Manufacturing method of solar cell and solar cell

Abstract

Embodiments of the present disclosure relate to the field of photovoltaics, and provide a method for manufacturing a solar cell and a solar cell. The method for manufacturing a solar cell may include: providing an initial substrate; performing a texturing process to form a pyramid structure on the surface of the initial substrate; forming a hydrogen storage material layer that covers the surface of the pyramid structure, and the hydrogen storage material layer includes: a surface layer and hydrogen ions encapsulated within the surface layer; performing a decomposition process, which is used to decompose the surface layer of the hydrogen storage material layer to separate from the surface of the pyramid structure, and release the hydrogen ions stored within the surface layer to the surface of the initial substrate to achieve hydrogen passivation. The reliability of the formed pyramid structure can be improved.

Description

Technical Field

[0001] The present disclosure relates to the field of photovoltaics, and particularly to a method for manufacturing a solar cell and a solar cell. Background Art

[0002] A solar cell is a thin photoelectric semiconductor sheet that directly generates electricity using sunlight, also known as a "solar chip" or "photovoltaic cell". As long as it is illuminated by light with a certain illumination intensity, it can instantaneously output voltage and generate current in the presence of a circuit. In physics, it is called solar photovoltaic (abbreviated as PV), simply referred to as photovoltaic.

[0003] Currently, in order to improve the light absorption ability of solar cells, a pyramid structure is also formed on the surface of the substrate. The pyramid structure is used to reflect the light passing through the substrate back into the substrate again, thereby improving the light absorption ability of the solar cell. Summary of the Invention

[0004] Embodiments of the present disclosure provide a method for manufacturing a solar cell and a solar cell, which can at least improve the reliability of the solar cell while improving the light absorption ability of the solar cell.

[0005] According to some embodiments of the present disclosure, on the one hand, an embodiment of the present disclosure provides a method for manufacturing a solar cell, including: providing an initial substrate; performing texturing treatment to form a pyramid structure on the surface of the initial substrate; forming a hydrogen storage material layer, the hydrogen storage material layer covering the surface of the pyramid structure, and the hydrogen storage material layer including: a surface layer and hydrogen ions wrapped in the surface layer; performing a decomposition process, the decomposition process being used to decompose the surface layer of the hydrogen storage material layer to separate from the surface of the pyramid structure and release the hydrogen ions in the surface layer to the surface of the initial substrate to achieve hydrogen passivation.

[0006] In some embodiments, the material of the hydrogen storage material layer includes: carbon nanotubes, and hydrogen ions are stored in the pores of the carbon nanotubes.

[0007] In some embodiments, the decomposition process includes heat treatment.

[0008] In some embodiments, the process parameters of the heat treatment include: the heating temperature is 1000°C to 1200°C, the heating duration is 3000s to 4000s, the gas flow rate of oxygen is 10000sccm to 13000sccm, and the gas flow rate of nitrogen is 3500 sccm to 6000sccm.

[0009] In some embodiments, the decomposition process includes a laser process that irradiates the surface of the hydrogen storage material layer with a laser and bombards the hydrogen ions to the surface of the pyramid structure.

[0010] In some embodiments, the process parameters of the laser process include: the laser power is 20W - 40W, and the laser width is 90μm - 110μm.

[0011] In some embodiments, the surface density of the hydrogen storage material layer is 500 kg / m 3 ~700 kg / m 3 and the density of hydrogen ions in the surface layer is 30 kg / m 3 ~50 kg / m 3 .

[0012] In some embodiments, the pyramid structure includes: a tower body and a tower tip located on the top surface of the tower body. The method for forming the hydrogen storage material layer includes: forming a first hydrogen storage material layer that covers the surfaces of the tower body and the tower tip; forming a second hydrogen storage material layer that covers at least the surface of the first hydrogen storage material layer corresponding to the tower tip.

[0013] In some embodiments, the processes for forming the first hydrogen storage material layer and the second hydrogen storage material layer include: a spin coating process that is used to form the first hydrogen storage material layer on the surface of the pyramid structure; a chemical vapor deposition process. The second hydrogen storage material layer formed by the chemical vapor deposition process also covers the surface of the first hydrogen storage material layer corresponding to the tower body, and the thickness of the second hydrogen storage material layer corresponding to the tower tip is greater than the thickness of the second hydrogen storage material layer corresponding to the tower body.

[0014] According to some embodiments of the present disclosure, on the other hand, the present disclosure also provides a solar cell formed by the method for manufacturing a solar cell as described above.

[0015] The technical solutions provided by the embodiments of the present disclosure have at least the following advantages: First, a pyramid structure is formed on the surface of the initial substrate. Taking the formation of the pyramid structure on the front side as an example, the light reflected on the front side is reflected back into the substrate again by the side walls of the pyramid structure through the pyramid structure, thereby improving the light absorption capacity of the battery chip. However, during the process of forming the pyramid structure, inevitably, the side walls of the pyramid structure will be eroded, resulting in defects in the morphology of the pyramid structure. These defects will cause the light absorption capacity improvement of the pyramid structure to decline. Therefore, a hydrogen storage material layer is first formed on the surface of the pyramid structure, and the hydrogen element stored in the hydrogen storage material layer is released by means of a decomposition process. On the one hand, the hydrogen storage material layer will not remain on the surface of the pyramid structure after the decomposition process. On the other hand, the released hydrogen element will perform hydrogen passivation on the surface of the initial substrate, thereby repairing the defects on the surface of the pyramid structure and improving the reliability of the formed battery chip. Description of the Drawings

[0016] One or more embodiments are exemplarily illustrated by the pictures in the corresponding accompanying drawings. These exemplary illustrations do not limit the embodiments unless otherwise stated. The figures in the accompanying drawings do not constitute a proportional limitation; in order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or in the prior art, the accompanying drawings required for use in the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other accompanying drawings can be obtained based on these drawings without creative efforts.

[0017] Figures 1 to 5 Structural schematic diagrams corresponding to the steps of a method for manufacturing a solar cell chip provided by an embodiment of the present disclosure.

[0018] Description of the Reference Numerals:

[0019] 100, initial substrate; 101, pyramid structure; 102, hydrogen storage material layer; 103, emitter; 104, first passivation layer; 105, first electrode; 106, tunneling layer; 107, doped conductive layer; 108, second passivation layer; 109, second electrode. Detailed Embodiments

[0020] As can be seen from the background art, currently, damage will be caused to the substrate while forming the pyramid structure, and this part of the damage will lead to the compatibility of the effect of forming the morphology of the pyramid structure.

[0021] An embodiment of the present disclosure provides a method for manufacturing a solar cell. First, a pyramid structure is formed on the surface of an initial substrate. Taking the formation of a pyramid structure on the front surface as an example, the light reflected on the front surface is reflected back into the substrate again by the side walls of the pyramid structure through the pyramid structure, thereby improving the light absorption capacity of the solar cell. Also, a hydrogen storage material layer is first formed on the surface of the pyramid structure, and by means of a decomposition process, the hydrogen element stored in the hydrogen storage material layer is released. On the one hand, the hydrogen storage material layer will not remain on the surface of the pyramid structure after the decomposition process. On the other hand, the released hydrogen element will perform hydrogen passivation on the surface of the initial substrate, thereby repairing the defects on the surface of the pyramid structure and improving the reliability of the formed solar cell.

[0022] In the description of the embodiments of the present disclosure, technical terms such as "first" and "second" are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity, specific order, or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present disclosure, the meaning of "a plurality" is more than two, unless otherwise clearly and specifically defined.

[0023] Referring to "embodiment" herein means that a specific feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present disclosure. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0024] In the description of the embodiments of the present disclosure, the term "and / or" is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: there is A, there is both A and B, and there is B. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0025] In the description of the embodiments of the present disclosure, the term "a plurality" refers to more than two (including two). Similarly, "a plurality of groups" refers to more than two groups (including two groups), and "a plurality of pieces" refers to more than two pieces (including two pieces).

[0026] In the description of the embodiments of the present disclosure, the orientation or positional relationship indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the embodiments of the present disclosure.

[0027] In the description of the embodiments of the present disclosure, unless otherwise clearly specified and limited, technical terms such as "install", "connect", "couple", "fix", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to specific situations.

[0028] In the corresponding drawings of the embodiments of the present disclosure, for better understanding and convenience of description, the thickness and area of the layer are enlarged. When describing a component (such as a layer, film, region, or substrate) on or on the surface of another component, the component can be "directly" on the surface of the other component, or there can be a third component between the two components. On the contrary, when describing a component on the surface of another component or when another component is formed or provided on the surface of a component, it means that there is no third component between the two components. In addition, when describing a component "substantially" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor on a partial edge of the entire surface.

[0029] In the description of the embodiments of the present disclosure, when a certain component "includes" another component, unless otherwise stated, other components are not excluded, and other components may further be included. In addition, when a component such as a layer, film, region, or plate is referred to as "on / at" another component, it can be "directly on" the other component (i.e., on the surface of the other component and there is no other component between them), or there can be another component between them. In addition, when a layer, film, region, plate, etc. component is "directly located on" another component, or when a layer, film, region, plate, etc. component is located on the surface of another component, it means that there is no other component located between them.

[0030] The terms used in the description of the various embodiments herein are for the purpose of describing particular embodiments only and are not intended to be limiting. As used in the description of the various embodiments and the appended claims, "the component" is also intended to include the plural form unless the context clearly indicates otherwise. Among them, the component includes components such as layers, films, regions, or plates.

[0031] The various embodiments of the present disclosure will be described in detail below in conjunction with the accompanying drawings. However, those of ordinary skill in the art can understand that in the various embodiments of the present disclosure, many technical details are provided to help readers better understand the present disclosure. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present disclosure can still be implemented.

[0032] The following will be combined with Figures 1 to 5 to illustrate a method for manufacturing a battery cell provided in an embodiment of the present disclosure. Figures 1 to 5 FIG. [X] is a schematic structural diagram corresponding to each step of a method for manufacturing a battery cell provided in an embodiment of the present disclosure.

[0033] In some embodiments, the method for manufacturing a battery cell may include: providing an initial substrate 100.

[0034] The method for manufacturing a battery cell may further include: performing a texturing process to form a pyramid structure 101 on the surface of the initial substrate 100.

[0035] The method for manufacturing a battery cell may further include: forming a hydrogen storage material layer 102, the hydrogen storage material layer 102 covering the surface of the pyramid structure 101, and the hydrogen storage material layer 102 including: a surface layer and hydrogen ions wrapped in the surface layer.

[0036] The method for manufacturing a battery cell may further include: performing a decomposition process, the decomposition process being used to decompose the surface layer of the hydrogen storage material layer 102 to separate from the surface of the pyramid structure 101 and release the hydrogen ions in the surface layer to the surface of the initial substrate 100 to achieve hydrogen passivation.

[0037] Note: In , since the specific figure number is not provided in the original text, [X] is used as a placeholder.An embodiment of the present disclosure provides a method for manufacturing a solar cell. First, a pyramid structure 101 is formed on the surface of an initial substrate 100. Taking the formation of the pyramid structure 101 on the front side as an example, the light reflected on the front side is reflected back into the substrate again by the side walls of the pyramid structure 101, thereby improving the light absorption ability of the solar cell. Also, a hydrogen storage material layer 102 is first formed on the surface of the pyramid structure 101, and the hydrogen element stored in the hydrogen storage material layer 102 is released by means of a decomposition process. On the one hand, the hydrogen storage material layer 102 will not remain on the surface of the pyramid structure 101 after the decomposition process. On the other hand, the released hydrogen element will perform hydrogen passivation on the surface of the initial substrate 100, thereby repairing the defects on the surface of the pyramid structure 101 and improving the reliability of the formed solar cell.

[0038] Reference Figure 1 , Figure 1 is a schematic structural diagram of an initial substrate provided by an embodiment of the present disclosure.

[0039] In some embodiments, before the texturing process, a pre-cleaning process is also included for the initial substrate 100. Through the pre-cleaning process, dirt particles and minor damages on the surface of the initial substrate 100 can be removed, which is beneficial to the uniformity of the morphology of the pyramid structure 101 formed by the subsequent texturing process and reduces the defects formed by the texturing process.

[0040] In some embodiments, the pre-cleaning process can be carried out using an alkaline solution, such as sodium hydroxide solution or potassium hydroxide solution, etc.

[0041] Taking the sodium hydroxide solution as an example, the mass concentration of sodium hydroxide in the pre-cleaning process is 2% - 10%. If the mass concentration of the pre-cleaning solution is less than 2%, the removal effect of dirt particles and minor damages on the surface of the initial substrate 100 is not good; if the mass concentration of the pre-cleaning solution is greater than 10%, the reaction rate is not easy to control, and the corrosion rate of the initial substrate 100 is too fast. When the mass concentration of the pre-cleaning solution is in the range of 2% - 10%, a balance can be achieved between effectively removing dirt particles and minor damages on the surface of the initial substrate 100 and minimizing the damage to the initial substrate 100.

[0042] In some embodiments, after the pre-cleaning process, the initial substrate 100 is also subjected to a water washing process. Through the water washing process, the remaining solution in the pre-cleaning process can be rinsed off, thereby facilitating the subsequent formation of the hydrogen storage material layer 102 and avoiding the influence of the pre-cleaning process on the subsequently formed hydrogen storage material layer 102.

[0043] Reference Figure 2 , Figure 2 For forming a pyramid structure on the basis of Figure 1 .

[0044] In some embodiments, the texturing process may include: an etching process that forms pyramid structures 101 on the surface of the initial substrate 100; a first cleaning process that is used to remove particles on the surface of the initial substrate 100 and reagents remaining from the etching process; and a second cleaning process that is used to remove reagents remaining from the first cleaning process.

[0045] It can be understood that the etching process is the step of forming the pyramid structures 101 in the texturing process. When the material of the initial substrate 100 is polysilicon, isotropic etching of the polysilicon is performed using an etching solution to form pyramid structures 101 on the surface of the polysilicon. When the material of the initial substrate 100 is monocrystalline silicon, anisotropic etching is performed using an etching solution. This etching causes the (100) crystal plane on the initial substrate 100 to be etched faster than the (111) crystal plane, thereby forming the surface of the pyramid structures 101.

[0046] The first cleaning process and the second cleaning process are used to clean the surface of the initial substrate 100 after the etching process, thereby facilitating the formation of the hydrogen storage material layer 102. Also, through the first cleaning process and the second cleaning process, it is avoided that impurities generated by the etching process affect subsequent process steps, such as avoiding the generated impurities from affecting the formation of the hydrogen storage material layer 102 and so on.

[0047] In some embodiments, the etching process may use a sodium hydroxide solution to etch the surface of the initial substrate 100, and the mass percentage concentration of sodium hydroxide is 1% - 3%. It can be understood that when the mass percentage concentration of sodium hydroxide is set to be less than 1%, the formed pyramid structures 101 are not good; when the mass percentage concentration of sodium hydroxide is set to be greater than 3%, there may be over-etched pyramid structures 101.

[0048] In some embodiments, an etching aid is further added during the etching process, and the mass percentage of the etching aid may be 0.3% - 1%. The etching aid is used to improve the wettability of the sodium hydroxide solution with the surface of the initial substrate 100, and the etching aid can have a buffering effect during the transport process of hydroxide ions in the etching solution from the sodium hydroxide solution to the reaction interface, thereby stabilizing the solution system, extending the solution failure period, stabilizing the process, and broadening the process tolerance range. When the mass percentage concentration of the etching aid is less than 0.3%, the improvement effect of the etching aid is not good. When the mass percentage concentration of the etching aid is greater than 1%, the etching aid will inhibit the reaction process of the etching process, resulting in an increase in the process duration.

[0049] In some embodiments, the etching process may also use hydrofluoric acid or nitric acid solution to perform texturing treatment on the initial substrate 100. The principle is the same as that of the above-mentioned use of alkaline solution, and will not be elaborated here.

[0050] When the etching process uses an alkaline solution to etch the initial substrate 100, the first cleaning process can use an acidic solution to clean the surface of the initial substrate 100. On the one hand, it can neutralize the residual alkaline solution from the etching process. On the other hand, it is also beneficial to dissolve the by-products formed during the etching process, thereby improving the cleanliness of the surface of the initial substrate 100. When the etching process uses an acidic solution to etch the initial substrate 100, the first cleaning process can use an alkaline solution to clean the surface of the initial substrate 100. Similarly, the acidic solution is used to neutralize the residual acidic solution from the etching process, and at the same time, it also dissolves the by-products formed during the etching process, thereby improving the cleanliness of the surface of the initial substrate 100.

[0051] When the etching process uses an alkaline solution to etch the initial substrate 100, the first cleaning process uses an acidic solution, and the second cleaning process can use an alkaline solution, and the mass percentage concentration of the alkaline solution used in the second cleaning process is less than the mass percentage concentration of the alkaline solution used in the etching process. When the etching process uses an acidic solution to etch the initial substrate 100, the first cleaning process uses an alkaline solution, and the second cleaning process can use an acidic solution, and the mass percentage concentration of the acidic solution used in the second cleaning process is less than the mass percentage concentration of the acidic solution used in the etching process.

[0052] The second cleaning process is used to remove the reagent residue of the first cleaning process, and in order to reduce the residue of the second cleaning process, the mass percentage concentration of the reagent solute used in the second cleaning process is also reduced, thereby further improving the cleanliness of the surface of the initial substrate 100 after the second cleaning process.

[0053] In some embodiments, after the etching process, the first cleaning process, and the second cleaning process, deionized water is used to clean the surface of the initial substrate 100. In other words, the process of the texturing treatment is in sequence: etching process, deionized water cleaning, first cleaning process, deionized water cleaning, second cleaning process, and deionized water cleaning. Using deionized water for cleaning can prevent ions from remaining on the surface of the initial substrate 100.

[0054] In some embodiments, the surface of the initial substrate 100 can be cleaned with deionized water at room temperature, and the cleaning time can be 60s - 100s. It can be understood that if the cleaning time is less than 60s, there may be a problem of incomplete cleaning. If the cleaning time is greater than 100s, it will cause too long cleaning time, resulting in an increase in the cost of forming the solar cell.

[0055] Reference Figure 3 , Figure 3 For forming a hydrogen storage material layer on the basis of Figure 2

[0056] The method for forming the hydrogen storage material layer 102 may include chemical vapor deposition, laser evaporation method or arc method, and the thickness of the formed hydrogen storage material layer 102 may be 100 μm to 300 μm, such as 100 μm, 150 μm, 200 μm, 220 μm, 250 μm, 280 μm or 300 μm. For the hydrogen storage material layer 102, the thicker the thickness of the hydrogen storage material layer 102, the more total amount of hydrogen elements stored, and the stronger the repair ability for the defects of the pyramid structure 101. Similarly, the thicker the thickness of the hydrogen storage material layer 102, the higher the time and temperature required for the subsequent decomposition process, resulting in the subsequent process becoming uncontrollable, and it is easy to cause that part of the hydrogen storage material layer 102 will not be completely decomposed during the decomposition process, affecting the formation of the subsequent structure layer.

[0057] In some embodiments, the surface density of the hydrogen storage material layer 102 is 500 kg / m 3 ~700 kg / m 3 , and the density of hydrogen ions in the surface layer is 30 kg / m 3 ~50 kg / m 3 , since the hydrogen storage material layer 102 includes: a surface layer and hydrogen ions stored in the surface layer, wherein the surface layer wraps the hydrogen ions. Here, the surface density refers to the weight per unit area of the part of the hydrogen storage material layer 102 excluding hydrogen ions, and the hydrogen ions in the surface layer herein refer to the content of hydrogen ions per unit area only within the hydrogen storage material layer 102.

[0058] In some embodiments, the material of the hydrogen storage material layer 102 includes: carbon nanotubes, and hydrogen ions are stored in the pores of the carbon nanotubes.

[0059] It can be understood that carbon nanotubes have characteristics such as a large specific surface area, high chemical stability, and adjustable pore size, providing a good basis for their use as hydrogen storage materials. Since hydrogen ions are small, a highly adjustable pore size is required to adsorb and store hydrogen. Carbon nanotubes can adjust their pore size during the hydrogen storage process, and the pore size in both the horizontal and vertical directions can be adjusted. In addition, the interior of carbon nanotubes exhibits a highly ordered arrangement structure and has good mechanical strength, capable of stably storing hydrogen.

[0060] Carbon nanotubes adsorb hydrogen molecules to their interior or surface through van der Waals forces, electrostatic forces, chemical reactions and other acting forces. Compared with traditional hydrogen storage technologies, carbon nanotubes have stronger hydrogen adsorption ability, can achieve a higher hydrogen storage density under normal temperature and pressure, and can also realize faster adsorption and desorption processes. In addition, carbon nanotubes improve the hydrogen storage efficiency and reversibility by controlling their pore size. Therefore, carbon nanotubes have excellent hydrogen storage performance due to their structural characteristics.

[0061] In some embodiments, the pore diameter of the carbon nanotube material is 2 nm to 20 nm. The larger the pore diameter of the carbon nanotube material, the more hydrogen ions it stores. However, for the substrate, there is an upper limit to the passivation effect that can be passivated by hydrogen ions. An overly large pore diameter will result in waste of materials and costs. Therefore, setting the pore diameter of the carbon nanotube material to 2 nm to 20 nm can control the cost of the manufacturing method of the solar cell while passivating the substrate.

[0062] In some embodiments, the pyramid structure 101 includes: a tower body and a tower tip located on the top surface of the tower body. The method for forming the hydrogen storage material layer 102 includes: forming a first hydrogen storage material layer that covers the surfaces of the tower body and the tower tip; forming a second hydrogen storage material layer that covers at least the surface of the first hydrogen storage material layer corresponding to the tower tip.

[0063] It can be understood that during the texturing process, the part of the tower tip is more likely to be damaged. Therefore, for the tower tip, a second hydrogen storage material is also provided to increase the content of hydrogen elements in the part of the tower tip, so as to repair the tower tip with more hydrogen elements.

[0064] Moreover, compared with directly introducing hydrogen or directly using plasma hydrogen passivation, it is difficult to perform local hydrogen passivation on the tower tip of the pyramid structure 101 by directly introducing hydrogen or using plasma hydrogen passivation. That is to say, for the microscopic morphology of the pyramid structure 101, the methods of using hydrogen and plasma hydrogen often bring about overall passivation along with the diffusion of gas or the injection of plasma, and it is very difficult to perform hydrogen passivation on only the part of the tower tip. By using the method of forming the first hydrogen storage material layer and the second hydrogen storage material layer, since the formation of the second hydrogen storage material layer will inevitably result in a higher concentration of hydrogen elements at the position corresponding to the tower tip, it will inevitably bring about a better repair effect on the tower tip, thus achieving the purpose of different repair effects for the tower tip and the tower body.

[0065] In some embodiments, the processes for forming the first hydrogen storage material layer and the second hydrogen storage material layer include: a spin coating process for forming the first hydrogen storage material layer on the surface of the pyramid structure 101; a chemical vapor deposition process, and the second hydrogen storage material layer formed by the chemical vapor deposition process also covers the surface of the first hydrogen storage material layer corresponding to the tower body, and the thickness of the second hydrogen storage material layer at the position corresponding to the tower tip is greater than the thickness of the second hydrogen storage material layer at the position corresponding to the tower body.

[0066] It can be understood that for the spin-coating process, the spin-coating process uses centrifugal force to push the first hydrogen storage material layer to spread on the surface of the initial substrate 100. At the same time, the viscous resistance and surface tension of the fluid begin to act to control the flow and spreading of the liquid. The thickness of the coating film gradually stabilizes over time and with the change of the rotation speed, forming a thin film with a uniform thickness and a smooth surface. Therefore, a relatively uniform first hydrogen storage material layer can be formed on the surface of the pyramid structure 101 through the spin-coating process. For the chemical vapor deposition process, the chemical vapor deposition process is a process that uses gaseous substances to undergo chemical reactions and transport reactions on the surface of the initial substrate 100 and produce solid deposits. However, for the chemical vapor deposition process, the formed gaseous substances will preferentially adhere to the tip part. Therefore, the thickness of the second hydrogen storage material corresponding to the tip position will be greater than the thickness of the second hydrogen storage material layer corresponding to the tower body position. Generally speaking, there is relatively more hydrogen storage material layer 102 attached to the steps. In this way, it can be realized that the repair effect of hydrogen ions on the tip is better, so as to further improve the reliability of the subsequent formed battery chip.

[0067] Reference Figure 4 , Figure 4 For the decomposition process on the basis of Figure 3 .

[0068] In some embodiments, the decomposition process includes heat treatment. As the temperature rises, the hydrogen in the carbon nanotubes will detach from the carbon nanotubes to passivate the initial substrate 100, thereby improving the reliability of the formed pyramid structure 101.

[0069] In some embodiments, the process parameters of the heat treatment include: the heating temperature is 1000°C to 1200°C, the heating duration is 3000 s to 4000 s, the gas flow rate of oxygen is 10000 sccm to 13000 sccm, and the gas flow rate of nitrogen is 3500 sccm to 6000 sccm.

[0070] It can be understood that after the temperature exceeds 1000°C, carbon reacts with oxygen to generate carbon dioxide, so that the energy storage material layer detaches from the surface of the initial substrate 100. Using the gas flow rate of oxygen of 10000 sccm to 13000 sccm can make carbon react fully with oxygen to generate carbon dioxide instead of generating toxic gas such as carbon monoxide, thereby improving the reliability of the manufacturing method.

[0071] For the heating temperature, if the heating temperature is less than 1000°C, it will cause insufficient reaction of carbon and lead to the residue of the hydrogen storage material layer 102. If the heating temperature is greater than 1200°C, on the one hand, it will increase the process difficulty, and on the other hand, it will cause process waste.

[0072] Regarding the heating time, similarly, if the heating time is less than 3000 s, it may cause residues in the hydrogen storage material layer 102. If the heating time is greater than 4000 s, it will result in waste of the process duration and increase the cost of forming the solar cell.

[0073] Regarding nitrogen gas, by introducing nitrogen gas, impurity gases in the decomposition process can be removed, so that the decomposition process is in an inert environment, thereby improving reliability.

[0074] In some embodiments, the heat treatment may further include two stages. Among them, the first stage is used to control the detachment of hydrogen ions from the carbon nanotubes. During this process, only nitrogen gas can be introduced. By introducing nitrogen gas, it is ensured that the hydrogen ion passivation process will not be interfered by impurity gases, thereby improving the reliability of the entire decomposition process; the second stage is used to control the reaction of the hydrogen storage material layer 102 with oxygen to generate carbon dioxide.

[0075] In some embodiments, the process parameters of the first stage may include: the heating temperature is 300 °C to 1000 °C, and the gas flow rate of the introduced nitrogen gas is 3500 sccm to 6000 sccm.

[0076] In some embodiments, the decomposition process includes a laser process. The laser process irradiates the surface of the hydrogen storage material layer 102 with a laser and bombards the hydrogen ions to the surface of the pyramid structure 101. The laser process can also achieve the purpose of hydrogen passivation. Moreover, the hydrogen storage material layer 102 can also serve as a protective layer, thereby reducing the damage of the laser to the substrate. After the hydrogen passivation is completed, the hydrogen storage material layer 102 is removed for subsequent process steps.

[0077] In some embodiments, the repair effect can also be controlled by controlling the local irradiation time of the laser process. For example, the pyramid structure 101 includes a tower body and a tower tip. By increasing the time of irradiating the hydrogen storage material layer 102 corresponding to the tower tip position by the laser process, the repair effect of the position where the tower tip is located can be improved.

[0078] In some embodiments, the process parameters of the laser process include: the laser power is 20 W to 40 W, such as 22 W, 25 W, 28 W, 30 W, 35 W or 38 W, etc., and the laser width is 90 μm to 110 μm, such as 93 μm, 95 μm, 100 μm, 103 μm, 107 μm or 109 μm, etc.

[0079] Regarding the laser power, if the laser power is too large, it may cause damage to the hydrogen storage material layer and even damage to the substrate, which is not conducive to the hydrogen passivation of the substrate. If the power is too low, it may not be able to bombard the hydrogen ions well to the surface of the pyramid structure 101, resulting in a weak ability to improve the passivation effect.

[0080] The laser process can use red nano-laser, green nano-laser or purple nano-laser. Red nano-laser, green nano-laser or purple nano-laser all belong to nano-second laser, that is, the laser used in the laser activation process can be short-pulse laser.

[0081] In some embodiments, after the decomposition process, subsequent process steps are sequentially performed according to the types of solar cell wafers to be formed, such as forming a doped conductive layer, forming electrodes, and performing tests, etc.

[0082] Such as Figure 5 , Figure 5 Taking the formed solar cell wafer as a TOPCON cell as an example, Figure 5 After hydrogen passivation is completed, an emitter 103, a first passivation layer 104, a tunneling layer 106, a doped conductive layer 107, a second passivation layer 108, a first electrode 105, and a second electrode 109 are formed.

[0083] Among them, the emitter 103 covers the surface of the pyramid structure 101, the passivation layer covers the surface of the emitter 103, the first electrode is electrically connected to the emitter 103, the tunneling layer 106 covers the back surface of the substrate, the doped conductive layer 107 covers the surface of the tunneling layer 106, the second passivation layer 108 covers the surface of the doped conductive layer 107, and the second electrode 109 is electrically connected to the doped conductive layer 107.

[0084] It can be understood that, referring to the following table, for the solar cell wafers formed by the method for manufacturing cell wafers provided in the embodiments of the present disclosure, the cell efficiency increases by 0.05% - 0.07%, and the open-circuit voltage increases by 1 mV - 1.5 mV.

[0085]

[0086] It should be noted that the manufacturing methods of the solar cell wafers in the above control group and the experimental group are almost the same. The difference is that the experimental group forms a hydrogen storage material layer 102 and decomposes the hydrogen storage material layer through the decomposition process, while the control group does not form a hydrogen storage material layer. Then, under the same environmental conditions, after being irradiated with the same light, the above performance parameters are tested.

[0087] Among them, the test conditions can include: the environmental temperature is 23°C, the irradiation time is transient, and the light intensity is 1000 w / m 2 .

[0088] An embodiment of the present disclosure provides a method for manufacturing a solar cell. First, a hydrogen storage material layer 102 is formed on the surface of the pyramid structure 101, and the hydrogen element stored in the hydrogen storage material layer 102 is released by means of a decomposition process. On the one hand, the hydrogen storage material layer 102 will not remain on the surface of the pyramid structure 101 after the decomposition process. On the other hand, the released hydrogen element will passivate the surface of the initial substrate 100, thereby repairing the defects on the surface of the pyramid structure 101 and improving the reliability of the formed solar cell.

[0089] Another embodiment of the present disclosure further provides a solar cell, which can be formed by the formation method of the solar cell in the above-mentioned part or all of the embodiments. The solar cell provided in another embodiment of the present disclosure will be described below. It should be noted that for the same or corresponding parts in the foregoing embodiments, reference may be made to the corresponding descriptions in the foregoing embodiments, and the following will not be repeated.

[0090] In some embodiments, the solar cell includes, but is not limited to, a PERC (Passivated Emitter Rear Cell) cell, an IBC (Interdigitated Back Contact) cell, a TOPCon (Tunnel Oxide Passivated Contact) cell, a HIT / HJT (Heterojunction Technology) cell, a solar thin-film cell, or any combination of laminated cells. Among them, the solar thin-film cell includes, but is not limited to, a perovskite solar thin-film cell, a copper indium selenide solar thin-film cell, a gallium arsenide solar thin-film cell, and a cadmium sulfide solar thin-film cell. The laminated cell includes, but is not limited to, a perovskite cell stacked with a crystalline silicon cell, a perovskite cell stacked with a perovskite cell, and a perovskite cell stacked with a thin-film cell.

[0091] The solar cell can be a monocrystalline silicon solar cell, a polycrystalline silicon solar cell, an amorphous silicon solar cell, or a multi-component compound solar cell. The multi-component compound solar cell can specifically be a cadmium sulfide solar cell, a gallium arsenide solar cell, a copper indium selenide solar cell, or a perovskite solar cell. In addition, the solar cell can be a whole-cell or a sliced cell. The sliced cell refers to a cell formed by cutting a complete whole-cell through a cutting process.

[0092] Those of ordinary skill in the art can understand that the above embodiments are specific examples for implementing the present disclosure. In actual applications, various changes can be made to them in form and details without departing from the spirit and scope of the embodiments of the present disclosure. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of the present disclosure. Therefore, the protection scope of the embodiments of the present disclosure should be subject to the scope defined by the claims.

Claims

1. A method for manufacturing a solar cell, characterized in that, Including: Providing an initial substrate; Performing a texturing process to form a pyramid structure on the surface of the initial substrate; Forming a hydrogen storage material layer, the hydrogen storage material layer covering the surface of the pyramid structure, and the hydrogen storage material layer including: a surface layer and hydrogen ions wrapped within the surface layer; Performing a decomposition process, the decomposition process being used to decompose the surface layer of the hydrogen storage material layer to separate from the surface of the pyramid structure and release the hydrogen ions within the surface layer to the surface of the initial substrate to achieve hydrogen passivation.

2. The manufacturing method of the solar cell according to claim 1, characterized in that, The material of the hydrogen storage material layer includes: carbon nanotubes, and hydrogen ions are stored within the pores of the carbon nanotubes.

3. The manufacturing method of the solar cell according to claim 2, wherein The decomposition process includes a heat treatment.

4. The manufacturing method of the solar cell according to claim 3, characterized in that The process parameters of the heat treatment include: a heating temperature of 1000 °C to 1200 °C, a heating duration of 3000 s to 4000 s, a gas flow rate of oxygen being 10000 sccm to 13000 sccm, and a gas flow rate of nitrogen being 3500 sccm to 6000 sccm.

5. The manufacturing method of the solar cell according to claim 2, characterized in that, The decomposition process includes a laser process, the laser process irradiating the surface of the hydrogen storage material layer with a laser and bombarding the hydrogen ions to the surface of the pyramid structure.

6. The manufacturing method of the solar cell according to claim 5, characterized in that, The process parameters of the laser process include: a laser power of 20 W to 40 W and a laser width of 90 μm to 110 μm.

7. The manufacturing method of the solar cell according to claim 2, characterized in that, The surface density of the hydrogen storage material layer is 500 kg / m 3 ~700 kg / m 3 , and the density of hydrogen ions in the surface layer is 30 kg / m 3 ~50 kg / m 3 .

8. The manufacturing method of the solar cell according to claim 1, characterized in that, The pyramid structure includes: a tower body and a tower tip located on the top surface of the tower body. The method for forming the hydrogen storage material layer includes: Forming a first hydrogen storage material layer, the first hydrogen storage material layer covering the surfaces of the tower body and the tower tip; Forming a second hydrogen storage material layer, the second hydrogen storage material layer covering at least the surface corresponding to the tower tip of the first hydrogen storage material layer.

9. The manufacturing method of the solar cell according to claim 8, wherein, The processes for forming the first hydrogen storage material layer and the second hydrogen storage material layer include: A spin coating process, the spin coating process being used to form the first hydrogen storage material layer on the surface of the pyramid structure; A chemical vapor deposition process, the second hydrogen storage material layer formed by the chemical vapor deposition process further covering the surface corresponding to the tower body of the first hydrogen storage material layer, and the thickness of the second hydrogen storage material layer corresponding to the tower tip is greater than the thickness of the second hydrogen storage material layer corresponding to the tower body.

10. A solar cell, characterized in that, The solar cell is formed by using the manufacturing method of the solar cell according to any one of claims 1 to 9.

Images