Photovoltaic cell, photovoltaic module, photovoltaic system and electric equipment

Abstract

The embodiment of the invention provides a photovoltaic cell, a photovoltaic module, a photovoltaic system and electric equipment. The photovoltaic cell comprises a substrate; the passivation anti-reflection layer is arranged on at least one side of the substrate in the thickness direction, the passivation anti-reflection layer comprises at least one dielectric layer and at least one hydrogen fixing layer, the dielectric layer and the hydrogen fixing layer are arranged in a stacked mode, and the lattice gap of the hydrogen fixing layer is smaller than or equal to 0.074 nm. In the photovoltaic cell, the passivation anti-reflection layer can effectively improve the problem of hydrogen dissipation in the high-temperature preparation process.

Description

Technical Field

[0001] This application relates to the field of photovoltaic cell technology, and in particular to a photovoltaic cell, photovoltaic module, photovoltaic system and electrical equipment. Background Technology

[0002] Photovoltaic cells, as a core technology for clean energy, are widely used in distributed photovoltaic power stations, building-integrated photovoltaics (BIPV), mobile power supplies, and aerospace. Back contact (BC) cells and tunnel oxide passivated contact (TOPCon) cells have become the mainstream direction of photovoltaic technology due to their high conversion efficiency, low metal shading rate, and excellent temperature coefficient performance.

[0003] However, during the high-temperature fabrication process of these two types of batteries, the passivation antireflection film generally suffers from hydrogen (H) escaping. The presence of hydrogen in the passivation film plays a crucial role in the passivation effect on silicon substrate surface defects. However, in existing technologies, due to improper selection of film materials and unreasonable structural design, a large amount of hydrogen escapes during high-temperature sintering and metallization processes, leading to problems such as decreased passivation performance, enhanced metal-semiconductor interface recombination, and accelerated PID attenuation. Summary of the Invention

[0004] This application provides a photovoltaic cell, a photovoltaic module, a photovoltaic system, and an electrical device to address the shortcomings of related technologies.

[0005] In a first aspect, this application provides a photovoltaic cell, which includes:

[0006] Substrate;

[0007] At least one passivation antireflection layer is disposed on at least one side of the substrate in the thickness direction. The passivation antireflection layer includes at least one dielectric layer and at least one hydrogen solidification layer. At least one dielectric layer and at least one hydrogen solidification layer are stacked. At least one dielectric layer is disposed close to the substrate relative to at least one hydrogen solidification layer. The lattice gap of the hydrogen solidification layer is less than or equal to 0.074 nm.

[0008] In one possible implementation, the hydrogen-fixing layer comprises at least one of silicon oxide, aluminum oxide, silicon nitride, and silicon oxynitride.

[0009] In one possible implementation, the passivation antireflection layer comprises at least two dielectric layers, with at least two dielectric layers and at least one hydrogen solidification layer alternately stacked;

[0010] The at least two dielectric layers include a first dielectric layer and a second dielectric layer, wherein the first dielectric layer is disposed close to the substrate relative to the second dielectric layer, and the refractive index of the first dielectric layer is greater than the refractive index of the second dielectric layer.

[0011] In one possible implementation, the dielectric layer further includes a third dielectric layer, with the second dielectric layer located between the first dielectric layer and the third dielectric layer, and the refractive index of the second dielectric layer being greater than that of the third dielectric layer.

[0012] In one possible implementation, the hydrogen fixation layer includes a first hydrogen fixation layer, a second hydrogen fixation layer, and a third hydrogen fixation layer, wherein the first dielectric layer, the first hydrogen fixation layer, the second dielectric layer, the second hydrogen fixation layer, the third dielectric layer, and the third hydrogen fixation layer are stacked sequentially.

[0013] In one possible implementation, the photovoltaic cell further includes a metal electrode located on at least one side of the substrate in the thickness direction, and the metal electrode extends through at least one opposite side of the passivation antireflection layer.

[0014] In one possible implementation, at least one of the passivation antireflection layers further includes a hydrogen release layer that extends through all of the dielectric layers and all of the hydrogen fixation layers, and the hydrogen release layer is located on opposite sides of the metal electrode.

[0015] In one possible implementation, the photovoltaic cell further includes: a tunneling oxide layer and a first passivation layer, wherein the first passivation layer and the tunneling oxide layer are disposed on opposite sides of the substrate in the thickness direction;

[0016] There are two passivation and antireflection layers. One passivation and antireflection layer is disposed on the side of the first passivation layer away from the substrate, and the other passivation and antireflection layer is disposed on the side of the tunneling oxide layer away from the substrate.

[0017] In one possible implementation, the photovoltaic cell further includes: a first doped layer located between the tunneling oxide layer and the passivation antireflection layer;

[0018] Alternatively, it may include a second doped layer and an emitter, wherein the second doped layer is located between the tunneling oxide layer and the passivation antireflection layer, and the emitter is located between the substrate and the first passivation layer.

[0019] Secondly, this application provides a photovoltaic module, including: the photovoltaic cell provided in the first aspect above.

[0020] Thirdly, this application provides a photovoltaic system, including: the photovoltaic cell provided in the first aspect or the photovoltaic module provided in the second aspect.

[0021] Thirdly, this application provides an electrical device, including: the photovoltaic cell provided in the first aspect or the photovoltaic module provided in the second aspect.

[0022] The photovoltaic cell, photovoltaic module, photovoltaic system, and electrical equipment provided in this application include a photovoltaic cell comprising a substrate and a passivation and antireflection layer. The passivation and antireflection layer comprises a dielectric layer and a hydrogen fixation layer, with the spacing between the hydrogen fixation layers being less than or equal to 0.074 nm. By setting the substrate to support the passivation and antireflection layer and to absorb sunlight and generate charge carriers, by setting the dielectric layer to adjust the optical properties of the photovoltaic cell such as the refractive index, and by setting the lattice spacing of the hydrogen fixation layer within 0.074 nm, the physical barrier or chemical adsorption of the hydrogen fixation layer during high-temperature fabrication can be used to suppress the outward escape of hydrogen atoms. During metal ablation, the hydrogen fixation layer can release hydrogen atoms to improve the passivation effect, thereby improving the passivation effect of the metal-semiconductor interface region. The stacked structure of the dielectric layer and the hydrogen fixation layer forms an interface barrier, which can reduce the path of hydrogen outward escape. The dielectric layer and the hydrogen fixation layer work together to maintain a high hydrogen retention rate during high-temperature processes, solving problems such as interface defect regeneration and passivation performance degradation caused by hydrogen escape, thereby improving the performance of the photovoltaic cell.

[0023] In addition to the technical problems solved by the embodiments of this application, the technical features constituting the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions described above, other technical problems that can be solved by the photovoltaic cells, photovoltaic modules, photovoltaic systems, and electrical equipment provided by this application, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further described in detail in the specific embodiments. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of a photovoltaic cell provided in an embodiment of this application;

[0026] Figure 2 This is another structural schematic diagram of a photovoltaic cell provided in an embodiment of this application;

[0027] Figure 3 This is yet another structural schematic diagram of a photovoltaic cell provided in an embodiment of this application;

[0028] Figure 4 This is another structural schematic diagram of the photovoltaic cell provided in the embodiments of this application.

[0029] Explanation of reference numerals in the attached figures:

[0030] 100 - Substrate; 200 - Passivation and antireflection layer; 210 - Dielectric layer; 211 - First dielectric layer; 212 - Second dielectric layer; 213 - Third dielectric layer; 220 - Hydrogen fixation layer; 221 - First hydrogen fixation layer; 222 - Second hydrogen fixation layer; 223 - Third hydrogen fixation layer; 230 - Hydrogen release layer; 300 - Metal electrode; 310 - First metal electrode; 320 - Second metal electrode; 400 - Tunneling oxide layer; 500 - First passivation layer; 600 - First doped layer; 610 - First sub-doped layer; 620 - Second sub-doped layer; 700 - Second doped layer; 800 - Emitter; 900 - Second passivation layer. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0032] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0033] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0034] The terms "first," "second," and "third" (if any) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein.

[0035] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or display that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or display.

[0036] In related technologies, both back contact (BC) and tunnel oxide passivated contact (TOPCon) batteries commonly suffer from hydrogen (H) escaping during high-temperature fabrication of their passivation antireflection films. The presence of hydrogen in the passivation film plays a crucial role in the passivation effect on silicon substrate surface defects. However, in existing technologies, improper selection of film materials and unreasonable structural design lead to significant hydrogen escaping during high-temperature sintering and metallization processes, resulting in decreased passivation performance, enhanced metal-semiconductor interface recombination, and accelerated PID degradation.

[0037] In view of the above problems, embodiments of this application provide a photovoltaic cell, a photovoltaic module, a photovoltaic system, and an electrical device. The photovoltaic cell improves the performance of the photovoltaic cell by setting a passivation and antireflection layer composed of a dielectric layer and a hydrogen fixation layer, and controlling the lattice gap of the hydrogen fixation layer to within 0.074 nm, so as to significantly reduce the hydrogen escape rate through the physical barrier or chemical adsorption effect of the hydrogen fixation layer.

[0038] The following detailed description, in conjunction with the accompanying drawings, illustrates the specific implementation methods of the photovoltaic cells, photovoltaic modules, photovoltaic systems, and electrical equipment provided in this application.

[0039] Reference Figures 1 to 4 As shown, this application embodiment provides a photovoltaic cell, which includes a substrate 100 and at least one passivation antireflection layer 200. The passivation antireflection layer 200 is disposed on at least one side in the thickness direction of the substrate 100. The passivation antireflection layer 200 includes at least one dielectric layer 210 and at least one hydrogen solidification layer 220. The dielectric layer 210 and the hydrogen solidification layer 220 are stacked, and the lattice gap of the hydrogen solidification layer 220 is less than or equal to 0.074 nm.

[0040] The photovoltaic cell in this embodiment is a semiconductor device that can convert light energy into electrical energy, including TOPCon cells, BC cells, etc. The substrate 100 refers to the basic functional structure of the photovoltaic cell, which can absorb sunlight and generate charge carriers. The substrate 100 is used to support other functional layers such as the passivation antireflection layer 200. The substrate 100 can be a monocrystalline silicon substrate 100, a polycrystalline silicon substrate 100, or an amorphous silicon substrate 100, etc. This embodiment does not limit this.

[0041] The passivation and antireflection layer 200 refers to a film structure that simultaneously possesses surface passivation and antireflection functions. The passivation and antireflection layer 200 is used to reduce light reflection and suppress surface defects. Among them, the dielectric layer 210 can be used to adjust the optical performance of photovoltaic cells and serves as a support for the hydrogen fixation layer 220. The hydrogen fixation layer 220 can be used to suppress hydrogen escape, thereby alleviating problems such as decreased passivation performance, enhanced metal-semiconductor interface recombination, and aggravated PID degradation caused by hydrogen escape.

[0042] In specific implementation, the dielectric layer 210 and the hydrogen solidification layer 220 are stacked and arranged adjacently. The dielectric layer 210 and the hydrogen solidification layer 220 can each be a single layer, or the dielectric layer 210 and the hydrogen solidification layer 220 can each be multiple layers. The multiple dielectric layers 210 and the multiple hydrogen solidification layers 220 are stacked alternately. In this way, the density of the passivation and antireflection layer 200 can be improved by the alternating stacking structure of the dielectric layer 210 and the hydrogen solidification layer 220, so as to achieve interface barrier and reduce the hydrogen escape path. Thus, the passivation and antireflection layer 200 can effectively suppress hydrogen escape during the high-temperature preparation process through the synergistic effect of material properties and structural design.

[0043] Specifically, the hydrogen-fixed layer 220 comprises a crystal structure, in which the spacing between adjacent atoms is called the lattice interstices. In this embodiment, the lattice interstices of the hydrogen-fixed layer 220 are less than or equal to 0.074 nm. Since the diameter of a hydrogen atom is approximately 0.074 nm, when the lattice interstices of the hydrogen-fixed layer 220 are less than or equal to 0.074 nm, hydrogen atoms cannot escape through the lattice interstices of the hydrogen-fixed layer 220. The lattice interstices have a physical barrier effect on hydrogen atoms. Thus, when the hydrogen-fixed layer 220 is sintered at high temperature, it can effectively prevent hydrogen atoms from escaping outward. Suppressing hydrogen escaping outward can enhance the passivation effect on surface defects of the silicon substrate 100, reduce interface defects, and thereby reduce the carrier recombination rate at the metal-semiconductor interface.

[0044] Furthermore, the reduction in hydrogen escape also lowers the potential difference of the passivation antireflection layer 200, preventing the triggering of the PID effect and improving the stability of the photovoltaic cell under high temperature and high humidity conditions. During metal ablation, the damaged hydrogen solidification layer 220 can release a large number of hydrogen atoms, thereby effectively passivating the metal-semiconductor interface region and improving the photoelectric conversion efficiency of the photovoltaic cell.

[0045] Furthermore, the hydrogen-fixing layer 220 can also chemically adsorb hydrogen atoms. For example, when the hydrogen-fixing layer 220 contains Si-N and Si-O bonds, the polarity of the Si-N and Si-O bonds can chemically adsorb hydrogen atoms, with a hydrogen diffusion activation energy of 1.5-2.0 eV. This effectively prevents hydrogen atoms from escaping during high-temperature sintering, thereby improving the hydrogen passivation effect. Moreover, during metal ablation, the damaged hydrogen-fixing layer 220 releases a large number of hydrogen atoms, which can effectively passivate the metal-semiconductor contact area, thereby improving the photoelectric conversion efficiency of the photovoltaic cell.

[0046] The photovoltaic cell provided in this application embodiment includes a substrate 100 and a passivation and antireflection layer 200. The passivation and antireflection layer 200 includes a dielectric layer 210 and a hydrogen solidification layer 220, with the spacing between the hydrogen solidification layers 220 being less than or equal to 0.074 nm. By setting the substrate 100 to support the passivation and antireflection layer 200 and to absorb sunlight and generate charge carriers, by setting the dielectric layer 210 to adjust the optical properties of the photovoltaic cell such as the refractive index, and by setting the hydrogen solidification layer 220 with its lattice spacing within 0.074 nm, during the high-temperature fabrication process, the physical barrier or chemical adsorption effect of the hydrogen solidification layer 220 is used to suppress the outward escape of hydrogen atoms. During the metal ablation process, the hydrogen solidification layer 220 can improve the passivation effect by releasing hydrogen atoms, thereby improving the passivation effect of the metal-semiconductor interface region. The stacked structure of dielectric layer 210 and hydrogen fixation layer 220 forms an interface barrier, which can reduce the path of hydrogen outward. The dielectric layer 210 and hydrogen fixation layer 220 work together to maintain a high hydrogen retention rate in high-temperature processes, avoiding problems such as interface defect regeneration and passivation performance degradation caused by hydrogen escape, thereby improving the photoelectric conversion efficiency, open-circuit voltage and other performance of photovoltaic cells.

[0047] In one possible implementation, the hydrogen fixation layer 220 includes at least one of silicon oxide (SiOx), aluminum oxide (AlOx), silicon nitride (SiNx), and silicon oxynitride (SiOxNy).

[0048] It should be noted that the lattice gap of silicon oxide (SiOx) is 0.05 nm, the lattice gap of aluminum oxide (AlOx) is 0.06 nm, and the lattice gap of silicon nitride (SiNx) and silicon oxynitride (SiOxNy) is 0.074 nm. This satisfies the requirement that the lattice gap of the hydrogen fixation layer 220 is less than or equal to 0.074 nm, thereby effectively suppressing the outward escape of hydrogen atoms during the high-temperature preparation process through the hydrogen fixation layer 220.

[0049] The physical barrier effect of silicon oxide (SiOx) and aluminum oxide (AlOx), and the synergistic optimization of the chemical bonding effect of silicon nitride (SiNx) and silicon oxynitride (SiOxNy) enhance the ability to suppress hydrogen escape. Furthermore, the dielectric properties of silicon oxide (SiOx) assist in interface passivation and reduce interface defect density. In this way, photovoltaic cells can maintain a high hydrogen retention rate during high-temperature processes, avoiding the passivation performance degradation caused by hydrogen escape, thereby improving the conversion efficiency and lifespan of photovoltaic cells.

[0050] For example, the hydrogen fixation layer 220 may include One or more of these materials can be used to improve the process compatibility of the hydrogen fixation layer 220 through the diversity of material selection.

[0051] When the passivation antireflection layer 200 has multiple hydrogen solidification layers 220, the material of each hydrogen solidification layer 220 can be the same, or the material of some hydrogen solidification layers 220 can be the same, or the material of each hydrogen solidification layer 220 can be different. This embodiment does not impose any restrictions on this.

[0052] It should be noted that when the hydrogen fixation layer 220 includes SiNx, unlike the SiNx in related technologies, in this embodiment, the SiNx is nitrided to form nitrided SiNx. For example, the SiNx can be nitrided by introducing NH3 at 2000-20000 sccm. This makes the hydrogen fixation layer 220 more compact, thereby reducing its lattice gaps and preventing hydrogen atoms from escaping.

[0053] Reference Figure 1 and Figure 2 As shown, in one possible implementation, the passivation antireflection layer 200 includes at least two dielectric layers 210, with the at least two dielectric layers 210 and at least one hydrogen solidification layer 220 alternately stacked. The at least two dielectric layers 210 include a first dielectric layer 211 and a second dielectric layer 212, with the first dielectric layer 211 disposed close to the substrate 100 relative to the second dielectric layer 212, and the refractive index of the first dielectric layer 211 being greater than the refractive index of the second dielectric layer 212.

[0054] In this way, light interference and antireflection are achieved through the refractive index gradient changes of multiple dielectric layers 210, thereby reducing light reflection loss. The first dielectric layer 211 is disposed close to the substrate 100, and the second dielectric layer 212 is disposed away from the substrate 100. The high refractive index of the first dielectric layer 211 and the low refractive index of the second dielectric layer 212 are arranged sequentially, which can optimize the optical performance of the photovoltaic cell. Furthermore, the first dielectric layer 211, the hydrogen fixation layer 220, and the second dielectric layer 212 are stacked sequentially to form a highly dense passivation and antireflection layer 200, thereby reducing hydrogen escape paths.

[0055] Reference Figures 1 to 4As shown, in some embodiments, dielectric layer 210 further includes a third dielectric layer 213, and a second dielectric layer 212 is located between the first dielectric layer 211 and the third dielectric layer 213, wherein the refractive index of the second dielectric layer 212 is greater than the refractive index of the third dielectric layer 213.

[0056] In other words, the refractive indices of the first dielectric layer 211, the second dielectric layer 212, and the third dielectric layer 213 decrease sequentially. For example, the refractive index of the first dielectric layer 211 is greater than 2.0, the refractive index of the second dielectric layer 212 is between 1.8 and 2.0, and the refractive index of the third dielectric layer 213 is between 1.3 and 1.8.

[0057] Thus, the passivation antireflection layer 200 has dielectric layers 210 with high, medium and low refractive indices arranged in sequence, which can optimize the refractive index gradient of the passivation antireflection layer 200, reduce light reflection loss, and the refractive index gradient design of the dielectric layer 210 and the physical barrier effect of the hydrogen fixation layer 220 work together to improve the conversion efficiency of the photovoltaic cell and also improve the hydrogen emission suppression capability of the photovoltaic cell.

[0058] The first dielectric layer 211, the hydrogen solidification layer 220, the second dielectric layer 212, and the third dielectric layer 213 can be stacked sequentially to form... Figure 1 The schematic diagram shows a passivation and antireflection layer 200. Alternatively, a hydrogen solidification layer 220 can be formed between the first dielectric layer 211 and the second dielectric layer 212, between the second dielectric layer 212 and the third dielectric layer 213, and on the side of the third dielectric layer 213 facing away from the second dielectric layer 212. Figure 3 and Figure 4 The passivation and anti-reflection layer 200 is shown in the diagram.

[0059] Reference Figure 3 , Figure 4 As shown, in one possible implementation, the hydrogen fixation layer 220 includes a first hydrogen fixation layer 221, a second hydrogen fixation layer 222, and a third hydrogen fixation layer 223, wherein the first dielectric layer 211, the first hydrogen fixation layer 221, the second dielectric layer 212, the second hydrogen fixation layer 222, the third dielectric layer 213, and the third hydrogen fixation layer 223 are stacked sequentially.

[0060] In this way, the alternating stacking of dielectric layer 210 and hydrogen solidification layer 220 forms a periodic stacked structure, which increases the density of passivation and antireflection layer 200. This effectively slows down the ablation rate of the slurry during metal ablation, reduces the combined damage from slurry corrosion, and helps reduce the thickness of the doped layer, thereby reducing parasitic absorption and improving the conversion efficiency of the photovoltaic cell. Furthermore, the refractive indices of the first dielectric layer 211, the second dielectric layer 212, and the third dielectric layer 213 decrease sequentially, which effectively optimizes the optical properties of passivation and antireflection layer 200, thereby improving the conversion efficiency of the photovoltaic cell.

[0061] It should be understood that the first hydrogen fixation layer 221, the second hydrogen fixation layer 222, and the third hydrogen fixation layer 223 can all be made of the same material, for example, one of silicon oxide SiOx, aluminum oxide AlOx, silicon nitride SiNx, and silicon oxynitride SiOxNy. The first hydrogen fixation layer 221, the second hydrogen fixation layer 222, and the third hydrogen fixation layer 223 can each be made of different materials, for example, the first hydrogen fixation layer 221 is a silicon oxide film, the second hydrogen fixation layer 222 is an aluminum oxide film, and the third hydrogen fixation layer 223 is a silicon nitride film.

[0062] Reference Figures 1 to 4 As shown, in one possible implementation, the photovoltaic cell further includes a metal electrode 300, which is located on at least one side of the substrate 100 in the thickness direction and extends through at least one passivation antireflection layer 200 to opposite sides.

[0063] In this embodiment, the metal electrode 300 refers to a conductive structure used for collecting current. The metal electrode 300 may include a first metal electrode 310 and a second metal electrode 320, where one of the first metal electrode 310 and the second metal electrode 320 is a positive electrode and the other is a negative electrode. The metal electrode 300 penetrates both sides of the passivation antireflection layer 200 to ensure efficient current collection. For example, in Figure 2 and Figure 4 In the process, the first metal electrode 310 and the second metal electrode 320 are respectively disposed on the front and back sides of the photovoltaic cell. Figure 1 and Figure 3 In the process, the first metal electrode 310 and the second metal electrode 320 are both located on the back side of the photovoltaic cell.

[0064] Reference Figures 1 to 4 As shown, in one possible implementation, at least one passivation antireflection layer 200 further includes a hydrogen release layer 230, which penetrates all dielectric layers 210 and all hydrogen solidification layers 220, and is located on opposite sides of the metal electrode 300.

[0065] It should be noted that when the metal electrode 300 is disposed on one side of the photovoltaic cell, the passivation antireflection layer 200 on the same side as the metal electrode 300 is provided with a hydrogen release layer 230. When the metal electrode 300 is disposed on both sides of the photovoltaic cell, the passivation antireflection layer 200 on both sides of the photovoltaic cell is provided with a hydrogen release layer 230. The hydrogen release layer 230 provides a release path for hydrogen atoms by penetrating all dielectric layers 210 and all hydrogen solidification layers 220, thereby passivating the interface region of metal electrode 300-dielectric layer 210 and metal electrode 300-hydrogen solidification layer 220 to reduce carrier recombination.

[0066] Reference Figures 1 to 4As shown, in one possible implementation, the photovoltaic cell further includes a tunneling oxide layer 400 and a first passivation layer 500, the first passivation layer 500 and the tunneling oxide layer 400 being disposed on opposite sides of the substrate 100 in the thickness direction. There are two passivation antireflection layers 200: one passivation antireflection layer 200 is disposed on the side of the first passivation layer 500 facing away from the substrate 100, and the other passivation antireflection layer 200 is disposed on the side of the tunneling oxide layer 400 facing away from the substrate 100.

[0067] In other words, both the front and back sides of the photovoltaic cell are provided with a passivation and antireflection layer 200 to effectively suppress the outward diffusion of hydrogen atoms, thereby improving its passivation effect.

[0068] Reference Figure 1 and Figure 3 As shown, in some embodiments, the photovoltaic cell further includes a second passivation layer 900, with the first passivation layer 500 and the second passivation layer 900 located on opposite sides of the substrate 100.

[0069] Reference Figure 3 As shown, in some embodiments, the photovoltaic cell further includes a first doped layer 600, which is located between the tunneling oxide layer 400 and the passivation and antireflection layer 200. The first doped layer 600 can be used to adjust the carrier concentration. Since the photovoltaic cell in this embodiment uses a passivation and antireflection layer 200 composed of three or more dielectric layers 210 and three or more hydrogen solidification layers 220 stacked alternately, the passivation and antireflection layer 200 has high density, which reduces the rate at which the slurry corrodes the hydrogen solidification layer 220, thereby increasing the process window and allowing for a thinner first doped layer 600, thus improving the efficiency of the photovoltaic cell.

[0070] Understandably, for Figure 1 and Figure 3 In the case of the BC structure photovoltaic cell, the first doped layer 600 may include a first sub-doped layer 610 and a second sub-doped layer 620. The first sub-doped layer 610 may be phosphorus-doped Poly-Si, and the second sub-doped layer 620 may be boron-doped Poly-Si.

[0071] Reference Figure 2 , Figure 4 As shown, in some embodiments, the photovoltaic cell further includes a second doped layer 700 and an emitter 800, wherein the second doped layer 700 is located between the tunneling oxide layer 400 and the passivation antireflection layer 200, and the emitter 800 is located between the substrate 100 and the first passivation layer 500.

[0072] In other words, for Figure 2 and Figure 4 In the case of the TOPCon structure photovoltaic cell, there is an emitter 800 on the front side and a second doped layer 700 on the back side. The second doped layer 700 can be phosphorus-doped Poly-Si.

[0073] Since the photovoltaic cell in this embodiment uses a passivation and antireflection layer 200 composed of three or more dielectric layers 210 and three or more hydrogen solidification layers 220 stacked alternately, the passivation and antireflection layer 200 has high density, which can reduce the rate of slurry corrosion of the hydrogen solidification layer 220 during metal ablation, thereby increasing the process window and thinning the emitter 800, thereby improving the efficiency of the photovoltaic cell.

[0074] The following is a brief description of the preparation and testing process of the photovoltaic cells in the embodiments of this application.

[0075] The following steps can be used to prepare the following: Figure 2 A schematic diagram of a photovoltaic cell.

[0076] 1. Substrate 100 uses an N-type silicon wafer, which is textured to form a pyramidal textured surface.

[0077] Second, the textured silicon wafer undergoes high-temperature boron diffusion to form a P+ structure, which forms a PN junction with the N-type silicon substrate.

[0078] III. After boron diffusion, silicon wafers are alkali-polished to obtain silicon wafers with a back-side reflectivity of ≥50%.

[0079] IV. A tunneling oxide layer 400 was prepared on the back side using PECVD.

[0080] 5. A phosphorus-doped amorphous silicon layer is prepared on the back side of the tunnel oxide layer 400.

[0081] 6. High-temperature annealing is used on N-type silicon wafers to convert amorphous silicon into polycrystalline silicon and activate the internal phosphorus atoms to induce diffusion bonding.

[0082] 7. Etch and clean the N-type silicon wafer to remove the front-side BSG, BSG wrap-around plating, and back-side mask layer.

[0083] 8. A first passivation layer 500 is prepared on the front side of an N-type silicon wafer. The first passivation layer 500 is an aluminum oxide film layer.

[0084] 9. A first dielectric layer 211, a hydrogen fixation layer 220, a second dielectric layer 212, and a third dielectric layer 213 are sequentially prepared on the front side of an N-type silicon wafer. The first dielectric layer 211 is a silicon nitride film, the hydrogen fixation layer 220 is a silicon oxide layer, the second dielectric layer 212 is a silicon oxynitride layer, and the third dielectric layer 213 is a silicon oxide layer.

[0085] 10. A first dielectric layer 211, a hydrogen fixation layer 220, a second dielectric layer 212, and a third dielectric layer 213 are sequentially prepared on the back side of an N-type silicon wafer. The first dielectric layer 211, the second dielectric layer 212, and the third dielectric layer 213 are all silicon nitride layers, and the hydrogen fixation layer 220 is a silicon oxide film layer.

[0086] 11. Perform front and back side screen printing and light injection treatment on the silicon wafer.

[0087] The following steps can be used to prepare the following: Figure 3 A schematic diagram of a photovoltaic cell.

[0088] 1. Substrate 100 uses an N-type silicon wafer. The N-type silicon wafer is subjected to RCA cleaning and double-sided polishing to form a double-polished wafer with a reflectivity ≥50%.

[0089] II. Tunneling oxide layer 400 and intrinsic amorphous silicon were prepared on the back side using LPCVD.

[0090] Third, boron diffusion is used on N-type silicon wafers to form boron diffused emitter 800, while converting amorphous silicon into polycrystalline silicon.

[0091] IV. Laser grooving of the phosphorus-doped Poly-Si region of the N-type silicon wafer.

[0092] 5. Etch and clean the N-type silicon wafer to remove the front and back side masks, the front and side Poly-Si winding plating, and the film layer in the trench area.

[0093] VI. LPCVD was used to prepare a 400 nm tunneling oxide layer and an intrinsic amorphous silicon layer of 60-350 nm on the back side.

[0094] 7. High-temperature annealing is used on N-type silicon wafers to convert amorphous silicon into polycrystalline silicon and activate the internal phosphorus atoms to induce diffusion bonding.

[0095] 8. Laser grooving of the boron-doped Poly-Si region of the N-type silicon wafer.

[0096] 9. Etch and clean the N-type silicon wafer to remove the front and back side masks, the front and side Poly-Si winding plating, and the film layer in the trench area.

[0097] 10. A first passivation layer 500 and a second passivation layer 900 are prepared on the front and back sides of an N-type silicon wafer, respectively. Both the first passivation layer 500 and the second passivation layer 900 are aluminum oxide films.

[0098] 11. A first dielectric layer 211, a first hydrogen fixation layer 221, a second dielectric layer 212, a second hydrogen fixation layer 222, a third dielectric layer 213, and a third hydrogen fixation layer 223 are sequentially fabricated on the front side of an N-type silicon wafer. The first hydrogen fixation layer 221 is a SiNx nitride film, the second hydrogen fixation layer 222 is a SiOxNy nitride film, and the third hydrogen fixation layer 223 is a SiOx nitride film. The SiNx film is nitrided by introducing NH3 at a rate of 2000-20000 sccm to form the SiNx nitride film, the SiOxNy film is nitrided by introducing NH3 at a rate of 2000-20000 sccm to form the SiOx nitride film, and the SiOx film is nitrided by introducing NH3 at a rate of 2000-20000 sccm to form the SiOx nitride film. The first dielectric layer 211 is a silicon nitride film, the second dielectric layer 212 is a silicon oxynitride film, and the third dielectric layer 213 is a silicon oxide film.

[0099] 12. A first dielectric layer 211, a first hydrogen fixation layer 221, a second dielectric layer 212, a third dielectric layer 213, and a third hydrogen fixation layer 223 are sequentially fabricated on the back side of an N-type silicon wafer. The first hydrogen fixation layer 221, the second hydrogen fixation layer 222, and the third hydrogen fixation layer 223 are all SiNx nitride films. The SiNx films are nitrided by introducing NH3 at a rate of 2000-20000 sccm to form SiNx nitride films. The first dielectric layer 211, the second dielectric layer 212, and the third dielectric layer 213 are all silicon nitride films.

[0100] Thirteen, perform back-side screen printing and photoinjection on the silicon wafer.

[0101] The following describes the relevant tests and test results of the photovoltaic cells of Examples 1 to 3 and Comparative Examples 1 to 3.

[0102] The photovoltaic cell fabrication process in Example 1:

[0103] 1. Substrate 100 uses an N-type silicon wafer, which is textured to form a pyramidal textured surface.

[0104] Second, the textured silicon wafer undergoes high-temperature boron diffusion to form a P+ structure, which forms a PN junction with the N-type silicon substrate.

[0105] 3. The silicon wafers after boron diffusion are then subjected to alkaline polishing.

[0106] IV. A tunneling oxide layer 400 was prepared on the back side using PECVD.

[0107] 5. Prepare a phosphorus-doped amorphous silicon layer on the back side of the tunnel oxide layer 400.

[0108] 6. High-temperature annealing is used on N-type silicon wafers to convert amorphous silicon into polycrystalline silicon and activate the internal phosphorus atoms to induce diffusion bonding.

[0109] 7. Etch and clean the N-type silicon wafer to remove the front-side BSG, BSG wrap-around plating, and back-side mask layer.

[0110] 8. A first passivation layer 500 is prepared on the front side of an N-type silicon wafer. The first passivation layer 500 is an aluminum oxide film layer.

[0111] 9. A first dielectric layer 211, a first hydrogen fixation layer 221, a second dielectric layer 212, a third dielectric layer 213, and a third hydrogen fixation layer 223 are sequentially fabricated on the front side of an N-type silicon wafer. The first hydrogen fixation layer 221, the second hydrogen fixation layer 222, and the third hydrogen fixation layer 223 are all silicon oxide films, the first dielectric layer 211 is a silicon nitride film, the second dielectric layer 212 is a silicon oxynitride film, and the third dielectric layer 213 is a silicon oxide film.

[0112] 10. A first dielectric layer 211, a first hydrogen fixation layer 221, a second dielectric layer 212, a second hydrogen fixation layer 222, a third dielectric layer 213, and a third hydrogen fixation layer 223 are sequentially fabricated on the back side of an N-type silicon wafer. The first hydrogen fixation layer 221, the second hydrogen fixation layer 222, and the third hydrogen fixation layer 223 are all silicon oxide films, and the first dielectric layer 211, the second dielectric layer 212, and the third dielectric layer 213 are all silicon nitride films.

[0113] 11. Perform front and back side screen printing and light injection treatment on the silicon wafer.

[0114] The difference between Example 2 and Example 1 is that the hydrogen fixation layer 220 is an aluminum oxide film layer, so that the lattice gap of the hydrogen fixation layer 220 is 0.06 nm.

[0115] The difference between Example 3 and Example 1 is that the hydrogen fixation layer 220 is a SiNx nitride film, so that the lattice gap of the hydrogen fixation layer 220 is 0.074 nm.

[0116] The difference between Comparative Example 1 and Example 1 is that the hydrogen fixation layer 220 was not provided.

[0117] The difference between Comparative Example 2 and Example 1 is that the hydrogen fixation layer 220 is Zr6C. 48 H 28 O 32 Its lattice gap is 0.8 nm.

[0118] The difference between Comparative Example 3 and Example 1 is that the hydrogen fixation layer 220 is C. 24 H2O 32 Zr6 has a lattice gap of 1.00 nm.

[0119] Lattice gap testing methods: The first method involves acquiring images using a high-resolution TEM, processing the images, drawing straight lines along the lattice fringes, measuring the total length of multiple lattice gaps, and then dividing by the number of lattices to obtain the individual lattice gap.

[0120] The second method involves using XRD to measure the diffraction angles corresponding to the diffraction peaks and then calculating the lattice interstices using Bragg's formula. Bragg's formula... λ is the X-ray wavelength, d is the interplanar spacing, θ is the diffraction angle, and n is the diffraction order, which can be 1, 2, 5, etc.

[0121] Photovoltaic conversion efficiency and open-circuit voltage test method: The positive and negative electrode probes are contacted with the positive and negative main grids of the solar cell respectively, and the performance is tested using the Halm system.

[0122] The specific steps are as follows: 1. Make precise and stable contact between the positive and negative electrode probes and the positive and negative main busbars of the photovoltaic cell.

[0123] 2. Turn on the solar simulator to ensure that the light shines evenly on the entire effective area of ​​the photovoltaic cell.

[0124] Standard test conditions: light intensity 1000W / m², spectrum AM1.5G, temperature: 25°C.

[0125] 3. The test system automatically performs a rapid voltage scan and simultaneously measures the current. It starts in the short-circuit state (maximum current, zero voltage) and ends in the open-circuit state (zero current, maximum voltage), thus obtaining an IV characteristic curve. The open-circuit voltage and maximum output power can be read from the IV curve, and the photoelectric conversion efficiency can be calculated using the following formula.

[0126] Photoelectric conversion efficiency (%) = (Maximum output power Pmax) / (Incident light power Pin) × 100%

[0127] Table 1. Structural parameters and test results of photovoltaic cells

[0128]

[0129] As shown in Table 1 above, in Examples 1 to 3, the lattice gap of the hydrogen solidification layer 220 is less than or equal to 0.074 nm, and the photoelectric conversion efficiency and open circuit voltage of Examples 1 to 3 are relatively high. However, in Comparative Example 1, no passivation antireflection layer was provided, and the lattice gap of the hydrogen solidification layer 220 in Comparative Example 2 and Comparative Example 3 is greater than 0.074 nm, and the photoelectric conversion efficiency and open circuit voltage of Comparative Example 1 to Comparative Example 3 are relatively low.

[0130] Based on the above embodiments, this application also provides a photovoltaic module, which includes a plurality of photovoltaic cells, a panel and a backsheet. The plurality of photovoltaic cells form a battery unit, which is disposed between the panel and the backsheet. The panel is disposed on the light-facing side of the photovoltaic module, and the backsheet is disposed on the backlight-receiving side of the photovoltaic module.

[0131] The structure and working principle of photovoltaic cells have been described in detail in the foregoing embodiments, and will not be repeated here.

[0132] Based on the above embodiments, this application also provides a photovoltaic system, which includes photovoltaic cells or photovoltaic modules. The structure and working principle of the photovoltaic cells and modules have been described in detail in the foregoing embodiments and will not be repeated here. The photovoltaic system is used to convert solar energy into electrical energy and supply it to electrical loads.

[0133] Based on the above embodiments, this application also provides an electrical device, which includes a photovoltaic cell or a photovoltaic module. The structure and working principle of the photovoltaic cell and the photovoltaic module have been described in detail in the foregoing embodiments, and will not be repeated here.

[0134] Electrical equipment also includes electrical devices, and photovoltaic cells or photovoltaic modules are used to supply power to the electrical devices.

[0135] For example, the electrical equipment can be a vehicle, the electrical device can be an electric motor, and the generator can provide electrical energy to the electric motor, which can then convert electrical energy into mechanical energy. As another example, the electrical equipment can be a lamp, the electrical device can be a light source, and the generator can convert sunlight into electrical energy, which is then provided to the light source. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A photovoltaic cell, characterized in that, include: Substrate (100); At least one passivation antireflection layer (200) is disposed on at least one side of the substrate (100) in the thickness direction. The passivation antireflection layer (200) includes at least one dielectric layer (210) and at least one hydrogen solid layer (220). At least one dielectric layer (210) and at least one hydrogen solid layer (220) are stacked. At least one dielectric layer (210) is disposed close to the substrate (100) relative to at least one hydrogen solid layer (220). The lattice gap of the hydrogen solid layer (220) is less than or equal to 0.074 nm.

2. The photovoltaic cell according to claim 1, characterized in that, The hydrogen-fixing layer (220) includes at least one of silicon oxide, aluminum oxide, silicon nitride, and silicon oxynitride; And / or, the hydrogen fixation layer (220) includes Si-N bonds and Si-O bonds.

3. The photovoltaic cell according to claim 1, characterized in that, The passivation antireflection layer (200) includes at least two dielectric layers (210), and at least two dielectric layers (210) and at least one hydrogen solidification layer (220) are stacked alternately; At least two of the dielectric layers (210) include a first dielectric layer (211) and a second dielectric layer (212), wherein the first dielectric layer (211) is disposed close to the substrate (100) relative to the second dielectric layer (212), and the refractive index of the first dielectric layer (211) is greater than the refractive index of the second dielectric layer (212).

4. The photovoltaic cell according to claim 3, characterized in that, The dielectric layer (210) further includes a third dielectric layer (213), and the second dielectric layer (212) is located between the first dielectric layer (211) and the third dielectric layer (213), wherein the refractive index of the second dielectric layer (212) is greater than the refractive index of the third dielectric layer (213).

5. The photovoltaic cell according to claim 4, characterized in that, The hydrogen fixation layer (220) includes a first hydrogen fixation layer (221), a second hydrogen fixation layer (222), and a third hydrogen fixation layer (223), wherein the first dielectric layer (211), the first hydrogen fixation layer (221), the second dielectric layer (212), the second hydrogen fixation layer (222), the third dielectric layer (213), and the third hydrogen fixation layer (223) are stacked sequentially.

6. The photovoltaic cell according to any one of claims 1-5, characterized in that, Also includes: A metal electrode (300) is located on at least one side of the substrate (100) in the thickness direction, and the metal electrode (300) penetrates at least one of the passivation antireflection layers (200) on opposite sides; at least one of the passivation antireflection layers (200) further includes a hydrogen release layer (230), the hydrogen release layer (230) penetrates all of the dielectric layers (210) and all of the hydrogen fixation layers (220), and the hydrogen release layer (230) is located on opposite sides of the metal electrode (300).

7. The photovoltaic cell according to any one of claims 1-5, characterized in that, Also includes: A tunneling oxide layer (400) and a first passivation layer (500) are provided on opposite sides of the substrate (100) in the thickness direction. There are two passivation antireflection layers (200). One passivation antireflection layer (200) is disposed on the side of the first passivation layer (500) away from the substrate (100), and the other passivation antireflection layer (200) is disposed on the side of the tunneling oxide layer (400) away from the substrate (100).

8. The photovoltaic cell according to claim 7, characterized in that, Also includes: A first doped layer (600) is located between the tunneling oxide layer (400) and the passivation antireflection layer (200); Alternatively, it may include a second doped layer (700) and an emitter (800), the second doped layer (700) being located between the tunneling oxide layer (400) and the passivation antireflection layer (200), and the emitter (800) being located between the substrate (100) and the first passivation layer (500).

9. A photovoltaic module, characterized in that, include: The photovoltaic cell as described in any one of claims 1-8.

10. An electrical appliance, characterized in that, include: The photovoltaic cell as described in any one of claims 1-8, or the photovoltaic module as described in claim 9.

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