A composite film used as a tunnel passivation layer for crystalline silicon photovoltaic cells and a preparation device

Abstract

The present invention discloses a composite film used as a tunnel passivation layer of a crystalline silicon photovoltaic cell and a preparation device, which relates to the technical field of photovoltaic cell production, including a reaction chamber composed of a bottom plate and an upper cover, and also includes a coaxial waveguide, which is installed at the bottom of the reaction chamber, one end of the coaxial waveguide is installed with a rectangular waveguide below the reaction chamber, and the other end is installed with a base in the reaction chamber, a quartz glass ring is installed between the base and the bottom plate, and a diffusion-type air intake component is rotatably installed in the upper cover, a diverter bracket is installed in the upper cover, the bottom of the diffusion-type air intake component overlaps the diverter bracket, and the bottom of the diverter bracket is provided with an annular diverter cavity and a central diverter plate located in the annular diverter cavity. Through the design of the diffusion-type air intake component and the diverter bracket, the present invention can evenly distribute the gas to all corners of the reaction chamber, thereby improving the uniformity of the reaction and making the quality of the tunnel passivation layer more stable and reliable.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic cell production, in particular to a composite film used as a tunnel passivation layer for a crystalline silicon photovoltaic cell and a preparation device. Background Art

[0002] As the leading product in the photovoltaic industry, the improvement of the photoelectric conversion efficiency of crystalline silicon photovoltaic cells has always been the focus of research. The tunneling passivation layer, as an important component of photovoltaic cells, plays a key role in improving cell performance and efficiency. The composite film in the tunneling passivation layer is generally processed by vapor deposition equipment, among which plasma vapor deposition is a technology that uses plasma as an energy source to activate the reaction gas to cause it to undergo chemical reactions on the substrate surface or near-surface space, thereby generating a solid film.

[0003] The patent publication number of the existing patent application is: CN106245005A, the publication date is December 21, 2016, and the name of the patent is "Plasma Enhanced Chemical Vapor Deposition Device". The patent includes: a reaction chamber, an opening valve is arranged on the side wall of the reaction chamber; an upper electrode and a lower electrode are arranged relatively inside the reaction chamber; and a radio frequency feeding device, which is electrically connected to the upper electrode and is used to generate a plasma enhanced chemical vapor deposition reaction inside the reaction chamber to form a film layer on the substrate placed on the lower electrode, and the input point of the radio frequency feeding device is located between the center of the upper electrode and the opening valve. The plasma enhanced chemical vapor deposition device of the present invention has a high product yield.

[0004] The above application has shortcomings. Relying on a single method to diffuse the airflow still cannot ensure that the gas distribution in the reaction chamber reaches an ideal state, resulting in uneven reaction and affecting the quality of the composite film. At the same time, the air intake adjustment means are limited and cannot meet the precise control requirements of gas flow distribution in different preparation processes, further affecting the preparation efficiency and product stability. At the same time, the tunneling passivation layer of the currently mass-produced crystalline silicon photovoltaic cells mostly uses silicon oxide, but the density of silicon oxide is only 2.2g / cm3. The low density leads to insufficient density in blocking the doped atoms, and also leads to the inability to completely eliminate the surface dangling bonds of the crystalline silicon substrate, and also leads to a high content of hydrogen atoms inside it, resulting in photothermal attenuation problems. Summary of the invention

[0005] The object of the present invention is to provide a composite film used as a tunnel passivation layer of a crystalline silicon photovoltaic cell and a preparation device to solve the deficiencies in the above-mentioned prior art.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A composite film used as a tunnel passivation layer of a crystalline silicon photovoltaic cell, characterized in that the composite film is composed of silicon oxide and zirconium oxide, and the silicon oxide and zirconium oxide are uniformly distributed in the composite film.

[0008] Preferably, the composite film is formed by alternately stacking or mixing silicon oxide and zirconium oxide.

[0009] Preferably, the composite film is prepared by, but not limited to, chemical vapor deposition (CVD) or plasma enhanced CVD (PECVD).

[0010] A device for preparing the composite film used as a tunnel passivation layer for a crystalline silicon photovoltaic cell comprises a reaction chamber composed of a bottom plate and an upper cover, and also comprises a coaxial waveguide installed at the bottom of the reaction chamber, one end of the coaxial waveguide is provided with a rectangular waveguide below the reaction chamber, and the other end is provided with a base in the reaction chamber, a quartz glass ring is installed between the base and the bottom plate, a diffusion air intake component is rotatably installed in the upper cover, a diverter bracket is installed in the upper cover, the bottom of the diffusion air intake component is overlapped with the diverter bracket, the bottom of the diverter bracket is provided with an annular diverter cavity and a central diverter disk located in the annular diverter cavity, a plurality of diverter regulating valves are respectively located at a plurality of connecting points between the annular diverter cavity and the diverter bracket, and the diffusion air intake component is transmission-connected to the diverter regulating valve, and when the diffusion air intake component rotates, the diverter regulating valve is driven to open and close.

[0011] Preferably, the diffuser-type air intake assembly comprises an air intake pipe inserted into the top of the upper cover, the bottom end of the air intake pipe is fixedly connected to a guide cover, the bottom of the guide cover is fixedly connected to a lap plate, and an air intake dispersion piece is elastically installed through the lap plate.

[0012] Preferably, the air intake dispersion component includes an insertion rod inserted in the center of the lap plate, the top of the insertion rod is fixedly connected to a plug cover for sealing the intake pipe, a return spring is installed between the plug cover and the lap plate, and the bottom of the insertion rod is fixedly connected to a guide plate below the lap plate.

[0013] Preferably, a plurality of gas delivery grooves are fixedly connected to the outer wall of the diverter bracket, the annular diverter cavity is connected to the interior of the diverter bracket through the gas delivery grooves, and the gas inlet ends of the gas delivery grooves are located above the central diverter plate.

[0014] Preferably, the diverter regulating valve includes a shaft rotatably mounted on the inner wall of the diverter bracket, a friction wheel is fixedly connected to the top of the shaft, the outer side of the lap plate is in contact with the friction wheel, a screw rod is fixedly connected to the bottom of the shaft, a valve plate covering the air inlet end of the air delivery groove is slidably connected to the inner wall of the diverter bracket, and the screw rod is threadedly connected to the valve plate.

[0015] Preferably, a connecting ring is rotatably mounted on the bottom of the annular diversion chamber, and a plurality of airflow blocking plates are annularly distributed on the outer wall of the connecting ring, and the airflow blocking plates are located below the air delivery groove.

[0016] Preferably, the bottom end of the screw rod is fixedly connected with a transmission gear in the annular diversion cavity, and the connecting ring is fixedly connected with a gear ring meshing with the transmission gear.

[0017] In the above technical scheme, through the design of the diffusion-type air intake assembly and the diverter bracket, the gas can be evenly distributed to all corners of the reaction chamber, thereby improving the uniformity of the reaction and making the quality of the tunneling passivation layer more stable and reliable. At the same time, the diffusion-type air intake assembly can drive multiple diverter regulating valves to open and close, so that the air intake volume on the side of the diverter bracket can be precisely controlled according to actual needs, thereby optimizing the reaction conditions, adjusting the air flow diffusion scheme, and improving production efficiency and product quality in a targeted manner. At the same time, zirconium oxide has an extremely high density and can remain stable at 2200-2500°C. At the same time, zirconium oxide has high hardness, high strength and good toughness, and is low in cost. It is a common material in crystalline silicon industry equipment. The introduction of trace zirconium impurities in crystalline silicon has a negligible effect on the photoelectric properties of crystalline silicon. Therefore, zirconium oxide is very suitable for forming a composite film with silicon oxide and used as a tunneling passivation layer for crystalline silicon photovoltaic cells.

[0018] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

[0019] This application document provides an overview of various implementations or examples of the technology described in the present disclosure, and is not a comprehensive disclosure of the entire scope or all features of the disclosed technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0021] Figure 1 The overall structure schematic diagram of a preparation device for a composite film used as a tunnel passivation layer for a crystalline silicon photovoltaic cell according to the present invention;

[0022] Figure 2 It is an overall cross-sectional view of a preparation device for a composite film used as a tunnel passivation layer for a crystalline silicon photovoltaic cell according to the present invention;

[0023] Figure 3 It is a schematic diagram of the connection between the diffusion-type air inlet assembly and the diversion bracket in the preparation equipment of the composite film used as the tunnel passivation layer of the crystalline silicon photovoltaic cell of the present invention;

[0024] Figure 4 It is a schematic diagram of the internal structure of a diffusion-type air intake assembly in a device for preparing a composite film used as a tunneling passivation layer for a crystalline silicon photovoltaic cell according to the present invention;

[0025] Figure 5 It is a structural schematic diagram of a shunt bracket and a shunt regulating valve in a preparation device for a composite film used as a tunnel passivation layer for a crystalline silicon photovoltaic cell according to the present invention;

[0026] Figure 6 It is a transmission schematic diagram of a shunt regulating valve, a diffusion-type air intake assembly, and a gear ring in a preparation device for a composite film used as a tunnel passivation layer for a crystalline silicon photovoltaic cell according to the present invention;

[0027] Figure 7 for Figure 6 A magnified view of the structure at center;

[0028] Figure 8 The invention relates to an air inlet dispersion component in a preparation device for a composite film used as a tunnel passivation layer of a crystalline silicon photovoltaic cell.

[0029] Description of reference numerals:

[0030] 1. Reaction chamber; 101. Bottom plate; 102. Upper cover; 2. Coaxial waveguide; 201. Rectangular waveguide; 202. Base; 203. Quartz glass ring; 3. Diffusion air intake assembly; 301. Air intake pipe; 302. Air guide cover; 303. Lap plate; 304. Limit rod; 4. Diverter bracket; 401. Annular diverter cavity; 402. Central diverter plate; 403. Gas delivery trough; 5. Diverter regulating valve; 501. Shaft; 502. Friction wheel; 503. Screw rod; 504. Valve plate; 505. Transmission gear; 6. Air intake dispersion member; 601. Insert rod; 602. Plug cover; 603. Reset top spring; 604. Air guide plate; 7. Connecting ring; 701. Airflow baffle; 702. Gear ring. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0032] An embodiment of the present invention provides a composite film used as a tunnel passivation layer of a crystalline silicon photovoltaic cell, characterized in that the composite film is composed of silicon oxide and zirconium oxide, and the silicon oxide and zirconium oxide are uniformly distributed in the composite film.

[0033] Specifically, the tunneling passivation layer of mass-produced crystalline silicon photovoltaic cells currently mostly uses silicon oxide, but the density of silicon oxide is only 2.2g / cm3. The low density leads to insufficient density in blocking doped atoms, and also leads to its inability to completely eliminate the surface dangling bonds of the crystalline silicon substrate, and also leads to a high content of hydrogen atoms inside, resulting in photothermal attenuation problems. In addition, the silicon oxide film is prone to lose some oxygen atoms in the high-temperature process, and the area that loses oxygen atoms will be converted into amorphous silicon or polycrystalline silicon, which will damage its ability to select photogenerated carriers and hinder the diffusion of doped polycrystalline silicon film components to the crystalline silicon substrate. In order to further improve the production yield and performance of crystalline silicon photovoltaic cells, it is necessary to improve the density and high-temperature stability of the tunneling passivation layer. In this application, a composite film of silicon oxide and zirconium oxide is sandwiched between the crystalline silicon substrate and the doped polycrystalline silicon film as a junction tunneling passivation layer to improve the performance of crystalline silicon photovoltaic cells. The density of zirconium oxide (ZrO2) is extremely high, which is 5.89g / cm 3 , the melting point is as high as 2700℃, and it can remain stable at 2200-2500℃, which is much better than silicon dioxide. At the same time, zirconium oxide has high hardness, high strength and good toughness, and is low in cost. It is a common material in crystalline silicon industry equipment. The effect of introducing trace zirconium impurities into crystalline silicon on the photoelectric properties of crystalline silicon is usually negligible. Therefore, zirconium oxide is very suitable for forming a composite film with silicon oxide and used as a tunnel passivation layer for crystalline silicon photovoltaic cells.

[0034] In a further embodiment of the present invention, the composite film is formed by alternately stacking or mixing silicon oxide and zirconium oxide. Specifically, the composite film of silicon oxide and zirconium oxide refers to a multilayer film of alternately stacking silicon oxide and zirconium oxide, and also refers to a uniformly mixed film of silicon oxide and zirconium oxide, wherein silicon oxide is also called silicon dioxide, and zirconium oxide is also called zirconium dioxide. By alternately stacking or uniformly mixing silicon oxide and zirconium oxide, the complementary advantages of the two in chemical stability and electrical properties are utilized to form a film with excellent tunneling passivation effect. The silicon oxide layer provides good insulation and chemical stability, while the zirconium oxide layer enhances the mechanical strength and thermal stability of the film. The two work synergistically to effectively improve the efficiency and stability of crystalline silicon photovoltaic cells.

[0035] In a further embodiment of the present invention, the composite film includes but is not limited to being prepared by chemical vapor deposition (CVD) and plasma enhanced CVD (PECVD). Specifically, in the specific preparation process, a thin silicon oxide layer is first deposited on the surface of the crystalline silicon photovoltaic cell using chemical vapor deposition (CVD) or plasma enhanced CVD (PECVD) technology, and then a zirconium oxide layer is deposited thereon, and this process is performed alternately until the desired film thickness and number of layers are reached. In addition, this embodiment also includes another preparation method, namely, the raw materials of silicon oxide and zirconium oxide are evenly mixed during the preparation process, and then a uniform mixed thin film is formed using the same deposition technology.

[0036] See also Figure 1-8 The present invention provides a device for preparing the composite film used as a tunnel passivation layer of a crystalline silicon photovoltaic cell, comprising a reaction chamber 1 composed of a bottom plate 101 and an upper cover 102, and a coaxial waveguide 2 installed at the bottom of the reaction chamber 1, wherein a rectangular waveguide 201 is installed at one end of the coaxial waveguide 2 below the reaction chamber 1, and a base 202 is installed in the reaction chamber 1 at the other end, and a quartz glass ring 203 is installed between the base 202 and the bottom plate 101, and a diffusion-type air inlet component 3 is rotatably installed. In the upper cover 102, a diverter bracket 4 is installed inside the upper cover 102, the bottom of the diffusion-type air intake component 3 is overlapped with the diverter bracket 4, the bottom of the diverter bracket 4 is provided with an annular diverter cavity 401 and a central diverter disk 402 located in the annular diverter cavity 401, and a plurality of diverter regulating valves 5, which are respectively located at a plurality of connecting points between the annular diverter cavity 401 and the diverter bracket 4, and the diffusion-type air intake component 3 is transmission-connected to the diverter regulating valve 5, and when the diffusion-type air intake component 3 rotates, the diverter regulating valve 5 is driven to open and close.

[0037] Specifically, the coaxial waveguide 2 is firmly installed at the bottom of the base plate 101, one end of which is connected to the external microwave source through the rectangular waveguide 201, and the other end is connected to the base 202 located inside the reaction chamber 1, which is used to uniformly transmit microwave energy to the reaction area. During the preparation process, the reaction chamber 1 is first evacuated to a suitable vacuum state, and the precursor gases of silicon oxide and zirconium oxide are introduced through the diffusion-type air inlet component 3. These gases will be uniformly distributed to the reaction chamber 1 through the annular diverter cavity 401 and the central diverter disk 402 in the diverter bracket 4. There are multiple air holes distributed on the annular diverter cavity 401 and the central diverter disk 402, and can be driven by an external source. The diffusion-type air intake assembly 3 is driven to rotate back and forth, which not only realizes uniform diffusion of the gas, but also accurately controls the change and adjustment of the gas flow in different areas by driving the opening and closing of the diversion regulating valve 5, thereby ensuring the uniform mixing and reaction of the precursor gas in the reaction chamber 1. The microwave energy is transmitted to the base 202 through the coaxial waveguide 2 through the quartz glass ring 203, and the precursor gas is stimulated to undergo a chemical reaction, thereby forming a uniform silicon oxide and zirconium oxide composite film on the surface of the crystalline silicon photovoltaic cell. The composite film exhibits an excellent tunneling passivation effect through the alternating stacking or mixing of silicon oxide and zirconium oxide, which effectively improves the efficiency and stability of the crystalline silicon photovoltaic cell.

[0038] Compared with the prior art, the embodiment of the present invention can evenly distribute the gas to every corner of the reaction chamber 1 through the design of the diffusion-type air intake component 3 and the diverter bracket 4, thereby improving the uniformity of the reaction and making the quality of the tunnel passivation layer more stable and reliable. At the same time, the diffusion-type air intake component 3 can drive multiple diverter regulating valves 5 to open and close, so that the air intake amount on the side of the diverter bracket 4 can be accurately controlled according to actual needs, thereby optimizing the reaction conditions, adjusting the airflow diffusion plan, and improving the production efficiency and product quality in a targeted manner.

[0039] In a further embodiment of the present invention, the diffuser air intake assembly 3 includes an air intake pipe 301 inserted on the top of the upper cover 102, the bottom end of the air intake pipe 301 is fixedly connected to a guide cover 302, the bottom of the guide cover 302 is fixedly connected to a lap plate 303, an air intake dispersion member 6 is elastically installed through the lap plate 303, a plurality of limit rods 304 are installed in the guide cover 302, and the top of the air intake dispersion member 6 is located between the plurality of limit rods 304. Specifically, the guide cover 302 at the bottom end of the air intake pipe 301 helps to evenly diffuse the gas and prevent the gas from directly impacting a certain area of ​​the reaction chamber 1, and the lap plate 303 not only supports the guide cover 302, but also serves as an installation base for the air intake dispersion member 6. The air inlet dispersion member 6 on the top can slightly move to a certain extent as the gas enters, further promoting the uniform distribution of the gas. During the preparation process, the precursor gases of silicon oxide and zirconium oxide enter the air guide cover 302 through the air inlet pipe 301. When gas is transported in the air inlet pipe 301, the air inlet dispersion member 6 is impacted downward. Under the mutual cooperation and guidance of the air guide cover 302 and the air inlet dispersion member 6, the gas is initially diffused, and the gas is dispersed to different directions, promoting the uniform distribution of the gas flow in the reaction chamber 1. At the same time, since the air inlet dispersion member 6 is elastically installed on the lap plate 303, it can slightly move to a certain extent as the gas flow rate changes. This dynamic characteristic helps to further improve the dispersion effect and uniformity of the gas.

[0040] In a further embodiment of the present invention, the air intake dispersion member 6 includes an insertion rod 601 inserted in the center of the lap plate 303, a plug cover 602 for blocking the air intake pipe 301 is fixedly connected to the top of the insertion rod 601, a return spring 603 is installed between the plug cover 602 and the lap plate 303, and a guide plate 604 is fixedly connected to the bottom of the insertion rod 601 below the lap plate 303. Specifically, the size of the plug cover 602 is adapted to the air intake port. When there is no gas delivery in the air intake pipe 301, the return spring 603 pushes the plug cover 602 into the air intake pipe 301 to tightly block the air intake pipe 301. outlet, thereby preventing the gas from directly entering the reaction chamber 1 without being dispersed. At the same time, the return spring enables the plug cover 602 to produce a small up and down displacement when subjected to gas pressure, thereby promoting the dispersion and flow of the gas. The design of the guide plate 604 at the bottom of the plug rod 601 helps to further guide the gas dispersed by the plug cover 602 to all corners of the reaction chamber 1, thereby achieving more uniform gas distribution, improving the gas dispersion effect, and realizing dynamic adjustment of the gas flow rate, thereby ensuring the uniformity and stability of the gas distribution in the reaction chamber 1.

[0041] In a further embodiment of the present invention, a plurality of gas delivery grooves 403 are fixedly connected to the outer wall of the diverter bracket 4, the annular diverter cavity 401 is connected to the inside of the diverter bracket 4 through the gas delivery grooves 403, and the gas inlet end of the gas delivery groove 403 is located above the central diverter disk 402. Specifically, the plurality of gas delivery grooves 403 on the diverter bracket 4 serve as channels for gas circulation, connecting the annular diverter cavity 401 with the inside of the diverter bracket 4, and the gas inlet end of the gas delivery groove 403 is located above the central diverter disk 402, which means that a portion of the gas entering from the inlet pipe 301 enters the return pipe 301 after being dispersed by the central diverter disk 402. The gas flows into the reaction chamber 1, and then the other part is guided to the annular diverter chamber 401 through the gas delivery groove 403, wherein the gas flow blocked by the central diverter plate 402 will also turn to enter the annular diverter chamber 401, reducing the time the gas flow stays in the diverter bracket 4, which not only improves the gas dispersion efficiency, but also ensures the uniform distribution of the gas on the diverter bracket 4. Then, through the layout and flow direction control of the gas delivery groove 403, the gas can enter the reaction chamber 1 in a more uniform and stable manner, thereby improving the uniformity and efficiency of the chemical reaction and reducing the preparation quality problems caused by uneven gas distribution.

[0042] In a further embodiment of the present invention, the shunt regulating valve 5 includes a shaft 501 rotatably mounted on the inner wall of the shunt bracket 4, a friction wheel 502 is fixedly connected to the top of the shaft 501, the outer side of the lap plate 303 is in contact with the friction wheel 502, a screw rod 503 is fixedly connected to the bottom of the shaft 501, a valve plate 504 covering the air inlet end of the gas delivery groove 403 is slidably connected to the inner wall of the shunt bracket 4, and the screw rod 503 is threadedly connected to the valve plate 504. Specifically, the design of the shunt regulating valve 5 realizes the regulation of the gas flow through the annular shunt cavity 401. When the intake dispersion member 6 rotates, the lap plate 303 in the intake dispersion member 6 will drive the friction wheel 502 and the shaft 501 to rotate, and the bottom of the shaft 501 is fixed The connected screw rod 503 rotates accordingly. Since the screw rod 503 is slidably connected to the inner wall of the diverter bracket 4 and the valve plate 504 is threadedly connected, the rotation of the screw rod 503 will drive the valve plate 504 to slide up and down at the air inlet end of the gas delivery groove 403, thereby adjusting the degree of opening of the valve plate 504 to the gas delivery groove 403. This design allows the flow of gas on the side of the base 202 to be dynamically adjusted according to actual needs, ensuring the uniformity and stability of the gas distribution in the reaction chamber 1. In addition, by controlling the reciprocating opening and closing of the valve plate 504 during air intake, the subsequent discharged gas can also push the airflow around the base 202, thereby fully filling the gas in different areas, further optimizing the conditions for the chemical reaction.

[0043] In a further embodiment of the present invention, a connecting ring 7 is rotatably installed at the bottom of the annular diverter chamber 401, and a plurality of airflow blocking plates 701 are distributed in an annular manner on the outer wall of the connecting ring 7, and the airflow blocking plates 701 are located below the gas delivery groove 403. Specifically, when the airflow blocking plates 701 are located below the gas delivery groove 403, the airflow entering the annular diverter chamber 401 will be blocked by the airflow blocking plates 701, guiding the airflow to flow toward both sides, thereby preventing the airflow in the gas delivery groove 403 from being discharged directly through the annular diverter chamber 401.

[0044] In a further embodiment of the present invention, a transmission gear 505 is fixedly connected to the bottom end of the screw rod 503 in the annular diversion chamber 401, and a gear ring 702 meshing with the transmission gear 505 is fixedly connected to the connecting ring 7. Specifically, when the shaft rod 501 rotates due to the rotation of the friction wheel 502, the screw rod 503 will drive the transmission gear 505 to rotate together. Since the transmission gear 505 is meshed with the gear ring 702, the gear ring 702 and the connecting ring 7 will also rotate accordingly. This gear transmission design not only ensures the accuracy and stability of the rotation action, but also realizes the linkage between the valve plate 504 on the screw rod 503 and the airflow barrier 701 on the connecting ring 7. By adjusting the rotation angle of the air intake dispersion member 6, the rotation of the screw rod 503 can be accurately controlled, and then the opening degree of the valve plate 504 to the gas delivery groove 403 and the rotation angle of the connecting ring 7 can be adjusted, thereby realizing dual regulation of the gas flow and further optimization of the airflow distribution.

[0045] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A device for preparing a composite film of a tunnel passivation layer of a crystalline silicon photovoltaic cell, the composite film being composed of silicon oxide and zirconium oxide, and the silicon oxide and zirconium oxide are uniformly distributed in the composite film, the composite film being formed by alternately stacking or mixing silicon oxide and zirconium oxide, the composite film being prepared by chemical vapor deposition or plasma enhanced CVD, the device comprising a reaction chamber (1) consisting of a bottom plate (101) and an upper cover (102), characterized in that: Also includes: A coaxial waveguide (2) is installed at the bottom of the reaction chamber (1), wherein a rectangular waveguide (201) is installed at one end of the coaxial waveguide (2) below the reaction chamber (1), and a base (202) is installed in the reaction chamber (1) at the other end, and a quartz glass ring (203) is installed between the base (202) and the bottom plate (101); A diffusion-type air intake assembly (3) is rotatably mounted in an upper cover (102), a flow splitter bracket (4) is mounted in the upper cover (102), the bottom of the diffusion-type air intake assembly (3) is overlapped with the flow splitter bracket (4), and the bottom of the flow splitter bracket (4) is provided with an annular flow splitter cavity (401) and a central flow splitter plate (402) located in the annular flow splitter cavity (401); A plurality of flow diversion regulating valves (5) are respectively located at a plurality of connecting points between the annular flow diversion chamber (401) and the flow diversion bracket (4), and the diffusion-type air intake component (3) is transmission-connected to the flow diversion regulating valve (5). When the diffusion-type air intake component (3) rotates, the flow diversion regulating valve (5) is driven to open and close.

2. The device for preparing a composite film for a tunnel passivation layer of a crystalline silicon photovoltaic cell according to claim 1, characterized in that: The diffuser air intake assembly (3) comprises an air intake pipe (301) inserted into the top of the upper cover (102); the bottom end of the air intake pipe (301) is fixedly connected to a guide cover (302); the bottom of the guide cover (302) is fixedly connected to a lap plate (303); and an air intake dispersion component (6) is elastically installed through the lap plate (303).

3. The device for preparing a composite film for a tunnel passivation layer of a crystalline silicon photovoltaic cell according to claim 1, characterized in that: The air intake dispersion member (6) comprises an insertion rod (601) inserted in the center of the lap plate (303); a plug cover (602) for blocking the air intake pipe (301) is fixedly connected to the top of the insertion rod (601); a return spring (603) is installed between the plug cover (602) and the lap plate (303); and a guide plate (604) is fixedly connected to the bottom of the insertion rod (601) below the lap plate (303).

4. The device for preparing a composite film for a tunnel passivation layer of a crystalline silicon photovoltaic cell according to claim 2, characterized in that: The outer wall of the diverter bracket (4) is fixedly connected with a plurality of gas delivery grooves (403); the annular diverter cavity (401) is connected to the interior of the diverter bracket (4) via the gas delivery grooves (403); and the gas inlet end of the gas delivery groove (403) is located above the central diverter plate (402).

5. The device for preparing a composite film for a tunnel passivation layer of a crystalline silicon photovoltaic cell according to claim 4, characterized in that: The diversion regulating valve (5) comprises a shaft (501) rotatably mounted on the inner wall of the diversion bracket (4); a friction wheel (502) is fixedly connected to the top of the shaft (501); the outer side of the lap plate (303) is in contact with the friction wheel (502); a screw rod (503) is fixedly connected to the bottom of the shaft (501); a valve plate (504) covering the air inlet end of the air delivery groove (403) is slidably connected to the inner wall of the diversion bracket (4); the screw rod (503) and the valve plate (504) are threadedly connected.

6. The device for preparing a composite film for a tunnel passivation layer of a crystalline silicon photovoltaic cell according to claim 5, characterized in that: A connecting ring (7) is rotatably mounted on the bottom of the annular diversion chamber (401), and a plurality of airflow blocking pieces (701) are distributed in an annular manner on the outer wall of the connecting ring (7), and the airflow blocking pieces (701) are located below the air delivery groove (403).

7. The device for preparing a composite film for a tunnel passivation layer of a crystalline silicon photovoltaic cell according to claim 6, characterized in that: The bottom end of the screw rod (503) is fixedly connected to a transmission gear (505) in the annular diversion chamber (401), and the connecting ring (7) is fixedly connected to a gear ring (702) meshing with the transmission gear (505).

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