Photoresist stripping liquid as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of photoresist, and particularly relates to photoresist stripping liquid as well as a preparation method and application thereof. The photoresist stripping liquid contains a first amine compound, a second amine compound and an organic solvent I, wherein the first amine compound has a structure as shown in a formula (1) or a formula (2); the second amine compound has a structure as shown in a formula (3). The key point of the invention lies in that the specific first amine compound and second amine compound are adopted as key components of the photoresist stripping liquid, and the obtained photoresist stripping liquid has strong photoresist removal capability and effect, can achieve basically no residue on a base material, and has the advantages of short treatment time, high efficiency, small corrosion to the base material, and low cost. And the substrate at the lower layer is hardly damaged. # imgabs0 #

Description

Technical Field

[0001] The invention belongs to the technical field of photoresists, and in particular relates to a photoresist stripping solution and a preparation method and application thereof. Background Art

[0002] Photoresist is a photosensitive material, a mixed liquid composed of three parts: photosensitive resin, photosensitizer and solvent. After being exposed to light, the photosensitive resin can quickly undergo a photocuring reaction in the exposed area, causing significant changes in the material properties of this material, especially its solubility. After being treated with appropriate solvents and dissolving the soluble part, the photoresist can form the required pattern. Photoresist is mainly used in the field of microelectronics. For example, in semiconductor devices, liquid crystal devices and integrated circuits, a series of steps such as coating and exposure of photoresist on a substrate are required to obtain the corresponding pattern. Then, the pattern is transferred to a substrate without photoresist protection through etching, ion implantation or metal precipitation. Finally, the unnecessary photoresist part is removed by photoresist stripping liquid, completing the process of transferring the pattern to be etched from the mask to the substrate.

[0003] As the structure of semiconductor chip materials becomes more and more complex, the environment faced by the photoresist stripping solution used in its manufacturing process is also becoming more and more complex. It is necessary to remove the photoresist without generating residues. At present, conventional photoresist stripping solution compositions often leave tiny stains or foreign matter on the film when stripping and removing the residual photoresist pattern on the substrate. Such tiny stains or foreign matter become the main reason for reducing the input-output ratio of subsequent processes. Traditional photoresist stripping solutions usually use strong alkaline materials, which can cause corrosion to copper or aluminum wires and substrates. The main method currently used is to add metal protective agents, such as benzotriazole, methylbenzotriazole, etc. as metal protective agents in Chinese patent application document CN115047732A, but adding metal protective agents will lead to an increase in cost; and although the photoresist stripping solution with weak alkalinity has little corrosiveness to the substrate, its photoresist stripping effect is poor, there is residue, or the processing time is long and the efficiency is low. In view of this, it is urgent to find a photoresist stripping solution that takes into account good photoresist stripping effect and weak corrosiveness. Summary of the invention

[0004] The purpose of the present invention is to provide a photoresist stripping solution and its preparation method and application in view of the shortcomings of existing photoresist stripping solutions that it is difficult to simultaneously achieve good photoresist stripping effects and weak corrosion to substrates. The photoresist stripping solution has good photoresist stripping effects, is basically free of residues, has a short processing time, is highly efficient, and has weak corrosion to substrates and causes little damage.

[0005] In a first aspect, the present invention provides a photoresist stripping solution, the photoresist stripping solution comprising a first amine compound, a second amine compound and an organic solvent I; the first amine compound has a structure as shown in formula (1) or formula (2); the second amine compound has a structure as shown in formula (3);

[0006]

[0007] In formula (1) and formula (2), Y is C 1 ~C 10 The alkyl group, L is C 1 ~C 4 ester bond, X is a single bond or C 1 ~C 20 Alkylene, R is a hydrogen atom or C 1 ~C 20 The alkyl group, R 1 and R 1 `Each independently is C 1 ~C 10 alkyl, n is an integer from 1 to 3; in formula (3), R 2 C 1 ~C 5 The alkylene group, R 3 and R 4 Each independently is C 1 ~C 5 Alkyl or C 1 ~C 5 of hydroxyalkyl.

[0008] In a preferred embodiment, the mass ratio of the first amine compound to the second amine compound is 1:(0.5-2).

[0009] In a preferred embodiment, based on the total mass of the photoresist stripping solution, the content of the first amine compound is 5-10 wt %, the content of the second amine compound is 5-10 wt %, and the content of the organic solvent is 85-90 wt %.

[0010] In a preferred embodiment, the first amine compound is prepared by the following method: Compound I having a structure represented by formula (4) and Compound II having a structure represented by formula (5) or formula (6) are subjected to a condensation reaction in the presence of a catalyst, and the obtained product is the first amine compound having a structure represented by formula (1);

[0011] R 6 —X—N—R 3-n Formula (5):

[0012]

[0013] In formula (4), Y is C 1 ~C 10 The alkyl group, R 5 C 0 ~C 3 In formula (5) and formula (6), R 6 is hydroxyl or halogen, X is a single bond or C 1 ~C 20 Alkylene, R is a hydrogen atom or C 1 ~C 20 The alkyl group, R 1 and R 1 `Each independently is C 1 ~C 10 wherein n is an integer of 1 to 3.

[0014] In a preferred embodiment, the molar ratio of compound I to compound II is 1:(0.8-1.2).

[0015] In a preferred embodiment, the amount of the catalyst used is 1 to 5 wt% of the sum of the mass of compound I and compound II.

[0016] In a preferred embodiment, the condensation reaction conditions include a temperature of 100 to 150° C. and a time of 10 to 15 hours.

[0017] In a preferred embodiment, the compound I is selected from at least one of p-toluic acid, p-ethylbenzoic acid, p-propylbenzoic acid, p-tolueneacetic acid, 4-isopropylphenylacetic acid, p-toluenepropionic acid, 4-ethylphenylpropionic acid, 2-(4-isopropylphenyl)propionic acid, 2-(3-isobutylphenyl)propionic acid, and 3-(4-isobutylphenyl)propionic acid.

[0018] In a preferred embodiment, the compound II is selected from at least one of diethylaminoethanol, dimethylaminoethanol, 3-diethylamino-1-propanol, 2-morpholinoethanol, 4-(3-hydroxypropyl)morpholine, and 1,5-oxazacyclooctanebutanol.

[0019] In a preferred embodiment, the catalyst is selected from at least one of dimethylaminopyridine, triethylamine, pyridine and diisopropylethylamine.

[0020] In a preferred embodiment, the condensation reaction is carried out in the presence of an organic solvent II.

[0021] In a preferred embodiment, the organic solvent II is selected from at least one of dichloromethane, tetrahydrofuran, dimethyl sulfoxide and dimethylformamide.

[0022] In a preferred embodiment, the second amine compound is selected from at least one of N,N-diethyl-1,3-propylenediamine, N,N-diisopropyl-1,3-propylenediamine and N-(2-hydroxyethyl)ethylenediamine.

[0023] In a preferred embodiment, the organic solvent I is selected from at least one of butyl acetate, N-ethylpyrrolidone, 4-methyl-2-pentanol, sulfolane, pyrrolidone and N-methylpyrrolidone.

[0024] In a second aspect, the present invention provides a method for preparing the above-mentioned photoresist stripping solution, the preparation method comprising: mixing a first amine compound, a second amine compound and an organic solvent to obtain the photoresist stripping solution.

[0025] In a third aspect, the present invention provides a method for stripping photoresist, which comprises the following steps: immersing a substrate from which the photoresist needs to be stripped in the above-mentioned photoresist stripping solution, and after the immersion is completed, rinsing the substrate with a rinsing solution to complete the stripping of the photoresist on the substrate.

[0026] In a preferred embodiment, the soaking conditions include: the temperature of the stripping solution is 50-70° C., and the soaking time is 10-15 minutes.

[0027] In a fourth aspect, the present invention further provides the use of the above-mentioned photoresist stripping solution or photoresist stripping method in a semiconductor substrate that requires photoresist stripping.

[0028] The key of the present invention is to use a specific first amine compound and a second amine compound as key components of a photoresist stripping solution, and then combine them with an organic solvent. The obtained photoresist stripping solution has a strong ability and effect to remove photoresist due to the synergistic effect of the first amine compound and the second amine compound, and can achieve basically no residue on the substrate, and the processing time is short and the efficiency is high. At the same time, the corrosion to the substrate is small, and almost no damage is caused to the underlying substrate. DETAILED DESCRIPTION

[0029] The photoresist stripping solution provided by the present invention contains a first amine compound, a second amine compound and an organic solvent I. The first amine compound has a structure as shown in formula (1) or formula (2). The second amine compound has a structure as shown in formula (3).

[0030]

[0031] In formula (1) and formula (2), the positions where Y and L are bonded to the benzene ring may be ortho, para or meta; Y is C 1 ~C 10 The alkyl group is preferably C 1 ~C5 L is C 1 ~C 4 ester bond; X is a single bond or C 1 ~C 20 The alkylene group is preferably C 1 ~C 5 An alkylene group; R is a hydrogen atom or C 1 ~C 20 An alkyl group is preferably a hydrogen atom or a C 1 ~C 10 An alkyl group is more preferably a hydrogen atom or a C 1 ~C 5 Alkyl; R 1 and R 1 `Each independently is C 1 ~C 10 The alkyl group is preferably C 1 ~C 5 alkyl; n is an integer of 1 to 3, such as 1, 2 or 3. In formula (3), R 2 C 1 ~C 5 The alkylene group, R 3 and R 4 Each independently is C 1 ~C 5 Alkyl or C 1 ~C 5 wherein said C 1 ~C 10 Specific examples of the alkyl group include, but are not limited to, at least one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-hexyl. 1 ~C 4 Specific examples of ester bonds include, but are not limited to: -COO-, -CH 2 COO-、-(CH 2 ) 2 COO-、-CHCH 3 COO-、-(CH 2 ) 3 COO-、-CHCH 3 CH 2 COO-、-CH 2 CHCH 3 At least one of COO-. 1 ~C 20 Specific examples of the alkylene group include, but are not limited to, at least one of methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, undecylene, and dodecylene.1 ~C 20 Specific examples of the alkyl group include, but are not limited to, at least one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, n-pentyl, isopentyl, neopentyl, hexyl, heptyl, octyl, undecyl, and dodecyl. 1 ~C 5 Specific examples of the alkylene group include, but are not limited to, at least one of methylene, ethylene, n-propylene, isopropylene, n-butylene, isobutylene, tert-butylene, sec-butylene, n-pentylene, isopentylene, and neopentylene. 1 ~C 5 Specific examples of the alkyl group include, but are not limited to, at least one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, n-pentyl, isopentyl, and neopentyl. 1 ~C 5 Specific examples of hydroxyalkyl include, but are not limited to: -CH 2 OH, -(CH 2 ) 2 OH, -(CH 2 ) 3 OH, -CH 2 CHCH 3 OH, -CHCH 3 CH 2 OH, -(CH 2 ) 4 OH, -CHCH 3 (CH 2 ) 2 OH, -(CHCH 3 ) 2 OH, -C(CH 3 ) 2 CH 2 OH, -CH 2 C(CH 3 ) 2 At least one of OH.

[0032] In the present invention, the mass ratio of the first amine compound to the second amine compound is preferably 1:(0.5-2), such as 1:0.5, 1:0.8, 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2 or any value therebetween. Controlling the mass ratio of the first amine compound to the second amine compound within the above preferred range is more conducive to the stripping of the photoresist, with substantially no residue, and has less corrosiveness to the substrate, and hardly causes damage to the underlying substrate. Based on the total mass of the photoresist stripping solution, the content of the first amine compound is preferably 5 to 10wt%, such as 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt% or any value therebetween; the content of the second amine compound is preferably 5 to 10wt%, such as 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt% or any value therebetween; the content of the organic solvent is preferably 85 to 90wt%, such as 85wt%, 86wt%, 87wt%, 88wt%, 89wt%, 90wt% or any value therebetween.

[0033] In the present invention, the first amine compound can be any compound having a structure shown in formula (1) or formula (2), and can be purchased or prepared by a chemical synthesis method. The first amine compound is preferably prepared by the following method: a compound I having a structure shown in formula (4) and a compound II having a structure shown in formula (5) or formula (6) are subjected to a condensation reaction in the presence of a catalyst, and the obtained product is the first amine compound having a structure shown in formula (1) or formula (2).

[0034] R 6 —X—N—R 3-n Formula (5)

[0035]

[0036] In formula (4), the positions where Y and L are bonded to the benzene ring may be ortho, para or meta; Y is C 1 ~C 10 The alkyl group is preferably C 1 ~C 5 Alkyl; R 5 C 0 ~C 3 In formula (5) and formula (6), R 6 is hydroxyl or halogen, X is a single bond or C 1 ~C 20 Alkylene, R is a hydrogen atom or C 1 ~C 20 An alkyl group is preferably a hydrogen atom or a C 1 ~C10 An alkyl group is more preferably a hydrogen atom or a C 1 ~C 5 Alkyl; R 1 and R 1 `Each independently is C 1 ~C 10 The alkyl group is preferably C 1 ~C 5 alkyl; n is an integer from 1 to 3, such as 1, 2 or 3. 0 ~C 3 Specific examples of the alkylene group include, but are not limited to: -, -CH 2 -、-(CH 2 ) 2 -、-CHCH 3 -、-(CH 2 ) 3 -、-CHCH 3 CH 2 -、-CH 2 CHCH 3 -At least one of. Specific examples of the remaining groups are as described above and will not be repeated here one by one.

[0037] In the present invention, the molar ratio of the compound I to the compound II is preferably 1:(0.8-1.2), such as 1:0.8, 1:0.9, 1:0.95, 1:1, 1:1.05, 1:1.1, 1:1.2 or any value therebetween. The amount of the catalyst is preferably 1-5wt% of the sum of the mass of the compound I and the compound II, such as 1wt%, 2wt%, 3wt%, 4wt%, 5wt% or any value therebetween.

[0038] In the present invention, the conditions of the condensation reaction may include a temperature preferably of 100 to 150°C, such as 100°C, 110°C, 120°C, 130°C, 140°C, 150°C or any value therebetween; and a time preferably of 10 to 15h, such as 10h, 11h, 12h, 13h, 14h, 15h or any value therebetween.

[0039] In the present invention, the compound I is a compound having a structure as shown in formula (4), and its specific examples include but are not limited to: at least one of p-toluic acid, p-ethylbenzoic acid, p-propylbenzoic acid, p-tolueneacetic acid, 4-isopropylphenylacetic acid, p-toluenepropionic acid, 4-ethylphenylpropionic acid, 2-(4-isopropylphenyl)propionic acid, 2-(3-isobutylphenyl)propionic acid, and 3-(4-isobutylphenyl)propionic acid.

[0040] In the present invention, the compound II is a compound having a structure as shown in formula (5) or formula (6), and its specific examples include but are not limited to: at least one of diethylaminoethanol, dimethylaminoethanol, 3-diethylamino-1-propanol, 2-morpholinoethanol, 4-(3-hydroxypropyl)morpholine, and 1,5-oxazacyclooctanebutanol.

[0041] In the present invention, the type and source of the catalyst are not specifically limited, as long as it can catalyze the condensation reaction of compound I and compound II to obtain the first amine compound having the structure represented by formula (1) or formula (2). The catalyst is preferably an organic amine catalyst, and specific examples thereof include but are not limited to at least one of dimethylaminopyridine, triethylamine, pyridine, and diisopropylethylamine.

[0042] In the present invention, the condensation reaction is preferably carried out in the presence of an organic solvent II. The organic solvent II can be a conventional choice in the art, and specific examples thereof include but are not limited to: at least one selected from dichloromethane, tetrahydrofuran, dimethyl sulfoxide, and dimethylformamide.

[0043] In a specific embodiment, the preparation method of the first amine compound can be as follows: in an inert gas atmosphere, compound I having a structure shown in formula (4), compound II having a structure shown in formula (5) or formula (6), a catalyst and an organic solvent II are mixed and reacted for 12 hours, the reaction is stopped, and an aqueous work-up is performed to separate the solvent and the product, and the obtained product is the first amine compound having a structure shown in formula (1) or formula (2). Wherein, the inert gas can be a conventional choice in the art, preferably nitrogen, argon. At least one of xenon and neon. The method of stopping the reaction can be cooling the reaction solution with an ice bath and / or adding a hydrochloric acid solution to stop the reaction. The concentration of the hydrochloric acid solution is preferably 0.5 to 1.5wt%, such as 0.5wt%, 0.8wt%, 1wt%, 1.2wt%, 1.5wt% or any value therebetween. The aqueous work-up can be a method for separating the product and the solvent known to those skilled in the art, and the present invention preferably uses a distillation method.

[0044] In the present invention, the second amine compound can be any compound having a structure as shown in formula (3), and specific examples thereof include but are not limited to at least one of N,N-diethyl-1,3-propylenediamine, N,N-diisopropyl-1,3-propylenediamine and N-(2-hydroxyethyl)ethylenediamine.

[0045] In the present invention, the organic solvent I can be a conventional choice in the art, and specific examples thereof include but are not limited to: at least one of butyl acetate, N-ethylpyrrolidone, 4-methyl-2-pentanol, cyclopentane sulfone, pyrrolidone, and N-methylpyrrolidone.

[0046] The preparation method of the photoresist stripping solution provided by the invention comprises: mixing a first amine compound, a second amine compound and an organic solvent to obtain the photoresist stripping solution.

[0047] The photoresist stripping method provided by the present invention comprises the following steps: immersing the substrate from which the photoresist needs to be stripped in the photoresist stripping solution, and after the immersion is completed, rinsing the substrate with a rinsing solution to complete the photoresist stripping on the substrate. The immersion conditions may include: the temperature of the stripping solution is preferably 50 to 70°C, such as 50°C, 55°C, 60°C, 65°C, 70°C or any value therebetween; the immersion time is preferably 10 to 15 minutes, such as 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes or any value therebetween.

[0048] The present invention provides the application of the photoresist stripping solution or the photoresist stripping method in a semiconductor substrate that has a need to strip photoresist. The photoresist stripping solution can be used to remove patterned photoresist films of various thicknesses. The photoresist can be various existing conventional photoresist materials.

[0049] The present invention will be described in detail below through specific embodiments.

[0050] Synthesis Example 1 Synthesis of the First Amine Compound

[0051] Under the protection of nitrogen, 13.62g of p-toluic acid (0.1mol), 12.89g of diethylaminoethanol (0.098mol), 1.00g of dimethylaminopyridine (3.77wt%), and 300mL of dichloromethane were mixed and stirred and reacted at 130°C for 12h, then the reaction solution was cooled in an ice bath, 20g of 1wt% hydrochloric acid aqueous solution was added to stop the reaction, and the solvent was distilled off by water treatment to obtain 17.18g of colorless oil, which was the first amine compound, denoted as A1, with a yield of 73%. Its synthesis route is shown below.

[0052]

[0053] Synthesis Example 2 Synthesis of the First Amine Compound

[0054] Under the protection of nitrogen, 16.42g of p-toluic acid (0.12mol), 14.42g of morpholine ethanol (0.11mol), 1.5g of dimethylaminopyridine (4.86wt%), and 350mL of dichloromethane were mixed and stirred and reacted at 130°C for 12h, then the reaction solution was cooled in an ice bath, and the reaction was stopped with 20g of 1wt% hydrochloric acid aqueous solution, and the solvent was distilled off by water treatment to obtain 18.59g of colorless oil, which is the first amine compound, denoted as A2, with a yield of 67%. Its synthetic route is shown below.

[0055]

[0056] Synthesis Example 3 Synthesis of the First Amine Compound

[0057] Under the protection of nitrogen, 17.82g of 4-ethylbenzenepropionic acid (0.1mol), 12.89g of diethylaminoethanol (0.098mol), 1.00g of dimethylaminopyridine (3.26wt%), and 300mL of dichloromethane were mixed and stirred and reacted at 130°C for 12h, then the reaction solution was cooled in an ice bath, 20g of 1wt% hydrochloric acid aqueous solution was added to stop the reaction, and the solvent was distilled off by water treatment to obtain 17.18g of colorless oil, which was the first amine compound, denoted as A1, with a yield of 73%. Its synthesis route is shown below.

[0058]

[0059] Synthesis Example 4 Synthesis of the First Amine Compound

[0060] Under the protection of nitrogen, 13.62g of p-toluic acid (0.1mol), 18.73g of 1,5-oxazacyclooctanol (0.1mol), 1.00g of dimethylaminopyridine (3.77wt%), and 300mL of dichloromethane were mixed and stirred and reacted at 130°C for 12h, then the reaction solution was cooled in an ice bath, 20g of 1wt% hydrochloric acid aqueous solution was added to stop the reaction, and the solvent was distilled off by water treatment to obtain 21.37g of colorless oil, which was the first amine compound, denoted as A4, with a yield of 70%. Its synthesis route is shown below.

[0061]

[0062] Example 1

[0063] Preparation of photoresist stripping solution: Take 5 g of the first amine compound A1, add 7.5 g of N,N-diethyl-1,3-propylenediamine and 87.5 g of butyl acetate, mix thoroughly and filter with a 0.1 μm filter element to obtain a photoresist stripping solution.

[0064] Photoresist stripping method: Place the photoresist stripping solution obtained in this embodiment into a stripping tank, then heat it to 70°C, place the substrate to be treated (made of copper) into the stripping solution in the stripping tank, keep the temperature constant for 10 minutes, take out the substrate, and then immerse it in isopropanol for 1 minute. After taking it out, rinse the substrate with a large amount of deionized water, and finally observe under a microscope: no photoresist residue on the surface of the treated substrate.

[0065] Example 2

[0066] Preparation of photoresist stripping solution: Take 5 g of the first amine compound A2, add 5 g of N,N-diethyl-1,3-propylenediamine and 90 g of butyl acetate, mix thoroughly and filter with a 0.1 μm filter element to obtain a photoresist stripping solution.

[0067] Photoresist stripping method: Place the photoresist stripping solution obtained in this embodiment into a stripping tank, then heat it to 60°C, place the substrate to be treated (made of copper) into the stripping solution in the stripping tank, keep the temperature constant for 10 minutes, take out the substrate, and then immerse it in isopropanol for 1 minute. After taking it out, rinse the substrate with a large amount of deionized water, and finally observe under a microscope: there is almost no photoresist residue on the surface of the treated substrate.

[0068] Example 3

[0069] Preparation of photoresist stripping solution: Take 10 g of the first amine compound A3, add 5 g of N,N-diisopropyl-1,3-propylenediamine and 85 g of butyl acetate, mix thoroughly and filter with a 0.1 μm filter element to obtain a photoresist stripping solution.

[0070] Photoresist stripping method: Place the photoresist stripping solution obtained in this embodiment into a stripping tank, then heat it to 60°C, place the substrate to be treated (made of copper) into the stripping solution in the stripping tank, keep the temperature constant for 10 minutes, take out the substrate, and then immerse it in isopropanol for 1 minute. After taking it out, rinse the substrate with a large amount of deionized water, and finally observe under a microscope: there is almost no photoresist residue on the surface of the treated substrate.

[0071] Example 4

[0072] Preparation of photoresist stripping solution: Take 10 g of the first amine compound A4, add 5 g of N,N-diisopropyl-1,3-propylenediamine and 85 g of butyl acetate, mix thoroughly and filter with a 0.1 μm filter element to obtain a photoresist stripping solution.

[0073] Photoresist stripping method: Place the photoresist stripping solution obtained in this embodiment into a stripping tank, then heat it to 60°C, place the substrate to be treated (made of copper) into the stripping solution in the stripping tank, keep the temperature constant for 10 minutes, take out the substrate, and then immerse it in isopropanol for 1 minute. After taking it out, rinse the substrate with a large amount of deionized water, and finally observe under a microscope: there is almost no photoresist residue on the surface of the treated substrate.

[0074] Example 5

[0075] Preparation of photoresist stripping solution: Take 5 g of the first amine compound A1, add 10 g of N-(2-hydroxyethyl)ethylenediamine and 87.5 g of butyl acetate, mix thoroughly and filter with a 0.1 μm filter element to obtain a photoresist stripping solution.

[0076] Photoresist stripping method: Place the photoresist stripping solution obtained in this embodiment into a stripping tank, then heat it to 60°C, place the substrate to be treated (made of copper) into the stripping solution in the stripping tank, keep the temperature constant for 10 minutes, take out the substrate, and then immerse it in isopropanol for 1 minute. After taking it out, rinse the substrate with a large amount of deionized water, and finally observe under a microscope: no photoresist residue on the surface of the treated substrate.

[0077] Comparative Example 1

[0078] Preparation of reference photoresist stripping solution: Take 5 g of N,N-diethyl-1,3-propylenediamine and 95 g of butyl acetate, mix them thoroughly, and filter them with a 0.1 μm filter element to obtain a reference photoresist stripping solution.

[0079] Photoresist stripping method: Place the photoresist stripping solution obtained in this comparative example into a stripping tank, then heat it to 60°C, place the substrate to be treated (made of copper) into the stripping solution in the stripping tank, keep the temperature constant for 15 minutes, take out the substrate, and then immerse it in isopropanol for 1 minute. After taking it out, rinse the substrate with a large amount of deionized water, and finally observe under a microscope: most of the photoresist pattern is removed, but a small amount of photoresist thin layer remains on the copper surface.

[0080] Comparative Example 2

[0081] Preparation of reference photoresist stripping solution: Take 10 g of N,N-diisopropyl-1,3-propylenediamine and 90 g of butyl acetate, mix them thoroughly, and filter them with a 0.1 μm filter element to obtain a reference photoresist stripping solution.

[0082] Photoresist stripping method: Place the photoresist stripping solution obtained in this comparative example into a stripping tank, then heat it to 60°C, place the substrate to be treated (made of copper) into the stripping solution in the stripping tank, keep the temperature constant for 20 minutes, take out the substrate, and then immerse it in isopropanol for 1 minute. After taking it out, rinse the substrate with a large amount of deionized water, and finally observe under a microscope: most of the photoresist pattern is removed, but a small amount of photoresist thin layer remains on the copper surface.

[0083] Comparative Example 3

[0084] Preparation of reference photoresist stripping solution: 12.5 g of the first amine compound A1 and 87.5 g of butyl acetate were taken, mixed thoroughly, and filtered through a 0.1 μm filter element to obtain a reference photoresist stripping solution.

[0085] Photoresist stripping method: the photoresist stripping solution obtained in this comparative example is placed in a stripping tank, and then heated to 70°C, and the substrate to be treated (made of copper, with a photoresist layer attached to the copper sheet) is placed in the stripping solution in the stripping tank, kept at a constant temperature for 20 minutes, and the substrate is taken out, and then immersed in isopropanol for 1 minute. After taking it out, the substrate is rinsed with a large amount of deionized water, and finally observed under a microscope: most of the photoresist pattern is removed, but a small amount of photoresist thin layer remains on the copper surface.

[0086] Test Case

[0087] For Examples 1 to 5 and Comparative Examples 1 to 3, in order to test the corrosiveness of the stripping solution to the metal substrate, samples of the stripping solution before and after the substrate was treated were taken and the Cu content in the samples was tested by inductively coupled plasma emission spectrometry. The results are shown in Table 1.

[0088] Table 1

[0089]

[0090] It can be seen from the results in Table 1 that, compared with Comparative Examples 1 to 3, after photoresist stripping using the photoresist stripping solutions provided in Examples 1 to 5, almost no photoresist residue is left on the substrate, and the Cu content in the stripping solution after treating the substrate does not change much compared with the Cu content in the stripping solution before treating the substrate, indicating that the photoresist stripping solution has low corrosiveness to the substrate. At the same time, the photoresist stripping solution is used for a shorter treatment time at the same treatment temperature and has higher efficiency.

[0091] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and intent of the present invention.

Claims

1. A photoresist stripping solution, characterized in that: The photoresist stripping solution contains a first amine compound, a second amine compound and an organic solvent I; the first amine compound has a structure as shown in formula (1) or formula (2); the second amine compound has a structure as shown in formula (3); In formula (1) and formula (2), Y is C1 to C 10 alkyl, L is a C1-C4 ester bond, X is a single bond or a C1-C 20 Alkylene, R is a hydrogen atom or C1~C 20 alkyl, R1 and R1' are each independently C1 to C 10 An alkyl group, wherein n is an integer from 1 to 3; In formula (3), R2 is a C1-C5 alkylene group, and R3 and R4 are each independently a C1-C5 alkyl group or a C1-C5 hydroxyalkyl group.

2. The photoresist stripping solution according to claim 1, characterized in that The mass ratio of the first amine compound to the second amine compound is 1:(0.5-2); preferably, based on the total mass of the photoresist stripping solution, the content of the first amine compound is 5-10wt%, the content of the second amine compound is 5-10wt%, and the content of the organic solvent is 85-90wt%.

3. The photoresist stripping solution according to claim 1, characterized in that: The first amine compound is prepared by the following method: Compound I having a structure represented by formula (4) and compound II having a structure represented by formula (5) or formula (6) are subjected to a condensation reaction in the presence of a catalyst, and the obtained product is a first amine compound having a structure represented by formula (1) or formula (2); In formula (4), Y is C1 to C 10 In formula (5) and formula (6), R6 is a hydroxyl group or a halogen group, and X is a single bond or a C1-C 20 Alkylene, R is a hydrogen atom or C1~C 20 alkyl, R1 and R1ˋ are each independently C1~C 10 wherein n is an integer of 1 to 3.

4. The photoresist stripping solution according to claim 3, characterized in that: The molar ratio of compound I to compound II is 1:(0.8-1.2); Preferably, the amount of the catalyst used is 1 to 5 wt% of the sum of the mass of compound I and compound II.

5. The photoresist stripping solution according to claim 3, characterized in that: The conditions of the condensation reaction include a temperature of 100 to 150° C. and a time of 10 to 15 hours.

6. The photoresist stripping solution according to claim 3, characterized in that: The compound I is at least one selected from p-toluic acid, p-ethylbenzoic acid, p-propylbenzoic acid, p-tolueneacetic acid, 4-isopropylphenylacetic acid, p-toluenepropionic acid, 4-ethylphenylpropionic acid, 2-(4-isopropylphenyl)propionic acid, 2-(3-isobutylphenyl)propionic acid, and 3-(4-isobutylphenyl)propionic acid; Preferably, the compound II is selected from at least one of diethylaminoethanol, dimethylaminoethanol, 3-diethylamino-1-propanol, 2-morpholinoethanol, 4-(3-hydroxypropyl)morpholine, and 1,5-oxazacyclooctanebutanol; Preferably, the catalyst is selected from at least one of dimethylaminopyridine, triethylamine, pyridine, and diisopropylethylamine; Preferably, the condensation reaction is carried out in the presence of an organic solvent II; Preferably, the organic solvent II is selected from at least one of dichloromethane, tetrahydrofuran, dimethyl sulfoxide and dimethylformamide.

7. The photoresist stripping solution according to claim 1, characterized in that: The second amine compound is selected from at least one of N,N-diethyl-1,3-propylenediamine, N,N-diisopropyl-1,3-propylenediamine and N-(2-hydroxyethyl)ethylenediamine; Preferably, the organic solvent I is selected from at least one of butyl acetate, N-ethylpyrrolidone, 4-methyl-2-pentanol, sulfolane, pyrrolidone and N-methylpyrrolidone.

8. The method for preparing a photoresist stripping solution according to any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: mixing a first amine compound, a second amine compound and an organic solvent to obtain a photoresist stripping solution.

9. A method for stripping a photoresist, characterized in that: The photoresist stripping method comprises the following steps: immersing the substrate from which the photoresist needs to be stripped in the photoresist stripping solution described in any one of claims 1 to 7, and after the immersion is completed, washing the substrate with a washing solution to complete the stripping of the photoresist on the substrate; Preferably, the soaking conditions include: the temperature of the stripping solution is 50-70° C., and the soaking time is 10-15 min.

10. Use of the photoresist stripping solution according to any one of claims 1 to 7 or the photoresist stripping method according to claim 9 in a semiconductor substrate requiring photoresist stripping.

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