Solar cell and manufacturing method therefor, and photovoltaic module

Abstract

The present invention relates to a solar cell and a manufacturing method therefor, and a photovoltaic module. The solar cell comprises: a substrate, where the substrate comprises a first surface; a passivation contact structure, where the passivation contact structure is disposed on a portion of the first surface; and a first electrode, where the first electrode is disposed on the side of the passivation contact structure facing away from the substrate, and is electrically connected to the passivation contact structure, a portion of the passivation contact structure being provided with a marker portion.

Description

Solar cells and their manufacturing methods, photovoltaic modules

[0001] Related applications

[0002] This application claims priority to Chinese patent application filed on October 21, 2024, application number 202411465985.5, entitled "Solar Cells and Methods of Manufacturing Thereof, Photovoltaic Modules", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to the field of photovoltaic technology, and in particular to a solar cell and its manufacturing method, and a photovoltaic module. Background Technology

[0004] In order to reduce recombination rate, extend minority carrier lifetime and improve the photoelectric conversion efficiency of solar cells, related technologies generally passivate the substrate and form a passivation contact layer on the substrate surface to reduce the recombination of surface carriers, thereby reducing the impact of defects inside the substrate.

[0005] However, most passivated contact structures exhibit significant parasitic absorption of incident light, leading to a decrease in the photocurrent generated by the solar cell and affecting its efficiency. To address this issue, patterned passivated contact structures are typically used to reduce parasitic absorption of incident light by minimizing the area of ​​the passivated contact structure. Solar cells with patterned passivated contact structures have a relatively complex manufacturing process and require higher precision. They often necessitate using markers on the cell surface as positioning references to ensure accurate printing of the electrode paste onto the patterned passivated contact structure. Summary of the Invention

[0006] Therefore, it is necessary to provide a solar cell, its manufacturing method, and a photovoltaic module.

[0007] The first aspect of this application provides a solar cell, comprising:

[0008] Substrate, the substrate includes a first surface;

[0009] Passivated contact structure, passivated contact structure disposed on a portion of the surface of the first surface; and

[0010] The first electrode is disposed on the side of the passivation contact structure away from the substrate and is electrically connected to the passivation contact structure.

[0011] Some of the passivated contact structures are provided with markings.

[0012] In one embodiment, the marking portion does not overlap with the orthographic projection of the first electrode on the first surface.

[0013] In one embodiment, the marking portion is configured to serve as a positioning reference during the formation of the first electrode.

[0014] In one embodiment, the first electrode includes a plurality of first sub-electrodes and a plurality of second sub-electrodes, the plurality of first sub-electrodes being spaced apart along a first direction, and each first sub-electrode being connected to at least two second sub-electrodes being spaced apart along a second direction.

[0015] The marking portion is at least partially located between two adjacent second sub-electrodes, and the two adjacent second sub-electrodes are connected to the same first sub-electrode; the first direction and the second direction intersect and are both perpendicular to the thickness direction of the solar cell.

[0016] In one embodiment, the marking portion and two second sub-electrodes adjacent to the marking portion are spaced apart.

[0017] In one embodiment, the orthographic projection of the marking portion and at least one second sub-electrode adjacent to the marking portion onto the first surface contacts or overlaps.

[0018] In one embodiment, the first surface includes one or more first regions and one or more passivated contact regions;

[0019] The passivated contact structure includes one or more first passivated contact structures and one or more second passivated contact structures;

[0020] The first passivation contact structure and the second passivation contact structure are respectively disposed in the corresponding passivation contact area, and the orthographic projections of the second passivation contact structure and the first passivation contact structure on the first surface do not overlap.

[0021] The first electrode is disposed on the side of the first passivation contact structure away from the substrate; the marking portion is disposed on the second passivation contact structure.

[0022] In one embodiment, the contour edges of the plurality of first passivated contact structures respectively define a plurality of accommodating regions;

[0023] Each second passivated contact structure is located within its corresponding accommodating region.

[0024] In one embodiment, a plurality of first passivated contact structures are arranged spaced apart from each other;

[0025] Each first passivated contact structure includes a first contact area and a plurality of second contact areas extending from the first contact area in a direction away from the first contact area;

[0026] An accommodating area is formed between two adjacent second contact areas, and the two adjacent second contact areas are connected to the same first contact area.

[0027] In one embodiment, multiple first contact areas of multiple first passivation contact structures are arranged at intervals along a first direction, and multiple second contact areas connected to the same first contact area are arranged at intervals along a second direction. The first direction and the second direction intersect and are both perpendicular to the thickness direction of the solar cell.

[0028] In one embodiment, the first electrode includes a plurality of first sub-electrodes and a plurality of second sub-electrodes, each first sub-electrode being connected to at least two second sub-electrodes spaced apart in a second direction; the plurality of first sub-electrodes are disposed one-to-one on the side surface of the first contact area away from the substrate, and the plurality of second sub-electrodes are disposed one-to-one on the side surface of the second contact area connected to the first contact area away from the substrate.

[0029] The second passivated contact structure is located between two adjacent second sub-electrodes in the second direction, and the two adjacent second sub-electrodes are connected to the same first sub-electrode.

[0030] In one embodiment, each first passivated contact structure includes a plurality of spaced-apart third contact areas, with a receiving area disposed between two adjacent third contact areas;

[0031] The first electrode includes multiple third sub-electrodes, which are disposed one-to-one in the third contact area.

[0032] In one embodiment, at least one of the first passivation contact structure and the second passivation contact structure includes a first tunneling oxide layer and a first polysilicon doped conductive layer stacked on each other, wherein the first tunneling oxide layer is disposed on the first surface.

[0033] In one embodiment, the first passivated contact structure and the second passivated contact structure are arranged at intervals.

[0034] In one embodiment, the marking portion is spaced from the edge of the corresponding second passivated contact structure.

[0035] In one embodiment, the number of marking portions is multiple;

[0036] Multiple markings are used to locate the geometric center of the solar cell.

[0037] In one embodiment, the marking portion includes a first groove;

[0038] The first groove extends into the interior of the second passivated contact structure; or

[0039] The first groove extends to and terminates at the boundary between the second passivated contact structure and the first surface in the passivated contact area along the thickness direction of the solar cell; or

[0040] The first groove extends into the interior of the substrate corresponding to the passivation contact area.

[0041] In one embodiment, when the first groove extends into the substrate corresponding to the passivation contact region, the maximum gap D1 between the bottom wall of the first groove and the first surface of the passivation contact region satisfies: D1 > 1 μm.

[0042] In one embodiment, the bottom wall of the first groove includes a central region and an over-etched region adjacent to the edge of the central region;

[0043] The setting height of the etched region relative to the second surface of the substrate is lower than the setting height of the central region relative to the second surface;

[0044] The second surface is positioned opposite to the first surface.

[0045] In one embodiment, the width dimension W1 of the first groove satisfies: W1 < 100 μm.

[0046] In one embodiment, the marking portion further includes a transition processing area located between the groove edge of the first groove and the edge of the adjacent second passivated contact structure;

[0047] The reflectivity of the surface of the transition treatment region facing away from the substrate is greater than the reflectivity of the surface of the second passivated contact structure facing away from the substrate.

[0048] In one embodiment, the surface of the transition processing region away from the substrate is configured with multiple protrusions;

[0049] The height of the tips of the multiple protrusions relative to the second surface of the substrate gradually increases from one side of the groove edge of the first groove to the edge of the adjacent second passivated contact structure.

[0050] In one embodiment, the roughness of the surface of the transition processing region facing away from the substrate is less than the roughness of the surface of the second passivation contact structure facing away from the substrate.

[0051] In one embodiment, the transition processing zone includes a melt of the first material and the second material;

[0052] Wherein, the first material is the passivation contact material contained in the second passivation contact structure, and the second material is the substrate material contained in the substrate.

[0053] In one embodiment, the surface of the transition treatment region away from the substrate is lower than the surface of the second passivation contact structure by D0, where D0 satisfies: 50nm < D0 < 1μm.

[0054] In one embodiment, the dimension W2 of the marking portion along the width direction of the first groove satisfies: W2 < 120 μm.

[0055] In one embodiment, a third structure is further provided on the side surface of the second passivated contact structure facing away from the substrate;

[0056] The third structure is arranged around the marking portion, and the reflectivity of the surface of the third structure facing away from the substrate is greater than the reflectivity of the surface of the second passivated contact structure facing away from the substrate.

[0057] In one embodiment, the reflectivity of the surface of the third structure facing away from the substrate, the reflectivity of the surface of the transition processing region facing away from the substrate, and the reflectivity of the bottom wall of the first groove increase sequentially.

[0058] In one embodiment, the outer contour of the first groove is circular or annular; or...

[0059] The first groove includes at least two intersecting groove segments.

[0060] In one embodiment, the first surface includes a plurality of first regions and at least one passivated contact region;

[0061] Each of the first regions, at least in part, is constructed to be defined by a passivated contact region surrounding it.

[0062] In one embodiment, the first region is closer to the second surface of the substrate than the passivation contact region, and the second surface is disposed opposite to the first surface.

[0063] In one embodiment, the discontinuity D2 between the first surface of the first region and the first surface of the passivation contact region satisfies: D2 > 1 μm.

[0064] In one embodiment, the marking portion includes a first groove, and the discontinuity D1 and D2 between the bottom wall of the first groove and the first surface of the passivation contact area satisfy: D2≤D1.

[0065] In one embodiment, the solar cell includes multiple sides, at least some of which are cut surfaces.

[0066] A second aspect of this application provides a method for manufacturing a solar cell, comprising:

[0067] A substrate is provided, the substrate including a substrate, a passivation contact material layer and a dielectric layer sequentially stacked on a first surface of the substrate, the first surface of the substrate including a first region and a passivation contact region;

[0068] The portion of the dielectric layer covering the first region is patterned, and a marking structure is formed at the location where the dielectric layer covers the passivation contact region, the marking structure extending at least to the passivation contact material layer;

[0069] Using the portion of the dielectric layer that has been patterned and formed with a marking structure covering the passivation contact area as a mask, the portion of the passivation contact material layer located in the first region is removed, and the dielectric layer is removed to form a marking part of the marking structure.

[0070] A first passivation layer is formed on the side of the passivation contact material layer away from the substrate. Using a marker as a positioning reference, a first electrode is formed at the position where the first passivation layer covers the passivation contact area.

[0071] In one embodiment, the step of forming a marking structure at the location where the dielectric layer covers the passivation contact region specifically includes:

[0072] The first laser is used to locally scan the area covered by the dielectric layer in the passivated contact region to form a marking structure.

[0073] In one embodiment, the step of patterning the portion of the dielectric layer covering the first region specifically includes:

[0074] The second laser is used to scan the entire area where the dielectric layer covers the first region.

[0075] The second laser has a larger spot size than the first laser, and the second laser has a higher laser power than the first laser.

[0076] In one embodiment, the diameter of the first laser spot is less than 120 μm and the power is 10 W-100 W.

[0077] The second laser has a spot diameter greater than 150μm and a power of 40W-200W.

[0078] In one embodiment, the step of using a first laser to locally scan the location where the dielectric layer covers the passivated contact area specifically includes:

[0079] A first laser is used to reciprocately scan the dielectric layer along a first path and then along a second path to form a marking structure with an intersecting outer contour on the dielectric layer, wherein the first and second paths intersect and are both straight lines; or

[0080] The dielectric layer is scanned along a ring-shaped path using a first laser to form a marking structure with a ring-shaped outer contour; or

[0081] The first laser is used to scan the dielectric layer along a circular region to form a marker structure with a circular outer contour.

[0082] In one embodiment, the marking portion includes a first groove;

[0083] In the step of using the portion of the dielectric layer that has been patterned and formed with a marking structure, covering the passivation contact area, as a mask, removing the portion of the passivation contact material layer located in the first region, and then removing the dielectric layer to form the marking portion of the marking structure:

[0084] The passivation contact material layer in the first region is removed by wet etching, and the dielectric layer is also removed to form a first groove in the passivation contact material layer covering the passivation contact region.

[0085] In one embodiment, the marking structure further includes a transition processing area located at the edge of the groove of the first groove; the energy intensity at the central local region of the first laser spot is greater than the energy intensity at the edge region of the spot;

[0086] After wet etching, in the passivation contact material layer, in the area treated by the central local area, a first groove is formed in a part of the location, and another part of the location and the area treated by the edge area form a transition treatment area. The transition treatment area includes the dielectric layer, the passivation contact material layer and the molten material included in the substrate.

[0087] In one embodiment, after wet etching, a third structure is formed around the marking structure, and the reflectivity of the surface of the third structure away from the substrate is greater than the reflectivity of the surface of the passivation contact material layer away from the substrate.

[0088] In one embodiment, in the step of removing the portion of the passivation contact material layer located in the first region by using the portion of the dielectric layer that has been patterned and formed with a marked structure covering the passivation contact region as a mask, the first region of the substrate is also etched inward in the substrate thickness direction by a portion of the thickness.

[0089] In one embodiment, the step of patterning the portion of the dielectric layer covering the first region includes:

[0090] The portion of the dielectric layer covering the first region is modified;

[0091] The step of removing the portion of the passivation contact material layer located in the first region from the patterned and marked dielectric layer covering the passivation contact region specifically includes:

[0092] Wet etching is used to remove the portion of the dielectric layer covering the first region and the portion of the passivation contact material layer located in the first region.

[0093] In one embodiment, the step of patterning the portion of the dielectric layer covering the first region includes:

[0094] Remove the portion of the dielectric layer that covers the first region;

[0095] The step of removing the portion of the passivation contact material layer located in the first region from the patterned and marked dielectric layer covering the passivation contact region specifically includes:

[0096] The portion of the passivated contact material layer located in the first region is removed by wet etching.

[0097] In one embodiment, the method further includes the step of cutting the solar cell along its thickness into multiple solar cell substrates, wherein the number of marking portions in the partially cut solar cell substrates is 0, and the number of marking portions in the partially cut solar cell substrates is 1 or more.

[0098] The third aspect of this application provides a solar cell manufactured using the solar cell manufacturing method described above.

[0099] A fourth aspect of this application provides a photovoltaic module including at least one battery string, wherein the battery string includes at least two of the above-described solar cells. Attached Figure Description

[0100] Figure 1 is a schematic diagram of the structure of the solar cell provided in an embodiment of this application;

[0101] Figure 2 is a partial top view of the solar cell provided in an embodiment of this application;

[0102] Figure 3 is a schematic diagram of another structure of the solar cell provided in the embodiment of this application;

[0103] Figure 4 is a schematic diagram of another structure of the solar cell provided in the embodiment of this application;

[0104] Figure 5 is an image of the marking portion in a solar cell provided in an embodiment of this application;

[0105] Figure 6 is a magnified view of a portion of the structure in Figure 5;

[0106] Figure 7 is a schematic diagram of another structure of the marking part in the solar cell provided in the embodiment of this application;

[0107] Figure 8 is a schematic diagram of another structure of the marking part in the solar cell provided in the embodiment of this application;

[0108] Figure 9 is a schematic diagram of another structure of the marking part in the solar cell provided in the embodiment of this application;

[0109] Figure 10 is a schematic diagram of another structure of the marking part in the solar cell provided in the embodiment of this application;

[0110] Figure 11 is a schematic diagram of another structure of the marking part in the solar cell provided in the embodiment of this application;

[0111] Figure 12 is a schematic diagram of another structure of the solar cell provided in the embodiment of this application;

[0112] Figure 13 is a schematic diagram of another structure of the solar cell provided in the embodiment of this application;

[0113] Figure 14 is a schematic flowchart of the method for manufacturing a solar cell provided in an embodiment of this application;

[0114] Figure 15 is a schematic diagram of the substrate structure in the method for manufacturing a solar cell provided in this application embodiment;

[0115] Figure 16 is a schematic diagram of the formation of a marking structure in the method for manufacturing a solar cell according to an embodiment of this application;

[0116] Figure 17 is a schematic diagram of the structure for forming the marking portion in the method for manufacturing a solar cell provided in this application embodiment;

[0117] Figure 18 is a schematic diagram of the structure for forming the first passivation layer in the method for manufacturing a solar cell according to an embodiment of this application;

[0118] Figure 19 is an image of the marker structure shown in Figure 16;

[0119] Figure 20 is a picture of the marked part shown in Figure 17;

[0120] Figure 21 is a height curve diagram of various parts of the marked section shown in Figure 5;

[0121] Figures 22A-22D are top views of solar cells in various embodiments.

[0122] Reference numerals: 100, Solar cell; 101, Substrate; 10, Substrate; 200, Passivation contact structure; 20, First passivation contact structure; 2011, First contact area; 2012, Second contact area; 201, First tunneling oxide layer; 202, First polycrystalline silicon doped conductive layer; 21, Passivation contact material layer; 211, Tunneling oxide material layer; 212, Polycrystalline silicon doped material layer; 22, Dielectric layer; 30, Second passivation contact structure; 40, Marking structure; 50, Marking portion; 51, First groove; 510, Groove segment; 511, Protrusion structure; 52, Transition treatment area; 53, Third structure; 60, First passivation layer; 70, Second passivation layer; 81, First electrode; 810, First sub-electrode; 811, Second sub-electrode; 82, Second electrode; 90, Doped conductive layer; 91, Textured structure; 92, Third passivation contact structure; Y, First surface; E, Second surface; J, Passivated contact area; F, First region; B, First direction; C, Second direction; G, Receptacle area. Detailed Implementation

[0123] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0124] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used 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. Therefore, they should not be construed as limitations on this invention.

[0125] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0126] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0127] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0128] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0129] The following describes the solar cells of embodiments of this application with reference to the accompanying drawings. It should be noted that the embodiments of this application are applicable to solar cells that use passivated contact structures. In this application, a tunneling oxide passivated contact (TOPCon) cell is used as an example for illustration. The solar cell can also be other types of cells that use passivated contact structures, such as TOPCon-IBC (TBC) cells, etc. Other types of solar cells can have similar corresponding structures, which will not be described in detail here.

[0130] Figure 1 is a schematic diagram of the structure of a solar cell provided in an embodiment of this application; Figure 2 is a partial top view of a solar cell provided in an embodiment of this application; Figure 3 is a schematic diagram of another structure of a solar cell provided in an embodiment of this application; Figure 4 is a schematic diagram of yet another structure of a solar cell provided in an embodiment of this application; Figure 5 is an image of a marking portion in a solar cell provided in an embodiment of this application; Figure 6 is a partial enlarged view of the structure in Figure 5; Figure 7 is a schematic diagram of another structure of a marking portion in a solar cell provided in an embodiment of this application; Figure 8 is a schematic diagram of yet another structure of a marking portion in a solar cell provided in an embodiment of this application; Figure 9 is a schematic diagram of yet another structure of a marking portion in a solar cell provided in an embodiment of this application; Figure 10 is a schematic diagram of yet another structure of a marking portion in a solar cell provided in an embodiment of this application; Figure 11 is a schematic diagram of yet another structure of a marking portion in a solar cell provided in an embodiment of this application; Figure 12 is a schematic diagram of yet another structure of a solar cell provided in an embodiment of this application; Figure 13 is a schematic diagram of yet another structure of a solar cell provided in an embodiment of this application.

[0131] Referring to Figures 1 and 2, the solar cell 100 provided in this embodiment includes a substrate 10, a passivated contact structure 200, and a first electrode 81.

[0132] The substrate 10 includes a first surface Y. A passivation contact structure 200 is disposed on a portion of the first surface Y. A first electrode 81 is disposed on the side of the passivation contact structure 200 facing away from the substrate 10 and is electrically connected to the passivation contact structure 200. The portion of the passivation contact structure 200 includes at least one marking portion 50, which can be configured to serve as a positioning reference during the formation of the first electrode 81. The marking portion 50 can extend inward or outward from the surface, for example, extending into the passivation contact structure 200, or protruding outward from the passivation contact structure 200, or both extending into and protruding outward from the surface. The marking portion 50 extending inward can be a groove. The marking portion 50 extending outward can be a protrusion.

[0133] By providing a passivation contact structure 200 on a portion of the first surface Y, the passivation contact structure 200 only covers a portion of the first surface Y, forming a partial passivation contact structure. Since a marking portion 50 is provided in the partial passivation contact structure 200, the marking portion 50 is configured to serve as a positioning reference during the formation of the first electrode 81. In other words, the marking portion 50 is provided on and / or in the passivation contact structure 200, and the periphery of the marking portion 50 is pre-filled with passivation contact material. Compared to placing the marking portion 50 outside the passivation contact structure 200, the difference in reflectivity between the marking portion 50 and the surrounding background structure is greater, making it easier and more accurate for image-grabbing mechanisms, such as cameras, to grasp the position of the marking portion 50. This results in a more precise position of the first electrode 81 and improves the yield of the solar cell 100.

[0134] In some embodiments, the marking portion 50 does not overlap with the orthographic projection of the first electrode 81 on the first surface Y. Since the marking portion 50 and the orthographic projection of the first electrode 81 on the first surface Y do not overlap, the placement of the marking portion 50 will not affect the first electrode 81.

[0135] In a specific implementation, the first surface Y may include one or more first regions F and one or more passivated contact regions J. The first regions F are defined between adjacent passivated contact regions J. The passivated contact regions J are areas on the first surface Y covered by the passivated contact structure 200, and the first regions F are areas on the first surface Y not covered by the passivated contact structure 200. All areas on the first surface Y other than the first regions F are passivated contact regions J. Since the marking portion 50 is disposed on and / or in the passivated contact structure 200, the marking portion 50 is also disposed in the passivated contact regions J. Referring to FIG22A, in some embodiments, the first surface Y includes a plurality of first regions F and a plurality of passivated contact regions J, with the plurality of passivated contact regions J spaced apart from each other, and adjacent passivated contact regions J may be separated from each other by means of the first regions F.

[0136] In other embodiments, referring to FIG22B, the first surface Y may include a plurality of first regions F and at least one passivation contact region J; each of the first regions F is configured to be defined by the passivation contact region J. In this embodiment, the passivation contact region J may be formed as a large whole, with the plurality of first regions F distributed within the passivation contact region J, such that the entire first surface Y forms a large grid structure. Alternatively, referring to FIG22C, a portion of the first surface Y may be formed as a grid structure, forming at least one first region F, while another portion of the first surface Y may have a plurality of passivation contact regions J, which are spaced apart, and adjacent passivation contact regions J may be separated from each other by means of the first regions F.

[0137] Of course, in the following description of the embodiments of this application, the first surface Y includes a plurality of first regions F and a plurality of passivation contact regions J. The first region F is defined between adjacent passivation contact regions J. The scheme of "the first surface Y includes a plurality of first regions F and at least one passivation contact region J; each of the first regions F is constructed to be defined by the passivation contact region J" is similar and will not be described again here.

[0138] The passivated contact structure 200 may include one or more first passivated contact structures 20 and one or more second passivated contact structures 30. The first passivated contact structure 20 refers to the portion of the passivated contact structure 200 used to provide the first electrode 81, and the second passivated contact structure 30 refers to the portion of the passivated contact structure 200 used to connect with the marking portion 50. The first electrode 81 corresponds to at least a portion of the first passivated contact structure 20, and the marking portion 50 corresponds to at least a portion of the second passivated contact structure 30. In some embodiments, each second passivated contact structure 30 is in contact with or spaced apart from two adjacent first passivated contact structures 20. In FIG1, for the embodiment where the second passivated contact structure 30 is in contact with two adjacent first passivated contact structures 20, the first passivated contact structure 20 and the second passivated contact structure 30 are demarcated by dashed lines for ease of observation. The first passivated contact structure 20 and the second passivated contact structure 30 are respectively located in the corresponding passivated contact area J, and the orthographic projections of the second passivated contact structure 30 and the first passivated contact structure 20 on the first surface Y do not overlap. The first electrode 81 is disposed on the side of the first passivation contact structure 20 away from the substrate 10 and is electrically connected to the first passivation contact structure 20. The marking portion 50 is disposed in the second passivation contact structure 30 and exposed on the side away from the substrate 10.

[0139] In this embodiment, the substrate 10 may further include a second surface E disposed opposite to the first surface Y.

[0140] By making the first surface Y of the substrate 10 include a passivation contact area J and a first area F, a first passivation contact structure 20 is disposed in the corresponding passivation contact area J, a second passivation contact structure 30 is disposed in the corresponding passivation contact area J, and a marking part 50 is disposed in the second passivation contact structure 30. Since the second passivation contact structure 30 is disposed in the passivation contact area J, the marking part 50 is located at a position corresponding to the passivation contact area J. Furthermore, the periphery of the marking part 50 is reserved with passivation contact material in the second passivation contact structure 30. The difference in reflectivity between the marking part 50 and the surrounding background structure is large, making it easier and more accurate for image capturing mechanisms, such as cameras, to capture the position of the marking part 50.

[0141] In a specific implementation, the multiple sub-electrodes in the first electrode 81 can be disposed one-to-one on the side of the first passivation contact structure 20 facing away from the substrate 10. Furthermore, the non-overlapping orthographic projections of the second passivation contact structure 30 and the first passivation contact structure 20 on the first surface Y mean that the first passivation contact structure 20 and the second passivation contact structure 30 are located in different regions of the passivation contact region J. Adjacent second passivation contact structures 30 and first passivation contact structures 20 can be connected as a single unit or arranged at intervals.

[0142] The first passivation contact structure 20 is disposed in the corresponding passivation contact region J. For example, multiple first passivation contact structures 20 may be disposed in each passivation contact region J in a one-to-one correspondence. Alternatively, one passivation contact region J may have one or more first passivation contact structures 20. In this embodiment, the example of multiple first passivation contact structures 20 being disposed in each passivation contact region J in a one-to-one correspondence is used for illustration. Other configurations are similar and will not be described in detail here.

[0143] The second passivation contact structure 30 is provided in the corresponding passivation contact area J. In all passivation contact areas J, all or only some passivation contact areas J are provided with the second passivation contact structure 30. In the passivation contact area J provided with the second passivation contact structure 30, the second passivation contact structure 30 and the passivation contact area J can be in a one-to-one correspondence, or each passivation contact area J can be provided with two or more second passivation contact structures 30.

[0144] In a specific implementation, the first surface Y can be the light-receiving surface of the solar cell 100, and the second surface E can be the backlighting surface of the solar cell 100, or the first surface Y can be the backlighting surface of the solar cell 100, and the second surface E can be the light-receiving surface of the solar cell 100. In the example of Figure 1, the first surface Y is the backlighting surface of the solar cell 100.

[0145] In this embodiment of the application, referring to Figures 1, 2 and 22A, each passivated contact area J can be arranged at intervals along a preset direction, such as the first direction B.

[0146] Furthermore, the first passivation contact structure 20 and the second passivation contact structure 30 have the same film structure. At least one of the first passivation contact structure 20 and the second passivation contact structure 30 includes a first tunneling oxide layer 201 and a first polysilicon doped conductive layer 202 stacked on each other. The first tunneling oxide layer 201 is disposed on the first surface Y, and may be disposed between the first surface Y and the first polysilicon doped conductive layer 202. Of course, the first polysilicon doped conductive layer 202 in the first passivation contact structure 20 and the second passivation contact structure 30 has the same doping type, and may be N-type like the substrate 10, or P-type like the substrate 10. In the example of FIG1, the substrate 10 and the first polysilicon doped conductive layer 202 are both N-type.

[0147] The marking portion 50 can be configured as a positioning reference during the formation process of the first electrode 81. This means that during the formation of the first electrode 81, an image grasping mechanism, such as a camera, is used to grasp the marking portion 50, identify its position information, and then adjust the metallization equipment to achieve the positioning of the first electrode 81 and the first passivation contact structure 20. In this embodiment, it is precisely because of the improved accuracy of grasping the marking portion 50 that the metal paste can be accurately printed onto a predetermined area on the first passivation contact structure 20, thereby forming the first electrode 81 on the first passivation contact structure 20.

[0148] In this embodiment, referring to FIG1, a first passivation layer 60 is formed on the side of the first passivation contact structure 20 and the second passivation contact structure 30 facing away from the substrate 10. The first passivation layer 60 serves to passivate and reduce reflection. The first passivation layer 60 can be a single layer or a multilayer structure, and its material can be aluminum oxide, silicon oxide, silicon nitride, or silicon oxynitride, etc. The first passivation layer 60 covers the first passivation contact structure 20, the second passivation contact structure 30, and each first region F. In some embodiments, the first passivation layer 60 can cover the entire first surface Y.

[0149] Furthermore, the solar cell 100 also includes: a doped conductive layer 90 and a second passivation layer 70 sequentially stacked on the second surface E of the substrate 10, and a second electrode 82. The doped conductive layer 90 is used to form a PN junction with the substrate 10. In this embodiment, the substrate 10 is an N-type substrate, which can be described as a P-type doped conductive layer, such as a boron-doped conductive layer 90 (also known as a P+ type emitter).

[0150] The second passivation layer 70 may include, for example, a passivation layer and an antireflection layer (not shown) sequentially stacked on the doped conductive layer 90. Additionally, a second electrode 82 is disposed on the second passivation layer 70 and electrically connected to the doped conductive layer 90.

[0151] In this embodiment, referring to FIG2, the contour edges of the plurality of first passivated contact structures 20 respectively define a plurality of accommodating regions G. Each second passivated contact structure 30 is located within the corresponding accommodating region G. With this configuration, the second passivated contact structure 30 is essentially embedded within the setting range of the first passivated contact structure 20, without additionally occupying the effective area on the first surface Y, which is beneficial for reducing the overall area of ​​the passivated contact structure 200 of the solar cell 100. Here, the accommodating region G is essentially a hollowed-out area on the first passivated contact structure 20, with the first surface Y exposed from the accommodating region G.

[0152] In this embodiment of the application, only one first passivation contact structure 20 is shown in FIG2. When there are multiple first passivation contact structures 20, for example as shown in FIG22A, the multiple first passivation contact structures 20 are arranged at intervals.

[0153] Each first passivated contact structure 20 includes at least one first contact area 2011 and a plurality of second contact areas 2012 extending from the first contact area 2011 in a direction away from the first contact area 2011. An accommodating area G is formed between two adjacent second contact areas 2012. Of course, the two adjacent second contact areas 2012 need to be connected to the same first contact area 2011. In this case, the accommodating area G is a semi-open area.

[0154] It is understood that, in some other embodiments, the two second contact areas 2012 forming the accommodating area G may also be connected to different first contact areas 2011. Alternatively, the accommodating area G may also be defined by two adjacent first contact areas 2011.

[0155] In some embodiments, the second passivated contact structure 30 may also be disposed between the first passivated contact structure 20 and the edge of the solar cell 100, for example, in the region between the first contact area 2011 and the edge of the solar cell 100.

[0156] In some embodiments, a plurality of first contact regions 2011 of a plurality of first passivated contact structures 20 are arranged at intervals along a first direction B, and a plurality of second contact regions 2012 connected to the same first contact region 2011 are arranged at intervals along a second direction C. Here, the first direction B and the second direction C intersect and are both perpendicular to the thickness direction of the solar cell 100. In some embodiments, the first direction B and the second direction C may be perpendicular.

[0157] In some embodiments, the first electrode 81 includes a plurality of first sub-electrodes 810 and a plurality of second sub-electrodes 811. The plurality of first sub-electrodes 810 are arranged at intervals along a first direction. Each first sub-electrode 810 is connected to at least two second sub-electrodes 811 arranged at intervals along a second direction C. The plurality of first sub-electrodes 810 are disposed one-to-one on the side surface of the first contact area 2011 facing away from the substrate 10, and the plurality of second sub-electrodes 811 are disposed one-to-one on the side surface of the second contact area 2012 connected to the first contact area 2011 facing away from the substrate 10.

[0158] In some embodiments, the second passivated contact structure 30 is located between two adjacent second sub-electrodes 811 in the second direction C, and the two adjacent second sub-electrodes 811 are connected to the same first sub-electrode 810.

[0159] In this embodiment, the first sub-electrode 810 can be the main gate, and the second sub-electrode 811 can be the fine gate.

[0160] Further, as shown in FIG22D, in some other embodiments, each first passivation contact structure 20 may include a plurality of spaced-apart third contact regions 2013, with the accommodating region G disposed between two adjacent third contact regions 2013. In this case, the first passivation contact structure 20 only includes the third contact regions 2013. Correspondingly, the first electrode 81 may include a plurality of third sub-electrodes 812, with each third sub-electrode 812 correspondingly disposed in a third contact region 2013. Of course, the third sub-electrodes 812 may be fine grids, in which case the solar cell 100 may be a gridless solar cell 100.

[0161] Additionally, it is understood that the marking portion 50 is at least partially located between two adjacent second sub-electrodes 811 in the second direction C, and the two adjacent second sub-electrodes 811 are connected to the same first sub-electrode 810.

[0162] In Figure 2, the marking part 50 and the two second sub-electrodes 811 adjacent to the marking part 50 can be arranged at intervals to minimize interference between the second sub-electrodes 811 and the marking part 50 during the grasping process.

[0163] In this embodiment of the application, referring to Figures 1 and 2, the marking portion 50 includes a first groove 51.

[0164] In a specific implementation, as shown in Figure 1, the first groove 51 can extend along the thickness direction of the substrate 10, penetrating deep into the interior of the passivation contact region J of the substrate 10. This makes the morphology of the marking portion 50 more obvious and easier for the camera to capture.

[0165] Alternatively, as shown in Figure 3, the first groove 51 can extend into the passivation contact area J, that is, the first groove 51 extends and terminates at the junction of the first surface Y of the second passivation contact structure 30 and the passivation contact area J along the thickness direction of the solar cell 100.

[0166] Alternatively, the first groove 51 may extend into the interior of the second passivated contact structure 30.

[0167] Further referring to Figure 1, when the first groove 51 extends into the substrate 10, the maximum gap D1 between the bottom wall of the first groove 51 and the first surface Y of the passivation contact area J satisfies: D1 > 1 μm. A deeper groove 51 can have a significant difference in reflectivity relative to the surrounding structure, thus making it easier to grasp.

[0168] In practice, D1 can be 5.1μm, 6μm, 8μm, etc. This setting makes it easier to grasp the first groove 51 in the marking part 50.

[0169] Further, referring to FIG4, in some other embodiments, a protruding structure 511 is provided in the central region of the bottom wall of the first groove 51. In other words, the bottom wall of the first groove 51 includes a central region and an over-etched region adjacent to the edge of the central region. The setting height of the over-etched region relative to the second surface E of the substrate 10 is lower than the setting height of the central region relative to the second surface E, thereby forming a protruding structure 511 in the central region of the bottom wall. Of course, the bottom wall of the first groove 51 can be a plane. However, this application is not limited to this. The bottom wall of the first groove 51 can also be curved, such as a concave surface. It can also be an irregular curved shape, which is related to parameters such as laser energy and power.

[0170] Specifically, the marking portion 50 can be formed by laser processing. When the energy at the center of the laser spot is high, a molten modification area appears on the bottom wall of the first groove 51, making it difficult to etch. Therefore, during wet etching, the etching rate in the central region of the bottom wall of the first groove 51 is lower than the etching rate in the rest of the bottom wall, resulting in a protruding structure 511 in the central region of the bottom wall of the first groove 51, which is higher than the rest of the region. Compared with a flat bottom wall, this arrangement also makes the first groove 51 in the marking portion 50 easier to grasp.

[0171] In this embodiment, the width W1 of the first groove 51 satisfies: W1 < 100 μm. It should be noted that, for ease of observation, all dimensions involved in this application are labeled in Figure 4 below. These dimensions in the various structures of the solar cells 100 described in this embodiment are similar to those in Figure 4, and will not be repeated below.

[0172] In some embodiments, W1 satisfies: 5μm≤W1≤50μm. This setting avoids excessive damage and minimizes impact on efficiency.

[0173] In this embodiment of the application, referring to Figures 1, 4, 5 and 6, the marking portion 50 further includes a transition processing region 52 located between the groove edge of the first groove 51 and the edge of the adjacent second passivation contact structure 30. The reflectivity of the side surface of the transition processing region 52 facing away from the substrate 10 is greater than the reflectivity of the side surface of the second passivation contact structure 30 facing away from the substrate 10.

[0174] The transition processing region 52 includes a melt of the first material and the second material; wherein, the first material is the passivation contact material contained in the second passivation contact structure 30, and the second material is the substrate material contained in the substrate 10. In other words, the transition processing region 52 includes a melt of the passivation contact material included in the second passivation contact structure 30 and the material included in the substrate 10. During the laser forming of the marking part 50, when the laser spot grooves at the position corresponding to the first groove 51, the area covered by the spot is the position of the first groove 51 and the transition processing region 52. If the energy at the center of the spot is high, the first groove 51 will be formed at the position corresponding to the higher energy. At the same time, the film layer through which the laser passes, such as part of the passivation contact material in the second passivation contact structure 30 and part of the material included in the substrate 10, will melt and form a melt around the first groove 51, so that the transition processing region 52 is formed around the first groove 51.

[0175] In this embodiment, the surface of the transition processing region 52 facing away from the substrate 10 is constructed with a plurality of protrusions. The height of the tips of the plurality of protrusions relative to the second surface E of the substrate 10 gradually increases from the groove edge side of the first groove 51 to the edge side of the adjacent second passivation contact structure 30.

[0176] Furthermore, the roughness of the surface of the transition treatment region 52 facing away from the substrate 10 is less than the roughness of the surface of the second passivation contact structure 30 facing away from the substrate 10.

[0177] In this embodiment, the transition processing area 52 may be slightly lower than the surrounding second passivation contact structure 30 to increase recognizability.

[0178] In some embodiments, the side surface of the transition processing region 52 facing away from the substrate 10 is lower by D0 than the side surface of the second passivation contact structure 30 facing away from the substrate 10, where D0 satisfies: 50nm < D0 < 1μm. This makes it easier for the marking portion 50 to have a more obvious optical difference from the surrounding area, facilitating camera capture. Of course, when comparing the height difference between the side surface of the transition processing region 52 facing away from the substrate 10 and the side surface of the second passivation contact structure 30 facing away from the substrate 10, the reference for comparison can be the second surface E.

[0179] In this embodiment of the application, the dimension W2 of the marking portion 50 along the width direction of the first groove 51 satisfies: W2 < 120 μm.

[0180] In practice, the size W2 is less than 90μm, for example, it can be 30μm, 40μm, 50μm, 60μm, 70μm, or 80μm.

[0181] In some embodiments, the surface of the second passivation contact structure 30 facing away from the substrate 10 is further provided with a third structure 53, the third structure 53 is arranged around the marking portion 50, and the reflectivity of the surface of the third structure 53 facing away from the substrate 10 is greater than the reflectivity of the surface of the second passivation contact structure 30 facing away from the substrate 10.

[0182] The third structure 53 refers to the structure formed by the sputtering of molten material from each film layer around the marking portion 50 during the laser film-forming process. Specifically, during the laser formation of the marking portion 50, when the laser spot grooves at the position corresponding to the first groove 51, some of the passivation contact material in the second passivation contact structure 30 and some of the material included in the substrate 10 melt and are sputtered onto the surface of the second passivation contact structure 30 around the transition processing area 52, thereby forming the third structure 53 around the transition processing area 52.

[0183] In this embodiment, the reflectivity of the surface of the third structure 53 facing away from the substrate 10, the reflectivity of the surface of the transition processing region 52 facing away from the substrate 10, and the reflectivity of the bottom wall of the first groove 51 increase sequentially. The surface roughness of the surface of the third structure 53 facing away from the substrate 10, the surface of the transition processing region 52 facing away from the substrate 10, and the bottom wall of the first groove 51 decreases sequentially, while the smoothness increases sequentially, resulting in a sequential increase in reflectivity. This arrangement allows the optical difference between the marking portion 50, the transition processing region 52, and the third structure 53 and the surrounding materials in the second passivation contact structure 30 to gradually increase. Compared to setting the reflectivity of these three components to be the same, the optical difference between the transition processing region 52 and the third structure 53 and the surrounding materials becomes greater, making the marking portion 50 easier for the camera to capture. As shown in the images in Figures 5 and 6, the morphology of the formed third structure 53 is significantly different from that of the surrounding second passivation contact structure 30. The morphology of the third structure 53, the transition treatment area 52, and the first groove 51 are also significantly different, which makes it easier for the camera to capture.

[0184] In some embodiments, referring again to Figures 1 and 4, the first region F is closer to the second surface E of the substrate 10 than the passivation contact region J, that is, the location of the first region F is lower than the location of the passivation contact region J. During the formation of the first passivation contact structure 20 and the second passivation contact structure 30, a full layer of polycrystalline silicon doped material is first formed. Due to the diffusion of dopant elements, an inner diffusion layer is formed within the first surface Y of the substrate 10, resulting in high recombination rates. By configuring it as described above, at least part of the inner diffusion layer of the first region F can be removed, which helps to reduce recombination and improve the efficiency of the solar cell 100.

[0185] In this embodiment, the gap D2 between the first surface Y of the first region F and the first surface Y of the passivation contact region J satisfies: D2 > 1 μm. This setting effectively removes the inner diffusion layer and reduces recombination.

[0186] In this embodiment of the application, the discontinuity D1 between the bottom wall of the first groove 51 and the first surface Y of the passivation contact area J satisfies: D2≤D1.

[0187] In a specific implementation, D2 can be, for example, 5 μm. Alternatively, in some embodiments, D2 may be greater than D1.

[0188] In this embodiment of the application, referring to Figures 7 and 8, the top view outer contour shape of the first groove 51 is circular or annular. Alternatively, the first groove 51 includes at least two intersecting groove segments 510, and the top view outer contour of each groove segment 510 can be elongated. In the example of Figure 2, the number of groove segments 510 is two. Of course, the number of groove segments 510 is not limited to this and can be set to other values ​​as needed.

[0189] It should be noted that, in the embodiments of this application, the outer contour of a component refers to the outer edge of the component as seen when the solar cell 100 is viewed from above. For example, the outer contour of the first groove 51 refers to the outer edge of the first groove 51 as seen when the solar cell 100 is viewed from above, and the outer contour of the groove segment 510 refers to the outer edge of the groove segment 510 as seen when the solar cell 100 is viewed from above.

[0190] In this embodiment of the application, as shown in Figures 2, 7, 8, and 9, the first passivation contact structure 20 and the second passivation contact structure 30 can be connected to each other, for example, by contacting each other. Alternatively, as shown in Figures 10 and 11, the first passivation contact structure 20 and the second passivation contact structure 30 can be spaced apart from each other.

[0191] In some embodiments, the number of marking portions 50 can be multiple, and the multiple marking portions 50 are used to locate the geometric center of the solar cell. For example, when the number of marking portions 50 is four, the four marking portions 50 can be provided at the four corners of the square solar cell 100. Of course, this application is not limited to this, and the number of marking portions 50 can be set to other numbers as needed. The number of marking portions 50 provided on each second passivated contact structure 30 can be one, or it can be set to other numbers as needed.

[0192] In this embodiment, regardless of the number of marking portions 50 provided on each second passivation contact structure, the number of second passivation contact structures 30 can be set to an even number. The even number of second passivation contact structures 30 are grouped into multiple groups of two, with the two second passivation contact structures 30 in each group facing each other with the geometric center of the solar cell 100 as a reference. When the number of second passivation contact structures 30 is four, the four second passivation contact structures 30 can be provided at the four corners of the square solar cell 100. Of course, this application is not limited to this; the number of second passivation contact structures 30 can be set to other numbers as needed.

[0193] In some embodiments, in the schemes shown in FIG2, 7, 8 and 11, the marking portion 50 is spaced apart from the two second sub-electrodes 811 to avoid any potential impact from the second sub-electrodes 811 on the gripping of the marking portion 50.

[0194] In some embodiments, the marking portion 50 and at least one second sub-electrode 811 adjacent to the marking portion 50 are in orthogonal contact or partially overlap on the first surface Y. Alternatively, as shown in Figures 9 and 10, the first groove 51 included in the marking portion 50 may extend beyond the range of the second passivation contact structure 30 and contact the second sub-electrode 811.

[0195] In addition, the edges of the marking portion 50 and the corresponding second passivation contact structure 30 can be spaced apart or connected, as long as the gripping center of the marking portion 50 is within the range of the second passivation contact structure 30.

[0196] In this embodiment of the application, referring to FIG12, the transition processing region 52 is further improved based on the aforementioned embodiment. For example, the transition processing region 52 can also be flush with the surrounding second passivation contact structure 30, that is, the surface of the transition processing region 52 away from the substrate 10 is flush with the surface of the second passivation contact structure 30 away from the substrate 10.

[0197] Referring to Figure 13, based on the above embodiments, this application also provides a solar cell 100 with another structure, which is a bifacial TOPCon cell structure. In the solar cell 100 shown in Figure 13, the structure, shape, and arrangement position of each part, such as the marking part 50, the first passivation contact structure 20, the second passivation contact structure 30, and the first electrode 81, are the same as in the aforementioned embodiments, and will not be described again here.

[0198] In Figure 13, the first surface Y of the solar cell 100 is the light-receiving surface, and the second surface E is the backlight surface. A textured structure 91 is provided at various positions on the first surface Y. Therefore, the bottom wall and side wall of the first groove 51 are both formed with textured structures 91.

[0199] A third passivation contact structure 92 (replacing the doped conductive layer 90) and a second passivation layer 70 are sequentially stacked on the second surface E.

[0200] The third passivation contact structure 92 completely covers the second surface E. The third passivation contact structure 92 includes a third tunneling oxide layer and a third polysilicon-doped conductive layer stacked on top of each other. The third tunneling oxide layer is disposed on the second surface E, located between the second surface E and the third polysilicon-doped conductive layer. Of course, the doping type of the third polysilicon-doped conductive layer in the third passivation contact structure 92 is opposite to that of the first polysilicon-doped conductive layer 202 in the first passivation contact structure 20 and the second passivation contact structure 30.

[0201] In addition, in this embodiment of the application, the solar cell 100 may include multiple sides, at least some of which are cut surfaces, so that the solar cell 100 is a structure that has been cut.

[0202] The second aspect of this application provides a method for manufacturing a solar cell, used to manufacture the solar cell 100 of the above embodiments. That is, the solar cell 100 of all the above embodiments can be manufactured by the following method for manufacturing solar cells.

[0203] Figure 14 is a flowchart illustrating the method for fabricating a solar cell according to an embodiment of this application; Figure 15 is a structural diagram of the substrate in the method for fabricating a solar cell according to an embodiment of this application; Figure 16 is a schematic diagram illustrating the formation of a marking structure in the method for fabricating a solar cell according to an embodiment of this application; Figure 17 is a structural diagram illustrating the formation of a marking portion in the method for fabricating a solar cell according to an embodiment of this application; Figure 18 is a structural diagram illustrating the formation of a first passivation layer in the method for fabricating a solar cell according to an embodiment of this application; Figure 19 is an image of the marking structure shown in Figure 16; Figure 20 is an image of the marking portion shown in Figure 17; Figure 21 is a height curve of the marking portion shown in Figure 5. The images illustrated in Figures 5, 6, 19, 20, and 21 were all obtained using an optical microscope.

[0204] Referring to Figures 14-21, the method for manufacturing a solar cell provided in this embodiment includes:

[0205] S10. A substrate is provided, the substrate including a substrate, a passivation contact material layer and a dielectric layer sequentially stacked on a first surface of the substrate, the first surface of the substrate including a first region and a passivation contact region.

[0206] S20. The portion of the dielectric layer covering the first region is patterned, and a marking structure is formed at the location where the dielectric layer covers the passivation contact area, the marking structure extending at least to the passivation contact material layer.

[0207] S30. Using the portion of the dielectric layer that has been patterned and formed with a marking structure that covers the passivation contact area as a mask, the portion of the passivation contact material layer located in the first region is removed, and the dielectric layer is removed to form a marking part of the marking structure.

[0208] S40. A first passivation layer is formed on the side of the passivation contact material layer away from the substrate. Using the mark as a positioning reference, a first electrode is formed at the position where the first passivation layer covers the passivation contact area.

[0209] In the above scheme, by patterning the portion of the dielectric layer 22 covering the first region F, a marking structure 40 is formed at the position where the dielectric layer 22 covers the passivation contact region J. Using the portion of the dielectric layer 22 with the patterned marking structure 40 covering the passivation contact region J as a mask, the portion of the passivation contact material layer 21 located in the first region F is removed. Therefore, the portion of the passivation contact material layer 21 covering the passivation contact area J will be retained. The dielectric layer 22 will be removed later to form the marking structure 40 into the marking portion 50. Thus, the marking portion 50 is ultimately formed on the portion of the passivation contact material layer 21 covering the passivation contact area J. This leaves passivation contact material around the marking portion 50. Compared to the marking portion 50 being located in the first area F (without passivation contact material), this results in a significant difference in reflectivity between the marking portion 50 and the surrounding background structure. Subsequently, using the marking portion 50 as a positioning reference, during the formation of the first electrode 81 at the location where the first passivation layer 60 covers the passivation contact area J, it makes it easier and more accurate for image-grabbing mechanisms, such as cameras, to capture the position of the marking portion 50. The more precise positioning of the first electrode 81 also improves the yield of the solar cell 100.

[0210] It should be noted that in step S20, the step of patterning the portion of the dielectric layer 22 covering the first region F and forming the mark structure 40 at the location where the dielectric layer 22 covers the passivation contact region J can be performed first, followed by the step of forming the mark structure 40 at the location where the dielectric layer 22 covers the passivation contact region J. Alternatively, the step of forming the mark structure 40 at the location where the dielectric layer 22 covers the passivation contact region J can be performed first, followed by the step of patterning the portion of the dielectric layer 22 covering the first region F. Alternatively, the steps of patterning the portion of the dielectric layer 22 covering the first region F and forming the mark structure 40 at the location where the dielectric layer 22 covers the passivation contact region J can be performed simultaneously.

[0211] In this embodiment of the application, step S20, which involves forming a marking structure 40 at the location where the dielectric layer 22 covers the passivation contact region J, specifically includes:

[0212] The first laser is used to locally scan the position of the dielectric layer 22 covering the passivated contact area J to form a marking structure 40.

[0213] In some embodiments, step S20, which involves patterning the portion of the dielectric layer 22 covering the first region F, specifically includes:

[0214] The second laser is used to scan the entire area of ​​the first region F covered by the dielectric layer 22.

[0215] The second laser has a larger spot size than the first laser, and the second laser has a higher laser power than the first laser.

[0216] During the laser treatment of the portion of the dielectric layer 22 covering the first region F and the passivation contact region J, a larger laser spot with higher power is required because the laser treatment area of ​​the dielectric layer 22 covering the first region F is relatively large. If the same laser is used to treat the portion of the dielectric layer 22 covering the passivation contact region J to create the marking structure 40, the resulting marking structure 40 will be too large due to the large laser spot size, which affects the passivation effect of the solar cell 100 surface and also prolongs the processing time. In addition, during the large-area film unfolding process, the laser spot needs to be shaped to ensure that the energy of the laser spot irradiating the portion of the dielectric layer 22 covering the first region F is uniform. Therefore, the laser required for laser processing of the dielectric layer 22 covering the first region F needs to have the characteristics of large spot size, high energy and good uniformity (requiring shaping). When laser processing of the portion of the dielectric layer 22 covering the passivation contact region J is performed using a laser with these characteristics, the overall process cost is high due to the high cost of the laser, and the passivation performance at the mark structure 40 position will also be affected.

[0217] In the above technical solution, two independent lasers, a second laser and a first laser, are used to laser process the portions of the dielectric layer 22 covering the first region F and the passivation contact region J, respectively. The spot size of the second laser is larger than that of the first laser, and the laser power of the second laser is also greater than that of the first laser. The spot size and laser power of the first laser are both smaller, which not only reduces costs but also results in a smaller area of ​​the final marked portion 50, improving the passivation performance of the solar cell 100. Specifically, for example, the first laser can be an infrared laser, and the second laser can be a green picosecond laser. Using an infrared laser as the first laser to laser process the portion of the dielectric layer 22 covering the passivation contact region J to form the marked structure 40 avoids the problem of repeated processing due to the small amount of damage to the film layer caused by green picosecond lasers, thus further improving production capacity. Simultaneously, using a green picosecond laser as the second laser to laser process the portion of the dielectric layer 22 covering the first region F allows for efficient step-by-step processing of the two locations, which also helps improve the passivation performance of the solar cell 100.

[0218] In this embodiment, the first laser has a spot diameter of less than 120 μm and a power of 10 W-100 W, optionally 10 W-15 W. It is understood that the energy can be increased by increasing the overlap rate. The second laser has a spot diameter of greater than 150 μm and a power of 40 W-200 W, preferably 60 W-80 W. Specifically, the first laser can be a Gaussian beam. It can also be a shaped spot, such as a square spot. Since the first laser is used to form the marking structure 40, the requirements for the spot, especially for uniformity, are slightly lower than for the second laser. An unshaped Gaussian beam can be selected to reduce costs.

[0219] In this embodiment of the application, the step of using a first laser to perform a local scan of the position where the dielectric layer 22 covers the passivation contact region J specifically includes:

[0220] The first laser is used to scan the dielectric layer 22 back and forth along the first path and the second path to form a marking structure 40 with an intersecting outer contour on the dielectric layer 22, wherein the first path and the second path intersect and are both straight paths.

[0221] Alternatively, in another embodiment, a first laser is used to scan the dielectric layer 22 along a ring-shaped path to form a marking structure 40 with a ring-shaped outer contour.

[0222] Alternatively, in other embodiments, a first laser is used to scan the dielectric layer 22 along a circular region to form a marker structure 40 with a circular outer contour.

[0223] In this embodiment of the application, referring to Figures 1, 16 and 17, the marking portion 50 includes a first groove 51.

[0224] In step S30, the portion of the dielectric layer 22, which has been patterned and has the marking structure 40 formed therein, covering the passivation contact region J, is used as a mask to remove the portion of the passivation contact material layer 21 located in the first region F; and the dielectric layer 22 is removed to form the marking portion 50 of the marking structure 40.

[0225] The portion of the passivation contact material layer 21 located in the first region F is removed by wet etching, and the patterned dielectric layer 22 is also removed to form a first groove 51 in the passivation contact material layer 21 covering the passivation contact region J. After removing the portion of the passivation contact material layer 21 located in the first region F, the remaining passivation contact material layer 21 forms a first passivation contact structure 20 covering the passivation contact region J, and a second passivation contact structure 30 covering the passivation contact region J.

[0226] Furthermore, the marking structure 40 also includes a transition processing area 52 located at the edge of the groove of the first groove 51; the energy intensity at the central local area of ​​the first laser spot is greater than the energy intensity at the edge area of ​​the spot;

[0227] After wet etching, in the passivation contact material layer 21, a portion of the area treated by the central local region forms a first groove 51, and another portion of the area treated by the edge region forms a transition treatment region 52. The transition treatment region 52 includes the dielectric layer 22, the passivation contact material layer 21, and the molten material contained in the substrate 10. Alternatively, after wet etching, the area of ​​the passivation contact material layer 21 treated by the central local region forms the first groove 51, and the area treated by the edge region forms the transition treatment region 52.

[0228] Of course, as an optional embodiment, the first laser can be a Gaussian beam. This ensures that the energy intensity at the center of the first laser spot is greater than the energy intensity at the edge of the spot. Alternatively, it can be other types of beams, as long as the energy intensity at the center of the first laser spot is greater than the energy intensity at the edge of the spot.

[0229] In this embodiment, after the above-mentioned wet etching, a third structure 53 is formed around the marking structure 40. The reflectivity of the surface of the third structure 53 facing away from the substrate 10 is greater than the reflectivity of the surface of the passivation contact material layer 21 facing away from the substrate 10.

[0230] It is understandable that when the first laser is used to form the marking structure 40, as shown in Figure 16, the marking structure 40 may include a first groove 51, a transition processing area 52 and a third structure 53. Subsequently, during wet etching, impurities on each part are removed, thereby forming a clearer marking part 50.

[0231] Alternatively, the first laser may only melt the film layers in the area where the first groove 51 will be formed, forming the transition processing area 52 and the third structure 53. In the subsequent wet etching process, the melted part is removed to form the first groove 51 and finally the marking part 50.

[0232] As shown in Figure 17, as mentioned above, the third structure 53 refers to the structure formed by the sputtering of the molten material of each film layer around the marking structure 40 during the laser film-opening process. After wet etching, its surface reflectivity is greater than that of the first passivation contact structure 20 and the second passivation contact structure 30, which facilitates camera capture.

[0233] In this embodiment of the application, the step of removing the portion of the passivation contact material layer 21 located in the first region F by using the portion of the dielectric layer 22, which has been patterned and has a marker structure 40 formed thereon, covering the passivation contact region J, as a mask includes:

[0234] The first region F of the substrate 10 is etched inward in the thickness direction of the substrate 10 to form a height difference D2. As described earlier in the description of the solar cell 100, this arrangement can remove the inner diffusion layer in the substrate 10 to some extent.

[0235] Further, in step S20, the step of patterning the portion of the dielectric layer 22 covering the first region F includes:

[0236] The portion of the dielectric layer 22 covering the first region F is modified;

[0237] The step of removing the portion of the passivation contact material layer 21 located in the first region F by using the portion of the patterned dielectric layer 22 with the marked structure 40 covering the passivation contact region J as a mask specifically includes:

[0238] By wet etching, the portion of the dielectric layer 22 covering the first region F is removed, and the portion of the passivation contact material layer 21 located in the first region F is also removed.

[0239] Alternatively, as shown in Figures 16 and 17, the step of patterning the portion of the dielectric layer 22 covering the first region includes:

[0240] Remove the portion of the dielectric layer 22 that covers the first region F;

[0241] The step of removing the portion of the passivation contact material layer 21 located in the first region F by using the portion of the patterned dielectric layer 22 with the marked structure 40 covering the passivation contact region J as a mask specifically includes:

[0242] The portion of the passivation contact material layer 21 located in the first region F is removed by wet etching.

[0243] In this embodiment of the application, the method for manufacturing a solar cell further includes the step of cutting the solar cell 100 along its thickness into multiple solar cell substrates, wherein the number of marking portions 50 in the partially cut solar cell substrates is 0, and the number of marking portions 50 in the partially cut solar cell substrates is 1 or more.

[0244] The following example illustrates the method for manufacturing a solar cell according to an embodiment of this application:

[0245] Step 1: As shown in Figure 15, a passivation contact material layer 21 and a dielectric layer 22 are sequentially stacked on the first surface Y of the substrate 10. The first surface Y of the substrate 10 includes a passivation contact region J and a first region F. At this time, the dielectric layer 22 can be formed naturally during the formation process of the passivation contact material layer 21. For example, when the passivation contact material layer 21 includes a phosphorus-doped polysilicon doped material layer 212, the dielectric layer 22 can be PSG.

[0246] Step 2, as shown in Figures 16 and 19, uses the second laser to remove the portion of the dielectric layer 22 covering the first region F, and uses the first laser to form a marking structure 40 at the position where the dielectric layer 22 covers the passivation contact region J. The marking structure 40 extends at least to the passivation contact material layer 21.

[0247] Step 3: As shown in Figures 17 and 20, using the patterned dielectric layer 22 as a mask, specifically the portion of the dielectric layer 22 covered by the patterned marking structure 40 covering the passivation contact region J, wet etching is performed to remove the portion of the passivation contact material layer 21 located in the first region F, while retaining the portion located in the passivation contact region J, forming the first passivation contact structure 20 and the second passivation contact structure 30. The patterned dielectric layer 22 is then removed to form a first groove 51 in the passivation contact material layer 21 covering the passivation contact region J, and a transition processing region 52 is formed around the first groove 51. A third structure 53 is formed around the transition processing region 52, thereby forming the marking portion 50. It should be noted that the first groove 51 can be a continuous or discontinuous groove structure in its extension direction.

[0248] Step 4: As shown in Figures 5, 18, and 21, a first passivation layer 60 is formed on the side of the first passivation contact structure 20 and the second passivation contact structure 30 facing away from the substrate 10. Using the marker portion 50 as a positioning reference, a first electrode 81 is formed at the position where the first passivation layer 60 covers the passivation contact area J. The first electrode 81 penetrates the first passivation layer 60 to contact the first passivation contact structure 20.

[0249] Figure 21 is a schematic diagram of the thickness dimension of the marking portion 50 in the direction R perpendicular to its extension direction. A point is selected on the side of the first groove 51 as the origin point O. The horizontal axis L1 represents the distance from the origin point O, and the vertical axis L2 represents the thickness dimension of each position in the thickness direction of the solar cell 100. As can be seen from Figure 21, a protruding structure 511 is formed within the first groove 51. The first groove 51 has a relatively obvious concavity relative to the surrounding transition processing area 52, making it easier for the camera to capture.

[0250] It is understood that the formation steps of the solar cell 100 shown in FIG1 may include, for example, forming a doped conductive layer 90 on the second surface E of the substrate 10 before step 1, and after step 4, forming a second passivation layer 70 on the surface of the doped conductive layer 90 away from the substrate 10, and forming a second electrode 82 on the second passivation layer 70.

[0251] This application also provides a photovoltaic module and a photovoltaic system. The photovoltaic module includes at least one battery string, and the battery string includes at least two solar cells 100 as described above, which can be connected together by string welding.

[0252] A photovoltaic (PV) system includes the aforementioned PV modules. PV systems can be applied in PV power plants, such as ground-mounted, rooftop, and floating power plants, as well as in equipment or devices that utilize solar energy for power generation, such as user solar power supplies, solar streetlights, solar cars, and solar buildings. Of course, it's understood that the application scenarios for PV systems are not limited to these; that is, PV systems can be applied in all areas that require solar energy for power generation. Taking a PV power grid as an example, a PV system can include PV arrays, combiner boxes, and inverters. A PV array can be an array combination of multiple PV modules; for example, multiple PV modules can form multiple PV arrays. The PV arrays are connected to combiner boxes, which collect the current generated by the PV arrays. The collected current flows through an inverter, converts it into AC power required by the mains grid, and then connects to the mains grid to achieve solar power supply.

[0253] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0254] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A solar cell, characterized by, include: Substrate, the substrate including a first surface; A passivated contact structure is disposed on a portion of the first surface; as well as A first electrode is disposed on the side of the passivation contact structure opposite to the substrate and is electrically connected to the passivation contact structure. Some of the passivated contact structures are provided with marking portions.

2. The solar cell according to claim 1, characterized in that, The first electrode includes a plurality of first sub-electrodes and a plurality of second sub-electrodes, the plurality of first sub-electrodes being arranged at intervals along a first direction, and each first sub-electrode being connected to at least two second sub-electrodes arranged at intervals along a second direction; The marking portion is at least partially located between the two second sub-electrodes, and the two adjacent second sub-electrodes are connected to the same first sub-electrode; the first direction and the second direction intersect and are both perpendicular to the thickness direction of the solar cell.

3. The solar cell according to claim 2, characterized in that, The marking portion and the two second sub-electrodes adjacent to the marking portion are spaced apart; or The orthographic projection of the marking portion and at least one second sub-electrode adjacent to the marking portion on the first surface is in contact or overlap.

4. Solar cell according to any of claims 1 to 3, characterized in that The first surface includes one or more first regions and one or more passivated contact regions; The passivated contact structure includes one or more first passivated contact structures and one or more second passivated contact structures; The first passivation contact structure and the second passivation contact structure are respectively disposed in the corresponding passivation contact area, and the orthographic projection of the second passivation contact structure and the first passivation contact structure on the first surface does not overlap. The first electrode is disposed on the side of the first passivation contact structure opposite to the substrate; the marking portion is disposed on the second passivation contact structure.

5. The solar cell according to claim 4, characterized in that, The contour edges of the multiple first passivated contact structures respectively define multiple accommodating areas; Each of the second passivated contact structures is located within the corresponding accommodating region.

6. The solar cell according to claim 5, characterized in that, The plurality of first passivated contact structures are arranged at intervals from each other; Each of the first passivated contact structures includes a first contact area and a plurality of second contact areas extending from the first contact area in a direction away from the first contact area; The receiving area is formed between two adjacent second contact areas, and the two adjacent second contact areas are connected to the same first contact area.

7. The solar cell according to claim 6, characterized in that The plurality of first contact areas of the plurality of first passivated contact structures are arranged at intervals along a first direction, and the plurality of second contact areas connected to the same first contact area are arranged at intervals along a second direction. The first direction and the second direction intersect and are both perpendicular to the thickness direction of the solar cell.

8. The solar cell of claim 7, wherein, The first electrode includes a plurality of first sub-electrodes and a plurality of second sub-electrodes, and each first sub-electrode is connected to at least two second sub-electrodes arranged at intervals in the second direction; The plurality of first sub-electrodes are respectively disposed on the side surface of the first contact area away from the substrate, and the plurality of second sub-electrodes are respectively disposed on the side surface of the second contact area away from the substrate. The second passivated contact structure is located between two adjacent second sub-electrodes in the second direction, and the two adjacent second sub-electrodes are connected to the same first sub-electrode.

9. Solar cell according to any of claims 5-8, characterized in that, Each of the first passivated contact structures includes a plurality of spaced-apart third contact areas, and the accommodating area is disposed between two adjacent third contact areas; The first electrode includes a plurality of third sub-electrodes, which are disposed one-to-one in the third contact area.

10. Solar cell according to any of claims 4-9, characterized in that, At least one of the first passivation contact structure and the second passivation contact structure includes a first tunneling oxide layer and a first polysilicon doped conductive layer stacked on each other, wherein the first tunneling oxide layer is disposed on the first surface.

11. The solar cell according to any one of claims 4 to 10, characterized in that, The first passivated contact structure and the second passivated contact structure are arranged at intervals.

12. The solar cell according to any one of claims 4 to 11, characterized in that, The marking portion is spaced from the edge corresponding to the second passivated contact structure.

13. The solar cell according to any one of claims 4 to 12, characterized in that, The number of the marking portions is multiple; The plurality of markings are used to locate the geometric center of the solar cell.

14. The solar cell according to any one of claims 4 to 13, characterized in that, The marking portion includes a first groove; The first groove extends into the interior of the second passivated contact structure; or The first groove extends to and ends at the junction of the second passivated contact structure and the first surface of the passivated contact area along the thickness direction of the solar cell; or The first groove extends into the interior of the substrate corresponding to the passivation contact area.

15. The solar cell of claim 14, wherein, When the first groove extends into the substrate corresponding to the passivation contact region, the maximum gap D1 between the bottom wall of the first groove and the first surface of the passivation contact region satisfies: D1 > 1 μm.

16. The solar cell according to claim 14 or 15, characterized in that The bottom wall of the first groove includes a central region and an over-etched area adjacent to the edge of the central region; The height of the over-etched region relative to the second surface of the substrate is lower than the height of the central region relative to the second surface; The second surface is disposed opposite to the first surface.

17. The solar cell according to any of claims 14 to 16, characterized in that The width W1 of the first groove satisfies: W1 < 100 μm.

18. The solar cell according to any of claims 14 to 17, characterized in that The marking portion further includes a transition processing area located between the groove edge of the first groove and the edge of the adjacent second passivated contact structure; The reflectivity of the surface of the transition treatment region facing away from the substrate is greater than the reflectivity of the surface of the second passivated contact structure facing away from the substrate.

19. The solar cell of claim 18, wherein, The surface of the transition processing region facing away from the substrate has multiple protrusions; The height of the tips of the plurality of protrusions relative to the second surface of the substrate gradually increases from one side of the groove edge of the first groove to the edge of the adjacent second passivation contact structure.

20. The solar cell according to claim 18 or 19, characterized in that, The roughness of the surface of the transition treatment region facing away from the substrate is less than the roughness of the surface of the second passivation contact structure facing away from the substrate.

21. The solar cell according to any of claims 18-20, characterized in that, The transition processing zone includes a melt of the first material and the second material; Wherein, the first material is the passivation contact material contained in the second passivation contact structure, and the second material is the substrate material contained in the substrate.

22. The solar cell according to any of claims 18 to 21, characterized in that The surface of the transition treatment region facing away from the substrate is lower by D0 than the surface of the second passivation contact structure facing away from the substrate, wherein D0 satisfies: 50nm < D0 < 1μm.

23. The solar cell according to any of claims 18 to 22, characterized in that The dimension W2 of the marking portion along the width direction of the first groove satisfies: W2 < 120 μm.

24. The solar cell of any of claims 18-23, wherein, The surface of the second passivated contact structure facing away from the substrate is further provided with a third structure; The third structure is arranged around the marking portion, and the reflectivity of the surface of the third structure facing away from the substrate is greater than the reflectivity of the surface of the second passivated contact structure facing away from the substrate.

25. The solar cell of claim 24, wherein, The reflectivity of the surface of the third structure facing away from the substrate, the reflectivity of the surface of the transition processing area facing away from the substrate, and the reflectivity of the bottom wall of the first groove increase sequentially.

26. The solar cell of any of claims 14-25, wherein, The outer contour of the first groove is circular or annular; or, The first groove includes at least two intersecting groove segments.

27. The solar cell of any of claims 4-26, wherein, The first region is closer to the second surface of the substrate than the passivation contact region, and the second surface is disposed opposite to the first surface.

28. The solar cell of claim 28, wherein, The discontinuity D2 between the first surface of the first region and the first surface of the passivated contact region satisfies: D2 > 1 μm.

29. The solar cell of claim 29, wherein, The marking portion includes a first groove, and the discontinuity D1 between the bottom wall of the first groove and the first surface of the passivation contact area satisfies the following condition: D2≤D1.

30. The solar cell of any of claims 1-29, wherein, The first surface includes a plurality of first regions and at least one passivated contact region; At least a portion of each of the first regions is configured to be defined by the passivated contact region surrounding it.

31. The solar cell of any of claims 1-30, wherein, The solar cell includes multiple sides, at least some of which are cut surfaces.

32. The solar cell of any of claims 1-31, wherein, The marking portion does not overlap with the projection of the first electrode onto the first surface.

33. The solar cell of any of claims 1-32, wherein, The marking portion is configured to serve as a positioning reference during the formation of the first electrode.

34. A method of fabricating a solar cell, the method comprising: include: A substrate is provided, the substrate comprising a substrate, a passivation contact material layer and a dielectric layer sequentially stacked on a first surface of the substrate, the first surface of the substrate comprising a first region and a passivation contact region; The portion of the dielectric layer covering the first region is patterned, and a marking structure is formed at the location where the dielectric layer covers the passivation contact region, the marking structure extending at least to the passivation contact material layer; Using the portion of the dielectric layer that has been patterned and formed with a marking structure covering the passivation contact area as a mask, the portion of the passivation contact material layer located in the first area is removed, and the dielectric layer is removed to form a marking portion of the marking structure; A first passivation layer is formed on the side of the passivation contact material layer away from the substrate. Using the marking portion as a positioning reference, a first electrode is formed at the position where the first passivation layer covers the passivation contact area.

35. The method of producing a solar cell according to claim 34, wherein The step of forming a marking structure at the location where the dielectric layer covers the passivation contact area specifically includes: The marking structure is formed by locally scanning the position of the dielectric layer covering the passivated contact area using a first laser.

36. The method of producing a solar cell according to claim 35, wherein The step of patterning the portion of the dielectric layer covering the first region specifically includes: The entire area covered by the dielectric layer in the first region is scanned using a second laser. The second laser has a larger spot size than the first laser, and the second laser has a higher laser power than the first laser.

37. The method of producing a solar cell according to claim 36, wherein The first laser has a spot diameter of less than 120μm and a power of 10W-100W. The second laser has a spot diameter greater than 150μm and a power of 40W-200W.

38. The method of any of claims 35-37, wherein the method further comprises: The step of using a first laser to perform a local scan of the location where the dielectric layer covers the passivated contact area specifically includes: The first laser is used to scan the dielectric layer back and forth along a first path and then back and forth along a second path to form a marking structure with an intersecting outer contour on the dielectric layer, wherein the first path and the second path intersect and are both straight paths; or The first laser is used to scan the dielectric layer along a circular path to form the marking structure with a ring-shaped outer contour; or The first laser is used to scan the dielectric layer along a circular region to form the marking structure with a circular outer contour.

39. The method of any one of claims 35-38, wherein the method further comprises: The marking portion includes a first groove; In the step of using the portion of the dielectric layer that has been patterned and formed with a marking structure, covering the passivation contact area, as a mask, removing the portion of the passivation contact material layer located in the first area, and removing the dielectric layer to form the marking portion of the marking structure: The passivation contact material layer located in the first region is removed by wet etching, and the dielectric layer is also removed, so as to form the first groove in the passivation contact material layer covering the passivation contact region.

40. The method of producing a solar cell according to claim 39, wherein The marking structure further includes a transition processing area located at the edge of the groove of the first groove; the energy intensity at the central local area of ​​the first laser spot is greater than the energy intensity at the edge area of ​​the spot; After the wet etching, in the passivation contact material layer, in the area treated by the central local area, a portion of the location forms the first groove, and another portion of the location and the area treated by the edge area form the transition processing area. The transition processing area includes the dielectric layer, the passivation contact material layer and the molten material included in the substrate.

41. The method of producing a solar cell according to claim 40, wherein After the wet etching, a third structure is formed around the marking structure. The reflectivity of the surface of the third structure facing away from the substrate is greater than the reflectivity of the surface of the passivation contact material layer facing away from the substrate.

42. The method of any one of claims 39-41, wherein the method further comprises: In the step of removing the portion of the passivation contact material layer located in the first region by using the portion of the dielectric layer that has been patterned and formed with a marked structure covering the passivation contact region as a mask, the first region of the substrate is also etched inwards in the thickness direction of the substrate by a portion of the thickness.

43. The method of any of claims 34-42, wherein the method further comprises: The step of patterning the portion of the dielectric layer covering the first region includes: The portion of the dielectric layer covering the first region is modified; The step of using the portion of the dielectric layer that has been patterned and formed with a marked structure, covering the passivation contact region, as a mask to remove the portion of the passivation contact material layer located in the first region specifically includes: By wet etching, the portion of the dielectric layer covering the first region is removed, and the portion of the passivation contact material layer located in the first region is also removed.

44. The method of any of claims 34-43, wherein the method further comprises: The step of patterning the portion of the dielectric layer covering the first region includes: Remove the portion of the dielectric layer that covers the first region; The step of using the portion of the dielectric layer that has been patterned and formed with a marked structure, covering the passivation contact region, as a mask to remove the portion of the passivation contact material layer located in the first region specifically includes: The portion of the passivated contact material layer located in the first region is removed by wet etching.

45. The method of any of claims 34-44, wherein the method further comprises: It also includes the step of cutting the solar cell along its thickness into multiple solar cell substrates, wherein the number of marking portions in the partially cut solar cell substrates is 0, and the number of marking portions in the partially cut solar cell substrates is 1 or more.

46. A solar cell, characterized by, It is manufactured using the method for manufacturing a solar cell as described in any one of claims 34-45.

47. A photovoltaic module, comprising: It includes at least one battery string, said battery string comprising at least two solar cells as described in any one of claims 1-33, 46.

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