Over-etching reworking method and solar cell

Abstract

The invention relates to an over-etching reworking method and a solar cell. The over-etching reworking method comprises the following steps: detecting a cell piece after a preset solar cell preparation process; collecting the over-etched to-be-reworked battery piece according to a detection result; re-texturing the other surface, opposite to the over-facet surface of the to-be-reworked battery piece, of the to-be-reworked battery piece; the over-etching surface of the to-be-reworked battery piece is an etching surface of which the actual etching depth is greater than the target etching depth in the to-be-reworked battery piece. As the to-be-reworked battery piece does not need to be cleaned, and the other surface, opposite to the over-facet surface, of the to-be-reworked battery piece is directly textured again, on one hand, gram weight loss caused by cleaning of a reworking cleaning machine to the battery piece can be avoided, on the other hand, only one surface is textured, and the gram weight loss caused by texturing can be further reduced. The influence caused by over-etching of the to-be-reworked battery piece can be compensated through a subsequent conventional solar battery preparation process, and the quality of a solar battery finished product is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of solar cell over-etching and reworking, and in particular to an over-etching and reworking method and a solar cell. Background Art

[0002] During the solar cell manufacturing process, a chain machine is required for the post-diffusion de-coating process. During the BSG (Borosilicate Glass) / PSG (Phosphosilicate Glass) removal process, abnormalities such as water film coverage integrity, roller leveling, automation and roller linkage stoppage, and abnormal machine stoppage are inevitable. Such problems will cause the water film to fall off during the BSG / PSG removal process of the silicon wafer, causing the chemical solution to adhere and cause over-engraving on the surface. After the material is intercepted, the appearance is abnormal and it cannot be transferred normally, requiring rework.

[0003] Currently, most rework processes involve first passing the material through a rework cleaning machine and then re-texturing, which results in a large weight loss, thinner silicon wafers, and more fragments. Furthermore, the material is not successfully intercepted and flows into the screen process, causing the EL (Electroluminescence) edge to become black, affecting the EL pass rate and efficiency. Summary of the Invention

[0004] Based on this, it is necessary to provide an over-engraving rework method and a solar cell that can reduce the weight loss caused by the rework process in order to address the above technical problems.

[0005] In a first aspect, the present application provides an over-etching rework method, the over-etching rework method comprising:

[0006] Testing the solar cells after the preset solar cell preparation process;

[0007] Collect the over-engraved cells to be reworked based on the test results;

[0008] The other side of the cell to be reworked opposite to the over-etched facet of the cell to be reworked is re-textured; the over-etched facet of the cell to be reworked is an etched face of the cell to be reworked where the actual etching depth is greater than the target etching depth.

[0009] In one embodiment, re-texturing the other side of the cell to be reworked opposite to the over-engraved side of the cell to be reworked comprises:

[0010] Place the over-engraved surface of the cell to be reworked toward the bottom of the wet process basket;

[0011] The other side of the cell to be reworked located in the wet process basket and opposite to the over-engraved side is re-textured.

[0012] In one embodiment, the overetch rework method further comprises:

[0013] Performing boron diffusion on the cell to be reworked to form a borosilicate glass layer on the surface of the overcut facet;

[0014] Removing the borosilicate glass layer from the cell to be reworked in the wet process basket;

[0015] A first etching and polishing process is performed on the overcut facet of the cell to be reworked after the borosilicate glass layer is removed.

[0016] In one embodiment, the step of removing the borosilicate glass layer from the cell to be reworked in the wet process basket includes:

[0017] The borosilicate glass layer on the surface of the overcut facet in the cell to be reworked in the wet process basket is brought into contact with an acidic solution, so that the acidic solution corrodes the borosilicate glass layer formed on the surface of the overcut facet.

[0018] In one embodiment, the first etching and polishing process is performed on the overcut facet of the cell to be reworked after the borosilicate glass layer is removed, comprising:

[0019] The overcut facet of the cell to be reworked after the borosilicate glass layer is removed is brought into contact with an alkaline solution, so that the alkaline solution performs a first etching and polishing on the overcut facet of the cell to be reworked.

[0020] In one embodiment, the overetch rework method further comprises:

[0021] Before replacing the texturing solution, the other side of the cell to be reworked, which is opposite to the over-engraved side of the cell to be reworked, is texturing again.

[0022] In one embodiment, the preset solar cell preparation process includes:

[0023] contacting the back side of the cell with an alkaline solution so that the alkaline solution performs a second etching and polishing treatment on the back side of the cell; the back side of the cell is the side not provided with a borosilicate glass layer;

[0024] Among them, when the battery cell is the battery cell to be reworked after inspection, the front side of the battery cell is the over-engraved surface of the reworked battery cell; the front side of the battery cell is opposite to the back side of the battery cell, and the borosilicate glass layer is provided on the front side of the battery cell.

[0025] In one embodiment, the preset solar cell preparation process includes:

[0026] contacting the front surface of the cell with an alkaline solution so that the alkaline solution removes a damaged layer on the front surface of the cell generated in a previous solar cell manufacturing process; the front surface of the cell is the side without a tunneling oxide layer;

[0027] Among them, when the battery cell is the battery cell to be reworked after inspection, the back side of the battery cell is the over-engraved surface of the reworked battery cell; the back side of the battery cell is opposite to the front side of the battery cell, and the back side of the battery cell is provided with the tunneling oxide layer.

[0028] In a second aspect, the present application further provides a solar cell prepared by the above-mentioned over-etching rework method.

[0029] In one embodiment, the solar cell comprises a TOPCon cell.

[0030] The above-mentioned over-engraving rework method and solar cell, the over-engraving rework method includes testing the cell after the preset solar cell preparation process; collecting the over-engraved cell to be reworked according to the test results; re-texturing the other side of the cell to be reworked that is opposite to the over-engraved surface of the cell to be reworked; the over-engraved surface of the cell to be reworked is the etched surface in the cell to be reworked where the actual etching depth is greater than the target etching depth. The over-engraving rework method in this application does not require cleaning the cell to be reworked, and directly re-textures the other side of the cell to be reworked that is opposite to the over-engraved surface. On the one hand, it can avoid the weight loss of the cell caused by the rework cleaning machine, and on the other hand, only one side is velveted, which can further reduce the weight loss caused by texturing. In addition, the influence of over-engraving in the cell to be reworked can be compensated by the subsequent conventional solar cell preparation process, so that the performance of the solar cell product finally prepared remains unchanged, ensuring the quality of the solar cell product. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present application or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 FIG1 is a flow chart of an over-etching rework method in one embodiment;

[0033] Figure 2 Schematic diagram of a process of re-texturing the other side of the reworked battery cell opposite to the over-engraved side of the reworked battery cell in one embodiment;

[0034] Figure 3FIG2 is a second flow chart of an over-etching rework method in one embodiment;

[0035] Figure 4 This is the third flow chart of the over-etching rework method in one embodiment. DETAILED DESCRIPTION

[0036] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0037] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0038] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0039] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0040] In one embodiment, Figure 1 As shown, attached Figure 1A flowchart of a method for reworking an overetching process in one embodiment of the present application is shown. This embodiment illustrates the method as applied to a terminal. It is understood that the method can also be applied to a server, or to a system comprising a terminal and a server, and implemented through interaction between the terminal and the server. In this embodiment, the overetching rework method includes the following steps: S101 to S103.

[0041] Step S101 : testing the solar cell after the preset solar cell manufacturing process.

[0042] The preset solar cell manufacturing process may be any process that may cause over-etching of the cell, for example, a process of removing a borosilicate glass layer or a process of removing a phosphosilicate glass layer, but is not limited thereto.

[0043] Specifically, the inspection of the cells after the preset solar cell preparation process can be performed by technicians or machines, mainly by detecting whether the cells are over-etched.

[0044] For example, the color difference on the surface of the cell may be detected. If the color difference on the surface of the cell reaches a target level, it indicates that the preset solar cell manufacturing process has caused over-etching on the cell.

[0045] As another example, the electrical performance of the cell after the preset solar cell preparation process can be tested. If the electrical performance parameters of the cell, such as open circuit voltage, short circuit current, etc., are lower than normal values, it means that the preset solar cell preparation process has caused over-etching of the cell.

[0046] Step S102: collecting over-etched cells to be reworked according to the detection results.

[0047] The test result can reflect whether the cell is over-etched, and corresponds to the method used to test the cell in step S101. For example, if the cell surface appearance is tested, the corresponding test result may be that the color difference of the cell surface has reached the target level. Another example is that if the cell electrical performance is tested, the corresponding test result may be that the cell electrical performance parameters are below normal values, without limitation.

[0048] Specifically, collecting over-engraved battery cells to be reworked according to the detection results refers to uniformly collecting a certain number of over-engraved battery cells to be reworked into a preset container, so as to rework a certain number of battery cells to be reworked at the same time to ensure the rework efficiency.

[0049] Step S103 , re-texturing the other side of the reworked cell opposite to the over-etched facet of the reworked cell; the over-etched facet of the reworked cell is the etched face of the reworked cell where the actual etching depth is greater than the target etching depth.

[0050] In step S103, the two sides of the reworked cell have different etching conditions. The side with an actual etching depth greater than the target etching depth is an over-etched facet. The side opposite the over-etched facet can be understood as the polished surface, i.e., the base surface of the cell (silicon wafer). The over-etched facet is originally an oxide layer, so it is difficult to produce a textured surface during the re-texturing process. Therefore, directly texturing the over-etched cell to be reworked can also achieve normal texture on one side. Further, through the conventional solar cell preparation process after texturing, the oxide layer on the over-etched facet can be removed, avoiding abnormal appearance without causing any abnormality in the final solar cell product.

[0051] In order to verify the technical effect of the present application, the inventors conducted the following tests: the solar cells prepared by the over-etching rework method in the present application were used as a control group, and the control group was compared with normal cells, cells produced at the same time on the production line, and cells processed by a rework cleaning machine, and the conversion efficiency, pass rate, suede effect, SPC data (SPC data: data used to monitor and analyze the cell production process in Statistical Process Control) and weight loss of the solar cells in the control group were tested respectively.

[0052] Table 1 Comparison of SPC data between the control group and the normal group after the alkali polishing process after texturing

[0053]

[0054] It can be seen that there is no difference in SPC data between the control group after the alkali polishing process and the normal group.

[0055] Table 2 Comparison of suede effect between control group and normal piece

[0056]

[0057] It can be seen that compared with normal cells, after the control group was re-textured using the over-engraving rework method in this application, there was basically no difference between the velvet produced on the other side of the reworked cell opposite to the over-engraved surface and the velvet of the normal cell.

[0058] Table 3 Comparison of conversion efficiency and first pass rate of cells in the control group and production line at the same time

[0059]

[0060] It can be seen that compared with the battery cells produced on the same period of the production line, there is no abnormality in the photoelectric conversion efficiency and pass rate of the comparison group.

[0061] Table 4 Comparison of weight loss of the control group and the cells processed by the rework cleaning machine

[0062]

[0063] It can be seen that compared with the weight loss of the battery cell after being processed by the rework cleaning machine, the weight loss of the battery cell processed by the over-engraving rework method of the present application is obviously lower.

[0064] The over-engraving rework method in this embodiment does not require cleaning of the reworked cell. Instead, the other side of the reworked cell opposite the over-engraved side is re-textured. This avoids weight loss caused by the rework cleaning machine. Furthermore, since only one side is velvet-treated, weight loss due to texturization is further reduced. Furthermore, the effects of over-engraving on the reworked cell can be compensated for through subsequent conventional solar cell production steps, ensuring the performance of the final solar cell product remains unchanged and the quality of the finished solar cell product is guaranteed.

[0065] In one embodiment, see the attached Figure 2 , attached Figure 2 A schematic diagram of the process of re-texturing the other side of the battery cell to be reworked opposite to the over-engraved surface of the battery cell to be reworked in one embodiment of the present application is shown. In this embodiment, the re-texturing of the other side of the battery cell to be reworked opposite to the over-engraved surface of the battery cell to be reworked includes the following steps S201 to S202.

[0066] Step S201: Place the over-engraved surface of the cell to be reworked toward the bottom of the wet process basket.

[0067] Among them, the wet flower basket refers to the container or tool used in wet processing processes such as battery cell cleaning and texturing, which is used to load and fix the battery cells to ensure uniform treatment in the chemical solution.

[0068] Step S202 , re-texturing the other side of the cell to be reworked located in the wet process basket and opposite to the over-engraved facet.

[0069] In this embodiment, by placing the over-engraved facet of the cell to be reworked toward the bottom of the wet-process basket, on the one hand, it is possible to ensure that the other side of the cell to be reworked, which is opposite the over-engraved facet, fully reacts with the texturing solution, ensuring that the texturing of the other side of the cell to be reworked, which is opposite the over-engraved facet, is properly produced. On the other hand, it helps to fully remove the over-engraved facet in the cell to be reworked during subsequent processes such as borosilicate glass layer removal and alkaline polishing after texturing, ensuring that the cell to be reworked has no abnormal appearance after being treated by the over-engraved rework method of this application.

[0070] In one embodiment, see the attached Figure 3 , attached Figure 3 The second flow chart of the over-etching rework method in one embodiment of the present application is shown. The over-etching rework method in this embodiment also includes the following steps S301 to S303.

[0071] In step S301 , the cell to be reworked is subjected to boron diffusion to form a borosilicate glass layer on the surface of the facet.

[0072] Step S302 , removing the borosilicate glass layer from the cell to be reworked in the wet process basket.

[0073] Step S303 , performing a first etching and polishing process on the overcut facet of the cell to be reworked after the borosilicate glass layer is removed.

[0074] Among them, steps S301 to S303 in this embodiment can be understood as a subsequent process synchronized with the solar cell preparation production line after the reworked cell is re-textured. At this time, the over-engraved surface of the cell to be reworked after the borosilicate glass layer is removed is subjected to a first corrosion polishing treatment, which can eliminate the over-engraving effect caused by the over-engraved surface in the preset solar cell preparation process, so that the original color difference of the over-engraved surface can be eliminated, ensuring that there is basically no difference between the over-engraved reworked cell and the normal solar cell, such as the comparative data shown in Table 1.

[0075] In one embodiment, the removal of the borosilicate glass layer in the battery cell to be reworked in the wet flower basket in step S302 includes: contacting the borosilicate glass layer on the surface of the over-facet in the battery cell to be reworked in the wet flower basket with an acidic solution, so that the acidic solution corrodes the borosilicate glass layer formed on the surface of the over-facet.

[0076] The acidic solution may be HF (hydrogen fluoride), HCL (hydrogen chloride), DI water (deionized water), or the like.

[0077] In this embodiment, since the solar cells to be reworked in the wet-process flower basket have their over-engraved surfaces facing the bottom of the wet-process flower basket, the borosilicate glass layer on the surface of the over-engraved surface is brought into contact with the acidic solution, which can ensure that the acidic solution effectively removes the borosilicate glass layer formed on the surface of the over-engraved surface, reduces light loss, and ensures the photoelectric conversion performance of the finished solar cell after over-engraving and rework.

[0078] In one embodiment, step S303 of performing a first corrosion and polishing treatment on the over-engraved surface of the cell to be reworked after the borosilicate glass layer is removed includes: contacting the over-engraved surface of the cell to be reworked after the borosilicate glass layer is removed with an alkaline solution, so that the alkaline solution performs a first corrosion and polishing on the over-engraved surface of the cell to be reworked.

[0079] In this embodiment, on the one hand, by contacting the over-engraved facet of the cell to be reworked after the borosilicate glass layer is removed with an alkaline solution, the over-engraved facet can be polished to ensure that the surface of the cell to be reworked has no color difference after being treated by the over-engraved rework treatment method of this application. On the other hand, by polishing with an alkaline solution, residual impurities and particulate matter on the surface of the cell to be reworked can be effectively removed, which helps to improve the quality and efficiency of subsequent process steps, such as reducing light capture loss and improving the overall performance of the cell. Alkaline polishing of the over-engraved facet of the cell to be reworked also helps to smooth the surface of the cell to be reworked, reduce minor unevenness, and help to improve the light absorption rate and the photoelectric conversion efficiency of the prepared solar cell product.

[0080] In one embodiment, the over-etching rework method further includes: re-texturing the other side of the to-be-reworked cell opposite to the over-etched side of the to-be-reworked cell before replacing the texturing solution.

[0081] In this embodiment, the cell to be reworked is retextured before the texturizing solution is replaced, which can prevent the cell to be reworked from contaminating the texturizing solution and causing unnecessary waste.

[0082] In one embodiment, a preset solar cell preparation process includes: contacting the back side of the cell with an alkaline solution so that the alkaline solution performs a second corrosion polishing treatment on the back side of the cell; the back side of the cell is a side without a borosilicate glass layer; wherein, when the cell is found to be a cell to be reworked after inspection, the front side of the cell is an over-engraved side of the reworked cell; the front side of the cell is opposite to the back side of the cell, and a borosilicate glass layer is provided on the front side of the cell.

[0083] The second etching and polishing process can be understood as an etching and polishing process in which over-etching occurs. The difference from the first etching and polishing process is that the first etching and polishing process is an etching and polishing process for removing the over-etching effect caused by the second etching and polishing process.

[0084] In this embodiment, when the cell that has undergone the second corrosion and polishing treatment is over-engraved, the cell is a cell to be reworked. At this time, the front side of the cell that has undergone the second corrosion and polishing treatment is an over-engraved surface, and since the preceding process of the second corrosion and polishing treatment is a boron diffusion process, the front side of the cell that has undergone the second corrosion and polishing treatment is provided with a borosilicate glass layer.

[0085] In one embodiment, a preset solar cell preparation process includes: contacting the front side of the cell with an alkaline solution so that the alkaline solution removes a damaged layer on the front side of the cell generated in a previous solar cell preparation process; the front side of the cell is a side without a tunneling oxide layer; wherein, when the cell is found to be a cell to be reworked after inspection, the back side of the cell is an over-engraved side of the reworked cell; the back side of the cell is opposite to the front side of the cell, and a tunneling oxide layer is provided on the back side of the cell.

[0086] The damaged layer mentioned above may refer to a film layer such as a phosphosilicate glass layer that is harmful to the performance of the solar cell.

[0087] In this embodiment, the previous step of contacting the front side of the cell with an alkaline solution so that the alkaline solution removes the damaged layer on the front side of the cell generated in the previous solar cell preparation process includes the steps of back-side deposition of the tunneling oxide layer and phosphorus diffusion. Therefore, the back side of the cell can be understood as the side provided with the tunneling oxide layer, and contacting the front side of the cell with an alkaline solution so that the alkaline solution removes the damaged layer on the front side of the cell generated in the previous solar cell preparation process can be understood as a positive etching process for removing the phosphosilicate glass layer on the front side of the cell.

[0088] In one embodiment, a method for reworking an overetching process is also provided. Figure 4 , attached Figure 4 FIG3 shows a flow chart of the over-etching rework method in an embodiment of the present application. Figure 4 The process of preparing a solar cell is described as follows: texturing, boron diffusion, BSG removal, alkaline polishing, LP (laser etching), phosphor diffusion, PSG removal, positive etching, ALD (atomic layer deposition), and screen printing. It is understood that in other embodiments, the process of preparing a solar cell may be other, not limited to this. The over-engraved rework method in this embodiment includes: using tweezers (or cotton gloves + PE gloves) to re-insert the cell to be reworked, which has been intercepted by the alkali polishing feed, into the wet process basket for texturing with the over-engraved facet of the cell to be reworked facing the bottom of the wet process basket; according to a fixed collection date as needed, the cell to be reworked is uniformly sent to the texturing feeder; after the texturing process, the other side of the cell to be reworked opposite the over-engraved facet can be texturized normally, and the texturized surface is not significantly different from that of a normal cell; the over-engraved facet is originally a BSG silicon oxide layer, which is removed in the subsequent BSG removal and alkali polishing processes, resulting in a normal appearance of the cell to be reworked after the alkali polishing process; when the re-textured cell is re-textured, the over-engraved facet of the cell to be reworked cannot be texturized normally, and compared to a normal cell, only one side is texturized normally, resulting in less weight loss. After the alkali polishing process, the subsequent process is synchronized with the normal cells on the solar cell production line.

[0089] Similarly, it is also applicable to the rework of over-engraving in the positive etching process. In the positive etching process, the over-engraved abnormal surface is on the back of the battery cell. The over-engraved surface of the battery cell to be reworked after the positive etching process is re-inserted into the wet flower basket for texturing with the over-engraved surface facing the bottom of the wet flower basket. They are collected and sent to texturing in a unified manner. The battery cell to be reworked after the positive etching process can also be normally texturized, and the surface color difference is removed through the BSG removal and alkali polishing process after re-texturing.

[0090] In this embodiment, it can be seen from the actual tracking data of Tables 1 to 4 above that there is no obvious difference in the appearance and velvet data of the reworked battery cells treated by the over-engraving rework method in this embodiment, and there is no difference in the appearance and SPC data of the battery cells after alkaline polishing. There is no difference in the screen tracking efficiency and EL compared with the same period, which can reduce the weight loss while ensuring the performance of the finished solar cell unchanged.

[0091] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0092] In one embodiment, the present application further provides a solar cell. The solar cell in this embodiment is prepared by the over-etching rework method in any of the above embodiments.

[0093] In one embodiment, the solar cell manufactured by the over-etching rework method in any of the above embodiments comprises a TOPCon cell (Tunneling Oxide Passivated Contact Solar Cell).

[0094] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above 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 application.

[0095] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for reworking an overetching process, characterized in that: The over-engraving rework method comprises: Testing the solar cells after the preset solar cell preparation process; Collect the over-engraved cells to be reworked according to the test results; The other side of the cell to be reworked opposite to the over-engraved facet of the cell to be reworked is re-textured; the over-engraved facet of the cell to be reworked is an etched face of the cell to be reworked where the actual etching depth is greater than the target etching depth.

2. The over-etching rework method according to claim 1, characterized in that: The re-texturing of the other side of the to-be-reworked battery sheet opposite to the over-engraved side of the to-be-reworked battery sheet comprises: Place the over-engraved surface of the cell to be reworked toward the bottom of the wet process basket; The other side of the cell to be reworked in the wet process basket, which is opposite to the over-engraved side, is re-textured.

3. The over-etching rework method according to claim 2, characterized in that: The over-engraving rework method further comprises: Performing boron diffusion on the cell to be reworked to form a borosilicate glass layer on the surface of the overcut facet; Removing the borosilicate glass layer in the cell to be reworked in the wet process basket; The overcut surface of the cell to be reworked is subjected to a first etching and polishing treatment after the borosilicate glass layer is removed.

4. The over-etching rework method according to claim 3, characterized in that: The method of removing the borosilicate glass layer in the cell to be reworked in the wet process basket comprises: The borosilicate glass layer on the surface of the overcut facet in the cell to be reworked in the wet process basket is brought into contact with an acidic solution, so that the acidic solution corrodes the borosilicate glass layer formed on the surface of the overcut facet.

5. The over-etching rework method according to claim 3, characterized in that: The first etching and polishing process is performed on the overcut surface of the cell to be reworked after the borosilicate glass layer is removed, comprising: The overcut surface of the cell to be reworked after the borosilicate glass layer is removed is brought into contact with an alkaline solution, so that the alkaline solution performs a first etching and polishing on the overcut surface of the cell to be reworked.

6. The over-etching rework method according to claim 1, characterized in that: The over-engraving rework method further comprises: Before replacing the texturing solution, the other side of the cell to be reworked opposite to the over-engraved side of the cell to be reworked is texturized again.

7. The over-etching rework method according to claim 1, characterized in that: The preset solar cell preparation process comprises: The back side of the cell is contacted with an alkaline solution, so that the alkaline solution performs a second corrosion polishing treatment on the back side of the cell; the back side of the cell is a side without a borosilicate glass layer; Among them, when the battery cell is the battery cell to be reworked after inspection, the front side of the battery cell is the over-engraved surface of the reworked battery cell; the front side of the battery cell is opposite to the back side of the battery cell, and the borosilicate glass layer is provided on the front side of the battery cell.

8. The over-etching rework method according to claim 1, characterized in that: The preset solar cell preparation process comprises: The front side of the cell is contacted with an alkaline solution, so that the alkaline solution removes the damage layer on the front side of the cell generated in the previous solar cell preparation process; the front side of the cell is the side without a tunneling oxide layer; Among them, when the battery cell is the battery cell to be reworked after inspection, the back side of the battery cell is the over-engraved surface of the reworked battery cell; the back side of the battery cell is opposite to the front side of the battery cell, and the tunneling oxide layer is provided on the back side of the battery cell.

9. A solar cell, characterized in that: The method is prepared by the over-etching reworking method as claimed in any one of claims 1 to 8.

10. The solar cell according to claim 9, characterized in that: The solar cell comprises a TOPCon cell.

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