyl) benzene, or some of the hydrogen atoms directly bonded to the aromatic ring of these aromatic diamines are methyl, ethyl, and Examples thereof include those substituted with a group selected from the group consisting of halogen groups.

Among these, as an aromatic diamine more preferable as a raw material of the A unit of the polyamic acid ester of the component (a), an alkyl group is present on an aromatic ring such as 4,4′-methylenebis (2-methylaniline). Things.
Among them, 4,4′-diaminodiphenyl ether or 3,3′-dimethyl-4,4′-diamino is more preferable as an aromatic diamine as a raw material for the A unit of the polyamic acid ester of component (b). Aromatic diamines having two non-condensed benzene rings such as biphenyl can be mentioned. A photosensitive resin composition containing a polyamic acid ester using such aromatic diamines has improved temporal stability.
Any of the above aromatic diamines can be used alone or in admixture of two or more.
When the photosensitive resin composition of the present invention is formed into a relief pattern by i-ray irradiation, i-ray transmissive properties such as bis (4- (4-aminophenoxy) phenyl) sulfone and 4,4′-diaminodiphenyl ether are used. It is preferred to use good aromatic diamines.
Similarly to the case of the Y group, the Y ′ group of the B unit is derived from diamines used as raw materials. The diamine is preferably a diamine having at least one group selected from the group consisting of a divalent aliphatic group having 4 to 30 carbon atoms and a divalent silicon-containing group having 2 to 50 silicon atoms.
Examples of the divalent aliphatic group having 4 to 30 carbon atoms include aliphatic diamines having an acyclic structure (hereinafter simply referred to as “aliphatic diamines”) or diamines having an alicyclic structure (hereinafter referred to as “aliphatic diamines”). And simply referred to as “alicyclic diamines”).

  Specific examples of the aliphatic diamines include ethylene glycol diamines such as bis (aminomethyl) ether, bis (2-aminoethyl) ether, bis (3-aminopropyl) ether, and bis (2-aminomethoxy) ethyl. ] Ether, bis [2- (2-aminoethoxy) ethyl] ether, bis [2- (3-aminoprotoxy) ethyl] ether, 1,2-bis (aminomethoxy) ethane, 1,2-bis (2 -Aminoethoxy) ethane, 1,2-bis [2- (aminomethoxy) ethoxy] ethane, 1,2-bis [2- (2-aminoethoxy) ethoxy] ethane, ethylene glycol bis (3-aminopropyl) ether , Diethylene glycol bis (3-aminopropyl) ether, triethylene glycol bis (3-aminopropyl) Ether, methylenediamine, ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diamino Examples include octane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane. These aliphatic diamines may be used alone or in combination of two or more.

  Specific examples of the alicyclic diamines include, for example, isophorone diamine, 4,4′-diaminodicyclohexylmethane, 1,8-diamino-p-menthane, 1,4-cyclohexanebis (methylamine), 1,3- Cyclohexanebis (methylamine), 2,5-diaminomethyl-bicyclo [2,2,2] octane, 2,5-diaminomethyl-7,7-dimethylbicyclo [2,2,1] heptane, 2,5- Diaminomethyl-7,7-difluorobicyclo [2,2,1] heptane, 2,5-diaminomethyl-7,7,8,8-tetrafluorobicyclo [2,2,2] octane, 2,5-diamino Methyl-7,7-bis (hexafluoromethyl) bicyclo [2,2,1] heptane, 2,5-diaminomethyl-7-oxabicyclo [2,2,1] hepta 2,5-diaminomethyl-7-thiabicyclo [2,2,1] heptane, 2,5-diaminomethyl-7-oxobicyclo [2,2,1] heptane, 2,5-diaminomethyl-7-azabicyclo [2,2,1] heptane, 2,6-diaminomethyl-bicyclo [2,2,2] octane, 2,6-diaminomethyl-7,7-dimethylbicyclo [2,2,1] heptane, 2, 6-diaminomethyl-7,7-difluorobicyclo [2,2,1] heptane, 2,6-diaminomethyl-7,7,8,8-tetrafluorobicyclo [2,2,2] octane, 2,6 -Diaminomethyl-7,7-bis (hexafluoromethyl) bicyclo [2,2,1] heptane, 2,6-diaminomethyl-7-oxybicyclo [2,2,1] heptane, 2,6-diaminomethyl 7-thiobicyclo [2,2,1] heptane, 2,6-diaminomethyl-7-oxobicyclo [2,2,1] heptane, 2,6-diaminomethyl-7-iminobicyclo [2,2,1] Heptane, 2,5-diamino-bicyclo [2,2,1] heptane, 2,5-diamino-bicyclo [2,2,2] octane, 2,5-diamino-7,7-dimethylbicyclo [2,2 , 1] heptane, 2,5-diamino-7,7-difluorobicyclo [2,2,1] heptane, 2,5-diamino-7,7,8,8-tetrafluorobicyclo [2,2,2] Octane, 2,5-diamino-7,7-bis (hexafluoromethyl) bicyclo [2,2,1] heptane, 2,5-diamino-7-oxabicyclo [2,2,1] heptane, 2,5 -Diamino-7-thiabicyclo [2,2,1] heptane, 2,5-diamino-7-oxobicyclo [2,2,1] heptane, 2,5-diamino-7-azabicyclo [2,2,1] heptane, 2,6- Diamino-bicyclo [2,2,1] heptane, 2,6-diamino-bicyclo [2,2,2] octane, 2,6-diamino-7,7-dimethylbicyclo [2,2,1] heptane, 2 , 6-Diamino-7,7-difluorobicyclo [2,2,1] heptane, 2,6-diamino-7,7,8,8-tetrafluorobicyclo [2,2,2] octane, 2,6- Diamino-7,7-bis (hexafluoromethyl) bicyclo [2,2,1] heptane, 2,6-diamino-7-oxybicyclo [2,2,1] heptane, 2,6-diamino-7-thiobicyclo [2,2,1] heptane, 2,6 Diamino-7-oxobicyclo [2,2,1] heptane, 2,6-diamino-7-iminobicyclo [2,2,1] heptane, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1, 4-diaminocyclohexane, 1,2-di (2-aminoethyl) cyclohexane, 1,3-di (2-aminoethyl) cyclohexane, 1,4-di (2-aminoethyl) cyclohexane, bis (4-aminocyclohexyl) ) Methane, 3,9-bis (3-aminopropyl) -2,4,8,10-tetraoxaspiro [5,5] undecane, bicyclo [2,2,1] heptanebismethylamine, and And the compounds represented. These alicyclic diamines may be used alone or in combination of two or more.

（式中、Ｒ₁およびＲ₄は二価の炭化水素基を示し、それぞれ同一でも異なっていてもよく、Ｒ₂およびＲ₃は一価の炭化水素基を示し、それぞれ同一でも異なっていてもよく、ｐは１以上の整数を表す。） As the diamine having a divalent silicon-containing group having 2 to 50 silicon atoms (hereinafter simply referred to as “silicon-containing diamine”), for example, diamino (poly) siloxane represented by the following formula is preferably used. Can do.

(Wherein R ₁ and R ₄ represent a divalent hydrocarbon group, which may be the same or different, and R ₂ and R ₃ represent a monovalent hydrocarbon group, which may be the same or different, respectively. Well, p represents an integer of 1 or more.)

Preferable structures of R ₁ and R ₄ include a methylene group, an ethylene group, a propylene group, a butylene group, and a phenylene group. Preferred examples of R ₂ and R ₃ include methyl group, ethyl group, propyl group, butyl group, and phenyl group.
In the B unit, the diamine used as a raw material for Y ′ preferably contains a silicon-containing diamine from the viewpoint of improving metal adhesion. (B) In the polyamic acid ester, if the number of moles of the B unit is 1% or more of the total number of moles of the A unit and the B unit, the metal adhesion is improved. Moreover, if the number of moles of the B unit is 50% or less of the total number of moles of the A unit and the B unit, the heat resistance and the chemical resistance are improved.
The number average molecular weight of the polyamic acid ester is preferably 3000 to 100,000, more preferably 3000 to 50000. When the molecular weight is 3000 or more, heat resistance and strength are improved, and when it is 100,000 or less, solubility in a solvent is improved.

The polyamic acid ester can be synthesized by any known acid chloride method, DCC method, or isoimide method.
The ratio of (a) polyamic acid ester to (b) polyamic acid ester is preferably 0.1 to 40 parts by mass of (b) polyamic acid ester with respect to 100 parts by mass of (a) polyamic acid ester. It is more preferably 3 to 20 parts by mass, and most preferably 0.5 to 10 parts by mass. (B) When the polyamic acid ester is 0.1 part by mass or more, the adhesiveness with the metal is improved. Moreover, when (b) polyamic acid ester is 40 mass parts or less, compatibility with (a) polyamic acid ester (a) improves and it is easy to obtain a uniform coating film.
As described above, the heat resistance and chemical resistance of the cured polyimide resin film are kept high by controlling the molecular weight of tetracarboxylic dianhydride and diamine, which are raw materials constituting the polyamic acid ester, and the entire polyamic acid ester. The physical properties that have been difficult to achieve with the conventionally known photosensitive polyimide technology of improving the metal adhesiveness as it is are achieved.

(C) Photopolymerization initiator Although the photosensitive resin composition of the present invention has photosensitivity derived from the double bond of the polyamic acid ester, the photosensitivity is further improved by adding a photopolymerization initiator. It is preferable.
Specific examples of the photopolymerization initiator include, for example, benzophenone, methyl o-benzoylbenzoate, 4-benzoyl-4′-methyldiphenylketone, dibenzylketone, benzophenone derivatives such as fluorenone, 2,2′-diethoxyacetophenone, Acetophenone derivatives such as 2-hydroxy-2-methylpropiophenone, 1-hydroxycyclohexyl phenyl ketone, thioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, thioxanthone derivatives such as diethylthioxanthone, benzyl, benzyldimethyl ketal, benzyl-β -Benzyl derivatives such as methoxyethyl acetal, benzoin derivatives such as benzoin methyl ether, 2,6-di (4'-diazidobenzal) -4-methylcyclohexanone, 2,6'-di Azides such as 4′-diazidobenzal) cyclohexanone, 1-phenyl-1,2-butanedione-2- (O-methoxycarbonyl) oxime, 1-phenylpropanedione-2- (O-methoxycarbonyl) oxime, 1-phenyl Propanedione-2- (O-ethoxycarbonyl) oxime, 1-phenylpropanedione-2- (O-benzoyl) oxime, 1,3-diphenylpropanetrione-2- (O-ethoxycarbonyl) oxime, 1-phenyl- Oximes such as 3-ethoxypropanetrione-2- (O-benzoyl) oxime, N-arylglycines such as N-phenylglycine, peroxides such as benzoyl peroxide, aromatic bisimidazoles, titanocenes, etc. Oximes are preferred in terms of photosensitivity. Arbitrariness. As for the addition amount of these photoinitiators, 1-20 mass parts is preferable with respect to 100 mass parts of (a) polyamic-acid ester.

(D) Solvent Preferred examples of the good solvent for the polyamic acid ester include N, N-dimethylformamide, N-methylpyrrolidone (hereinafter also referred to as NMP), N-ethyl-2-pyrrolidone, N, N-dimethylacetamide. , Diethylene glycol dimethyl ether, cyclopentanone, γ-butyrolactone, α-acetyl-γ-butyrolactone, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone, and the like. Or it can be used in combination of 2 or more types.
Other preferred examples include lactic acid esters such as ethyl lactate and butyl lactate, propylene glycol monoalkyl ethers, 2-hydroxyisobutyric acid esters, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, Hydrocarbons such as benzyl benzoate, diethylbenzene, diamylbenzene, triamylbenzene, amyltoluene, p-cymene, alcohols such as n-heptanol, n-octanol, n-decanol, ethylphenyl ether, n-butylphenyl ether And ethers such as methyl-n-hexyl ketone and diisobutyl ketone, and examples thereof include organic solvents having a boiling point at 150 to 300 ° C.
The organic solvent having a boiling point at 150 to 300 ° C. is preferably 10 to 100% by mass with respect to the total mass of the solvent.

Further, it is also preferable to add a block copolymer type surfactant as an additive to the solvent. Specifically, binary block copolymers such as polyethylene glycol / polypropylene glycol, polyethylene glycol / polybutylene glycol, and further polyethylene glycol / polypropylene glycol / polyethylene glycol, polypropylene glycol / polyethylene glycol / polypropylene glycol, polyethylene glycol / polybutylene. And polyether block copolymers such as linear ternary block copolymers such as glycol / polyethylene glycol.
Furthermore, as a branched block copolymer, a structure in which at least three hydroxyl groups contained in sugar chains typified by glycerol, erythritol, pentaerythritol, pentitol, pentose, hexitol, hexose, heptose and the like are combined with a polymer chain And / or a structure in which at least three of hydroxyl groups and carboxyl groups contained in hydroxyl acid are bonded to the block copolymer chain. Specifically, a compound in which a polyethylene glycol / polypropylene glycol block copolymer is bonded to three hydroxyl groups of glycerol, and a block copolymer of polyethylene glycol / polypropylene glycol / polyethylene glycol / polypropylene glycol is bonded to three or four hydroxyl groups of erythritol. And the like.

Specific examples of the sugar chain used to obtain the above branched block copolymer include sorbitol, mannitol, xylitol, threitol, maltitol, arabitol, lactitol, adonitol, cellobiitol, glucose, fructose, sucrose, lactose, Mannose, galactose, erythrose, xylulose, allulose, ribose, sorbose, xylose, arabinose, isomaltose, dextrose, glucoheptose and the like can be mentioned.
Specific examples of hydroxyl acid include citric acid, malic acid, tartaric acid, gluconic acid, glucuronic acid, glucoheptonic acid, glucooctanoic acid, threonic acid, saccharic acid, galactonic acid, galactaric acid, galacturonic acid, glyceric acid. And hydroxysuccinic acid.
These solvents (including the above-mentioned additives) can be appropriately added to the photosensitive resin composition of the present invention not only for obtaining a uniform composition but also depending on the coating film thickness and viscosity. (A) It is preferable to use in the range of 30-600 mass parts with respect to 100 mass parts of polyamic acid ester.
Furthermore, in order to improve the storage stability over time of the photosensitive resin composition of the present invention, the following specific alcohols can be used in addition to the above.

  Specific examples of the specific alcohols include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, t-butyl alcohol, ethyl lactate, butyl lactate, propylene glycol-1 -Methyl ether, propylene glycol-2-methyl ether, propylene glycol-1-ethyl ether, propylene glycol-2-ethyl ether, propylene glycol-1- (n-propyl) ether, propylene glycol-2- (n-propyl) Ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, monoalcohols such as ethylene glycol-n-propyl ether, diethylene glycol such as ethylene glycol and propylene glycol Alcohol compounds can be mentioned. Among these, ethyl lactate, butyl lactate, propylene glycol-1-methyl ether, propylene glycol-1-ethyl ether, and propylene glycol-1- (n-propyl) ether are more preferable. The content of the specific alcohol in the solvent is preferably 0.1 to 80% by mass, more preferably 10 to 70% by mass. When the content of the specific alcohol is 0.1% by mass or more, the storage stability of the photosensitive resin composition is good, and when it is 80% by mass or less, the solubility of the polyamic acid ester is good.

(E) Other components In order to further improve the photosensitivity, a compound having a reactive carbon-carbon double bond that does not correspond to the component (a) can be added to the photosensitive resin composition of the present invention. . Such compounds include 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, ethylene glycol diacrylate, polyethylene glycol diacrylate (2-20 moles of ethylene monomer units), pentaerythritol diacrylate, dipenta Examples include erythritol hexaacrylate, tetramethylolmethane tetraacrylate, methylenebisacrylamide, N-methylolacrylamide, and compounds obtained by substituting acrylate or acrylamide with methacrylate or methacrylamide, respectively. The compound having such a reactive carbon-carbon double bond is preferably added in the range of 1 to 90 parts by mass with respect to 100 parts by mass of the (a) polyamic acid ester.

  To further improve the photosensitivity, a sensitizer can be added to the photosensitive resin composition of the present invention. Examples of the sensitizer include Michler's ketone, 4,4′-bis (diethylamino) benzophenone, 2,5-bis (4′-diethylaminobenzal) cyclopentane, and 2,6-bis (4′-diethylaminobenzal). Cyclohexanone, 2,6-bis (4′-diethylaminobenzal) -4-methylcyclohexanone, 4,4′-bis (dimethylamino) chalcone, 4,4′-bis (diethylamino) chalcone, p-dimethylaminocinnamyl Denindanone, p-dimethylaminobenzylideneindanone, 2- (p-dimethylaminophenylbiphenylene) -benzothiazole, 2- (p-dimethylaminophenylvinylene) benzothiazole, 2- (p-dimethylaminophenylvinylene) iso Naphthiazole, 1,3-bis (4′- Methylaminobenzal) acetone, 1,3-bis (4′-diethylaminobenzal) acetone, 3,3′-carbonyl-bis (7-diethylaminocoumarin), 3-acetyl-7-dimethylaminocoumarin, 3-ethoxy Carbonyl-7-dimethylaminocoumarin, 3-benzyloxycarbonyl-7-dimethylaminocoumarin, 3-methoxycarbonyl-7-diethylaminocoumarin, 3-ethoxycarbonyl-7-diethylaminocoumarin, N-phenyl-N′-ethylethanolamine N-phenyldiethanolamine, Np-tolyldiethanolamine, N-phenylethanolamine, 4-morpholinobenzophenone, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, 2-mercaptobenzimidazo 1-phenyl-5-mercaptotetrazole, 2-mercaptobenzothiazole, 2- (p-dimethylaminostyryl) benzoxazole, 2- (p-dimethylaminostyryl) benzthiazole, 2- (p-dimethylaminostyryl) Examples thereof include naphtho (1,2-d) thiazole and 2- (p-dimethylaminobenzoyl) styrene.

From the viewpoint of sensitivity, it is preferable to use a combination of a sensitizer having a mercapto group and a sensitizer having a dialkylaminophenyl group. These can be used alone or in combination of 2 to 5 kinds. The sensitizer for improving the photosensitivity is preferably used in an amount of 0.1 to 50 parts by mass with respect to (a) 100 parts by mass of the polyamic acid ester.
In addition, an adhesion aid can be added to the photosensitive resin composition of the present invention in order to improve the adhesion to the substrate. Adhesion aids include γ-aminopropyldimethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, 3- Methacryloxypropyldimethoxymethylsilane, 3-methacryloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinopropylsilane, diethoxy-3-glycidoxypropylmethylsilane, N- (3-diethoxymethylsilylpropyl) succinimide N- [3- (triethoxysilyl) propyl] phthalimidic acid, benzophenone-3,3′-bis (N- [3-triethoxysilyl] propylamide) -4,4′-dicarboxylic acid, and benzene-1 , 4-bis (N- [3-tri Toxisilyl] propylamide) -2,5-dicarboxylic acid and other silane coupling agents, and aluminum-based adhesion aids such as aluminum tris (ethyl acetoacetate), aluminum tris (acetylacetonate), and ethyl acetoacetate aluminum diisopropylate Agents and the like. In these, it is more preferable to use a silane coupling agent from the point of adhesive force. The addition amount of the adhesion assistant is preferably in the range of 0.5 to 50 parts by mass with respect to (a) 100 parts by mass of the polyamic acid ester.

In addition, a thermal 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 thermal 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-phenylhydroxylamine ammonium salt, N-nitroso-N- (1-naphthyl) hydroxylamine ammonium salt, and the like are used. As a quantity of a thermal-polymerization inhibitor, the range of 0.005-30 mass parts is preferable with respect to 100 mass parts of (a) polyamic-acid ester.
The photosensitive resin composition of the present invention can be obtained by mixing the above-described components in any order. Moreover, components other than the polyamic acid ester may be dissolved in a solvent in advance, and then the polyamic acid ester may be dissolved.

<Method for forming cured relief pattern>
As one aspect of the method of forming the cured relief pattern which consists of a polyimide resin from the photosensitive resin composition of this invention, the following processes are preferable.
(I) The process of forming a coating film on this base material by apply | coating said photosensitive resin composition to a base material, and drying.
(Ii) A step of irradiating the coating film with ultraviolet rays through a photomask having a pattern or directly.
(Iii) A step of removing an unexposed portion of the coating film by developing with a developer, thereby forming a relief pattern on the substrate.
(Iv) A step of imidizing the polyamic acid ester in the pattern by heating the relief pattern, thereby forming a cured relief pattern made of a polyimide resin on the substrate.

Examples of the substrate that can be used in the method for forming a cured relief pattern of the present invention include a silicon wafer, a metal, glass, a semiconductor, a metal oxide insulating film, and silicon nitride. A silicon wafer is preferably used. The thickness of the substrate is preferably 200 μm to 800 μm, but is not limited thereto.
As a method for applying the photosensitive resin composition of the present invention on a substrate, methods conventionally used for applying a photosensitive resin composition, for example, spin coater, bar coater, blade coater, curtain coater, or A method of applying with a screen printer or the like, or a method of applying with a spray coater can be used.
As a method for drying the coating film, methods such as air drying, heat drying with an oven or hot plate, and vacuum drying are used. Moreover, it is desirable to dry the coating film under conditions that do not cause imidation of the polyamic acid ester in the composition. Specifically, when air drying or heat drying is performed, it is preferably performed at 20 ° C. to 140 ° C. for 1 minute to 1 hour.
The coating film thus obtained is subjected to pattern exposure with an ultraviolet light source or the like using an exposure apparatus such as a contact aligner, mirror projection, or stepper, and then developed.

As the developer used for development, a good solvent for the polyamic acid ester or a combination of the good solvent and the poor solvent is preferable. The selection of the good solvent and the poor solvent is affected by the chemical structure in the polyamic acid ester, the molecular weight of the ester, and the like.
Preferable good solvents include N-methylpyrrolidone, N-cyclohexyl-2-pyrrolidone, N, N-dimethylacetamide, cyclopentanone, cyclohexanone, γ-butyrolactone, and α-acetyl-γ-butyrolactone. As the poor solvent, toluene, xylene, methanol, ethanol, isopropyl alcohol, ethyl lactate, propylene glycol methyl ether acetate, water and the like are preferable. When a good solvent and a poor solvent are mixed and used, the ratio of the poor solvent to the good solvent is adjusted by the solubility of the polyamic acid ester. Moreover, several types of solvents can be used in combination.
As a method for development, an arbitrary method can be selected and used from conventionally known photoresist development methods, for example, a rotary spray method, a paddle method, an immersion method involving ultrasonic treatment, and the like. .

By heating the relief pattern of the polyamic acid ester obtained as described above and dispersing and imidizing the photopolymerized group having an olefinic double bond, a cured relief pattern made of a polyimide resin is obtained. Convert. Various methods such as a method using a hot plate, a method using an oven, and a method using a temperature rising oven capable of setting a temperature program can be selected as a method for heat conversion. Heating can be performed at 280 ° C. to 450 ° C. for 30 minutes to 5 hours. Air may be used as the atmospheric gas for heat conversion, and an inert gas such as nitrogen or argon may be used.
As described above, a bump or rewiring metal layer (titanium, aluminum, etc.) is further provided on the cured relief pattern made of polyimide resin obtained on the base material by a thin film preparation method such as sputtering. Thus, a semiconductor device for bump or rewiring can be manufactured. Note that a known surface treatment such as ashing or plasma etching may be performed before providing the metal layer.

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples and the like.
The properties of the polyamic acid ester or the coating film were measured and evaluated according to the following method.
(1) Measurement of number average molecular weight (Mn) of polyamic acid ester The number average molecular weight (Mn) of the polyamic acid ester was measured by a gel permeation chromatography method (standard polystyrene conversion).
(2) Measurement of glass transition temperature (Tg) of polyimide coating film On a 5-inch silicon wafer (produced by Fujimi Electronics Co., Ltd., Japan) having a thickness of 625 μm ± 25 μm as a substrate, the film thickness after curing is about 10 μm. After the photosensitive resin composition was spin-coated so as to be, a heat-cured polyimide coating film was obtained by heating at 350 ° C. for 2 hours in a nitrogen atmosphere. The obtained polyimide coating film was peeled off from the silicon wafer to obtain a polyimide tape. The resulting polyimide tape 200 g / mm ² load and thermomechanical testing device in the range of 20 to 500 ° C. at a heating rate 10 ° C. / min (Shimadzu Corporation: TMA-50) by measured, the horizontal axis displaced temperature The tangential intersection of the thermal yield points of the polyimide tape in the measurement chart with the amount on the vertical axis was defined as Tg.

(3) Evaluation of resolution of cured relief pattern The photosensitive resin composition was spin-coated on a 5-inch silicon wafer and dried to form a 10 μm thick coating film. This coating film was irradiated with energy of 300 mJ / cm ² using an i-line stepper NSR2005i8A (Nikon Corporation, Japan) using a reticle with a test pattern. Subsequently, the coating film formed on the wafer is spray-developed with a developing machine (D-SPIN636 type, manufactured by Dainippon Screen Mfg. Co., Ltd.) using cyclopentanone as a developer, and rinsed with propylene glycol methyl ether acetate. A relief pattern was obtained.
The wafer on which the relief pattern was formed was heat-treated in a nitrogen atmosphere at 200 ° C. for 1 hour and subsequently at 350 ° C. for 2 hours using a temperature rising programmed curing furnace (VF-2000 type, manufactured by Koyo Lindberg, Japan). As a result, a cured relief pattern made of a polyimide resin having a thickness of about 5 μm was obtained on the silicon wafer.
About the obtained hardening relief pattern, the pattern shape and the width | variety of the pattern part were 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 resulting polyimide resin pattern opening is the corresponding pattern reticle opening. If the area is ½ or more of the area, it is regarded as resolved, and the length of the opening side of the reticle corresponding to the resolved opening having the smallest area is defined as the resolution. A resolution of 10 μm or less was considered good.

(4) Evaluation of chemical resistance of cured relief pattern The photosensitive resin composition was spin-coated on a 5-inch silicon wafer and dried to form a 10 μm thick coating film. This coating film was irradiated with energy of 300 mJ / cm ² using a reticle with a test pattern by an i-line stepper: NSR2005i8A (manufactured by Nikon Corporation, Japan). Subsequently, the coating film formed on the wafer is spray-developed with a developing machine (D-SPIN636 type, manufactured by Dainippon Screen Mfg. Co., Ltd.) using cyclopentanone as a developer, and rinsed with propylene glycol methyl ether acetate. A relief pattern was obtained.
The wafer on which the relief pattern was formed was heat-treated in a nitrogen atmosphere at 200 ° C. for 1 hour and subsequently at 350 ° C. for 2 hours using a temperature rising programmed curing furnace (VF-2000 type, manufactured by Koyo Lindberg, Japan). As a result, a cured relief pattern made of polyimide resin having a thickness of 5 μm was obtained on the silicon wafer.
About the obtained cured relief pattern, the weight ratio of tetramethylammonium hydroxide (TMAH) / dimethylsulfoxide (DMSO) was 6/94 in a sulfolane / NMP / propanolamine mixed solution (PRS-3000) at 85 ° C. for 1 hour. The mixed solution was permeated at 60 ° C. for 40 minutes, the surface pattern was observed, and a chemical resistance test was performed. If there was no dissolution of the pattern, peeling of the pattern, or cracking of the coating film, the test was accepted.

(5) Evaluation of metal adhesion of polyimide coating film On a 5-inch silicon wafer (manufactured by Fujimi Electronics Co., Ltd., Japan) having a thickness of 625 μm ± 25 μm serving as a substrate, the film thickness after curing is about 10 μm. After spin-coating the photosensitive resin composition, a polyimide coating film was obtained by heating at 350 ° C. for 2 hours in a nitrogen atmosphere and thermosetting.
Low pressure plasma treatment is performed on this polyimide coating using an ashing device (EXAM, manufactured by Shinko Seiki Co., Ltd.) under conditions of oxygen: carbon tetrafluoride flow rate of 40 ml / min: 1 ml / min, 50 Pa, 133 W. It was. The polyimide coating film was subjected to argon plasma etching under the conditions of an argon flow rate of 50 sccm, 1 Pa, and 400 W using a sputtering apparatus (L-430S-FH, manufactured by Anelva). Further, an Al or Ti film having a thickness of 200 nm was formed on the polyimide coating film using a sputtering apparatus (L-430S-FH, manufactured by Anelva). On this Al or Ti film, an epoxy adhesive (made by Showa Polymer Co., Ltd., Araldite Standard) was used to bond a pin having a diameter of 2 mm, and this was pulled using a tensile tester (quad group, Sebastian type 5). A peel test was performed. If the force required for peeling was 60 Mpa or more, it was determined to be acceptable.

<Synthesis Example 1>
(Synthesis of polyamic acid ester A)
Pyromellitic dianhydride (PMDA) 109.1g was put into a 2 liter separable flask, 13-g 2-hydroxyethyl methacrylate (HEMA) and γ-butyrolactone 400ml were added and stirred at room temperature. While adding 79.1 g of pyridine, a reaction mixture was obtained. After completion of the exothermic reaction, the mixture was allowed to cool to room temperature and left for 16 hours. Next, under ice cooling, a solution prepared by dissolving 206.3 g of dicyclohexylcarbodiimide (DCC) in 200 ml of γ-butyrolactone was added to the reaction mixture over 40 minutes with stirring. This reaction solution was placed in a 5 liter separable flask in which 103.7 g of 4,4′-methylenebis (2-methylaniline) (MBA) was suspended in 200 ml of γ-butyrolactone for 60 minutes while stirring in ice cooling. Added over.
After further stirring at room temperature for 4 hours, 240 ml of ethyl alcohol was added and stirred for 1 hour, and then 7000 ml of γ-butyrolactone was added. The precipitate generated in the reaction mixture was removed by filtration to obtain a reaction solution. The obtained reaction solution was added to 10 liters of ethyl alcohol to produce a precipitate consisting of a crude polymer. The produced crude polymer was separated by filtration and dissolved in 1.5 L of NMP to obtain a crude polymer solution. The crude polymer solution was dropped into 28 liters of water to precipitate the polymer, and the resulting precipitate was filtered off and dried in vacuo to obtain a powdered polymer (polyamic acid ester A). The number average molecular weight (Mn) of the polyamic acid ester A was measured by gel permeation chromatography (converted to standard polystyrene) and found to be 16000.

<Synthesis Example 2>
(Synthesis of polyamic acid ester B)
Pyromellitic dianhydride (PMDA) 109.1g was put into a 2 liter separable flask, 13-g 2-hydroxyethyl methacrylate (HEMA) and γ-butyrolactone 400ml were added and stirred at room temperature. While adding 79.1 g of pyridine, a reaction mixture was obtained. After completion of the exothermic reaction, the mixture was allowed to cool to room temperature and left for 16 hours. Next, under ice cooling, a solution prepared by dissolving 206.3 g of dicyclohexylcarbodiimide (DCC) in 200 ml of γ-butyrolactone was added to the reaction mixture over 40 minutes with stirring. This reaction solution was added to a 5 liter separable flask in which 74.4 g of 4,4′-diaminodiphenyl ether (DADPE) was suspended in 200 ml of γ-butyrolactone with stirring in ice cooling over 60 minutes ( Reaction solution 1).

Next, with stirring, a solution of 92.9 g of α, ω-aminopropyl polydimethylsiloxane having a number average molecular weight of 1000 (manufactured by Chisso Corporation, Silaplane, FM3311) in 312 ml of γ-butyrolactone and 78 ml of butyl benzoate is stirred. It added over 60 minutes (reaction liquid 2).
The reaction solution 2 was added to the reaction solution 1 over 60 minutes with stirring in ice-cooling, and further stirred at room temperature for 4 hours. Then, 240 ml of ethyl alcohol was added and stirred for 1 hour, and then 7000 ml of γ-butyrolactone. Was added. The precipitate generated in the reaction mixture was removed by filtration to obtain a reaction solution. The obtained reaction solution was added to 10 liters of ethyl alcohol to produce a precipitate consisting of a crude polymer. The produced crude polymer was separated by filtration and dissolved in 1.5 liter of tetrahydrofuran to obtain a crude polymer solution. The crude polymer solution was dropped into 28 liters of water to precipitate the polymer, and the resulting precipitate was filtered off and dried under vacuum to obtain a powdered polymer (polyamic acid ester B). It was 20000 when the number average molecular weight (Mn) of this polyamic acid ester B was measured by the gel permeation chromatography (standard polystyrene conversion).

<Synthesis Example 3>
(Synthesis of polyamic acid ester C)
Pyromellitic dianhydride (PMDA) 109.1g was put into a 2 liter separable flask, 13-g 2-hydroxyethyl methacrylate (HEMA) and γ-butyrolactone 400ml were added and stirred at room temperature. While adding 79.1 g of pyridine, a reaction mixture was obtained. After completion of the exothermic reaction, the mixture was allowed to cool to room temperature and left for 16 hours. Next, under ice cooling, a solution prepared by dissolving 206.3 g of dicyclohexylcarbodiimide (DCC) in 200 ml of γ-butyrolactone was added to the reaction mixture over 40 minutes with stirring. This reaction solution was added to a 5 liter separable flask in which 88.3 g of 4,4′-diaminodiphenyl ether (DADPE) was suspended in 200 ml of γ-butyrolactone with stirring in ice cooling over 60 minutes ( Reaction solution 1).

Next, stirring a solution of 23.2 g of α, ω-aminopropyl polydimethylsiloxane having a number average molecular weight of 1000 (manufactured by Chisso Corporation, Silaplane, FM3311) in 100 ml of γ-butyrolactone and 30 ml of butyl benzoate, while stirring. It added over 60 minutes (reaction liquid 2).
The reaction solution 2 was added to the reaction solution 1 over 60 minutes with stirring in ice-cooling, and further stirred at room temperature for 4 hours. Then, 240 ml of ethyl alcohol was added and stirred for 1 hour, and then 7000 ml of γ-butyrolactone. Was added. The precipitate generated in the reaction mixture was removed by filtration to obtain a reaction solution. The obtained reaction solution was added to 10 liters of ethyl alcohol to produce a precipitate consisting of a crude polymer. The produced crude polymer was separated by filtration and dissolved in 1.5 liter of tetrahydrofuran to obtain a crude polymer solution. The crude polymer solution was dropped into 28 liters of water to precipitate the polymer, and the resulting precipitate was filtered off and dried under vacuum to obtain a powdery polymer (polyamic acid ester C). It was 18000 when the number average molecular weight (Mn) of this polyamic-acid ester C was measured by the gel permeation chromatography (standard polystyrene conversion).

[Example 1]
Using the obtained polyamic acid ester A and polyamic acid ester B, a polyamic acid ester composition was prepared by the following method, and physical properties of the prepared composition were measured and evaluated. Polyamic acid ester A 100 g, Polyamic acid ester B 1 g, diphenylpropanetrione-2- (O-ethoxycarbonyl) oxime 4 g, tetraethylene glycol dimethacrylate 4 g, 1-phenyl-5-mercaptotetrazole 2 g, N-phenyldiethanolamine 4 g, N- 3 g of [3- (triethoxysilyl) propyl] phthalamic acid and 0.02 g of 2-nitroso-1-naphthol were dissolved in 150 g of NMP, and then filtered through a 1 μm Teflon filter to obtain a photosensitive resin composition (A -1) was adjusted.
[Examples 2 and 3]
A photosensitive resin composition (A-2, A-3) was prepared in the same manner as in Example 1 except that the polyamic acid ester B of Example 1 was changed to 2 g and 4 g, respectively.

[Comparative Example 1]
A photosensitive resin composition (B-1) was prepared in the same manner as in Example 1 except that the polyamic acid ester B in Example 1 was changed to 0 g.
[Comparative Example 2]
Using the polyamic acid ester C obtained above, a polyamic acid ester composition was prepared by the following method, and the physical properties of the prepared composition were measured and evaluated.
Polyamic acid ester C 100 g, diphenylpropanetrione-2- (O-ethoxycarbonyl) oxime 4 g, tetraethylene glycol dimethacrylate 4 g, 1-phenyl-5-mercaptotetrazole 2 g, N-phenyldiethanolamine 4 g, N- [3- (tri Ethoxysilyl) propyl] phthalamic acid 3 g and 2-nitroso-1-naphthol 0.02 g were dissolved in 150 g of NMP, and then filtered through a 1 μm Teflon filter to prepare a photosensitive resin composition (B-2). did.

(1) Evaluation of heat resistance When Tg of the above photosensitive resin composition (A-1, A-2, A-3, B-1, B-2) was measured by the method described above, the following table was obtained. As shown in FIG. 1, A-1, A-2, A-3, and B-1 showed good values of 300 ° C. or higher. It was 290 degreeC in B-2.
(2) Evaluation of resolution The above-mentioned photosensitive resin composition (A-1, A-2, A-3, B-1, B-2) was formed into a film for resolution measurement by the method described above. . All the resolutions of the obtained resin films were good.

(3) Evaluation of chemical resistance The above photosensitive resin composition (A-1, A-2, A-3, B-1, B-2) is coated with a chemical resistant coating film by the method described above. A film was formed. When the chemical resistance test was performed by the above-mentioned method, as shown in Table 1 below, A-1, A-2, A-3, and B-1 were acceptable. In B-2, peeling was observed in the pattern.
(4) Evaluation of metal adhesiveness The above-mentioned photosensitive resin composition (A-1, A-2, A-3, B-1, B-2) was applied to the metal adhesive coating film by the method described above. A film was formed. When adhesiveness was evaluated by the above-mentioned method, as shown in Table 1 below, good values were shown except for B-1.
As is clear from Comparative Example 1, only the (a) polyamic acid ester consisting of the A unit has high heat resistance and chemical resistance but low metal adhesion. Further, as is clear from Comparative Example 2, (b) the polyamic acid ester consisting of the A unit and the B unit alone has high metal adhesion but low heat resistance and chemical resistance.

  The polyimide resin film obtained by heat-curing the photosensitive resin composition of the present invention can be suitably used in the field of materials such as semiconductor surface protective films, interlayer insulating films, and multichip modules.

Claims (3)

(A) 100 parts by mass of a polyamic acid ester having a repeating unit represented by the following general formula (1), (b) a polyamic acid ester having two repeating units represented by the following general formula (2) 0.1 A photosensitive resin composition comprising 40 parts by mass, (c) 1 to 20 parts by mass of a photopolymerization initiator, and (d) 30 to 600 parts by mass of a solvent.

(In the formulas (1) and (2), X represents at least one tetravalent organic group having 6 to 32 carbon atoms, Y represents at least one divalent aromatic group having 4 to 30 carbon atoms, Y ′ represents at least one group selected from the group consisting of a divalent aliphatic group having 4 to 30 carbon atoms and a divalent silicon-containing group having 2 to 50 silicon atoms, and R and R ′ are each independently A monovalent group having an olefinic double bond is shown.)   The photosensitive resin composition according to claim 1, wherein the solvent (d) is a solvent containing 10 to 100% by mass of an organic solvent having a boiling point at 150 to 300 ° C.   A process of forming a coating film on the substrate by applying the photosensitive resin composition according to claim 1 to the substrate and drying, a photomask having a pattern, or directly A step of irradiating the coating film with ultraviolet light, a step of developing an unexposed portion of the coating film by developing with a developing solution to form a relief pattern on the substrate, and heating the relief pattern Forming a cured relief pattern made of a polyimide resin on the base material by a method of forming a cured relief pattern.