Solar cell and its manufacturing method, electrical device

Abstract

A solar cell and its manufacturing method and application. The solar cell includes a substrate (100), an emitter layer (110), a first passivation layer (120), and a first anti-reflection layer (130) sequentially stacked on one side of the substrate (100), and a passivation contact structure (140) and a second anti-reflection layer (150) sequentially stacked on the other side of the substrate (100). The material of the first passivation layer (120) includes gallium oxide. The manufacturing method includes the steps of sequentially manufacturing the emitter layer (110), the first passivation layer (120), and the first anti-reflection layer (130) on one side of the substrate (100), and sequentially manufacturing the passivation contact structure (140) and the second anti-reflection layer (150) on the other side of the substrate (100). The solar cell is used as a power source.

Description

[Technical field]

[0001] Priority information This invention claims priority to Chinese application No. 202310376099.4, filed on April 10, 2023, entitled "Solar Cell and Its Manufacturing Method, Electrical Device," the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to the technical field of batteries, in particular to solar cells and their manufacturing methods, and electrical devices. [Background technology]

[0003] With the transformation of the global energy system towards low carbonization, the large-scale use of renewable energy and the clean low-carbonization of conventional energy have become the basic trend, and accelerating the development of renewable energy has become the mainstream direction of global energy transformation, of which photovoltaic power generation is a key field. A solar cell is mainly a large-area semiconductor photodiode, which is an electronic component that converts solar energy directly into electrical energy through the photovoltaic effect, and can convert light energy into electrical energy by absorbing light energy with photoelectric materials to produce a photoelectric effect. Therefore, solar energy power generation is also called photovoltaic power generation. The raw material for P-type batteries is P-type silicon wafers, and the raw material for N-type batteries is N-type silicon wafers. The main technological process of traditional monocrystalline and polycrystalline batteries of P-type batteries is aluminum backsurface field technology, and the currently mainstream P-type monocrystalline battery technology is PERC (Passivated Emitter and Rear Cell) technology. This technology has a simple manufacturing process and low cost. As P-type batteries gradually approach the limit of conversion efficiency, N-type batteries have become the development direction of next-generation battery technology. N-type batteries have advantages such as high conversion efficiency, high bifacial rate, low temperature coefficient, and long carrier life.

[0004] The manufacturing technology of N-type TOPCon high-efficiency solar cells is an important technology for solar cells, and is the key to improving the efficiency and reducing the cost of photovoltaic power generation. At present, the market demand for N-type TOPCon solar cells is large and is at its peak. TOPCon (Tunnel Oxide Passivating Contacts) cells use N-type silicon wafers, and first a layer of tunnel oxide of 1nm to 2nm is manufactured on the back of the cell, and then a layer of doped polysilicon is deposited, and the two form a passivation contact structure, providing excellent interface passivation to the back of the silicon wafer.

[0005] Traditionally, the manufacturing process of TOPCon high-efficiency solar cells requires that after the tunnel oxide passivation contact structure is formed, a dielectric passivation layer, usually an aluminum oxide layer, be deposited on the front side of the N-type silicon wafer to provide an effective field passivation effect. However, although aluminum oxide is water-insoluble, it has strong water absorption, strong adsorption power and catalytic activity, so that the intrusion of water vapor into TOPCon solar cells during practical use is likely to cause cell failure. Summary of the Invention [Problem to be solved by the invention]

[0006] According to various embodiments of the present invention, a solar cell, a manufacturing method thereof, and applications thereof are provided, and the solar cell can maintain high conversion efficiency while having excellent reliability even when placed in a high-temperature and high-humidity environment for a long period of time. [Means for solving the problem]

[0007] The present invention provides a solar cell, comprising a substrate, an emitter layer, a first passivation layer and a first anti-reflection layer sequentially stacked on one surface of the substrate, and a passivation contact structure and a second anti-reflection layer sequentially stacked on the other surface of the substrate, wherein the material of the first passivation layer includes gallium oxide.

[0008] In one embodiment, the solar cell further comprises a second passivation layer disposed between the passivation contact structure and the second anti-reflection layer, the material of the second passivation layer comprising gallium oxide.

[0009] In one embodiment, the passivation contact structure includes a tunnel oxide layer and a doped polysilicon layer stacked in sequence, the tunnel oxide layer facing one side of the substrate.

[0010] In one embodiment, the first anti-reflective layer and the second anti-reflective layer each independently include one or more of a silicon nitride layer, a silicon oxynitride layer, and a silicon oxide layer.

[0011] In one embodiment, the first anti-reflective layer comprises a first silicon nitride layer, the first silicon nitride layer being in contact with the first passivation layer.

[0012] In one embodiment, the solar cell further includes a first electrode and a second electrode, the first electrode penetrating the first passivation layer and the first anti-reflection layer to connect to the emitter layer, and the second electrode penetrating the second anti-reflection layer to connect to the passivation contact structure.

[0013] Furthermore, the present invention further provides a method for manufacturing the above-mentioned solar cell, comprising the steps of sequentially fabricating the emitter layer, the first passivation layer and the first anti-reflection layer on one side surface of the substrate, and sequentially fabricating the passivation contact structure and the second anti-reflection layer on the other side surface of the substrate.

[0014] In one embodiment, the first passivation layer is fabricated by one of atomic layer deposition, plasma enhanced chemical vapor deposition and physical vapor deposition.

[0015] In one embodiment, the conditions for manufacturing the first passivation layer and the second passivation layer by atomic layer deposition each independently include a reaction temperature of 210°C to 230°C and a reaction pressure of 20 torr to 35 torr in an atmosphere of 3000 sccm to 12000 sccm of trimethylgallium and 4000 sccm to 12000 sccm of ozone.

[0016] The present invention further provides an electrical device including the above-described solar cell as a power source.

[0017] The details of one or more embodiments of the invention are set forth in the drawings and description which follow. Other features, objects, and advantages of the invention will become apparent from the description, drawings, and claims. [Brief description of the drawings]

[0018] In order to more clearly explain the technical solutions of the embodiments of the present invention or the prior art, the drawings necessary for the description of the embodiments or the prior art will be briefly described below. The drawings in the following description are only the embodiments of the present invention, and it is obvious that those skilled in the art can obtain other drawings based on these drawings without creative work. [Figure 1] 1 is a structural schematic diagram of a solar cell according to an embodiment of the present invention. [Diagram 2] 1 is a structural schematic diagram of a solar cell according to an embodiment of the present invention. [Diagram 3] 1 is a structural schematic diagram of a solar cell according to an embodiment of the present invention. [Figure 4] 1 is a structural schematic diagram of a solar cell according to an embodiment of the present invention. [Diagram 5] 1 is a structural schematic diagram of a solar cell according to an embodiment of the present invention. [Figure 6] 1 is a structural schematic diagram of a solar cell according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The technical solutions of the embodiments of the present invention will be described clearly and completely below with reference to the drawings of the embodiments of the present invention. It is clear that the described embodiments are only some of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained based on the embodiments of the present invention without the creative labor of those skilled in the art are within the scope of protection of the present invention.

[0020] Additionally, the terms "first" and "second" are merely descriptive, without indicating or implying a relative importance or a number of technical features being presented. Thus, a feature qualified by "first" or "second" may indicate or imply the inclusion of at least one of the feature. In the present description, "plurality" means at least two, e.g., two, three, etc., unless otherwise specifically limited. In the present description, "how many" means at least two, e.g., two, three, etc., unless otherwise specifically limited.

[0021] As used herein, terms such as "some embodiments" refer to embodiments of the invention that may provide beneficial effects in some cases. However, other embodiments may be preferred, in the same or other cases. Moreover, the description of one or more preferred embodiments does not imply that other embodiments cannot be utilized, and is not intended to exclude other embodiments from the scope of the invention.

[0022] When a numerical range is disclosed herein, the range is considered to be continuous and includes the minimum value, the maximum value, and each value between the minimum and maximum values ​​of the range. Furthermore, when a range is an integer, it includes each integer between the minimum and maximum values ​​of the range. Also, when multiple ranges are provided to describe a feature or characteristic, these ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any or all subranges contained therein.

[0023] When describing positional relationships, unless otherwise specified, when a component, e.g., layer, film, or substrate, is considered to be "on" another film layer, it may be directly on the other film layer, or there may be intermediate film layers. Further, when a layer is considered to be "below" another layer, it may be directly below, or there may be one or more intermediate film layers. It should be understood that when a layer is considered to be "between" two layers, it may be the only layer between the two layers, or there may be one or more intermediate layers.

[0024] The use of "including," "having," and "containing" in this description is intended to cover a non-exclusive category and may include additional elements unless express limiting language such as "only," "consisting of," or the like is used.

[0025] Unless stated to the contrary, singular terms may include plurals and should not be construed as having a number of one.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. The terms used in the present specification are only intended to describe specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0027] 1, the present invention provides a solar cell 10, which includes a substrate 100, an emitter layer 110, a first passivation layer 120, and a first anti-reflection layer 130, which are sequentially stacked on one surface of the substrate 100, and a passivation contact structure 140 and a second anti-reflection layer 150, which are sequentially stacked on the other surface of the substrate 100. The material of the first passivation layer 120 includes gallium oxide.

[0028] The above gallium oxide material is used as the passivation layer material, and the passivation layer material has a low interface state density and a high amount of fixed negative charge, which can ensure the strong interface field passivation effect required for the front surface of TOPCon solar cells, and can maintain the high conversion efficiency of TOPCon solar cells. In addition, the above material also has excellent water blocking stability, which effectively avoids the problem of the passivation layer absorbing water and increasing contact resistance, which leads to failure of the solar cell.

[0029] 2, the solar cell 10 further includes a second passivation layer 160. The material of the second passivation layer 160 includes gallium oxide.

[0030] In some embodiments, the material of the first passivation layer 120 and the material of the first passivation layer 120 are one-dimensional β-Ga 2 O 3 It is.

[0031] In addition, selecting gallium oxide as the material for the passivation layer can more effectively absorb ultraviolet light and reduce the H after the solar cell is exposed outdoors for a long period of time. + Improves the stability of the bond energy and H + It improves the stability of passivation and effectively avoids the failure problem of solar cells under strong ultraviolet irradiation. + The bond is SiH 4 , N.H. 3 and (CH 3 ) 3 H produced in the reaction of Ga + Refers to a bond.

[0032] In one specific example, the passivation contact structure 140 includes a tunnel oxide layer 141 and a doped polysilicon layer 142 that are stacked in sequence, with the tunnel oxide layer 141 facing one side of the substrate 100. In some embodiments, the tunnel oxide layer 141 contacts the substrate 100.

[0033] Note that the substrate 100 is a silicon substrate 100 having a first conductivity type, the emitter layer 110 has a second conductivity type, and the doped polysilicon has the first conductivity type. The first conductivity type is N type and the second conductivity type is P type, or the first conductivity type is P type and the second conductivity type is N type.

[0034] Furthermore, the substrate 100 has a first conductivity type. The emitter layer 110 having a second conductivity type is manufactured by diffusing and doping the substrate 100 with boron. The doped polysilicon layer 142 having the first conductivity type is manufactured by diffusing and doping polysilicon with phosphorus.

[0035] Furthermore, the tunnel oxide layer 141 is a silicon oxide layer.

[0036] In some embodiments, first antireflective layer 130 and second antireflective layer 150 each independently comprise one or more of a silicon nitride layer, a silicon oxynitride layer, and a silicon oxide layer.

[0037] In some embodiments, the first antireflective layer 130 includes one or more of a first silicon nitride layer 131, a silicon oxynitride layer 132, and a silicon oxide layer. In some embodiments, the first antireflective layer 130 includes a first silicon nitride layer 131 in contact with the first passivation layer 120.

[0038] In some embodiments, the second anti-reflective layer 150 includes a second silicon nitride layer 151. Specifically, the second silicon nitride layer contacts a second passivation layer 160.

[0039] In addition, by selecting gallium oxide as the first passivation layer 120 and forming a first gallium nitride layer on the first passivation layer 120, the chemical passivation and field passivation of the cell surface can be strengthened, and the minority carrier lifetime and conversion efficiency of the solar cell can be effectively improved.

[0040] In one specific example, the solar cell further includes a first electrode 170 and a second electrode 180. The first electrode 170 connects to the emitter layer 110 through the first passivation layer 120 and the first anti-reflective layer 130. The second electrode 180 connects to the passivation contact structure 140 through the second anti-reflective layer 150.

[0041] Furthermore, the materials of the first electrode 170 and the second electrode 180 each independently include silver, aluminum, and gold.

[0042] In addition, silver and aluminum are selected as the metal electrodes, and are often manufactured by screen printing with metal paste during manufacturing, but the passivation layer material is prone to water absorption, and the alloy formed from the paste is prone to oxidation, increasing the contact resistance and causing the battery to fail. By using a passivation layer material with excellent water blocking stability, the sensitivity of TOPCon solar cells to high temperature and high humidity environments can be effectively suppressed, and the reliability of the battery can be effectively improved.

[0043] Furthermore, the present invention further provides a method for manufacturing the above-mentioned solar cell, which includes the steps of sequentially fabricating an emitter layer 110, a first passivation layer 120 and a first anti-reflection layer 130 on one side surface of the substrate 100, and sequentially fabricating a passivation contact structure 140 and a second anti-reflection layer 150 on the other side surface of the substrate 100.

[0044] In addition, the surface of the silicon wafer having the first conductivity type is textured to remove surface damage and impurities caused during the cutting process of the silicon wafer, and to increase the bonding area through diffusion, thereby increasing the surface area of ​​the battery cell. The reflectance of the surface of the battery cell is reduced through the principle of light confinement. As for the texture, one or both sides of the substrate 100 may be textured according to need, and in some embodiments, the silicon wafer is N-type.

[0045] Further, a second conductive type atom diffusion is performed on the front side of the substrate 100 to form an emitter layer 110 having the second conductive type, and then laser doping is performed. In some embodiments, boron diffusion is performed on the surface of the substrate 100. The boron diffusion conditions are BCl 3 This involves using as a boron source and performing diffusion at a temperature of 950°C to 1000°C.

[0046] In addition, in the case of a boron-diffused selective emitter (SE) structure battery, the contact area (electrode contact area) between the metal gate line and the silicon wafer on the boron-diffused surface is heavily doped, but the non-metallic contact area between the metal electrodes is lightly doped. This structure effectively reduces the contact resistance and metal complexation in the metal area, increasing the open circuit voltage. It also reduces Auger recombination in the lightly doped non-metallic contact area, effectively improving the quantum efficiency at short wavelengths, and thus increasing the short circuit current.

[0047] The method further includes subjecting the doped region to a high temperature process after the laser doping to restore the doped region to a high temperature.

[0048] In one specific example, after high temperature recovery, the borosilicate glass (BSG) wrapped around the edge and the back side of the substrate 100 is removed by a chain method. After this process, a groove-type back side polishing process is performed, in which the edge and back side of the substrate 100 are alkaline etched to remove the wrapping and polish the back side.

[0049] After the above steps, a tunnel oxide layer 141 and a polysilicon layer are sequentially manufactured on the other surface of the silicon wafer, that is, the back surface. Specifically, the silicon oxide layer may be manufactured as the tunnel oxide layer 141 and the polysilicon layer by, but not limited to, a low pressure chemical vapor deposition method (LPCVD). Then, a phosphorus diffusion doping process is performed on the polysilicon layer on the back surface to manufacture a doped polysilicon layer 142, and then an annealing process is performed to crystallize the polysilicon.

[0050] In one specific example, after phosphorus diffusion and annealing, the chains remove the phosphosilicate glass (PSG) wrapped around the edges and the front side of the substrate 100. This is followed by trench polysilicon removal and an RCA clean, which is an industry standard wet cleaning process, followed by alkaline polishing to remove the polysilicon wrapped around the front and edges, and hydrofluoric acid to remove the borosilicate glass (BSG) on the front side.

[0051] In one specific example, before manufacturing the second anti-reflection layer 150, the passivation structure further includes a step of manufacturing a second passivation layer 160.

[0052] In one specific example, the first passivation layer 120 is fabricated by one of atomic layer deposition, plasma enhanced chemical vapor deposition, and physical vapor deposition.

[0053] Furthermore, the methods for fabricating the first passivation layer 120 and the second passivation layer 160 are each independently selected from one of atomic layer deposition, plasma enhanced chemical vapor deposition, and physical vapor deposition.

[0054] In some embodiments, the first passivation layer 120 and the second passivation layer 160 are fabricated by atomic layer deposition (ALD) using trimethylgallium and an oxygen-containing material.

[0055] Specifically, the steps of manufacturing the first passivation layer 120 and the second passivation layer 160 by atomic layer deposition include loading the boat, first vacuuming, heating to the process temperature and subsequent heat retention, leak detection, pre-venting, trimethylgallium deposition, trimethylgallium thermal decomposition reaction, trimethylgallium cleaning treatment, first constant temperature, ozone deposition, ozone thermal decomposition reaction, ozone cleaning treatment, second constant temperature, second vacuuming, furnace tube cleaning, returning to normal pressure, and loading the boat.

[0056] In one specific embodiment, the step of depositing the gallium oxide passivation layer to various thicknesses includes repeatedly performing the steps of trimethylgallium deposition, trimethylgallium thermal decomposition, trimethylgallium cleaning, a first constant temperature, ozone deposition, ozone thermal decomposition, ozone cleaning, and a second constant temperature. The number of repetitions is set as needed, and is 20 to 40 times. In some embodiments, the number of repetitions is 25 to 35 times, and may be specifically, but not limited to, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, or 35 times.

[0057] In one specific example, the conditions for producing the first passivation layer 120 and the second passivation layer 160 by atomic layer deposition each independently include a reaction temperature of 210°C to 230°C and a reaction pressure of 20 torr to 35 torr in an atmosphere of 3000 sccm to 12000 sccm of trimethylgallium and 4000 sccm to 12000 sccm of ozone.

[0058] Specifically, the conditions for board loading include sending a silicon wafer into the device, a set time of 100 s to 140 s, and a set temperature of 230°C to 270°C.

[0059] Furthermore, the conditions for the first evacuation include a set time of 180 s to 240 s, a set temperature of 200° C. to 240° C., and a set pressure after evacuation of 25 torr to 35 torr.

[0060] Furthermore, the conditions for heating to the process temperature and subsequent heat retention include re-evacuating the device to the process set point, a set time of 280 s to 340 s, a set temperature of 200°C to 240°C, and a set pressure after evacuation of 25 torr to 35 torr.

[0061] Next, perform leak detection to detect whether the vacuum leaks, so as to easily ensure the process effect before introducing the process gas, the set time is 18s to 24s, the set temperature is 200℃ to 240℃, and the set pressure after evacuation is 25torr to 35torr.

[0062] A pre-aeration process is performed. The conditions of the pre-aeration process include a set time of 8 s to 14 s, a flow rate of trimethylgallium of 8000 sccm to 12000 sccm, and a flow rate of ozone of 8000 sccm to 12000 sccm.

[0063] The conditions for trimethylgallium deposition include a trimethylgallium flow rate of 3000sccm to 8000sccm, a reaction pressure of 20torr to 30torr, a reaction temperature of 210°C to 230°C, and a set time of 2000ms to 6000ms.

[0064] Further, the conditions for the trimethylgallium deposition include a flow rate of trimethylgallium of 4000sccm to 6000sccm, a reaction pressure of 22torr to 27torr, a reaction temperature of 215°C to 225°C, and a set time of 3000ms to 5000ms.

[0065] The conditions for the trimethylgallium thermal decomposition reaction include a reaction pressure of 20 torr to 30 torr, a reaction temperature of 210° C. to 230° C., and a set time of 2000 ms to 5000 ms.

[0066] In some embodiments, the conditions for the trimethylgallium pyrolysis reaction include a reaction pressure of 22 torr to 27 torr, a reaction temperature of 210° C. to 230° C., and a set time of 2000 ms to 4000 ms.

[0067] The conditions for performing the cleaning treatment on trimethylgallium include an introduction flow rate of trimethylgallium of 8000sccm to 12000sccm, an introduction flow rate of ozone of 8000sccm to 12000sccm, a set pressure of 20torr to 30torr, a set temperature of 210°C to 230°C, and a set time of 4000ms to 8000ms.

[0068] Furthermore, the conditions for performing the cleaning treatment on trimethylgallium include an introduction flow rate of trimethylgallium of 9000sccm to 11000sccm, an introduction flow rate of ozone of 9000sccm to 11000sccm, a set pressure of 22torr to 27torr, a set temperature of 215°C to 225°C, and a set time of 5500ms to 7500ms.

[0069] The conditions for the first constant temperature include waiting until all the gas in the furnace tube is extracted, setting time of 1000ms to 3000ms, setting pressure of 25torr to 35torr, and setting temperature of 210℃ to 230℃.

[0070] In one specific example, the conditions for the first constant temperature include a set time of 1500 ms to 2500 ms, a set pressure of 28 torr to 32 torr, and a set temperature of 215°C to 225°C.

[0071] The conditions of ozone deposition include an ozone flow rate of 3000sccm-8000sccm, a reaction pressure of 20torr-30torr, a reaction temperature of 210℃-230℃, and a set time of 4000ms-8000ms.

[0072] Further, the conditions of the ozone deposition include an ozone flow rate of 5000sccm to 7000sccm, a reaction pressure of 22torr to 27torr, a reaction temperature of 215°C to 225°C, and a set time of 5000ms to 7000ms.

[0073] The conditions for the ozone pyrolysis reaction include a reaction pressure of 20 torr to 30 torr, a reaction temperature of 210° C. to 230° C., and a set time of 300 ms to 700 ms.

[0074] Further, the conditions for the ozone thermal decomposition reaction include a reaction pressure of 22 torr to 27 torr, a reaction temperature of 215° C. to 225° C., and a set time of 400 ms to 600 ms.

[0075] The conditions for performing the cleaning treatment with ozone include an introduction flow rate of trimethylgallium of 8000sccm to 12000sccm, an introduction flow rate of ozone of 8000sccm to 12000sccm, a set pressure of 20torr to 30torr, a set temperature of 210°C to 230°C, and a set time of 2000ms to 6000ms.

[0076] In some embodiments, the conditions for performing the cleaning process with ozone include an introduction flow rate of trimethylgallium of 9000 sccm to 11000 sccm, an introduction flow rate of ozone of 9000 sccm to 11000 sccm, a set pressure of 22 torr to 27 torr, a set temperature of 215° C. to 225° C., and a set time of 3000 ms to 5000 ms.

[0077] The conditions for the second constant temperature include waiting until all the gas in the furnace tube is extracted, setting time of 1000ms to 3000ms, setting pressure of 25torr to 35torr, and setting temperature of 210℃ to 230℃.

[0078] Furthermore, the conditions for the second constant temperature include a set time of 1500 ms to 2500 ms, a set pressure of 28 torr to 32 torr, and a set temperature of 210°C to 230°C.

[0079] After the second constant temperature, a second evacuation is performed. The conditions for the second evacuation include a set time of 10 s to 40 s, a set temperature of 220°C to 270°C, and a set pressure after evacuation of 15 torr to 25 torr.

[0080] The conditions for cleaning the furnace tube after the second evacuation and blowing out the residual gas in the furnace include a set time of 10s to 30s, a set temperature of 220°C to 270°C, a set pressure after evacuation of 15 torr to 25 torr, and an inert gas flow rate of 20,000sccm to 30,000sccm.

[0081] Thereafter, the device is returned to normal pressure setting, and the conditions for opening the furnace door include a set time of 100 s to 300 s, a set temperature of 220° C. to 270° C., and an inert gas flow rate of 30,000 sccm to 70,000 sccm.

[0082] Finally, the conditions for unloading the boat and removing the sample include a set time of 100 s to 150 s and a set temperature of 220°C to 270°C.

[0083] Furthermore, the first anti-reflective layer 130 and the second anti-reflective layer 150 may be manufactured by, but not limited to, plasma-enhanced chemical vapor deposition (PECVD).

[0084] Furthermore, the first electrode 170 and the second electrode 180 may be manufactured by a screen printing method, specifically, by printing electrode paste on both sides of the substrate, respectively, and sintering the electrodes to bring them into contact with each other, but is not limited thereto.

[0085] In addition, after the first electrode 170 and the second electrode 180 are manufactured, the method further includes a step of injecting carriers to realize hydrogen passivation and applying a light incidence step to perform a light attenuation prevention treatment.

[0086] Furthermore, there is provided an electric device powered by the solar cell, which may be, but is not limited to, a transformer, a reactor, a capacitor, a composite electric device, a breaker, a detector, a lightning arrester, a coupling capacitor, a power transmission line, a power cable, a grounding device, a generator, a phase modifier, a motor, a sealed busbar, and a thyristor.

[0087] Hereinafter, specific examples will be provided to further explain the solar cell according to the present invention.

[0088] Example 1 As shown in Fig. 3, the present invention provides a solar cell. The solar cell includes an N-type silicon substrate, a P-type emitter layer formed by boron diffusion on one side surface of the N-type silicon substrate, a first passivation layer made of gallium oxide, a first anti-reflection layer made of silicon nitride, silicon oxynitride, and silicon oxide formed on the first passivation layer, and a second anti-reflection layer made of a tunnel oxide layer, a doped polysilicon layer formed by phosphorus diffusion, and silicon nitride formed on the other side surface of the N-type silicon substrate. The one-dimensional β-Ga 2 O 3 The steps of forming the structure are as follows: Step 1: A boat was brought in, a silicon wafer was placed on an aluminum supporting jig, and the wafer was then fed into the ALD apparatus by a robot arm. The time was set to 120 s and the temperature to 250°C. Step 2: A vacuum was pulled and the furnace tube was evacuated for the first time at a time of 200 s, a temperature of 220° C., and a pressure of 30 torr. Step 3: Heating was performed, and the pressure was evacuated to the process set point, while the furnace tube was kept at a constant temperature, the time was 300 s, the temperature was 220° C., and the pressure was 30 torr. Step 4: Perform leak detection to check whether the vacuum leaks, to easily ensure the process effect before introducing the process gas, the time was 20 s, the temperature was 220 °C, and the pressure was 30 torr. Step 5: Pre-aeration was performed in the gas pipeline. The pre-aeration time was set to 10 s, and trimethyl gallium (TMGa) was introduced at a flow rate of 10,000 sccm, and ozone (O3) was introduced at a flow rate of 10,000 sccm. Step 6: Trimethylgallium (TMGa) was introduced and pyrolytically deposited at a time of 4000 ms, a temperature of 220° C., a pressure of 25 torr, and a flow rate of 5000 sccm. Step 7: The thermal decomposition reaction of trimethylgallium (TMGa) was allowed to stabilize for 3000 ms at a temperature of 220° C. and a pressure of 25 torr. Step 8: Trimethylgallium (TMGa) is cleaned for 6500 ms, the temperature is 220° C., the pressure is 25 torr, TMGa is introduced at a flow rate of 10000 sccm, and ozone (O 3 ) was introduced at a flow rate of 10,000 sccm. Step 9: The temperature in the furnace tube was allowed to stabilize until the gas in the furnace tube was completely extracted. The time was 2000 ms, the temperature was 220° C., and the pressure was 30 torr. Step 10: Ozone (O 3 ) was introduced for pyrolysis deposition, the time was 6000 ms, the temperature was 220°C, the pressure was 25 torr, and ozone (O 3 ) was introduced at a flow rate of 6000 sccm. Step 11: Ozone (O 3 The thermal decomposition reaction of ) was allowed to stabilize, and the reaction time was set to 500 ms, the temperature to 220° C., and the pressure to 25 torr. Step 12: Ozone (O 3 ) was subjected to a cleaning process, with the time set to 4000 ms, the temperature set to 220°C, the pressure set to 25 torr, trimethylgallium (TMGa) was introduced at a flow rate of 10000 sccm, and ozone (O 3 ) was introduced at a flow rate of 10,000 sccm. Step 13: The temperature in the furnace tube was stabilized until the gas in the furnace tube was completely extracted. The time was 2000 ms, the temperature was 220° C., and the pressure was 30 torr. It should be noted that steps 6 to 13 constitute one cycle reaction, and 30 cycles are required to deposit the gallium oxide medium layer. Step 14: A vacuum was applied to extract excess gas, the time was 25 s, the temperature was 250° C., and the pressure was 20 torr. Step 15: The furnace tube was cleaned and residual gas was blown out, the time was 15 s, the temperature was 250° C., the pressure was 20 torr, and the nitrogen gas flow rate was 25000 sccm. Step 16: Return to normal pressure, prepare the furnace door to open, set the time to 200 s, set the temperature to 250 °C, and use N 2 was introduced at a flow rate of 50,000 sccm. Step 17: The boat was removed, and the aluminum support jig was taken out of the cavity of the ALD reactor by the robot arm. The time was set to 120 s, and the temperature was set to 250° C.

[0089] Example 2 As shown in Figure 4, this embodiment provides a solar cell, which is based on Example 1, in which gallium oxide is formed as a second passivation layer between the doped polysilicon layer and the second anti-reflection layer, and the manufacturing method of the second passivation layer is the same as that of the first passivation layer.

[0090] Example 3 As shown in Fig. 5, this embodiment provides a solar cell, which differs from the solar cell of embodiment 2 in that the structure of the first passivation layer and the first anti-reflection layer is a gallium oxide layer, a silicon nitride layer and a silicon oxynitride layer that are sequentially stacked.

[0091] Example 4 As shown in Fig. 6, the present invention provides a solar cell, which is different from Example 2 in that the structure of the first passivation layer and the first anti-reflection layer is a gallium oxide layer, a silicon nitride layer and a silicon oxide layer that are sequentially stacked.

[0092] Comparative Example 1 This comparative example provides a solar cell, which differs from Example 1 in that the material of the first passivation layer is aluminum oxide.

[0093] Comparative Example 2 This comparative example provides a solar cell, which differs from Example 2 in that the material of the first passivation layer and the material of the second passivation layer are aluminum oxide.

[0094] Comparative Example 3 This comparative example provides a solar cell, which is different from Example 2 in that the structure of a first passivation layer and a first anti-reflection layer is a gallium oxide layer, a silicon oxynitride layer and a silicon oxide layer that are stacked in sequence.

[0095] Comparative Example 4 This comparative example provides a solar cell, which differs from Example 2 in that the structure of a first passivation layer and a first anti-reflection layer is a gallium oxide layer and a silicon oxynitride layer that are sequentially stacked.

[0096] Comparative Example 5 This comparative example provides a solar cell, which differs from Example 2 in that the structure of a first passivation layer and a first anti-reflection layer is a gallium oxide layer and a silicon oxide layer that are sequentially stacked.

[0097] For the solar cells according to Examples 1 to 4 and Comparative Examples 1 to 5, parameters such as the solar cell conversion efficiency (Eta), open circuit voltage (Uoc), short circuit current (Isc), fill factor (FF), maximum operating voltage (Umpp), maximum operating current (Impp), maximum operating power (Pmpp), and power loss were measured. The measurement method was performed with reference to IEC TS 63202-3 Photovoltaic cells-Part 3: Measurement of current-voltage characteristics of bicial photovoltaic cells issued by the International Electrotechnical Commission.

[0098] The conversion efficiencies of the solar cells according to the above examples and comparative examples were measured, and the results are shown in Table 1.

[0099] JPEG2025515538000002.jpg32170

[0100] According to Table 1, the introduction of gallium oxide media layer material did not affect the final conversion efficiency of the TOPCon solar cell, which still remained high at a level of 25%.

[0101] The solar cells according to the above-mentioned examples and comparative examples were measured at a temperature of 85° C. and a humidity of 85%. The results are shown in Table 2.

[0102] JPEG2025515538000003.jpg102170

[0103] Thus, after replacing the passivation layer material, the performance of TOPCon solar cells in high temperature and high humidity environments is significantly improved, effectively improving the reliability of the devices.

[0104] The solar cells according to the above-mentioned examples and comparative examples were subjected to measurement of UV light attenuation for 200 hours. The results are shown in Table 3.

[0105] JPEG2025515538000004.jpg49170

[0106] According to Table 3, after replacing the passivation layer material, the TOPCon solar cell maintains excellent device performance even when exposed to UV irradiation for a long time.

[0107] Thus, gallium oxide has a low interface state density and a high fixed negative charge, which not only ensures the strong interface field passivation effect required for the front surface of TOPCon solar cells, but also maintains the high conversion efficiency of TOPCon solar cells. In addition, the above material also has excellent water blocking stability, effectively avoiding the problem of the contact resistance increasing after the passivation layer absorbs water, which leads to the failure of the solar cell. Choosing gallium oxide as the passivation layer material can effectively absorb ultraviolet light and reduce the H2O after the solar cell is exposed outdoors for a long period of time. + Improves the stability of the bond energy and H + Improve the stability of passivation and effectively avoid the failure of solar cells under strong ultraviolet irradiation.

[0108] Furthermore, cell structures in which gallium oxide is installed as a passivation layer on both sides of the substrate of a TOPCon solar cell were compared, and the performance of the solar cells of Examples 2 to 4 and Comparative Examples 3 to 5 was measured by installing different first antireflection layer structures, and the measurement results are shown in Table 4. The measurement results show that the composite passivation structure obtained by contacting gallium oxide in the passivation layer with silicon nitride in the antireflection layer strengthens the chemical passivation and field passivation of the cell surface, and effectively improves the minority carrier lifetime and conversion efficiency of the solar cell.

[0109] JPEG2025515538000005.jpg45170

[0110] The technical features of the above-mentioned embodiments can be combined in any combination. For the sake of brevity, all possible combinations of the technical features in the above-mentioned embodiments are not described, but the combinations of these technical features should be considered within the scope of the present specification unless they are inconsistent.

[0111] The above examples merely show some embodiments of the present invention. Although the description is relatively specific and detailed, it should not be understood as limiting the scope of the utility model. It should be noted that a person skilled in the art can further make some modifications and improvements without departing from the concept of the present invention, all of which are within the scope of protection of the present application. Therefore, the scope of protection of the patent of the present invention shall be subject to the appended claims.

[0112] Explanation of symbols 10. Solar Cells 100 Substrates 110 Emitter layer 120 First passivation layer 130 1st anti-reflection layer 131 First silicon nitride layer 132 Silicon Oxynitride 133 Silicon oxide 140 Passivation Contact Structure 141 Tunnel oxide layer 142 Doped polysilicon layer 150 Second anti-reflection layer 151 Second silicon nitride layer 160 Second passivation layer 170 1st electrode 180 2nd electrode

Claims

1. A solar cell comprising: A substrate; an emitter layer, a first passivation layer, and a first anti-reflection layer, which are sequentially stacked on one surface of the substrate; a passivation contact structure and a second anti-reflection layer sequentially stacked on the other surface of the substrate; A solar cell, wherein the material of the first passivation layer contains gallium oxide.

2. a second passivation layer disposed between the passivation contact structure and the second anti-reflection layer; 2. The solar cell according to claim 1, wherein the material of the second passivation layer includes gallium oxide.

3. the passivation contact structure includes a tunnel oxide layer and a doped polysilicon layer stacked in sequence; The solar cell of claim 1 , wherein the tunnel oxide layer faces one side of the substrate.

4. The solar cell according to claim 1 , wherein the first anti-reflection layer and the second anti-reflection layer each independently include at least one of a silicon nitride layer, a silicon oxynitride layer, and a silicon oxide layer.

5. the first anti-reflective layer comprises a first silicon nitride layer; The solar cell of claim 4 , wherein the first silicon nitride layer is in contact with the first passivation layer.

6. further comprising a first electrode and a second electrode; the first electrode passes through the first passivation layer and the first antireflection layer and is connected to the emitter layer; The solar cell according to any one of claims 1 to 5, wherein the second electrode penetrates the second anti-reflection layer and is connected to the passivation contact structure.

7. A method for producing a solar cell according to any one of claims 1 to 6, comprising the steps of: forming the emitter layer, the first passivation layer and the first anti-reflection layer on one side surface of the substrate; and sequentially forming the passivation contact structure and the second anti-reflection layer on the other surface of the substrate.

8. 8. The method of claim 7, wherein the first passivation layer is fabricated by one of atomic layer deposition, plasma enhanced chemical vapor deposition, and physical vapor deposition.

9. The method for producing the solar cell according to claim 7, characterized in that the conditions for producing the first passivation layer and the second passivation layer by atomic layer deposition each independently include a reaction temperature of 210°C to 230°C and a reaction pressure of 20 torr to 35 torr in an atmosphere of 3000 sccm to 12000 sccm of trimethylgallium and 4000 sccm to 12000 sccm of ozone.

10. 1. An electrical device comprising: An electrical device comprising the solar cell according to any one of claims 1 to 6 as a power source.

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