Negative photosensitive polyimide precursor and composition thereof

Abstract

Disclosed in the present invention is a negative photosensitive polyimide precursor having the following structure (I): wherein Z1 is a tetravalent organic group containing an aromatic group, Z2 is a divalent organic group containing an aromatic group, R1 and R2 are each independently selected from any one of an organic group represented by formula (II) and a monovalent alkyl group having 1-4 carbon atoms, and m is 2-150; the proportion of repeating units containing the structure represented by formula (II) in formula (I) is 10-100%; and R3, R4, and R5 in formula (II) are each independently selected from a hydrogen atom and an alkyl group having 1-3carbon atoms. The polyimide precursor provided by the present invention can achieve imidization at temperatures below 200ºC, and solves the problems of poor reliability, poor chemical corrosion resistance, etc. caused by a low imidization rate, from the source.

Description

A negative photosensitive polyimide precursor and a composition thereof TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic packaging, in particular to a negative photosensitive polyimide precursor and a composition thereof. BACKGROUND

[0002] Photosensitive polyimide (PSPI) materials are widely used in integrated circuit chip surface passivation and surface re-routing processes of wafer-level packaging and panel-level packaging, and are indispensable key materials in wafer-level advanced packaging processes. Traditional PSPI materials usually require a curing temperature of 350℃ or higher to obtain excellent performance. Low-temperature curing PSPI materials often have poor mechanical properties and poor chemical corrosion resistance due to insufficient imidization, which cannot meet the requirements of packaging processes. In addition, they also have poor device reliability due to poor adhesion to other materials in the packaging process, especially electroplated copper. However, high-density fan-out wafer-level packaging and other advanced packaging processes are prone to wafer warping, stress cracking, and poor compatibility with other packaging materials at high temperatures. Therefore, in order to meet the demand for low stress and low warping of wafers in advanced packaging processes, it is urgent to develop low-temperature curing PSPI, especially ultra-low-temperature curing PSPI with a curing temperature below 200℃.

[0003] Generally speaking, the introduction of photo / thermal alkali-generating agents can reduce the activation energy of polyimide precursor imidization and thus achieve low-temperature process to obtain polyimide with excellent performance, such as CN112639616A, CN112513219A, CN112639615A, CN111919172A; or control the molecular weight of the precursor, so that the molecular chain has high enough movement ability during low-temperature curing to improve the imidization rate, such as CN108475020A. For example, CN112334833A introduces a polymeric compound containing urethane and urea bond structures, CN110741318A and CN113168093A introduce a polymeric compound containing sulfite structures to obtain low-temperature curing, high imidization rate, good chemical resistance, and excellent copper surface adhesion. In addition, in order to improve the adhesion of the re-routed layer to the copper surface, various copper surface additives are generally introduced, such as CN102375336B and CN112799281A. However, the polyimides prepared by the above methods usually have no obvious effect on the improvement of their performance, or still have the problem of high thermal imidization temperature.

[0004] SUMMARY

[0005] In order to improve the imidization rate of a precursor resin photosensitive polyimide acid ester of a PSPI material in a low-temperature curing process, the present application provides a negative photosensitive polyimide precursor and a composition thereof. The present application obtains a molecular structure of a polyimide acid ester with a relatively low imidization activation energy through molecular design, thereby solving the problems of poor reliability and poor chemical corrosion resistance of low-temperature curing PSPI due to low imidization rate at the source, and further meeting the demand of ultra-low temperature curing process below 200 DEG C.

[0006] To achieve the above object, the technical scheme adopted by the present application is:

[0007] In one aspect, the present application provides a negative photosensitive polyimide precursor, which has a structure as shown in formula (I):

[0008] In formula (I), Z1 is a 4-valent organic group containing an aromatic group, Z2 is a 2-valent organic group containing an aromatic group, R1 and R2 are independently selected from any one of a 1-valent organic group having a structure as shown in formula (II) and a 1-valent alkyl group having 1-4 carbon atoms, and m is 2-150.

[0009] R1 in each repeating unit of formula (I) is the same or different group, R2 in each repeating unit of formula (I) is the same or different group, and the proportion of the repeating unit containing the 1-valent organic group having a structure as shown in formula (II) in formula (I) is 10%-100% (quantitative proportion).

[0010] In formula (II), R3, R4 and R5 are independently selected from a hydrogen atom and an alkyl group having 1-3 carbon atoms.

[0011] As a preferred embodiment, the proportion of the repeating unit containing the 1-valent organic group having a structure as shown in formula (II) in formula (I) is 30%-80%, and more preferably 50%-70%.

[0012] As a preferred embodiment, the preparation method of the negative photosensitive polyimide precursor comprises the following steps:

[0013] A tetracarboxylic dianhydride containing a Z1 group, an alcohol containing an R1 group and an alcohol containing an R2 group are reacted to prepare a partially esterified tetracarboxylic acid, which is then subjected to amide polycondensation with a diamine containing a Z2 group.

[0014] The tetracarboxylic dianhydride containing the Z1 group is not particularly limited, and specifically, 4,4'-oxydiphthalic anhydride, pyromellitic anhydride, diphenyl ether-3,3',4,4'-tetracarboxylic dianhydride, benzophenone-3,3',4,4'-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic dianhydride, diphenyl sulfone-3,3',4,4'-tetracarboxylic dianhydride, diphenyl methane-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 can be listed, and preferably, 4,4'-oxydiphthalic anhydride, pyromellitic anhydride, diphenyl ether-3,3',4,4'-tetracarboxylic dianhydride, benzophenone-3,3',4,4'-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic dianhydride, and the like can be listed, and more preferably, pyromellitic anhydride, diphenyl ether-3,3',4,4'-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic dianhydride, and the like can be listed, and the above can be used alone or in any mixture.

[0015] The tetracarboxylic dianhydride and the alcohol are preferably reacted in the presence of a basic catalyst such as pyridine at 20 to 50°C for 4 to 10 hours in a suitable solvent to obtain a partially esterified tetracarboxylic acid.

[0016] As the solvent in the above reaction, a solvent capable of completely dissolving the raw materials and / or the product is preferred, and a solvent capable of completely dissolving the photosensitive polyimide precursor is more preferred. As such a solvent, specifically, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, tetramethyl urea, ketones, esters, lactones, ethers, halogenated hydrocarbons, hydrocarbons, and the like can be listed, and the above can be used alone or in any mixture.

[0017] The solution containing the partially esterified tetracarboxylic acid obtained in the above reaction is preferably added to a dehydration condensing agent under ice-bath conditions, and then a diamine containing the Y group or a solution thereof is added to obtain the target negative photosensitive polyimide precursor by amide polycondensation.

[0018] As the dehydration condensing agent in the above reaction, specifically, dicyclohexyl carbodiimide, 1-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline, 1,1-carbonyldioxy-di-1,2,3-benzotriazole, N,N'-disuccinimidyl carbonate, and the like can be listed, and the above can be used alone or in any mixture.

[0019] As the diamine containing the Z2 group, there is no particular limitation, and specific examples include p-phenylenediamine, m-phenylenediamine, 4,4'-oxydianiline, 3,4'-oxydianiline, 3,3'-oxydianiline, 4,4'-thiodianiline, 3,4'-thiodianiline, 3,3'-thiodianiline, 4,4'-sulfonophenylamine, 3,4'-sulfonophenylamine, 3,3'-sulfonophenylamine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 4,4'-benzophenonediamine, 3,4'-benzophenonediamine, 3,3'-benzophenonediamine, 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 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, 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, 3,3'-dimethyl-4,4'-diaminodiphenyl sulfone, 9,9-bis(4-aminophenyl)fluorene, and the like, which can be used alone or in any mixture.

[0020] In another aspect, the present application provides a negative type photosensitive polyimide precursor composition, comprising:

[0021] 100 parts by mass of the above-mentioned negative type photosensitive polyimide precursor;

[0022] 5 to 20 parts by mass of a radical polymerizable compound;

[0023] 0.5 to 5 parts by mass of a photopolymerization initiator;

[0024] 0.5 to 5 parts by mass of a silane coupling agent;

[0025] 0.01 to 1 part by mass of a polymerization inhibitor;

[0026] 1 to 5 parts by mass of a bridging agent;

[0027] 0.5 to 3 parts by mass of an antioxidant;

[0028] 0.1 to 2 parts by mass of an adhesion aid.

[0029] In some embodiments, the amount of the radical polymerizable compound is 5 parts, 7 parts, 10 parts, 12 parts, 15 parts, 17 parts, 20 parts, or any amount therebetween, based on 100 parts by mass of the negative photosensitive polyimide precursor.

[0030] In some embodiments, the amount of the photopolymerization initiator is 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, or any amount therebetween, based on 100 parts by mass of the negative photosensitive polyimide precursor.

[0031] In some embodiments, the amount of the silane coupling agent is 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, or any amount therebetween, based on 100 parts by mass of the negative photosensitive polyimide precursor.

[0032] In some embodiments, the amount of the polymerization inhibitor is 0.01 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, or any amount therebetween, based on 100 parts by mass of the negative photosensitive polyimide precursor.

[0033] In some embodiments, the amount of the bridging agent is 1 part, 2 parts, 3 parts, 4 parts, 5 parts, or any amount therebetween, based on 100 parts by mass of the negative photosensitive polyimide precursor.

[0034] In some embodiments, the amount of the antioxidant is 0.5 parts, 1 part, 2 parts, 3 parts, or any amount therebetween, based on 100 parts by mass of the negative photosensitive polyimide precursor.

[0035] In some embodiments, the amount of the adhesion aid is 0.1 parts, 0.5 parts, 1 part, 1.5 parts, 2 parts, or any amount therebetween, based on 100 parts by mass of the negative photosensitive polyimide precursor.

[0036] In the technical solution of the present application, the radical polymerizable compound can be exemplified by trimethylolpropane diacrylate, trimethylolpropane triacrylate, trimethylolpropane dimethacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, styrene, divinylbenzene, 4-vinyltoluene, 4-vinylpyridine, N-vinylpyrrolidone, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 1,3-acryloyloxy-2-hydroxypropane, 1,3-methacryloyloxy-2-hydroxypropane, methylenebisacrylamide, N,N-dimethylacrylamide, N-hydroxymethylacrylamide, triallylisocyanurate, and the like, which can be used alone or in any combination.

[0037] As a preferred embodiment, the photopolymerization initiator is selected from any one or more of oxime ester compounds, benzophenone, N,N'-tetramethyl-4,4'-diaminobenzophenone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholin-1-propanone, alkylanthraquinone, benzoin alkyl ether, benzoin, alkylbenzoin, and benzil dimethyl ketal, further preferably oxime ester compounds.

[0038] In the technical solution of the present application, the silane coupling agent is not particularly limited, and is preferably any one or more of silane coupling agents containing urea bonds (-NH-CO-NH-);

[0039] In particular, the silane coupling agent is selected from any one or more of ureidopropyltriethoxysilane, gamma-aminopropyl dimethoxysilane, N-(beta-aminoethyl)-gamma- aminopropylmethyldimethoxysilane, gamma-glycidoxypropylmethyldimethoxysilane, gamma- mercaptopropylmethyldimethoxysilane, 3-methacryloxypropyldimethoxymethylsilane, 3- methacryloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinylpropylsilane, diethoxy- 3-glycidoxypropylmethylsilane, N-(3-diethoxymethylsilylpropyl)succinimide, N-[3- (triethoxysilyl)propyl]phthalamic acid, benzophenone-3,3'-bis(N-[3- triethoxysilyl]propylamide)-4,4'-dicarboxylic acid, benzene-1,4-bis(N-[3- triethoxysilyl]propylamide)-2,5-dicarboxylic acid, 3-(triethoxysilyl)propyl succinic anhydride, and N-phenylaminopropyltrimethoxysilane, preferably ureidopropyltriethoxysilane.

[0040] In the technical solution of the present application, the polymerization inhibitor is not particularly limited, and is preferably any one or more of a phenolic radical polymerization inhibitor;

[0041] In particular, the polymerization inhibitor is selected from any one or more of hydroquinone, N-nitrosodiphenylamine, p-tert-butylcatechol, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol ether diamine tetraacetic acid, 2,6-di-tert-butyl-p-cresol, 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, and N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt, preferably 2-nitroso-1-naphthol.

[0042] As a preferred embodiment, the bridging agent is an amino resin;

[0043] In the technical solution of the present application, the bridging agent is selected from any one or more of diol urea resin, hydroxy ethylene urea resin, and melamine resin, and is particularly preferably an alkoxymethylated melamine compound, such as hexamethoxymethyl melamine.

[0044] As a preferable embodiment, the antioxidant is a hindered phenol antioxidant, preferably a compound having a hindered structure at the ortho carbon atom of the phenolic hydroxyl group, and specifically, one or more of 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, bis(3,5-di-tert-butyl-4-hydroxy-phenylpropionyl)hydrazine, 2,2-oxamidyl-bis[ethyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)]propionate, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, N,N'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxyphenylpropionamide), 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid] ester, and the like, and particularly preferably one or more of 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, and the like, and the above-listed compounds can be used alone or in any mixture.

[0045] As a preferable embodiment, the adhesion aid is an azole compound;

[0046] Preferably, the adhesion aid is selected from 1H-triazole, 5-methyl-1H-triazole, 5-ethyl-1H-triazole, 4,5-dimethyl-1H-triazole, 5-phenyl-1H-triazole, phenyltriazole, 1,5-dimethyltriazole, 4,5-diethyl-1H-triazole, 1H-benzotriazole, hydroxyphenylbenzotriazole, tolyltriazole, 5-methyl-1H-benzotriazole, 4-methyl-1H-benzotriazole, 1H-tetrazole, 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole, 1-methyl-1H-tetrazole, and the like. Particularly preferably, one or more of 1H-benzotriazole, 5-methyl-1H-benzotriazole, and 4-methyl-1H-benzotriazole; in the technical solution of the present application, the adhesion aid can improve the adhesion strength at the interface with the metal substrate.

[0047] As a preferable embodiment, an organic solvent is further included;

[0048] Preferably, the organic solvent is selected from any one or more of esters, ethers, ketones, aromatic hydrocarbons, sulfoxides and amides;

[0049] Preferably, the esters are selected from any one or more of ethyl acetate, n-butyl acetate, isobutyl acetate, pentyl formate, isoamyl acetate, butyl propionate, isopropyl butyrate, ethyl butyrate, butyl butyrate, methyl lactate, ethyl lactate, γ-butyrolactone, ε-caprolactone, δ-valerolactone, alkyl alkoxyacetate, alkyl 3-alkoxypropionate, alkyl 2-alkoxypropionate, methyl 2-alkoxy-2-methylpropionate, ethyl 2-alkoxy-2-methylpropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl 2-oxobutyrate and ethyl 2-oxobutyrate;

[0050] Preferably, the ethers are selected from any one or more of diethylene glycol dimethyl ether, tetrahydrofuran, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate and propylene glycol monopropyl ether acetate;

[0051] Preferably, the ketones are selected from any one or more of methyl ethyl ketone, cyclohexanone, cyclopentanone, 2-heptanone and 3-heptanone;

[0052] Preferably, the aromatic hydrocarbons are selected from any one or more of toluene, xylene, anisole and limonene;

[0053] Preferably, the amides are selected from any one or more of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylacetamide and N,N-dimethylformamide.

[0054] Preferably, the organic solvent is selected from any one or more of N-methyl-2-pyrrolidone, γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether acetate, N,N-dimethylformamide and N,N-dimethylacetamide, in consideration of solubility of each component and resin film coatability;

[0055] In the technical solution of the present application, the amount of the organic solvent is determined so that the negative photosensitive polyimide precursor resin composition can obtain a uniform glue solution; in some specific embodiments, in order to simultaneously meet the glue coating thickness requirement, the amount of the organic solvent is determined so that the viscosity of the negative photosensitive polyimide precursor resin composition is 20-80 poise.

[0056] In another aspect, the present application provides a negative photosensitive polyimide resin composition obtained by thermal imidization of the above-mentioned negative photosensitive polyimide precursor resin composition, wherein the thermal imidization is preferably performed at a temperature of 150 to 400°C.

[0057] In the technical solution of the present application, the above-mentioned negative photosensitive polyimide precursor resin composition can be cured by thermal imidization to obtain a cured negative photosensitive polyimide resin composition, and can also be prepared into a patterned negative photosensitive polyimide resin composition by a mask with a specific pattern.

[0058] The method for preparing the patterned negative photosensitive polyimide resin composition comprises the following steps:

[0059] (1) coating the above-mentioned negative photosensitive polyimide precursor resin composition on a substrate to form a negative photosensitive polyimide precursor resin layer on the substrate;

[0060] (2) exposing the negative photosensitive polyimide precursor resin layer on the substrate;

[0061] (3) developing the exposed negative photosensitive polyimide precursor resin layer to form a pattern;

[0062] (4) heating the pattern to form a cured pattern.

[0063] In step (1), the coating method is not particularly limited, and methods such as spin coating, blade coating, screen printing, spray coating, etc. can be used, and then the negative photosensitive polyimide precursor resin layer is formed by drying as needed; the drying method can be heating drying using an oven or a hot plate, vacuum drying, etc.; and the substrate can be a metal substrate such as Cu, a glass substrate, a semiconductor substrate, a metal oxide insulator (TiO2, SiO2, etc.), a silicon nitride substrate, etc.

[0064] Preferably, the drying is performed under conditions in which the polyamic acid ester in the negative photosensitive polyimide precursor resin composition does not undergo imidization; specifically, the drying is performed at 70 to 130°C for 1 to 10 minutes.

[0065] In step (2), the negative photosensitive polyimide precursor resin layer is exposed through a mask with a specific pattern; the exposure device used can be a parallel exposure machine, a projection exposure machine, a step exposure machine, a scanning exposure machine, etc.; and the light source used can be ultraviolet light, visible light, or radioactive rays, etc.

[0066] In step (3), the unexposed part of the negative photosensitive polyimide precursor resin layer after exposure is removed using a developing solution to form a pattern; the developing agent used is a good solvent for the negative photosensitive polyimide precursor resin layer or a mixed solvent of a good solvent and a poor solvent.

[0067] As the good solvent, N-methyl-2-pyrrolidone, N-acetyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, γ-butyrolactone, α-acetyl-γ-butyrolactone, cyclopentanone, cyclohexanone, and the like can be exemplified, and the above exemplifications can be used singly or in any mixture;

[0068] As the poor solvent, toluene, xylene, methanol, ethanol, isopropanol, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, water, and the like can be exemplified, and the above exemplifications can be used singly or in any mixture.

[0069] When the mixed solvent of the good solvent and the poor solvent of the negative photosensitive polyimide precursor resin layer is selected as the developing solution, the ratio of the good solvent to the poor solvent is determined according to the solubility of the polymer in the resin layer.

[0070] As the method of the developing solution treatment, there is no particular limitation, and the known developing methods, such as a rotary spray method, an agitation method, an immersion method, and the like, can be used.

[0071] After the developing solution treatment, further rinsing can be performed, and the rinsing solution is preferably a solvent different from the developing solution used.

[0072] In the step (4), the polyamic acid ester is imidized by heating the pattern obtained by the above developing to obtain the corresponding cured polyimide.

[0073] The temperature of the heating treatment is 150 to 400°C, and within this reaction temperature, the crosslinking reaction or the dehydration ring-closing reaction can be sufficiently performed.

[0074] In another aspect, the present application provides the use of the above-mentioned negative photosensitive polyimide precursor or the above-mentioned negative photosensitive polyimide precursor resin composition in electronic packaging.

[0075] The negative photosensitive polyimide precursor resin composition in the present application can be applied to the preparation of semiconductor devices by the above-mentioned method, and can also be used for the interlayer insulation of multilayer circuits, the covering coating of flexible copper-clad plates, and the like.

[0076] The above technical solution has the following advantages or beneficial effects:

[0077] In order to improve the imidization rate of the polyimide precursor in the low-temperature curing process, the application provides a special polyimide precursor molecule polyamic acid ester. The application introduces a tert-butyl group into the alcohol compound of the esterification of the polyimide precursor molecule, realizes the imidization temperature below 200 DEG C, and solves the problems of poor reliability and poor chemical corrosion resistance of the polyimide caused by the low imidization rate of the polyimide precursor molecule from the source, and meets the ultra-low temperature curing process demand of the semiconductor advanced packaging below 200 DEG C. Meanwhile, the application limits the number of unsaturated groups on the side chain of the polyimide precursor molecule within a certain range, reduces the residual components except the polyimide main body in the low-temperature curing process, and can further improve the chemical corrosion resistance and device reliability. DETAILED DESCRIPTION

[0078] The following examples are only a part of the examples of the application, not all the examples. Therefore, the detailed description of the examples of the application provided below is not intended to limit the scope of the claimed application, but only represents selected embodiments of the application. Based on the examples of the application, all other examples obtained by those skilled in the art without creative labor belong to the protection scope of the application.

[0079] In the application, all the equipment and raw materials, etc. can be purchased from the market or commonly used in the industry, unless otherwise specified. The methods in the following examples are all conventional methods in the art, unless otherwise specified.

[0080] The room temperature in the following examples is 20-30 DEG C.

[0081]

Synthesis Example

[0082] Synthesis Example 1: Polyimide precursor P1

[0083] Disperse 103 g of 4,4'-oxydiphthalic anhydride (ODPA) in solvent gamma-butyrolactone (GBL), add 106 g of hydroxyl tert-butyl methacrylate at one time, and then drop 3 g of pyridine, and react for 6 h at 50 degrees Celsius; after being reduced to room temperature, dissolve 137 g of dicyclohexyl carbodiimide (DCC) in GBL, slowly drop into the reaction system, and stir for 2 h; dissolve 67 g of 4,4'-diamino diphenyl ether (ODA) in GBL in a nitrogen atmosphere, slowly drop into the reaction system, and stir for 9 h after the drop is completed; if stirring is difficult during the entire reaction period, the reaction system can be appropriately diluted by adding solvent; after the reaction is completed, add 5 mL of ethanol quenching agent and react for 2 h; press filter the quenched reaction liquid, immediately add methanol to the filtrate to precipitate blocky solids, dissolve the blocky solids in GBL after being refrigerated for 12 h, drop into water, and filter and dry to obtain the corresponding polyimide precursor P1. The structure of the main repeating unit in the polyimide precursor P1 prepared in this synthesis example is shown below, and the proportion of the side chain substituent corresponding to the hydroxyl tert-butyl methacrylate in the structure is 100%; the polymer molecular weight is M w 28200, and the PDI is 1.93.

[0084] Synthesis Example 2: Polyimide Precursor P2

[0085] Use 53 g of hydroxyl tert-butyl methacrylate and 25 g of tert-butyl alcohol instead of the 106 g of hydroxyl tert-butyl methacrylate component in the synthesis example 1, and the remaining components and operation procedures remain the same as those in the synthesis example 1 to obtain the polyimide precursor P2. In this synthesis example, the number proportion of the substituent corresponding to the hydroxyl tert-butyl methacrylate to the substituent corresponding to the tert-butyl alcohol in the polyimide precursor side chain substituent is 5:5; the polymer molecular weight is M w 27500, and the PDI is 1.88.

[0086] Synthesis Example 3: Polyimide Precursor P3

[0087] Use 74 g of hydroxyl tert-butyl methacrylate and 15 g of tert-butyl alcohol instead of the 106 g of hydroxyl tert-butyl methacrylate component in the synthesis example 1, and the remaining components and operation procedures remain the same as those in the synthesis example 1 to obtain the polyimide precursor P3. In this synthesis example, the number proportion of the substituent corresponding to the hydroxyl tert-butyl methacrylate to the substituent corresponding to the tert-butyl alcohol in the polyimide precursor side chain substituent is 7:3; the polymer molecular weight is M w 27870, and the PDI is 1.91.

[0088] Synthesis Example 4: Polyimide Precursor P4

[0089] Synthesis Example 4 Polyimide Precursor P4 w Mn was 28030, and PDI was 1.95.

[0090] Synthesis Example 5 Polyimide Precursor P5

[0091] Synthesis Example 4 Polyimide Precursor P4 w Mn was 27410, and PDI was 1.80.

[0092] Synthesis Example 6 Polyimide Precursor P6

[0093] Synthesis Example 4 Polyimide Precursor P4 w Mn was 27230, and PDI was 1.75.

[0094] Synthesis Example 7 Polyimide Precursor P7

[0095] Synthesis Example 4 Polyimide Precursor P4 w Mn was 26890, and PDI was 1.78.

[0096] Synthesis Example 8 Polyimide Precursor P8

[0097] 87g of hydroxyethyl methacrylate was used to replace 106g of hydroxy tert-butyl methacrylate in Synthesis Example 1. The remaining components and operation procedures were the same as those in Synthesis Example 1 to obtain polyimide precursor P8. The structural formula of the main repeating unit in the polyimide precursor P8 prepared in this synthesis example is shown below. The proportion of the side chain substituents in the structural formula, i.e., the substituents corresponding to hydroxyethyl methacrylate, is 100%. The molecular weight of the polymer obtained by APC testing is: M w It is 27250 and the PDI is 1.87.

[0098] Synthesis Example 9 Polyimide Precursor P9

[0099] 43.5 g of hydroxyethyl methacrylate and 15.4 g of ethanol were used to replace 106 g of hydroxy tert-butyl methacrylate in Synthesis Example 1. The remaining components and operation procedures were the same as those in Synthesis Example 1 to obtain polyimide precursor P9. In this synthesis example, the ratio of the number of substituents corresponding to hydroxyethyl methacrylate and the number of substituents corresponding to ethanol in the side chain substituents of the polyimide precursor was 5:5; the molecular weight of the polymer obtained by APC test was: M w It is 26980 and the PDI is 1.93.

[0100] [Example]

[0101] Example 1

[0102] Under a constant temperature and humidity environment (24°C, 50% RH), 20 g of polyimide precursor P1, 30 g of N-methylpyrrolidone (NMP) solvent, 2.0 g of free radical polymerizable compound triallyl isocyanurate (PC-1), 0.4 g of hexamethoxymethyl melamine (TC-1), 0.8 g of photopolymerization initiator BASF IRGACURE OXE-01, 0.4 g of silane coupling agent ureapropyl triethoxysilane (Si-1), 0.04 g of polymerization inhibitor 2-nitroso-1-naphthol, and 0.2 g of dimethicone were added to a 100 mL brown plastic bottle in sequence. 1,3,5-Tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanuric acid (AO-1) and 0.04 g of benzotriazole (MA-1) were shaken and dissolved on a shaker for 24 hours, and then NMP was added to adjust the viscosity to about 30 poise. After secondary filtration, a negative photosensitive polyimide precursor resin composition was prepared.

[0103] Preparation of cured films with photolithographic patterns:

[0104] A negative photosensitive polyimide precursor resin composition was spin-coated onto an 8-inch silicon wafer and pre-baked on a hot plate for 240 seconds at 100°C to form a coating film approximately 10 μm thick. This coating film was then irradiated with 400 mJ / cm using an i-line projection stepper using a mask with a test pattern. 2 The coating film was then spray-developed using cyclopentanone as a developer in a developer and rinsed with propylene glycol methyl ether acetate to obtain a photoresist pattern. Heat treatment was performed for 2 hours in a temperature-programmed curing oven under a nitrogen atmosphere under the curing conditions listed in Table 2 to obtain a cured film with a thickness of approximately 10 μm and a photoresist pattern.

[0105] Example 2

[0106] 20 g of polyimide precursor P1 in Example 1 was replaced by 20 g of polyimide precursor P2, and the remaining components and operation procedures remained the same as those in Example 1.

[0107] Example 3

[0108] 20 g of polyimide precursor P1 in Example 1 was replaced by 20 g of polyimide precursor P3, and the remaining components and operation procedures remained the same as those in Example 1.

[0109] Example 4

[0110] 20 g of polyimide precursor P1 in Example 1 was replaced by 20 g of polyimide precursor P4, and the remaining components and operation procedures remained the same as those in Example 1.

[0111] Example 5

[0112] 20 g of polyimide precursor P1 in Example 1 was replaced by 20 g of polyimide precursor P5, and the remaining components and operation procedures remained the same as those in Example 1.

[0113] Example 6

[0114] 20 g of polyimide precursor P1 in Example 1 was replaced by 20 g of polyimide precursor P6, and the remaining components and operation procedures remained the same as those in Example 1.

[0115] Example 7

[0116] 20 g of polyimide precursor P1 in Example 1 was replaced by 20 g of polyimide precursor P7, and the remaining components and operation procedures remained the same as those in Example 1.

[0117] Example 8

[0118] Replace 20 g of polyimide precursor P1 in Example 1 with a mixture of 10 g of polyimide precursor P1 and 10 g of polyimide precursor P6, and keep the rest of the components and the operation procedure consistent with Example 1.

[0119] Example 9

[0120] Replace 20 g of polyimide precursor P1 in Example 1 with a mixture of 10 g of polyimide precursor P1 and 10 g of polyimide precursor P7, and keep the rest of the components and the operation procedure consistent with Example 1.

[0121] Example 10

[0122] Increase the amount of TC-1 in Example 1 from 0.4 g to 0.8 g, and change the curing process to 180 °C / 2 h, and keep the rest of the components and the operation procedure consistent with Example 1.

[0123] Example 11

[0124] Increase the amount of TC-1 in Example 2 from 0.4 g to 0.8 g, and change the curing process to 180 °C / 2 h, and keep the rest of the components and the operation procedure consistent with Example 2.

[0125] Example 12

[0126] Increase the amount of TC-1 in Example 3 from 0.4 g to 0.8 g, and change the curing process to 180 °C / 2 h, and keep the rest of the components and the operation procedure consistent with Example 3.

[0127] Example 13

[0128] Increase the amount of TC-1 in Example 4 from 0.4 g to 0.8 g, and change the curing process to 180 °C / 2 h, and keep the rest of the components and the operation procedure consistent with Example 4.

[0129] Comparative Example 1

[0130] Replace 20 g of polyimide precursor P1 in Example 1 with 20 g of polyimide precursor P8, and keep the rest of the components and the operation procedure consistent with Example 1.

[0131] Comparative Example 2

[0132] Replace 20 g of polyimide precursor P1 in Example 1 with 20 g of polyimide precursor P9, and keep the rest of the components and the operation procedure consistent with Example 1.

[0133] Comparative Example 3

[0134] Replace 20 g of polyimide precursor P1 in Example 10 with 20 g of polyimide precursor P9, and keep the rest of the components and the operation procedure consistent with Example 10.

[0135] Effect test

[0136] 1. Weight average molecular weight test:

[0137] The weight average molecular weight Mw of the polymer involved in the present application w and the polymer dispersity index (PDI) are obtained by ultra-high performance polymer chromatography analysis instrument.

[0138] 2. Preparation and evaluation method of lithographic pattern:

[0139] The cross-section analysis of the cured film obtained above is carried out by focused ion beam electron microscope to evaluate the lithographic precision and cross-sectional profile, and then the lithographic performance of the negative photosensitive resin composition is evaluated: the lithographic line precision less than 10 μm is evaluated as 'excellent', the lithographic line precision between 10-20 μm is evaluated as 'good', the lithographic line precision between 20-50 μm is evaluated as 'fair', and the lithographic line precision greater than 50 μm is evaluated as 'poor'.

[0140] 3. Chemical resistance test of cured film:

[0141] The cured film prepared above is immersed in 1% hydrofluoric acid aqueous solution for 10 min, then peeled off to obtain an intact cured film, which is dried in an oven at 150℃, then immersed in a dimethyl sulfoxide solution containing 2.38% tetramethylammonium hydroxide at 50℃ for 60 min. The chemical resistance of the cured film is evaluated according to the weight loss before and after the chemical resistance treatment: the weight loss less than 5% is evaluated as 'excellent', the weight loss between 5%-15% is evaluated as 'good', the weight loss between 15%-25% is evaluated as 'fair', and the weight loss greater than 25% is evaluated as 'poor'.

[0142] 4. Adhesion test of cured film on copper surface:

[0143] The cured film is prepared on the copper substrate by using a mask with a specific pattern and the method 3 above, and placed in a high temperature and high humidity accelerated aging test chamber, the test conditions are 130℃, 85% RH for 264h. After the test, the adhesion of the cured film on the copper surface is evaluated by the cross hatch method: the grid 100% without falling off is evaluated as 'excellent', the grid falling off rate within 5% is evaluated as 'good', the grid falling off rate within 5%-15% is evaluated as 'fair', and the grid falling off rate greater than 15% is evaluated as 'poor'.

[0144] The weight of each component of the negative photosensitive polyimide precursor resin composition in the above examples and comparative examples, the curing conditions, and the related performance test data of the cured film prepared are shown in Tables 1-2.

[0145] Table 1

[0146] Table 2

[0147] As can be seen from Tables 1-2, the negative photosensitive polyimide precursor prepared in the present application can be heat imidized at a temperature below 200°C, i.e. a higher imidization rate can be obtained. Moreover, the performance of the cured film prepared at a heat imidization temperature of 180°C does not decrease significantly compared with that prepared at a heat imidization temperature of 200°C. Among them, the example with a higher proportion of unsaturated groups on the side chain of the polyimide precursor has the best comprehensive performance after imidization. The example using 4,4'-oxydiphthalic anhydride (ODPA) and 4,4'-oxydianiline (ODA) as dianhydride and diamine has the best performance.

[0148] The above only describes the preferred embodiments of the present application, and it should be pointed out that for ordinary skilled in the art, several improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A negative photosensitive polyimide precursor, characterized in that The negative photosensitive polyimide precursor has a structure as shown in formula (I): In formula (I), Z1 is a 4-valent organic group containing an aromatic group, Z2 is a 2-valent organic group containing an aromatic group, R1 and R2 are each independently selected from any one of a 1-valent organic group represented by the structure of formula (II) and a 1-valent alkyl group having 1 to 4 carbon atoms, and m is 2 to 150. R1in each repeating unit of formula (I) is the same or different group, R2in each repeating unit of formula (I) is the same or different group, and the proportion of the repeating unit containing the monovalent organic group represented by formula (II) in formula (I) is 10% to 100%; In formula (II), R3, R4 and R5 are each independently selected from a hydrogen atom and an alkyl group having 1 to 3 carbon atoms.

2. Use of the negative type photosensitive polyimide precursor of claim 1 in electronic packaging.

3. A negative photosensitive polyimide precursor resin composition, characterized in that comprises: 100 parts by mass of the negative type photosensitive polyimide precursor of claim 1; 5 to 20 parts by mass of a radical polymerizable compound; 0.5 to 5 parts by mass of a photopolymerization initiator; 0.5 to 5 parts by mass of a silane coupling agent; 0.01 to 1 part by mass of a polymerization inhibitor; 1 to 5 parts by mass of a bridging agent; 0.5 to 3 parts by mass of an antioxidant; 0.1 to 2 parts by mass of an adhesion aid.

4. The negative photosensitive polyimide precursor resin composition according to claim 3, characterized by The photopolymerization initiator is selected from any one or more of an oxime ester compound, a benzophenone, N,N'-tetramethyl-4,4'-diaminobenzophenone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropanone, an alkyl anthraquinone, a benzoin alkyl ether, benzoin, an alkylbenzoin, and a benzil dimethyl ketal.

5. The negative photosensitive polyimide precursor resin composition according to claim 3, wherein The bridging agent is an amino resin.

6. The negative photosensitive polyimide precursor resin composition according to claim 4, wherein The bridging agent is selected from any one or more of a diol urea resin, a hydroxy ethylene urea resin, and a melamine resin.

7. The negative photosensitive polyimide precursor resin composition according to claim 3, wherein The antioxidant is a hindered phenol-based antioxidant.

8. The negative photosensitive polyimide precursor resin composition according to claim 7, wherein The antioxidant is a compound having a hindered structure at the ortho carbon atom of a phenolic hydroxyl group.

9. The negative photosensitive polyimide precursor resin composition according to claim 3, wherein The adhesion aid is an azole compound.

10. The negative photosensitive polyimide precursor resin composition according to claim 9, wherein The adhesion aid is selected from any one or more of 1H-triazole, 5-methyl-1H-triazole, 5-ethyl-1H-triazole, 4,5-dimethyl-1H-triazole, 5-phenyl-1H-triazole, phenyltriazole, 1,5-dimethyltriazole, 4,5-diethyl-1H-triazole, 1H-benzotriazole, hydroxyphenylbenzotriazole, tolyltriazole, 5-methyl-1H-benzotriazole, 4-methyl-1H-benzotriazole, 1H-tetrazole, 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole, and 1-methyl-1H-tetrazole.

11. The negative photosensitive polyimide precursor resin composition according to claim 3, characterized by An organic solvent is further included.

12. The negative photosensitive polyimide precursor resin composition according to claim 11, wherein The organic solvent is selected from any one or more of an ester, an ether, a ketone, an aromatic hydrocarbon, a sulfoxide, and an amide.

13. Use of the negative type photosensitive polyimide precursor resin composition of claim 3 in electronic packaging.

14. A negative photosensitive polyimide resin composition, characterized in that: by thermal imidization of the negative type photosensitive polyimide precursor resin composition of claim 3.

15. The negative photosensitive polyimide resin composition according to claim 14, wherein The thermal imidization is performed at a temperature of 150 to 400°C.

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