Preparation method of selective emitter solar cell

Abstract

The invention provides a preparation method of a selective emitter solar cell, and the method comprises the steps: printing a dopant slurry layer on the front surface of a silicon wafer, and depositing an organic layer on the dopant slurry layer; cutting the organic layer by using first laser to enable the organic layer to have an opening, and exposing a corresponding area of the dopant slurry layer; carrying out melting treatment on the corresponding region of the dopant slurry layer exposed at the opening by using second laser, so that the region, corresponding to the opening, on the silicon wafer is heavily doped; third laser is used for removing the corresponding area, exposed at the opening, of the dopant slurry layer, the area, corresponding to the passivation contact structure, of the front face is exposed, and the first laser, the second laser and the third laser adopt the same laser system; and forming the front passivation contact structure in the exposed area. Through precise laser processing, the doping uniformity is improved, the silicon wafer damage is reduced, and the cell performance is optimized, so that the efficiency and the stability of the solar cell are remarkably improved.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to a method for preparing a selective emitter solar cell, a solar cell sheet and a component. Background Art

[0002] In existing solar cell manufacturing technology, selective emitter technology is widely used to improve the photoelectric conversion efficiency of the cell. However, when forming a doping layer on the surface of a silicon wafer using traditional doping methods, it is often difficult to achieve precise control, resulting in uneven distribution of dopants on the surface of the silicon wafer, which in turn affects the formation quality of the selective emitter and the performance of the cell. In addition, the existing process requires multi-step laser processing, and different steps often require different laser equipment or multiple adjustments to the laser position to complete the organic layer cutting, dopant melting and removal operations. This not only increases the complexity of the process and prolongs production time, but may also reduce overall production efficiency.

[0003] At the same time, the high-energy laser during laser processing can easily damage the surface of silicon wafers, causing microcracks or other defects, thus affecting the stability and service life of solar cells. Existing technologies are deficient in simplifying the laser processing process, reducing surface damage to silicon wafers, and achieving precise doping. Therefore, there is an urgent need for an improved process that can improve production efficiency while ensuring the accuracy of the doping process and effectively reducing damage to silicon wafers during laser processing. Summary of the invention

[0004] The purpose of the present application is to provide a method for preparing a selective emitter solar cell to solve the technical problems in the prior art such as insufficient precise control during the formation of the doping layer, cumbersome laser processing steps and damage to the surface of the silicon wafer, thereby affecting the photoelectric conversion efficiency, production efficiency, stability and service life of the solar cell.

[0005] In a first aspect, the present application provides a method for preparing a selective emitter solar cell, the method comprising:

[0006] printing a dopant paste layer on the front side of the silicon wafer and depositing an organic layer on the dopant paste layer;

[0007] Using a first laser to cut the organic layer, so that the organic layer has an opening, exposing a corresponding area of ​​the dopant paste layer;

[0008] Using a second laser to melt the area of ​​the dopant slurry layer corresponding to the exposed opening, so that the area corresponding to the opening on the silicon wafer is heavily doped;

[0009] Using a third laser to remove the area corresponding to the dopant paste layer exposed at the opening, exposing an area corresponding to the passivation contact structure on the front side, wherein the first laser, the second laser and the third laser are formed by the same laser system;

[0010] The front side passivation contact structure is formed in the exposed area.

[0011] Optionally, it also includes:

[0012] The dopant paste layer is printed multiple times on the front side of the silicon wafer, and the dopant content used in each printing is gradually reduced.

[0013] Optionally, the thickness of the dopant paste layer is gradually increased each time it is printed.

[0014] Optionally, the dopant slurry layer is printed on the entire surface.

[0015] Optionally, the dopant slurry layer is partially printed, and the width of the dopant slurry layer is gradually increased each time it is printed.

[0016] Optionally, it also includes:

[0017] Performing texturing on the front side of the silicon wafer;

[0018] After the front surface is texturized, the area corresponding to the front surface passivation contact structure is polished.

[0019] Optionally, the laser wavelength and power of the first laser, the second laser and the third laser are adjustable.

[0020] Optionally, the first laser, the second laser and the third laser spray inert gas or protective gas during the cutting process.

[0021] In a second aspect, the present application provides a solar energy component, comprising:

[0022] A battery array comprising a plurality of solar cells prepared according to the method for preparing a selective emitter solar cell according to any one of claims 1 to 8, and connected by a transparent conductive material;

[0023] A transparent adhesive film, used to cover the surface of the battery array;

[0024] The substrate is used to cover the two sides of the transparent adhesive film opposite to the battery array.

[0025] According to the technical solution of the present application, by accurately printing a dopant slurry layer on the surface of the silicon wafer, depositing an organic layer on this basis, and then using the same laser system to sequentially complete the steps of cutting, melting, and removal, the unevenness of the doping layer formation process in the traditional process and the damage to the silicon wafer caused by laser cutting are effectively reduced. This integrated laser processing method simplifies the process flow, reduces production costs, and improves the stability and service life of the final product, overcoming the inefficiency problem caused by multi-step operations in the prior art.

[0026] Furthermore, the present application ensures the uniform distribution of dopants on the surface of the silicon wafer by gradually reducing the dopant content and increasing the thickness of the printed layer, further optimizing the quality of the selective emitter. At the same time, by texturing and polishing the surface of the silicon wafer, the light absorption capacity and the overall performance of the battery are improved. In addition, the present application adopts a technical solution of laser cutting with adjustable wavelength and power, and spraying inert gas or protective gas to further reduce surface damage during processing and ensure the quality of the solar cell.

[0027] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic flow chart showing a method for preparing a selective emitter solar cell according to an embodiment of the present application is shown;

[0029] Figure 2 A schematic diagram showing the structure of a silicon wafer 101 after performing step S100 according to an embodiment of the present application is shown;

[0030] Figure 3 A schematic diagram showing the structure of the silicon wafer 101 after performing step S200 according to an embodiment of the present application is shown;

[0031] Figure 4 A schematic diagram showing the structure of the silicon wafer 101 after performing step S400 according to an embodiment of the present application is shown;

[0032] Figure 5 A schematic diagram showing the structure of the silicon wafer 101 after performing step S500 according to an embodiment of the present application is shown;

[0033] Figure 6 A schematic diagram showing a structure after a dopant paste layer 102 is printed multiple times on the front side of a silicon wafer 101 according to an embodiment of the present application;

[0034] Figure 7A schematic diagram of the structure after partial printing of a dopant paste layer 102 according to an embodiment of the present application is shown;

[0035] Figure 8 A schematic structural diagram of a solar photovoltaic assembly according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It is to be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some structures related to the present application are shown in the accompanying drawings, rather than all structures. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0037] The terms "including" and "having" and any variations thereof in this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0038] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0039] Figure 1 FIG. 1 is a schematic flow chart of a method for preparing a selective emitter solar cell according to an embodiment of the present application. Figure 1 As shown, the method comprises the following steps:

[0040] Step S100 , printing a dopant paste layer 102 on the front side of the silicon wafer 101 , and depositing an organic layer 103 on the dopant paste layer 102 .

[0041] Figure 2 FIG. 1 shows a schematic diagram of the structure of a silicon wafer 101 after performing step S100 according to an embodiment of the present application. Figure 2As shown, a dopant slurry layer 102 is printed on the front side of the silicon wafer 101, and an organic layer 103 is deposited on the dopant slurry layer 102. The coating of the dopant slurry layer 102 is to uniformly coat the material containing a high concentration of dopants (such as phosphorus, boron, etc.) on the surface of the silicon wafer 101 in the form of slurry. The deposition of the organic layer 103 (such as a polymer film) not only protects the dopant slurry, but also provides a shielding layer for the dopant layer in subsequent laser processing. During laser cutting and processing, the organic layer 103 can ensure that the dopant is exposed only in the specified area, thereby avoiding unnecessary diffusion or damage in other areas. In addition, the organic layer 103 can also reduce the impact of environmental factors (such as oxygen or moisture in the air) on the dopant and improve the quality of subsequent doping. Through the protection of the organic layer 103 and the uniform coating of the slurry, the laser processing and doping diffusion in the subsequent steps will be more controllable. This control is particularly important in large-scale production because it can ensure that the processing accuracy of each silicon wafer 101 is consistent, thereby improving the yield and the quality stability of the device.

[0042] In step S200 , the organic layer 103 is cut using a first laser, so that the organic layer 103 has an opening 1031 to expose a corresponding region of the dopant paste layer 102 .

[0043] Figure 3 FIG. 1 shows a schematic diagram of the structure of a silicon wafer 101 after performing step S200 according to an embodiment of the present application. Figure 3 As shown, the organic layer 103 is cut using a first laser so that the organic layer 103 has an opening 1031, exposing the corresponding area of ​​the dopant slurry layer 102. Laser cutting technology uses a high-energy laser beam to accurately remove the organic layer 103 to form an opening 1031. The wavelength, energy and focus of the first laser are precisely adjusted to ensure that only the organic layer 103 is removed without any impact on the underlying dopant slurry layer 102 or the silicon wafer 101 itself. Laser cutting is a non-contact processing method that can complete the removal of the organic layer 103 in a very short time and does not apply mechanical stress to the silicon wafer 101. Compared with traditional mechanical cutting, laser cutting has higher precision and flexibility, and is particularly suitable for manufacturing complex graphics with high resolution. In addition, the laser cutting process has low requirements for the processing environment and can be carried out in a conventional atmospheric environment, further simplifying the process flow.

[0044] In step S300 , a second laser is used to melt the area of ​​the dopant slurry layer 102 corresponding to the opening 1031 , so that the area on the silicon wafer 101 corresponding to the opening 1031 is heavily doped.

[0045] In this step, a second laser is used to locally heat the exposed area of ​​the dopant paste layer 102, so that the dopant melts and diffuses into the silicon wafer 101. Laser heating can provide very localized and precise energy input, ensuring that the dopant diffuses into the silicon wafer 101 only in the opening 1031 area. This local heating method can adjust the diffusion depth and concentration of the dopant by controlling the energy density, exposure time and scanning speed of the laser.

[0046] By laser melting doping, heavy doping treatment can be achieved in a local area to form a high conductivity area with low resistance. Compared with the traditional diffusion furnace method, the laser melting method has the advantages of fast speed, low energy consumption and high processing accuracy. In addition, this local heating method can avoid high temperature treatment of the entire silicon wafer 101, reducing the risk of thermal damage to the silicon wafer 101.

[0047] Step S400 , using a third laser to remove the area corresponding to the dopant paste layer 102 exposed at the opening 1031 , exposing the area corresponding to the passivation contact structure on the front side, and the first laser, the second laser and the third laser use the same laser system.

[0048] Figure 4 FIG. 1 shows a schematic diagram of the structure of a silicon wafer 101 after performing step S400 according to an embodiment of the present application. Figure 4 As shown, a third laser is used to remove the area corresponding to the dopant slurry layer 102 exposed at the opening 1031, exposing the area corresponding to the passivation contact structure on the front side. Through the third laser irradiation, the heavily doped area is further processed to remove the residual dopant slurry, ensuring that the passivation contact structure can be directly constructed on the silicon wafer 101. This step S400 cleans the area that has been doped and exposes the surface of the silicon wafer 101 to facilitate the subsequent construction of the passivation contact structure. Since laser processing has the advantages of high selectivity and non-contact, this step can ensure that the exposed area is very clean, thereby providing good surface conditions for the next step of passivation structure formation.

[0049] When performing different tasks, different requirements are placed on laser parameters such as energy, wavelength, and focus to achieve the effect of removal or cladding. The first laser, the second laser, and the third laser use the same laser system, which simplifies the equipment configuration, reduces the need for multiple sets of laser equipment, and reduces equipment procurement and maintenance costs. In the actual production process, when using different lasers, it is only necessary to adjust the parameters on the laser system, without the need to replace the laser equipment and material position, reducing the error caused by replacing the laser equipment or material position. At the same time, this integrated design improves the continuity and automation level of the process flow, without the need to switch equipment between different processes, greatly shortening the production cycle.

[0050] In addition, using the same system can ensure the consistency of parameters in each step of laser processing, thereby improving the precision and quality of product processing. This integrated processing method helps reduce repeated heating of the silicon wafer 101, avoids the accumulation of excessive thermal stress, ensures the structural integrity of the silicon wafer 101, and further improves the overall production efficiency and final product performance.

[0051] Step S500 , forming a front passivation contact structure in the exposed area.

[0052] Figure 5 FIG. 1 shows a schematic diagram of the structure of a silicon wafer 101 after performing step S500 according to an embodiment of the present application. Figure 5 As shown, the surface area of ​​the silicon wafer 101 exposed after the dopant layer is removed by laser in the above step forms a passivation contact structure, which includes a doping layer 104 , a dielectric layer 105 and a transition layer 106 .

[0053] The passivation contact structure reduces surface recombination by covering the surface with an insulating layer or a low-doping layer 104, thereby improving the electron transmission performance of the silicon wafer 101. The passivation contact structure can effectively reduce the surface recombination effect, which will significantly affect the electron transmission efficiency. By forming a passivation structure in the heavily doped area, it is possible to achieve high conductivity contact while maintaining low recombination loss, thereby optimizing device performance, significantly improving photoelectric conversion efficiency, and reducing energy loss.

[0054] According to the above embodiment, by accurately printing the dopant slurry layer 102 on the surface of the silicon wafer 101, and depositing the organic layer 103 on this basis, and then using the same laser system to sequentially complete the steps of cutting, melting and removal, the uniformity of the doping layer 104 is greatly improved, and the damage to the silicon wafer 101 caused by laser cutting is effectively reduced. At the same time, the design of using the same laser system not only simplifies the process flow, reduces equipment switching and maintenance costs, but also ensures the processing accuracy and consistency of each step, thereby improving production efficiency. This integrated laser processing method further enhances the stability of the final product, extends its service life, and reduces the overall production cost, and has higher industrial application value.

[0055] In some embodiments, the dopant paste layer 102 is printed multiple times on the front side of the silicon wafer 101 , and the dopant content used in each printing is gradually reduced.

[0056] Figure 6 FIG. 1 is a schematic diagram showing a structure after a dopant paste layer 102 is printed multiple times on the front side of a silicon wafer 101 according to an embodiment of the present application. Figure 6As shown, the dopant paste layer 102 is printed three times on the front side of the silicon wafer 101, namely, the first dopant paste layer 1021, the second dopant paste layer 1022 and the third dopant paste layer 1023. It should be noted that, Figure 6 The three-layer structure of the dopant paste layer 102 shown is only one embodiment of the present application. In other cases, it can be printed multiple times as needed to form a multi-layer structure, which will not be described in detail here.

[0057] The dopant slurry layer 102 is printed multiple times on the front side of the silicon wafer 101, and the dopant content used in each printing is gradually reduced to ensure a smoother transition between the heavily doped area and the lightly doped area. This multiple printing method can accurately control the doping depth and concentration distribution, avoid the non-uniformity of the doping layer 104 caused by a one-time high-concentration doping, and reduce the surface damage of the silicon wafer 101. Gradually reducing the doping concentration can avoid excessive damage to the surface of the silicon wafer 101 caused by high-concentration doping, and reduce the mechanical stress and crack risk of the silicon wafer 101.

[0058] In some embodiments, during the multiple printings, the thickness of the dopant paste layer 102 is gradually increased each time.

[0059] refer to Figure 6 , the thickness of the first dopant slurry layer 1021 is less than that of the second dopant slurry layer 1022, and the thickness of the second dopant slurry layer 1022 is less than that of the third dopant slurry layer 1023. By gradually increasing the thickness each time the dopant slurry layer 102 is printed, the doping distribution can be effectively optimized and the overall processing accuracy can be improved. The thicker slurry layer provides more dopant materials during the laser melting process, making the heavily doped area more stable and uniform, ensuring high conductivity on the surface of the device. This thickness control can also effectively adjust the doping depth, form a more accurate doping layer 104, avoid excessive diffusion, and optimize the electrical properties of the semiconductor device. In addition, the gradually increasing thickness plays a protective role during laser processing, reduces the direct impact of the laser on the surface of the silicon wafer 101, reduces the mechanical stress and physical damage that may occur during the processing, thereby maintaining the structural integrity of the silicon wafer 101. This design not only helps to improve the processing accuracy of the silicon wafer 101, but also reduces hidden dangers such as microcracks, ensuring the safety of the silicon wafer 101 during the production process. This thickness-increasing process method can improve the overall performance and stability of the product, extend the service life of the device, and further improve manufacturing efficiency and the controllability of product quality control.

[0060] In some embodiments, the dopant paste layer 102 is printed on the entire surface.

[0061] refer to Figures 1 to 6, when printing the dopant slurry layer 102 on the silicon wafer 101, it is printed on the entire surface. Printing the dopant slurry layer 102 on the entire surface can ensure that the dopant is evenly distributed on the surface of the silicon wafer 101, improving the uniformity of doping and the electrical properties of the silicon wafer 101. At the same time, this method simplifies the process flow, reduces the complexity and error of local processing, and significantly improves the processing speed and accuracy. Whole-surface printing also optimizes the surface quality, avoids stress and defects caused by local unevenness, and contributes to the large-scale and efficient production of high-quality semiconductor devices.

[0062] In some other embodiments, the dopant paste layer 102 is printed locally, and the width of the dopant paste layer 102 is gradually increased each time it is printed.

[0063] Figure 7 FIG. 1 shows a schematic diagram of a structure after a dopant paste layer 102 is partially printed according to an embodiment of the present application. Figure 7 As shown, a local printing method is adopted when printing the dopant slurry layer 102 on the silicon wafer 101, and three local printings are performed, and the width of the dopant slurry layer 102 printed each time increases successively, so as to obtain the fourth dopant slurry layer 1024, the fifth dopant slurry layer 1025 and the sixth dopant slurry layer 1026. Local printing can accurately control the dopant to be applied only to specific areas, avoid unnecessary doping, and thus optimize the function of the semiconductor device. This method enables specific doping characteristics to be achieved in key parts, and improves the performance and efficiency of the device. By gradually increasing the printing width, the gradual expansion of the dopant can be achieved on the silicon wafer 101, forming a gradually doped area from narrow to wide. This design helps to establish a smoother doping transition layer 106, improve the doping concentration distribution, and improve the efficiency of electron transmission. At the same time, local printing can effectively avoid material waste, and the dopant is only applied to the required area. Combined with the strategy of gradually increasing the width, the amount of dopant used is further optimized, so that while meeting the design requirements, unnecessary material consumption is reduced, and production costs are reduced. In addition, the design of gradually increasing the printing width can effectively disperse the heat and physical stress in laser processing, avoid damage to local areas due to excessive heating, maintain the structural integrity of the silicon wafer 101, and reduce cracks and stress concentration problems.

[0064] In some embodiments, the method for preparing a selective emitter solar cell further comprises the following steps:

[0065] Step S600 , texturing the front side of the silicon wafer 101 .

[0066] In step S600, the front side of the silicon wafer 101 is textured by chemical etching, sandblasting or other mechanical methods. This process forms a tiny concave-convex structure on the surface of the silicon wafer 101, usually a nanometer-level or micrometer-level texture, which can effectively change the incident mode of light.

[0067] The textured surface can effectively increase the incident angle and scattering of light, reduce reflection loss, thereby increasing light absorption and improving the efficiency of solar cells. By changing the microstructure of the surface, the texture treatment can significantly reduce the reflectivity of light on the surface, allowing more light to be absorbed and converted into electrical energy. At the same time, the texture treatment increases the incident time of light on the cell surface, resulting in more carriers being generated, increasing the current output under lighting conditions, and thus improving the overall performance of solar cells.

[0068] Step S700, after the front surface is textured, the area corresponding to the front surface passivation contact structure is polished.

[0069] After the front side is textured, the area corresponding to the front passivation contact structure is selectively polished. Through the polishing process, the surface of the passivation contact structure can become smoother, which can reduce the contact resistance and ensure good electrical contact performance. The polishing process can effectively remove tiny defects, impurities and oxide layers on the surface of the silicon wafer 101, reduce the carrier recombination rate, and thus improve the overall performance of the battery. A clean interface helps the effective transmission of carriers, ensuring that the battery performs more efficiently when working.

[0070] In some embodiments, the laser wavelengths and powers of the first laser, the second laser, and the third laser used in the above steps are all adjustable.

[0071] Different laser wavelengths have different absorption characteristics for different materials. The adjustable wavelength enables the laser to be optimized for different materials such as the silicon wafer 101, the dopant slurry layer 102, and the passivation contact structure to achieve the best processing effect. This flexibility can ensure high efficiency and accuracy during laser processing. By adjusting the laser power, the penetration depth of the laser in the material and the processing effect can be precisely controlled. For example, higher power can be used for deep melting processing, while lower power is suitable for surface cutting or light processing. This precise control can reduce damage to the silicon wafer 101 and other materials and improve the quality of the finished product.

[0072] In addition, adjustable laser power makes heat management during processing more effective. By adjusting the power, overheating and expansion of the heat-affected zone can be prevented, and material deformation or structural damage caused by heat accumulation can be reduced. This helps to maintain the overall structural integrity of the silicon wafer 101 and improve processing accuracy and reliability. In practical applications, depending on the material properties and processing requirements, adjustable laser wavelength and power can significantly increase the processing speed. The adjustable laser system provides greater flexibility for different manufacturing needs. Different process steps, such as cutting, melting and removal, can be optimized and adjusted according to actual conditions, so that various process requirements can be quickly responded to during the production process and adapted to diverse product designs. At the same time, by optimizing the laser wavelength and power, material waste and processing time can be reduced, thereby reducing production costs. Effective processing strategies and flexible parameter settings can help manufacturers achieve higher production efficiency while maintaining high quality.

[0073] In some embodiments, the first laser, the second laser, and the third laser spray inert gas or protective gas during the cutting process.

[0074] During the cutting process of the first laser, the second laser, and the third laser, the injection of inert gas or protective gas significantly improves the processing effect and the quality of the silicon wafer 101. Inert gases such as nitrogen or helium effectively isolate oxygen, prevent oxidation reactions, and maintain the purity and electrical properties of the silicon wafer 101. At the same time, these gases can quickly take away the heat generated during the laser processing, reducing the risk of thermal damage and material deformation. In addition, the injection gas can also remove molten materials to prevent them from re-attaching to the surface of the silicon wafer 101, thereby ensuring a clean cutting edge and improving the cutting quality. This method not only optimizes the processing speed, but also enhances production efficiency and safety, so that the final product meets higher standards in performance and appearance.

[0075] The present application also provides a solar photovoltaic module, comprising a plurality of solar cells prepared by the method for preparing a selective emitter solar cell according to any of the aforementioned embodiments, and connected by transparent conductive materials, for converting sunlight into electrical energy to provide renewable electricity for various applications. Figure 8 FIG. 1 shows a schematic diagram of the structure of a solar photovoltaic assembly according to an embodiment of the present application. Figure 8 As shown, the solar photovoltaic module includes:

[0076] The cell array 201 includes a plurality of solar cells manufactured by the method for manufacturing a selective emitter solar cell according to any of the above embodiments, and the cells are connected via a transparent conductive material 202 .

[0077] In some embodiments, the transparent conductive material 202 may be indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), etc. These materials have both transparency and conductivity, ensuring that light can penetrate the material and reach the solar cell below, while being able to effectively conduct current.

[0078] The transparent adhesive film 203 is used to cover the surface of the battery array 201 .

[0079] The main function of the transparent adhesive film 203 is to protect the battery array 201 and ensure that the components are protected from external environmental factors such as moisture, dust, mechanical impact and other factors. The adhesive film plays a dual function of bonding and protection during the packaging process. It can firmly bond the battery cells, glass and backplane together during the high-temperature lamination process. Its high light transmittance ensures that sunlight can penetrate the adhesive film to the surface of the battery cells to the greatest extent, ensuring the efficient operation of the battery. At the same time, the adhesive film also prevents water vapor from entering, extending the life of the component. The transparent adhesive film 203 is usually made of materials such as ethylene vinyl acetate (EVA) and polyolefin elastomer (POE), which have good light transmittance, weather resistance and adhesion properties.

[0080] The substrate 204 is used to cover the two opposite sides of the transparent adhesive film 203 and the battery array 201 .

[0081] The main function of the substrate 204 is to provide mechanical support and protection for the solar photovoltaic module, to protect the transparent adhesive film 203 and the battery array 201 from the external environment, and to prevent mechanical damage, moisture, ultraviolet rays and other factors from causing the performance of the module to deteriorate. In addition, the substrate 204 also enhances the structural stability of the module and helps to extend the service life of the module. The material of the substrate 204 is generally glass or a polymer composite material. The former is the commonly selected tempered / semi-tempered glass with high strength and durability; the latter may be a backplane film, such as polyvinyl fluoride (PVF) or polyvinylidene fluoride (PVDF), or it may be tempered / semi-tempered glass with excellent waterproofness and weather resistance.

[0082] It should be noted that, for the parts that are the same as or corresponding to the above-mentioned embodiments, reference may be made to the corresponding description of the above-mentioned embodiments, and will not be described in detail below.

[0083] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0084] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A method for preparing a selective emitter solar cell, characterized in that: The method comprises: printing a dopant paste layer on the front side of the silicon wafer and depositing an organic layer on the dopant paste layer; Using a first laser to cut the organic layer, so that the organic layer has an opening, exposing a corresponding area of ​​the dopant paste layer; Using a second laser to melt the area of ​​the dopant slurry layer corresponding to the exposed opening, so that the area corresponding to the opening on the silicon wafer is heavily doped; Using a third laser to remove the area corresponding to the dopant paste layer exposed at the opening, exposing an area corresponding to the passivation contact structure on the front side, wherein the first laser, the second laser and the third laser are formed by the same laser system; The front side passivation contact structure is formed in the exposed area.

2. The method for preparing a selective emitter solar cell according to claim 1, characterized in that: Also includes: The dopant paste layer is printed multiple times on the front side of the silicon wafer, and the dopant content used in each printing is gradually reduced.

3. The method for preparing a selective emitter solar cell according to claim 2, characterized in that: It also includes that the thickness of the dopant paste layer increases gradually each time it is printed.

4. The method for preparing a selective emitter solar cell according to claim 3, characterized in that: The dopant slurry layer is printed on the entire surface.

5. The method for preparing a selective emitter solar cell according to claim 3, characterized in that: The dopant slurry layer is partially printed, and the width of the dopant slurry layer is gradually increased each time it is printed.

6. The method for preparing a selective emitter solar cell according to claim 1, characterized in that: Also includes: Performing texturing on the front side of the silicon wafer; After the front surface is texturized, the area corresponding to the front surface passivation contact structure is polished.

7. The method for preparing a selective emitter solar cell according to claim 1, characterized in that: The laser wavelengths and powers of the first laser, the second laser and the third laser are adjustable.

8. The method for preparing a selective emitter solar cell according to claim 1, characterized in that: The first laser, the second laser and the third laser spray inert gas or protective gas during the cutting process.

9. A solar panel, characterized in that: include: A battery array comprising a plurality of solar cells prepared according to the method for preparing a selective emitter solar cell according to any one of claims 1 to 8, and connected by a transparent conductive material; A transparent adhesive film, used to cover the surface of the battery array; The substrate is used to cover the two sides of the transparent adhesive film opposite to the battery array.

Images