Solar cell and photovoltaic module

Abstract

The embodiment of the invention relates to the photovoltaic field, and provides a solar cell piece and a photovoltaic module, and the solar cell piece comprises a substrate which comprises a front surface and a back surface which are opposite to each other, and the substrate comprises metal regions and non-metal regions which are alternately arranged; the tunneling oxide layer at least covers the non-metal region on the front side; the first doped conductive layer is located on the metal region on the front side, the first doped conductive layer is doped with a first doped element and a second doped element, the first doped element is a metal element, and the second doped element is a non-metal element; the second doped conductive layer is located on the surface of the tunneling oxide layer and the surface of the first doped conductive layer, and the second doped conductive layer is doped with a first doping element; the passivation layer is located on the surface of the second doped conductive layer; the electrode penetrates through the passivation layer, and at least part of the electrode further penetrates through the second doped conductive layer to be in contact connection with the first doped conductive layer. And the photoelectric conversion efficiency of the photovoltaic cell can be improved.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the photovoltaic field, and in particular to a solar cell and a photovoltaic module. Background Art

[0002] Fossil energy causes air pollution and has limited reserves, while solar energy has the advantages of being clean, pollution-free and abundant in resources. Therefore, solar energy is gradually becoming the core clean energy to replace fossil energy. Since solar cells have good photoelectric conversion efficiency, they have become the focus of development of clean energy utilization.

[0003] For solar cells, the higher the photoelectric conversion efficiency, the better. Therefore, it is necessary to propose a solar cell with higher photoelectric conversion efficiency. Summary of the invention

[0004] The embodiments of the present disclosure provide a solar cell and a photovoltaic module, which can at least improve the photoelectric conversion efficiency of the solar cell.

[0005] According to some embodiments of the present disclosure, on one hand, an embodiment of the present disclosure provides a solar cell, comprising: a substrate, the substrate comprising a relative front side and a back side, and the substrate comprising metal areas and non-metal areas arranged alternately; a tunneling oxide layer, the tunneling oxide layer at least covers the non-metal area of ​​the front side; a first doped conductive layer, the first doped conductive layer is located on the metal area of ​​the front side, and the first doped conductive layer is doped with a first doping element and a second doping element, the first doping element is a metal element, and the second doping element is a non-metal element; a second doped conductive layer, the second doped conductive layer is located on the surfaces of the tunneling oxide layer and the first doped conductive layer, and the second doped conductive layer is doped with the first doping element; a passivation layer, the passivation layer is located on the surface of the second doped conductive layer; an electrode, the electrode penetrates the passivation layer, and at least part of the electrode also penetrates the second doped conductive layer to contact and connect with the first doped conductive layer.

[0006] In some embodiments, the thickness of the first doped conductive layer is greater than or equal to the thickness of the second doped conductive layer.

[0007] In some embodiments, the thickness of the first doped conductive layer is 2 nm to 150 nm, and the thickness of the second doped conductive layer is 2 nm to 50 nm.

[0008] In some embodiments, the electrode includes: a main body portion, which penetrates the passivation layer and contacts the second doped conductive layer; and a protrusion portion, which extends from the main body portion toward the substrate, and penetrates the second doped conductive layer and contacts the first doped conductive layer.

[0009] In some embodiments, the substrate includes: a protrusion, the protrusion corresponds to the metal area, the top surface of the protrusion protrudes from the top surface of the non-metal area of ​​the substrate, the tunneling oxide layer also covers the side wall of the protrusion, and the second doped conductive layer is also located on the surface of the tunneling oxide layer on the side wall of the protrusion.

[0010] In some embodiments, the sidewall of the protrusion has a plurality of light collecting structures with parabolic surfaces.

[0011] In some embodiments, the surface of the metal region of the substrate has a positive pyramid structure, and the surface of the non-metal region of the substrate has an inverted pyramid structure.

[0012] In some embodiments, a concentration of the first doping element in the first doped conductive layer is less than or equal to a concentration of the first doping element in the second doped conductive layer.

[0013] In some embodiments, the doping concentration of the first doping element of the first doped conductive layer is 1E17 / cm 3 ~1E21 / cm 3 , and / or, the doping concentration of the second doping element in the first doped conductive layer is 1E17 / cm 3 ~1E21 / cm 3 , and / or, the doping concentration of the first doping element in the second doped conductive layer is 1E17 / cm 3 ~1E21 / cm 3 .

[0014] According to some embodiments of the present disclosure, on the other hand, a photovoltaic module is provided, comprising: a battery string formed by connecting a plurality of solar cells as described in any one of claims 1 to 9; a packaging film for covering the surface of the battery string; and a cover plate for covering the surface of the packaging film facing away from the battery string.

[0015] The technical solution provided by the embodiments of the present disclosure has at least the following advantages: the substrate is used to collect light and generate photogenerated carriers, the tunneling oxide layer is used to chemically passivate the surface of the substrate, for the position corresponding to the metal area, a first doped conductive layer and a second doped conductive layer are stacked, and the first doped conductive layer is doped with metal elements and non-metal elements, which can reduce the recombination of the metal area, for the position corresponding to the non-metal area, only the second doped conductive layer is used for covering, and the substrate is further passivated by the second doped conductive layer to reduce the Auger recombination of the non-metal area, and at the same time, by arranging at least part of the electrode to pass through the second doped conductive layer and contact with the first doped conductive layer, the contact resistance and current transmission of the metal area can be not affected, thereby improving the photoelectric conversion efficiency of the solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings, and these exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise specified, the pictures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the traditional technology, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic diagram of the structure of a solar cell provided by an embodiment of the present disclosure;

[0018] Figure 2 Another schematic diagram of the structure of a solar cell provided in one embodiment of the present disclosure;

[0019] Figure 3 A schematic diagram of a partially enlarged structure of a solar cell provided in one embodiment of the present disclosure;

[0020] Figure 4 A schematic diagram of a structure of a substrate under a microscope provided by an embodiment of the present disclosure;

[0021] Figure 5 A structural schematic diagram of a pyramid structure provided by an embodiment of the present disclosure;

[0022] Figure 6 Another structural schematic diagram of a pyramid structure provided by an embodiment of the present disclosure;

[0023] Figure 7 A schematic diagram of another structure of a pyramid structure provided by an embodiment of the present disclosure;

[0024] Figure 8A schematic diagram of another structure of a pyramid structure provided by an embodiment of the present disclosure;

[0025] Fig. 9 A schematic diagram of a three-dimensional structure of a photovoltaic assembly provided in an embodiment of the present disclosure;

[0026] Fig.10 A schematic diagram of a cross-sectional structure of a photovoltaic module provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0027] As known from the background art, the doped conductive layer corresponding to the metal region of the solar cell is usually doped with metal elements. Although metal doping can reduce the contact resistance between the electrode and the doped conductive layer, metal doping can also cause serious recombination.

[0028] The disclosed embodiment provides a solar cell, wherein a substrate is used to collect light and generate photogenerated carriers, and a tunneling oxide layer is used to chemically passivate the surface of the substrate. For a position corresponding to a metal area, a first doped conductive layer and a second doped conductive layer are stacked, and the first doped conductive layer is doped with metal elements and non-metal elements, so that the recombination of the metal area can be reduced. For a position corresponding to a non-metal area, only the second doped conductive layer is used for covering, and the substrate is further passivated by the second doped conductive layer to reduce the Auger recombination of the non-metal area. At the same time, by arranging at least part of the electrode to pass through the second doped conductive layer and contact with the first doped conductive layer, the contact resistance and current transmission of the metal area can be not affected, thereby improving the photoelectric conversion efficiency of the solar cell.

[0029] In the description of the embodiments of the present disclosure, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present disclosure, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0030] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present disclosure. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0031] In the description of the embodiments of the present disclosure, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0032] In the description of the embodiments of the present disclosure, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0033] In the description of the embodiments of the present disclosure, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of the present disclosure and simplifying the description. They do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the embodiments of the present disclosure.

[0034] In the description of the embodiments of the present disclosure, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to the specific circumstances.

[0035] In the accompanying drawings corresponding to the embodiments of the present disclosure, the thickness and area of ​​the layers are magnified for better understanding and ease of description. When describing a component (such as a layer, a film, a region or a substrate) on another component or on the surface of another component, the component may be "directly" located on the surface of the other component, or a third component may be present between the two components. On the contrary, when describing a component on the surface of another component or when another component is formed or provided on the surface of a component, it means that there is no third component between the two components. In addition, when describing a component as being "substantially" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a partial edge of the entire surface.

[0036] In the description of the embodiments of the present disclosure, when a component "includes" another component, unless otherwise specified, other components are not excluded, and other components may be further included. In addition, when a component such as a layer, a film, a region, or a plate is referred to as being "on / located on" another component, it may be "directly on" the other component (i.e., located on the surface of the other component with no other components between them), or another component may exist in between. In addition, when a component such as a layer, a film, a region, a plate, etc. is "directly located on" another component, or when a component such as a layer, a film, a region, a plate, etc. is located on the surface of another component, it means that no other components are located in between.

[0037] The terms used in the description of the various embodiments described herein are only used to describe specific embodiments and are not intended to be limiting. As used in the description of the various embodiments described and in the appended claims, "the components" are also intended to include plural forms unless the context clearly indicates otherwise. Among them, components include components such as layers, films, regions, or plates.

[0038] The following will describe the various embodiments of the present disclosure in detail with reference to the accompanying drawings. However, it will be appreciated by those skilled in the art that in the various embodiments of the present disclosure, many technical details are provided in order to enable the reader to better understand the present disclosure. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present disclosure can be implemented.

[0039] refer to Figures 1 to 3 , Figure 1 A schematic diagram of the structure of a solar cell provided in one embodiment of the present disclosure is shown in FIG. Figure 2 Another schematic diagram of the structure of a solar cell provided in one embodiment of the present disclosure; Figure 3 for Figure 2 Schematic diagram of the local enlarged structure in the elliptical dotted box.

[0040] In some embodiments, a solar cell may include a substrate 100 , wherein the substrate 100 includes a front surface 110 and a back surface 120 opposite to each other, and the substrate 100 includes metal regions 130 and non-metal regions 140 arranged alternately.

[0041] The solar cell may include: a tunneling oxide layer 101 , wherein the tunneling oxide layer 101 at least covers the non-metallic region 140 of the front side 110 .

[0042] The solar cell may include: a first doped conductive layer 102, which is located on the metal area 130 of the front side 110 and is doped with a first doping element and a second doping element, wherein the first doping element is a metal element and the second doping element is a non-metal element.

[0043] The solar cell may include: a second doped conductive layer 103 , the second doped conductive layer 103 is located on the surfaces of the tunneling oxide layer 101 and the first doped conductive layer 102 , and the second doped conductive layer 103 is doped with a first doping element.

[0044] The solar cell may include: a passivation layer 104 , and the passivation layer 104 is located on the surface of the second doped conductive layer 103 .

[0045] The solar cell may include: an electrode 105 , wherein the electrode 105 penetrates the passivation layer 104 , and at least a portion of the electrode 105 also penetrates the second doped conductive layer 103 and contacts and connects with the first doped conductive layer 102 .

[0046] The embodiment of the present disclosure provides a solar cell, wherein a substrate 100 is used to collect light and generate photogenerated carriers, and a tunneling oxide layer 101 is used to chemically passivate the surface of the substrate 100. For a position corresponding to a metal region 130, a first doped conductive layer 102 and a second doped conductive layer 103 are stacked, and the first doped conductive layer 102 is doped with metal elements and non-metal elements, so that the recombination in the metal region 130 can be reduced. For a position corresponding to a non-metal region 140, only the second doped conductive layer 103 is used to cover the position, and the substrate 100 is further passivated by the second doped conductive layer 103 to reduce the Auger recombination of the non-metal region 140. At the same time, by arranging at least a portion of the electrode 105 to penetrate the second doped conductive layer 103 and contact the first doped conductive layer 102, the contact resistance and current transmission of the metal region 130 can be not affected, thereby improving the photoelectric conversion efficiency of the solar cell.

[0047] For the metal region 130 and the non-metal region 140 of the substrate 100 , the metal region 130 is the portion of the substrate 100 directly facing the electrode 105 .

[0048] In some embodiments, the solar cell is a single-sided cell, then the front side 110 of the substrate 100 can be used as a light-receiving surface for receiving incident light, and the back side 120 can be used as a backlight surface. In some embodiments, the solar cell is a double-sided cell, then both the front side and the back side of the substrate can be used as light-receiving surfaces, and both can be used to receive incident light. It can be understood that the backlight surface referred to in the embodiments of the present disclosure can also receive incident light, but the degree of receiving the incident light is weaker than the degree of receiving the incident light by the light-receiving surface, and therefore it is defined as a backlight surface.

[0049] In some embodiments, a texturing process may be performed on at least one of the front surface 110 or the back surface 120 of the substrate 100 to form a velvet surface on at least one of the front surface 110 or the back surface 120 of the substrate 100, so that the absorption utilization rate of the incident light by the front surface 110 and the back surface 120 of the substrate 100 can be enhanced. In some embodiments, the velvet surface may be a pyramid velvet surface, which, as a common velvet surface, not only reduces the reflectivity of the surface of the substrate 100, but also forms a light trap, thereby enhancing the absorption effect of the substrate 100 on the incident light and improving the photoelectric conversion efficiency of the solar cell.

[0050] In some embodiments, the material of the tunnel oxide layer 101 may be silicon oxide, aluminum oxide, or silicon oxide or a combination thereof.

[0051] It can be understood that, for the first doped conductive layer 102, if only metal elements are doped, due to the less effective doping of metal elements, the contact performance between the electrode 105 and the first doped conductive layer 102 is limited, resulting in a higher contact resistance between the electrode 105 and the first doped conductive layer 102. Therefore, for the first doped conductive layer 102, doping with metal elements and non-metal elements at the same time can reduce the recombination of the metal area 130 while reducing the contact resistance between the electrode 105 and the first doped conductive layer 102.

[0052] In some embodiments, the metal element doped in the first doped conductive layer 102 may be aluminum. The doping technology of aluminum is relatively mature, which can reduce the difficulty of doping. Moreover, the cost of aluminum is relatively low, which can reduce the cost of solar cells while having a good doping effect. In other embodiments, the metal element doped in the first doped conductive layer 102 may also be gallium or indium, etc.

[0053] In some embodiments, the non-metallic element doped into the first doped conductive layer 102 may be boron.

[0054] In some embodiments, the metal element and the non-metal element doped in the first doped conductive layer 102 may be elements of the same group. The elements of the same group provide the same number of electrons or holes to the first doped conductive layer 102, which will not affect the performance of the first doped conductive layer 102. Moreover, the metal element and the non-metal element, which are elements of the same group, will not interfere with each other, thereby improving the reliability of the solar cell.

[0055] For the second doped conductive layer 103 , the second doped conductive layer 103 needs to improve the passivation effect. Therefore, the second doped conductive layer 103 may be doped with only metal elements, thereby further improving the passivation effect of the second doped conductive layer 103 and further improving the performance of the solar cell.

[0056] In some embodiments, the thickness of the first doped conductive layer 102 is greater than or equal to the thickness of the second doped conductive layer 103 . It can be understood that the greater the thickness of the first doped conductive layer 102, the stronger the ability to improve the overall recombination of the entire first doped conductive layer 102 and the second doped conductive layer 103. Moreover, for the second doped conductive layer 103, the passivation effect of the second doped conductive layer 103 is better, but the second doped conductive layer 103 will cause the loss of the collection current. Moreover, for the non-metallic area 140, the non-metallic area 140 is not blocked by the electrode 105, and the light absorption capacity needs to be considered more. For the metal area 130, the electrode 105 exists in the metal area 130, and the light absorption capacity of the metal area 130 itself will be affected. What needs to be considered more is the passivation contact of the metal area 130. Therefore, setting the thickness of the first doped conductive layer 102 to be greater than or equal to the thickness of the second doped conductive layer 103 can reduce the recombination of the metal area 130 while improving the passivation contact capacity of the metal area 130. In addition, for the non-metallic area 140, it also avoids affecting the light absorption capacity of the non-metallic area 140, thereby further improving the photoelectric conversion efficiency of the solar cell.

[0057] In some embodiments, the thickness of the first doped conductive layer 102 is 2nm to 150nm, for example, 10nm, 20nm, 35nm, 48nm, 56nm, 67nm, 88nm, 93nm, 106nm, 128nm or 142nm, etc., and the thickness of the second doped conductive layer 103 is 2nm to 50nm, for example, 7nm, 15nm, 23nm, 33nm or 48nm, etc.

[0058] For the first doped conductive layer 102, the greater the thickness of the first doped conductive layer 102, the stronger the ability to improve the overall recombination of the entire first doped conductive layer 102 and the second doped conductive layer 103. At the same time, the greater the thickness of the first doped conductive layer 102, the greater the difficulty in forming the first doped conductive layer 102 with uniform distribution of internal doping elements. It is easy to cause the doping concentration on the side far away from the substrate 100 to be high and the doping concentration on the side close to the substrate 100 to be low, resulting in the effect of reducing the recombination of the metal area 130 failing to meet the expectations. Therefore, setting the thickness of the first doped conductive layer 102 to 2nm~150nm can improve the recombination of the metal area 130 while reducing the process difficulty of forming the first doped conductive layer 102.

[0059] For the second doped conductive layer 103, the greater the thickness of the second doped conductive layer 103, the stronger the passivation ability of the second doped conductive layer 103 is. However, in practice, for the metal region 130, the greater the thickness of the second doped conductive layer 103, the current collected on the electrode 105 will be lost on the second doped conductive layer 103. Therefore, setting the thickness of the second doped conductive layer 103 to 2nm to 50nm can make the second doped conductive layer 103 have a certain passivation effect while preventing the second doped conductive layer 103 from affecting the current transmission of the electrode 105.

[0060] In some embodiments, the thickness of the second doped conductive layer 103 located in the non-metal area 140 is greater than the thickness of the second doped conductive layer 103 located in the metal area 130. In this way, the passivation effect of the second doped conductive layer 103 in the non-metal area 140 can be improved while further preventing the second doped conductive layer 103 from affecting the current transmission of the electrode 105.

[0061] In some embodiments, the electrode 105 includes: a main body 115, the main body 115 penetrates the passivation layer 104 and contacts the second doped conductive layer 103; and a protrusion 125, the protrusion 125 extends from the main body 115 toward the substrate 100, and the protrusion 125 penetrates the second doped conductive layer 103 and contacts the first doped conductive layer 102. In other words, part of the electrode 105 contacts the second doped conductive layer 103, and part of the electrode 105 contacts the first doped conductive layer 102. For the second doped conductive layer 103, the second doped conductive layer 103 can facilitate the lateral transmission of carriers. Therefore, the second doped conductive layer 103 is provided in both the metal region 130 and the non-metal region 140 to facilitate the electrode 105 to collect carriers. The recombination of carriers on the second doped conductive layer 103 can be reduced while collecting carriers through part of the second doped conductive layer 103, thereby further improving the photoelectric conversion efficiency of the solar cell.

[0062] Combined with reference Figure 2 and Figure 4 ,in, Figure 4 A schematic diagram of the structure of a substrate under a microscope provided in one embodiment of the present disclosure.

[0063] In some embodiments, the substrate 100 includes: a protrusion 150, the protrusion 150 corresponds to the metal area 130, the top surface of the protrusion 150 protrudes from the top surface of the non-metal area 140 of the substrate 100, the tunneling oxide layer 101 also covers the sidewall of the protrusion 150, and the second doped conductive layer 103 is also located on the surface of the tunneling oxide layer 101 on the sidewall of the protrusion 150. In other words, the thickness of the portion of the substrate 100 corresponding to the metal area 130 is greater than the thickness of the portion corresponding to the non-metal area 140. By providing the substrate 100 with the protrusion 150, when the incident light irradiates the sidewall of the protrusion 150, the incident light can be reflected to the surface of the substrate 100, thereby improving the light absorption of the solar cell.

[0064] In some embodiments, the sidewall of the protrusion 150 has a plurality of light collecting structures with parabolic surfaces. It is understood that the protrusion 150 can also play a role in light absorption, and the provision of a plurality of parabolic light collecting structures on the sidewall of the protrusion 150 can improve the light absorption capacity on the protrusion 150, and can also improve the ability to reflect incident light to the surface of the substrate 100, thereby further improving the light absorption capacity of the solar cell.

[0065] It should be noted that a parabola is a surface obtained by rotating a parabola by 180°. In mathematics, a parabola is a set of points on the same plane whose distance to a fixed point (focus) is equal to the distance to a fixed straight line (directrix).

[0066] In some embodiments, the surface of the metal region 130 of the substrate 100 has a positive pyramid structure, and the surface of the non-metal region 140 of the substrate 100 has an inverted pyramid structure. For the metal region 130, the focus of the metal region 130 is the transmission of carriers, in other words, the contact resistance of the electrode 105 is considered, and the positive pyramid structure is set in the metal region 130 of the substrate 100, that is, the first doped conductive layer 102 corresponding to the metal region 130 will also present a positive pyramid structure, and the positive pyramid structure can increase the contact area between the electrode 105 and the first doped conductive layer 102, thereby reducing the contact resistance between the electrode 105 and the first doped conductive layer 102; for the non-metal region 140, the focus of the non-metal region 140 is the absorption of light, therefore, the inverted pyramid structure is set in the non-metal region 140 of the substrate 100 can increase the light absorption capacity of the solar cell.

[0067] In some embodiments, the size of the morphology of the metal area 130 of the substrate 100 is different from the size of the morphology of the non-metal area 140. Taking the example that the morphology of the metal area 130 and the morphology of the non-metal area 140 are both pyramid structures, the size of the pyramid morphology of the metal area 130 can be smaller than the morphology size of the non-metal area 140. For the metal area 130 with a smaller morphology size, its specific surface area is larger, resulting in the metal area 130 being rougher than the non-metal area 140, thereby increasing the contact area between the electrode 105 and the first doped conductive layer 102, thereby reducing the contact resistance between the electrode 105 and the first doped conductive layer 102.

[0068] In some embodiments, the size of the metal region 130 of the substrate 100 is different from that of the non-metal region 140 . Alternatively, the metal region 130 may be a positive pyramid structure, while the non-metal region 140 may be an inverted pyramid structure.

[0069] refer to Figures 5 to 8 ,in, Figure 5 A structural view under a microscope of a cross-sectional view of a top of a regular pyramid provided in one embodiment of the present disclosure, wherein the angle of the cross-sectional view is less than 90°; Figure 6 A structural view under a microscope of a cross-sectional view of a top of a regular pyramid provided in one embodiment of the present disclosure, wherein the angle of the cross-sectional view is greater than 90°; Figure 7 A structural view of an inverted pyramid structure under a microscope provided by an embodiment of the present disclosure; Figure 8 A structural view of a porous pyramid structure under a microscope provided in one embodiment of the present disclosure.

[0070] In some embodiments, the morphology of the non-metallic zone 140 can also be a right pyramid, wherein the angle of the cross-sectional view of the pyramid top can be less than 90°, or greater than 90°; in other embodiments, the morphology of the non-metallic zone 140 can also be an inverted pyramid; in yet other embodiments, the morphology of the non-metallic zone 140 can also be a porous pyramid.

[0071] In some embodiments, the concentration of the first doping element in the first doped conductive layer 102 is less than or equal to the concentration of the first doping element in the second doped conductive layer 103 . On the one hand, for the metal element, the metal element is used to improve the passivation effect of the first doped conductive layer 102 and the second doped conductive layer 103. For the first doped conductive layer 102, the first doped conductive layer 102 mainly considers the current transmission capability, and for the second doped conductive layer 103, the second doped conductive layer 103 mainly considers the passivation effect. Therefore, the concentration of the first doping element of the first doped conductive layer 102 is set to be less than or equal to the concentration of the first doping element of the second doped conductive layer 103. On the other hand, it is convenient to reduce the difficulty of the process. The doping element can be diffused into the first doped conductive layer 102 while doping the second doped conductive layer 103. It can be understood that, by using the diffusion method, the closer to the doping source, the greater the doping concentration will be, and the first doped conductive layer 102 is located on the side of the second doped conductive layer 103 away from the doping source. Therefore, the concentration of the first doping element of the first doped conductive layer 102 will be less than or equal to the concentration of the first doping element of the second doped conductive layer 103.

[0072] In some embodiments, the concentration of the first doping element of the first doped conductive layer 102 is less than or equal to the concentration of the second doping element. For the first doped conductive layer 102, the first doped conductive layer 102 mainly considers the current transmission capability. Therefore, by increasing the doping concentration of the non-metallic element, the contact resistance between the first doped conductive layer 102 and the electrode 105 can be reduced, thereby improving the photoelectric conversion efficiency of the solar cell.

[0073] In some embodiments, the doping concentration of the first doping element in the first doped conductive layer 102 is 1E17 / cm 3 ~1E21 / cm 3 , for example 1E18 / cm 3 、8.5E18 / cm 3 , 2E19 / cm 3 or 5E20 / cm 3 And / or, the doping concentration of the second doping element in the first doped conductive layer 102 is 1E17 / cm 3 ~1E21 / cm 3 , for example, 1.5E18 / cm 3 , 1E19 / cm 3 、7.3E19 / cm 3 or 8E20 / cm 3 And / or, the doping concentration of the first doping element in the second doped conductive layer 103 is 1E17 / cm 3 ~1E21 / cm 3, for example 3E18 / cm 3 、9.5E18 / cm 3 、4E19 / cm 3 or 8.6E20 / cm 3 etc.

[0074] By setting the doping concentration of the first doping element of the first doped conductive layer 102 to 1E17 / cm 3 ~1E21 / cm 3 The loss of current transmission in the first doped conductive layer 102 can be reduced, and the first doped conductive layer 102 can also have a certain passivation effect. By setting the doping concentration of the second doping element in the first doped conductive layer 102 to 1E17 / cm 3 ~1E21 / cm 3 The current transmission capacity of the first doped conductive layer 102 can be improved by setting the doping concentration of the first doping element of the second doped conductive layer 103 to 1E17 / cm 3 ~1E21 / cm 3 The passivation capability of the second doped conductive layer 103 can be increased while the loss of current transmission in the second doped conductive layer 103 can be reduced.

[0075] In some embodiments, the substrate 100 further includes: a back tunneling layer 106, a back doped conductive layer 107, a back passivation layer 108, and a back electrode 109, wherein the back tunneling layer 106 is located on the back side 120 of the substrate 100, the back doped conductive layer 107 is located on the surface of the back tunneling layer 106 away from the substrate 100, the back passivation layer 108 is located on the surface of the back doped conductive layer 107 away from the substrate 100, and the back electrode 109 penetrates the back passivation layer 108 and contacts and electrically connects with the back doped conductive layer 107. The back tunneling layer 106 is used to chemically passivate the back side 120 of the substrate 100, so that the majority carriers tunnel into the back doped conductive layer 107 while blocking the recombination of the minority carriers, the back doped conductive layer 107 is used to passivate the back side of the substrate 100, so that the sub-carriers are collected by the back electrode 109 through lateral transmission, and the back passivation layer 108 is used to passivate the back side of the substrate 100.

[0076] The embodiment of the present disclosure provides a solar cell, wherein a substrate 100 is used to collect light and generate photogenerated carriers, and a tunneling oxide layer 101 is used to chemically passivate the surface of the substrate 100. For a position corresponding to a metal region 130, a first doped conductive layer 102 and a second doped conductive layer 103 are stacked, and the first doped conductive layer 102 is doped with metal elements and non-metal elements, so that the recombination in the metal region 130 can be reduced. For a position corresponding to a non-metal region 140, only the second doped conductive layer 103 is used to cover the position, and the substrate 100 is further passivated by the second doped conductive layer 103 to reduce the Auger recombination of the non-metal region 140. At the same time, by arranging at least a portion of the electrode 105 to penetrate the second doped conductive layer 103 and contact the first doped conductive layer 102, the contact resistance and current transmission of the metal region 130 can be not affected, thereby improving the photoelectric conversion efficiency of the solar cell.

[0077] Another embodiment of the present disclosure further provides a photovoltaic module, which may include the solar cell in the above embodiment, or include a solar cell formed by the method for manufacturing the solar cell in the above embodiment. The method for manufacturing the solar cell provided by another embodiment of the present disclosure will be described below in conjunction with the accompanying drawings. It should be noted that the same or corresponding parts of the above embodiments can refer to the corresponding description of the above embodiments, and will not be repeated below.

[0078] refer to Fig. 9 and Fig.10 ,in, Fig. 9 A schematic diagram of a three-dimensional structure of a photovoltaic module provided in an embodiment of the present disclosure is shown in FIG. Fig.10 for Fig. 9 Cross-section along the M1M2 direction.

[0079] In some embodiments, a photovoltaic module may include: a battery string 20, which is composed of a plurality of solar cells such as some or all of the above embodiments; a packaging film 21, which is used to cover the surface of the battery string; and a cover plate 22, which is used to cover the surface of the packaging film 21 away from the battery string.

[0080] In some embodiments, the solar cell includes but is not limited to TOPCon cells (Tunnel Oxide Passivated Contact cells), stacked cells, or any combination thereof, wherein the stacked cells include but are not limited to perovskite cells stacked with TOPCon cells.

[0081] In some embodiments, the encapsulation film 21 includes a first encapsulation layer and a second encapsulation layer, the first encapsulation layer covers one of the front side or the back side of the solar cell, and the second encapsulation layer covers the other of the front side or the back side of the solar cell. Specifically, at least one of the first encapsulation layer or the second encapsulation layer can be an organic encapsulation film such as a polyvinyl butyral (PVB) film, an ethylene-vinyl acetate copolymer (EVA) film, a polyethylene octene co-elastomer (POE) film or a polyethylene terephthalate (PET) film.

[0082] It is worth noting that there is a boundary line between the first encapsulation layer and the second encapsulation layer before lamination. After lamination, the photovoltaic module is no longer a first encapsulation layer and a second encapsulation layer, that is, the first encapsulation layer and the second encapsulation layer have formed an integral encapsulation film 21.

[0083] In some embodiments, the cover plate 22 may be a glass cover plate, a plastic cover plate or the like with a light-transmitting function. Specifically, the surface of the cover plate 22 facing the encapsulation film 21 may be a concave-convex surface, thereby increasing the utilization rate of the incident light. The cover plate 22 includes a first cover plate and a second cover plate, the first cover plate is opposite to the first encapsulation layer, and the second cover plate is opposite to the second encapsulation layer; or the first cover plate is opposite to one side of the solar cell, and the second cover plate is opposite to the other side of the solar cell.

[0084] Those skilled in the art can understand that the above-mentioned embodiments are specific examples for implementing the present disclosure, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of the embodiments of the present disclosure. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of the present disclosure, so the protection scope of the embodiments of the present disclosure shall be based on the scope defined in the claims.

Claims

1. A solar cell, characterized in that: include: A substrate, the substrate comprising a front side and a back side opposite to each other, and the substrate comprising metal areas and non-metal areas arranged alternately; A tunneling oxide layer, wherein the tunneling oxide layer at least covers the non-metallic area of ​​the front surface; a first doped conductive layer, the first doped conductive layer being located on the metal region of the front surface, and the first doped conductive layer being doped with a first doping element and a second doping element, the first doping element being a metal element, and the second doping element being a non-metal element; a second doped conductive layer, the second doped conductive layer being located on surfaces of the tunnel oxide layer and the first doped conductive layer, and the second doped conductive layer being doped with the first doping element; a passivation layer, the passivation layer being located on a surface of the second doped conductive layer; An electrode penetrates the passivation layer, and at least a portion of the electrode also penetrates the second doped conductive layer to contact and connect with the first doped conductive layer.

2. The solar cell according to claim 1, characterized in that: The thickness of the first doped conductive layer is greater than or equal to the thickness of the second doped conductive layer.

3. The solar cell according to claim 1 or 2, characterized in that: The thickness of the first doped conductive layer is 2 nm to 150 nm, and the thickness of the second doped conductive layer is 2 nm to 50 nm.

4. The solar cell according to claim 1, characterized in that: The electrode comprises: a main body portion, the main body portion penetrating the passivation layer and contacting the second doped conductive layer; A protrusion extends from the main body toward the substrate, and the protrusion penetrates the second doped conductive layer and contacts and connects with the first doped conductive layer.

5. The solar cell according to claim 1, characterized in that: The substrate It includes: a protrusion, the protrusion corresponds to the metal area, the top surface of the protrusion protrudes from the top surface of the non-metal area of ​​the substrate, the tunneling oxide layer also covers the side wall of the protrusion, and the second doped conductive layer is also located on the surface of the tunneling oxide layer on the side wall of the protrusion.

6. The solar cell according to claim 5, characterized in that: The side wall of the protrusion has a plurality of light collecting structures with parabolic surfaces.

7. The solar cell according to claim 1 or 5, characterized in that: The surface of the metal region of the substrate has a positive pyramid structure, and the surface of the non-metal region of the substrate has an inverted pyramid structure.

8. The solar cell according to claim 1, characterized in that: A concentration of the first doping element in the first doped conductive layer is less than or equal to a concentration of the first doping element in the second doped conductive layer.

9. The solar cell according to claim 1 or 8, characterized in that: The doping concentration of the first doping element in the first doped conductive layer is 1E17 / cm 3 ~1E21 / cm 3 , and / or, the doping concentration of the second doping element in the first doped conductive layer is 1E17 / cm 3 ~1E21 / cm 3 , and / or, the doping concentration of the first doping element in the second doped conductive layer is 1E17 / cm 3 ~1E21 / cm 3 .

10. A photovoltaic module, characterized in that: include: A battery string, formed by connecting a plurality of solar cells as claimed in any one of claims 1 to 9; A packaging film, used to cover the surface of the battery string; The cover plate is used to cover the surface of the packaging film facing away from the battery string.

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