A method for preparing a solar cell, a solar cell, and a photovoltaic module.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-14
- Publication Date
- 2026-08-14
AI Technical Summary
然而，由于非晶硅材料的电子迁移率较低，电子在这些层内的运动受限，从而影响了电池的整体性能
[0038]该光伏组件包括太阳能电池，具备上述全部有益效果。
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Figure CN122579749A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of solar cell technology, and more specifically, to a method for preparing a solar cell, a solar cell, and a photovoltaic module. Background Technology
[0002] With the rapid development of photovoltaic technology, solar cells have also advanced rapidly and are widely used in industrial fields and other applications. In solar cells, amorphous silicon materials are often used as window layers or buffer layers to improve the photoelectric conversion performance of the cell. Amorphous silicon materials have important applications in the photovoltaic field due to their unique properties. However, the relatively low electron mobility of amorphous silicon materials limits their application in high-efficiency cells. Specifically, existing solar cell structures typically contain one or more amorphous silicon layers, which serve to reduce surface recombination and improve light absorption efficiency. However, due to the low electron mobility of amorphous silicon materials, the movement of electrons within these layers is restricted, thus affecting the overall performance of the cell. Especially under illumination conditions, rapid electron separation and collection are crucial for improving cell efficiency, but low electron mobility makes this process difficult, thereby limiting the efficiency improvement of solar cells.
[0003] Therefore, existing solar cells suffer from the technical problem of low electron mobility, which affects cell efficiency. Summary of the Invention
[0004] This invention provides a method for preparing a solar cell, a solar cell, and a photovoltaic module, which can improve the electron mobility of the solar cell, thereby helping to improve the battery efficiency.
[0005] The embodiments of the present invention can be implemented as follows:
[0006] An embodiment of the present invention provides a method for preparing a solar cell, comprising:
[0007] An intrinsic amorphous silicon layer is stacked on the first and / or second surfaces of a silicon substrate;
[0008] A nucleation layer is stacked on the surface of the intrinsic amorphous silicon layer on the side away from the silicon substrate.
[0009] A crystal nucleus incubation region is defined on the crystal nucleus incubation layer;
[0010] The crystal nucleus incubation region is heated to form nanocrystal nuclei;
[0011] A nanocrystalline silicon layer is formed at the location of the nanocrystalline nucleus.
[0012] Optionally, the step of determining the crystal nucleus incubation region on the crystal nucleus incubation layer includes:
[0013] The location of the seed crystals within the nucleus incubation layer is determined, and the location of the seed crystals is defined as the nucleus incubation region.
[0014] Optionally, the step of heating the nucleus incubation region to form nanocrystals includes:
[0015] The crystal nucleus incubation region is irradiated with a laser, and after the intrinsic amorphous silicon layer reaches a molten state, it is cooled to form nanocrystal nuclei in the crystal nucleus incubation region.
[0016] Optionally, the step of irradiating the nucleus incubation region with a laser, and then cooling the intrinsic amorphous silicon layer after it reaches a molten state to form nanocrystals in the nucleus incubation region includes:
[0017] The crystal nucleus incubation region was irradiated with a KrF excimer pulse; wherein the laser wavelength was 245nm-250nm, the pulse width was 12ns-14ns, the repetition frequency was 3Hz-7Hz, the spot size was 10mm×10mm, and the energy density was 210mJ / cm². 2 -250mJ / cm 2 ;or,
[0018] The crystal nucleus incubation area was irradiated with KrF excimer pulses; the number of laser irradiations was 45-52 times, and the laser treatment area was 210mm×105mm.
[0019] Optionally, the step of stacking a nucleation layer on the surface of the intrinsic amorphous silicon layer on the side away from the silicon substrate layer includes:
[0020] The intrinsic amorphous silicon layer is subjected to mixed gas plasma treatment on the side of the intrinsic amorphous silicon layer away from the silicon substrate layer, thereby promoting partial crystallization of the amorphous silicon surface and forming seed crystals to form a crystal nucleus incubation layer.
[0021] Optionally, the surface of the intrinsic amorphous silicon layer away from the silicon substrate is subjected to mixed gas plasma treatment, wherein the mixed gas used in the mixed gas plasma treatment includes hydrogen and carbon dioxide.
[0022] Optionally, the step of forming a nanocrystalline silicon layer at the location of the nanocrystalline nucleus includes:
[0023] The nanocrystalline silicon layer is doped with phosphorus or boron.
[0024] Optionally, the step of forming a nanocrystalline silicon layer at the location of the nanocrystalline nucleus includes:
[0025] A nanocrystalline silicon layer is formed at the location of the nanocrystalline nucleus using plasma-enhanced chemical vapor deposition (PECVD).
[0026] Embodiments of the present invention also provide a solar cell, including a silicon substrate layer, the silicon substrate layer including a first surface and a second surface disposed opposite to each other;
[0027] The first surface of the silicon substrate is provided with an intrinsic amorphous silicon layer, a crystal nucleation layer, a nanocrystalline silicon layer and a conductive metal oxide layer from the inside to the outside.
[0028] The second surface of the silicon substrate is provided with an intrinsic amorphous silicon layer, a crystal nucleation layer, a nanocrystalline silicon layer, and a conductive metal oxide layer from the inside out.
[0029] Optionally, the surface of the nucleus incubation layer away from the intrinsic amorphous silicon layer includes a plurality of nucleus incubation regions, and each of the plurality of nucleus incubation regions is formed with nanocrystal nuclei.
[0030] Optionally, the thickness of the crystal nucleus incubation layer is 0.5nm-1nm.
[0031] Optionally, the thickness of the nanocrystalline silicon layer is 12nm-35nm.
[0032] Embodiments of the present invention also provide a photovoltaic module, including a solar cell, the solar cell including a silicon substrate layer, the silicon substrate layer including a first surface and a second surface disposed opposite to each other;
[0033] The first surface of the silicon substrate is provided with an intrinsic amorphous silicon layer, a crystal nucleation layer, a nanocrystalline silicon layer and a conductive metal oxide layer from the inside to the outside.
[0034] The second surface of the silicon substrate is provided with an intrinsic amorphous silicon layer, a crystal nucleation layer, a nanocrystalline silicon layer, and a conductive metal oxide layer from the inside out.
[0035] The beneficial effects of the solar cell fabrication method, the solar cell, and the photovoltaic module according to embodiments of the present invention include, for example:
[0036] The method for fabricating this solar cell includes: stacking an intrinsic amorphous silicon layer on a first and / or second surface of a silicon substrate; stacking a nucleation layer on the surface of the intrinsic amorphous silicon layer away from the silicon substrate; defining a nucleation region on the nucleation layer; heating the nucleation region to form nanocrystals, and forming a nanocrystalline silicon layer at the location of the nanocrystals. In use, the nucleation layer is stacked on the surface of the amorphous silicon layer away from the silicon substrate. The nucleation layer promotes partial crystallization of the amorphous silicon surface. Then, a nucleation region on the nucleation layer is defined, and the nucleation region is heated so that the amorphous silicon reaches a molten state and is then rapidly cooled. The supercooling properties of amorphous silicon guide the material to form nanocrystals within the nucleation region, forming a nanocrystalline silicon layer at the location of the nanocrystals. Compared to existing solar cells, the nanocrystalline silicon layer has a higher electron mobility, which helps improve charge transport efficiency. Combining the advantages of amorphous silicon and nanocrystalline silicon improves crystallinity and thus cell efficiency.
[0037] This solar cell includes a silicon substrate layer, comprising a first surface and a second surface disposed opposite to each other. The first surface of the silicon substrate layer is sequentially disposed from the inside out with an intrinsic amorphous silicon layer, a nucleation layer, a nanocrystalline silicon layer, and a conductive metal oxide layer. The second surface of the silicon substrate layer is also sequentially disposed from the inside out with the same layers. In use, a nucleation layer is stacked on the surface of the amorphous silicon layer away from the silicon substrate layer. The nucleation layer promotes partial crystallization of the amorphous silicon surface. Nucleation regions on the nucleation layer are then defined and heated, causing the amorphous silicon to melt and then rapidly cooled. The supercooling properties of the amorphous silicon guide the formation of nanocrystalline nuclei within the nucleation regions, forming a nanocrystalline silicon layer at the location of these nuclei. Compared to existing solar cells, the nanocrystalline silicon layer exhibits higher electron mobility, which helps improve charge transport efficiency. Combining the advantages of amorphous silicon and nanocrystalline silicon improves crystallization rate and thus cell efficiency.
[0038] The photovoltaic module includes solar cells and has all the aforementioned beneficial effects. Attached Figure Description
[0039] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0040] Figure 1This is a schematic diagram of the structure of the solar cell provided in this embodiment.
[0041] Icons: 10-Silicon substrate; 101-First surface; 102-Second surface; 20-Intrinsic amorphous silicon layer; 30-Crystal nucleation layer; 301-Crystal nucleation region; 40-Nanocrystalline silicon layer; 50-Conductive metal oxide layer. Detailed Implementation
[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0043] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.
[0044] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0045] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.
[0046] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0047] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.
[0048] Please refer to Figure 1 This embodiment provides a method for preparing a solar cell, which can effectively improve the technical problems mentioned above, improve the electron mobility of the solar cell, and thus help improve the cell efficiency.
[0049] The method for preparing this solar cell includes:
[0050] S1: Prepare a single-crystal silicon substrate by texturing and cleaning the single-crystal silicon substrate using wet chemical methods.
[0051] S2: An intrinsic amorphous silicon layer 20 is stacked on the first surface 101 and / or the second surface 102 of the silicon substrate layer 10.
[0052] Specifically, the silicon substrate 10 includes a first surface 101 and a second surface 102 disposed opposite to each other, wherein the first surface 101 is the upper surface of the silicon substrate 10 and the second surface 102 is the lower surface of the silicon substrate 10, and an intrinsic amorphous silicon layer 20 is stacked on the first surface 101, that is, the upper surface of the silicon substrate 10.
[0053] In this embodiment, an intrinsic amorphous silicon layer 20 is prepared on the first surface 101 of the silicon substrate layer 10 using PECVD (Plasma Enhanced Chemical Vapor Deposition). The intrinsic amorphous silicon layer 20 comprises an undoped or lightly doped amorphous silicon film or an intrinsic silicon oxide film. Of course, the intrinsic amorphous silicon layer 20 may also comprise both an undoped or lightly doped amorphous silicon film and an intrinsic silicon oxide film; this is not specifically limited here.
[0054] Understandably, the intrinsic amorphous silicon layer 20 can help improve the light absorption efficiency of the cell and reduce recombination losses. The intrinsic amorphous silicon layer 20 can also serve as an interface isolation layer, reducing carrier recombination at the interface, thereby improving cell efficiency.
[0055] S3: A nucleus incubation layer 30 is stacked on the surface of the intrinsic amorphous silicon layer 20 on the side away from the silicon substrate layer 10.
[0056] Specifically, the surface of the intrinsic amorphous silicon layer 20 away from the silicon substrate layer 10 is subjected to mixed gas plasma treatment to promote partial crystallization of the amorphous silicon surface, so as to form seed crystals and ultimately form a crystal nucleus incubation layer 30.
[0057] It should be noted that the surface of the intrinsic amorphous silicon layer 20 away from the silicon substrate 10 is treated with a hydrogen and carbon dioxide mixed gas plasma. Hydrogen helps maintain or restore the hydrogen content in the intrinsic amorphous silicon layer 20, thereby ensuring the preservation of its electrical properties. Carbon dioxide plasma treatment promotes partial crystallization of the amorphous silicon surface, forming nanocrystals, providing a basis for subsequent vertical growth. Furthermore, the two-component plasma can seed nanocrystals on the shallow surface while limiting their disordered growth within the intrinsic amorphous silicon layer 20, preventing damage to the passivation quality.
[0058] S4: Define the nucleus incubation region 301 on the nucleus incubation layer 30.
[0059] Specifically, the location of the seed crystals within the nucleus incubation layer 30 is determined, and the location of the seed crystals is defined as the nucleus incubation region 301.
[0060] In this embodiment, there are several crystal nucleus incubation regions 301, which are arranged sequentially at intervals. Of course, the several crystal nucleus incubation regions 301 can be arranged in a matrix. No specific limitation is made here.
[0061] S5: Heating the crystal nucleus incubation region 301 to form nanocrystal nuclei.
[0062] Specifically, a laser is used to irradiate the crystal nucleus incubation region 301, and after the intrinsic amorphous silicon layer 20 reaches a molten state, it is cooled to form nanocrystal nuclei in the crystal nucleus incubation region 301.
[0063] It should be noted that the KrF excimer pulse was used to irradiate the crystal nucleus incubation region 301; the laser wavelength was 245nm-250nm, the pulse width was 12ns-14ns, the repetition frequency was 3Hz-7Hz, the spot size was 10mm×10mm, and the energy density was 210mJ / cm². 2 -250mJ / cm 2 The laser irradiation is performed 45-52 times, and the laser-treated area is 210mm × 105mm. Of course, the laser-treated area can be adjusted according to the shape and size of the silicon wafer, and no specific limit is given here.
[0064] Specifically, by locally heating the nucleus incubation layer 30 with a laser, a rapid and precise energy input is provided, allowing the amorphous silicon thin film to quickly reach a molten state in a specific area before cooling. This forms nanocrystals in the nucleus incubation region 301, improving the photoelectric conversion efficiency of the battery. This rapid thermal cycling process helps to form more nuclei in a shorter time, thereby increasing the crystallization rate.
[0065] Furthermore, local heating of the crystal nucleus incubation layer 30 using lasers can reduce the overall heating time and the energy required for heating, thereby accelerating the crystallization process.
[0066] Furthermore, by precisely controlling parameters such as laser energy density, pulse width, irradiation time, and pulse number, the growth rate and size of grains during crystallization can be precisely controlled, which helps to achieve a higher crystallization rate in a shorter time while ensuring the uniformity of grain size and distribution. By adjusting laser parameters, the size and distribution of crystal nuclei can be precisely controlled, thereby optimizing the growth of nanocrystalline silicon.
[0067] In this embodiment, during the process of heating the crystal nucleus incubation layer 30 with laser, only the crystal nucleus incubation area 301 on the crystal nucleus incubation layer 30 can be crystallized under the action of laser, thereby achieving local crystallization, reducing unnecessary overall heating and cooling processes, avoiding damage to the film layer by high temperature, saving time and improving production efficiency.
[0068] S6: A nanocrystalline silicon layer 40 is formed at the location of the nanocrystalline nucleus.
[0069] Specifically, a nanocrystalline silicon layer 40 is generated at the location where nanocrystalline nuclei have already formed on the nucleus incubation layer 30 using ion-enhanced chemical vapor deposition. Since the nucleus incubation layer 30 has already generated nuclei after step S5, the generation time of the nanocrystalline silicon layer 40 is accelerated, promoting the rapid growth of the nanocrystalline silicon layer 40. This helps optimize the quality of the growing nanocrystalline silicon layer 40 and improves the crystal quality of the nanocrystalline silicon layer 40. Compared with amorphous silicon layers, the nanocrystalline silicon layer 40 has a higher electron mobility, which helps improve the charge transport efficiency of the battery.
[0070] Specifically, the nanocrystalline silicon layer 40 is doped with phosphorus or boron, and oxygen doping or non-oxygen doping can be selected to improve carrier mobility and enhance the overall performance of the battery.
[0071] In this embodiment, the morphology of the nanocrystalline silicon layer 40 can be nanocrystalline silicon or microcrystalline silicon.
[0072] S7: A conductive metal oxide layer 50 is stacked on the surface of the nanocrystalline silicon layer 40 on the side away from the crystal nucleus incubation layer 30.
[0073] Specifically, a conductive metal oxide film is deposited on the surface of the nanocrystalline silicon layer 40 on the side away from the crystal nucleus incubation layer 30 using physical vapor deposition technology.
[0074] Please continue to refer to this. Figure 1 An embodiment of the present invention also provides a solar cell, including a silicon substrate 10, the silicon substrate 10 including a first surface 101 and a second surface 102 disposed opposite to each other; wherein, the first surface 101 of the silicon substrate 10 is provided with an intrinsic amorphous silicon layer 20, a crystal nucleation layer 30, a nanocrystalline silicon layer 40 and a conductive metal oxide layer 50 sequentially from the inside to the outside; the second surface 102 of the silicon substrate 10 is provided with an intrinsic amorphous silicon layer 20, a crystal nucleation layer 30, a nanocrystalline silicon layer 40 and a conductive metal oxide layer 50 sequentially from the inside to the outside.
[0075] In this embodiment, the thickness of the crystal nucleus incubation layer 30 is 0.5nm-1nm, and the thickness of the nanocrystalline silicon layer 40 is 12nm-35nm.
[0076] Embodiments of the present invention also provide a photovoltaic module, including the solar cell described above.
[0077] In summary, the embodiments of the present invention provide a method for preparing a solar cell, a solar cell, and a photovoltaic module. The method for preparing the solar cell includes stacking an intrinsic amorphous silicon layer 20 on the first surface 101 of a silicon substrate 10; stacking a nucleus incubation layer 30 on the side of the intrinsic amorphous silicon layer 20 away from the silicon substrate 10; defining a nucleus incubation region 301 on the nucleus incubation layer 30; heating the nucleus incubation region 301 to form nanonuclei; and forming a nanocrystalline silicon layer 40 at the location of the nanonuclei. In use, a nucleus incubation layer 30 is stacked on the surface of the amorphous silicon layer away from the silicon substrate 10. The nucleus incubation layer 30 can promote partial crystallization of the surface of the amorphous silicon layer. Then, a nucleus incubation region 301 on the nucleus incubation layer 30 is determined and heated so that the amorphous silicon reaches a molten state and is then rapidly cooled. The supercooling properties of amorphous silicon are used to guide the material to form nanocrystals in the nucleus incubation region 301. A nanocrystalline silicon layer 40 is formed at the location of the nanocrystals. Compared with solar cells in the prior art, the nanocrystalline silicon layer 40 has a higher electron mobility, which helps to improve charge transport efficiency. Combining the advantages of amorphous silicon and nanocrystalline silicon improves the crystallization rate and helps to improve the battery efficiency.
[0078] Compared to existing heterojunction solar cell fabrication methods, the solar cell fabrication method provided in this embodiment improves cell efficiency through laser crystallization technology without significantly increasing costs, avoiding the replacement of overall materials or large-scale process changes, thereby reducing costs.
[0079] This method for preparing solar cells can make full use of existing amorphous silicon thin film materials, combining the advantages of amorphous silicon and nanocrystalline silicon, thereby improving material utilization and making it more widely applicable.
[0080] The solar cell includes a silicon substrate 10, which includes a first surface 101 and a second surface 102 disposed opposite to each other. The first surface 101 of the silicon substrate 10 is provided with an intrinsic amorphous silicon layer 20, a crystal nucleation layer 30, a nanocrystalline silicon layer 40 and a conductive metal oxide layer 50 in sequence from the inside to the outside. The second surface 102 of the silicon substrate 10 is provided with an intrinsic amorphous silicon layer 20, a crystal nucleation layer 30, a nanocrystalline silicon layer 40 and a conductive metal oxide layer 50 in sequence from the inside to the outside. In use, a nucleus incubation layer 30 is stacked on the surface of the amorphous silicon layer away from the silicon substrate 10. The nucleus incubation layer 30 can promote partial crystallization of the surface of the amorphous silicon layer. Then, a nucleus incubation region 301 on the nucleus incubation layer 30 is determined and heated so that the amorphous silicon reaches a molten state and is then rapidly cooled. The supercooling properties of amorphous silicon are used to guide the material to form nanocrystals in the nucleus incubation region 301. A nanocrystalline silicon layer 40 is formed at the location of the nanocrystals. Compared with solar cells in the prior art, the nanocrystalline silicon layer 40 has a higher electron mobility, which helps to improve charge transport efficiency. Combining the advantages of amorphous silicon and nanocrystalline silicon improves the crystallization rate and helps to improve the battery efficiency.
[0081] Example 1
[0082] This embodiment provides a method for preparing a solar cell, including:
[0083] S1: Prepare a single-crystal silicon substrate by texturing and cleaning the single-crystal silicon substrate using wet chemical methods.
[0084] S2: Intrinsic amorphous silicon layers 20 are stacked on the first surface 101 and the second surface 102 of the silicon substrate layer 10, respectively.
[0085] Specifically, the silicon substrate 10 includes a first surface 101 and a second surface 102 disposed opposite to each other, wherein the first surface 101 is the upper surface of the silicon substrate 10 and the second surface 102 is the lower surface of the silicon substrate 10, and an intrinsic amorphous silicon layer 20 is stacked on the first surface 101, that is, the upper surface of the silicon substrate 10.
[0086] In this embodiment, an intrinsic amorphous silicon layer 20 is prepared on the first surface 101 of the silicon substrate layer 10 using PECVD (Plasma Enhanced Chemical Vapor Deposition). The intrinsic amorphous silicon layer 20 comprises an undoped or lightly doped amorphous silicon film or an intrinsic silicon oxide film. Of course, the intrinsic amorphous silicon layer 20 may also comprise both an undoped or lightly doped amorphous silicon film and an intrinsic silicon oxide film; this is not specifically limited here.
[0087] Understandably, the intrinsic amorphous silicon layer 20 can help improve the light absorption efficiency of the cell and reduce recombination losses. The intrinsic amorphous silicon layer 20 can also serve as an interface isolation layer, reducing carrier recombination at the interface, thereby improving cell efficiency.
[0088] S3: A nucleus incubation layer 30 is stacked on the surface of the intrinsic amorphous silicon layer 20 on the side away from the silicon substrate layer 10.
[0089] Specifically, the surface of the intrinsic amorphous silicon layer 20 away from the silicon substrate layer 10 is subjected to mixed gas plasma treatment to promote partial crystallization of the amorphous silicon surface, so as to form seed crystals and ultimately form a crystal nucleus incubation layer 30.
[0090] It should be noted that the surface of the intrinsic amorphous silicon layer 20 away from the silicon substrate 10 is treated with a hydrogen and carbon dioxide mixed gas plasma. Hydrogen helps maintain or restore the hydrogen content in the intrinsic amorphous silicon layer 20, thereby ensuring the preservation of its electrical properties. Carbon dioxide plasma treatment promotes partial crystallization of the amorphous silicon surface, forming nanocrystals, providing a basis for subsequent vertical growth. Furthermore, the two-component plasma can seed nanocrystals on the shallow surface while limiting their disordered growth within the intrinsic amorphous silicon layer 20, preventing damage to the passivation quality.
[0091] Specifically, the thickness of the crystal nucleus incubation layer 30 is 1 nm.
[0092] S4: Define the nucleus incubation region 301 on the nucleus incubation layer 30.
[0093] Specifically, the location of the seed crystals within the nucleus incubation layer 30 is determined, and the location of the seed crystals is defined as the nucleus incubation region 301.
[0094] In this embodiment, there are several crystal nucleus incubation regions 301, which are arranged sequentially at intervals. Of course, the several crystal nucleus incubation regions 301 can be arranged in a matrix. No specific limitation is made here.
[0095] S5: Heating the crystal nucleus incubation region 301 to form nanocrystal nuclei.
[0096] Specifically, a laser is used to irradiate the crystal nucleus incubation region 301, and after the intrinsic amorphous silicon layer 20 reaches a molten state, it is cooled to form nanocrystal nuclei in the crystal nucleus incubation region 301.
[0097] It should be noted that the KrF excimer pulse was used to irradiate the crystal nucleus incubation region 301; the laser wavelength was 248 nm, the pulse width was 13 ns, the repetition frequency was 5 Hz, the spot size was 10 mm × 10 mm, and the energy density was 210 mJ / cm². 2The laser irradiation was performed 50 times, and the laser treatment area was 210mm × 105mm.
[0098] S6: A nanocrystalline silicon layer 40 is formed at the location of the nanocrystalline nucleus.
[0099] Specifically, a nanocrystalline silicon layer 40 is generated at the location where nanocrystalline nuclei have already formed on the nucleus incubation layer 30 using ion-enhanced chemical vapor deposition. Since the nucleus incubation layer 30 has already generated nuclei after step S5, the generation time of the nanocrystalline silicon layer 40 is accelerated, promoting the rapid growth of the nanocrystalline silicon layer 40. This helps optimize the quality of the growing nanocrystalline silicon layer 40 and improves the crystal quality of the nanocrystalline silicon layer 40. Compared with amorphous silicon layers, the nanocrystalline silicon layer 40 has a higher electron mobility, which helps improve the charge transport efficiency of the battery.
[0100] Specifically, the nanocrystalline silicon layer 40 is doped with phosphorus or boron, and oxygen doping or non-oxygen doping can be selected to improve carrier mobility and enhance the overall performance of the battery.
[0101] In this embodiment, the morphology of the nanocrystalline silicon layer 40 can be nanocrystalline silicon or microcrystalline silicon.
[0102] Specifically, the thickness of the nanocrystalline silicon layer 40 is 20 nm.
[0103] S7: A conductive metal oxide layer 50 is stacked on the surface of the nanocrystalline silicon layer 40 on the side away from the crystal nucleus incubation layer 30.
[0104] Specifically, a conductive metal oxide film is deposited on the surface of the nanocrystalline silicon layer 40 on the side away from the crystal nucleus incubation layer 30 using physical vapor deposition technology.
[0105] Example 2
[0106] Referring to Example 1, the method for preparing the solar cell in this example differs from Example 1 in that, in step S5, a KrF excimer pulse is used to irradiate the nucleus incubation region 301; wherein the energy density is 230 mJ / cm². 2 The thickness of the nucleus incubation layer 30 is 1 nm, and the thickness of the nanocrystalline silicon layer 40 is 20 nm.
[0107] Example 3
[0108] Referring to Example 1, the method for fabricating the solar cell in this example differs from Example 1 in that, in step S5, a KrF excimer pulse is used to irradiate the nucleus incubation region 301; wherein the energy density is 250 mJ / cm². 2The thickness of the nucleus incubation layer 30 is 1 nm, and the thickness of the nanocrystalline silicon layer 40 is 20 nm.
[0109] Comparative Example 1
[0110] The method for preparing a solar cell provided in this comparative example is carried out in accordance with Example 1, except that laser processing is not used in the process of preparing the solar cell.
[0111] Comparative Example 2
[0112] The method is carried out in accordance with Example 1, but unlike Example 1, this comparative example provides a method for preparing a microcrystalline silicon heterojunction solar cell.
[0113] Test case
[0114] The short-circuit current, open-circuit voltage, conversion efficiency, and fill factor of the solar cells prepared by the methods provided in Examples 1-3 and Comparative Example 1, as well as the microcrystalline silicon heterojunction cells prepared by the method provided in Comparative Example 2, were tested. The results are shown in Table 1. The results of Examples 1-3 and Comparative Example 2 were normalized with the result of Comparative Example 1 as 1.0.
[0115] Table 1
[0116] Grouping information Short-circuit current Isc Open circuit voltage Voc Conversion efficiency Eta Fill factor FF Example 1 1.0218 1.0037 1.0293 1.0034 Example 2 1.0206 1.0042 1.0332 1.0080 Example 3 1.0219 1.0038 1.0296 1.0035 Comparative Example 2 1.0209 1.0042 1.0330 1.0075 Comparative Example 1 1.0000 1.0000 1.0000 1.0000
[0117] The results above show that, compared with Comparative Examples 1 and 2, the short-circuit current of the solar cells prepared by the solar cell preparation method provided in Examples 1-3 of the present invention is generally smaller than that of Comparative Examples 1 and 2, and the open-circuit voltage, fill factor and conversion efficiency are generally better than those of Comparative Examples 1 and 2.
[0118] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A method for preparing a solar cell, characterized in that, include: An intrinsic amorphous silicon layer (20) is stacked on the first surface (101) and / or the second surface of the silicon substrate layer (10); A nucleus incubation layer (30) is stacked on the surface of the intrinsic amorphous silicon layer (20) on the side away from the silicon substrate layer (10); A nucleus incubation region (301) is defined on the nucleus incubation layer (30); The nucleus incubation region (301) is heated to form nanocrystal nuclei; A nanocrystalline silicon layer (40) is formed at the location of the nanocrystalline nucleus.
2. The method for preparing a solar cell according to claim 1, characterized in that, The step of determining the nucleus incubation region (301) on the nucleus incubation layer (30) includes: The location of the seed crystal within the nucleus incubation layer (30) is determined, and the location of the seed crystal is defined as the nucleus incubation region (301).
3. The method for preparing a solar cell according to claim 1, characterized in that, The step of heating the nucleus incubation region (301) to form nanocrystal nuclei includes: The crystal nucleus incubation region (301) is irradiated with a laser, and after the intrinsic amorphous silicon layer (20) reaches a molten state, it is cooled to form nanocrystal nuclei in the crystal nucleus incubation region (301).
4. The method for preparing a solar cell according to claim 3, characterized in that, The step of irradiating the nucleus incubation region (301) with a laser, cooling the intrinsic amorphous silicon layer (20) after it reaches a molten state, and thereby forming nanocrystal nuclei in the nucleus incubation region (301) includes: The crystal nucleus incubation region (301) was irradiated with a KrF excimer pulse; wherein the laser wavelength was 245nm-250nm, the pulse width was 12ns-14ns, the repetition frequency was 3Hz-7Hz, the spot size was 10mm×10mm, and the energy density was 210mJ / cm². 2 -250mJ / cm 2 ;or, The crystal nucleus incubation region (301) was irradiated with KrF excimer pulses; the number of laser irradiations was 45-52 times, and the laser treatment area was 210mm×105mm.
5. The method for preparing a solar cell according to claim 1, characterized in that, The step of stacking a nucleation layer (30) on the surface of the intrinsic amorphous silicon layer (20) away from the silicon substrate layer (10) includes: The intrinsic amorphous silicon layer (20) is subjected to mixed gas plasma treatment on the side of the intrinsic amorphous silicon layer (20) away from the silicon substrate layer (10) to promote partial crystallization of the surface of the amorphous silicon and form seed crystals to form a crystal nucleus incubation layer (30).
6. The method for preparing a solar cell according to claim 5, characterized in that, The intrinsic amorphous silicon layer (20) is subjected to mixed gas plasma treatment on the side of the intrinsic amorphous silicon layer (20) away from the silicon substrate layer (10), wherein the mixed gas used in the mixed gas plasma treatment includes hydrogen and carbon dioxide.
7. The method for preparing a solar cell according to claim 1, characterized in that, The step of forming a nanocrystalline silicon layer (40) at the location of the nanocrystalline nucleus includes: The nanocrystalline silicon layer (40) is doped with phosphorus or boron.
8. The method for preparing a solar cell according to claim 1, characterized in that, The step of forming a nanocrystalline silicon layer (40) at the location of the nanocrystalline nucleus includes: A nanocrystalline silicon layer (40) is formed at the location of the nanocrystalline nucleus using plasma-enhanced chemical vapor deposition (PECVD).
9. A solar cell, characterized in that, It includes a silicon substrate layer (10), the silicon substrate layer (10) including a first surface (101) and a second surface (102) disposed opposite to each other; The first surface (101) of the silicon substrate layer (10) is provided with an intrinsic amorphous silicon layer (20), a crystal nucleation layer (30), a nanocrystalline silicon layer (40), and a conductive metal oxide layer (50) from the inside to the outside. The second surface (102) of the silicon substrate layer (10) is provided with an intrinsic amorphous silicon layer (20), a crystal nucleation layer (30), a nanocrystalline silicon layer (40), and a conductive metal oxide layer (50) from the inside to the outside.
10. The solar cell according to claim 9, characterized in that, The surface of the nucleus incubation layer (30) away from the intrinsic amorphous silicon layer (20) includes a plurality of nucleus incubation regions (301), and each of the plurality of nucleus incubation regions (301) is formed with nanocrystal nuclei.
11. The solar cell according to claim 9, characterized in that, The thickness of the nucleus incubation layer (30) is 0.5nm-1nm.
12. The solar cell according to claim 9, characterized in that, The thickness of the nanocrystalline silicon layer (40) is 12nm-35nm.
13. A photovoltaic module, characterized in that, The solar cell includes a silicon substrate (10) comprising a first surface (101) and a second surface (102) disposed opposite to each other. The first surface (101) of the silicon substrate layer (10) is provided with an intrinsic amorphous silicon layer (20), a crystal nucleation layer (30), a nanocrystalline silicon layer (40), and a conductive metal oxide layer (50) from the inside to the outside. The second surface (102) of the silicon substrate layer (10) is provided with an intrinsic amorphous silicon layer (20), a crystal nucleation layer (30), a nanocrystalline silicon layer (40), and a conductive metal oxide layer (50) from the inside to the outside.