Solar cell and photovoltaic module

Abstract

The invention discloses a solar cell and a photovoltaic module, relates to the technical field of photovoltaics, and is used for enabling a passivation layer to have a good passivation effect on a semiconductor substrate and increasing the surface roughness of one side, away from the semiconductor substrate, of the passivation layer through a plurality of cone-like bulge structures which are distributed discretely. The specific surface area of the doped semiconductor layer in the passivation layer or formed on the passivation layer is increased, the contact performance of the doped semiconductor layer and the electrode and the shaping of the electrode are improved, and the conversion efficiency of the solar cell is improved. The solar cell includes a semiconductor substrate and a passivation layer. The semiconductor substrate has a first surface and a second surface opposite to each other. At least one of the first surface and the second surface is a target surface. The passivation layer is disposed on the target surface. The surface of the side, away from the semiconductor substrate, of the passivation layer is provided with a plurality of non-pyramid texture structures and a plurality of cone-like protrusion structures which are distributed discretely. The solar cell is applied to the photovoltaic module.

Description

Technical Field

[0001] The invention relates to the field of photovoltaic technology, and in particular to a solar cell and a photovoltaic module. Background Art

[0002] As a green energy source, solar cells play a positive role in energy conservation and emission reduction. With the development of the photovoltaic industry, solar cell technology has become increasingly mature. Among them, photovoltaic solar cells are devices that convert sunlight into electrical energy. Specifically, solar cells use the photovoltaic principle to generate carriers, and then use electrodes to lead out the carriers, thereby facilitating the effective use of electrical energy. As an environmentally friendly and renewable energy source, solar energy has received more and more attention in recent years. Correspondingly, the application scope of photovoltaic solar cells based on the photoelectric effect is also becoming wider and wider.

[0003] However, it is difficult for existing solar cells to achieve both good passivation effects and good electrode contact performance and shaping, which is not conducive to improving the conversion efficiency of solar cells. Summary of the invention

[0004] The object of the present invention is to provide a solar cell and a photovoltaic module, which are used to make the passivation layer have a good passivation effect on the semiconductor substrate, while increasing the surface roughness of the passivation layer away from the semiconductor substrate through a plurality of discretely distributed cone-shaped protrusion structures, which is beneficial to increase the specific surface area of ​​the doped semiconductor layer in the passivation layer or formed between the passivation layer and the semiconductor substrate, improve the contact performance between the doped semiconductor layer and the electrode, and the shaping of the electrode, thereby improving the conversion efficiency of the solar cell.

[0005] In order to achieve the above-mentioned object, in a first aspect, the present invention provides a solar cell, which comprises: a semiconductor substrate and a passivation layer. The semiconductor substrate has a first surface and a second surface opposite to each other. At least one of the first surface and the second surface is a target surface. The passivation layer is arranged on the target surface. The surface of the passivation layer on one side away from the semiconductor substrate has a plurality of non-pyramid texture structures, and has a plurality of discretely distributed conical convex structures.

[0006] In the case of adopting the above technical solution, the passivation layer is arranged on the target surface of the semiconductor substrate, and one side of the target surface of the semiconductor substrate can be passivated to reduce the carrier recombination rate. In addition, the side of the passivation layer away from the semiconductor substrate has a plurality of non-pyramid-type texture structures, and the non-pyramid-type texture structure does not have a sharp vertex angle like the pyramid texture structure, which is conducive to reducing the degree of undulation of the passivation layer away from the semiconductor substrate, so that the surface of the side of the passivation layer away from the semiconductor substrate is relatively flat from a macroscopic perspective. In addition, in the actual manufacturing process, the passivation layer is formed on the target surface of the semiconductor substrate through deposition and other processes and in a similar layer-by-layer covering manner. Therefore, when the surface of the side of the passivation layer away from the semiconductor substrate is relatively flat in the macroscopic sense, the target surface of the semiconductor substrate is also likely to be a relatively flat surface, which is conducive to improving the formation quality and film thickness of the passivation layer on the target surface, and then it is conducive to improving the passivation effect of the passivation layer on the semiconductor substrate and improving the conversion efficiency of the solar cell.

[0007] In addition, in addition to a plurality of non-pyramid-type texture structures, the surface of the passivation layer on the side away from the semiconductor substrate also has a plurality of discretely distributed quasi-conical protrusion structures. Specifically, the quasi-conical protrusion structure refers to a conical protrusion structure with a smooth top angle. At this time, the surface morphology of the quasi-conical protrusion structure is relatively smooth, and different quasi-conical protrusion structures are distributed in a discrete manner rather than in an adjacent and dense manner, so that their distribution density on the side of the passivation layer away from the semiconductor substrate is relatively small, which can ensure that the surface of the passivation layer on the side away from the semiconductor substrate is relatively flat from a macroscopic perspective; secondly, because the quasi-conical protrusion structure has a certain degree of undulation relative to the surface of the passivation layer, it is different from the surface of the passivation layer that is only provided with a non-pyramid-type texture structure (such as a tower-like texture structure or a linear texture structure). When the surface of the passivation layer facing away from the semiconductor substrate also has the above-mentioned cone-like protrusion structure, the side of the passivation layer facing away from the semiconductor substrate can have a relatively large surface roughness at the microscopic level, which is beneficial to increase the doped semiconductor layer included in the passivation layer, or the doped semiconductor layer formed between the passivation layer and the semiconductor substrate has a larger specific surface area, thereby increasing the contact area between the doped semiconductor layer and the electrode, improving the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is beneficial to improving the conversion efficiency of the solar cell.

[0008] As a possible implementation solution, a distance between two adjacent cone-like protrusion structures is greater than or equal to 0.5 μm and less than or equal to 3 μm.

[0009] In the case of adopting the above technical solution, when other factors are the same, the smaller the spacing between two adjacent cone-like protrusion structures, the greater the distribution density of the cone-like protrusion structures on the side of the passivation layer away from the semiconductor substrate, so that the surface roughness of the passivation layer on the side away from the semiconductor substrate is greater. On the contrary, the larger the spacing between two adjacent cone-like protrusion structures, the smaller the distribution density of the cone-like protrusion structures on the side of the passivation layer away from the semiconductor substrate, so that the surface roughness of the passivation layer on the side away from the semiconductor substrate is smaller. Based on this, when the spacing between two adjacent cone-like protrusion structures is within the above range, it can be prevented that the surface roughness of the passivation layer on the side away from the semiconductor substrate is larger due to the small spacing, ensuring that the target surface of the semiconductor substrate has a relatively flat surface, further improving the formation quality of the passivation layer on the target surface, and facilitating the increase of the film thickness of the passivation layer, which is conducive to further improving the passivation effect of the passivation layer on the semiconductor substrate. In addition, it can also prevent the surface roughness of the passivation layer on the side facing away from the semiconductor substrate from being smaller due to the large spacing, which is beneficial to further increase the specific surface area of ​​the above-mentioned doped semiconductor layer, and then increase the contact area between the doped semiconductor layer and the electrode, further improve the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is beneficial to improve the conversion efficiency of the solar cell.

[0010] As a possible implementation scheme, the solar cell further includes a collector electrode disposed on the side of the passivation layer away from the semiconductor substrate. The width of the collector electrode is greater than ten times the distance between two adjacent cone-like protrusion structures. In this case, the distance between two adjacent cone-like protrusion structures can be prevented from being too large. The beneficial effects thereof can be referred to in the foregoing text and will not be described in detail here.

[0011] As a possible implementation solution, the height of the quasi-conical protrusion structure is greater than or equal to 0.2 μm and less than or equal to the height of the non-pyramid texture structure.

[0012] In the case of adopting the above technical solution, when other factors are the same, the height of the quasi-conical protrusion structure is proportional to its own undulation degree and proportional to the surface roughness of the side of the passivation layer away from the semiconductor substrate. Based on this, when the height of the quasi-conical protrusion structure is within the above range, it is beneficial to prevent the surface roughness of the passivation layer away from the semiconductor substrate from being too small due to the height being too small, and it is beneficial to further increase the specific surface area of ​​the above-mentioned doped semiconductor layer, thereby increasing the contact area between the doped semiconductor layer and the electrode, and further improving the contact performance between the doped semiconductor layer and the electrode, as well as the adhesion and shaping of the electrode on the doped semiconductor layer. In addition, it can also prevent the surface roughness of the passivation layer away from the semiconductor substrate from being too large due to the height being too large, ensuring that the target surface of the semiconductor substrate on which the passivation layer is formed has a relatively flat surface, further improving the formation quality of the passivation layer on the target surface, and increasing the film thickness of the passivation layer, which is beneficial to further improve the passivation effect of the passivation layer on the semiconductor substrate, and is beneficial to improving the conversion efficiency of the solar cell.

[0013] As a possible implementation scheme, the height of the above-mentioned cone-like protrusion structure is less than or equal to 0.5 μm. In this case, the height of the cone-like protrusion structure can be prevented from being too large. Its beneficial effects can be referred to above and will not be repeated here.

[0014] As a possible implementation scheme, the height of the above-mentioned cone-like protruding structure is smaller than the bottom diameter of the cone-like protruding structure.

[0015] When the above technical solution is adopted, compared with the "tall and thin" cone-like protrusion structure whose height is smaller than its bottom diameter, when the height of the cone-like protrusion structure is smaller than the bottom diameter of the cone-like protrusion structure, the cone-like protrusion structure is "short and fat", ensuring that the side of the passivation layer away from the semiconductor substrate has a relatively small degree of undulation, ensuring that the side of the passivation layer away from the semiconductor substrate and the target surface of the semiconductor substrate are macroscopically flat surfaces, further improving the formation quality of the passivation layer on the target surface, and is conducive to increasing the film thickness of the passivation layer, and then helping to improve the passivation effect of the passivation layer on the semiconductor substrate, thereby improving the conversion efficiency of solar cells.

[0016] As a possible implementation solution, the diameter of the cone-like protrusion structure is greater than or equal to 0.5 μm and less than or equal to 0.65 μm.

[0017] In the case of adopting the above technical solution, it can be understood that, under the same other factors, the smaller the diameter of the quasi-conical convex structure, the smaller the angle corresponding to its rounded vertex angle, so that it is similar to a "thin and tall" type. On the contrary, the larger the diameter of the quasi-conical convex structure, the larger the angle corresponding to its rounded vertex angle, so that it is similar to a "short and fat" type. Based on this, when the diameter of the quasi-conical convex structure is within the above range, it is beneficial to prevent the surface roughness of the passivation layer from the side of the semiconductor substrate due to the smaller diameter, ensure that the target surface of the semiconductor substrate has a relatively flat surface, further improve the formation quality of the passivation layer on the target surface, and increase the film thickness of the passivation layer, which is beneficial to further improve the passivation effect of the passivation layer on the semiconductor substrate. In addition, it can also prevent the surface roughness of the passivation layer from the side of the semiconductor substrate due to the larger diameter, which is beneficial to further increase the specific surface area of ​​the above-mentioned doped semiconductor layer, thereby increasing the contact area between the doped semiconductor layer and the electrode, further improve the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is beneficial to improve the conversion efficiency of the solar cell.

[0018] As a possible implementation scheme, the non-pyramid texture structure includes a linear protrusion structure, and the surface of the linear protrusion structure has a cone-like protrusion structure.

[0019] When the above technical solution is adopted, compared with the pyramid-shaped texture structure, the linear protrusion structure has a smaller degree of undulation, ensuring that the side of the passivation layer away from the semiconductor substrate is macroscopically flat, thereby improving the passivation effect of the passivation layer. Secondly, the surface of the linear protrusion structure has a cone-like protrusion structure. The existence of this type of cone-like protrusion structure makes the surface of the linear protrusion structure that originally has an undulating morphology superimposed with the degree of undulation of the cone-like protrusion structure, which is conducive to further increasing the microscopic surface roughness of the side of the passivation layer away from the semiconductor substrate, and is conducive to further increasing the specific surface area of ​​the above-mentioned doped semiconductor layer, thereby increasing the contact area between the doped semiconductor layer and the electrode, further improving the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is conducive to improving the conversion efficiency of solar cells.

[0020] As a possible implementation scheme, the non-pyramid texture structure includes a base-like texture structure, and the surface of the base-like texture structure has a cone-like protrusion structure. The application principle of the beneficial effect in this case can refer to the application principle of the beneficial effect of the non-pyramid texture structure including a linear protrusion structure, and the surface of the linear protrusion structure has a cone-like protrusion structure, which will not be repeated here.

[0021] As a possible implementation scheme, only one of the first and second surfaces is the target surface. Along the direction parallel to the target surface, the passivation layer includes a first doped semiconductor portion and a second doped semiconductor portion that are alternately distributed. The conductivity types of the first doped semiconductor portion and the second doped semiconductor portion are opposite, and at least a portion of the first doped semiconductor portion and at least a portion of the second doped semiconductor portion are spaced apart. Among them, the side surface of the passivation layer corresponding to the first doped semiconductor portion that is away from the semiconductor substrate is the first sub-surface, and the side surface of the passivation layer corresponding to the second doped semiconductor portion that is away from the semiconductor substrate is the second sub-surface. The spacing between two adjacent quasi-conical convex structures on the first sub-surface is different from the spacing between two adjacent quasi-conical convex structures on the second sub-surface; or, only one of the first sub-surface and the second sub-surface has a quasi-conical convex structure.

[0022] When the above technical solution is adopted, as described above, when the spacings between adjacent cone-like protrusion structures are different, the surface roughness of the passivation layer on the side away from the semiconductor substrate is different. Secondly, when other factors are the same, compared with the first sub-surface without the cone-like protrusion structure, the second sub-surface having the cone-like protrusion structure has a relatively larger surface roughness at the microscopic level. In the above case, when the spacing between two adjacent cone-like protrusion structures on the first sub-surface is different from the spacing between two adjacent cone-like protrusion structures on the second sub-surface; or only one of the first sub-surface and the second sub-surface has a cone-like protrusion structure, whether the first sub-surface and the second sub-surface have cone-like protrusion structures and the spacing between the cone-like protrusion structures can be set respectively according to the requirements for different passivation effects of the first doped semiconductor part and the second doped semiconductor part in the actual application scenario, and the requirements for the contact performance between the two and the corresponding electrodes, so that the two parts of the passivation layer corresponding to the first doped semiconductor part and the second doped semiconductor part respectively have different passivation effects on the semiconductor substrate, and are conducive to making the first doped semiconductor part and the second doped semiconductor part have different surface morphologies, thereby facilitating reducing the passivation difference between the two parts of the passivation layer corresponding to the first doped semiconductor part and the second doped semiconductor part respectively, and facilitating reducing the difference in contact performance between the first doped semiconductor part and the second doped semiconductor part and the corresponding electrodes respectively.

[0023] As a possible implementation scheme, when both the first sub-surface and the second sub-surface have cone-like protrusion structures and the conductivity type of the first doped semiconductor part is P-type, the spacing between two adjacent cone-like protrusion structures on the first sub-surface is greater than the spacing between two adjacent cone-like protrusion structures on the second sub-surface; or, the top angle of the cone-like protrusion structure on the first sub-surface is smaller than the top angle of the cone-like protrusion structure on the second sub-surface.

[0024] In the case of adopting the above technical solution, due to the limitation of doping solid concentration and doping difficulty, the dopant concentration of the dopant in the N-type doped semiconductor part is greater than the doping concentration of the dopant in the P-type doped semiconductor part, and the passivation characteristics of the P-type doped semiconductor part are relatively poor. Based on this, when the conductivity type of the first doped semiconductor part is P-type, and the first sub-surface corresponding to the first doped semiconductor part on the side of the passivation layer away from the semiconductor substrate has a spacing between two adjacent cone-like protrusion structures, which is greater than the spacing between two adjacent cone-like protrusion structures on the second sub-surface (the surface of the region corresponding to the N-type doped semiconductor part on the side of the passivation layer away from the semiconductor substrate), the first sub-surface has a relatively small surface roughness, so that the first sub-surface is relatively flat in macroscopic terms, and accordingly, the portion corresponding to the first sub-surface in the target surface of the semiconductor substrate is also likely to be a relatively flat surface, which is conducive to improving the formation quality and film thickness of the P-type doped semiconductor part on the target surface, and further conducive to improving the passivation effect of the P-type doped semiconductor part on the semiconductor substrate. While under the condition that other factors are the same, when the apex angle of the cone-like protrusion structure on the first sub-surface is smaller than the apex angle of the cone-like protrusion structure on the second sub-surface, the expansion degree of the two relative side edges constituting the apex angle is smaller. At this time, the bottom surface of the cone-like protrusion structure on the first sub-surface is conducive to making the distribution density of the cone-like protrusion structure on the first sub-surface sparse, thereby reducing the surface roughness of the first sub-surface, which is conducive to improving the passivation effect of the P-type doped semiconductor part on the semiconductor substrate, reducing the difference in the passivation effects of the P-type doped semiconductor part and the N-type doped semiconductor part on the semiconductor substrate respectively, and further improving the conversion efficiency of the solar cell.

[0025] As a possible implementation scheme, when both the first sub-surface and the second sub-surface have a cone-like convex structure, and the conductivity type of the first doped semiconductor portion is P-type, the bottom diameter of the cone-like convex structure on the first sub-surface is smaller than the bottom diameter of the cone-like convex structure on the second sub-surface; or, the height of the cone-like convex structure on the first sub-surface is greater than the height of the cone-like convex structure on the second sub-surface. The application principle of the beneficial effect in this case can refer to the application principle of the beneficial effect of the spacing between two adjacent cone-like convex structures on the first sub-surface being greater than the spacing between two adjacent cone-like convex structures on the second sub-surface as described above, which will not be repeated here.

[0026] As a possible implementation scheme, the surface of the passivation layer on the side away from the semiconductor substrate has a first area and a second area that do not overlap each other. The solar cell also includes a collector electrode arranged on the side of the passivation layer away from the semiconductor substrate, and the collector electrode is located on at least a portion of the first area. The non-pyramid texture structure and the cone-like protrusion structure are both distributed in the first area. The surface of the second area has a densely distributed pyramid texture structure. Among them, the height of the pyramid texture structure is greater than the height of the cone-like protrusion structure, and / or the bottom side length of the pyramid texture structure is greater than the bottom diameter of the cone-like protrusion structure.

[0027] When the above technical solution is adopted, as described above, compared with the surface formed with the pyramidal texture structure, the surface having the above non-pyramid texture structure and the quasi-conical convex structure is macroscopically flat; but compared with the surface having only the non-pyramid texture structure such as the base-shaped texture structure, the surface having the above non-pyramid texture structure and the quasi-conical convex structure has a relatively large surface roughness at the microscopic level. In addition, the collector electrode included in the solar cell needs to be in electrical contact with the above doped semiconductor layer to collect and conduct carriers. Based on this, on the side of the passivation layer away from the semiconductor substrate, a non-pyramid texture structure with a small degree of undulation and a cone-like protrusion structure are distributed on the surface of at least the first region corresponding to the collector electrode, so that the surface of the first region and the surface of the region corresponding to the first region in the target surface are relatively flat, which is conducive to improving the formation quality of the doped semiconductor layer on the surface of the target surface corresponding to the first region, and increasing the film thickness of the doped semiconductor layer, and improving the passivation effect of the doped semiconductor layer; and the presence of the cone-like protrusion structure on the first region is also conducive to increasing the contact area between the doped semiconductor layer and the collector electrode, improving the contact performance between the doped semiconductor layer and the collector electrode, and the attachment and shaping of the collector electrode on the doped semiconductor layer. In addition, the surface of the second region of the passivation layer has a densely distributed pyramid texture structure, which can improve the surface light trapping effect of the second region, which is conducive to improving the conversion efficiency of solar cells.

[0028] In a second aspect, the present invention provides a photovoltaic module, which includes the solar cell provided by the first aspect and various implementations thereof.

[0029] The beneficial effects of the second aspect of the present invention and its various implementations can be analyzed by referring to the beneficial effects of the first aspect and its various implementations, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0031] Figure 1 is a SEM image of a local surface of a passivation layer facing away from a semiconductor substrate in the related art;

[0032] Figure 2 A schematic longitudinal cross-sectional view of a first structure of a solar cell provided by an embodiment of the present invention;

[0033] Figure 3 A schematic longitudinal cross-sectional view of a second structure of a solar cell provided by an embodiment of the present invention;

[0034] Figure 4 A schematic longitudinal cross-sectional view of a third structure of a solar cell provided by an embodiment of the present invention;

[0035] Figure 5 This is a SEM image of a local surface of the passivation layer facing away from the semiconductor substrate in an embodiment of the present invention. Figure 1 ;

[0036] Figure 6 This is a SEM image of a local surface of the passivation layer facing away from the semiconductor substrate in an embodiment of the present invention. Figure 2 ;

[0037] Figure 7 The SEM image of the local surface of the target surface in the embodiment of the present invention is Figure 1 ;

[0038] Figure 8 A schematic longitudinal cross-sectional view of a fourth structure of a solar cell provided by an embodiment of the present invention;

[0039] Fig. 9 A schematic longitudinal cross-sectional view of a fifth structure of a solar cell provided by an embodiment of the present invention;

[0040] Fig.10 A schematic longitudinal cross-sectional view of a sixth structure of a solar cell provided by an embodiment of the present invention.

[0041] Figure numerals: 11 is a semiconductor substrate, 12 is a first surface, 13 is a second surface, 14 is a passivation layer, 15 is a non-pyramid texture structure, 16 is a cone-shaped protrusion structure, 17 is a first doped semiconductor part, 18 is a second doped semiconductor part, 19 is a doped semiconductor layer, 20 is an interface passivation layer, 21 is a surface passivation layer, 22 is an anti-reflection layer, and 23 is a transparent conductive layer. DETAILED DESCRIPTION

[0042] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concept of the present invention.

[0043] Various structural schematic diagrams according to embodiments of the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for a clearer expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0044] In the context of the present invention, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. In addition, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "under" the other layer / element. In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0045] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0046] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] As a green energy source, solar cells play a positive role in energy conservation and emission reduction. With the development of the photovoltaic industry, solar cell technology has become increasingly mature. Among them, photovoltaic solar cells are devices that convert sunlight into electrical energy. Specifically, solar cells use the photovoltaic principle to generate carriers, and then use electrodes to lead out the carriers, thereby facilitating the effective use of electrical energy. As an environmentally friendly and renewable energy source, solar energy has received more and more attention in recent years. Correspondingly, the application scope of photovoltaic solar cells based on the photoelectric effect is also becoming wider and wider.

[0048] Specifically, existing solar cells generally include a semiconductor substrate and a passivation layer formed on the semiconductor substrate. The passivation layer may include a doped semiconductor layer with a field passivation effect, or may include an interface passivation layer and / or a surface passivation layer with a chemical passivation effect. Figure 1 As shown, the surface of one side of the semiconductor substrate on which the passivation layer is formed can be a simple polished surface. In this case, the surface has a relatively flat morphology, which is conducive to improving the formation quality of the passivation layer and improving the passivation effect of the passivation layer on the semiconductor substrate. However, the passivation layer formed on the semiconductor substrate with a flat surface also tends to be flat, which makes the electrode material poorly shaped and adhered on the flat surface when forming an electrode for extracting carriers on the passivation layer, thereby reducing the selection and matching of the electrode material; at the same time, it also causes the contact area between the formed electrode and the doped semiconductor layer formed on the plane surface to become smaller, and the contact loss increases. Although the pyramid-shaped velvet surface with an undulating morphology has a large surface roughness, which is conducive to improving the electrical contact performance between the electrode and the doped semiconductor layer, as well as the shaping and adhesion of the electrode, the surface morphology of the pyramid-shaped velvet surface is too undulating and the surface is too sharp, resulting in poor formation quality of the doped semiconductor layer on the velvet surface, and its passivation effect is deteriorated. It can be seen that it is difficult for existing solar cells to take into account both good passivation effect and good electrode contact performance and shaping, which is not conducive to improving the conversion efficiency of solar cells.

[0049] In order to solve the above technical problems, in a first aspect, an embodiment of the present invention provides a solar cell. Figures 2 to 7 As shown, the solar cell provided by the embodiment of the present invention includes: a semiconductor substrate 11 and a passivation layer 14. The semiconductor substrate 11 has a first surface 12 and a second surface 13 opposite to each other. At least one of the first surface 12 and the second surface 13 is a target surface. The passivation layer 14 is arranged on the target surface. The surface of the passivation layer 14 on one side away from the semiconductor substrate 11 has a plurality of non-pyramid texture structures 15, and has a plurality of discretely distributed conical convex structures 16.

[0050] When the above technical solution is adopted, Figures 2 to 7As shown, the passivation layer 14 is arranged on the target surface of the semiconductor substrate 11, and can passivate one side of the target surface of the semiconductor substrate 11 to reduce the carrier recombination rate. In addition, the side of the passivation layer 14 away from the semiconductor substrate 11 has a plurality of non-pyramid texture structures 15, and the non-pyramid texture structures 15 do not have a sharp vertex angle like the pyramid texture structure, which is conducive to reducing the undulation degree of the side of the passivation layer 14 away from the semiconductor substrate 11, so that the surface of the side of the passivation layer 14 away from the semiconductor substrate 11 is relatively flat from a macroscopic perspective. In addition, in the actual manufacturing process, the passivation layer 14 is formed on the target surface of the semiconductor substrate 11 through deposition and other processes and in a similar layer-by-layer covering manner. Therefore, when the surface of the side of the passivation layer 14 away from the semiconductor substrate 11 is relatively flat in macroscopic terms, the target surface of the semiconductor substrate 11 is also likely to be a relatively flat surface, which is conducive to improving the formation quality and film thickness of the passivation layer 14 on the target surface, and then it is conducive to improving the passivation effect of the passivation layer 14 on the semiconductor substrate 11, and improving the conversion efficiency of the solar cell. In addition, the surface of the passivation layer 14 on the side away from the semiconductor substrate 11 has a plurality of discretely distributed conical-like protrusion structures 16 in addition to a plurality of non-pyramid-type texture structures 15. Specifically, the conical-like protrusion structure 16 refers to a conical protrusion structure with a smooth top. At this time, the surface morphology of the conical-like protrusion structure 16 is relatively smooth, and different conical-like protrusion structures 16 are distributed in a discrete manner rather than being closely adjacent to each other, so that the distribution density of the conical-like protrusion structures 16 on the side away from the semiconductor substrate 11 of the passivation layer 14 is relatively small, which can ensure that the surface of the passivation layer 14 on the side away from the semiconductor substrate 11 is relatively flat from a macroscopic point of view; secondly, because the conical-like protrusion structures 16 have a certain degree of undulation relative to the surface of the passivation layer 14, they are different from those only provided with non-pyramid-type texture structures 15 (such as tower-like texture structures or linear texture structures). When the surface of the passivation layer 14 facing away from the semiconductor substrate 11 also has the above-mentioned conical-like protrusion structure 16, the side of the passivation layer 14 facing away from the semiconductor substrate 11 can have a relatively large surface roughness at the microscopic level, which is beneficial to increase the doped semiconductor layer included in the passivation layer 14, or the doped semiconductor layer formed between the passivation layer 14 and the semiconductor substrate 11 has a larger specific surface area, thereby increasing the contact area between the doped semiconductor layer and the electrode, improving the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is beneficial to improving the conversion efficiency of the solar cell.

[0051] In actual application, the solar cell provided by the embodiment of the present invention can be a double-sided contact cell, that is, one of the positive electrode and the negative electrode of the solar cell is arranged on the front side of the cell, and the other is arranged on the back side of the cell. Alternatively, the solar cell provided by the embodiment of the present invention can also be a back contact cell, that is, the positive electrode and the negative electrode of the solar cell are both arranged on the back side of the cell.

[0052] Secondly, the solar cell provided in the embodiment of the present invention may be a cell having a tunneling passivation contact structure or a heterogeneous contact structure, or may be a conventional solar cell without the interface passivation layer included in the above selective contact structure.

[0053] Specifically, the embodiment of the present invention does not specifically limit the material of the semiconductor substrate. For example, the semiconductor substrate can be a substrate made of any semiconductor material such as a silicon substrate, a silicon germanium substrate, a germanium substrate or a gallium arsenide substrate.

[0054] As for the first surface and the second surface of the semiconductor substrate, the first surface of the semiconductor substrate may correspond to the front surface of the solar cell, and the second surface of the semiconductor substrate may correspond to the back surface of the solar cell; or, the first surface of the semiconductor substrate may correspond to the back surface of the solar cell, and the second surface of the semiconductor substrate may correspond to the front surface of the solar cell. Secondly, whether the first surface and the second surface are target surfaces can be determined according to the type of solar cell and the corresponding relationship between the first surface and the second surface and the front surface and the back surface of the cell, respectively, and no specific limitation is made here.

[0055] For example, when the solar cell is a double-sided contact cell, of the first and second surfaces of the semiconductor substrate, only the first surface may be the target surface, only the second surface may be the target surface, or both the first and second surfaces may be the target surface.

[0056] Exemplarily, in the case where the solar cell is a back-contact cell, one of the first surface and the second surface of the semiconductor substrate corresponding to the back side of the cell is the target surface.

[0057] As for the surface morphology of the target surface of the semiconductor substrate, as described above, when the surface of the passivation layer facing away from the semiconductor substrate is macroscopically flat, the target surface formed with the passivation layer is also likely to be a relatively flat surface. Based on this, the specific surface morphology of the target surface of the semiconductor substrate can be determined according to the actual application scenario, as long as it can be applied to the solar cell provided in the embodiment of the present invention.

[0058] For the above-mentioned passivation layer, the passivation layer is arranged on the target surface, and the surface of the passivation layer facing away from the semiconductor substrate is the front and / or back of the solar cell. In terms of structure and material, the specific structure of the passivation layer can be determined according to the type of solar cell and the actual application scenario, and is not specifically limited here. Exemplarily, the passivation layer may include at least one of a doped semiconductor layer, an interface passivation layer, a surface passivation layer, an anti-reflection layer, and a transparent conductive layer.

[0059] Among them, Figures 1 to 4As shown, in the case where the passivation layer 14 is only a doped semiconductor layer, the non-pyramid texture structure and the cone-like protrusion structure are both formed on the side of the doped semiconductor layer away from the semiconductor substrate 11. The material of the passivation layer 14 may include any semiconductor material such as silicon, silicon germanium or germanium. The crystal phase of the passivation layer 14 may be single crystal, polycrystalline, microcrystalline, nanocrystalline or amorphous.

[0060] like Figures 5 to 8 As shown, when the passivation layer 14 only includes at least one of the surface passivation layer 21, the anti-reflection layer 22 and the transparent conductive layer, the non-pyramid texture structure 15 and the quasi-cone-shaped protrusion structure 16 are both formed on the outermost one of the film layers included in the passivation layer 14 (i.e., the one with the largest distance from the semiconductor substrate 11 along the thickness direction of the battery), and the surface of the side away from the semiconductor substrate 11. For example: when the passivation layer 14 only includes the surface passivation layer 21 and the anti-reflection layer 22, and the anti-reflection layer 22 is arranged on the side of the surface passivation layer 21 away from the semiconductor substrate 11, the non-pyramid texture structure 15 and the quasi-cone-shaped protrusion structure 16 are both formed on the side of the anti-reflection layer 22 away from the semiconductor substrate 11. In addition, the materials of the surface passivation layer 21, the anti-reflection layer 22 and the transparent conductive layer can be set according to actual needs. Exemplarily, the material of the surface passivation layer 21 can include any material with a passivation effect such as silicon oxide, aluminum oxide, silicon nitride or silicon oxynitride. The material of the anti-reflection layer 22 may include silicon nitride or silicon oxynitride, etc. The material of the above-mentioned transparent conductive layer may include at least one of fluorine-doped tin oxide, aluminum-doped zinc oxide, tin-doped indium oxide, tungsten-doped indium oxide, molybdenum-doped indium oxide, cerium-doped indium oxide and indium hydroxide. In the above case, the solar cell provided by the embodiment of the present invention also includes a doped semiconductor layer 19 arranged in or on the target surface (when the doped semiconductor layer 19 is arranged on the target surface, the material of the doped semiconductor layer 19 can refer to the above text and will not be repeated here), and the passivation layer is located on the side of the doped semiconductor layer 19 away from the semiconductor substrate 11.

[0061] like Figures 5 to 7 ,as well as Fig. 9As shown, in the case where the passivation layer 14 includes at least one of a surface passivation layer, an anti-reflection layer and a transparent conductive layer 23 in addition to the doped semiconductor layer 19, the non-pyramid texture structure 15 and the quasi-cone-shaped protrusion structure 16 are both formed on the outermost one of the film layers included in the passivation layer 14 (i.e., the one with the largest distance from the semiconductor substrate 11 along the thickness direction of the battery), and the surface of the side away from the semiconductor substrate 11. For example: when the passivation layer 14 only includes the doped semiconductor layer 19 and the transparent conductive layer 23, and the transparent conductive layer 23 is arranged on the side of the doped semiconductor layer 19 away from the semiconductor substrate 11, the non-pyramid texture structure 15 and the quasi-cone-shaped protrusion structure 16 are both formed on the side of the transparent conductive layer 23 away from the semiconductor substrate 11. In addition, the formation position of the doped semiconductor layer 19 in the above-mentioned solar cell, as well as the materials of the surface passivation layer, the anti-reflection layer, the transparent conductive layer 23 and the doped semiconductor layer 19 can be referred to the above text, and will not be repeated here.

[0062] It should be noted that, when the solar cell provided in the embodiment of the present invention is a double-sided contact cell, the doped semiconductor layer in the same passivation layer is an N-type doped semiconductor layer or a P-type doped semiconductor layer. Fig.10 As shown, along the direction parallel to the target surface, the doped semiconductor layer in the passivation layer includes a first doped semiconductor portion 17 and a second doped semiconductor portion 18 that are alternately distributed; the first doped semiconductor portion 17 and the second doped semiconductor portion 18 have opposite conductivity types, and at least a portion of the first doped semiconductor portion 17 and at least a portion of the second doped semiconductor portion 18 are spaced apart. It can be understood that one of the first doped semiconductor portion 17 and the second doped semiconductor portion 18 is an N-type doped semiconductor portion, and the other is a P-type doped semiconductor portion. Secondly, at least a portion of the first doped semiconductor portion 17 and at least a portion of the second doped semiconductor portion 18 can be spaced apart along the direction parallel to the target surface, or can be spaced apart along the thickness direction of the semiconductor substrate by a dielectric layer of insulating material such as silicon oxide, silicon nitride or silicon oxynitride.

[0063] In addition, when the doped semiconductor layer is disposed on the target surface, as Fig. 9 As shown, the doped semiconductor layer 19 may be in direct contact with the semiconductor substrate 11; or Fig.10 As shown, the solar cell may further include an interface passivation layer 20 located between the semiconductor substrate 11 and the doped semiconductor layer. The material and thickness of the interface passivation layer 20 may be determined according to the material of the doped semiconductor layer, and are not specifically limited here. For example, when the doped semiconductor layer includes a doped polycrystalline silicon layer, the interface passivation layer is a tunneling oxide layer. For another example, when the doped semiconductor layer includes a doped amorphous silicon layer, the interface passivation layer is an intrinsic amorphous silicon layer.

[0064] In terms of surface morphology, the surface of the passivation layer facing away from the semiconductor substrate has a plurality of non-pyramid-shaped texture structures and a plurality of discretely distributed conical protrusion structures. The specific type and size of the non-pyramid-shaped texture structures can be determined according to the actual application scenario, as long as they can be applied to the solar cell provided in the embodiment of the present invention.

[0065] Exemplarily, the non-pyramid texture structure may include a linear protrusion structure. In this case, compared with the pyramid texture structure, the linear protrusion structure has a smaller degree of undulation, ensuring that the side of the passivation layer away from the semiconductor substrate is macroscopically flat, thereby improving the passivation effect of the passivation layer. Secondly, the surface of the linear protrusion structure may have a conical protrusion junction. At this time, the presence of the conical protrusion structure makes the surface of the linear protrusion structure originally having an undulating morphology superimposed with the degree of undulation of the conical protrusion structure, which is conducive to further increasing the microscopic surface roughness of the side of the passivation layer away from the semiconductor substrate, and is conducive to further increasing the specific surface area of ​​the above-mentioned doped semiconductor layer, thereby increasing the contact area between the doped semiconductor layer and the electrode, further improving the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is conducive to improving the conversion efficiency of the solar cell.

[0066] For example, Figure 5 As shown, the non-pyramid texture structure 15 may include a base-like texture structure. The application principle of the beneficial effect in this case can refer to the application principle of the beneficial effect of the non-pyramid texture structure 15 including the linear protrusion structure described above, which will not be repeated here. Figure 5 As shown, the surface of the tower-like texture structure may also have a cone-like protrusion structure 16 to further increase the microscopic surface roughness of the side of the passivation layer 14 away from the semiconductor substrate 11, which is conducive to further increasing the specific surface area of ​​the above-mentioned doped semiconductor layer, thereby increasing the contact area between the doped semiconductor layer and the electrode, further improving the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is conducive to improving the conversion efficiency of the solar cell. Among them, the above-mentioned tower-like texture structure can be a tower-like texture structure with a regular polygonal bottom surface, or a tower-like texture structure with an irregular arc-shaped contour on the bottom surface.

[0067] Exemplarily, the non-pyramid-type texture structure may include a convex platform structure remaining after the top of the pyramid-type structure is eliminated. The application principle of the beneficial effect in this case can refer to the application principle of the beneficial effect of the non-pyramid-type texture structure including the linear convex structure described above, which will not be repeated here. Secondly, the surface of the convex platform structure may also have a conical convex structure to further increase the microscopic surface roughness of the side of the passivation layer away from the semiconductor substrate.

[0068] As for the above-mentioned cone-like convex structure, the size of the cone-like convex structure will affect the surface roughness of the side of the passivation layer away from the semiconductor substrate. Specifically, when other factors are the same, the smaller the spacing between two adjacent cone-like convex structures, the greater the distribution density of the cone-like convex structure on the side of the passivation layer away from the semiconductor substrate, so that the surface roughness of the passivation layer away from the semiconductor substrate is greater. On the contrary, the larger the spacing between two adjacent cone-like convex structures, the smaller the distribution density of the cone-like convex structure on the side of the passivation layer away from the semiconductor substrate, so that the surface roughness of the passivation layer away from the semiconductor substrate is smaller. Secondly, when other factors are the same, the height of the cone-like convex structure is proportional to its own undulation degree and proportional to the surface roughness of the passivation layer away from the semiconductor substrate. In addition, when other factors are the same, the smaller the diameter of the cone-like convex structure, the smaller the angle corresponding to its smooth top, so that it is similar to a "thin and tall" type, so that the surface undulation degree is larger. On the contrary, the larger the diameter of the conical protrusion structure, the larger the angle corresponding to the rounded top, making it similar to a "short and fat" type, so that the surface undulation is smaller. Based on this, the surface roughness requirements of the passivation layer on the side away from the semiconductor substrate can be determined according to the actual application scenario, and no specific limitation is made here.

[0069] In actual application, the solar cell further includes a collector electrode disposed on the side of the passivation layer away from the semiconductor substrate, for collecting and conducting carriers in the doped semiconductor layer. The presence of the above-mentioned quasi-conical protrusion structure is conducive to increasing the contact area between the collector electrode and the doped semiconductor layer, as well as the attachment and shaping of the collector electrode on the doped semiconductor layer. Based on this, the spacing of the quasi-conical protrusion structure can be determined according to the size of the collector electrode in the actual application scenario, as well as the requirements for the contact performance and shaping of the collector electrode.

[0070] Exemplarily, the width of the collector electrode is greater than ten times the distance between two adjacent conical protrusion structures. In this case, it is possible to prevent the surface roughness of the passivation layer on the side away from the semiconductor substrate from being too small due to the large distance, which is conducive to further increasing the specific surface area of ​​the above-mentioned doped semiconductor layer, thereby increasing the contact area between the doped semiconductor layer and the electrode, further improving the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is conducive to improving the conversion efficiency of the solar cell.

[0071] As for the specific spacing between two adjacent quasi-conical convex structures, for example, the spacing between two adjacent quasi-conical convex structures can be greater than or equal to 0.5 μm and less than or equal to 3 μm. For example, the spacing between two adjacent quasi-conical convex structures can be 0.5 μm, 0.06 μm, 0.08 μm, 1 μm, 1.2 μm, 1.4 μm, 1.8 μm, 2 μm, 2.4 μm, 2.8 μm or 3 μm, etc. In this case, based on this, when the spacing between two adjacent quasi-conical convex structures is within the above range, it can prevent the surface roughness of the passivation layer away from the semiconductor substrate from being too small due to the spacing being too small, ensuring that the target surface of the semiconductor substrate has a relatively flat surface, further improving the formation quality of the passivation layer on the target surface, and facilitating the increase of the film thickness of the passivation layer, which is conducive to further improving the passivation effect of the passivation layer on the semiconductor substrate. In addition, it can also prevent the surface roughness of the passivation layer on the side facing away from the semiconductor substrate from being smaller due to the large spacing, which is beneficial to further increase the specific surface area of ​​the above-mentioned doped semiconductor layer, and then increase the contact area between the doped semiconductor layer and the electrode, further improve the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is beneficial to improve the conversion efficiency of the solar cell.

[0072] Exemplarily, the height of the above-mentioned cone-like protrusion structure can be greater than or equal to 0.2 μm and less than or equal to the height of the non-pyramid-shaped texture structure. In this case, based on this, when the height of the cone-like protrusion structure is within the above-mentioned range, it is beneficial to prevent the surface roughness of the passivation layer away from the semiconductor substrate side from being too small due to the height being too small, and it is beneficial to further increase the specific surface area of ​​the above-mentioned doped semiconductor layer, thereby increasing the contact area between the doped semiconductor layer and the electrode, and further improving the contact performance between the doped semiconductor layer and the electrode, as well as the adhesion and shaping of the electrode on the doped semiconductor layer. In addition, it is also possible to prevent the surface roughness of the passivation layer away from the semiconductor substrate side from being too large due to the height being too large, ensuring that the target surface of the semiconductor substrate on which the passivation layer is formed has a relatively flat surface, further improving the formation quality of the passivation layer on the target surface, and facilitating the increase of the film thickness of the passivation layer, which is beneficial to further improve the passivation effect of the passivation layer on the semiconductor substrate, and is beneficial to improving the conversion efficiency of the solar cell.

[0073] Exemplarily, the height of the quasi-cone-shaped protrusion structure is less than or equal to 0.5 μm. In this case, the height of the quasi-cone-shaped protrusion structure can be prevented from being too large, and its beneficial effects can be referred to above, which will not be repeated here.

[0074] For example, the height of the cone-like protrusion structure may be 0.2 μm, 0.25 μm, 0.3 μm, 0.35 μm, 0.4 μm, 0.45 μm or 0.5 μm, etc.

[0075] Specifically, Figure 7 As shown, the height of the above-mentioned cone-like protrusion structure 16 can be less than the bottom diameter of the cone-like protrusion structure 16. In this case, compared with the "thin and tall" cone-like protrusion structure 16 whose height is less than the bottom diameter of the cone-like protrusion structure 16, when the height of the cone-like protrusion structure 16 is less than the bottom diameter of the cone-like protrusion structure 16, the cone-like protrusion structure 16 is "short and fat", ensuring that the side of the passivation layer away from the semiconductor substrate has a relatively small degree of undulation, ensuring that the side of the passivation layer away from the semiconductor substrate and the target surface of the semiconductor substrate are macroscopically flat surfaces, further improving the formation quality of the passivation layer on the target surface, and facilitating the increase of the film thickness of the passivation layer, thereby facilitating the passivation effect of the passivation layer on the semiconductor substrate and improving the conversion efficiency of the solar cell. Of course, there may also be at least one cone-like protrusion structure 16 whose height is greater than or equal to the width of the cone-like protrusion structure 16.

[0076] Exemplarily, the diameter of the above-mentioned cone-like protrusion structure can be greater than or equal to 0.5μm and less than or equal to 0.65μm. For example, the diameter of the cone-like protrusion structure can be 0.5μm, 0.51μm, 0.53μm, 0.55μm, 0.58μm, 0.6μm, 0.62μm or 0.65μm, etc. In this case, based on this, when the diameter of the cone-like protrusion structure is within the above range, it is beneficial to prevent the surface roughness of the passivation layer away from the semiconductor substrate from being larger due to the smaller diameter, ensure that the target surface of the semiconductor substrate has a relatively flat surface, further improve the formation quality of the passivation layer on the target surface, and help increase the film thickness of the passivation layer, which is beneficial to further improve the passivation effect of the passivation layer on the semiconductor substrate. In addition, it can also prevent the surface roughness of the passivation layer on the side facing away from the semiconductor substrate from being smaller due to the larger diameter, which is beneficial to further increase the specific surface area of ​​the above-mentioned doped semiconductor layer, and then increase the contact area between the doped semiconductor layer and the electrode, further improve the contact performance between the doped semiconductor layer and the electrode, and the adhesion and shaping of the electrode on the doped semiconductor layer, which is beneficial to improve the conversion efficiency of the solar cell.

[0077] Specifically, the heights and bottom diameters of the different types of conical protrusion structures on the side of the passivation layer facing away from the semiconductor substrate, as well as the spacings between different pairs of conical protrusion structures may be substantially the same.

[0078] Alternatively, the heights and bottom diameters of the different types of conical protrusions on the side of the passivation layer facing away from the semiconductor substrate, as well as the spacing between different pairs of conical protrusions, may also be different. In this case, as mentioned above, because the height and bottom diameter of the conical protrusions, as well as the spacing between different pairs of conical protrusions, will affect the surface roughness of the side of the passivation layer facing away from the semiconductor substrate, the height and bottom diameter of the conical protrusions in different areas of the passivation layer facing away from the semiconductor substrate, as well as the spacing between different pairs of conical protrusions, can be determined based on the different requirements for the surface roughness of different areas of the passivation layer in the actual application scenario, and no specific limitation is made here.

[0079] Exemplarily, in the case where the solar cell provided in the embodiment of the present invention is a double-sided contact cell, the area corresponding to the collector electrode on the side of the passivation layer facing away from the semiconductor substrate is the first area, and the remaining area is the second area. The height and / or bottom diameter of the cone-like protrusion structure on the surface of the first area can be respectively greater than the height and / or bottom diameter of the cone-like protrusion structure on the surface of the second area, and the spacing between two adjacent cone-like protrusion structures on the surface of the first area can be smaller than the spacing between two adjacent cone-like protrusion structures on the surface of the second area.

[0080] Exemplarily, in the case where only one of the first and second surfaces is the target surface, along the direction parallel to the target surface, the passivation layer includes a first doped semiconductor portion and a second doped semiconductor portion that are alternately distributed. The conductivity types of the first doped semiconductor portion and the second doped semiconductor portion are opposite, and at least a portion of the first doped semiconductor portion and at least a portion of the second doped semiconductor portion are spaced apart. In the above case, the side surface of the passivation layer corresponding to the first doped semiconductor portion that is away from the semiconductor substrate is defined as the first sub-surface, and the side surface of the passivation layer corresponding to the second doped semiconductor portion that is away from the semiconductor substrate is defined as the second sub-surface. In addition, both the first sub-surface and the second sub-surface have a conical convex structure. In this case, the spacing between two adjacent conical convex structures of the first sub-surface may be different from the spacing between two adjacent conical convex structures of the second sub-surface; and / or, the height of the conical convex structure of the first sub-surface may be different from the height of the conical convex structure of the second sub-surface; and / or, the bottom diameter of the conical convex structure of the first sub-surface may be different from the bottom diameter of the conical convex structure of the second sub-surface.

[0081] In the case of adopting the above technical solution, as described above, when the spacing between adjacent quasi-conical protrusion structures is different, the surface roughness of the passivation layer on the side away from the semiconductor substrate is different. Based on this, when the spacing between two adjacent quasi-conical protrusion structures on the first sub-surface is different from the spacing between two adjacent quasi-conical protrusion structures on the second sub-surface, the spacing, height and bottom diameter of the quasi-conical protrusion structures can be set according to the requirements for different passivation effects of the first doped semiconductor part and the second doped semiconductor part in the actual application scenario, and the requirements for the contact performance between the two and the corresponding electrodes, so that the two parts of the passivation layer corresponding to the first doped semiconductor part and the second doped semiconductor part respectively have different passivation effects on the semiconductor substrate, and are conducive to making the first doped semiconductor part and the second doped semiconductor part have different surface morphologies, thereby facilitating the reduction of the passivation difference between the two parts of the passivation layer corresponding to the first doped semiconductor part and the second doped semiconductor part respectively, and facilitating the reduction of the difference in contact performance between the first doped semiconductor part and the second doped semiconductor part and the corresponding electrodes respectively. Secondly, the application principle of the beneficial effect of the height and / or bottom diameter of the cone-like protrusion structure on the first sub-surface and the second sub-surface can be found in the above text and will not be repeated here.

[0082] Among them, the specific conductivity types of the above-mentioned first doped semiconductor part and the second doped semiconductor part, and the size relationship of the cone-shaped protrusion structure sizes of the first sub-surface and the second sub-surface under the corresponding conductivity type can be set according to actual needs, as long as it can help to reduce the passivation difference between the two parts of the passivation layer corresponding to the first doped semiconductor part and the second doped semiconductor part, and help to reduce the difference in contact performance between the first doped semiconductor part and the second doped semiconductor part and the corresponding electrodes.

[0083] For example: when the conductivity type of the first doped semiconductor portion is P-type, the spacing between two adjacent cone-like protrusion structures on the first sub-surface may be greater than the spacing between two adjacent cone-like protrusion structures on the second sub-surface; or, the top angle of the cone-like protrusion structure on the first sub-surface may be smaller than the top angle of the cone-like protrusion structure on the second sub-surface.

[0084] In the case of adopting the above technical solution, due to the limitation of doping solid concentration and doping difficulty, the dopant concentration of the dopant in the N-type doped semiconductor part is greater than the doping concentration of the dopant in the P-type doped semiconductor part, and the passivation characteristics of the P-type doped semiconductor part are relatively poor. Based on this, when the conductivity type of the first doped semiconductor part is P-type, and the first sub-surface corresponding to the first doped semiconductor part on the side of the passivation layer away from the semiconductor substrate has a spacing between two adjacent cone-like protrusion structures, which is greater than the spacing between two adjacent cone-like protrusion structures on the second sub-surface (the surface of the region corresponding to the N-type doped semiconductor part on the side of the passivation layer away from the semiconductor substrate), the first sub-surface has a relatively small surface roughness, so that the first sub-surface is relatively flat in macroscopic terms, and accordingly, the portion corresponding to the first sub-surface in the target surface of the semiconductor substrate is also likely to be a relatively flat surface, which is conducive to improving the formation quality and film thickness of the P-type doped semiconductor part on the target surface, and further conducive to improving the passivation effect of the P-type doped semiconductor part on the semiconductor substrate. While under the condition that other factors are the same, when the apex angle of the cone-like protrusion structure on the first sub-surface is smaller than the apex angle of the cone-like protrusion structure on the second sub-surface, the expansion degree of the two relative side edges constituting the apex angle is smaller. At this time, the bottom surface of the cone-like protrusion structure on the first sub-surface is conducive to making the distribution density of the cone-like protrusion structure on the first sub-surface sparse, thereby reducing the surface roughness of the first sub-surface, which is conducive to improving the passivation effect of the P-type doped semiconductor part on the semiconductor substrate, reducing the difference in the passivation effects of the P-type doped semiconductor part and the N-type doped semiconductor part on the semiconductor substrate respectively, and further improving the conversion efficiency of the solar cell.

[0085] Exemplarily, when the conductivity type of the first doped semiconductor portion is P-type, the bottom diameter of the cone-like protrusion structure on the first sub-surface may be smaller than the bottom diameter of the cone-like protrusion structure on the second sub-surface; or, the height of the cone-like protrusion structure on the first sub-surface may be greater than the height of the cone-like protrusion structure on the second sub-surface. The application principle of the beneficial effect in this case can refer to the application principle of the beneficial effect of the spacing between two adjacent cone-like protrusion structures on the first sub-surface being greater than the spacing between two adjacent cone-like protrusion structures on the second sub-surface as described above, which will not be repeated here.

[0086] In addition, in the actual application process, the distribution density of the cone-like protrusion structure in different areas of the passivation layer away from the semiconductor substrate side may be roughly the same or different. Alternatively, among the different areas of the passivation layer away from the semiconductor substrate side, only some areas are distributed with cone-like protrusion structures, while the remaining areas do not have cone-like protrusion structures. For example: only one of the above-mentioned first sub-surface and the second sub-surface has a cone-like protrusion structure. In this case, the first sub-surface without the cone-like protrusion structure is used as an example for explanation. When other factors are the same, the second sub-surface having the cone-like protrusion structure has a relatively larger surface roughness at the microscopic level compared with the first sub-surface without the cone-like protrusion structure. Whether the first sub-surface and the second sub-surface have a conical protrusion structure can be respectively set according to the requirements for different passivation effects of the first doped semiconductor part and the second doped semiconductor part in the actual application scenario, and the requirements for the contact performance between the two and the corresponding electrodes, so that the two parts of the passivation layer corresponding to the first doped semiconductor part and the second doped semiconductor part respectively have different passivation effects on the semiconductor substrate, and the first doped semiconductor part and the second doped semiconductor part have different surface morphologies, which is conducive to reducing the passivation difference between the two parts of the passivation layer corresponding to the first doped semiconductor part and the second doped semiconductor part respectively, and is conducive to reducing the difference in contact performance between the first doped semiconductor part and the second doped semiconductor part and the corresponding electrodes.

[0087] Among them, the specific conductivity types of the above-mentioned first doped semiconductor part and the second doped semiconductor part can be set according to actual needs, as long as it can help reduce the passivation difference between the two parts of the passivation layer corresponding to the first doped semiconductor part and the second doped semiconductor part, and help reduce the difference in contact performance between the first doped semiconductor part and the second doped semiconductor part and the corresponding electrodes.

[0088] For example, when the conductivity type of the first doped semiconductor portion is P-type, only the first sub-surface has a cone-like protrusion structure in the first sub-surface and the second sub-surface. In this case, it is beneficial to reduce the difference in contact performance between the first doped semiconductor portion and the second doped semiconductor portion and the corresponding electrodes, thereby improving the contact performance.

[0089] In one example, the surface of the passivation layer facing away from the semiconductor substrate has a first area and a second area that do not overlap each other. In addition, the collector electrode included in the solar cell is located on at least part of the first area. The non-pyramid texture structure and the cone-like convex structure are both distributed in the first area. The surface of the second area has a densely distributed pyramid texture structure. Among them, the height of the pyramid texture structure is greater than the height of the cone-like convex structure, and / or the bottom side length of the pyramid texture structure is greater than the bottom diameter of the cone-like convex structure. In this case, as described above, compared with the surface formed with the pyramid texture structure, the surface with the non-pyramid texture structure and the cone-like convex structure is macroscopically flat; but compared with the surface with only the non-pyramid texture structure such as the tower base texture structure, the surface with the non-pyramid texture structure and the cone-like convex structure has a relatively large surface roughness at the microscopic level. In addition, the collector electrode included in the solar cell needs to be in electrical contact with the doped semiconductor layer to collect and export carriers. Based on this, on the side of the passivation layer away from the semiconductor substrate, a non-pyramid texture structure with a small degree of undulation and a cone-like protrusion structure are distributed on the surface of at least the first region corresponding to the collector electrode, so that the surface of the first region and the surface of the region corresponding to the first region in the target surface are relatively flat, which is conducive to improving the formation quality of the doped semiconductor layer on the surface of the target surface corresponding to the first region, and increasing the film thickness of the doped semiconductor layer, and improving the passivation effect of the doped semiconductor layer; and the presence of the cone-like protrusion structure on the first region is also conducive to increasing the contact area between the doped semiconductor layer and the collector electrode, improving the contact performance between the doped semiconductor layer and the collector electrode, and the attachment and shaping of the collector electrode on the doped semiconductor layer. In addition, the surface of the second region of the passivation layer has a densely distributed pyramid texture structure, which can improve the surface light trapping effect of the second region, which is conducive to improving the conversion efficiency of solar cells.

[0090] Specifically, the embodiment of the present invention does not specifically limit the size and distribution density of the pyramid-shaped texture structure, as long as it can be applied to the solar cell provided by the embodiment of the present invention.

[0091] In addition, from the distribution of the first area and the second area, the first area and the second area may not be coplanar, in which case the first surface and the second surface of the semiconductor substrate are both target surfaces. The first area may be a passivation layer formed on the first surface, which is a local area or the entire area on the side away from the semiconductor substrate; in this case, the second area is a passivation layer formed on the second surface, which is a local area or the entire area on the side away from the semiconductor substrate. In this case, the solar cell is a double-sided contact cell. The second surface may correspond to the front side of the solar cell, in which case the presence of the pyramid-shaped texture structure can improve the light trapping effect on the front side of the solar cell and improve the conversion efficiency of the solar cell.

[0092] Alternatively, the first region and the second region may also be coplanar, in which case the first region and the second region may be two non-overlapping local regions on the side of the same passivation layer facing away from the semiconductor substrate. In this case, the solar cell may be a double-sided contact cell or a back-contact cell. In this case, the division between the first region and the second region may be determined based on the specific structure of the solar cell, the distribution position of the collector electrode on the first region, and actual needs.

[0093] As for the formation range of the collector electrode, the collector electrode can be located on the entire first area. At this time, the first area on the surface of the side of the passivation layer away from the semiconductor substrate is the electrode area. No collector electrode is set on the second area (that is, the second area is a non-electrode area). In this case, the second area can be any area on the surface of the side of the passivation layer away from the semiconductor substrate that does not correspond to the collector electrode. It should be noted that this situation can be applied not only to back-contact batteries, but also to double-sided contact batteries. One side surface of the above-mentioned semiconductor substrate is the light-receiving surface of the solar cell, which can be the front of the battery or the back of the battery.

[0094] Alternatively, the collector electrode may also be located only on part of the first region. In this case, the division between the first region and the second region can be set according to the specific structure of the solar cell and the actual needs, and is not specifically limited here. Exemplarily, the part of the passivation layer corresponding to the doped semiconductor layer facing away from the semiconductor substrate is the first region, and the part of the passivation layer where the doped semiconductor layer is not provided is the second region. For example: when the solar cell is a back contact cell, the part of the passivation layer corresponding to the N-type doped semiconductor part or the P-type doped semiconductor part facing away from the semiconductor substrate is the first region, and the part of the passivation layer corresponding to the interval area between the N-type doped semiconductor part and the P-type doped semiconductor part facing away from the semiconductor substrate is the second region. For another example: when the solar cell is a double-sided contact cell, a doped semiconductor layer distributed in the form of polycrystalline silicon fingers (i.e., poly fingers) is formed on the target surface. At this time, the part of the passivation layer corresponding to the polycrystalline silicon fingers is the first region, which can correspond to the electrode region, and the part of the passivation layer not corresponding to the polycrystalline silicon fingers is the second region, which can correspond to the non-electrode region.

[0095] In a second aspect, an embodiment of the present invention provides a photovoltaic module, which includes the solar cell provided by the first aspect and various implementations thereof.

[0096] The beneficial effects of the second aspect and its various implementations in the embodiments of the present invention can be analyzed with reference to the beneficial effects of the first aspect and its various implementations, and will not be repeated here.

[0097] In the above description, the technical details of the patterning and etching of each layer are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above. In addition, although the various embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage.

[0098] The embodiments of the present invention are described above. However, these embodiments are only for a clearer description and are not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims and their equivalents. Without departing from the scope of the present invention, a person skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A solar cell, characterized in that: include: A semiconductor substrate having a first surface and a second surface opposite to each other; at least one of the first surface and the second surface is a target surface; A passivation layer, disposed on the target surface; The surface of the passivation layer on one side facing away from the semiconductor substrate has a plurality of non-pyramid texture structures and a plurality of discretely distributed cone-like protrusion structures.

2. The solar cell according to claim 1, characterized in that: The distance between two adjacent cone-shaped protrusion structures is greater than or equal to 0.5 μm and less than or equal to 3 μm; And / or, the solar cell further comprises a collector electrode arranged on a side of the passivation layer away from the semiconductor substrate; a width of the collector electrode is greater than ten times a distance between two adjacent cone-like protrusion structures.

3. The solar cell according to claim 1, characterized in that The height of the quasi-conical protrusion structure is greater than or equal to 0.2 μm and less than or equal to the height of the non-pyramid texture structure; And / or, the height of the cone-like protrusion structure is less than or equal to 0.5 μm.

4. The solar cell according to claim 1, characterized in that The height of the cone-like protrusion structure is smaller than the bottom diameter of the cone-like protrusion structure; And / or, the diameter of the cone-like protrusion structure is greater than or equal to 0.5 μm and less than or equal to 0.65 μm.

5. The solar cell according to claim 1, characterized in that: The non-pyramid texture structure includes a linear protrusion structure, and the surface of the linear protrusion structure has the quasi-cone-shaped protrusion structure.

6. The solar cell according to claim 1, characterized in that The non-pyramid texture structure includes a tower base-like texture structure, and the surface of the tower base-like texture structure has the cone-like protrusion structure.

7. The solar cell according to claim 1, characterized in that Only one of the first surface and the second surface is a target surface; along a direction parallel to the target surface, the passivation layer includes first doped semiconductor portions and second doped semiconductor portions that are alternately distributed; the first doped semiconductor portions and the second doped semiconductor portions have opposite conductivity types, and at least a portion of the first doped semiconductor portions and at least a portion of the second doped semiconductor portions are spaced apart; The surface of the passivation layer corresponding to the first doped semiconductor portion and facing away from the semiconductor substrate is a first sub-surface, and the surface of the passivation layer corresponding to the second doped semiconductor portion and facing away from the semiconductor substrate is a second sub-surface; The spacing between two adjacent cone-like protrusion structures on the first sub-surface is different from the spacing between two adjacent cone-like protrusion structures on the second sub-surface; or, only one of the first sub-surface and the second sub-surface has the cone-like protrusion structure.

8. The solar cell according to claim 7, characterized in that: In the case where both the first sub-surface and the second sub-surface have the cone-like protrusion structure, and the conductivity type of the first doped semiconductor portion is P type, The spacing between two adjacent cone-like protrusion structures on the first sub-surface is greater than the spacing between two adjacent cone-like protrusion structures on the second sub-surface; or the top angle of the cone-like protrusion structure on the first sub-surface is smaller than the top angle of the cone-like protrusion structure on the second sub-surface.

9. The solar cell according to claim 7, characterized in that: In the case where both the first sub-surface and the second sub-surface have the cone-like protrusion structure, and the conductivity type of the first doped semiconductor portion is P type, The bottom diameter of the cone-like protrusion structure on the first sub-surface is smaller than the bottom diameter of the cone-like protrusion structure on the second sub-surface; or, the height of the cone-like protrusion structure on the first sub-surface is greater than the height of the cone-like protrusion structure on the second sub-surface.

10. The solar cell according to claim 1, characterized in that: The surface of the passivation layer on one side away from the semiconductor substrate has a first area and a second area that do not overlap each other; the solar cell also includes a collector electrode arranged on the side of the passivation layer away from the semiconductor substrate, and the collector electrode is located on at least part of the first area; the non-pyramid texture structure and the quasi-conical protrusion structure are both distributed in the first area; the surface of the second area has a closely distributed pyramid texture structure; Wherein, the height of the pyramid-shaped texture structure is greater than the height of the quasi-cone-shaped protrusion structure, and / or the bottom side length of the pyramid-shaped texture structure is greater than the bottom diameter of the quasi-cone-shaped protrusion structure.

11. A photovoltaic module, characterized in that: The invention comprises a solar cell as claimed in any one of claims 1 to 10.

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