Hybrid heterojunction solar cell, preparation method thereof and cell module

Abstract

The invention relates to the technical field of solar cells, in particular to a hybrid heterojunction solar cell, a preparation method thereof and a cell module. The hybrid heterojunction solar cell comprises a semiconductor substrate which is provided with a light receiving surface and a backlight surface which are opposite to each other; the phosphorus diffusion layer is arranged on the light receiving surface of the semiconductor substrate; the first tunneling oxide layer is arranged on the surface, away from the semiconductor substrate, of the phosphorus diffusion layer; the electron transport layer is arranged on the surface, far away from the semiconductor substrate, of the first tunneling oxide layer; and the antireflection layer is arranged on the surface, far away from the semiconductor substrate, of the electron transmission layer. The phosphorus diffusion layer is arranged on the light receiving surface of the substrate to serve as a front surface field passivation layer and cooperates with the electron transmission layer, the passivation effect is further enhanced, meanwhile, the tunneling oxide layer is used for replacing intrinsic amorphous silicon to complete substrate surface passivation, the electron transmission layer is combined with the antireflection layer, and the passivation effect is improved. And the light absorption of the non-metal region of the cell is reduced while the passivation performance is maintained.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a hybrid heterojunction solar cell and a preparation method and a cell assembly thereof. Background Art

[0002] In recent years, photovoltaic industrialization technology has developed rapidly, and each manufacturing link has undergone technological updates. New technologies and processes bring lower costs and better product performance. Heterojunction cells have a series of advantages such as high conversion efficiency, fewer manufacturing processes, and thin-film applications. The theoretical efficiency of heterojunction cells (HJT cells) is at a relatively high level among single-crystal silicon cell structures, and is expected to become the mainstream choice for large-scale mass production in the future; however, HJT cells use an amorphous silicon / microcrystalline silicon structure for passivation. While this structure brings excellent passivation performance, it is also more susceptible to ultraviolet radiation, resulting in ultraviolet radiation-induced attenuation on the surface, resulting in the power generation performance of the components being lower than expected.

[0003] Some existing technologies use cut-off films to filter ultraviolet rays, but ultraviolet rays are useful energy that can be absorbed by crystalline silicon cells and converted into electrical energy. The cut-off film makes the initial power of the component low; there are also technologies that use UV light transfer film solutions, but the reliability of the light transfer film has yet to be verified, and the light transfer film will cause the appearance of the component to be blue, which does not conform to the industry's aesthetic preference for black; there are also some technical solutions that grow a single layer of doped polysilicon layer in some cells, and then locally etch it to form a thin doped polysilicon layer structure in the non-metallic area to reduce the light absorption of the polysilicon layer. Due to the large number of pinhole-like holes in amorphous silicon, the etching speed is difficult to control, and the process stability is poor in the mass production stage, which increases the difficulty of production. Therefore, there are still many deficiencies in the surface design of heterojunction cells in this field. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art to at least a certain extent. To this end, the present invention provides a hybrid heterojunction solar cell and a preparation method and a battery assembly thereof. The hybrid heterojunction solar cell uses a tunneling oxide layer to replace the intrinsic amorphous silicon in the traditional heterojunction battery structure to complete the substrate surface passivation, and combines the electron transport layer with the anti-reflection layer to maintain the passivation performance while reducing the light absorption of the non-metallic area of ​​the battery and reducing UV attenuation. At the same time, the double-sided intrinsic amorphous silicon and the front and back doped amorphous silicon in the traditional heterojunction solar cell require relatively high-cost plasma enhanced chemical vapor deposition (PECVD) equipment to complete the preparation. Compared with it, the present invention reduces the production cost and the complexity of the preparation process.

[0005] To this end, the first aspect of the present invention provides a hybrid heterojunction solar cell, comprising:

[0006] A semiconductor substrate, wherein the semiconductor substrate has a light-receiving surface and a light-receiving surface opposite to each other;

[0007] A phosphorus diffusion layer is disposed on the light receiving surface of the semiconductor substrate;

[0008] A first tunneling oxide layer is disposed on a surface of the phosphorus diffusion layer away from the semiconductor substrate;

[0009] An electron transport layer is disposed on a surface of the first tunneling oxide layer away from the semiconductor substrate;

[0010] The anti-reflection layer is disposed on the surface of the electron transport layer away from the semiconductor substrate.

[0011] In order to solve the deficiencies in the prior art, the inventors set a phosphorus diffusion layer as a front surface field passivation layer on the light-receiving surface of the substrate, which cooperates with the electron transport layer to further enhance the passivation effect. At the same time, a tunneling oxide layer is used to replace the intrinsic amorphous silicon in the traditional heterojunction battery structure to complete the substrate surface passivation. The electron transport layer is combined with the anti-reflection layer. Compared with the doped microcrystalline silicon structure or the intrinsic amorphous silicon structure set on the light-receiving surface of the conventional heterojunction solar cell substrate, it has better passivation performance and reduces UV attenuation. At the same time, the use of doped microcrystalline silicon structure or intrinsic amorphous silicon structure is reduced, thereby reducing the production cost and the complexity of the preparation process.

[0012] According to an embodiment of the present invention, the thickness of the phosphorus diffusion layer is 50nm-500nm.

[0013] According to an embodiment of the present invention, the material of the first tunneling oxide layer includes silicon oxide.

[0014] According to an embodiment of the present invention, the thickness of the first tunneling oxide layer is 0.5 nm-2 nm.

[0015] According to an embodiment of the present invention, the material of the electron transport layer includes at least one of aluminum-doped zinc oxide, gallium-doped zinc oxide, aluminum-gallium co-doped zinc oxide or zinc oxide.

[0016] According to an embodiment of the present invention, the thickness of the electron transport layer is 10 nm-40 nm.

[0017] According to an embodiment of the present invention, the material of the anti-reflection layer includes silicon nitride and / or silicon oxynitride.

[0018] According to an embodiment of the present invention, the thickness of the anti-reflection layer is 30nm-60nm.

[0019] According to an embodiment of the present invention, the hybrid heterojunction solar cell further includes:

[0020] A second tunneling oxide layer is disposed on the backlight surface of the semiconductor substrate;

[0021] A doped semiconductor layer is disposed on a surface of the second tunneling oxide layer away from the semiconductor substrate;

[0022] The conductive layer is disposed on a surface of the doped semiconductor layer away from the semiconductor substrate.

[0023] According to an embodiment of the present invention, the hybrid heterojunction solar cell further satisfies at least one of the following conditions:

[0024] The material of the second tunneling oxide layer includes silicon oxide;

[0025] The thickness of the second tunneling oxide layer is 0.5nm-2nm;

[0026] The material of the doped semiconductor layer includes boron-doped amorphous silicon and / or boron-doped microcrystalline silicon;

[0027] The thickness of the doped semiconductor layer is 10nm-50nm;

[0028] The material of the conductive layer includes at least one of indium oxide, tin oxide and zinc oxide;

[0029] The thickness of the conductive layer is 70nm-120nm.

[0030] The second aspect of the present invention provides a method for preparing the hybrid heterojunction solar cell according to the first aspect, comprising:

[0031] Providing a semiconductor substrate, wherein the semiconductor substrate has a light-receiving surface and a light-receiving surface opposite to each other;

[0032] A phosphorus diffusion layer, a first tunneling oxide layer, an electron transport layer and an anti-reflection layer are sequentially formed on the light-receiving surface of the semiconductor substrate.

[0033] According to the preparation method of the hybrid heterojunction solar cell of the present invention, a phosphorus diffusion layer is prepared on the light-receiving surface of the substrate as a front surface field passivation layer, which cooperates with the electron transport layer to further enhance the passivation effect, and a tunneling oxide layer is used to replace the intrinsic amorphous silicon in the traditional heterojunction cell structure to complete the substrate surface passivation. At the same time, the tunneling oxide layer is used to replace the conventional intrinsic amorphous silicon layer and the doped microcrystalline silicon layer, which has better passivation performance, and the electron transport layer and the anti-reflection layer are combined to reduce UV attenuation. At the same time, compared with the traditional preparation method, the preparation method provided by the present invention reduces the use of doped microcrystalline silicon structure or intrinsic amorphous silicon structure, reduces the production cost and the complexity of the preparation process.

[0034] According to an embodiment of the present invention, it also includes:

[0035] A second tunneling oxide layer, a doped semiconductor layer and a conductive layer are sequentially formed on the backlight surface of the semiconductor substrate.

[0036] A third aspect of the present invention provides a battery assembly, comprising the hybrid heterojunction solar cell described in the first aspect, or a hybrid heterojunction solar cell prepared according to the preparation method described in the second aspect.

[0037] The battery assembly has better performance by adopting a hybrid heterojunction solar cell with good passivation performance, reduced UV attenuation, simple preparation and low cost.

[0038] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0040] Figure 1 One of the structural schematic diagrams of the hybrid heterojunction solar cell provided by the present invention is shown;

[0041] Figure 2 The second schematic diagram of the structure of the hybrid heterojunction solar cell provided by the present invention is shown;

[0042] Figure 3 The third structural schematic diagram of the hybrid heterojunction solar cell provided by the present invention is shown;

[0043] Figure 4 The fourth structural schematic diagram of the hybrid heterojunction solar cell provided by the present invention is shown;

[0044] Figure 5 The fifth structural schematic diagram of the hybrid heterojunction solar cell provided by the present invention is shown;

[0045] Figure 6 The sixth structural schematic diagram of the hybrid heterojunction solar cell provided by the present invention is shown.

[0046] Reference numerals:

[0047] A hybrid heterojunction solar cell 100 includes a semiconductor substrate 101, a light-receiving surface 1011, a backlight surface 1012, a phosphorus diffusion layer 102, a first tunneling oxide layer 103, an electron transport layer 104, an anti-reflection layer 105, a second tunneling oxide layer 106, a doped semiconductor layer 107, a conductive layer 108, a positive metal electrode 109, and a back metal electrode 110. DETAILED DESCRIPTION

[0048] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0049] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there is no intervening element or layer. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present disclosure, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part. And when the second element, component, region, layer or part is discussed, it does not mean that the present disclosure necessarily has the first element, component, region, layer or part.

[0050] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0051] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0052] In order to make the present invention more easily understood, certain technical and scientific terms are specifically defined below. Unless otherwise clearly defined elsewhere in this document, all other technical and scientific terms used herein have the meanings commonly understood by those skilled in the art to which the present invention belongs.

[0053] In this document, the terms “include” or “comprising” are open expressions, that is, including the contents specified in the present invention but not excluding other contents.

[0054] As used herein, the terms "optionally", "optional" or "optionally" generally mean that the subsequently described event or circumstance may but need not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.

[0055] In the related art, in order to obtain a more stable passivation effect on the battery surface and reduce the light absorption of the non-metallic area of ​​the battery, a sacrificial layer is generally prepared on the electron transport layer, and the sacrificial layer is etched away after annealing to retain the conductive passivation contact structure. However, this method adds an etching step, and the sacrificial layer is completely removed in the subsequent steps, and its material consumption is high. In addition, multiple composite layers are set on the front side of the substrate to obtain a stable passivation effect on the battery surface while reducing the light absorption of the non-metallic area of ​​the battery, but this method is more complicated and also involves the step of etching with an acid solution, which is not conducive to large-scale production.

[0056] The present invention proposes a hybrid heterojunction solar cell and a preparation method and a battery assembly thereof. The hybrid heterojunction solar cell uses a tunneling oxide layer to replace the intrinsic amorphous silicon in the traditional heterojunction battery structure to complete the substrate surface passivation, and an electron transport layer and an anti-reflection layer are arranged on the light-receiving surface, while maintaining the passivation performance, the light absorption of the non-metallic area of ​​the battery is reduced, the surface carrier recombination caused by ultraviolet rays is reduced, and the ultraviolet resistance is more excellent. At the same time, compared with the traditional preparation method, the use of doped microcrystalline silicon structure or intrinsic amorphous silicon structure is reduced, the preparation process is simpler, the cost is lower, and it is more suitable for mass production.

[0057] According to an embodiment of the present invention, a first aspect of the present invention provides a hybrid heterojunction solar cell, the structure of which is shown in FIG. Figure 1-6 .

[0058] According to a specific embodiment of the present invention, the hybrid heterojunction solar cell 100 includes a semiconductor substrate 101 having a light-receiving surface 1011 and a backlight surface 1012 opposite to each other. Figure 1 Specifically, the semiconductor substrate 101 includes single crystal silicon, and its doping type includes N-type or P-type, and N-type is optional. The thickness of the semiconductor substrate is not particularly limited, and those skilled in the art can select it according to actual needs. Furthermore, the light-receiving surface 1011 can be prepared as a velvet structure, such as a pyramid morphology.

[0059] According to a specific embodiment of the present invention, the hybrid heterojunction solar cell 100 further includes a phosphorus diffusion layer 102, which is disposed on the light receiving surface 1011 of the semiconductor substrate 101. Figure 2, which can be used as a front surface field passivation layer. The thickness of the phosphorus diffusion layer 102 is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, the thickness of the phosphorus diffusion layer 102 can be 50nm-500nm, such as 50nm, 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, etc.

[0060] According to a specific embodiment of the present invention, the hybrid heterojunction solar cell 100 further includes a first tunneling oxide layer 103, which is disposed on the surface of the phosphorus diffusion layer 102 away from the semiconductor substrate 101, see Figure 2 . Compared with the doped microcrystalline silicon structure or intrinsic amorphous silicon structure on the light-receiving surface of the substrate of a conventional heterojunction solar cell, it has better passivation performance and can reduce UV attenuation, while reducing the use of doped microcrystalline silicon structure or intrinsic amorphous silicon structure, reducing production costs and the complexity of the preparation process. The material of the first tunneling oxide layer 102 may include a tunneling oxide, such as silicon oxide, and its thickness range is not particularly limited. Those skilled in the art can select it according to actual needs. As some specific examples, the thickness may be 0.5nm-2nm, such as 0.5nm, 1nm, 1.5nm, 2nm, etc.

[0061] According to a specific embodiment of the present invention, the hybrid heterojunction solar cell 100 further includes an electron transport layer 104, which is disposed on a surface of the first tunneling oxide layer 103 away from the semiconductor substrate 101, see Figure 2 The material of the electron transport layer 104 includes but is not limited to aluminum-doped zinc oxide, gallium-doped zinc oxide, aluminum-gallium co-doped zinc oxide or zinc oxide, which has stronger ultraviolet radiation resistance than microcrystalline silicon / amorphous silicon structure. The thickness range is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, the thickness can be 10nm-40nm, such as 10nm, 20nm, 30nm, 40nm, etc.

[0062] According to a specific embodiment of the present invention, the hybrid heterojunction solar cell 100 further includes an anti-reflection layer 105, which is disposed on the surface of the electron transport layer 104 away from the semiconductor substrate 101, see Figure 2 The material of the anti-reflection layer 105 includes but is not limited to silicon nitride and silicon oxynitride. The thickness range thereof is not particularly limited and can be selected by those skilled in the art according to actual needs. As some specific examples, the thickness can be 30nm-60nm, such as 30nm, 40nm, 50nm, 60nm, etc.

[0063] According to a specific embodiment of the present invention, the hybrid heterojunction solar cell 100 may further include a second tunneling oxide layer 106 disposed on the backlight surface 1012 of the semiconductor substrate 101, see Figure 3 Specifically, the material of the second tunneling oxide layer 106 may be the same as or different from that of the first tunneling oxide layer 103, and the thickness range thereof is not particularly limited. Persons skilled in the art may select according to actual needs. As some specific examples, the thickness may be 0.5 nm-2 nm, such as 0.5 nm, 1 nm, 1.5 nm, 2 nm, etc. When the material of the second tunneling oxide layer 106 is the same as that of the first tunneling oxide layer 103, the first tunneling oxide layer 103 and the second tunneling oxide layer 106 may be prepared in one step.

[0064] According to a specific embodiment of the present invention, the hybrid heterojunction solar cell 100 may further include a doped semiconductor layer 107, which is disposed on a surface of the second tunneling oxide layer 106 away from the semiconductor substrate 101, see Figure 4 Specifically, the material of the doped semiconductor layer 107 includes but is not limited to boron-doped amorphous silicon and boron-doped microcrystalline silicon. The thickness range is not particularly limited and can be selected by those skilled in the art according to actual needs. As some specific examples, the thickness can be 10nm-50nm, such as 10nm, 20nm, 30nm, 40nm, 50nm, etc.

[0065] According to a specific embodiment of the present invention, the hybrid heterojunction solar cell 100 may further include a conductive layer 108, which is disposed on a surface of the doped semiconductor layer 107 away from the semiconductor substrate 101, see Figure 5 Specifically, the material of the conductive layer 108 includes but is not limited to indium oxide, tin oxide, and zinc oxide. The thickness range is not particularly limited, and those skilled in the art can select according to actual needs. As some specific examples, the thickness can be 70nm-120nm, such as 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, etc.

[0066] According to a specific embodiment of the present invention, the hybrid heterojunction solar cell 100 may further include a front metal electrode 109 and a back metal electrode 110, see Figure 6 The positive metal electrode 109 is disposed on the surface of the electron transport layer 104 away from the semiconductor substrate 101, and the electron transport layer 104 is exposed by etching a portion of the anti-reflection layer 105, and the positive metal electrode 109 is disposed on the exposed electron transport layer 104. The back metal electrode 110 is disposed on the surface of the conductive layer 108 away from the semiconductor substrate 101. The material of the metal electrode is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, it can be silver or silver-clad copper.

[0067] According to an embodiment of the present invention, a second aspect of the present invention provides a method for preparing the hybrid heterojunction solar cell described in the first aspect. The preparation method comprises:

[0068] Step 10, providing a semiconductor substrate 101, wherein the semiconductor substrate has a light-receiving surface 1011 and a backlight surface 1012 opposite to each other;

[0069] Step 20 : forming a phosphorus diffusion layer 102 , a first tunneling oxide layer 103 , an electron transport layer 104 , and an anti-reflection layer 105 in sequence on the light-receiving surface 1011 of the semiconductor substrate 101 .

[0070] According to a specific embodiment of the present invention, before step 10, the process may further include: polishing the light-receiving surface 1011 and the backlight surface 1012 of the semiconductor substrate 101 to remove dirt from the surface of the semiconductor substrate and provide a clean and flat substrate for subsequent processes. The polishing method is not particularly limited, and those skilled in the art may select it according to actual needs. As some specific examples, the semiconductor substrate 101 may be immersed in a polishing liquid to achieve double-sided polishing.

[0071] According to a specific embodiment of the present invention, the light-receiving surface 1011 of the semiconductor substrate 101 can be textured after polishing to form a positive pyramid morphology to increase optical absorption. The texture-making process is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, for example, the semiconductor substrate 101 can be immersed in an alkaline solution containing a texture-making additive to achieve texture-making, or a laser can be used to selectively etch the semiconductor substrate 101 into a pyramid morphology.

[0072] According to a specific embodiment of the present invention, a phosphorus diffusion layer 102 , a first tunneling oxide layer 103 , an electron transport layer 104 , and an anti-reflection layer 105 are sequentially formed on the light-receiving surface 1011 after texturing.

[0073] The phosphorus diffusion layer 102 is not particularly limited, and those skilled in the art may select it according to actual needs. As some specific examples, the phosphorus diffusion layer 102 may be formed on the light receiving surface 1011 of the semiconductor substrate 101 by diffusion of a phosphorus source.

[0074] The preparation method of the first tunnel oxide layer 103 is not particularly limited, and those skilled in the art may select a method according to actual needs. As some specific examples, the first tunnel oxide layer 103 may be prepared by thermal oxidation, wet chemistry, etc.

[0075] The preparation method of the electron transport layer 104 is not particularly limited, and those skilled in the art may select the method according to actual needs. As some specific examples, the electron transport layer 104 may be obtained by atomic layer deposition (ALD).

[0076] The method for preparing the anti-reflection layer 105 is not particularly limited, and those skilled in the art may select the method according to actual needs. As some specific examples, the anti-reflection layer 105 may be prepared by methods such as PECVD.

[0077] According to a specific embodiment of the present invention, the preparation method further includes: sequentially forming a second tunneling oxide layer 106 , a doped semiconductor layer 107 , and a conductive layer 108 on the backlight surface 1012 of the semiconductor substrate 101 .

[0078] The material of the second tunnel oxide layer 106 may be the same as or different from that of the first tunnel oxide layer 103 , preferably the same, that is, the first tunnel oxide layer 103 and the second tunnel oxide layer 106 may be prepared at the same time.

[0079] The preparation method of the doped semiconductor layer 107 and the conductive layer 108 is not particularly limited, and those skilled in the art can select according to actual needs. As some specific examples, the doped semiconductor layer 107 can be obtained by methods such as PECVD, and the conductive layer 108 can be obtained by physical vapor deposition (PVD) and chemical vapor deposition (CVD), specifically by methods such as reactive plasma deposition (RPD).

[0080] According to a specific embodiment of the present invention, the preparation method further includes: arranging a positive metal electrode 109 on the surface of the electron transport layer 104 away from the semiconductor substrate 101, and arranging a back metal electrode 110 on the surface of the conductive layer 108 away from the semiconductor substrate 101. Specifically, the anti-reflection layer 105 can be etched to expose at least a portion of the electron transport layer 104, and the positive metal electrode 109 is arranged on the exposed electron transport layer 104. For example, a partial area of ​​the anti-reflection layer 105 is etched by laser to expose the electron transport layer 104, and a metal electrode is formed by screen printing, the positive metal electrode 109 is in contact with the electron transport layer 104, and the back metal electrode 110 is in contact with the conductive layer 108. The materials of the positive metal electrode 109 and the back metal electrode 110 can be silver or silver-clad copper.

[0081] According to a specific embodiment of the present invention, the preparation method further includes: hydrogen passivation, which can specifically drive the redistribution of hydrogen ions in each layer by light injection to passivate substrate defects.

[0082] According to an embodiment of the present invention, a third aspect of the present invention provides a battery assembly, comprising the hybrid heterojunction solar cell described in the first aspect, or the hybrid heterojunction solar cell obtained according to the preparation method described in the second aspect. The battery assembly has the same or similar beneficial effects as the aforementioned hybrid heterojunction solar cell, which will not be described in detail here.

[0083] The scheme of the present invention will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used are not indicated by the manufacturer and are all conventional products that can be obtained commercially.

[0084] Example 1

[0085] A method for preparing a hybrid heterojunction solar cell comprises the following steps:

[0086] (1) Clean and polish the N-type silicon substrate, and texture the light-receiving surface to form a pyramid morphology on the front side;

[0087] (2) At 900°C, phosphorus is doped on the light-receiving surface of the silicon substrate to form a phosphorus diffusion layer with a thickness of 50 nm;

[0088] (3) depositing a tunneling silicon oxide layer (including a first tunneling silicon oxide layer and a second tunneling silicon oxide layer) on the phosphorus diffusion layer and the backlight surface of the silicon substrate by thermal oxidation, wherein the thickness of the tunneling silicon oxide layer is 1.4 nm;

[0089] (4) depositing an aluminum-doped zinc oxide layer on the first tunneling silicon oxide layer by ALD, the thickness of which is 30 nm;

[0090] (5) depositing a silicon nitride layer on the aluminum-doped zinc oxide layer by PECVD, with a thickness of 40 nm;

[0091] (6) depositing a P-type microcrystalline silicon layer on the second tunneling silicon oxide layer by PECVD, with a thickness of 30 nm;

[0092] (7) depositing an indium tin oxide layer on the P-type microcrystalline silicon layer by PVD or RPD, with a thickness of 80 nm;

[0093] (8) using laser etching of the silicon nitride layer in the metal contact area to expose the aluminum-doped zinc oxide layer;

[0094] (9) forming a metal electrode by screen printing, wherein the front metal electrode contacts the aluminum-doped zinc oxide layer, the back metal electrode contacts the indium tin oxide layer, and the material of the metal electrode is silver or silver-clad copper;

[0095] (10) Use light injection to drive the redistribution of hydrogen ions in each layer and passivate matrix defects.

[0096] Example 2

[0097] A method for preparing a hybrid heterojunction solar cell comprises the following steps:

[0098] (1) Clean and polish the N-type silicon substrate, and texture the light-receiving surface to form a pyramid morphology on the front side;

[0099] (2) At 900°C, phosphorus is doped on the light-receiving surface of the silicon substrate to form a phosphorus diffusion layer with a thickness of 200 nm;

[0100] (3) depositing a tunneling silicon oxide layer (including a first tunneling silicon oxide layer and a second tunneling silicon oxide layer) on the phosphorus diffusion layer and the backlight surface of the silicon substrate by thermal oxidation, with a thickness of 1 nm;

[0101] (4) depositing an aluminum-doped zinc oxide layer on the first tunneling silicon oxide layer by ALD, the thickness of which is 20 nm;

[0102] (5) depositing a silicon nitride layer on the aluminum-doped zinc oxide layer by PECVD, with a thickness of 60 nm;

[0103] (6) depositing a P-type microcrystalline silicon layer on the second tunneling silicon oxide layer by PECVD, with a thickness of 10 nm;

[0104] (7) depositing an indium tin oxide layer on the P-type microcrystalline silicon layer by PVD or RPD, with a thickness of 100 nm;

[0105] (8) using laser etching of the silicon nitride layer in the metal contact area to expose the aluminum-doped zinc oxide layer;

[0106] (9) forming a metal electrode by screen printing, wherein the front metal electrode contacts the aluminum-doped zinc oxide layer, the back metal electrode contacts the indium tin oxide layer, and the material of the metal electrode is silver or silver-clad copper;

[0107] (10) Use light injection to drive the redistribution of hydrogen ions in each layer and passivate matrix defects.

[0108] Example 3

[0109] A method for preparing a hybrid heterojunction solar cell comprises the following steps:

[0110] (1) Clean and polish the N-type silicon substrate, and texture the light-receiving surface to form a pyramid morphology on the front side;

[0111] (2) At 900°C, phosphorus is doped on the light-receiving surface of the silicon substrate to form a phosphorus diffusion layer with a thickness of 350 nm;

[0112] (3) depositing a tunneling silicon oxide layer (including a first tunneling silicon oxide layer and a second tunneling silicon oxide layer) on the light-receiving surface and the backlight surface of the silicon substrate by thermal oxidation, wherein the thickness of the tunneling silicon oxide layer is 2 nm;

[0113] (4) depositing an aluminum-doped zinc oxide layer on the first tunneling silicon oxide layer by ALD, the thickness of which is 40 nm;

[0114] (5) depositing a silicon nitride layer on the aluminum-doped zinc oxide layer by PECVD, with a thickness of 30 nm;

[0115] (6) depositing a P-type microcrystalline silicon layer on the second tunneling silicon oxide layer by PECVD, with a thickness of 50 nm;

[0116] (7) depositing an indium tin oxide layer on the P-type microcrystalline silicon layer by PVD or RPD, with a thickness of 120 nm;

[0117] (8) using laser etching of the silicon nitride layer in the metal contact area to expose the aluminum-doped zinc oxide layer;

[0118] (9) forming a metal electrode by screen printing, wherein the front metal electrode contacts the aluminum-doped zinc oxide layer, the back metal electrode contacts the indium tin oxide layer, and the material of the metal electrode is silver or silver-clad copper;

[0119] (10) Use light injection to drive the redistribution of hydrogen ions in each layer and passivate matrix defects.

[0120] Example 4

[0121] A method for preparing a hybrid heterojunction solar cell comprises the following steps:

[0122] (1) Clean and polish the N-type silicon substrate, and texture the light-receiving surface to form a pyramid morphology on the front side;

[0123] (2) At 900°C, phosphorus is doped on the light-receiving surface of the silicon substrate to form a phosphorus diffusion layer with a thickness of 500 nm;

[0124] (3) depositing a tunneling silicon oxide layer (including a first tunneling silicon oxide layer and a second tunneling silicon oxide layer) on the light-receiving surface and the backlight surface of the silicon substrate by thermal oxidation, wherein the thickness of the tunneling silicon oxide layer is 0.5 nm;

[0125] (4) depositing an aluminum-doped zinc oxide layer on the first tunneling silicon oxide layer by ALD, wherein the thickness of the layer is 10 nm;

[0126] (5) depositing a silicon nitride layer on the aluminum-doped zinc oxide layer by PECVD, with a thickness of 50 nm;

[0127] (6) depositing a P-type microcrystalline silicon layer on the second tunneling silicon oxide layer by PECVD, with a thickness of 20 nm;

[0128] (7) depositing an indium tin oxide layer on the P-type microcrystalline silicon layer by PVD or RPD, with a thickness of 70 nm;

[0129] (8) using laser etching of the silicon nitride layer in the metal contact area to expose the aluminum-doped zinc oxide layer;

[0130] (9) forming a metal electrode by screen printing, wherein the front metal electrode contacts the aluminum-doped zinc oxide layer, the back metal electrode contacts the indium tin oxide layer, and the material of the metal electrode is silver or silver-clad copper;

[0131] (10) Use light injection to drive the redistribution of hydrogen ions in each layer and passivate matrix defects.

[0132] Comparative Example 1

[0133] A method for preparing a hybrid heterojunction solar cell comprises the following steps:

[0134] (1) Clean and polish the N-type silicon substrate, and texture the light-receiving surface to form a pyramid morphology on the front side;

[0135] (2) depositing a tunneling silicon oxide layer (including a first tunneling silicon oxide layer and a second tunneling silicon oxide layer) on the light-receiving surface and the backlight surface of the silicon substrate by thermal oxidation, wherein the thickness of the tunneling silicon oxide layer is 1.4 nm;

[0136] (3) depositing an N-type microcrystalline silicon layer on the first tunneling silicon oxide layer by CVD, the thickness of which is 30 nm;

[0137] (4) depositing an indium tin oxide layer on the N-type microcrystalline silicon layer by PVD, the thickness of which is 80 nm;

[0138] (5) depositing a P-type microcrystalline silicon layer on the second tunneling silicon oxide layer by CVD, the thickness of which is 30 nm;

[0139] (6) depositing an indium tin oxide layer on the P-type microcrystalline silicon layer by PVD, the thickness of which is 80 nm;

[0140] (7) forming a metal electrode by screen printing, wherein the front metal electrode contacts the indium tin oxide layer on the light-receiving side, and the back metal electrode contacts the indium tin oxide layer on the backlight side, and the material of the metal electrode is silver or silver-clad copper;

[0141] (8) Use light injection to drive the redistribution of hydrogen ions in each layer and passivate matrix defects.

[0142] Comparative Example 2

[0143] A method for preparing a standard heterojunction solar cell comprises the following steps:

[0144] (1) Clean and polish the N-type silicon substrate, and texture the light-receiving surface to form a pyramid morphology on the front side;

[0145] (2) depositing an intrinsic amorphous silicon layer (including a first tunneling layer and a second tunneling layer) on the light-receiving surface and the backlight surface of the silicon substrate by thermal oxidation, with a thickness of 4 nm;

[0146] (3) depositing an N-type microcrystalline silicon layer on the first tunneling layer by CVD, the thickness of which is 8 nm;

[0147] (4) depositing an indium tin oxide layer on the N-type microcrystalline silicon layer by PVD, the thickness of which is 80 nm;

[0148] (5) depositing a P-type microcrystalline silicon layer on the second tunneling layer by CVD, with a thickness of 8 nm;

[0149] (6) depositing an indium tin oxide layer on the P-type microcrystalline silicon layer by PVD, the thickness of which is 80 nm;

[0150] (7) forming a metal electrode by screen printing, wherein the front metal electrode contacts the indium tin oxide layer on the light-receiving side, and the back metal electrode contacts the indium tin oxide layer on the backlight side, and the material of the metal electrode is silver or silver-clad copper;

[0151] (8) Use light injection to drive the redistribution of hydrogen ions in each layer and passivate matrix defects.

[0152] UV attenuation test

[0153] The heterojunction solar cells prepared in Examples 1-4 and Comparative Examples 1-2 were used for UV attenuation testing, specifically, the test cells were placed on a 60°C heating table, and exposed to ultraviolet light with an irradiation band of at least UVB (280-320nm) and UVC (100-280nm), and the efficiency attenuation before and after continuous 60kw·h irradiation was compared. The results are shown in Table 1.

[0154] Table 1

[0155]

[0156]

[0157] The results show that the power attenuation of the heterojunction solar cell prepared in the embodiment is significantly lower than that of the comparative example after the 60kw·h UV attenuation test. The heterojunction solar cell prepared in the embodiment has a lower attenuation because the light-receiving surface structure is completely resistant to ultraviolet radiation, and the ultraviolet light is limited by the wavelength requirements and will not irradiate the back of the battery, and the microcrystalline structure on the back has no ultraviolet attenuation problem. The reason why the attenuation effect in comparative examples 1-2 is reduced is the lack of a phosphorus diffusion layer as a front surface field passivation layer, and comparative example 2 also includes a microcrystalline silicon / amorphous silicon structure, which is prone to ultraviolet induced attenuation when exposed to ultraviolet radiation. In summary, the hybrid heterojunction solar cell structure provided by the present invention has stronger ultraviolet radiation resistance, and the double-sided intrinsic amorphous silicon and the front and back doped amorphous silicon in the traditional heterojunction are all grown by a single PECVD device, which has high cost. The present invention can reduce the use of PECVD equipment, and the equipment complexity and price are greatly reduced, which is more suitable for mass production.

[0158] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0159] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A hybrid heterojunction solar cell, characterized in that: include: A semiconductor substrate, wherein the semiconductor substrate has a light-receiving surface and a light-receiving surface opposite to each other; A phosphorus diffusion layer is disposed on the light receiving surface of the semiconductor substrate; A first tunneling oxide layer is disposed on a surface of the phosphorus diffusion layer away from the semiconductor substrate; An electron transport layer is disposed on a surface of the first tunneling oxide layer away from the semiconductor substrate; The anti-reflection layer is disposed on the surface of the electron transport layer away from the semiconductor substrate.

2. The hybrid heterojunction solar cell according to claim 1, characterized in that: The thickness of the phosphorus diffusion layer is 50nm-500nm.

3. The hybrid heterojunction solar cell according to claim 1, characterized in that: The material of the first tunneling oxide layer includes silicon oxide.

4. The hybrid heterojunction solar cell according to claim 1, characterized in that: The thickness of the first tunnel oxide layer is 0.5 nm-2 nm.

5. The hybrid heterojunction solar cell according to claim 1, characterized in that: The material of the electron transport layer includes at least one of aluminum-doped zinc oxide, gallium-doped zinc oxide, aluminum-gallium co-doped zinc oxide or zinc oxide.

6. The hybrid heterojunction solar cell according to claim 1, characterized in that: The thickness of the electron transport layer is 10nm-40nm.

7. The hybrid heterojunction solar cell according to claim 1, characterized in that: The material of the anti-reflection layer includes silicon nitride and / or silicon oxynitride.

8. The hybrid heterojunction solar cell according to claim 1, characterized in that: The thickness of the anti-reflection layer is 30nm-60nm.

9. The hybrid heterojunction solar cell according to any one of claims 1 to 8, characterized in that: Also includes: A second tunneling oxide layer is disposed on the backlight surface of the semiconductor substrate; A doped semiconductor layer is disposed on a surface of the second tunneling oxide layer away from the semiconductor substrate; The conductive layer is disposed on a surface of the doped semiconductor layer away from the semiconductor substrate.

10. The hybrid heterojunction solar cell according to claim 9, characterized in that: The hybrid heterojunction solar cell also satisfies at least one of the following conditions: The material of the second tunneling oxide layer includes silicon oxide; The thickness of the second tunneling oxide layer is 0.5nm-2nm; The material of the doped semiconductor layer includes boron-doped amorphous silicon and / or boron-doped microcrystalline silicon; The thickness of the doped semiconductor layer is 10nm-50nm; The material of the conductive layer includes at least one of indium oxide, tin oxide and zinc oxide; The thickness of the conductive layer is 70nm-120nm.

11. A method for preparing a hybrid heterojunction solar cell according to any one of claims 1 to 10, characterized in that: include: Providing a semiconductor substrate, wherein the semiconductor substrate has a light-receiving surface and a light-receiving surface opposite to each other; A phosphorus diffusion layer, a first tunneling oxide layer, an electron transport layer and an anti-reflection layer are sequentially formed on the light-receiving surface of the semiconductor substrate.

12. The preparation method according to claim 11, characterized in that: Also includes: A second tunneling oxide layer, a doped semiconductor layer and a conductive layer are sequentially formed on the backlight surface of the semiconductor substrate.

13. A battery assembly, characterized in that: A hybrid heterojunction solar cell comprising the hybrid heterojunction solar cell according to any one of claims 1 to 10, or a hybrid heterojunction solar cell prepared according to the preparation method according to claim 11 or 12.

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