Film manufacturing method, solar cell, solar power generation module, and solar power generation system

Abstract

To provide a film manufacturing method, a solar cell, a solar power generation module, and a solar power generation system that achieve both film passivation effect and manufacturing efficiency.SOLUTION: A manufacturing method includes forming a first passivation layer on a first surface of a substrate using a first manufacturing process, and forming a second passivation layer on the surface of the first passivation layer facing away from the substrate using a second manufacturing process, the material of the second passivation layer is the same as the material of the first passivation layer, the passivation layer manufacturing speed of the first manufacturing process is smaller than the passivation layer manufacturing speed of the second manufacturing process, and the passivation effect of the first passivation layer is better than the passivation effect of the second passivation layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present application relates to the technical field of film manufacturing, and in particular to a film manufacturing method, a solar cell, a photovoltaic module, and a photovoltaic system. [Background technology]

[0002] With the continuous development of semiconductor technology, people's demands for the performance of semiconductor devices are also increasing. Among these, passivation is a technology that significantly improves device performance. For example, forming a passivation layer in solar cells can significantly improve the photoelectric conversion efficiency of the solar cells. However, forming a passivation layer with excellent passivation effect will affect device manufacturing efficiency to some extent, causing a shortage of device production capacity. Summary of the Invention [Problem to be solved by the invention]

[0003] In view of this, it is necessary to provide a film manufacturing method, a solar cell, a photovoltaic power generation module, and a photovoltaic power generation system that can achieve both the passivation effect of the film and manufacturing efficiency in order to address the above technical problems. [Means for solving the problem]

[0004] In a first aspect, the present application provides a method for producing a film, the method comprising: forming a first passivation layer on a first surface of a substrate using a first manufacturing process; forming a second passivation layer on a surface of the first passivation layer away from the substrate using a second manufacturing process, the material of the second passivation layer being the same as the material of the first passivation layer; The passivation layer manufacturing rate of the first manufacturing process is lower than that of the second manufacturing process, and the passivation effect of the first passivation layer is better than that of the second passivation layer.

[0005] In one embodiment, the passivation effect of the first passivation layer being better than the passivation effect of the second passivation layer includes the hydrogen content of the first passivation layer being smaller than the hydrogen content of the second passivation layer, and / or the negative charge density of the first passivation layer being larger than the negative charge density of the second passivation layer.

[0006] In one embodiment, the first thickness of the first passivation layer is less than the second thickness of the second passivation layer.

[0007] In one embodiment, the first thickness of the first passivation layer is between 2 nm and 6 nm.

[0008] In one embodiment, the first fabrication process includes atomic layer deposition.

[0009] In one embodiment, forming a first passivation layer on a first surface of a substrate using the first manufacturing process includes: introducing a first precursor into a reaction chamber in which the substrate is located; After a first predetermined time has elapsed, the first precursor is discharged from the reaction chamber and a second precursor is introduced, the second precursor reacting with the first precursor to produce the first passivation layer; After a second predetermined time has elapsed, discharging the second precursor from the reaction chamber; and repeating the above until the thickness of the first passivation layer reaches the first thickness.

[0010] In one embodiment, forming a first passivation layer on a first surface of a substrate using a first manufacturing process includes: The substrate is controlled to move and pass through a first jet region into which a first precursor is introduced, a second jet region into which an isolation gas is introduced, and a third jet region into which a second precursor is introduced, in that order, the second precursor reacts with the first precursor to generate the first passivation layer, and the isolation gas acts as a partition to inhibit the reaction of the first precursor and the second precursor in regions other than the first surface of the substrate; and repeating the above until the thickness of the first passivation layer reaches the first thickness.

[0011] In one embodiment, forming a first passivation layer on a first surface of a substrate using the first manufacturing process includes: The substrate is controlled to move and pass through a first jet region into which a first precursor is introduced, an exhaust region, and a third jet region into which a second precursor is introduced, the second precursor reacting with the first precursor to generate the first passivation layer; and repeating the above until the thickness of the first passivation layer reaches the first thickness.

[0012] In one embodiment, forming a first passivation layer on a first surface of a substrate using the first manufacturing process includes: The substrate is controlled to move and pass through a first jet region into which a first precursor is introduced and a third jet region into which a second precursor is introduced, the second precursor reacting with the first precursor to generate the first passivation layer, and a distance between the first jet region and the third jet region is determined by a jet flow rate and / or a jet pressure of the first precursor and the second precursor; The above is repeated until the thickness of the first passivation layer reaches the first thickness.

[0013] In one embodiment, when forming a first passivation layer on a first surface of a substrate using the first manufacturing process, the first passivation layer is further formed on a peripheral surface of the substrate, and the peripheral surface is continuous with the first surface.

[0014] In one embodiment, the second manufacturing process comprises plasma enhanced chemical vapor deposition or alternating plasma enhanced chemical vapor deposition and atomic layer deposition.

[0015] In one embodiment, the material of the first passivation layer and the material of the second passivation layer are both alumina.

[0016] In a second aspect, the present application provides a solar cell, the solar cell including a substrate, and a first passivation layer and a second passivation layer formed by fabricating using the fabrication method described above.

[0017] In a third aspect, the present application provides a solar cell, the solar cell comprising: A substrate; a first passivation layer disposed on a first surface of the substrate; a second passivation layer provided on a surface of the first passivation layer away from the substrate; the material of the second passivation layer is the same as the material of the first passivation layer; The hydrogen content of the first passivation layer is lower than the hydrogen content of the second passivation layer, and / or the negative charge density of the first passivation layer is higher than the negative charge density of the second passivation layer.

[0018] In one embodiment, the first thickness of the first passivation layer is less than the second thickness of the second passivation layer.

[0019] In one embodiment, the first thickness of the first passivation layer is between 2 nm and 6 nm.

[0020] In one embodiment, the first passivation layer is further provided on a peripheral surface of the substrate, the peripheral surface being continuous with the first surface.

[0021] In one embodiment, the material of the first passivation layer and the material of the second passivation layer are both alumina.

[0022] In a fourth aspect, the present application provides a photovoltaic module, the photovoltaic module including a cell string, the cell string being formed by connecting a plurality of the solar cells described above.

[0023] In a fifth aspect, the present application provides a solar power generation system, the solar power generation system including the solar power generation module described above. [Effects of the Invention]

[0024] The film manufacturing method involves forming a first passivation layer on a first surface of a substrate using a first manufacturing process, and then forming a second passivation layer on the surface of the first passivation layer facing away from the substrate using a second manufacturing process. The second passivation layer and the first passivation layer are made of the same material, which allows the unified first and second passivation layers to be more easily applied to the manufacturing processes of other film layers in a device. Furthermore, even if the materials are the same, the first and second passivation layers have different passivation effects due to differences in the film formation effects of different manufacturing processes. Specifically, the passivation effect of the first passivation layer is superior to that of the second passivation layer, allowing the first passivation layer, which is closer to the substrate, to effectively passivate the substrate and ensure device performance. Furthermore, because the passivation layer production speed of the second manufacturing process is faster than that of the first manufacturing process, the second manufacturing process can be used to quickly increase the overall thickness of the passivation film including the first and second passivation layers until it reaches the target thickness, thereby ensuring sufficient reliability of the passivation film having the target thickness. Therefore, the film manufacturing method of the present application can combine the advantages of the first and second manufacturing processes, effectively achieving both the overall passivation effect of the manufactured film and manufacturing efficiency. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a flowchart of a method for manufacturing a film in one embodiment. [Figure 2] 1 is a cross-sectional view of a solar cell according to an embodiment of the present invention; [Figure 3] FIG. 10 is a cross-sectional view of a solar cell according to another embodiment. [Figure 4] 1 is a flow chart for forming a first passivation layer on a first surface of a substrate using a first manufacturing process in one embodiment. [Figure 5]10 is a flowchart illustrating forming a first passivation layer on a first surface of a substrate using a first manufacturing process in another embodiment. [Figure 6] FIG. 2 is a schematic diagram of an arrangement of jet heads in one embodiment. [Figure 7] FIG. 10 is a schematic diagram of an arrangement of jet heads in another embodiment. [Figure 8] 10 is a flowchart illustrating forming a first passivation layer on a first surface of a substrate using a first manufacturing process in another embodiment. [Figure 9] FIG. 10 is a schematic diagram of an arrangement of jet heads in another embodiment. [Figure 10] 10 is a flowchart illustrating forming a first passivation layer on a first surface of a substrate using a first manufacturing process in another embodiment. [Figure 11] FIG. 10 is a schematic diagram of an arrangement of jet heads in another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0026] In order to clarify the purpose, technical solution and advantages of the present application, the present application will be described in more detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only used to interpret the present application, and are not used to limit the present application.

[0027] The embodiments of the present application provide a film manufacturing method, which can be used to form a passivation layer on a substrate surface to improve the performance of a semiconductor device. Here, the semiconductor device can be, but is not limited to, a photovoltaic device. The photovoltaic device can include a photovoltaic cell, a semiconductor light-emitting device, etc., and the photovoltaic cell can be, for example, a solar cell. In each embodiment of the present application, the film manufacturing method is described as being used to form a passivation layer of a solar cell.

[0028] Specifically, solar cells are semiconductor devices that convert light into electrical energy using the photovoltaic effect. Solar cell technology has evolved from conventional aluminum back surface field (BSF) cells to passive emitter and rear cell (PERC) cells and then selective emitter (PERC+SE) cells. Compared to conventional BSF cells, PERC+SE cell technology adds a laser SE secondary diffusion process and a rear passivation process after the conventional diffusion process. The resulting rear passivation film is the main structural improvement of PERC solar cells over conventional cells. The principle is that the rear surface of the substrate is covered with a passivation film, which passivates the surface, improves long-wave response, and reduces surface complexation velocity, thereby improving the solar cell's photoelectric conversion efficiency.

[0029] In one embodiment, the present application provides a method for manufacturing a film. Referring to Figures 1 and 2, the method for manufacturing a film includes the following steps 102 to 104.

[0030] In step 102, a first passivation layer 204 is formed on a first surface of a substrate 202 using a first manufacturing process.

[0031] In step 104, a second manufacturing process is used to form a second passivation layer 206 on the surface of the first passivation layer 204 facing away from the substrate 202.

[0032] Here, the solar cell includes a substrate 202, which is used to receive incident light and generate photo-generated carriers.

[0033] For example, the solar cell may be a TOPCON (Tunnel Oxide Passivated Contact) cell, and both surfaces of the substrate 202 may be used to receive incident light. The substrate 202 is an N-type semiconductor substrate 202, i.e., N-type ions are doped into the substrate 202, and the N-type ions may be any of phosphorus, arsenic, or antimony. The substrate 202 has a first surface and an opposite second surface, and the second surface of the substrate 202 is an emitter, which may be a P-type doped layer, doped with P-type ions, and the emitter forms a PN junction with the base.

[0034] The first surface of the substrate 202 is formed with a tunnel layer and a doped polysilicon layer. The tunnel layer, together with the doped polysilicon layer, can constitute a passivation contact layer. The tunnel layer is used to achieve interface passivation of the first surface of the substrate 202 and achieves the effect of chemical passivation. Specifically, it saturates dangling bonds on the surface of the substrate 202 and reduces the interface defect state density on the first surface of the substrate 202, thereby reducing the number of complex centers on the basal first surface and slowing down the complex velocity of carriers. Here, the material of the tunnel layer is a dielectric material, which may be at least one of silicon dioxide, magnesium fluoride, amorphous silicon, polycrystalline silicon, silicon carbide, silicon nitride, silicon oxynitride, alumina, or titanium oxide. The first passivation layer 204 and the second passivation layer 206 can be used to form the tunnel layer. Here, the tunnel layer can bond with the dangling bonds on the first surface of the substrate 202, thereby suppressing carrier mixing on the surface of the solar cell and improving the photoelectric conversion efficiency of the solar cell.

[0035] In some embodiments, a passivation film is further provided on the side of the doped polysilicon layer away from the tunnel layer. The passivation film can increase the carrier concentration at the surface of the substrate 202, thereby suppressing carrier mixing and improving the open-circuit voltage, short-circuit current, and fill factor of the solar cell, thereby improving the photoelectric conversion efficiency on both sides. In some embodiments, the material of the passivation film can be one or more of silicon dioxide, alumina, silicon nitride, silicon oxynitride, or silicon carboxynitride. Therefore, in embodiments of the present application, the first passivation layer 204 and the second passivation layer 206 can be further used to form the passivation film.

[0036] In some embodiments, a passivation layer is also provided on the side of the emitter away from the substrate 202. The material of the passivation layer may be one or more of silicon dioxide, alumina, silicon nitride, silicon oxynitride, or silicon carbonate nitride. Therefore, in embodiments of the present application, the first passivation layer 204 and the second passivation layer 206 can be further utilized to form the passivation layer.

[0037] In the present embodiment, the material of the second passivation layer 206 is the same as the material of the first passivation layer 204. Specifically, during the semiconductor device manufacturing process, the characteristics of the materials of different layers are taken into consideration to prevent damage to already formed device structures during subsequent manufacturing processes. Because the present embodiment uses the first passivation layer 204 and the second passivation layer 206, which are made of a unified material, it is possible to more easily adapt the manufacturing process of other layers in the device by considering only the characteristics of the material of one passivation layer. Furthermore, the materials of the first passivation layer 204 and the second passivation layer 206 in the present embodiment can be reused from materials in related art, and correspondingly, the manufacturing processes of other layers do not need to be adaptively adjusted. This reduces the impact of the method of the present embodiment on the manufacturing process of other layers.

[0038] It can be further understood that even if the materials are the same, there are differences in the film formation effects of different manufacturing processes, i.e., the first passivation layer 204 and the second passivation layer 206 have different passivation effects. Specifically, in this embodiment, the passivation effect of the first passivation layer 204 is superior to that of the second passivation layer 206, so that the first passivation layer 204, which is closer to the substrate 202, can better passivate the substrate 202 and ensure device performance. Furthermore, because the passivation layer fabrication speed of the second manufacturing process is faster than that of the first manufacturing process, the second manufacturing process can be used to quickly supplement the total thickness of the passivation film (i.e., the sum of the thicknesses of the first passivation layer 204 and the second passivation layer 206) to a target thickness. The second passivation layer 206 can protect the first passivation layer 204, thereby preventing problems such as the first passivation layer 204 being too thin and therefore lacking in strength and being easily damaged, and the passivation film with the target thickness has sufficient reliability.

[0039] In this embodiment, the film manufacturing method can combine the advantages of the first manufacturing process and the second manufacturing process, and can effectively achieve both the overall passivation effect of the manufactured film and manufacturing efficiency.

[0040] In one embodiment, the first passivation layer 204 and the second passivation layer 206 are both made of alumina. Specifically, alumina can prevent unnecessary premature recombination of electrons and holes and can also serve as a mirror that reflects sunlight, allowing the sunlight to re-enter the active portion of the solar cell and be converted into electrical energy, thereby further improving the photoelectric conversion efficiency of the solar cell. In other embodiments, the first passivation layer 204 and the second passivation layer 206 may be other films made of the same material, and are not limited thereto.

[0041] In one embodiment, the first thickness of the first passivation layer 204 is smaller than the second thickness of the second passivation layer 206. For convenience of explanation, the sum of the first and second thicknesses is referred to as the target passivation thickness in this embodiment. Here, the first thickness can be understood as the thickness of the first passivation layer that can achieve a sufficient passivation effect on the substrate 202. After determining the first thickness, the second thickness can be determined based on the target passivation thickness and the first thickness. When the first passivation layer 204 having the first thickness and the second passivation layer 206 having the second thickness are formed, the solar cell has a first photoelectric conversion efficiency. When the passivation film having the target passivation thickness is formed entirely using the first manufacturing process, the solar cell has a second photoelectric conversion efficiency. Alternatively, the first photoelectric conversion efficiency and the second photoelectric conversion efficiency may be compared, and if the difference between the first photoelectric conversion efficiency and the second photoelectric conversion efficiency is smaller than a predetermined threshold, it may be determined that the current thicknesses of the first passivation layer 204 and the second passivation layer 206 are capable of achieving a sufficient passivation effect on the substrate 202. In this embodiment, because the passivation layer manufacturing speed of the first manufacturing process for manufacturing the first passivation layer 204 is relatively slow, providing the first passivation layer 204 with a small first thickness can effectively shorten the time required to manufacture the first passivation layer 204 using the first manufacturing process, thereby shortening the manufacturing time required to manufacture the entire film while ensuring the passivation effect.

[0042] In one embodiment, the first thickness of the first passivation layer 204 is 2 nm to 6 nm. For example, the first thickness may be any of 2 nm, 3 nm, 5 nm, and 6 nm, but is not limited to this embodiment. Correspondingly, the second thickness of the second passivation layer 206 can be adaptively adjusted according to the first thickness, so that the target passivation thickness can meet the device thickness requirements. Furthermore, an appropriate first thickness can be selected according to the device performance requirements. For example, assuming that the target passivation thickness is 25 nm, if the solar cell's photoelectric conversion efficiency requirements are low, a combination of a 2 nm first passivation layer 204 and a 23 nm second passivation layer 206 can be used. If the solar cell's photoelectric conversion efficiency requirements are high, a combination of a 6 nm first passivation layer 204 and a 19 nm second passivation layer 206 can be used. In this embodiment, by setting the first thickness of the first passivation layer 204 to any thickness between 2 nm and 6 nm, it is possible to better balance the overall manufacturing time of the film and the passivation effect of the manufactured film.

[0043] 3 , in one embodiment, when the first manufacturing process is used to form the first passivation layer 204 on the first surface of the substrate 202, the first passivation layer 204 is also formed on the peripheral surface of the substrate 202. The peripheral surface is connected to the first surface and parallel to the thickness direction of the substrate 202. Furthermore, when the second passivation layer 206 is formed, the second passivation layer 206 can extend to the side and cover the first passivation layer 204 located on the side surface of the substrate 202. In this embodiment, forming the first passivation layer 204 on the peripheral surface of the substrate 202 can further reduce the composite velocity on the side surface of the solar cell, thereby improving the photoelectric conversion efficiency of the solar cell.

[0044] In one embodiment, the first manufacturing process includes atomic layer deposition, i.e., forming the first passivation layer 204 on the first surface of the substrate 202 using an atomic layer deposition process. Here, atomic layer deposition (ALD) is a method of plating a material layer by layer in the form of a monolayer onto the first surface of the substrate 202. Specifically, during atomic layer deposition, the chemical reaction of each atomic layer is directly related to the previous layer, and this method deposits only one atom per reaction. Therefore, atomic layer deposition allows for precise control of the film thickness at the nanometer level and more easily produces high-quality films that are crack-free, dense, and maintain their shape. That is, when the first passivation layer 204 is formed using an atomic layer deposition process, the first passivation layer 204 can have a superior passivation effect. In this embodiment, atomic layer deposition is based on a self-limiting surface-limited reaction between volatile precursor molecules and a matrix, which can produce a first passivation layer 204 with a uniform film layer and excellent passivation effect, thereby ensuring the passivation effect of the first passivation layer 204 close to the first surface of the substrate 202.

[0045] In one embodiment, referring to FIG. 4, forming a first passivation layer 204 on a first surface of a substrate 202 using a first manufacturing process includes the following steps 402 to 408.

[0046] In step 402, a first precursor is introduced into a reaction chamber where a substrate 202 is located.

[0047] Here, the reaction chamber may be provided with multiple jet heads. Different jet heads are used to deliver different gaseous substances into the reaction chamber. The reaction chamber is provided with multiple corresponding jet regions, and the multiple jet heads are provided in a one-to-one correspondence with the multiple jet regions. Specifically, the transportable gaseous substances include, but are not limited to, precursors and inert gases. Preferably, the jet heads may be connected to the upper wall of the reaction chamber, and the gaseous substances are ejected perpendicularly to the first surface of the substrate 202, thereby ensuring that the first precursor is uniformly deposited on the first surface of the substrate 202. Furthermore, for example, if the material of the first passivation layer 204 is alumina, the first precursor may be an aluminum source, such as trimethylaluminum (TMA).

[0048] In step 404, after a first predetermined time has elapsed, the first precursor in the reaction chamber is evacuated and a second precursor is introduced.

[0049] Specifically, the second precursor is used to react with the first precursor to produce the first passivation layer 204. The second precursor may be sprayed through a spray head positioned above the substrate 202, thereby distinguishing it from the spray head spraying the first precursor. For example, if the material of the first passivation layer 204 is alumina, the second precursor may be an oxygen source, for example, including at least one of water and ozone. Specifically, by discharging the first precursor from the reaction chamber after the first predetermined time has elapsed, the remaining first precursor can be effectively prevented from reacting with the second precursor introduced thereafter. This effectively prevents unwanted reaction products from adhering to the first surface of the substrate 202, affecting the reaction on the first surface of the substrate 202, or causing uneven film formation on the first surface of the substrate 202. When the second precursor is introduced into the reaction chamber, the second precursor reacts with the first precursor already attached to the first surface of the substrate 202 to generate corresponding products to form the required atomic layer until the first precursor on the surface is completely consumed. Preferably, the first precursor in the reaction chamber can be evacuated by a vacuum pump, a molecular pump, or the like, but this embodiment is not limited thereto.

[0050] Furthermore, the first predetermined time is the period from the time when the jet head jets the first precursor to the time when the first precursor completely covers the first surface of the substrate 202. Therefore, the first predetermined time can be related to at least one of the area of ​​the first surface of the substrate 202, the volume of the reaction chamber, the jetting flow rate and / or jetting pressure of the first precursor, and the distance between the jet head and the substrate 202.

[0051] In step 406, after a second predetermined time has elapsed, the second precursor in the reaction chamber is evacuated.

[0052] Similar to step 404, the second predetermined time is the period from when the jet head jets the second precursor to when the second precursor reaches the substrate 202 and covers the first surface of the substrate 202. Therefore, the second predetermined time can be related to at least one of the area of ​​the first surface of the substrate 202, the volume of the reaction chamber, the jetting flow rate and / or jetting pressure of the second precursor, and the distance between the jet head and the substrate 202, etc.

[0053] In step 408, the above steps 402 to 406 are repeatedly performed until the thickness of the first passivation layer 204 reaches the first thickness.

[0054] Specifically, the number of times steps 402 to 406 are repeated can be determined based on the thickness of the monolayer atomic layer and the first thickness of the first passivation layer 204. For example, steps 402 to 406 can be repeated 20 to 50 times to form the first passivation layer 204 having the first thickness.

[0055] In this embodiment, all of the first precursor that did not adhere to the first surface of the substrate 202 was removed before the second precursor was introduced, so that when the second precursor was introduced, no reaction products of the first precursor and the second precursor were produced outside the first surface of the substrate 202. This achieved "temporal" isolation of the first precursor and the second precursor, allowing a large proportion of the first precursor and the second precursor to react with the first surface of the substrate 202, and the first precursor and the second precursor to react on the first surface of the substrate 202 in a strict self-regulating manner, ultimately forming a first passivation layer 204 that is uniform and has excellent passivation effect.

[0056] In one embodiment, referring to FIG. 5, forming a first passivation layer 204 on a first surface of a substrate 202 using a first manufacturing process includes the following steps 502 to 504.

[0057] In step 502, the substrate 202 is controlled to move and pass through a first jet region for introducing a first precursor, a second jet region for introducing an isolation gas, and a third jet region for introducing a second precursor, in order.

[0058] Here, the second precursor is used to react with the first precursor to produce the first passivation layer 204. The isolation gas does not react with the first precursor and the second precursor. The isolation gas is used to separate and prevent the first precursor and the second precursor from reacting with regions other than the substrate surface. Specifically, the isolation gas prevents the gaseous first precursor and the second precursor from chemical vapor deposition before reaching the substrate, ensuring that the reaction between the first precursor and the second precursor results in atomic layer deposition on the substrate surface, thereby improving the film formation quality of the first passivation layer 204. The isolation gas may be nitrogen gas (N2) or an inert gas. Specifically, as shown in FIG. 6, the first precursor, the isolation gas, and the second precursor are introduced through different jet heads, i.e., the first jet head is for jetting the first precursor, the second jet head is for jetting the isolation gas, and the third jet head is for jetting the second precursor. The plurality of jet heads are provided in one-to-one correspondence with the plurality of jet regions, and the different jet heads can be linearly arranged on the upper wall of the reaction chamber. Preferably, the substrate 202 can be placed on a hot plate, and the movement of the hot plate can be controlled to drive the substrate 202 through each jet region in turn, thereby facilitating the heat treatment of the substrate 202.

[0059] Furthermore, the movement speed of the substrate 202 can be determined by the jet flow rate and / or jet pressure of each jet head, thereby ensuring the atomic layer deposition effect. As can be seen, the atomic layer deposition effect, the adsorption effect of the first precursor, the reaction effect of the second precursor, and the isolation effect of the isolation gas are all related to each other. Therefore, based on the requirements for the atomic layer deposition effect, the movement speed of the substrate 202, the jet flow rate and / or jet pressure of each jet head, and the control logic of each jet head can be appropriately adjusted. For example, each jet head can continuously deliver a corresponding gaseous substance into the reaction chamber, thereby simplifying the control logic of the jet head and optimizing the adsorption effect of the first precursor, the reaction effect of the second precursor, and the isolation effect of the isolation gas. For example, each jet head can begin delivering a corresponding gaseous substance into the reaction chamber only immediately before the substrate 202 enters the corresponding jet region, thereby reducing the consumption of each material. Furthermore, for example, the corresponding jet head of the precursor may be controlled to start transporting the corresponding precursor into the reaction chamber only just before the substrate 202 enters the corresponding jet area, and the jet head of the isolation gas may be controlled to continuously transport the isolation gas into the reaction chamber, thereby reducing the amount of precursor used while ensuring the isolation effect and reaction effect.

[0060] In step 504, the above step 502 is repeatedly performed until the thickness of the first passivation layer 204 reaches the first thickness.

[0061] For example, multiple sets of jet heads may be sequentially arranged within the reaction chamber. As shown in FIG. 7, two sets of jet heads are shown, each set including a first jet head, a second jet head, and a third jet head. That is, the reaction chamber is sequentially arranged with the first jet head, the second jet head, the third jet head, and so on, and the substrate 202 is controlled to move linearly through each jet area in turn. While this requires a large-volume reaction chamber, it can achieve high-speed processing of the substrate 202. Furthermore, by arranging each substrate 202 under a different set of jet heads, multiple substrates 202 can be processed synchronously. This significantly improves the manufacturing efficiency of the first passivation layer 204. 6, only one set of jet heads may be provided in the reaction chamber, and after one cycle of reaction is completed, all gases in the reaction chamber are exhausted, and the substrate 202 is moved back to the first jet area, and the above steps are repeated. This example has lower production efficiency than the previous example, but is more suitable for scenarios where the volume requirement for the reaction chamber is low and production volume is low.

[0062] 4 , in which the first and second precursors are separated in time by an evacuation process, in this embodiment, the substrate 202 is controlled to move through the first, second, and third jet regions in sequence, thereby achieving separation in space. This eliminates the need for an evacuation process for the reaction chamber and significantly reduces the time required to form the first passivation layer 204. The provision of the second jet region actively separates the first and second precursors, and the width of the second jet region, the jet flow rate of the separation gas, and / or the jet pressure are appropriately set to effectively separate the first and second precursors, so that a large portion of the reaction between the first and second precursors occurs on the first surface of the substrate 202. This effectively improves the uniformity of the first passivation layer 204 and further enhances the passivation effect of the first passivation layer 204. Furthermore, the substrate 202 can be continuously moved while being placed on a hot plate. The technical solution of this embodiment is less susceptible to wraparound when forming the first passivation layer 204, which can result in an uneven film layer being formed on the back surface of the substrate 202, affecting the appearance and photoelectric conversion performance of the solar cell. Therefore, this embodiment further effectively suppresses the above problem, thereby providing a solar cell with good overall performance.

[0063] In one embodiment, referring to FIG. 8, forming a first passivation layer 204 on a first surface of a substrate 202 using a first manufacturing process includes the following steps 802 to 804.

[0064] In step 802, the substrate 202 is controlled to move through a first jet region for introducing a first precursor, an exhaust region, and a third jet region for introducing a second precursor, in order. The exhaust region is used to exhaust gases in the exhaust region from the reaction chamber.

[0065] The second precursor is used to react with the first precursor to produce the first passivation layer 204. Specifically, as shown in FIG. 9 , the first precursor and the second precursor are introduced through different jet heads, i.e., the first jet head is for jetting the first precursor, and the third jet head is for jetting the second precursor. In this embodiment, an exhaust pipe is further provided between the first jet head and the third jet head, and the exhaust pipe may be connected to a vacuum pump, thereby suctioning the gaseous material in the exhaust region. It should be understood that the specific configuration of the first and third jet regions can be seen in the embodiment shown in FIG. 5 and will not be repeated here. By providing the exhaust region, if the first precursor or the second precursor spreads in the exhaust region, it can be immediately exhausted from the reaction chamber, suppressing the reaction between the first precursor and the second precursor and improving the quality of the first passivation layer 204.

[0066] In step 804, the above step 802 is repeatedly performed until the thickness of the first passivation layer 204 reaches the first thickness.

[0067] In this embodiment, the substrate 202 is controlled to move sequentially through the first jet region, the exhaust region, and the third jet region, thereby achieving spatial isolation and eliminating the need to exhaust the entire reaction chamber, significantly shortening the time required to form the first passivation layer 204. The exhaust region separates the first precursor from the second precursor, and the width of the exhaust region is rationally set to effectively separate the first precursor from the second precursor, ensuring that a large portion of the reaction between the first precursor and the second precursor occurs on the first surface of the substrate 202. This effectively improves the uniformity of the first passivation layer 204 and the passivation effect of the first passivation layer 204. Furthermore, because the substrate 202 is placed on a hot plate and can be continuously moved, the technical solution of this embodiment is less susceptible to wraparound during the formation of the first passivation layer 204. This wraparound phenomenon can result in an uneven film layer being formed on the back surface of the substrate 202, which can affect the appearance and photovoltaic performance of the solar cell. Therefore, this embodiment further effectively suppresses the above problems, thereby providing a solar cell with good overall performance.

[0068] In one embodiment, the substrate 202 can be controlled to move sequentially through a first jet region of the first precursor, a second jet region of the isolation gas, an exhaust region, and a third jet region of the second precursor, or the substrate 202 can be controlled to move sequentially through a first jet region of the first precursor, an exhaust region, a second jet region of the isolation gas, and a third jet region of the second precursor. It can be understood that the specific arrangements of the first jet region, the second jet region, the exhaust region, and the third jet region in this embodiment can be referred to in the previous embodiments and will not be repeated here.

[0069] In one embodiment, referring to FIG. 10, forming a first passivation layer 204 on a first surface of a substrate 202 using a first manufacturing process includes the following steps 1002 to 1004.

[0070] In step 1002, the substrate 202 is controlled to move and pass through a first spout region into which a first precursor is introduced and a third spout region into which a second precursor is introduced in sequence.

[0071] The second precursor is used to react with the first precursor to produce the first passivation layer 204. Specifically, referring to FIG. 11 , the first precursor and the second precursor are introduced through different jet heads, i.e., the first jet head is for jetting the first precursor, and the third jet head is for jetting the second precursor. A distance d is provided between the first jet region and the third jet region. Specifically, increasing the distance between the first jet region and the third jet region effectively suppresses the reaction of the first precursor and the second precursor in regions other than the substrate 202, thereby effectively suppressing problems such as unwanted reaction products adhering to the first surface of the substrate 202, affecting the reaction on the first surface of the substrate 202, or causing uneven film formation on one side of the substrate 202. Furthermore, the distance d is determined by the jet flow rates and / or jet pressures of the first precursor and the second precursor. Specifically, the purpose of providing the distance d is to reduce the reaction of the first precursor and the second precursor outside the substrate 202 and improve the passivation effect of the first passivation layer 204. As can be seen, the greater the jetting flow rate or jetting pressure of the first precursor and the second precursor, the more likely the two precursors are to react under the action of the airflow. Therefore, the setting of the distance d has a positive correlation with the jetting flow rate and jetting pressure of the first precursor and the second precursor. That is, the greater the jetting flow rate and / or jetting pressure of the first precursor and the second precursor, the greater the distance d required, thereby improving the spatial isolation effect. As can be seen, in this embodiment, the first jetting region and the third jetting region do not need to be provided with a jetting region for introducing other gases.

[0072] In step 1004, the above step 1002 is repeatedly performed until the thickness of the first passivation layer 204 reaches the first thickness.

[0073] In this embodiment, the first and third jet regions are separated by a distance d, eliminating the need for additional equipment or gases. That is, a large portion of the first precursor and the second precursor react on the first surface of the substrate 202, significantly simplifying the structure of the reaction chamber while ensuring uniformity and passivation effectiveness of the first passivation layer 204. Furthermore, because the substrate 202 is mounted on a hot plate and can be continuously moved, the technical solution of this embodiment is less susceptible to wraparound during the formation of the first passivation layer 204. This wraparound can result in an uneven film layer being formed on the back surface of the substrate 202, which can adversely affect the appearance and photoelectric conversion performance of the solar cell. Therefore, this embodiment effectively prevents the above problems and provides a solar cell with excellent overall performance.

[0074] In one embodiment, the second manufacturing process includes plasma-enhanced chemical vapor deposition (PECVD), i.e., the second passivation layer 206 can be formed on the surface of the first passivation layer 204 facing away from the substrate 202. Plasma-enhanced chemical vapor deposition (PECVD) is a film manufacturing method that utilizes a discharge phenomenon to ionize atoms corresponding to a target material, followed by chemical reaction deposition on the substrate. As can be seen, atomic layer deposition is limited by a reaction mechanism that can only form one layer of atoms at a time. The time required for the atomic layer deposition process is long, resulting in low production capacity per unit time. Compared to atomic layer deposition, plasma-enhanced chemical vapor deposition does not require a first precursor and a second precursor; it only reacts on the surface of the substrate 202. The first precursor does not need to completely adhere to the first surface of the substrate 202. By using a process that involves discharging the first precursor from the reaction chamber and introducing the second precursor, the manufacturing efficiency of a passivation layer of the same material can be significantly improved. However, because the film formation uniformity of plasma-enhanced chemical vapor deposition is inferior to that of atomic layer deposition, and the ionization process causes impact damage to the passivation surface, it is difficult to achieve optimal passivation effect using plasma-enhanced chemical vapor deposition alone. In this embodiment, the second passivation layer 206 can be produced more quickly by using plasma-enhanced chemical vapor deposition, and the passivation effect on the substrate 202 can be greatly improved by combining atomic layer deposition and plasma-enhanced chemical vapor deposition.

[0075] In one embodiment, the second manufacturing process includes alternating plasma-enhanced chemical vapor deposition and atomic layer deposition. In this embodiment, the second manufacturing process employs alternating plasma-enhanced chemical vapor deposition and atomic layer deposition. Because the film manufacturing rate by plasma-enhanced chemical vapor deposition is greater than the film manufacturing rate by atomic layer deposition, the second manufacturing process employs alternating plasma-enhanced chemical vapor deposition and atomic layer deposition, thereby achieving a film manufacturing rate that is faster than the film manufacturing rate by the first manufacturing process, further improving the overall efficiency of film manufacturing.

[0076] In one embodiment, the hydrogen content of the first passivation layer 204 is lower than the hydrogen content of the second passivation layer 206. The hydrogen content of the passivation layer is also related to the corresponding manufacturing process. Specifically, for example, if the materials of the first passivation layer 204 and the second passivation layer 206 are alumina, the hydrogen content of the alumina produced using plasma-enhanced chemical vapor deposition (PCVD) is highest, the alumina film produced using the atomic layer deposition "time" method (e.g., the embodiment shown in FIG. 4) is inferior, and the hydrogen content of the alumina produced using the atomic layer deposition "space" method (e.g., the embodiment shown in FIG. 5) is lowest. The lower the hydrogen atom content in the passivation layer, the better the passivation effect. Therefore, measuring the hydrogen content of the first passivation layer 204 and the second passivation layer 206 can effectively determine the manufacturing process and obtain the passivation effect of each passivation layer.

[0077] In one embodiment, the negative charge density of the first passivation layer 204 is greater than the negative charge density of the second passivation layer 206. Specifically, the higher the negative charge density at the interface between the passivation layer and the substrate 202 (e.g., a silicon chip), the stronger the ability to shield minority carriers from the p-type silicon surface, resulting in better field passivation characteristics. In this embodiment, by making the negative charge density of the first passivation layer 204 greater than the negative charge density of the second passivation layer 206, the passivation effect of the first passivation layer 204 closer to the first surface of the substrate 202 is superior to the passivation effect of the second passivation layer 206 further away from the substrate 202, thereby more effectively improving the photoelectric conversion efficiency of the solar cell. Therefore, the passivation effect of each passivation layer can be determined by measuring the negative charge densities of the first passivation layer 204 and the second passivation layer 206.

[0078] Although the steps shown in the flowcharts according to the above embodiments are shown in the order indicated by the arrows, it should be understood that these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps may be performed in other orders. Furthermore, at least some of the steps shown in the flowcharts according to the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily performed and completed at the same time, but may be performed at different times. The order in which these steps or stages are performed is also not necessarily performed in order, and they may be performed alternately or interleaved with other steps or at least some of the steps or stages in other steps.

[0079] In one embodiment, still referring to FIG. 2 , the present application further provides a solar cell, the solar cell including a substrate 202, a first passivation layer 204, and a second passivation layer 206. The substrate 202 is adapted to receive incident light and generate photo-generated carriers. For example, in some embodiments, the solar cell is a bifacial cell, i.e., both surfaces of the substrate 202 are adapted to receive solar light. The substrate 202 may be a silicon substrate. Materials for the silicon substrate may include monocrystalline silicon, polycrystalline silicon, amorphous silicon, and microcrystalline silicon. The first passivation layer 204 is disposed on the first surface of the substrate 202. The second passivation layer 206 is disposed on the surface of the first passivation layer 204 facing away from the substrate 202. The material of the second passivation layer 206 is the same as the material of the first passivation layer 204.

[0080] In one embodiment, the hydrogen content of the first passivation layer 204 is less than the hydrogen content of the second passivation layer 206 and / or the negative charge density of the first passivation layer 204 is greater than the negative charge density of the second passivation layer 206.

[0081] In one embodiment, the first thickness of the first passivation layer 204 is less than the second thickness of the second passivation layer 206 .

[0082] In one embodiment, the first thickness of the first passivation layer 204 is between 2 nm and 6 nm.

[0083] In one embodiment, the material of the first passivation layer 204 and the material of the second passivation layer 206 are both alumina.

[0084] 3 , in one embodiment, the present application further provides a solar cell, in which a first passivation layer 204 of the solar cell extends to a peripheral surface of a substrate 202, the peripheral surface being connected to the first surface and parallel to a thickness direction of the substrate 202. A second passivation layer 206 extends to and covers the first passivation layer 204 located on the peripheral surface of the substrate 202.

[0085] In one embodiment, the first passivation layer 204 and the second passivation layer 206 in the solar cell are formed by using the film manufacturing method according to any of the above embodiments. Based on the above-described film manufacturing method, this embodiment provides a solar cell with a fast manufacturing speed and good performance. Correspondingly, an embodiment of the present application further provides a solar cell module, the solar cell module including a cell string, the cell string being connected to the solar cell provided by any of the above embodiments or the solar cell manufactured by using the film manufacturing method according to any of the above embodiments.

[0086] The photovoltaic module further includes an encapsulation layer and a cover plate. The encapsulation layer is used to cover the surface of the battery string. The cover plate is used to cover the surface of the encapsulation layer away from the battery string. The solar cells are electrically connected in the form of a single cell or a multi-cell to form multiple battery strings. The multiple battery strings are electrically connected in series and / or parallel. Specifically, in some embodiments, the multiple battery strings are electrically connected by conductive strips. The encapsulation layer covers the surface of the solar cells. Exemplarily, the encapsulation layer may be an organic encapsulation film such as an ethylene-vinyl acetate copolymer film, a polyethylene octene copolymer film, or a polyethylene terephthalate film. The cover plate may be a light-transmitting cover plate such as a glass cover plate or a plastic cover plate.

[0087] An embodiment of the present application further provides a solar power generation system including the solar power generation module according to any one of the above embodiments.

[0088] As can be understood, a solar power generation system can be applied to a solar power generation station, such as a ground power generation station, a rooftop power generation station, or a water-based power generation station, and can also be applied to equipment or devices that generate electricity using solar energy, such as a user's solar energy power supply, a solar energy street lamp, a solar energy vehicle, or a solar energy building. Of course, as can be understood, the application scenarios of a solar power generation system are not limited to these. That is, a solar power generation system can be applied to any field that requires power generation using solar energy. Taking a solar power generation system network as an example, the solar power generation system can include a solar power generation array, a collector box, and an inverter. A solar power generation array can be a combination of an array of multiple solar power generation modules. For example, multiple solar power generation modules can form multiple solar power generation arrays. The solar power generation array is connected to the collector box, which can collect the current generated by the solar power generation array. The collected current flows through an inverter to be converted into AC power required by the utility grid, and then connected to the utility grid to realize solar power supply.

[0089] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, unless there is a contradiction in the combination of these technical features, they should all be considered within the scope described in this specification.

[0090] The above examples merely represent some embodiments of the present application, and although the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the claims of the present application. It should be noted that those skilled in the art may make minor modifications and improvements without departing from the concept of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present application is determined by the scope of the accompanying claims.

Claims

1. A method for producing a film, comprising: forming a first passivation layer on one surface of a substrate using a first manufacturing process; forming a second passivation layer on a surface of the first passivation layer away from the substrate using a second manufacturing process, the material of the second passivation layer being the same as the material of the first passivation layer; forming a first passivation layer on one surface of a substrate using the first manufacturing process; The substrate is controlled to move and pass through a first jet region of a first precursor, an exhaust region, and a third jet region of a second precursor in this order, and the second precursor reacts with the first precursor to generate the first passivation layer; repeating the above until the thickness of the first passivation layer reaches a first thickness, the first thickness of the first passivation layer being smaller than the second thickness of the second passivation layer, and the first thickness of the first passivation layer being between 2 nm and 6 nm; the first manufacturing process includes atomic layer deposition, a manufacturing rate of the first manufacturing process is lower than a manufacturing rate of the second manufacturing process, and a passivation effect of the first passivation layer is better than a passivation effect of the second passivation layer; The first passivation layer is further formed on a peripheral surface of the substrate; the second passivation layer extends to a peripheral surface of the substrate and covers the first passivation layer located on the peripheral surface of the substrate; the hydrogen content of the first passivation layer is less than the hydrogen content of the second passivation layer; A method for producing a film, wherein the negative charge density of the first passivation layer is greater than the negative charge density of the second passivation layer.

2. The method of claim 1 , wherein the second manufacturing process comprises plasma enhanced chemical vapor deposition or alternating plasma enhanced chemical vapor deposition and atomic layer deposition.

3. 3. The method for manufacturing a film according to claim 1, wherein the first passivation layer and the second passivation layer are both made of alumina.

4. A solar cell, A solar cell comprising a substrate, and a first passivation layer and a second passivation layer formed by the method for producing a film according to claim 1 or 2.

5. A solar cell, A solar cell comprising a substrate and a first passivation layer and a second passivation layer formed by the film manufacturing method according to claim 3.

6. A solar cell, A substrate; a first passivation layer provided on one surface of the substrate; a second passivation layer provided on a surface of the first passivation layer away from the substrate; the material of the second passivation layer is the same as the material of the first passivation layer; the hydrogen content of the first passivation layer is less than the hydrogen content of the second passivation layer; a negative charge density of the first passivation layer is greater than a negative charge density of the second passivation layer; The first passivation layer comprises: The substrate is controlled to move and pass through a first jet region of a first precursor, an exhaust region, and a third jet region of a second precursor in this order, and the second precursor reacts with the first precursor to generate the first passivation layer; and repeating the above until the thickness of the first passivation layer reaches a first thickness. formed on one surface of a substrate using a first manufacturing process and also provided on a peripheral surface of the substrate; The solar cell, wherein the second passivation layer extends to the peripheral surface of the substrate and covers the first passivation layer located on the peripheral surface of the substrate.

7. 7. The solar cell of claim 6, wherein the first thickness of the first passivation layer is less than the second thickness of the second passivation layer.

8. 8. The solar cell according to claim 7, wherein the first thickness of the first passivation layer is 2 nm to 6 nm.

9. 9. The solar cell according to claim 6, wherein the first passivation layer and the second passivation layer are both made of alumina.

10. A photovoltaic module, including a battery string, A photovoltaic power generation module, characterized in that the battery string is formed by connecting a plurality of solar cells according to any one of claims 6 to 8.

11. A photovoltaic module, including a battery string, 10. A photovoltaic power generation module, wherein the battery string is formed by connecting a plurality of solar cells according to claim 9.

12. A solar power generation system, A photovoltaic power generation system comprising the photovoltaic power generation module according to claim 10.

13. A solar power generation system, A photovoltaic power generation system comprising the photovoltaic power generation module according to claim 11.

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