A solar cell and photovoltaic module

Abstract

The application discloses a solar cell and a photovoltaic module, and relates to the technical field of photovoltaics, and aims to balance the passivation performance and contact performance of the surface of a solar cell to improve the photoelectric efficiency of the solar cell. The solar cell comprises a first surface of a semiconductor substrate, the first surface comprising a first electrode region and a first non-electrode region, a first doped semiconductor layer being arranged in the first electrode region, a second doped semiconductor layer being arranged in the first non-electrode region or the first non-electrode region being free of a doped semiconductor layer, the first doped semiconductor layer having a higher doping concentration than the second doped semiconductor layer, and the semiconductor substrate, the first doped semiconductor layer, the second doped semiconductor layer and a first passivation and anti-reflection layer containing an antimony element. In the first electrode region, the maximum peak concentration of the antimony element in the first doped semiconductor layer and the first passivation and anti-reflection layer is n1. In the first non-electrode region, the maximum peak concentration of the antimony element in the second doped semiconductor layer and the first passivation and anti-reflection layer is n2, and n1 is greater than n2.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic technology, and more particularly to a solar cell and a photovoltaic module. Background Technology

[0002] A solar cell is a device that utilizes solar energy to directly convert light energy into electrical energy through the photoelectric effect or photochemical effect.

[0003] Currently, there have been many improvements in battery structure. However, how to balance the passivation and contact properties of solar cell surfaces to ultimately improve the photoelectric efficiency of solar cells remains a pressing technical problem for the industry. Summary of the Invention

[0004] The purpose of this invention is to provide a solar cell and a photovoltaic module for improving the photoelectric efficiency of solar cells.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a solar cell. The solar cell includes: a semiconductor substrate, a first doped semiconductor layer, a second doped semiconductor layer, a first passivation antireflection layer, and a first electrode. The semiconductor substrate is doped with antimony, and along the thickness direction of the semiconductor substrate, the semiconductor substrate includes opposing first and second surfaces. The first surface includes a first electrode region and a first non-electrode region, with a height difference between the first electrode region and the first non-electrode region. The first doped semiconductor layer is located in the first electrode region, and the second doped semiconductor layer is located in the first non-electrode region. The doping concentration of the first doped semiconductor layer is greater than the doping concentration of the second doped semiconductor layer; or, the first doped semiconductor layer is located in the first electrode region, and no doped semiconductor layer is disposed on the first non-electrode region. The first passivation antireflection layer is disposed at least on the first doped semiconductor layer and the second doped semiconductor layer. The first electrode is located in the first electrode region and is electrically connected to the first doped semiconductor layer through the first passivation antireflection layer. The first doped semiconductor layer, the second doped semiconductor layer, and the first passivation antireflection layer all contain antimony. Within the first electrode region, the maximum peak concentration of antimony in the first doped semiconductor layer and the first passivation antireflection layer is n1. Within the first non-electrode region, the maximum peak concentration of antimony in the second doped semiconductor layer and the first passivation antireflection layer is n2. Where n1 is greater than n2.

[0006] In the solar cell provided by this invention, the doping concentration of the first doped semiconductor layer disposed in the first electrode region is greater than the doping concentration of the second doped semiconductor layer disposed in the first non-electrode region. By reducing the doping concentration in the first non-electrode region or by not disposing of a doped semiconductor layer in the first non-electrode region, the high-concentration area on the first surface of the solar cell is reduced, mitigating recombination problems on the semiconductor substrate surface caused by high doping concentration and increasing the open-circuit voltage of the cell. Simultaneously, the presence of a first doped semiconductor layer with a higher doping concentration in the first electrode region ensures a lower contact resistance between the first electrode and the first doped semiconductor layer, reducing the cell's series resistance, increasing the fill factor, and thus improving the efficiency of the solar cell. Due to the height difference between the first electrode region and the first non-electrode region, light can be reflected and absorbed within the groove, reducing reflectivity.

[0007] The semiconductor substrate, the second doped semiconductor layer, and the first doped semiconductor layer contain antimony. The distribution of antimony helps to reduce its resistivity, improve the conductivity of the first electrode region, and reduce the transport loss of charge carriers in the first non-electrode region due to the reduced concentration of the doped layer. The first passivation antireflection layer also contains antimony. Antimony can reduce the film bursting phenomenon of the passivation layer and improve the chemical passivation performance of the passivation layer, thereby enhancing the passivation capability of the first passivation antireflection layer. Utilizing the steric hindrance effect caused by the lattice distortion generated by the antimony in the first doped semiconductor layer and the first passivation antireflection layer, the diffusion and accumulation of transition metal impurities such as Fe and Cu in the first electrode can be effectively hindered or suppressed within the aforementioned film layers, thus preventing the diffusion of metal elements in the first electrode. Furthermore, since there is no grid line obstruction in the first non-electrode region, the first non-electrode region focuses on balancing the light trapping effect and passivation performance of the first surface of the solar cell, while the first electrode region focuses on balancing contact performance and passivation performance.

[0008] Based on the above description, n1 is greater than n2. The first electrode region is provided with a first doped semiconductor layer and a first electrode, both with a higher doping concentration. The first electrode region needs to balance the contact performance between the first electrode and the first doped semiconductor layer, as well as the passivation performance. This arrangement improves the conductivity of the first doped semiconductor layer and enhances the contact performance between the first electrode and the first doped semiconductor layer. Simultaneously, the enhanced passivation performance of the first passivation antireflection layer and its diffusion-blocking effect on metal elements by antimony element balance the transport performance and passivation performance of the first electrode region. Furthermore, although the doping concentration of the second doped semiconductor layer in the first non-electrode region is lower, or no doped semiconductor layer is provided in the first non-electrode region, reducing recombination problems caused by high doping concentration, it also reduces the lateral transport capability of charge carriers in the first non-electrode region. Antimony element can reduce the resistivity of the semiconductor substrate, reduce the transport loss of charge carriers in the first non-electrode region, and further improve the passivation of the surface passivation layer of the first non-electrode region.

[0009] In summary, the structural arrangement of the first electrode region and the first non-electrode region on the first surface, combined with the differentiated setting of antimony element concentration in the two regions, can improve the passivation performance of the first surface of the solar cell while satisfying its transmission performance, thereby further improving the open-circuit voltage and the final cell efficiency.

[0010] In one implementation, the first passivation antireflection layer includes at least an aluminum oxide layer. Within the first non-electrode region, the peak concentration of antimony in the second doped semiconductor layer and the peak concentration of antimony in the semiconductor substrate are both lower than the peak concentration of antimony in the aluminum oxide layer. Within the first electrode region, the peak concentration of antimony in the first doped semiconductor layer and the peak concentration of antimony in the semiconductor substrate are both lower than the peak concentration of antimony in the aluminum oxide layer.

[0011] With the above technical solution, antimony enters the alumina layer through lattice substitution or interstitial doping. On the one hand, it acts as a strong hydrogen trap to bind hydrogen atoms, delaying the rapid evolution and accumulation of hydrogen during high-temperature processes and preventing hydrogen-induced blistering. On the other hand, it regulates the lattice expansion of alumina, reducing the mismatch in its thermal expansion coefficient with the silicon substrate and releasing internal stress in the film. Simultaneously, antimony segregates at the silicon / alumina interface to form stable Sb-Si and Sb-O-Al bridging bonds, strengthening the interfacial bonding and passivating interfacial defects. Furthermore, the lattice distortion introduced by antimony doping can passivate microcracks and improve the toughness of the film, ultimately significantly reducing the risk of cracking and peeling of the alumina layer during high-temperature sintering and long-term service, while maintaining and optimizing its passivation performance.

[0012] In one implementation, the first passivation antireflection layer includes an aluminum oxide layer and an antireflection layer. The aluminum oxide layer is disposed on a first doped semiconductor layer and a second doped semiconductor layer, and the antireflection layer is disposed on the side of the aluminum oxide layer facing away from the semiconductor substrate. In the first non-electrode region, the distance between the side of the antireflection layer facing away from the semiconductor substrate and the location of the peak concentration of antimony in the aluminum oxide layer is a first distance. In the first electrode region, the distance between the side of the antireflection layer facing away from the semiconductor substrate and the location of the peak concentration of antimony in the aluminum oxide layer is a second distance. The directions of both the first and second distances are consistent with the thickness direction of the semiconductor substrate. The first distance is less than the second distance, and / or the first distance ranges from 60 nm to 150 nm, and / or the second distance ranges from 80 nm to 180 nm.

[0013] With the above technical solution, the distribution of antimony in the first electrode region in the first passivation antireflection layer is closer to the surface of the silicon substrate, which is more conducive to the segregation of antimony at the silicon / alumina interface to form stable Sb-Si bonds and Sb-O-Al bridge bonds, thereby strengthening the interface bonding force and passivating interface defects.

[0014] In one implementation, the peak concentration of antimony in the first doped semiconductor layer located in the first electrode region is greater than the peak concentration of antimony in the second doped semiconductor layer located in the first non-electrode region.

[0015] Using the above technical solution, antimony can reduce the resistivity of the doped semiconductor layer and improve the conductivity of the first doped semiconductor layer. Furthermore, setting a higher concentration of antimony in the first doped semiconductor layer is beneficial for enhancing the contact performance between the first electrode and the first doped semiconductor layer.

[0016] In one implementation, the peak concentration of antimony in the first doped semiconductor layer located in the first electrode region ranges from 2 × 10⁻⁶. 15 atom / cm 3 Up to 2×10 18 atom / cm 3 .

[0017] When the above technical solution is adopted, the peak concentration of antimony is less than 2×10 15 atom / cm 3 When the concentration of antimony is greater than 2 × 10⁻⁶, its effect on reducing the resistivity of the first doped semiconductor layer is relatively weak, thus affecting the conductivity of the first doped semiconductor layer. 18 atom / cm 3 If the lattice distortion of the first doped semiconductor layer is too large, it will reduce the passivation performance of the first doped semiconductor layer. Based on this, this application sets the peak concentration of antimony in the first doped semiconductor layer located in the first electrode region within the above-mentioned range, thus balancing the conductivity and passivation performance of the first doped semiconductor layer.

[0018] In one implementation, the peak concentration of antimony in the second doped semiconductor layer located in the first non-electrode region ranges from 1 × 10⁻⁶. 15 atom / cm 3 Up to 1×10 18 atom / cm 3 .

[0019] In one implementation, the first passivation antireflection layer includes at least an aluminum oxide layer, and the thickness of the aluminum oxide layer located in the first electrode region is greater than the thickness of the aluminum oxide layer located in the first non-electrode region.

[0020] When using the above technical solution, the doping concentration of the first doped semiconductor layer in the first electrode region is higher than that of the second doped semiconductor layer in the first non-electrode region, resulting in an enhanced recombination effect in the first electrode region and a corresponding decrease in the interface passivation performance. In this application, a thicker alumina layer is formed in the first electrode region to enhance the passivation effect and effectively suppress carrier recombination loss.

[0021] In one implementation, the first passivation antireflection layer includes at least an aluminum oxide layer, wherein the peak concentration of antimony in the aluminum oxide layer located in the first electrode region is greater than the peak concentration of antimony in the aluminum oxide layer located in the first non-electrode region.

[0022] With the above technical solution, antimony enters the alumina layer through lattice substitution or interstitial doping. On the one hand, it acts as a strong hydrogen trap to bind hydrogen atoms, delaying the rapid evolution and accumulation of hydrogen during high-temperature processes and preventing hydrogen-induced bubbling. On the other hand, it regulates the lattice expansion of alumina, reducing the mismatch in its thermal expansion coefficient with the silicon substrate and releasing internal stress in the film. Simultaneously, antimony segregates at the silicon / alumina interface to form stable Sb-Si bonds and Sb-O-Al bridging bonds, strengthening the interfacial bonding force and passivating interfacial defects. Furthermore, the lattice distortion introduced by antimony doping can passivate microcracks and improve the toughness of the film, ultimately significantly reducing the risk of cracking and peeling of the alumina layer during high-temperature sintering and long-term service, while maintaining and optimizing the passivation performance of the alumina layer 30 on the first electrode region 10.

[0023] In one implementation, the peak concentration of antimony in the alumina layer located in the first electrode region ranges from 7 × 10⁻⁶. 16 atom / cm 3 Up to 5×10 18 atom / cm 3 ;

[0024] In one implementation, the peak concentration of antimony in the alumina layer located in the first non-electrode region ranges from 5 × 10⁻⁶. 16 atom / cm 3 Up to 4×10 18 atom / cm 3 .

[0025] In one implementation, the first non-electrode region includes a sidewall and a bottom surface, the sidewall being located between an adjacent first electrode region and the bottom surface, and the sidewall being inclined relative to the thickness direction of the semiconductor substrate. The first passivation antireflection layer includes at least an aluminum oxide layer, the thickness of the aluminum oxide layer on the sidewall being greater than the thickness of the aluminum oxide layer on the bottom surface, and / or, the thickness of the aluminum oxide layer on the sidewall being greater than the thickness of the aluminum oxide layer within the first electrode region.

[0026] With the above technical solution, the sidewalls are mostly etched transition regions with high interface defect state density, more dangling bonds, and a higher surface recombination rate compared to the first electrode region and the bottom surface. Therefore, increasing the thickness of the alumina layer on the sidewalls can significantly improve the interface passivation effect, effectively suppress surface carrier recombination, and increase minority carrier lifetime. For example, if the beveled surface of the sidewall has special structures such as holes or visors, the passivation requirements in this region are even higher. This application strengthens passivation by forming a thicker alumina layer.

[0027] Furthermore, because the sidewalls are inclined relative to the thickness direction of the semiconductor substrate, the tilt angle morphology can easily lead to thinner films, incomplete coverage, and uneven film deposition under the same deposition conditions. In this application, increasing the thickness of the alumina layer on the sidewalls ensures dense and continuous alumina coverage, avoids local film defects, and improves the formation quality of the alumina layer.

[0028] Furthermore, since the first electrode region and the bottom surface are flatter than the sidewalls, they have fewer defects and lower recombination rates. Therefore, a relatively thin alumina layer can be used in the first electrode region and the bottom surface to meet the passivation requirements, reducing manufacturing costs and light absorption loss.

[0029] In addition, the relatively thicker alumina layer has a stronger barrier effect, which can effectively block the diffusion and migration of electrode metal ions and impurities along the inclined interface, suppress edge leakage, improve open circuit voltage, and ensure the stability of solar cells.

[0030] In one implementation, the first passivation antireflection layer includes at least an aluminum oxide layer. The first surface includes a first intermediate region and a first edge region surrounding the first intermediate region. The thickness direction of the aluminum oxide layer located in the first intermediate region is aligned with the thickness direction of the semiconductor substrate. The thickness of the aluminum oxide layer located in at least a portion of the first edge region is greater than the thickness of the aluminum oxide layer located in the first intermediate region, and / or, the peak concentration of antimony in the aluminum oxide layer located in at least a portion of the first edge region is less than the peak concentration of antimony in the aluminum oxide layer located in the first intermediate region.

[0031] With the above technical solution, the antimony concentration in the first edge region is lower, which weakens the degree of lattice distortion, reduces the thermal expansion mismatch stress at the edge, and avoids blistering, peeling, and cracking defects in the edge film due to stress concentration, thereby improving the overall structural integrity of the passivation film. In particular, the alumina layer located in the first edge region is thicker, making it more prone to defects such as cracks.

[0032] In one implementation, the semiconductor substrate includes a second intermediate region and a second edge region surrounding the second intermediate region. The concentration of antimony in the semiconductor substrate located within the second intermediate region is greater than the concentration of antimony in the semiconductor substrate located in at least a portion of the second edge region, and the thickness direction of the semiconductor substrate located within the second intermediate region is aligned with the direction from the first surface to the second surface.

[0033] When the above technical solution is adopted, low antimony doping in the edge region can increase the resistivity of the edge doped layer, suppress edge impurity migration and band distortion, and reduce the edge recombination probability.

[0034] In one implementation, the semiconductor substrate includes a second intermediate region and a second edge region surrounding the second intermediate region. The thickness direction of the semiconductor substrate located within the second intermediate region is aligned with the directions of the two non-side-facing regions. The peak concentration of antimony in the film layer located within at least a portion of the second edge region and within the first electrode region is less than the peak concentration of antimony in the film layer located within at least a portion of the second intermediate region and within the first electrode region. And / or, the peak concentration of antimony in the film layer located within at least a portion of the second edge region and within the first non-electrode region is less than the peak concentration of antimony in the film layer located within at least a portion of the second intermediate region and within the first non-electrode region.

[0035] In one implementation, the solar cell further includes a contact transition layer. The contact transition layer is located in the first electrode region and between the first electrode and the first doped semiconductor layer, and contains antimony.

[0036] By employing the above technical solution, the bonding force between the first electrode and the first doped semiconductor layer can be enhanced, improving the quality of the solar cell. Furthermore, the antimony element located within the contact transition layer provides excellent lateral conductivity, and because the contact transition layer is close to the first electrode, it can effectively reduce contact resistance and promote the lateral transport of photogenerated carriers to the first electrode, improving carrier transport efficiency. Moreover, it can improve the crystallization state of the contact transition layer, alleviate interfacial stress, and enhance ohmic contact stability.

[0037] In one implementation, the contact transition layer comprises a metal oxide layer and / or a silicon oxide layer. The metal includes one or more of silver, copper, aluminum, nickel, lead, or bismuth.

[0038] In one implementation, the first electrode region includes a contact region and a non-contact region. The contact region is the area where the orthogonal projection of the first electrode onto the semiconductor substrate lies along the thickness direction of the semiconductor substrate. The peak concentration of antimony in the contact region is greater than the peak concentration of antimony in the non-contact region, and / or, the peak concentration of antimony in the first doped semiconductor layer located in the contact region is greater than the peak concentration of antimony in the first doped semiconductor layer located in the non-contact region.

[0039] When employing the above technical solution, since the region where the first electrode's orthogonal projection onto the semiconductor substrate is located is the contact region, when the peak concentration of antimony in the contact region or the peak concentration of antimony in the first doped semiconductor layer located in the contact region is relatively high, the contact resistance can be further reduced, the carrier transport efficiency improved, and the bonding force between the first electrode and the first doped semiconductor layer enhanced. Furthermore, when printing the paste forming the first electrode in the contact region, higher strength is required to reduce debris. In this application, since the peak concentration of antimony in the first doped semiconductor layer located in the contact region is greater than the peak concentration of antimony in the first doped semiconductor layer located in the non-contact region, the strength of the solar cell in the contact region can be increased to reduce or eliminate the probability of debris during the paste printing process.

[0040] In one implementation, the first surface further includes a second electrode region, with the first and second electrode regions arranged alternately, and a first non-electrode region located between the first and second electrode regions. The solar cell also includes a tunneling layer, a third doped semiconductor layer, and a second electrode. The tunneling layer is disposed on a semiconductor substrate and is located at least in the second electrode region. The third doped semiconductor layer, located in the second electrode region, is disposed on the side of the tunneling layer away from the semiconductor substrate, and the doping type of the third doped semiconductor layer is opposite to that of the first doped semiconductor layer. A first passivation antireflection layer is also formed on the third doped semiconductor layer, and the second electrode is located in the second electrode region, passing through the first passivation antireflection layer and connecting to the third doped semiconductor layer.

[0041] At this point, the aforementioned solar cell is a back-contact solar cell. Furthermore, the first non-electrode region can isolate the first doped semiconductor layer and the third doped semiconductor layer, reducing the carrier recombination rate at the lateral boundary between the first and third doped semiconductor layers, which is beneficial to improving the photoelectric conversion efficiency of the solar cell.

[0042] In one implementation, the second surface includes a third electrode region and a second non-electrode region alternately distributed along a first direction. The solar cell further includes a tunneling layer, a fourth doped semiconductor layer, a second passivation antireflection layer, and a third electrode. The tunneling layer is disposed on the semiconductor substrate and is located at least in the third electrode region. The fourth doped semiconductor layer, located in the third electrode region, is disposed on the side of the tunneling layer away from the semiconductor substrate. The doping type of the fourth doped semiconductor layer is opposite to that of the first doped semiconductor layer. The second passivation antireflection layer is located at least on the fourth doped semiconductor layer. The third electrode is located in the third electrode region and is connected to the fourth doped semiconductor layer through the second passivation antireflection layer.

[0043] Secondly, the present invention also provides a photovoltaic module. The photovoltaic module includes a cell string and an encapsulation layer. The cell string includes multiple interconnecting elements and multiple solar cells as described in the above-described technical solutions. The interconnecting elements connect the multiple solar cells in series, and the encapsulation layer covers the surface of the cell string.

[0044] The beneficial effects of the photovoltaic module provided by this invention are the same as those of the solar cell described in the above technical solution, and will not be repeated here. Attached Figure Description

[0045] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the structure of the first type of solar cell in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the second type of solar cell in an embodiment of the present invention; Figure 3 This is the antimony element concentration distribution curve in the first non-electrode region of this invention embodiment; Figure 4 This is a partial structural diagram of the semiconductor substrate in an embodiment of the present invention; Figure 5 This is a top view of the alumina layer in an embodiment of the present invention; Figure 6 This is a top view of the semiconductor substrate in an embodiment of the present invention; Figure 7 This is a schematic diagram of a portion of the structure of a solar cell in an embodiment of the present invention.

[0046] Figure label: 1-Semiconductor substrate, 10-First electrode region, 100-Contact region, 101-Non-contact region, 11-First non-electrode region, 111-Bottom surface, 12-Second intermediate region, 13-Second edge region; 2-First doped semiconductor layer; 3-First passivation antireflection layer, 30-Alumina layer, 300-First intermediate region, 301-First edge region, 31-Antireflection layer; 4-First electrode, 5-Sidewall, 7-Second electrode region, 8-Tunneling layer, 9-Third doped semiconductor layer, 90-Second electrode, 91-Third electrode region, 92-Second non-electrode region, 93-Fourth doped semiconductor layer, 94-Third electrode, 95-Second passivation antireflection layer. Detailed Implementation

[0047] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention.

[0048] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0049] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.

[0050] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0051] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0052] To address the aforementioned technical problems, in a first aspect, the present invention provides a solar cell. (See also...) Figure 1 and Figure 2 The solar cell includes: a semiconductor substrate 1, a first doped semiconductor layer 2, a second doped semiconductor layer, a first passivation antireflection layer 3, and a first electrode 4. Along the thickness direction A of the semiconductor substrate 1, the semiconductor substrate 1 includes a first surface and a second surface opposite to each other. The first surface includes a first electrode region 10 and a first non-electrode region 11. The first doped semiconductor layer 2 is located in the first electrode region 10, and the second doped semiconductor layer is located in the first non-electrode region 11; alternatively, the first doped semiconductor layer 2 is located in the first electrode region 10, and no doped semiconductor layer is disposed in the first non-electrode region. The first passivation antireflection layer 3 is disposed at least on the first doped semiconductor layer 2 and the second doped semiconductor layer. The first electrode 4 is located in the first electrode region 10, and the first electrode 4 passes through the first passivation antireflection layer 3 and is electrically connected to the first doped semiconductor layer 2.

[0053] In terms of shape, the first and second surfaces of the semiconductor substrate 1 may have the same or different shapes. In this embodiment of the invention, the first and second surfaces have the same shape. For example, the shape of the first or second surface may be a square, a rectangle, a rounded square, a circle, etc.

[0054] In terms of materials, the semiconductor substrate 1 can be any semiconductor material such as silicon substrate, germanium silicon substrate, germanium substrate or gallium arsenide substrate.

[0055] In terms of conductivity type, the semiconductor substrate 1 can be an intrinsically conductive substrate, an N-type conductive substrate, or a P-type conductive substrate. Preferably, the semiconductor substrate 1 is a P-type conductive substrate or an N-type conductive substrate. Compared with an intrinsically conductive substrate, a P-type conductive substrate or an N-type conductive substrate has better conductivity, resulting in a lower bulk resistivity in the final solar cell and thus improving the efficiency of the solar cell. For example, the semiconductor substrate 1 is an N-type silicon substrate. Compared with a P-type conductive substrate, an N-type silicon substrate has advantages such as higher minority carrier lifetime, no light decay, and better performance in low-light conditions.

[0056] In terms of light reception, if the first side is the light-facing side, then the second side is the shadow-facing side. Alternatively, if the first side is the shadow-facing side, then the second side is the light-facing side.

[0057] In some embodiments, the first surface is the light-facing surface and the second surface is the backlight surface.

[0058] As one possible implementation, the doping concentration of the first doped semiconductor layer 2 is greater than the doping concentration of the second doped semiconductor layer.

[0059] With the above technical solution, the doping concentration of the first doped semiconductor layer 2 disposed in the first electrode region 10 is greater than the doping concentration of the second doped semiconductor layer disposed in the first non-electrode region 11. By reducing the doping concentration of the first non-electrode region 11, the high-concentration area on the first surface of the solar cell is reduced, the recombination problem caused by the high doping concentration on the surface of the semiconductor substrate 1 is reduced, and the open-circuit voltage of the cell is increased. At the same time, the first doped semiconductor layer 2 with a higher doping concentration is disposed in the first electrode region 10 to ensure that there is a smaller contact resistance between the first electrode 4 and the first doped semiconductor layer 2, reduce the series resistance of the cell, improve the fill factor, and thus improve the efficiency of the solar cell.

[0060] In one alternative approach, see Figure 1 and Figure 2 The first doped semiconductor layer 2 is disposed only in the first electrode region 10, while the second doped semiconductor layer is not disposed in the first non-electrode region 11. A PN junction is formed between the semiconductor substrate 1 and the first doped semiconductor layer 2 located in the first electrode region 10, while no PN junction exists in the first non-electrode region 11 of the semiconductor substrate 1. That is, the first surface of the solar cell includes a heavily doped region and an undoped region. This effectively reduces the recombination level in the first non-electrode region 11 of the first surface, increases the open-circuit voltage of the cell, and improves the minority carrier lifetime. Simultaneously, high doping can be performed in the first electrode region 10, improving the contact resistance between the electrode and the first doped semiconductor layer 2, reducing the series resistance of the cell, and increasing the fill factor, thereby improving the efficiency of the solar cell.

[0061] Furthermore, the aforementioned "doping concentration of the first doped semiconductor layer 2" may refer to the doping concentration on the surface of the first doped semiconductor layer 2, or to the average concentration at different locations along the thickness direction of the first doped semiconductor layer 2.

[0062] Similarly, "doping concentration of the second doped semiconductor layer" can refer to the doping concentration on the surface of the second doped semiconductor layer, or the average concentration at different locations along the thickness direction of the second doped semiconductor layer.

[0063] "The doping concentration of the first doped semiconductor layer 2 is greater than the doping concentration of the second doped semiconductor layer" can mean that the doping concentration on the surface of the first doped semiconductor layer 2 is greater than the doping concentration on the surface of the second doped semiconductor layer. Alternatively, it can mean that the average concentration of the first doped semiconductor layer 2 at different locations along the thickness direction is greater than the average concentration of the second doped semiconductor layer at different locations along the thickness direction.

[0064] In some embodiments, see Figure 1 and Figure 2 The first doped semiconductor layer 2 may be an additional film layer formed on the semiconductor substrate 1. Alternatively, the first doped semiconductor layer 2 may be formed by diffusion treatment on the first surface of the semiconductor substrate 1, in which case the top surface of the first doped semiconductor layer 2 is coplanar with the first surface of the semiconductor substrate 1.

[0065] In some embodiments, see Figure 1 and Figure 2 The second doped semiconductor layer can be an additional film layer formed on the semiconductor substrate 1. Alternatively, the second doped semiconductor layer can be formed by diffusion treatment on the first surface of the semiconductor substrate 1, in which case the top surface of the second doped semiconductor layer is coplanar with the first surface of the semiconductor substrate 1.

[0066] In one alternative approach, the doping depth of the doped element in the first electrode region 10 is greater than the doping depth of the doped element in the first non-electrode region 11. Alternatively, the sheet resistance of the first doped semiconductor layer 2 is less than the sheet resistance of the second doped semiconductor layer. In this case, the overall passivation level of the solar cell can be improved, the cell's turn-on voltage can be increased, and the cell efficiency can be enhanced.

[0067] In some embodiments, the first doped semiconductor layer 2 and the second doped semiconductor layer can be formed by doping with boron.

[0068] As one possible implementation, see Figure 1 and Figure 2 The semiconductor substrate 1 is an N-type silicon substrate, the first doped semiconductor layer 2 is a P-type doped layer, and the second doped semiconductor layer is a P-type doped layer. Both the first and second doped semiconductor layers are diffusion layers on the surface of the semiconductor substrate 1. In this case, the surfaces of the first and second doped semiconductor layers are single-crystal silicon surfaces. Setting the doping concentration of the second doped semiconductor layer to be lower than that of the first doped semiconductor layer 2 is more important than adding additional doped semiconductor layers to improve the passivation of the semiconductor substrate 1 surface by the subsequent first passivation and antireflection layer 3.

[0069] As one possible implementation, the semiconductor substrate 1 is doped with antimony, and the first doped semiconductor layer 2, the second doped semiconductor layer, and the first passivation antireflection layer 3 all contain antimony.

[0070] It is understandable that, such as Figure 1 As shown, the first electrode region 10 and the first non-electrode region 11 can be distinguished by a height difference. This height difference typically stems from different process steps during manufacturing, such as selective etching, material deposition, or removal, resulting in step-like or undulating morphological features on the first surface. The areas defined by the first electrode region 10 and the first non-electrode region 11 are not limited to the two-dimensional plane containing the first surface, but also include spatial portions of a certain depth extending downward or upward along the thickness direction A. In the above technical solution, the semiconductor substrate 1, the first doped semiconductor layer 2, and the second doped semiconductor layer contain antimony. The distribution of antimony helps to reduce the resistivity, improve the conductivity of the first electrode region, and reduce the transport loss of charge carriers in the first non-electrode region due to the reduced doping concentration. The first passivation antireflection layer 3 contains antimony, which can reduce the film bursting phenomenon of the passivation layer and improve the chemical passivation performance of the passivation layer, thereby enhancing the passivation capability of the first passivation antireflection layer 3. The steric hindrance effect caused by the lattice distortion resulting from the antimony element in the first doped semiconductor layer 2 and the first passivation antireflection layer 3 can effectively hinder or suppress the diffusion and accumulation of transition metal impurities such as Fe and Cu in the first electrode within the aforementioned film layers, thus preventing the diffusion of metal elements in the first electrode. Furthermore, since the first non-electrode region 11 is not obstructed by the grid lines, it focuses on balancing the light-trapping effect and passivation performance of the first surface of the battery cell, while the first electrode region 10 focuses on balancing contact performance and passivation performance.

[0071] As one possible implementation, the first electrode 4 may contain antimony.

[0072] As one possible implementation, within the first electrode region 10, the maximum peak concentration of antimony in the first doped semiconductor layer 2, the first passivation antireflection layer 3, and the first electrode 4 is n1. Within the first non-electrode region 11, the maximum peak concentration of antimony in the second doped semiconductor layer and the first passivation antireflection layer 3 is n2. Wherein, n1 is greater than n2. It should be noted that peak concentration refers to the maximum concentration value of antimony. The values ​​of n1 and n2 range from 5 × 10⁻⁶. 13 atoms / cm 3 -1×10 16 atoms / cm 3 Preferably, the values ​​of n1 and n2 are in the range of 5 × 10⁻⁶. 14 atoms / cm 3 -1×10 15 atoms / cm 3 .

[0073] In the above technical solution, the first electrode region 10 is provided with a first doped semiconductor layer 2 with a higher doping concentration and a first electrode. The first electrode region 10 needs to balance the contact performance and passivation performance between the first electrode and the first doped semiconductor layer 2. This arrangement can improve the conductivity of the first doped semiconductor layer 2 and enhance the contact performance between the first electrode 4 and the first doped semiconductor layer 2. At the same time, the antimony element enhances the passivation performance of the first passivation antireflection layer 3 and the diffusion blocking effect on metal elements, thus balancing the transport performance and passivation performance of the first electrode region 10. Furthermore, although the doping concentration of the second doped semiconductor layer in the first non-electrode region 11 is relatively small, or the first non-electrode region 11 does not have a doped semiconductor layer, reducing the recombination problem caused by high doping concentration, it also reduces the lateral transport capability of charge carriers in the first non-electrode region 11. The antimony element can reduce the resistivity of the semiconductor substrate, reduce the transport loss of charge carriers in the first non-electrode region 11, and further improve the passivation of the surface of the first non-electrode region 11.

[0074] In summary, the structural configuration of the first electrode region 10 and the first non-electrode region 11 on the first surface, combined with the differentiated setting of antimony element concentration in the two regions, can improve the passivation performance of the first surface of the solar cell while satisfying its transmission performance, thereby further improving the open-circuit voltage and the final cell efficiency.

[0075] One possible implementation is to set a difference between the maximum peak concentration of antimony in the first doped semiconductor layer 2, the first passivation antireflection layer 3, and the first electrode 4 within the first electrode region 10, and the maximum peak concentration of antimony in the second doped semiconductor layer and the first passivation antireflection layer 3 within the first non-electrode region 11. This difference can be achieved by controlling the difference in specific surface area and the doped semiconductor layer configuration between the first electrode region 10 and the first non-electrode region 11, thereby synergistically controlling the thickness difference of the surface film in both regions, ultimately realizing a difference in antimony concentration between the two regions. For example, by preparing textured structures in the first electrode region 10 and the first non-electrode region 11 at different steps, and adjusting process parameters such as solution temperature, etching time, and additive differences during the etching process, textured structures with different sizes and undulations can be formed in the two regions. Regions with smaller texture undulations have smaller effective specific surface areas, resulting in larger subsequent film thicknesses and consequently higher peak antimony concentrations within the film.

[0076] As one possible implementation, see Figure 1 The surface of the first electrode region 10 has a first texture structure, and the first non-electrode region 11 has a second texture structure.

[0077] In one alternative approach, see Figure 1The first texture structure and / or the second texture structure are pyramidal or pyramid-like structures. This is beneficial for increasing the surface area of ​​the semiconductor substrate 1, improving the light-trapping effect of the semiconductor substrate 1, and allowing more light to be refracted into the semiconductor substrate 1 through the area where the first texture structure and / or the second texture structure are located, thus enabling the solar cell to have a higher photoelectric conversion efficiency. In addition, the pyramidal or pyramid-like structure with a larger roughness can also reduce the film bursting phenomenon in the passivation layer, further ensuring the passivation performance of the first electrode region 10 and the first non-electrode region 11.

[0078] In one alternative approach, see Figure 1 When the first texture structure is a pyramid-shaped structure, the height of the first texture structure is greater than or equal to 0.5 μm and less than or equal to 4 μm, and the base dimension of the first texture structure is greater than or equal to 0.5 μm and less than or equal to 5 μm. The base of the first texture structure can be square, rhomboid, rectangular, parallelogram, approximately rhomboid, or approximately rectangular. The base dimension of the first texture structure can be the long side, short side, diagonal, or the farthest distance between the two endpoints of the base shape. The height and base dimension of the first texture structure can be the height or base dimension of a single texture structure, or it can be the average value of the height or base dimension of the first texture structure within a certain area. For example, within a range of 1 μm × 1 μm, the height of the first texture structure can be 0.5 μm, 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, or 4 μm, etc. The bottom surface dimensions of the first texture structure can be 0.5μm, 1μm, 1.5μm, 2μm, 2.5μm, 3μm, 3.5μm, 4μm, 4.5μm, or 5μm, etc.

[0079] In one alternative approach, see Figure 1 When the second texture structure is a pyramid-shaped structure, the height of the second texture structure is greater than or equal to 0.5 μm and less than or equal to 4 μm, and the base dimension of the second texture structure is greater than or equal to 0.5 μm and less than or equal to 5 μm. The base of the second texture structure can be square, rhomboid, rectangular, parallelogram, approximately rhomboid, or approximately rectangular. The base dimension of the second texture structure can be the long side, short side, diagonal, or the farthest distance between the two endpoints of the base shape. The height and base dimension of the second texture structure can be the height or base dimension of a single texture structure, or it can be the average value of the height or base dimension of the second texture structures within a certain area. For example, within a range of 1 μm × 1 μm, the height of the second texture structure can be 0.5 μm, 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, or 4 μm, etc. The bottom surface dimensions of the second texture structure can be 0.5μm, 1μm, 1.5μm, 2μm, 2.5μm, 3μm, 3.5μm, 4μm, 4.5μm, or 5μm, etc.

[0080] See Figure 1 The tower height or base dimensions of the first and second texture structures can be equal or unequal.

[0081] As one possible implementation, the first electrode region 10 and the first non-electrode region 11 are alternately distributed.

[0082] As one possible implementation, the first electrode region 10 and the first non-electrode region 11 have a height difference. In this case, light can be reflected and absorbed within the groove to reduce reflectivity.

[0083] In one alternative approach, along the thickness direction A of the semiconductor substrate 1, the first electrode region 10 is higher than the first non-electrode region 11.

[0084] For example, along the thickness direction of the semiconductor substrate 1, the distance L1 between the first electrode region 10 and the first non-electrode region 11 is greater than or equal to 0.5 μm and less than or equal to 6 μm. In this case, the first non-electrode region 11 is recessed relative to the first electrode region 10, so that light can be reflected and absorbed within the recess, thereby reducing the reflectivity of the second textured structure.

[0085] See Figure 1 The distance L1 between the first electrode region 10 and the first non-electrode region 11 can be the distance between the top surface of the first electrode region 10 and the top surface of the first non-electrode region 11, or the distance between the bottom surface of the first electrode region 10 and the bottom surface of the first non-electrode region 11, or the distance between the bottom surface of the first electrode region 10 and the top surface of the first non-electrode region 11, or the distance between the top surface of the first electrode region 10 and the bottom surface of the first non-electrode region 11. For example, the distance L1 between the top surface of the first electrode region 10 and the top surface of the first non-electrode region 11 can be 0.5μm, 1μm, 1.5μm, 2μm, 2.5μm, 3μm, 3.5μm, 4μm, 4.5μm, 5μm, 5.5μm, or 6μm, etc.

[0086] It is worth noting that, see Figure 1 The top surface of the first electrode region 10 is composed of vertices of multiple first texture structures. Since the sizes of different first texture structures vary, the top surface here is a plane composed of the vertices of most of the first texture structures on the first electrode region 10. The proportion of most of the first texture structures in the first electrode region 10 can be flexibly selected according to the actual situation. Similarly, the top surface of the first non-electrode region 11 is composed of vertices of multiple second texture structures.

[0087] See Figure 1 and Figure 2The first passivation antireflection layer 3 can be a single-layer structure or a stacked structure composed of multiple film layers. For example, the first passivation antireflection layer 3 can include a passivation layer and an antireflection layer 31. The passivation layer can be an aluminum oxide layer 30, and the antireflection layer 31 can include at least one or more layers of silicon nitride, silicon oxynitride, or titanium oxide.

[0088] For example, the first passivation antireflection layer 3 may consist only of the aluminum oxide layer 30. Alternatively, the first passivation antireflection layer 3 may be a stacked structure of silicon nitride and aluminum oxide; or a stacked structure of silicon oxynitride and aluminum oxide; or a stacked structure of silicon nitride, silicon oxynitride and aluminum oxide; or a stacked structure of aluminum oxide and titanium oxide; or a stacked structure of silicon oxide and titanium oxide.

[0089] As one possible implementation, see Figures 1 to 3 The first passivation antireflection layer 3 includes at least an aluminum oxide layer 30. Within the first non-electrode region 11, the peak concentration of antimony in the second doped semiconductor layer and the peak concentration of antimony in the semiconductor substrate 1 are both lower than the peak concentration of antimony in the aluminum oxide layer 30. It should be noted that... Figure 3 This represents the antimony concentration distribution in the first non-electrode region 11. The dashed line indicates the peak antimony concentration position in the alumina layer 30. Because the elemental distribution may be affected by instrument measurements during the test, the width range of the curve does not correspond one-to-one with the actual concentration distribution range. For example... Figure 3 In this context, the unit for antimony concentration can be atom / cm³. 3 The unit of depth can be μm. Within the first electrode region 10, the peak concentration of antimony in the first doped semiconductor layer 2 and the peak concentration of antimony in the semiconductor substrate 1 are both lower than the peak concentration of antimony in the alumina layer 30.

[0090] With the above technical solution, antimony enters the alumina layer through lattice substitution or interstitial doping. On the one hand, it acts as a strong hydrogen trap to bind hydrogen atoms, delaying the rapid evolution and accumulation of hydrogen during high-temperature processes and preventing hydrogen-induced blistering. On the other hand, it regulates the lattice expansion of alumina, reducing the mismatch in its thermal expansion coefficient with the silicon substrate and releasing internal stress in the film. Simultaneously, antimony segregates at the silicon / alumina interface to form stable Sb-Si and Sb-O-Al bridging bonds, strengthening the interfacial bonding and passivating interfacial defects. Furthermore, the lattice distortion introduced by antimony doping can passivate microcracks and improve the toughness of the film, ultimately significantly reducing the risk of cracking and peeling of the alumina layer during high-temperature sintering and long-term service, while maintaining and optimizing its passivation performance.

[0091] As another possible implementation, see Figure 1 and Figure 2The first passivation antireflection layer 3 includes an aluminum oxide layer 30 and an antireflection layer 31. The aluminum oxide layer 30 is disposed on the first doped semiconductor layer 2 and the second doped semiconductor layer, and the antireflection layer 31 is disposed on the side of the aluminum oxide layer 30 facing away from the semiconductor substrate 1. In the first non-electrode region 11, the distance between the side of the antireflection layer 31 facing away from the semiconductor substrate 1 and the location of the peak concentration of antimony in the aluminum oxide layer 30 is a first distance. In the first electrode region 10, the distance between the side of the antireflection layer 31 facing away from the semiconductor substrate 1 and the location of the peak concentration of antimony in the aluminum oxide layer 30 is a second distance. The directions of the first distance and the second distance are both consistent with the thickness direction of the semiconductor substrate 1. The first distance is less than the second distance, and / or the value of the first distance ranges from 60 nm to 150 nm, and / or the value of the second distance ranges from 80 nm to 180 nm.

[0092] With the above technical solution, the distribution of antimony in the first electrode region 10 in the first passivation antireflection layer 3 is closer to the surface of the silicon substrate, which is more conducive to the segregation of antimony at the silicon / alumina interface to form stable Sb-Si bonds and Sb-O-Al bridge bonds, thereby strengthening the interface bonding force and passivating interface defects.

[0093] For example, the first distance can be 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, or 150nm, etc. The second distance can be 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, 150nm, 160nm, 170nm, or 180nm, etc.

[0094] As one possible implementation, see Figure 1 and Figure 2 The peak concentration of antimony in the first doped semiconductor layer 2 located in the first electrode region 10 is greater than the peak concentration of antimony in the second doped semiconductor layer located in the first non-electrode region 11.

[0095] When the above technical solution is adopted, antimony can reduce the resistivity in the doped semiconductor layer and improve the conductivity of the first doped semiconductor layer 2. Furthermore, setting a higher concentration of antimony in the first doped semiconductor layer 2 is beneficial to enhancing the contact performance between the first electrode 4 and the first doped semiconductor layer 2.

[0096] For example, the element doped in the first doped semiconductor layer 2 and the second doped semiconductor layer is boron.

[0097] In one alternative approach, see Figure 1 and Figure 2The peak concentration of antimony in the first doped semiconductor layer 2 located within the first electrode region 10 ranges from 2 × 10⁻⁶. 15 atom / cm 3 Up to 2×10 18 atom / cm 3 .

[0098] When the peak concentration of antimony is less than 2×10 15 atom / cm 3 When the concentration of antimony is greater than 2 × 10⁻⁶, its effect on reducing the resistivity of the first doped semiconductor layer 2 is relatively weak, thus affecting the conductivity of the first doped semiconductor layer 2. 18 atom / cm 3 If the lattice distortion of the first doped semiconductor layer 2 is too large, it will reduce the passivation performance of the first doped semiconductor layer 2. Based on this, this application sets the peak concentration of antimony in the first doped semiconductor layer 2 located in the first electrode region 10 within the above-mentioned range, thus balancing the conductivity and passivation performance of the first doped semiconductor layer 2.

[0099] For example, the peak concentration of antimony in the first doped semiconductor layer 2 located within the first electrode region 10 can be 2 × 10⁻⁶. 15 atom / cm 3 10×10 15 atom / cm 3 50×10 15 atom / cm 3 100×10 15 atom / cm 3 200×10 15 atom / cm 3 400×10 15 atom / cm 3 600×10 15 atom / cm 3 800×10 15 atom / cm 3 1000×10 15 atom / cm 3 1300×10 15 atom / cm 3 1500×10 15 atom / cm 3 1800×10 15 atom / cm 3 Or 2×10 18 atom / cm 3 wait.

[0100] As one possible implementation, see Figure 1 and Figure 2 The peak concentration of antimony in the second doped semiconductor layer located within the first non-electrode region 11 ranges from 1 × 10⁻⁶. 15 atom / cm 3 Up to 1×10 18 atom / cm 3 .

[0101] For example, the peak concentration of antimony in the second doped semiconductor layer located within the first non-electrode region 11 can be 1 × 10⁻⁶. 15 atom / cm 3 3×10 15 atom / cm 3 10×10 15 atom / cm 3 30×10 15 atom / cm 3 50×10 15 atom / cm 3 80×10 15 atom / cm 3 100×10 15 atom / cm 3 120×10 15 atom / cm 3 150×10 15 atom / cm 3 200×10 15 atom / cm 3 250×10 15 atom / cm 3 300×10 15 atom / cm 3 400×10 15 atom / cm 3 500×10 15 atom / cm 3 600×10 15 atom / cm 3 700×10 15 atom / cm 3 800×10 15 atom / cm 3 900×10 15 atom / cm 3 Or 1×10 18 atom / cm 3 wait.

[0102] As one possible implementation, see Figure 1 and Figure 2 The first passivation antireflection layer 3 includes at least an aluminum oxide layer 30, and the thickness of the aluminum oxide layer 30 located in the first electrode region 10 is greater than the thickness of the aluminum oxide layer 30 located in the first non-electrode region 11.

[0103] When using the above technical solution, the doping concentration of the first doped semiconductor layer 2 at the first electrode region 10 is higher than that of the second doped semiconductor layer at the first non-electrode region 11, resulting in an enhanced recombination effect in the first electrode region 10 and a corresponding decrease in the interface passivation performance. In this application, a thicker alumina layer 30 is formed in the first electrode region 10 to enhance the passivation effect and effectively suppress carrier recombination loss.

[0104] As one possible implementation, see Figure 1 and Figure 2 The first passivation antireflection layer 3 includes at least an aluminum oxide layer 30, and the peak concentration of antimony in the aluminum oxide layer 30 located in the first electrode region 10 is greater than the peak concentration of antimony in the aluminum oxide layer 30 located in the first non-electrode region 11.

[0105] With the above technical solution, antimony enters the alumina layer through lattice substitution or interstitial doping. On the one hand, it acts as a strong hydrogen trap to bind hydrogen atoms, delaying the rapid evolution and accumulation of hydrogen during high-temperature processes and preventing hydrogen-induced bubbling. On the other hand, it regulates the lattice expansion of alumina, reducing the mismatch in its thermal expansion coefficient with the silicon substrate and releasing internal stress in the film. Simultaneously, antimony segregates at the silicon / alumina interface to form stable Sb-Si bonds and Sb-O-Al bridging bonds, strengthening the interfacial bonding force and passivating interfacial defects. Furthermore, the lattice distortion introduced by antimony doping can passivate microcracks and improve the toughness of the film, ultimately significantly reducing the risk of cracking and peeling of the alumina layer during high-temperature sintering and long-term service, while maintaining and optimizing the passivation performance of the alumina layer 30 on the first electrode region 10.

[0106] In some embodiments, the thickness of the alumina layer 30 located in the first electrode region 10 is greater than the thickness of the alumina layer 30 located in the first non-electrode region 11, and the peak concentration of antimony in the alumina layer 30 located in the first electrode region 10 is greater than the peak concentration of antimony in the alumina layer 30 located in the first non-electrode region 11.

[0107] Because the alumina layer 30 located in the first electrode region 10 is relatively thicker, it is more prone to film bursting or cracking compared to the alumina layer 30 located in the first non-electrode region 11. However, since the peak concentration of antimony in the alumina layer 30 located in the first electrode region 10 is greater than that in the alumina layer 30 located in the first non-electrode region 11, increasing the concentration of antimony in the alumina layer 30 located in the first electrode region 10 strengthens its strength and improves its quality.

[0108] As one possible implementation, see Figure 1 and Figure 2 The peak concentration of antimony in the alumina layer 30 located in the first electrode region 10 ranges from 7 × 10⁻⁶. 16 atom / cm 3 Up to 5×10 18 atom / cm 3 .

[0109] For example, the peak concentration of antimony in the alumina layer 30 located in the first electrode region 10 can be 7 × 10⁻⁶. 16 atom / cm 3 10×10 16 atom / cm 3 30×10 16 atom / cm 3 50×10 16 atom / cm 3 80×10 16 atom / cm 3 100×10 16 atom / cm 3 150×10 16 atom / cm 3 200×10 16 atom / cm 3 250×10 16 atom / cm 3 300×10 16 atom / cm 3 350×10 16 atom / cm 3 400×10 16 atom / cm 3 Or 5×10 18 atom / cm 3 wait.

[0110] As one possible implementation, the peak concentration of antimony in the alumina layer 30 located in the first non-electrode region 11 ranges from 5 × 10⁻⁶. 16 atom / cm 3 Up to 4×10 18 atom / cm 3 .

[0111] For example, the peak concentration of antimony in the alumina layer 30 located in the first non-electrode region 11 can be 5 × 10⁻⁶. 16 atom / cm 3 10×10 16 atom / cm 3 30×10 16 atom / cm 3 50×10 16 atom / cm 3 80×10 16 atom / cm 3 100×10 16 atom / cm 3 150×10 16 atom / cm 3 200×10 16 atom / cm 3 250×10 16 atom / cm 3 300×10 16 atom / cm 3 350×10 16 atom / cm 3 380×10 16 atom / cm 3 Or 4×10 18 atom / cm 3 wait.

[0112] As one possible implementation, see Figures 1 to 4 The first non-electrode region 11 includes a sidewall 5 and a bottom surface 111. The sidewall 5 is located between the adjacent first electrode region 10 and the bottom surface 111, and the sidewall 5 is inclined relative to the thickness direction of the semiconductor substrate 1. The first passivation antireflection layer 3 includes at least an aluminum oxide layer 30. The thickness of the aluminum oxide layer 30 on the sidewall 5 is greater than the thickness of the aluminum oxide layer 30 on the bottom surface 111, and / or, the thickness of the aluminum oxide layer 30 on the sidewall 5 is greater than the thickness of the aluminum oxide layer 30 located in the first electrode region 10.

[0113] With the above technical solution, the sidewall 5 is mostly an etched transition region with a high interface defect state density, more dangling bonds, and a higher surface recombination rate compared to the first electrode region 10 and the bottom surface 111. Therefore, increasing the thickness of the alumina layer 30 on the sidewall 5 can significantly improve the interface passivation effect, effectively suppress surface carrier recombination, and improve minority carrier lifetime. For example, the slope of the sidewall 5 has special structures such as holes or visors, and this region has higher passivation requirements. This application can enhance passivation by forming a thicker alumina layer 30. Furthermore, since the sidewall 5 is inclined relative to the thickness direction of the semiconductor substrate 1, the slope angle morphology can easily lead to thinner film, incomplete coverage, and uneven film deposition under the same deposition conditions. In this application, increasing the thickness of the alumina layer 30 on the sidewall 5 can ensure dense and continuous coverage of the alumina layer 30, avoid local film defects, and improve the formation quality of the alumina layer 30. Furthermore, since the first electrode region 10 and the bottom surface 111 are flatter than the sidewall 5, they have fewer defects and lower recombination rates. Therefore, a relatively thin alumina layer 30 is sufficient to meet the passivation requirements for the first electrode region 10 and the bottom surface 111, reducing manufacturing costs and light absorption loss. In addition, a relatively thicker alumina layer 30 has stronger barrier properties, effectively preventing electrode metal ions and impurities from diffusing and migrating along the inclined interface, suppressing edge leakage, increasing open-circuit voltage, and ensuring the stability of the solar cell.

[0114] In one alternative approach, see Figures 1 to 4 The peak concentration of antimony in the alumina layer 30 located on the sidewall 5 is greater than the peak concentration of antimony in the alumina layer 30 located on the bottom surface 111.

[0115] At this point, the strength of the alumina layer 30 on the sidewall 5 can be enhanced, reducing or eliminating the probability of film bursting and cracking of the alumina layer 30 on the sidewall 5, thereby improving the passivation effect of the alumina layer 30 on the sidewall 5, reducing the carrier recombination rate on the surface of the solar cell located on the sidewall 5, and thus improving the photoelectric conversion efficiency of the solar cell. Furthermore, since the sidewall 5 is located between the first electrode region 10 and the bottom surface 111, the sidewall 5, as an intermediate sidewall, is more prone to fracture or microcracks. More antimony can increase the stress at the slope and reduce the fragmentation rate.

[0116] The thickness of the alumina layer 30 located at various positions on the side wall 5 can be set according to the actual situation, and no specific limitation is made here.

[0117] In one alternative, the thickness of the alumina layer 30 at various locations on the sidewall 5 is approximately equal.

[0118] In another alternative embodiment, the sidewall 5 includes a third intermediate region and end regions located on both sides of the third intermediate region, wherein the thickness of the alumina layer 30 in the end regions is greater than the thickness of the alumina layer 30 in the third intermediate region.

[0119] Since defects such as holes or brims are more likely to occur in the end area, the thickness of the alumina layer 30 located in the end area needs to be further increased to enhance passivation.

[0120] In one alternative embodiment, the peak concentration of antimony in the alumina layer 30 located in the end region is greater than the peak concentration of antimony in the alumina layer 30 located in the third intermediate region.

[0121] As one possible implementation, see Figure 5 The first passivation antireflection layer 3 includes at least an aluminum oxide layer 30. The first surface includes a first intermediate region 300 and a first edge region 301 surrounding the first intermediate region 300. The thickness direction of the aluminum oxide layer 30 on the first intermediate region 300 is consistent with the thickness direction of the semiconductor substrate 1. The thickness of the aluminum oxide layer 30 on at least a portion of the first edge region 301 is greater than the thickness of the aluminum oxide layer 30 on the first intermediate region 300, and / or, the peak concentration of antimony in the aluminum oxide layer 30 on at least a portion of the first edge region 301 is less than the peak concentration of antimony in the aluminum oxide layer 30 on the first intermediate region 300.

[0122] With the above technical solution, the antimony concentration in the first edge region 301 is lower, which weakens the degree of lattice distortion, reduces the thermal expansion mismatch stress at the edge, and avoids blistering, peeling, and cracking defects in the edge film due to stress concentration, thereby improving the overall structural integrity of the passivation film. In particular, the aluminum oxide layer 30 located in the first edge region 301 is thicker, making it more prone to defects such as cracks.

[0123] In some embodiments, the first edge region 301 extends from the edge of the first surface to the center of the solar cell by 1 μm to 5 μm.

[0124] In some embodiments, there is a difference between the thickness of the alumina layer 30 located in the first edge region 301 and the thickness of the alumina layer 30 located in the first intermediate region 300, and the ratio of the difference to the thickness of the alumina layer 30 located in the first intermediate region 300 is in the range of 2%-10%.

[0125] As one possible implementation, see Figure 6 The semiconductor substrate 1 includes a second intermediate region 12 and a second edge region 13 surrounding the second intermediate region 12. The thickness direction of the semiconductor substrate 1 located in the second intermediate region 12 is consistent with the direction from the first surface to the second surface.

[0126] In one alternative, the concentration of antimony in the semiconductor substrate 1 located in the second intermediate region 12 is greater than the concentration of antimony in the semiconductor substrate 1 located in at least a portion of the second edge region 13.

[0127] In one alternative approach, see Figure 6 The peak concentration of antimony in the film layer located within at least a portion of the second edge region 13 and within the first electrode region 10 is less than the peak concentration of antimony in the film layer located within at least a portion of the second intermediate region 12 and within the first electrode region 10. And / or, the peak concentration of antimony in the film layer located within at least a portion of the second edge region 13 and within the first non-electrode region 11 is less than the peak concentration of antimony in the film layer located within at least a portion of the second intermediate region 12 and within the first non-electrode region 11.

[0128] When the above technical solution is adopted, low antimony doping in the edge region can increase the resistivity of the edge doped layer, suppress edge impurity migration and band distortion, and reduce the edge recombination probability.

[0129] The following describes two possible scenarios: "The peak concentration of antimony in the film layer located in at least part of the second edge region 13 and on the first electrode region 10 is less than the peak concentration of antimony in the film layer located in at least part of the second intermediate region 12 and on the first electrode region 10." It should be noted that the following description is for understanding purposes only and is not intended to be specific.

[0130] The first type: When the solar cell is a whole solar cell, the peak concentration of antimony in the film layer located in all the second edge regions 13 and in the first electrode region 10 is less than the peak concentration of antimony in the film layer located in all the second middle regions 12 and in the first electrode region 10.

[0131] The second method involves cutting a single solar cell into segments. Before cutting, the single solar cell includes at least two electrode units spaced apart in a third direction, parallel to the first direction B. Adjacent electrode units are separated by a partition region extending along a fourth direction, perpendicular to the third direction. Cutting is then performed within this partition region along the fourth direction to obtain at least two segmented solar cells.

[0132] One possible example is that, for a slab solar cell, the peak concentration of antimony in the film layer located in the other second edge region 13 and within the first electrode region 10, excluding the original region belonging to the separator region and the edge region adjacent to the separator region, is lower than the peak concentration of antimony in the film layer located in the second intermediate region 12 and within the first electrode region 10.

[0133] The peak concentration of antimony in the film layer located in at least part of the second edge region 13 and in the first non-electrode region 11 is less than that in the film layer located in at least part of the second intermediate region 12 and in the first non-electrode region 11. Similarly, the peak concentration of antimony in the film layer located in at least part of the second intermediate region 12 and in the first non-electrode region 11 will not be described in detail here.

[0134] As one possible implementation, see Figure 7 The solar cell also includes a contact transition layer. The contact transition layer is located in the first electrode region 10 and between the first electrode 4 and the first doped semiconductor layer 2, and contains antimony.

[0135] This enhances the bonding force between the first electrode 4 and the first doped semiconductor layer 2, improving the quality of the solar cell. Furthermore, the antimony element located within the contact transition layer provides excellent lateral conductivity, and because the contact transition layer is close to the first electrode 4, it effectively reduces contact resistance and promotes the lateral transport of photogenerated carriers to the first electrode 4, improving carrier transport efficiency. Moreover, it can improve the crystallization state of the contact transition layer, alleviate interfacial stress, and enhance ohmic contact stability.

[0136] In some embodiments, the contact transition layer may be an alloy layer formed at the electrical connection between the first electrode 4 and the first doped semiconductor layer 2. The material included in the contact transition layer may be the material used to fabricate the first electrode 4.

[0137] In one alternative approach, see Figure 7 The contact transition layer comprises a metal oxide layer and / or a silicon oxide layer. The metal includes one or more of silver, copper, aluminum, nickel, lead, or bismuth.

[0138] For example, the contact transition layer includes oxygen, silicon, and metal.

[0139] As one possible implementation, see Figure 7 The first electrode region 10 includes a contact region 100 and a non-contact region 101. Along the thickness direction of the semiconductor substrate 1, the region where the orthogonal projection of the first electrode 4 onto the semiconductor substrate 1 lies is the contact region 100. The peak concentration of antimony in the contact region 100 is greater than the peak concentration of antimony in the non-contact region 101, and / or, the peak concentration of antimony in the first doped semiconductor layer 2 in the contact region 100 is greater than the peak concentration of antimony in the first doped semiconductor layer 2 in the non-contact region 101.

[0140] With the above technical solution, since the area where the orthogonal projection of the first electrode 4 onto the semiconductor substrate 1 is located is the contact region 100, when the peak concentration of antimony in the contact region 100 or the peak concentration of antimony in the first doped semiconductor layer 2 located in the contact region 100 is relatively large, the contact resistance can be further reduced, the carrier transport efficiency improved, and the bonding force between the first electrode 4 and the first doped semiconductor layer 2 enhanced. Furthermore, when printing the paste forming the first electrode 4 within the contact region 100, higher strength is required to reduce fragmentation. In this application, since the peak concentration of antimony in the first doped semiconductor layer 2 located within the contact region 100 is greater than the peak concentration of antimony in the first doped semiconductor layer 2 located within the non-contact region 101, the strength of the solar cell in the contact region 100 can be increased to reduce or eliminate the probability of fragmentation during the paste printing process.

[0141] In one alternative approach, see Figures 1 to 7 Within the first electrode region 10, the location of the maximum peak concentration of antimony is located in any one of the first doped semiconductor layer 2, the first passivation antireflection layer 3, the first electrode 4, and the contact transition layer.

[0142] In some embodiments, the peak concentration of antimony in the contact transition layer is greater than the peak concentration of antimony in any film layer of the solar cell.

[0143] As one possible implementation, the first passivation antireflection layer 3 includes an aluminum oxide layer 30 and an antireflection layer 31. The antireflection layer 31 includes a silicon nitride layer and a silicon oxynitride layer, with the silicon nitride layer formed on the aluminum oxide layer 30 and the silicon oxynitride layer formed on the silicon nitride layer.

[0144] In one alternative embodiment, for the sidewall 5, the non-contact area 101, and the bottom surface 111, or for the first non-electrode area 11 and the non-contact area 101, the peak concentration of antimony in the silicon oxynitride layer is greater than the peak concentration of antimony in the silicon nitride layer. This can improve the strength of the silicon oxynitride layer and reduce reliability risks.

[0145] In one alternative, for the sidewall 5, the non-contact area 101 and the bottom surface 111, or for the first non-electrode area 11 and the non-contact area 101, the peak concentration of antimony in the silicon oxynitride layer is greater than the peak concentration of antimony in the aluminum oxide layer 30.

[0146] With the above technical solution, since the silicon oxynitride layer covers the aluminum oxide layer 30 and is located on the outermost layer of the solar cell, it plays a protective role. Therefore, the silicon oxynitride layer needs to have greater film strength. As silicon wafers become thinner, the degree of deformation during production and transportation increases. However, in this application, because the silicon oxynitride layer has high strength, the probability of solar cell fragmentation can be reduced.

[0147] In one alternative approach, see Figures 1 to 7 For the sidewall 5, the non-contact area 101 and the bottom surface 111, or for the first non-electrode area 11 and the non-contact area 101, the peak concentration of antimony in the alumina layer 30 is greater than the peak concentration of antimony in the silicon nitride layer.

[0148] As one possible implementation, the aforementioned solar cell could be a back-contact solar cell. See also Figure 2 The first surface also includes a second electrode region 7. The first electrode region 10 and the second electrode region 7 are arranged alternately along a first direction B, and a first non-electrode region 11 is located between the first electrode region 10 and the second electrode region 7. The solar cell also includes a tunneling layer 8, a third doped semiconductor layer 9, and a second electrode 90. The tunneling layer 8 is disposed on the semiconductor substrate 1 and is located at least in the second electrode region 7. The third doped semiconductor layer 9, located in the second electrode region 7, is disposed on the side of the tunneling layer 8 away from the semiconductor substrate 1, and the doping type of the third doped semiconductor layer 9 is opposite to that of the first doped semiconductor layer 2. A first passivation antireflection layer 3 is also formed on the third doped semiconductor layer 9. The second electrode 90 is located in the second electrode region 7 and is connected to the third doped semiconductor layer 9 through the first passivation antireflection layer 3.

[0149] The aforementioned first non-electrode region 11 isolates the first doped semiconductor layer 2 and the third doped semiconductor layer 9, reducing the carrier recombination rate at the lateral boundary between the first doped semiconductor layer 2 and the third doped semiconductor layer 9, which is beneficial to improving the photoelectric conversion efficiency of the solar cell.

[0150] In one alternative approach, the surface of the second electrode region 7 has a third texture structure, which may be a tower-like texture structure.

[0151] For example, the tower-like textured structure is formed by polishing and is recessed downward relative to the surface of the semiconductor substrate 1, and its morphology presents an irregular shape such as rhombus, parallelogram, polygon or similar rhombus.

[0152] In one alternative approach, the second surface comprises a pyramidal or pyramid-like velvet structure.

[0153] Regarding the first doped semiconductor layer 2 and the third doped semiconductor layer 9, in terms of doping type, the first doped semiconductor layer 2 can be N-type, in which case the third doped semiconductor layer 9 is P-type; alternatively, the first doped semiconductor layer 2 can also be P-type, in which case the third doped semiconductor layer 9 is N-type. This embodiment of the invention does not specifically limit the doping type of the first doped semiconductor layer 2 and the third doped semiconductor layer 9, as long as their doping types are opposite. When the doping type is P-type, it is generally doped with a Group III element. When the doping type is N-type, it is generally doped with a Group V or Group VI element.

[0154] The materials of the first doped semiconductor layer 2 and / or the third doped semiconductor layer 9 may include any semiconductor material such as silicon, germanium-silicon, or germanium. In terms of the arrangement of matter, the crystal phase of the first doped semiconductor layer 2 and / or the third doped semiconductor layer 9 may be amorphous, microcrystalline, nanocrystalline, single-crystal, or polycrystalline. For example, the first doped semiconductor layer 2 and / or the third doped semiconductor layer 9 may be composed of one or more of polycrystalline silicon, amorphous silicon, and microcrystalline silicon. Preferably, the first doped semiconductor layer 2 includes a doped single-crystal silicon layer, i.e., a doped diffusion layer formed by diffusion on the surface of the semiconductor substrate 1, and the third doped semiconductor layer 9 includes a doped polycrystalline silicon layer.

[0155] As another possible implementation, the aforementioned solar cell could be a tunneling oxide passivated contact solar cell (i.e., a TOPCon cell). See also Figure 1 The second surface includes a third electrode region 91 and a second non-electrode region 92 alternately distributed along a first direction B. The solar cell also includes a tunneling layer 8, a fourth doped semiconductor layer 93, a second passivation antireflection layer 95, and a third electrode 94. The tunneling layer 8 is disposed on the semiconductor substrate 1, and is located at least in the third electrode region 91. The fourth doped semiconductor layer 93, located in the third electrode region 91, is disposed on the side of the tunneling layer 8 away from the semiconductor substrate 1. The doping type of the fourth doped semiconductor layer 93 is opposite to that of the first doped semiconductor layer 2. The second passivation antireflection layer 95 is located at least on the fourth doped semiconductor layer 93. The third electrode 94 is located in the third electrode region 91 and is connected to the fourth doped semiconductor layer 93 through the second passivation antireflection layer 95.

[0156] In one alternative approach, the second surface can be a tower-like textured structure, formed by polishing, recessed downwards relative to the surface of the semiconductor substrate 1, and exhibiting an irregular shape such as rhombus, parallelogram, polygon, or similar rhombus. The tower-like textured structure is more conducive to the deposition of the tunneling layer 8.

[0157] In one alternative approach, see Figure 1The heights of the third electrode region 91 and the second non-electrode region 92 can be equal, meaning the top surface of the third electrode region 91 and the top surface of the second non-electrode region 92 are on the same plane. Furthermore, the tunneling layer 8 is formed entirely on the second surface of the semiconductor substrate 1, the fourth doped semiconductor layer 93 is formed entirely on the surface of the tunneling layer 8 away from the semiconductor substrate 1, and the second passivation antireflection layer 95 is formed entirely on the fourth doped semiconductor layer 93.

[0158] In another alternative approach, along the thickness direction of the semiconductor substrate 1, the second non-electrode region 92 is higher than the third electrode region 91.

[0159] For example, along the thickness direction of the semiconductor substrate 1, the distance between the second non-electrode region 92 and the third electrode region 91 is greater than or equal to 2 μm and less than or equal to 6 μm.

[0160] The distance between the second non-electrode region 92 and the third electrode region 91 can be the distance between the top surface of the second non-electrode region 92 and the top surface of the third electrode region 91, or the distance between the bottom surface of the second non-electrode region 92 and the bottom surface of the third electrode region 91, or the distance between the bottom surface of the second non-electrode region 92 and the top surface of the third electrode region 91, or the distance between the top surface of the second non-electrode region 92 and the bottom surface of the third electrode region 91. For example, the distance between the second non-electrode region 92 and the third electrode region 91 can be 2μm, 2.5μm, 3μm, 3.5μm, 4μm, 4.5μm, 5μm, 5.5μm, or 6μm, etc.

[0161] If the distance between the second non-electrode region 92 and the third electrode region 91 along the thickness direction of the semiconductor substrate 1 is greater than 6 μm, and the third electrode region 91 is deeper, then a significant portion of the second surface of the semiconductor substrate 1 is removed, which reduces the overall mechanical strength of the solar cell. Furthermore, solar cells generate electricity by separating electrons and holes from light illuminating the semiconductor substrate 1. If too much of the semiconductor substrate 1 is removed, the light transmission path on the semiconductor substrate 1 will be reduced, and the light absorption rate on the semiconductor substrate 1 will decrease. This results in a reduction in the number of photogenerated carriers (holes and electrons) generated on the semiconductor substrate 1, thereby reducing the photoelectric conversion efficiency of the solar cell. In this application, the distance between the second non-electrode region 92 and the third electrode region 91 along the thickness direction of the semiconductor substrate 1 is set within the aforementioned range, ensuring a high light absorption rate of the semiconductor substrate 1, maintaining the photoelectric conversion efficiency of the solar cell, and ensuring sufficient mechanical strength of the solar cell.

[0162] For the doping type and crystal phase of the first doped semiconductor layer 2 and the fourth doped semiconductor layer 93, please refer to the description of the first doped semiconductor layer 2 and the third doped semiconductor layer 9 in the previous section on back contact solar cells, which will not be repeated here.

[0163] For back-contact solar cells and TOPCon cells, the chemical passivation of the tunneling layer 8 and the field passivation of the doped semiconductor layer can significantly reduce the recombination rate on the surface of the semiconductor substrate 1. The tunneling layer 8 and the doped semiconductor layer can further passivate the cell edges, reducing recombination at the cell edges. Furthermore, the tunneling layer 8 and the doped semiconductor layer form a passivated contact structure. While allowing majority carrier electrons to tunnel into the doped semiconductor layer, the tunneling layer 8 can block minority carrier hole recombination, thereby enabling electrons to be collected by the metal during lateral transport in the doped semiconductor layer, greatly reducing the metal contact recombination current, improving the open-circuit voltage and short-circuit current of the cell, and thus improving the cell efficiency.

[0164] See Figure 1 and Figure 2 Regarding the material and thickness of the tunneling layer 8, these can be set according to actual conditions and are not specifically limited here. For example, the material of the tunneling layer 8 may include one or more of silicon oxide, aluminum oxide, titanium oxide, hafnium dioxide, gallium oxide, tantalum pentoxide, niobium pentoxide, silicon nitride, silicon carbonitride, aluminum nitride, titanium nitride, and titanium carbonitride. The thickness of the tunneling layer 8 is greater than or equal to 1 nm and less than or equal to 2 nm; for example, the thickness of the tunneling layer 8 may be 1 nm, 1.2 nm, 1.5 nm, 1.7 nm, 1.8 nm, or 2 nm, etc.

[0165] Secondly, the present invention also provides a photovoltaic module. The photovoltaic module includes a cell string and an encapsulation layer. The cell string includes multiple interconnecting elements and multiple solar cells as described in the above-described technical solutions. The interconnecting elements connect the multiple solar cells in series, and the encapsulation layer covers the surface of the cell string.

[0166] The beneficial effects of the photovoltaic module provided by this invention are the same as those of the solar cell described in the above technical solution, and will not be repeated here.

[0167] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0168] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A solar cell, characterized in that, include: A semiconductor substrate, wherein the semiconductor substrate is doped with antimony; Along the thickness direction of the semiconductor substrate, the semiconductor substrate includes opposing first and second surfaces; The first surface includes a first electrode region and a first non-electrode region, and the first electrode region and the first non-electrode region have a height difference; A first doped semiconductor layer is located in the first electrode region, and a second doped semiconductor layer is located in the first non-electrode region. The doping concentration of the first doped semiconductor layer is greater than the doping concentration of the second doped semiconductor layer; or, the first doped semiconductor layer is located in the first electrode region, and no doped semiconductor layer is provided on the first non-electrode region. A first passivation anti-reflection layer is disposed on at least the first doped semiconductor layer and the second doped semiconductor layer; The first electrode is located in the first electrode region, and the first electrode passes through the first passivation antireflection layer and is electrically connected to the first doped semiconductor layer. The first doped semiconductor layer, the second doped semiconductor layer, and the first passivation antireflection layer all contain antimony. Within the first electrode region, the maximum peak concentration of antimony in the first doped semiconductor layer and the first passivation antireflection layer is n1; within the first non-electrode region, the maximum peak concentration of antimony in the second doped semiconductor layer and the first passivation antireflection layer is n2; wherein, n1 is greater than n2.

2. The solar cell according to claim 1, characterized in that, The first passivation antireflection layer includes at least an aluminum oxide layer; Within the first non-electrode region, the peak concentration of antimony in the second doped semiconductor layer and the peak concentration of antimony in the semiconductor substrate are both lower than the peak concentration of antimony in the alumina layer. Within the first electrode region, the peak concentration of antimony in the first doped semiconductor layer and the peak concentration of antimony in the semiconductor substrate are both lower than the peak concentration of antimony in the alumina layer.

3. The solar cell according to claim 1, characterized in that, The first passivation antireflection layer includes an aluminum oxide layer and an antireflection layer; the aluminum oxide layer is disposed on the first doped semiconductor layer and the second doped semiconductor layer, and the antireflection layer is disposed on the side of the aluminum oxide layer facing away from the semiconductor substrate; Within the first non-electrode region, the distance between the side of the antireflection layer facing away from the semiconductor substrate and the location of the peak concentration of antimony in the alumina layer is the first distance; Within the first electrode region, the distance between the side of the antireflection layer facing away from the semiconductor substrate and the location of the peak concentration of antimony in the alumina layer is the second distance; The directions of the first distance and the second distance are both consistent with the thickness direction of the semiconductor substrate; Wherein, the first distance is less than the second distance, and / or, the value range of the first distance is 60nm to 150nm, and / or, the value range of the second distance is 80nm to 180nm.

4. The solar cell according to claim 1, characterized in that, The peak concentration of antimony in the first doped semiconductor layer located in the first electrode region is greater than the peak concentration of antimony in the second doped semiconductor layer located in the first non-electrode region.

5. The solar cell according to claim 4, characterized in that, The peak concentration of antimony in the first doped semiconductor layer located in the first electrode region ranges from 2 × 10⁻⁶. 15 atom / cm 3 Up to 2×10 18 atom / cm 3 ; The peak concentration of antimony in the second doped semiconductor layer located within the first non-electrode region ranges from 1 × 10⁻⁶. 15 atom / cm 3 Up to 1×10 18 atom / cm 3 .

6. The solar cell according to claim 1, characterized in that, The first passivation antireflection layer includes at least an aluminum oxide layer; The thickness of the alumina layer located in the first electrode region is greater than the thickness of the alumina layer located in the first non-electrode region.

7. The solar cell according to claim 1 or 6, characterized in that, The first passivation antireflection layer includes at least an aluminum oxide layer; The peak concentration of antimony in the alumina layer located in the first electrode region is greater than the peak concentration of antimony in the alumina layer located in the first non-electrode region.

8. The solar cell according to claim 1 or 7, characterized in that, The peak concentration of antimony in the alumina layer located in the first electrode region ranges from 7 × 10⁻⁶. 16 atom / cm 3 Up to 5×10 18 atom / cm 3 ; The peak concentration of antimony in the alumina layer located in the first non-electrode region ranges from 5 × 10⁻⁶. 16 atom / cm 3 Up to 4×10 18 atom / cm 3 .

9. The solar cell according to claim 1, characterized in that, The first non-electrode region includes a sidewall and a bottom surface; the sidewall is located between the adjacent first electrode region and the bottom surface, and is inclined relative to the thickness direction of the semiconductor substrate; The first passivation antireflection layer includes at least an aluminum oxide layer; The thickness of the alumina layer located on the sidewall is greater than the thickness of the alumina layer located on the bottom surface; and / or, the thickness of the alumina layer located on the sidewall is greater than the thickness of the alumina layer located in the first electrode region.

10. The solar cell according to claim 1, characterized in that, The first passivation antireflection layer includes at least an aluminum oxide layer; the first surface includes a first intermediate region and a first edge region surrounding the first intermediate region; the thickness direction of the aluminum oxide layer located within the first intermediate region is consistent with the thickness direction of the semiconductor substrate; The thickness of the alumina layer located on at least a portion of the first edge region is greater than the thickness of the alumina layer located on the first middle region; And / or, the peak concentration of antimony in the alumina layer located in at least a portion of the first edge region is less than the peak concentration of antimony in the alumina layer located in the first middle region.

11. The solar cell according to claim 1, characterized in that, The semiconductor substrate includes a second intermediate region and a second edge region surrounding the second intermediate region; The concentration of antimony in the semiconductor substrate located in the second intermediate region is greater than the concentration of antimony in the semiconductor substrate located in at least a portion of the second edge region; The thickness direction of the semiconductor substrate located in the second intermediate region is consistent with the direction from the first surface to the second surface.

12. The solar cell according to claim 1, characterized in that, The semiconductor substrate includes a second intermediate region and a second edge region surrounding the second intermediate region; the thickness direction of the semiconductor substrate located within the second intermediate region is consistent with the direction from the first surface to the second surface; The peak concentration of antimony in the film layer located in at least a portion of the second edge region and within the first electrode region is less than the peak concentration of antimony in the film layer located in at least a portion of the second intermediate region and within the first electrode region; and / or, the peak concentration of antimony in the film layer located in at least a portion of the second edge region and within the first non-electrode region is less than the peak concentration of antimony in the film layer located in at least a portion of the second intermediate region and within the first non-electrode region.

13. The solar cell according to claim 1, characterized in that, The solar cell further includes a contact transition layer; the contact transition layer is located in the first electrode region and between the first electrode and the first doped semiconductor layer; the contact transition layer contains antimony.

14. The solar cell according to claim 13, characterized in that, The contact transition layer includes a metal oxide layer and / or a silicon oxide layer; The metal includes one or more of silver, copper, aluminum, nickel, lead, or bismuth.

15. The solar cell according to claim 1, characterized in that, The first electrode region includes a contact region and a non-contact region; Along the thickness direction of the semiconductor substrate, the region where the orthogonal projection of the first electrode on the semiconductor substrate is located is the contact area; The peak concentration of antimony in the contact region is greater than the peak concentration of antimony in the non-contact region; and / or, the peak concentration of antimony in the first doped semiconductor layer in the contact region is greater than the peak concentration of antimony in the first doped semiconductor layer in the non-contact region.

16. The solar cell according to claim 1, characterized in that, The first surface also includes a second electrode region, the first electrode region and the second electrode region are arranged alternately, and the first non-electrode region is located between the first electrode region and the second electrode region; The solar cell also includes: A tunneling layer is disposed on the semiconductor substrate, and the tunneling layer is located at least in the second electrode region; The third doped semiconductor layer, located in the second electrode region, is disposed on the side of the tunneling layer away from the semiconductor substrate, and the doping type of the third doped semiconductor layer is opposite to that of the first doped semiconductor layer. The first passivation antireflection layer is also formed on the third doped semiconductor layer; The second electrode is located in the second electrode region; the second electrode passes through the first passivation antireflection layer and is connected to the third doped semiconductor layer.

17. The solar cell according to claim 1, characterized in that, The second surface includes a third electrode region and a second non-electrode region that are alternately distributed along the first direction; The solar cell also includes: A tunneling layer is disposed on the semiconductor substrate, and the tunneling layer is located at least in the third electrode region; A fourth doped semiconductor layer is disposed on the side of the tunneling layer away from the semiconductor substrate, located in the third electrode region; the doping type of the fourth doped semiconductor layer is opposite to that of the first doped semiconductor layer. A second passivation and anti-reflection layer is disposed at least on the fourth doped semiconductor layer; The third electrode is located in the third electrode region; the third electrode passes through the second passivation antireflection layer and is connected to the fourth doped semiconductor layer.

18. A photovoltaic module, characterized in that, Including battery strings and encapsulation layers; The battery string includes a plurality of interconnecting elements and a plurality of solar cells as described in any one of claims 1 to 17; the interconnecting elements connect the plurality of solar cells in series; The encapsulation layer is used to cover the surface of the battery string.

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