Photovoltaic cell, preparation method thereof and photovoltaic module

Abstract

The invention provides a photovoltaic cell and a preparation method thereof, and a photovoltaic module, the photovoltaic cell comprises a substrate, the surface of the substrate comprises a first region, and the first region is provided with a first tunneling layer, a first doped polycrystalline silicon layer, a doped passivation layer, a second tunneling layer and a doped transmission layer which are far away from the surface of the substrate from inside to outside in sequence, wherein the doped passivation layer is a nitrogen-doped or carbon-doped passivation layer, the doping concentration of the doped passivation layer is greater than 5E18 atoms / cubic centimeter, the doped transmission layer is a transmission layer doped with third main group elements or doped with fifth main group elements of non-nitrogen elements, and the doping concentration of the doped transmission layer is greater than 1E18 atoms / cubic centimeter. According to the photovoltaic cell, parasitic absorption can be reduced, meanwhile, good contact is achieved, and high carrier transport efficiency is guaranteed.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of photovoltaic cells, and in particular to a photovoltaic cell and a preparation method thereof, and a photovoltaic module. Background Art

[0002] A photovoltaic cell (PV) is a component that converts solar energy into electrical energy. When sunlight strikes the semiconductor material on the surface of a PV cell, it absorbs the energy of the photons, allowing the electrons in the semiconductor atoms to gain enough energy to be released from their covalent bonds, forming free electrons. These free electrons then separate under the action of the electric field at the PN junction, forming a current that can drive the load.

[0003] Photovoltaic cells come in a wide variety of types, classified by their materials, structures, and operating principles. Structurally, they can be categorized into various types, including PERC (Passivated Emitter and Rear Cell), TOPCon (Tunnel Oxide Passivated Contact), HJT, and IBC (Interdigitated Back Contact). The distinction between front-junction and back-junction in photovoltaic cells is primarily based on the location of the PN junction and the layout of the metal contact electrodes. In front-junction cells, the metal grid electrodes and PN junction are located on the front side of the solar cell. Common front-junction cells include PERC, TOPCon, and heterojunction cells. Back-junction cells, for example, feature all electrode contacts located on the back side of the cell, leaving the front surface unobstructed. These include IBC and HBC (Heterojunction Back Contact) cells. In practical applications, back-junction and front-junction cells are often used in combination to leverage their respective strengths, thereby improving the overall efficiency and performance of the photovoltaic cell. For example, TOPCon cells can be combined with back contact technology to form TBC (Tunnel Oxide Passivated Contact Back Contact) cells, while HJT cells can be combined with back contact technology to form HBC cells, etc.

[0004] Whether it is a positive junction cell or a back junction cell, the front Poly finger structure (polycrystalline silicon finger) can solve the problem of reduced Jsc (short-circuit current density) caused by front shading, and the back Poly finger can solve the problem of large parasitic absorption of polysilicon due to full area coverage on the back. However, most measures to reduce parasitic absorption will lead to problems with carrier transport, resulting in poor contact. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a photovoltaic cell and a preparation method thereof, and a photovoltaic module, which reduce parasitic absorption while having good contact and ensuring high carrier transport efficiency.

[0006] To solve the above technical problems, in a first aspect, the present invention provides a photovoltaic cell, comprising: a substrate, the surface of which includes a first region; in the first region, away from the surface of the substrate, there are, in sequence from the inside to the outside, a first tunneling layer, a first doped polysilicon layer, a doped passivation layer, a second tunneling layer and a doped transport layer; wherein the doped passivation layer is a nitrogen-doped or carbon-doped passivation layer, and the doping concentration is greater than 5E18 atoms / cubic centimeter; the doped transport layer is a transport layer doped with a third main group element or a fifth main group element other than a nitrogen element, and the doping concentration is greater than 1E18 atoms / cubic centimeter.

[0007] Optionally, the surface of the substrate is suede.

[0008] Optionally, the doped passivation layer is a doped polysilicon layer, a microcrystalline silicon layer, or an amorphous silicon layer, and the doped transport layer is a doped polysilicon layer, a microcrystalline silicon layer, or an amorphous silicon layer.

[0009] Optionally, the doped transmission layer is a transmission layer doped with boron or phosphorus.

[0010] Optionally, a first aluminum oxide passivation layer and / or a first anti-reflection layer are sequentially formed on the doped transmission layer.

[0011] Optionally, the surface of the substrate further includes a second region, the second region is alternately distributed with the first region, and the second region has a second aluminum oxide passivation layer and / or a second anti-reflection layer in sequence from the inside to the outside away from the substrate surface.

[0012] Optionally, the material of the first anti-reflection layer and / or the second anti-reflection layer is one or more of the following materials: silicon dioxide, silicon nitride, zinc oxide, zinc sulfide, titanium oxide and silicon carbide.

[0013] In a second aspect, the present invention provides a photovoltaic assembly comprising the photovoltaic cell according to the first aspect, wherein the photovoltaic cells are electrically connected to form a photovoltaic cell string.

[0014] In a third aspect, the present invention provides a method for preparing a photovoltaic cell, comprising: providing a substrate, the surface of the substrate including a first region; sequentially preparing a first tunneling layer and a first doped polysilicon layer, a doped passivation layer, a second tunneling layer and a doped transport layer on the surface of the substrate; wherein the doped passivation layer is a nitrogen-doped or carbon-doped passivation layer, and the doping concentration is greater than 5E18 atoms / cubic centimeter; the doped transport layer is a transport layer doped with a third main group element or a fifth main group element other than a nitrogen element, and the doping concentration is greater than 1E18 atoms / cubic centimeter; and removing the first tunneling layer, the first doped polysilicon layer, the doped passivation layer, the second tunneling layer and the doped transport layer in a second region on the surface of the substrate, wherein the second region is a region of the substrate surface outside the first region.

[0015] Optionally, the first areas and the second areas are distributed alternately.

[0016] Optionally, the steps of sequentially preparing a first tunneling layer and a first doped polysilicon layer, a doped passivation layer, a second tunneling layer and a doped transport layer include: sequentially depositing an amorphous film containing nitrogen-doped or carbon-doped elements, a second tunneling layer, and an amorphous film containing a third main group element or a fifth main group element doped with a non-nitrogen element, and then performing an annealing process, wherein the amorphous film containing nitrogen-doped or carbon-doped elements forms the doped passivation layer after annealing, and the amorphous silicon film containing a third main group element or a fifth main group element doped with a non-nitrogen element forms the doped transport layer after annealing.

[0017] Optionally, the method further includes: sequentially preparing a first aluminum oxide passivation layer and / or a first anti-reflection layer on the doped transmission layer.

[0018] Optionally, the method further includes: in the second region, sequentially preparing a second aluminum oxide passivation layer and / or a second anti-reflection layer from the inside out away from the substrate surface.

[0019] Compared with the prior art, the present invention has the following advantages: the surface of the substrate includes a first region, and in the first region, away from the substrate surface, from the inside to the outside, there are a first tunneling layer, a first doped polysilicon layer, a doped passivation layer, a second tunneling layer and a doped transport layer, wherein the doped passivation layer is a nitrogen-doped or carbon-doped passivation layer with a doping concentration greater than 5E18 atoms / cubic centimeter, and the doped transport layer is a transport layer doped with a third main group element or a fifth main group element other than a nitrogen element, with a doping concentration greater than 1E18 atoms / cubic centimeter. Through the double-layer structure of the doped passivation layer and the doped transport layer, the photovoltaic cell can reduce parasitic absorption, achieve good contact, and ensure high carrier transport efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are included to provide a further understanding of the present application. They are incorporated into and constitute a part of this application. The accompanying drawings illustrate embodiments of the present application and, together with this specification, serve to explain the principles of the present application. In the accompanying drawings:

[0021] Figure 1 1 is a schematic structural diagram of a photovoltaic cell according to an embodiment of the present invention;

[0022] Figure 2 It is a schematic flow chart of a method for preparing a photovoltaic cell according to an embodiment of the present invention.

[0023] In the picture:

[0024] 110-base;

[0025] 121 - first tunneling layer, 122 - second tunneling layer, 123 - third tunneling layer;

[0026] 131 - a first doped polysilicon layer, 132 - a second doped polysilicon layer;

[0027] 140-doped passivation layer;

[0028] 150-doped transport layer;

[0029] 161 - first metal gate line, 162 - second metal gate line;

[0030] 171 - first aluminum oxide passivation layer, 172 - second aluminum oxide passivation layer, 173 - third aluminum oxide passivation layer;

[0031] 181 - first anti-reflection layer, 182 - second anti-reflection layer, 183 - third anti-reflection layer. DETAILED DESCRIPTION

[0032] To more clearly illustrate the technical solutions of the embodiments of this application, the following is a brief introduction to the drawings required for describing the embodiments. Obviously, the drawings described below are merely examples or embodiments of this application. Those skilled in the art can apply this application to other similar scenarios based on these drawings without inventive effort. Unless otherwise apparent from the context or otherwise noted, the same reference numerals in the figures represent the same structure or operation.

[0033] Unless otherwise specified, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. Technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0034] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is solely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. Furthermore, while the terms used in this application are selected from commonly known and commonly used terms, some terms mentioned in this specification may have been selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant sections of this description. Furthermore, this application should be understood not only by the actual terms used, but also by the meaning implied by each term.

[0035] In photovoltaic cells, the parasitic absorption coefficient of nitrogen-doped polysilicon (Poly) to light is significantly lower than that of boron-doped polysilicon, which can reduce front parasitic absorption. At the same time, the passivation performance of nitrogen-doped polysilicon is better than that of boron-doped polysilicon. Secondly, polysilicon films doped with nitrogen or carbon can achieve excellent passivation, but their electrical contact performance is reduced. The main reason may be that the activation of boron atoms or phosphorus atoms is suppressed, resulting in a larger contact barrier between the nitrogen-doped or carbon-doped polysilicon film and the metal, which cannot guarantee the effective transport of carriers. If the structure can be optimized, the parasitic absorption can be reduced and the high carrier transfer efficiency can be maintained, the power generation efficiency of photovoltaic cells will inevitably be greatly improved.

[0036] refer to Figure 1As shown, this embodiment provides a photovoltaic cell, which mainly includes a substrate 110. The surface of the substrate 110 includes a first region. In the first region, away from the substrate surface, from the inside to the outside, there are a first tunneling layer 121, a first doped polysilicon layer 131, a doped passivation layer 140, a second tunneling layer 122 and a doped transport layer 150, wherein the doped passivation layer 140 is a nitrogen-doped or carbon-doped passivation layer with a doping concentration greater than 5E18 atoms / cubic centimeter, and the doped transport layer 150 is a transport layer doped with a third main group element or a fifth main group element other than a nitrogen element, with a doping concentration greater than 1E18 atoms / cubic centimeter.

[0037] In this embodiment, the photovoltaic cell has a dual-functional layer structure, wherein the doping concentration of the doped passivation layer 140 is greater than 5E18 atoms / cm3, and the doping concentration of the doped transport layer 150 is greater than 1E18 atoms / cm3. Therefore, a layer of material with high passivation capability is used to achieve excellent interface passivation and carrier extraction, namely the doped passivation layer 140, and then covered with a layer of material with good contact performance to achieve carrier transport, namely the doped transport layer 150, to maximize the reduction of parasitic absorption while still maintaining good contact and ensuring high carrier transport efficiency. In addition, the photovoltaic cell of this embodiment is provided with a first tunneling layer 121 and a second tunneling layer 122. The two-layer tunneling layer structure serves as a channel for unidirectional carrier transmission, allowing only one type of carrier to pass through while inhibiting the transmission of the other type of carrier.

[0038] In this embodiment, the dual-functional layer structure having the doped passivation layer 140 and the doped transport layer 150 may be provided only on the front or back side of the substrate 110 , or may be provided on both the front and back sides of the substrate 110 .

[0039] The doped passivation layer 140 is a nitrogen-doped or carbon-doped passivation layer. Nitrogen-doped or carbon-doped passivation layers have significant advantages. Specifically, nitrogen-doped or carbon-doped passivation layers can increase the electron affinity of the material and form a stronger bond with the silicon substrate, thereby providing a better chemical passivation effect, reducing surface states and interface states, and reducing the surface recombination rate of carriers. In addition, after doping with nitrogen atoms or carbon atoms, fixed negative charges are formed on the silicon surface. These negative charges form a built-in electric field on the silicon surface, which helps reduce the probability of minority carrier recombination on the surface and achieve field-effect passivation.

[0040] The doped transport layer 150 is doped with a Group III element or a Group V element other than nitrogen. For example, Group III elements include boron (B), aluminum (Al), gallium (Ga), indium (In), and thallium (Tl), which can form a p-type doped polysilicon layer. Group V elements other than nitrogen include phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi), which can form an n-type doped polysilicon layer.

[0041] Furthermore, the doped transport layer 150 is a boron-doped or phosphorus-doped transport layer. Exemplarily, the doped transport layer 150 is a boron-doped or phosphorus-doped transport layer, and the doped passivation layer 140 is a nitrogen-doped or carbon-doped passivation layer. A second tunneling layer 122 is provided between the transport layer and the passivation layer. Furthermore, the doped passivation layer 140 improves the surface passivation effect and reduces parasitic absorption. The doped transport layer 150 also provides good contact and ensures high carrier transport efficiency.

[0042] In this embodiment, the doped passivation layer 140 is a doped polycrystalline silicon layer, a microcrystalline silicon layer, or an amorphous silicon layer, and the doped transport layer 150 can also be a doped polycrystalline silicon layer, a microcrystalline silicon layer, or an amorphous silicon layer. Although the doped passivation layer 140 and the doped transport layer 150 can be made of the same material in this embodiment, because the doped passivation layer 140 and the doped transport layer 150 are doped with different elements, they can achieve different effects respectively, so that the doped passivation layer 140 achieves excellent interface passivation and carrier extraction, and the doped transport layer 150 achieves carrier transport.

[0043] In one example, the surface of substrate 110 is velvet-finished. A velvet-finished surface on the substrate of a photovoltaic cell can reduce light reflectivity and increase light absorption, thereby improving the cell's photoelectric conversion efficiency. For example, the velvet-finished structure can resemble an inverted pyramid, which increases light absorption by increasing the number of reflections of incident light on the cell surface.

[0044] In one example, the doping transmission layer 150 is sequentially provided with a first aluminum oxide passivation layer 171 and / or a first anti-reflection layer 181 .

[0045] In one example, the surface of the substrate 110 further includes a second region, which is alternately distributed with the first region. The second region has a second aluminum oxide passivation layer 172 and / or a second anti-reflection layer 182 in sequence from the inside to the outside away from the substrate surface.

[0046] In this embodiment, aluminum oxide (Al2O3) can effectively passivate the surface of the photovoltaic cell, reduce defect states on the cell surface, and reduce surface recombination of carriers. The anti-reflection layer ARC (including the first anti-reflection layer 181 and the second anti-reflection layer 182) mainly increases the incidence of light and increases the current output of the photovoltaic cell. The anti-reflection layer can also reduce the reflection loss of the optical surface and increase the transmittance of light, thereby improving the efficiency of the photovoltaic cell. In this embodiment, the anti-reflection layer can be superimposed by materials with different refractive indices to prepare an anti-reflection film with excellent performance and reduce light reflection. It can be seen that the performance and efficiency of the photovoltaic cell can be significantly improved by providing an aluminum oxide passivation layer and / or an anti-reflection layer.

[0047] In this embodiment, the surface of the first aluminum oxide passivation layer 171 or the surface of the first anti-reflective layer 181 has a first metal gate line 161. Therefore, the first region where the first metal gate line 161 is located has a doped polysilicon layer, while the second region where the first metal gate line 161 is not located does not have a doped polysilicon layer, thereby forming a polysilicon finger structure (Poly finger).

[0048] In one example, the material of the first anti-reflection layer 181 and / or the second anti-reflection layer 182 is one or more of the following materials: silicon dioxide (SiO2), silicon nitride (Si3N4), zinc oxide (ZnO), zinc sulfide (ZnS), titanium oxide (TiO2) and silicon carbide (SiC).

[0049] In the photovoltaic cell of this embodiment, the surface of its substrate 110 includes a first region. In the first region, away from the substrate surface, from the inside to the outside, there are a first tunneling layer 121, a first doped polysilicon layer 131, a doped passivation layer 140, a second tunneling layer 122 and a doped transport layer 150. The doped passivation layer 140 is a nitrogen-doped or carbon-doped passivation layer with a doping concentration greater than 5E18 atoms / cubic centimeter. The doped transport layer 150 is a transport layer doped with a third main group element or a fifth main group element other than a nitrogen element with a doping concentration greater than 1E18 atoms / cubic centimeter. This can reduce parasitic absorption, ensure good contact, and ensure high carrier transport efficiency.

[0050] Another embodiment of the present invention provides a photovoltaic module, including photovoltaic cells as described in the aforementioned embodiments, wherein the photovoltaic cells are electrically connected to form a photovoltaic cell string, and one or more photovoltaic cell strings ultimately form a photovoltaic module (or photovoltaic system). The electrical connection methods of these photovoltaic cells include series connection and / or parallel connection. The series connection can increase the voltage of the entire module. When multiple photovoltaic cells are connected in series, their voltages are added together, which is beneficial for modules that require higher voltages (such as those connected to inverters or charging controllers). In addition, the series connection simplifies the wiring because there is only one current path, thereby reducing the number and size of wires required. The parallel connection can increase the total current output of the module while the voltage remains unchanged. This method provides better fault tolerance and flexibility because each photovoltaic cell works independently and the failure of one photovoltaic cell will not affect the operation of other photovoltaic cells.

[0051] In practical applications, photovoltaic modules or arrays are typically connected electrically in a combination of series and parallel configurations to achieve optimal energy yield and cost-effectiveness. For example, a certain number of photovoltaic cells can be connected in series and then connected in parallel. This increases both voltage and current, improving the overall performance of the module. The choice of connection method depends on the specific requirements of the module, the installation environment, and considerations of reliability and cost-effectiveness.

[0052] It can be understood that photovoltaic modules generally also include other conventional components, such as a packaging film for covering the surface of the photovoltaic module, a cover plate for covering the surface of the photovoltaic module facing away from the packaging film, etc. These other conventional components of the photovoltaic module will not be described here in detail and will not affect the understanding of the essential content of this embodiment.

[0053] In the photovoltaic module of this embodiment, the surface of the substrate 110 of the photovoltaic cell includes a first region. In the first region, away from the substrate surface, from the inside to the outside, there are a first tunneling layer, a first doped polysilicon layer, a doped passivation layer, a second tunneling layer and a doped transport layer. The doped passivation layer is a nitrogen-doped or carbon-doped passivation layer with a doping concentration greater than 5E18 atoms / cubic centimeter. The doped transport layer is a transport layer doped with a third main group element or a fifth main group element other than a nitrogen element with a doping concentration greater than 1E18 atoms / cubic centimeter. This can reduce parasitic absorption, ensure good contact, and ensure high carrier transport efficiency.

[0054] Another embodiment of the present invention provides a method for preparing a photovoltaic cell, referring to Figure 2 As shown, method 200 includes: S210, providing a substrate, the surface of the substrate including a first region; S220, sequentially preparing a first tunneling layer and a first doped polysilicon layer, a doped passivation layer, a second tunneling layer and a doped transport layer on the surface of the substrate; wherein the doped passivation layer is a nitrogen-doped or carbon-doped passivation layer, and the doping concentration is greater than 5E18 atoms / cubic centimeter; the doped transport layer is a transport layer doped with a third main group element or a fifth main group element other than a nitrogen element, and the doping concentration is greater than 1E18 atoms / cubic centimeter; S230, removing the first tunneling layer, the first doped polysilicon layer, the doped passivation layer, the second tunneling layer and the doped transport layer in a second region on the surface of the substrate, wherein the second region is a region of the substrate surface outside the first region.

[0055] In one example, the first areas and the second areas are distributed alternately.

[0056] In one example, the steps of sequentially preparing a first tunneling layer and a first doped polysilicon layer, a doped passivation layer, a second tunneling layer, and a doped transport layer include: sequentially depositing an amorphous film containing nitrogen-doped or carbon-doped elements, a second tunneling layer, and an amorphous film containing a third main group element or a fifth main group element doped with a non-nitrogen element, and then performing an annealing process, wherein the amorphous film containing nitrogen-doped or carbon-doped elements forms a doped passivation layer after annealing, and the amorphous silicon film containing a third main group element or a fifth main group element doped with a non-nitrogen element forms a doped transport layer after annealing.

[0057] In one example, a first aluminum oxide passivation layer and / or a first anti-reflection layer are sequentially formed on the doped transmission layer.

[0058] In one example, the method 200 further includes forming a second aluminum oxide passivation layer and / or a second anti-reflection layer in the second region, away from the substrate surface, from the inside to the outside.

[0059] The cell prepared by the photovoltaic cell preparation method of this embodiment has a first tunneling layer, a first doped polysilicon layer, a doped passivation layer, a second tunneling layer and a doped transport layer in the first region, away from the substrate surface, from the inside to the outside. The doped passivation layer is a nitrogen-doped or carbon-doped passivation layer with a doping concentration greater than 5E18 atoms / cubic centimeter, and the doped transport layer is a transport layer doped with a third main group element or a fifth main group element other than nitrogen, with a doping concentration greater than 1E18 atoms / cubic centimeter. This dual-functional layer structure can reduce parasitic absorption, ensure good contact, and ensure high carrier transport efficiency.

[0060] The basic concepts have been described above. It will be apparent to those skilled in the art that the above disclosures are merely illustrative and do not constitute limitations on this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and amendments to this application. Such modifications, improvements, and amendments are suggested in this application and remain within the spirit and scope of the exemplary embodiments of this application.

[0061] At the same time, this application uses specific terms to describe the embodiments of this application. For example, "one embodiment," "an embodiment," and / or "some embodiments" refer to a certain feature, structure, or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that "one embodiment," "an embodiment," or "an alternative embodiment" mentioned twice or multiple times in different locations in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this application may be appropriately combined.

[0062] Similarly, it should be noted that, in order to simplify the presentation of this application and thus facilitate understanding of one or more embodiments of the invention, the foregoing descriptions of the embodiments of this application sometimes combine multiple features into a single embodiment, figure, or description thereof. However, this disclosure method does not mean that the subject matter of this application requires more features than those recited in the claims. In fact, an embodiment may have fewer features than all of the features of a single embodiment disclosed above.

[0063] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions can be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the scope of the essential spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A photovoltaic cell, characterized in that: include: a substrate, a surface of the substrate including a first region; In the first region, away from the substrate surface, there are sequentially provided with a first tunneling layer, a first doped polysilicon layer, a doped passivation layer, a second tunneling layer and a doped transmission layer from the inside to the outside; The doped passivation layer is a nitrogen-doped or carbon-doped passivation layer with a doping concentration greater than 5E18 atoms / cubic centimeter; the doped transport layer is a transport layer doped with a third main group element or a fifth main group element other than a nitrogen element, with a doping concentration greater than 1E18 atoms / cubic centimeter.

2. The photovoltaic cell according to claim 1, wherein The surface of the substrate is suede.

3. The photovoltaic cell according to claim 1, wherein The doped passivation layer is a doped polysilicon layer, a microcrystalline silicon layer, or an amorphous silicon layer, and the doped transmission layer is a doped polysilicon layer, a microcrystalline silicon layer, or an amorphous silicon layer.

4. The photovoltaic cell according to claim 1, wherein The doped transmission layer is a transmission layer doped with boron or phosphorus.

5. The photovoltaic cell according to claim 1, wherein The doped transmission layer is sequentially provided with a first aluminum oxide passivation layer and / or a first anti-reflection layer.

6. The photovoltaic cell according to claim 5, wherein The surface of the substrate further includes a second region, which is alternately distributed with the first region. The second region has a second aluminum oxide passivation layer and / or a second anti-reflection layer in sequence from the inside to the outside away from the substrate surface.

7. The photovoltaic cell according to claim 6, wherein The material of the first anti-reflection layer and / or the second anti-reflection layer is one or more of the following materials: silicon dioxide, silicon nitride, zinc oxide, zinc sulfide, titanium oxide and silicon carbide.

8. A photovoltaic module, characterized in that: The photovoltaic cell comprises the photovoltaic cell according to any one of claims 1 to 7, wherein the photovoltaic cells are electrically connected to form a photovoltaic cell string.

9. A method for preparing a photovoltaic cell, characterized in that: include: Providing a substrate, wherein a surface of the substrate includes a first area; A first tunneling layer and a first doped polysilicon layer, a doped passivation layer, a second tunneling layer and a doped transport layer are sequentially formed on the surface of the substrate; wherein the doped passivation layer is a nitrogen-doped or carbon-doped passivation layer, and the doping concentration is greater than 5E18 atoms / cubic centimeter; the doped transport layer is a transport layer doped with a third main group element or a fifth main group element other than nitrogen, and the doping concentration is greater than 1E18 atoms / cubic centimeter; The first tunneling layer, the first doped polysilicon layer, the doped passivation layer, the second tunneling layer and the doped transport layer in a second region on the surface of the substrate are removed, wherein the second region is a region of the substrate surface outside the first region.

10. The method for preparing a photovoltaic cell according to claim 9, wherein: The first areas and the second areas are distributed alternately.

11. The method for preparing a photovoltaic cell according to claim 9, wherein: The steps of sequentially preparing a first tunneling layer, a first doped polysilicon layer, a doped passivation layer, a second tunneling layer, and a doped transport layer include: An amorphous film doped with nitrogen or carbon, a second tunneling layer, and an amorphous film containing a third main group element or a fifth main group element doped with a non-nitrogen element are sequentially deposited, and then an annealing process is performed. The amorphous film doped with nitrogen or carbon forms the doped passivation layer after annealing, and the amorphous silicon film containing a third main group element or a fifth main group element doped with a non-nitrogen element forms the doped transport layer after annealing.

12. The method for preparing a photovoltaic cell according to claim 9, wherein: Also includes: A first aluminum oxide passivation layer and / or a first anti-reflection layer are sequentially prepared on the doped transmission layer.

13. The method for preparing a photovoltaic cell according to claim 9, wherein: Also includes: In the second region, a second aluminum oxide passivation layer and / or a second anti-reflection layer is sequentially prepared from the inside to the outside away from the substrate surface.

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