Solar cell and method of manufacturing the same, stacked cell, photovoltaic module

Abstract

This application relates to the field of solar cell technology, and in particular to solar cells and their fabrication methods, tandem solar cells, and photovoltaic modules. A solar cell includes a substrate, a doped region, a first passivation layer, and a second passivation layer. The substrate has a first surface and a second surface disposed opposite to each other. The first surface is divided into alternating first and second regions. The first surface also includes a third region located at the edge of the first surface and adjacent to the second region. The distance between the first region and the second surface is H1, the distance between the second region and the second surface is H2, and the distance between the third region and the second surface is H3, where H1 > H2 and H2 > H3. The doped region is located in the first region. The first passivation layer is located on the side of the doped region facing away from the second surface, on the second region, and on the third region. The second passivation layer is located on the side of the first passivation layer on the third region facing away from the first surface. This improves the performance of the solar cell.

Description

Technical Field

[0001] This application relates to the field of solar cell technology, and in particular to solar cells and their manufacturing methods, tandem cells, and photovoltaic modules. Background Technology

[0002] A solar cell is a device that converts solar energy into electrical energy. Specifically, a solar cell uses the photovoltaic principle to generate charge carriers, and then uses electrodes to extract these carriers, thus facilitating the efficient use of electrical energy. However, the performance of solar cells needs further improvement. Summary of the Invention

[0003] Therefore, it is necessary to provide a solar cell and its manufacturing method, a tandem cell, and a photovoltaic module to improve the performance of solar cells.

[0004] According to one aspect of this application, an embodiment of this application provides a solar cell, including a substrate, a doped region, a first passivation layer, and a second passivation layer. The substrate has a first surface and a second surface disposed opposite to each other; the first surface is divided into alternating first regions and second regions. The first surface is further divided into a third region, which is located at the edge of the first surface and adjacent to the second region. The distance between the first region and the second surface is H1, the distance between the second region and the second surface is H2, and the distance between the third region and the second surface is H3, where H1 > H2 and H2 > H3. The doped region is disposed in the first region. The first passivation layer is disposed on the side of the doped region opposite to the second surface, on the second region, and on the third region. The second passivation layer is disposed on the side of the first passivation layer located on the third region opposite to the first surface.

[0005] In some embodiments, a second region adjacent to the third region is defined as the target region; the second passivation layer is also disposed on the side of the first passivation layer located on the target region that is opposite to the first surface, and the second passivation layer located on the target region and the second passivation layer located on the third region are connected.

[0006] In some embodiments, the substrate further has a side surface connecting the first surface and the second surface, and a second passivation layer is further disposed on the side surface.

[0007] In some embodiments, the doping element in the doped region is defined as the first doping element. The doping concentration of the first doping element in the doped region is N1, the doping concentration of the first doping element in the second region is N2, and the doping concentration of the first doping element in the third region is N3, where N1 > N2, N1 > N3, and N2 ≥ N3.

[0008] In some embodiments, the doping type of the first dopant element is the same as the doping type of the substrate; N1 is 5 × 10⁻⁶. 19 cm -3 Up to 5×10 20 cm-3 .

[0009] In some embodiments, N2 is 1 × 10 16 cm -3 Up to 1×10 19 cm -3 N3 is 1×10 15 cm -3 Up to 1×10 16 cm -3 .

[0010] In some embodiments, the doping type of the first dopant element is different from the doping type of the substrate; N1 is 5 × 10 15 cm -3 Up to 5×10 16 cm -3 .

[0011] In some embodiments, N2 is 1 × 10 16 cm -3 Up to 1×10 18 cm -3 .

[0012] In some embodiments, the third region includes a first side connecting to the corresponding second region and a second side opposite to the first side and away from the second region; the third region is inclined relative to the corresponding second region from the first side to the second side.

[0013] In some embodiments, the third region includes a first sub-region and a second sub-region connected together, with the side of the first sub-region away from the second sub-region connected to the corresponding second region; the first sub-region and the second sub-region define a recess.

[0014] In some embodiments, a first pyramid-shaped structure is provided on the third region, and a second pyramid-shaped structure is provided on the second region.

[0015] In some embodiments, the height of the first pyramidal structure is less than or equal to the height of the second pyramidal structure; and / or, the one-dimensional dimension of the first pyramidal structure is less than or equal to the one-dimensional dimension of the second pyramidal structure; and / or, the gap between two adjacent first pyramidal structures is less than or equal to the gap between two adjacent second pyramidal structures.

[0016] In some embodiments, the height of the first pyramidal structure is 0.5 μm to 1.5 μm, and the height of the second pyramidal structure is 1.5 μm to 2.5 μm; and / or, the one-dimensional dimension of the first pyramidal structure is 2 μm to 5 μm, and the one-dimensional dimension of the second pyramidal structure is 4 μm to 6 μm; and / or, the gap between two adjacent first pyramidal structures is 1 μm to 3 μm, and the gap between two adjacent second pyramidal structures is 2 μm to 4 μm.

[0017] In some embodiments, the third region includes a first sub-region and a second sub-region, the first sub-region connecting the second region and the second sub-region, and the first sub-region and the second sub-region defining a recess; the first pyramidal structure includes a first sub-pyramidal structure disposed on the first sub-region and a second sub-pyramidal structure disposed on the second sub-region.

[0018] In some embodiments, the height of the first sub-pyramid structure is greater than or equal to the height of the second sub-pyramid structure; and / or, the one-dimensional dimension of the first sub-pyramid structure is greater than or equal to the one-dimensional dimension of the second sub-pyramid structure; and / or, the gap between two adjacent first sub-pyramid structures is greater than or equal to the gap between two adjacent second sub-pyramid structures.

[0019] In some embodiments, the height of the first sub-pyramid structure is 0.8 μm to 1.5 μm, and the height of the second sub-pyramid structure is 0.5 μm to 1 μm; and / or, the one-dimensional dimension of the first sub-pyramid structure is 3 μm to 5 μm, and the one-dimensional dimension of the second sub-pyramid structure is 2 μm to 4 μm; and / or, the gap between two adjacent first sub-pyramid structures is 1.5 μm to 3 μm, and the gap between two adjacent second sub-pyramid structures is 1 μm to 2 μm.

[0020] According to another aspect of this application, an embodiment of this application provides a method for manufacturing a solar cell, used to manufacture the solar cell in any of the above embodiments. The method for manufacturing a solar cell includes: providing a first intermediate for a solar cell, the first intermediate for a solar cell including a substrate, a doped region and a first passivation layer; performing a first laser treatment on the first intermediate for a solar cell to form a groove; cutting the first intermediate for a solar cell along the groove to obtain at least two second intermediates for a solar cell, the second intermediate for a solar cell including a first surface, a second surface and a third surface connecting the first surface and the second surface; and depositing a second passivation layer on the third surface of the second intermediate for a solar cell to form a solar cell.

[0021] In some embodiments, the first intermediate of the solar cell is cut by a laser cutting process; the laser parameters of the laser cutting process meet at least one of the following: the laser is a pulsed red nanosecond laser; the laser pulse width is 5ps to 15ps; the laser frequency is 33kHz to 200kHz; the laser power is 1200W to 2000W; and the laser scanning speed is 120mm / s to 400mm / s.

[0022] According to another aspect of this application, an embodiment of this application provides a tandem battery, including a bottom battery and a top battery stacked on the bottom battery; wherein the bottom battery includes a solar cell as described in any of the above embodiments; or, the bottom battery includes a solar cell manufactured by the method for manufacturing solar cells as described in any of the above embodiments.

[0023] According to another aspect of this application, embodiments of this application provide a photovoltaic module, including the solar cell in any of the above embodiments; or, a solar cell manufactured by the method for manufacturing the solar cell in any of the above embodiments; or a tandem cell in any of the above embodiments.

[0024] In the aforementioned solar cells, their fabrication methods, tandem cells, and photovoltaic modules, on the one hand, because H1 > H2 and H2 > H3, the morphology of the first surface, consisting of a first region, a second region, and a third region, descends sequentially, making the morphology of the first surface more gentle. This reduces the internal stress of the film layer during the formation of the first passivation layer, improving its adhesion stability. The more convex first region of the first surface facilitates contact between the doped region and the subsequent electrode structure. The downward slope of the third region at the edge of the first surface increases the lateral spacing between the conductive doped structures on the first and second sides, enlarging the lateral leakage channel at the edge and thus helping to suppress edge leakage. Simultaneously, since the region adjacent to the third region of the first surface is the second region, which lacks a doped region, cutting damage is reduced during the process of forming the third region and the solar cell, thereby improving the performance of the solar cell. On the other hand, the risk of cutting damage at the edge of the substrate can lead to numerous dangling bonds and interface defects, and may also result in uneven thickness and incomplete coverage of the first passivation layer at the edge. By forming a second passivation layer on the side of the first passivation layer facing away from the first surface in the third region, a stacked synergistic passivation can be achieved with the first passivation layer in the third region. For example, the first passivation layer focuses more on chemical passivation of saturated interface dangling bonds in the third region of the first surface, while the second passivation layer supplements the field-effect passivation, further reducing the interface state density, suppressing the edge recombination rate, reducing edge efficiency loss, and improving the conversion efficiency of the solar cell. As another example, passivation media such as alumina rely on hydrogen atom saturation of interface defects, making it easier for hydrogen at the step edges to escape outward, causing passivation degradation. The first and second passivation layers in the third region form a hydrogen barrier structure, which can lock in the hydrogen elements inside the first passivation layer, reducing the risk of rapid degradation of edge passivation performance over time and improving the reliability of the passivation structure. Furthermore, since the third region at the edge of the first surface is sunken, space can be provided to form the second passivation layer, which is beneficial for forming a thicker passivation structure in the third region, further suppressing leakage at the edge. Therefore, by controlling the distance H1 between the first region of the first surface and the second surface, the distance H2 between the second region of the first surface and the second surface, and the distance H3 between the third region of the first surface and the second surface, as well as the cooperation of the first passivation layer and the second passivation layer on the third region of the first surface, the passivation performance can be improved simultaneously, the risk of edge leakage current can be reduced, and the cutting damage can be reduced, thereby improving the performance of the solar cell.

[0025] Additional aspects and advantages of embodiments of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of this application. Attached Figure Description

[0026] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the embodiments described below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0027] Figure 1 This is a cross-sectional view of the structure of a solar cell in some embodiments of this application;

[0028] Figure 2 This is a cross-sectional view of the structure of a solar cell in some other embodiments of this application;

[0029] Figure 3 This is a cross-sectional view of the structure of a solar cell in some embodiments of this application;

[0030] Figure 4 This is a cross-sectional view of a solar cell in some embodiments of this application, showing the first and second parts of the structure.

[0031] Figure 5 This is a cross-sectional view of the structure of a solar cell in some embodiments of this application;

[0032] Figure 6 for Figure 5 A schematic diagram of part of the structure of a solar cell;

[0033] Figure 7 for Figure 1 A schematic diagram of part of the structure of a solar cell;

[0034] Figure 8 This is a cross-sectional view of the structure of a solar cell in some other embodiments of this application;

[0035] Figure 9 This is a schematic diagram of the pyramid-shaped structure in some embodiments of this application;

[0036] Figure 10 This is a cross-sectional view of the structure of a solar cell in some other embodiments of this application;

[0037] Figure 11 This is a schematic flowchart illustrating the method for manufacturing a solar cell in some embodiments of this application;

[0038] Figure 12 This is a schematic diagram of the structure of the first intermediate of the solar cell in some embodiments of this application;

[0039] Figure 13This is a schematic diagram of the structure of the first intermediate of the solar cell in some other embodiments of this application;

[0040] Figure 14 This is a schematic diagram of the structure of the second intermediate of the solar cell in some embodiments of this application;

[0041] Figure 15 This is a schematic diagram of the structure of the second intermediate of the solar cell in some other embodiments of this application;

[0042] Figure 16 This is a schematic diagram of the structure of a solar cell formed by a second intermediate of a solar cell in some embodiments of this application;

[0043] Figure 17 This is a schematic diagram of the structure of a solar cell formed by a second intermediate of a solar cell in some other embodiments of this application;

[0044] Figure 18 This is a schematic diagram of the structure of a photovoltaic module in some embodiments of this application.

[0045] Explanation of reference numerals in the attached figures:

[0046] Solar cells 100, 100a, 100b, 100c, 100d, 100e;

[0047] Bases 110, 110a, 110b, 110c, 110d; first surfaces m1, m1a, m1b, m1c; first regions z11, z11a; distance H1; second regions z21, z21a; second pyramid structure J2; target region mz; distance H2; third regions z31, z31a, z31b; first pyramid structure J1; first sub-region z311; first sub-pyramid structure J11; second sub-region z312; second sub-pyramid structure J12; distance H3; tilt angle α; distance S1; concave portion cg; second surfaces m2, m2a, m2b, m2c; first region z12; second region z22, z22a; third region z32, z32a; side surfaces m3, m3a, m3b; first part P1; first depth h1; second part P2.

[0048] Doped region 120, first doped region 120a, second doped region 120b, tunneling layer 121, doped semiconductor layer 122;

[0049] First passivation layers 130, 130a, 130b;

[0050] Second passivation layers 140, 140a, 140b;

[0051] First electrode 150;

[0052] Second electrode 160;

[0053] Pyramid-shaped structure J, height L, one-dimensional dimension W, gap X;

[0054] The first intermediate body of the solar cell is 101a and 101b, the groove is 1011a and 1011b, the depth is r1a and r1b, the width is r2a and r2b, and the cutting surface is QG1 and QG2.

[0055] The second intermediates 102a and 102b of the solar cell, and the third surfaces 3a and 3b;

[0056] Solar cells 103a and 103b, and second passivation layers 1031a and 1031b;

[0057] Photovoltaic module 10, cell string 11, encapsulation layer 12, cover plate 13, conductive strip 14;

[0058] First direction F1, second direction F2, third direction F3;

[0059] Steps S110, S120, S130, and S140. Detailed Implementation

[0060] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0061] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0062] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0063] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can be a mechanical connection or an electrical connection; they can be a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. It is worth noting that in the following description and the appended claims, "electrical connection" between one feature and another not only includes direct contact between the two features to form an electrical energy transmission or current transmission channel, but also includes an intermediate feature between the two features, which, along with the intermediate feature, forms an electrical energy transmission or current transmission channel to achieve electrical energy transmission or transmission. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0064] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0065] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0066] In the accompanying drawings, the thicknesses of layers, films, regions, substrates, etc., are exaggerated for clarity. Throughout the specification, the same reference numerals refer to the same elements. It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it may be directly on the other element or there may be intervening elements. Conversely, when an element is referred to as being "directly on" another element, there are no intervening elements.

[0067] In addition, embodiments of the application are described with reference to cross-sectional views, which are schematic diagrams of some embodiments of the application, thus allowing for the expectation of variations in the illustrated shape due to, for example, manufacturing techniques and / or tolerances. Therefore, embodiments of the application should not be limited to the specific shape of the area shown herein, but should include shape deviations due to, for example, manufacturing techniques.

[0068] Furthermore, the use of terms such as "same," "equal," or "consistent" regarding dimensions in the description of the embodiments of this application does not require absolute mathematical or geometric precision. Given the actual manufacturing, measurement, and material factors, those skilled in the art should understand that the aforementioned dimensional terms include deviations within permissible limits or unavoidable deviations. As long as such deviations do not affect the realization of the corresponding dimensions' function and technical effect in this application, they should be considered to fall within the meaning of "same dimensions" as described in the embodiments of this application.

[0069] Please refer to Figure 1 , Figure 1 This is a cross-sectional view of a solar cell 100 in some embodiments of this application. Embodiments of this application provide a solar cell 100, including a substrate 110, a doped region 120, a first passivation layer 130, and a second passivation layer 140.

[0070] The substrate 110 is used to receive incident light and generate photogenerated carriers. The substrate 110 can be selected according to actual needs. Exemplarily, the substrate 110 can be a silicon substrate, which may include one or more of monocrystalline silicon, polycrystalline silicon, amorphous silicon, or microcrystalline silicon. The doping type of the substrate 110 is not specifically limited. For example, the substrate 110 can be an N-type doped silicon substrate, or it can be a P-type doped silicon substrate; there is no specific limitation in this regard. The N-type doping element can be a group V element such as phosphorus (P), bismuth (Bi), antimony (Sb), or arsenic (As), and the P-type doping element can be a group III element such as boron (B), aluminum (Al), gallium (Ga), or indium (In). In the embodiments of this application, the substrate 110 can be an N-type monocrystalline silicon wafer, which can improve the conversion efficiency of the solar cell 100 and reduce manufacturing costs.

[0071] The substrate 110 has a first surface m1 and a second surface m2 disposed opposite to each other. Exemplarily, in conjunction with reference to... Figure 1 The first surface m1 and the second surface m2 are arranged opposite each other along the thickness direction of the substrate 110. The thickness direction of the substrate 110 is... Figure 1 The first direction F1 is shown in the diagram. For example, the first surface m1 is the backlight surface, and the second surface m2 is the light-receiving surface. Or, for another example, the first surface m1 is the light-receiving surface, and the second surface m2 is the backlight surface. It can be understood that the light-receiving surface and the backlight surface are relative terms. The light-receiving surface specifically refers to the surface on the substrate 110 of the solar cell 100 that is primarily exposed to sunlight. The light-receiving surface typically has a surface structure that can increase the light absorption area, improve the photocurrent, and help improve the efficiency of the cell.

[0072] The first surface m1 is divided into alternating first regions z11 and second regions z21. That is, along the arrangement direction of the first regions z11 and the second regions z21, an arrangement pattern of "first region z11, second region z21, first region z11, second region z21, first region z11..." or "second region z21, first region z11, second region z21, first region z11..." is formed. In other words, along the arrangement direction of the first regions z11 and the second regions z21, the region adjacent to the first region z11 is the second region z21, not another first region z11; and the region adjacent to the second region z21 is the first region z11, not another second region z21. It can be understood that along the arrangement direction of the first regions z11 and the second regions z21, the first region can be either the first region z11 or the second region z21, and the last region can be either the first region z11 or the second region z21; no specific restrictions are made here. For example, using... Figure 1 For example, the arrangement direction of the first region z11 and the second region z21 is the second direction F2, and, in Figure 1 The diagram only shows two first regions z11 and two second regions z21, and does not impose any restrictions on the number of first regions z11 and second regions z21.

[0073] The first surface m1 is further divided into a third region z31, which is located at the edge of the first surface m1 and adjacent to the second region z21. That is, in the first region z11 and the second region z21, along the arrangement direction of the first region z11 and the second region z21, at least one of the first and last regions is the second region z21. For example, with... Figure 1 For example, the case where the last region in the first region z11 and the second region z21 is the second region z21 is illustrated.

[0074] It should be noted that the aforementioned first region z11, second region z21, and third region z31 are artificially divided into regions on the first surface m1 for the purpose of describing the technical solution of the embodiments of this application. This division does not imply that the first region z11, second region z21, and third region z31 are physically separated or independent. Furthermore, there are not necessarily obvious boundaries between the aforementioned regions. For example, there are no obvious boundaries between the first region z11, second region z21, and third region z31.

[0075] For example, with Figure 1 For example, the first direction F1, the second direction F2, and the third direction F3 intersect each other. For instance, the second direction F2 and the third direction F3 can be the length direction and the width direction of the solar cell 100, respectively, and the first direction F1, the second direction F2, and the third direction F3 are perpendicular to each other, without specific restrictions.

[0076] The distance between the first region z11 and the second surface m2 is H1, the distance between the second region z21 and the second surface m2 is H2, and the distance between the third region z31 and the second surface m2 is H3, where H1 > H2 and H2 > H3.

[0077] For example, with Figure 1 For example, relative to the second region z21 and the third region z31, the first region z11 protrudes along the first direction F1; relative to the third region z31, the second region z21 protrudes along the first direction F1. Figure 1 From the illustrated perspective, the distances between the first region z11, the second region z21, and the third region z31 and the second surface m2 can be considered as the heights of the first region z11, the second region z21, and the third region z31. There is a height difference between the first region z11 and the second region z21, with the first region z11 being higher than the second region z21. Similarly, there is a height difference between the second region z21 and the third region z31, with the second region z21 being higher than the third region z31.

[0078] The distances between the first region z11, the second region z21, and the third region z31 and the second surface m2 are determined along the direction in which the first surface m1 and the second surface m2 are relatively positioned. In this embodiment, the direction in which the first surface m1 and the second surface m2 are relatively positioned is the first direction F1. When the second surface m2 has a planar or approximately planar shape, the height L of the second surface m2 is basically the same at all points. When defining the distance between each region of the first surface m1 and the second surface m2, the vertical distance from each region of the first surface m1 to the second surface m2 can be directly measured along the first direction F1, and this vertical distance can be used as the distance between each region of the first surface m1 and the second surface m2. When the second surface m2 has an undulating contour and a surface with varying heights, the same type of reference position is pre-defined on the second surface as a reference for the distance between each region of the first surface m1 and the second surface m2.

[0079] The aforementioned "planar morphology" and "approximate planar morphology" refer to the fact that the second surface m2 has no obvious undulations, warping, or depressions / protrusions. After the second surface m2 is machined, it meets the flatness tolerance requirements, the deviation of its contour from the ideal reference surface is small, and there are no obvious height differences. In other words, the second surface does not have any deliberately shaped concave or convex features, and the overall contour tends to be flat; there are only microscopic surface roughness and minor flatness deviations caused by material forming and machining. These minor deviations will not cause identifiable systematic differences in thickness at different locations, and can be equivalently regarded as planar treatment at the dimensional judgment level.

[0080] The aforementioned “undulating contour” and “surface height variation” refer to the fact that the second surface m2 has a shaped concave-convex structure, and the overall contour has obvious height variations. It is not just the microscopic surface roughness and slight flatness deviation caused by material forming and machining. This morphology will cause identifiable systematic height differences at different positions along the thickness direction of the substrate 110, which cannot be equivalently regarded as a plane at the dimensional determination level.

[0081] For example, with Figure 1 For example, to illustrate the case where the second surface m2 has an undulating profile, the distances H1 between the first region z11 and the second surface m2, H2 between the second region z21 and the second surface m2, and H3 between the third region z31 and the second surface m2 are all illustrated by selecting the same region of the second surface m2 as the reference.

[0082] For example, in actual practice, a cross-sectional sample of the solar cell 100 can be prepared, selecting a portion including the first region z11, the second region z21, the third region z31, and the second region m2 of the first surface m1, and making corresponding SEM images. For example, firstly, the solar cell 100 to be tested is cut along the first direction F1; secondly, a sample containing a first region z11, a second region z21, a third region z31, and a second surface m2 is obtained; subsequently, a microscopic image of the cross-sectional morphology of the first region z11, the second region z21, the third region z31, and the second surface m2 is obtained by scanning electron microscopy or the like; then, in the microscopic image, with the same region of the second surface m2 of the substrate 110 as the lower boundary of the measurement, and the first region z11, the second region z21, and the third region z31 of the first surface m1 as the upper boundary, the distance H1 between the first region z11 and the second surface m2, the distance H2 between the second region z21 and the second surface m2, and the distance H3 between the third region z31 and the second surface m2 are measured using image analysis software. For example, 3, 5, 6, 8, 9, 10, 15, or 20 measurement points can be selected in the first region z11 of the first surface m1. Based on the measurement data obtained from the measurement points, the average value of the measurement data is calculated, and the average value of the measurement data is used as the distance H1 between the first region z11 and the second surface m2. The distances H2 between the second region z21 and the second surface m2 and H3 between the third region z31 and the second surface m2 are also considered in the same way as the distance H1 between the first region z11 and the second surface m2, and will not be elaborated here.

[0083] In some detection methods, measuring the aforementioned distance does not require testing every area on the first surface m1; sampling is sufficient. Those skilled in the art can reasonably infer and determine the distances corresponding to other areas on the first surface m1 based on the distances corresponding to the measured samples. It is understood that the design and layout of the areas on the first surface m1 follow a regular pattern. For example, in the embodiments of this application, the distances corresponding to the first areas z11 of other first surfaces m1 can be reasonably inferred and obtained by measuring the distances corresponding to one or more first areas z11 of the first surface m1.

[0084] A doped region 120 is disposed in the first region z11. Along the thickness direction of the substrate 110, the doped region 120 is formed above or inside the first surface m1 of the substrate 110. Exemplarily, the doping type of the doped region 120 and the doping type of the substrate 110 can be the same or different. For example, the doping type of the doped region 120 and the doping type of the substrate 110 can be different, so that they can together form a PN junction structure. For example, when the substrate 110 is an N-type silicon substrate, the doped region 120 can be a P-type emitter. As another example, when the substrate 110 is a P-type silicon substrate, the doped region 120 can be an N-type emitter.

[0085] For example, the doped region 120 can be formed by diffusing a dopant element into the substrate 110 on the first surface m1 side of the substrate 110. When the substrate 110 is an N-type substrate, the P-type doped region 120 can be formed by boron diffusion into the substrate 110.

[0086] For example, the doped region 120 can also be made of doped polycrystalline silicon, microcrystalline silicon, or amorphous silicon with a doping element type opposite to that of the substrate 110. For instance, when the substrate 110 is an N-type substrate, a tunneling layer and a polycrystalline silicon, microcrystalline silicon, or amorphous silicon layer can be formed on the first surface m1 of the substrate 110 by methods such as low-pressure chemical vapor deposition (LPCVD) or plasma-enhanced chemical vapor deposition. The doped region 120 is then formed by doping the polycrystalline silicon, microcrystalline silicon, or amorphous silicon layer with a P-type doping element. In this case, the doped region 120 can be considered as a layer structure. Figure 1 For example, the doped region 120 is formed inside the substrate 110 by diffusion. In this case, the distance H1 between the first region z11 of the first surface m1 and the second surface m2 can be regarded as the distance between the upper boundary of the doped region 120 and the second surface m2.

[0087] The first passivation layer 130 is disposed on the side of the doped region 120 away from the second surface m2, on the second region z21 and on the third region z31.

[0088] The first passivation layer 130 can effectively passivate the side of the doped region 120 away from the second surface m2, the second region z21 of the first surface m1, and the third region z31 of the first surface m1, reducing the interface state density and minority carrier recombination, thereby improving the carrier transport efficiency at the interface and increasing the efficiency of the solar cell 100. The first passivation layer 130 can also reduce or eliminate reflected light on the surface of the solar cell 100 and increase light transmittance, further improving the photoelectric conversion efficiency of the solar cell 100.

[0089] For example, the first passivation layer 130 can be deposited using plasma-enhanced chemical vapor deposition (PECVD). Other methods, such as organic chemical vapor deposition, can also be used to form the first passivation layer 130. The first passivation layer 130 can be a single-layer structure, a multilayer structure, or a combination of single-layer and multilayer structures, and the thickness of each layer can be designed accordingly, without limitation. For example, the first passivation layer 130 can be any one or more combinations of silicon nitride, silicon oxynitride, silicon oxide, and aluminum oxide, without specific limitation.

[0090] The second passivation layer 140 is disposed on the side of the first passivation layer 130 located on the third region z31 that is away from the first surface m1. That is, the second passivation layer 140 is disposed at the edge region of the first passivation layer 130.

[0091] The second passivation layer 140 can further passivate the side of the first passivation layer 130 located on the third region z31 that is away from the first surface m1, reducing the interface state density and minority carrier recombination, thereby improving the carrier transport efficiency at the interface and increasing the efficiency of the solar cell 100. The second passivation layer 140 can also reduce or eliminate reflected light on the surface of the solar cell 100 and increase light transmittance, further improving the photoelectric conversion efficiency of the solar cell 100. The fabrication method and possible implementation methods of the second passivation layer 140 can be understood with reference to the first passivation layer 130, and are not specifically limited here.

[0092] On the one hand, since H1 > H2 and H2 > H3, the morphology of the first surface m1, namely the first region z11, the second region z21, and the third region z31, descends sequentially, making the morphology of the first surface m1 more gentle. This reduces the internal stress of the film layer and improves the adhesion stability of the first passivation layer 130 during its formation. Because the first region z11 of the first surface m1 is more convex, it facilitates contact between the doped region 120 and the subsequent electrode structure. Because the third region z31 at the edge of the first surface m1 is recessed, the lateral spacing between the conductive doped structures on the first surface m1 side and the second surface m2 side can be increased, enlarging the lateral leakage channel at the edge and thus helping to suppress edge leakage. Simultaneously, since the region adjacent to the third region z31 of the first surface m1 is the second region z21, and no doped region 120 is located in the second region z21, cutting to form the third region z31 and forming the solar cell 100 helps to reduce cutting damage, thereby improving the performance of the solar cell 100.

[0093] On the other hand, since the edges of the substrate 110 may be subject to cutting damage, this could lead to a large number of dangling bonds and interface defects at the edges of the substrate 110, and could also result in uneven thickness and incomplete coverage of the first passivation layer 130 at the edges. By forming a second passivation layer 140 on the side of the first passivation layer 130 located on the third region z31 away from the first surface m1, a stacked synergistic passivation can be achieved with the first passivation layer 130 located on the third region z31. For example, the first passivation layer 130 focuses more on chemical passivation of saturated interface dangling bonds in the third region z31 of the first surface m1, while the second passivation layer 140 supplements the field-effect passivation, further reducing the interface state density, suppressing the edge recombination rate, reducing edge efficiency loss, and improving the conversion efficiency of the solar cell 100. For example, passivation media such as alumina rely on hydrogen atom saturation interface defects, making it easier for hydrogen to escape from the step edges, causing passivation degradation. The first passivation layer 130 and the second passivation layer 140 on the third region z31 form a hydrogen barrier structure, which can lock the hydrogen elements inside the first passivation layer 130, reducing the risk of rapid deterioration of edge passivation performance over time and improving the reliability of the passivation structure. Furthermore, since the third region z31 at the edge of the first surface m1 is recessed, space can be provided to form the second passivation layer 140, which is conducive to forming a thicker passivation structure on the third region z31, further suppressing leakage at the edge.

[0094] Therefore, by controlling the distance H1 between the first region z11 of the first surface m1 and the second surface m2, the distance H2 between the second region z21 of the first surface m1 and the second surface m2, and the distance H3 between the third region z31 of the first surface m1 and the second surface m2, as well as the cooperation of the first passivation layer 130 and the second passivation layer 140 on the third region z31 of the first surface m1, the passivation performance can be improved simultaneously, the risk of edge leakage current can be reduced, and the cutting damage can be reduced, thereby improving the performance of the solar cell 100.

[0095] It should be noted that, compared to the method where a doped region 120 is also provided at the second region z21, in this embodiment, the doped region 120 is located at the first region z11, and the third region z31 is adjacent to the second region z21. That is, the second region z21 connects the first region z11 and the third region z31. The second region z21 forms a doping buffer barrier structure, constraining the doping boundaries between regions, thereby creating a smoother doping gradient. This allows the doped region 120 at the first region z11 to have a certain contact effect with the electrode structure, and also suppresses Auger recombination and carrier shunting losses induced by heavy doping at the second region z21, simultaneously improving the battery open-circuit voltage and fill factor. At the same time, with the cooperation of the second region z21, as mentioned above, it is also more beneficial to use the third region z31 to improve edge leakage and recombination. Furthermore, since there is no doped region 120 in the second region z21 of this embodiment, the formation of the third region z31 can not only reduce damage to the doped region 120, but also reduce the risk of stress distortion caused by high doping of the substrate 110. This results in better fracture toughness of the substrate 110 and a smoother stress distribution during the cutting process, which can suppress the initiation and propagation of microcracks and reduce the risk of edge chipping, deep microcracks, and secondary defects caused by melting and resolidification when forming the third region z31. Therefore, it is beneficial to further reduce damage during the dicing process.

[0096] Please refer to Figure 2 , Figure 2 This is a cross-sectional view of the solar cell 100a in some other embodiments of this application. According to some embodiments of this application, the second region z21 adjacent to the third region z31 can be defined as the target region mz. A second passivation layer 140a is also disposed on the side of the first passivation layer 130 located on the target region mz that faces away from the first surface m1, and the second passivation layer 140a on the target region mz and the second passivation layer 140a located on the third region z31 are connected.

[0097] The target region mz mentioned in the embodiments of this application is only an abbreviation for the second region z21 adjacent to the third region z31. It is only used for reference and distinction in the text and is not a structural restriction on the second region z21 adjacent to the third region z31.

[0098] For example, with Figure 2For example, in the first region z11 and the second region z21 of the first surface m1, along the second direction F2, both the first and last regions are the second region z21. One of these two second regions z21 is the target region mz. That is, one of these two second regions z21 is located on one side edge of the first surface m1 along the second direction F2, and the other second region z21 is adjacent to the third region z31, which is located on the other side edge of the first surface m1 along the second direction F2. In some other embodiments, both of these second regions z21 can also be the target region mz, ​​which is not specifically limited here.

[0099] Please refer to Figure 3 , Figure 3 This is a cross-sectional view of the solar cell 100b in some embodiments of this application. According to some embodiments of this application, in the first region z11 and the second region z21 of the first surface m1a of the substrate 110a, both the first and last regions are the second region z21. In this case, the first passivation layer 130a on the first surface m1a also covers two third regions z31. That is, the first surface m1a has third regions z31 on both sides of its second direction F2.

[0100] Continue with Figure 2 For example, the second passivation layer 140a is also disposed on the side of the first passivation layer 130 located on the target region mz that is away from the first surface m1. That is, the second passivation layer 140a is not only located on the third region z31, but also extends to cover the second region z21 adjacent to the third region z31. The second passivation layer 140a extending to cover the second region z21 adjacent to the third region z31 is disposed on the side of the first passivation layer 130 located on the target region mz that is away from the first surface m1.

[0101] For example, refer to Figure 2 The second passivation layer 140a located on the target region mz and the second passivation layer 140a located on the third region z31 are connected. That is, the second passivation layer 140a covering the target region mz and the second passivation layer 140a covering the third region z31 can be regarded as the same integral film layer. They are connected to each other and form a whole, rather than two independent and disconnected passivation film layers. For the sake of structural description, two corresponding regions are divided according to their location. In fact, they can be regarded as belonging to the same continuously formed second passivation layer 140a. In other embodiments, the second passivation layer 140a located on the target region mz and the second passivation layer 140a located on the third region z31 can also be formed separately, without specific limitations.

[0102] Because of the height difference between the second region z21 and the third region z31, the second passivation layer 140a is continuously arranged across the second region z21 and the third region z31. This reduces the risk of the passivation structure at the junction of the second region z21 and the third region z31 being too thin or broken, thus allowing for more complete saturation of interface defects, suppressing carrier recombination losses at the junction of the second region z21 and the third region z31, and improving the open-circuit voltage of the battery. Simultaneously, since the first passivation layer 130 and the second passivation layer 140a at the junction of the second region z21 and the third region z31 constitute a thicker passivation structure, this not only improves the reliability of film adhesion but also blocks the lateral leakage path formed along the region interface, further reducing edge leakage current. Furthermore, it reduces the risk of water vapor and impurity ion penetration at the boundary between different regions, improving the reliability of the battery. Furthermore, compared to the method where the second passivation layer 140a is only provided on the third region z31, by continuously arranging the second passivation layer 140a across the second region z21 and the third region z31, it is beneficial to expand the process window for fabricating the second passivation layer 140a and facilitate the formation of the second passivation layer 140a.

[0103] Please continue to refer to Figure 1 According to some embodiments of this application, the substrate 110 also has a side surface m3 connecting the first surface m1 and the second surface m2, and the second passivation layer 140 is also disposed on the side surface m3.

[0104] The second passivation layer 140 is also provided on the side m3, meaning that the second passivation layer 140 on the third region z31 also extends to the side m3 of the substrate 110.

[0105] The side surface m3 connecting the first surface m1 and the second surface m2 has multiple surfaces. The second passivation layer 140 can be provided on the entire surface of side surface m3, or only on a portion of side surface m3; no specific limitation is made here. For example, Figure 1 This illustration shows a case where a second passivation layer 140 is provided on the side m3 of the substrate 110 along the second direction F2. Figure 2 The illustration shows a case where a second passivation layer 140a is provided on the side m3 of the substrate 110 along the second direction F2. Figure 3 The illustration shows the case where the second passivation layer 140 is provided on the side surface m3 of both sides of the substrate 110a along the second direction F2.

[0106] For example, Figure 1 The side surface m3, where the second passivation layer 140 is located, is shown as a cut surface. Figure 2 The side surface m3, which is shown to have the second passivation layer 140a, is a cut surface. Figure 3 The schematically shown base 110a has two side surfaces m3 along the second direction F2, both of which are cut surfaces. Figure 1 and Figure 2 In the illustrated scenario, the first passivation layer 130 is also provided on the side m3 where the second passivation layer is not provided.

[0107] The cut-out side surface m3 may contain lattice damage, dangling bonds, and defect sites. The second passivation layer 140 extends from the third region z31 of the first surface m1 to the side surface m3 of the substrate 110, thereby improving the exposed substrate 110, reducing carrier recombination losses on the side surface m3, and further improving the battery's conversion efficiency. Simultaneously, since the second passivation layer 140 covers both the third region z31 and the side surface m3, there are no obvious seams at the interface between them. This not only reduces the risk of weak points due to interface gaps, improving battery reliability, but also enhances the adhesion stability of the second passivation layer 140. Furthermore, by integrally molding the second passivation layer 140 on both the third region z31 and the side surface m3, the manufacturing process is simplified, and process tolerance and yield are improved.

[0108] It should be noted that, in Figure 2 In the illustrated case, the second passivation layer 140a is disposed on the second region z21, the third region z31 and the side m3. In this case, the second passivation layer 140a can also be an integrally formed structure.

[0109] Please continue to refer to Figure 1 According to some embodiments of this application, the doping element in the doped region 120 is defined as the first doping element. The doping concentration of the first doping element in the doped region 120 is N1, the doping concentration of the first doping element in the second region z21 is N2, and the doping concentration of the first doping element in the third region z31 is N3, then N1 > N2, N2 ≥ N3.

[0110] Combined with reference Figure 4 , Figure 4 This is a cross-sectional view of a solar cell 100 in some embodiments of this application, illustrating the structure of the first portion P1 and the second portion P2. According to some embodiments of this application, the portion of the substrate 110 extending from the second region z21 towards the second surface m2 at a first depth h1 is defined as the first portion P1, and the portion of the substrate 110 opposite to the third region z31 located on the first surface m1 is defined as the second portion P2. The doping concentration of the first dopant element in the second region z21 can be considered as the doping concentration of the first dopant element in the first portion P1, and the doping concentration of the first dopant element in the third region z31 can be considered as the doping concentration of the first dopant element in the second portion P2.

[0111] The aforementioned "first part P1" and "second part P2" are both portions of the substrate 110. The division of the substrate 110 into first part P1 and second part P2 is done artificially for the purpose of describing the technical solutions of the embodiments of this application, and there is no necessarily a clear boundary between them. For example, neither first part P1 nor second part P2 has a clearly visible boundary. Figure 4 In the diagram, only the dashed line indicates the boundary between the first part P1 and the second part P2, but it is not a restriction on the first part P1 and the second part P2.

[0112] The aforementioned “first depth h1” can be determined based on the doping type of the first doped element.

[0113] For example, the first doped element is a p-type doped element, and the first depth h1 is greater than 0 μm and less than or equal to 1 μm. For example, the first depth h1 can be 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.9 μm, or 1 μm. The first depth h1 can also be any other value within the aforementioned range, without specific limitations.

[0114] For example, the first dopant element is an N-type dopant element, and the first depth h1 is greater than 0 nm and less than or equal to 100 nm. For example, the first depth h1 can be 1 nm, 10 nm, 30 nm, 50 nm, 65 nm, 80 nm, 85 nm, 90 nm, or 100 nm. The first depth h1 can also be any other value within the aforementioned range, without specific limitations.

[0115] The higher doping concentration of the first dopant element in doped region 120 allows for better contact between doped region 120 and the electrode structure, effectively reducing interface contact resistance and current transmission loss. The lower doping concentration of the first dopant element in second region z21 suppresses Auger recombination induced by high doping, reduces non-radiative losses of photogenerated carriers, and improves the battery open-circuit voltage. The lower doping concentration of the first dopant element in third region z31, meaning that the third region z31, serving as the cutting edge, also employs a low-doping setting, reduces impurity accumulation at lattice defects generated during cutting, weakens edge recombination losses, and reduces the risk of cracking and microcracks caused by residual cutting stress, thereby improving battery processing yield and edge electrical performance stability.

[0116] Thus, the synergy between the doping concentration of the first dopant element in doping region 120 and the doping concentration of the first dopant element in second region z21 not only helps to mitigate the increased recombination caused by heavy doping but also helps to alleviate the problem of high contact resistance caused by low doping. Simultaneously, it can improve the battery open-circuit voltage and fill factor. By further controlling the doping concentration of the first dopant element in third region z31 to a low level, the risk of additional recombination centers and carrier shunting losses introduced by abrupt concentration changes is reduced. Furthermore, as a cutting location, the low-doping configuration in third region z31 can suppress impurity segregation and accumulation at the cutting defect, preventing edge recombination losses from eroding inwards. Combined with the first passivation layer 130 and the second passivation layer 140 located in third region z31, edge leakage and moisture erosion can be further suppressed. Therefore, this is beneficial for further improving battery conversion efficiency and stability.

[0117] It should be noted that, for the differentiated doping layouts in the three doping regions 120, z21, and z31, to characterize the overall doping level of the first dopant element at each location, multiple measurement points can be selected within each region. The doping concentration of the first dopant element at each point is measured, and then the average doping concentration of the first dopant element in doping region 120, z21, and z31 is calculated. The average doping concentration at each location is used to characterize the overall doping level at that location, allowing for a quantitative comparison of the relative magnitudes of the three doping concentrations.

[0118] The average concentration of the first dopant element in the second region z21 is the same as the average concentration of the first dopant element in the first part P1. The average concentration of the first dopant element in the third region z31 is the same as the average concentration of the first dopant element in the second part P2. Based on the first depth h1 corresponding to the first part P1 and the dimension along the first direction F1 corresponding to the second part P2, different depths r1a or dimensions can be selected for measurement.

[0119] For example, taking the average doping concentration of the first dopant element in doping region 120 as an example, the relationship curve between the doping concentration of the first dopant element in doping region 120 and the doping depth r1a of doping region 120 can be obtained using the electrochemical capacitance-voltage (ECV) method. Taking the average doping concentration of the first dopant element in second region z21 as an example, the relationship curve between the doping concentration of the first dopant element in second region z21 and the doping depth r1a at second region z21 can be obtained using the electrochemical capacitance-voltage (ECV) method. In this way, the doping concentration within the corresponding range can be integrated to obtain the integration area. Then, by dividing the integration area by the corresponding depth r1a, the average doping concentration of the first dopant element in doping region 120 and second region z21 within the corresponding doping depth r1a range can be obtained, which are also the average doping concentration of the first dopant element in doping region 120 and the average doping concentration of the first dopant element in second region z21. The average doping concentration of the first dopant element in third region z31 can also be measured in the aforementioned manner, and will not be elaborated further.

[0120] Alternatively, an energy-dispersive X-ray spectroscopy (EDS) combined with a sample electron microscope (SEM / TEM) can be used to perform component analysis by detecting the characteristic X-rays excited when the electron beam bombards the sample, measuring the average concentration of the first dopant element at doped region 120, second region z21, or third region z31. Alternatively, atomic probe tomography (APT) can be used, where atoms at the top of the sample are evaporated one by one using lasers and high-voltage pulses, reconstructing the three-dimensional compositional distribution of the sample, and measuring the average concentration of the first dopant element at doped region 120, second region z21, and third region z31. Furthermore, secondary ion mass spectrometry (SIMS) can be used, where a primary ion beam bombards the sample, sputtering secondary ions, and then the composition of these ions is analyzed by a mass spectrometer to perform component analysis, measuring the average concentration of the first dopant element at doped region 120, second region z21, and third region z31, etc. Specific settings can be configured according to actual needs and are not limited here.

[0121] Based on some embodiments of this application, please continue to refer to Figure 1 and Figure 4 The doping type of the first doped element is the same as that of the substrate 110. N1 is 5 × 10⁻⁶. 19 cm -3 Up to 5×10 20 cm -3 .

[0122] For example, the substrate 110 is an N-type substrate, and the first doping element is an N-type doping element. Of course, the substrate 110 can also be a P-type substrate, and the first doping element can be a P-type doping element; no specific limitation is made here.

[0123] For example, N1 can be 5 × 10 19 cm -3 1×10 20 cm -3 2×10 20 cm -3 3×10 20 cm -3 4×10 20 cm -3 Or 5×10 20 cm -3 Of course, N1 can also be 5 × 10. 19 cm -3 Up to 5×10 20 cm -3 Any other value within the range.

[0124] When the doping type of the first dopant element is the same as that of the substrate 110, controlling the lower limit of the doping concentration of the first dopant element in the doped region 120 helps to form a stable ohmic contact between the electrode structure and the doped region 120, reducing interfacial contact resistance and decreasing current transmission ohmic losses. Controlling the upper limit of the doping concentration of the first dopant element in the doped region 120 helps to mitigate problems such as impurity oversaturation precipitation, lattice distortion, and Auger recombination surges caused by high doping, thus alleviating minority carrier losses. Simultaneously, it suppresses lateral over-diffusion of doped atoms during annealing, resulting in a clearer doping boundary between the doped region 120 and the second region z21, and facilitating lower doping at the second region z21, thereby suppressing Auger recombination. In this way, the conductivity and surface passivation performance of the electrode structure can be balanced, further improving the overall conversion efficiency of the battery.

[0125] Please continue to refer to Figure 1 and Figure 4 According to some embodiments of this application, the doping type of the first dopant element is the same as the doping type of the substrate 110. N2 is 1×10 16 cm -3 Up to 1×10 19 cm -3 N3 is 1×10 15 cm -3 Up to 1×10 16 cm -3 .

[0126] For example, the substrate 110 is an N-type substrate, and the first doping element is an N-type doping element. Of course, the substrate 110 can also be a P-type substrate, and the first doping element can be a P-type doping element; no specific limitation is made here.

[0127] For example, N2 can be 1×10 16 cm-3 2×10 16 cm -3 5×10 16 cm -3 1×10 17 cm -3 2×10 17 cm -3 5×10 17 cm -3 1×10 18 cm -3 2×10 18 cm -3 5×10 18 cm -3 Or 1×10 19 cm -3 Of course, N2 can also be 1×10. 16 cm -3 Up to 1×10 19 cm -3 Any other value within the range is not specifically restricted here.

[0128] For example, N3 can be 1×10 15 cm -3 2×10 15 cm -3 3×10 15 cm -3 4×10 15 cm -3 5×10 15 cm -3 6×10 15 cm -3 7×10 15 cm -3 8×10 15 cm -3 9×10 15 cm -3 Or 1×10 16 cm -3 Of course, N3 can also be 1×10. 15 cm -3 Up to 1×10 16 cm -3 Any other value within the range is not specifically restricted here.

[0129] When the doping type of the first dopant element is the same as that of the substrate 110, by controlling the upper limit of the doping concentration range of the first dopant element in the second region z21, Auger recombination, band gap shrinkage, and impurity precipitation-type lattice defects caused by high doping can be suppressed, while the lateral diffusion of impurities is constrained, which is beneficial to making the partition doping boundary clearer. By controlling the lower limit of the doping concentration range of the first dopant element in the second region z21, not only can the risk of weakening the passivation effect of the passivation layer field due to excessively low doping be reduced, but a gentler doping gradient can also be constructed between the high-doped contact region and the edge region, suppressing carrier shunting and interface-added recombination induced by abrupt concentration changes, thus balancing the passivation effect and the stability of the doped structure.

[0130] When the doping type of the first dopant element is the same as that of the substrate 110, by controlling the upper limit of the doping concentration range of the first dopant element in the third region z31, the edge is kept at a low doping level, reducing impurity segregation and aggregation at the cutting defects, reducing edge recombination loss, mitigating the risk of cracking and microcracks caused by cutting stress, and suppressing lateral leakage at the edge, reducing the risk of edge impurities interfering with the doping layout of the second region z21. By controlling the lower limit of the doping concentration range of the first dopant element in the third region z31, the risk of band distortion and passivation failure caused by excessively low edge doping can be reduced, and a smoother doping transition between the third region z31 and the second region z21 can be achieved, reducing recombination loss at the interface, thereby improving the edge electrical characteristics and long-term service reliability of the battery.

[0131] Please continue to refer to Figure 1 and Figure 4 According to some embodiments of this application, the doping type of the first dopant element is different from the doping type of the substrate 110. N1 is 5 × 10⁻⁶. 15 cm -3 Up to 5×10 16 cm -3 .

[0132] For example, the substrate 110 is an N-type substrate, and the first doping element is a P-type doping element. Of course, the substrate 110 can also be a P-type substrate, and the first doping element can be an N-type doping element; no specific limitation is made here.

[0133] For example, N1 can be 5 × 10 15 cm -3 1×10 16 cm -3 2×10 16 cm -3 3×10 16 cm -3 4×10 16 cm -3 Or 5×1016 cm -3 Of course, N1 can also be 5 × 10. 15 cm -3 Up to 5×10 16 cm -3 Any other value within the range.

[0134] When the doping type of the first dopant element differs from that of the substrate 110, controlling the lower limit of the doping concentration of the first dopant element in the doping region 120 allows for the formation of a PN junction, which is beneficial for the effective shaping of the selective contact structure. Controlling the upper limit of the doping concentration of the first dopant element in the doping region 120 helps reduce the risk of an excessively narrow depletion region and increased tunneling leakage current due to excessively high doping on both sides of the PN junction, thus reducing the risk of leakage and potential breakdown caused by localized electric field concentration. It also helps control the lateral boundary of the PN junction, facilitating the partitioning of the first region z11 and the second region z21. In this way, while meeting the conductive contact requirements of the electrode structure, it suppresses recombination losses within the PN junction, balances junction recombination and contact conductivity, and balances the electrical performance and long-term structural stability of the battery.

[0135] Please continue to refer to Figure 1 and Figure 4 According to some embodiments of this application, the doping type of the first dopant element is different from the doping type of the substrate 110. N2 is 1×10 16 cm -3 Up to 1×10 18 cm -3 .

[0136] For example, the substrate 110 is an N-type substrate, and the first doping element is a P-type doping element. Of course, the substrate 110 can also be a P-type substrate, and the first doping element can be an N-type doping element; no specific limitation is made here.

[0137] For example, N2 can be 1×10 16 cm -3 2×10 16 cm -3 5×10 16 cm -3 1×10 17 cm -3 2×10 17 cm -3 5×10 17 cm -3 Or 1×10 18 cm -3 Of course, N2 can also be 1×10. 16 cm -3 Up to 1×10 18 cm-3 Any other value within the range is not specifically restricted here.

[0138] For example, the third region z31 has no first doped element or contains trace amounts of the first doped element. The third region z31 has no first doped element, meaning N3 is 0 cm⁻¹. -3 The third region z31 contains a trace amount of the first dopant element, meaning that effective P-type doping cannot be formed in the third region z31.

[0139] When the doping type of the first dopant element differs from that of the substrate 110, controlling the upper limit of the doping concentration of the first dopant element in the second region z21 can reduce the risk of excessive doping concentration causing PN junction tunneling leakage, increased Auger recombination, and lateral over-diffusion of impurities, thereby reducing the generation of lattice defects. Controlling the lower limit of the doping concentration of the first dopant element in the second region z21 can reduce the risk of local band distortion caused by excessively low doping levels, thus improving the passivation effect of the passivation field. Simultaneously, it can create a gentler doping gradient between the doped region 120 and the third region z31, thereby suppressing interfacial carrier shunting and additional recombination losses.

[0140] When the doping type of the first dopant element and the doping type of the substrate 110 are different, the doping concentration of the first dopant element in the third region z31 is controlled to 0 cm⁻¹. -3 This not only reduces the risk of edge leakage and edge recombination loss, but also reduces the doping effect on the second region z21, while improving the edge cutting stress state and reducing the rate of cracking and microcracks. Therefore, it can improve the battery's electrical performance and process reliability.

[0141] Please refer to Figure 5 , Figure 5 This is a cross-sectional view of the solar cell 100c in some embodiments of this application. According to some embodiments of this application, the third region z31a of the first surface m1b of the substrate 110b includes a first side connecting to the corresponding second region z21, and a second side opposite to the first side and away from the second region z21. The third region z31a is inclined relative to the corresponding second region z21 from the first side to the second side.

[0142] The second region z21 protrudes relative to the third region z31a, and the third region z31a is tilted, that is, the surface of the third region z31a is tilted relative to the first surface of the base 110b to form a slope structure, which extends obliquely from the position near the second region z21 to the outer edge of the base 110b.

[0143] For example, in Figure 5In the illustrated scenario, the first passivation layer 130b is not provided on the side m3b of the substrate 110b.

[0144] Thus, on the one hand, during the dicing process, less material is removed from the substrate 110b, reducing edge loss and improving material utilization. Simultaneously, the inclined third region z31a releases residual stress more smoothly, resulting in smoother fragment separation and reducing the likelihood of fragment adhesion. Furthermore, this structure inhibits the inward propagation of microcracks, reducing edge cracks and defective fragments, and improving dicing yield. On the other hand, the inclined slope not only improves the morphology of the second passivation layer 140b after deposition, allowing for a more uniform and continuous film thickness along the third region z31a, but also disperses stress concentration, reducing the risk of edge cracking and peeling of the passivation film.

[0145] Furthermore, when the second passivation layer 140b is also provided on the side m3b, the tilted third region z31a also facilitates the formation of the second passivation layer 140b. Moreover, during the encapsulation process of the solar cell 100c, the tilted edge also facilitates the venting and bonding of the encapsulating adhesive, reducing edge bubbles and delamination defects, and improving the reliability of the encapsulation interface adhesion.

[0146] Please continue to refer to Figure 5 and in conjunction with reference Figure 6 , Figure 6 for Figure 5 A schematic diagram of a portion of the structure of the solar cell 100c is shown. According to some embodiments of this application, the tilt angle α of the third region z31a is 30° to 70°.

[0147] The tilt angle α of the third region z31a can be understood as the angle formed by the line connecting the first side and the second side of the third region z31a and the second direction F2.

[0148] For example, the tilt angle α of the third region z31a can be 30°, 40°, 50°, 55°, 60° or 70°. Of course, the tilt angle α of the third region z31a can also be any other value in the range of 30° to 70°, and no specific limitation is made here.

[0149] By controlling the range of the tilt angle α of the third region z31a, not only can the third region z31a have a certain slope, which can reduce the cutting kerf width r2a and reduce the loss of edge silicon material, but also release the residual stress of cutting more smoothly, making the separation of the cleavage smoother and reducing defects such as bridging, hidden cracks and edge breakage. It can also reduce the risk of uneven distribution of passivation structure thickness and stress concentration cracking of film layer caused by the third region z31a being too steep.

[0150] Please continue to refer to Figure 5 and Figure 6 According to some embodiments of this application, along the second direction F2, the distance S1 between the first side of the third region z31a and the second side of the third region z31a is 2.5 μm to 5 μm.

[0151] For example, the distance S1 can be 2.5μm, 3μm, 3.5μm, 3.8μm, 4μm, 4.5μm, or 5μm. Of course, the distance S1 can also be any other value in the range of 2.5μm to 5μm.

[0152] By controlling the range of distance S1 corresponding to the third region z31a, on the one hand, more space can be reserved for the slicing process, reducing cutting damage, and residual cutting stress can be released more fully, reducing the risk of edge chipping, microcracks, and off-cutting. Simultaneously, it also provides space for the second passivation layer 140b, which is beneficial for improving the passivation effect. On the other hand, it can not only reduce the material and process losses caused by etching, doping, and coating at the edges, controlling production costs, but also reduce the risk of lateral carrier shunting and additional interface recombination caused by an excessively long doping gradient transition region. Therefore, by controlling the distance S1 corresponding to the third region z31a, processing yield, edge passivation protection effect, battery photoelectric performance, and production cost can be balanced.

[0153] Please continue to refer to Figure 1 and in conjunction with reference Figure 7 , Figure 7 for Figure 1 A schematic diagram of a portion of the structure of the solar cell 100 is shown. According to some embodiments of this application, the third region z31 includes a first sub-region z311 and a second sub-region z312 connected together. The side of the first sub-region z311 away from the second sub-region z312 is connected to the corresponding second region z21. The first sub-region z311 and the second sub-region z312 define a recess cg.

[0154] In some embodiments, the first sub-region z311 and the second sub-region z312 can be smoothly connected, and the third region z31 is generally arc-shaped. In other embodiments, the first sub-region z311 extends generally along a first direction F1, and the second sub-region z312 extends generally along a second direction F2; the first sub-region z311 and the second sub-region z312 can be arranged generally perpendicularly. No specific limitations are imposed here. Figure 7 For example, the first sub-region z311 and the second sub-region z312 are set roughly perpendicularly.

[0155] By setting the first sub-region z311 and the second sub-region z312, the edge morphology transition stress can be dispersed, alleviating the problem of stress concentration in the passivation film, reducing the risk of corner cracking, lifting, or detachment of the second passivation layer 140, and improving the adhesion stability of the film layer. Simultaneously, the concave cg-shaped bending morphology not only extends the inward penetration path of water vapor and impurity ions, enhancing barrier protection, but also lengthens the lateral leakage path at the edge, synergistically reducing edge leakage current and improving the parallel resistance and fill factor of the cell. Compared to the tilted setting of the third region z31, defining the third region z31 with the concave cg also helps to increase light utilization, thereby increasing short-circuit current and improving the performance of the solar cell 100.

[0156] Furthermore, during the cutting process, not only can the cutting path be set within the recessed cg region to reduce silicon material loss and improve material utilization, but the first sub-region z311 and the second sub-region z312 can also be used to release residual stress from the cutting process in stages, inhibiting the inward propagation of microcracks and thus reducing the risk of edge chipping and hidden cracks. Moreover, the recessed cg region can also serve as a positioning marker, improving the tolerance for errors in cutting alignment.

[0157] Please refer to Figure 8 , Figure 8 This is a cross-sectional view of the solar cell 100d in some other embodiments of this application. According to some embodiments of this application, a first pyramidal structure J1 is provided on the third region z31b of the first surface m1c of the substrate 110c, and a second pyramidal structure J2 is provided on the second region z21a. Figure 8 In the middle, the second region z21a is the target region mza.

[0158] The first pyramid-shaped structure J1 and the second pyramid-shaped structure J2 can be set to have different sizes and shapes, or they can use the same size and shape. No specific restrictions are imposed here.

[0159] In this way, on the one hand, the incident light can be refracted and reflected multiple times, extending the optical absorption path, reducing surface reflection loss, increasing the generation of photogenerated carriers, increasing the short-circuit current of the battery, and at the same time, breaking up the local light concentration phenomenon at the edge, reducing the risk of Auger recombination loss caused by excessive carrier concentration in the third region z31b. On the other hand, the undulating morphology of the pyramid-shaped structure can not only increase the actual interface area between the substrate 110c and the passivation structure, but also fully saturate the surface dangling bonds, reduce the interface state density, and improve the passivation performance, but also help improve the reliability of film adhesion.

[0160] Combined with reference Figure 9 , Figure 9This is a schematic diagram of the pyramid-shaped structure J in some embodiments of this application. In the embodiments of this application, the height L of the pyramid-shaped structure J refers to the vertical distance from the base surface where the bottom of the pyramid-shaped structure J is located upwards to the top of the pyramid. The one-dimensional dimension W of the pyramid-shaped structure J refers to the length, width, diagonal length, etc. of the base, and is not specifically limited here. Figure 9 The one-dimensional dimension W shown in the figure is the side length of one side of the base of the pyramid-shaped structure J. The gap X between the two pyramid-shaped structures J is the distance between the bottom edges of the two pyramid-shaped structures J.

[0161] In some methods, the height L, one-dimensional dimension W, and corresponding gap X of the pyramid-shaped structure J can be measured using a testing instrument. The testing instrument can be an optical microscope (OM), an atomic force microscope (AFM), a scanning electron microscope (SEM), a transmission electron microscope (TEM), etc., without specific limitations.

[0162] For example, in practice, a cross-sectional sample of the solar cell can be prepared, selecting the portion containing the pyramidal structure and creating a corresponding SEM image. For instance, firstly, the solar cell under test is cut along the first direction F1; secondly, a sample containing the pyramidal structure is obtained; subsequently, a microscopic image of the cross-sectional morphology with the pyramidal structure is obtained using a scanning electron microscope or similar tool; then, in this microscopic image, the height of the pyramidal structure is measured using image analysis software, with the base of the pyramidal structure as the lower boundary and the top of the pyramidal structure as the upper boundary; the gap between two adjacent pyramidal structures is measured using image analysis software, with the edge of the base of the pyramidal structure as the boundary; and the one-dimensional dimension of the pyramidal structure is measured using image analysis software, with the lateral boundary of the base of the pyramidal structure as the boundary. Alternatively, the film layer on the solar cell under test can be removed first, and then a sample containing the pyramidal structure can be obtained. Subsequently, a microscopic image of the morphology of the sample with the pyramidal structure from a top-down view along the first direction F1 can be obtained using a scanning electron microscope or similar tool. Then, the length, width, and diagonal length of the base of the pyramidal structure are measured using image analysis software, thereby obtaining the one-dimensional dimension of the pyramidal structure.

[0163] It is understandable that the morphology, parameters, and measurement methods of other types of pyramid-shaped structures illustrated below can be understood and implemented by referring to the methods illustrated above, without further elaboration.

[0164] Please continue to refer to Figure 8 According to some embodiments of this application, the height of the first pyramidal structure J1 is less than or equal to the height of the second pyramidal structure J2. According to other embodiments of this application, the one-dimensional dimension of the first pyramidal structure J1 is less than or equal to the one-dimensional dimension of the second pyramidal structure J2. According to still other embodiments of this application, the gap between two adjacent first pyramidal structures J1 is less than or equal to the one-dimensional dimension of two adjacent second pyramidal structures J2.

[0165] That is, the first pyramidal structure J1 and the second pyramidal structure J2 must satisfy at least one of the following: 1. The height of the first pyramidal structure J1 is less than or equal to the height of the second pyramidal structure J2; 2. The one-dimensional dimension of the first pyramidal structure J1 is less than or equal to the one-dimensional dimension of the second pyramidal structure J2; 3. The gap between two adjacent first pyramidal structures J1 is less than or equal to the one-dimensional dimension of two adjacent second pyramidal structures J2.

[0166] By setting the height of the first pyramidal structure J1 to be less than or equal to the height of the second pyramidal structure J2, the taller second pyramidal structure J2 on the second region z21 can extend the optical path and increase the light absorption and passivation area. The shorter first pyramidal structure J1 on the third region z31 can not only reduce edge morphology undulation and reflectivity, but also reduce the risk of stress cracking of the passivation film, and help reduce cutting damage to adapt to edge cutting processes, thereby reducing the risk of hidden cracks and edge breakage.

[0167] By setting the one-dimensional dimension of the first pyramid-shaped structure J1 to be less than or equal to the one-dimensional dimension of the second pyramid-shaped structure J2, the larger one-dimensional dimension of the second pyramid-shaped structure J2 is beneficial to improve light absorption capacity and texturing stability. The smaller one-dimensional dimension of the first pyramid-shaped structure J1 allows for more structures to be arranged at the edge, which improves passivation performance while reducing morphological changes caused by the smaller distance between the third region z31 and the second surface m2, thus facilitating the formation of the passivation structure.

[0168] By setting the gap between two adjacent first pyramid-shaped structures J1 to be less than or equal to the one-dimensional dimension of two adjacent second pyramid-shaped structures J2, the second pyramid-shaped structure J2 with a larger gap X is beneficial to control corrosion loss and texturing cost, while the second pyramid-shaped structure J2 with a smaller gap X is beneficial to make the first pyramid-shaped structures J1 at the edge more densely arranged, further increasing the passivation area, lengthening the leakage and water vapor penetration path, further improving the performance at the edge and reducing the risk of edge leakage.

[0169] Furthermore, when the height of the first pyramidal structure J1 is less than or equal to the height of the second pyramidal structure J2, the one-dimensional dimension of the first pyramidal structure J1 is less than or equal to the one-dimensional dimension of the second pyramidal structure J2, and the gap between two adjacent first pyramidal structures J1 is less than or equal to the one-dimensional dimension of two adjacent second pyramidal structures J2, in addition to taking into account the advantages mentioned above, it can also further take into account the photoelectric performance of the battery, the long-term reliability of the edge, and the process compatibility.

[0170] Please continue to refer to Figure 8 According to some embodiments of this application, the height of the first pyramidal structure J1 is 0.5 μm to 1.5 μm, and the height of the second pyramidal structure J2 is 1.5 μm to 2.5 μm. According to other embodiments of this application, the one-dimensional dimension of the first pyramidal structure J1 is 2 μm to 5 μm, and the one-dimensional dimension of the second pyramidal structure J2 is 4 μm to 6 μm. According to still other embodiments of this application, the gap between two adjacent first pyramidal structures J1 is 1 μm to 3 μm, and the one-dimensional dimension of two adjacent second pyramidal structures J2 is 2 μm to 4 μm.

[0171] That is, the first pyramidal structure J1 and the second pyramidal structure J2 satisfy at least one of the following: 1. The height of the first pyramidal structure J1 is 0.5μm to 1.5μm and the height of the second pyramidal structure J2 is 1.5μm to 2.5μm; 2. The one-dimensional dimension of the first pyramidal structure J1 is 2μm to 5μm and the one-dimensional dimension of the second pyramidal structure J2 is 4μm to 6μm; 3. The gap between two adjacent first pyramidal structures J1 is 1μm to 3μm and the one-dimensional dimension of two adjacent second pyramidal structures J2 is 2μm to 4μm.

[0172] By controlling the lower limit of the height range of the first pyramidal structure J1, a more effective structure can be formed, improving edge anti-reflection and passivation performance. By controlling the upper limit of the height range of the first pyramidal structure J1, the risk of stress cracking of the passivation film caused by excessive undulation of the pyramidal structure J1 can be reduced, and damage during the cutting process can also be reduced.

[0173] By controlling the lower limit of the one-dimensional size range of the first pyramid-shaped structure J1, it is beneficial to make the pyramid-shaped morphology more complete. By controlling the upper limit of the one-dimensional size range of the first pyramid-shaped structure J1, it is possible to arrange the edges with higher density, thereby increasing the total passivation area and thus improving the edge passivation effect.

[0174] By controlling the lower limit of the gap between two adjacent first pyramidal structures J1, the risk of bottom connection between adjacent pyramidal structures can be reduced, which is beneficial to the formation of passivation structures. By controlling the upper limit of the gap between two adjacent first pyramidal structures J1, it is not only beneficial to maintain a higher density of edge arrangement characteristics and increase the total passivation area, but also to lengthen the edge leakage path and dielectric penetration path, suppress edge leakage and attenuation, and reduce the risk of poor microcrack bridging.

[0175] By controlling the lower limit of the height range of the second pyramidal structure J2, it is beneficial to extend the optical path, improve light absorption efficiency, increase specific surface area, and reduce surface recombination. By controlling the upper limit of the height range of the second pyramidal structure J2, not only can the risk of cracking and peeling caused by excessive thermal stress of the passivation film be reduced, but the texturing cost can also be controlled.

[0176] By controlling the lower limit of the one-dimensional size range of the second pyramidal structure J2, it is beneficial to make the second pyramidal structure J2 more regular, thereby improving the uniformity of photoelectric performance. By controlling the upper limit of the one-dimensional size range of the second pyramidal structure J2, the risks of insufficient passivation area per unit area and uneven doping diffusion are reduced.

[0177] By controlling the lower limit of the one-dimensional dimension of two adjacent second pyramidal structures J2, the risk of bottom connection between adjacent pyramidal structures can be reduced. By controlling the upper limit of the one-dimensional dimension of two adjacent second pyramidal structures J2, it is beneficial to reduce the risk of insufficient anti-reflection and passivation performance due to excessively sparse arrangement, while also balancing optoelectronic gain and production cost.

[0178] Furthermore, by simultaneously controlling the first pyramidal structure J1 and the second pyramidal structure J2, the second pyramidal structure J2 can focus on improving the overall light absorption and basic passivation level, while the first pyramidal structure J1 can take into account reducing the risk of edge leakage and cooperate with the cutting process. Thus, the overall photoelectric conversion efficiency of the battery, the reliability of the edges, and the manufacturing cost can be balanced.

[0179] Please continue to refer to Figure 8 According to some embodiments of this application, the third region z31b includes a first sub-region z311 and a second sub-region z312. The first sub-region z311 connects the second region z21 and the second sub-region z312, and the first sub-region z311 and the second sub-region z312 define a recess cg. The first pyramid-shaped structure J1 includes a first sub-pyramid-shaped structure J11 disposed on the first sub-region z311 and a second sub-pyramid-shaped structure J12 disposed on the second sub-region z312.

[0180] The first sub-pyramid structure J11 and the second sub-pyramid structure J12 can be set to have different sizes and shapes, or they can use the same size and shape. No specific restrictions are imposed here.

[0181] In this way, on the one hand, it not only helps to improve the edge passivation performance and stability, but also allows for differentiated design of the morphological parameters of the two types of sub-pyramids based on the different defect densities of the first sub-region z311 and the second sub-region z312 used for outer cutting. This reduces edge recombination loss while improving passivation performance, and also takes into account manufacturing costs. On the other hand, by using the concave cg in conjunction with the first sub-pyramid structure J11 and the second sub-pyramid structure J12, the light absorption path can be extended, further reducing the surface reflectivity at the edge, while also reducing the risk of edge leakage.

[0182] Of course, in some other embodiments, the first sub-region z311 may have a pyramid-shaped structure J, while the second sub-region z312 may not have a pyramid-shaped structure J; or the first sub-region z311 may not have a pyramid-shaped structure J, while the second sub-region z312 may have a pyramid-shaped structure J. No specific limitation is made here.

[0183] Please continue to refer to Figure 8 According to some embodiments of this application, the height of the first sub-pyramid structure J11 is greater than or equal to the height of the second sub-pyramid structure J12. According to some embodiments of this application, the one-dimensional dimension of the first sub-pyramid structure J11 is greater than or equal to the one-dimensional dimension of the second sub-pyramid structure J12. According to other embodiments of this application, the gap between two adjacent first sub-pyramid structures J11 is greater than or equal to the gap between two adjacent second sub-pyramid structures J12.

[0184] That is, the first sub-pyramid structure J11 and the second sub-pyramid structure J12 must satisfy at least one of the following: 1. The height of the first sub-pyramid structure J11 is greater than or equal to the height of the second sub-pyramid structure J12; 2. The one-dimensional dimension of the first sub-pyramid structure J11 is greater than or equal to the one-dimensional dimension of the second sub-pyramid structure J12; 3. The gap between two adjacent first sub-pyramid structures J11 is greater than or equal to the gap between two adjacent second sub-pyramid structures J12.

[0185] By controlling the height of the first sub-pyramid structure J11 to be greater than or equal to the height of the second sub-pyramid structure J12, the taller first sub-pyramid can increase the light absorption and passivation area inside the concave cg, and smooth the morphological transition. The shorter second sub-pyramid can reduce the edge undulation amplitude, which is beneficial to reduce cutting damage and improve the quality of the passivation structure.

[0186] By controlling the one-dimensional size of the first sub-pyramid structure J11 to be greater than or equal to the one-dimensional size of the second sub-pyramid structure J12, the larger size of the first sub-pyramid can improve the light absorption performance and doping uniformity on the inner side, while the smaller size of the second sub-pyramid can arrange more structures on the edge, increasing the total passivation area, which is beneficial for passivating cutting defects and further reducing cutting damage.

[0187] By controlling the gap between two adjacent first sub-pyramid structures J11 to be greater than or equal to the gap between two adjacent second sub-pyramid structures J12, a larger gap allows for a relatively sparse arrangement of the inner first sub-pyramid structures J11, which can reduce structural interconnection while controlling the loss of the substrate 110 material. A smaller gap allows for a greater arrangement of the outer second sub-pyramid structures J12, thereby further improving passivation capability, improving edge leakage current, and reducing cutting damage.

[0188] Furthermore, by simultaneously controlling the first sub-pyramid structure J11 and the second sub-pyramid structure J12, the overall morphology transitions more smoothly and continuously from the second region z21 to the inside and outside of the concave portion cg, improving the uniformity of the passivation structure and further enhancing the reliability of the edge passivation structure. Moreover, the cooperation between the first sub-pyramid structure J11 and the second sub-pyramid structure J12 allows for corresponding degrees of passivation to be achieved for different defect densities inside and outside the concave portion cg, thus balancing photoelectric requirements, passivation performance, reduction of cutting damage, and edge recombination.

[0189] Please continue to refer to Figure 8 According to some embodiments of this application, the height of the first sub-pyramid structure J11 is 0.8 μm to 1.5 μm, and the height of the second sub-pyramid structure J12 is 0.5 μm to 1 μm. According to other embodiments of this application, the one-dimensional dimension of the first sub-pyramid structure J11 is 3 μm to 5 μm, and the one-dimensional dimension of the second sub-pyramid structure J12 is 2 μm to 4 μm. According to still other embodiments of this application, the gap between two adjacent first sub-pyramid structures J11 is 1.5 μm to 3 μm, and the gap between two adjacent second sub-pyramid structures J12 is 1 μm to 2 μm.

[0190] That is, the first sub-pyramid structure J11 and the second sub-pyramid structure J12 must satisfy at least one of the following: 1. The height of the first sub-pyramid structure J11 is 0.8μm to 1.5μm, and the height of the second sub-pyramid structure J12 is 0.5μm to 1μm; 2. The one-dimensional dimension of the first sub-pyramid structure J11 is 3μm to 5μm, and the one-dimensional dimension of the second sub-pyramid structure J12 is 2μm to 4μm; 3. The gap between two adjacent first sub-pyramid structures J11 is 1.5μm to 3μm, and the gap between two adjacent second sub-pyramid structures J12 is 1μm to 2μm.

[0191] By controlling the lower limit of the height of the first sub-pyramid structure J11, a smoother overall morphology can be achieved while balancing anti-reflection and passivation. By controlling the upper limit of the height of the first sub-pyramid structure J11, manufacturing costs can be controlled while reducing stress cracking in the passivation structure.

[0192] By controlling the lower limit of the one-dimensional dimension of the first sub-pyramid structure J11, it is beneficial to make the pyramid shape more complete and regular, thereby improving the uniformity of the surface photoelectric properties. By controlling the upper limit of the one-dimensional dimension of the first sub-pyramid structure J11, while taking into account the total passivation area to improve passivation performance, the outward morphology trend can be made more gradual.

[0193] By controlling the lower limit of the gap between two adjacent first sub-pyramid-shaped structures J11, the risk of adjacent pyramids connecting at their bases can be reduced. By controlling the upper limit of the gap between two adjacent first sub-pyramid-shaped structures J11, the risk of weakening the anti-reflection and passivation effect due to overly sparse arrangement can be reduced, and manufacturing costs can also be controlled more reasonably.

[0194] By controlling the lower limit of the height of the second sub-pyramid structure J12, both edge reflection reduction and passivation can be achieved. By controlling the upper limit of the height of the second sub-pyramid structure J12, the undulation of the edge surface can be reduced, which helps to reduce cutting damage and thus improve cutting quality and passivation effect.

[0195] By controlling the lower limit of the one-dimensional dimension of the second sub-pyramid structure J12, it is beneficial to make the structure on the outer side of the certificate more regular. By controlling the upper limit of the one-dimensional dimension of the second sub-pyramid structure J12, it is beneficial to increase the total passivation area, passivate the high-density defects caused by the cutting, and thus improve the performance at the edge.

[0196] By controlling the lower limit of the gap between two adjacent second sub-pyramid structures J12, the risk of the bottoms of the two adjacent second sub-pyramid structures J12 connecting can be reduced. By controlling the upper limit of the gap between two adjacent second sub-pyramid structures J12, it is beneficial to maintain the advantage of close-packed arrangement, thereby enhancing edge passivation and reducing cutting damage, and improving the yield of diced wafers.

[0197] Furthermore, by simultaneously controlling the first sub-pyramid structure J11 and the second sub-pyramid structure J12, the photoelectric performance requirements can be met while suppressing the composite loss at the cutting edge, and the reliability of the structure at the edge can be improved while reducing the manufacturing cost.

[0198] Please continue to refer to Figure 1 According to some embodiments of this application, the thickness of the first passivation layer 130 is 20 nm to 50 nm.

[0199] For example, the thickness of the first passivation layer 130 can be 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, or 50nm. The thickness of the first passivation layer 130 can also be any other value in the range of 20nm to 50nm, without any specific limitation.

[0200] By adopting the structure of the first region z11, the second region z21, the third region z31, the first passivation layer 130 and the second passivation layer 140 in the embodiment of this application, cutting damage can be improved, which in turn makes it easier to set the thickness of the first passivation layer 130 to be smaller and reduce manufacturing costs.

[0201] In some other embodiments, the thickness of the first passivation layer 130 may also be other values ​​such as 55nm, 60nm, 65nm or 70nm, and no specific limitation is made here.

[0202] Please continue to refer to Figure 1 According to some embodiments of this application, the second surface m2 is divided into alternating first regions z12 and second regions z22. The second surface m2 is also divided into a third region z32, which is located at the edge of the second surface m2 and adjacent to the second region z22. The distance between the first region z12 and the first surface m1 is greater than the distance between the second region z22 and the first surface m1, and the distance between the second region z22 and the first surface m1 is greater than the distance between the third region z32 and the first surface m1. A doped region 120 is disposed in the first region z12. A first passivation layer 130 is also disposed on the side of the doped region 120 away from the first surface m1, on the second region z22, and on the third region z32. A second passivation layer 140 is also disposed on the side of the first passivation layer 130 located on the third region z32 away from the second surface m2.

[0203] Let the doped region 120 in the first region z11 of the first surface m1 be defined as the first doped region 120a, and let the doped region 120 in the first region z12 of the second surface m2 be defined as the second doped region 120b. The doping type of the first doped region 120a and the doping type of the second doped region 120b are different. The doping element of the first doped region 120a is the first doping element, and the doping element of the second doped region 120b is the second doping element. For example, the first doping element is an N-type doping element, and the second doping element is a P-type doping element. Or, for example, the first doping element is a P-type doping element, and the second doping element is an N-type doping element. No specific restrictions are imposed here.

[0204] The implementation methods and advantages of the first region z12, the second region z22, the third region z32, the second doped region 120b, the first passivation layer 130, and the second passivation layer 140 on the second surface m2 side can be understood with reference to the first surface m1 side, and will not be repeated here. It is understood that if the second surface m2 side also adopts the same implementation method as the first surface m1 side, the passivation performance can be further improved, the risk of edge leakage current can be further reduced, and the cutting damage can be further reduced, thereby contributing to further improvement of the performance of the solar cell 100. Furthermore, the doped region 120 illustrated in some of the aforementioned embodiments is relative to the first surface m1 side; that is, the doped region 120 illustrated in some of the aforementioned embodiments can be considered as the first doped region 120a.

[0205] It should be noted that the first region z11 of the first surface m1 does not necessarily correspond to the first region z12 of the second surface m2 along the first direction F1, the second region z21 of the first surface m1 does not necessarily correspond to the second region z22 of the second surface m2 along the first direction F1, and the third region z31 of the first surface m1 does not necessarily correspond to the third region z32 of the second surface m2 along the first direction F1. For example, in Figure 1 The diagram illustrates the situation where the first region z11 of the first surface m1 corresponds to the first region z12 of the second surface m2 along the first direction F1, the second region z21 of the first surface m1 corresponds to the second region z22 of the second surface m2 along the first direction F1, and the third region z31 of the first surface m1 corresponds to the third region z32 of the second surface m2 along the first direction F1.

[0206] Please continue to refer to Figure 2 According to some embodiments of this application, the second passivation layer 140a is further disposed on the side of the first passivation layer 130 located on the corresponding second region z22 opposite to the first surface m1, and the second passivation layer 140a located on the corresponding second region z22 and the second passivation layer 140a located on the third region z32 are connected. The corresponding second region z22 is the region adjacent to the third region z32. The relevant implementation methods and advantages can be understood with reference to the case on the first surface m1 side, and will not be elaborated here. Of course, in Figure 5 In the illustrated scenario, the second passivation layer 140b also extends to the second region z21 and the second region z22.

[0207] Please continue to refer to Figure 3 According to some embodiments of this application, in the first region z12 and the second region z22 of the second surface m2a of the substrate 110a, both the first region and the last region are the second region z22. At this time, the first passivation layer 130a on the second surface m2a also covers two third regions z32. That is, the second surface m2a has third regions z32 on both sides along the second direction F2. Of course, in Figure 5 The illustrated scenario also shows that the first surface m1b has a third region z31a on both sides of the second direction F2, and the second surface m2b has a third region z32b on both sides of the second direction F2.

[0208] Please continue to refer to Figure 5 According to some embodiments of this application, the third region z32a of the second surface m2b includes a first side connected to the corresponding second region z22, and a second side opposite to the first side and away from the second region z22. The third region z32a is inclined relative to the corresponding second region z22 from the first side to the second side. The related implementation methods and advantages can be understood with reference to the case of the first surface m1b, and will not be repeated here.

[0209] Please refer to Figure 10 , Figure 10 This is a cross-sectional view of the solar cell 100e in some other embodiments of this application. According to some embodiments of this application, a first pyramidal structure J1 is provided on the third region z31b of the first surface m1c of the substrate 110d, and a second pyramidal structure J2 is provided on the second region z21a. Pyramidal structures (not shown in the figure) are also provided on the second region z22a and the third region z32a of the second surface m2d of the substrate 110d. Related implementation methods and advantages can be understood by referring to the situation on the first surface side in other embodiments, and will not be elaborated here.

[0210] It should be noted that the pyramid-shaped structure can be configured even more flexibly. For example, using... Figures 1 to 5 For example, the pyramid-shaped structure can be omitted for the first region z11, the second region z21, the third region z31, the first region z12, the second region z22, and the third region z32. Figure 8 For example, pyramid-shaped structures can be set on the first region z11a, the second region z21a, and the third region z31b of the first surface m1c of the base 110c, while pyramid-shaped structures can be omitted on the first region z12, the second region z22, and the third region z32 of the second surface m2. Figure 10 For example, pyramid-shaped structures can be set on the first region z11a, the second region z21a, the third region z31b of the first surface m1c of the base 110d, and the second region z22a of the second surface m2c, but no pyramid-shaped structure is set on the first region z12 of the second surface m2c. No specific restrictions are imposed here.

[0211] In other embodiments, the tower base structure can be configured more flexibly. For example, the tower base structure may be provided on at least one of the three regions: the first region z12 of the second surface m2 of the base 110, the second region z22 of the second surface m2, and the third region z32 of the second surface m2. As another example, the tower base structure may be provided on at least one of the three regions: the first region z12 of the second surface m2 of the base 110, the second region z22 of the second surface m2, and the third region z32 of the second surface m2. No specific limitations are imposed here.

[0212] In some embodiments, the base structure and pyramid-shaped structure can be arranged more flexibly. For example, a pyramid-shaped structure can be arranged on the first surface m1 of the base 110 and the third region z32 of the second surface m2, while a base structure can be arranged on both the first region z12 and the second region z22 of the second surface m2 of the base 110. Another example is that a pyramid-shaped structure can be arranged on the first surface m1 of the base 110, and a base structure can be arranged on the second surface m2 of the base 110. No specific limitations are imposed here.

[0213] It should also be noted that the surface undulation of the area where the base structure is located can be less than that of the area where the pyramid-shaped structure is located. Furthermore, the base structure can be a partial or complete base structure, etc., without limitation. Alternatively, the base structure can be a polished structure, for example, a recessed structure. Exemplarily, the base structure is a structure with a recessed structure. For example, the base structure can be a recessed structure with a square, near-square, or rectangular shape. In addition, the pyramid-shaped structure and the base structure can also be formed using laser or chemical etching methods.

[0214] In the embodiments illustrated in the above figures, the implementation of the second surface m2 side of the substrate 110 is the same as that of the first surface m1 side. In some other embodiments, the implementation of the second surface m2 side of the substrate 110 may differ from that of the first surface m1 side. For example, the second surface m2 of the substrate 110 may not be divided into a third region z32. Another example is that the second surface m2 of the substrate 110 is divided into a third region z32, and the third region z32 of the second surface m2 and the third region z31 of the first surface m1 are offset along the first direction F1. No specific limitations are imposed here.

[0215] Based on some embodiments of this application, please continue to refer to Figure 1The second doped region 120b includes a tunneling layer 121 disposed on the first region z12 of the second surface m2 and a doped semiconductor layer 122 disposed on the side of the tunneling layer 121 opposite to the substrate 110.

[0216] The tunneling layer 121 serves to passivate the interface of the first region z12 on the second surface m2 of the substrate 110, reduce the interface state density, and decrease carrier recombination, thus achieving a chemical passivation effect. Specifically, by saturating the dangling bonds in the first region z12 of the second surface m2 of the substrate 110, the interface defect state density of the first region z12 on the second surface m2 of the substrate 110 is reduced, thereby reducing the recombination centers in the first region z12 on the second surface m2 of the substrate 110 and lowering the carrier recombination rate. The tunneling layer 121 can be a dielectric material layer. For example, the material of the tunneling layer 121 can be at least one of silicon oxide, magnesium fluoride, silicon oxide, amorphous silicon, polycrystalline silicon, silicon carbide, silicon nitride, silicon oxynitride, aluminum oxide, or titanium oxide. In this embodiment, the tunneling layer 121 can be formed using low-pressure chemical vapor deposition (LPCVD). Of course, other processes such as thermal oxidation, plasma oxidation, or nitric acid oxidation can also be used to fabricate the tunneling layer 121; no specific limitations are imposed here.

[0217] The dopant element of the doped semiconductor layer 122 can be adapted to the conductivity type of the dopant element of the substrate 110. For example, if the substrate 110 is an N-type substrate, the dopant element of the substrate 110 can be phosphorus and / or antimony. The dopant element of the doped semiconductor layer 122 is phosphorus. As another example, if the substrate 110 is a P-type substrate, the dopant element of the doped semiconductor layer 122 is boron. In the embodiments of this application, the dopant element of the doped semiconductor layer 122 is formed by doping amorphous silicon, microcrystalline silicon, polycrystalline silicon, etc., with an N-type dopant element. Exemplarily, the dopant element of the doped semiconductor layer 122 is a phosphorus-doped polycrystalline silicon layer. In this case, the stacked tunneling layer 121 and the doped semiconductor layer 122 together form a passivation contact structure, which provides good surface passivation for the first region z12 of the second surface m2 of the substrate 110.

[0218] Please continue to refer to Figure 1 According to some embodiments of this application, the solar cell 100 further includes a first electrode 150, which is disposed on the side of the first doped region 120a away from the second surface m2 and is electrically connected to the first doped region 120a.

[0219] The first electrode 150 is used to collect and summarize the current of the solar cell 100. The first electrode 150 and the first doped region 120a can be in contact directly or indirectly to form an electrical connection. Exemplarily, the first electrode 150 can be prepared by screen printing and sintering. Exemplarily, the material of the metal paste used to make the first electrode 150 can be one or more of aluminum, silver, gold, nickel, molybdenum or copper, without specific limitation.

[0220] The electrical connection between the first electrode 150 and the first doped region 120a means that, since both the materials of the first electrode 150 and the first doped region 120a are conductive materials, the first electrode 150 and the first doped region 120a form a physical channel for the flow of photogenerated charge carriers through direct or indirect physical contact. When the solar cell 100 is not in a power generation or power supply state, the photogenerated charge carriers are not effectively separated and driven to flow, and the photogenerated charge carriers do not flow through this physical channel. When the first doped region 120a is in a power generation or power supply state, the first doped region 120a generates photogenerated charge carriers, which are separated under the action of its built-in electric field, and the photogenerated charge carriers flow out through this physical channel.

[0221] Please continue to refer to Figure 1 According to some embodiments of this application, the solar cell 100 further includes a second electrode 160, which is disposed on the side of the second doped region 120b opposite to the first surface m1 and is electrically connected to the second doped region 120b. When the second doped region 120b includes a tunneling layer 121 and a doped semiconductor layer 122, the second electrode 160 is electrically linked to the doped semiconductor layer 122. The understanding and implementation of the second electrode 160 can be referred to the first electrode 150, and will not be repeated here.

[0222] It should be noted that the first doped region 120a can adopt either a tunneling passivation structure or a diffusion structure; no specific limitation is made here. For example, one of the first doped region 120a and the second doped region 120b can be a diffusion region, and the other can be a tunneling passivation contact structure. As another example, one of the first doped region 120a and the second doped region 120b can be a first tunneling passivation contact structure, and the other can be a second tunneling passivation contact structure. Figure 1 For example, the first doped region 120a is shown to be a diffusion region, and the second doped region 120b is a tunneling passivation contact structure.

[0223] Please refer to Figure 11 , Figure 11 This is a flowchart illustrating the fabrication method of a solar cell according to some embodiments of this application. According to some embodiments of this application, this application provides a method for fabricating a solar cell, used to fabricate the solar cell in any of the above embodiments. The method for fabricating a solar cell includes:

[0224] Step S110: Provide a first intermediate for a solar cell, the first intermediate for a solar cell including a substrate, a doped region and a first passivation layer;

[0225] Step S120: Perform a first laser treatment on the first intermediate body of the solar cell to form a groove;

[0226] Step S130: Cut along the groove to obtain at least two second intermediate solar cells. Each second intermediate solar cell includes a first surface, a second surface, and a third surface connecting the first surface and the second surface.

[0227] Step S140: Deposit a second passivation layer on the third surface of the second intermediate of the solar cell to form a solar cell.

[0228] In step S120, through the first laser processing, a groove can be formed on the first surface of the first intermediate body of the solar cell, or on the second surface of the first intermediate body of the solar cell, or on both the first and second surfaces of the first intermediate body of the solar cell; no specific limitation is imposed here. When grooves are formed on both the first and second surfaces of the first intermediate body of the solar cell, the grooves on the first surface and the grooves on the second surface may or may not correspond one-to-one in the thickness direction of the first intermediate body of the solar cell. The shapes of the grooves on the first surface and the grooves on the second surface may be the same or different; no specific limitation is imposed here.

[0229] by Figure 12 For example, Figure 12 This is a schematic diagram of the structure of the first intermediate body 101a of the solar cell in some embodiments of this application, illustrating that the groove 1011a is approximately U-shaped. Figure 12 In the illustrated scenario, the grooves 1011a on the first surface and the second surface of the first intermediate body 101a of the solar cell correspond one-to-one in the first direction F1, and the shapes of the grooves 1011a on the first surface and the second surface are the same. The first direction F1 is also the thickness direction of the first intermediate body 101a of the solar cell. The second direction F2 and the third direction F3 can be understood with reference to some of the aforementioned embodiments and will not be described in detail.

[0230] by Figure 13 For example, Figure 13 This is a schematic diagram of the structure of the first intermediate body 101b of the solar cell in some other embodiments of this application, illustrating that the groove 1011b is approximately V-shaped. Figure 13In the illustrated scenario, the grooves 1011b on the first surface and the second surface of the first intermediate body 101b of the solar cell correspond one-to-one in the first direction F1, and the shapes of the grooves 1011b on the first surface and the second surface are the same. The first direction F1 is also the thickness direction of the first intermediate body 101b of the solar cell. The second direction F2 and the third direction F3 can be understood with reference to some of the aforementioned embodiments and will not be described in detail.

[0231] In some other embodiments, when grooves are formed on both the first and second surfaces of the first intermediate body of the solar cell, the groove on the first surface may be approximately U-shaped and the groove on the second surface may be approximately V-shaped; alternatively, the groove on the first surface may be approximately V-shaped and the groove on the second surface may be approximately U-shaped. Of course, the grooves may also be trapezoidal grooves, arc grooves, T-shaped grooves, etc., and no specific limitations are imposed here.

[0232] In step S130, with Figure 12 For example, through the first intermediate 101a of the solar cell, a structure is formed as follows: Figure 14 The second intermediate body 102a of the solar cell shown has a third surface 3a that is a cut surface QG1. Figure 12 In the image, the location of the cutting surface QG1 is indicated by a dashed line. Figure 13 For example, through the first intermediate 101b of the solar cell, a structure is formed as follows: Figure 15 The second intermediate body 102b of the solar cell shown has a third surface 3b that is a cut surface QG2. Figure 13 In the middle, the position of the cutting surface QG2 is indicated by a dashed line.

[0233] It should be noted that, Figure 14 and Figure 15 This is merely an example of a second intermediate in a solar cell, and not a limitation on the structure of a second intermediate formed from a first intermediate in a solar cell. Figure 12 In the illustrated scenario, two second intermediates 102a of the solar cell can be formed. Figure 13 In the illustrated scenario, three second intermediates 102b of solar cells can be formed.

[0234] The third side illustrated in the embodiments of this application can be understood as at least a portion of the side surface of the solar cell illustrated in some of the foregoing embodiments.

[0235] In step S140, a second passivation layer is deposited on the cut surface. Various embodiments of the surface of the second intermediate of the solar cell covered by the formed second passivation layer can be understood with reference to the situation between the second passivation layer, the second region, and the third region illustrated above, and will not be described in detail here.

[0236] Combined with reference Figure 16 , Figure 16 This is a schematic diagram of the structure of a solar cell 103a formed by the second intermediate 102a of a solar cell in some embodiments of this application. A second passivation layer 1031a is deposited on the cut surface QG1 of the second intermediate 102a of the solar cell to form the solar cell 103a.

[0237] Combined with reference Figure 17 , Figure 17 This is a schematic diagram of the structure of a solar cell 103b formed by the second intermediate 102b of a solar cell in other embodiments of this application. A second passivation layer 1031b is deposited on the cut surface QG2 of the second intermediate 102b of the solar cell to form the solar cell 103b.

[0238] Based on the situations illustrated above, through Figure 12 , Figure 14 and Figure 16 The illustrated situation can form, for example Figures 1 to 4 , Figure 8 and Figure 10 The solar cell shown is illustrated. (Through...) Figure 13 , Figure 15 and Figure 17 The illustrated situation can form, for example Figure 5 The solar cell is shown in the diagram. The grooves described above can form the third region in some of the aforementioned embodiments.

[0239] Therefore, on the one hand, by forming a groove through the first laser treatment, the area of ​​the cut surface formed during subsequent cutting is reduced compared to a structure without a groove, thus helping to reduce cutting damage. Furthermore, due to the reduced area of ​​the cut surface, the laser power used during laser cutting can be reduced, further reducing cutting damage. On the other hand, since there is no doped region in the second region of this embodiment, the groove can be considered as being formed in the second region, thus forming a third region. In this process, compared to directly cutting the doped region, not only can damage to the doped region be reduced, but the risk of stress distortion caused by high substrate doping can also be reduced, resulting in better fracture toughness of the substrate and a smoother stress distribution during cutting. This can suppress the initiation and propagation of microcracks and reduce the risk of edge chipping, deep microcracks, and secondary defects caused by melting and resolidification when forming the third region. Therefore, it is beneficial to further reduce damage during the slab cutting process.

[0240] Therefore, in addition to the advantages illustrated in some of the aforementioned embodiments, the solar cells prepared by the above-described method also have the advantages of reducing cutting damage, further reducing the risk of edge recombination, leakage, and edge microcracks, thereby further improving the electrical performance and structural reliability of the solar cells.

[0241] According to some embodiments of this application, the doping element in the doped region is a p-type doping element, and the laser parameters of the first laser processing satisfy at least one of the following: the laser is a pulsed red nanosecond laser; the laser pulse width is 200ns to 500ns; the laser frequency is 33kHz to 200kHz; the laser power is 800W to 2500W; and the laser scanning speed is 30000mm / s to 60000mm / s.

[0242] For example, the laser pulse width can be 200ns, 230ns, 280ns, 300ns, 350ns, 400ns, 430ns, 480ns, or 500ns. The laser pulse width can also be any other value in the range of 200ns to 500ns, without specific limitations.

[0243] For example, the laser frequency can be 33kHz, 40kHz, 50kHz, 60kHz, 70kHz, 80kHz, 100kHz, 120kHz, 150kHz, 170kHz, 180kHz, 190kHz, or 200kHz. The laser frequency can also be any other value in the range of 33kHz to 200kHz, without any specific limitation herein.

[0244] For example, the laser power can be 800W, 850W, 900W, 1000W, 1200W, 1500W, 1700W, 1900W, 2000W, 2200W, or 2500W. The laser power can also be any other value in the range of 800W to 2500W, without any specific limitation.

[0245] For example, the laser scanning speed can be 30,000 mm / s, 35,000 mm / s, 40,000 mm / s, 45,000 mm / s, 5,000 mm / s, 55,000 mm / s, 58,000 mm / s, or 60,000 mm / s. The laser scanning speed can also be any other value in the range of 30,000 mm / s to 60,000 mm / s, without any specific limitation.

[0246] According to some embodiments of this application, the doping element in the doped region is an N-type doping element, and the laser parameters of the first laser processing satisfy at least one of the following: the laser is a green picosecond laser; the laser pulse width is 5 ps to 15 ps; the laser frequency is 1000 kHz to 2000 kHz; the laser power is 200 W to 300 W; and the laser scanning speed is 30000 mm / s to 60000 mm / s.

[0247] For example, the laser is a green picosecond laser with a wavelength of 532nm.

[0248] For example, the laser pulse width can be 5 ps, 6 ps, 7 ps, 8 ps, 9 ps, 10 ps, ​​12 ps, 14 ps, or 15 ps. The laser pulse width can also be any other value in the range of 5 ps to 15 ps, without any specific limitation.

[0249] For example, the laser frequency can be 1000kHz, 1100kHz, 1200kHz, 1300kHz, 1400kHz, 1500kHz, 1600kHz, 1800kHz, or 2000kHz. The laser frequency can also be any other value in the range of 1000kHz to 2000kHz, without any specific limitation.

[0250] For example, the laser power can be 200W, 210W, 220W, 230W, 250W, 270W, 290W, or 300W. The laser power can also be any other value in the range of 200W to 300W, without any specific limitation.

[0251] For example, the laser scanning speed can be 30,000 mm / s, 35,000 mm / s, 40,000 mm / s, 45,000 mm / s, 5,000 mm / s, 55,000 mm / s, 58,000 mm / s, or 60,000 mm / s. The laser scanning speed can also be any other value in the range of 30,000 mm / s to 60,000 mm / s, without any specific limitation.

[0252] Depending on the type of doping element in the doped region, by controlling the laser parameters of the first laser treatment, the groove depth, slope angle and lateral dimensions can be controlled more accurately. In the case that pyramid structures are provided on both the second and third regions shown above, the first laser treatment and the grooves work together to form the differentiated first pyramid structure J1 and second pyramid structure J2 shown above. On the other hand, it can be used in conjunction with the cutting process to further reduce edge defects.

[0253] It should be noted that in some other embodiments, ultraviolet picosecond lasers, green nanosecond lasers, etc., can also be used to create grooves. No specific limitations are imposed here.

[0254] According to some embodiments of this application, the first intermediate of the solar cell is cut using a laser cutting process. The laser parameters of the laser cutting process satisfy at least one of the following: the laser is a pulsed red nanosecond laser; the laser pulse width is 5 ps to 15 ps; the laser frequency is 33 kHz to 200 kHz; the laser power is 1200 W to 2000 W; and the laser scanning speed is 120 mm / s to 400 mm / s.

[0255] For example, the laser is a pulsed red nanosecond laser with a wavelength of 1064 nm.

[0256] For example, the laser pulse width can be 5 ps, 6 ps, 7 ps, 8 ps, 10 ps, ​​11 ps, 13 ps, 14 ps, or 15 ps. The laser pulse width can also be any other value in the range of 5 ps to 15 ps, without any specific limitation.

[0257] For example, the laser frequency can be 33kHz, 40kHz, 50kHz, 60kHz, 70kHz, 90kHz, 110kHz, 120kHz, 150kHz, 160kHz, 180kHz, 190kHz, or 200kHz. The laser frequency can also be any other value in the range of 33kHz to 200kHz, without any specific limitation.

[0258] For example, the laser power can be 1200W, 1300W, 1400W, 1500W, 1600W, 1700W, 1800W, 1900W, or 2000W. The laser power can also be any other value in the range of 1200W to 2000W, without any specific limitation.

[0259] For example, the laser scanning speed can be 120 mm / s, 150 mm / s, 200 mm / s, 220 mm / s, 280 mm / s, 300 mm / s, 320 mm / s, 380 mm / s, or 400 mm / s. The laser scanning speed can also be any other value in the range of 120 mm / s to 400 mm / s, without any specific limitation.

[0260] In this way, by controlling the various laser parameters in the laser cutting process, damage to the substrate can be minimized during cutting.

[0261] Furthermore, the interaction between the first region, second region, third region, and groove in this embodiment helps to broaden the laser cutting process window, thereby allowing for more flexible selection of laser parameters. Therefore, in addition to the laser parameters illustrated above, other implementation methods can be chosen for the laser cutting process to meet the requirements of cutting and reducing damage. For example, a second laser or a visible light laser can be used, without specific limitations. As another example, the laser power can be 100W-1000W, and the laser scanning speed can be 70mm / s to 100mm / s, without specific limitations.

[0262] According to some embodiments of this application, a first intermediate for a solar cell (i.e., step S110) is provided, comprising:

[0263] Step S111: Provide a third intermediate for a solar cell; the third intermediate for a solar cell includes a substrate and an initial doped region disposed on a first surface of the substrate;

[0264] Step S112: Perform a second laser treatment on the second region of the first surface of the substrate to form a doped region in the first region;

[0265] Step S113: Repair the first surface of the first intermediate of the solar cell; the repair treatment includes at least one of texturing treatment and alkaline polishing treatment.

[0266] In step S112, the initial doped region in the second region can be removed by the second laser processing, and a doped region can be formed in the first region.

[0267] Therefore, by combining the second laser treatment with the repair treatment, not only can the aforementioned pyramid-shaped structure or tower-based structure be formed while forming the doped region, but the damage to the substrate caused by the laser treatment can also be reduced.

[0268] According to some embodiments of this application, the doping element in the doped region is a p-type doping element, and the laser parameters of the second laser processing process satisfy at least one of the following: the laser is a pulsed red nanosecond laser; the laser pulse width is 400ns to 700ns; the laser frequency is 66kHz to 300kHz; the laser power is 400W to 2000W; and the laser scanning speed is 60000mm / s to 80000mm / s.

[0269] For example, the laser is a pulsed red nanosecond laser with a wavelength of 1064 nm.

[0270] For example, the laser pulse width can be 400ns, 500ns, 600ns, or 700ns. The laser pulse width can also be any other value in the range of 400ns to 700ns, without any specific limitation.

[0271] For example, the laser frequency can be 66 kHz, 100 kHz, 150 kHz, 200 kHz, 260 kHz, 280 kHz, or 300 kHz. The laser frequency can also be any other value in the range of 66 kHz to 300 kHz, without any specific limitation.

[0272] For example, the laser power can be 400W, 600W, 800W, 1000W, 1200W, 1500W, 1600W, or 2000W. The laser power can also be any other value in the range of 400W to 2000W, without any specific limitation.

[0273] For example, the laser scanning speed can be 60,000 mm / s, 65,000 mm / s, 70,000 mm / s, 75,000 mm / s, or 80,000 mm / s. The laser scanning speed can also be any other value in the range of 60,000 mm / s to 80,000 mm / s, without any specific limitation.

[0274] According to some embodiments of this application, the doping element in the doped region is an N-type doping element, and the laser parameters of the second laser processing process satisfy at least one of the following: the laser is a green picosecond laser; the laser pulse width is 5 ps to 15 ps; the laser frequency is 2000 kHz to 4000 kHz; the laser power is 100 W to 200 W; and the laser scanning speed is 60000 mm / s to 80000 mm / s.

[0275] For example, the laser is a green picosecond laser with a wavelength of 532nm.

[0276] For example, the laser pulse width can be 5 ps, 6 ps, 7 ps, 8 ps, 9 ps, 10 ps, ​​12 ps, 14 ps, or 15 ps. The laser pulse width can also be any other value in the range of 5 ps to 15 ps, without any specific limitation.

[0277] For example, the laser frequency can be 2000kHz, 2500kHz, 3000kHz, 3500kHz, 3800kHz, or 4000kHz. The laser frequency can also be any other value in the range of 2000kHz to 4000kHz, without any specific limitation.

[0278] For example, the laser power can be 100W, 110W, 120W, 140W, 160W, 180W, or 200W. The laser power can also be any other value in the range of 100W to 200W, without any specific limitation.

[0279] For example, the laser scanning speed can be 60,000 mm / s, 65,000 mm / s, 70,000 mm / s, 75,000 mm / s, 78,000 mm / s, or 80,000 mm / s. The laser scanning speed can also be any other value in the range of 60,000 mm / s to 80,000 mm / s, without any specific limitation.

[0280] By controlling the laser parameters of the second laser treatment, based on the doping type of the doping element in the doped region, damage to the substrate can be minimized while forming the doped region.

[0281] It should be noted that the laser used in the second laser processing process can also be an ultraviolet picosecond laser, a green nanosecond laser, etc., and no specific restrictions are made here.

[0282] It should also be noted that, when a third region is provided on the first and second surfaces of the solar cell, the second laser treatment can be performed on the first surface first, followed by the first laser treatment on the first surface, and then the second laser treatment on the second surface first; alternatively, the second laser treatment can be performed on both the first and second surfaces first, followed by the first laser treatment on both the first and second surfaces respectively. No specific limitations are imposed here.

[0283] It is understandable that performing the second laser treatment on the first side, followed by the first laser treatment on the first side, and then performing the second laser treatment on the second side, followed by the first laser treatment on the second side, is more conducive to improving production efficiency and reducing manufacturing costs.

[0284] Please continue to refer to Figure 12According to some embodiments of this application, the depth r1a of the groove 1011a is 1 μm to 3 μm, and the width r2a of the groove 1011a is 5 μm to 10 μm. The depth r1a of the groove 1011a is the dimension of the groove 1011a along the first direction F1. The width r2a of the groove 1011a is the dimension of the groove 1011a along the second direction F2.

[0285] For example, the depth r1a of the groove 1011a can be 1μm, 1.5μm, 2μm, 2.5μm, 2.8μm or 3μm. The depth r1a of the groove 1011a can also be any other value in the range of 1μm to 3μm, and no specific limitation is made here.

[0286] For example, the width r2a of the groove 1011a can be 5μm, 6μm, 7μm, 8μm, 9μm or 10μm. The width r2a of the groove 1011a can also be any other value in the range of 5μm to 10μm, and no specific limitation is made here.

[0287] By controlling the lower limit of the width r2a of the groove 1011a, not only can a process alignment allowance be reserved for subsequent dicing, but also sufficient space can be provided to form the aforementioned first sub-pyramid structure J11 and second sub-pyramid structure J12. This is beneficial for passivation, lengthening the edge penetration and leakage path, and also facilitates the formation of the aforementioned second passivation layer. By controlling the upper limit of the width r2a of the groove 1011a, carrier shunt loss can be reduced while maintaining a certain short-circuit current output, thereby reducing etching loss and processing costs.

[0288] By controlling the lower limit of the depth r1a of the groove 1011a, it is not only beneficial to fully extend the moisture and leakage path and improve the barrier protection capability at the edge, but also to form a clearer morphological benchmark for easier cutting and positioning, thereby gradually releasing cutting stress to suppress crack propagation. Furthermore, it provides structural space for the differentiated design of the first sub-pyramid structure J11 and the second sub-pyramid structure J12. By controlling the upper limit of the depth r1a of the groove 1011a, it is not only possible to reduce the risk of insufficient edge mechanical strength and edge breakage due to excessive etching, but also to suppress additional edge damage such as dislocations and microcracks caused by an excessively large laser heat-affected zone. Simultaneously, it can reduce the risk of passivation film stress cracking and detachment caused by excessive film layer undulation.

[0289] By simultaneously controlling the width range r2a and the depth range r1a of the groove 1011a, in addition to the advantages mentioned above, it can also be used in conjunction with the process of first removing the initial doped region on the second region before forming the groove 1011a in the embodiments of this application, resulting in lower overall edge lattice damage. Furthermore, it can reduce dimensional deviations caused by laser process fluctuations, widen the process window, and thus help improve production consistency and yield.

[0290] It should be noted that, in Figure 13 In the illustrated scenario, the depth r1b of the groove 1011b is also the dimension of the groove 1011b along the first direction F1, and the width r2b of the groove 1011b can be understood as the dimension of the opening of the groove 1011b along the second direction F2. The depth r1b of the groove 1011b is 1μm to 3μm, and the width r2b of the groove 1011b is 5μm to 10μm.

[0291] With a groove depth of 1μm to 3μm and a groove width of 5μm to 10μm, the size of the third region z31 shown above along the first direction F1 is 1μm to 3μm, and the size of the third region z31 along the second direction F2 is 2.5μm to 5μm.

[0292] It should also be noted that the groove may penetrate the first intermediate body of the solar cell along the third direction F3, or it may not penetrate the first intermediate body of the solar cell along the third direction F3. The groove may be a continuous structure or a discontinuous structure. For example, the groove may extend continuously along the third direction F3 to form a continuous structure. Alternatively, the groove may extend discontinuously along the third direction F3 to form a discontinuous structure. No specific limitations are imposed here. In the embodiments of this application, the groove penetrates the first intermediate body of the solar cell along the third direction F3, and the groove extends continuously along the third direction F3.

[0293] Based on the scenarios illustrated in the above embodiments, possible methods for manufacturing solar cells will be described below by way of example, but are not limited thereto.

[0294] For example, please refer to the reference Figure 12 , Figure 14 , Figure 16 ,based on Figure 1 The solar cell shown can be manufactured by means of the following steps:

[0295] Step S11: Perform a texturing process on the first surface of the initial substrate to form a pyramid-shaped structure on the first surface of the initial substrate. Alternatively, perform texturing on the first and second surfaces of the initial substrate to form a pyramid-shaped structure on the first and second surfaces.

[0296] Step S12: Boron doping is performed on the initial substrate to form a PN junction. A boron diffusion region and borosilicate glass are formed sequentially on the first side of the initial substrate, and a boron diffusion region and borosilicate glass are formed sequentially on the second side of the initial substrate.

[0297] Step S13: Perform a second laser treatment on the first surface of the initial substrate to remove the boron diffusion region and borosilicate glass in the second region of the first surface.

[0298] Step S14: Perform texturing on the second region of the first surface of the initial substrate to repair laser damage in the second region.

[0299] Step S15: Introduce oxygen and perform a high-temperature oxidation process.

[0300] Step S16: Clean the side surfaces and the structure of the second surface of the initial substrate using a chain cleaning process, and perform alkaline polishing on the second surface.

[0301] Step S17: Deposit SiO2 on the second surface of the initial substrate to form a tunneling layer, deposit amorphous silicon to form an amorphous silicon layer, and perform phosphorus doping to transform the amorphous silicon layer into a doped polycrystalline silicon layer.

[0302] Step S18: Perform a second laser treatment on the second surface of the initial substrate to remove the tunneling layer and doped polysilicon layer in the second region of the second surface.

[0303] Step S19: Perform texturing to repair laser damage in the second region of the second side, remove oxide layers and other structures on the first and second sides, form a boron diffusion region (i.e., the first doped region) in the first region of the first side, and form a tunneling layer and a doped polysilicon layer (i.e., the second doped region) in the first region of the second side.

[0304] Step S20: Deposit a first passivation layer. The first passivation layer covers the side of the first doped region away from the second surface, the side of the second doped region away from the first surface, and the remaining surface of the initial substrate to form a first intermediate of the solar cell.

[0305] Step S21: Perform a first laser treatment on the first intermediate body of the solar cell to form grooves on the first and second surfaces.

[0306] Step S22: Cut along the groove to obtain two second intermediate solar cells. Each second intermediate solar cell includes a first surface, a second surface, and a third surface connecting the first and second surfaces. The third surface is the cutting surface and also the side surface of the second intermediate solar cell. A portion of the groove wall forms the third region of one of the second intermediate solar cells, and another portion of the groove wall forms the third region of the other second intermediate solar cell.

[0307] Step S23: Deposit a second passivation layer on the third surface of the second intermediate of the solar cell. The second passivation layer is disposed on the third surface and the first passivation layer located on the third region is on the side opposite to the substrate.

[0308] Step S24: The first electrode and the second electrode are formed by screen printing and sintering processes to obtain a solar cell.

[0309] In step S19 illustrated above, a pyramid-shaped structure or a base structure may also be formed in the second region; no specific limitation is made here. Furthermore, in some other embodiments, other fabrication processes may be used to fabricate the solar cell; this embodiment is not limited to these methods.

[0310] According to some embodiments of this application, this application provides a tandem solar cell, including a bottom cell and a top cell stacked on the bottom cell; wherein the bottom cell includes the solar cell in any of the above embodiments; or, the bottom cell includes a solar cell manufactured by the method of manufacturing the solar cell in any of the above embodiments.

[0311] For example, the top cell can be one of a perovskite cell, a cadmium telluride solar cell, a copper indium gallium selenide solar cell, or a gallium arsenide solar cell.

[0312] For example, the stacked battery also includes a connecting layer that connects the bottom battery and the top battery.

[0313] For the selection of the interconnect layer, a transparent material with a high refractive index is typically chosen. The interconnect layer needs to have high light transmittance to reduce light reflection and absorption at the interconnect layer interface, and good conductivity to reduce the impact of series resistance on device performance. For example, transparent conductive metal oxide thin films (ITO) can be used as interconnect layers, and no specific limitation is made here.

[0314] The advantages of solar cells and solar cell manufacturing methods described above are also present in tandem solar cells, and will not be elaborated upon here.

[0315] According to some embodiments of this application, please refer to Figure 18 , Figure 18 This is a schematic diagram of the structure of a photovoltaic module 10 in some embodiments of this application. The embodiments of this application provide a photovoltaic module 10, including a solar cell in any of the above embodiments; or a solar cell manufactured by the method of manufacturing a solar cell in any of the above embodiments; or a tandem cell in any of the above embodiments.

[0316] Furthermore, the solar cells can be electrically connected in the form of multiple segments to form multiple cell strings 11, and the multiple cell strings 11 are electrically connected in series and / or parallel.

[0317] In some embodiments, the photovoltaic module 10 further includes an encapsulation layer 12 and a cover plate 13, wherein the encapsulation layer 12 is used to cover the surface of the battery string 11, and the cover plate 13 is used to cover the surface of the encapsulation layer 12 away from the battery string 11.

[0318] In some embodiments, multiple cell strings 11 can be electrically connected via conductive strips 14. An encapsulation layer 12 covers both the front and back sides of the solar cell.

[0319] In some embodiments, the encapsulation layer 12 may be an organic encapsulation film such as ethylene-vinyl acetate copolymer (EVA) film, polyethylene octene coelastomer (POE) film, or polyethylene terephthalate (PET) film.

[0320] In some embodiments, the cover plate 13 can be a glass cover plate, a plastic cover plate, or other cover plate with light transmission function.

[0321] In some embodiments, the surface of the cover plate 13 facing the encapsulation layer 12 can be an uneven surface, thereby increasing the utilization rate of incident light.

[0322] The photovoltaic module 10 also possesses the advantages of the solar cells, the manufacturing methods of solar cells, and the tandem cells described above, and will not be repeated here.

[0323] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0324] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A solar cell, characterized in that, include: The substrate has a first surface and a second surface that are arranged opposite to each other; the first surface is divided into alternating first regions and second regions; wherein the first surface is further divided into a third region, the third region is located at the edge of the first surface and adjacent to the second region, the distance between the first region and the second surface is H1, the distance between the second region and the second surface is H2, and the distance between the third region and the second surface is H3, where H1 > H2 and H2 > H3; A doped region is located in the first region; A first passivation layer is disposed on the side of the doped region opposite to the second surface, on the second region, and on the third region; and The second passivation layer is disposed on the side of the first passivation layer located on the third region that is opposite to the first surface; The third region is provided with a first pyramid-shaped structure, and the second region is provided with a second pyramid-shaped structure. The height of the first pyramid-shaped structure is less than or equal to the height of the second pyramid-shaped structure; and / or, the one-dimensional dimension of the first pyramid-shaped structure is less than or equal to the one-dimensional dimension of the second pyramid-shaped structure.

2. The solar cell according to claim 1, characterized in that, Define the second region adjacent to the third region as the target region; The second passivation layer is also disposed on the side of the first passivation layer opposite to the first surface located on the target region, and the second passivation layer located on the target region is connected to the second passivation layer located on the third region.

3. The solar cell according to claim 1, characterized in that, The substrate also has a side surface connecting the first surface and the second surface, and the second passivation layer is also disposed on the side surface.

4. The solar cell according to any one of claims 1-3, characterized in that, The doping element in the doped region is defined as the first doping element; The doping concentration of the first dopant element in the doping region is N1, the doping concentration of the first dopant element in the second region is N2, and the doping concentration of the first dopant element in the third region is N3, where N1 > N2 and N2 ≥ N3.

5. The solar cell according to claim 4, characterized in that, The doping type of the first doped element is the same as the doping type of the substrate; N1 is 5 × 10 19 cm -3 Up to 5×10 20 cm -3 .

6. The solar cell according to claim 5, characterized in that, N2 is 1×10 16 cm -3 Up to 1×10 19 cm -3 N3 is 1×10 15 cm -3 Up to 1×10 16 cm -3 .

7. The solar cell according to claim 4, characterized in that, The doping type of the first doped element is different from the doping type of the substrate; N1 is 5 × 10 15 cm -3 Up to 5×10 16 cm -3 .

8. The solar cell according to claim 7, characterized in that, N2 is 1×10 16 cm -3 Up to 1×10 18 cm -3 .

9. The solar cell according to any one of claims 1-3, characterized in that, The third region includes a first side that connects to the corresponding second region, and a second side that is opposite to the first side and far away from the second region; The third region extends from the first side to the second side and is inclined relative to the corresponding second region.

10. The solar cell according to any one of claims 1-3, characterized in that, The third region includes a connected first sub-region and a second sub-region, wherein the side of the first sub-region away from the second sub-region is connected to the corresponding second region. The first sub-region and the second sub-region define the recess.

11. The solar cell according to any one of claims 1-3, characterized in that, The gap between two adjacent first pyramid-shaped structures is less than or equal to the gap between two adjacent second pyramid-shaped structures.

12. The solar cell according to any one of claims 1-3, characterized in that, The height of the first pyramidal structure is 0.5 μm to 1.5 μm, and the height of the second pyramidal structure is 1.5 μm to 2.5 μm; and / or The first pyramidal structure has a one-dimensional dimension of 2 μm to 5 μm, and the second pyramidal structure has a one-dimensional dimension of 4 μm to 6 μm; and / or The gap between two adjacent first pyramid-shaped structures is 1 μm to 3 μm, and the gap between two adjacent second pyramid-shaped structures is 2 μm to 4 μm.

13. The solar cell according to any one of claims 1-3, characterized in that, The third region includes a first sub-region and a second sub-region, the first sub-region connecting the second region and the second sub-region, and the first sub-region and the second sub-region defining a recess; The first pyramid-shaped structure includes a first sub-pyramid-shaped structure disposed on the first sub-region and a second sub-pyramid-shaped structure disposed on the second sub-region.

14. The solar cell according to claim 13, characterized in that, The height of the first sub-pyramid structure is greater than or equal to the height of the second sub-pyramid structure; and / or The one-dimensional dimension of the first sub-pyramid structure is greater than or equal to the one-dimensional dimension of the second sub-pyramid structure; and / or The gap between two adjacent first sub-pyramid structures is greater than or equal to the gap between two adjacent second sub-pyramid structures.

15. The solar cell according to claim 13, characterized in that, The height of the first sub-pyramid structure is 0.8 μm to 1.5 μm, and the height of the second sub-pyramid structure is 0.5 μm to 1 μm; and / or The first sub-pyramid structure has a one-dimensional dimension of 3 μm to 5 μm, and the second sub-pyramid structure has a one-dimensional dimension of 2 μm to 4 μm; and / or The gap between two adjacent first sub-pyramid structures is 1.5 μm to 3 μm, and the gap between two adjacent second sub-pyramid structures is 1 μm to 2 μm.

16. A method for manufacturing a solar cell, characterized in that, A method for manufacturing a solar cell as described in any one of claims 1-15, comprising: A first intermediate for a solar cell is provided, the first intermediate for a solar cell comprising a substrate, a doped region, and a first passivation layer; The first intermediate of the solar cell is subjected to a first laser treatment to form a groove; The first intermediate body of the solar cell is cut along the groove to obtain at least two second intermediate bodies of the solar cell. Each second intermediate body of the solar cell includes a first surface, a second surface, and a third surface connecting the first surface and the second surface. A second passivation layer is deposited on the third surface of the second intermediate of the solar cell to form the solar cell.

17. The method for manufacturing a solar cell according to claim 16, characterized in that, The step of cutting the first intermediate of the solar cell is performed by laser cutting. The laser parameters of the laser cutting process satisfy at least one of the following: The laser is a pulsed red nanosecond laser; the laser pulse width is 5ps to 15ps; the laser frequency is 33kHz to 200kHz; the laser power is 1200W to 2000W; and the laser scanning speed is 120mm / s to 400mm / s.

18. A stacked battery, characterized in that, It includes a bottom battery and a top battery stacked on the bottom battery; Wherein, the bottom battery comprises a solar cell as described in any one of claims 1-15; or The bottom cell includes a solar cell manufactured by the method of manufacturing a solar cell as described in claim 16 or 17.

19. A photovoltaic module, characterized in that, include: Solar cells as described in any one of claims 1-15; or A solar cell manufactured by the method of manufacturing a solar cell as described in claim 16 or 17; or The stacked battery as described in claim 18.

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