A negative photosensitive polyimide precursor resin composition and use thereof

Abstract

The present application relates to a kind of negative photosensitive type polyimide precursor resin composition.The present application also provides a kind of photosensitive type latent thermal induced base generator and its preparation method.Further, the present application also provides a kind of polyamic acid ester resin capped with active photo-crosslinking group phenolic hydroxyl compound, and the preparation method of polyamic acid ester resin.Compared with prior art, the negative photosensitive type polyimide precursor resin composition prepared by the present application has good low-temperature curing, photo pattern performance, and the low-temperature curing film has good thermal stability, good peeling performance with copper foil, and can be applied to advanced electronic packaging field.

Description

TECHNICAL FIELD

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

[0002] Photosensitive polyimide (PSPI) materials have excellent thermal stability, mechanical and dielectric properties, and are widely used in advanced semiconductor packaging fields, such as stress buffer layers, passivation layers, insulating dielectric layers in multilayer substrate manufacturing. However, the traditional PSPI material needs to be cured at a high temperature of 350℃. Such a high curing temperature is easy to cause the silicon-based wafer to warp and deform, greatly limiting the wide application of the system in the wafer-level packaging field. Therefore, it is particularly urgent to develop a PSPI system that can be cured at a lower temperature (≤230℃) to meet the needs of wafer-level packaging.

[0003] In many studies of negative PSPI materials, alkaline catalysts (such as aromatic heterocyclic, photo-induced or thermal-induced alkali generators) are used to effectively reduce the reaction energy barrier, so that the precursor of PSPI can be cured at low temperature. For example, CN116520640A realizes low-temperature curing of polyamic acid ester precursor by introducing DBU organic salt. However, these alkaline additives will escape from the film during imidization, resulting in defects in the film and affecting the overall performance and quality of the film. Therefore, it is very important to develop an alkaline low-temperature curing promoter that can realize low-temperature curing and not volatilize in subsequent processes. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a negative photosensitive polyimide precursor resin composition and application thereof, which adds a photosensitive latent thermal-induced alkali generator in the composition. In the process of photo-induced radical polymerization, the additive participates in the crosslinking network of methacrylate, which can avoid the problem of volatilization.

[0005] The first aspect of the present application is a negative photosensitive polyimide precursor resin composition, which comprises:

[0006] The first aspect of the present application is a negative photosensitive polyimide precursor resin composition, which comprises:

[0007] 25-35 parts by weight of polyamic acid ester;

[0008] 45-60 parts by weight of organic solvent;

[0009] 5-20 parts by weight of photo-crosslinking agent;

[0010] 1-10 parts by weight of photo-initiator;

[0011] 2-5 parts by weight of photosensitive latent thermal-induced alkali generator;

[0012] 0.005-5 parts by weight of a thermal polymerization inhibitor;

[0013] 0.01-2 parts by weight of an antioxidant;

[0014] wherein the structure general formula of the photosensitive latent thermal base generator is:

[0015]

[0016] In the formula, n represents the number of methylene groups, n is an integer from 2 to 10, R1 is selected from any one of an ester group or an amide group, R2, R3, R4, R5, R6, and R7 are each independently selected from any one of a hydrogen atom, a methyl group, an ethyl group, or a propyl group.

[0017] The present application realizes low-temperature curing of a high-temperature curing type PSPI system by introducing a photosensitive latent thermal base generator, effectively reduces the curing temperature of the PSPI system, and compared with traditional alkaline additives, the photosensitive latent thermal base generator of the present application has the following advantages.

[0018] Excellent light curing participation: the molecule contains a photosensitive acrylate group, which can actively participate in the cross-linked network of free radical polymerization in the light curing stage, which not only gives the composition photosensitivity, but also completely avoids the fatal problem that the traditional alkaline additive is easy to escape from the film in the subsequent post-baking process.

[0019] High-efficiency low-temperature catalytic ability: the complex organic salt (ionic bond) formed by the imidazole nitrogen heterocycle and acrylic acid in its structure remains inert at room temperature to ensure stability; upon heating dissociation, it can simultaneously release the alkaline imidazole nitrogen heterocycle with low-temperature catalytic activity and the high-polarity carboxyl group. This unique "thermal switch" mechanism precisely realizes efficient imidization catalysis of the polyimide precursor (polyamide acid ester) at low temperature (≤230℃).

[0020] Strong metal adhesion enhancement: the imidazole ring nitrogen atom and the carboxyl group produced by dissociation can have strong coordination with the surface of the copper foil, significantly improving the interfacial adhesion performance (peeling strength) between the low-temperature cured film and the copper foil.

[0021] As a preferred solution, the preparation method of the photosensitive latent thermal base generator comprises the following steps:

[0022] A1:

[0023] reacting to obtain an esterification product;

[0024] or reacting to obtain an amide product;

[0025] A2:

[0026] reacting the esterified product or the amidated product with to obtain the photosensitive latent thermal base-generating agent;

[0027] wherein the reaction temperature of A1 is -15 to 0℃, the reaction time is 5 to 24h, and the reaction solvent includes at least one of N-methylpyrrolidone, N,N-dimethylformamide or N,N-dimethylacetamide; the reaction temperature of A2 is -15 to 15℃, the reaction time is 5 to 24h, and the reaction solvent includes at least one of N-methylpyrrolidone, N,N-dimethylformamide or N,N-dimethylacetamide.

[0028] More preferably, selected from

[0029] As a preferred solution, the polyamic acid ester has a general structure of:

[0030]

[0031] wherein m represents a polymerization degree, m is an integer of 10 to 100, X is a tetravalent organic group containing an aromatic group, Y is a divalent organic group containing an aromatic group, Z is a monovalent aromatic organic group having at least one selected from a maleimide group, a vinyl group, R8 and R9 are independently selected from any one of a saturated aliphatic organic group having 1 to 4 carbon atoms or a monovalent organic group having a structure of: wherein p represents a number of methylene groups, p is an integer of 2 to 10, R 10 , R 11 and R 12 are independently selected from any one of a hydrogen atom, a methyl group, an ethyl group or a propyl group.

[0032] As the polyamic acid ester precursor, the Z group is selected from a phenolic hydroxyl end-capping agent with a photoactive group (such as maleimide, styrene, methacrylic acid, etc.). In the subsequent photo-curing process, the photoactive group introduced by the end-capping agent can undergo photo-crosslinking reaction with a methacrylate crosslinking agent. The construction of such crosslinking network significantly improves the thermal stability of the final cured film.

[0033] As a preferred solution, the preparation method of the polyamic acid ester comprises the following steps:

[0034] B1: reacting a tetracarboxylic dianhydride containing an X group, an alcohol containing R8 and an alcohol containing R9 to prepare a partially esterified tetracarboxylic acid; or reacting a tetracarboxylic dianhydride containing an X group, an alcohol containing R8, an alcohol containing R9 and a saturated aliphatic alcohol having 1 to 4 carbon atoms to prepare a partially esterified tetracarboxylic acid;

[0035] B2: mixing and reacting the partially esterified tetracarboxylic acid with an acyl chlorination reagent to obtain an aromatic diacyl dichloride compound, and then adding a monophenol containing a Z group and a diamine containing a Y group to perform amide polycondensation to obtain the polyamic acid ester.

[0036] As a preferred solution, the B1 is performed under catalysis of a basic catalyst, the reaction temperature is 20-50°C, and the reaction time is 4-24h, the basic catalyst includes at least one of DBU or pyridine; in the B2, the partially esterified tetracarboxylic acid is reacted with an acyl chlorination reagent at -15-5°C for 1-3h, and then a monophenol containing a Z group and a diamine containing a Y group are added and reacted at 20-50°C for 1-6h, the acyl chlorination reagent includes at least one of thionyl chloride or oxalyl chloride. In one embodiment, the reaction solvent is selected from ketones or esters, preferably, the reaction solvent is selected from at least one of N-methylpyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, γ-butyrolactone, dimethyl sulfoxide, which can completely dissolve the raw materials and products.

[0037] As a preferred solution, the X group is selected from at least one of the following:

[0038]

[0039] As a preferred solution, the Y group is selected from at least one of the following:

[0040]

[0041] As a preferred solution, the monophenol containing a Z group includes at least one of 4-maleimide phenol, 1-(3-hydroxyphenyl)-1H-pyrrole-2,5-dione, N-(4-carboxy-3-hydroxyphenyl) maleimide, p-hydroxystyrene or m-hydroxystyrene.

[0042] As a preferred embodiment, the alcohol containing R8 or the alcohol containing R9 includes 2-acryloyloxyethanol, 1-acryloyloxy-3-propanol, 2-acrylamide ethanol, hydroxymethyl vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-tert-butoxypropyl acrylate, 2-hydroxy-3 At least one of the following: cyclohexyloxypropyl acrylate, 2-methacryloyloxyethanol, 1-methacryloyloxy-3-propanol, 2-methacrylamide ethanol, 2-hydroxy-3-methoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-phenoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-tert-butoxypropyl methacrylate, and 2-hydroxy-3-cyclohexyloxypropyl methacrylate.

[0043] As a preferred embodiment, the saturated aliphatic alcohols having 1 to 4 carbon atoms include at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, and tert-butanol.

[0044] As a preferred embodiment, the antioxidant is selected from compounds having a phenolic hydroxyl group and a substituent at the ortho position of the phenolic hydroxyl group. More preferably, the antioxidant includes at least one of 2,6-di-tert-butyl-4-methylphenol, 2,5-di-tert-butyl-hydroquinone, isooctyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 4,4'-methylenebis(2,6-di-tert-butylphenol), 6-tert-butyl-3-methylphenol, and 4,4'-butylidenebis(6-tert-butyl-3-methylphenol).

[0045] As a preferred embodiment, the organic solvent is selected from at least one of esters, alcohols, ethers, ketones, sulfoxides, and amides.

[0046] More preferably, the esters include ethyl acetate, n-butyl acetate, isobutyl acetate, amyl 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.

[0047] The ethers include 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.

[0048] The ketones include methyl ethyl ketone, cyclohexanone, cyclopentanone, 2-heptanone, and 3-heptanone.

[0049] The amides include N-methylpyrrolidone, N-ethylpyrrolidone, N,N-dimethylacetamide, and N,N-dimethylformamide.

[0050] Taking into account the solubility of each component and the coating properties of the resin film, the preferred organic solvents are N-methylpyrrolidone, γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether acetate, N,N-dimethylformamide, and N,N-dimethylacetamide.

[0051] As a preferred embodiment, the photocrosslinking agent is selected from at least one of bisphenol A epoxy diacrylate, dipentaerythritol hexaacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, N-vinylpyrrolidone, 1,3-butanediol dimethacrylate, trimethylolpropane trimethacrylate, isobornyl acrylate, and N-vinylcaprolactam.

[0052] As a preferred embodiment, the photoinitiator is selected from at least one of oxime esters, benzophenone, Mischel ketone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, and thioxanthone. More preferably, the photoinitiator is an oxime ester.

[0053] As a preferred embodiment, the thermal polymerization inhibitor is selected from at least one of N-nitrosodiphenylamine, hydroquinone, p-tert-butylcatechol, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol ether diaminetetraacetic acid, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, phenothiazine, 1-nitroso-2-naphthol, N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt, 2-nitroso-1-naphthol, N-nitroso-N-phenylhydroxylamine ammonium salt, 2,6-di-tert-butyl-p-methylphenol, and 5-nitroso-8-hydroxyquinoline.

[0054] The second aspect:

[0055] A negative photosensitive polyimide resin composition is obtained by thermal imidization of the negative photosensitive polyimide precursor resin composition described in the first aspect, wherein the thermal imidization temperature is 180–400°C. More preferably, the thermal imidization temperature is 200–300°C.

[0056] Third aspect:

[0057] The negative photosensitive polyimide precursor resin composition as described in the first aspect, or the negative photosensitive polyimide resin composition as described in the second aspect, is used in semiconductor packaging, interlayer insulation of multilayer circuits, and overlay coating of flexible copper clad laminates. Attached Figure Description

[0058] Figure 1 This is the infrared spectrum of the PI film prepared in Example 9;

[0059] Figure 2 The DMA curve of the PI film prepared in Example 9;

[0060] Figure 3 This is a SEM image of the PI lithography pattern prepared in Example 9. Detailed Implementation

[0061] A method for synthesizing a photosensitive latent thermogenic alkali-generating agent includes the following steps:

[0062] A1:

[0063] Will The reaction yields the esterified product;

[0064] Or The reaction yields the amidated product;

[0065] A2:

[0066] The esterified product or the amidated product and The reaction yields the photosensitive latent thermogenic alkali-producing agent.

[0067] The general structural formula of the photosensitive latent thermogenic alkali-producing agent is:

[0068]

[0069] In the formula, n represents the number of methylene groups, which is an integer from 2 to 10. R1 is selected from any one of ester or amide groups, and R2, R3, R4, R5, R6, and R7 are each independently selected from any one of hydrogen, methyl, ethyl, or propyl groups.

[0070] The reaction temperature of A1 is -15 to 0°C, the reaction time is 5 to 24 hours, and the reaction solvent includes at least one of N-methylpyrrolidone, N,N-dimethylformamide, or N,N-dimethylacetamide; the reaction temperature of A2 is -15 to 15°C, the reaction time is 5 to 24 hours, and the reaction solvent includes at least one of N-methylpyrrolidone, N,N-dimethylformamide, or N,N-dimethylacetamide.

[0071] In an embodiment of the present invention, Selected from

[0072] A method for preparing a polyamide ester includes the following steps:

[0073] B1: Prepare a partially esterified tetracarboxylic acid by reacting a tetracarboxylic acid dianhydride containing an X group, an alcohol containing R8, and an alcohol containing R9; or prepare a partially esterified tetracarboxylic acid by reacting a tetracarboxylic acid dianhydride containing an X group, an alcohol containing R8, an alcohol containing R9, and a saturated aliphatic alcohol having 1 to 4 carbon atoms.

[0074] B2: The partially esterified tetracarboxylic acid is subjected to amide polycondensation with a monophenol containing a Z group and a diamine containing a Y group to obtain the polyamic acid ester.

[0075] The general structural formula of the polyamic acid ester is:

[0076]

[0077] In the formula, m represents the degree of polymerization, which is an integer from 10 to 100; X is a tetravalent organic group containing an aromatic group; Y is a divalent organic group containing an aromatic group; Z is a monovalent aromatic organic group having at least one maleimide or vinyl-substituted group; and R8 and R9 are independently selected from saturated aliphatic organic groups having 1 to 4 carbon atoms or having The structure is a monovalent organic group, where p represents the number of methylene groups, p is an integer from 2 to 10, and R 10 R 11 and R 12 Each atom is independently selected from any one of hydrogen, methyl, ethyl, or propyl.

[0078] The reaction B1 is carried out under the catalysis of an alkaline catalyst at a temperature of 20–50 °C for a time of 4–24 h. The alkaline catalyst includes at least one of DBU or pyridine. In the reaction B2, the partially esterified tetracarboxylic acid is first mixed with an acyl chloride reagent and reacted at -15–5 °C for 1–3 h to obtain an aromatic diacyl chloride diester compound. Then, a monophenol containing a Z group and a diamine containing a Y group are added and reacted at 20–50 °C for 1–6 h. The acyl chloride reagent includes at least one of thionyl chloride or oxalyl chloride.

[0079] The X group is selected from at least one of the following:

[0080]

[0081] The Y group is selected from at least one of the following:

[0082]

[0083] The monophenol containing the Z group includes at least one of 4-maleimide-based phenol, 1-(3-hydroxyphenyl)-1H-pyrrole-2,5-dione, N-(4-carboxy-3-hydroxyphenyl)maleimide, p-hydroxystyrene, or m-hydroxystyrene.

[0084] The alcohols containing R8 or R9 include at least one of 2-acryloyloxyethanol, 1-acryloyloxy-3-propanol, 2-acrylamide ethanol, hydroxymethyl vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-tert-butoxypropyl acrylate, 2-hydroxy-3-cyclohexyloxypropyl acrylate, 2-methacryloyloxyethanol, 1-methacryloyloxy-3-propanol, 2-methacrylamide ethanol, 2-hydroxy-3-methoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-phenoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-tert-butoxypropyl methacrylate, and 2-hydroxy-3-cyclohexyloxypropyl methacrylate.

[0085] The saturated aliphatic alcohols having 1 to 4 carbon atoms include at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, and tert-butanol.

[0086] A negative photosensitive polyimide precursor resin composition comprising:

[0087] 25-35 parts by weight of polyamic acid ester;

[0088] 45-60 parts by weight of organic solvent;

[0089] 5-20 parts by weight of photocrosslinking agent;

[0090] 1-10 parts by weight of photoinitiator;

[0091] 2-5 parts by weight of a photosensitive latent thermogenic alkali-producing agent;

[0092] 0.005-5 parts by weight of thermal polymerization inhibitor;

[0093] 0.01-2 parts by weight of antioxidant.

[0094] The antioxidant is selected from compounds having a phenolic hydroxyl group and a substituent at the ortho position of the phenolic hydroxyl group, including at least one of 2,6-di-tert-butyl-4-methylphenol, 2,5-di-tert-butyl-hydroquinone, isooctyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 4,4'-methylenebis(2,6-di-tert-butylphenol), 6-tert-butyl-3-methylphenol, and 4,4'-butylidenebis(6-tert-butyl-3-methylphenol).

[0095] The organic solvent is selected from at least one of esters, alcohols, ethers, ketones, sulfoxides, and amides.

[0096] The esters include ethyl acetate, n-butyl acetate, isobutyl acetate, amyl 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.

[0097] The ethers include 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.

[0098] The ketones include methyl ethyl ketone, cyclohexanone, cyclopentanone, 2-heptanone, and 3-heptanone.

[0099] The amides include N-methylpyrrolidone, N-ethylpyrrolidone, N,N-dimethylacetamide, and N,N-dimethylformamide.

[0100] The photocrosslinking agent is selected from at least one of bisphenol A epoxy diacrylate, dipentaerythritol hexaacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, N-vinylpyrrolidone, 1,3-butanediol dimethacrylate, trimethylolpropane trimethacrylate, isobornyl acrylate, and N-vinylcaprolactam.

[0101] The photoinitiator is selected from at least one of oxime esters, benzophenone, Mischel ketone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, and thioxanthone. In this embodiment of the invention, the photoinitiator is an oxime ester.

[0102] The thermal polymerization inhibitor is selected from at least one of N-nitrosodiphenylamine, hydroquinone, p-tert-butylcatechol, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol etherdiaminetetraacetic acid, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, phenothiazine, 1-nitroso-2-naphthol, N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt, 2-nitroso-1-naphthol, N-nitroso-N-phenylhydroxylamine ammonium salt, 2,6-di-tert-butyl-p-methylphenol, and 5-nitroso-8-hydroxyquinoline.

[0103] A negative photosensitive polyimide resin composition is obtained by thermal imidization of a negative photosensitive polyimide precursor resin composition, wherein the thermal imidization temperature is 180–400°C. In this embodiment of the invention, the thermal imidization temperature is 230°C.

[0104] Test method:

[0105] 1. Characterization of weight-average molecular weight and polymer dispersibility index:

[0106] The polymer weight-average molecular weight M involved in the embodiments of the present invention w The polymer dispersibility index (PDI) was obtained by gel permeation chromatography (GPC). The tests were performed on a Waters Model 717plus autosampler equipped with a Waters Model 1515 isobaric high-performance liquid chromatography pump. N,N-dimethylformamide (DMF) and 0.05M lithium bromide (LiBr) were used as eluents, and polymethyl methacrylate (PMMA) of known molecular weight was used as an internal standard.

[0107] 2. Characterization of the degree of imidization (DOI):

[0108] The PSPI adhesive was diluted and spin-coated onto a potassium bromide film. After UV exposure, imidization was performed at different temperatures. The degree of imidization (DOI) of the sample was calculated using data from IR transmission mode, which can be expressed by the following formula:

[0109]

[0110] Where S corresponds to the integrated area of ​​the absorption peak in the FT-IR spectrum. For example, S 1380S represents the integral area of ​​the absorption peak representing the stretching vibration of the CNC bond in the imide ring. 1500 S' represents the integral area of ​​the absorption peak of the benzene ring skeleton. 1380 and S` 1500 This represents the integral area of ​​the absorption peak that has been fully imidized at 350°C.

[0111] 3. Thermal performance characterization:

[0112] The glass transition temperature (Tg) of the PSPI thin film was measured using a TA Instruments DMA analyzer (Q 800). g The frequency is 1 Hz, and the heating rate is 3℃ / min. -1 .

[0113] 4. Adhesion performance characterization:

[0114] On a 90° peeling apparatus (Guangdong Aisi Instrument Technology Co., Ltd.), at a depth of 3 cm min... -1 The adhesion performance of the cured PI film to Cu was tested at a certain speed.

[0115] 5. Photolithography performance characterization:

[0116] The PI photoresist pattern was created using a 365 nm UV lithography machine (ABM / 6 / 350 / NUV / DCCD / M, ABM Inc.). The photolithography performance of PSPI was characterized using a field emission scanning electron microscope (SEM, Hitachi S-4800) equipped with an energy dispersive spectroscopy (EDS) instrument.

[0117] Example 1

[0118] A method for synthesizing a photosensitive latent thermogenic alkali-generating agent includes the following steps:

[0119] Methacrylamide chloride (6.53 g, 62.5 mmol) was added dropwise to an anhydrous N-methylpyrrolidone (NMP) solution of 1-(3-aminopropyl)imidazole (6.26 g, 50.0 mmol) at 0 °C, and stirred in the dark at 25 °C for 24 h. After the reaction was complete, the mixture was poured into deionized water, and the pH was adjusted to approximately 8 with potassium bicarbonate. Subsequently, the solution was extracted five times with dichloromethane. After evaporating the dichloromethane at room temperature, a yellow oily liquid was obtained, which was named NIPM.

[0120] The NIPM was characterized using nuclear magnetic resonance, and the results are as follows: 1H NMR (500MHz, Chloroform-d) δ: 7.60 (t, J=4.6Hz, 1H), 7.53 (t, J=1.6Hz, 1H), 7.07 (dd, J=3.8, 1.7Hz, 1H), 6.86 (dd, J=3.8, 1.8Hz, 1H), 5.81 (dq , J=2.9, 1.5Hz, 1H), 5.58 (dq, J=2.9, 1.5Hz, 1H), 4.03 (t, J=6.4Hz, 2H), 3.20 (td, J=5.3, 4.5Hz, 2H), 2.00-1.91 (m, 1H), 1.87 (t, J=1.4Hz, 3H).

[0121] Finally, acrylic acid (0.79 g, 11 mmol) was added dropwise to an anhydrous NMP solution of NIPM (1.93 g, 10 mmol), and stirred at room temperature in the dark for 8 h to obtain NIPM acrylate.

[0122]

[0123] Example 2

[0124] The synthesis method of this embodiment is basically the same as that of Example 1, except that 1-(3-aminopropyl)imidazole is replaced with an equimolar amount of 2-imidazole-1-ethylamine to obtain HIPM acrylate.

[0125]

[0126] Example 3

[0127] The synthesis method of this embodiment is basically the same as that of Example 1, except that 1-(3-aminopropyl)imidazolium is replaced with an equimolar amount of 3-(1H-imidazol-1-yl)propane-1-ol to obtain NIOM acrylate.

[0128]

[0129] Example 4

[0130] The synthesis method of this embodiment is basically the same as that of Example 1, except that 1-(3-aminopropyl)imidazole is replaced with an equimolar amount of 1-(2-hydroxyethyl)imidazole to obtain HIOM acrylate.

[0131]

[0132] Comparative Example 1

[0133] The synthesis method of this comparative example is basically the same as that of Example 1, except that 1-(3-aminopropyl)imidazolium is replaced with an equimolar amount of 3-phenyl-1-propane to obtain a mixture of NPPM and acrylic acid.

[0134]

[0135] Comparative Example 2

[0136] The synthesis method of this comparative example is basically the same as that of Example 1, except that 1-(3-aminopropyl)imidazole is replaced with an equimolar amount of 3-phenylpropanol to obtain a mixture of HPPM and acrylic acid.

[0137]

[0138] Example 5

[0139] 3,3',4,4'-biphenyltetracarboxylic dianhydride (5.88 g, 20.0 mmol), hydroxyethyl 2-methacrylate (5.20 g, 40.0 mmol), hydroquinone (0.01 g, 0.09 mmol), and 1,8-diazabicyclo[5.4.0]undec-7-ene (0.42 g, 2.7 mmol) were dissolved in anhydrous NMP (24 mL). After stirring at 45 °C in the dark for 24 h, the mixture was cooled to -15 °C and thionyl chloride (4.88 g, 41.0 mmol) was added in three equal portions. The mixture was kept at -15 °C for another 2 h, and then 4-maleiminophenol (0.36 g, 1.9 mmol), 4,4'-diaminodiphenyl ether (3.81 g, 19.0 mmol), pyridine (4.6 mL, 57.0 mmol), and anhydrous NMP (15 mL) were added. After stirring at 25°C for 3 hours, the mixture was poured into a mixed solution of ethanol and deionized water (V:V = 3:7), washed three times, and the precipitate was collected and dried at 50°C to obtain PAE resin, named PAE-1 (structure shown in Formula 1). M was determined by GPC. w =31000g mol -1 PDI = 1.82.

[0140]

[0141] Example 6

[0142] The preparation method in this embodiment is basically the same as that in Example 5, except that 4,4'-diaminodiphenyl ether is replaced with an equimolar amount of 4,4'-diaminodiphenylmethane to obtain PAE-2 resin (structure shown in Formula 2). GPC measured M... w =30000g mol -1 PDI = 1.73.

[0143]

[0144] Example 7

[0145] The preparation method in this embodiment is basically the same as that in Example 5, except that 4,4'-diaminodiphenyl ether is replaced with an equimolar amount of 4,4'-diaminodiphenyl sulfone to obtain PAE-3 resin (structure shown in Formula 3). GPC measured M... w =29000g mol -1 PDI = 1.77.

[0146]

[0147] Example 8

[0148] The preparation method in this embodiment is basically the same as that in Example 5, except that 4-maleimide-based phenol is replaced with an equimolar amount of 4-vinylphenol to obtain PAE-4 resin (structure shown in Formula 4). GPC measured M... w =32000gmol -1 PDI = 1.86.

[0149]

[0150] Comparative Example 3

[0151] The preparation method of this comparative example is basically the same as that of Example 5, except that 4-maleimide-phenol is replaced with an equimolar amount of aniline to obtain PAE-5 resin (structure shown in Formula 5). GPC measured M... w =31000g mol -1 PDI = 1.84.

[0152]

[0153] Example 9

[0154] 31 parts by weight of the PAE-1 resin prepared in Example 5 were dissolved in 60 parts by weight of N-methylpyrrolidone (NMP), and then 2 parts by weight of photoinitiator (OXE-2), 4.5 parts by weight of photocrosslinking agent (tetraethylene glycol dimethacrylate), 2 parts by weight of photosensitive latent thermogenic alkali-generating agent (NIPM acrylate) prepared in Example 1, 0.25 parts by weight of thermal polymerization inhibitor (N-nitrosodiphenylamine), and 0.25 parts by weight of antioxidant (6-tert-butyl-3-methylphenol) were added. The mixture was stirred at room temperature in the dark for 6 hours to obtain the photosensitive polyimide precursor resin composition PSPI-1.

[0155] Preparation of cured thin films with photolithographic patterns:

[0156] At room temperature, PSPI-1 solution was coated onto a silicon wafer at 4000 rpm for 1 min. It was then pre-baked at 100°C for 2 min to remove most of the solvent. The silicon wafer was then exposed using an i-line (365 nm) photomask at an exposure dose of 150 mJ / cm². -2 After exposure, the film was developed with cyclopentanone and then rinsed in propylene glycol methyl ether acetate to achieve photoimaging of the PAE film. Finally, the wafer with the resin film was cured at 230°C for 2 hours under N2 atmosphere. The resulting cured film was named PI-1.

[0157] from Figure 1 The FT-IR spectrum showed that the PI-1 film cured at 30℃ was at 1784 cm⁻¹. -1 (Asymmetrical) and 1716cm -1 The absorption peak of the (symmetric) imide ring C=O, and 1379 cm⁻¹ -1 The presence of CN absorption peaks around the left and right indicates the successful preparation of PI.

[0158] from Figure 2 The DMA curves show that the glass transition temperature (T) of PI-1 is... g The temperature is 261℃.

[0159] from Figure 3 The SEM images show that the lithographic resolution of PI-1 is approximately 6.1 μm.

[0160] Example 10

[0161] A photosensitive polyimide precursor resin composition was prepared according to the method of Example 9, except that NIPM acrylate was replaced with an equal mass of HIPM acrylate prepared in Example 2, resulting in a photosensitive polyimide precursor resin composition PSPI-2, and the cured film was named PI-2.

[0162] Example 11

[0163] A photosensitive polyimide precursor resin composition was prepared according to the method of Example 9, except that NIPM acrylate was replaced with an equal mass of NIPM acrylate prepared in Example 3, resulting in a photosensitive polyimide precursor resin composition PSPI-3, and the cured film was named PI-3.

[0164] Example 12

[0165] A photosensitive polyimide precursor resin composition was prepared according to the method of Example 9, except that PAE-1 resin was replaced with an equal mass of PAE-2 resin prepared in Example 6, resulting in a photosensitive polyimide precursor resin composition PSPI-4, and the cured film was named PI-4.

[0166] Example 13

[0167] A photosensitive polyimide precursor resin composition was prepared according to the method of Example 9, except that PAE-1 resin was replaced with an equal mass of PAE-3 resin prepared in Example 7, resulting in a photosensitive polyimide precursor resin composition PSPI-5, and the cured film was named PI-5.

[0168] Example 14

[0169] A photosensitive polyimide precursor resin composition was prepared according to the method of Example 9, except that PAE-1 resin was replaced with an equal mass of PAE-4 resin prepared in Example 8, resulting in a photosensitive polyimide precursor resin composition PSPI-6, and the cured film was named PI-6.

[0170] Comparative Example 4

[0171] A photosensitive polyimide precursor resin composition was prepared according to the method of Example 9, except that NIPM acrylate was replaced with a mixture of NPPM and acrylic acid prepared in Comparative Example 1 by equal mass, resulting in a photosensitive polyimide precursor resin composition DPSPI-1, and the cured film was named DPI-1.

[0172] Comparative Example 5

[0173] A photosensitive polyimide precursor resin composition was prepared according to the method of Example 9, except that NIPM acrylate was replaced with a mixture of HPPM and acrylic acid prepared in Comparative Example 2 by equal mass, resulting in a photosensitive polyimide precursor resin composition DPSPI-2, and the cured film was named DPI-2.

[0174] Comparative Example 6

[0175] A photosensitive polyimide precursor resin composition was prepared according to the method of Example 9, except that PAE-1 resin was replaced with PAE-5 resin prepared in Comparative Example 3 by an equal mass, resulting in a photosensitive polyimide precursor resin composition DPSPI-3, and the cured film was named DPI-3.

[0176] Effect test

[0177] 1. Characterization of degree of imidization (DOI):

[0178] The PSPI adhesive was diluted and spin-coated onto a potassium bromide film. After UV exposure, imidization was performed at different temperatures. The degree of imidization (DOI) of the sample was calculated using data from IR transmission mode, which can be expressed by the following formula:

[0179]

[0180] Where S corresponds to the integral area of ​​the absorption peak in the FT-IR spectrum. 1380 S represents the integral area of ​​the absorption peak representing the stretching vibration of the CNC bond in the imide ring. 1500 S' represents the integral area of ​​the absorption peak of the benzene ring skeleton. 1380 and S` 1500 This represents the integral area of ​​the absorption peak that has been fully imidized at 350°C.

[0181] 2. Thermal performance characterization:

[0182] The glass transition temperature (Tg) of the PSPI thin film was measured using a TA Instruments DMA analyzer (Q 800). g The frequency is 1 Hz, and the heating rate is 3℃ / min. -1 .

[0183] 3. Adhesion performance characterization:

[0184] On a 90° peeling apparatus (Guangdong Aisi Instrument Technology Co., Ltd.), at a depth of 3 cm min... -1 The adhesion performance of the cured PI film to Cu was tested at a certain speed.

[0185] 4. Photolithography performance characterization:

[0186] The PI photoresist pattern was created using a 365 nm UV exposure machine (ABM / 6 / 350 / NUV / DCCD / M, ABM Inc.). The lithographic performance of PSPI, i.e., aperture resolution, was characterized using a field emission scanning electron microscope (SEM, Hitachi S-4800) equipped with an energy dispersive spectroscopy (EDS) instrument.

[0187] The PI films or DPI films prepared in Examples 9-14 and Comparative Examples 4-6 were characterized for their imide content, thermal properties, adhesive properties, and patterning properties. The results are shown in Table 1.

[0188] Table 1

[0189]

[0190] Compared to Comparative Examples 4-5, the PAE resin in this embodiment exhibited a higher degree of imidization after curing at 230°C following the addition of the photosensitive latent thermogenic alkali-generating agent prepared according to this invention to the PSPI adhesive. This is because the ionic bonds in its molecular structure dissociate upon heating, generating a basic imidazole nitrogen heterocycle and a highly polar carboxyl group with low-temperature catalytic activity, thus achieving low-temperature curing of the PAE resin. Secondly, this additive contains photosensitive acrylate groups, which can participate in the crosslinking network of photoinitiated free radical polymerization. The nitrogen atoms and carboxyl groups of the imidazole ring retained after curing have a coordination effect with copper, improving the adhesion between the low-temperature cured film and the copper foil.

[0191] Compared to Comparative Example 6, Examples 9 and 14 exhibited higher glass transition temperatures. This is because the terminal ester structures of PAE-1 and PAE-4 remain stable and do not undergo ring-closing reactions during the curing stage. The PI chain undergoes photocrosslinking with methacrylate crosslinking agents through active groups (maleimide, styrene, etc.), thereby improving the thermal stability of the film. Experiments also revealed that the addition of the photosensitive latent thermogenic alkali-generating agent prepared according to this invention does not affect the photolithographic properties of the photosensitive polyimide precursor resin composition.

[0192] The results show that the photosensitive polyimide precursor resin composition prepared by the present invention has good low-temperature curing and photopatterning properties, and the cured film has good thermal stability and good adhesion to copper foil, and can be applied to the field of advanced electronic packaging.

[0193] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. Those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the protection scope of the present invention.

Claims

1. A negative photosensitive polyimide precursor resin composition, characterized in that, include: 25-35 parts by weight of polyamic acid ester; 45-60 parts by weight of organic solvent; 5-20 parts by weight of photocrosslinking agent; 1-10 parts by weight of photoinitiator; 2-5 parts by weight of a photosensitive latent thermogenic alkali-producing agent; 0.005-5 parts by weight of thermal polymerization inhibitor; 0.01-2 parts by weight of antioxidant; The general structural formula of the photosensitive latent thermogenic alkali-producing agent is as follows: In the formula, n represents the number of methylene groups, which is an integer from 2 to 10. R1 is selected from any one of ester or amide groups, and R2, R3, R4, R5, R6, and R7 are each independently selected from any one of hydrogen, methyl, ethyl, or propyl groups.

2. The negative photosensitive polyimide precursor resin composition according to claim 1, characterized in that, The preparation method of the photosensitive latent thermogenic alkali-generating agent includes the following steps: A1： Will The reaction yields the esterified product; Or The reaction yields the amidated product; A2： The esterified product or the amidated product and The reaction yields the photosensitive latent thermogenic alkali-producing agent; The reaction temperature of A1 is -15 to 0°C, the reaction time is 5 to 24 hours, and the reaction solvent includes at least one of N-methylpyrrolidone, N,N-dimethylformamide, or N,N-dimethylacetamide; the reaction temperature of A2 is -15 to 15°C, the reaction time is 5 to 24 hours, and the reaction solvent includes at least one of N-methylpyrrolidone, N,N-dimethylformamide, or N,N-dimethylacetamide.

3. The negative photosensitive polyimide precursor resin composition according to claim 1, characterized in that, The general structural formula of the polyamic acid ester is: In the formula, m represents the degree of polymerization, which is an integer from 10 to 100; X is a tetravalent organic group containing an aromatic group; Y is a divalent organic group containing an aromatic group; Z is a monovalent aromatic organic group having at least one maleimide or vinyl-substituted group; and R8 and R9 are independently selected from saturated aliphatic organic groups having 1 to 4 carbon atoms or having The structure is a monovalent organic group, where p represents the number of methylene groups, p is an integer from 2 to 10, and R 10 R 11 and R 12 Each atom is independently selected from any one of hydrogen, methyl, ethyl, or propyl.

4. The negative photosensitive polyimide precursor resin composition according to claim 3, characterized in that, The preparation method of the polyamide ester includes the following steps: B1: Prepare a partially esterified tetracarboxylic acid by reacting a tetracarboxylic acid dianhydride containing an X group, an alcohol containing R8, and an alcohol containing R9; or prepare a partially esterified tetracarboxylic acid by reacting a tetracarboxylic acid dianhydride containing an X group, an alcohol containing R8, an alcohol containing R9, and a saturated aliphatic alcohol having 1 to 4 carbon atoms. B2: The partially esterified tetracarboxylic acid is mixed and reacted with an acyl chloride reagent to obtain an aromatic diacyl chloride diester compound. Then, a monophenol containing a Z group and a diamine containing a Y group are added for amide polycondensation to obtain the polyamic acid ester.

5. The negative photosensitive polyimide precursor resin composition according to claim 4, characterized in that, The reaction B1 is carried out under the catalysis of an alkaline catalyst at a temperature of 20–50 °C for a time of 4–24 h. The alkaline catalyst includes at least one of DBU or pyridine. In the reaction B2, the partially esterified tetracarboxylic acid is first mixed with an acyl chloride reagent and reacted at -15–5 °C for 1–3 h to obtain an aromatic diacyl chloride diester compound. Then, a monophenol containing a Z group and a diamine containing a Y group are added and reacted at 20–50 °C for 1–6 h. The acyl chloride reagent includes at least one of thionyl chloride or oxalyl chloride.

6. The negative photosensitive polyimide precursor resin composition according to claim 3, characterized in that, The X group is selected from at least one of the following: The Y group is selected from at least one of the following: The monophenol containing the Z group includes at least one of 4-maleimide-based phenol, 1-(3-hydroxyphenyl)-1H-pyrrole-2,5-dione, N-(4-carboxy-3-hydroxyphenyl)maleimide, p-hydroxystyrene, or m-hydroxystyrene.

7. The negative photosensitive polyimide precursor resin composition according to claim 1, characterized in that, The antioxidant is selected from compounds having a phenolic hydroxyl group and a substituent at the ortho position of the phenolic hydroxyl group.

8. The negative photosensitive polyimide precursor resin composition according to claim 1, characterized in that, The organic solvent is selected from at least one of esters, alcohols, ethers, ketones, sulfoxides, and amides; The photocrosslinking agent is selected from at least one of bisphenol A epoxy diacrylate, dipentaerythritol hexaacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, N-vinylpyrrolidone, 1,3-butanediol dimethacrylate, trimethylolpropane trimethacrylate, isobornyl acrylate, and N-vinylcaprolactam. The photoinitiator is selected from at least one of oxime esters, benzophenone, mifepristone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, and thioxanthone. The thermal polymerization inhibitor is selected from at least one of N-nitrosodiphenylamine, hydroquinone, p-tert-butylcatechol, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol etherdiaminetetraacetic acid, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, phenothiazine, 1-nitroso-2-naphthol, N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt, 2-nitroso-1-naphthol, N-nitroso-N-phenylhydroxylamine ammonium salt, 2,6-di-tert-butyl-p-methylphenol, and 5-nitroso-8-hydroxyquinoline.

9. A negative photosensitive polyimide resin composition, characterized in that, It is obtained by thermal imidization of the negative photosensitive polyimide precursor resin composition according to any one of claims 1-8, wherein the thermal imidization temperature is 180-400°C.

10. The negative photosensitive polyimide precursor resin composition as described in any one of claims 1-8, or the negative photosensitive polyimide resin composition as described in claim 9, is used in semiconductor packaging, interlayer insulation of multilayer circuits, and overlay coating of flexible copper clad laminates.

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