An alkaline polishing additive for rapid polishing of single crystal silicon and a method of using the same

Abstract

The application discloses an alkali polishing additive for single crystal silicon rapid polishing and a use method thereof, relates to the field of single crystal silicon etching technology, and comprises the following components: a reaction promoter, an anti-corrosion and anti-fouling agent, a PH regulator, a defoaming agent, 1,3-bis(2-hydroxyethyl)-2-imidazolidinone, 2,5-furan dimethyl alcohol, quinoline yellow, sodium glycyrrhizinate, melamine, hydroxypropyl chitosan and deionized water. The additive has the advantages of good alkali polishing effect, high efficiency, good stability, good appearance of a polishing surface and obvious gain effect on the light conversion efficiency of a solar cell under low weight reduction.

Description

Technical Field

[0001] The present invention relates to the technical field of single crystal silicon etching, and in particular to an alkali polishing additive for rapid polishing of single crystal silicon and a use method thereof. Background Art

[0002] In the production of monocrystalline silicon solar cells, the backside of the wafers is typically subjected to an alkali polishing treatment. This treatment significantly increases the reflectivity of the backside surface, enhancing the absorption of long-wavelength light. Furthermore, the smoothness of the backside surface after alkali polishing determines the uniformity of the backside passivation film, which has a direct impact on the efficiency of the solar cell. To improve the effectiveness and efficiency of alkali polishing, the use of alkali polishing additives is essential. Their performance directly impacts the effectiveness and efficiency of alkali polishing, and thus the photovoltaic conversion efficiency and fill factor of the solar cell. Therefore, the development of alkali polishing additives with excellent overall performance and performance stability is particularly important.

[0003] Existing common alkaline polishing additives often use inorganic oxidants to increase the alkali corrosion rate of silicon, but the extent to which these substances enhance the corrosion rate is limited. On the one hand, such additives require a long reaction time, which affects production capacity. On the other hand, as clients reduce costs, the alkali concentration gradually decreases, and small black nuclei are prone to appear on the surface of the alkaline polished back, affecting performance. Conventional alkaline polishing additives often use polyol reducing agents as degassing agents to accelerate the desorption of bubbles. The oxidizing and reducing agents in the additives conflict, gradually causing chemical reactions that lead to failure. The product has a shelf life of as short as one month, and in high summer temperatures, it will expire after fifteen days. When used after such expired products, they may cause raindrop marks and an undersized tower base. Furthermore, the alkaline polishing additives on the market have more or less technical defects, such as poor stability, poor flatness, and the polishing effect at low weight loss needs to be further improved. The polishing efficiency needs to be further improved when used for alkaline polishing, and the amount of alkali used needs to be further reduced.

[0004] To address the above-mentioned issues, a Chinese invention patent application with application publication number CN117946591A discloses a single-crystal silicon alkali polishing additive, its preparation method, and polishing method. The single-crystal silicon alkali polishing additive comprises the following components by weight: 0.5% to 2% sodium metaaluminate, 2% to 4% polyvinyl alcohol, 0.5% to 3% surfactant, 1% to 3% defoamer, 0.5% to 1% isomeric alcohol oleic acid soap, and the balance is deionized water. By limiting the concentrations and amounts of each raw material, the single-crystal silicon alkali polishing additive prepared by the invention can improve the alkaline corrosion performance of alkali solution on single-crystal silicon, achieve polishing of single-crystal silicon at a relatively low weight loss, and achieve excellent flatness and reflectivity on the back side of the polished single-crystal silicon, thereby improving the conversion efficiency of solar cells. In addition, by limiting the concentrations and amounts of each substance in the single-crystal silicon alkali polishing method of the invention, rapid polishing of the single-crystal silicon is achieved with good polishing effect. However, the stability and polished surface appearance of the alkaline polishing additive need to be further improved, and the gain effect on the light conversion efficiency of solar cells needs to be further enhanced. Summary of the Invention

[0005] The main purpose of the present invention is to provide an alkali polishing additive for rapid polishing of single crystal silicon, which has good alkali polishing effect, high efficiency, good stability, good polished surface appearance, and obvious gain effect on the light conversion efficiency of solar cells, and a method for using the same.

[0006] To achieve the above objectives, the present invention provides an alkali polishing additive for rapid polishing of single crystal silicon, comprising the following components calculated by mass percentage: a reaction accelerator 0.5wt%-1wt%, a corrosion inhibitor and scale inhibitor 1wt%-3wt%, a pH regulator 2wt%-4wt%, a defoaming agent 0.05wt%-1wt%, 1,3-bis(2-hydroxyethyl)-2-imidazolidinone 0.05wt%-0.15wt%, 2,5-furan dimethanol 0.03wt%-0.12wt%, quinoline yellow 0.01wt%-0.06wt%, sodium glycyrrhizate 0.01wt%-0.05wt%, melamine 0.06wt%-0.11wt%, hydroxypropyl chitosan 0.04wt%-0.1wt%, and the balance being deionized water.

[0007] Preferably, the reaction accelerator is one or more of m-nitrophenol, sodium 3-nitrobenzoate, potassium 4-nitrobenzene sulfate, N-tert-butyloxycarbonyl-L-2-nitrophenylalanine, and 2-nitrobenzyl alcohol.

[0008] Preferably, the corrosion and scale inhibitor is one or a combination of two or more of methyl benzotriazole, benzotriazole, and citric acid.

[0009] Preferably, the pH regulator is one or a combination of formic acid, acetic acid, sodium citrate, citraconic acid, aminosulfonic acid, and methanesulfonic acid.

[0010] Preferably, the defoaming agent is one or a combination of saccharin, soluble starch, polyvinyl pyrrolidone, polyglycerol, and alkyl glycoside.

[0011] Preferably, the degree of substitution of the hydroxypropyl chitosan is ≥80.0%, and is provided by Nantong Lvshen Bioengineering Co., Ltd.

[0012] Another object of the present invention is to provide a method for using the alkali polishing additive for rapid polishing of single crystal silicon, comprising the following steps:

[0013] Step S1, uniformly mixing the components of the alkali polishing additive for rapid polishing of single crystal silicon to obtain the alkali polishing additive for rapid polishing of single crystal silicon;

[0014] Step S2, adding the alkali polishing additive for rapid polishing of single crystal silicon prepared in step S1 into the alkali solution and stirring evenly to obtain a polishing solution;

[0015] Step S3: polishing the monocrystalline silicon with the polishing liquid prepared in step S2, and then entering the subsequent solar cell preparation process to obtain a finished solar cell.

[0016] Preferably, the mass content of the alkali polishing additive for rapid polishing of single crystal silicon in the polishing liquid in step S2 is 0.3% to 1%.

[0017] Preferably, 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 3% to 6%.

[0018] Preferably, the polishing treatment in step S3 is performed at a temperature of 58 to 70° C. and for a time of 140 to 200 seconds.

[0019] Preferably, the single crystal silicon in step S3 is a 182×182 single crystal silicon wafer.

[0020] Due to the application of the above technical solution, the present invention has the following beneficial effects:

[0021] (1) The method for using the alkaline polishing additive for rapid polishing of single crystal silicon disclosed in the present invention is simple and easy to use, has low dependence on equipment, consumes less energy, has low impact on the environment, has high polishing efficiency and good effect, is suitable for continuous large-scale production, and has high promotion and application value.

[0022] (2) The alkali polishing additive for rapid polishing of single crystal silicon disclosed in the present invention comprises the following components calculated by mass percentage: reaction accelerator 0.5wt%-1wt%, corrosion inhibitor 1wt%-3wt%, pH regulator 2wt%-4wt%, defoaming agent 0.05wt%-1wt%, 1,3-bis(2-hydroxyethyl)-2-imidazolidinone 0.05wt%-0.15wt%, 2,5-furan dimethanol 0.03wt%-0.12wt%, quinoline yellow 0.01wt%-0.06wt%, sodium glycyrrhizate 0.01wt%-0.05wt%, melamine 0.06wt%-0.11wt%, hydroxypropyl chitosan 0.04wt%-0.1wt%, and the balance is deionized water. Through the mutual cooperation and joint action of the components, the product has good alkali polishing effect, high efficiency, good stability, good polishing surface appearance, and obvious gain effect on the light conversion efficiency of solar cells.

[0023] (3) The present invention discloses an alkali polishing additive for rapid polishing of single crystal silicon, wherein the reaction accelerator is one or more of m-nitrophenol, sodium 3-nitrobenzoate, potassium 4-nitrobenzene sulfate, N-tert-butyloxycarbonyl-L-2-nitrophenylalanine, and 2-nitrobenzyl alcohol; all of which contain nitro groups. The nitrogen and oxygen atoms in the nitro groups have very high electronegativity, can attract electrons, and have very strong electron-accepting ability, which can accelerate the process of silicon losing electrons to generate sodium silicate, thereby increasing the reaction rate of alkali and silicon. This electron-attracting effect can be explained by the inductive effect and the conjugated effect. The electron-withdrawing property of the nitro group affects the electron distribution and reaction activity of the entire molecule, and its ability to promote the reaction of alkali and silicon is far superior to conventional inorganic oxides; the corrosion and scale inhibitor is one or a combination of two or more of methyl benzotriazole, benzotriazole, and citric acid, which can be adsorbed on the surface of phosphosilicate glass, reducing the corrosion rate of alkali and the front side of the silicon wafer, so that the front PN junction is not destroyed during the alkali polishing process, and the back side of the battery also achieves a better polishing effect; the degassing agent is one or a combination of several of saccharin, soluble starch, polyvinyl pyrrolidone, polyglycerol, and alkyl glycoside, which can effectively reduce the surface tension of the product and accelerate the desorption of bubbles from the silicon wafer surface.

[0024] (4) The alkali polishing additive for rapid polishing of single crystal silicon disclosed in the present invention has a relatively fast alkali polishing corrosion rate, low alkali consumption, no problems such as poor edge polishing and residual black core, and sufficient stability through reasonable selection of component types and dosage ratios. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a ZETA diagram of a silicon wafer after alkali polishing using the alkali polishing additive of Example 1 of the present invention;

[0026] Figure 2 This is a ZETA diagram of a silicon wafer after alkali polishing using the alkali polishing additive of Example 2 of the present invention;

[0027] Figure 3 This is the ZETA diagram of the silicon wafer after alkali polishing using the alkali polishing additive of Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0028] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are merely examples, and those skilled in the art may conceive of other obvious variations.

[0029] Example 1, an alkaline polishing additive for rapid polishing of single crystal silicon, comprising the following components calculated in percentage by mass: a reaction accelerator 0.5 wt%, a corrosion inhibitor and scale inhibitor 1 wt%, a pH regulator 2 wt%, a defoaming agent 0.05 wt%, 1,3-bis(2-hydroxyethyl)-2-imidazolidinone 0.05 wt%, 2,5-furan dimethanol 0.03 wt%, quinoline yellow 0.01 wt%, sodium glycyrrhizate 0.01 wt%, melamine 0.06 wt%, hydroxypropyl chitosan 0.04 wt%, and the balance being deionized water.

[0030] The reaction accelerator is m-nitrophenol; the corrosion and scale inhibitor is methylbenzotriazole; the pH regulator is formic acid; the defoaming agent is saccharin; the degree of substitution of the hydroxypropyl chitosan is ≥80.0%, and it is provided by Nantong Lvshen Bioengineering Co., Ltd.

[0031] A method for using the alkali polishing additive for rapid polishing of single crystal silicon comprises the following steps:

[0032] Step S1, uniformly mixing the components of the alkali polishing additive for rapid polishing of single crystal silicon to obtain the alkali polishing additive for rapid polishing of single crystal silicon;

[0033] Step S2, adding the alkali polishing additive for rapid polishing of single crystal silicon prepared in step S1 into the alkali solution and stirring evenly to obtain a polishing solution;

[0034] Step S3: polishing the monocrystalline silicon with the polishing liquid prepared in step S2, and then entering the subsequent solar cell preparation process to obtain a finished solar cell.

[0035] The mass content of the alkali polishing additive for rapid polishing of single crystal silicon in the polishing liquid described in step S2 is 0.3%; the alkali solution described in step S2 is a sodium hydroxide solution; the mass percentage concentration of the alkali solution is 3%; the temperature of the polishing treatment in step S3 is 58°C and the time is 140s; the single crystal silicon described in step S3 is a 182×182 single crystal silicon wafer.

[0036] Example 2, an alkaline polishing additive for rapid polishing of single crystal silicon, comprising the following components calculated in mass percentage: a reaction accelerator 0.6 wt%, a corrosion inhibitor and scale inhibitor 1.5 wt%, a pH regulator 2.5 wt%, a defoaming agent 0.07 wt%, 1,3-bis(2-hydroxyethyl)-2-imidazolidinone 0.08 wt%, 2,5-furan dimethanol 0.05 wt%, quinoline yellow 0.02 wt%, sodium glycyrrhizate 0.02 wt%, melamine 0.07 wt%, hydroxypropyl chitosan 0.06 wt%, and the balance being deionized water.

[0037] The reaction accelerator is sodium 3-nitrobenzoate; the corrosion and scale inhibitor is benzotriazole; the pH regulator is acetic acid; the defoaming agent is soluble starch; the degree of substitution of the hydroxypropyl chitosan is ≥80.0%, and it is provided by Nantong Lvshen Bioengineering Co., Ltd.

[0038] A method for using the alkali polishing additive for rapid polishing of single crystal silicon comprises the following steps:

[0039] Step S1, uniformly mixing the components of the alkali polishing additive for rapid polishing of single crystal silicon to obtain the alkali polishing additive for rapid polishing of single crystal silicon;

[0040] Step S2, adding the alkali polishing additive for rapid polishing of single crystal silicon prepared in step S1 into the alkali solution and stirring evenly to obtain a polishing solution;

[0041] Step S3: polishing the monocrystalline silicon with the polishing liquid prepared in step S2, and then entering the subsequent solar cell preparation process to obtain a finished solar cell.

[0042] The mass content of the alkali polishing additive for rapid polishing of single crystal silicon in the polishing liquid described in step S2 is 0.6%; the alkali solution described in step S2 is a potassium hydroxide solution; the mass percentage concentration of the alkali solution is 4%; the temperature of the polishing treatment in step S3 is 62°C and the time is 170s; the single crystal silicon described in step S3 is a 182×182 single crystal silicon wafer.

[0043] Example 3, an alkaline polishing additive for rapid polishing of single crystal silicon, comprising the following components calculated in mass percentage: a reaction accelerator 0.8 wt%, a corrosion inhibitor and scale inhibitor 2 wt%, a pH regulator 3 wt%, a defoaming agent 0.08 wt%, 1,3-bis(2-hydroxyethyl)-2-imidazolidinone 0.1 wt%, 2,5-furan dimethanol 0.08 wt%, quinoline yellow 0.04 wt%, sodium glycyrrhizate 0.03 wt%, melamine 0.09 wt%, hydroxypropyl chitosan 0.08 wt%, and the balance being deionized water.

[0044] The reaction accelerator is potassium 4-nitrobenzene sulfate; the corrosion and scale inhibitor is citric acid; the pH regulator is sodium citrate; the defoaming agent is polyvinyl pyrrolidone; the degree of substitution of the hydroxypropyl chitosan is ≥80.0%, and it is provided by Nantong Lvshen Bioengineering Co., Ltd.

[0045] A method for using the alkali polishing additive for rapid polishing of single crystal silicon comprises the following steps:

[0046] Step S1, uniformly mixing the components of the alkali polishing additive for rapid polishing of single crystal silicon to obtain the alkali polishing additive for rapid polishing of single crystal silicon;

[0047] Step S2, adding the alkali polishing additive for rapid polishing of single crystal silicon prepared in step S1 into the alkali solution and stirring evenly to obtain a polishing solution;

[0048] Step S3: polishing the monocrystalline silicon with the polishing liquid prepared in step S2, and then entering the subsequent solar cell preparation process to obtain a finished solar cell.

[0049] The mass content of the alkali polishing additive for rapid polishing of single crystal silicon in the polishing liquid described in step S2 is 0.8%; the alkali solution described in step S2 is a sodium hydroxide solution; the mass percentage concentration of the alkali solution is 4.5%; the temperature of the polishing treatment in step S3 is 64°C and the time is 180s; the single crystal silicon described in step S3 is a 182×182 single crystal silicon wafer.

[0050] Example 4, an alkaline polishing additive for rapid polishing of single crystal silicon, comprising the following components calculated in mass percentage: a reaction accelerator 0.9 wt%, a corrosion inhibitor and scale inhibitor 2.5 wt%, a pH regulator 3.5 wt%, a defoaming agent 0.09 wt%, 1,3-bis(2-hydroxyethyl)-2-imidazolidinone 0.13 wt%, 2,5-furan dimethanol 0.1 wt%, quinoline yellow 0.05 wt%, sodium glycyrrhizate 0.04 wt%, melamine 0.1 wt%, hydroxypropyl chitosan 0.09 wt%, and the balance being deionized water.

[0051] The reaction accelerator is a mixture of m-nitrophenol, sodium 3-nitrobenzoate, potassium 4-nitrobenzene sulfate, N-tert-butyloxycarbonyl-L-2-nitrophenylalanine, and 2-nitrobenzyl alcohol in a mass ratio of 1:1:2:2:3; the corrosion and scale inhibitor is a mixture of methylbenzotriazole, benzotriazole, and citric acid in a mass ratio of 1:3:5; the pH regulator is a mixture of formic acid, acetic acid, sodium citrate, citraconic acid, aminosulfonic acid, and methylsulfonic acid in a mass ratio of 1:1:1:1:3:2; the defoaming agent is a mixture of saccharin, soluble starch, polyvinylpyrrolidone, polyglycerol, and alkyl glycoside in a mass ratio of 1:3:2:2:1; the degree of substitution of the hydroxypropyl chitosan is ≥80.0%, and it is provided by Nantong Lvshen Bioengineering Co., Ltd.

[0052] A method for using the alkali polishing additive for rapid polishing of single crystal silicon comprises the following steps:

[0053] Step S1, uniformly mixing the components of the alkali polishing additive for rapid polishing of single crystal silicon to obtain the alkali polishing additive for rapid polishing of single crystal silicon;

[0054] Step S2, adding the alkali polishing additive for rapid polishing of single crystal silicon prepared in step S1 into the alkali solution and stirring evenly to obtain a polishing solution;

[0055] Step S3: polishing the monocrystalline silicon with the polishing liquid prepared in step S2, and then entering the subsequent solar cell preparation process to obtain a finished solar cell.

[0056] The mass content of the alkali polishing additive for rapid polishing of single crystal silicon in the polishing liquid described in step S2 is 0.9%; the alkali solution described in step S2 is a sodium hydroxide solution; the mass percentage concentration of the alkali solution is 5.5%; the temperature of the polishing treatment in step S3 is 68°C and the time is 190s; the single crystal silicon described in step S3 is a 182×182 single crystal silicon wafer.

[0057] Example 5, an alkaline polishing additive for rapid polishing of single crystal silicon, comprising the following components calculated in mass percentage: a reaction accelerator 1 wt%, a corrosion inhibitor and scale inhibitor 3 wt%, a pH regulator 4 wt%, a defoaming agent 1 wt%, 1,3-bis(2-hydroxyethyl)-2-imidazolidinone 0.15 wt%, 2,5-furan dimethanol 0.12 wt%, quinoline yellow 0.06 wt%, sodium glycyrrhizate 0.05 wt%, melamine 0.11 wt%, hydroxypropyl chitosan 0.1 wt%, and the balance being deionized water.

[0058] The reaction accelerator is 2-nitrobenzyl alcohol; the corrosion and scale inhibitor is methylbenzotriazole; the pH regulator is citraconic acid; the defoaming agent is alkyl glycoside; the degree of substitution of the hydroxypropyl chitosan is ≥80.0%, and it is provided by Nantong Lvshen Bioengineering Co., Ltd.

[0059] A method for using the alkali polishing additive for rapid polishing of single crystal silicon comprises the following steps:

[0060] Step S1, uniformly mixing the components of the alkali polishing additive for rapid polishing of single crystal silicon to obtain the alkali polishing additive for rapid polishing of single crystal silicon;

[0061] Step S2, adding the alkali polishing additive for rapid polishing of single crystal silicon prepared in step S1 into the alkali solution and stirring evenly to obtain a polishing solution;

[0062] Step S3: polishing the monocrystalline silicon with the polishing liquid prepared in step S2, and then entering the subsequent solar cell preparation process to obtain a finished solar cell.

[0063] The mass content of the alkali polishing additive for rapid polishing of single crystal silicon in the polishing liquid described in step S2 is 1%; the alkali solution described in step S2 is sodium hydroxide solution or potassium hydroxide solution; the mass percentage concentration of the alkali solution is 6%; the temperature of the polishing treatment in step S3 is 70°C and the time is 200s; the single crystal silicon described in step S3 is 182×182 single crystal silicon wafer.

[0064] Comparative Example 1

[0065] The present invention provides an alkali polishing additive for rapid polishing of single crystal silicon and a method for using the same, which is similar to Example 1, except that 1,3-bis(2-hydroxyethyl)-2-imidazolidinone and sodium glycyrrhizate are not added.

[0066] Comparative Example 2

[0067] The present invention provides an alkali polishing additive for rapid polishing of single crystal silicon and a method for using the same, which is similar to Example 1, except that 2,5-furan dimethanol and hydroxypropyl chitosan are not added.

[0068] Comparative Example 3

[0069] The present invention provides an alkali polishing additive for rapid polishing of single crystal silicon and a method for using the same, which is similar to Example 1, except that quinoline yellow and melamine are not added.

[0070] The alkali polishing additives for rapid polishing of single crystal silicon involved in the above Examples 1-5 and Comparative Examples 1-3 were subjected to relevant performance tests. The test results are shown in Table 1. The test method is as follows:

[0071] (1) Appearance: Observe the appearance changes of the silicon wafer after polishing. If the tower base has high flatness, a fused tower base, and no black core, the appearance passes. If there are raindrop marks, poor tower base flatness, an independent tower base, or any of the following conditions, the appearance fails.

[0072] (2) Reflectivity and weight loss: Use a reflectivity test system to measure the integrated reflectivity within the wavelength range of 300-1100nm; count and calculate the weight loss;

[0073] (3) Stability: The additives prepared in each example were placed at room temperature for 6 months, and samples were taken to test the reflectivity again according to the method in (2), and the reflectivity retention rate was calculated. The larger the value, the better the stability.

[0074] (4) Electrical performance: The finished solar cells of each case were tested using a dedicated test instrument for solar cells, such as a single flash simulator; the test conditions were standard test conditions (STC): light intensity 1000W / m 2 ; Spectrum AM1.5; Temperature 25℃; Test method is in accordance with IEC904-1, main electrical performance parameters of the cell: Photoelectric conversion efficiency (Eta, unit: %).

[0075] At the same time, taking Example 1, Example 2 and Comparative Example 1 as examples, the ZETA diagrams of the silicon wafers after alkali polishing using the alkali polishing additives of each example are as follows: Figure 1 、 Figure 2 、 Figure 3 shown; from Figure 1-Figure 3 It can be seen that the product of the embodiment of the present invention has a better appearance after alkali polishing.

[0076] Table 1

[0077]

[0078] As can be seen from Table 1, the alkali polishing additive for rapid polishing of single crystal silicon disclosed in the embodiment of the present invention has a more excellent low-weight-loss alkali polishing effect compared with the comparative example product, a better photoelectric conversion efficiency gain effect on solar cell wafers, higher stability and reflectivity, and a better appearance of the polished silicon wafer; the addition of 1,3-bis(2-hydroxyethyl)-2-imidazolidinone, sodium glycyrrhizate, 2,5-furan dimethanol, hydroxypropyl chitosan, quinoline yellow and melamine is beneficial to improving the above properties.

[0079] 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 to the above embodiments. The above embodiments and descriptions merely illustrate the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. An alkali polishing additive for rapid polishing of single crystal silicon, characterized in that: The invention comprises the following components calculated by mass percentage: reaction accelerator 0.5wt%-1wt%, corrosion inhibitor and scale inhibitor 1wt%-3wt%, pH regulator 2wt%-4wt%, defoaming agent 0.05wt%-1wt%, 1,3-bis(2-hydroxyethyl)-2-imidazolidinone 0.05wt%-0.15wt%, 2,5-furan dimethanol 0.03wt%-0.12wt%, quinoline yellow 0.01wt%-0.06wt% t%, 0.01wt%-0.05wt% of sodium glycyrrhizate, 0.06wt%-0.11wt% of melamine, 0.04wt%-0.1wt% of hydroxypropyl chitosan, and the balance being deionized water; the reaction accelerator is one or more of m-nitrophenol, sodium 3-nitrobenzoate, potassium 4-nitrobenzene sulfate, N-tert-butyloxycarbonyl-L-2-nitrophenylalanine, and 2-nitrobenzyl alcohol; and the degree of substitution of the hydroxypropyl chitosan is ≥80.0%.

2. The alkali polishing additive for rapid polishing of single crystal silicon according to claim 1, characterized in that: The corrosion and scale inhibitor is one of methyl benzotriazole, benzotriazole and citric acid, or a combination of two or more thereof.

3. The alkali polishing additive for rapid polishing of single crystal silicon according to claim 1, characterized in that: The pH regulator is one or a combination of formic acid, acetic acid, sodium citrate, citraconic acid, aminosulfonic acid, and methanesulfonic acid.

4. The alkali polishing additive for rapid polishing of single crystal silicon according to claim 1, characterized in that: The defoaming agent is one or a combination of saccharin, soluble starch, polyvinyl pyrrolidone, decaglycerol, and alkyl glycoside.

5. A method for using the alkali polishing additive for rapid polishing of single crystal silicon according to any one of claims 1 to 4, characterized in that: The steps include: Step S1, uniformly mixing the components of the alkali polishing additive for rapid polishing of single crystal silicon to obtain the alkali polishing additive for rapid polishing of single crystal silicon; Step S2, adding the alkali polishing additive for rapid polishing of single crystal silicon prepared in step S1 into the alkali solution and stirring evenly to obtain a polishing solution; Step S3: polishing the monocrystalline silicon with the polishing liquid prepared in step S2, and then entering the subsequent solar cell preparation process to obtain a finished solar cell.

6. The method for using the alkali polishing additive for rapid polishing of single crystal silicon according to claim 5, characterized in that: The mass content of the alkali polishing additive for rapid polishing of single crystal silicon in the polishing liquid in step S2 is 0.3% to 1%; the alkali solution in step S2 is sodium hydroxide solution or potassium hydroxide solution; the mass percentage concentration of the alkali solution is 3% to 6%.

7. The method for using the alkali polishing additive for rapid polishing of single crystal silicon according to claim 5, characterized in that: The polishing process in step S3 is performed at a temperature of 58 to 70° C. and for a time of 140 to 200 seconds.

8. The method for using the alkali polishing additive for rapid polishing of single crystal silicon according to claim 5, characterized in that: The single crystal silicon in step S3 is a 182×182 single crystal silicon wafer.

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