Solar cell and manufacturing method therefor

Abstract

The present application relates to a solar cell and a manufacturing method therefor. The solar cell comprises: a substrate; and a doped layer, the doped layer comprising first doping patterns and a second doping pattern which are alternately arranged on the surface of a first side of the substrate along a preset direction, and an insulating isolation trench being constructed between each first doping pattern and the second doping pattern adjacent thereto, wherein a mark point is further provided on the surface of the first side of the substrate, and the mark point is located on the inner side the outer contour line of the first doping pattern, and is used as a positioning reference in the process of forming the second doping pattern.

Description

Solar cell and manufacturing method thereof

[0001] Cross-reference to Related Applications

[0002] This application claims priority to the Chinese patent application No. 202410949149.8, filed on July 16, 2024, and entitled "Solar cell and manufacturing method thereof", the contents of which are hereby incorporated by reference in its entirety. TECHNICAL FIELD

[0003] The present application relates to the field of photovoltaic technology, and in particular, to a solar cell and a manufacturing method thereof. BACKGROUND

[0004] IBC (Interdigitated Back Contact) cells appeared in the 1970s, which respectively perform local phosphorus and boron diffusion on the back of the cell to form P and N regions with interdigitated cross arrangement; the positive and negative electrodes of the IBC cell are both on the back of the cell, and the front surface is free of metal shading, which greatly improves the optical absorption of the cell. The process flow of the IBC cell is more complex than that of the bifacial cell, and the precision requirement for the back process is higher, so a mark point arranged on the back is used as a positioning reference to assist in patterning and positioning the silicon wafer. However, the related art has the problem of low grabbing precision of the mark point, which also reduces the yield of the solar cell. SUMMARY

[0005] A first aspect of the embodiments of the present application provides a solar cell, comprising:

[0006] a substrate; and

[0007] a doped layer, the doped layer comprising a first doped pattern and a second doped pattern alternately arranged on a surface of a first side of the substrate along a preset direction, and an insulating isolation groove is configured between each adjacent first doped pattern and second doped pattern;

[0008] wherein the surface of the first side of the substrate is further provided with a mark point, the mark point is located inside an outer contour line of the first doped pattern, and is used as a positioning reference in the process of forming the second doped pattern.

[0009] In some embodiments, the solar cell further comprises:

[0010] a first passivation layer, the first passivation layer being arranged on a surface of the doped layer away from the substrate;

[0011] a first electrode and a second electrode, the first electrode being arranged on the first passivation layer at a position corresponding to the first doped pattern and being in ohmic contact with the first doped pattern, and the second electrode being arranged on the first passivation layer at a position corresponding to the second doped pattern and being in ohmic contact with the second doped pattern;

[0012] The mark point is arranged apart from both the first electrode and the second electrode.

[0013] In some embodiments, the first electrode comprises a plurality of first main grids and a plurality of first sub-grids, each first main grid being connected with a plurality of first sub-grids; the second electrode comprises a plurality of second main grids and a plurality of second sub-grids, each second main grid being connected with a plurality of second sub-grids; the plurality of first sub-grids and the plurality of second sub-grids are arranged alternately.

[0014] The mark point is located on a side of the second sub-grid facing the first main grid in the extending direction of the second sub-grid; or the mark point is located on a side of the first sub-grid facing the second main grid in the extending direction of the first sub-grid.

[0015] In some embodiments, the mark point is arranged apart from both the first electrode and the second electrode.

[0016] In some embodiments, the mark point is arranged apart from both the first electrode and the second electrode.

[0017] In some embodiments, the mark point is a groove structure formed on the first doped pattern.

[0018] In some embodiments, the mark point can be distinguished from the first doped pattern and the second doped pattern on an optical image.

[0019] A solar cell, comprising:

[0020] a substrate; and

[0021] a doped layer, the doped layer comprising a first doped pattern and a second doped pattern arranged alternately on a surface of a first side of the substrate along a preset direction, an insulating isolation groove being configured between each adjacent first doped pattern and second doped pattern.

[0022] The surface of the first side of the substrate is further provided with a mark point, the mark point being located inside an outer contour line of the first doped pattern.

[0023] In some embodiments, the mark point can be distinguished from the first doped pattern and the second doped pattern on an optical image.

[0024] A second aspect of the embodiments of the present application provides a manufacturing method of a solar cell, comprising:

[0025] providing a substrate, the substrate comprising a substrate and a first doped material layer provided on a surface of a first side of the substrate, the surface of the first side having a first doped region and a second doped region arranged alternately;

[0026] locally removing the first doped material layer covering the first doped region to form a mark point, and removing the first doped material layer covering the second doped region, wherein the mark point is located inside an outer contour line of the first doped region;

[0027] forming a second doped material layer on a first side of the substrate, removing portions of the second doped material layer corresponding to the first doped region and an isolation region by positioning the mark point, the isolation region being a region of the second doped region adjacent to the first doped region, the second doped material layer being opposite in doping type to the first doped material layer.

[0028] In some embodiments, the first doped material layer comprises a first base layer and a first oxide material layer covering the first base layer;

[0029] The step of locally removing the first doped material layer covering the first doped region to form a mark point, and removing the first doped material layer covering the second doped region specifically comprises:

[0030] laser removing portions of the first oxide material layer corresponding to the second doped region, and laser removing portions of the first oxide material layer corresponding to a preset region on the first doped region to locally expose the first base layer;

[0031] removing the exposed region of the first base layer by a wet chemical method.

[0032] In some embodiments, the second doped material layer comprises a second base layer and a second oxide material layer covering the second base layer;

[0033] The step of removing portions of the second doped material layer corresponding to the first doped region and an isolation region by positioning the mark point specifically comprises:

[0034] laser removing portions of the second oxide material layer corresponding to the first doped region, and laser removing portions of the second oxide material layer corresponding to the isolation region to locally expose the second base layer;

[0035] removing the exposed region of the second base layer by a wet chemical method.

[0036] In some embodiments, the first doped region comprises a metal arrangement region, and the preset region is arranged apart from the metal arrangement region.

[0037] In some embodiments, the providing a substrate specifically comprises: forming a first doped material layer on each surface of a substrate;

[0038] after the step of partially removing the first doped material layer on the first doped region to form a mark point and removing the first doped material layer on the second doped region, and before the step of forming a second doped material layer on the first side of the substrate, further comprises:

[0039] removing the first doped material layer on the surface of the second side of the substrate and the surface of each side, the second side being opposite to the first side, and each side being adjacent to the surface of the first side and the surface of the second side of the substrate.

[0040] In some embodiments, the step of forming a second doped material layer on the first side of the substrate specifically comprises: forming the second doped material layer on the surface of each side of the substrate.

[0041] after the step of removing the part of the second doped material layer corresponding to the first doped region and the isolation region, further comprising: removing the second doped material layer on the surface of the second side of the substrate and the surface of each side by wet chemical method.

[0042] In some embodiments, after the step of removing the part of the second doped material layer corresponding to the first doped region and the isolation region, further comprising:

[0043] forming a first passivation layer on the first side of the substrate;

[0044] forming a first electrode on the first passivation layer corresponding to the position of the first doped region by positioning through the mark point, and forming a second electrode on the first passivation layer corresponding to the position of the second doped region. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of the disclosed drawings.

[0046] Fig. 1 is a structural schematic diagram of a solar cell provided by an embodiment of the present application.

[0047] Fig. 2 is a structural schematic diagram of a first electrode and a second electrode in a solar cell provided by an embodiment of the present application.

[0048] Fig. 3 is a flow schematic diagram of a manufacturing method of a solar cell provided by an embodiment of the present application.

[0049] Fig. 4 is a structural schematic diagram of a substrate in a manufacturing method of a solar cell provided by an embodiment of the present application.

[0050] Figure 5 is a schematic diagram of forming a mark point in the method for manufacturing a solar cell according to an embodiment of the present application.

[0051] Figure 6 is a schematic diagram of removing the part of the second doping material layer corresponding to the second doping region and the isolation region by positioning through the mark point in the method for manufacturing a solar cell according to an embodiment of the present application.

[0052] BRIEF DESCRIPTION OF DRAWINGS 100, solar cell; 101, substrate; 10, base; 20, first doping pattern; 201, first doping material layer; 30, second doping pattern; 301, second doping material layer; 40, insulating isolation groove; 50, mark point; 60, first passivation layer; 70, second passivation layer; 80, first electrode; 81, first main grid; 82, first sub-grid; 90, second electrode; 91, second main grid; 92, second sub-grid; F, first side; S, second side; R, first doping region; Y, second doping region; G, isolation region. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0054] It should be understood that the terms "comprising", "including", "having", "containing", and any other similar terms used in the present application are taken to be inclusive or open-ended and not exclusive or limiting, unless expressly specified or limited otherwise.

[0055] In some cases, a single embodiment can incorporate multiple features for the sake of brevity and / or to aid in understanding the scope of the present disclosure. It is to be understood that, in such cases, the multiple features can be provided separately (e.g., in different embodiments) or in any other suitable combination. Conversely, when different features are described in different embodiments, these different features can be combined into a single embodiment, unless otherwise stated or implied, unless otherwise stated or implied. This principle applies equally to the claims, which can be recombined in any combination, i.e., any claim can be modified to include any feature defined in another claim.

[0056] In this application, the phrase "at least one of" followed by a listing of a group of items means any one single item including members from within the listed group, or a combination of two or more of the listed items. For example, "at least one of a, b, and c" means "a" alone, "b" alone, "c" alone, "a and b", "a and c", "b and c", or "a and b and c". It is also to be noted that, as used in this application, the singular form "a", "an", and "the" include plural references unless the context clearly dictates otherwise.

[0057] In the description of the present application, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like mean the orientation or positional relationship shown in the drawings based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0058] In addition, the terms "first", "second", "third", etc. are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0059] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be broadly understood, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0060] In the present application, unless otherwise specifically defined and limited, the first feature "on" or "under" the second feature can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0061] It is to be noted that when an element is referred to as being "on" or "connected to" another element, it can be directly on the other element or intervening elements can also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can also be present. The terms "vertical", "horizontal", "upper", "lower", "left", "right", and the like as used herein are used for illustration only and are not intended to be limiting.

[0062] The solar cell and the manufacturing method thereof according to the embodiments of the present application will be described below with reference to the accompanying drawings. It should be noted that the solar cell according to the embodiments of the present application is exemplified by a conventional back contact solar cell, and the solar cell can also be set as other types of cells according to actual requirements, for example, TBC, HBC type solar cells, and the like. For the solar cell of other types, similar descriptions are not repeated here.

[0063] Referring to FIG. 1, the first aspect of the embodiments of the present application provides a solar cell 100, which comprises a substrate 10, a doped layer, the doped layer comprising a first doped pattern 20 and a second doped pattern 30.

[0064] The first doped pattern 20 and the second doped pattern 30 are alternately arranged along a preset direction on the surface of the first side F of the substrate 10, and an insulating isolation groove 40 is configured between each adjacent first doped pattern 20 and second doped pattern 30. The surface of the first side F of the substrate 10 is further provided with a mark point 50. The mark point 50 is located inside the outer contour line of the first doped pattern 20, and is used as a positioning reference in the process of forming the second doped pattern 30. The mark point 50 can be distinguished from the first doped pattern 20 and the second doped pattern 30 on an optical image, for example.

[0065] In the embodiments of the present application, the mark point 50 is arranged at a position corresponding to the first doped pattern 20, and the mark point 50 is located inside the outer contour line of the first doped pattern 20. That is, the mark point 50 is completely located in the first doped pattern 20. In the top-down direction facing the first side F, the mark point 50 is separated from the outer contour line of the first doped pattern 20 by a certain distance. Since the first doped pattern 20 and the second doped pattern 30 are alternately arranged, the mark point 50 is also insulated from the second doped pattern 30 by the insulating isolation groove 40, so that the mark point 50 is not easily confused with the outer contour lines of the first doped pattern 20 and the second doped pattern 30, and the positioning accuracy is high, and the yield of solar cell production is also improved.

[0066] The first doped pattern 20 is a doped semiconductor material, which can include one or more of doped monocrystalline silicon, doped polycrystalline silicon, and doped amorphous silicon. The second doped pattern 30 is also a doped semiconductor material, which can include one or more of doped monocrystalline silicon, doped polycrystalline silicon, and doped amorphous silicon. The doping type of the second doped pattern 30 is opposite to that of the first doped pattern 20. For example, the first doped pattern 20 is P-type doped, and the second doped pattern 30 is N-type doped, or the first doped pattern 20 is N-type doped, and the second doped pattern 30 is P-type doped.

[0067] In some embodiments, the solar cell 100 further includes a first passivation layer 60, first electrodes 80, and second electrodes 90, which are arranged alternately and spaced apart from each other.

[0068] The first passivation layer 60 is arranged on the surface of the doped layer away from the substrate 10. The first electrodes 80 are arranged on the first passivation layer 60 at positions corresponding to the first doped pattern 20 and in ohmic contact with the first doped pattern 20. The second electrodes 90 are arranged on the first passivation layer 60 at positions corresponding to the second doped pattern 30 and in ohmic contact with the second doped pattern 30. The mark point 50 is arranged spaced apart from both the first electrodes 80 and the second electrodes 90. In this way, when the first electrodes 80 and the second electrodes 90 are subsequently manufactured by screen printing or the like, the mark point 50 will not be confused with the edge profile of the first electrodes 80 and the second electrodes 90, so that the positioning accuracy is higher.

[0069] In some embodiments, the first electrodes 80 include a plurality of first main grids 81 and first sub-grids 82, and each first main grid 81 is connected with a plurality of first sub-grids 82. The second electrodes 90 include a plurality of second main grids 91 and second sub-grids 92, and each second main grid 91 is connected with a plurality of second sub-grids 92. The plurality of first main grids 81 and the plurality of second main grids 91 can be arranged alternately. The plurality of first sub-grids 82 and the plurality of second sub-grids 92 can be arranged alternately.

[0070] The number of the first electrodes 80 and the second electrodes 90 arranged on the solar cell 100 can be set as needed, and only the layout of an adjacent first electrode 80 and an adjacent second electrode 90 is shown in FIG. 2. In some embodiments, as shown in FIG. 2, the mark point 50 is located on the side of the first sub-grid 82 extending towards the second main grid 91. The length of the first sub-grid 82 arranged corresponding to the mark point 50 is appropriately shortened to avoid the mark point 50.

[0071] Alternatively, in other embodiments, the mark point 50 can also be located on the side of the second sub-grid 92 extending towards the first main grid 81. The length of the second sub-grid 92 arranged corresponding to the mark point 50 is appropriately shortened to avoid the mark point 50.

[0072] In some embodiments, with continued reference to FIG. 1, the mark point 50 is a groove structure formed on the first doped pattern 20. The groove structure as the mark point 50 can be disposed completely in one first doped pattern 20.

[0073] In combination with FIG. 1, FIG. 3 and FIG. 4, the method for manufacturing the solar cell provided by the embodiments of the present application can be used to manufacture the solar cell described above.

[0074] The method comprises:

[0075] S10, providing a substrate 101, the substrate 101 comprising a substrate 10 and a first doped material layer 201 disposed on a surface of a first side F of the substrate 10, the surface of the first side F having first doped regions R and second doped regions Y arranged alternately.

[0076] The first doped regions R correspond to regions of the solar cell 100 where the first doped pattern 20 and the insulating isolation groove 40 are to be formed, and the second doped regions Y correspond to regions of the solar cell 100 where the second doped pattern 30 is to be formed.

[0077] S20, partially removing the first doped material layer 201 covering the first doped regions R to form mark points 50, and removing the first doped material layer 201 covering the second doped regions Y, wherein the mark points 50 are located inside the outer contour line of the first doped regions R.

[0078] Referring to FIG. 5, in some embodiments, after the mark points 50 are formed, the surface of the substrate 10 is exposed outside from the mark points 50. The mark points 50 are located inside the outer contour line of the first doped regions R, which means that in the top-down direction facing the first side F, the mark points 50 are located in the first doped regions R and are not adjacent to the outer edge of the first doped regions R, and there is a certain interval between the mark points 50 and the outer edge of the first doped regions R.

[0079] S30, forming a second doped material layer 301 on the first side F of the substrate 10, positioning by grabbing the mark points 50, removing the part of the second doped material layer 301 corresponding to the first doped regions R and the isolation regions G, the isolation regions G being the regions of the second doped regions Y adjacent to the first doped regions R, and the second doped material layer 301 being opposite in doping type to the first doped material layer 201.

[0080] Referring to FIG. 6, in S30, the second doped material layer 301 in the isolation regions G and in the mark points 50 is also removed.

[0081] Since the first doped material layer 201 covering the first doped region R is partially removed to form the mark point 50, the mark point 50 is located inside the outer contour line of the first doped region R, thus in the top-down direction facing the first side F, the mark point 50 is spaced apart from the outer contour line of the first doped region R, and the mark point 50 is completely located in the first doped region R. The first doped material layer 201 covering the second doped region Y is removed, and the first doped material layer 201 covering the first doped region R is retained, so that the mark point 50 is located inside the outer contour of the retained first doped material layer 201 on the first doped region R and does not mix with the outer contour of the retained first doped material layer 201. The first doped region R and the second doped region Y are arranged alternately, and the mark point 50 is located inside the outer contour line of the first doped region R, so that the mark point 50 is naturally separated from the second doped region Y.

[0082] In the related art, the mark point can be formed at the edge position of the first doped region, and the mark point is easy to mix with the contour line of the first doped region. In the scheme of the embodiment of the present application, in the step of removing the part of the second doped material layer 301 corresponding to the first doped region R and the isolation region G by positioning through grabbing the mark point 50, since the mark point 50 is located inside the outer contour of the retained first doped material layer 201 on the first doped region R, the mark point 50 is not easy to mix with the outer contour line of the retained first doped material layer 201, so that the positioning accuracy is higher, and the yield of the solar cell 100 production is improved.

[0083] In some embodiments, the first doped material layer 201 includes a first base layer and a first oxide material layer covering the first base layer. The first base layer may, for example, be a P-type or N-type polycrystalline silicon doped conductive layer, and the first oxide material layer may, for example, be borosilicate glass or phosphosilicate glass.

[0084] In some embodiments, in step S20, the step of partially removing the first doped material layer 201 covering the first doped region R to form the mark point 50 and removing the first doped material layer 201 covering the second doped region Y includes:

[0085] Performing laser removal on the part of the first oxide material layer corresponding to the second doped region Y and performing laser removal on the part of the first oxide material layer corresponding to the preset region on the first doped region R to partially expose the first base layer;

[0086] Removing the exposed region of the first base layer 2011 by a wet chemical method.

[0087] When the exposed areas of the first base layer 2011 are removed by the wet chemical method, the first base layer 2011 at the preset area position is also removed, and the surface of the substrate 10 is exposed, thereby forming the mark point 50. The remaining part on the first doped region R will form the first doped pattern 20 in the subsequent process.

[0088] In the step of forming the second doped material layer 301 on the first side F of the substrate 10, the second doped material layer 301 covers the second doped region Y of the substrate 10, covers the first doped material layer 201 on the first doped region R, and fills into the mark point 50.

[0089] In some embodiments, the second doped material layer 301 includes a second base layer and a second oxide material layer covering the second base layer.

[0090] In some embodiments, in the step S30, the step of removing the part of the second doped material layer 301 corresponding to the first doped region R and the isolation region G by positioning the mark point 50 specifically includes:

[0091] The part of the second oxide material layer corresponding to the first doped region R is removed by laser, and the part of the second oxide material layer corresponding to the isolation region G is removed by laser to locally expose the second base layer. At this time, the second base layer covering the isolation region G is removed, and the second base layer corresponding to the first doped region R is also removed, as shown in FIG. 6. In some embodiments, after the above wet chemical step, the method further includes removing the second oxide material layer on the second doped region Y, and the remaining second base layer forms the second doped pattern 30.

[0092] In some embodiments, the first doped region R domain includes a metal setting region, and the preset area where the mark point 50 is to be formed is arranged apart from the metal setting region where the first electrode 80 is to be formed.

[0093] In this way, after the first electrode 80 is formed on the metal setting region, the first electrode 80 and the mark point 50 are spaced apart, and when the mark point 50 is grabbed, the first electrode 80 will not affect the grabbing of the mark point 50.

[0094] In some embodiments, the substrate 101 can have the first doped material layer 201 formed on each surface, or can refer to FIG. 4, and only the surface of the first side F has the first doped material layer 201 formed thereon.

[0095] When the substrate 101 has the first doped material layer 201 formed on each surface, the substrate 101 is provided by forming the first doped material layer 201 on each surface of the substrate 10.

[0096] In some embodiments, after the step of removing the first doped material layer 201 on the second side S and the side surfaces of the substrate 10, the method further comprises:

[0097] The first doped material layer 201 on the surface of the second side S and the side surfaces of the substrate 10 is removed, the second side S is opposite to the first side F, and the side surfaces are between the surface of the first side F and the surface of the second side S of the substrate 10.

[0098] The first doped material layer 201 on the second side S and the side surfaces of the substrate 10 can be removed by wet chemical method. In this way, the surface of the second side S of the substrate 10 is exposed.

[0099] In some embodiments, the step of forming the second doped material layer 301 on the first side F of the substrate 10 specifically comprises: forming the second doped material layer 301 on the surface of each side of the substrate 10.

[0100] In some embodiments, after the step of removing the part of the second doped material layer 301 corresponding to the first doped region R and the isolation region G in step S30, the method further comprises: removing the second doped material layer 301 on the surface of the second side S and the side surfaces of the substrate 10 by wet chemical method.

[0101] In some embodiments, after the step of removing the part of the second doped material layer 301 corresponding to the first doped region R and the isolation region G, the method of manufacturing the solar cell further comprises:

[0102] Forming a first passivation layer 60 on the first side F of the substrate 10.

[0103] In some embodiments, the method of manufacturing the solar cell further comprises: positioning by grabbing the mark point 50, forming a first electrode 80 on the first passivation layer 60 corresponding to the position of the first doped region R, and forming a second electrode 90 on the first passivation layer 60 corresponding to the position of the second doped region Y.

[0104] Of course, after the first passivation layer 60 is formed on the first side F of the substrate 10, a second passivation layer 70 can also be formed on the second side S of the substrate 10. The method of forming the first electrode 80 and the second electrode 90 can be screen printing. In specific implementation, the number of mark points 50 can be four, and the screen printing equipment can have four cameras to take pictures of the four mark points 50. The center of the substrate 10 is positioned by using the four mark points 50, so as to fine-tune the position of the substrate 10 and ensure the accuracy requirement.

[0105] Both the first passivation layer 60 and the second passivation layer 70 can be composite films of single or multiple films such as silicon nitride, aluminum oxide, titanium oxide, silicon oxide, and silicon oxynitride.

[0106] The following describes a specific example of a method for manufacturing a solar cell according to an embodiment of this application. The method includes:

[0107] Step 1: Prepare a first doped material layer 201 on each surface of the substrate 10. The first doped material layer 201 is a doped semiconductor layer, including one or more of doped single-crystal silicon, doped polycrystalline silicon, and doped amorphous silicon.

[0108] Step 2: On the surface of the first side F of the substrate, use a laser device to perform patterning processing to remove the local area (corresponding to the position of the four marked points) of the first oxide material layer covering the first doped region R and the first oxide material layer covering the second doped region Y, so as to expose the underlying first substrate layer.

[0109] Step 3: Then, perform wet chemical treatment on the laser-treated areas to remove the first substrate layer on the second doped region Y and the first substrate layer on the first doped region R corresponding to the marked points (the exposed portion of the first substrate layer), thus exposing the substrate 10. At this point, four marked points 50 are formed. Then, remove the first doped material layer 201 from the side surfaces and the second side S of the substrate 10, as shown in Figure 5. Of course, the step of removing the first doped material layer 201 from the side surfaces and the second side S of the substrate 10 can also be done after step 1 and before step 2.

[0110] Step 4: Prepare a second doped material layer 301 (including a second substrate layer and a second oxide material layer) on each surface of the structure formed in Step 3. The second doped material layer 301 is a doped semiconductor layer, including one or more of doped single-crystal silicon, doped polycrystalline silicon, and doped amorphous silicon. The doping type of the second doped material layer 301 is opposite to that of the first doped material layer 201. The first doped material layer 201 is P-type doped or N-type doped, and the second doped material layer 301 is N-type doped or P-type doped.

[0111] Step 5: Use the four markers 50 mentioned above to perform four-point positioning using a laser device.

[0112] Laser processing is performed on the isolation region G (width 10-200μm) at the boundary with the first doped region R in the second doped region Y to remove the second oxide material layer at the boundary. Laser processing is also performed on the first doped region R to remove the second oxide material layer corresponding to the first doped region R.

[0113] The first side F and the second side S are treated using a wet chemical method. During this process, on the first side F, the second substrate layer of the isolation region G is completely removed, exposing the substrate 10. The second substrate layer corresponding to the first doped region R is also completely removed, and the first oxide material layer in the first doped material layer 201 of the first doped region R is also removed, exposing the first substrate layer, thereby forming a first doped pattern 20 on the second doped region R. In the second doped material layer 301 covering the second doped region Y, the second oxide material layer is removed, leaving the second substrate layer to form the second doped pattern 30.

[0114] On the second side S and the side surface, the second doped material layer 301 is removed using a wet chemical method.

[0115] The surface morphology of the isolation region G can be a polished surface, a textured surface with randomly distributed pyramidal shapes at the micrometer level, or an etched pit or a non-polished uneven surface. After wet chemical treatment, the surface of the second side S of the substrate 10 can be a polished surface, a textured surface with randomly distributed pyramidal shapes at the micrometer level, or an etched pit or a non-polished uneven surface.

[0116] Step 6: A first passivation layer 60 and a second passivation layer 70 are respectively disposed on the first side F and the second side S of the substrate, as shown in Figure 1.

[0117] Step 7: The second electrode 90 and the first electrode 80 are respectively set on the second doped region Y and the first doped region R through four marking points to form a solar cell as shown in Figure 1.

[0118] 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.

[0119] 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, The solar cell comprises: a substrate; a doped layer comprising a first doped pattern and a second doped pattern arranged alternately on a surface of a first side of the substrate along a preset direction, and an insulating isolation groove being formed between each adjacent first doped pattern and second doped pattern; wherein the surface of the first side of the substrate is further provided with a mark point, the mark point is located inside an outer contour line of the first doped pattern, and is used as a positioning reference in a process of forming the second doped pattern. The solar cell further comprises:

2. The solar cell according to claim 1, characterized in that, a first passivation layer provided on a surface of the doped layer away from the substrate; a first electrode provided on the first passivation layer at a position corresponding to the first doped pattern and in ohmic contact with the first doped pattern, and a second electrode provided on the first passivation layer at a position corresponding to the second doped pattern and in ohmic contact with the second doped pattern; the mark point is arranged separately from the first electrode and the second electrode. The first electrode comprises a plurality of first main grids and first sub-grids, each first main grid being connected with a plurality of first sub-grids correspondingly; the second electrode comprises a plurality of second main grids and second sub-grids, each second main grid being connected with a plurality of second sub-grids correspondingly; 3. The solar cell according to claim 2, characterized in that, the plurality of first sub-grids and the plurality of second sub-grids are arranged alternately; the mark point is located on a side of the second sub-grids in an extension direction of the second sub-grids and towards the first main grid, or the mark point is located on a side of the first sub-grids in an extension direction of the first sub-grids and towards the second main grid. The mark point is arranged separately from an end of the second sub-grids in the extension direction of the second sub-grids and towards the first main grid, or the mark point is arranged separately from an end of the first sub-grids in the extension direction of the first sub-grids and towards the second main grid.

4. The solar cell according to claim 3, characterized in that, The mark point is arranged separately from the first electrode and the second electrode.

5. The solar cell according to any one of claims 2 to 4, characterized in that, The mark point is a groove structure formed on the first doped pattern.

6. The solar cell according to any one of claims 1 to 5, characterized in that, The mark point can be distinguished from the first doped pattern and the second doped pattern on an optical image.

7. The solar cell according to any one of claims 1 to 6, characterized in that, The solar cell comprises:

8. A solar cell, characterized by, a substrate; a doped layer comprising a first doped pattern and a second doped pattern arranged alternately on a surface of a first side of the substrate along a preset direction, and an insulating isolation groove being formed between each adjacent first doped pattern and second doped pattern; wherein the surface of the first side of the substrate is further provided with a mark point, the mark point is located inside an outer contour line of the first doped pattern. The mark point can be distinguished from the first doped pattern and the second doped pattern on an optical image. The method comprises:

9. The solar cell of claim 8, wherein, providing a substrate comprising a substrate and a first doped material layer provided on a surface of a first side of the substrate, the surface of the first side having first doped regions and second doped regions arranged alternately; 10. A method for manufacturing a solar cell, characterized in that, partially removing the first doped material layer covering the first doped regions to form a mark point, and removing the first doped material layer covering the second doped regions, wherein the mark point is located inside an outer contour line of the first doped regions; ​ ​ forming a second doped material layer on a first side of the substrate, removing portions of the second doped material layer corresponding to the first doped regions and isolation regions by grabbing the marker points, the isolation regions being regions of the second doped regions adjacent to the first doped regions, the second doped material layer being of an opposite doping type to the first doped material layer.

11. The method of producing a solar cell according to claim 10, wherein The first doped material layer comprises a first base layer and a first oxide material layer covering the first base layer. The step of partially removing the first doped material layer covering the first doped regions to form marker points and removing the first doped material layer covering the second doped regions comprises: laser removing portions of the first oxide material layer corresponding to the second doped regions and laser removing portions of the first oxide material layer corresponding to predetermined regions on the first doped regions to partially expose the first base layer; removing the exposed regions of the first base layer by wet chemical method.

12. The method of producing a solar cell according to claim 11, wherein The second doped material layer comprises a second base layer and a second oxide material layer covering the second base layer. The step of removing portions of the second doped material layer corresponding to the first doped regions and isolation regions by grabbing the marker points comprises: laser removing portions of the second oxide material layer corresponding to the first doped regions and laser removing portions of the second oxide material layer corresponding to the isolation regions to partially expose the second base layer; removing the exposed regions of the second base layer by wet chemical method.

13. The method of producing a solar cell according to claim 11 or 12, wherein The first doped regions comprise metal disposed regions, and the predetermined regions are arranged apart from the metal disposed regions.

14. The method of producing a solar cell according to any one of claims 10 to 13, wherein The providing the substrate comprises forming a first doped material layer on each surface of the substrate. After the step of partially removing the first doped material layer covering the first doped regions to form marker points and removing the first doped material layer covering the second doped regions, the step of forming a second doped material layer on a first side of the substrate further comprises: removing the first doped material layer on the surface of the second side of the substrate and each side surface of the substrate, the second side being arranged opposite to the first side, and each side surface being adjacent to the surface of the first side and the surface of the second side of the substrate.

15. The method of producing a solar cell according to claim 14, wherein The step of forming a second doped material layer on a first side of the substrate comprises forming the second doped material layer on each side surface of the substrate. After the step of removing portions of the second doped material layer corresponding to the first doped regions and isolation regions, the method further comprises removing the second doped material layer on the surface of the second side of the substrate and each side surface of the substrate by wet chemical method.

16. The method of producing a solar cell according to any one of claims 10 to 15, wherein After the step of removing portions of the second doped material layer corresponding to the first doped regions and isolation regions, the method further comprises: forming a first passivation layer on the first side of the substrate; The first electrode is formed on the first passivation layer at a position corresponding to the first doped region by positioning through grabbing the mark point, and the second electrode is formed on the first passivation layer at a position corresponding to the second doped region.

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