Solar cell and preparation method thereof

Abstract

The invention relates to a solar cell and a preparation method thereof, and belongs to the technical field of solar cells. The solar cell comprises a window layer and an anti-reflection layer, and the anti-reflection layer is arranged on one side of the window layer. The material of the window layer comprises a GaInP material, and the material of the anti-reflection layer comprises a SiN material; the specific SiN material is selected as the window layer material to be matched with the antireflection layer of the solar cell made of the GaInP material, so that reflection can be reduced in a wide spectrum range, the light transmittance is increased, and the photoelectric conversion efficiency of the solar cell is further improved. And meanwhile, only one anti-reflection layer is arranged, so that the preparation difficulty is low.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to a solar cell and a method for preparing the same. Background Art

[0002] GaAs solar cells have become a recognized high-performance, long-life main power source in space due to their high photoelectric conversion efficiency, strong radiation resistance and excellent high temperature resistance, and have shown great potential in the field of civilian new energy.

[0003] However, the glass in the widely used solar devices has a light reflectivity of more than 8%, which leads to considerable energy loss and affects the photovoltaic / photothermal conversion efficiency. Although the existing double-layer or multi-layer anti-reflection film design can reduce reflection, the design and preparation process are relatively complex. Summary of the invention

[0004] The present application provides a solar cell and a method for preparing the same. The anti-reflection layer of the solar cell can be prepared using a simple process and has a good anti-reflection effect.

[0005] In a first aspect, the present application provides a solar cell, comprising a window layer and an anti-reflection layer, wherein the anti-reflection layer is disposed on one side of the window layer; a material of the window layer comprises a GaInP material, and a material of the anti-reflection layer comprises a SiN material.

[0006] In the above implementation process, by selecting a specific SiN material as the window layer material and combining it with the anti-reflection layer of the solar cell made of GaInP material, it is possible to reduce reflection in a wide spectral range, increase light transmittance, and thus improve the photoelectric conversion efficiency of the solar cell. At the same time, the anti-reflection layer has only one layer, and the preparation difficulty is relatively low.

[0007] As an optional implementation manner, the refractive index of the anti-reflection layer is 1-3.

[0008] In the above implementation process, by controlling the refractive index of the anti-reflection layer to be 1-3 and using the window layer made of GaInP material, the reflection of light can be effectively reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be improved.

[0009] As an optional implementation, the refractive index of the anti-reflection layer is 1.5-2.5.

[0010] In the above implementation process, by controlling the refractive index of the anti-reflection layer to 1.5-2.5 and using the window layer made of GaInP material, the reflection of light can be better reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be better improved.

[0011] As an optional implementation manner, the thickness of the anti-reflection layer is 70nm-95nm.

[0012] In the above implementation process, by controlling the thickness of the anti-reflection layer to be 70nm-95nm and using the window layer made of GaInP material, the reflection of light can be effectively reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be improved.

[0013] As an optional implementation manner, the thickness of the anti-reflection layer is 81nm-85nm.

[0014] In the above implementation process, by controlling the thickness of the anti-reflection layer to 81nm-85nm and using the window layer made of GaInP material, the reflection of light can be better reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be better improved.

[0015] As an optional implementation manner, the thickness of the window layer is 5 nm to 20 nm.

[0016] As an optional implementation, the difference between the refractive index of the window layer and the refractive index of the anti-reflection layer is less than 0.5.

[0017] In the above implementation process, the smaller the difference in refractive index between the window layer and the anti-reflection layer, the more beneficial it is to the light transmittance of the solar cell. By controlling the difference between the refractive index of the window layer and the refractive index of the anti-reflection layer to be less than 0.5, the reflection of light can be effectively reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be improved.

[0018] In a second aspect, the present application provides a method for preparing a solar cell, the method comprising:

[0019] Arranging a solar cell preparatory body on the pre-substrate, the solar cell preparatory body comprising a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer arranged in sequence in a direction away from the pre-substrate, and the material of the window layer comprises GaInP material;

[0020] The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is arranged on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are arranged in sequence close to the substrate;

[0021] An anti-reflection layer is arranged on the surface of the window layer and the reflector layer, and then a front electrode layer is arranged to obtain a solar cell, wherein the material of the anti-reflection layer includes SiN material.

[0022] In the above implementation process, by selecting a specific SiN material as the anti-reflection layer of the solar cell whose window layer material is GaInP material, it is possible to reduce reflection in a wide spectrum range, increase light transmittance, and thus improve the photoelectric conversion efficiency of the solar cell. At the same time, the anti-reflection layer has only one layer, and the preparation difficulty is relatively low.

[0023] As an optional implementation, the refractive index of the anti-reflection layer is 1 to 3; and / or

[0024] The thickness of the anti-reflection layer is 70nm-95nm.

[0025] As an optional implementation manner, the thickness of the window layer is 5nm to 20nm; and / or

[0026] The difference between the refractive index of the window layer and the refractive index of the anti-reflection layer is less than 0.5.

[0027] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0028] The solar cell provided in the embodiment of the present application can reduce reflection in a wide spectral range, increase light transmittance, and thus improve the photoelectric conversion efficiency of the solar cell by selecting a specific SiN material as the window layer material and combining it with the anti-reflection layer of the solar cell made of GaInP material. At the same time, the anti-reflection layer has only one layer, and the preparation difficulty is relatively low. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0031] Figure 1 A schematic diagram of the structure of a solar cell provided in an embodiment of the present application;

[0032] Figure 2 A schematic diagram of a process for a method provided in an embodiment of the present application;

[0033] Figure 3 A graph showing the relationship between the thickness of the anti-reflection layer and the relative current of the solar cell provided in an embodiment of the present application.

[0034] Figure numerals: 1 - substrate; 2 - back electrode layer; 3 - back field layer; 4 - base layer; 5 - emitter layer; 6 - window layer; 7 - anti-reflection layer; 8 - front electrode layer. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0036] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0037] The glass in current solar devices has a light reflectivity of more than 8%, which leads to considerable energy loss and affects the photovoltaic / photothermal conversion efficiency. The existing solution is to use double-layer or multi-layer anti-reflection film to reduce reflection, but the design and preparation process of these solutions are relatively complex.

[0038] To this end, the present application intends to provide a solar cell and a method for preparing the same, wherein the solar cell has only one anti-reflection layer, can be prepared using a simple process, and has a good anti-reflection effect.

[0039] Figure 1 A schematic diagram of the structure of a solar cell provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, an embodiment of the present application provides a solar cell, which includes a window layer and an anti-reflection layer, and the anti-reflection layer is arranged on one side of the window layer; the material of the window layer includes GaInP material, and the material of the anti-reflection layer includes SiN material.

[0040] The solar cell uses a specific SiN material as the window layer material and a GaInP material solar cell anti-reflection layer to reduce reflection in a wide spectrum range, increase light transmittance, and thus improve the photoelectric conversion efficiency of the solar cell. At the same time, the anti-reflection layer has only one layer, and the preparation difficulty is relatively low.

[0041] Usually, the structural layers of the entire solar cell include a substrate, a back electrode layer, a back field layer, a base layer, an emitter layer, a window layer, an anti-reflection layer and a front electrode layer, and the substrate, the back electrode layer, the back field layer, the base layer, the emitter layer, the window layer, the anti-reflection layer and the front electrode layer are stacked in sequence. Among them, the substrate layer is usually single crystal GaAs, which provides mechanical support and growth basis. The back electrode layer is usually made of metal (such as aluminum), collects the current generated from the base layer, and reflects the unabsorbed light back to the battery. The back field layer is generally p-type GaAs, which forms an electric field to help separate carriers and enhance efficiency. The base layer is a p-type GaAs (that is, the GaAs material is doped with a certain element (such as lithium or aluminum) to form a p-type semiconductor. Its main function is to absorb light energy and generate photogenerated carriers (electrons and holes)) layer, which is mainly used to absorb light energy and generate electron-hole pairs. The emitter layer is an n-type GaAs layer (i.e., GaAs material is doped with elements such as silicon to form an n-type semiconductor. Its main function is to provide excess electrons and enhance the conductivity of the battery). The front electrode layer is usually made of a metal material (such as silver) and is used to collect current and connect to an external circuit.

[0042] In some embodiments, the solar cell further includes a buffer layer, the buffer layer is located between the window layer and the emitter layer, and the crystalline silicon constant of the buffer layer matches the crystalline silicon constant of the window layer and the crystalline silicon constant of the emitter layer. The band gap width of the buffer layer is between the emitter layer and the window layer, which can well alleviate the lattice mismatch between the two, reduce the defects between the interfaces of the two, and further ensure that the solar cell has a high photoelectric conversion efficiency.

[0043] In order to better alleviate the lattice mismatch between the window layer and the emitter layer, in one embodiment of the present application, the material of the buffer layer includes In x Ga (1-x) P, where 0 <x<1。

[0044] In another embodiment of the present application, x=0.77, that is, the material of the buffer layer is In 0.77 Ga 0.23 P. This material can further alleviate the lattice mismatch problem between the window layer and the emitter layer, resulting in fewer defects at the interface between the two, thereby making the photoelectric conversion efficiency of the III-V solar cell higher.

[0045] In some embodiments, the solar cell further comprises a contact layer, which is located between the window layer and the front electrode layer. The material of the contact layer of the present application can be selected from any available material in the prior art, and those skilled in the art can select a suitable material to form the above-mentioned contact layer according to actual conditions.

[0046] In a specific embodiment, the material of the contact layer includes InGaP. The contact layer can further promote the movement of electrons or holes in the collection direction, thereby further improving the photoelectric conversion efficiency of the solar cell.

[0047] In some embodiments, the refractive index of the anti-reflection layer is 1 to 3. By controlling the refractive index of the anti-reflection layer to be 1 to 3 and combining it with a window layer made of GaInP material, the reflection of light can be effectively reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be improved.

[0048] Furthermore, the refractive index of the anti-reflection layer is 1.5 to 2.5. By controlling the refractive index of the anti-reflection layer to be 1.5 to 2.5 and combining it with a window layer made of GaInP material, the reflection of light can be better reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be better improved.

[0049] Illustratively, the refractive index of the antireflection layer may be 1, 1.2, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.7, 2.9 or 3, etc., and may also be any value within the range of 1 to 3.

[0050] In some embodiments, the thickness of the anti-reflection layer is 70nm to 95nm. By controlling the thickness of the anti-reflection layer to be 70nm to 95nm and combining it with a window layer made of GaInP material, the reflection of light can be effectively reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be improved.

[0051] Furthermore, the thickness of the anti-reflection layer is 81nm-85nm. By controlling the thickness of the anti-reflection layer to be 81nm-85nm and combining it with the window layer made of GaInP material, the reflection of light can be better reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be better improved.

[0052] Exemplarily, the thickness of the anti-reflection layer can be 70nm, 72nm, 74nm, 76nm, 78nm, 80nm, 82nm, 84nm, 86nm, 88nm, 90nm, 92nm, 94nm or 95nm, etc., and it can also be any value in the range of 70nm to 95nm.

[0053] In some embodiments, the thickness of the window layer is 5 nm to 20 nm. Exemplarily, the thickness of the window layer can be 5 nm, 7 nm, 9 nm, 11 nm, 13 nm, 15 nm, 17 nm, 19 nm or 20 nm, etc., and can also be any value within the range of 5 nm to 20 nm.

[0054] In some embodiments, the difference between the refractive index of the window layer and the refractive index of the anti-reflection layer is less than 0.5.

[0055] The smaller the refractive index difference between the window layer and the anti-reflection layer, the more beneficial it is to the light transmittance of the solar cell. By controlling the difference between the refractive index of the window layer and the refractive index of the anti-reflection layer to be less than 0.5, the reflection of light can be effectively reduced, the transmittance can be increased, and the photoelectric conversion efficiency of the solar cell can be improved.

[0056] Exemplarily, the difference between the refractive index of the window layer and the refractive index of the anti-reflection layer may be 0, 0.1, 0.2, 0.3, 0.4, 0.5, etc., and may also be any value less than 0.5.

[0057] Figure 2 A flow chart of the method provided in the embodiment of the present application is as follows: Figure 2 As shown, based on a general inventive concept, the present application embodiment also provides a method for preparing a solar cell

[0058] The method is used for preparing the above-mentioned solar cell. The specific content of the solar cell can refer to the above-mentioned embodiment. Since the method adopts part or all of the technical solutions of the above-mentioned embodiment, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiment, which will not be repeated here one by one.

[0059] In some embodiments, the method comprises:

[0060] S1. Arranging a solar cell preparation body on a pre-substrate, the solar cell preparation body comprising a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer arranged in sequence in a direction away from the pre-substrate, and the material of the window layer comprises a GaInP material;

[0061] S2. The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is disposed on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are sequentially disposed close to the substrate;

[0062] S3. An anti-reflection layer is arranged on the surface of the window layer and the reflector layer, and then a front electrode layer is arranged to obtain a solar cell, wherein the material of the anti-reflection layer includes SiN material.

[0063] This method uses a specific SiN material as the anti-reflection layer of a solar cell whose window layer material is GaInP material, which can reduce reflection in a wide spectral range, increase light transmittance, and thus improve the photoelectric conversion efficiency of the solar cell. At the same time, the anti-reflection layer has only one layer, and the preparation difficulty is relatively low.

[0064] In some embodiments, the anti-reflection layer is provided by chemical vapor deposition. By adopting chemical vapor deposition to prepare the anti-reflection layer, the prepared anti-reflection layer has a good anti-reflection effect, can be well matched with the window layer of GaInP material, can reduce reflection in a wide spectrum range, increase light transmittance, and thus improve the photoelectric conversion efficiency of the solar cell.

[0065] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following examples are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0066] Example 1

[0067] A solar cell comprises a substrate, a back electrode layer, a back field layer, a base layer, an emitter layer, a window layer, an anti-reflection layer and a front electrode layer, wherein the substrate, the back electrode layer, the back field layer, the base layer, the emitter layer, the window layer, the anti-reflection layer and the front electrode layer are stacked in sequence, the material of the window layer comprises a GaInP material, the material of the anti-reflection layer comprises a SiN material, the thickness of the anti-reflection layer is 70 nm, and the preparation process thereof is as follows:

[0068] S1. Arranging a solar cell preparation body on a pre-substrate, wherein the solar cell preparation body comprises a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer sequentially arranged in a direction away from the pre-substrate;

[0069] S2. The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is disposed on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are sequentially disposed close to the substrate;

[0070] S3. Using chemical vapor deposition to set an anti-reflection layer on the surface of the reflector layer according to the window layer principle, and then set a front electrode layer to obtain a solar cell.

[0071] Example 2

[0072] A solar cell comprises a substrate, a back electrode layer, a back field layer, a base layer, an emitter layer, a window layer, an anti-reflection layer and a front electrode layer, wherein the substrate, the back electrode layer, the back field layer, the base layer, the emitter layer, the window layer, the anti-reflection layer and the front electrode layer are stacked in sequence, the material of the window layer comprises a GaInP material, the material of the anti-reflection layer comprises a SiN material, the thickness of the anti-reflection layer is 75 nm, and the preparation process is as follows:

[0073] S1. Arranging a solar cell preparation body on a pre-substrate, wherein the solar cell preparation body comprises a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer sequentially arranged in a direction away from the pre-substrate;

[0074] S2. The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is disposed on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are sequentially disposed close to the substrate;

[0075] S3. Using chemical vapor deposition to set an anti-reflection layer on the surface of the reflector layer according to the window layer principle, and then set a front electrode layer to obtain a solar cell.

[0076] Example 3

[0077] A solar cell comprises a substrate, a back electrode layer, a back field layer, a base layer, an emitter layer, a window layer, an anti-reflection layer and a front electrode layer, wherein the substrate, the back electrode layer, the back field layer, the base layer, the emitter layer, the window layer, the anti-reflection layer and the front electrode layer are stacked in sequence, the material of the window layer comprises a GaInP material, the material of the anti-reflection layer comprises a SiN material, the thickness of the anti-reflection layer is 80 nm, and the preparation process is as follows:

[0078] S1. Arranging a solar cell preparation body on a pre-substrate, wherein the solar cell preparation body comprises a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer sequentially arranged in a direction away from the pre-substrate;

[0079] S2. The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is disposed on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are sequentially disposed close to the substrate;

[0080] S3. Using chemical vapor deposition to set an anti-reflection layer on the surface of the reflector layer according to the window layer principle, and then set a front electrode layer to obtain a solar cell.

[0081] Example 4

[0082] A solar cell comprises a substrate, a back electrode layer, a back field layer, a base layer, an emitter layer, a window layer, an anti-reflection layer and a front electrode layer, wherein the substrate, the back electrode layer, the back field layer, the base layer, the emitter layer, the window layer, the anti-reflection layer and the front electrode layer are stacked in sequence, the material of the window layer comprises a GaInP material, the material of the anti-reflection layer comprises a SiN material, the thickness of the anti-reflection layer is 85 nm, and the preparation process is as follows:

[0083] S1. Arranging a solar cell preparation body on a pre-substrate, wherein the solar cell preparation body comprises a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer sequentially arranged in a direction away from the pre-substrate;

[0084] S2. The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is disposed on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are sequentially disposed close to the substrate;

[0085] S3. Using chemical vapor deposition to set an anti-reflection layer on the surface of the reflector layer according to the window layer principle, and then set a front electrode layer to obtain a solar cell.

[0086] Example 5

[0087] A solar cell comprises a substrate, a back electrode layer, a back field layer, a base layer, an emitter layer, a window layer, an anti-reflection layer and a front electrode layer, wherein the substrate, the back electrode layer, the back field layer, the base layer, the emitter layer, the window layer, the anti-reflection layer and the front electrode layer are stacked in sequence, the material of the window layer comprises a GaInP material, the material of the anti-reflection layer comprises a SiN material, the thickness of the anti-reflection layer is 90 nm, and the preparation process is as follows:

[0088] S1. Arranging a solar cell preparation body on a pre-substrate, wherein the solar cell preparation body comprises a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer sequentially arranged in a direction away from the pre-substrate;

[0089] S2. The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is disposed on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are sequentially disposed close to the substrate;

[0090] S3. Using chemical vapor deposition to set an anti-reflection layer on the surface of the reflector layer according to the window layer principle, and then set a front electrode layer to obtain a solar cell.

[0091] Example 6

[0092] A solar cell comprises a substrate, a back electrode layer, a back field layer, a base layer, an emitter layer, a window layer, an anti-reflection layer and a front electrode layer, wherein the substrate, the back electrode layer, the back field layer, the base layer, the emitter layer, the window layer, the anti-reflection layer and the front electrode layer are stacked in sequence, the material of the window layer comprises a GaInP material, the material of the anti-reflection layer comprises a SiN material, the thickness of the anti-reflection layer is 95 nm, and the preparation process is as follows:

[0093] S1. Arranging a solar cell preparation body on a pre-substrate, wherein the solar cell preparation body comprises a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer sequentially arranged in a direction away from the pre-substrate;

[0094] S2. The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is disposed on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are sequentially disposed close to the substrate;

[0095] S3. Using chemical vapor deposition to set an anti-reflection layer on the surface of the reflector layer according to the window layer principle, and then set a front electrode layer to obtain a solar cell.

[0096] Example 7

[0097] A solar cell comprises a substrate, a back electrode layer, a back field layer, a base layer, an emitter layer, a window layer, an anti-reflection layer and a front electrode layer, wherein the substrate, the back electrode layer, the back field layer, the base layer, the emitter layer, the window layer, the anti-reflection layer and the front electrode layer are stacked in sequence, the material of the window layer comprises a GaInP material, the material of the anti-reflection layer comprises a SiN material, the thickness of the anti-reflection layer is 100 nm, and the preparation process is as follows:

[0098] S1. Arranging a solar cell preparation body on a pre-substrate, wherein the solar cell preparation body comprises a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer sequentially arranged in a direction away from the pre-substrate;

[0099] S2. The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is disposed on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are sequentially disposed close to the substrate;

[0100] S3. Using chemical vapor deposition to set an anti-reflection layer on the surface of the reflector layer according to the window layer principle, and then set a front electrode layer to obtain a solar cell.

[0101] The relative current of the solar cells provided in each embodiment was tested, and the results are as follows: Figure 3 As shown in the figure, it can be seen that when the thickness of the anti-reflection film made of SiN material is 70nm~95nm, the solar cell has a larger relative current, especially when the thickness is 81nm~85nm, it has a larger relative current. And it can be seen from the figure that the optimal thickness of the anti-reflection film is about 83nm.

[0102] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0103] In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the description of the present specification, the terms "including", "comprising", etc. refer to "including but not limited to". In this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of the associated objects, indicating that there may be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A, B can be singular or plural. In this article, "at least one" refers to one or more, and "plural" refers to two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, "at least one of a, b or c", or "at least one of a, b and c", can both mean: a, b, c, ab (i.e. a and b), ac, bc, or abc, where a, b and c can be single or multiple.

[0104] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A solar cell, characterized in that: The solar cell comprises a window layer and an anti-reflection layer, wherein the anti-reflection layer is arranged on one side of the window layer; the material of the window layer comprises GaInP material, and the material of the anti-reflection layer comprises SiN material.

2. The solar cell according to claim 1, characterized in that The refractive index of the anti-reflection layer is 1-3.

3. The solar cell according to claim 2, characterized in that: The refractive index of the anti-reflection layer is 1.5-2.

5.

4. The solar cell according to any one of claims 1 to 3, characterized in that The thickness of the anti-reflection layer is 70nm-95nm.

5. The solar cell according to claim 4, characterized in that: The thickness of the anti-reflection layer is 81nm-85nm.

6. The solar cell according to claim 1, characterized in that The thickness of the window layer is 5nm-20nm.

7. The solar cell according to claim 1, characterized in that The difference between the refractive index of the window layer and the refractive index of the anti-reflection layer is less than 0.

5.

8. A method for preparing a solar cell, characterized in that: The method comprises: Arranging a solar cell preparatory body on the pre-substrate, the solar cell preparatory body comprising a window layer, an emitter layer, a base layer, a back field layer, and a back electrode layer arranged in sequence in a direction away from the pre-substrate, and the material of the window layer comprises GaInP material; The solar cell preparation body is peeled off from the pre-substrate by epitaxial peeling technology, and is arranged on the substrate, and the window layer, the emitter layer, the base layer, the back field layer, and the back electrode layer are arranged in sequence close to the substrate; An anti-reflection layer is arranged on the surface of the window layer and the reflector layer, and then a front electrode layer is arranged to obtain a solar cell, wherein the material of the anti-reflection layer includes SiN material.

9. The method for preparing a solar cell according to claim 8, characterized in that: The refractive index of the anti-reflection layer is 1 to 3; and / or The thickness of the anti-reflection layer is 70nm-95nm.

10. The method for preparing a solar cell according to claim 8, characterized in that: The thickness of the window layer is 5nm to 20nm; and / or The difference between the refractive index of the window layer and the refractive index of the anti-reflection layer is less than 0.5.

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