TOPCon battery film layer structure and preparation method thereof

Abstract

The invention provides a TOPCon cell film layer structure and a preparation method thereof, and relates to the technical field of solar cells, the TOPCon cell film layer structure comprises a substrate, a tunneling layer is arranged on a first surface of the substrate, a first conductive type semiconductor region is arranged on the tunneling layer, a transparent conductive layer is arranged on the first conductive type semiconductor region, and a second conductive layer is arranged on the transparent conductive layer. A plurality of first electrodes are arranged on the transparent conducting layer, a second conducting type semiconductor area is arranged on the second surface of the substrate, a second passive film A is arranged on the second conducting type semiconductor area, a second passive film B is arranged on the second passive film A, and a second electrode penetrates through the second passive film A and the second passive film B to be in contact with the second conducting type semiconductor area. According to the invention, the transparent conductive layer, the first electrode and the first conductive type semiconductor region form good interface contact, effective transmission of current carriers is promoted, recombination of the current carriers is reduced, transmission energy loss is reduced, and the photoelectric conversion efficiency of the cell is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a TOPCon cell film structure and a preparation method thereof. Background Art

[0002] In the TOPCon battery, the front electrode layer passes through the second passivation film A+B layer and contacts the second conductive type semiconductor layer, and the back electrode layer passes through the first passivation layer and contacts the first conductive type semiconductor layer, forming a conductive path between them.

[0003] In TOPCon cells, "recombination" is a key physical process. Recombination refers to the process in which photogenerated carriers (electrons and holes) return from the excited state to the ground state under the influence of various factors, that is, the electrons and holes recombine and disappear. This recombination can occur in different areas of the battery, such as bulk recombination (inside the semiconductor material), surface recombination (on the semiconductor surface) and metal recombination (in the metal-semiconductor contact area).

[0004] In the operation of solar cells, sunlight excites silicon semiconductors to generate electron-hole pairs, and these carriers need to be effectively separated and transmitted to the external circuit of the battery to generate current. However, if the carriers recombine during the transmission process, it will lead to energy loss, thereby reducing the photoelectric conversion efficiency of the battery. Summary of the invention

[0005] The present invention provides a TOPCon battery film structure and a preparation method thereof, which are used to solve the current technical problem that carriers recombine during transmission, resulting in energy loss and reducing the photoelectric conversion efficiency of the battery.

[0006] To solve the above technical problems, the present invention discloses a TOPCon battery film structure, including: a substrate, a tunneling layer is arranged on the first surface of the substrate, a first conductive type semiconductor region is arranged on the tunneling layer, a transparent conductive layer is arranged on the first conductive type semiconductor region, a plurality of first electrodes are arranged on the transparent conductive layer, a second conductive type semiconductor region is arranged on the second surface of the substrate, a second passivation film A is arranged on the second conductive type semiconductor region, a second passivation film B is arranged on the second passivation film A, and the second electrode passes through the second passivation film A and the second passivation film B and contacts with the second conductive type semiconductor region.

[0007] Preferably, the transparent conductive layer material includes but is not limited to one or more of indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), fluorine-doped tin oxide (FTO), indium titanium oxide (ITiO), indium tungsten oxide (IWO), and gallium-doped zinc oxide (GZO).

[0008] Preferably, the transparent conductive layer is prepared by at least one of magnetron sputtering, chemical vapor deposition, printing and electron beam evaporation.

[0009] A method for preparing a TOPCon battery film layer structure, comprising: a tunneling layer forming operation of forming a tunneling layer on a first surface of a substrate, a first conductive type semiconductor region forming operation of forming a first conductive type semiconductor region on the tunneling layer, a transparent conductive layer forming operation of forming a transparent conductive layer on the first conductive type semiconductor region, a first electrode forming operation of forming a first electrode on the transparent conductive layer, a second conductive type semiconductor region forming operation of forming a second conductive type semiconductor region by doping a second conductive type impurity into a second surface of a semiconductor substrate, a second passivation film A forming operation of forming a second passivation film A on the second conductive type semiconductor region, a second passivation film B forming operation of forming a second passivation film B on the second passivation film A, and a second electrode forming operation of forming a second electrode that passes through the second passivation film A and the second passivation film B and is connected to the second conductive type semiconductor region.

[0010] Preferably, one or more methods selected from the group consisting of printing, electroplating, sputtering, spraying, coating, rolling, and roll printing are used to prepare the first electrode using a slurry on the transparent conductive layer on the first surface, and then sintering the slurry. The slurry includes, but is not limited to, silver-coated copper slurry, silver-coated nickel slurry, silver-coated aluminum slurry, and copper slurry.

[0011] Preferably, the gate line layer of the first electrode is a single layer or multiple layers.

[0012] Preferably, the sintering temperature of the first electrode is 200-600°C.

[0013] Preferably, the second electrode is prepared on the second passivation film B on the second surface using silver paste by one or more methods selected from printing, electroplating, sputtering, spraying, coating, rolling, and roll printing, and then sintered.

[0014] Preferably, the gate line layer of the second electrode is a single layer or multiple layers.

[0015] Preferably, the sintering temperature of the second electrode is 600-850°C.

[0016] The technical solution of the present invention has the following advantages: the present invention provides a TOPCon battery film structure and a preparation method thereof, which relates to the technical field of solar cells. The TOPCon battery film structure includes a substrate, a tunneling layer is arranged on the first surface of the substrate, a first conductive type semiconductor region is arranged on the tunneling layer, a transparent conductive layer is arranged on the first conductive type semiconductor region, a plurality of first electrodes are arranged on the transparent conductive layer, a second conductive type semiconductor region is arranged on the second surface of the substrate, a second passivation film A is arranged on the second conductive type semiconductor region, a second passivation film B is arranged on the second passivation film A, and the second electrode passes through the second passivation film A and the second passivation film B to contact the second conductive type semiconductor region. In the present invention, the transparent conductive layer forms a good interface contact with the first electrode and the first conductive type semiconductor region, promotes the effective transmission of carriers, reduces the recombination of carriers, reduces the transmission energy loss, and improves the photoelectric conversion efficiency of the TOPCon battery.

[0017] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the devices particularly pointed out in the written description and the drawings of the description.

[0018] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 This is a schematic diagram of the overall structure of a TOPCon battery membrane structure of the present invention;

[0021] Figure 2 It is a schematic diagram of the structure of the drying furnace in the present invention;

[0022] Figure 3 For the present invention Figure 2 A magnified view of the structure in the middle.

[0023] In the figure: 1, substrate; 2, tunneling layer; 3, first conductive type semiconductor region; 4, transparent conductive layer; 5, first electrode; 6, second conductive type semiconductor region; 7, second passivation film A; 8, second passivation film B; 9, second electrode; 10, furnace body; 11, air inlet pipe; 12, partition; 13, diversion area; 14, drying area; 15, placement table; 16, guide plate; 17, support column; 18, connecting pipe; 19, sealing Shell; 20, horizontal plate; 21, electric push rod; 22, fixed plate; 23, first air outlet; 24, moving block; 25, rotating ball; 26, air outlet pipe; 27, fixed ring; 28, sealing plate; 29, sliding column; 30, limit block; 31, fixed block; 32, connecting rope; 33, weight block; 34, electric slide rail; 35, slide table; 36, guide rod; 37, motor; 38, screw; 39, moving table; 40, magnetic block. DETAILED DESCRIPTION

[0024] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0025] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present invention. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions and technical features between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0026] The embodiment of the present invention provides a TOPCon battery membrane structure, such as Figure 1 As shown, it includes: a substrate 1, a tunneling layer 2 is arranged on the first surface of the substrate 1, a first conductive type semiconductor region 3 is arranged on the tunneling layer 2, a transparent conductive layer 4 is arranged on the first conductive type semiconductor region 3, a plurality of first electrodes 5 are arranged on the transparent conductive layer 4, a second conductive type semiconductor region 6 is arranged on the second surface of the substrate 1, a second passivation film A7 is arranged on the second conductive type semiconductor region 6, a second passivation film B8 is arranged on the second passivation film A7, and a second electrode 9 passes through the second passivation film A7 and the second passivation film B8 and contacts the second conductive type semiconductor region 6;

[0027] The material of the transparent conductive layer 4 includes, but is not limited to, one or more of indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), fluorine-doped tin oxide (FTO), indium titanium oxide (ITiO), indium tungsten oxide (IWO), and gallium-doped zinc oxide (GZO);

[0028] The transparent conductive layer 4 is prepared by at least one of magnetron sputtering, chemical vapor deposition, printing and electron beam evaporation.

[0029] The working principle and beneficial effects of the above technical solution are as follows: the substrate 1 can be a silicon substrate 1, and a tunneling layer 2, a first conductive type semiconductor region 3, a transparent conductive layer 4 and a first electrode 5 are sequentially arranged on the first surface of the substrate 1. The preparation material of the transparent conductive layer 4 can be selected from materials with high conductivity and good light transmittance such as indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), fluorine-doped tin oxide (FTO), indium titanium oxide (ITiO), indium tungsten oxide (IWO), and gallium-doped zinc oxide (GZO). The transparent conductive layer 4 is prepared by any one of magnetron sputtering, chemical vapor deposition, printing, and electron beam evaporation. When photogenerated carriers are generated inside the battery, based on the high conductivity, the carriers can be transversely conducted to the electrodes of the battery through the transparent conductive layer 4 to form current output. The good light transmittance can ensure that the battery fully absorbs solar energy and improves the short-circuit current density of the battery.

[0030] The first electrode 5 can be made of silver-coated copper paste, which is cheaper than silver paste and can significantly reduce the production cost of the battery cell;

[0031] The second surface of the substrate 1 is sequentially provided with a second conductive type semiconductor region 6, a second passivation film A7, a second passivation film B8 and a second electrode 9 in the openings of the second passivation film A7 and the second passivation film B8. The second electrode 9 can be made of silver paste.

[0032] In the present invention, the transparent conductive layer 4 forms a good interface contact with the first electrode 5 and the first conductive type semiconductor region 3, promotes the effective transmission of carriers, avoids the accumulation and recombination of carriers at the interface, reduces the transmission energy loss, and improves the photoelectric conversion efficiency of the TOPCon battery. In addition, by setting the transparent conductive layer 4, the direct contact between the first electrode 5 and the first conductive type semiconductor region 3 is avoided, thereby avoiding the band bending caused by the work function difference, further promoting the effective transmission of carriers, reducing the recombination of carriers, and at the same time, it can avoid the first electrode 5 and the first conductive type semiconductor region 3 from contacting to produce interface states, preventing the interface states from capturing carriers and giving electrons and holes the opportunity to recombine at the interface.

[0033] The present application also provides a TOPCon battery film structure preparation method, including: a tunneling layer 2 forming operation of forming a tunneling layer 2 on the first surface of a 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 transparent conductive layer 4 forming operation of forming a 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 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 the second conductive type into the second surface of the semiconductor substrate, a second passivation film A7 forming operation of forming a second passivation film A7 on the second conductive type semiconductor region 6, a second passivation film B8 forming operation of forming a second passivation film B8 on the second passivation film A7, and a second electrode 9 forming operation of forming a second electrode 9 passing through the second passivation film A7 and the second passivation film B8 and connected to the second conductive type semiconductor region 6.

[0034] The working principle and beneficial effects of the above technical solution are as follows: first prepare a substrate 1, the substrate 1 can be a silicon substrate 1; then prepare a tunneling layer 2 on the first surface of the substrate 1; and prepare a first conductive type semiconductor region 3 on the tunneling layer 2; then prepare a second conductive type semiconductor region 6 on the second surface of the substrate 1; and prepare a second passivation film A7 and a second passivation film B8 on the second conductive type semiconductor region 6; then prepare a transparent conductive layer 4 on the first conductive type semiconductor region 3, the transparent conductive layer 4 is made of materials with high conductivity and good light transmittance such as indium tin oxide and aluminum-doped zinc oxide; prepare a first electrode 5 on the transparent conductive layer 4; prepare a second electrode 9 on the second passivation film B8; use the LECO process for auxiliary sintering to obtain a TOPCon cell; test and sort the TOPCon cell;

[0035] The transparent conductive layer 4 forms a good interface contact with the first electrode 5 and the first conductive type semiconductor region 3, promotes the effective transmission of carriers, avoids the accumulation and recombination of carriers at the interface, reduces the transmission energy loss, and improves the photoelectric conversion efficiency of the TOPCon cell;

[0036] The transparent conductive layer 4 can be made by magnetron sputtering or chemical vapor deposition. Specifically:

[0037] When the transparent conductive layer 4 is prepared by magnetron sputtering, high-energy ions (such as argon ions) are used to bombard the target material (such as indium tin oxide or aluminum-doped zinc oxide target) in a vacuum environment, so that the target atoms are sputtered and deposited on the substrate 1 to form a transparent conductive layer 4 thin film. By controlling the sputtering power, air pressure, temperature and other parameters, the thickness, structure and performance of the film can be adjusted. The thickness and composition of the film can be precisely controlled by the magnetron sputtering method, and a transparent conductive layer 4 with good uniformity and high quality can be prepared. It can be prepared at a lower temperature, which is suitable for deposition on a battery structure that is sensitive to temperature. It can achieve large-area film preparation and meet the needs of industrial production;

[0038] When the transparent conductive layer 4 is prepared by chemical vapor deposition, a gaseous precursor containing elements constituting the transparent conductive layer 4, such as indium, tin, zinc, etc., is introduced into the reaction chamber, and a transparent conductive layer 4 thin film is generated on the surface of the substrate 1 through a chemical reaction. For example, for the preparation of aluminum-doped zinc oxide thin film, diethyl zinc and trimethyl aluminum can be used as precursors, which react in an oxygen atmosphere and are deposited on the substrate 1. The chemical vapor deposition method can uniformly deposit thin films on substrates 1 of complex shapes, has strong adaptability to the substrate 1, and can accurately adjust the composition and structure of the thin film by controlling parameters such as the flow rate of the precursor, the reaction temperature and the pressure, which is conducive to the preparation of a high-quality transparent conductive layer 4.

[0039] On the basis of one embodiment, one or more methods selected from printing, electroplating, sputtering, spraying, coating, rolling, and roll printing are used to prepare the first electrode 5 on the transparent conductive layer 4 on the first surface using a slurry, and then sinter the slurry. The slurry includes but is not limited to silver-coated copper slurry, silver-coated nickel slurry, silver-coated aluminum slurry, and copper slurry.

[0040] The gate line layer of the first electrode 5 is a single layer or multiple layers;

[0041] The sintering temperature of the first electrode 5 is 200-600°C;

[0042] Using one or more methods selected from printing, electroplating, sputtering, spraying, coating, rolling, and roll printing, a second electrode 9 is prepared on the second passivation film B8 on the second surface using silver paste, and then sintered;

[0043] The gate line layer of the second electrode 9 is a single layer or multiple layers;

[0044] The sintering temperature of the second electrode 9 is 600-850°C.

[0045] The working principle and beneficial effects of the above technical solution are as follows: the first electrode 5 and the second electrode 9 are both made by one or more methods selected from printing, electroplating, sputtering, spraying, coating, rolling, and roll printing, wherein the first electrode 5 uses silver-coated copper paste, which is cheaper than silver paste and can significantly reduce the production cost of the battery cell, and the sintering temperature range of the first electrode 5 is 200-600°C, and the second electrode 9 uses silver paste, and the sintering temperature range of the second electrode 9 is 600-850°C.

[0046] Based on an embodiment, Figure 2 As shown, the first electrode 5 and the second electrode 9 can be prepared by a printing process, and sintering is performed after printing. In order to improve the preparation effect of the first electrode 5 or the second electrode 9, drying is performed before sintering, and the drying is performed in a drying furnace. The drying furnace includes a furnace body 10, and an air inlet pipe 11 is arranged at the upper end of the furnace body 10. The air inlet pipe 11 is used to pass drying gas. A partition 12 is arranged in the furnace body 10, a diversion area 13 is arranged above the partition 12, and a drying area 14 is arranged below the partition 12. A vent hole is arranged on the side wall of the furnace body 10, and the vent hole is connected to the drying area 14. A placement table 15 is arranged at the center of the inner wall of the bottom of the furnace body 10, and a guide plate 16 is arranged above the placement table 15. There is a gap between the left and right sides of the guide plate 16 and the inner wall of the furnace body 10. The lower surface of the guide plate 16 is connected to the bottom wall of the furnace body 10 through a support column 17. A through hole is arranged in the center of the guide plate 16, and a through hole is arranged at the through hole. A connecting pipe 18 is arranged, the upper end of the connecting pipe 18 is connected to the lower surface of the partition 12, a connecting area is arranged at the connecting position of the connecting pipe 18 and the partition 12, a plurality of mounting holes are arranged in the connecting area, the mounting holes pass through the upper and lower surfaces of the partition 12, a sealing shell 19 is arranged above the mounting holes, the upper end of the sealing shell 19 is connected to the transverse plate 20, electric push rods 21 are arranged at both ends of the transverse plate 20, the electric push rods 21 are connected to the inner wall of the furnace body 10 through a fixing plate 22, a plurality of first air outlet holes 23 are arranged in the partition 12, the first air outlet holes 23 pass through the upper and lower surfaces of the partition 12, and the plurality of first air outlet holes 23 are distributed on the outside of the connecting area, a moving block 24 is arranged in the first air outlet hole 23, the moving block 24 is truncated cone-shaped, one end of the moving block 24 is connected to the lower surface of the transverse plate 20, the diameter of the upper end of the moving block 24 is smaller than the diameter of the lower end of the moving block 24, and the diameter of the lower end of the moving block 24 is larger than the diameter of the first air outlet hole 23.

[0047] The working principle and beneficial effects of the above technical solution are as follows: organic solvents and other volatiles are usually added to the silver-coated copper paste or silver paste during the preparation process. In order to improve the preparation quality of the first electrode 5 and the second electrode 9 and ensure the smooth sintering process, the organic solvents or other volatiles in the paste need to be removed before sintering. Therefore, before the semi-finished battery cell printed with the paste enters the sintering furnace for sintering, it is necessary to use a drying furnace to dry the semi-finished battery cell. When drying, first put the semi-finished battery cell on the placement table 15 of the drying area 14 of the furnace body 10, and then start the electric push rod 21. The electric push rod 21 extends to drive the horizontal plate 20 to move downward, and the horizontal plate 2 0 drives the moving block 24 to move in the first air outlet 23, so that the diversion area 13 and the drying area 14 are connected through the first air outlet 23. At the same time, the horizontal plate 20 drives the sealing shell 19 to move downward and cover the outside of the mounting hole. The mounting hole cannot be connected with the inside of the diversion area 13. At this time, the drying gas is introduced into the diversion area 13 of the furnace body 10 through the air inlet pipe 11. The drying gas can flow into the drying area 14 through the first air outlet 23, and flow along the guide plate 16 toward the left and right side walls of the furnace body 10, and then flow downward along the side wall of the furnace body 10, and flow along the lower surface of the guide plate 16, so as to flow through the semi-finished battery cell, and the surface of the semi-finished battery cell is The printed slurry is dried, and the drying gas is finally discharged from the vent hole to realize the flow of drying gas. After the initial drying preset time, the printed slurry is initially dried and formed, and then the electric push rod 21 is gradually retracted, and the horizontal plate 20 drives the moving block 24 to move. The moving block 24 gradually blocks the first air outlet 23, and at the same time, the sealing shell 19 is separated from the surface of the partition 12. The drying gas can be directly blown to the surface of the semi-finished battery cell through the mounting hole, accelerating the drying speed of the slurry, avoiding the deformation of the slurry caused by direct blowing to the slurry during the initial drying, and improving the preparation quality of the first electrode 5 or the second electrode 9. By setting a drying furnace, the surface of the semi-finished battery cell is printed Drying the brushed slurry helps the solvent to evaporate in advance and reduce the formation of "gas channels" during the sintering process, thereby ensuring the continuity of the sintered layer, helping to improve the shear strength of the sintered joint, and making the connection after sintering more secure. At the same time, the early volatilization of the solvent helps the sintering molding and avoids excessive extrusion of the slurry during the sintering process, so that the sintered thickness remains uniform without obvious thinning. In addition, the drying process can remove residual moisture and solvent, so that the silver paste can reach the required temperature faster during the sintering process, speed up the sintering process, and reduce the amount of solvent that needs to be removed during the sintering process, thereby reducing energy consumption during the sintering process.

[0048] Based on an embodiment, Figure 2 , Figure 3As shown, a rotating ball 25 is arranged in the mounting hole, a second air outlet is arranged at the center of the rotating ball 25, an air outlet pipe 26 is arranged in the second air outlet, a fixing ring 27 is arranged in the air outlet pipe 26, a sealing plate 28 is arranged above the fixing ring 27, sliding holes are arranged on the left and right sides of the sealing plate 28, a sliding column 29 is arranged in the sliding hole, the lower end of the sliding column 29 is connected to the upper surface of the fixing ring 27, a limiting block 30 is arranged on the upper end of the sliding column 29, a fixing block 31 is arranged on the sealing plate 28, the fixing block 31 is made of magnetic material, a connecting rope 32 is arranged on the lower surface of the sealing plate 28, one end of the connecting rope 32 is connected to the center of the lower surface of the sealing plate 28, and the other end of the connecting rope 32 extends to the bottom of the fixing ring 27 and is provided with a weighting block 33, A driving mechanism is provided in the flow zone 13, and the driving mechanism includes two electric slide rails 34, and the two electric slide rails 34 are symmetrically arranged on the inner wall of the furnace body 10. A slide 35 is slidably arranged in the electric slide rails 34, and a guide rod 36 is provided between the two slides 35. A motor 37 is provided on the side wall of one of the slides 35, and a screw 38 is provided at the output end of the motor 37. The end of the screw 38 away from the motor 37 is rotatably connected to the side wall of the other slide 35. A moving platform 39 is provided on the screw 38, and the moving platform 39 is threadedly connected to the screw 38 through a threaded hole. A guide hole is provided in the moving platform 39, and the outer wall of the guide rod 36 is slidably connected to the inner wall of the guide hole. A magnetic block 40 is provided at the lower end of the moving platform 39, and the magnetic block 40 is located above the fixed block 31.

[0049] The working principle and beneficial effects of the above technical solution are as follows: after the sealing shell 19 is separated from the upper surface of the partition 12, the electric slide rail 34 and the motor 37 are started, and the electric slide rail 34 can control the sliding of the slide table 35, thereby adjusting the position of the motor 37, and the rotation of the motor 37 can drive the screw 38 to rotate, and the rotation of the screw 38 drives the movable table 39 to move along the guide rod 36, thereby driving the magnetic block 40 to move, and when the magnetic block 40 moves to the top of the fixed block 31, since the fixed block 31 is made of magnetic material, preferably, the fixed block 31 is made of iron block, under the action of magnetic force, the magnetic block 40 can drive the fixed block 31 to move in the direction close to the magnetic block 40 through magnetic force, and the fixed block 31 drives the sealing plate 28 to slide upward along the sliding column 29, so that the outlet pipe 26 is connected to the inside of the diversion area 13, and the drying gas can flow into the connecting pipe 18 through the outlet pipe 26 and blow to the battery cell semi-circle on the placement table 15. The surface of the finished product, the drying gas can dry the printed slurry, the moving platform 39 can drive the magnetic block 40 to move, and the movement of the magnetic block 40 drives the fixed block 31 to move, so that the rotating ball 25 rotates in the mounting hole, thereby adjusting the outlet angle of the outlet pipe 26, which is convenient for all-round drying of the surface of the semi-finished battery cell, further improving the drying effect, and ensuring the performance of the first electrode 5 and the second electrode 9. When the lower surface of the sealing shell 19 contacts the upper surface of the partition 12, the moving platform 39 moves to the side wall position of the furnace body 10. Under the action of gravity, the sealing plate 28 returns to its original position, and the sealing plate 28 contacts the fixing ring 27, further playing a sealing role, avoiding the drying gas from flowing out of the connecting pipe 18 during the initial drying process. The weighting block 33 can pull the sealing plate 28 through the connecting rope 32, so that the sealing plate 28 can contact the fixing ring 27 more smoothly, further improving the sealing effect.

[0050] In the description of the present invention, it is to 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”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0051] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A TOPCon battery membrane structure, characterized in that: include: A substrate (1) is provided, a tunneling layer (2) is provided on the first surface of the substrate (1), a first conductive type semiconductor region (3) is provided on the tunneling layer (2), a transparent conductive layer (4) is provided on the first conductive type semiconductor region (3), a plurality of first electrodes (5) are provided on the transparent conductive layer (4), a second conductive type semiconductor region (6) is provided on the second surface of the substrate (1), a second passivation film A (7) is provided on the second conductive type semiconductor region (6), a second passivation film B (8) is provided on the second passivation film A (7), and a second electrode (9) passes through the second passivation film A (7) and the second passivation film B (8) and contacts the second conductive type semiconductor region (6).

2. A TOPCon battery membrane structure according to claim 1, characterized in that: The material of the transparent conductive layer (4) includes, but is not limited to, one or more of indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), fluorine-doped tin oxide (FTO), indium titanium oxide (ITiO), indium tungsten oxide (IWO), and gallium-doped zinc oxide (GZO).

3. A TOPCon battery membrane structure according to claim 1, characterized in that: The transparent conductive layer (4) is prepared by at least one of magnetron sputtering, chemical vapor deposition, printing and electron beam evaporation.

4. A method for preparing a TOPCon battery membrane structure, used for preparing a TOPCon battery membrane structure as claimed in any one of claims 1 to 3, characterized in that: include: A tunneling layer (2) forming operation of forming a tunneling layer (2) on a first surface of a 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 transparent conductive layer (4) forming operation of forming a 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 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, a second passivation film A (7) forming operation of forming a second passivation film A (7) on the second conductive type semiconductor region (6), a second passivation film B (8) forming operation of forming a second passivation film B (8) on the second passivation film A (7), and a second electrode (9) forming operation of forming a second electrode (9) that passes through the second passivation film A (7) and the second passivation film B (8) and is connected to the second conductive type semiconductor region (6).

5. A method for preparing a TOPCon battery membrane structure according to claim 4, characterized in that: The first electrode (5) is prepared on the transparent conductive layer (4) on the first surface using a slurry by one or more methods selected from printing, electroplating, sputtering, spraying, coating, rolling, and roll printing, and then sintered. The slurry includes but is not limited to silver-coated copper slurry, silver-coated nickel slurry, silver-coated aluminum slurry, and copper slurry.

6. A method for preparing a TOPCon battery membrane structure according to claim 5, characterized in that: The gate line layer of the first electrode (5) is a single layer or multiple layers.

7. A method for preparing a TOPCon battery membrane structure according to claim 5, characterized in that: The sintering temperature of the first electrode (5) is 200-600°C.

8. The method for preparing a TOPCon battery membrane structure according to claim 4, characterized in that: The second electrode (9) is prepared on the second passivation film B (8) on the second surface using silver paste by one or more methods selected from printing, electroplating, sputtering, spraying, coating, rolling, and roll printing, and then sintered.

9. A method for preparing a TOPCon battery membrane structure according to claim 8, characterized in that: The grid line layer of the second electrode (9) is a single layer or multiple layers.

10. A method for preparing a TOPCon battery membrane structure according to claim 8, characterized in that: The sintering temperature of the second electrode (9) is 600-850°C.

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