Solar cell and photovoltaic module
By forming a crystal state locally in the dielectric layer of the solar cell, the problems of poor structural stability and anti-reverse effect of the dielectric layer are solved, and the effect of improving the reliability of the solar cell and the utilization rate of light is achieved.
Patent Information
- Application Number
- CN202510075656.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-16
- Publication Date
- 2025-05-30
AI Technical Summary
The dielectric layer structure of solar cells is poor, which affects the reliability and service life of the product. At the same time, the reverse reduction effect is poor, reducing the light absorption utilization rate.
By locally forming crystalline states in the dielectric layer, the structural stability of the dielectric layer is enhanced and its reaction-reaction is improved, thereby improving the reliability of solar cells and the utilization rate of light absorption.
The locally crystalline dielectric layer improves the structural stability and anti-reverse effect of solar cells, extends the service life and improves the light absorption efficiency.
Smart Images
Figure CN120076487A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of photovoltaic technology, and particularly to a solar cell and a photovoltaic module. Background Art
[0002] At present, as a new energy alternative, solar cells are used more and more widely. Among them, a photovoltaic solar cell is a device that converts the light energy of the sun into electrical energy. Specifically, a solar cell uses the photovoltaic effect principle to generate carriers, and then uses electrodes to lead out the carriers, so as to effectively utilize electrical energy.
[0003] However, in the actual use process, the general structure of the dielectric layer of a solar cell is relatively poor in stability, which affects the reliability and service life of the product. In addition, the antireflection effect of the dielectric layer is relatively poor, reducing the light absorption utilization rate of the solar cell. Summary of the Invention
[0004] The purpose of this application is to provide a solar cell and a photovoltaic module, so as to improve the antireflection effect of the dielectric layer of the solar cell, while improving the reliability of the solar cell and extending its service life.
[0005] To achieve the above purpose, this application provides the following technical solutions:
[0006] A solar cell, the solar cell includes a semiconductor substrate and a dielectric layer provided on the semiconductor substrate, the dielectric layer includes an amorphous state, and at least a part of the dielectric layer forms a crystalline state.
[0007] Adopting this technical solution, the local appearance of a crystalline state in the dielectric layer can enhance the structural stability of the dielectric layer, thereby improving the reliability of the solar cell and extending its service life. In addition, the local appearance of a crystalline state in the dielectric layer can also improve the antireflection effect of the dielectric layer, and further improve the light absorption utilization rate of the solar cell. In addition, when the dielectric layer covering the first action area (the area directly irradiated by the laser and / or the area affected by laser heat) is used as the connection layer between the electrode and the doped semiconductor layer, the dielectric layer covering the first action area forms a crystalline state, so that the conductivity of the dielectric layer covering the first action area is improved, which is beneficial to reducing the contact resistance between the surface of the dielectric layer and the electrode and reducing current loss.
[0008] In one implementation, the dielectric layer includes one or more laminated layers of a silicon nitride layer, a silicon oxynitride layer, and a silicon oxide layer.
[0009] In one implementation, the crystalline state includes one or more of crystalline silicon, crystalline silicon nitride, and crystalline silicon oxynitride;
[0010] In one implementation, the semiconductor substrate includes a first functional region and a second functional region, and the crystalline state is located in the dielectric layer covering the first functional region.
[0011] In one implementation, the degree of crystallization of the dielectric layer covering the second functional region is less than that of the dielectric layer covering the first functional region.
[0012] In one implementation, the dielectric layer includes an opposite first dielectric layer surface and a second dielectric layer surface, and the first dielectric layer surface is farther from the semiconductor substrate than the second dielectric layer surface;
[0013] In the first functional region, the degree of crystallization of the first dielectric layer surface is greater than that of the second dielectric layer surface; and / or, the alkali resistance of the dielectric layer covering the first functional region is lower than that of the dielectric layer covering the second functional region; and / or, the acid resistance of the dielectric layer covering the first functional region is higher than that of the dielectric layer covering the second functional region.
[0014] In one implementation, the surface of the dielectric layer covering the first functional region includes an oxide layer.
[0015] In one implementation, the thickness of the oxide layer is 10% - 50% of the thickness of the dielectric layer;
[0016] and / or, the oxide layer includes silicon oxide.
[0017] In one implementation, the dielectric layer covering the first functional region includes holes.
[0018] In one implementation, the solar cell further includes: a first doped semiconductor layer and a first electrode;
[0019] Wherein, the semiconductor substrate has a first surface;
[0020] The entire layer or a part of the first doped semiconductor layer is disposed on the first surface, and the dielectric layer is located on the side of the first doped semiconductor layer away from the semiconductor substrate;
[0021] The dielectric layer covers the first functional region and the second functional region;
[0022] The dielectric layer covering the first functional region includes holes, and the holes are filled with a conductive material, and the first electrode is electrically connected to the first doped semiconductor layer through the conductive material.
[0023] In one implementation, the solar cell further includes: a second doped semiconductor layer and a second electrode;
[0024] Wherein, the first surface includes a first region, a second region arranged at intervals, and an isolation region located between the first region and the second region;
[0025] The first doped semiconductor layer is disposed in the first region, and the second doped semiconductor layer is disposed in the second region; the conduction types of the first doped semiconductor layer and the second doped semiconductor layer are opposite;
[0026] The dielectric layer is located on a side of the first doped semiconductor layer and the second doped semiconductor layer facing away from the semiconductor substrate;
[0027] The dielectric layer covering the first active region includes holes, and the holes are filled with a conductive material;
[0028] The second electrode is electrically connected to the second doped semiconductor layer through the conductive material.
[0029] In one implementation, the solar cell further includes: a third doped semiconductor layer and a fourth doped semiconductor layer;
[0030] Wherein, the semiconductor substrate has a first surface, and the first surface includes a first region, a second region arranged at intervals, and an overlapping region located between the first region and the second region;
[0031] The dielectric layer covers the first active region and the second active region; the second active region is located at the edge of the first active region;
[0032] The third doped semiconductor layer is disposed in the first region and the overlapping region; the fourth doped semiconductor layer is disposed in the second region and at least part of the overlapping region;
[0033] The conduction types of the third doped semiconductor layer and the fourth doped semiconductor layer are opposite;
[0034] In the overlapping region, the dielectric layer is disposed on the third doped semiconductor layer and is farther away from the semiconductor substrate than the third doped semiconductor layer.
[0035] In one implementation, the solar cell further includes: a first doped semiconductor layer and an electrode;
[0036] Wherein, the semiconductor substrate has a first surface;
[0037] The first doped semiconductor layer is entirely or partially disposed on the first surface, and the dielectric layer is located on a side of the first doped semiconductor layer facing away from the semiconductor substrate;
[0038] The dielectric layer covers the first active region and the second active region; the first active region is located at the edge of the second active region;
[0039] The electrode is electrically connected to the first doped semiconductor layer.
[0040] A photovoltaic module includes the solar cell as described in any one of the above.
[0041] Compared with the prior art, the beneficial effects of the photovoltaic module provided by the embodiments of the present application are the same as those of the above solar cell, and will not be elaborated herein. Description of the Drawings
[0042] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The schematic embodiments and descriptions thereof of the present application are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:
[0043] Figure 1 It is a schematic diagram of a dielectric layer provided by an embodiment of the present application;
[0044] Figure 2 It is a cross-sectional view of the solar cell provided by an embodiment of the present application;
[0045] Figure 3 It is a cross-sectional view of the solar cell provided by another embodiment of the present application;
[0046] Figure 4 It is a cross-sectional view of the solar cell provided by another embodiment of the present application;
[0047] Figure 5 It is a schematic diagram of a dielectric layer provided by another embodiment of the present application;
[0048] Figure 6 It is a distribution diagram of oxygen elements from the surface to the inside of the dielectric layer provided by an embodiment of the present application.
[0049] Reference Signs:
[0050] 1 - semiconductor substrate, 1a - laser irradiation area, 1b - non - laser action area, 1c - laser influence area, 2 - dielectric layer, 2a - hole. Detailed Embodiments
[0051] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.
[0052] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.
[0053] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality of" means two or more unless otherwise specifically defined. "Several" means one or more unless otherwise specifically defined.
[0054] In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of this application.
[0055] In the description of this application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0056] Please refer to Figure 1 , the solar cell provided by the embodiment of this application includes a semiconductor substrate 1 and a dielectric layer 2 disposed on the semiconductor substrate 1, and the dielectric layer 2 has a passivation effect. As Figure 1As shown, the dielectric layer 2 includes an amorphous state, and the dielectric layer 2 is at least partially formed into a crystalline state. Specifically, the dielectric layer 2 itself is in an amorphous state, and its local part is processed to form a crystalline state; for example, the local part of the dielectric layer 2 forms a crystalline state after being irradiated with a laser. With this technical solution, a crystalline state appears locally in the dielectric layer 2, which can enhance the structural stability of the dielectric layer 2, thereby improving the reliability of the solar cell and extending its service life. In addition, the appearance of a crystalline state locally in the dielectric layer 2 can also improve the antireflection effect of the dielectric layer 2, and further improve the light absorption utilization rate of the solar cell. In addition, when the dielectric layer 2 covering the first action area (the area directly irradiated by the laser and / or the area affected by laser heat) is used as the connection layer between the electrode and the doped semiconductor layer, the dielectric layer 2 covering the first action area forms a crystalline state, which improves the conductivity of the dielectric layer 2 covering the first action area, is conducive to reducing the contact resistance between the surface of the dielectric layer 2 and the electrode, and reducing current loss.
[0057] In some embodiments, the dielectric layer 2 includes one or more stacked layers of a silicon nitride layer, a silicon oxynitride layer, and a silicon oxide layer. Specifically, when the dielectric layer 2 has a single-layer structure, the dielectric layer 2 can be a silicon nitride layer, a silicon oxynitride layer, or a silicon oxide layer. When the dielectric layer 2 has a double-layer structure, the dielectric layer 2 can include a stacked silicon nitride layer and a silicon oxynitride layer, or can include a stacked silicon nitride layer and a silicon oxide layer. Of course, it can also include a stacked silicon oxynitride layer and a silicon oxide layer, and the stacking order of each layer can be set according to the actual situation. When the dielectric layer 2 has a three-layer structure, the dielectric layer 2 can include a stacked silicon nitride layer, a silicon oxynitride layer, and a silicon oxide layer, and the stacking order of the silicon nitride layer, the silicon oxynitride layer, and the silicon oxide layer can be set according to the actual situation. The dielectric layer 2 made of the above various materials has a low cost, has a passivation effect, good adhesiveness, and is easy to manufacture.
[0058] In some embodiments, the crystalline state includes one or more of crystalline silicon, crystalline silicon nitride, and crystalline silicon oxynitride. Specifically, the crystalline state locally formed in the dielectric layer 2 can only include crystalline silicon, or can only include crystalline silicon nitride, or can only include crystalline silicon oxynitride. Or, the crystalline state locally formed in the dielectric layer 2 can include any two of crystalline silicon, crystalline silicon nitride, and crystalline silicon oxynitride; or, the crystalline state includes crystalline silicon, crystalline silicon nitride, and crystalline silicon oxynitride. Among them, the size of the crystalline silicon, crystalline silicon nitride, and / or crystalline silicon oxynitride is 0.01 nm - 100 nm. For example, the size of the crystalline silicon, crystalline silicon nitride, and / or crystalline silicon oxynitride is 0.01 nm, 1 nm, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, or 100 nm, etc. That is, the above crystalline silicon is nanocrystalline silicon.
[0059] Further, the above crystalline silicon may also be microcrystalline silicon.
[0060] In some embodiments, the first action area includes a laser irradiation area 1a (the area of the dielectric layer 2 irradiated by the laser) and a laser influence area 1c (the area of the dielectric layer 2 affected by the laser heat), and the second action area includes a non-laser action area (the area not affected by the laser at all). In this technical solution, the dielectric layer 2 covers the first action area and the second action area, that is, the dielectric layer 2 covers the laser irradiation area 1a, the laser influence area 1c, and the non-laser action area 1b. Among them, the number of the first action areas is multiple and the multiple first action areas are independent of each other and do not connect. In this way, the dielectric layer 2 covering the first action area (the laser irradiation area 1a and the laser influence area 1c) can be used as a connection layer between the electrode and the doped semiconductor layer, and the dielectric layer 2 covering the first action area forms a crystalline state, so that the conductivity of the dielectric layer 2 covering the first action area is improved, which is beneficial to reducing the contact resistance between the surface of the dielectric layer 2 and the electrode and reducing current loss.
[0061] Alternatively, the first action area includes a laser irradiation area 1a (the area of the dielectric layer 2 irradiated by the laser), and the second action area includes a laser influence area 1c (the area of the dielectric layer 2 affected by the laser heat) and a non-laser action area (the area not affected by the laser at all).
[0062] As Figure 3 shown, the laser influence area 1c is arranged around the edge of the laser irradiation area 1a and the laser influence area 1c is located between the laser irradiation area 1a and the non-laser action area 1b (the area not affected by the laser at all). Among them, the part of the dielectric layer 2 corresponding to the laser irradiation area 1a is the directly laser-irradiated area, and the part of the dielectric layer 2 corresponding to the laser irradiation area 1a forms a crystalline state after being irradiated by the laser. Although the laser influence area 1c is not directly irradiated by the laser, it will also form a crystalline state under the influence of the laser heat effect.
[0063] In some embodiments, since the dielectric layer 2 covering the laser influence area 1c is not directly irradiated by the laser but only affected by the laser heat radiation effect, the crystallization degree of the dielectric layer 2 covering the laser influence area 1c is less than that of the dielectric layer 2 covering the laser irradiation area 1a, that is, the crystallization degree of the dielectric layer 2 covering the laser influence area 1c is relatively low. Adopting this technical solution, from the part of the dielectric layer 2 covering the laser irradiation area 1a to the part of the dielectric layer 2 covering the non-laser action area 1b, its crystallization degree forms an intermediate transition in the part of the dielectric layer 2 covering the laser influence area 1c, avoiding too large a change in the crystallization degree in the adjacent area and affecting the performance of the entire dielectric layer 2.
[0064] In some embodiments, the first action area includes a laser affected area 1c, and the second action area includes a non-laser action area 1b (an area that is not affected by the laser at all). The area of the dielectric layer 2 corresponding to the laser irradiation area 1a is removed to form a hollow hole. In this technical solution, the dielectric layer 2 covers the laser affected area 1c and the non-laser action area 1b. Specifically, during the process of using an etching solution to remove the dielectric layer 2 covering the laser irradiation area 1a and retaining the dielectric layer 2 covering the non-laser action area 1b and the laser affected area 1c, patterning of the dielectric layer 2 is achieved, and a hollow hole is formed in the area of the dielectric layer 2 corresponding to the laser irradiation area 1a. By adopting this technical solution, the dielectric layer 2 can play a masking effect, and other functional layers can be formed in the area of the hollow hole.
[0065] In some embodiments, the first action area includes a laser irradiation area 1a, the second action area includes a laser affected area 1c, and the second action area is located at the edge of the first action area, that is, the laser affected area 1c is located at the edge of the laser irradiation area 1a. In this technical solution, the dielectric layer 2 covers the first action area and the second action area, that is, the dielectric layer 2 covers the laser irradiation area 1a and the laser affected area 1c. The area of the dielectric layer 2 corresponding to the non-laser action area is removed to form a hollow hole. Specifically, during the process of using an etching solution to remove the dielectric layer 2 covering the non-laser action area 1b and retaining the dielectric layer 2 covering the laser irradiation area 1a and the laser affected area 1c, a hollow hole is formed in the area of the dielectric layer 2 corresponding to the non-laser action area 1b. By adopting this technical solution, the retained dielectric layer 2 of the laser irradiation area 1a and the laser affected area 1c can be used as an isolation material between doped semiconductor layers with opposite conduction types to prevent leakage between doped semiconductor layers with opposite conduction types.
[0066] In some other embodiments, along the thickness direction of the dielectric layer 2, the two opposite surfaces on both sides of the dielectric layer 2 are respectively the first surface and the second surface of the dielectric layer. A part of the first surface is irradiated by the laser, and the entire second surface is not irradiated by the laser. In the first action area, along the direction from the first surface to the second surface, the crystallization degree of the dielectric layer 2 gradually decreases. In addition, in the first action area, the crystallization degree of the first surface is greater than that of the second surface. With such a setting, the part of the dielectric layer 2 covering the first action area has a higher crystallization degree on the surface, which further makes the antireflection effect of the dielectric layer 2 near the surface better and the reliability better. In addition, when the dielectric layer 2 covering the first action area is used as a connection layer between an electrode and a doped semiconductor layer, the crystallinity of the surface of the dielectric layer 2 covering the first action area is relatively high, making the conductivity of the dielectric layer 2 near the surface better, which is beneficial to reducing the contact resistance between the surface of the dielectric layer 2 and the electrode and reducing current loss.
[0067] In some embodiments, under the action of laser irradiation or laser thermal influence, the alkali resistance of the dielectric layer 2 covering the first action area is reduced, resulting in the alkali resistance of the dielectric layer 2 covering the first action area being lower than that of the dielectric layer 2 covering the second action area. With this technical solution, as Figure 2 shown, part of the dielectric layer can be removed by etching with an alkali solution, and then the dielectric layer 2 corresponding to the laser irradiation area 1a can be removed, while the dielectric layer 2 covering the non-laser action area 1b is retained, thereby realizing patterning of the dielectric layer 2 so that the dielectric layer 2 can function as a mask.
[0068] It can be understood that the alkali resistance of the dielectric layer 2 covering the laser irradiation area 1a is lower than that of the dielectric layer 2 covering the laser influence area 1c, and the dielectric layer 2 covering the laser influence area 1c can be selectively etched away or retained by controlling the concentration of the alkali solution.
[0069] In other embodiments, under the action of laser irradiation or laser thermal influence, the acid resistance of the dielectric layer 2 covering the first action area is increased, resulting in the acid resistance of the dielectric layer 2 covering the first action area being higher than that of the dielectric layer 2 covering the second action area. With this technical solution, as Figure 4 shown, part of the dielectric layer can be removed by etching with an acid solution, and then the dielectric layer 2 covering the non-laser action area 1b can be removed, while the dielectric layer 2 covering the laser irradiation area 1a and the laser influence area 1c is retained, thereby realizing patterning of the dielectric layer 2.
[0070] It can be understood that the acid resistance of the dielectric layer 2 covering the laser irradiation area 1a is higher than that of the dielectric layer 2 covering the laser influence area 1c, and the dielectric layer 2 covering the laser influence area 1c can be selectively etched away or retained by controlling the concentration of the acid solution.
[0071] In other embodiments, during the process of laser irradiation or laser thermal influence, the surface of the first action area is in contact with oxygen, resulting in the formation of an oxide layer on the surface of the dielectric layer 2 covering the first action area, that is, the surface of the dielectric layer 2 covering the first action area includes an oxide layer, and this oxide layer can be crystalline, non-crystalline, or part of the oxides in the oxide layer are crystalline and the other part is non-crystalline. Among them, the properties of the oxides are more stable. The formation of an oxide layer on the surface of the dielectric layer 2 in the first action area can further improve the stability of the dielectric layer 2 and further improve the reliability of this solar cell.
[0072] In some embodiments, if the thickness of the oxide layer is too thick, the manufacturing difficulty is relatively high; if the thickness of the oxide layer is too thin, the stability of the dielectric layer 2 is affected. Therefore, in this technical solution, the thickness of the oxide layer is 10% to 50% of the thickness of the dielectric layer 2. In this way, while ensuring the stability of the dielectric layer 2, the processing difficulty of the oxide layer is reduced. Exemplarily, the thickness of the oxide layer is 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35%, 38%, 40%, 42%, 45%, 48% or 50% of the thickness of the dielectric layer 2, etc.
[0073] In addition, the oxide layer includes silicon oxide. Specifically, the silicon atoms on the surface of the dielectric layer 2 covering the first active region come into contact with oxygen and react to form silicon oxide.
[0074] In some embodiments, the laser irradiation region 1a on the first surface of the dielectric layer 2 is irradiated by a laser, and the entire second surface of the dielectric layer 2 is not irradiated by the laser. In this technical solution, in the first active region, the oxygen content on the first surface of the dielectric layer 2 is greater than that on the second surface, that is, in the dielectric layer covering the first active region, the oxygen content on the irradiated surface is greater than that on the non-irradiated surface. Alternatively, along the thickness direction of the dielectric layer 2, and from the first surface to the second surface of the dielectric layer 2, the oxygen content in the dielectric layer 2 covering the first active region gradually decreases. As Figure 6 shown, Figure 6 in the figure, the abscissa is the binding energy, and the ordinate is the change in the oxygen content per second (counts per second), where the curve from 0 to 5 represents the oxygen content when the depth gradually increases along the direction from the first surface to the second surface. With such a setting, the oxygen content on the surface of the dielectric layer 2 covering the first active region is the largest and the performance is the most stable, which can further improve the stability of the dielectric layer 2.
[0075] In some embodiments, as Figure 5 shown, the dielectric layer 2 covering the first active region includes holes 2a. By adopting this technical solution, the dielectric layer 2 in the first active region does not need to be completely removed. There are holes 2a inside. Through the conductive material in the holes 2a, electrical contact between the electrode and the doped semiconductor layer on the side of the dielectric layer 2 close to the semiconductor substrate can be achieved, especially for electrodes made by methods such as electroplating, electroless plating, and physical vapor deposition. The pulling force of the electrode on the solar cell can be greatly improved and it is not easy to fall off.
[0076] In some embodiments, in the dielectric layer 2 covering the first active region, the holes 2a formed on the first surface are smaller than the holes 2a formed on the second surface, that is, the holes 2a formed on the surface irradiated by the laser are smaller than the holes 2a formed on the surface not irradiated by the laser. In addition, in the dielectric layer 2 covering the first active region, the number of the holes 2a formed on the first surface is smaller than the number of the holes 2a formed on the second surface, that is, the number of the holes 2a formed on the surface irradiated by the laser is smaller than the number of the holes 2a formed on the surface not irradiated by the laser. With such a setting, it is ensured that the surface density of the dielectric layer 2 covering the first active region is higher, and the stability of the performance of the dielectric layer 2 is further improved.
[0077] In some embodiments, the first active region includes a first sub-active region and a second sub-active region. The dielectric layer 2 covers the first sub-active region and the second sub-active region. The size of the holes in the dielectric layer covering the first sub-active region is smaller than the size of the holes in the dielectric layer covering the second sub-active region; and / or, the number of the holes in the dielectric layer covering the first sub-active region is smaller than the number of the holes in the dielectric layer covering the second sub-active region. This makes the density of the dielectric layer 2 covering the first sub-active region higher. When the dielectric layer 2 covering the first active region is used as a connection layer between the electrode and the doped semiconductor layer, it is beneficial to improve the adhesion between the doped semiconductor layer and the electrode and enhance the pulling force.
[0078] In some embodiments, the solar cell further includes a first doped semiconductor layer and an electrode. Among them, the semiconductor substrate 1 has a first surface. The first doped semiconductor layer can be disposed entirely on the first surface or partially on the first surface. The dielectric layer 2 is located on the side of the first doped semiconductor layer away from the semiconductor substrate 1. In this embodiment, as Figure 2 shown, the dielectric layer 2 covers the first active region and the second active region. The first active region is located at the edge of the second active region. The first active region includes a laser affected region 1c, and the second active region includes a non-laser action region 1b, that is, the laser affected region 1c is located at the edge of the non-laser action region 1b. That is, the dielectric layer 2 covers the laser affected region 1c and the non-laser action region 1b, the dielectric layer 2 does not cover the laser irradiation region 1a, and a hollow is formed in the part of the dielectric layer 2 corresponding to the laser irradiation region 1a. The electrode is electrically connected to the first doped semiconductor layer in the region corresponding to the laser irradiation region 1a.
[0079] In some embodiments, the dielectric layer 2 is a silicon nitride layer. There is also an alumina layer between the dielectric layer 2 and the first doped semiconductor layer. At the hollow formed in the part of the dielectric layer 2 corresponding to the laser irradiation region 1a, the edge of the alumina layer shrinks inward away from the hollow. In this technical solution, the first doped semiconductor layer can be a doped polysilicon layer.
[0080] In some embodiments, the solar cell further includes a first doped semiconductor layer and a first electrode. The semiconductor substrate 1 has a first surface. The first doped semiconductor layer may be disposed entirely on the first surface or partially on the first surface. The dielectric layer 2 is located on the side of the first doped semiconductor layer away from the semiconductor substrate 1. In this embodiment, the dielectric layer 2 covering the first active region includes holes 2a, and the holes 2a are filled with a conductive material. The solar cell further includes a first electrode, and the first electrode is electrically connected to the first doped semiconductor layer through the conductive material. The dielectric layer 2 covers the first active region and the second active region; the first active region includes a laser irradiation region 1a and a laser influence region 1c; the second active region includes a non-laser action region 1b. With such a setting, the electrical contact between the first electrode and the first doped semiconductor layer can be achieved through the conductive material in the holes 2a. Especially for electrodes fabricated by methods such as electroplating, electroless plating, and physical vapor deposition, the pulling force of the first electrode on the solar cell can be greatly improved, and it is not easy to fall off. The conductive material can be a conductive metal or a conductive adhesive, etc. In this embodiment, the solar cell can be a back-contact cell or a bifacial cell.
[0081] In some embodiments, the solar cell further includes a second doped semiconductor layer and a second electrode. The first surface includes a first region, a second region arranged at intervals, and an isolation region located between the first region and the second region. The first doped semiconductor layer is disposed in the first region, and the second doped semiconductor layer is disposed in the second region. The first doped semiconductor layer and the second doped semiconductor layer have opposite conductivity types to respectively collect and conduct electrons and holes, which is beneficial to forming a current. The dielectric layer 2 is located on the side of the first doped semiconductor layer and the second doped semiconductor layer away from the semiconductor substrate. The dielectric layer 2 covers the first active region and the second active region; the first active region includes a laser irradiation region 1a and a laser influence region 1c; the second active region includes a non-laser action region 1b. The dielectric layer 2 covering the first active region includes holes 2a, and the holes 2a are filled with a conductive material; the second electrode is electrically connected to the second doped semiconductor layer through the conductive material, so that the pulling force of the second electrode on the solar cell can be greatly improved, and it is not easy to fall off.
[0082] Exemplarily, in a solar cell, the first doped semiconductor layer is a doped polysilicon layer, which can be P-type doping or N-type doping, and can be specifically determined according to actual requirements. The second doped semiconductor layer can also be a doped polysilicon layer. When the first doped semiconductor layer is an N-type doped polysilicon layer, the second doped semiconductor is a P-type doped polysilicon layer. That is, their conductivity types are opposite.
[0083] In some embodiments, the solar cell further includes a first interface layer and a second interface layer. The first interface layer is located between the first doped semiconductor layer and the semiconductor substrate. When the first doped semiconductor layer is a doped polysilicon layer, the first interface layer can be a tunneling oxide layer. The second interface layer is located between the second doped semiconductor layer and the semiconductor substrate. When the second doped semiconductor layer is a doped polysilicon layer, the second interface layer can be a tunneling oxide layer. Thus, the passivation contact structure composed of the tunneling oxide layer and the doped polysilicon layer has excellent interface passivation effect, and can realize the selective collection of carriers, reduce the carrier recombination rate on the first surface of the semiconductor substrate, and further improve the photoelectric conversion efficiency of the solar cell. The material and thickness of the first interface layer can be set according to the material of the doped polysilicon layer and actual requirements, and no specific limitation is made here.
[0084] The material of the semiconductor substrate 1 can be selected from materials such as silicon (Si) or germanium (Ge), or materials such as gallium arsenide (GaAs). Obviously, in terms of the conduction type, the semiconductor substrate 1 can be an intrinsic conductive substrate, an n-type conductive substrate or a p-type conductive substrate. Optionally, the semiconductor substrate 1 is a p-type conductive substrate or an n-type conductive substrate. Compared with the intrinsic conductive substrate, the p-type conductive substrate or the n-type conductive substrate has better conductivity, so that the finally fabricated solar cell has lower bulk resistivity, thereby improving the efficiency of the solar cell.
[0085] Exemplarily, the semiconductor substrate 1 can be a p-type substrate or an n-type substrate. The n-type substrate has the advantages of high minority carrier lifetime, no light attenuation, and good low-light performance.
[0086] In some other embodiments, the solar cell further includes a semiconductor substrate 1, a third doped semiconductor layer, and a fourth doped semiconductor layer. The semiconductor substrate 1 has a first surface, and the first surface includes a first region, a second region, and an overlapping region. The first region and the second region are spaced apart on the first surface, and the overlapping region is located between the first region and the second region. The third doped semiconductor layer is formed on the first region and the overlapping region, and the fourth doped semiconductor layer is formed on the second region and at least part of the overlapping region. Moreover, the conductive types of the third doped semiconductor layer and the fourth doped semiconductor layer are opposite to each other to respectively collect and conduct out electrons and holes, which is conducive to forming a current. The dielectric layer 2 covers the first active region and the second active region; the first active region includes a laser irradiation region 1a, and the second active region includes a laser affected region 1c. In addition, in the overlapping region, the dielectric layer 2 is disposed between the third doped semiconductor layer and the fourth doped semiconductor layer and is farther from the semiconductor substrate 1 than the third doped semiconductor layer. That is, in the overlapping region, at least part of the dielectric layer 2 on the side of the third doped semiconductor layer away from the semiconductor substrate is retained. In this embodiment, the dielectric layer 2 is at least partially disposed on the first surface, and the regions of the dielectric layer 2 corresponding to the laser irradiation region 1a and the laser affected region 1c are retained, and a second hollow hole is formed in the region of the dielectric layer 2 corresponding to the non-laser active region 1b. With such an arrangement, the regions of the dielectric layer 2 corresponding to the laser irradiation region 1a and the laser affected region 1c are retained in the overlapping region to isolate the third doped semiconductor layer from the fourth doped semiconductor layer and prevent leakage.
[0087] Exemplarily, in a solar cell, the third doped semiconductor layer is a doped polysilicon layer, which can be P-type doped or N-type doped, and can be specifically determined according to actual requirements. The fourth doped semiconductor layer is a doped amorphous silicon layer and / or a doped microcrystalline silicon layer. When the third doped semiconductor layer is an N-type doped polysilicon layer, the fourth doped semiconductor layer is a P-type doped amorphous silicon layer and / or a P-type doped microcrystalline silicon layer. That is, the conductive types of the two are opposite to each other.
[0088] In some embodiments, the solar cell further includes a third interface layer and a fourth interface layer. The third interface layer is located between the third doped semiconductor layer and the semiconductor substrate. When the third doped semiconductor layer is a doped polysilicon layer, the third interface layer can be a tunneling oxide layer. The fourth interface layer is located between the fourth doped semiconductor layer and the semiconductor substrate. When the fourth doped semiconductor layer is a doped amorphous silicon layer and / or a doped microcrystalline silicon layer, the fourth interface layer can be an intrinsic amorphous silicon layer.
[0089] In addition, the embodiment of the present application further provides a photovoltaic module, which includes the solar cell provided in any of the above embodiments. A plurality of solar cells are electrically connected together in a series and / or parallel manner. Compared with the prior art, the beneficial effects of the photovoltaic module provided in the embodiment of the present application are the same as those of the above solar cell, and will not be elaborated herein.
[0090] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any one or more embodiments or examples in a suitable manner.
[0091] As described above, the specific embodiments of the present application are merely described, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claimed rights.
Claims
1. A solar cell, characterized in that: The solar cell comprises a semiconductor substrate and a dielectric layer arranged on the semiconductor substrate, wherein the dielectric layer comprises an amorphous state, and the dielectric layer at least partially forms a crystalline state.
2. The solar cell according to claim 1, characterized in that The dielectric layer includes one or more stacked layers of a silicon nitride layer, a silicon oxynitride layer and a silicon oxide layer.
3. The solar cell according to claim 2, characterized in that: The crystalline state includes one or more of crystalline silicon, crystalline silicon nitride, and crystalline silicon oxynitride.
4. The solar cell according to claim 1, characterized in that The semiconductor substrate includes a first active region and a second active region, and the crystalline state is located in a dielectric layer covering the first active region.
5. The solar cell according to claim 4, characterized in that: The crystallization degree of the dielectric layer covering the second active region is less than the crystallization degree of the dielectric layer covering the first active region.
6. The solar cell according to claim 4, characterized in that: The dielectric layer comprises a first dielectric layer surface and a second dielectric layer surface which are opposite to each other, and the first dielectric layer surface is away from the semiconductor substrate relative to the second dielectric layer surface; In the first active region, the crystallization degree of the first surface of the dielectric layer is greater than the crystallization degree of the second surface of the dielectric layer; And / or, the alkali resistance of the dielectric layer covering the first active area is lower than that of the dielectric layer covering the second active area; and / or, the acid resistance of the dielectric layer covering the first active area is higher than that of the dielectric layer covering the second active area.
7. The solar cell according to claim 4, characterized in that: The surface of the dielectric layer covering the first active region includes an oxide layer.
8. The solar cell according to claim 7, characterized in that: The thickness of the oxide layer is 10% to 50% of the thickness of the dielectric layer; And / or, the oxide layer includes silicon oxide.
9. The solar cell according to claim 4, characterized in that: The dielectric layer covering the first active region includes holes.
10. The solar cell according to claim 4, characterized in that: The solar cell further comprises: a first doped semiconductor layer and a first electrode; Wherein, the semiconductor substrate has a first surface; The first doped semiconductor layer is entirely or partially disposed on the first surface, and the dielectric layer is located on a side of the first doped semiconductor layer away from the semiconductor substrate; The dielectric layer covers the first active area and the second active area; The dielectric layer covering the first active area includes holes, the holes are filled with conductive material, and the first electrode is electrically connected to the first doped semiconductor layer through the conductive material.
11. The solar cell according to claim 10, characterized in that The solar cell further comprises: a second doped semiconductor layer and a second electrode; Wherein, the first surface includes a first area, a second area and an isolation area between the first area and the second area; The first doped semiconductor layer is disposed in the first region, and the second doped semiconductor layer is disposed in the second region; the first doped semiconductor layer and the second doped semiconductor layer have opposite conductivity types; The dielectric layer is located on a side of the first doped semiconductor layer and the second doped semiconductor layer away from the semiconductor substrate; The dielectric layer covering the first active area includes holes, and the holes are filled with conductive material; The second electrode is electrically connected to the second doped semiconductor layer through the conductive material.
12. The solar cell according to any one of claims 4 to 9, characterized in that: The solar cell further comprises: a third doped semiconductor layer and a fourth doped semiconductor layer; The semiconductor substrate has a first surface, and the first surface includes a first region, a second region and an overlapping region between the first region and the second region. The dielectric layer covers the first active area and the second active area; the second active area is located at the edge of the first active area; The third doped semiconductor layer is disposed in the first region and the overlapping region; the fourth doped semiconductor layer is disposed in the second region and at least a portion of the overlapping region; The conductivity type of the third doped semiconductor layer is opposite to that of the fourth doped semiconductor layer; In the overlapping region, the dielectric layer is disposed on the third doped semiconductor layer and is farther away from the semiconductor substrate than the third doped semiconductor layer.
13. The solar cell according to any one of claims 4 to 9, characterized in that: The solar cell further comprises: a first doped semiconductor layer and an electrode; Wherein, the semiconductor substrate has a first surface; The first doped semiconductor layer is entirely or partially disposed on the first surface, and the dielectric layer is located on a side of the first doped semiconductor layer away from the semiconductor substrate; The dielectric layer covers the first active area and the second active area; the first active area is located at the edge of the second active area; The electrode is electrically connected to the first doped semiconductor layer.
14. A photovoltaic module, characterized in that: The invention comprises the solar cell according to any one of claims 1 to 13.