Cleaning solution for mask plate and preparation method of cleaning solution

Abstract

The invention discloses a cleaning solution for a mask plate and a preparation method of the cleaning solution, and belongs to the field of photoetching technology cleaning, and the preparation method comprises the following steps: weighing all components according to a formula, adding 5-30 parts by weight of inorganic alkali salt into 50-300 parts by weight of water, stirring for 5-8 minutes, then adding 1-10 parts by weight of an auxiliary agent, and continuously stirring for 3-5 minutes to obtain the cleaning solution for the mask plate. Then adding 0.5-4 parts by weight of a bis-PGA-PPG grafted phosphate surfactant, 0.5-6 parts by weight of dicetyl phosphate and 0.2-3 parts by weight of isooctyl alcohol polyoxyethylene ether phosphate, and homogenizing for 1-3 minutes to obtain the cleaning solution for the mask plate. Wherein the auxiliary agent is diethylene glycol ethyl ether and / or propylene glycol methyl ether acetate; the double PGA-PPG grafted phosphate ester surfactant is obtained by reacting a double phosphate ester intermediate with a PGA-PPG polymer. The cleaning solution for the mask plate has a good cleaning effect, various pollutants on the surface of the mask plate can be effectively removed, the mask plate cannot be damaged, and the service life of the mask plate is prolonged.

Description

Technical Field

[0001] The invention belongs to the field of photolithography cleaning, and in particular relates to a cleaning liquid for a mask and a preparation method thereof. Background Art

[0002] The mask is an indispensable key component in semiconductor manufacturing, microelectronics processing and printed circuit board production. It is made of high-precision quartz glass or soda glass, covered with a thin layer of opaque light-shielding film on the surface. The designed circuit pattern is etched on the surface through precise photolithography technology to form a pattern template. When the photolithography process is carried out, the mask is placed on top of the silicon wafer or substrate coated with photoresist. It is irradiated by a light source of a specific wavelength. Only the light that passes through the transparent part of the mask can reach the photoresist layer below, and then the pattern is transferred to the photoresist with extremely high resolution. This process is crucial to ensure the performance and quality of products such as integrated circuits or display panels. However, in the actual production process, due to the influence of various external factors, dust particles, chemical residues or other contaminants will inevitably accumulate on the surface of the mask, which will not only affect the clarity of the pattern, but also may cause defects during exposure, thereby affecting the yield rate. Therefore, it is particularly important to thoroughly clean the mask regularly. Effective cleaning can not only remove surface dust and residues, restore the transparency and flatness of the mask, ensure the accuracy of pattern transfer, but also extend the service life of the mask, reduce frequent replacement due to quality problems, and thus save production costs. In addition, with the advancement of science and technology, especially the semiconductor industry's development towards smaller line widths and higher integration, the requirements for mask cleanliness are also increasing, and any slight contamination may become a key factor affecting product quality.

[0003] Chinese patent CN107870510A discloses a photomask cleaning method and a degumming method, comprising the following steps: first, using a mixture of sulfuric acid and hydrogen peroxide as a cleaning solution to clean the mask, then using a mixture of ammonia, hydrogen peroxide and deionized water as a cleaning solution to clean the mask, and then cleaning the mask with ultrasonic waves and hot deionized water; the cleaning method of this patent can remove the residual photoresist on the surface of the mask and improve the cleanliness of the mask surface; Chinese patent CN106200259A discloses a photomask cleaning process with a low sulfate residue concentration, comprising the following steps: first, using an SPM solution to perform a total cleaning on the surface of the photomask, the SPM solution being a cleaning solution formed by a mixture of sulfuric acid and hydrogen peroxide. The photomask is then sprayed with cold water and hot water in turn, and then sprayed with SC1 solution plus megasonics to clean the photomask, wherein the SC1 solution is a cleaning solution formed by a mixture of ammonia and hydrogen peroxide, and then heated for diffusion and treated with ultraviolet light, and finally washed with hot water twice, washed with SC1 solution plus megasonics twice, and washed with cold water twice, and then dried; the cleaning method of the patent can reduce the residual concentration of sulfate ions, thereby increasing the service life of the mask; however, the cleaning method of the above patent cannot efficiently and thoroughly remove pollutants on the surface of the mask, and residual sulfate ions, ammonium ions, etc. may cause wafer defects, or the cleaning process may be cumbersome and inefficient; therefore, the cleaning solution for the mask still needs to be optimized and improved. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a mask cleaning liquid, which further improves the cleaning effect of the mask cleaning liquid by using a specific dual PGA-PPG grafted phosphate surfactant in combination with other components, and can effectively remove various pollutants on the mask surface without causing damage to the mask itself. The present invention also provides a preparation method of the mask cleaning liquid.

[0005] A cleaning liquid for a mask plate, comprising the following components: Inorganic alkali salt, bis-PGA-PPG grafted phosphate surfactant, dicetyl phosphate, isooctyl alcohol polyoxyethylene ether phosphate, additives, water.

[0006] Preferably, a cleaning solution for a mask plate comprises the following components in parts by weight: 5-30 parts by weight of inorganic alkali salt, 0.5-4 parts by weight of bis-PGA-PPG grafted phosphate surfactant, 0.5-6 parts by weight of dicetyl phosphate, 0.2-3 parts by weight of isooctyl alcohol polyoxyethylene ether phosphate, 1-10 parts by weight of auxiliary agent, and 50-300 parts by weight of water.

[0007] Preferably, a cleaning solution for a mask plate comprises the following components in parts by weight: 10-15 parts by weight of inorganic alkali salt, 1-2 parts by weight of bis-PGA-PPG grafted phosphate surfactant, 1-3 parts by weight of dicetyl phosphate, 0.5-1.5 parts by weight of isooctyl alcohol polyoxyethylene ether phosphate, 3-5 parts by weight of auxiliary agent, and 100-150 parts by weight of water.

[0008] Preferably, the inorganic alkali salt is one or a mixture of two or more of sodium carbonate, potassium carbonate, sodium phosphate, potassium phosphate, and sodium silicate.

[0009] Preferably, the auxiliary agent is diethylene glycol ethyl ether and / or propylene glycol methyl ether acetate.

[0010] Preferably, the auxiliary agent is a mixture of diethylene glycol ethyl ether and propylene glycol methyl ether acetate in a weight ratio of 5:1-3.

[0011] The cleaning liquid for mask of the present invention achieves efficient, mild and environmentally friendly cleaning effect through a carefully designed component formula. The cleaning liquid is mainly composed of the above-mentioned inorganic alkali salt, a self-made double PGA-PPG grafted phosphate surfactant, dicetyl phosphate, isooctyl alcohol polyoxyethylene ether phosphate, an auxiliary agent composed of diethylene glycol ethyl ether and propylene glycol methyl ether acetate, and water. The synergistic effect between the components can not only effectively remove various pollutants on the surface of the mask, but also ensure that the mask itself is not damaged, thereby extending its service life.

[0012] First, inorganic alkali salts (such as sodium carbonate) dissociate in water and partially hydrolyze to form alkali (sodium hydroxide), making the cleaning solution moderately alkaline. This alkaline condition helps to destroy the molecular bonds of organic residues such as photoresist and acrylic glue, causing them to disintegrate and fall off the surface of the mask. In addition, inorganic alkali salts (such as sodium carbonate) also have a certain buffering capacity, which can maintain a stable pH value during the cleaning process and prevent excessive alkalinity from corroding the mask. Compared with strong alkali, sodium carbonate has moderate alkalinity, which can effectively remove pollutants without damaging the glass substrate or coating.

[0013] Secondly, the self-made double PGA-PPG grafted phosphate surfactant of the present invention is one of the core innovations of the cleaning solution formula. This surfactant is endowed with excellent performance by grafting polyglycolic acid (PGA) / polypropylene glycol (PPG) and introducing phosphate groups. PGA has good biocompatibility and water solubility, while PPG has excellent wetting and penetration capabilities; the presence of phosphate groups significantly improves the emulsification and dispersion properties of the surfactant, and can also precipitate hydrogen under electrolytic conditions to accelerate the decomposition of organic residues; in addition, phosphate groups can also form complexes with metal surfaces to inhibit corrosion and protect the mask from chemical corrosion; the double phosphate ion end brings the two PGA-PPG hydrophobic chains closer together, and can form a strong hydrophobic binding force, so that the pollutant particles after elution are stably present in the cleaning solution, preventing dust particles and other pollutant particles from re-depositing on the mask surface, and the double PGA-PPG hydrophobic chains enhance the emulsification performance and strengthen the emulsification cleaning ability of oil and fat pollutants, thereby achieving the purpose of effectively removing stubborn pollutants while maintaining the integrity and functionality of the mask.

[0014] Secondly, dicetyl phosphate can emulsify oily pollutants into tiny particles, which are easy to be carried away by water. It also has good lubrication properties, which can reduce friction during the cleaning process and prevent scratches on the mask surface. Isooctyl alcohol polyoxyethylene ether phosphate not only enhances the emulsification and dispersion capabilities of the cleaning fluid, but is also particularly beneficial for handling complex organic pollutants. At the same time, as an alkali-resistant penetrant, it still maintains good penetration properties in an alkaline environment, quickly penetrates into the photoresist or other organic residues, and accelerates their decomposition and removal.

[0015] Finally, the additive diethylene glycol ethyl ether is often used in the formulation of industrial cleaning agents and is also a mutual solvent in paints and inks. It can provide good solubility and fluidity in the cleaning fluid, help other ingredients to be evenly dispersed, and enhance the cleaning fluid's ability to dissolve a variety of pollutants; the additive propylene glycol methyl ether acetate has both non-polar and polar functional groups. These two parts not only restrict and repel each other, but also play their own inherent roles. They have a certain solubility for both non-polar and polar substances. This dual solubility allows propylene glycol methyl ether acetate to better assist in cleaning various types of pollutants during the cleaning process, while improving the fluidity and permeability of the cleaning fluid to ensure comprehensive cleaning.

[0016] The surface of the mask cleaned with the mask cleaning liquid prepared by the present invention is uniform, flat and free of visible defects, the quality and performance of the mask are significantly improved, it is no longer disturbed by pollutants, the defect rate in the photolithography manufacturing process is significantly reduced, and the generation of waste products is reduced.

[0017] Preferably, the bis-PGA-PPG grafted phosphate surfactant is prepared by the following method: 1,4-dioxacyclo-2,5-hexanedione, polypropylene glycol and tetraisopropyl titanate are mixed and heated to react to obtain a PGA-PPG polymer; diethylene glycol is added dropwise to phosphorus oxychloride and stirred to react to obtain a bisphosphate intermediate; A bisphosphate intermediate, a PGA-PPG polymer and zinc isooctanoate are added to tetrahydrofuran, heated for reaction, precipitated, filtered and dried to obtain a bisPGA-PPG grafted phosphate polymer; the bisPGA-PPG grafted phosphate polymer is added to water and stirred, then placed in a separating funnel for standing and stratification, the organic layer is mixed with an ethanol aqueous solution, the pH is adjusted to neutral, filtered, washed and dried to obtain a bisPGA-PPG grafted phosphate surfactant.

[0018] Preferably, the bis-PGA-PPG grafted phosphate surfactant is prepared by the following method: 3-8 parts by weight of 1,4-dioxacyclo-2,5-hexanedione, 10-30 parts by weight of polypropylene glycol and 0.01-0.03 parts by weight of tetraisopropyl titanate are mixed, and the mixture is reacted for 5-8 hours under nitrogen atmosphere, 100-110° C., and 100-150 r / min stirring conditions to obtain a PGA-PPG polymer; 8-12 parts by weight of diethylene glycol are added dropwise to 25-35 parts by weight of phosphorus oxychloride under nitrogen atmosphere, 3-5° C., and 100-150 r / min stirring conditions, and the addition time is 0.2-0.6 hours. After the addition is completed, the mixture is stirred and reacted for 8-10 hours to obtain a bisphosphate intermediate; 7-10 parts by weight of a bisphosphate intermediate, 25-30 parts by weight of a PGA-PPG polymer, and 0.02-0.05 parts by weight of zinc isooctanoate are added to 60-80 parts by weight of tetrahydrofuran, reacted under a nitrogen atmosphere at 50-60°C and 100-150 r / min for 1-2 hours, filtered and dried after precipitation with ether to obtain a bis-PGA-PPG grafted phosphate polymer; 20-40 parts by weight of a bis-PGA-PPG grafted phosphate polymer are added to 40-60 parts by weight of water, stirred at room temperature and 100-150 r / min for 2-4 hours, then placed in a separating funnel and allowed to stand for stratification, and the water layer is discarded, 8-12 parts by weight of the organic layer is mixed with 20-40 parts by weight of a 92-98wt% ethanol aqueous solution, the pH is adjusted to neutral, filtered, washed with anhydrous ethanol 2-5 times, and dried to obtain a bis-PGA-PPG grafted phosphate surfactant.

[0019] The present invention also provides a method for preparing the above-mentioned mask cleaning liquid, comprising the following steps: Weigh each component according to the formula, add the inorganic alkali salt into water, stir for 5-8 minutes at room temperature and 100-300r / min, then add the auxiliary agent and continue stirring for 3-5 minutes, then add the di-PGA-PPG grafted phosphate surfactant, dicetyl phosphate, and isooctyl alcohol polyoxyethylene ether phosphate, and homogenize for 1-3 minutes at 8000-12000r / min to obtain the mask cleaning solution.

[0020] Beneficial effects of the present invention: The invention provides a cleaning liquid for a mask and a preparation method thereof. By adopting a bis-PGA-PPG grafted phosphate surfactant obtained by reacting a bis-phosphate intermediate with a PGA-PPG polymer, and using it in combination with components such as an inorganic alkali salt, dicetyl phosphate, isooctyl alcohol polyoxyethylene ether phosphate and an auxiliary agent, various pollutants on the surface of the mask can be effectively removed without causing damage to the mask itself, thereby further improving the cleaning effect of the cleaning liquid for the mask, thereby extending the service life of the mask. DETAILED DESCRIPTION

[0021] The following will be combined with the specific embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] Example 1 A cleaning solution for a mask plate, comprising the following components in parts by weight: 12 parts by weight of inorganic alkali salt, 1.5 parts by weight of di-PGA-PPG grafted phosphate surfactant, 2 parts by weight of dicetyl phosphate (CAS: 2197-63-9), 1 part by weight of isooctyl alcohol polyoxyethylene ether phosphate (CAS: 68439-39-4), 3.5 parts by weight of auxiliary agent, and 130 parts by weight of deionized water. The inorganic alkali salt is sodium carbonate. The auxiliary agent is a mixture of diethylene glycol ethyl ether (CAS: 111-90-0) and propylene glycol methyl ether acetate (CAS: 108-65-6) in a weight ratio of 5:2.

[0023] The dual PGA-PPG grafted phosphate surfactant is prepared by the following method: 5.8 parts by weight of 1,4-dioxacyclo-2,5-hexanedione, 20 parts by weight of polypropylene glycol (average molecular weight of 400) and 0.026 parts by weight of tetraisopropyl titanate were mixed, and ring-opening polymerization was carried out for 6 hours under nitrogen atmosphere, 105°C, and 120 r / min stirring conditions to obtain PGA-PPG polymer; 10 parts by weight of diethylene glycol were added dropwise to 30 parts by weight of phosphorus oxychloride under nitrogen atmosphere, 4°C, and 120 r / min stirring conditions for 0.5 hours. After the addition was completed, the stirring reaction was continued for 9.5 hours to obtain a bisphosphate intermediate; 8.5 parts by weight of a bisphosphate intermediate, 26 parts by weight of a PGA-PPG polymer, and 0.035 parts by weight of zinc isooctanoate are added to 70 parts by weight of tetrahydrofuran, and the mixture is reacted under a nitrogen atmosphere at 55°C and 120 r / min for 1.5 hours. The mixture is precipitated with ether and filtered and dried to obtain a bis-PGA-PPG grafted phosphate polymer. 30 parts by weight of a bis-PGA-PPG grafted phosphate polymer are added to 50 parts by weight of water and stirred at room temperature and 120 r / min for 3 hours. The mixture is then placed in a separating funnel and allowed to stand for stratification, and the water layer is discarded. 10 parts by weight of the organic layer is mixed with 30 parts by weight of a 95wt% ethanol aqueous solution, the pH is adjusted to neutral, the mixture is filtered, washed three times with anhydrous ethanol, and dried to obtain a bis-PGA-PPG grafted phosphate surfactant.

[0024] A method for preparing a cleaning solution for a mask comprises the following steps: Weigh each component according to the formula, add the inorganic alkali salt into deionized water, stir for 6 minutes at room temperature and 200 r / min, then add the auxiliary agent and continue stirring for 4 minutes, then add the di-PGA-PPG grafted phosphate surfactant, dicetyl phosphate, and isooctyl alcohol polyoxyethylene ether phosphate, and homogenize for 2 minutes at 10000 r / min to obtain the mask cleaning solution.

[0025] Example 2 A cleaning solution for a mask plate, comprising the following components in parts by weight: 12 parts by weight of inorganic alkali salt, 1.5 parts by weight of C8-10 fatty alcohol polyoxyethylene ether phosphate monoester (CAS: 68130-47-2), 2 parts by weight of dicetyl phosphate, 1 part by weight of isooctyl alcohol polyoxyethylene ether phosphate, 3.5 parts by weight of auxiliary agent, and 130 parts by weight of deionized water. The inorganic alkali salt is sodium carbonate. The auxiliary agent is a mixture of diethylene glycol ethyl ether and propylene glycol methyl ether acetate in a weight ratio of 5:2.

[0026] A method for preparing a cleaning solution for a mask comprises the following steps: Weigh each component according to the formula, add the inorganic alkali salt into deionized water, stir for 6 minutes at room temperature and 200 r / min, then add the auxiliary agent and continue stirring for 4 minutes, then add C8-10 fatty alcohol polyoxyethylene ether phosphate monoester, dicetyl phosphate, and isooctyl alcohol polyoxyethylene ether phosphate, and homogenize at 10000 r / min for 2 minutes to obtain the mask cleaning solution.

[0027] Example 3 A cleaning solution for a mask plate, comprising the following components in parts by weight: 12 parts by weight of inorganic alkali salt, 1.5 parts by weight of di-PGA-PPG grafted phosphate surfactant, 2 parts by weight of dicetyl phosphate, 3.5 parts by weight of auxiliary agent, and 130 parts by weight of deionized water. The inorganic alkali salt is sodium carbonate. The auxiliary agent is a mixture of diethylene glycol ethyl ether and propylene glycol methyl ether acetate in a weight ratio of 5:2.

[0028] The dual PGA-PPG grafted phosphate surfactant is prepared by the following method: 5.8 parts by weight of 1,4-dioxacyclo-2,5-hexanedione, 20 parts by weight of polypropylene glycol (average molecular weight of 400) and 0.026 parts by weight of tetraisopropyl titanate were mixed, and ring-opening polymerization was carried out for 6 hours under nitrogen atmosphere, 105°C, and 120 r / min stirring conditions to obtain PGA-PPG polymer; 10 parts by weight of diethylene glycol were added dropwise to 30 parts by weight of phosphorus oxychloride under nitrogen atmosphere, 4°C, and 120 r / min stirring conditions for 0.5 hours. After the addition was completed, the stirring reaction was continued for 9.5 hours to obtain a bisphosphate intermediate; 8.5 parts by weight of a bisphosphate intermediate, 26 parts by weight of a PGA-PPG polymer, and 0.035 parts by weight of zinc isooctanoate are added to 70 parts by weight of tetrahydrofuran, and the mixture is reacted under a nitrogen atmosphere at 55°C and 120 r / min for 1.5 hours. The mixture is precipitated with ether and filtered and dried to obtain a bis-PGA-PPG grafted phosphate polymer. 30 parts by weight of a bis-PGA-PPG grafted phosphate polymer are added to 50 parts by weight of water and stirred at room temperature and 120 r / min for 3 hours. The mixture is then placed in a separating funnel and allowed to stand for stratification, and the water layer is discarded. 10 parts by weight of the organic layer is mixed with 30 parts by weight of a 95wt% ethanol aqueous solution, the pH is adjusted to neutral, the mixture is filtered, washed three times with anhydrous ethanol, and dried to obtain a bis-PGA-PPG grafted phosphate surfactant.

[0029] A method for preparing a cleaning solution for a mask comprises the following steps: Weigh each component according to the formula, add the inorganic alkali salt into deionized water, stir for 6 minutes at room temperature and 200 r / min, then add the auxiliary agent and continue stirring for 4 minutes, then add the di-PGA-PPG grafted phosphate surfactant and dicetyl phosphate, and homogenize for 2 minutes at 10000 r / min to obtain the cleaning solution for the mask.

[0030] Example 4 A cleaning solution for a mask plate, comprising the following components in parts by weight: 12 parts by weight of inorganic alkali salt, 1.5 parts by weight of di-PGA-PPG grafted phosphate surfactant, 1 part by weight of isooctyl alcohol polyoxyethylene ether phosphate, 3.5 parts by weight of auxiliary agent, and 130 parts by weight of deionized water. The inorganic alkali salt is sodium carbonate. The auxiliary agent is a mixture of diethylene glycol ethyl ether and propylene glycol methyl ether acetate in a weight ratio of 5:2.

[0031] The dual PGA-PPG grafted phosphate surfactant is prepared by the following method: 5.8 parts by weight of 1,4-dioxacyclo-2,5-hexanedione, 20 parts by weight of polypropylene glycol (average molecular weight of 400) and 0.026 parts by weight of tetraisopropyl titanate were mixed, and ring-opening polymerization was carried out for 6 hours under nitrogen atmosphere, 105°C, and 120 r / min stirring conditions to obtain PGA-PPG polymer; 10 parts by weight of diethylene glycol were added dropwise to 30 parts by weight of phosphorus oxychloride under nitrogen atmosphere, 4°C, and 120 r / min stirring conditions for 0.5 hours. After the addition was completed, the stirring reaction was continued for 9.5 hours to obtain a bisphosphate intermediate; 8.5 parts by weight of a bisphosphate intermediate, 26 parts by weight of a PGA-PPG polymer, and 0.035 parts by weight of zinc isooctanoate are added to 70 parts by weight of tetrahydrofuran, and the mixture is reacted under a nitrogen atmosphere at 55°C and 120 r / min for 1.5 hours. The mixture is precipitated with ether and filtered and dried to obtain a bis-PGA-PPG grafted phosphate polymer. 30 parts by weight of a bis-PGA-PPG grafted phosphate polymer are added to 50 parts by weight of water and stirred at room temperature and 120 r / min for 3 hours. The mixture is then placed in a separating funnel and allowed to stand for stratification, and the water layer is discarded. 10 parts by weight of the organic layer is mixed with 30 parts by weight of a 95wt% ethanol aqueous solution, the pH is adjusted to neutral, the mixture is filtered, washed three times with anhydrous ethanol, and dried to obtain a bis-PGA-PPG grafted phosphate surfactant.

[0032] A method for preparing a cleaning solution for a mask comprises the following steps: Weigh each component according to the formula, add the inorganic alkali salt into deionized water, stir for 6 minutes at room temperature and 200 r / min, then add the auxiliary agent and continue stirring for 4 minutes, then add the di-PGA-PPG grafted phosphate surfactant and isooctyl alcohol polyoxyethylene ether phosphate, and homogenize for 2 minutes at 10000 r / min to obtain the mask cleaning solution.

[0033] Example 5 A cleaning solution for a mask plate, comprising the following components in parts by weight: 12 parts by weight of inorganic alkali salt, 1.5 parts by weight of di-PGA-PPG grafted phosphate surfactant, 2 parts by weight of dicetyl phosphate, 1 part by weight of isooctyl alcohol polyoxyethylene ether phosphate, 3.5 parts by weight of auxiliary agent, and 130 parts by weight of deionized water. The inorganic alkali salt is sodium carbonate. The auxiliary agent is diethylene glycol ethyl ether.

[0034] The dual PGA-PPG grafted phosphate surfactant is prepared by the following method: 5.8 parts by weight of 1,4-dioxacyclo-2,5-hexanedione, 20 parts by weight of polypropylene glycol (average molecular weight of 400) and 0.026 parts by weight of tetraisopropyl titanate were mixed, and ring-opening polymerization was carried out for 6 hours under nitrogen atmosphere, 105°C, and 120 r / min stirring conditions to obtain PGA-PPG polymer; 10 parts by weight of diethylene glycol were added dropwise to 30 parts by weight of phosphorus oxychloride under nitrogen atmosphere, 4°C, and 120 r / min stirring conditions for 0.5 hours. After the addition was completed, the stirring reaction was continued for 9.5 hours to obtain a bisphosphate intermediate; 8.5 parts by weight of a bisphosphate intermediate, 26 parts by weight of a PGA-PPG polymer, and 0.035 parts by weight of zinc isooctanoate are added to 70 parts by weight of tetrahydrofuran, and the mixture is reacted under a nitrogen atmosphere at 55°C and 120 r / min for 1.5 hours. The mixture is precipitated with ether and filtered and dried to obtain a bis-PGA-PPG grafted phosphate polymer. 30 parts by weight of a bis-PGA-PPG grafted phosphate polymer are added to 50 parts by weight of water and stirred at room temperature and 120 r / min for 3 hours. The mixture is then placed in a separating funnel and allowed to stand for stratification, and the water layer is discarded. 10 parts by weight of the organic layer is mixed with 30 parts by weight of a 95wt% ethanol aqueous solution, the pH is adjusted to neutral, the mixture is filtered, washed three times with anhydrous ethanol, and dried to obtain a bis-PGA-PPG grafted phosphate surfactant.

[0035] A method for preparing a cleaning solution for a mask comprises the following steps: Weigh each component according to the formula, add the inorganic alkali salt into deionized water, stir for 6 minutes at room temperature and 200 r / min, then add the auxiliary agent and continue stirring for 4 minutes, then add the di-PGA-PPG grafted phosphate surfactant, dicetyl phosphate, and isooctyl alcohol polyoxyethylene ether phosphate, and homogenize for 2 minutes at 10000 r / min to obtain the mask cleaning solution.

[0036] Example 6 A cleaning solution for a mask plate, comprising the following components in parts by weight: 12 parts by weight of inorganic alkali salt, 1.5 parts by weight of di-PGA-PPG grafted phosphate surfactant, 2 parts by weight of dicetyl phosphate, 1 part by weight of isooctyl alcohol polyoxyethylene ether phosphate, 3.5 parts by weight of auxiliary agent, and 130 parts by weight of deionized water. The inorganic alkali salt is sodium carbonate. The auxiliary agent is propylene glycol methyl ether acetate.

[0037] The dual PGA-PPG grafted phosphate surfactant is prepared by the following method: 5.8 parts by weight of 1,4-dioxacyclo-2,5-hexanedione, 20 parts by weight of polypropylene glycol (average molecular weight of 400) and 0.026 parts by weight of tetraisopropyl titanate were mixed, and ring-opening polymerization was carried out for 6 hours under nitrogen atmosphere, 105°C, and 120 r / min stirring conditions to obtain PGA-PPG polymer; 10 parts by weight of diethylene glycol were added dropwise to 30 parts by weight of phosphorus oxychloride under nitrogen atmosphere, 4°C, and 120 r / min stirring conditions for 0.5 hours. After the addition was completed, the stirring reaction was continued for 9.5 hours to obtain a bisphosphate intermediate; 8.5 parts by weight of a bisphosphate intermediate, 26 parts by weight of a PGA-PPG polymer, and 0.035 parts by weight of zinc isooctanoate are added to 70 parts by weight of tetrahydrofuran, and the mixture is reacted under a nitrogen atmosphere at 55°C and 120 r / min for 1.5 hours. The mixture is precipitated with ether and filtered and dried to obtain a bis-PGA-PPG grafted phosphate polymer. 30 parts by weight of a bis-PGA-PPG grafted phosphate polymer are added to 50 parts by weight of water and stirred at room temperature and 120 r / min for 3 hours. The mixture is then placed in a separating funnel and allowed to stand for stratification, and the water layer is discarded. 10 parts by weight of the organic layer is mixed with 30 parts by weight of a 95wt% ethanol aqueous solution, the pH is adjusted to neutral, the mixture is filtered, washed three times with anhydrous ethanol, and dried to obtain a bis-PGA-PPG grafted phosphate surfactant.

[0038] A method for preparing a cleaning solution for a mask comprises the following steps: Weigh each component according to the formula, add the inorganic alkali salt into deionized water, stir for 6 minutes at room temperature and 200 r / min, then add the auxiliary agent and continue stirring for 4 minutes, then add the di-PGA-PPG grafted phosphate surfactant, dicetyl phosphate, and isooctyl alcohol polyoxyethylene ether phosphate, and homogenize for 2 minutes at 10000 r / min to obtain the mask cleaning solution.

[0039] Test Example 1 The mask cleaning solution prepared in the above-mentioned embodiments 1-6 is used to soak and clean the mask plates of the same batch to be cleaned at room temperature for 10 minutes, then rinsed with deionized water for 2 minutes after being taken out, and then blown dry with nitrogen for 1 minute. Among them, the control group uses SPM (a mixture of sulfuric acid and hydrogen peroxide) and SC1 (a mixture of ammonia water, hydrogen peroxide and water) in the prior art to clean the mask. The cleaning condition of the mask surface is observed, and the ratio of the cleaned area of ​​a single mask to the total area of ​​a single mask is greater than 95%, which is considered qualified for cleaning, and the results are statistically calculated. Mask cleaning yield = the number of masks that are qualified after one cleaning / the total number of cleaned masks × 100%.

[0040] Table 1: Cleaning effect of mask cleaning fluid Mask cleaning yield / % Mask after washing Example 1 99.25 No corrosion spots Example 2 95.10 No corrosion spots Example 3 97.21 No corrosion spots Example 4 97.08 No corrosion spots Example 5 98.02 No corrosion spots Example 6 98.27 No corrosion spots Control group 89.96 There are corrosion spots As can be seen from Table 1, compared with the control group, the cleaning effect of the cleaning liquid for the mask obtained by Examples 1-6 of the present invention is significantly improved; in particular, the mask cleaning yield corresponding to Example 1 is the highest, while Examples 2-6 do not adopt the necessary technical solutions, resulting in a decrease in the relevant performance test results. This is because the self-made double PGA-PPG grafted phosphate surfactant used in the present invention has excellent emulsification, dispersion and corrosion inhibition properties, effectively reduces the surface tension of the mask, and ensures that the pollutants are completely removed without damaging the mask; dicetyl phosphate and isooctyl alcohol polyoxyethylene ether phosphate further enhance the emulsification and dispersion ability of the cleaning liquid, and the ability to handle complex pollutants is improved. At the same time, isooctyl alcohol polyoxyethylene ether phosphate is used as an alkali-resistant penetrant to ensure efficient decontamination under alkaline conditions; the auxiliary agents diethylene glycol ethyl ether and propylene glycol methyl ether acetate further improve the fluidity and solubility of the cleaning liquid, ensuring comprehensive cleaning. The synergistic effect of each component can not only effectively remove various pollutants on the surface of the mask, but also protect the mask from damage, extend its service life, and meet the cleanliness requirements of high-precision manufacturing processes.

[0041] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A cleaning liquid for a mask, characterized in that: Made of the following components: Inorganic alkali salt, bis-PGA-PPG grafted phosphate surfactant, dicetyl phosphate, isooctyl alcohol polyoxyethylene ether phosphate, auxiliary agent and water; the bis-PGA-PPG grafted phosphate surfactant is obtained by reacting a bisphosphate intermediate with a PGA-PPG polymer.

2. The mask cleaning solution according to claim 1, wherein: The dual PGA-PPG grafted phosphate surfactant is prepared by the following method: 1,4-dioxacyclo-2,5-hexanedione, polypropylene glycol and tetraisopropyl titanate are mixed and heated to react to obtain a PGA-PPG polymer; diethylene glycol is added dropwise to phosphorus oxychloride and stirred to react to obtain a bisphosphate intermediate; the bisphosphate intermediate, PGA-PPG polymer and zinc isooctanoate are added to tetrahydrofuran, heated to react, precipitated, filtered and dried to obtain a bis-PGA-PPG grafted phosphate polymer; The bis-PGA-PPG grafted phosphate polymer is added into water and stirred, and then placed in a separatory funnel to stand and separate the layers, the organic layer is mixed with an ethanol aqueous solution, the pH is adjusted to neutral, filtered, washed, and dried to obtain a bis-PGA-PPG grafted phosphate surfactant.

3. The mask cleaning solution according to claim 1, wherein: The inorganic alkali salt is one or a mixture of two or more of sodium carbonate, potassium carbonate, sodium phosphate, potassium phosphate and sodium silicate.

4. The mask cleaning solution according to claim 1, wherein: The auxiliary agent is diethylene glycol ethyl ether and / or propylene glycol methyl ether acetate.

5. The mask cleaning solution according to claim 1, wherein: It is made of the following components in parts by weight: 5-30 parts by weight of inorganic alkali salt, 0.5-4 parts by weight of bis-PGA-PPG grafted phosphate surfactant, 0.5-6 parts by weight of dicetyl phosphate, 0.2-3 parts by weight of isooctyl alcohol polyoxyethylene ether phosphate, 1-10 parts by weight of auxiliary agent, and 50-300 parts by weight of water.

6. The mask cleaning liquid according to claim 5, characterized in that: It is made of the following components in parts by weight: 10-15 parts by weight of inorganic alkali salt, 1-2 parts by weight of bis-PGA-PPG grafted phosphate surfactant, 1-3 parts by weight of dicetyl phosphate, 0.5-1.5 parts by weight of isooctyl alcohol polyoxyethylene ether phosphate, 3-5 parts by weight of auxiliary agent, and 100-150 parts by weight of water.

7. The mask cleaning liquid according to claim 2, characterized in that: The dual PGA-PPG grafted phosphate surfactant is prepared by the following method: 3-8 parts by weight of 1,4-dioxacyclo-2,5-hexanedione, 10-30 parts by weight of polypropylene glycol and 0.01-0.03 parts by weight of tetraisopropyl titanate are mixed, and the mixture is reacted for 5-8 hours under nitrogen atmosphere, 100-110° C., and 100-150 r / min stirring conditions to obtain a PGA-PPG polymer; 8-12 parts by weight of diethylene glycol are added dropwise to 25-35 parts by weight of phosphorus oxychloride under nitrogen atmosphere, 3-5° C., and 100-150 r / min stirring conditions, and the addition time is 0.2-0.6 hours. After the addition is completed, the mixture is stirred and reacted for 8-10 hours to obtain a bisphosphate intermediate; 7-10 parts by weight of a bisphosphate intermediate, 25-30 parts by weight of a PGA-PPG polymer, and 0.02-0.05 parts by weight of zinc isooctanoate are added to 60-80 parts by weight of tetrahydrofuran, and the reaction is carried out under a nitrogen atmosphere at 50-60°C and 100-150 r / min for 1-2 hours. After precipitation with ether, the mixture is filtered and dried to obtain a bis-PGA-PPG grafted phosphate polymer. 20-40 parts by weight of a bis-PGA-PPG grafted phosphate polymer is added to 40-60 parts by weight of water, and the mixture is stirred at room temperature and 100-150 r / min for 2-4 hours. The mixture is then placed in a separating funnel and allowed to stand for stratification, and the water layer is discarded. 8-12 parts by weight of an organic layer is mixed with 20-40 parts by weight of an ethanol aqueous solution, the pH is adjusted to neutral, the mixture is filtered, the mixture is washed with anhydrous ethanol for 2-5 times, and the mixture is dried to obtain a bis-PGA-PPG grafted phosphate surfactant.

8. The mask cleaning liquid according to claim 3, characterized in that: The inorganic alkali salt is sodium carbonate.

9. The mask cleaning liquid according to claim 4, characterized in that: The auxiliary agent is a mixture of diethylene glycol ethyl ether and propylene glycol methyl ether acetate in a weight ratio of 5:1-3.

10. The method for preparing a mask cleaning solution according to any one of claims 1 to 9, characterized in that: The following steps are involved: Weigh each component according to the formula, add the inorganic alkali salt into water, stir for 5-8 minutes at room temperature and 100-300r / min, then add the auxiliary agent and continue stirring for 3-5 minutes, then add the di-PGA-PPG grafted phosphate surfactant, dicetyl phosphate, and isooctyl alcohol polyoxyethylene ether phosphate, and homogenize for 1-3 minutes at 8000-12000r / min to obtain the mask cleaning solution.