A texturing additive for improving the appearance and efficiency of HJT cells and its usage method

Abstract

A texturing additive for improving the appearance and efficiency of HJT cells and its usage method, which relates to the technical field of semiconductor etching texturing, includes the following components: a surface nucleating agent, a defoaming agent, a dispersant, a surfactant, 1,3,5-tris(2-hydroxyethyl) cyanuric acid, 2-(2-hydroxyethyl) guanidine, glycerophosphorylcholine, sodium camphorsulfonate, hyperbranched polyglycidol, and deionized water. This additive has good texturing effect and high efficiency under low weight loss, can effectively improve the appearance of HJT cell texturing, and increase the cell efficiency and fill factor of HJT cells.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor etching and texturing, and particularly to a texturing additive for improving the appearance of HJT cell texturing and enhancing efficiency and its usage method. Background Art

[0002] In the HJT cell manufacturing process, there is a rough polishing process in the cleaning and texturing process that is different from the perc / TopCon technology. After rough polishing, the surface of the silicon wafer is flat. When using ordinary texturing additives on the market for texturing, due to the insufficient adsorption capacity of the texturing additive, the pyramids on the textured surface are uneven, resulting in a decrease in the fill factor; at the same time, the two sides of the silicon wafer are not fully textured due to being blocked by the clamping teeth of the carrier, which will cause obvious carrier clamping tooth marks on the silicon wafer, ultimately resulting in a significant increase in the appearance defect rate. In addition, the texturing additives on the market also more or less have technical defects such as long texturing time, large texturing weight loss, low efficiency of HJT cells manufactured in the HJT cell manufacturing process, and insufficient fill factor.

[0003] To solve the above problems, the Chinese invention patent with the authorization announcement number CN111326410B discloses an anti-carrier mark texturing solution for HIT cells and its texturing method. The texturing solution includes, by weight percentage, 0.1 - 5% of an anti-carrier mark texturing additive, 0 - 0.5% of an auxiliary texturing agent, 0.1 - 0.8% of a pH buffer, and the balance is an alkaline solution. This invention is applicable to the HIT cell texturing process, overcomes the defects in the existing HIT texturing technology such as low production capacity, the use of a large amount of isopropanol, and easy appearance defects such as carrier marks, and thus has the advantages of preventing defects such as carrier marks and bubble columns during the texturing of silicon wafers. At the same time, the size of the pyramids after texturing by this invention reaches 5 - 12um. On the premise of maintaining large pyramids, the texturing time of the silicon wafer is effectively shortened, and the single-tank production capacity is improved. In addition, it also has the advantages of reducing the weight loss of the silicon wafer during texturing, reducing the alkali consumption, and extending the service life of the texturing solution. However, the cell efficiency and fill factor of the HIT cells textured by this texturing solution still need to be further improved. Summary of the Invention

[0004] The main purpose of the present invention is to provide a texturing additive for improving the appearance of HJT cell texturing and enhancing efficiency and its usage method, which has good texturing effect and high efficiency under low weight loss, can effectively improve the appearance of HJT cell texturing, and improve the cell efficiency and fill factor of HJT cells.

[0005] To achieve the above objectives, the present invention provides a texturing additive for improving the appearance of HJT cell texturing and enhancing efficiency, which comprises the following components by mass percentage: 0.5 wt% - 1 wt% of a surface nucleating agent, 0.5 wt% - 4 wt% of a defoaming agent, 0.02 wt% - 2 wt% of a dispersant, 0.1 wt% - 1 wt% of a surfactant, 0.08 wt% - 0.15 wt% of 1,3,5-tris(2-hydroxyethyl) cyanuric acid, 0.01 wt% - 0.1 wt% of 2-(2-hydroxyethyl) guanidine, 0.03 wt% - 0.12 wt% of glycerophosphorylcholine, 0.08 wt% - 0.15 wt% of sodium camphorsulfonate, 0.1 wt% - 0.3 wt% of hyperbranched polyglycidol, and the balance is deionized water.

[0006] Preferably, the surface nucleating agent is one or a combination of two or more of 2-hydroxypropyl-β-cyclodextrin, 2-hydroxy-7-naphthalenesulfonic acid sodium salt, and sodium dodecylbenzenesulfonate.

[0007] Preferably, the defoaming agent is one or a combination of two or more of chitosan, lily polysaccharide, alkyl polyglycoside, and grifola frondosa polysaccharide.

[0008] Preferably, the dispersant is one or a combination of two of sodium methylnaphthalenesulfonate and sodium methylene bisnaphthalenesulfonate.

[0009] Preferably, the surfactant is one or a combination of two of sodium dodecyl sulfate and octylphenol polyoxyethylene ether.

[0010] Preferably, there is no special requirement for the source of the hyperbranched polyglycidol. In an embodiment of the present invention, the preparation method of the hyperbranched polyglycidol refers to the preparation method of hPG-1 in the reference: Wang Zongsheng, Li Shaolu, Zhang Keming, Hu Yunxia. Synthesis and properties of hyperbranched polyglycidol [J]. Journal of Functional Polymers, 2019, 32(4): 507 - 512.

[0011] Another objective of the present invention is to provide a method for using the texturing additive for improving the appearance of HJT cell texturing and enhancing efficiency, which comprises the following steps:

[0012] Step S1: After uniformly mixing the components of the texturing additive for improving the appearance of HJT cell texturing and enhancing efficiency, a texturing additive for improving the appearance of HJT cell texturing and enhancing efficiency is obtained;

[0013] Step S2: Add the texturing additive for improving the appearance of HJT cell texturing and enhancing efficiency prepared in step S1 to the lye and stir evenly to obtain a texturing solution;

[0014] Step S3: Place the cut thin monocrystalline silicon wafer in a rough polishing tank to remove the damaged layer by rough polishing. The solution in the rough polishing tank is a 1-2 wt% sodium hydroxide solution, the rough polishing time is 90-120 s, and the rough polishing temperature is 70-80 °C; then place the cut monocrystalline silicon wafer in a pre-hydrogen peroxide tank for pre-cleaning, and then place it in deionized water to clean the silicon wafer;

[0015] Step S4: Immerse the silicon wafer processed in Step S3 in the texturing solution for texturing;

[0016] Step S5: Clean the silicon wafer textured in Step S4 successively with deionized water, alkaline solution of hydrogen peroxide, deionized water, acid cleaning, and deionized water; then immerse it in deionized water at 85 °C and slowly lift it out, and place the textured monocrystalline silicon wafer in a drying oven to dry.

[0017] Preferably, in Step S2, the mass ratio of the texturing additive to the alkaline solution is (0.35-0.6):100.

[0018] Preferably, in Step S2, the alkaline solution is a sodium hydroxide solution or a potassium hydroxide solution; the mass percentage concentration of the alkaline solution is 0.5% to 2%.

[0019] Preferably, in Step S3, the pre-hydrogen peroxide tank contains a pre-prepared cleaning solution, and the cleaning solution is a mixed aqueous solution of hydrogen peroxide and sodium hydroxide, where the mass percentage concentration of hydrogen peroxide is 1% to 4%, and the mass percentage concentration of sodium hydroxide is 0.1% to 0.4%.

[0020] Preferably, in Step S3, the temperature of the pre-cleaning is 55-65 °C, and the time is 100-150 s.

[0021] Preferably, in Step S4, the temperature of the texturing is 80-85 °C, and the texturing time is 420-520 s.

[0022] Preferably, in Step S5, the alkaline solution of hydrogen peroxide is an aqueous solution of potassium hydroxide containing hydrogen peroxide, where the mass percentage concentration of hydrogen peroxide is 1-4%, and the mass percentage concentration of potassium hydroxide is 0.1-0.4%.

[0023] Preferably, in Step S5, the temperature of the alkaline solution cleaning of hydrogen peroxide is 55-65 °C, and the time is 100-150 s.

[0024] Preferably, in Step S5, the acid used for the acid cleaning is hydrofluoric acid or hydrochloric acid with a concentration of 1-4 mol / L.

[0025] Preferably, in Step S5, the cleaning time of the acid cleaning is 90-180 s, and the temperature is 23-30 °C.

[0026] Due to the application of the above technical solution, the present invention has the following beneficial effects:

[0027] (1) The method for using the texturing additive for improving the texturing appearance and efficiency of HJT cells disclosed by the present invention has a simple process, convenient operation control, low dependence on equipment and labor intensity, little environmental impact, good texturing effect, high texturing efficiency, is suitable for continuous large-scale production, and has high popularization and application value.

[0028] (2) The texturing additive for improving the texturing appearance and efficiency of HJT cells disclosed by the present invention includes the following components calculated by mass percentage: 0.5wt%-1wt% of surface nucleating agent, 0.5wt%-4wt% of defoaming agent, 0.02wt%-2wt% of dispersant, 0.1wt%-1wt% of surfactant, 0.08wt%-0.15wt% of 1,3,5-tris(2-hydroxyethyl) cyanuric acid, 0.01wt%-0.1wt% of 2-(2-hydroxyethyl) guanidine, 0.03wt%-0.12wt% of glycerophosphorylcholine, 0.08wt%-0.15wt% of sodium camphorsulfonate, 0.1wt%-0.3wt% of hyperbranched polyglycidol, and the balance is deionized water. Through the mutual cooperation and joint action of each component, the prepared texturing additive for improving the texturing appearance and efficiency of HJT cells has good texturing effect and high efficiency under low weight loss, can effectively improve the texturing appearance of HJT cells, and improve the cell efficiency and fill factor of HJT cells; compared with the traditional HJT texturing additive, this additive has the advantages of good appearance after texturing, no flower basket tooth marks, uniform pyramidal texture on the surface, and less broken fluff.

[0029] (3) The texturing additive for improving the texturing appearance and efficiency of HJT cells disclosed by the present invention can greatly increase the dispersion effect of the texturing additive in the texturing tank by reasonably selecting the types and dosage ratios of the components, make the additive more evenly adsorbed on the surface of the silicon wafer, and make the part blocked by the teeth of the flower basket fully react, so as to obtain a more uniform surface texture and eliminate the flower basket tooth marks. At the same time, it can also achieve a good texturing effect with less addition amount, reduce the weight loss caused by excessive isotropic etching while ensuring the formation of the pyramidal surface texture, that is, complete the formation of the pyramid under low weight loss, which is beneficial to cost reduction and efficiency improvement. Description of the Drawings

[0030] Figure 1 SEM image of the surface of the silicon wafer after texturing in Example 1 of the present invention.

[0031] Figure 2 SEM image of the surface of the silicon wafer after texturing in Example 2 of the present invention.

[0032] Figure 3 SEM image of the surface of the silicon wafer after texturing in Comparative Example 1 of the present invention. Detailed implementation manners

[0033] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments in the following description are only examples, and other obvious variations can be conceived by those skilled in the art.

[0034] Example 1, a texturing additive for improving the appearance and efficiency of HJT cell texturing, comprising the following components by mass percentage: texturing nucleating agent 0.5 wt%, defoaming agent 0.5 wt%, dispersant 0.02 wt%, surfactant 0.1 wt%, 1,3,5-tris(2-hydroxyethyl) cyanuric acid 0.08 wt%, 2-(2-hydroxyethyl) guanidine 0.01 wt%, glycerophosphorylcholine 0.03 wt%, sodium camphorsulfonate 0.08 wt%, hyperbranched polyglycidol 0.1 wt%, and the balance is deionized water.

[0035] The texturing nucleating agent is 2-hydroxypropyl-β-cyclodextrin; the defoaming agent is chitosan; the dispersant is sodium methylnaphthalenesulfonate; the surfactant is sodium dodecyl sulfate; the preparation method of the hyperbranched polyglycidol refers to the preparation method of hPG-1 in the reference, and the reference is: Wang Zongsheng, Li Shaolu, Zhang Keming, Hu Yunxia. Synthesis and properties of hyperbranched polyglycidol [J]. Journal of Functional Polymers, 2019, 32(4): 507-512.

[0036] A method for using the texturing additive for improving the appearance and efficiency of HJT cell texturing comprises the following steps:

[0037] Step S1, after mixing the components of the texturing additive for improving the appearance and efficiency of HJT cell texturing evenly, a texturing additive for improving the appearance and efficiency of HJT cell texturing is obtained;

[0038] Step S2, adding the texturing additive for improving the appearance and efficiency of HJT cell texturing prepared in step S1 into the alkali solution and stirring evenly to obtain a texturing solution;

[0039] Step S3, placing the cut thin monocrystalline silicon wafer in a rough polishing tank to remove the damaged layer by rough polishing. The solution in the rough polishing tank is 1 wt% sodium hydroxide solution, the rough polishing time is 90 s, and the rough polishing temperature is 70 °C; then placing the cut monocrystalline silicon wafer in a pre-oxidation tank for pre-cleaning, and then placing it in deionized water to clean the silicon wafer;

[0040] Step S4, immersing the silicon wafer processed in step S3 in the texturing solution for texturing;

[0041] Step S5: The silicon wafers after texturing in step S4 are successively cleaned with deionized water, cleaned with an alkaline solution of hydrogen peroxide, cleaned with deionized water, acid-cleaned, and cleaned with deionized water; then immersed in deionized water at 85°C and slowly lifted out, and the textured crystalline silicon wafers are placed in a drying oven for drying.

[0042] In step S2, the mass ratio of the texturing additive to the alkaline solution is 0.35:100; the alkaline solution in step S2 is a sodium hydroxide solution; the mass percentage concentration of the alkaline solution is 0.5%.

[0043] In step S3, the pre-hydrogen peroxide tank contains a pre-prepared cleaning solution, and the cleaning solution is a mixed aqueous solution of hydrogen peroxide and sodium hydroxide, where the mass percentage concentration of hydrogen peroxide is 1% and the mass percentage concentration of sodium hydroxide is 0.1%; the temperature of the pre-cleaning in step S3 is 55°C and the time is 100 s.

[0044] In step S4, the temperature of the texturing is 80°C and the texturing time is 420 s; the alkaline solution of hydrogen peroxide in step S5 is an aqueous potassium hydroxide solution containing hydrogen peroxide, where the mass percentage concentration of hydrogen peroxide is 1% and the mass percentage concentration of potassium hydroxide is 0.1%; the temperature of the alkaline solution cleaning of hydrogen peroxide in step S5 is 55°C and the time is 100 s; the acid used for the acid cleaning in step S5 is hydrofluoric acid with a concentration of 1 mol / L; the cleaning time of the acid cleaning in step S5 is 90 s and the temperature is 23°C.

[0045] Example 2, a texturing additive for improving the appearance and efficiency of HJT cell texturing, comprising the following components calculated by mass percentage: 0.6 wt% of a surface nucleating agent, 1.5 wt% of a defoaming agent, 0.2 wt% of a dispersant, 0.3 wt% of a surfactant, 0.1 wt% of 1,3,5-tris(2-hydroxyethyl) cyanuric acid, 0.03 wt% of 2-(2-hydroxyethyl) guanidine, 0.05 wt% of glycerophosphorylcholine, 0.1 wt% of sodium camphorsulfonate, 0.15 wt% of hyperbranched polyglycidol, and the balance is deionized water.

[0046] The surface nucleating agent is 2-hydroxy-7-naphthalenesulfonic acid sodium salt; the defoaming agent is lily polysaccharide; the dispersant is sodium methylene bisnaphthalenesulfonate; the surfactant is octylphenol polyoxyethylene ether; the preparation method of the hyperbranched polyglycidol refers to the preparation method of hPG-1 in the reference, and the reference is: Wang Zongsheng, Li Shaolu, Zhang Keming, Hu Yunxia. Synthesis and properties of hyperbranched polyglycidol [J]. Journal of Functional Polymers, 2019, 32(4): 507-512.

[0047] A method for using the texturing additive for improving the appearance and efficiency of HJT cell texturing comprises the following steps:

[0048] Step S1: After uniformly mixing each component of the texturing additive for improving the appearance and efficiency of HJT cell texturing, a texturing additive for improving the appearance and efficiency of HJT cell texturing is obtained.

[0049] Step S2: Add the texturing additive for improving the appearance and efficiency of HJT cell texturing prepared in Step S1 to the lye and stir evenly to obtain a texturing solution.

[0050] Step S3: Place the cut thin monocrystalline silicon wafer in a rough polishing tank to remove the damaged layer by rough polishing. The solution in the rough polishing tank is a 1.2 wt% sodium hydroxide solution, the rough polishing time is 100 s, and the rough polishing temperature is 73 °C. Then place the cut monocrystalline silicon wafer in a pre-double oxygen water tank for pre-cleaning, and then place it in deionized water to clean the silicon wafer.

[0051] Step S4: Immerse the silicon wafer processed in Step S3 in the texturing solution for texturing.

[0052] Step S5: Wash the silicon wafer textured in Step S4 successively with deionized water, alkaline solution of hydrogen peroxide, deionized water, acid cleaning, and deionized water. Then immerse it in deionized water at 85 °C and slowly lift it out, and place the textured monocrystalline silicon wafer in a drying oven to dry.

[0053] In Step S2, the mass ratio of the texturing additive to the lye is 0.4:100; the lye in Step S2 is a potassium hydroxide solution; the mass percentage concentration of the lye is 0.9%.

[0054] In Step S3, the pre-double oxygen water tank contains a pre-prepared cleaning solution, which is a mixed aqueous solution of hydrogen peroxide and sodium hydroxide. The mass percentage concentration of hydrogen peroxide is 2%, and the mass percentage concentration of sodium hydroxide is 0.2%; the temperature of the pre-cleaning in Step S3 is 57 °C, and the time is 110 s.

[0055] In Step S4, the temperature of the texturing is 81 °C, and the texturing time is 440 s; the alkaline solution of hydrogen peroxide in Step S5 is an aqueous solution of potassium hydroxide containing hydrogen peroxide, where the mass percentage concentration of hydrogen peroxide is 2%, and the mass percentage concentration of potassium hydroxide is 0.2%; the temperature of the alkaline solution cleaning of hydrogen peroxide in Step S5 is 57 °C, and the time is 120 s; the acid used for acid cleaning in Step S5 is hydrochloric acid with a concentration of 2 mol / L; the cleaning time of the acid cleaning in Step S5 is 110 s, and the temperature is 25 °C.

[0056] Example 3. A texturing additive for improving the appearance and efficiency of HJT cells, comprising the following components by mass percentage: 0.75 wt% of a surface nucleating agent, 2.5 wt% of a defoaming agent, 0.12 wt% of a dispersant, 0.6 wt% of a surfactant, 0.11 wt% of 1,3,5-tris(2-hydroxyethyl) cyanuric acid, 0.06 wt% of 2-(2-hydroxyethyl) guanidine, 0.08 wt% of glycerophosphorylcholine, 0.11 wt% of sodium camphorsulfonate, 0.2 wt% of hyperbranched polyglycidol, and the balance being deionized water.

[0057] The surface nucleating agent is sodium dodecylbenzenesulfonate; the defoaming agent is alkyl polyglycoside; the dispersant is sodium methylnaphthalenesulfonate; the surfactant is sodium dodecyl sulfate; the preparation method of the hyperbranched polyglycidol refers to the preparation method of hPG-1 in the reference, and the reference is: Wang Zongsheng, Li Shaolu, Zhang Keming, Hu Yunxia. Synthesis and properties of hyperbranched polyglycidol [J]. Journal of Functional Polymers, 2019, 32(4): 507-512.

[0058] A method for using the texturing additive for improving the appearance and efficiency of HJT cells, comprising the following steps:

[0059] Step S1. After mixing the components of the texturing additive for improving the appearance and efficiency of HJT cells evenly, a texturing additive for improving the appearance and efficiency of HJT cells is obtained;

[0060] Step S2. Add the texturing additive for improving the appearance and efficiency of HJT cells prepared in Step S1 to the alkali solution and stir evenly to obtain a texturing solution;

[0061] Step S3. Place the cut thin monocrystalline silicon wafer in a rough polishing tank to remove the damaged layer by rough polishing. The solution in the rough polishing tank is a 1.5 wt% sodium hydroxide solution, the rough polishing time is 105 s, and the rough polishing temperature is 75 °C; then place the cut monocrystalline silicon wafer in a pre-oxidation tank for pre-cleaning, and then place it in deionized water to clean the silicon wafer;

[0062] Step S4. Immerse the silicon wafer processed in Step S3 in the texturing solution for texturing;

[0063] Step S5. Wash the silicon wafer textured in Step S4 successively with deionized water, with an alkali solution of hydrogen peroxide, with deionized water, with acid, and with deionized water; then immerse it in deionized water at 85 °C and slowly lift it out, and place the textured monocrystalline silicon wafer in a drying oven to dry.

[0064] In step S2, the mass ratio of the texturing additive to the lye is 0.5:100; the lye in step S2 is a potassium hydroxide solution; the mass percentage concentration of the lye is 1.3%; in step S3, the pre-double hydrogen peroxide tank contains a pre-prepared cleaning solution, and the cleaning solution is a mixed aqueous solution of hydrogen peroxide and sodium hydroxide, wherein the mass percentage concentration of hydrogen peroxide is 2.5% and the mass percentage concentration of sodium hydroxide is 0.25%; the temperature of the pre-cleaning in step S3 is 60°C and the time is 130 s.

[0065] In step S4, the temperature of the texturing is 83°C and the texturing time is 480 s; in step S5, the alkaline solution of hydrogen peroxide is an aqueous potassium hydroxide solution containing hydrogen peroxide, wherein the mass percentage concentration of hydrogen peroxide is 2.5% and the mass percentage concentration of potassium hydroxide is 0.25%; the temperature of the cleaning with the alkaline solution of hydrogen peroxide in step S5 is 60°C and the time is 130 s; the acid used for the acid cleaning in step S5 is hydrofluoric acid with a concentration of 2.5 mol / L; the cleaning time of the acid cleaning in step S5 is 130 s and the temperature is 26°C.

[0066] Example 4, a texturing additive for improving the appearance and efficiency of HJT cell texturing, comprising the following components by mass percentage: 0.9 wt% of a surface nucleating agent, 3.5 wt% of a defoaming agent, 0.18 wt% of a dispersant, 0.9 wt% of a surfactant, 0.13 wt% of 1,3,5-tris(2-hydroxyethyl) cyanuric acid, 0.09 wt% of 2-(2-hydroxyethyl) guanidine, 0.1 wt% of glycerophosphorylcholine, 0.13 wt% of sodium camphorsulfonate, 0.25 wt% of hyperbranched polyglycidol, and the balance is deionized water.

[0067] The surface nucleating agent is a mixture of 2-hydroxypropyl-β-cyclodextrin, 2-hydroxy-7-naphthalenesulfonic acid sodium salt, and sodium dodecylbenzenesulfonate in a mass ratio of 1:2:3; the defoaming agent is a mixture of chitosan, lily polysaccharide, alkyl polyglycoside, and grifola frondosa polysaccharide in a mass ratio of 1:1:3:1; the dispersant is a mixture of sodium methylnaphthalenesulfonate and sodium methylene bisnaphthalenesulfonate in a mass ratio of 3:5; the surfactant is a mixture of sodium dodecyl sulfate and octylphenol polyoxyethylene ether in a mass ratio of 1:3; the preparation method of the hyperbranched polyglycidol refers to the preparation method of hPG-1 in the reference, and the reference is: Wang Zongsheng, Li Shaolu, Zhang Keming, Hu Yunxia. Synthesis and properties of hyperbranched polyglycidol [J]. Journal of Functional Polymers, 2019, 32(4): 507-512.

[0068] A method for using the texturing additive for improving the appearance and efficiency of HJT cell texturing includes the following steps:

[0069] Step S1: After uniformly mixing each component of the texturing additive for improving the appearance and efficiency of HJT cell texturing, a texturing additive for improving the appearance and efficiency of HJT cell texturing is obtained;

[0070] Step S2: Add the texturing additive for improving the appearance and efficiency of HJT cell texturing prepared in Step S1 to the lye and stir well to obtain a texturing solution;

[0071] Step S3: Place the cut thin monocrystalline silicon wafer in a rough polishing tank to remove the damaged layer by rough polishing. The solution in the rough polishing tank is a 1.8 wt% sodium hydroxide solution, the rough polishing time is 110 s, and the rough polishing temperature is 78 °C; then place the cut monocrystalline silicon wafer in a pre-double oxygen water tank for pre-cleaning, and then place it in deionized water to clean the silicon wafer;

[0072] Step S4: Immerse the silicon wafer processed in Step S3 in the texturing solution for texturing;

[0073] Step S5: Wash the silicon wafer textured in Step S4 successively with deionized water, alkaline solution of hydrogen peroxide, deionized water, acid cleaning, and deionized water; then immerse it in deionized water at 85 °C and slowly lift it out, and place the textured monocrystalline silicon wafer in a drying oven to dry.

[0074] In Step S2, the mass ratio of the texturing additive to the lye is 0.55:100; the lye in Step S2 is a sodium hydroxide solution; the mass percentage concentration of the lye is 1.8%; in Step S3, the pre-double oxygen water tank contains a pre-prepared cleaning solution, and the cleaning solution is a mixed aqueous solution of hydrogen peroxide and sodium hydroxide, where the mass percentage concentration of hydrogen peroxide is 3.5% and the mass percentage concentration of sodium hydroxide is 0.35%; the temperature of the pre-cleaning in Step S3 is 63 °C and the time is 140 s.

[0075] In Step S4, the temperature of the texturing is 84 °C and the texturing time is 510 s; in Step S5, the alkaline solution of hydrogen peroxide is an aqueous potassium hydroxide solution containing hydrogen peroxide, where the mass percentage concentration of hydrogen peroxide is 3.5% and the mass percentage concentration of potassium hydroxide is 0.35%; the temperature of the alkaline solution of hydrogen peroxide cleaning in Step S5 is 63 °C and the time is 140 s; the acid used for acid cleaning in Step S5 is hydrochloric acid with a concentration of 3.5 mol / L; the cleaning time of the acid cleaning in Step S5 is 170 s and the temperature is 29 °C.

[0076] Example 5. A texturing additive for improving the appearance and efficiency of HJT cells, comprising the following components by mass percentage: 1 wt% of a surface nucleating agent, 4 wt% of a defoaming agent, 2 wt% of a dispersant, 1 wt% of a surfactant, 0.15 wt% of 1,3,5-tris(2-hydroxyethyl) cyanuric acid, 0.1 wt% of 2-(2-hydroxyethyl) guanidine, 0.12 wt% of glycerophosphorylcholine, 0.15 wt% of sodium camphorsulfonate, 0.3 wt% of hyperbranched polyglycidol, and the balance being deionized water.

[0077] The surface nucleating agent is 2-hydroxypropyl-β-cyclodextrin; the defoaming agent is Grifola frondosa polysaccharide; the dispersant is sodium methylnaphthalene sulfonate; the surfactant is octylphenol polyoxyethylene ether; the preparation method of the hyperbranched polyglycidol refers to the preparation method of hPG-1 in the reference, and the reference is: Wang Zongsheng, Li Shaolu, Zhang Keming, Hu Yunxia. Synthesis and properties of hyperbranched polyglycidol [J]. Journal of Functional Polymers, 2019, 32(4): 507-512.

[0078] A method for using the texturing additive for improving the appearance and efficiency of HJT cells, comprising the following steps:

[0079] Step S1. After mixing the components of the texturing additive for improving the appearance and efficiency of HJT cells evenly, a texturing additive for improving the appearance and efficiency of HJT cells is obtained.

[0080] Step S2. Add the texturing additive for improving the appearance and efficiency of HJT cells prepared in Step S1 to the lye and stir evenly to obtain a texturing solution.

[0081] Step S3. Place the cut thin monocrystalline silicon wafer in a rough polishing tank to remove the damaged layer by rough polishing. The solution in the rough polishing tank is 2 wt% sodium hydroxide solution, the rough polishing time is 120 s, and the rough polishing temperature is 80 °C; then place the cut monocrystalline silicon wafer in a pre-oxidation tank for pre-cleaning, and then place it in deionized water to clean the silicon wafer.

[0082] Step S4. Immerse the silicon wafer treated in Step S3 in the texturing solution for texturing.

[0083] Step S5. Wash the silicon wafer textured in Step S4 successively with deionized water, alkaline solution of hydrogen peroxide, deionized water, acid cleaning, and deionized water; then immerse it in deionized water at 85 °C and slowly lift it out, and place the textured monocrystalline silicon wafer in a drying oven for drying.

[0084] In step S2, the mass ratio of the texturing additive to the alkali solution is 0.6:100; the alkali solution described in step S2 is a sodium hydroxide solution; the mass percentage concentration of the alkali solution is 2%; in step S3, the pre-double hydrogen peroxide tank contains a pre-prepared cleaning solution, and the cleaning solution is a mixed aqueous solution of hydrogen peroxide and sodium hydroxide, where the mass percentage concentration of hydrogen peroxide is 4% and the mass percentage concentration of sodium hydroxide is 0.4%; in step S3, the temperature of the pre-cleaning is 65°C and the time is 150 s; in step S4, the temperature of the texturing is 85°C and the texturing time is 520 s.

[0085] In step S5, the alkali solution of hydrogen peroxide is an aqueous potassium hydroxide solution containing hydrogen peroxide, where the mass percentage concentration of hydrogen peroxide is 4% and the mass percentage concentration of potassium hydroxide is 0.4%; in step S5, the temperature of the cleaning with the alkali solution of hydrogen peroxide is 65°C and the time is 150 s; the acid used in the acid cleaning in step S5 is hydrofluoric acid with a concentration of 4 mol / L; the cleaning time of the acid cleaning in step S5 is 180 s and the temperature is 30°C.

[0086] Comparative Example 1

[0087] The present invention provides a texturing additive for improving the appearance and efficiency of HJT cell texturing and its use method, which is similar to Example 1, except that 1,3,5-tris(2-hydroxyethyl) cyanuric acid and hyperbranched polyglycidol are not added.

[0088] Comparative Example 2

[0089] The present invention provides a texturing additive for improving the appearance and efficiency of HJT cell texturing and its use method, which is similar to Example 1, except that 2-(2-hydroxyethyl) guanidine and camphorsulfonic acid sodium are not added.

[0090] Perform relevant performance tests on the texturing additives for improving the appearance and efficiency of HJT cell texturing involved in the above Examples 1-5 and Comparative Examples 1-2. The test results are shown in Table 1, and the test methods are as follows:

[0091] (1) Put the polished crystalline silicon wafers of each example into the subsequent solar cell preparation process to make finished HJT cell wafers. The electrical performance parameters of the cell wafers are tested using a special test instrument for solar cell wafers, such as a single flash simulator; the test conditions are standard test conditions (STC): light intensity 1000 W / m 2 ; spectral AM1.5; temperature 25°C; the test method is carried out in accordance with IEC904-1. The main electrical performance parameters of the cell wafers are: photoelectric conversion efficiency (Eta, unit: %), fill factor (FF, unit: %).

[0092] (2) Statistically calculate the weight loss after texturing of the products of each example.

[0093] Taking Example 1, Example 2 and Comparative Example 1 as examples, the surface of the silicon wafer after texturing treatment was observed by scanning electron microscopy, as Figures 1 - 3 , from Figures 1 - 3 It can be seen that the appearance of the product in the embodiment of the present invention is better after texturing, without the tooth marks of the flower basket being stuck, the pyramid of the velvet surface is more uniform, and there is less broken velvet.

[0094] Table 1

[0095]

[0096] As can be seen from Table 1, the texturing additive for improving the texturing appearance and efficiency of HJT cells disclosed in the embodiments of the present invention has a more excellent texturing effect with lower weight loss compared with the products of the comparative examples, and the fill factor and photoelectric conversion efficiency of the fabricated HJT cells are higher; the addition of 1,3,5-tris(2-hydroxyethyl) cyanuric acid, hyperbranched polyglycidol, 2-(2-hydroxyethyl) guanidine and sodium camphorsulfonate is beneficial to improving the above properties.

[0097] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments, and the principles described in the above embodiments and the specification are only the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A texturing additive for improving the texturing appearance and efficiency of HJT batteries, characterized in that: The invention comprises the following components calculated by mass percentage: 0.5wt%-1wt% of a velvet nucleating agent, 0.5wt%-4wt% of a defoaming agent, 0.02wt%-2wt% of a dispersing agent, 0.1wt%-1wt% of a surfactant, 0.08wt%-0.15wt% of 1,3,5-tris(2-hydroxyethyl)cyanuric acid, 0.01wt%-0.1wt% of 2-(2-hydroxyethyl)guanidine, 0.03wt%-0.12wt% of glycerolphosphorylcholine, 0.08wt%-0.15wt% of sodium camphorsulfonate, 0.1wt%-0.3wt% of hyperbranched polyglycidol, and the balance is deionized water; the velvet nucleating agent is one or a combination of two or more of 2-hydroxypropyl-β-cyclodextrin, sodium 2-hydroxy-7-naphthalenesulfonate, and sodium dodecylbenzenesulfonate; the defoaming agent is one or a combination of two or more of chitosan, lily polysaccharide, alkyl glycoside, and maitake mushroom polysaccharide.

2. The texturing additive for improving the texturing appearance and improving the efficiency of HJT batteries according to claim 1, characterized in that: The dispersant is one of sodium methyl naphthalene sulfonate and sodium methylene bisnaphthalene sulfonate or a combination of the two; the surfactant is one of sodium dodecyl sulfate and octylphenol polyoxyethylene ether or a combination of the two.

3. A method for using the texturing additive for improving the texturing appearance and efficiency of HJT batteries according to any one of claims 1-2, characterized in that: The steps include: Step S1, after uniformly mixing the various components of the texturing additive for improving the texturing appearance and efficiency of HJT batteries, a texturing additive for improving the texturing appearance and efficiency of HJT batteries is obtained; Step S2, adding the texturing additive prepared in step S1 for improving the texturing appearance and efficiency of HJT battery into the alkali solution and stirring evenly to obtain a texturing solution; Step S3, placing the cut thin single crystal silicon wafer in a rough polishing tank for rough polishing to remove the damaged layer, the solution in the rough polishing tank is 1-2wt% sodium hydroxide solution, the rough polishing time is 90-120s, and the rough polishing temperature is 70-80°C; then placing the cut single crystal silicon wafer in a front hydrogen peroxide tank for pre-cleaning, and then placing it in deionized water to clean the silicon wafer; Step S4, immersing the silicon wafer processed in step S3 into a texturing solution for texturing; Step S5, sequentially wash the silicon wafer after the texturing in step S4 with deionized water, alkaline solution of hydrogen peroxide, deionized water, acid, and deionized water; then immerse it in deionized water at 85°C and slowly pull it out, and place the texturing crystalline silicon wafer in a drying oven for drying.

4. The method for using the texturing additive for improving the texturing appearance and efficiency of HJT batteries according to claim 3, characterized in that: The mass ratio of the texturing additive and the alkali solution in step S2 is (0.35-0.6):100; the alkali solution in step S2 is a sodium hydroxide solution or a potassium hydroxide solution; the mass percentage concentration of the alkali solution is 0.5% to 2%.

5. The method for using the texturing additive for improving the texturing appearance and efficiency of HJT batteries according to claim 3, characterized in that: The front hydrogen peroxide tank in step S3 contains a pre-prepared cleaning solution, which is a mixed aqueous solution of hydrogen peroxide and sodium hydroxide, wherein the mass percentage concentration of hydrogen peroxide is 1% to 4%, and the mass percentage concentration of sodium hydroxide is 0.1% to 0.4%.

6. The method for using the texturing additive for improving the texturing appearance and efficiency of HJT batteries according to claim 3, characterized in that: The pre-cleaning temperature in step S3 is 55-65°C, and the time is 100-150s; the texturing temperature in step S4 is 80-85°C, and the texturing time is 420-520s.

7. The method for using the texturing additive for improving the texturing appearance and efficiency of HJT batteries according to claim 3, characterized in that: The alkaline solution of hydrogen peroxide in step S5 is a potassium hydroxide aqueous solution containing hydrogen peroxide, wherein the mass percentage concentration of hydrogen peroxide is 1-4%, and the mass percentage concentration of potassium hydroxide is 0.1-0.4%.

8. The method for using the texturing additive for improving the texturing appearance and efficiency of HJT batteries according to claim 3, characterized in that: The cleaning temperature of the hydrogen peroxide alkaline solution in step S5 is 55-65° C. and the cleaning time is 100-150 seconds.

9. The method for using the texturing additive for improving the texturing appearance and efficiency of HJT batteries according to claim 3, characterized in that: The acid used for the acid cleaning in step S5 is hydrofluoric acid or hydrochloric acid with a concentration of 1-4 mol / L; the cleaning time of the acid cleaning in step S5 is 90-180s, and the temperature is 23-30°C.

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