A negative photosensitive polyimide resin, a method for preparing the same, a photoresist composition, and use thereof

Abstract

The application provides a negative photosensitive polyimide resin and a preparation method thereof, and a photoresist composition containing the negative photosensitive polyimide resin and application thereof. The negative photosensitive polyimide resin is obtained through polymerization of dianhydride monomers and diamine monomers in sequence, dehydration imidization reaction of a dehydrating agent and a catalyst in the presence of a solvent, and finally addition of a photosensitive tertiary amine. The photoresist composition contains the negative photosensitive polyimide resin, a crosslinking agent, a photosensitizer, a photoinitiator and a solvent. The photoresist composition has low-temperature curing characteristics and good copper adhesion, and can be widely applied in the field of advanced semiconductor packaging.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of resins for photoresists, and particularly relates to a negative photosensitive polyimide resin, a preparation method thereof, a photoresist composition and application. BACKGROUND

[0002] In the formation process of the internal structure of a semiconductor device, a photoetching technology is needed, which can draw geometric pattern structures on a photoresist layer by exposure and development, and then form various circuit structures. The photoresist can be divided into positive resist and negative resist according to the pattern type.

[0003] In advanced packaging technology, a fan-out wafer level packaging technology is widely concerned. This technology can expand the chip I / O structure to outside the chip, greatly expand the design freedom, integrate multiple chips with different functions into one package, and realize system-level packaging. The redistribution layer is the core structure of the fan-out wafer level packaging.

[0004] Polyimide (PI) is a kind of polymer material with good dielectric properties, high mechanical strength and strong heat resistance, which is widely used in electrical, aerospace and automotive industries. Especially in the semiconductor field, PI is widely used as an important insulating material as a stress buffer layer, a dielectric insulating layer, a surface passivation layer, and a surface planarization layer and a protective layer of the redistribution layer in wafer level packaging.

[0005] In the formation process of the redistribution layer, a photosensitive polyimide photoresist material is needed as a Cu / Ti alloy sputtering base and a patterning tool, and then as a stress buffer layer and a dielectric insulating layer in the packaging structure.

[0006] The curing temperature of the traditional photosensitive polyimide is generally high, all above 300℃, but it cannot meet the requirements of the current advanced semiconductor packaging process. At such a temperature, the wafer may be warped, the low-melting-point solder balls may be cracked, detached or recrystallized, and high-temperature curing will produce very large residual stress, which may damage the underlying structure, affect the dielectric properties, and cause the device function to decrease or even be damaged.

[0007] Therefore, in order to meet the requirements of the current advanced semiconductor packaging process, it is necessary to develop a negative photosensitive polyimide photoresist with low-temperature curing function. SUMMARY

[0008] In view of the problems in the prior art, the present application provides a negative photosensitive polyimide resin which can endow the photoresist composition with low-temperature curing properties, a preparation method thereof, a photoresist composition and application.

[0009] In particular, one aspect of the present application provides a negative photosensitive polyimide resin having low temperature curing characteristics, the negative photosensitive polyimide resin having a structure represented by Formula I:

[0010]

[0011] wherein Ar1 is a tetravalent group containing two benzene rings;

[0012] Ar2 is a divalent group containing two or more benzene rings and one or more ether bonds;

[0013] x = (S 1659 / S 1500 ) T / (S 1659 / S 1500 ) T’ , x is 0.78 to 0.91;

[0014] wherein (S 1659 / S 1500 ) T is a ratio of a characteristic peak area at 1659 cm -1 to a characteristic peak area at 1500 cm -1 of an infrared spectrum of the negative photosensitive polyimide resin, (S 1659 / S 1500 ) T’ is a ratio of a characteristic peak area at 1659 cm -1 to a characteristic peak area at 1500 cm -1 of an infrared spectrum of the polymer after treatment with a dehydrating agent and a catalyst;

[0015] n = Mw / Mr, n is 300 to 1300;

[0016] wherein Mw is a weight average molecular weight of the polymer obtained using a permeation gel chromatography, and Mr is a relative molecular mass of a repeating unit of the polymer.

[0017] In one or more embodiments, Ar1 is selected from one or more of the following groups:

[0018]

[0019] In one or more embodiments, Ar2 is selected from one or more of the following groups:

[0020]

[0021] In one or more embodiments, Ar1 is selected from one or more of the following groups:

[0022]

[0023]

[0024] Furthermore, Ar2 is selected from one or more of the following groups:

[0025]

[0026] Another aspect of the present application provides a method for preparing a negative photosensitive polyimide resin, comprising the following steps:

[0027] (1) dissolving a diamine monomer in an organic solvent, adding a dianhydride monomer, and performing a polymerization reaction at -5°C to 10°C for 8 to 14 hours to obtain a polyamic acid liquid;

[0028] (2) washing and drying the polyamic acid liquid to obtain a polyamic acid solid, and dissolving the polyamic acid solid in an organic solvent to obtain an intermediate, the mass of the polyamic acid in the intermediate being 10wt% to 50wt% of the total mass of the intermediate;

[0029] (3) adding a dehydrating agent and a catalyst to the intermediate, and performing a dehydration imidization reaction at room temperature for 4 to 10 hours to obtain a negative photosensitive polyimide resin X;

[0030] (4) adding a photosensitive tertiary amine to the negative photosensitive polyimide resin X, and stirring at room temperature for 6 to 12 hours to obtain a negative photosensitive polyimide resin Y;

[0031] wherein the structure of the dianhydride monomer is the structure of the diamine monomer is H2N-Ar2-NH2;

[0032] the unit structure of the negative photosensitive polyimide resin X is shown in formula (II);

[0033]

[0034] the unit structure of the negative photosensitive polyimide resin Y is shown in formula (I), wherein the proportion of the unit structure shown in formula (II) in Y is x, and the proportion of the unit structure shown in formula (III) in Y is (1-x);

[0035]

[0036] In one or more embodiments, the method for preparing a negative photosensitive polyimide resin is characterized in that,

[0037] In step (1), the molar ratio of the dianhydride monomer to the diamine monomer is (1.01-1.1):1;

[0038] In steps (1) and (2), the organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, γ-butyrolactone, N-methylpyrrolidone, ethyl lactate, butyl lactate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether and diethylene glycol diethyl ether, propylene glycol monomethyl ether, and isopropyl alcohol;

[0039] In step (3), the dehydrating agent is selected from one or more of acetic anhydride, maleic anhydride, trifluoroacetic anhydride, and N,N'-dicyclohexyl carbodiimide; the catalyst is selected from one or more of triethylamine, pyridine, diethyl ethanolamine, quinoline, and isoquinoline; and the reaction temperature is 0-30°C.

[0040] In one or more embodiments, the method for preparing a negative photosensitive polyimide resin is characterized in that, in step (4), the mass ratio of the photosensitive tertiary amine to the intermediate polyamic acid solid is 1:(1-2.5); the reaction temperature is 0-30°C; and the photosensitive tertiary amine is selected from one or more of N-methyldiethanolamine, N-ethyldiethanolamine, N-methyl-4-aminobenzoate, dimethylaminoethyl methacrylate, and diethylaminoethyl methacrylate.

[0041] Another aspect of the present application provides a negative photosensitive polyimide resin prepared using the method for preparing a negative photosensitive polyimide resin described in any of the embodiments herein.

[0042] The present application provides a negative photosensitive polyimide photoresist composition, which includes a negative photosensitive polyimide resin grafted with dimethylaminoethyl methacrylate via ionic bonding to a polyamic acid containing an ether bond of a specific structure during synthesis, and which has a low-temperature curing property via chemical imidization, and which has good adhesion to copper due to the ether bond structure in the negative photosensitive polyimide main chain.

[0043] The present application provides a negative photosensitive polyimide photoresist composition, which includes a crosslinking agent of a specific structure, and which can ensure a clear and complete pattern after curing.

[0044] Another aspect of the present application provides a negative photosensitive polyimide photoresist composition, which includes the negative photosensitive polyimide resin described in any of the embodiments herein, and further includes an organic solvent, a crosslinking agent, a photosensitizer, and a photoinitiator.

[0045] The content of the negative photosensitive polyimide resin Y in the photoresist composition is 10 wt% to 50 wt%, the content of the organic solvent is 40 wt% to 85 wt%, the content of the crosslinking agent is 0.1 wt% to 5 wt%, the content of the photosensitizer is 1 wt% to 10 wt%, and the content of the photoinitiator is 1 wt% to 10 wt%, based on the total mass of the negative photosensitive polyimide photoresist composition.

[0046] In one or more embodiments, the organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, γ-butyrolactone, N-methylpyrrolidone, ethyl lactate, butyl lactate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether and diethylene glycol diethyl ether, propylene glycol monomethyl ether, and isopropyl alcohol.

[0047] In one or more embodiments, the crosslinking agent is a compound having a methacrylic acid structure or an acrylic acid structure. It is selected from one or more of glycidyl methacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, ethylene glycol diacrylate, and hexafluoroacrylate.

[0048] In one or more embodiments, the photosensitizer is a compound having a benzophenone structure, selected from one or more of benzophenone, 4,4'-diamino benzophenone, and (dimethylamino) benzophenone compounds.

[0049] In one or more embodiments, the photoinitiator is a compound containing a benzophenone structure / imidazole structure / hydroxyl ester structure, selected from one or more of 2-phenyl benz-2-dimethylamine-1-(4-morpholinobenzyl phenyl) butanone, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyl oxime), and the like.

[0050] The present application also provides the use of the negative photosensitive polyimide photoresist composition described in any one of the embodiments herein in semiconductor packaging.

[0051] The present application has obtained a negative photosensitive polyimide resin capable of realizing low-temperature curing by grafting a photosensitive tertiary amine methacrylate dimethylaminoethyl ester onto a specific structure of polyamic acid containing an ether bond through ionic bond action and by chemical imidization. The ether bond structure contained in the main chain of the negative photosensitive polyimide of the present application can realize good adhesion to copper, and the specific structure of the crosslinking agent can ensure the clear and complete pattern after curing. BRIEF DESCRIPTION OF DRAWINGS

[0052] Figure 1 The infrared spectrum of the negative photosensitive polyimide photoresist resin.

[0053] Figure 2 An infrared spectrum of the photoresist film after curing the negative photosensitive polyimide photoresist. DETAILED DESCRIPTION

[0054] To enable persons skilled in the art to understand the features and effects of the present application, the following is a general description and definition of the terms and phrases mentioned in this document. Unless otherwise specified, all technical and scientific words used in this document have their usual meanings understood by those skilled in the art of the present application, and in the event of a conflict, the definitions in this specification shall prevail.

[0055] Theories or mechanisms described and disclosed herein, whether correct or not, should not be considered limiting on the scope of the present application, that is, the present application can be implemented without regard to any particular theory or mechanism.

[0056] In this document, "comprise", "include", "contain", and similar phrases encompass the meanings of "consist essentially of" and "consist of", for example, when this document discloses that "A comprises B and C", "A consists essentially of B and C" and "A consists of B and C" should be considered to have been disclosed herein.

[0057] In this document, all features defined by numerical ranges or percentage ranges, such as values, amounts, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to have encompassed and specifically disclosed all possible sub-ranges and individual numerical values within the range (including integers and fractions).

[0058] In this document, unless otherwise specified, percentages refer to mass percentages, and ratios refer to mass ratios.

[0059] In this document, the sum of the percentages of the components of a composition is 100%.

[0060] In this document, when describing embodiments or examples, it should be understood that they are not intended to limit the present application to these embodiments or examples. Rather, all alternatives, modifications, and equivalents of the methods and materials described herein that are within the scope of the present application are to be included herein.

[0061] In this document, for the sake of brevity, all possible combinations of the technical features in each embodiment or example are not described. Therefore, as long as the combinations of the technical features do not contradict each other, the technical features in each embodiment or example can be combined arbitrarily, and all possible combinations should be considered to be within the scope of the present specification.

[0062] In this document, hexafluoro dianhydride is the abbreviation for 4,4'-(hexafluoroisopropylidene)diphthalic anhydride.

[0063] Negative photosensitive polyimide resin

[0064] The negative photosensitive polyimide resin of the present application can have a structure shown in Formula I:

[0065]

[0066] wherein Ar1 is a tetravalent group containing two benzene rings;

[0067] Ar2 is a divalent group containing two or more benzene rings and one or more ether bonds;

[0068] x is the number ratio between the two structural units, x = (S 1659 / S 1500 ) T / (S 1659 / S 1500 ) T’ , x is 0.7-1. Wherein (S 1659 / S 1500 ) T is the ratio of the characteristic peak area at 1659 cm -1 to the characteristic peak area at 1500 cm -1 of the infrared spectrum of the polymer, (S 1659 / S 1500 ) T’ is the ratio of the characteristic peak area at 1659 cm -1 to the characteristic peak area at 1500 cm -1 of the infrared spectrum of the polymer after being treated with a dehydrating agent and a catalyst;

[0069] In one or more embodiments, x is 0.7-1; preferably, x is 0.78-0.91; more preferably, x is 0.70, 0.75, 0.78, 0.79, 0.80, 0.81, 0.82, 0.83, 0.84, 0.85, 0.86, 0.87, 0.88, 0.89, 0.90, 0.91, 0.95 or 1.00.

[0070] n is the degree of polymerization, n = Mw / Mr, n is an integer of 3-2000. Wherein Mw is the weight average molecular weight of the polymer obtained using permeation gel chromatography, Mr is the relative molecular mass of the repeating unit of the polymer.

[0071] In one or more embodiments, n is 3 to 2000; preferably, n is 100 to 1800; more preferably, n is 200 to 1500; even more preferably, n is 300 to 1300; even more preferably, n is 390 to 1230; even more preferably, n is 200 to 300, 300 to 400, 400 to 500, 500 to 600, 600 to 700, 700 to 800, 800 to 900, 900 to 1000, 1000 to 1100, 1100 to 1200, 1200 to 1300, 1300 to 1400 or 1400 to 1500.

[0072] In this article, aromatic groups refer to groups containing aromatic rings.

[0073] Preferably, Ar1 is a tetravalent group containing two benzene rings.

[0074] More preferably, Ar1 is selected from one or more of the following groups:

[0075]

[0076] In some preferred embodiments, Ar1 is selected from one or two of the following groups:

[0077]

[0078] Preferably, Ar2 is a divalent group containing multiple benzene rings and one or more ether bonds, such as a divalent group containing two benzene rings and one ether bond. In this document, the ether bond typically serves as the group connecting the two benzene rings. More preferably, Ar2 is a divalent group containing two benzene rings, with the ether bond serving as the group connecting the two benzene rings. In this invention, by introducing ether bonds into Ar2 as flexible groups, the adhesion between the photoresist and copper and the toughness after curing can be improved.

[0079] More preferably, Ar2 is selected from one or more of the following groups:

[0080]

[0081] In some preferred embodiments, Ar2 is selected from one or two of the following groups:

[0082]

[0083] In some preferred embodiments, Ar1 is Ar2 is In some preferred embodiments, Ar1 is Ar2 is In some preferred embodiments, Ar1 is Ar2 is

[0084]

[0085] In some preferred embodiments, Ar1 is Ar2 is

[0086]

[0087] In some preferred embodiments, Ar1 is Ar2 is

[0088]

[0089] In some preferred embodiments, Ar1 is Ar2 is

[0090]

[0091] Process for producing a negative photosensitive polyimide resin

[0092] The present application also provides a method for preparing a negative photosensitive polyimide resin, comprising the following steps:

[0093] (1) dissolving a diamine monomer in an organic solvent, adding a dianhydride monomer, and performing a polymerization reaction at -5°C to 10°C for 8 to 14 hours to obtain a polyamic acid liquid;

[0094] (2) washing and drying the polyamic acid liquid to obtain a polyamic acid solid. The polyamic acid solid is dissolved in an organic solvent to obtain an intermediate;

[0095] (3) adding a dehydrating agent and a catalyst to the intermediate, and performing a dehydration imidization reaction at room temperature for 4 to 10 hours to obtain a negative photosensitive polyimide resin X;

[0096] (4) adding a photosensitive tertiary amine to the negative photosensitive polyimide resin X, and stirring at room temperature for 6 to 12 hours to obtain a negative photosensitive polyimide resin Y;

[0097] In the present application, the structure of the dianhydride monomer is wherein Ar1 is as defined in any embodiment herein; and the structure of the diamine monomer is H2N-Ar2-NH2, wherein Ar2 is as defined in any embodiment herein.

[0098] The unit structure of the negative photosensitive polyimide resin X is shown in formula (II);

[0099]

[0100] The unit structure of the negative photosensitive polyimide resin Y is shown in formula (I), wherein the proportion of the unit structure shown in formula (II) in Y is x, and the proportion of the unit structure shown in formula (III) in Y is (1-x);

[0101]

[0102] In some preferred embodiments, the dianhydride monomer is selected from one or more of the following compounds:

[0103]

[0104] In some preferred embodiments, the diamine monomer is selected from one or more of the following compounds:

[0105]

[0106]

[0107] In step (1) and step (2), the organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, γ-butyrolactone, N-methylpyrrolidone, ethyl lactate, butyl lactate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether and diethylene glycol diethyl ether, propylene glycol monomethyl ether, and isopropyl alcohol; more preferably one or more of N,N-dimethylformamide, N-methylpyrrolidone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and isopropyl alcohol.

[0108] In step (1), the molar ratio of the dianhydride monomer to the diamine monomer is (1.0-1.1):1, preferably 1.01:1, 1.05:1, 1.08:1, 1.10:1.

[0109] In step (1), the reaction temperature is -5℃-10℃, preferably 0℃-5℃, more preferably 0℃, 1℃, 2℃, 3℃, 4℃ or 5℃. In step (1), the reaction time is 8-14h, preferably 8-12h, more preferably 8h, 9h, 10h, 11h or 12h.

[0110] The mass of the polyamic acid in the intermediate of step (2) is 10wt%-50wt% of the total mass of the intermediate, preferably 15wt%-40wt%, more preferably 20-35wt%, more preferably 25-32wt%, more preferably 25-26wt% or 31-32wt%.

[0111] In step (3), the reaction temperature is 0°C to 30°C, preferably 5°C to 25°C, and more preferably 5°C, 10°C, 15°C, 20°C, or 25°C. In step (3), the reaction time is 4 to 10 hours, preferably 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, or 10 hours. Controlling the reaction temperature and reaction time in step (3) within the above ranges is advantageous in obtaining a negative photosensitive polyimide resin that has good solubility, is more stable, and has better performance.

[0112] In step (3), the catalyst is selected from one or more of triethylamine, pyridine, diethylethanolamine, quinoline, and isoquinoline. Preferably, the catalyst is pyridine. The dehydrating agent is selected from one or more of acetic anhydride, maleic anhydride, trifluoroacetic anhydride, and N,N'-dicyclohexylcarbodiimide. Preferably, the dehydrating agent is one or both of acetic anhydride and N,N'-dicyclohexylcarbodiimide.

[0113] In step (4) of the present application, the photosensitive tertiary amine is added, which can introduce a photosensitive group through ionic bonding on the carboxyl group of the polyamic acid, and can also improve the mechanical properties of the cured film of the photoresist made from the negative photosensitive polyimide resin, and enhance the toughness thereof.

[0114] In step (4), the photosensitive tertiary amine is selected from one or more of N-methyldiethanolamine, N-ethyldiethanolamine, N-methyl-4-aminobenzoate, dimethylaminoethyl methacrylate, and diethylaminoethyl methacrylate.

[0115] In step (4), the mass ratio of the photosensitive tertiary amine to the polyamic acid solid is 1:(1 to 2.5), preferably 1:1, 1:1.5, 1:1.67, 1:2, or 1:2.5.

[0116] In step (4), the reaction temperature is 0°C to 30°C, preferably 5°C to 25°C, and more preferably 5°C, 10°C, 15°C, 20°C, or 25°C. In step (4), the reaction time is 6 to 12 hours, preferably 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, or 12 hours.

[0117] Negative photosensitive polyimide resist composition

[0118] The negative photosensitive polyimide photoresist composition of the present application includes a resin, a crosslinking agent, a photosensitizer, a photoinitiator, and a solvent, wherein the resin comprises the negative photosensitive polyimide resin of the present application, or the resin is the negative photosensitive polyimide resin of the present application. In one or more embodiments, the negative photosensitive polyimide photoresist composition of the present application consists of a negative photosensitive polyimide resin, a crosslinking agent, a photosensitizer, a photoinitiator, and a solvent.

[0119] The negative photosensitive polyimide photoresist composition of the present application can be directly used as a photoresist.

[0120] In the present application, the content of the resin in the negative photosensitive polyimide photoresist composition is 10wt%-50wt%, the content of the organic solvent is 40wt%-85wt%, the content of the crosslinking agent is 0.1wt%-5wt%, the content of the photosensitizer is 1wt%-10wt%, and the content of the photoinitiator is 1wt%-10wt%, based on the total weight of the negative photosensitive polyimide photoresist composition. Controlling the content of the resin in the negative photosensitive polyimide photoresist composition within the above range is beneficial to improving the thickness uniformity of the photoresist composition during coating. Adding the crosslinking agent in the negative photosensitive polyimide photoresist composition is beneficial to improving the definition and integrity of the photoresist film pattern after photoetching.

[0121] In one or more embodiments, the content of the resin in the negative photosensitive polyimide photoresist composition is preferably 15wt%-45wt%, more preferably 20wt%-40wt%, more preferably 25wt%-35wt%, and more preferably 25wt%, 30wt% or 35wt%, based on the total weight of the negative photosensitive polyimide photoresist composition.

[0122] In one or more embodiments, the content of the crosslinking agent in the negative photosensitive polyimide photoresist composition is preferably 0.2wt%-0.8wt%, more preferably 0.3wt%-0.5wt%, for example 0.3wt%, 0.35wt%, 0.4wt%, 0.45wt% or 0.5wt%, based on the total weight of the negative photosensitive polyimide photoresist composition.

[0123] In one or more embodiments, the content of the photosensitizer in the negative photosensitive polyimide photoresist composition is preferably 1wt%-6wt%, more preferably 2wt%-5wt%, and more preferably 2wt%-4wt%, and more preferably 2wt%, 3wt% or 4wt%, based on the total weight of the negative photosensitive polyimide photoresist composition.

[0124] In one or more embodiments, the content of the photoinitiator in the negative photosensitive polyimide photoresist composition is preferably 1wt%-10wt%, more preferably 2wt%-8wt%, and more preferably 4wt%, 5wt%, 6wt% or 7wt%, based on the total weight of the negative photosensitive polyimide photoresist composition.

[0125] In the present application, the content of the solvent in the negative photosensitive polyimide photoresist composition is preferably 40wt%-75wt%, and more preferably 40wt%, 41wt%, 45wt%, 46wt%, 50wt%, 55wt%, 60wt%, 65wt%, 70wt% or 75wt%, based on the total weight of the negative photosensitive polyimide photoresist composition.

[0126] When the negative photoresist is exposed to ultraviolet light or electron beam, the photoinitiator in the photoresist absorbs light energy and generates free radicals. The free radicals attack the double bond of the acrylic crosslinking agent, causing the acrylic ester group to open and form new free radicals. These free radicals can further initiate the polymerization reaction of the acrylic ester group to form long-chain polymers.

[0127] The photoinitiator suitable for the present application can absorb light energy and generate free radicals when the negative photoresist is exposed to ultraviolet light or electron beam, such as oxime ester compounds, and the suitable crosslinking agent is selected from one or more of 2-phenylbenz-2-dimethylamine-1-(4-morpholinobenzyl phenyl) butanone, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 1-[4-(phenylthio)phenyl]-1,2-octane dione 2-(O-benzoyl oxime), etc. Preferably, the photoinitiator is 1-[4-(phenylthio)phenyl]-1,2-octane dione 2-(O-benzoyl oxime).

[0128] The crosslinking agent suitable for the present application is an acrylic or methacrylic compound that can react with the free radicals generated by the photoinitiator and form new free radicals, further initiating the polymerization reaction and forming long-chain polymers. Suitable crosslinking agents are selected from one or more of glycidyl methacrylate, triethylene glycol methacrylate, polyethylene glycol dimethacrylate, ethylene glycol diacrylate, and hexafluoroacrylate. Preferably, the crosslinking agent is ethylene glycol diacrylate.

[0129] The photosensitizer suitable for the present application can be a benzophenone compound. Suitable photosensitizers are selected from one or more of benzophenone, 4,4'-diamino benzophenone, and dimethylaminobenzophenone compounds. Preferably, the photosensitizer is Michler's ketone.

[0130] The solvent suitable for the negative photosensitive polyimide photoresist composition of the present application is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, γ-butyrolactone, N-methylpyrrolidone, ethyl lactate, butyl lactate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, and diethylene glycol diethyl ether, propylene glycol monomethyl ether, and isopropyl alcohol.

[0131] The low-temperature curing can be curing at 200°C or below, for example, 180°C or below.

[0132] Use of a negative photosensitive polyimide resist composition

[0133] The negative photosensitive polyimide photoresist composition of the present application can be applied in a semiconductor packaging process, including for preparing a buffer protection layer, a rewiring layer, an interlayer insulating film, a cavity structure, etc.

[0134] The present application will be described in the following with specific examples. It should be understood that these examples are merely illustrative and are not intended to limit the scope of the present application. The methods, reagents and materials used in the examples are conventional in the art unless otherwise specified. The starting compounds in the examples are all commercially available. The products in the preparation process are characterized by infrared spectroscopy in the examples and comparative examples of the present application.

[0135] Example 1: Synthesis of negative photosensitive polyimide photoresist resin R1

[0136] The negative photosensitive polyimide photoresist resin R1 was prepared according to the following steps:

[0137] S1: Under a dry nitrogen stream, 26.668 g of N,N-dimethylformamide (DMF) was added to a three-necked flask, then 0.01 mol (2.00241 g) of diamine monomer (4,4'-diamino diphenyl ether) was added under stirring, and stirred at room temperature for 0.5-1 h until the diamine monomer was completely dissolved. Then 0.0105 mol (4.66452 g) of dianhydride monomer (hexafluoro dianhydride) was added under stirring in three portions with an interval of 0.5-1 h, and reacted at 0°C for 8-10 h to carry out the polymerization reaction, obtaining a polyamic acid;

[0138] S2: After the polymerization reaction was completed, it was cooled to room temperature, and the obtained viscous polymer solution was slowly poured into a large amount of a mixed washing solution of methanol and deionized water (the volume ratio of methanol to deionized water was 1:(1-3)), and washed thoroughly for 3 times, and the washing solution was discarded after each washing. Then a vacuum oven was used for drying at 60°C for 24 h, obtaining a polyamic acid solid; 30 g of the polyamic acid solid was weighed, and dissolved in an appropriate amount of 41 g of an organic solvent to obtain an intermediate. The organic solvent was selected from N,N-dimethylformamide, N-methyl pyrrolidone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether or isopropyl alcohol;

[0139] S3: An appropriate amount of 2.25 g of dehydrating agent (acetic anhydride) and 3.375 g of catalyst (pyridine) were weighed and pre-mixed, and then the pre-mixed liquid was added to the intermediate obtained in S2, and reacted at room temperature in the dark for 4-5 h to carry out the dehydrating imidization reaction, obtaining a negative photosensitive polyimide resin;

[0140] The obtained polymer solid was measured for infrared absorption spectrum, and the results are shown in Figure 1 The amide I band and amide II band of amide group, i.e. the carbonyl stretching vibration and NH bending vibration in amide group and C—N stretching vibration, were detected at 1659 cm -1 nearby, and the C=O stretching vibration in aromatic acid carboxyl was detected at 1718 cm -1 nearby.-1 There is a weak amide acid characteristic peak nearby.

[0141] S4: In the dark environment, 15 g of photosensitive tertiary amine (dimethylaminoethyl methacrylate) was added dropwise to the negative photosensitive polyimide resin, and after the addition was completed, it was stirred at room temperature for 8-10 h to introduce the photosensitive tertiary amine onto the carboxyl group of the polyamic acid through ionic bond cooperation to obtain a negative photosensitive polyimide photoresist resin R1.

[0142] Example 2: Synthesis of negative photosensitive polyimide photoresist resin R2

[0143] The synthesis method of the negative photosensitive polyimide photoresist resin R2 of this example is basically the same as that of Example 1, the difference is that the diamine monomer used in step S1 is 2,2'-bis(trifluoromethyl)-4,4'-diaminophenyl ether, and the dianhydride monomer is 3,3',4,4'-biphenyl tetracarboxylic dianhydride.

[0144] Example 3: Synthesis of negative photosensitive polyimide photoresist resin R3

[0145] The synthesis method of the negative photosensitive polyimide photoresist resin R3 of this example is basically the same as that of Example 1, the difference is that the polymerization reaction in step S1 is carried out at 0°C for 12 h.

[0146] Example 4: Synthesis of negative photosensitive polyimide photoresist resin R4

[0147] The synthesis method of the negative photosensitive polyimide photoresist resin R4 of this example is basically the same as that of Example 1, the difference is that the polymerization reaction in step S1 is carried out at -5°C for 8-10 h.

[0148] Example 5: Synthesis of negative photosensitive polyimide photoresist resin R5

[0149] The synthesis method of the negative photosensitive polyimide photoresist resin R5 of this example is basically the same as that of Example 1, the difference is that the amount of polyamic acid solid used in step S2 for the intermediate is 25 g, and the amount of organic solvent is 46 g, and other raw materials and process parameters remain unchanged.

[0150] Example 6: Synthesis of negative photosensitive polyimide photoresist resin R6

[0151] The synthesis method of the negative photosensitive polyimide photoresist resin R6 of this example is basically the same as that of Example 1, the difference is that the amount of photosensitive tertiary amine dimethylaminoethyl methacrylate in step S4 is 10 g.

[0152] Example 7: Synthesis of negative photosensitive polyimide photoresist resin R7

[0153] The synthesis method of the negative photosensitive polyimide photoresist resin R7 of the present example is basically the same as that of Example 1, except that the dehydrating agent in step S3 is dicyclohexyl carbodiimide.

[0154] Example 8: Synthesis of negative photosensitive polyimide photoresist resin R8

[0155] The synthesis method of the negative photosensitive polyimide photoresist resin R8 of the present example is basically the same as that of Example 1, except that the amount of the dehydrating agent in step S3 is 1.8 g.

[0156] Example 9: Synthesis of negative photosensitive polyimide photoresist resin R9

[0157] The synthesis method of the negative photosensitive polyimide photoresist resin R9 of the present example is basically the same as that of Example 1, except that the diamine monomer used in step S1 is 2,2-bis[4-(4-aminophenoxy)phenyl]propane, and the dianhydride monomer is 4,4'-oxybisphthalic anhydride.

[0158] Example 10: Synthesis of negative photosensitive polyimide photoresist resin R10

[0159] The synthesis method of the negative photosensitive polyimide photoresist resin R10 of the present example is basically the same as that of Example 1, except that the 4,4'-diamino diphenyl ether in step S1 is replaced with an equal amount of 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, and the dianhydride monomer is replaced with an equal amount of 3,3',4,4'-benzophenonetetracarboxylic dianhydride.

[0160] Example 11: Synthesis of negative photosensitive polyimide photoresist resin R11

[0161] The synthesis method of the negative photosensitive polyimide photoresist resin R11 of the present example is basically the same as that of Example 1, except that the 2,2-bis(4-hydroxy-3-aminophenyl)propane in step S1 is replaced with an equal amount of 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene, and the hexafluoro dianhydride is replaced with an equal amount of 3,3',4,4'-biphenyltetracarboxylic dianhydride.

[0162] Example 12: Synthesis of negative photosensitive polyimide photoresist resin R12

[0163] The synthesis method of the negative photosensitive polyimide photoresist resin R12 of the present example is basically the same as that of Example 1, except that the diamine monomer used in step S1 is 4,4'-bis(4-aminophenoxy)biphenyl, and the dianhydride monomer is 2,3,3',4'-diphenyl ether tetracarboxylic dianhydride.

[0164] Example 13: Synthesis of negative photosensitive polyimide photoresist resin R13

[0165] The synthesis method of the negative photosensitive polyimide photoresist resin R13 of the present embodiment is basically the same as that of Embodiment 1, except that the diamine monomer used in step S1 is 4,4'-bis(3-aminophenoxy)diphenyl sulfone, and the dianhydride monomer is 3,3,4,4-diphenyl sulfone tetracarboxylic dianhydride.

[0166] Example 14: Synthesis of negative photosensitive polyimide photoresist resin R14

[0167] The synthesis method of the negative photosensitive polyimide photoresist resin R14 of the present embodiment is basically the same as that of Embodiment 1, except that the diamine monomer used in step S1 is 4,4'-bis(3-aminophenoxy)diphenyl sulfone, and the dianhydride monomer is 3,3,4,4-diphenyl sulfone tetracarboxylic dianhydride.

[0168] Comparative Example 1: Synthesis of negative photosensitive polyimide photoresist resin R15

[0169] The synthesis method of the negative photosensitive polyimide photoresist resin R15 of the present embodiment is basically the same as that of Embodiment 1, except that the 4,4'-diamino diphenyl ether in step S1 is modified to 2,2'-bis(trifluoromethyl)-4,4'-diamino phenyl ether.

[0170] Comparative Example 2: Synthesis of negative photosensitive polyimide photoresist resin R16

[0171] The synthesis method of the negative photosensitive polyimide photoresist resin R16 of the present embodiment is basically the same as that of Embodiment 1, except that the addition method of dimethylaminoethyl methacrylate in the fourth step of the synthesis of the negative photosensitive polyimide photoresist resin is modified from dropwise addition to pouring.

[0172] Comparative Example 3: Synthesis of negative photosensitive polyimide photoresist resin R17

[0173] The synthesis method of the negative photosensitive polyimide photoresist resin R17 of the present embodiment is basically the same as that of Embodiment 1, except that the dehydrating agent in the third step of the synthesis of the negative photosensitive polyimide photoresist resin is modified to triethylamine.

[0174] Comparative Example 4: Synthesis of negative photosensitive polyimide photoresist resin R18

[0175] The synthesis method of the negative photosensitive polyimide photoresist resin R18 of the present embodiment is basically the same as that of Embodiment 1, except that the amount of polyamic acid solid in step S2 of the synthesis of the negative photosensitive polyimide photoresist resin is modified to 20 g.

[0176] Comparative Example 5: Synthesis of negative photosensitive polyimide photoresist resin R19

[0177] The synthesis method of the negative photosensitive polyimide photoresist resin R19 of this example is basically the same as that of Example 1, except that the amount of the dehydrating agent in step S3 is 1 g.

[0178] Comparative Example 6: Synthesis of negative photosensitive polyimide photoresist resin R20

[0179] The synthesis method of the negative photosensitive polyimide photoresist resin R20 of this example is basically the same as that of Example 1, except that the amount of the photosensitive tertiary amine dimethylaminoethyl methacrylate in step S4 is 20 g.

[0180] Comparative Example 7: Synthesis of negative photosensitive polyimide photoresist resin R21

[0181] The synthesis method of the negative photosensitive polyimide photoresist resin R21 of this example is basically the same as that of Example 1, except that the conditions of the polymerization reaction in step S1 are 30°C for 8 h.

[0182] For the sake of clarity, the diamine monomers and dianhydride monomers of some examples and comparative examples are listed in Table 1, and the synthesis parameters of the negative photosensitive polyimide photoresist resins of some examples and comparative examples are listed in Tables 2 and 3.

[0183] Table 1: Monomers for synthesis of negative photosensitive polyimide photoresist resins

[0184]

[0185]

[0186]

[0187] Table 2: Synthesis parameters of negative photosensitive polyimide photoresist resins

[0188]

[0189]

[0190] Table 3: Synthesis parameters of negative photosensitive polyimide photoresist resins

[0191]

[0192]

[0193] Example 15: Formulation of negative photosensitive polyimide photoresist P1

[0194] A solution containing negative photosensitive polyimide photoresist resin R1 prepared in Example 1 (containing 30 g (30 wt%) of polyamic acid, 41 g (41 wt%) of solvent, 15 g (15 wt%) of photosensitive tertiary amine, 2.25 g (2.25 wt%) of dehydrating agent, and 3.375 g (3.375 wt%) of catalyst) was added with 3 g (3 wt%) of photosensitizer, 0.375 g (0.375 wt%) of crosslinking agent, and 5 g (5 wt%) of photoinitiator, and dissolved and mixed uniformly to obtain a negative photosensitive polyimide photoresist P1, wherein the photosensitizer is (michler's ketone), the crosslinking agent is (ethylene glycol diacrylate), and the photoinitiator is 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyl oxime) (OXE01).

[0195] Examples 16-28: Formulation of negative photosensitive polyimide photoresists P2-P14

[0196] The formulation method of the negative photosensitive polyimide photoresists P2-P14 is different from the formulation method of the negative photosensitive polyimide photoresist P1 in that the solution containing the negative photosensitive polyimide photoresist resin R1 prepared in Example 1 is modified to the solution containing the negative photosensitive polyimide photoresist resin R2-R14 prepared in any one of Examples 2-14.

[0197] Example 29: Formulation of negative photosensitive polyimide photoresist P22

[0198] The formulation method of the negative photosensitive polyimide photoresist P22 is different from the formulation method of the negative photosensitive polyimide photoresist P1 in that the crosslinking agent in Example 15 is changed to the same mass of hexafluoroacrylate, and other raw materials and process parameters remain unchanged.

[0199] Comparative Examples 8-14: Formulation of negative photosensitive polyimide photoresists P15-P21

[0200] The formulation method of the negative photosensitive polyimide photoresists P15-P21 is different from the formulation method of the negative photosensitive polyimide photoresist P1 in that the solution containing the negative photosensitive polyimide photoresist resin R1 prepared in Example 1 is modified to the solution containing the negative photosensitive polyimide photoresist resin R15-R21 prepared in any one of Comparative Examples 1-7.

[0201] Comparative Example 15: Formulation of negative photosensitive polyimide photoresist P23

[0202] The compounding method of the negative photosensitive polyimide photoresist P23 is different from the compounding method of the negative photosensitive polyimide photoresist PI in that no crosslinking agent is added in the compounding of the negative photosensitive polyimide photoresist, and other raw materials and process parameters remain unchanged.

[0203] Comparative Example 16: Compounding of negative photosensitive polyimide photoresist P24

[0204] The compounding method of the negative photosensitive polyimide photoresist P24 is different from the compounding method of the negative photosensitive polyimide photoresist PI in that no photosensitizer is added in the compounding of the negative photosensitive polyimide photoresist, and other raw materials and process parameters remain unchanged.

[0205] For the sake of clarity, the photoresist compounding parameters of some examples and comparative examples are listed in Table 4

[0206] Table 4: Compounding parameters of negative photosensitive polyimide photoresist

[0207]

[0208]

[0209] Example 23: Photoetching curing process and copper adhesion test

[0210] Photoetching development and curing

[0211] About 5g of a negative photosensitive polyimide photoresist selected from P1-P24 is dropped onto a 4-inch silicon wafer at a spin coating speed of 1800 rpm, and a hot plate is used for baking at 100°C for 180 seconds to remove most of the solvent. A profilometer is used to measure and ensure that the film thickness uniformity is within ±0.1 μm. Then a stepper photoetching machine is used for photoetching. After photoetching, a standard N-methyl pyrrolidone (NMP) developing solution is used for development at 25°C for 120 seconds. After development, the surface is rinsed clean with deionized water and nitrogen. A hot plate is used for baking at 110°C for 180 seconds to quickly cause crosslinking reaction on the film surface to prevent pattern flow. Curing is carried out in a nitrogen atmosphere in an oven, and the temperature curve is as follows: 50°C to 110°C (heating rate 2°C / min), 110°C for 30 min, 110°C to 180°C (heating rate 2°C / min), 180°C for 60 min, 180°C to 80°C (cooling rate 1°C / min), and finally 80°C to 40°C (cooling rate 1°C / min). Curing is completed.

[0212] The infrared absorption spectrum of the photoresist film after curing of the photoresist PI prepared in Example 15 is measured, and the results are shown in Figure 2 .

[0213] Copper adhesion test

[0214] A 5g of a negative photosensitive polyimide photoresist selected from one of P1-P24 was dropped on a 4 inch silicon wafer after copper plating treatment by physical vapor deposition (PVD) and spin-coated at a spin speed of 1800 rpm, followed by baking at 110°C for 180 seconds using a hot plate to remove most of the solvent, and curing in an oven under nitrogen atmosphere with the following temperature profile: 50°C to 110°C (ramp rate 2°C / min), hold for 30 min, then 110°C to 180°C (ramp rate 2°C / min), hold for 60 min, 120°C to 80°C (ramp rate 1°C / min), and finally 80°C to 40°C (ramp rate 1°C / min). The cured photoresist surface was plated with copper by PVD. The spin-coating and pre-baking steps were repeated once, and the cooled silicon wafer was placed in a stepper photolithography machine. The exposed silicon wafer was developed using standard N-methyl pyrrolidone (NMP) developer at 25°C for 120 seconds. The developed silicon wafer was placed in 5% sulfuric acid for 10 seconds, rinsed with water, and dried with nitrogen. The silicon wafer was then electroplated with copper for 10 minutes at a current density of 1. The electroplated silicon wafer was washed and dried, and then soaked in a photoresist stripper (NMP) until the surface photoresist was completely removed. The stripped silicon wafer was washed and dried, and then a transparent tape was applied to the electroplated pattern and the tape was immediately peeled off. The ratio of the number of patterns that were peeled off to the total number of patterns was the peeling rate.

[0215] The x and n values of the polymer resins in the photoresists of some examples and comparative examples are shown in Table 5 below:

[0216] Table 5: x and n values of polymer resins in some photoresists

[0217] Examples / Comparative Examples x n Example 15 (resist P1) 0.83 756 Example 16 (resist P2) 0.86 833 Example 17 (resist P3) 0.79 933 Example 18 (resist P4) 0.78 644 Example 19 (resist P5) 0.82 745 Example 20 (resist P6) 0.88 762 Example 21 (resist P7) 0.91 815 Example 22 (resist P8) 0.82 679 Example 23 (resist P9) 0.82 390 Example 24 (resist P10) 0.85 613 Example 25 (resist P11) 0.81 1230 Example 29 (resist P22) 0.81 548 Comparative Example 8 (resist P15) 0.76 774 Comparative Example 9 (resist P16) 0.60 879 Comparative Example 10 (resist P17) 0.63 792 Comparative Example 11 (resist P18) 0.93 771 Comparative Example 12 (resist P19) 0.41 445 Comparative Example 13 (resist P20) 0.33 537 Comparative Example 14 (resist P21) 0.63 390 Comparative Example 15 (resist P23) 0.98 758

[0218] The results of the lithography curing process and copper adhesion test and the corresponding analysis are as follows:

[0219] The photoresists P1-P7 all showed clear and complete patterns after lithography and curing at 180°C, with film thickness controlled at 1-10 μm, minimum line width stabilized at about 5 μm, peeling rate of 5-25 μm patterns less than 15%, peeling rate of 25-160 μm patterns less than 0.7%, and no embrittlement of the photoresist film after the lithography curing process.

[0220] The photoresist P8 produced a small amount of cracks after exposure, and the stability of the negative photoresist was slightly reduced.

[0221] Example 9 has a significantly increased viscosity of polyamic acid compared to Example 1. During the preparation of photoresist P9, a slight cracking phenomenon occurred due to stress during post-baking.

[0222] Photoresist P10 can form a pattern after alignment exposure, and the pattern is clearer after development, but the development speed is slightly faster.

[0223] Photoresist P11 has a slightly low sensitivity and precision after exposure and development.

[0224] Photoresist P22 has a complete and clear lithography pattern, which can be completely developed within 1 minute.

[0225] In Comparative Example 1, the viscosity of the 30% solution is large when the polyamic acid solid is redissolved, and the solution becomes a green gel after the mixed solution of dehydrating agent and catalyst is added, which affects the processing performance of the photoresist. After the photoresist curing process, the film thickness decreases. Therefore, the photoresist P15 obtained in Comparative Example 8 has an affected stability in subsequent processes compared to any one of photoresists P1-P7.

[0226] In Comparative Example 2, the viscosity of the solution increases sharply after pouring dimethylaminoethyl methacrylate, and the solution becomes a white turbid agglomerate with poor uniformity, which results in that the photoresist P16 obtained in Comparative Example 9 cannot be used for photoresist.

[0227] The photoresist P17 obtained in Comparative Example 10 has a significantly decreased contrast after curing compared to any one of photoresists P1-P7, and cannot form a clear and complete pattern.

[0228] The photoresist P18 obtained in Comparative Example 11 has a too small film thickness after the photoresist curing process compared to any one of photoresists P1-P7, which is only about 0.8 μm.

[0229] The photoresist P19 obtained in Comparative Example 12 is rapidly dissolved in the developing solution in the exposed area and the non-exposed area, and cannot form a pattern.

[0230] In Comparative Example 6, the solution first has an increased viscosity and becomes a gel-like state during the addition of photosensitive tertiary amine, and then becomes a clear and flowing state, which results in that the photoresist P20 obtained in Comparative Example 13 has a poor contrast and unclear pattern after photoresist.

[0231] The photoresist P21 obtained in Comparative Example 14 has a low contrast after development, and the thickness difference between the exposed area and the non-exposed area is too low.

[0232] The photoresist P23 obtained in Comparative Example 15 has a significantly decreased mechanical property of the photoresist film after the photoresist curing process, and has a brittle phenomenon. The development rate in the developing solution is too fast to be controlled, and a large number of cracks are generated in the pattern after the photoresist curing process.

[0233] In conclusion, the negative photosensitive polyimide photoresist has excellent low-temperature curing characteristics and adhesion to copper, and better meets the application requirements of semiconductor packaging materials.

[0234] The above embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent transformation or modification made according to the spirit and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A negatively photosensitive polyimide resin, characterized in that, The negatively photosensitive polyimide resin has the structure shown in Formula I: Ar1 is a tetravalent group containing two benzene rings; Ar2 is a divalent group containing two or more benzene rings and one or more ether bonds; R is selected from x=(S 1659 / S 1500 ) T / (S 1659 / S 1500 ) T’ x ranges from 0.78 to 0.91; Among them (S) 1659 / S 1500 ) T The infrared spectrum of the negative photosensitive polyimide resin at 1659 cm⁻¹ -1 The characteristic peak area at 1500 cm⁻¹ -1 The ratio of the characteristic peak area at (S) 1659 / S 1500 ) T’ The infrared spectrum of the polymer after treatment with dehydrating agent and catalyst is at 1659 cm⁻¹. -1 The characteristic peak area at 1500 cm⁻¹ -1 The ratio of the characteristic peak area at each location; n = Mw / Mr, where n is 300 to 1300; Where Mw is the weight-average molecular weight of the polymer obtained by permeation gel chromatography, and Mr is the relative molecular mass of the repeating unit of the polymer.

2. The negative photosensitive polyimide resin as described in claim 1, characterized in that, Ar1 is selected from one or more of the following groups:

3. The negative photosensitive polyimide resin as described in claim 1, characterized in that, Ar2 is selected from one or more of the following:

4. The negative photosensitive polyimide resin as described in claim 1, characterized in that, Ar1 is selected from one or more of the following groups: Furthermore, Ar2 is selected from one or more of the following groups:

5. A method for preparing a negatively photosensitive polyimide resin as described in any one of claims 1-4, characterized in that... Includes the following steps: (1) Dissolve the diamine monomer in an organic solvent, add the dianhydride monomer, and carry out the polymerization reaction at -5℃~10℃ for 8~14h to obtain polyamic acid liquid; (2) The polyamic acid liquid is washed and dried to obtain polyamic acid solid; the polyamic acid solid is dissolved in an organic solvent to obtain an intermediate, wherein the mass of polyamic acid in the intermediate is 10wt% to 50wt% of the total mass of the intermediate; (3) Add a dehydrating agent and a catalyst to the intermediate and stir at room temperature for 4 to 10 hours to carry out a dehydration imidization reaction to obtain negative photosensitive polyimide resin X; (4) Add a photosensitive tertiary amine to the negative photosensitive polyimide resin and stir at room temperature for 6 to 12 hours to obtain negative photosensitive polyimide resin Y. The structure of the dianhydride monomer is as follows: The structure of the diamine monomer is H2N-Ar2-NH2; The unit structure of negative photosensitive polyimide resin X is shown in formula (II); The unit structure of negative photosensitive polyimide resin Y is shown in formula (Ⅰ), wherein the proportion of the unit structure shown in formula (Ⅱ) in Y is x, and the proportion of the unit structure shown in formula (Ⅲ) in Y is (1-x). R is selected from 6. The method as described in claim 5, characterized in that, In step (1), the molar ratio of the dianhydride monomer to the diamine monomer is (1.01~1.1):1; In steps (1) and (2), the organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, γ-butyrolactone, N-methylpyrrolidone, ethyl lactate, butyl lactate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether and diethylene glycol diethyl ether, propylene glycol monomethyl ether, and isopropanol; In step (3), the dehydrating agent is selected from one or more of acetic anhydride, maleic anhydride, trifluoroacetic anhydride and N,N'-dicyclohexylcarbodiimide; the catalyst is selected from one or more of triethylamine, pyridine, diethylethanolamine, quinoline and isoquinoline; and the reaction temperature is 0 to 30°C.

7. The method as described in claim 5, characterized in that, In step (4), the mass ratio of the photosensitive tertiary amine to the solid polyamic acid in the intermediate is 1:(1~2.5); the reaction temperature is 0℃~30℃; the photosensitive tertiary amine is selected from one or more of N-methyldiethanolamine, N-ethyldiethanolamine, N-methyl-4-aminobenzoate, dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate.

8. A negative photosensitive polyimide photoresist composition, characterized in that, The photoresist composition comprises the negative photosensitive polyimide resin Y according to any one of claims 1-4, and further comprises an organic solvent, a crosslinking agent, a photosensitizer, and a photoinitiator; Based on the total mass of the negative photosensitive polyimide photoresist composition, the negative photosensitive polyimide resin Y content in the photoresist composition is 10wt%-50wt%, the organic solvent content is 40wt%-85wt%, the crosslinking agent content is 0.1wt%-5wt%, the photosensitizer content is 1wt%-10wt%, and the photoinitiator content is 1wt%-10wt%.

9. The negative photosensitive polyimide photoresist composition as described in claim 8, characterized in that, The organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, γ-butyrolactone, N-methylpyrrolidone, ethyl lactate, butyl lactate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether and diethylene glycol diethyl ether, propylene glycol monomethyl ether, and isopropanol. The crosslinking agent is a compound having a methacrylic acid structure or an acrylic acid structure, selected from one or more of glycidyl methacrylate, trivinyl methacrylate, polyethylene glycol dimethacrylate, ethylene glycol diacrylate, and hexafluoroacrylate; The photosensitizer is a compound having a benzophenone structure, selected from one or more of benzophenone, 4,4'-diaminobenzophenone, and (dimethylamino)benzophenone compounds; The photoinitiator is a compound containing a benzophenone structure / imidazolium structure / oxime ester structure, selected from one or more of 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, and 1-[4-(phenylthio)phenyl]-1,2-octanedione-2-(O-benzoyl oxime).

10. The application of the negative photosensitive polyimide photoresist composition as described in claim 8 or 9 in semiconductor packaging.

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