Passivation contact structure, solar cell, module and system

Abstract

This application relates to the solar cell technology field and provides a passivation contact structure, a solar cell, a module, and a system. The passivation contact structure for a solar cell includes a silicon substrate and a first silicon oxide layer, a doped layer, a second silicon oxide layer, and a passivation layer sequentially disposed on the silicon substrate. The first silicon oxide layer includes a dilute region in a localized area, and the silicon oxide material content in the first silicon oxide layer is reduced in the dilute region. In this way, the dilute region in the first silicon oxide layer allows high-speed passage of H, effectively improving the H passivation effect and reducing the difficulty of heat treatment control.

Description

[Technical Field]

[0001] The present application is in the field of solar cell technology, and in particular relates to passivation contact structures, solar cells, modules and systems. [Background technology]

[0002] Solar cell power generation is a sustainable, clean energy source that can convert sunlight into electrical energy by utilizing the photovoltaic effect of a semiconductor pn junction, and the resulting electrical current is then conducted from the electrodes via conductive regions.

[0003] In related art, the conductive region of a solar cell includes a passivation contact structure. The passivation contact structure uses a tunnel layer to separate the doped layer from the silicon substrate, forming a structure in which the silicon substrate, tunnel layer, and doped layer are sequentially stacked. However, in the current passivation contact structure, the thickness of the silicon oxide layer prevents H from passing through quickly, resulting in a relatively low H passivation effect and significant challenges in heat treatment control.

[0004] Based on this, how to design the passivation contact structure to improve the H passivation effect and reduce the difficulty of heat treatment control is an issue that needs to be resolved as soon as possible. Summary of the Invention [Problem to be solved by the invention]

[0005] The present application aims to provide a passivation contact structure, and to solve the problem of how to design the passivation contact structure to improve the H passivation effect and reduce the difficulty of controlling the heat treatment. [Means for solving the problem]

[0006] The present invention is realized by providing a passivation contact structure for a solar cell, which includes: A silicon substrate; a first silicon oxide layer, a doped layer, a second silicon oxide layer, and a passivation layer sequentially disposed on the silicon substrate; A localized region of the first silicon oxide layer includes a lean region, and the silicon oxide material content of the first silicon oxide layer is reduced in the lean region.

[0007] Furthermore, the doping elements of the doped layer and the first silicon oxide layer are both Group 13 elements or Group 15 elements.

[0008] Furthermore, the Group 13 element is boron.

[0009] Furthermore, the Group 15 element is phosphorus.

[0010] Furthermore, the thickness of each of the first silicon oxide layer and the second silicon oxide layer is 3 nm or less.

[0011] Furthermore, the first silicon oxide layer has a thickness of 2.5 nm or less, and the second silicon oxide layer has a thickness of 2 nm or less.

[0012] Furthermore, the doped layer is a doped polysilicon layer.

[0013] Furthermore, the passivation layer is a combination of one or more of an oxide layer, a silicon carbide layer, and an amorphous silicon layer.

[0014] The present invention further provides a solar cell, which is a topcon cell or a back-contact cell, wherein the topcon cell or the back-contact cell comprises the passivation contact structure of the solar cell described above.

[0015] The present invention further provides a solar cell module, which includes the solar cell described above.

[0016] The present invention further provides a solar cell system, which includes the solar cell module described above. [Effects of the Invention]

[0017] In the passivation contact structure of the present embodiment, the first silicon oxide layer includes a dilute region in a localized area, in which the silicon oxide material content is reduced, and the remaining area is a non-dilute region, in which the silicon oxide content is lower than that of the non-dilute region. The dilute region in the first silicon oxide layer allows H to pass through at a high speed, effectively improving the H passivation effect and reducing the difficulty of heat treatment control. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a structural schematic diagram of a passivation contact structure of a solar cell provided in an embodiment of the present application; FIG. [Figure 2] 1 is an actual optical microscope image of a cross section of a passivation contact structure of a solar cell provided in an example of the present application. [Figure 3] 1 is a structural schematic diagram of a solar cell provided in an embodiment of the present application. [Explanation of symbols]

[0019] Solar cell 100, passivation contact structure 10, silicon substrate 101, first silicon oxide layer 11, dilute region 111, non-dilute region 112, doped layer 12, second silicon oxide layer 13, passivation layer 14. DETAILED DESCRIPTION OF THE INVENTION

[0020] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be described in more detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only used to interpret the present application, and are not intended to limit the present application.

[0021] In the present application, the first silicon oxide layer includes a dilute region in a local region, in which the silicon oxide material content is reduced in the dilute region, and the region other than the dilute region is a non-dilute region, in which the silicon oxide content in the dilute region is lower than that in the non-dilute region. The dilute region in the first silicon oxide layer allows H to pass through at a high speed, effectively improving the H passivation effect and reducing the difficulty of heat treatment control.

[0022] Example 1 Referring to FIG. 1, the passivation contact structure 10 of the solar cell according to the embodiment of the present application comprises: a silicon substrate 101; a first silicon oxide layer 11, a doped layer 12, a second silicon oxide layer 13 and a passivation layer 14, which are sequentially formed on a silicon substrate 101; The first silicon oxide layer 11 includes a dilute region 111 in a localized area, the dilute region 111 containing only a trace amount of silicon oxide.

[0023] The region of the first silicon oxide layer 11 other than the dilute region 111 can be defined as a non-dilute region 112. In the dilute region 111, the content of silicon oxide material is significantly reduced and becomes dispersed and sparse, allowing the material of the doped layer 12 to pass through the dilute region 111 and directly penetrate into the silicon substrate 101.

[0024] The silicon oxide content of the dilute region 111 is clearly lower than that of the non-dilute region 112. Under an optical microscope, the first silicon oxide layer 11 appears as a bright band about 1 nm wide, which is distinct from the materials on either side and is relatively bright, although in localized areas the brightness of the bright band appears slightly darker and the boundary between the materials on either side is relatively less clear, and this region corresponds to the dilute region 111.

[0025] In the solar cell passivation contact structure 10 of the embodiment of the present application, a first silicon oxide layer 11 includes a dilute region 111 in a local region thereof, in which the silicon oxide material content is reduced, and the remaining region is a non-dilute region 112, in which the silicon oxide content is lower than that of the non-dilute region 112. The dilute region 111 in the local region of the first silicon oxide layer 11 allows H to pass through at a high speed, effectively improving the H passivation effect and reducing the difficulty of heat treatment control.

[0026] Specifically, the number of the dilute regions 111 is plural. Furthermore, the dilute regions 111 exhibit a random discrete distribution. Furthermore, the areas of the dilute regions 111 may be the same or different, and the silicon oxide contents of the dilute regions 111 may be the same or different.

[0027] Specifically, there are a plurality of non-diluted regions 112. Furthermore, the plurality of non-diluted regions 112 exhibit a random discrete distribution. Furthermore, the areas of the plurality of non-diluted regions 112 may be the same or different, and the silicon oxide contents of the plurality of non-diluted regions 112 may be the same or different.

[0028] Figure 2 is an actual optical microscope image of a cross section of a passivation contact structure 10 of a solar cell. In Figure 2, the first silicon oxide layer 11 has a striped structure and extends from the left edge to the right edge of Figure 2. The luster of the first silicon oxide layer 11 is different from both the doped layer 12 and the silicon substrate 101, and the luster of the first silicon oxide layer 11 is brighter than the doped layer 12 and the silicon substrate 101. In addition, there is a difference between light and dark areas in the extending direction of the first silicon oxide layer 11, that is, the silicon oxide material of the first silicon oxide layer 11 is not distributed uniformly.

[0029] Specifically, areas of the first silicon oxide layer 11 with a high silicon oxide content are thicker and brighter in luster, i.e., non-dilute areas 112, and areas of the first silicon oxide layer 11 with a low silicon oxide content are very dilute in silicon oxide content and darker in luster, i.e., dilute areas 111.

[0030] Furthermore, since the dilute regions 111 and the non-dilute regions 112 are alternately distributed in the extension direction of the first silicon oxide layer 11, as shown in Figure 2, the first silicon oxide layer 11 forms a gloss change in which light and dark alternate in the extension direction.

[0031] As can be seen, the silicon oxide content of the dilute region 111 is so small that an optical microscope does not reveal any clear boundaries between the first silicon oxide layer 11, the silicon substrate 101, and the doped layer 12, and the doped layer 12 is in almost direct contact with the corresponding silicon substrate 101. In this way, the doping element of the doped layer 12 can penetrate into the silicon substrate 101 through the dilute region 111 of the first silicon oxide layer 11.

[0032] Specifically, the silicon substrate 101 includes opposing front and back surfaces, the front surface being the sun-facing, light-facing surface during normal operation and capable of receiving direct sunlight, and the back surface being away from the sun during normal operation and capable of receiving sunlight reflected off the ground when the solar cell is tilted toward the ground.

[0033] In this embodiment, the silicon substrate 101 is an N-type monocrystalline silicon wafer. It is understood that in other embodiments, the silicon substrate 101 may be other types of silicon wafers, such as a polycrystalline silicon wafer or a quasi-monocrystalline silicon wafer. The silicon substrate 101 may also be a P-type, and the silicon substrate 101 can be installed according to actual application needs, and is not particularly limited herein.

[0034] Specifically, an inter-diffusion layer may be formed between the silicon substrate 101 and the first silicon oxide layer 11. The inter-diffusion layer may include one or more of a doped crystalline silicon layer, a doped amorphous silicon layer, a doped polysilicon layer, a doped nanocrystalline silicon layer, a doped mixed crystal silicon layer, a doped silicon carbide layer, a doped silicon dioxide layer, a doped silicon carbide oxide layer, a doped silicon oxynitride layer, and a doped silicon oxynitride carbon layer. It should be understood that in other embodiments, the silicon substrate 101 and the first silicon oxide layer 11 may be in direct contact with each other and may not form an inter-diffusion layer.

[0035] Specifically, the number of the first silicon oxide layers 11 is 1. As can be understood, in other embodiments, the number of the first silicon oxide layers 11 may be 2, 3, 4, or other numbers.

[0036] In particular, the first silicon oxide layer 11 may be provided globally on the silicon substrate 101. It will be appreciated that in other embodiments the first silicon oxide layer 11 may be provided locally on the silicon substrate 101.

[0037] Specifically, the doped layer 12 includes one or more of a doped amorphous silicon layer, a doped polysilicon layer, a doped nanocrystalline silicon layer, a doped mixed crystal silicon layer, a doped silicon carbide layer, a doped silicon dioxide layer, a doped silicon carbide oxide layer, a doped silicon oxynitride layer, and a doped silicon oxycarbide layer.

[0038] Furthermore, when the doped layer 12 includes multiple types of the above-mentioned film layers, the multiple types of film layers may be mixed together or stacked sequentially. Some types of film layers may be mixed, and the remaining types of film layers may be stacked sequentially. Multiple types of film layers in some regions may be mixed, and the remaining types of film layers may be stacked sequentially. The specific form of the doped layer 12 is not limited here.

[0039] Furthermore, the doped layer 12 may include multiple doped films stacked in sequence, with the refractive index of each adjacent doped film being different. In this manner, the two adjacent doped films may form a refractive index gradient, thereby achieving gradient extinction and enhancing the absorption of light in the solar cell, which is advantageous for improving the photoelectric conversion efficiency. It should be understood that in other embodiments, the doped layer 12 may include multiple doped films stacked in sequence, with the refractive index of each adjacent doped film being the same.

[0040] Specifically, the doping polarity of the doped layer 12 may be the same as or different from that of the silicon substrate 101. In other words, the doping polarity of the doped layer 12 and the doping polarity of the silicon substrate 101 may both be N-type or both be P-type. The doping polarity of the doped layer 12 may be N-type and the doping polarity of the silicon substrate 101 may be P-type. The doping polarity of the doped layer 12 may be P-type and the doping polarity of the silicon substrate 101 may be N-type.

[0041] In particular, the doped layer 12 may be provided globally on the first silicon oxide layer 11. It will be appreciated that in other embodiments the doped layer 12 may be provided locally on the first silicon oxide layer 11.

[0042] Specifically, the second silicon oxide layer 13 may have the same structure as the first silicon oxide layer 11. The second silicon oxide layer 13 may be denser and thicker than the first silicon oxide layer 11.

[0043] Specifically, the thickness of the second silicon oxide layer 13 is greater than 0.3 nm and less than 0.5 nm, such as 0.31 nm, 0.32 nm, 0.38 nm, 0.4 nm, 0.45 nm, or 0.49 nm. As can be seen, the second silicon oxide layer 13 can form dense semi-coherent grain boundaries with the doped layer 12. External metals can easily form short circuits through the semi-coherent grain boundaries and diffuse into the silicon substrate 101, ultimately resulting in a degradation of electrical performance or PID failure. However, a second silicon oxide layer 13 with a thickness greater than 0.3 nm can effectively prevent the diffusion of metal impurities. At the same time, a second silicon oxide layer 13 with a thickness less than 5 nm allows H ions in the outer passivation layer 14 to quickly penetrate the doped layer 12, the interface between the doped layer 12 and the silicon substrate 101, and the silicon substrate 101 during heat treatments such as sintering and annealing, thereby providing effective H passivation.

[0044] Specifically, the number of the second silicon oxide layers 13 is 1. As can be understood, in other embodiments, the number of the second silicon oxide layers 13 may be 2, 3, 4, or other numbers.

[0045] In particular, the second silicon oxide layer 13 may be provided globally on the doped layer 12. It will be appreciated that in other embodiments the second silicon oxide layer 13 may be provided locally on the doped layer 12.

[0046] Specifically, the passivation layer 14 includes at least one of a silicon oxide layer, a silicon nitride layer, and a silicon oxynitride layer, thereby achieving surface passivation of the solar cell.

[0047] Furthermore, the number of layers of the passivation layer 14 may be one, two, three, or any other number.

[0048] Additionally, slots may be formed in the passivation layer 14. In this way, electrodes may pass through the passivation layer 14 and the second silicon oxide layer 13 through the slots to contact the doped layer 12 and thereby conduct the current generated by the solar cell.

[0049] Example 2 In some alternative embodiments, the doping elements of the doped layer 12 and the first silicon oxide layer 11 are both Group 13 or Group 15 elements.

[0050] In this way, by using a Group 13 element or a Group 15 element, the doped layer 12 and the first silicon oxide layer 11 form a P-type doped region or an N-type doped region, thereby forming a PN junction in the silicon substrate 101.

[0051] Specifically, the Group 13 elements include boron, aluminum, gallium, indium, and thallium. The doping elements of the doped layer 12 and the first silicon oxide layer 11 may be one or more of boron, aluminum, gallium, indium, and thallium.

[0052] Specifically, the Group 15 elements include nitrogen, phosphorus, arsenic, antimony, and bismuth. The doping elements of the doped layer 12 and the first silicon oxide layer 11 may be one or more of nitrogen, phosphorus, arsenic, antimony, and bismuth.

[0053] Example 3 In some alternative embodiments, the group 13 element is boron, which causes the doped layer 12 and the first silicon oxide layer 11 to form a P-type doped region. Of course, in other embodiments, the group 13 element may be other, which will not be described here in detail.

[0054] Example 4 In some alternative embodiments, the Group 15 element is phosphorus, which causes the doped layer 12 and the first silicon oxide layer 11 to form an N-type doped region. Of course, in other embodiments, the Group 15 element may be other elements, which will not be described here.

[0055] Example 5 In some alternative embodiments, the thickness of the first silicon oxide layer 11 and the second silicon oxide layer 13 are both 3 nm or less, i.e., the thickness of the first silicon oxide layer 11 is 3 nm or less, and the thickness of the second silicon oxide layer 13 is also 3 nm or less.

[0056] In this way, by setting the thicknesses of the first silicon oxide layer 11 and the second silicon oxide layer 13 to be within appropriate ranges, the gettering and conductive effects of the first silicon oxide layer 11 are improved, and the effects of the second silicon oxide layer 13 in preventing the diffusion of metal impurities and allowing H ions to pass through quickly are improved.

[0057] Specifically, the thickness of the first silicon oxide layer 11 is, for example, 2.9 nm, 2.8 nm, 2.5 nm, 2.2 nm, 2 nm, 1.5 nm, 1 nm, 0.8 nm, or 0.5 nm.

[0058] Specifically, the thickness of the second silicon oxide layer 13 is, for example, 0.5 nm, 0.8 nm, 1 nm, 1.2 nm, 1.5 nm, 2 nm, 2.5 nm, 2.8 nm, or 3 nm.

[0059] Example 6 In some alternative embodiments, the thickness of the first silicon oxide layer 11 is 2.5 nm or less, and the thickness of the second silicon oxide layer 13 is 2 nm or less.

[0060] In this way, by setting the thicknesses of the first silicon oxide layer 11 and the second silicon oxide layer 13 to more appropriate ranges, the gettering and conductive effects of the first silicon oxide layer 11 are further improved, and the effect of the second silicon oxide layer 13 in preventing the diffusion of metal impurities and allowing H ions to pass through quickly is further improved.

[0061] Specifically, the thickness of the first silicon oxide layer 11 is, for example, 0.5 nm, 0.8 nm, 1 nm, 1.2 nm, 1.5 nm, 1.8 nm, 2 nm, 2.3 nm, or 2.5 nm.

[0062] Specifically, the thickness of the second silicon oxide layer 13 is, for example, 0.5 nm, 1 nm, 1.2 nm, 1.5 nm, 1.8 nm, 1.9 nm, or 2 nm.

[0063] Specifically, 80% or more of the silicon oxide is concentrated within a thickness region of 0.5 nm to 2.5 nm in the first silicon oxide layer 11. The silicon oxide content is high in some regions, and the first silicon oxide layer 11 exhibits a high thickness of greater than 2.5 mm. That is, the thickness of the first silicon oxide layer 11 in the diluted region 111 is 0.5 nm to 2.5 nm, and the thickness of the first silicon oxide layer 11 in the non-diluted region 112 is greater than 2.5 mm.

[0064] Example 7 In some alternative embodiments, doped layer 12 is a doped polysilicon layer.

[0065] In this way, it is easier to dope the intrinsic polysilicon layer into the doped polysilicon layer than the first silicon oxide layer 11, and the doping of the intrinsic polysilicon layer can be prevented from affecting the first silicon oxide layer 11, ensuring the normal fabrication and function of the first silicon oxide layer 11 and the doped polysilicon layer. In addition, the doped polysilicon layer can prevent the diffusion of metal impurities and allows H ions in the passivation layer 14 to quickly penetrate and reach the silicon substrate 101 during heat treatments such as sintering and annealing, thereby forming effective H passivation.

[0066] In the example of FIG. 2, the brightness of the doped layer 12 is interposed between the first silicon oxide layer 11 and the silicon substrate 101. Specifically, the doped layer 12 is darker than the first silicon oxide layer 11 and brighter than the silicon substrate 101. The doped layer 12 is formed into blocks of different brightnesses, and the blocks of different brightnesses have different doping concentrations. The brightness difference between the doped layer 12 and the dilute region 111 of the first silicon oxide layer 11 is large, forming a clear boundary line. The brightness difference between the doped layer 12 and the non-dilute region 112 of the first silicon oxide layer 11 is small, but the boundary line is still faintly visible.

[0067] Example 8 In some alternative embodiments, passivation layer 14 is a combination of one or more of an oxide layer, a silicon carbide layer, and an amorphous silicon layer.

[0068] In this way, a good passivation effect is achieved.

[0069] For example, the passivation layer 14 may be an oxide layer of a single material, or may be a combination of oxide layers of multiple materials and amorphous silicon layers, or may be a combination of multiple layers of amorphous silicon with different refractive indices of a single material. The passivation layer 14 may also be a silicon oxynitride layer, a silicon nitride layer, etc. It should be understood that the specific structural configuration of the passivation layer 14 includes, but is not limited to, the several methods described above, and corresponding configurations for the passivation layer 14 can be made according to actual application needs, and are not particularly limited herein.

[0070] Furthermore, the thickness of the passivation layer 14 is 0.5 to 10 nm. Preferably, the thickness of the passivation layer 14 is 0.8 to 2 nm. It should be understood that the thickness of the passivation layer 14 can be set to the same thickness as the tunnel layer in the prior art, or can be set to a thickness thicker than the conventional tunnel layer thickness, and is set according to actual usage needs and is not particularly limited herein.

[0071] Preferably, the passivation layer 14 is an oxide layer and a silicon carbide layer arranged sequentially outward from the second silicon oxide layer 13. Furthermore, the oxide layer is preferably one or more of a silicon oxide layer and an aluminum oxide layer. Furthermore, the silicon carbide layer includes a hydrogenated silicon carbide layer, in which hydrogen in the hydrogenated silicon carbide layer can enter the silicon substrate 101 through a diffusion mechanism and thermal effect, neutralizing dangling bonds on the back surface of the silicon substrate 101 and passivating defects in the silicon substrate 101, thereby transferring energy bands in the forbidden band to the valence band or conduction band, and improving the probability of carriers entering the second silicon oxide layer 13 through the passivation layer 14.

[0072] Example 9 Referring to FIG. 3, the solar cell 100 of the present embodiment is a topcon cell or a back-contact cell, and the topcon cell or the back-contact cell includes the passivation contact structure 10 of the solar cell 100 described in any one of Examples 1 to 8.

[0073] In the solar cell 100 of the embodiment of the present application, the first silicon oxide layer 11 includes a dilute region 111 in a local region thereof, in which the silicon oxide material content is reduced in the dilute region 111, and the region other than the dilute region 111 is a non-dilute region 112, in which the silicon oxide content in the dilute region 111 is lower than that in the non-dilute region 112. The dilute region in the first silicon oxide layer 11 allows H to pass through at a high speed, effectively improving the H passivation effect and reducing the difficulty of heat treatment control.

[0074] Specifically, when the solar cell 100 is a back-contact cell, the conductive regions of the two polarities P and N are spaced apart on one side of the back-contact cell. When the solar cell 100 is a double-sided contact cell, the conductive regions of the two polarities P and N are respectively provided on both sides of the back-contact cell.

[0075] Furthermore, both conductive regions of two polarities may be the passivation contact structure 10 of the solar cell 100 described in any one of Examples 1 to 8. The P-type conductive region may be the passivation contact structure 10 of the solar cell 100 described in any one of Examples 1 to 8, and the N-type conductive region may not be the passivation contact structure 10 of the solar cell 100 described in any one of Examples 1 to 8. The N-type conductive region may be the passivation contact structure 10 of the solar cell 100 described in any one of Examples 1 to 8, and the P-type conductive region may not be the passivation contact structure 10 of the solar cell 100 described in any one of Examples 1 to 8.

[0076] Furthermore, the solar cell 100 includes two electrodes of P and N polarities, i.e., a first electrode 191 and a second electrode 192 in FIG. 3, which are connected to the silicon substrate 101 via conductive regions of the two polarities, P and N, respectively.

[0077] Example 10 The solar cell module of the present embodiment includes the solar cell 100 of Example 9.

[0078] In the solar cell module of the embodiment of the present application, a local region of the first silicon oxide layer 11 includes a dilute region 111, in which the silicon oxide material content is reduced in the dilute region 111, and the region other than the dilute region 111 is a non-dilute region 112, in which the silicon oxide content in the dilute region 111 is lower than that in the non-dilute region 112. The dilute region in the first silicon oxide layer 11 allows H to pass through at a high speed, effectively improving the H passivation effect and reducing the difficulty of heat treatment control.

[0079] In this embodiment, multiple solar cells 100 in the solar cell module can be connected in series to form a battery string, thereby realizing a serial bus output of current. For example, the serial connection of the battery cells can be realized by installing a welding strip (bus bar, interconnect bar), a conductive back sheet, etc.

[0080] It should be understood that in this embodiment, the solar cell module may further include a metal frame, a backsheet, a PV glass, and an adhesive film. The adhesive film may be filled between the front and back surfaces of the solar cell 100 and the PV glass, between adjacent battery cells, etc. As a filler, it may be a transparent colloid with good light transmittance and aging resistance. For example, the adhesive film may be an EVA adhesive film or a POE adhesive film. The specific selection may be made according to actual circumstances and is not limited here.

[0081] PV glass can be coated on the adhesive film on the front of the solar cell 100, and the PV glass can be white plate glass, which has high light transmittance, high transparency, and excellent physical, mechanical, and optical properties, for example, the light transmittance of white plate glass can reach 92% or more, which can protect the solar cell 100 while minimizing the impact on the efficiency of the solar cell 100. At the same time, the adhesive film can bond the PV glass and the solar cell 100, and the presence of the adhesive film can provide sealing, insulation, and waterproof and moisture-proofing for the solar cell 100.

[0082] The backsheet can be attached to the adhesive film on the back of the solar cell 100, and can provide protection and support for the solar cell 100, and has reliable insulation, water-stopping, and aging resistance. There are several options for the backsheet, and it can usually be tempered glass, organic glass, aluminum alloy TPT composite adhesive film, etc., which can be installed according to specific circumstances and are not limited here. The entire structure consisting of the backsheet, solar cell 100, adhesive film, and PV glass can be installed in a metal frame, and the metal frame serves as the main external support structure for the entire solar cell module and can provide stable support and mounting for the solar cell module. For example, the solar cell module can be mounted in a desired position using the metal frame.

[0083] Example 11 The solar cell system of the present embodiment includes the solar cell module of the tenth embodiment.

[0084] In the solar cell system of the embodiment of the present application, a local region of the first silicon oxide layer 11 includes a dilute region 111, in which the silicon oxide material content is reduced, and the region other than the dilute region 111 is a non-dilute region 112, in which the silicon oxide content in the dilute region 111 is lower than that in the non-dilute region 112. The dilute region in the first silicon oxide layer 11 allows H to pass through at a high speed, effectively improving the H passivation effect and reducing the difficulty of heat treatment control.

[0085] In this embodiment, the solar cell system can be applied to solar power plants, such as ground power plants, rooftop power plants, and water power plants, and can also be applied to equipment or devices that use solar energy to generate electricity, such as user solar energy power supplies, solar energy street lights, solar energy vehicles, and solar energy buildings. It should be understood that the application scenarios of the solar cell system are not limited thereto, and that the solar cell system can be applied to all fields that require solar energy to generate electricity. Taking a solar power generation system network as an example, the solar cell system can include a solar array, a bus box, and an inverter. The solar array can be an array combination of multiple solar cell modules. For example, multiple solar cell modules can form multiple solar arrays. The solar arrays are connected to a bus box, and the bus box can bus the current generated by the solar array. The bused current is converted into AC power required for the utility power network via an inverter, and then accessed by the utility power network to realize solar power supply.

[0086] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application should be included within the scope of protection of the present application. In addition, the specific features, structures, materials, or characteristics described in each embodiment or example of the present application can be combined in any one or more embodiments or examples in an appropriate manner.

Claims

1. A passivation contact structure for a solar cell, comprising: A silicon substrate; a first silicon oxide layer, a doped layer, a second silicon oxide layer, and a passivation layer sequentially disposed on the silicon substrate; 1. A passivation contact structure for a solar cell, characterized in that a localized region of the first silicon oxide layer includes a dilute region, and a silicon oxide material content in the first silicon oxide layer is reduced in the dilute region.

2. 2. The passivation contact structure of claim 1, wherein the doped layer and the first silicon oxide layer are doped with elements selected from the group 13 and the group 15 of the elements.

3. 3. The passivation contact structure for a solar cell according to claim 2, wherein the Group 13 element is boron.

4. 3. The passivation contact structure for a solar cell according to claim 2, wherein the Group 15 element is phosphorus.

5. 2. The passivation contact structure for a solar cell according to claim 1, wherein the thickness of each of the first silicon oxide layer and the second silicon oxide layer is 3 nm or less.

6. 6. The passivation contact structure of claim 5, wherein the first silicon oxide layer has a thickness of 2.5 nm or less, and the second silicon oxide layer has a thickness of 2 nm or less.

7. 2. The passivation contact structure of claim 1, wherein the doped layer is a doped polysilicon layer.

8. 2. The passivation contact structure of claim 1, wherein the passivation layer is one or a combination of a silicon oxide layer, a silicon carbide layer, and an amorphous silicon layer.

9. A solar cell, characterized in that the solar cell is a top-contact cell or a back-contact cell, and the top-contact cell or the back-contact cell includes the passivation contact structure of a solar cell according to any one of claims 1 to 8.

10. A solar cell module comprising the solar cell according to claim 9.

11. A solar cell system comprising the solar cell module according to claim 10.

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