Topcon solar cell with localized passivated contact structure and method of manufacturing the same, cell module

Abstract

The present disclosure provides a TOPCon solar cell with a localized passivation contact structure, a manufacturing method thereof, and a battery assembly. The TOPCon solar cell with the localized passivation contact structure comprises: a battery silicon wafer; a polysilicon stack layer arranged on a back surface of the battery silicon wafer; a dielectric layer arranged between the polysilicon stack layer and the battery silicon wafer; a groove extending along a thickness direction of the TOPCon solar cell and penetrating through the polysilicon stack layer and the dielectric layer; the polysilicon stack layer is divided into at least one localized area, the localized area comprises a first area and a second area surrounding the first area; and the groove is located in the first area and / or the second area in the TOPCon solar cell. The TOPCon solar cell of the present disclosure can reduce infrared free carrier absorption loss, improve passivation interface stability, alleviate film stress and film explosion risk, and enhance local carrier collection capability.

Description

Technical Field

[0001] This disclosure relates to the field of solar cell technology, and in particular to a TOPCon solar cell with a localized passivated contact structure, its manufacturing method, and cell module. Background Technology

[0002] Currently, TOPCon solar cells with poly-Si / SiOx passivated contacts based on the PECVD method have a high market share, and their photoelectric conversion efficiency is continuously improving. However, the poly-Si layer grown by the PECVD method has a high hydrogen content and poor crystallinity, making it prone to film bursting and exhibiting severe free carrier absorption. In addition, due to hydrogen plasma bombardment, the interfacial silicon oxide is easily damaged, limiting the improvement of open-circuit voltage.

[0003] To reduce the absorption of poly-Si, some researchers have proposed using CO2 plasma to dope poly-SiOx films and growing intrinsic i-poly-Si using LPCVD as a contact layer with tunneling silicon oxide. However, this method has the problem of silicon film coverage area and still has serious optical absorption. Summary of the Invention

[0004] This disclosure provides a TOPCon solar cell with a localized passivated contact structure, comprising: a silicon wafer; a polycrystalline silicon stack layer disposed on the back side of the silicon wafer; a dielectric layer disposed between the polycrystalline silicon stack layer and the silicon wafer; and a trench extending along the thickness direction of the TOPCon solar cell and penetrating the polycrystalline silicon stack layer and the dielectric layer; the polycrystalline silicon stack layer is divided into at least one localized region, the localized region including a first region and a second region surrounding the first region; in the TOPCon solar cell, the trench is located in the first region and / or the second region.

[0005] According to the TOPCon solar cell disclosed herein, the polycrystalline silicon stack layer includes: the trench located in a localized region of the first region; and / or the polycrystalline silicon stack layer includes the trench located in a localized region of the second region.

[0006] According to the TOPCon solar cell of this disclosure, the trench is located in the second region and extends around the first region.

[0007] According to the TOPCon solar cell of this disclosure, in the localized region, the area ratio of the first region and the second region is X∈(0,1).

[0008] According to the TOPCon solar cell disclosed herein, in the localized region, the specific surface area values ​​of the first region and the second region are 1 to 1.3.

[0009] According to the TOPCon solar cell disclosed herein, the polycrystalline silicon stack layer contains poly-SiO₂. x Or poly-SiC.

[0010] According to the TOPCon solar cell disclosed herein, the thickness of the polycrystalline silicon stack layer is 10-500 nm.

[0011] According to the TOPCon solar cell disclosed herein, the polycrystalline silicon stack layer contains poly-SiO₂. x The oxygen content is 0.05-20 at%.

[0012] According to the TOPCon solar cell of this disclosure, the first region and / or the second region are located in the non-metallic contact region of the TOPCon cell.

[0013] This disclosure also provides a method for manufacturing a TOPCon solar cell with a localized passivated contact structure, comprising: forming a dielectric layer and a polycrystalline silicon stack layer on the back side of a silicon wafer, the polycrystalline silicon stack layer being divided into at least one localized region, the localized region including a first region and a second region surrounding the first region; and forming, by laser processing, trenches extending along the thickness direction of the TOPCon solar cell and penetrating the polycrystalline silicon stack layer and the dielectric layer in the first region and / or the second region.

[0014] According to the manufacturing method disclosed herein, the manufacturing method further includes: sequentially forming an emitter layer, a surface passivation layer, and a front metal contact layer on the front side of the battery silicon wafer; and sequentially forming a back passivation layer and a back metal contact layer on the side of the polycrystalline silicon stack layer away from the battery silicon wafer.

[0015] The manufacturing method according to this disclosure includes: forming a dielectric layer and an intrinsic polycrystalline silicon layer (ipoly-Si) on the backlight side of a battery silicon wafer; forming an oxygen- or carbon-containing phosphorus-doped amorphous silicon layer on the intrinsic polycrystalline silicon layer (ipoly-Si); annealing the battery silicon wafer and depositing SiO2. x Mask, and through-grooving trenches formed in the first and / or second regions of the passivated contact by laser processing.

[0016] According to the manufacturing method disclosed herein, a dielectric layer and an intrinsic polycrystalline silicon layer i poly-Si are formed by low-pressure chemical vapor deposition (LPCVD) technology.

[0017] According to the manufacturing method disclosed herein, an oxygen- or carbon-containing phosphorus-doped amorphous silicon layer is formed by plasma-enhanced chemical vapor deposition (PECVD).

[0018] According to the manufacturing method disclosed herein, before forming the dielectric layer and the intrinsic polycrystalline silicon layer i poly-Si, the method further includes: performing a texturing treatment on the surface of the battery silicon wafer to form a velvety structure; performing boron diffusion on the surface of the battery silicon wafer to construct a PN junction; and removing the back side BSG and the diffusion layer.

[0019] According to the manufacturing method of this disclosure, after forming the penetrating trench, the process further includes: removing SiO from the laser region. x The process involves etching the surface of the silicon wafer, depositing an aluminum oxide passivation film and an anti-reflection film on the surface of the silicon wafer, and printing metal grid lines on the surface of the silicon wafer and sintering them to form electrodes.

[0020] This disclosure also provides a TOPCon solar cell module, the module comprising the TOPCon solar cell having a localized passivated contact structure as described above.

[0021] The TOPCon solar cell with localized passivation contact structure disclosed herein can reduce infrared free carrier absorption loss, improve passivation interface stability, alleviate film stress and the risk of film bursting, enhance local carrier collection capability, and is compatible with high-quality deposition methods such as LPCVD, with strong process flexibility and adjustability. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the localized passivation contact structure of the TOPCon solar cell according to the present disclosure.

[0023] Figure 2 This is a schematic diagram of the structure of the TOPCon solar cell according to this disclosure.

[0024] Figure 3 This is a flowchart of a method for manufacturing a TOPCon solar cell according to the present disclosure. Detailed Implementation

[0025] To enable those skilled in the art to better understand the technical solutions of this disclosure, the technical solutions of this disclosure will be described in detail below with reference to the accompanying drawings.

[0026] Exemplary embodiments will be described more fully below with reference to the accompanying drawings; however, these exemplary embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will enable those skilled in the art to fully understand the scope of this disclosure.

[0027] Where there is no conflict, the various embodiments of this disclosure and the features thereof in the embodiments may be combined with each other.

[0028] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0029] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. As used herein, the singular forms “a” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded.

[0030] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this disclosure, and will not be interpreted as having an idealized or overly formal meaning, unless expressly so defined herein.

[0031] Figure 1 This is a schematic diagram of the localized passivation contact structure of the TOPCon solar cell in this disclosure. Figure 1 The localized passivation contact structure in this disclosure is for illustrative purposes only, and is not limited to other localized passivation contact structures. Figure 1 The situation shown.

[0032] This disclosure provides a TOPCon solar cell with a localized passivated contact structure, comprising: a silicon wafer; a polycrystalline silicon stack layer disposed on the back side of the silicon wafer; a dielectric layer disposed between the polycrystalline silicon stack layer and the silicon wafer; and a trench extending along the thickness direction of the TOPCon solar cell and penetrating the polycrystalline silicon stack layer and the dielectric layer; the polycrystalline silicon stack layer is divided into at least one localized region, the localized region including a first region and a second region surrounding the first region; in the TOPCon solar cell, the trench is located in the first region and / or the second region.

[0033] In this disclosure, the first region and the second region are used to describe the surrounding relationship between two regions. For example, the region at the center is the first region, and the region surrounding the central region is the second region. More specifically, the first region and the second region are used to describe the surrounding relationship between the trench and the passivation contact structure. For example, if the trench is located in the central region and the passivation contact structure surrounds the trench, then the region where the trench is located is the first region, and the region where the passivation contact structure is located is the second region; conversely, if the passivation contact structure is located in the central region and the trench surrounds the passivation contact structure, then the region where the passivation contact structure is located is the first region, and the region where the trench is located is the second region.

[0034] This disclosure does not impose any special limitations on the shape of the trench and the passivation contact structure, as long as the above-mentioned surrounding and being surrounded relationship is satisfied.

[0035] In this disclosure, a polysilicon stack layer can be divided into one or more localized regions. When the polysilicon stack layer is divided into one localized region, it can be a first region with a trench at the center and a passivation contact structure surrounding the trench in a second region, or the passivation contact structure is located in the first region with the trench surrounding the passivation contact structure in the second region. When the polysilicon stack layer is divided into multiple localized regions, it can be that in all localized regions the trench is located in the first region and the passivation contact structure is located around the trench in the second region, or the passivation contact structure is located in the first region with the trench surrounding the passivation contact structure in the second region, or a localized region with the trench in the first region and the passivation contact structure surrounding the trench in the second region coexists with a localized region where the passivation contact structure is located in the first region and the trench surrounding the passivation contact structure in the second region. This disclosure does not impose any special limitations on this.

[0036] Combination Figure 1 The relationship of surrounding and being surrounded, as represented by the first and second zones, will be further explained. For example... Figure 1 As shown in (a), there is a case where a passivated contact structure surrounds the trench, i.e., the trench is located in the first region, and the passivated contact structure is located in the second region. Figure 1 As shown in (b), there are cases where the trench surrounds the passivation contact structure, i.e., in a localized region, the passivation contact structure is located in the first region and the trench is located in the second region; there are also cases where the passivation contact structure surrounds the trench, i.e., in another localized region, the trench is located in the first region and the passivation contact area is located in the second region. Figure 1 As shown in (c), there is a case where the trench surrounds the passivation contact structure, that is, the passivation contact structure is located in the first region and the trench is located in the second region.

[0037] According to the TOPCon solar cell disclosed herein, the polycrystalline silicon stack layer includes: the trench located in a localized region of the first region; and / or the polycrystalline silicon stack layer includes the trench located in a localized region of the second region.

[0038] According to the TOPCon solar cell of this disclosure, the trench is located in the second region and extends around the first region.

[0039] According to the TOPCon solar cell of this disclosure, in the localized region, the area ratio of the first region and the second region is X∈(0,1).

[0040] According to the TOPCon solar cell disclosed herein, in the localized region, the specific surface area values ​​of the first region and the second region are 1 to 1.3.

[0041] According to the TOPCon solar cell disclosed herein, the polycrystalline silicon stack layer contains poly-SiO₂. x Or poly-SiC.

[0042] When the polysilicon stack layer contains poly-SiO x At that time, poly-SiO x Deposition can be achieved using CO2, N2O, or O2.

[0043] When the polysilicon stack layer contains poly-SiC, CH4 is incorporated.

[0044] According to the TOPCon solar cell disclosed herein, the thickness of the polycrystalline silicon stack layer is 10-500 nm.

[0045] According to the TOPCon solar cell disclosed herein, the polycrystalline silicon stack layer contains poly-SiO₂. x The oxygen content is 0.05-20 at%.

[0046] According to the TOPCon solar cell of this disclosure, the first region and / or the second region are located in the non-metallic contact region of the TOPCon cell.

[0047] Figure 2 This is a schematic diagram of the structure of a TOPCon solar cell provided in this disclosure; Figure 3 A flowchart illustrating a method for manufacturing a TOPCon solar cell provided in this disclosure.

[0048] This disclosure provides a method for manufacturing a TOPCon solar cell with a localized passivated contact structure, referring to... Figure 2 , Figure 3 The method includes: S1. A dielectric layer and a polysilicon stack layer are formed on the back side of a battery silicon wafer. The polysilicon stack layer is divided into at least one localized region, which includes a first region and a second region surrounding the first region. S2. By laser processing, trenches are formed in the first region and / or the second region, extending along the thickness direction of the TOPCon solar cell and penetrating the polycrystalline silicon stack layer and the dielectric layer.

[0049] According to the manufacturing method of this disclosure, the manufacturing method further includes: An emitter layer, a surface passivation layer, and a front metal contact layer are sequentially formed on the front side of the battery silicon wafer. A back passivation layer and a back metal contact layer are sequentially formed on the side of the polycrystalline silicon stack away from the battery silicon wafer.

[0050] According to the manufacturing method of this disclosure, the manufacturing method includes: A dielectric layer and an intrinsic polycrystalline silicon layer (i-poly-Si) are formed on the backlight side of the battery silicon wafer; An oxygen- or carbon-containing phosphorus-doped amorphous silicon layer is formed on the intrinsic polycrystalline silicon layer i poly-Si; Annealing and SiO2 deposition are performed on the silicon wafers for battery use. x Mask, and Penetrating grooves are formed in the first and / or second regions of the passivated contact by laser processing.

[0051] According to the TOPCon solar cell manufacturing method disclosed herein, a dielectric layer and an intrinsic polycrystalline silicon layer (i poly-Si) are formed by low-pressure chemical vapor deposition (LPCVD) technology.

[0052] According to the TOPCon solar cell manufacturing method disclosed herein, an oxygen- or carbon-containing phosphorus-doped amorphous silicon layer is formed by plasma-enhanced chemical vapor deposition (PECVD).

[0053] According to the TOPCon solar cell manufacturing method disclosed herein, before forming the dielectric layer and the intrinsic polycrystalline silicon layer ipoly-Si, the method further includes: The surface of the battery silicon wafer is textured to form a velvety structure; Boron diffusion is performed on the surface of a battery silicon wafer to construct a PN junction; and Remove the backside BSG and diffusion layer.

[0054] According to the TOPCon solar cell manufacturing method disclosed herein, after forming the penetrating trench, the method further includes: Remove SiO from the laser region x And etch the surface of the battery silicon wafer; Depositing an aluminum oxide passivation film and an antireflection film on the surface of a battery silicon wafer; and Metal grid lines are printed on the surface of a silicon wafer and sintered to form electrodes.

[0055] According to one implementation scheme of this disclosure, combined with Figure 2 A method for manufacturing TOPCon solar cells with localized passivated contact structures includes: The surface of the battery silicon wafer is textured to form a velvety structure; Boron diffusion is performed on the surface of the battery silicon wafer to construct a PN junction; Remove the backside BSG and diffusion layer; A dielectric layer and an intrinsic polycrystalline silicon layer (i-poly-Si) are formed on the backlight side of the battery silicon wafer; An oxygen- or carbon-containing phosphorus-doped amorphous silicon layer is formed on the intrinsic polycrystalline silicon layer i poly-Si; Annealing and SiO2 deposition are performed on the silicon wafers for battery use. x Mask; A penetrating trench is formed in the first and / or second regions of the passivated contact by laser processing; Remove SiO from the laser region x And etch the surface of the battery silicon wafer; Depositing an aluminum oxide passivation film and an antireflection film on the surface of a battery silicon wafer; and Metal grid lines are printed on the surface of a silicon wafer and sintered to form electrodes.

[0056] In this disclosure, the back side BSG can be removed by a single-sided HF process, and the diffusion layer on the back side can be removed by alkaline polishing.

[0057] In this disclosure, a dielectric layer and an intrinsic polycrystalline silicon layer i poly-Si can be grown on the backlight side using low-pressure chemical vapor deposition (LPCVD) technology, thereby achieving high-quality crystallization and reducing hydrogen content.

[0058] In this disclosure, an oxygen- or carbon-containing phosphorus-doped amorphous silicon layer can be deposited on poly-Si using plasma-enhanced chemical vapor deposition (PECVD). The deposition of the oxygen- or phosphorus-doped amorphous silicon layer Poly-SiO... x It can be achieved using CO2, N2O, or O2. Alternatively, it can be achieved by depositing a carbon-doped phosphorus-doped amorphous silicon layer, Poly-SiC, by incorporating CH4.

[0059] This disclosure also provides a battery module including the above-described TOPCon solar cell with a localized passivated contact structure.

[0060] Compared with TOPCon cells employing a fully covered poly-Si layer, the TOPCon solar cell with a localized passivated contact structure disclosed in this invention has the following significant advantages in terms of structural design and performance optimization: 1) Reduce infrared free carrier absorption loss By designing a localized distribution structure of the first and second regions in the poly layer and introducing adjustment trenches (grooves) that penetrate the poly layer and the dielectric layer, the coverage area of ​​polysilicon is effectively reduced, thereby significantly reducing free carrier absorption (FCA) and improving long-wavelength optical response and short-circuit current density (Jsc) of the device.

[0061] 2) Improve the stability of the passivation interface Compared to the interface silicon oxide (SiOx) damage problem caused by high hydrogen content in the PECVD process, the structural design disclosed herein avoids the direct bombardment of the interface by hydrogen plasma, which helps to maintain the integrity of the tunneling oxide layer, thereby improving the interface passivation quality and open-circuit voltage (Voc).

[0062] 3) Mitigating membrane stress and reducing the risk of membrane rupture By locally depositing poly-Si or using an adjusted groove cutting structure, the stress generated during the deposition and annealing of polycrystalline silicon films can be released, significantly reducing the risk of film bursting or warping, and improving the mechanical reliability and mass production yield of the battery.

[0063] 4) Enhance local carrier collection capability This disclosure, by dividing the structure into a central first region and a surrounding second region, and selectively adjusting the position and size of the trenches, is beneficial to optimizing the current channel layout, improving the selective collection efficiency of charge carriers, and thus improving the fill factor (FF).

[0064] 5) Compatible with high-quality deposition methods such as LPCVD The structure disclosed herein is particularly suitable for LPCVD deposition of high-crystallization-quality i-poly-Si. Combined with the adjustment groove design, it can further reduce thickness absorption while taking into account passivation effect and optical performance.

[0065] 6) High degree of process flexibility and adjustability The position, shape, spot size, and laser energy of the adjustment slot can all be adjusted as needed to adapt to different battery designs and process windows, and it has good scalability and process integration compatibility.

[0066] To enable those skilled in the art to more clearly understand the technical solutions provided by the embodiments of this disclosure, the technical solutions provided by the embodiments of this disclosure will be described in detail below through specific embodiments: Example 1 The surface of the battery silicon wafer is textured to form a velvety structure; Boron diffusion is performed on the surface of the battery silicon wafer to construct a PN junction; The back side BSG is removed by a single-sided HF process, and the diffusion layer on the back side is removed by alkaline polishing. A dielectric layer and an intrinsic polycrystalline silicon layer (ipoly-Si) were grown on the backlight side using low-pressure chemical vapor deposition (LPCVD) technology. An oxygen-doped phosphorus-containing amorphous silicon layer, Poly-SiO, was deposited on i-poly-Si using plasma-enhanced chemical vapor deposition (PECVD). x Process gases include CO2, SiH4, H2, and PH3. Annealing and SiO2 deposition are performed on the silicon wafers for battery use. x Mask; A penetrating trench is formed in the first region of the passivated contact by laser processing; Remove SiO from the laser region x And etch the surface of the battery silicon wafer; Depositing an aluminum oxide passivation film and an antireflection film on the surface of a battery silicon wafer; and Metal grid lines are printed on the surface of a silicon wafer and sintered to form electrodes.

[0067] Example 2 The surface of the battery silicon wafer is textured to form a velvety structure; Boron diffusion is performed on the surface of the battery silicon wafer to construct a PN junction; The back side BSG is removed by a single-sided HF process, and the diffusion layer on the back side is removed by alkaline polishing. A dielectric layer and an intrinsic polycrystalline silicon layer (ipoly-Si) were grown on the backlight side using low-pressure chemical vapor deposition (LPCVD) technology. An oxygen-doped phosphorus-containing amorphous silicon layer, Poly-SiO, was deposited on i-poly-Si using plasma-enhanced chemical vapor deposition (PECVD). x Process gases include N2O, SiH4, H2, and PH3. Annealing and SiO2 deposition are performed on the silicon wafers for battery use. x Mask; A penetrating trench is formed in the first region of the passivated contact by laser processing; Remove SiO from the laser region x And etch the surface of the battery silicon wafer; Depositing an aluminum oxide passivation film and an antireflection film on the surface of a battery silicon wafer; and Metal grid lines are printed on the surface of a silicon wafer and sintered to form electrodes.

[0068] Example 3 The surface of the battery silicon wafer is textured to form a velvety structure; Boron diffusion is performed on the surface of the battery silicon wafer to construct a PN junction; The back side BSG is removed by a single-sided HF process, and the diffusion layer on the back side is removed by alkaline polishing. A dielectric layer and an intrinsic polycrystalline silicon layer (ipoly-Si) were grown on the backlight side using low-pressure chemical vapor deposition (LPCVD) technology. A carbon-phosphorus-doped amorphous silicon layer, Poly-SiC, was deposited on i-poly-Si using plasma-enhanced chemical vapor deposition (PECVD); the process gases included CH4, SiH4, H2, and PH3. Annealing and SiO2 deposition are performed on the silicon wafers for battery use. x Mask; A penetrating trench is formed in the first region of the passivated contact by laser processing; Remove SiO from the laser region x And etch the surface of the battery silicon wafer; Depositing an aluminum oxide passivation film and an antireflection film on the surface of a battery silicon wafer; and Metal grid lines are printed on the surface of a silicon wafer and sintered to form electrodes.

[0069] Comparative Example 1 The surface of the battery silicon wafer is textured to form a velvety structure; Boron diffusion is performed on the surface of the battery silicon wafer to construct a PN junction; The back side BSG is removed by a single-sided HF process, and the diffusion layer on the back side is removed by alkaline polishing. A dielectric layer and an intrinsic polycrystalline silicon layer (ipoly-Si) were grown on the backlight side using low-pressure chemical vapor deposition (LPCVD) technology. An oxygen-doped phosphorus-containing amorphous silicon layer, Poly-Si, was deposited on i-poly-Si using plasma-enhanced chemical vapor deposition (PECVD); the process gases included SiH4, H2, and PH3. Annealing and SiO2 deposition are performed on the silicon wafers for battery use. x Mask; Etching the surface of the battery silicon wafer; Depositing an aluminum oxide passivation film and an antireflection film on the surface of a battery silicon wafer; and Metal grid lines are printed on the surface of a silicon wafer and sintered to form electrodes.

[0070] The performance of the solar cells prepared in the above embodiments and comparative examples was tested, and the results are shown in Table 1 below.

[0071] Table 1 As can be seen from the data in Table 1 above, the TOPCon solar cells with localized passivated contact structures disclosed in this invention have significantly reduced IR loss and film bursting rate caused by free carrier absorption, while Jsc, Voc and module power have been improved.

[0072] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in connection with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in connection with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of this disclosure as set forth by the appended claims.

Claims

1. A TOPCon solar cell with a localized passivated contact structure, characterized in that, include: Battery silicon wafers; A polycrystalline silicon stack layer is disposed on the back side of the battery silicon wafer; A dielectric layer is disposed between the polycrystalline silicon stack layer and the battery silicon wafer; The trench extends along the thickness direction of the TOPCon solar cell and penetrates the polycrystalline silicon stack layer and the dielectric layer; The polycrystalline silicon stack layer is divided into at least one localized region, which includes a first region and a second region surrounding the first region; in the TOPCon solar cell, the trench is located in the first region and / or the second region.

2. The TOPCon solar cell according to claim 1, characterized in that, The polysilicon stack layer includes a localized region of the trench located in the first region; and / or The polysilicon stack layer includes the trench located in a localized region of the second region.

3. The TOPCon solar cell according to claim 2, characterized in that, The trench is located in the second region and extends around the first region.

4. The TOPCon solar cell according to any one of claims 1 to 3, characterized in that, In the localized region, the area ratio of the first region and the second region is X∈(0,1).

5. The TOPCon solar cell according to any one of claims 1 to 3, characterized in that, In the localized region, the specific surface area of ​​the first region and the second region is between 1 and 1.

3.

6. The TOPCon solar cell according to any one of claims 1 to 3, characterized in that, The polycrystalline silicon stack layer contains poly-SiO x Or poly-SiC.

7. The TOPCon solar cell according to any one of claims 1 to 3, characterized in that, The thickness of the polycrystalline silicon stack layer is 10-500 nm.

8. The TOPCon solar cell according to any one of claims 1 to 3, characterized in that, The first region and / or the second region are located in the non-metallic contact region of the TOPCon solar cell.

9. A method for manufacturing a TOPCon solar cell with a localized passivated contact structure, characterized in that, include: A dielectric layer and a polysilicon stack layer are formed on the back side of a battery silicon wafer. The polysilicon stack layer is divided into at least one localized region, which includes a first region and a second region surrounding the first region. By laser processing, trenches are formed in the first region and / or the second region, extending along the thickness direction of the TOPCon solar cell and penetrating the polycrystalline silicon stack layer and the dielectric layer.

10. The manufacturing method according to claim 9, characterized in that, The manufacturing method further includes: An emitter layer, a surface passivation layer, and a front metal contact layer are sequentially formed on the front side of the battery silicon wafer. A back passivation layer and a back metal contact layer are sequentially formed on the side of the polycrystalline silicon stack away from the battery silicon wafer.

11. A TOPCon solar cell module, characterized in that, The battery assembly includes a TOPCon solar cell with a localized passivated contact structure according to any one of claims 1 to 8.

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