Water-based photoresist stripping liquid and preparation method thereof

Abstract

The invention belongs to the technical field of stripping liquid, and particularly discloses water-based photoresist stripping liquid and a preparation method thereof. The water-based photoresist stripping liquid is prepared from the following raw materials in percentage by mass: 10 to 15 percent of quaternary ammonium salt compound, 15 to 25 percent of water-soluble organic solvent, 0.2 to 0.5 percent of alkanolamine substance, 0.03 to 0.05 percent of metal protective agent and the balance of deionized water, the quaternary ammonium salt compound is prepared by the following steps: reacting 6-heptene-1-alcohol with ethylene oxide to obtain a compound 1, carrying out amidation reaction on allyl glycidyl ether and dimethylamine to obtain a compound 2, and carrying out chlorination reaction on sodium 2-chloroethanesulfonate and the compound 2 to obtain a compound 3; and finally polymerizing the compound 1 and the compound 3 under the initiation action of azodiisobutyronitrile. All the components in the stripping liquid have a synergistic effect, so that the photoresist is effectively stripped, and the stripping liquid is free of residues, more efficient and good in corrosion-resistant effect.

Description

Technical Field

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

[0002] In the manufacturing process of liquid crystal display panels, the photolithography process is a core step in pattern transfer, and its quality directly determines key panel performance, such as resolution and contrast. Photoresist removal, a crucial post-processing step in the photolithography process, removes residual photoresist after exposure and development, providing a clean surface for subsequent thin-film deposition, etching, and other processes. Common photoresist stripping solutions are divided into two main types: organic and aqueous. Organic strippers, with their strong swelling capacity and high dissolution rates, offer significant advantages in removing complex photoresist structures. Aqueous strippers, with their environmentally friendly and low-toxic properties, are a key development direction in green manufacturing. However, organic strippers are prone to leaving residual photoresist residue after swelling due to excessive surface tension. If this residual photoresist enters subsequent film deposition or etching processes, it can cause serious defects such as short circuits and open circuits. While aqueous strippers can effectively reduce the risk of residual residue, their limited dissolution efficiency makes them inadequate for high production capacity requirements. Furthermore, strippers often contain high levels of amines, which can corrode metal wiring and affect the performance and reliability of display panels.

[0003] At present, invention patent CN119270600A discloses an aqueous photoresist stripping solution for display panels, its preparation method and application. The aqueous photoresist stripping solution for display panels comprises the following components, calculated by weight: 0.1-0.5 parts of a composite functional agent; 15-25 parts of an organic amine; 10-20 parts of a polar solvent; 1-5 parts of a metal resist; 30-50 parts of ultrapure water; the composite functional agent is a mixture of graphene oxide and an electron-rich water-soluble compound; the electron-rich water-soluble compound is one or more of polyacrylamide, polyacrylic acid, polyvinyl pyrrolidone, polyvinyl alcohol, polymaleic anhydride, polyquaternary ammonium salt, polyethylene glycol, and polyethyleneimine; the organic amine is ethanolamine, N-methylethanolamine, diethanolamine, triethanolamine, isopropanolamine, 2-aminoethanolamine, ethyldiethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, N- The polar solvent is one or more of (2-aminoethyl)ethanolamine and diglycolamine; the polar solvent is one or more of N-methylformamide, N-methylpyrrolidone, dimethyl sulfoxide, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether; the metal resist is one or more of glycerol, diethylene glycol, catechol, 4-methylcatechol, 4-tert-butylcatechol, 1,2,4-triazole, 3-amino-1,2,4-triazole, 4-amino-1,2,4-triazole, benzotriazole, mercaptobenzothiazole, imidazole, and phosphine carboxylic acid; the photoresist stripping solution mainly solves the problem that the volatilization of organic solvents and ultrapure water in water-based photoresist stripping solutions is relatively serious, the operation risk in the process is relatively large, and the service life of the water-based stripping solution is affected. However, the problem of how to remove the photoresist while reducing the corrosion of the metal film layer has not yet been properly solved.

[0004] Based on the above statements, the present invention provides an aqueous photoresist stripping solution and a preparation method thereof. Summary of the Invention

[0005] The invention provides an aqueous photoresist stripping solution and a preparation method thereof. By preparing a novel quaternary ammonium salt compound, the aqueous photoresist stripping solution can effectively remove residual photoresist without causing corrosion to the metal film layer.

[0006] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions: In a first aspect, the present invention provides an aqueous photoresist stripping solution, comprising the following raw materials in percentage by mass: 10-15% of a quaternary ammonium salt compound, 15-25% of a water-soluble organic solvent, 0.2-0.5% of an alkanolamine substance, 0.03-0.05% of a metal protective agent, and the balance being deionized water; The quaternary ammonium salt compound has a structure shown in formula (1): (1) In formula (1), x is any integer within the range of 10-18; y is any integer within the range of 5-11; and n is any integer within the range of 20-25.

[0007] Preferably, the quaternary ammonium salt compound is prepared by the following steps: Step (1), 6-heptene-1-ol and potassium hydroxide are mixed evenly, vacuumized, and ethylene oxide is introduced. After the introduction is completed, the temperature is raised to 120-135°C, and the reaction is kept at this temperature for 2-5 hours, and then cooled. Unreacted ethylene oxide in the reaction mass is removed under reduced pressure, and the pressure is released to obtain compound 1; Step (2), adding dimethylamine methanol solution to allyl glycidyl ether, mixing evenly, heating to 75-85°C, reflux reaction for 5-8h, distilling under reduced pressure, washing, and drying to obtain compound 2; Step (3), adding compound 2 and sodium 2-chloroethylsulfonate to anhydrous ethanol, heating to 50-60°C, reacting for 5-8 hours, distilling under reduced pressure, washing, and drying to obtain compound 3; Step (4): Compound 1, Compound 3 and azobisisobutyronitrile are added to anhydrous ethanol, reacted at 65-75° C. for 0.5-1.5 h, and then distilled under reduced pressure, washed, and dried to obtain a quaternary ammonium salt compound.

[0008] In the preparation process of quaternary ammonium salt compounds, the chemical reaction equations involved are as follows: .

[0009] Preferably, the molar ratio of 6-heptene-1-ol, potassium hydroxide and ethylene oxide in step (1) is 1 mol: (0.1-0.5) mol: (20-25) mol.

[0010] Preferably, in step (2), the ratio of allyl glycidyl ether to dimethylamine methanol solution is 1 mol: (120-180) mL, and the concentration of the dimethylamine methanol solution is 30-40 wt%.

[0011] Preferably, the ratio of the compound 2, sodium 2-chloroethylsulfonate and anhydrous ethanol used in step (3) is 1 mol: (1.1-2) mol: (200-400) mL.

[0012] Preferably, the ratio of compound 1, compound 3, azobisisobutyronitrile and anhydrous ethanol in step (4) is 1 mol: (0.5-1) mol: (0.01-0.1) mol: (400-800) mL.

[0013] Preferably, the water-soluble organic solvent is at least one of N-methylpyrrolidone, acetonitrile, diethylene glycol methyl ether, diethylene glycol ethyl ether, propylene glycol methyl ether, and isopropyl alcohol.

[0014] Preferably, the alkanolamine substance is at least one of monoethanolamine, diethanolamine, triethanolamine and monopropanolamine.

[0015] Preferably, the metal protective agent is at least one of benzotriazole, toluenetriazole, benzothiazole, and methimazole.

[0016] In a second aspect, the present invention provides a method for preparing an aqueous photoresist stripping solution, comprising the following steps: adding a quaternary ammonium salt compound, a water-soluble organic solvent, an alkanolamine substance and a metal protective agent to deionized water, stirring evenly, and obtaining an aqueous photoresist stripping solution. Beneficial effects

[0017] The quaternary ammonium salt compound of the present invention is obtained by reacting 6-heptene-1-ol with ethylene oxide to obtain compound 1, utilizing the amidation reaction of allyl glycidyl ether and dimethylamine to obtain compound 2, utilizing the chlorination reaction of 2-chloroethyl sulfonate and compound 2 to obtain compound 3, and finally allowing compound 1 and compound 3 to be polymerized under the initiation of azobisisobutyronitrile to obtain the quaternary ammonium salt compound; when it is added to a stripping solution system, the surface tension of the system can be significantly reduced, so that the stripping solution is more easily penetrated between the photoresist to be stripped and the substrate; and due to the presence of ether bonds and sulfonate radicals in the quaternary ammonium salt compound, the wetting, dissolution and adsorption of the active ingredient in the stripping solution on the photoresist are promoted; simultaneously, the quaternary ammonium salt compound can improve the dispersion stability of the stripping solution, and then better make up for the defect of the sol performance decline caused by the reduction in the addition of the organic solvent, and then achieve effective stripping of the photoresist, without residue, and more efficiently. In addition, the stripping solution of the present invention avoids the addition of traditional organic amines, and under the synergistic effect of the quaternary ammonium salt compound and the metal protective agent, achieves an excellent corrosion resistance effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0019] Figure 1 OM image of the sample after stripping using the stripping solution of Example 1; Figure 2 OM image of the sample after stripping using the stripping solution of Comparative Example 1; Figure 3 OM image of the sample after stripping using the stripping solution of Comparative Example 2; Figure 4OM image of the sample after stripping using the stripping solution of Comparative Example 3; Figure 5 OM image of the sample after stripping using the stripping solution of Comparative Example 4; Figure 6 This is the SEM image of the original sample before stripping with stripping liquid; Figure 7 This is a SEM image of the sample after being stripped using the stripping solution of Example 1; Figure 8 This is an SEM image of the sample after stripping using the stripping solution of Comparative Example 1; Figure 9 This is an SEM image of the sample after stripping using the stripping solution of Comparative Example 2; Figure 10 This is an SEM image of the sample after stripping using the stripping solution of Comparative Example 3; Figure 11 This is an SEM image of the sample after stripping using the stripping solution of Comparative Example 4. DETAILED DESCRIPTION

[0020] In order to more clearly illustrate the overall concept of the present invention, the overall scheme of the present invention is described in detail below in the form of embodiments; in the following description, a large number of specific details are given to provide a more thorough understanding of the present invention; however, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details; in other examples, in order to avoid confusion with the present invention, some technical features known in the art are not described.

[0021] Unless otherwise specified, all raw material components in the following examples can be purchased from commercial sources, the experimental instruments used are conventional laboratory instruments, and the performance testing methods are known in the art.

[0022] Preparation Example 1 Quaternary ammonium salt compound-1 is prepared by the following steps: Step (1), 0.5 mol of 6-heptene-1-ol and 0.25 mol of potassium hydroxide were mixed evenly, vacuumed, and 11 mol of ethylene oxide was introduced. After the introduction was completed, the temperature was raised to 135° C., kept warm for 2 hours, and then cooled. Unreacted ethylene oxide in the reaction mass was removed under reduced pressure, and the pressure was released to obtain compound 1; Step (2), adding 90 mL of a 30 wt% dimethylamine methanol solution to 0.5 mol of allyl glycidyl ether, mixing evenly, heating to 75°C, reflux for 5 hours, distilling under reduced pressure, washing, and drying to obtain compound 2; Step (3), add 0.5 mol of compound 2 obtained in step (2) and 0.78 mol of sodium 2-chloroethylsulfonate to 150 mL of anhydrous ethanol, heat to 50°C, react for 5 hours, distill under reduced pressure, wash, and dry to obtain compound 3; Step (4): 0.5 mol of compound 1 obtained in step (1), 0.325 mol of compound 3 obtained in step (3) and 0.01 mol of azobisisobutyronitrile were added to 300 mL of anhydrous ethanol, reacted at 75° C. for 1 h, and then distilled under reduced pressure, washed, and dried to obtain quaternary ammonium salt compound-1.

[0023] Preparation Example 2 Preparation Example 2 is the same as Preparation Example 1, except that the amount of ethylene oxide added is 5 mol, as follows: Quaternary ammonium salt compound-2 is prepared by the following steps: Step (1), 0.5 mol of 6-heptene-1-ol and 0.25 mol of potassium hydroxide were mixed evenly, vacuumed, and 5 mol of ethylene oxide was introduced. After the introduction was completed, the temperature was raised to 135° C., kept warm for 2 hours, and then cooled. Unreacted ethylene oxide in the reaction mass was removed under reduced pressure, and the pressure was released to obtain compound 1; Step (2), adding 90 mL of a 30 wt% dimethylamine methanol solution to 0.5 mol of allyl glycidyl ether, mixing evenly, heating to 75°C, reflux for 5 hours, distilling under reduced pressure, washing, and drying to obtain compound 2; Step (3), add 0.5 mol of compound 2 obtained in step (2) and 0.78 mol of sodium 2-chloroethylsulfonate to 150 mL of anhydrous ethanol, heat to 50°C, react for 5 hours, distill under reduced pressure, wash, and dry to obtain compound 3; Step (4): 0.5 mol of compound 1 obtained in step (1), 0.325 mol of compound 3 obtained in step (3) and 0.01 mol of azobisisobutyronitrile were added to 300 mL of anhydrous ethanol, reacted at 75° C. for 1 h, and then distilled under reduced pressure, washed, and dried to obtain quaternary ammonium salt compound-2.

[0024] Preparation Example 3 Preparation Example 3 is the same as Preparation Example 1, except that the amount of compound 3 added is 0.1 mol, as follows: Quaternary ammonium salt compound-3 is prepared by the following steps: Step (1), 0.5 mol of 6-heptene-1-ol and 0.25 mol of potassium hydroxide were mixed evenly, vacuumed, and 11 mol of ethylene oxide was introduced. After the introduction was completed, the temperature was raised to 135° C., kept warm for 2 hours, and then cooled. Unreacted ethylene oxide in the reaction mass was removed under reduced pressure, and the pressure was released to obtain compound 1; Step (2), adding 90 mL of a 30 wt% dimethylamine methanol solution to 0.5 mol of allyl glycidyl ether, mixing evenly, heating to 75°C, reflux for 5 hours, distilling under reduced pressure, washing, and drying to obtain compound 2; Step (3), add 0.5 mol of compound 2 obtained in step (2) and 0.78 mol of sodium 2-chloroethylsulfonate to 150 mL of anhydrous ethanol, heat to 50°C, react for 5 hours, distill under reduced pressure, wash, and dry to obtain compound 3; Step (4): 0.5 mol of compound 1 obtained in step (1), 0.1 mol of compound 3 obtained in step (3) and 0.01 mol of azobisisobutyronitrile were added to 300 mL of anhydrous ethanol, reacted at 75° C. for 1 h, and then distilled under reduced pressure, washed, and dried to obtain quaternary ammonium salt compound-3.

[0025] Preparation Example 4 Preparation Example 4 is the same as Preparation Example 1, except that the amount of compound 3 added is 0.7 mol, as follows: Quaternary ammonium salt compound-4 is prepared by the following steps: Step (1), 0.5 mol of 6-heptene-1-ol and 0.25 mol of potassium hydroxide were mixed evenly, vacuumed, and 11 mol of ethylene oxide was introduced. After the introduction was completed, the temperature was raised to 135° C., kept warm for 2 hours, and then cooled. Unreacted ethylene oxide in the reaction mass was removed under reduced pressure, and the pressure was released to obtain compound 1; Step (2), adding 90 mL of a 30 wt% dimethylamine methanol solution to 0.5 mol of allyl glycidyl ether, mixing evenly, heating to 75°C, reflux for 5 hours, distilling under reduced pressure, washing, and drying to obtain compound 2; Step (3), add 0.5 mol of compound 2 obtained in step (2) and 0.78 mol of sodium 2-chloroethylsulfonate to 150 mL of anhydrous ethanol, heat to 50°C, react for 5 hours, distill under reduced pressure, wash, and dry to obtain compound 3; Step (4): 0.5 mol of compound 1 obtained in step (1), 0.7 mol of compound 3 obtained in step (3) and 0.01 mol of azobisisobutyronitrile were added to 300 mL of anhydrous ethanol, reacted at 75° C. for 1 h, and then distilled under reduced pressure, washed, and dried to obtain quaternary ammonium salt compound-4.

[0026] Example 1 A water-based photoresist stripping solution is composed of the following raw materials in percentage by mass: 10% of a quaternary ammonium salt compound, 15% of a water-soluble organic solvent, 0.2% of an alkanolamine substance, 0.03% of a metal protective agent, and the balance being deionized water; The quaternary ammonium salt compound is quaternary ammonium salt compound-1; the water-soluble organic solvent is obtained by mixing acetonitrile and diethylene glycol methyl ether in a volume ratio of 10:3; the alkanolamine substance is monoethanolamine; and the metal protective agent is benzotriazole; A method for preparing an aqueous photoresist stripping solution comprises the following steps: A quaternary ammonium salt compound, a water-soluble organic solvent, an alkanolamine substance and a metal protective agent are added into deionized water and stirred evenly to obtain an aqueous photoresist stripping solution.

[0027] Example 2 A water-based photoresist stripping solution is composed of the following raw materials in percentage by mass: 13% of a quaternary ammonium salt compound, 20% of a water-soluble organic solvent, 0.4% of an alkanolamine substance, 0.04% of a metal protective agent, and the balance being deionized water; The quaternary ammonium salt compound is quaternary ammonium salt compound-1; the water-soluble organic solvent is obtained by mixing acetonitrile and N-methylpyrrolidone in a volume ratio of 1:1; the alkanolamine substance is monopropanolamine; and the metal protective agent is toluenetriazole; A method for preparing an aqueous photoresist stripping solution comprises the following steps: A quaternary ammonium salt compound, a water-soluble organic solvent, an alkanolamine substance and a metal protective agent are added into deionized water and stirred evenly to obtain an aqueous photoresist stripping solution.

[0028] Example 3 A water-based photoresist stripping solution is composed of the following raw materials in percentage by mass: 15% of a quaternary ammonium salt compound, 25% of a water-soluble organic solvent, 0.5% of an alkanolamine substance, 0.05% of a metal protective agent, and the balance being deionized water; The quaternary ammonium salt compound is quaternary ammonium salt compound-1; the water-soluble organic solvent is obtained by mixing isopropyl alcohol and diethylene glycol methyl ether in a volume ratio of 4:3; the alkanolamine substance is triethanolamine; and the metal protective agent is methimazole; A method for preparing an aqueous photoresist stripping solution comprises the following steps: A quaternary ammonium salt compound, a water-soluble organic solvent, an alkanolamine substance and a metal protective agent are added into deionized water and stirred evenly to obtain an aqueous photoresist stripping solution.

[0029] Comparative Example 1 Comparative Example 1, the specific steps are the same as in Example 1, except that the quaternary ammonium compound is quaternary ammonium compound-2, specifically as follows: A water-based photoresist stripping solution is composed of the following raw materials in percentage by mass: 10% of a quaternary ammonium salt compound, 15% of a water-soluble organic solvent, 0.2% of an alkanolamine substance, 0.03% of a metal protective agent, and the balance being deionized water; The quaternary ammonium salt compound is quaternary ammonium salt compound-2; the water-soluble organic solvent is obtained by mixing acetonitrile and diethylene glycol methyl ether in a volume ratio of 10:3; the alkanolamine substance is monoethanolamine; and the metal protective agent is benzotriazole; A method for preparing an aqueous photoresist stripping solution comprises the following steps: A quaternary ammonium salt compound, a water-soluble organic solvent, an alkanolamine substance and a metal protective agent are added into deionized water and stirred evenly to obtain an aqueous photoresist stripping solution.

[0030] Comparative Example 2 Comparative Example 2, the specific steps are the same as in Example 1, except that the quaternary ammonium compound is quaternary ammonium compound-3, specifically as follows: A water-based photoresist stripping solution is composed of the following raw materials in percentage by mass: 10% of a quaternary ammonium salt compound, 15% of a water-soluble organic solvent, 0.2% of an alkanolamine substance, 0.03% of a metal protective agent, and the balance being deionized water; The quaternary ammonium salt compound is quaternary ammonium salt compound-3; the water-soluble organic solvent is obtained by mixing acetonitrile and diethylene glycol methyl ether in a volume ratio of 10:3; the alkanolamine substance is monoethanolamine; and the metal protective agent is benzotriazole; A method for preparing an aqueous photoresist stripping solution comprises the following steps: A quaternary ammonium salt compound, a water-soluble organic solvent, an alkanolamine substance and a metal protective agent are added into deionized water and stirred evenly to obtain an aqueous photoresist stripping solution.

[0031] Comparative Example 3 Comparative Example 3, the specific steps are the same as in Example 1, except that the quaternary ammonium compound is quaternary ammonium compound-4, specifically as follows: A water-based photoresist stripping solution is composed of the following raw materials in percentage by mass: 10% of a quaternary ammonium salt compound, 15% of a water-soluble organic solvent, 0.2% of an alkanolamine substance, 0.03% of a metal protective agent, and the balance being deionized water; The quaternary ammonium salt compound is quaternary ammonium salt compound-4; the water-soluble organic solvent is obtained by mixing acetonitrile and diethylene glycol methyl ether in a volume ratio of 10:3; the alkanolamine substance is monoethanolamine; and the metal protective agent is benzotriazole; A method for preparing an aqueous photoresist stripping solution comprises the following steps: A quaternary ammonium salt compound, a water-soluble organic solvent, an alkanolamine substance and a metal protective agent are added into deionized water and stirred evenly to obtain an aqueous photoresist stripping solution.

[0032] Comparative Example 4 Comparative Example 4, the specific steps are the same as in Example 1, except that the quaternary ammonium salt compound is hexadecyltrimethylammonium hydroxide, specifically as follows: A water-based photoresist stripping solution is composed of the following raw materials in percentage by mass: 10% of a quaternary ammonium salt compound, 15% of a water-soluble organic solvent, 0.2% of an alkanolamine substance, 0.03% of a metal protective agent, and the balance being deionized water; The quaternary ammonium salt compound is hexadecyltrimethylammonium hydroxide; the water-soluble organic solvent is obtained by mixing acetonitrile and diethylene glycol methyl ether in a volume ratio of 10:3; the alkanolamine substance is monoethanolamine; and the metal protective agent is benzotriazole; A method for preparing an aqueous photoresist stripping solution comprises the following steps: A quaternary ammonium salt compound, a water-soluble organic solvent, an alkanolamine substance and a metal protective agent are added into deionized water and stirred evenly to obtain an aqueous photoresist stripping solution.

[0033] Performance Testing Stripping method: At 60°C, the copper substrate sample containing the photoresist was immersed in the photoresist stripping solution prepared in the embodiments of the present invention and the comparative example for stripping for 120 seconds, then rinsed with ultrapure water for 1 minute, and finally dried with high-purity nitrogen to prepare a sample after stripping with the photoresist stripping solution.

[0034] Stripping effect: After stripping the photoresist stripping liquid, the sample was cleaned. After cleaning, the plane was observed using OM and the cross-section was observed using SEM. OM was used to check whether there was any photoresist residue, and SEM was used to check the corrosion of the metal material. Stripping evaluation: A: no residue; B: a small amount of residue; C: a large amount of residue; Corrosion evaluation: A: the metal layer was not corroded, B: the metal layer was slightly corroded, C: the metal layer was corroded; Film thickness change = metal film thickness of the original sample - metal film thickness of the sample after stripping. The specific results are shown in Table 1.

[0035] Table 1

[0036] As can be seen from the above table, the performance of the stripping solutions of Examples 1-3 is significantly better than that of Comparative Examples 1-4.

[0037] The OM image of the sample was collected during the stripping process. The results are as follows: Figure 1-5 As shown, Figure 1 OM image of the sample after stripping using the stripping solution of Example 1; Figure 2 OM image of the sample after stripping using the stripping solution of Comparative Example 1; Figure 3 OM image of the sample after stripping using the stripping solution of Comparative Example 2; Figure 4 OM image of the sample after stripping using the stripping solution of Comparative Example 3; Figure 5 This is the OM image of the sample after stripping using the stripping solution of Comparative Example 4.

[0038] The SEM images of the samples during the stripping process were collected. The results are as follows: Figure 6-11 As shown, Figure 6 This is the SEM image of the original sample before stripping with stripping liquid; Figure 7 This is a SEM image of the sample after being stripped using the stripping solution of Example 1; Figure 8 This is an SEM image of the sample after stripping using the stripping solution of Comparative Example 1; Figure 9 This is an SEM image of the sample after stripping using the stripping solution of Comparative Example 2; Figure 10 This is an SEM image of the sample after stripping using the stripping solution of Comparative Example 3; Figure 11 This is an SEM image of the sample after stripping using the stripping solution of Comparative Example 4.

[0039] comprehensive Figure 1-11 From the data in Table 1, it can be seen from the comparison between Example 1 and Comparative Example 1 that Comparative Example 1 uses quaternary ammonium salt compound-2. During its preparation process, too little ethylene oxide is added, which makes it difficult for quaternary ammonium salt compound-2 to fully infiltrate the photoresist surface, hindering the stripping solution from penetrating into the interior of the photoresist, resulting in an increase in stripping residues and a reduction in the stripping effect.

[0040] By comparing Example 1 with Comparative Example 2 and Comparative Example 3, it can be seen that Comparative Example 2 adopts quaternary ammonium salt compound-3 and Comparative Example 3 adopts quaternary ammonium salt compound-4. During their preparation process, the addition amount of compound 3 is not within a reasonable range, which will result in insufficient wettability of the quaternary ammonium salt compound to the photoresist, and also cause corrosion of the metal film layer to a certain extent, resulting in poor stripping effect.

[0041] Comparison of Example 1 and Comparative Example 4 shows that when hexadecyltrimethylammonium hydroxide is used in equal amounts to replace the quaternary ammonium salt compound-1, the solubility of the stripping solution system for the photoresist is affected, and the overall performance of the stripping solution is significantly reduced.

[0042] It should be noted that the above disclosed embodiments only reflect the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention is described in detail with reference to the preferred embodiments, anyone familiar with the technical field should understand that modifications or various changes, equivalent substitutions, without departing from the scope of the technical solution of the present invention, should all fall within the scope of protection of the present invention.

Claims

1. A water-based photoresist stripping solution, characterized in that: The invention is composed of the following raw materials in percentage by mass: 10-15% of a quaternary ammonium salt compound, 15-25% of a water-soluble organic solvent, 0.2-0.5% of an alkanolamine substance, 0.03-0.05% of a metal protective agent, and the balance being deionized water; The quaternary ammonium salt compound has a structure shown in formula (1): （1） In formula (1), x is any integer within the range of 10-18; y is any integer within the range of 5-11; and n is any integer within the range of 20-25.

2. The aqueous photoresist stripping solution according to claim 1, wherein The quaternary ammonium salt compound is prepared by the following steps: Step (1), 6-heptene-1-ol and potassium hydroxide are mixed evenly, vacuumized, and ethylene oxide is introduced. After the introduction is completed, the temperature is raised to 120-135°C, and the reaction is kept at this temperature for 2-5 hours, and then cooled. Unreacted ethylene oxide in the reaction mass is removed under reduced pressure, and the pressure is released to obtain compound 1; Step (2), adding dimethylamine methanol solution to allyl glycidyl ether, mixing evenly, heating to 75-85°C, reflux reaction for 5-8h, distilling under reduced pressure, washing, and drying to obtain compound 2; Step (3), adding compound 2 and sodium 2-chloroethylsulfonate to anhydrous ethanol, heating to 50-60°C, reacting for 5-8 hours, distilling under reduced pressure, washing, and drying to obtain compound 3; Step (4): Compound 1, Compound 3 and azobisisobutyronitrile are added to anhydrous ethanol, reacted at 65-75° C. for 0.5-1.5 h, and then distilled under reduced pressure, washed, and dried to obtain a quaternary ammonium salt compound.

3. The aqueous photoresist stripping solution according to claim 2, wherein: The molar ratio of 6-heptene-1-ol, potassium hydroxide and ethylene oxide in step (1) is 1 mol: (0.1-0.5) mol: (20-25) mol.

4. The aqueous photoresist stripping solution according to claim 2, wherein: In step (2), the ratio of allyl glycidyl ether to dimethylamine methanol solution is 1 mol: (120-180) mL, and the concentration of the dimethylamine methanol solution is 30-40 wt%.

5. The aqueous photoresist stripping solution according to claim 2, characterized in that: In step (3), the ratio of compound 2, sodium 2-chloroethylsulfonate and anhydrous ethanol is 1 mol: (1.1-2) mol: (200-400) mL.

6. The aqueous photoresist stripping solution according to claim 2, characterized in that: The ratio of compound 1, compound 3, azobisisobutyronitrile and anhydrous ethanol used in step (4) is 1 mol: (0.5-1) mol: (0.01-0.1) mol: (400-800) mL.

7. The aqueous photoresist stripping solution according to claim 1, characterized in that: The water-soluble organic solvent is at least one of N-methylpyrrolidone, acetonitrile, diethylene glycol methyl ether, diethylene glycol ethyl ether, propylene glycol methyl ether, and isopropyl alcohol.

8. The aqueous photoresist stripping solution according to claim 1, characterized in that: The alkanolamine substance is at least one of monoethanolamine, diethanolamine, triethanolamine and monopropanolamine.

9. The aqueous photoresist stripping solution according to claim 1, characterized in that: The metal protective agent is at least one of benzotriazole, toluenetriazole, benzothiazole and methimazole.

10. A method for preparing the aqueous photoresist stripping solution according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: adding a quaternary ammonium salt compound, a water-soluble organic solvent, an alkanolamine substance and a metal protective agent into deionized water, and stirring the mixture evenly to obtain a water-based photoresist stripping solution.

Images