Solar cell and photovoltaic module

Abstract

The invention relates to a solar cell and a photovoltaic module. The solar cell comprises a semiconductor substrate which is provided with a first surface and a second surface which are oppositely arranged; the first intrinsic semiconductor layer is arranged on the first surface; the first doping layer is arranged on one side, deviating from the semiconductor substrate, of the first intrinsic semiconductor layer; wherein the projection area of the orthographic projection of the first doping layer on the semiconductor substrate is smaller than the projection area of the orthographic projection of the first surface on the semiconductor substrate. Therefore, according to the solar cell and the photovoltaic module provided by the invention, the conversion efficiency of the solar cell can be improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, in particular to solar cells and photovoltaic modules. Background Art

[0002] Solar cells, also known as photovoltaic cells, are semiconductor devices that convert sunlight directly into electrical energy. As they are green and environmentally friendly products that do not cause environmental pollution, and solar energy is a renewable resource, solar cells are a new type of battery with broad development prospects.

[0003] Among the related technologies, heterojunction cells have the advantages of simple structure, low process temperature, good passivation effect, high open circuit voltage, good temperature characteristics, and double-sided power generation. They are one of the hot directions of high-conversion-efficiency silicon-based solar cells.

[0004] However, the conversion efficiency of the above heterojunction solar cells needs to be improved. Summary of the invention

[0005] Based on this, it is necessary to provide a solar cell and a photovoltaic module to improve the conversion efficiency of the solar cell.

[0006] In a first aspect, an embodiment of the present application provides a solar cell, comprising:

[0007] A semiconductor substrate having a first surface and a second surface arranged opposite to each other;

[0008] A first intrinsic semiconductor layer, disposed on the first surface;

[0009] A first doped layer is disposed on a side of the first intrinsic semiconductor layer away from the semiconductor substrate;

[0010] The projection area of ​​the orthographic projection of the first doped layer on the semiconductor substrate is smaller than the projection area of ​​the orthographic projection of the first surface on the semiconductor substrate.

[0011] In the solar cell provided in the embodiment of the present application, the projection area of ​​the orthographic projection of the first doped layer on the semiconductor substrate is smaller than the projection area of ​​the orthographic projection of the first surface on the semiconductor substrate. By reducing the setting area of ​​the first doped layer, the coverage range of the first doped layer can be reduced, so as to reduce the absorption of light by the first doped layer, thereby improving the conversion efficiency of the solar cell.

[0012] In one of the embodiments, an orthographic projection of the first doped layer on the semiconductor substrate has a first distance from an outer contour of an orthographic projection of the first surface on the semiconductor substrate.

[0013] In one embodiment, the first spacing is less than or equal to 5 mm.

[0014] In one embodiment, the ratio of the projection area of ​​the orthographic projection of the first doped layer on the semiconductor substrate to the projection area of ​​the orthographic projection of the first surface on the semiconductor substrate is α, and α satisfies the condition: α≥55%.

[0015] In one embodiment, the solar cell includes a first conductive layer, which is disposed on a side of the first doped layer facing away from the semiconductor substrate;

[0016] The first conductive layer includes a first sub-portion and a second sub-portion, and an orthographic projection of the first sub-portion on the semiconductor substrate overlaps with an orthographic projection of the first doped layer on the semiconductor substrate;

[0017] An orthographic projection of at least a portion of the second sub-portion on the semiconductor substrate does not overlap with an orthographic projection of the first doped layer on the semiconductor substrate.

[0018] In one embodiment, the conductivity of the first conductive layer is greater than the conductivity of the first doped layer; and / or,

[0019] The light transmittance of the first conductive layer is greater than the light transmittance of the first doped layer.

[0020] In one embodiment, the conductivity of the first subsection is greater than the conductivity of the second subsection; and / or,

[0021] The material of the first sub-portion includes indium compound.

[0022] In one embodiment, the material of the first sub-portion includes indium, and the indium content of the first sub-portion is greater than the indium content of the second sub-portion.

[0023] In one embodiment, the material of the first sub-portion includes indium tin oxide;

[0024] The material of the second sub-portion includes at least one of an indium-free transparent conductive oxide and a transparent insulating material.

[0025] In one embodiment, the first doped layer includes a plurality of first doped portions arranged at intervals along a first direction, and the first direction is perpendicular to a thickness direction of the semiconductor substrate;

[0026] There are a plurality of first sub-sections, and the plurality of first doped sections are arranged corresponding to the plurality of first sub-sections;

[0027] An orthographic projection of the first sub-portion on the semiconductor substrate overlaps with an orthographic projection of the corresponding first doped portion on the semiconductor substrate.

[0028] In one embodiment, the orthographic projection of the first sub-portion on the semiconductor substrate is located within the orthographic projection of the corresponding first doped portion on the semiconductor substrate;

[0029] Alternatively, the orthographic projection of the first doped portion on the semiconductor substrate is located within the orthographic projection of the corresponding first sub-portion on the semiconductor substrate, and a portion of the first sub-portion covers the sidewall of the first doped portion.

[0030] In one embodiment, the solar cell includes a plurality of first electrodes arranged at intervals along a first direction, and the first electrodes are located on a side of the first conductive layer away from the semiconductor substrate;

[0031] The plurality of first electrodes are arranged corresponding to the plurality of first sub-portions, and the orthographic projections of the first electrodes on the semiconductor substrate are located within the orthographic projections of the corresponding first sub-portions on the semiconductor substrate.

[0032] In one embodiment, the first doping portion includes at least one first sub-doping portion and at least one second sub-doping portion, and the first sub-doping portion and the second sub-doping portion are alternately arranged along the first direction;

[0033] The orthographic projection of the first electrode on the semiconductor substrate is located within the orthographic projection of the first sub-doped portion on the semiconductor substrate, and does not overlap with the orthographic projection of the second sub-doped portion on the semiconductor substrate.

[0034] In one of the embodiments, the first doping portion includes a plurality of second sub-doping portions;

[0035] The dimension of the first sub-doping portion along the thickness direction of the semiconductor substrate is smaller than the dimension of the second sub-doping portion along the thickness direction of the semiconductor substrate, and a first groove is formed between two adjacent second sub-doping portions;

[0036] A first protrusion is disposed on a side of the first sub-portion facing the first doping portion, and the first protrusion is engaged with the first groove.

[0037] In one embodiment, the crystallization rate of the first sub-doping portion is greater than the crystallization rate of the second sub-doping portion.

[0038] In one embodiment, the first sub-doping portion and the second sub-doping portion are both doped with oxygen, and the oxygen content of the first sub-doping portion is less than the oxygen content of the second sub-doping portion.

[0039] In one embodiment, a dimension of the first electrode along the first direction is greater than or equal to 20 μm; and / or,

[0040] A size of the first doped portion along the first direction ranges from 0.385 mm to 5.775 mm.

[0041] In one embodiment, a dimension of the first groove along a thickness direction of the semiconductor substrate is less than or equal to 15 μm; and / or,

[0042] A dimension of the first groove along the first direction is greater than or equal to 20 μm.

[0043] In one embodiment, in the same first doping portion, a ratio of a sum of projection areas of orthographic projections of all first sub-doping portions on the semiconductor substrate to a projection area of ​​an orthographic projection of the first doping portion on the semiconductor substrate is in a range of 78%-99%.

[0044] In one embodiment, the crystallization rate of the first sub-doped portion is in the range of 40%-60%; and / or,

[0045] The crystallization rate of the second sub-doping portion is less than or equal to 40%; and / or,

[0046] The difference between the crystallization rate of the first sub-doping portion and the crystallization rate of the second sub-doping portion is less than or equal to 60%; and / or,

[0047] The oxygen content of the first sub-doping portion is less than or equal to 2%; and / or,

[0048] The oxygen content of the second sub-doping portion is in the range of 2%-5%; and / or,

[0049] The difference between the oxygen content of the second sub-doping portion and the oxygen content of the first sub-doping portion is less than or equal to 5%.

[0050] In one embodiment, the orthographic projection of the first surface on the semiconductor substrate is located within the orthographic projection of the first conductive layer on the semiconductor substrate, and a portion of the first conductive layer covers the sidewall of the semiconductor substrate.

[0051] In one embodiment, the solar cell includes a second intrinsic semiconductor layer and a second doped layer, the second intrinsic semiconductor layer is disposed on the second surface, and the second doped layer is disposed on a side of the second intrinsic semiconductor layer away from the semiconductor substrate;

[0052] The projection area of ​​the orthographic projection of the second doped layer on the semiconductor substrate is smaller than the projection area of ​​the orthographic projection of the second surface on the semiconductor substrate.

[0053] In one of the embodiments, an orthographic projection of the second doped layer on the semiconductor substrate has a second distance from an outer contour of an orthographic projection of the second surface on the semiconductor substrate.

[0054] In one embodiment, the second distance is less than or equal to 5 mm.

[0055] In one embodiment, the solar cell includes a second conductive layer, the second conductive layer is disposed on a side of the second doped layer away from the semiconductor substrate, and the second conductive layer includes a third sub-portion and a fourth sub-portion;

[0056] The orthographic projection of the third sub-portion on the semiconductor substrate overlaps with the orthographic projection of the second doped layer on the semiconductor substrate, and the orthographic projection of at least part of the fourth sub-portion on the semiconductor substrate does not overlap with the orthographic projection of the second doped layer on the semiconductor substrate.

[0057] In one embodiment, the second doped layer includes a plurality of second doped portions arranged at intervals along a first direction, and the first direction is perpendicular to a thickness direction of the semiconductor substrate;

[0058] There are multiple third sub-sections, and the multiple second doped sections are arranged correspondingly to the multiple third sub-sections. The orthographic projection of the third sub-section on the semiconductor substrate overlaps with the orthographic projection of the corresponding second doped section on the semiconductor substrate.

[0059] In one embodiment, the solar cell includes a plurality of second electrodes arranged at intervals along a first direction, and the second electrodes are located on a side of the second conductive layer away from the semiconductor substrate;

[0060] The plurality of second electrodes are arranged corresponding to the plurality of third sub-portions, and the orthographic projections of the second electrodes on the semiconductor substrate are located within the orthographic projections of the corresponding third sub-portions on the semiconductor substrate.

[0061] In one embodiment, the second doping portion includes at least one third sub-doping portion and at least one fourth sub-doping portion, and the third sub-doping portion and the fourth sub-doping portion are alternately arranged along the first direction;

[0062] The orthographic projection of the second electrode on the semiconductor substrate is located within the orthographic projection of the third sub-doping portion on the semiconductor substrate, and does not overlap with the orthographic projection of the fourth sub-doping portion on the semiconductor substrate.

[0063] In one embodiment, the second doping portion includes a plurality of fourth sub-doping portions, the dimension of the third sub-doping portion along the thickness direction of the semiconductor substrate is smaller than the dimension of the fourth sub-doping portion along the thickness direction of the semiconductor substrate, a second groove is formed between two adjacent fourth sub-doping portions, a second protrusion is provided on a side of the third sub-portion facing the second doping portion, and the second protrusion is engaged with the second groove; and / or,

[0064] The crystallization rate of the third sub-doping portion is greater than the crystallization rate of the fourth sub-doping portion; and / or,

[0065] The third sub-doping portion and the fourth sub-doping portion are both doped with oxygen, and the oxygen content of the third sub-doping portion is less than the oxygen content of the fourth sub-doping portion.

[0066] In one of the embodiments, there is a third distance between an orthographic projection of the second conductive layer on the semiconductor substrate and an outer contour of an orthographic projection of the second surface on the semiconductor substrate.

[0067] In one embodiment, the third distance is less than or equal to 5 mm.

[0068] In a second aspect, an embodiment of the present application provides a photovoltaic module, comprising the solar cell in the above-mentioned first aspect.

[0069] The photovoltaic module provided in the embodiment of the present application includes a solar cell, and the projection area of ​​the orthographic projection of the first doped layer on the semiconductor substrate is smaller than the projection area of ​​the orthographic projection of the first surface on the semiconductor substrate. By reducing the setting area of ​​the first doped layer, the coverage range of the first doped layer can be reduced, so as to reduce the absorption of light by the first doped layer, thereby improving the conversion efficiency of the solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 A cross-sectional view of a solar cell provided in an embodiment of the present application.

[0071] Figure 2 Another cross-sectional view of a solar cell provided in an embodiment of the present application.

[0072] Figure 3 Another cross-sectional view of a solar cell provided in an embodiment of the present application.

[0073] Figure 4 A partial cross-sectional view of a solar cell provided in an embodiment of the present application.

[0074] Figure 5 Another cross-sectional view of a solar cell provided in an embodiment of the present application.

[0075] Figure 6 A schematic structural diagram of the corresponding first doped portion, first sub-portion and first electrode provided in an embodiment of the present application.

[0076] Figure 7 Another structural schematic diagram of the corresponding first doped portion, first sub-portion and first electrode provided in an embodiment of the present application.

[0077] Figure 8 Another structural schematic diagram of the corresponding first doped portion, first sub-portion and first electrode provided in an embodiment of the present application.

[0078] Fig. 9 Another structural schematic diagram of the corresponding first doped portion, first sub-portion and first electrode provided in an embodiment of the present application.

[0079] Fig.10 A schematic structural diagram of the corresponding second doping portion, third sub-portion and second electrode provided in an embodiment of the present application.

[0080] Fig.11 Another structural schematic diagram of the corresponding second doping portion, third sub-portion and second electrode provided in an embodiment of the present application.

[0081] Fig.12 Another cross-sectional view of a solar cell provided in an embodiment of the present application.

[0082] Description of reference numerals:

[0083] 100, solar cell; 110, first doped layer; 110a, first doped portion; 111, first sub-doped portion; 112, second sub-doped portion; 1131, first groove; 120, second doped layer; 120a, second doped portion; 123, third sub-doped portion; 124, fourth sub-doped portion; 1252, second groove; 131, first conductive layer; 132, second conductive layer; 141, first sub-portion; 1411, first raised portion; 142, second sub-portion; 143, third sub-portion; 1432, second raised portion; 144, fourth sub-portion; 160, semiconductor substrate; 161, first surface; 162, second surface; 171, first intrinsic semiconductor layer; 172, second intrinsic semiconductor layer; 181, first electrode; 182, first electrode. DETAILED DESCRIPTION

[0084] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0085] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0086] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0087] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0088] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0089] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, 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 implementation method.

[0090] In the related art, a heterojunction battery includes a semiconductor substrate having a first surface and a second surface arranged opposite to each other along a thickness direction. Along the direction away from the semiconductor substrate, the first surface is sequentially provided with a first intrinsic amorphous silicon layer, an N-type amorphous silicon layer, a first conductive layer and a first electrode, and the second surface is sequentially provided with a second intrinsic amorphous silicon layer, a P-type amorphous silicon layer, a second conductive layer and a second electrode.

[0091] However, when the N-type amorphous silicon layer is deposited, it not only covers the first surface but also may cover the side wall of the semiconductor substrate. When the P-type amorphous silicon layer is deposited, it not only covers the second surface but also may cover the side wall of the semiconductor substrate. The coverage area of ​​the N-type amorphous silicon layer and the P-type amorphous silicon layer is large, and the absorption coefficient of the N-type amorphous silicon layer and the P-type amorphous silicon layer is high, resulting in the N-type amorphous silicon layer and the P-type amorphous silicon layer absorbing more light, thereby resulting in a low conversion efficiency of the heterojunction battery. In addition, when the N-type amorphous silicon layer and the P-type amorphous silicon layer are deposited on the side wall of the semiconductor substrate, a parasitic PN junction diode will be formed on the side wall of the semiconductor substrate, resulting in leakage.

[0092] To solve the above problems, the embodiments of the present application provide a solar cell and a photovoltaic module, which can reduce the absorption of light by the first doping layer to improve the conversion efficiency of the solar cell.

[0093] The following will be combined Figure 1-Figure 12 The solar cell 100 and the photovoltaic module provided in the embodiments of the present application are described.

[0094] The embodiment of the present application provides a solar cell 100, which may include a heterojunction cell (homojunction solar cell, referred to as HJT), an interdigitated back contact cell (interdigitated back contact, referred to as IBC), a heterojunction back contact cell (heterojunction back contact, referred to as HBC) or a tunnel oxide passivating contact cell (tunnel oxide passivating contact, referred to as TOPCON), etc. The embodiment of the present application is described by taking a heterojunction cell as an example.

[0095] See also Figure 1 The solar cell 100 includes a semiconductor substrate 160, which can provide support for the film layers to be formed subsequently. The semiconductor substrate 160 can be used to receive incident light and generate photogenerated carriers.

[0096] For example, see Figure 1 The semiconductor substrate 160 may have a first surface 161 and a second surface 162 that are arranged opposite to each other along the thickness direction (i.e., the third direction Z) of the semiconductor substrate 160, and at least one of the first surface 161 and the second surface 162 may be used to receive sunlight. The embodiment of the present application is described by taking the first surface 161 being used to receive sunlight as an example, that is, the first surface 161 is close to the light-facing surface of the solar cell 100, and the second surface 162 is close to the backlight surface of the solar cell 100.

[0097] For example, the semiconductor substrate 160 may be a silicon substrate, and the material of the silicon substrate may include at least one of single crystal silicon, polycrystalline silicon, amorphous silicon and microcrystalline silicon. The present application embodiment is described by taking single crystal silicon as an example.

[0098] Exemplarily, the doping type of the semiconductor substrate 160 may be N-type doping, which may be achieved by doping N-type ions, and the N-type ions may include at least one of phosphorus, arsenic, and antimony. Alternatively, the doping type of the semiconductor substrate 160 may be P-type doping, which may be achieved by doping P-type ions, and the P-type ions may include at least one of aluminum and boron. The embodiment of the present application is described by taking the doping type of the semiconductor substrate 160 as N-type doping as an example.

[0099] In some embodiments, at least one of the first surface 161 and the second surface 162 may have a velvet structure. The velvet structure may be a pyramid velvet, an etched pit velvet, etc. The velvet structure has a low reflectivity to incident light, and thus has a high absorption utilization rate to incident light, so that the photoelectric conversion efficiency of the solar cell 100 is high. In other embodiments, at least one of the first surface 161 and the second surface 162 may not have a velvet structure.

[0100] See also Figure 1 The solar cell 100 includes a first doping layer 110 , which is disposed on the first surface 161 . The first doping layer 110 has a relatively low resistance, and can effectively reduce current loss and increase conductivity.

[0101] Exemplarily, the thickness of the first doping layer 110 may range from 10 μm to 30 μm. For example, the thickness of the first doping layer 110 may be 10 μm, 20 μm, 30 μm, or any value between 10 μm and 30 μm.

[0102] See also Figure 1 The solar cell 100 includes a second doping layer 120, and the second doping layer 120 is disposed on the second surface 162. The second doping layer 120 has a relatively low resistance, and can effectively reduce the current loss and increase the conductivity.

[0103] Exemplarily, the doping type of the second doping layer 120 is opposite to the doping type of the first doping layer 110. The doping type of one of the first doping layer 110 and the second doping layer 120 may be N-type doping, and the doping type of the other may be P-type doping. The embodiment of the present application is described by taking the doping type of the first doping layer 110 as N-type doping and the doping type of the second doping layer 120 as P-type doping as an example.

[0104] Exemplarily, the thickness of the second doping layer 120 may range from 10 μm to 30 μm. For example, the thickness of the second doping layer 120 may be 10 μm, 20 μm, 30 μm, or any value between 10 μm and 30 μm.

[0105] In some embodiments, see Figure 1 and Figure 3 The projection area of ​​the orthographic projection of the first doping layer 110 on the semiconductor substrate 160 is smaller than the projection area of ​​the orthographic projection of the first surface 161 on the semiconductor substrate 160. By reducing the setting area of ​​the first doping layer 110, the coverage of the first doping layer 110 can be reduced to reduce the absorption of light by the first doping layer 110, thereby improving the conversion efficiency of the solar cell 100.

[0106] In some embodiments, see Figure 2 and Figure 3 The projection area of ​​the orthographic projection of the second doping layer 120 on the semiconductor substrate 160 is smaller than the projection area of ​​the orthographic projection of the second surface 162 on the semiconductor substrate 160. By reducing the setting area of ​​the second doping layer 120, the coverage of the second doping layer 120 can be reduced, and the absorption of light by the second doping layer 120 can be reduced, thereby improving the conversion efficiency of the solar cell 100.

[0107] The coverage of at least one of the first doping layer 110 and the second doping layer 120 can be reduced by reducing the area of ​​at least one of the first doping layer 110 and the second doping layer 120, so as to reduce the absorption of light by at least one of the first doping layer 110 and the second doping layer 120, thereby improving the conversion efficiency of the solar cell 100. The embodiment of the present application is described by taking the case where the area of ​​the first doping layer 110 and the second doping layer 120 is reduced at the same time as an example.

[0108] The first doping layer 110 and the first conductive layer 131 provided in the embodiment of the present application are further described below.

[0109] In some embodiments, see Figure 3 There is a distance (i.e., a first distance D1) between the orthographic projection of the first doped layer 110 on the semiconductor substrate 160 and the outer contour of the orthographic projection of the first surface 161 on the semiconductor substrate 160, thereby reducing the setting area of ​​the first doped layer 110. In addition, a distance is provided between the first doped layer 110 and the side wall of the semiconductor substrate 160, which is beneficial to prevent the first doped layer 110 from being formed on the side wall of the semiconductor substrate 160, thereby preventing a parasitic PN junction diode from being formed on the side wall of the semiconductor substrate 160, thereby fundamentally preventing leakage caused by the parasitic PN junction diode.

[0110] For example, the first distance D1 may be less than or equal to 5 mm, thereby preventing the first distance D1 from being too large, which is beneficial to improving the arrangement flexibility of the first doping layer 110. For example, the first distance D1 may be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, or any value less than 5 mm.

[0111] Exemplarily, the ratio of the projection area of ​​the orthographic projection of the first doped layer 110 on the semiconductor substrate 160 to the projection area of ​​the orthographic projection of the first surface 161 on the semiconductor substrate 160 is α, and α is ≥ 55%, so that the area of ​​the first doped layer 110 can be prevented from being too small, which can facilitate current transmission. For example, α can be 55%, 60%, 80%, 90%, or any value greater than 55%.

[0112] In some embodiments, see Figure 3 The solar cell 100 includes a first conductive layer 131, which is disposed on a side of the first doped layer 110 away from the semiconductor substrate 160. The first conductive layer 131 can collect the current generated by the battery and transmit it to the first electrode 181. In addition, the first conductive layer 131 can also have an anti-reflection effect.

[0113] Exemplarily, the conductivity of the first conductive layer 131 is greater than the conductivity of the first doping layer 110 , thereby facilitating the collection and transmission of current.

[0114] Exemplarily, the light transmittance of the first conductive layer 131 is greater than the light transmittance of the first doping layer 110 , which is beneficial for light transmission and improves the conversion efficiency of the solar cell 100 .

[0115] In some embodiments, see Figure 5 The first conductive layer 131 may include a first sub-portion 141 and a second sub-portion 142. The orthographic projection of the first sub-portion 141 on the semiconductor substrate 160 overlaps with the orthographic projection of the first doping layer 110 on the semiconductor substrate 160. Thus, the first sub-portion 141 and the first doping layer 110 are at least partially arranged opposite to each other in the thickness direction of the semiconductor substrate 160, so that the transmission path of the current between the first doping layer 110 and the first sub-portion 141 is short, which is conducive to the transmission of the current. In addition, the orthographic projection of at least part of the second sub-portion 142 on the semiconductor substrate 160 does not overlap with the orthographic projection of the first doping layer 110 on the semiconductor substrate 160. Thus, the second sub-portion 142 and the first doping layer 110 are at least partially staggered in the thickness direction of the semiconductor substrate 160, so that the second sub-portion 142 has a small influence on the current collection capability of the first conductive layer 131. When the second sub-portion 142 is arranged, the material of the second sub-portion 142 can be set to a conductive or non-conductive material, so that the material selection range of the second sub-portion 142 can be expanded.

[0116] in, Figure 4 The path of a carrier (eg, electron e) is shown, and the electron e passes through the second doped portion 120 a, the second conductive layer 132 , and the second electrode 182 in sequence.

[0117] Exemplarily, both the first sub-portion 141 and the second sub-portion 142 may have an anti-reflection effect.

[0118] Exemplarily, the conductivity of the first sub-portion 141 is greater than the conductivity of the second sub-portion 142 , and the conductivity of the first sub-portion 141 is set to be larger, thereby facilitating current transmission.

[0119] Exemplarily, the material of the first sub-section 141 is different from the material of the second sub-section 142. For example, the material of the first sub-section 141 includes indium, wherein indium (In) is a rare metal and the indium content in the earth's crust is rare, resulting in high price and high cost of indium. By making the indium content of the first sub-section 141 greater than the indium content of the second sub-section 142, that is, setting the indium content of the second sub-section 142 to be smaller or setting the second sub-section 142 to contain no indium, the amount of indium used in the first conductive layer 131 can be reduced, and the cost of the first conductive layer 131 can be reduced.

[0120] Exemplarily, the material of the first sub-portion 141 includes indium compounds, for example, the material of the first sub-portion 141 includes indium tin oxide. Indium tin oxide has excellent conductivity and is beneficial to current transmission. In addition, indium tin oxide has high light transmittance and is beneficial to improving conversion efficiency.

[0121] Exemplarily, the material of the second sub-portion 142 includes at least one of an indium-free transparent conductive oxide and a transparent insulating material (eg, SiN), which can reduce the amount of indium in the first conductive layer 131 and thus reduce the cost of the first conductive layer 131 .

[0122] Exemplarily, the number of the first sub-section 141 is at least one, and when there are multiple first sub-sections 141, the multiple first sub-sections 141 are arranged at intervals. The embodiment of the present application is described by taking the case where there are multiple first sub-sections 141 as an example.

[0123] It can be understood that in other embodiments, the material of the first sub-portion 141 and the second sub-portion 142 may include at least one of indium tin oxide (ITO), aluminum zinc oxide (AZO), gallium aluminum zinc oxide (GAZO), tin oxide (SnO2), antimony tin oxide (ATO), fluorine tin oxide (FTO), cerium indium oxide (ICO), and aluminum indium oxide (IWO).

[0124] For example, see Figure 1, the solar cell 100 may have a first direction X, a second direction and a third direction Z, and the first direction X, the second direction and the third direction Z are all different. The first direction X, the second direction and the third direction Z may be perpendicular to each other. For example, the third direction Z may be the thickness direction of the semiconductor substrate 160, and the first direction X and the second direction may be any two different directions perpendicular to the thickness direction of the semiconductor substrate 160. The first direction X may be the width direction of the solar cell 100, and the second direction may be the length direction of the solar cell 100. The length, width and thickness in the embodiments of the present application are merely for the convenience of description and do not imply any limitation on the size. For example, the width may be greater than, equal to or less than the length. The direction of the solar cell 100 may be consistent with the direction of the film layer such as the semiconductor substrate 160.

[0125] In some embodiments, see Figure 5 The first doping layer 110 includes a plurality of first doping portions 110a arranged at intervals along the first direction X, and the plurality of first doping portions 110a are arranged correspondingly to the plurality of first sub-portions 141. The orthographic projection of the first sub-portion 141 on the semiconductor substrate 160 overlaps with the orthographic projection of the corresponding first doping portion 110a on the semiconductor substrate 160, so that the first sub-portion 141 and the corresponding first doping portion 110a are at least partially arranged opposite to each other in the thickness direction of the semiconductor substrate 160, so that the transmission path of the current between the first doping portion 110a and the corresponding first sub-portion 141 is shorter, which is beneficial to the transmission of the current.

[0126] Among them, in the embodiment of the present application, the corresponding arrangement of A and B may refer to: one A is corresponding to at least one B, or one B is corresponding to at least one A. The embodiment of the present application is described by taking the corresponding arrangement of one A and one B as an example. For example, the corresponding arrangement of multiple first doping portions 110a and multiple first sub-portions 141 may refer to: one first doping portion 110a and at least one first sub-portion 141 are correspondingly arranged, or one first sub-portion 141 is correspondingly arranged with at least one first doping portion 110a. The embodiment of the present application is described by taking the corresponding arrangement of one first sub-portion 141 and one first doping portion 110a as an example.

[0127] Exemplarily, the first doping portion 110 a may extend along the second direction.

[0128] Exemplarily, the first doped portion 110 a may be in a strip shape.

[0129] Exemplarily, the number of the first doping portions 110 a may range from 50 to 300. For example, the number of the first doping portions 110 a may range from 50 to 300. For example, the number of the first doping portions 110 a may range from 50, 100, 150, 200, 250, 300, or any value between 50 and 300.

[0130] For some examples, see Figure 6 The orthographic projection of the first sub-portion 141 on the semiconductor substrate 160 is located within the orthographic projection of the corresponding first doped portion 110a on the semiconductor substrate 160. In this way, the area of ​​the first sub-portion 141 is less than or equal to the area of ​​the first doped portion 110a. The first sub-portion 141 can be set smaller, which is beneficial to reducing the cost of the first conductive layer 131.

[0131] For other examples, see Figure 7 The orthographic projection of the first doped portion 110a on the semiconductor substrate 160 is located within the orthographic projection of the corresponding first sub-portion 141 on the semiconductor substrate 160, and part of the first sub-portion 141 covers the side wall of the first doped portion 110a. In this way, the first sub-portion 141 extends from the surface of the first doped portion 110a that is away from the semiconductor substrate 160 to the side wall of the first doped portion 110a, so that the first sub-portion 141 better wraps the first doped portion 110a, which can increase the contact area between the first sub-portion 141 and the first doped portion 110a, which is beneficial to increase the current transmission channel between the first sub-portion 141 and the first doped portion 110a, and is beneficial to current transmission. In addition, the first sub-portion 141 can completely separate the first doped portion 110a from the first electrode 181, which is beneficial to prevent the first electrode 181 from contacting the first doped portion 110a.

[0132] In some embodiments, see Figure 7 The solar cell 100 includes a plurality of first electrodes 181 arranged at intervals along a first direction X. The first electrodes 181 are located on a side of the first conductive layer 131 away from the semiconductor substrate 160. The first electrodes 181 can collect and transmit photogenerated carriers, thereby realizing the conversion of solar energy into electrical energy.

[0133] Exemplarily, the first electrode 181 may extend along the second direction.

[0134] Exemplarily, the first electrode 181 may be in a strip shape.

[0135] Exemplarily, the number of the first electrodes 181 may range from 50 to 100. For example, the number of the first electrodes 181 may range from 50 to 100. For example, the number of the first electrodes 181 may range from 50 to 100.

[0136] Exemplarily, multiple first electrodes 181 are arranged corresponding to multiple first sub-portions 141, and the orthographic projection of the first electrode 181 on the semiconductor substrate 160 is located within the orthographic projection of the corresponding first sub-portion 141 on the semiconductor substrate 160. In this way, the first electrode 181 and the corresponding first sub-portion 141 are relatively arranged in the thickness direction of the semiconductor substrate 160, so that the current transmission path between the first electrode 181 and the corresponding first sub-portion 141 is shorter, which is beneficial to the transmission of current. In addition, it is beneficial for the first sub-portion 141 to completely separate the first electrode 181 and the first doped portion 110a, thereby preventing the first electrode 181 from contacting the first doped portion 110a.

[0137] In some embodiments, see Figure 8 , the first doping portion 110a includes at least one first sub-doping portion 111 and at least one second sub-doping portion 112, and the first sub-doping portion 111 and the second sub-doping portion 112 are alternately arranged along the first direction X. The orthographic projection of the first electrode 181 on the semiconductor substrate 160 is located within the orthographic projection of the first sub-doping portion 111 on the semiconductor substrate 160, so that the first electrode 181 and the first sub-doping portion 111 are arranged opposite to each other along the thickness direction of the semiconductor substrate 160, and the current transmission is more affected by the first sub-doping portion 111. In addition, the orthographic projection of the first electrode 181 on the semiconductor substrate 160 does not overlap with the orthographic projection of the second sub-doping portion 112 on the semiconductor substrate 160, so that the first electrode 181 and the second sub-doping portion 112 are staggered along the thickness direction of the semiconductor substrate 160, and the current transmission is less affected by the second sub-doping portion 112.

[0138] In some embodiments, see Fig. 9 , the dimension of the first sub-doping portion 111 along the thickness direction of the semiconductor substrate 160 is smaller than the dimension of the second sub-doping portion 112 along the thickness direction of the semiconductor substrate 160, the thickness of the first sub-doping portion 111 is set to be small, and the current can pass through the first sub-doping portion 111 faster, which is beneficial to the transmission of the current. For example, the first doping portion 110a includes a plurality of second sub-doping portions 112, a first groove 1131 is formed between two adjacent second sub-doping portions 112, a first protrusion 1411 is provided on the side of the first sub-portion 141 facing the first doping portion 110a, and the first protrusion 1411 is inserted into the first groove 1131. By providing the first protrusion 1411 and the first groove 1131 that are embedded with each other, the contact area between the first sub-portion 141 and the first doping portion 110a can be increased, which is beneficial to increase the current transmission channel between the first sub-portion 141 and the first doping portion 110a, which is beneficial to current transmission. In addition, the connection stability between the first sub-portion 141 and the first doping portion 110a can also be improved.

[0139] In some embodiments, the crystallization rate of the first sub-doping portion 111 is greater than the crystallization rate of the second sub-doping portion 112 (the larger the crystallization rate, the better the conductivity). The crystallization rate of the first sub-doping portion 111, which has a greater impact on current transmission, is set to be larger, which is beneficial to improving the conductivity of the first sub-doping portion 111, thereby facilitating current transmission. The crystallization rate of the second sub-doping portion 112, which has a smaller impact on current transmission, is set to be smaller, which is beneficial to reducing the difficulty and cost of preparing the second sub-doping portion 112.

[0140] In some embodiments, the first sub-doping portion 111 and the second sub-doping portion 112 are both doped with oxygen (higher oxygen content means lower light absorption), and the oxygen content of the first sub-doping portion 111 is less than that of the second sub-doping portion 112. Since the first electrode 181 shields the first sub-doping portion 111 but does not shield the second sub-doping portion 112, more light will be irradiated to the second sub-doping portion 112, and the absorption of light by the second sub-doping portion 112 has a greater impact on the conversion efficiency, while the absorption of light by the first sub-doping portion 111 has a smaller impact on the conversion efficiency. Setting the oxygen content of the first sub-doping portion 111 shielded by the first electrode 181 to be lower is conducive to reducing the difficulty and cost of preparing the first sub-doping portion 111. In addition, setting the oxygen content of the second sub-doping portion 112 not shielded by the first electrode 181 to be higher is conducive to reducing the absorption of light by the second sub-doping portion 112 and improving the conversion efficiency.

[0141] Exemplarily, the size of the first electrode 181 along the first direction X is greater than or equal to 20 μm, so that the size of the first electrode 181 along the first direction X can be prevented from being too small, which is beneficial to improving the transmission of current by the first electrode 181. For example, the size of the first electrode 181 along the first direction X can be 20 μm, 30 μm, 40 μm, 50 μm, or any value greater than 20 μm.

[0142] Exemplarily, the size of the first doped portion 110a along the first direction X ranges from 0.385 mm to 5.775 mm, so that the size of the first doped portion 110a along the first direction X can be prevented from being too small, which is beneficial to the transmission of current. In addition, the size of the first doped portion 110a along the first direction X can be prevented from being too large, which is beneficial to reducing the coverage of the first doped layer 110, thereby facilitating the reduction of light absorption by the first doped layer 110. For example, the size of the first doped portion 110a along the first direction X can be 0.385 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 5.775 mm, or any value between 0.385 mm and 5.775 mm.

[0143] Exemplarily, the dimension of the first groove 1131 along the thickness direction of the semiconductor substrate 160 is less than or equal to 15 μm, so that the first groove 1131 can be prevented from being too deep, and the first doping layer 110 can be prevented from being too thick, which is beneficial to reduce the absorption of light by the first doping layer 110. For example, the dimension of the first groove 1131 along the thickness direction of the semiconductor substrate 160 can be 5 μm, 10 μm, 12 μm, 15 μm, or any value less than 15 μm.

[0144] Exemplarily, the size of the first groove 1131 along the first direction X is greater than or equal to 20 μm, so that the size of the first groove 1131 along the first direction X can be prevented from being too small, which is conducive to reducing the difficulty of the first protrusion 1411 extending into the first groove 1131, and is also conducive to increasing the contact area between the first doping part 110a and the first sub-part 141. For example, the size of the first groove 1131 along the first direction X can be 20 μm, 30 μm, 40 μm, 50 μm, or any value greater than 20 μm.

[0145] Exemplarily, in the same first doping portion 110a, the ratio of the sum of the projection areas of the orthographic projections of all the first sub-doping portions 111 on the semiconductor substrate 160 to the projection area of ​​the orthographic projection of the first doping portion 110a on the semiconductor substrate 160 is in the range of 78%-99%, thereby preventing the sum of the areas of all the first sub-doping portions 111 in the same first doping portion 110a from being too small, which is beneficial to current transmission. For example, the ratio may be 78%, 80%, 85%, 90%, 95%, 99%, or any value between 78% and 99%.

[0146] Exemplarily, the crystallization rate of the first sub-doping portion 111 is in the range of 40%-60%, so that the crystallization rate of the first sub-doping portion 111 can be prevented from being too low, which is beneficial to improving the conductivity of the first sub-doping portion 111. In addition, the crystallization rate of the first sub-doping portion 111 can be prevented from being too high, thereby reducing the difficulty and cost of preparing the first sub-doping portion 111. For example, the crystallization rate of the first sub-doping portion 111 can be 40%, 50%, 60%, or any value between 40% and 60%.

[0147] Exemplarily, the crystallization rate of the second sub-doping portion 112 is less than or equal to 40%, thereby preventing the crystallization rate of the second sub-doping portion 112 from being too high, which is beneficial to reducing the difficulty and cost of preparing the second sub-doping portion 112. For example, the crystallization rate of the second sub-doping portion 112 can be 20%, 30%, 40% or any value less than 40%.

[0148] Exemplarily, the difference between the crystallization rate of the first sub-doping portion 111 and the crystallization rate of the second sub-doping portion 112 is less than or equal to 60%. For example, the difference between the crystallization rate of the first sub-doping portion 111 and the crystallization rate of the second sub-doping portion 112 can be 10%, 20%, 30%, 40%, 50%, 60 or any value less than 60%.

[0149] Exemplarily, the oxygen content of the first sub-doping portion 111 is less than or equal to 2%, thereby preventing the oxygen content of the first sub-doping portion 111 from being too high, which is beneficial to reducing the difficulty and cost of preparing the first sub-doping portion 111. For example, the oxygen content of the first sub-doping portion 111 can be 0.5%, 1%, 1.5%, 2%, or any value less than 2%.

[0150] Exemplarily, the oxygen content of the second sub-doping portion 112 is in the range of 2%-5%, so that the oxygen content of the second sub-doping portion 112 can be prevented from being too low, which is beneficial to reducing the absorption of light by the second sub-doping portion 112. In addition, the oxygen content of the second sub-doping portion 112 can be prevented from being too high, which is beneficial to reducing the difficulty and cost of preparing the second sub-doping portion 112. For example, the oxygen content of the second sub-doping portion 112 can be 2%, 3%, 4%, 5%, or any value between 2% and 5%.

[0151] Exemplarily, the difference between the oxygen content of the second sub-doping portion 112 and the oxygen content of the first sub-doping portion 111 is less than or equal to 5%. For example, the difference between the oxygen content of the second sub-doping portion 112 and the oxygen content of the first sub-doping portion 111 can be 1%, 2%, 3%, 4%, 5%, or any value less than 5%.

[0152] It should be noted that the first conductive layer 131 may include a first sub-section 141 and a second sub-section 142 of different materials, and the first sub-section 141 and the second sub-section 142 may be prepared in steps. Alternatively, the first conductive layer 131 may also be an integral structure of the entire layer, and the first sub-section 141 and the second sub-section 142 may also be integrally formed.

[0153] See also Fig.12 In some embodiments, the orthographic projection of the first surface 161 on the semiconductor substrate 160 is located within the orthographic projection of the first conductive layer 131 on the semiconductor substrate 160, and part of the first conductive layer 131 covers the side wall of the semiconductor substrate 160, that is, the first conductive layer 131 completely covers the first surface 161 and extends from the first surface 161 to the side wall of the semiconductor substrate 160, so that the first conductive layer 131 has a wider coverage area, which is beneficial to the transmission of current. In addition, the side wall of the semiconductor substrate 160 can also be protected.

[0154] The second doping layer 120 and the second conductive layer 132 provided in the embodiment of the present application are further described below.

[0155] In some embodiments, see Figure 3 There is a spacing (i.e., a second spacing D2) between the orthographic projection of the second doped layer 120 on the semiconductor substrate 160 and the outer contour of the orthographic projection of the second surface 162 on the semiconductor substrate 160, thereby reducing the setting area of ​​the second doped layer 120. In addition, a spacing is provided between the second doped layer 120 and the side wall of the semiconductor substrate 160, which is beneficial to preventing the second doped layer 120 from being formed on the side wall of the semiconductor substrate 160, thereby preventing a parasitic PN junction diode from being formed on the side wall of the semiconductor substrate 160, thereby fundamentally preventing leakage caused by the parasitic PN junction diode.

[0156] In this embodiment of the present application, at least one of the first spacing D1 and the second spacing D2 may be set. The embodiment of the present application is described by taking the first spacing D1 and the second spacing D2 as an example. The first spacing D1 and the second spacing D2 may be the same, or may be different.

[0157] For example, the second distance D2 may be less than or equal to 5 mm, thereby preventing the second distance D2 from being too large, which is beneficial to improving the flexibility of setting the second doping layer 120. For example, the second distance D2 may be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, or any value less than 5 mm.

[0158] Exemplarily, the ratio of the projection area of ​​the orthographic projection of the second doped layer 120 on the semiconductor substrate 160 to the projection area of ​​the orthographic projection of the second surface 162 on the semiconductor substrate 160 is β, and β is ≥ 55%, thereby preventing the area of ​​the second doped layer 120 from being too small, which is beneficial to current transmission. For example, β can be 55%, 60%, 80%, 90%, or any value greater than 55%.

[0159] In some embodiments, see Figure 3 The solar cell 100 includes a second conductive layer 132, which is disposed on a side of the second doping layer 120 away from the semiconductor substrate 160. The second conductive layer 132 can collect the current generated by the battery and transmit it to the second electrode 182. In addition, the second conductive layer 132 can also have an anti-reflection effect.

[0160] Exemplarily, the conductivity of the second conductive layer 132 is greater than the conductivity of the second doping layer 120 , thereby facilitating the collection and transmission of current.

[0161] Exemplarily, the light transmittance of the second conductive layer 132 is greater than the light transmittance of the second doping layer 120 , which is beneficial for light transmission and improves the conversion efficiency of the solar cell 100 .

[0162] In some embodiments, see Figure 5 The second conductive layer 132 includes a third sub-portion 143 and a fourth sub-portion 144. The orthographic projection of the third sub-portion 143 on the semiconductor substrate 160 overlaps with the orthographic projection of the second doped layer 120 on the semiconductor substrate 160. In this way, the third sub-portion 143 and the second doped layer 120 are at least partially arranged opposite to each other in the thickness direction of the semiconductor substrate 160, so that the transmission path of the current between the second doped layer 120 and the third sub-portion 143 is short, which is conducive to the transmission of the current. In addition, the orthographic projection of at least part of the fourth sub-portion 144 on the semiconductor substrate 160 does not overlap with the orthographic projection of the second doped layer 120 on the semiconductor substrate 160. In this way, the fourth sub-portion 144 and the second doped layer 120 are at least partially staggered in the thickness direction of the semiconductor substrate 160, so that the fourth sub-portion 144 has a small influence on the current collection ability of the second conductive layer 132. When the fourth sub-portion 144 is arranged, the material of the fourth sub-portion 144 can be set to a conductive or non-conductive material, so that the material selection range of the fourth sub-portion 144 can be expanded.

[0163] Exemplarily, the third sub-section 143 and the fourth sub-section 144 may both have an anti-reflection effect.

[0164] Exemplarily, the conductivity of the third sub-portion 143 is greater than the conductivity of the fourth sub-portion 144 , and the conductivity of the third sub-portion 143 is set to be relatively large, thereby facilitating current transmission.

[0165] Exemplarily, the material of the third sub-portion 143 is different from the material of the fourth sub-portion 144. For example, the material of the third sub-portion 143 includes indium, and the indium content of the third sub-portion 143 is greater than the indium content of the fourth sub-portion 144, that is, the indium content of the fourth sub-portion 144 is set to be smaller or the fourth sub-portion 144 is set to contain no indium, so as to reduce the amount of indium in the second conductive layer 132, thereby reducing the cost of the second conductive layer 132.

[0166] Exemplarily, the material of the third sub-section 143 includes indium compounds, for example, the material of the third sub-section 143 includes indium tin oxide. Indium tin oxide has excellent conductivity and is beneficial to current transmission. In addition, indium tin oxide has high light transmittance and is beneficial to improving conversion efficiency.

[0167] Exemplarily, the material of the fourth sub-portion 144 includes at least one of an indium-free transparent conductive oxide and a transparent insulating material (eg, SiN), which can reduce the amount of indium in the second conductive layer 132 and thus reduce the cost of the second conductive layer 132 .

[0168] Exemplarily, the number of the third sub-section 143 is at least one, and when there are multiple third sub-sections 143, the multiple third sub-sections 143 are arranged at intervals. The embodiment of the present application is described by taking multiple third sub-sections 143 as an example.

[0169] It can be understood that, in other embodiments, the material of the third sub-portion 143 and the fourth sub-portion 144 may include at least one of indium tin oxide (ITO), aluminum zinc oxide (AZO), gallium aluminum zinc oxide (GAZO), tin oxide (SnO2), antimony tin oxide (ATO), fluorine tin oxide (FTO), cerium indium oxide (ICO), and aluminum indium oxide (IWO).

[0170] In some embodiments, see Figure 5 The second doping layer 120 includes a plurality of second doping portions 120a arranged at intervals along the first direction X, the plurality of second doping portions 120a are arranged corresponding to the plurality of third sub-portions 143, and the orthographic projection of the third sub-portion 143 on the semiconductor substrate 160 overlaps with the orthographic projection of the corresponding second doping portion 120a on the semiconductor substrate 160. In this way, the third sub-portion 143 and the corresponding second doping portion 120a are at least partially arranged opposite to each other in the thickness direction of the semiconductor substrate 160, so that the transmission path of the current between the second doping portion 120a and the corresponding third sub-portion 143 is shorter, which is beneficial to the transmission of the current.

[0171] Exemplarily, the second doping portion 120 a may extend along the second direction.

[0172] Exemplarily, the second doped portion 120 a may be in a strip shape.

[0173] Exemplarily, the number of the second doping portions 120 a may range from 50 to 300. For example, the number of the second doping portions 120 a may range from 50 to 300. For example, the number of the second doping portions 120 a may range from 50, 100, 150, 200, 250, 300, or any value between 50 and 300.

[0174] In some examples, the orthographic projection of the third sub-portion 143 on the semiconductor substrate 160 is located within the orthographic projection of the corresponding second doped portion 120a on the semiconductor substrate 160. In this way, the area of ​​the third sub-portion 143 is less than or equal to the area of ​​the second doped portion 120a. The third sub-portion 143 can be set to be smaller, which is beneficial to reducing the cost of the second conductive layer 132.

[0175] In other examples, the orthographic projection of the second doped portion 120a on the semiconductor substrate 160 is located within the orthographic projection of the corresponding third sub-portion 143 on the semiconductor substrate 160, and part of the third sub-portion 143 covers the side wall of the second doped portion 120a. In this way, the third sub-portion 143 extends from the surface of the second doped portion 120a facing away from the semiconductor substrate 160 to the side wall of the second doped portion 120a, which is beneficial to current transmission. In addition, it is also beneficial to prevent the second electrode 182 from contacting the second doped portion 120a. The principle has been explained and will not be repeated here.

[0176] In some embodiments, see Figure 5The solar cell 100 includes a plurality of second electrodes 182 arranged at intervals along the first direction X. The second electrodes 182 are located on a side of the second conductive layer 132 away from the semiconductor substrate 160. The second electrodes 182 can collect and transmit photogenerated carriers, thereby realizing the conversion of solar energy into electrical energy.

[0177] Exemplarily, the second electrode 182 may extend along the second direction.

[0178] Exemplarily, the second electrode 182 may be in a strip shape.

[0179] Exemplarily, the number of the second electrodes 182 may range from 50 to 100. For example, the number of the second electrodes 182 may range from 50 to 100. For example, the number of the second electrodes 182 may range from 50 to 100.

[0180] For example, see Figure 5 , multiple second electrodes 182 are arranged corresponding to multiple third sub-portions 143, and the orthographic projection of the second electrode 182 on the semiconductor substrate 160 is located within the orthographic projection of the corresponding third sub-portion 143 on the semiconductor substrate 160. In this way, the second electrode 182 and the corresponding third sub-portion 143 are relatively arranged in the thickness direction of the semiconductor substrate 160, so that the current transmission path between the second electrode 182 and the corresponding third sub-portion 143 is shorter, which is beneficial to the transmission of current.

[0181] In some embodiments, see Fig.10 , the second doping portion 120a includes at least one third sub-doping portion 123 and at least one fourth sub-doping portion 124, and the third sub-doping portion 123 and the fourth sub-doping portion 124 are alternately arranged along the first direction X. The orthographic projection of the second electrode 182 on the semiconductor substrate 160 is located within the orthographic projection of the third sub-doping portion 123 on the semiconductor substrate 160, so that the second electrode 182 and the third sub-doping portion 123 are arranged opposite to each other along the thickness direction of the semiconductor substrate 160, and the current transmission is more affected by the third sub-doping portion 123. In addition, the orthographic projection of the second electrode 182 on the semiconductor substrate 160 does not overlap with the orthographic projection of the fourth sub-doping portion 124 on the semiconductor substrate 160, so that the second electrode 182 and the fourth sub-doping portion 124 are staggered along the thickness direction of the semiconductor substrate 160, and the current transmission is less affected by the fourth sub-doping portion 124.

[0182] In some embodiments, see Fig.11, the dimension of the third sub-doping portion 123 along the thickness direction of the semiconductor substrate 160 is smaller than the dimension of the fourth sub-doping portion 124 along the thickness direction of the semiconductor substrate 160, the thickness of the third sub-doping portion 123 is set to be small, and the current can pass through the third sub-doping portion 123 faster, which is beneficial to the transmission of the current. For example, the second doping portion 120a includes a plurality of fourth sub-doping portions 124, a second groove 1252 is formed between two adjacent fourth sub-doping portions 124, and a second protrusion 1432 is provided on the side of the third sub-portion 143 facing the second doping portion 120a, and the second protrusion 1432 is embedded in the second groove 1252, which is beneficial to the transmission of the current. In addition, the connection stability between the third sub-portion 143 and the second doping portion 120a can also be improved. The principle has been explained and will not be repeated.

[0183] In some embodiments, the crystallization rate of the third sub-doping portion 123 is greater than that of the fourth sub-doping portion 124 , which is beneficial to the transmission of current and also helps to reduce the difficulty and cost of preparing the fourth sub-doping portion 124 . The principle has been explained and will not be repeated here.

[0184] In some embodiments, the third sub-doping part 123 and the fourth sub-doping part 124 are both doped with oxygen, and the oxygen content of the third sub-doping part 123 is less than that of the fourth sub-doping part 124, which is conducive to reducing the difficulty and cost of preparing the third sub-doping part 123. In addition, it is conducive to reducing the absorption of light by the fourth sub-doping part 124, which is conducive to improving the conversion efficiency. The principle has been explained and will not be repeated here.

[0185] Exemplarily, the size of the second electrode 182 along the first direction X is greater than or equal to 20 μm, so that the size of the second electrode 182 along the first direction X can be prevented from being too small, which is beneficial to improving the transmission of current by the second electrode 182. For example, the size of the second electrode 182 along the first direction X can be 20 μm, 30 μm, 40 μm, 50 μm, or any value greater than 20 μm.

[0186] Exemplarily, the size of the second doped portion 120a along the first direction X ranges from 0.385 mm to 5.775 mm, so that the size of the second doped portion 120a along the first direction X can be prevented from being too small, which is beneficial to the transmission of current. In addition, the size of the second doped portion 120a along the first direction X can be prevented from being too large, which is beneficial to reducing the coverage of the second doped layer 120 and reducing the absorption of light by the second doped layer 120. For example, the size of the second doped portion 120a along the first direction X can be 0.385 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 5.775 mm, or any value between 0.385 mm and 5.775 mm.

[0187] Exemplarily, the dimension of the second groove 1252 along the thickness direction of the semiconductor substrate 160 is less than or equal to 15 μm, so that the second groove 1252 can be prevented from being too deep, and the second doping layer 120 can be prevented from being too thick, which is beneficial to reduce the absorption of light by the second doping layer 120. For example, the dimension of the second groove 1252 along the thickness direction of the semiconductor substrate 160 can be 5 μm, 10 μm, 12 μm, 15 μm, or any value less than 15 μm.

[0188] Exemplarily, the size of the second groove 1252 along the first direction X is greater than or equal to 20 μm, so that the size of the second groove 1252 along the first direction X can be prevented from being too small, which is conducive to reducing the difficulty of the second protrusion 1432 extending into the second groove 1252, and is also conducive to increasing the contact area between the second doping part 120a and the third sub-part 143. For example, the size of the second groove 1252 along the first direction X can be 20 μm, 30 μm, 40 μm, 50 μm or any value greater than 20 μm.

[0189] Exemplarily, in the same second doping portion 120a, the ratio of the sum of the projection areas of the orthographic projections of all the third sub-doping portions 123 on the semiconductor substrate 160 to the projection area of ​​the orthographic projections of the second doping portion 120a on the semiconductor substrate 160 is in the range of 78%-99%, thereby preventing the sum of the areas of all the third sub-doping portions 123 in the same second doping portion 120a from being too small, which is beneficial to current transmission. For example, the ratio may be 78%, 80%, 85%, 90%, 95%, 99%, or any value between 78% and 99%.

[0190] Exemplarily, the crystallization rate of the third sub-doping portion 123 is in the range of 40%-60%, so that the crystallization rate of the third sub-doping portion 123 can be prevented from being too low, which is beneficial to improving the conductivity of the third sub-doping portion 123. In addition, the crystallization rate of the third sub-doping portion 123 can be prevented from being too high, thereby reducing the difficulty and cost of preparing the third sub-doping portion 123. For example, the crystallization rate of the third sub-doping portion 123 can be 40%, 50%, 60%, or any value between 40% and 60%.

[0191] Exemplarily, the crystallization rate of the fourth sub-doping portion 124 is less than or equal to 40%, so that the crystallization rate of the fourth sub-doping portion 124 can be prevented from being too high, which is beneficial to the difficulty and cost of preparing the fourth sub-doping portion 124. For example, the crystallization rate of the fourth sub-doping portion 124 can be 20%, 30%, 40% or any value less than 40%.

[0192] Exemplarily, the difference between the crystallization rate of the third sub-doping portion 123 and the crystallization rate of the fourth sub-doping portion 124 is less than or equal to 60%. For example, the difference between the crystallization rate of the third sub-doping portion 123 and the crystallization rate of the fourth sub-doping portion 124 can be 10%, 20%, 30%, 40%, 50%, 60 or any value less than 60%.

[0193] Exemplarily, the oxygen content of the third sub-doping portion 123 is less than or equal to 2%, thereby preventing the third sub-doping portion 123 from having an excessively high oxygen content, which is beneficial for reducing the difficulty and cost of preparing the third sub-doping portion 123. For example, the oxygen content of the third sub-doping portion 123 may be 0.5%, 1%, 1.5%, 2%, or any value less than 2%.

[0194] Exemplarily, the oxygen content of the fourth sub-doping portion 124 is in the range of 2%-5%, so that the oxygen content of the fourth sub-doping portion 124 can be prevented from being too low, which is beneficial to reducing the absorption of light by the fourth sub-doping portion 124. In addition, the oxygen content of the fourth sub-doping portion 124 can be prevented from being too high, which is beneficial to reducing the difficulty and cost of preparing the fourth sub-doping portion 124. For example, the oxygen content of the fourth sub-doping portion 124 can be 2%, 3%, 4%, 5%, or any value between 2% and 5%.

[0195] Exemplarily, the difference between the oxygen content of the fourth sub-doping portion 124 and the oxygen content of the third sub-doping portion 123 is less than or equal to 5%. For example, the difference between the oxygen content of the fourth sub-doping portion 124 and the oxygen content of the third sub-doping portion 123 can be 1%, 2%, 3%, 4%, 5%, or any value less than 5%.

[0196] It should be noted that the second conductive layer 132 may include a third sub-portion 143 and a fourth sub-portion 144 of different materials, and the third sub-portion 143 and the fourth sub-portion 144 may be prepared in steps, or the second conductive layer 132 may be an integral structure of the entire layer, and the third sub-portion 143 and the fourth sub-portion 144 may be integrally formed.

[0197] In some embodiments, see Fig.12 There is an indirect distance (i.e., a third distance D3) between the orthographic projection of the second conductive layer 132 on the semiconductor substrate 160 and the outer contour of the orthographic projection of the second surface 162 on the semiconductor substrate 160, so that there is a distance between the second conductive layer 132 and the side wall of the semiconductor substrate 160, which is beneficial to prevent the second conductive layer 132 from being formed on the side wall of the semiconductor substrate 160, thereby avoiding contact between the first conductive layer 131 and the second conductive layer 132, which is beneficial to prevent leakage.

[0198] Exemplarily, the third distance D3 is less than or equal to 5 mm, so as to avoid the third distance D3 being too large, which is beneficial to the transmission of current. For example, the third distance D3 can be 1 mm, 2 mm, 3 mm, 5 mm or any value less than 5 mm.

[0199] The first intrinsic semiconductor layer 171 and the second intrinsic semiconductor layer 172 provided in the embodiment of the present application are described below.

[0200] In some embodiments, see Figure 1 The solar cell 100 may include a first intrinsic semiconductor layer 171, which is disposed on the first surface 161. The first intrinsic semiconductor layer 171 is disposed between the semiconductor substrate 160 and the first doped layer 110. The first intrinsic semiconductor layer 171 may play a passivation role, which may improve the photoelectric conversion efficiency by reducing the surface recombination rate, and may also protect the solar cell 100 from the erosion of the external environment and enhance the stability of the solar cell 100.

[0201] In some embodiments, see Figure 1 The solar cell 100 includes a second intrinsic semiconductor layer 172, which is disposed on the second surface 162. The second intrinsic semiconductor layer 172 is disposed between the semiconductor substrate 160 and the second doping layer 120. The second intrinsic semiconductor layer 172 can play a passivation role, which can improve the photoelectric conversion efficiency by reducing the surface recombination rate, and can also protect the solar cell 100 from erosion by the external environment and enhance the stability of the solar cell 100.

[0202] Exemplarily, at least one of the first intrinsic semiconductor layer 171 and the second intrinsic semiconductor layer 172 has a thickness ranging from 1 nm to 5 nm. For example, the thickness may be 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, or any value between 1 nm and 5 nm.

[0203] The photovoltaic module provided in the embodiments of the present application is described below.

[0204] The embodiment of the present application further provides a photovoltaic module, which may include the solar cell 100 in the above embodiment. There may be at least one solar cell 100 in the photovoltaic module. The embodiment of the present application is described by taking the case where there are multiple solar cells 100 in the photovoltaic module as an example, and the multiple solar cells 100 together constitute a battery string layer.

[0205] In some embodiments, the photovoltaic module may include a first encapsulation member and a second encapsulation member located on both sides of the battery string layer, and the first encapsulation member and the second encapsulation member encapsulate the battery string layer to protect the battery string layer. The first encapsulation member and the second encapsulation member may include an encapsulation adhesive layer and a cover plate, the encapsulation adhesive layer is located on the side of the cover plate facing the battery string layer, the cover plate can protect the battery string layer, and the encapsulation adhesive layer can be used to connect the cover plate and the battery string layer.

[0206] The following is an explanation of a method for preparing the solar cell 100 provided in an embodiment of the present application.

[0207] The present application embodiment provides a method for preparing a solar cell 100, which can be used to prepare the solar cell 100 in the above embodiment. The preparation method may include:

[0208] First, a semiconductor substrate 160 is provided. The semiconductor substrate 160 has a first surface 161 and a second surface 162 that are opposite to each other.

[0209] Exemplarily, at least one of the first surface 161 and the second surface 162 of the semiconductor substrate 160 may be textured so that at least one of the first surface 161 and the second surface 162 forms a texture structure.

[0210] For example, the velvet structure can be prepared by wet chemical etching, for example, an alkaline solution can be used for velvet preparation, such as a NaOH solution, or chemical etching, laser etching, mechanical method, plasma etching, etc. can be used to prepare the velvet structure.

[0211] In some embodiments, see Figure 1 After providing the semiconductor substrate 160 , the method may include depositing a first intrinsic semiconductor layer 171 on the first surface 161 and depositing a second intrinsic semiconductor layer 172 on the second surface 162 .

[0212] Exemplarily, the deposition process may include atomic layer deposition (ALD), physical vapor deposition (PVD), chemical vapor deposition (CVD), or reactive plasma deposition (RPD). Other structural layers in the embodiments of the present disclosure may also be formed by deposition, which will not be described in detail.

[0213] For example, the first intrinsic semiconductor layer 171 and the second intrinsic semiconductor layer 172 may be formed by using a radio frequency enhanced plasma chemical vapor deposition (RF-PECVD) process.

[0214] Exemplarily, the deposition temperature of the first intrinsic semiconductor layer 171 and the second intrinsic semiconductor layer 172 ranges from 100° C. to 300° C.

[0215] In some embodiments, after forming the first intrinsic semiconductor layer 171 and the second intrinsic semiconductor layer 172, it can include forming a first doping material layer on a side of the first intrinsic semiconductor layer 171 away from the semiconductor substrate 160, performing a first patterning process on the first doping material layer to form a first doping layer 110, forming a second doping material layer on a side of the second intrinsic semiconductor layer 172 away from the semiconductor substrate 160, and performing a second patterning process on the second doping material layer to form a second doping layer 120. Specifically, a photoresist layer can be formed by spin coating, the photoresist layer covers the first intrinsic semiconductor layer 171, the second intrinsic semiconductor layer 172 and the sidewalls of the semiconductor substrate 160, and the photoresist layer is subjected to a third patterning process, a portion of the photoresist layer corresponding to the first doped layer 110 is removed to form a first hollow portion corresponding to the first doped layer 110 on the photoresist layer of the first surface 161, a portion of the photoresist layer corresponding to the second doped layer 120 is removed to form a second hollow portion corresponding to the second doped layer 120 on the photoresist layer of the second surface 162, and then a first doped layer 110 is formed on the photoresist layer of the first surface 161. A material layer is formed on the photoresist layer on the second surface 162 and the first doping material layer fills the first hollow portion, a second doping material layer is formed on the photoresist layer on the second surface 162 and the second doping material layer fills the second hollow portion, and then the sample is immersed in a solvent (for example, acetone, toluene or propanol, etc.) to remove the remaining photoresist layer, remove the first doping material layer on the photoresist layer on the first surface 161, and remove the second doping material layer on the photoresist layer on the second surface 162, retain the first doping material layer in the first hollow portion and form a first doping layer 110, retain the second doping material layer in the second hollow portion and form a second doping layer 120.

[0216] For example, the first doping layer 110 and the second doping layer 120 may be formed by a plasma enhanced chemical vapor deposition (PECVD) process.

[0217] Exemplarily, the deposition temperature of the first doping layer 110 and the second doping layer 120 ranges from 100° C. to 300° C.

[0218] Among them, in the embodiments of the present application, the patterning process can be carried out by chemical solution etching, laser film opening, or photolithography, development and exposure.

[0219] After forming the first doping layer 110 , the process may include forming a first conductive layer 131 on a side of the first doping layer 110 facing away from the semiconductor substrate 160 .

[0220] After forming the second doping layer 120 , the process may include forming a second conductive layer 132 on a side of the second doping layer 120 facing away from the semiconductor substrate 160 .

[0221] Exemplarily, the first conductive layer 131 and the second conductive layer 132 may be formed by magnetron sputtering, reactive plasma deposition, electron beam evaporation, or the like.

[0222] Exemplarily, the thickness of the first conductive layer 131 and the second conductive layer 132 may be in the range of 10 nm to 100 nm.

[0223] Exemplarily, the preparation temperature of the first conductive layer 131 and the second conductive layer 132 may be in the range of 25° C. to 300° C.

[0224] After forming the first conductive layer 131 and the second conductive layer 132 , a first electrode 181 may be formed on a side of the first conductive layer 131 facing away from the semiconductor substrate 160 , and a second electrode may be formed on a side of the second conductive layer 132 facing away from the semiconductor substrate 160 , so as to form the solar cell 100 .

[0225] For example, the first electrode 181 and the second electrode 182 may be formed by screen printing, drying and sintering.

[0226] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0227] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A solar cell, characterized in that: include: A semiconductor substrate having a first surface and a second surface arranged opposite to each other; A first intrinsic semiconductor layer, disposed on the first surface; A first doping layer is disposed on a side of the first intrinsic semiconductor layer away from the semiconductor substrate; The projection area of ​​the orthographic projection of the first doped layer on the semiconductor substrate is smaller than the projection area of ​​the orthographic projection of the first surface on the semiconductor substrate.

2. The solar cell according to claim 1, characterized in that An orthographic projection of the first doped layer on the semiconductor substrate has a first distance from an outer contour of an orthographic projection of the first surface on the semiconductor substrate.

3. The solar cell according to claim 2, characterized in that: The first spacing is less than or equal to 5 mm.

4. The solar cell according to any one of claims 1 to 3, characterized in that: The ratio of the projection area of ​​the orthographic projection of the first doped layer on the semiconductor substrate to the projection area of ​​the orthographic projection of the first surface on the semiconductor substrate is α, and α satisfies the condition: α≥55%。 5. The solar cell according to any one of claims 1 to 3, characterized in that: The solar cell comprises a first conductive layer, wherein the first conductive layer is arranged on a side of the first doped layer away from the semiconductor substrate; The first conductive layer includes a first sub-portion and a second sub-portion, and an orthographic projection of the first sub-portion on the semiconductor substrate overlaps with an orthographic projection of the first doped layer on the semiconductor substrate; An orthographic projection of at least a portion of the second sub-portion on the semiconductor substrate does not overlap with an orthographic projection of the first doped layer on the semiconductor substrate.

6. The solar cell according to claim 5, characterized in that: The conductivity of the first conductive layer is greater than the conductivity of the first doped layer; and / or, The light transmittance of the first conductive layer is greater than the light transmittance of the first doping layer.

7. The solar cell according to claim 5, characterized in that: The conductivity of the first sub-section is greater than the conductivity of the second sub-section; and / or, The material of the first sub-portion includes indium compound.

8. The solar cell according to claim 5, characterized in that: The material of the first sub-section includes indium tin oxide; The material of the second sub-portion includes at least one of an indium-free transparent conductive oxide and a transparent insulating material.

9. The solar cell according to claim 5, characterized in that: The first doping layer includes a plurality of first doping portions arranged at intervals along a first direction, wherein the first direction is perpendicular to a thickness direction of the semiconductor substrate; There are a plurality of the first sub-sections, and the plurality of the first doped sections are arranged correspondingly to the plurality of the first sub-sections; An orthographic projection of the first sub-portion on the semiconductor substrate overlaps with an orthographic projection of the corresponding first doped portion on the semiconductor substrate.

10. The solar cell according to claim 9, characterized in that: The orthographic projection of the first sub-portion on the semiconductor substrate is located within the orthographic projection of the corresponding first doped portion on the semiconductor substrate; Alternatively, an orthographic projection of the first doped portion on the semiconductor substrate is located within an orthographic projection of a corresponding first sub-portion on the semiconductor substrate, and a portion of the first sub-portion covers a side wall of the first doped portion.

11. The solar cell according to claim 9, characterized in that: The solar cell comprises a plurality of first electrodes arranged at intervals along the first direction, wherein the first electrodes are located on a side of the first conductive layer away from the semiconductor substrate; The plurality of first electrodes are arranged corresponding to the plurality of first sub-portions, and the orthographic projections of the first electrodes on the semiconductor substrate are located within the orthographic projections of the corresponding first sub-portions on the semiconductor substrate.

12. The solar cell according to claim 11, characterized in that: The first doping portion includes at least one first sub-doping portion and at least one second sub-doping portion, and the first sub-doping portions and the second sub-doping portions are alternately arranged along the first direction; The orthographic projection of the first electrode on the semiconductor substrate is located within the orthographic projection of the first sub-doped portion on the semiconductor substrate, and does not overlap with the orthographic projection of the second sub-doped portion on the semiconductor substrate.

13. The solar cell according to claim 12, characterized in that: The first doping portion includes a plurality of the second sub-doping portions; The dimension of the first sub-doping portion along the thickness direction of the semiconductor substrate is smaller than the dimension of the second sub-doping portion along the thickness direction of the semiconductor substrate, and a first groove is formed between two adjacent second sub-doping portions; A first protrusion is disposed on a side of the first sub-portion facing the first doping portion, and the first protrusion is engaged with the first groove.

14. The solar cell according to claim 12, characterized in that: A crystallization rate of the first sub-doping portion is greater than a crystallization rate of the second sub-doping portion.

15. The solar cell according to claim 12, characterized in that: The first sub-doping portion and the second sub-doping portion are both doped with oxygen, and the oxygen content of the first sub-doping portion is less than the oxygen content of the second sub-doping portion.

16. The solar cell according to claim 11, characterized in that: The size of the first electrode along the first direction is greater than or equal to 20 μm; and / or, A size of the first doped portion along the first direction ranges from 0.385 mm to 5.775 mm.

17. The solar cell according to claim 13, characterized in that: The dimension of the first groove along the thickness direction of the semiconductor substrate is less than or equal to 15 μm; and / or, A dimension of the first groove along the first direction is greater than or equal to 20 μm.

18. The solar cell according to claim 12, characterized in that: In the same first doping portion, a ratio of a sum of projection areas of orthographic projections of all the first sub-doping portions on the semiconductor substrate to a projection area of ​​an orthographic projection of the first doping portion on the semiconductor substrate is in a range of 78%-99%.

19. The solar cell according to claim 12, characterized in that: The crystallization rate of the first sub-doped portion is in the range of 40%-60%; and / or, The crystallization rate of the second sub-doping portion is less than or equal to 40%; and / or, The difference between the crystallization rate of the first sub-doping portion and the crystallization rate of the second sub-doping portion is less than or equal to 60%; and / or, The oxygen content of the first sub-doping portion is less than or equal to 2%; and / or, The oxygen content of the second sub-doping portion is in the range of 2%-5%; and / or, The difference between the oxygen content of the second sub-doping portion and the oxygen content of the first sub-doping portion is less than or equal to 5%.

20. The solar cell according to claim 5, characterized in that The orthographic projection of the first surface on the semiconductor substrate is located within the orthographic projection of the first conductive layer on the semiconductor substrate, and a portion of the first conductive layer covers the side wall of the semiconductor substrate.

21. The solar cell according to any one of claims 1 to 3, characterized in that: The solar cell comprises a second intrinsic semiconductor layer and a second doped layer, wherein the second intrinsic semiconductor layer is arranged on the second surface, and the second doped layer is arranged on a side of the second intrinsic semiconductor layer away from the semiconductor substrate; A projection area of ​​an orthographic projection of the second doped layer on the semiconductor substrate is smaller than a projection area of ​​an orthographic projection of the second surface on the semiconductor substrate.

22. The solar cell according to claim 21, characterized in that There is a second distance between the orthographic projection of the second doped layer on the semiconductor substrate and the outer contour of the orthographic projection of the second surface on the semiconductor substrate.

23. The solar cell according to claim 22, characterized in that The second spacing is less than or equal to 5 mm.

24. The solar cell according to claim 21, characterized in that The solar cell comprises a second conductive layer, the second conductive layer is arranged on a side of the second doped layer away from the semiconductor substrate, and the second conductive layer comprises a third sub-portion and a fourth sub-portion; The orthographic projection of the third sub-portion on the semiconductor substrate overlaps with the orthographic projection of the second doped layer on the semiconductor substrate, and the orthographic projection of at least part of the fourth sub-portion on the semiconductor substrate does not overlap with the orthographic projection of the second doped layer on the semiconductor substrate.

25. The solar cell according to claim 24, characterized in that The second doping layer includes a plurality of second doping portions arranged at intervals along a first direction, wherein the first direction is perpendicular to a thickness direction of the semiconductor substrate; There are multiple third sub-sections, and the multiple second doped sections are arranged corresponding to the multiple third sub-sections. The orthographic projection of the third sub-section on the semiconductor substrate overlaps with the orthographic projection of the corresponding second doped section on the semiconductor substrate.

26. The solar cell according to claim 25, characterized in that The solar cell comprises a plurality of second electrodes arranged at intervals along the first direction, wherein the second electrodes are located on a side of the second conductive layer away from the semiconductor substrate; The plurality of second electrodes are arranged corresponding to the plurality of third sub-portions, and the orthographic projections of the second electrodes on the semiconductor substrate are located within the orthographic projections of the corresponding third sub-portions on the semiconductor substrate.

27. The solar cell according to claim 26, characterized in that The second doping portion includes at least one third sub-doping portion and at least one fourth sub-doping portion, and the third sub-doping portion and the fourth sub-doping portion are alternately arranged along the first direction; The orthographic projection of the second electrode on the semiconductor substrate is located within the orthographic projection of the third sub-doped portion on the semiconductor substrate, and does not overlap with the orthographic projection of the fourth sub-doped portion on the semiconductor substrate.

28. The solar cell according to claim 27, characterized in that The second doping portion includes a plurality of the fourth sub-doping portions, the dimension of the third sub-doping portion along the thickness direction of the semiconductor substrate is smaller than the dimension of the fourth sub-doping portion along the thickness direction of the semiconductor substrate, a second groove is formed between two adjacent fourth sub-doping portions, a second protrusion is provided on a side of the third sub-portion facing the second doping portion, and the second protrusion is engaged with the second groove; and / or, The crystallization rate of the third sub-doping portion is greater than the crystallization rate of the fourth sub-doping portion; and / or, The third sub-doping portion and the fourth sub-doping portion are both doped with oxygen, and the oxygen content of the third sub-doping portion is less than the oxygen content of the fourth sub-doping portion.

29. The solar cell according to claim 24, characterized in that A third distance exists between the orthographic projection of the second conductive layer on the semiconductor substrate and the outer contour of the orthographic projection of the second surface on the semiconductor substrate.

30. The solar cell according to claim 29, characterized in that The third spacing is less than or equal to 5 mm.

31. A photovoltaic module, characterized in that: A solar cell comprising any one of claims 1 to 30.

Images