A TOPCon battery with a transparent conductive layer and its preparation method

Abstract

The application provides a TOPCon cell with a transparent conductive layer and a preparation method thereof, and relates to the technical field of solar cells.The TOPCon cell comprises a semiconductor substrate, a tunneling layer is arranged on a first surface of the semiconductor substrate, a first conductive type semiconductor region is arranged on the tunneling layer, a first transparent conductive layer is arranged on the first conductive type semiconductor region, a first electrode is arranged on the first transparent conductive layer, a second conductive type semiconductor region is arranged on a second surface of the semiconductor substrate, a second passivation film is arranged on the second conductive type semiconductor region, a second transparent conductive layer is arranged on the second passivation film, and a second electrode is arranged on the second transparent conductive layer; and the first electrode and the second electrode are both made of non-silver paste conductive paste.In the application, the non-silver paste conductive paste is used to replace the traditional silver paste, the use of silver is reduced, and the manufacturing cost of the TOPCon cell is reduced.

Description

Technical Field

[0001] This invention relates to the field of solar cell technology, and in particular to a TOPCon cell with a transparent conductive layer and its preparation method. Background Technology

[0002] TOPCon solar cells offer significant advantages in efficiency, stability, degradation performance, bifaciality, environmental friendliness, cost, and reliability, making them a highly efficient, reliable, and environmentally friendly battery technology in the photovoltaic field. Currently, the metallization process is crucial in the fabrication of TOPCon solar cells, and the industry largely employs printed silver paste electrodes. These silver paste electrodes, serving as the positive and negative electrodes of the cell, are responsible for collecting the current generated by the photoelectric effect and transmitting it to the external circuitry.

[0003] With the increasing market share of TOPCon batteries in recent years, the demand for silver paste electrodes has also been increasing, leading to a tight supply of silver paste in the market and pushing up its price. The main component of silver paste is silver powder, and silver, as a precious metal, is relatively expensive, thus increasing the manufacturing cost of TOPCon batteries. Summary of the Invention

[0004] This invention provides a TOPCon battery with a transparent conductive layer and its preparation method, in order to solve the technical problem that most current TOPCon batteries use silver paste electrodes, resulting in high manufacturing costs.

[0005] To address the aforementioned technical problems, this invention discloses a TOPCon battery with a transparent conductive layer, comprising: a semiconductor substrate, a tunneling layer disposed on a first surface of the semiconductor substrate, a first conductive type semiconductor region disposed on the tunneling layer, a first transparent conductive layer disposed on the first conductive type semiconductor region, a first electrode disposed on the first transparent conductive layer, a second conductive type semiconductor region disposed on a second surface of the semiconductor substrate, a second passivation film disposed on the second conductive type semiconductor region, a second transparent conductive layer disposed on the second passivation film, and a second electrode disposed on the second transparent conductive layer, wherein both the first electrode and the second electrode are made of a non-silver paste conductive paste.

[0006] Preferably, non-silver conductive pastes include, but are not limited to, silver-coated copper paste, silver-coated nickel paste, silver-coated aluminum paste, and copper paste.

[0007] Preferably, the materials used to prepare the first transparent conductive layer and the second transparent conductive layer include any one or at least two combinations of indium tin oxide, indium zinc oxide, zinc aluminum oxide, fluorine-doped tin oxide, indium titanium oxide, indium tungsten oxide, and gallium-doped zinc oxide. Both the first transparent conductive layer and the second transparent conductive layer are prepared by at least one of magnetron sputtering, chemical vapor deposition, printing, and electron beam evaporation.

[0008] This invention discloses a method for fabricating a TOPCon battery with a transparent conductive layer. The method includes a tunneling layer formation operation on a first surface of a semiconductor substrate, a first conductivity type semiconductor region formation operation on the tunneling layer, a first transparent conductive layer formation operation on the first conductivity type semiconductor region, a first electrode formation operation on the first transparent conductive layer, a second conductivity type semiconductor region formation operation by incorporating a second conductivity type impurity into a second surface of the semiconductor substrate to form a second conductivity type semiconductor region, a second passivation film formation operation on the second conductivity type semiconductor region, a second transparent conductive layer formation operation on the second passivation film, and a second electrode formation operation on the second transparent conductive layer.

[0009] Preferably, the first electrode forming operation and the second electrode forming operation include laser sintering of the non-silver conductive paste using LECO technology.

[0010] Preferably, the laser sintering process uses laser-assisted sintering equipment.

[0011] Preferably, the first electrode forming operation includes one or more methods selected from printing, electroplating, sputtering, spraying, coating, rolling, and roll printing to prepare a non-silver paste conductive paste on a first transparent conductive layer on the first surface, and performing heat treatment on the non-silver paste conductive paste.

[0012] Preferably, the heat treatment temperature is 200-600℃.

[0013] Preferably, the second electrode formation operation includes using one or more methods selected from printing, electroplating, sputtering, spraying, coating, rolling, and roll printing to prepare a non-silver paste conductive paste on the second transparent conductive layer of the second surface, and performing heat treatment on the non-silver paste conductive paste.

[0014] Preferably, the heat treatment temperature is 200-600℃.

[0015] The technical solution of this invention has the following advantages: This invention provides a TOPCon battery with a transparent conductive layer and its fabrication method, relating to the field of solar cell technology. The TOPCon battery includes a semiconductor substrate, a tunneling layer disposed on a first surface of the semiconductor substrate, a first conductive type semiconductor region disposed on the tunneling layer, a first transparent conductive layer disposed on the first conductive type semiconductor region, a first electrode disposed on the first transparent conductive layer, a second conductive type semiconductor region disposed on a second surface of the semiconductor substrate, a second passivation film disposed on the second conductive type semiconductor region, a second transparent conductive layer disposed on the second passivation film, and a second electrode disposed on the second transparent conductive layer. Both the first electrode and the second electrode are made of non-silver paste conductive paste. In this invention, both the first electrode and the second electrode are made of non-silver paste conductive paste. By replacing traditional silver paste with non-silver paste conductive paste, the use of silver is reduced, thus lowering the manufacturing cost of the TOPCon battery.

[0016] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the means particularly pointed out in the written description and the accompanying drawings.

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0019] Figure 1 This is a schematic diagram of the overall structure of a TOPCon battery with a transparent conductive layer according to the present invention;

[0020] Figure 2 This is a schematic diagram of the screen printing equipment in this invention;

[0021] Figure 3 For the present invention Figure 2 Enlarged view of the structure at point A in the middle;

[0022] Figure 4 This is a schematic diagram of the internal structure of the drive box in this invention;

[0023] Figure 5 For the present invention Figure 4 Enlarged view of the structure at point B in the middle.

[0024] In the diagram: 1. Semiconductor substrate; 2. Tunneling layer; 3. Semiconductor region of the first conductivity type; 4. First transparent conductive layer; 5. First electrode; 6. Semiconductor region of the second conductivity type; 7. Second passivation film; 8. Second transparent conductive layer; 9. Second electrode; 10. Housing; 11. Placement port; 12. Support platform; 13. Screw; 14. Drive motor; 15. Slide table; 16. Moving seat; 17. Card plate; 18. Connecting plate; 19. Printing screen; 20. Electric push rod; 21. Slurry plate; 22. Scraper; 23. Slurry chamber; 24. Slurry storage tank; 25. Discharge pump; 26. Drive box; 27. Fixing plate; 28. Sliding plate; 29. ​​Drive plate; 30. Connecting spring; 31. Moving block; 32. Compression spring; 33. Sealing plate; 34. Reset spring; 35. Collection box; 36. Guide block; 37. Recovery pipe; 38. Pump body. Detailed Implementation

[0025] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0026] Furthermore, in this invention, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the invention. They are merely used to distinguish components or operations described using the same technical terms and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions and features of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0027] This invention provides a TOPCon battery with a transparent conductive layer, such as... Figure 1 As shown, it includes: a semiconductor substrate 1, a tunneling layer 2 disposed on a first surface of the semiconductor substrate 1, a first conductive type semiconductor region 3 disposed on the tunneling layer 2, a first transparent conductive layer 4 disposed on the first conductive type semiconductor region 3, a first electrode 5 disposed on the first transparent conductive layer 4, a second conductive type semiconductor region 6 disposed on a second surface of the semiconductor substrate 1, a second passivation film 7 disposed on the second conductive type semiconductor region 6, a second transparent conductive layer 8 disposed on the second passivation film 7, and a second electrode 9 disposed on the second transparent conductive layer 8. Both the first electrode 5 and the second electrode 9 are made of non-silver paste conductive paste.

[0028] Non-silver conductive pastes include, but are not limited to, silver-coated copper paste, silver-coated nickel paste, silver-coated aluminum paste, and copper paste;

[0029] The materials used to prepare the first transparent conductive layer 4 and the second transparent conductive layer 8 include any one or at least two combinations of indium tin oxide, indium zinc oxide, zinc aluminum oxide, fluorine-doped tin oxide, indium titanium oxide, indium tungsten oxide, and gallium-doped zinc oxide. Both the first transparent conductive layer 4 and the second transparent conductive layer 8 are prepared by at least one of magnetron sputtering, chemical vapor deposition, printing, and electron beam evaporation.

[0030] The working principle and beneficial effects of the above technical solution are as follows: In this invention, both the first electrode 5 and the second electrode 9 are made of non-silver paste conductive paste. Non-silver paste conductive paste includes, but is not limited to, silver-coated copper paste, silver-coated nickel paste, silver-coated aluminum paste, and copper paste. By replacing traditional silver paste with non-silver paste conductive paste, the use of silver is reduced.

[0031] Preferably, silver-coated copper paste can be used as the non-silver conductive paste. In 2024, the market price of high-priced silver paste was about RMB 8,230 / Kg. Silver-coated copper paste is about RMB 2,500-2,800 / Kg cheaper than silver paste. Taking a 182*183.75mm rectangular solar cell as an example, the mass of silver paste required for the first surface is about 40mg, and the mass of silver paste required for the second surface is about 40mg. Its power is about 8.4W, which means that the cost is saved by RMB 0.2-0.224 / W. It can be seen that using non-silver conductive paste can save the use of metallic silver, thereby reducing the manufacturing cost of TOPCon cells.

[0032] A first transparent conductive layer 4 is disposed on the first conductive type semiconductor region 3, and a second transparent conductive layer 8 is disposed on the second passivation film 7. The first transparent conductive layer 4 and the second transparent conductive layer 8 are prepared by at least one of magnetron sputtering, chemical vapor deposition, printing, and electron beam evaporation. The materials used to prepare the first transparent conductive layer 4 and the second transparent conductive layer 8 include any one or at least two combinations of indium tin oxide, indium zinc oxide, zinc aluminum oxide, fluorine-doped tin oxide, indium titanium oxide, indium tungsten oxide, and gallium-doped zinc oxide. After photogenerated carriers are generated inside the battery, they can be laterally conducted to the electrodes of the battery through the first transparent conductive layer 4 and the second transparent conductive layer 8 to form a current output. By setting the first transparent conductive layer 4 and the second transparent conductive layer 8, the first electrode 5 and the first conductive type semiconductor region 3 will not be in direct contact, and the second electrode 9 and the second conductive type semiconductor region 6 will not be in direct contact. This avoids the generation of interface states at the interface between the metal and the semiconductor, ensuring the effective transport of carriers and preventing the accumulation and recombination of carriers at the interface.

[0033] This invention also provides a method for fabricating a TOPCon battery with a transparent conductive layer, including a tunneling layer 2 forming operation on a first surface of a semiconductor substrate 1, a first conductive type semiconductor region 3 forming operation on the tunneling layer 2, a first transparent conductive layer 4 forming operation on the first conductive type semiconductor region 3, a first electrode 5 forming operation on the first transparent conductive layer 4, a second conductive type semiconductor region 6 forming operation by incorporating a second conductive type impurity into a second surface of the semiconductor substrate 1, a second passivation film 7 forming operation on the second conductive type semiconductor region 6, a second transparent conductive layer 8 forming operation on the second passivation film 7, and a second electrode 9 forming operation on the second transparent conductive layer 8.

[0034] The working principle and beneficial effects of the above technical solution are as follows: First, a semiconductor substrate 1 is prepared, which can be a silicon substrate; then, a tunneling layer 2, a first conductive type semiconductor region 3, a first conductive layer and a first electrode 5 are sequentially prepared on the first surface of the semiconductor substrate 1; on the second surface of the semiconductor substrate 1, a second conductive type semiconductor region 6, a second passivation film 7, a second transparent conductive layer 8 and a second electrode 9 are sequentially prepared. The first electrode 5 and the second electrode 9 are both prepared using non-silver paste conductive paste. Non-silver paste conductive paste includes, but is not limited to, silver-coated copper paste, silver-coated nickel paste, silver-coated aluminum paste, and copper paste. By replacing traditional silver paste with non-silver paste conductive paste, the use of silver is reduced, thereby reducing the manufacturing cost of TOPCon cells.

[0035] In one embodiment, the formation of the first electrode 5 and the formation of the second electrode 9 include laser sintering of the non-silver conductive paste using LECO technology.

[0036] Laser sintering is performed using laser-assisted sintering equipment.

[0037] The working principle and beneficial effects of the above technical solution are as follows: laser sintering of the first electrode 5 and the second electrode 9 by laser-assisted sintering equipment can improve battery efficiency and reduce production costs.

[0038] In one embodiment, the first electrode 5 formation operation includes one or more methods such as printing, electroplating, sputtering, spraying, coating, rolling, and roll printing to prepare a non-silver paste conductive paste on the first transparent conductive layer 4 on the first surface, and to perform heat treatment on the non-silver paste conductive paste at a temperature of 200-600°C.

[0039] In the second electrode 9 formation operation, one or more methods are used, including printing, electroplating, sputtering, spraying, coating, rolling, and roll printing, to prepare a non-silver paste conductive paste on the second transparent conductive layer 8 on the second surface, and to perform heat treatment on the non-silver paste conductive paste at a temperature of 200-600℃.

[0040] The working principle and beneficial effects of the above technical solution are as follows: The first electrode 5 can be prepared by using one or more methods such as printing, electroplating, sputtering, spraying, coating, rolling, and roll printing on the first transparent conductive layer 4 of the first surface using a non-silver paste conductive paste. The second electrode 9 can be prepared by using one or more methods such as printing, electroplating, sputtering, spraying, coating, rolling, and roll printing on the second transparent conductive layer 8 of the second surface using a non-silver paste conductive paste. The non-silver paste conductive paste is then sintered. The sintering temperature is set according to the material of the non-silver paste conductive paste. Preferably, the non-silver paste conductive paste is silver-coated copper paste, and the sintering temperature range is 200-600℃.

[0041] In one embodiment, such as Figure 2 As shown, the first electrode 5 and the second electrode 9 can be fabricated using screen printing equipment. The screen printing equipment includes a housing 10, with a placement opening 11 on one side of the housing 10. A support platform 12 is provided inside the housing 10, and a screw 13 is provided above the support platform 12. One end of the screw 13 is rotatably connected to the inner wall of the housing 10, and the other end of the screw 13 extends to the outside of the housing 10 and is connected to the output end of the drive motor 14. A slide 15 is provided on the screw 13, and the slide 15 is threadedly connected to the outer wall of the screw 13 through a connecting hole. The bottom of the slide 15 is slidably connected to the upper surface of the support platform 12. A movable seat 16 is provided on the slide 15, and a positioning hole is provided on the upper surface of the movable seat 16. The positioning hole is used to place the battery cell to be printed with non-silver conductive paste. A screen frame is set above the screw 13. The screen frame includes two symmetrically arranged clamping plates 17. The clamping plates 17 are connected to the upper surface of the support platform 12 through support columns. The left and right ends of the two clamping plates 17 are connected by connecting plates 18 respectively. Support bars are set on one side of the two clamping plates 17. The printing screen 19 is placed on the two support bars. The height of the upper surface of the connecting plate 18 does not exceed the height of the upper surface of the printing screen 19, and the height of the lower surface of the connecting plate 18 is not lower than the height of the lower surface of the printing screen 19. The height of the lower surface of the printing screen 19 is higher than the height of the upper surface of the battery cell to be printed with non-silver conductive paste. A paste coating mechanism is set inside the housing 10. The paste coating mechanism is used to coat the non-silver conductive paste on the printing screen 19.

[0042] The working principle and beneficial effects of the above technical solution are as follows: Taking the preparation of the first electrode 5 as an example, when preparing the first electrode 5, firstly, take the battery cell to be printed with non-silver conductive paste, and place the first transparent conductive layer 4 of the battery cell facing upward in the positioning hole of the moving seat 16 through the placement port 11. Then, start the drive motor 14. The drive motor 14 rotates and drives the screw 13 to rotate. The screw 13 rotates and drives the slide table 15 to slide on the support table 12. The slide table 15 drives the moving seat 16 to move towards the printing screen 19 until the battery cell moves directly below the printing screen 19 and the lower surface of the printing screen 19 is in contact with the upper surface of the battery cell. Then, the non-silver conductive paste is evenly applied to the printing screen 19 by the paste coating mechanism, thereby printing the first electrode 5. Then, the drive motor 14 reverses, causing the slide table 15 to move towards the placement port 11. When the movable seat 16 reaches the placement port 11, the battery cell can be removed from the positioning hole. The printing screen 19 is supported by two support strips on its front and rear sides, allowing it to be detachably installed between two clamping plates 17. The left and right ends of the printing screen 19 are limited by connecting plates 18 to prevent the printing screen 19 from shaking during the printing process, thus improving printing quality. The height of the lower surface of the printing screen 19 is higher than the height of the upper surface of the battery cell to be printed with non-silver conductive paste, creating a gap between the lower surface of the printing screen 19 and the upper surface of the battery cell to be printed with non-silver conductive paste, which facilitates the printing of the first electrode 5. The printing screen 19 is located between the two clamping plates 17, ensuring that the distance between the printing screen 19 and the battery cell remains constant, thereby improving the consistency of the printing of the first electrode 5 and achieving the requirement of resistance consistency.

[0043] In one embodiment, such as Figures 2-4As shown, the coating mechanism includes an electric push rod 20, which is located above the movable base 16. One end of the electric push rod 20 is connected to the inner wall of the housing 10. A coating plate 21 is provided at the output end of the electric push rod 20. The electric push rod 20 is used to push the coating plate 21 to move axially along the screw 13. The lower end of the coating plate 21 is located above the printing screen 19. A scraper 22 is provided on the side wall of the coating plate 21 near the placement port 11. The lower surface of the scraper 22 is on the same horizontal plane as the upper surface of the printing screen 19. The coating plate 21 is filled with paste. The material chamber 23 and the outer shell 10 are equipped with a slurry storage tank 24. A discharge pump 25 is installed on the shell 10. The input end of the discharge pump 25 is connected to the slurry storage tank 24, and the output end of the discharge pump 25 is connected to the upper end of the slurry chamber 23 through a telescopic hose. A drive box 26 is installed on the side of the slurry plate 21 away from the scraper 22. The lower end of the drive box 26 has an opening. A fixed plate 27 is installed inside the drive box 26. A sliding hole is provided in the fixed plate 27. A sliding plate 28 is installed in the sliding hole. The lower end of the sliding plate 28 extends below the fixed plate 27 and is equipped with a drive plate 28. 9. The drive plate 29 is slidably connected to the inner wall of the drive box 26. The upper end of the drive plate 29 is connected to the lower surface of the fixed plate 27 through several connecting springs 30. The lower end of the drive plate 29 extends to the outside of the drive box 26. The longitudinal section of the lower end of the drive plate 29 is semi-circular. A movable block 31 is provided above the fixed plate 27. The upper end of the movable block 31 is slidably connected to the upper inner wall of the drive box 26. The end of the movable block 31 away from the coating plate 21 is connected to the inner wall of the drive box 26 through a compression spring 32. The movable block 31 is in the shape of a right trapezoid. An inclined surface is provided on the side of the lower end near the slurry plate 21. The longitudinal section of the upper end of the sliding plate 28 is semi-circular. The upper end of the sliding plate 28 contacts the inclined surface of the moving block 31. A sealing hole is provided on the side of the moving block 31 near the slurry plate 21. A sealing plate 33 is slidably installed in the sealing hole. The sealing plate 33 is connected to the inner wall of the sealing hole through a return spring 34. The end of the sealing plate 33 away from the return spring 34 passes through the side wall of the drive box 26 and the side wall of the slurry plate 21 in sequence and extends into the slurry cavity 23. The sealing plate 33 is slidably connected to the through position.

[0044] The working principle and beneficial effects of the above technical solution are as follows: Initially, the drive plate 29 is located to the left of the card plate 17, and the drive plate 29 is not in contact with the card plate 17. At this time, the sealing plate 33 is located inside the slurry chamber 23, and the sealing plate 33 divides the internal space of the slurry chamber 23 into two parts. Then, according to the preset usage amount of non-silver conductive slurry for preparing the first electrode 5, the non-silver conductive slurry is injected into the slurry plate 21 through the discharge pump 25. The non-silver conductive slurry is stored on the sealing plate 33. A liquid level sensor is set in the slurry chamber 23. The liquid level sensor is used to monitor the real-time liquid level of the non-silver conductive slurry on the sealing plate 33. The liquid level sensor is electrically connected to the controller outside the housing 10, and the controller is electrically connected to the discharge pump 25. The real-time liquid level can be used to determine the level of the non-silver conductive slurry. When the injection volume of the non-silver conductive paste reaches the preset usage amount, the controller can control the discharge pump 25 to automatically stop working, thereby stopping the injection of paste. The non-silver conductive paste is then stored in the paste chamber 23 above the sealing plate 33. Due to the fluidity of the non-silver conductive paste, it is evenly spread on the sealing plate 33. When the battery cell moves directly below the printing screen 19, the electric push rod 20 is activated. The electric push rod 20 pushes the paste coating plate 21 towards the printing screen 19. The lower end of the drive plate 29 gradually contacts the clamping plate 17. Since the lower end of the drive plate 29 has a semi-circular cross-section, as the drive plate 29 slides along its end, it slides upward in the drive box 26, and the connecting spring 30 gradually compresses, driving... The moving plate 29 drives the sliding plate 28 to slide upwards. The upper end of the sliding plate 28 contacts the moving block 31 and drives the moving block 31 to slide away from the paste plate 21. The compression spring 32 is gradually compressed, and the moving block 31 drives the return spring 34 to stretch. When the lower end of the driving plate 29 slides to the upper surface of the clamping plate 17, the return spring 34 drives the sealing plate 33 to slide into the driving box 26, so that the non-silver conductive paste on the sealing plate 33 flows to the upper surface of the printing screen 19. The non-silver conductive paste can be evenly spread on the printing screen 19. As the non-silver conductive paste gradually decreases, the sealing plate 33 gradually slides into the driving box 26 under the action of the return spring 34, avoiding the residue of non-silver conductive paste on the sealing plate 33 and improving the non-silver conductive paste on the printing screen 19. To ensure material consistency, when the squeegee 22 passes the printing screen 19, it contacts the screen and evenly spreads the non-silver conductive paste, thus printing it onto the battery cell to form the first electrode 5. After printing, the moving seat 16 moves to the placement port 11, and then the electric push rod 20 retracts. Under the action of the connecting spring 30, the drive plate 29 returns to its original position. Under the action of the compression spring 32, the sealing plate 33 is reinserted into the paste chamber 23 and separates the paste chamber 23. The non-silver conductive paste is automatically injected into the paste chamber 23 according to the preset usage amount, which avoids waste of the non-silver conductive paste and further saves preparation costs. Moreover, the non-silver conductive paste is pre-stored in the paste chamber 23, which allows the non-silver conductive paste to be evenly spread on the sealing plate 33.After the sealing plate 33 is opened, the non-silver conductive paste can be evenly spread on the printing screen 19, ensuring that the non-silver conductive paste can flow down the upper surfaces of both ends of the printing screen 19, thereby improving the consistency and quality of the preparation of the first electrode 5.

[0045] In one embodiment, the upper surfaces of both ends of the card plate 17 are chamfered.

[0046] The working principle and beneficial effects of the above technical solution are as follows: by setting a chamfer, the wear of the lower end of the drive plate 29 can be reduced, making it easier for the drive plate 29 to contact and move with the card plate 17, thereby improving the service life of the drive plate 29 and the card plate 17.

[0047] In one embodiment, such as Figure 2 , Figure 3 As shown, a collection box 35 is provided at the end of the card plate 17 away from the placement port 11. A guide block 36 is provided inside the collection box 35. The longitudinal section of the guide block 36 is a right-angled triangle. The height of the end of the guide block 36 near the placement port 11 is higher than the height of the end of the guide block 36 away from the placement port 11. The side wall of the collection box 35 away from the placement port 11 is connected to one end of the recovery pipe 37. The other end of the recovery pipe 37 is connected to the input end of the pump body 38. The output end of the pump body 38 is connected to the inside of the slurry storage tank 24.

[0048] The working principle and beneficial effects of the above technical solution are as follows: the scraper 22 can scrape the excess non-silver conductive paste into the collection box 35. The non-silver conductive paste flows along the guide block 36 and is stored in the collection box 35. Then, the pump body 38 is started, which can draw the non-silver conductive paste in the collection box 35 into the paste storage box 24 through the recovery pipe 37, realizing the recycling of non-silver conductive paste, reducing the waste of non-silver conductive paste, and further saving the manufacturing cost of TOPCon battery.

[0049] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0050] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0051] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. Other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A method for manufacturing a TOPCon cell having a transparent conductive layer, characterized by, Comprising: a tunneling layer (2) forming operation of forming a tunneling layer (2) on a first surface of a semiconductor substrate (1), a first conductive type semiconductor region (3) forming operation of forming a first conductive type semiconductor region (3) on the tunneling layer (2), a first transparent conductive layer (4) forming operation of forming a first transparent conductive layer (4) on the first conductive type semiconductor region (3), a first electrode (5) forming operation of forming a first electrode (5) on the first transparent conductive layer (4), a second conductive type semiconductor region (6) forming operation of forming a second conductive type semiconductor region (6) by doping impurities of a second conductive type into a second surface of the semiconductor substrate (1), a second passivation film (7) forming operation of forming a second passivation film (7) on the second conductive type semiconductor region (6), a second transparent conductive layer (8) forming operation of forming a second transparent conductive layer (8) on the second passivation film (7), and a second electrode (9) forming operation of forming a second electrode (9) on the second transparent conductive layer (8); The first electrode (5) and the second electrode (9) are prepared by a screen printing device, and the screen printing device comprises a shell (10), a placing opening (11) is arranged on one side of the shell (10), a supporting table (12) is arranged in the shell (10), a screw rod (13) is arranged above the supporting table (12), one end of the screw rod (13) is rotatably connected with the inner wall of the shell (10), the other end of the screw rod (13) extends to the outside of the shell (10) and is connected with the output end of a driving motor (14), a sliding table (15) is arranged on the screw rod (13), the sliding table (15) is threadedly connected with the outer wall of the screw rod (13) through a connecting hole, the bottom of the sliding table (15) is slidably connected with the upper surface of the supporting table (12), a moving seat (16) is arranged on the sliding table (15), a positioning hole is formed in the upper surface of the moving seat (16), and a battery piece to be printed with non-silver paste conductive paste is placed in the positioning hole, a screen frame is arranged above the screw rod (13), the screen frame comprises two clamping plates (17) which are symmetrical front and back, the clamping plates (17) are connected with the upper surface of the supporting table (12) through supporting columns, the left and right ends of the two clamping plates (17) are connected through connecting plates (18), supporting strips are arranged on the sides of the two clamping plates (17) which are close to each other, a printing screen (19) is placed on the two supporting strips, the upper surface height of the connecting plates (18) is not higher than the upper surface height of the printing screen (19), the lower surface height of the connecting plates (18) is not lower than the lower surface height of the printing screen (19), and the height of the lower surface of the printing screen (19) is higher than the height of the upper surface of the battery piece to be printed with non-silver paste conductive paste, and a paste coating mechanism is arranged in the shell (10), and the paste coating mechanism is used for smearing non-silver paste conductive paste on the printing screen (19). The slurry coating mechanism comprises an electric push rod (20) located above the moving seat (16), one end of the electric push rod (20) is connected with the inner side wall of the shell (10), the output end of the electric push rod (20) is provided with a slurry coating plate (21), the electric push rod (20) is used for pushing the slurry coating plate (21) to move along the screw rod (13) in the axial direction, the lower end of the slurry coating plate (21) is located above the printing screen (19), the slurry coating plate (21) is provided with a scraper (22) close to the side wall of the placing opening (11), the lower surface of the scraper (22) is on the same horizontal plane as the upper surface of the printing screen (19), the slurry coating plate (21) is provided with a slurry cavity (23) inside, the shell (10) is provided with a slurry storage box (24) outside, the shell (10) is provided with a discharge pump (25) thereon, the input end of the discharge pump (25) is in communication with the slurry storage box (24), the output end of the discharge pump (25) is in communication with the upper end of the slurry cavity (23) through a flexible hose, the slurry coating plate (21) is provided with a drive box (26) away from the scraper (22), the lower end of the drive box (26) is provided with an opening, the drive box (26) is provided with a fixed plate (27) inside, the fixed plate (27) is provided with a sliding hole inside, the sliding hole is provided with a sliding plate (28) inside, the lower end of the sliding plate (28) extends to below the fixed plate (27) and is provided with a drive plate (29), the drive plate (29) is slidably connected with the inner wall of the drive box (26) in up-down direction, the upper end of the drive plate (29) is connected with the lower surface of the fixed plate (27) through a plurality of connecting springs (30), the lower end of the drive plate (29) extends to outside of the drive box (26), the lower end of the drive plate (29) is semicircular in longitudinal section, the drive box (26) is provided with a moving block (31) above, the upper end of the moving block (31) is slidably connected with the left-right inner wall of the upper end of the drive box (26), the end of the moving block (31) away from the slurry coating plate (21) is connected with the inner wall of the drive box (26) through a compression spring (32), the moving block (31) is a right-angled trapezoidal shape, the moving block (31) is provided with an inclined surface close to one side of the slurry coating plate (21), the upper end of the sliding plate (28) is semicircular in longitudinal section, the upper end of the sliding plate (28) is in contact with the inclined surface of the moving block (31), the moving block (31) is provided with a sealing hole close to the slurry coating plate (21), a sealing plate (33) is slidably arranged in the sealing hole, the sealing plate (33) is connected with the inner wall of the sealing hole through a reset spring (34), the end of the sealing plate (33) away from the reset spring (34) extends to the slurry cavity (23) by penetrating the side wall of the drive box (26), the side wall of the slurry coating plate (21) and the like in sequence, and the sealing plate (33) is sealingly and slidably connected with the penetration position. The TOPCon cell with a transparent conductive layer comprises a semiconductor substrate (1), a first surface of the semiconductor substrate (1) is provided with a tunneling layer (2), the tunneling layer (2) is provided with a first conductive type semiconductor region (3), the first conductive type semiconductor region (3) is provided with a first transparent conductive layer (4), the first transparent conductive layer (4) is provided with a first electrode (5), a second surface of the semiconductor substrate (1) is provided with a second conductive type semiconductor region (6), the second conductive type semiconductor region (6) is provided with a second passivation film (7), the second passivation film (7) is provided with a second transparent conductive layer (8), the second transparent conductive layer (8) is provided with a second electrode (9), and the first electrode (5) and the second electrode (9) are both made of non-silver paste conductive paste.

2. The method of claim 1, wherein the method further comprises: The non-silver paste conductive paste includes but is not limited to silver-coated copper paste, silver-coated nickel paste, silver-coated aluminum paste, and copper paste.

3. The method of claim 1, wherein the method further comprises: The preparation materials of the first transparent conductive layer (4) and the second transparent conductive layer (8) include any one or a combination of at least two of indium tin oxide, indium zinc oxide, zinc aluminum oxide, fluorine-doped tin oxide, indium titanium oxide, indium tungsten oxide, and gallium-doped zinc oxide, and the first transparent conductive layer (4) and the second transparent conductive layer (8) are both prepared by at least one of a magnetron sputtering method, a chemical vapor deposition method, a printing method, and an electron beam evaporation method.

4. The method of claim 1, wherein the method further comprises: The first electrode (5) forming operation and the second electrode (9) forming operation include laser sintering treatment of the non-silver paste conductive paste by LECO technology.

5. The method of claim 4, wherein the method further comprises: The laser sintering treatment uses a laser-assisted sintering device.

6. The method of claim 1, wherein the method further comprises: In the first electrode (5) forming operation, one or more of printing, electroplating, sputtering, spraying, coating, rolling, and rolling printing are used to prepare the non-silver paste conductive paste on the first transparent conductive layer (4) of the first surface, and heat treatment is performed on the non-silver paste conductive paste.

7. The method of claim 6, wherein the method further comprises: The heat treatment temperature is 200-600℃.

8. The method of claim 1, wherein the method further comprises: In the second electrode (9) forming operation, one or more of printing, electroplating, sputtering, spraying, coating, rolling, and rolling printing are used to prepare the non-silver paste conductive paste on the second transparent conductive layer (8) of the second surface, and heat treatment is performed on the non-silver paste conductive paste.

9. The method of claim 8, wherein the method further comprises: The heat treatment temperature is 200-600℃.

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