Silicon wafer texturing method

Abstract

The present invention provides a method for texturing a silicon wafer, comprising the following steps: using a first treatment liquid containing an acidic reagent, hydrogen peroxide and ozone to perform oxidation treatment on the silicon wafer to form an oxide layer on the surface of the silicon wafer to obtain a first silicon wafer intermediate; and using a texturing liquid containing a texturing additive to texturing the first silicon wafer intermediate to form a pyramid velvet surface on the surface of the first silicon wafer intermediate. The present invention can reduce the difference in specific surface area of ​​the pyramid velvet surface and improve the size uniformity of the pyramid velvet surface.

Description

Technical Field

[0001] The invention relates to the technical field of solar cells, and in particular to a method for making a silicon wafer. Background Art

[0002] The cell preparation process in heterojunction solar cells is generally: silicon wafer texturing → amorphous silicon film coating → transparent conductive film coating → screen printing. Among them, silicon wafer texturing refers to the formation of pyramid velvet on the surface of the silicon wafer. However, the specific surface area of ​​the pyramid velvet prepared by the existing method varies greatly, and the size of the pyramid velvet is uneven, which affects the subsequent coating of amorphous silicon film and transparent conductive film, and ultimately affects the performance of the cell prepared subsequently.

[0003] Since microcrystalline silicon has higher light transmittance, lower defects and higher conductivity than amorphous silicon, the coating microcrystalline technology is usually introduced into heterojunction solar cells. However, after the introduction of the coating microcrystalline technology, due to the slow deposition rate of the microcrystalline film and the poor coating uniformity, the existing silicon wafer texturing process cannot provide a very uniform pyramid texture that matches the microcrystalline film, which affects the uniformity of the subsequent coating of the microcrystalline film, thereby affecting the conversion efficiency of the subsequent prepared cells. Summary of the invention

[0004] Based on this, it is necessary to provide a method for making silicon wafers that can reduce the difference in specific surface area of ​​the pyramid velvet surface and improve the uniformity of the size of the pyramid velvet surface.

[0005] The present invention provides a method for texturing a silicon wafer, comprising the following steps:

[0006] Using a first treatment liquid containing an acidic reagent, hydrogen peroxide and ozone to perform oxidation treatment on the silicon wafer to form an oxide layer on the surface of the silicon wafer to obtain a first silicon wafer intermediate; and

[0007] The first silicon wafer intermediate is textured using a texturing liquid containing a texturing additive to form a pyramid texture surface on the surface of the first silicon wafer intermediate.

[0008] In some embodiments, the acidic reagent includes acetic acid.

[0009] In some embodiments, the method for preparing the first treatment solution comprises the following steps:

[0010] Mixing acetic acid with a concentration of 40% to 55%, hydrogen peroxide with a concentration of 30% to 40%, and water in a volume ratio of 1:(10-17):(200-210) to obtain a first treatment liquid precursor; and

[0011] introducing ozone into the first treatment liquid precursor to obtain the first treatment liquid;

[0012] Wherein, the concentration of ozone in the first treatment liquid is 45ppm-55ppm.

[0013] In some embodiments, the oxidation treatment of the silicon wafer using the first treatment solution containing an acidic reagent, hydrogen peroxide and ozone specifically includes the following steps:

[0014] adding the first treatment solution into the oxidation tank; and

[0015] The silicon wafer is placed in the first treatment liquid for oxidation treatment, and the circulation flow rate of the first treatment liquid in the oxidation tank is set to 35 L / min to 55 L / min.

[0016] In some embodiments, adding the first treatment solution into the oxidation tank specifically comprises the following steps:

[0017] A first flow balancing plate and a second flow balancing plate are provided, wherein the first flow balancing plate is provided with a plurality of first flow holes, the diameter of the first flow holes is 2 cm to 3 cm, and the second flow balancing plate is provided with a plurality of second flow holes, the diameter of the second flow holes is 0.2 cm to 0.3 cm;

[0018] Adding acetic acid and hydrogen peroxide into the oxidation tank through the first flow hole and the second flow hole in sequence;

[0019] adding water into the oxidation tank to obtain a first treatment liquid precursor; and

[0020] Ozone is added into the first treatment liquid precursor through the first flow hole and the second flow hole in sequence.

[0021] In some embodiments, the texturing method includes at least one of the following (1) to (2):

[0022] (1) The distance between two adjacent first flow holes is 7 cm to 9 cm, and the distance between two adjacent second flow holes is 0.45 cm to 0.6 cm;

[0023] (2) The first current balancing plate and the second current balancing plate are parallel, and the first current balancing plate and the second current balancing plate are perpendicular to the height direction of the oxidation tank, and the distance between the first current balancing plate and the second current balancing plate is 3 cm to 5 cm.

[0024] In some embodiments, the oxide layer has a thickness of 30 nm to 40 nm.

[0025] In some embodiments, before the silicon wafer is oxidized, the texturing method further comprises the following steps:

[0026] Roughly polishing the silicon wafer to remove a damaged layer on the surface of the silicon wafer; and

[0027] The silicon wafer after rough polishing is cleaned to remove organic matter and impurities on the silicon wafer.

[0028] In some embodiments, the method for preparing the texturing liquid comprises the following steps:

[0029] The texturing additive, alkaline reagent and water are mixed to obtain the texturing liquid.

[0030] In some embodiments, the alkaline agent includes sodium hydroxide.

[0031] The present invention uses the first treatment liquid containing an acidic reagent, hydrogen peroxide and ozone to perform oxidation treatment on the silicon wafer to form an oxide layer on the surface of the silicon wafer. The oxide layer can enhance the contact and adsorption between the silicon wafer and the texturing additive (i.e., a nucleating agent), increase the time the texturing additive is on the surface of the silicon wafer, and increase the formation time of the pyramid velvet surface, thereby reducing the difference in specific surface area of ​​the pyramid velvet surface and improving the uniformity of the size of the pyramid velvet surface, thereby improving the uniformity of subsequent microcrystalline film plating and the conversion efficiency of the subsequently prepared battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A flow chart of the texturing process of the silicon wafer provided by the present invention;

[0033] Figure 2 This is a positional relationship diagram of the first flow balancing plate, the second flow balancing plate, the oxidation tank and the liquid oxygen generator when the silicon wafer is oxidized in the present invention;

[0034] Figure 3 for Figure 2 A schematic diagram of the structure of the first current balancing plate and the isolation element;

[0035] Figure 4 for Figure 2 A schematic diagram of the structure of the second current balancing plate;

[0036] Figure 5 Acetic acid and hydrogen peroxide Figure 2 Flow direction diagram of the first flow balancing plate and the second flow balancing plate;

[0037] Figure 6 The defect ratio trend diagrams are respectively after the microcrystalline thin film is plated on the textured silicon wafer in Example 1 of the present invention and Comparative Example 1;

[0038] Figure 7 Figures showing the defect ratio after microcrystalline thin films are plated on the textured silicon wafers in Example 1 of the present invention and Comparative Example 1;

[0039] Figure 8 The graphs are of conversion efficiency after the texturing silicon wafers in Example 1 of the present invention and Comparative Example 1 are respectively made into solar cells.

[0040] Figure numerals: 10 - first flow balancing plate; 11 - first flow hole; 20 - second flow balancing plate; 21 - second flow hole; 30 - oxidation tank; 40 - ozone generator; 50 - isolation piece. DETAILED DESCRIPTION

[0041] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0043] See also Figure 1 The present invention provides a method for making a silicon wafer, comprising the following steps:

[0044] Step S11, rough polishing the silicon wafer to remove the damaged layer on the surface of the silicon wafer.

[0045] Specifically, the silicon wafer is placed in a rough polishing solution containing sodium hydroxide for rough polishing to remove a damaged layer on the surface of the silicon wafer.

[0046] Step S12: pre-cleaning the silicon wafer after rough polishing to remove organic matter and impurities on the silicon wafer.

[0047] Specifically, the silicon wafer after rough polishing is placed in a first cleaning solution containing hydrofluoric acid, hydrochloric acid and ozone for pre-cleaning to remove organic matter and metal impurities on the silicon wafer.

[0048] Step S13, pre-cleaning the silicon wafer after pre-cleaning to further remove organic matter and dirt on the silicon wafer.

[0049] Specifically, the silicon wafer after pre-cleaning is placed in a second cleaning solution containing sodium hydroxide and hydrogen peroxide for pre-cleaning to further remove organic matter and metal impurities on the silicon wafer.

[0050] Step S14, using a first treatment solution containing an acidic reagent, hydrogen peroxide and ozone to perform oxidation treatment on the pre-cleaned silicon wafer to form an oxide layer on the surface of the silicon wafer to obtain a first silicon wafer intermediate.

[0051] In one embodiment, the acidic reagent includes acetic acid.

[0052] Wherein, the oxide layer is a dense oxide layer. In one embodiment, the oxide layer has a thickness of 30 nm to 40 nm.

[0053] Specifically, acetic acid with a concentration of 40% to 55%, hydrogen peroxide with a concentration of 30% to 40%, and water are mixed in a volume ratio of 1:(10-17):(200-210) to obtain a first treatment liquid precursor, and ozone is introduced into the first treatment liquid precursor to obtain the first treatment liquid, and then the pre-cleaned silicon wafer is placed in the first treatment liquid for oxidation treatment to form the oxide layer on the surface of the silicon wafer to obtain the first silicon wafer intermediate. In one embodiment, the concentration of ozone in the first treatment liquid is 45ppm to 55ppm.

[0054] It should be noted that when preparing the first treatment liquid, it is not limited to mixing the acetic acid of the above concentration and the hydrogen peroxide of the above concentration. As long as the above first treatment liquid can be obtained, the concentration and volume of the acetic acid and hydrogen peroxide required for preparing the above first treatment liquid, as well as the volume of the above water can be changed.

[0055] See also Figures 2 to 5 More specifically, a first flow balancing plate 10 and a second flow balancing plate 20 are provided, wherein a plurality of first flow holes 11 are provided in the first flow balancing plate 10, and a plurality of second flow holes 21 are provided in the second flow balancing plate 20, acetic acid and hydrogen peroxide are sequentially added into an oxidation tank 30 having a volume of 220L to 230L through the first flow holes 11 and the second flow holes 21, and water is added into the oxidation tank 30 to obtain a first treatment liquid precursor, and liquid oxygen is passed through an ozone generator 40 to generate ozone, and the generated ozone is sequentially added into the first treatment liquid precursor through the first flow holes 11 and the second flow holes 21 to obtain the first treatment liquid, and then the pre-cleaned silicon wafer is placed in the first treatment liquid for oxidation treatment, so that the oxide layer is formed on the surface of the silicon wafer to obtain the first silicon wafer intermediate.

[0056] In one embodiment, when the silicon wafer after pre-cleaning is subjected to oxidation treatment in the first treatment solution, 50ml to 100ml of acetic acid can be added to the oxidation tank 30 each time, and 200ml to 300ml of hydrogen peroxide can be added to the oxidation tank 30 each time.

[0057] In one embodiment, when the silicon wafer after pre-cleaning is subjected to oxidation treatment in the first treatment liquid, the circulation flow rate of the first treatment liquid in the oxidation tank 30 may be 35L / min to 55L / min. Among them, appropriately increasing the circulation flow rate of the first treatment liquid in the oxidation tank 30 can improve the oxidation ability of the first treatment liquid on the silicon wafer, and is also conducive to removing the residual liquid on the silicon wafer.

[0058] In one embodiment, the oxidation tank 30 can be drained and replenished with water at a time rate of 1L to 2L per time, so as to discharge the reaction sediment at the bottom of the oxidation tank 30 in time.

[0059] See also Figure 3 and Figure 4 In one embodiment, the length of the first current balancing plate 10 is 95cm to 110cm. In one embodiment, the width of the first current balancing plate 10 is 30cm to 45cm. In one embodiment, the thickness of the first current balancing plate 10 is 1.8cm to 2.1cm. In one embodiment, the length of the second current balancing plate 20 is 95cm to 110cm. In one embodiment, the width of the second current balancing plate 20 is 30cm to 45cm. In one embodiment, the thickness of the second current balancing plate 20 is 1.8cm to 2.1cm.

[0060] In one embodiment, the diameter of each of the first circulation holes 11 is 2 cm to 3 cm. In one embodiment, the distance between two adjacent first circulation holes 11 is 7 cm to 9 cm. In one embodiment, the diameter of each of the second circulation holes 21 is 0.2 cm to 0.3 cm. In one embodiment, the distance between two adjacent second circulation holes 21 is 0.45 cm to 0.6 cm. That is, the first flow equalizing plate 10 is provided with coarse and sparse first circulation holes 11, and the second flow equalizing plate 20 is provided with fine and dense second circulation holes 21.

[0061] See also Figure 2 and Figure 5 , the first current balancing plate 10 and the second current balancing plate 20 are parallel, and the first current balancing plate 10 and the second current balancing plate 20 are perpendicular to the height direction of the oxidation tank 30. Specifically, a spacer 50 is provided between the first current balancing plate 10 and the second current balancing plate 20. In one embodiment, the thickness of the spacer 50 is 3 cm to 5 cm, so that the distance between the first current balancing plate 10 and the second current balancing plate 20 is 3 cm to 5 cm. Figure 3 As shown, the structure of the isolation member 50 is a quadrilateral with a hollow center.

[0062] Among them, the present invention releases the pressure of acetic acid and hydrogen peroxide slowly through the first equalizing plate 10, stirs ozone, acetic acid and hydrogen peroxide, and then flows out a fine and dense liquid through the second equalizing plate 20, which acts evenly on the surface of the silicon wafer, so that acetic acid, hydrogen peroxide and decomposed bubbles (i.e., ozone) pass through the second equalizing plate 20 more evenly. The double-layer equalizing plate designed by the present invention (i.e., the first equalizing plate 10 and the second equalizing plate 20) makes the oxide layer on the surface of the silicon wafer more compact and uniform, which is convenient for reducing the size difference of the pyramid velvet surface during the subsequent velvet making, improving the deposition efficiency and yield of microcrystalline thin films, improving the uniformity of coating, and improving the conversion efficiency of the subsequently prepared battery cells.

[0063] Step S15, texturing the first silicon wafer intermediate with a texturing liquid containing a texturing additive, so as to form a pyramid texture surface on the surface of the first silicon wafer intermediate, thereby obtaining a textured silicon wafer.

[0064] Specifically, the texturing additive, alkaline reagent and water are mixed to obtain the texturing liquid, and the first silicon wafer intermediate is placed in the texturing liquid for texturing to form the pyramid velvet surface on the surface of the first silicon wafer intermediate to obtain the texturing silicon wafer.

[0065] Wherein, when texturing the first silicon wafer intermediate, the texturing additive acts as a nucleating agent and is adsorbed on the surface of the oxide layer.

[0066] In one embodiment, the alkaline agent includes sodium hydroxide.

[0067] Step S16, cleaning the texturing silicon wafer to remove the residual liquid medicine on the texturing silicon wafer.

[0068] Specifically, the texturing silicon wafer is placed in a third cleaning solution containing sodium hydroxide and hydrogen peroxide for cleaning, so as to remove the residual liquid on the texturing silicon wafer.

[0069] Step S17, performing rounding treatment on the cleaned textured silicon wafer.

[0070] Specifically, the cleaned texturing silicon wafer is placed in a second treatment liquid containing hydrofluoric acid, hydrochloric acid and ozone for smoothing treatment to polish the pyramid texture surface on the surface of the texturing silicon wafer.

[0071] Step S18, passivating the textured silicon wafer after the rounding treatment.

[0072] Specifically, the textured silicon wafer after the rounding treatment is placed in a third treatment solution containing hydrofluoric acid for passivation to remove the oxide layer on the surface of the textured silicon wafer and saturate the dangling bonds on the surface of the textured silicon wafer, thereby achieving the purpose of surface passivation.

[0073] Step S19, washing the textured silicon wafer after the passivation.

[0074] Specifically, the texturing silicon wafer after the passivation is washed with water to remove the residual chemical solution on the texturing silicon wafer.

[0075] Step S20, taking out the textured silicon wafer after washing by a slow pulling device.

[0076] Specifically, the slow pulling device is used to slowly lift the washed textured silicon wafer from the water to reduce the amount of liquid adsorbed on the surface of the textured silicon wafer, and to slowly dehydrate the washed textured silicon wafer, so that the surface of the textured silicon wafer has a higher degree of cleanliness and no water marks are left on the surface.

[0077] Step S21, drying the taken out textured silicon wafer.

[0078] Specifically, the taken-out texturing silicon wafer can be dried by filling it with nitrogen.

[0079] It can be understood that after step S21, it is still necessary to coat the surface of the textured silicon wafer, such as coating a microcrystalline film, screen printing, and finally prepare a battery cell.

[0080] The present invention uses the first treatment liquid containing an acidic reagent, hydrogen peroxide and ozone to perform oxidation treatment on the silicon wafer to form an oxide layer with a thickness of 30nm to 40nm on the surface of the silicon wafer. The oxide layer can enhance the contact and adsorption between the silicon wafer and the texturing additive (i.e., nucleating agent), increase the time the texturing additive is on the surface of the silicon wafer, and increase the formation time of the pyramid velvet surface, thereby reducing the difference in specific surface area of ​​the pyramid velvet surface and improving the uniformity of the size of the pyramid velvet surface, thereby improving the uniformity of subsequent microcrystalline film plating and the conversion efficiency of the subsequently prepared battery cell.

[0081] In addition, the present invention releases the pressure of acetic acid and hydrogen peroxide slowly through the first equalizing plate 10, stirs ozone, acetic acid and hydrogen peroxide, and then flows out a fine and dense liquid through the second equalizing plate 20, which acts evenly on the surface of the silicon wafer, so that acetic acid, hydrogen peroxide and decomposed bubbles (i.e., ozone) pass through the second equalizing plate 20 more evenly. The double-layer equalizing plate designed in the present invention (i.e., the first equalizing plate 10 and the second equalizing plate 20) makes the oxide layer on the surface of the silicon wafer more compact and uniform, which is convenient for reducing the size difference of the pyramid velvet surface during the subsequent velvet making, improving the deposition efficiency and yield of the microcrystalline thin film, improving the uniformity of the coating, and improving the conversion efficiency of the subsequently prepared battery cell.

[0082] The present invention is further described below by means of specific examples and comparative examples.

[0083] Example 1

[0084] (1) Placing the silicon wafer in a rough polishing solution containing sodium hydroxide for rough polishing.

[0085] (2) The roughly polished silicon wafer is placed in a first cleaning solution containing hydrofluoric acid, hydrochloric acid and ozone for pre-cleaning.

[0086] (3) The silicon wafer after pre-cleaning is placed in a second cleaning solution containing sodium hydroxide and hydrogen peroxide for pre-cleaning.

[0087] (4) Provide a first flow balancing plate and a second flow balancing plate, wherein the first flow balancing plate is provided with a plurality of first flow holes, and the second flow balancing plate is provided with a plurality of second flow holes, and add acetic acid with a concentration of 40% and hydrogen peroxide with a concentration of 30% to an oxidation tank with a volume of 220L through the first flow holes and the second flow holes in turn, and add water to the oxidation tank, and control the volume ratio of acetic acid, hydrogen peroxide and water to be 1:10:200, to obtain a first treatment liquid precursor, and pass liquid oxygen through an ozone generator to generate ozone, and make the generated ozone be added to the first treatment liquid precursor through the first flow holes and the second flow holes in turn, to obtain a first treatment liquid, and control the concentration of ozone in the first treatment liquid to be 45ppm, and then place the pre-cleaned silicon wafer in the first treatment liquid for oxidation treatment, so that an oxide layer is formed on the surface of the silicon wafer, and obtain a first silicon wafer intermediate. Wherein, when the pre-cleaned silicon wafer is oxidized in the first treatment liquid, the circulation flow rate of the first treatment liquid in the oxidation tank is set to 35L / min. Among them, the diameter of each first flow hole is 2 cm; the distance between two adjacent first flow holes is 7 cm; the diameter of each second flow hole is 0.2 cm; the distance between two adjacent second flow holes is 0.45 cm; the first flow equalizing plate and the second flow equalizing plate are parallel, and the first flow equalizing plate and the second flow equalizing plate are both perpendicular to the height direction of the oxidation trough, and the distance between the first flow equalizing plate and the second flow equalizing plate is 3 cm.

[0088] (5) Mixing a texturing additive, sodium hydroxide and water to obtain a texturing solution, and placing a first silicon wafer intermediate in the texturing solution for texturing to form a pyramid texturing surface on the surface of the first silicon wafer intermediate to obtain a texturing silicon wafer.

[0089] (6) The textured silicon wafer is placed in a third cleaning solution containing sodium hydroxide and hydrogen peroxide for cleaning.

[0090] (7) The cleaned textured silicon wafer is placed in a second treatment liquid containing hydrofluoric acid, hydrochloric acid and ozone for smoothing.

[0091] (8) The textured silicon wafer after the rounding treatment is placed in a third treatment solution containing hydrofluoric acid for passivation.

[0092] (9) Washing the passivated silicon wafer with water.

[0093] (10) Take out the washed textured silicon wafer through a slow pulling device.

[0094] Comparative Example 1

[0095] The silicon wafer is textured using the existing method to obtain a textured silicon wafer.

[0096] (I) 1000 silicon wafers were textured according to Example 1 and Comparative Example 1, respectively, and microcrystalline films were plated on the textured silicon wafers, and the defective ratio of the microcrystalline films was tested respectively.

[0097] Among them, the defective microcrystalline film refers to the microcrystalline film being uneven and dark.

[0098] See also Figure 6 and Figure 7 , it can be seen that the defective ratio of the microcrystalline film (i.e. Figure 6 The average rate from July 2022 to September 2022 is 1.19% (i.e. Figure 7 After the improvement in the above), the microcrystalline film was plated on the textured silicon wafer prepared in Comparative Example 1, and the defective ratio of the microcrystalline film (i.e. Figure 6 The average rate from January 2022 to June 2022 is 4.85% (i.e. Figure 7 This shows that compared with Comparative Example 1, the defective ratio of the microcrystalline film coated on the textured silicon wafer prepared in Example 1 is significantly reduced (from 4.85% to 1.19%), with a reduction of up to 75.46%, indicating that the present invention can significantly reduce the difference in specific surface area of ​​the pyramid velvet surface and improve the uniformity of the size of the pyramid velvet surface, thereby improving the uniformity of the microcrystalline film.

[0099] (ii) The textured silicon wafers prepared in Example 1 and Comparative Example 1 are processed into solar cells through subsequent steps, and the conversion efficiency of the solar cells prepared from the textured silicon wafers in Example 1 and the solar cells prepared from the textured silicon wafers in Comparative Example 1 are compared.

[0100] See also Figure 8 , it can be seen that the conversion efficiency of the cell prepared by the texturing silicon wafer in Example 1 is 24.25% (i.e. Figure 8 After the improvement in the above example), the conversion efficiency of the cell prepared by the texturing silicon wafer in Comparative Example 1 is 24.01% (i.e. Figure 8 This indicates that the conversion efficiency of the cell prepared by the texturing silicon wafer in Example 1 is improved to a certain extent compared with the conversion efficiency of the cell prepared by the texturing silicon wafer in Comparative Example 1.

[0101] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0102] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for texturing a silicon wafer, characterized in that: The following steps are involved: The silicon wafer is oxidized by using a first treatment liquid containing an acidic reagent, hydrogen peroxide and ozone to form an oxide layer on the surface of the silicon wafer, wherein the thickness of the oxide layer is 30 nm to 40 nm, thereby obtaining a first silicon wafer intermediate; as well as Using a texturing liquid containing a texturing additive to texturing the first silicon wafer intermediate, so as to form a pyramid texture surface on the surface of the first silicon wafer intermediate; The oxidation treatment of the silicon wafer using the first treatment liquid containing an acidic reagent, hydrogen peroxide and ozone specifically includes the following steps: adding the first treatment liquid into an oxidation tank; and placing the silicon wafer in the first treatment liquid for oxidation treatment; wherein adding the first treatment liquid into the oxidation tank specifically includes the following steps: A first flow balancing plate and a second flow balancing plate are provided, wherein the first flow balancing plate is provided with a plurality of first flow holes, the diameter of the first flow holes is 2 cm to 3 cm, and the second flow balancing plate is provided with a plurality of second flow holes, the diameter of the second flow holes is 0.2 cm to 0.3 cm; Adding acetic acid and hydrogen peroxide into the oxidation tank through the first flow hole and the second flow hole in sequence; adding water into the oxidation tank to obtain a first treatment liquid precursor; and Ozone is added into the first treatment liquid precursor through the first flow hole and the second flow hole in sequence.

2. The method for texturing a silicon wafer as claimed in claim 1, characterized in that: The acidic reagent includes acetic acid.

3. The method for texturing a silicon wafer as claimed in claim 2, characterized in that: The method for preparing the first treatment solution comprises the following steps: Mixing acetic acid having a concentration of 40% to 55%, hydrogen peroxide having a concentration of 30% to 40%, and water in a volume ratio of 1:(10-17):(200-210) to obtain a first treatment liquid precursor; and introducing ozone into the first treatment liquid precursor to obtain the first treatment liquid; Wherein, the concentration of ozone in the first treatment liquid is 45ppm-55ppm.

4. The method for texturing a silicon wafer according to any one of claims 1 to 3, characterized in that: In the step of placing the silicon wafer in the first treatment liquid for oxidation treatment, the circulation flow rate of the first treatment liquid in the oxidation tank is set to 35 L / min to 55 L / min.

5. The method for texturing a silicon wafer according to any one of claims 1 to 3, characterized in that: The texturing method comprises at least one of the following (1) to (2): (1) The distance between two adjacent first flow holes is 7 cm to 9 cm, and the distance between two adjacent second flow holes is 0.45 cm to 0.6 cm; (2) The first current balancing plate and the second current balancing plate are parallel, and the first current balancing plate and the second current balancing plate are perpendicular to the height direction of the oxidation tank, and the distance between the first current balancing plate and the second current balancing plate is 3 cm to 5 cm.

6. The method for texturing a silicon wafer according to any one of claims 1 to 3, characterized in that: The oxide layer is a dense oxide layer.

7. The method for texturing a silicon wafer according to any one of claims 1 to 3, characterized in that: Before the silicon wafer is oxidized, the texturing method further comprises the following steps: Roughly polishing the silicon wafer to remove a damaged layer on the surface of the silicon wafer; and The silicon wafer after rough polishing is cleaned to remove organic matter and impurities on the silicon wafer.

8. The method for texturing a silicon wafer according to any one of claims 1 to 3, characterized in that: The method for preparing the texturing liquid comprises the following steps: The texturing additive, alkaline reagent and water are mixed to obtain the texturing liquid.

9. The method for texturing a silicon wafer as claimed in claim 8, characterized in that: The alkaline agent includes sodium hydroxide.

10. The method for texturing a silicon wafer according to any one of claims 1 to 3, characterized in that: After the silicon wafer is textured, the following steps are also included: The silicon wafer is cleaned, and the cleaned silicon wafer is smoothed.

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