High-temperature-resistant polyimide photoresist, preparation method and application thereof

Abstract

The application relates to a high-temperature-resistant polyimide photoresist and a preparation method and application thereof, and the polyimide photoresist comprises the following raw material components in percentage by mass: a photoinitiator 0-5%, polyamic acid with a photosensitive group 30-60%, a leveling agent 0-1%, a crosslinking agent 5-10%, an adhesion promoter 0-1%, a solvent 50-90%, wherein the photosensitive group in the polyamic acid with the photosensitive group is at least one of a photodimerization type photosensitive group, a diazo or azido photosensitive group and an acrylate group. The high-temperature-resistant polyimide photoresist of the application can realize pattern formation without the aid of other photoresists, not only saves material cost, but also significantly shortens a process flow, improves a yield, and can realize high-resolution pattern production and protection of a substrate material simultaneously.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photoresist and particularly relates to a high-temperature-resistant polyimide photoresist as well as a preparation method and application thereof. BACKGROUND

[0002] In the field of liquid crystal display and semiconductor manufacturing, photoresist is a key functional material for realizing the transfer of patterns from a mask plate to a substrate. The application process is as follows: first, the photoresist is coated on the substrate (generally by spin coating), then pre-baking is performed to remove the solvent in the photoresist, then a specific wavelength of light source is used to irradiate the photoresist through the mask plate, the exposed area is chemically reacted to change its dissolution rate in the developing solution, then the corresponding pattern is obtained through development, then the pattern is transferred to the substrate without photoresist protection through etching, ion implantation or metal deposition process steps, and finally the photoresist is removed by a stripping solution to complete the pattern transfer process.

[0003] Generally, according to the different chemical action mechanisms, photoresist can be divided into two categories: positive photoresist and negative photoresist. The positive photoresist refers to the unexposed photoresist which is insoluble in the developing solution and can protect the underlying substrate material from the next process, while the exposed part of the photoresist film can be dissolved in the developing solution to expose the underlying substrate material for processing. The negative photoresist forms a film, the unexposed part can be washed away in the developing solution, and the exposed part becomes insoluble in the developing solution and remains on the substrate.

[0004] Polyimide is a polymer material with excellent heat resistance, mechanical properties, electrical insulation properties and chemical stability, and is one of the most important electronic chemical materials in the fields of aerospace, semiconductors, optoelectronics and microelectronics, and is widely used as interlayer insulation, surface passivation, stress buffer, radiation shielding and other materials.

[0005] The prior art generally uses traditional photoresist to realize patterns, and then applies polyimide protective glue. However, the prior art needs to do multi-layer coating in the process, and etches patterns on the polyimide protective glue, which has a complex process flow and high cost. Therefore, a photoresist containing photosensitive polyimide is needed, which can realize the production of high-resolution patterns and the protection of the substrate material after coating, exposure, development and curing, greatly shortening the process flow, saving cost and improving the yield. SUMMARY

[0006] The purpose of the present application is to provide a high-temperature-resistant polyimide photoresist which can realize pattern formation without the aid of other photoresists, not only saving material cost, but also significantly shortening the process flow and improving the yield, and can realize the production of high-resolution patterns and the protection of the substrate material at the same time.

[0007] The technical scheme adopted by the present application to solve the above problems is as follows: a high-temperature-resistant polyimide photoresist, by mass percentage, comprises the following raw material components:

[0008] Photoinitiator 0-5%

[0009] Polyamide acid with photosensitive groups 30%-60%

[0010] Leveling agent 0-1%

[0011] Crosslinking agent 5-10%

[0012] Tackifier 0-1%

[0013] Solvent 50%-90%

[0014] Preferably, the photosensitive groups in the polyamide acid with photosensitive groups are at least one of photodimerization type photosensitive groups, diazo or azido photosensitive groups, and acrylate groups.

[0015] Preferably, the photoinitiator is at least one of 2,2-diethoxyacetophenone, dimethyl anthranilate (DMPA), diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, bis (2,4,6-trimethylbenzoyl) phenyl phosphine oxide, 4,4'-dihydroxybenzophenone, and tris (4-tert-butylphenyl) sulfonium trifluoromethanesulfonate.

[0016] Preferably, the leveling agent is at least one of methyl trialkyl (C8-C10) ammonium chloride, 2,5-dimethyl-3-hexyne-2,5-diol, polyether-modified silicone oil, epoxy-modified silicone oil, and amino-modified silicone oil.

[0017] Preferably, the crosslinking agent is at least one of 1,2,4-benzene trianhydride (TMA), 6-maleimide butyric acid, tris (isopropenyl) vinyl silane, phenyl tris (dimethyl siloxy) silane, trimethylolpropane triacrylate, and trimethylolpropane trimethacrylate.

[0018] Preferably, the tackifier is an epoxy resin.

[0019] Preferably, the solvent is at least one of propylene glycol monomethyl ether acetate, ethyl lactate, ethyl acetate, butyl acetate, cyclohexanone, propylene glycol monomethyl ether, acetylacetone, N-methylpyrrolidone, diethylene glycol monomethyl ether, and diethylene glycol dimethyl ether.

[0020] Another object of the present application is to provide a preparation method of the high-temperature-resistant polyimide photoresist, which comprises mixing the components of the high-temperature-resistant polyimide photoresist above and filtering to obtain the high-temperature-resistant polyimide photoresist.

[0021] Another object of the present application is to provide an application of the high-temperature-resistant polyimide photoresist, comprising the following steps:

[0022] (1) applying the high-temperature-resistant polyimide photoresist on a substrate to form a photoresist coating;

[0023] (2) baking the photoresist coating obtained in step (1);

[0024] (3) exposing the photoresist coating baked in step (2) in a photoetching machine;

[0025] (4) developing the exposed photoresist coating in step (3) in a developing solution;

[0026] (5) heat-curing the developed photoresist coating in step (4);

[0027] Preferably, the thickness of the photoresist coating in step (1) is 5-50 um, the baking in step (2) is specifically baking at 90-150°C for 200s, and the heat-curing in step (5) is specifically baking at 300-400°C for 60 min.

[0028] Preferably, the exposure in step (3) is performed under full-spectrum exposure wavelength, and the developing solution in step (4) is a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution or cyclopentane, and the developing time is 20-80s.

[0029] Compared with the prior art, the present application has the following advantages:

[0030] The photoresist raw material of the present application contains polyamide acid with photosensitive groups, which has good light transmittance under ultraviolet light and better resolution. When applied in photoresist, the formation of patterns can be realized without the aid of other photoresists, which not only saves material cost, but also significantly shortens the process flow, improves the yield, and can simultaneously realize the production of high-resolution patterns and the protection of the substrate material. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 The figure is a schematic diagram of the synthesis of polyimide photoresist precursor and the photoetching process flow in the embodiments of the present application. DETAILED DESCRIPTION

[0032] The present application will be further described in detail below with reference to the embodiments of the drawings.

[0033] Example 1

[0034] A kind of high-temperature-resistant polyimide photoresist, comprising 25g polyamide acid with photosensitive group, 5g diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, 0.1g polyether modified silicone oil, 10g trimethylolpropane triacrylate, 0.3g epoxy resin and 70g N-methylpyrrolidone, the above-mentioned substances are mixed and fully stirred to completely dissolve, filtered through 0.2um polytetrafluoroethylene microporous filter membrane, and high-temperature-resistant polyimide photoresist is obtained.

[0035] The preparation method of the polyamide acid with photosensitive group is specifically as follows:

[0036] (1) 45g 4,4'-diamino diphenyl ether (ODA) is added to a four-necked flask containing 300g N-methylpyrrolidone, and ODA solution is obtained after complete dissolution; 65.5g pyromellitic dianhydride (PMDA) powder is slowly added to the ODA solution at a temperature of 30℃, and polyamide acid solution is obtained after complete dissolution, and then 200g N-methylpyrrolidone is added, and the reaction temperature (30℃) is maintained for 2h.

[0037] (2) 150g N,N-dimethylaminoethyl methacrylate (CAS: 2867-47-2) and 0.1g polymerization inhibitor hydroquinone are added to the polyamide acid solution, heated to 60℃, and stirred for 18h to obtain photosensitive polyamide acid;

[0038] (3) The obtained photosensitive polyamide acid solution is added dropwise into 4000g ethanol while stirring vigorously, and the precipitate is collected by suction filtration and vacuum dried at room temperature to obtain powdery polyamide acid with photosensitive group.

[0039] The application of a kind of high-temperature-resistant polyimide photoresist comprises the following steps:

[0040] 1) The high-temperature-resistant polyimide photoresist is coated on the corresponding substrate to form a photoresist coating layer, and the thickness of the photoresist coating layer is 10um;

[0041] 2) The photoresist coating layer obtained in step 1) is baked at 120℃ for 200s;

[0042] 3) The photoresist coating layer baked in step 2) is exposed to full-spectrum exposure wavelength in a photoetching machine;

[0043] 4) The photoresist coating layer baked in step 3) is developed in a developing solution for 60s, wherein the developing solution is a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution.

[0044] 5) The exposed photoresist coating layer in step 4) is baked at 300℃ for 60min to obtain a cured photoresist coating layer.

[0045] Example 2

[0046] A high-temperature-resistant polyimide photoresist is prepared by mixing and fully stirring 25 g of polyamic acid with photosensitive groups (same as in Example 1), 5 g of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, 0.1 g of polyether-modified silicone oil, 10 g of trimethylolpropane triacrylate, 0.3 g of epoxy resin, and 70 g of N-methylpyrrolidone, and filtering through a 0.2-μm polytetrafluoroethylene microporous filter.

[0047] A high-temperature-resistant polyimide photoresist is prepared by mixing and fully stirring 25 g of polyamic acid with photosensitive groups (same as in Example 1), 5 g of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, 0.1 g of polyether-modified silicone oil, 10 g of trimethylolpropane triacrylate, 0.3 g of epoxy resin, and 70 g of N-methylpyrrolidone, and filtering through a 0.2-μm polytetrafluoroethylene microporous filter.

[0048] 1) The high-temperature-resistant polyimide photoresist is applied to a corresponding substrate to form a photoresist coating layer, and the thickness of the photoresist coating layer is 10 μm.

[0049] 2) The photoresist coating layer obtained in step 1) is baked at 120°C for 200 s.

[0050] 3) The photoresist coating layer after baking in step 2) is subjected to full-spectrum exposure wavelength exposure treatment in a photoetching machine.

[0051] 4) The photoresist coating layer after baking in step 3) is subjected to development in a developer for 60 s, wherein the developer is a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution.

[0052] 5) The photoresist coating layer after exposure in step 4) is baked at 325°C for 60 min to obtain a cured photoresist coating layer.

[0053] Example 3

[0054] A high-temperature-resistant polyimide photoresist is prepared by mixing and fully stirring 25 g of polyamic acid with photosensitive groups (same as in Example 1), 5 g of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, 0.1 g of polyether-modified silicone oil, 10 g of trimethylolpropane triacrylate, 0.3 g of epoxy resin, and 70 g of N-methylpyrrolidone, and filtering through a 0.2-μm polytetrafluoroethylene microporous filter.

[0055] A high-temperature-resistant polyimide photoresist is prepared by mixing and fully stirring 25 g of polyamic acid with photosensitive groups (same as in Example 1), 5 g of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, 0.1 g of polyether-modified silicone oil, 10 g of trimethylolpropane triacrylate, 0.3 g of epoxy resin, and 70 g of N-methylpyrrolidone, and filtering through a 0.2-μm polytetrafluoroethylene microporous filter.

[0056] 1) The high-temperature-resistant polyimide photoresist is applied to a corresponding substrate to form a photoresist coating layer, and the thickness of the photoresist coating layer is 10 μm.

[0057] 2) The photoresist coating layer obtained in step 1) is baked at 120°C for 200 s.

[0058] 3) The baked photoresist coating of step 2) is exposed to full spectrum exposure wavelength in a photoetch machine.

[0059] 4) The baked photoresist coating of step 3) is developed in a developer solution for 60 seconds, wherein the developer solution is a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH).

[0060] 5) The exposed photoresist coating of step 4) is baked at 350°C for 60 minutes to obtain a cured photoresist coating.

[0061] Comparative Example 1

[0062] A high temperature resistant polyimide photoresist is prepared by mixing and thoroughly stirring 25g of polyamide acid with photosensitive groups (same as in Example 1), 5g of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, 0.1g of polyether modified silicone oil, 10g of trimethylolpropane triacrylate, 0.3g of epoxy resin, and 70g of N-methylpyrrolidone, and filtering through a 0.2um polytetrafluoroethylene micro-porous filter.

[0063] A high temperature resistant polyimide photoresist is prepared by mixing and thoroughly stirring 25g of polyamide acid with photosensitive groups (same as in Example 1), 5g of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, 0.1g of polyether modified silicone oil, 10g of trimethylolpropane triacrylate, 0.3g of epoxy resin, and 70g of N-methylpyrrolidone, and filtering through a 0.2um polytetrafluoroethylene micro-porous filter.

[0064] 1) The high temperature resistant polyimide photoresist is coated on a corresponding substrate to form a photoresist coating, and the thickness of the photoresist coating is 10um.

[0065] 2) The photoresist coating obtained in step 1) is baked at 120°C for 200 seconds.

[0066] 3) The baked photoresist coating of step 2) is exposed to full spectrum exposure wavelength in a photoetch machine.

[0067] 4) The baked photoresist coating of step 3) is developed in a developer solution for 60 seconds, wherein the developer solution is a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH).

[0068] 5) The exposed photoresist coating of step 4) is baked at 275°C for 60 minutes to obtain a cured photoresist coating.

[0069] The cured photoresist coatings obtained in Examples 1-3 and Comparative Example 1 are subjected to heat resistance and etch resistance experiments, as follows:

[0070] Heat resistance: The cured photoresist coating of step 5) is baked at 425°C for 60 minutes, and the pattern integrity is observed under a microscope.

[0071] Etch resistance: the photoresist coating after curing in step 5) was etched in a copper plating solution at 25°C for 60 min, and the pattern integrity was observed under a microscope.

[0072] The test results are shown in the following table:

[0073] Curing temperature (°C) Film thickness (um) Heat resistance Etch resistance Comparative Example 1 275 10 Pattern complete Pattern incomplete Example 1 300 10 Pattern complete Pattern complete Example 2 325 10 Pattern complete Pattern complete Example 3 350 10 Pattern complete Pattern complete

[0074] From the above results, it can be seen that the polyimide photoresist according to the present application can ensure the integrity of the pattern under high temperature curing; when the curing temperature reaches above 300°C, it also has excellent etch resistance in the plating solution, and the formed polyimide layer can provide good protection for the substrate, so as to facilitate the processing of the post-process technology, and is suitable for the fields of integrated circuits, flat panel displays, and semiconductor wafer level packaging, etc.

[0075] In addition to the above embodiments, the present application also includes other implementation manners, and any technical solutions formed by equivalent transformation or equivalent replacement shall fall within the protection scope of the claims of the present application.

Claims

1. A high temperature resistant polyimide photoresist, characterized by: By mass percent, the following raw material components are included: Photoinitiator 0-5% Polyamic acid with photosensitive group 30%-60% Leveling agent 0-1% Crosslinking agent 5-10% Tackifier 0-1% Solvent 50%-90% The preparation method of the polyamic acid with photosensitive group is specifically as follows: (1) 45g of 4,4'-diamino diphenyl ether (ODA) is added to a four-necked flask containing 300g of N-methyl pyrrolidone, and after complete dissolution, an ODA solution is obtained; at a temperature of 30°C, 65.5g of phthalic anhydride (PMDA) powder is slowly added to the ODA solution, and after complete dissolution, 200g of N-methyl pyrrolidone is added, and the reaction temperature is maintained at 30°C for 2h to obtain a polyamic acid solution; (2) 150g of N,N-dimethylaminoethyl methacrylate (CAS: 2867-47-2) and 0.1g of the polymerization inhibitor hydroquinone are added to the polyamic acid solution, heated to 60°C, and stirred for 18h to obtain a photosensitive polyamic acid; (3) The obtained photosensitive polyamic acid solution is added dropwise to 4000g of ethanol while stirring vigorously, the precipitate is collected by suction filtration, and vacuum drying is performed at room temperature to obtain a powdery polyamic acid with photosensitive group.

2. The high temperature resistant polyimide photoresist according to claim 1, wherein: The photoinitiator is at least one of 2,2-diethoxyacetophenone, benzoin dimethyl ether DMPA, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, bis (2,4,6-trimethylbenzoyl) phenyl phosphine oxide, 4,4'-dihydroxybenzophenone, and tris (4-tert-butylphenyl) sulfonium trifluoromethanesulfonate.

3. The high temperature resistant polyimide photoresist according to claim 1, wherein: The leveling agent is at least one of methyl trialkyl (C8-C10) ammonium chloride, 2,5-dimethyl-3-hexyne-2,5-diol, polyether modified silicone oil, epoxy modified silicone oil, and amino modified silicone oil.

4. The high temperature resistant polyimide photoresist according to claim 1, wherein: The crosslinking agent is at least one of 1,2,4-benzene trianhydride (TMA), 6-maleimide butyric acid, tris (isopropenyl) vinyl silane, phenyl tris (dimethyl siloxy) silane, trimethylolpropane triacrylate, and trimethylolpropane trimethacrylate; and the tackifier is an epoxy resin.

5. The high temperature resistant polyimide photoresist according to claim 1, wherein: The tackifier is an epoxy resin.

6. The high temperature resistant polyimide photoresist according to claim 1, wherein: The solvent is at least one of propylene glycol monomethyl ether acetate, ethyl lactate, ethyl acetate, butyl acetate, cyclohexanone, propylene glycol monomethyl ether, acetylacetone, N-methyl pyrrolidone, diethylene glycol monomethyl ether, and diethylene glycol dimethyl ether.

7. A method for preparing the high-temperature-resistant polyimide photoresist according to any one of claims 1-6, characterized in that: The high-temperature-resistant polyimide photoresist is obtained by mixing the components of the high-temperature-resistant polyimide photoresist in proportion and filtering.

8. Use of the high-temperature resistant polyimide photoresist according to any one of claims 1-6, characterized in that: The method comprises the following steps: (1) The high-temperature-resistant polyimide photoresist is coated on a substrate to form a photoresist coating layer; (2) The photoresist coating layer obtained in step (1) is baked; (3) The baked photoresist coating layer in step (2) is exposed to light in a photoetching machine; (4) The exposed photoresist coating layer in step (3) is developed in a developing solution; (5) The developed photoresist coating layer in step (4) is heated and cured.

9. The method for preparing the high-temperature resistant polyimide photoresist according to claim 8, characterized in that: The thickness of the photoresist coating in step (1) is 5-50 um, and the baking in step (2) is specifically baking at 90-150 ℃ for 200 s; the heating and curing in step (5) is specifically baking at 300-400 ℃ for 60 min.

10. The method for preparing the high-temperature resistant polyimide photoresist according to claim 8, characterized in that: The exposure in step (3) is performed under full-spectrum exposure wavelength; and the developing solution in step (4) is a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution or cyclopentane, and the developing time is 20-80 s.

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