Vacuum coating device and system

Abstract

The present application relates to the field of solar cells, and discloses a vacuum coating device and system. A vacuum coating device comprises a first surface coating group, an automatic cell flipping apparatus, a second surface coating group, and a main control unit; the first surface coating group comprises a first inlet end chamber group used for environmental transition, a first PVD magnetron sputtering chamber used for film preparation, and a first outlet end chamber group used for environmental transition; the second surface coating group comprises a second inlet end chamber group used for environmental transition, an RPD coating chamber and a second PVD magnetron sputtering chamber used for film preparation, and a second outlet end chamber group used for environmental transition; the RPD coating chamber and the second PVD magnetron sputtering chamber are used for preparing an RPD+PVD composite TCO film; and the composite TCO film is a laminated composite film in which a PVD film is deposited on the side of an RPD film away from a silicon wafer of a cell. The present application can reduce the preparation cost while ensuring the preparation efficiency and the energy conversion rate of SHJ cells, breaking through the problem of limited production capacity of RPD devices.

Description

Vacuum coating equipment and system Technical Field

[0001] The present application belongs to the field of solar energy technology, relates to the preparation of solar cells, and specifically to a vacuum coating device and system. Background Art

[0002] Currently, PVD (Physical Vapor Deposition) equipment is commonly used to fabricate heterojunction solar cells. However, the conversion efficiency of solar cells produced using PVD equipment is not very ideal. Reactive plasma deposition (RPD) equipment offers significant advantages in fabricating high-efficiency heterojunction solar cells, improving the conversion efficiency of solar cells produced using it by 0.1-0.3% compared to PVD. However, RPD equipment has its own limitations, namely its limited production capacity. Using RPD equipment for all coatings would not meet the demand for large production capacity. Furthermore, increasing production capacity by adding RPD equipment would result in high equipment costs.

[0003] To address these issues, existing technologies combine two deposition processes. Typically, RPD deposition is used to prepare the front-side TCO film for SHJ cells, while PVD is used to prepare the back-side TCO film. This approach improves the energy conversion efficiency of SHJ cells while controlling costs. However, this approach only addresses these issues to a certain extent, not completely. This is because this combination of RPD equipment still requires a large amount of equipment, and due to its limited production capacity, the aforementioned technical issues persist to a certain extent. Utility Model Content

[0004] The present application aims to solve at least one of the technical problems in the above-mentioned related technologies to a certain extent.

[0005] To this end, the purpose of this application is to provide a vacuum coating equipment that can minimize the equipment investment cost while ensuring the conversion efficiency of the prepared battery, and can break through the problem of limited production capacity of RPD equipment.

[0006] In order to solve the above technical problems, this application is implemented as follows:

[0007] The embodiment of the present application provides a vacuum coating device, the device comprising a first-side coating group, an automatic flipping device, a second-side coating group, and a main control unit; the first-side coating group, the automatic flipping device, and the second-side coating group are all connected to the main control unit and operate under the control of the main control unit;

[0008] The first-side coating group includes: a first inlet chamber group for realizing the transition from the external environment to the film forming process environment, a first PVD magnetron sputtering chamber for preparing the TCO film on the first side of the cell, and a first outlet chamber group for realizing the transition from the film forming process environment to the external environment;

[0009] The second-side coating group includes: a second inlet chamber group for realizing the transition from the external environment to the film-making process environment, an RPD coating chamber and a second PVD magnetron sputtering chamber arranged in sequence and used to prepare the TCO thin film on the second side of the battery cell, and a second outlet chamber group for realizing the transition from the film-making process environment to the external environment; the RPD coating chamber and the second PVD magnetron sputtering chamber are used to prepare the RPD+PVD composite TCO film on the second side of the battery cell; the composite TCO film is a stacked composite film in which the PVD film is deposited on the side of the RPD film away from the battery cell silicon wafer.

[0010] In addition, the vacuum coating equipment according to the present application may also have the following additional technical features:

[0011] In some embodiments, the first PVD magnetron sputtering chamber is provided with 1-10 pairs of rotating cathodes or planar cathodes, and any cathode is used for coating upward;

[0012] The RPD coating chamber is equipped with 1-8 plasma generating devices, which are arranged in any combination; each plasma generating device is correspondingly provided with a crucible for mounting a target material, and a target material supply structure for automatically supplying the target material is provided below the crucible; the plasma generating device coats upwards;

[0013] The second PVD magnetron sputtering chamber is provided with 1-10 pairs of rotating cathodes or planar cathodes in the chamber, and any cathode is used for coating upward.

[0014] In some embodiments, the first inlet chamber group includes a first inlet lock chamber, a first inlet buffer chamber, and a first inlet transition chamber arranged in sequence; the first outlet chamber group includes a first outlet transition chamber, a first outlet buffer chamber, and a first outlet lock chamber arranged in sequence;

[0015] The second input chamber group includes a second input lock chamber, a second input buffer chamber and a second input transition chamber arranged in sequence; the second output chamber group includes a second output transition chamber, a second output buffer chamber and a second output lock chamber arranged in sequence.

[0016] In some embodiments, the first and second inlet transition chambers are each provided with a first transmission mode changing structure to change the transmission mode of the carrier plate from an intermittent mode to a continuous mode;

[0017] The first and second outlet transition chambers are both provided with a second transmission mode changing structure to change the transmission mode of the carrier plate from a continuous mode to an intermittent mode.

[0018] In some embodiments, gate valve structures are provided at the inlet ends of the first and second inlet lock chambers, between the first inlet lock chamber and the first inlet buffer chamber, between the first inlet buffer chamber and the first inlet transition chamber, between the second inlet lock chamber and the second inlet buffer chamber, and between the second inlet buffer chamber and the second inlet transition chamber; the gate valve structures are connected to the main control unit;

[0019] A gate valve structure is provided between the first outlet transition chamber and the first outlet buffer chamber, between the first outlet buffer chamber and the first outlet lock chamber, between the second outlet transition chamber and the second outlet buffer chamber, between the second outlet buffer chamber and the second outlet lock chamber, and at the outlet ends of the first and second outlet lock chambers; the gate valve structure is connected to the main control unit.

[0020] In some embodiments, the first and second inlet lock chambers, the first and second inlet buffer chambers, the first and second outlet buffer chambers, and the first and second outlet lock chambers are respectively provided with a first vacuum pump group at the chambers, and a first vacuum gauge group is respectively provided in the chambers; the first vacuum pump group is connected to the corresponding chamber; the first vacuum pump group and the first vacuum gauge group are both connected to the main control unit, and the main control unit controls the operation of the first vacuum pump group according to the measurement results of the first vacuum gauge group to achieve vacuuming of the chamber.

[0021] In some embodiments, the vacuum degrees in the chambers of the first input lock chamber, the first input buffer chamber and the first input transition chamber, and the vacuum degrees in the chambers of the second input lock chamber, the second input buffer chamber and the second input transition chamber are all enhanced in sequence; the vacuum degrees in the chambers of the first output transition chamber, the first output buffer chamber and the first output lock chamber, and the vacuum degrees in the chambers of the second output transition chamber, the second output buffer chamber and the second output lock chamber are all weakened in sequence.

[0022] In some embodiments, the first and second inlet buffer chambers are both provided with a heater for heating the carrier and the battery cells and a first thermometer for measuring real-time temperature, the heater and the first thermometer are both connected to the main control unit, and the main control unit controls the operation of the heater according to the measurement results of the first thermometer; and / or

[0023] The first and second output buffer chambers are both provided with a cooler for cooling the carrier and the battery cells and a second thermometer for measuring the real-time temperature. The cooler and the second thermometer are both connected to the main control unit, and the main control unit controls the operation of the cooler according to the measurement results of the second thermometer.

[0024] In some embodiments, the first and second inlet buffer chambers are both provided with a first gas buffer structure, and the first gas buffer structure is provided at the gate valve of the inlet transition chamber;

[0025] The first gas buffer structure is connected to an external compensation gas circuit system and is used to inject gas to reduce the pressure fluctuation of the subsequent process chamber when the gate valve is opened;

[0026] A first gas mass flow meter is provided in the first gas buffer structure for measuring the amount of injected gas;

[0027] The first gas buffer structure and the first gas mass flow meter are both connected to the main control unit, and the main control unit controls the operation of the gas buffer structure according to the amount of gas injected.

[0028] In some embodiments, a second gas buffer structure is further provided in the chamber of the outlet buffer chamber, and the second gas buffer structure is provided near the gate valve of the outlet transition chamber;

[0029] The second gas buffer structure is connected to an external compensation gas circuit system and is used to inject gas to reduce the pressure fluctuation of the subsequent process chamber when the gate valve is opened;

[0030] A second gas mass flow meter is provided in the second gas buffer structure for measuring the amount of injected gas;

[0031] The second gas buffer structure and the second gas mass flow meter are both connected to the main control unit, and the main control unit controls the operation of the second gas buffer structure according to the amount of gas injected.

[0032] In some embodiments, the first inlet transition chamber, the first PVD magnetron sputtering chamber, and the first outlet transition chamber share one or more second vacuum pump groups, one or more second vacuum gauge groups are provided in the chambers, and the second vacuum pump groups are connected to the corresponding chambers; the second inlet transition chamber and the RPD coating chamber, the second PVD magnetron sputtering chamber, and the second outlet transition chamber share one or two third vacuum pump groups, one or two third vacuum gauge groups are provided in the chambers, and the third vacuum pump groups are connected to the corresponding chambers;

[0033] The RPD coating chamber is provided with a fourth vacuum pump group at the chamber, and a fourth vacuum gauge group is provided in the chamber; the fourth vacuum pump group is connected to the corresponding chamber;

[0034] The second vacuum pump group and the second vacuum gauge group, the third vacuum pump group and the third vacuum gauge group, and the fourth vacuum pump group and the fourth vacuum gauge group are all connected to the main control unit. The main control unit controls the corresponding vacuum pump group to operate according to the measurement results of each vacuum gauge group to achieve vacuuming of the chamber.

[0035] In some embodiments, the first PVD magnetron sputtering chamber, the RPD coating chamber, and the second PVD magnetron sputtering chamber are respectively equipped with one or more process gas circuit systems containing gas mass flow meters, the gas outlets of the process gas circuit systems are arranged in the corresponding chambers, and the process gas circuit systems and the gas mass flow meters arranged therein are both connected to the main control unit, and the main control unit issues instructions to control the process gas circuit systems to inject process gas according to the measurement results of the gas mass flow meters;

[0036] A gas isolation chamber is provided between the RPD coating chamber and the second PVD magnetron sputtering chamber.

[0037] An embodiment of the present application also provides a vacuum coating equipment system, which includes the vacuum coating equipment as described above.

[0038] Compared with the prior art, the present invention has at least the following beneficial effects:

[0039] In the embodiment of the present application, the vacuum coating equipment provided adopts a unique method to realize the combination of RPD and PVD to prepare heterojunction solar cells. The TCO film on one side of the cell is deposited by PVD, and the TCO film on the other side is prepared into a composite film by RPD+PVD. This not only improves the energy conversion efficiency of the PVD films on both sides, but also achieves no excessive dependence on the RPD equipment, avoiding the problem of limitation due to the small production capacity of the RPD equipment.

[0040] The vacuum coating system of the present application includes the aforementioned vacuum coating apparatus and thus has at least all the features and advantages of the aforementioned vacuum coating apparatus, which will not be described in detail herein. Additional aspects and advantages of the present application will be described in part in the following description and will become apparent from the following description or learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] FIG1 is a schematic structural diagram of a vacuum coating device disclosed in an embodiment of the present application;

[0042] FIG2 is a schematic structural diagram of a vacuum coating device disclosed in another embodiment of the present application.

[0043] Description of reference numerals:

[0044] C1-inlet lock chamber; C2-inlet buffer chamber; C3-inlet transition chamber; C401-first PVD magnetron sputtering chamber; C402-RPD coating chamber; C403-second PVD magnetron sputtering chamber; C5-exit transition chamber; C6-exit buffer chamber; C7-exit lock chamber. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0046] The embodiments of the present application are described in detail below through specific embodiments and their application scenarios in conjunction with the accompanying drawings.

[0047] As shown in FIG1 , in some embodiments of the present application, a vacuum coating device is provided that can be used in the preparation process of high-efficiency heterojunction solar cells, such as implementing coating treatment on solar cells during the preparation process of heterojunction solar cells. The composite device of RPD and PVD can realize the preparation of RPD+PVD composite film, which has excellent photoelectric properties and can improve the performance of heterojunction solar cells. The composite device can fully utilize the advantages of RPD coating, while using PVD to share some coating steps, avoiding the shortcomings of insufficient production capacity of RPD equipment, reducing dependence on RPD equipment, and at the same time meeting the film quality requirements.

[0048] Specifically, as shown in FIG1 , in one embodiment of the present application, the vacuum coating equipment includes: an automatic film loading mechanism, a first-side coating group, an automatic film turning device, a second-side coating group, and an automatic film unloading mechanism;

[0049] The first-side coating group includes an inlet lock chamber C1, an inlet buffer chamber C2, an inlet transition chamber C3, a first PVD magnetron sputtering chamber C401, an outlet transition chamber C5, an outlet buffer chamber C6 and an outlet lock chamber C7, which are arranged in sequence; the second-side coating group includes an inlet lock chamber C1, an inlet buffer chamber C2, an inlet transition chamber C3, an RPD coating chamber C402, a gas isolation chamber, a second PVD magnetron sputtering chamber C403, an outlet transition chamber C5, an outlet buffer chamber C6 and an outlet lock chamber C7, which are arranged in sequence.

[0050] In the first-side coating group, gate valve structures are provided between the automatic loading mechanism and the connected input lock chamber C1, between the input lock chamber C1 and the input buffer chamber C2, between the input buffer chamber C2 and the input transition chamber C3, between the output transition chamber C5 and the output buffer chamber C6, between the output buffer chamber C6 and the output lock chamber C7, and between the output lock chamber C7 and the automatic film turning device. These gate valve structures are used to open when the previous structure or chamber completes the preparation steps and enters the next chamber to allow the battery cells to pass through, and then close to maintain the isolation between the two chambers.

[0051] In the second-side coating group, gate valve structures are provided between the automatic film turning device and the connected inlet lock chamber C1, between the inlet lock chamber C1 and the inlet buffer chamber C2, between the inlet buffer chamber C2 and the inlet transition chamber C3, between the outlet transition chamber C5 and the outlet buffer chamber C6, between the outlet buffer chamber C6 and the outlet lock chamber C7, and between the outlet lock chamber C7 and the automatic film unloading mechanism. These gate valve structures are used to open to allow the battery cells to pass through when the previous structure or chamber completes the preparation steps and enters the next chamber, and then close to maintain the isolation state between the two chambers.

[0052] In this embodiment, each chamber is equipped with a corresponding transmission structure to enable the carrier plate carrying the battery cells to be transported within each chamber and between chambers, thereby reaching the designated workstation for the implementation of each preparation step. The transmission structure can adopt existing structures in the prior art and is not further limited in this application. The automated loading mechanism also adopts existing structures to automatically load the cells.

[0053] In this embodiment, each of chambers C1-C3, C401-C403, and C5-C7 includes a corresponding chamber (also called an inner cavity) and structures, components, equipment, systems, etc. arranged inside and outside the chamber for realizing the process requirements and / or specific functions of the chamber before, during, and after the TCO film preparation.

[0054] In this embodiment, the inlet and outlet ends of the inlet lock chamber C1 in both the first-side and second-side coating groups are atmospheric and the transitional vacuum state of the inlet buffer chamber C2, respectively. Therefore, the purpose of inlet lock chamber C1 is to achieve a transition between atmospheric and transitional vacuum states, also known as a rough vacuum state. The inlet valve of inlet lock chamber C1 is exposed to the atmosphere. The inlet valve is open (while the outlet valve is closed) to receive a substrate from the automated loading mechanism under atmospheric conditions. The inlet valve is then closed and a vacuum pump is performed, reducing the pressure within the chamber to a rough vacuum state. An independent vacuum pump group is provided at the chamber of the entry lock chamber C1, which is connected to the inner cavity of the entry lock chamber C1. The chamber of the entry lock chamber C1 is vacuumed through the action of the vacuum pump group. A vacuum gauge is also provided in the chamber of the entry lock chamber C1 for real-time measurement of the vacuum degree in the chamber. The vacuum gauge is connected to the main control unit provided outside. The main control unit compares the real-time vacuum degree measured by the vacuum gauge with the preset vacuum threshold, and controls the operation of the vacuum pump group according to the comparison result, and stops vacuuming when the vacuum degree reaches the vacuum threshold.

[0055] In this embodiment, the inlet buffer chamber C2 in both the first-side coating group and the second-side coating group receives carriers from the inlet lock chamber C1, heats the carriers and the silicon wafers thereon, and then transfers the carriers to the next chamber, the inlet transition chamber C3. Accordingly, a heater and a temperature meter are installed within the inlet buffer chamber C2. Both heater and temperature meter are connected to a main control unit, which compares the real-time temperature measured by the temperature meter with a preset temperature threshold. Based on the comparison result, the main control unit controls the operation of the heater and stops heating when the temperature threshold is reached. The inlet and outlet ends of the inlet buffer chamber C2 are the rough vacuum state and the film-forming vacuum state of C3, respectively. Therefore, the inlet buffer chamber C2 is also intended to provide a buffered transition between the rough vacuum state and the film-forming vacuum state. The inlet gate valve of the inlet buffer chamber C2 is connected to the inlet lock chamber C1. The inlet gate valve is opened (the outlet gate valve is closed at this time) to receive the carrier transferred from the inlet lock chamber C1 under the vacuum exchange state of C1 and C2. Then the inlet gate valve is closed and the vacuum operation is performed to reduce the air pressure inside to the film forming vacuum state. The inlet buffer chamber is equipped with an independent vacuum pump group, which is connected to the inner cavity of the inlet buffer chamber C2. The inner cavity of the inlet buffer chamber C2 is vacuumed by the action of the vacuum pump group. A vacuum gauge is also provided in the chamber of the inlet buffer chamber C2 for real-time measurement of the vacuum degree in the chamber. The vacuum gauge is connected to the main control unit located outside. The main control unit compares the real-time vacuum degree measured by the vacuum gauge with the preset vacuum threshold, and controls the operation of the vacuum pump group based on the comparison result, stopping the vacuum when the vacuum degree reaches the vacuum threshold. A gas buffer structure is also installed within the inlet buffer chamber C2. This structure is located at the gate valve of the inlet transition chamber C3 and is connected to the compensation gas system. When the gate valve is opened, the gas buffer structure injects gas to reduce pressure fluctuations in subsequent process chambers. Specifically, before the gate valve between the inlet buffer chamber C2 and the inlet transition chamber C3 is opened, the gas buffer structure begins to introduce gas, bringing the pressure within C2 to the same level as that in the inlet transition chamber C3. This ensures that opening the gate valve does not cause significant pressure fluctuations in the inlet transition chamber C3, the first PVD magnetron sputtering chamber C401, or the RPD coating chamber C402. A gas mass flowmeter is installed within the gas buffer structure to measure the amount of injected gas. Both the gas buffer structure and the gas mass flowmeter are connected to the main control unit, which receives gas levels and controls the operation of the gas buffer structure based on whether the gas levels meet the required standards.

[0056] In this embodiment, the inlet transition chamber C3 in the first-side coating group and the second-side coating group receives the carrier from the inlet buffer chamber C2, switches the carrier's transmission mode from discontinuous mode to continuous mode, and converts the transmission speed to the transmission speed set by the process. The carrier is then transferred to the next chamber for coating, namely, the first PVD magnetron sputtering chamber C401 or the RPD coating chamber C402. The structure for converting from discontinuous mode to continuous mode can adopt existing structures and is not limited in this application. In addition, in order to ensure the vacuum degree in the entry transition chamber C3, an independent vacuum pump group is provided at the entry transition chamber C3 chamber, and the vacuum pump group is connected to the inner cavity of the entry transition chamber C3, and the entry transition chamber C3 is evacuated by the action of the vacuum pump group; a vacuum gauge is also provided in the cavity of the entry transition chamber C3 for real-time measurement of the vacuum degree in the chamber, and the vacuum gauge is connected to the main control unit provided outside, and the main control unit compares the real-time vacuum degree measured by the vacuum gauge with a preset vacuum threshold, and controls the operation of the vacuum pump group according to the comparison result, and stops vacuuming when the vacuum degree reaches the vacuum threshold.

[0057] In one embodiment of the present application, the first PVD magnetron sputtering chamber C401 in the first-side coating group is equipped with 1-10 pairs of rotating cathodes or planar cathode devices. Any cathode can achieve upward coating, which is used to deposit the first TCO film on the first side of the incoming solar cell. In this solution, the p-side of the solar cell (the side with the p-type microcrystalline silicon layer) is transmitted downward into the first-side coating group, so the first side of the solar cell can be the p-side of the solar cell. The first PVD magnetron sputtering chamber C401 is equipped with a process gas circuit system containing a gas mass flowmeter. The gas outlet of the process gas circuit system is located in the chamber, and the process gas circuit system and the gas mass flowmeter therein are both connected to the main control unit for injecting process gas according to the instructions of the main control unit to ensure that the gas environment in the sputtering chamber meets the requirements of thin film deposition. In addition, in order to ensure that the vacuum degree in the first PVD magnetron sputtering chamber C401 is suitable for thin film preparation, an independent vacuum pump group is provided in the first PVD magnetron sputtering chamber C401, and the vacuum pump group is connected to the inner cavity of the first PVD magnetron sputtering chamber C401. The first PVD magnetron sputtering chamber C401 is vacuumed by the action of the vacuum pump group; a vacuum gauge is also provided in the chamber of the first PVD magnetron sputtering chamber C401 for real-time measurement of the vacuum degree in the chamber. The vacuum gauge is connected to a main control unit provided outside. The main control unit compares the real-time vacuum degree measured by the vacuum gauge with a preset vacuum threshold, and controls the operation of the vacuum pump group according to the comparison result, and stops vacuuming when the vacuum degree reaches the vacuum threshold.

[0058] In another embodiment, the first PVD magnetron sputtering chamber C401 is equipped with a multi-channel process gas system including a gas mass flow meter. The gas outlets of the multi-channel process gas system are located at various locations within the first PVD magnetron sputtering chamber C401 to facilitate gas injection and ensure gas uniformity.

[0059] In another embodiment, there are multiple vacuum gauges in the first PVD magnetron sputtering chamber C401, that is, a vacuum gauge group. The vacuum gauges in the vacuum gauge group are arranged at various positions in the first PVD magnetron sputtering chamber C401 to collect the vacuum degree at various locations. When leakage or defects occur, the fault location can be measured more quickly and sensitively, thereby further ensuring the quality of thin film sputtering deposition.

[0060] In one embodiment of the present application, the RPD coating chamber C402 in the second-side coating group receives a substrate transferred from the inlet transition chamber C3 and performs dynamic reactive ion plating according to the process settings. After coating, the substrate is transferred to the next chamber, the second PVD magnetron sputtering chamber C403. This RPD chamber is equipped with one to eight plasma generators, which are arranged in any combination within the chamber. Each plasma generator is equipped with a corresponding crucible for mounting a target material, and a target supply structure is installed below the crucible for automatic target material supply. This chamber can only coat upward, used to form the second TCO film on the second side (n-side) of the cell. In this solution, after the first side coating is completed on the p-side of the cell, the cell is flipped over, and the n-side (the side with the n-type microcrystalline silicon layer) is transferred downward to the second-side coating group. Therefore, the second side of the cell becomes the n-side of the cell. The RPD coating chamber C402 is equipped with a process gas system containing a gas mass flow meter. The gas outlet of the process gas system is located in the chamber, and the process gas system and the gas mass flow meter therein are connected to the main control unit for injecting process gas according to the instructions of the main control unit to ensure that the gas environment in the RPD coating chamber meets the requirements of thin film deposition. In addition, in order to ensure that the vacuum degree in the RPD coating chamber C402 is suitable for thin film preparation, an independent vacuum pump group is provided in the RPD coating chamber C402, and the vacuum pump group is connected to the inner cavity of the RPD coating chamber C402. The RPD coating chamber C402 is vacuumed by the action of the vacuum pump group; a vacuum gauge is also provided in the RPD coating chamber C402 for real-time measurement of the vacuum degree in the chamber. The vacuum gauge is connected to an external main control unit. The main control unit compares the real-time vacuum degree measured by the vacuum gauge with a preset vacuum threshold, and controls the operation of the vacuum pump group according to the comparison result, and stops vacuuming when the vacuum degree reaches the vacuum threshold.

[0061] In another embodiment, the RPD coating chamber C402 is equipped with a multi-channel process gas system including a gas mass flow meter. The gas outlets of the multi-channel process gas system are located at various locations within the RPD coating chamber C402 to better inject gas and ensure gas uniformity.

[0062] In another embodiment, there are multiple vacuum gauges in the RPD coating chamber C402, that is, a vacuum gauge group. The vacuum gauges in the vacuum gauge group are arranged at various positions in the RPD coating chamber C402 to collect the vacuum degree at various locations. When leakage or defects occur, the fault location can be measured more quickly and sensitively, thereby further ensuring the quality of thin film deposition.

[0063] In this embodiment, the second PVD magnetron sputtering chamber C403 is equipped with 1-10 pairs of rotating or flat cathodes. Any of these cathodes can be used for coating with the film facing upwards, collaborating with the RPD chamber to deposit the transparent conductive film on the back side of the battery. The second PVD magnetron sputtering chamber C403 is used to sputter a third TCO film onto the outer surface of the second TCO film (i.e., the side facing away from the silicon wafer). The second and third TCO films together form an RPD+PVD composite film, which serves as the TCO film on the back side of the battery, also known as the transparent conductive film. The second PVD magnetron sputtering chamber C403 is equipped with a process gas flow system containing a gas mass flowmeter. The outlet of this process gas flow system is located within the chamber. The process gas flow system and its gas mass flowmeter are connected to the main control unit, which controls the injection of process gas according to the main control unit's instructions to ensure that the gas environment within the PVD magnetron sputtering chamber meets the requirements for thin film sputtering deposition. In addition, in order to ensure that the vacuum degree in the second PVD magnetron sputtering chamber C403 is suitable for thin film preparation, an independent vacuum pump group is provided at the second PVD magnetron sputtering chamber C403, and the vacuum pump group is connected to the inner cavity of the second PVD magnetron sputtering chamber C403. The second PVD magnetron sputtering chamber C403 is evacuated by the action of the vacuum pump group; a vacuum gauge is also provided in the chamber of the second PVD magnetron sputtering chamber C403 for real-time measurement of the vacuum degree in the chamber. The vacuum gauge is connected to a main control unit provided outside. The main control unit compares the real-time vacuum degree measured by the vacuum gauge with a preset vacuum threshold, and controls the operation of the vacuum pump group according to the comparison result, and stops vacuuming when the vacuum degree reaches the vacuum threshold.

[0064] In another embodiment, the second PVD magnetron sputtering chamber C403 is equipped with a multi-channel process gas system including a gas mass flow meter. The gas outlets of the multi-channel process gas system are located at various locations within the second PVD magnetron sputtering chamber C403 to facilitate gas injection and ensure gas uniformity.

[0065] In another embodiment, there are multiple vacuum gauges in the second PVD magnetron sputtering chamber C403, that is, a vacuum gauge group. The vacuum gauges in the vacuum gauge group are arranged at various positions in the second PVD magnetron sputtering chamber C403 to collect the vacuum degree at various locations. When leakage or defects occur, the fault location can be measured more quickly and sensitively, thereby further ensuring the quality of thin film deposition.

[0066] As a preferred embodiment, a gas isolation chamber is provided between the RPD coating chamber C402 and the second PVD magnetron sputtering chamber C403 in the second-side coating group. The gas isolation chamber is used to isolate the gases between the RPD coating chamber C402 and the second PVD magnetron sputtering chamber C403, preventing the gases in the two adjacent process chambers from intermingling. This ensures the independence of the film-forming environments of the RPD coating chamber C402 and the second PVD magnetron sputtering chamber C403. This allows the adjacent process chambers to select significantly different process parameters during film coating. The device for achieving gas isolation is generally a high-speed molecular pump set.

[0067] In one embodiment of the present application, the outlet transition chamber C5, outlet buffer chamber C6, and outlet lock chamber C7 in the first-side coating group and the second-side coating group are arranged in one-to-one correspondence with the inlet transition chamber C3, inlet buffer chamber C2, and inlet lock chamber C1 of the inlet end of the coating group, wherein:

[0068] The exit transition chamber C5 is used to switch the transport mode of the carriers transferred from the preceding process vacuum chamber from continuous to discontinuous mode, and to convert the transport speed to the process-set transmission speed before transmitting them to the subsequent exit chamber and the film turning or unloading mechanism. The exit transition chamber C5 is equipped with an independent vacuum pump and vacuum gauge to ensure that the vacuum level within the exit transition chamber C5 meets the specified requirements after the gate valve is opened and closed.

[0069] As a preferred embodiment, since the three chambers of the inlet transition chamber C3, the first PVD magnetron sputtering chamber C401, and the outlet transition chamber C5 are sequentially connected, the three chambers can share a vacuum pump group and a vacuum gauge group. The vacuum pumping positions and the vacuum gauges are evenly located in the three chambers to ensure the consistency of the air pressure changes in each chamber during the vacuum pumping process. Similarly, the inlet transition chamber C3 and the RPD coating chamber C402, as well as the second PVD magnetron sputtering chamber C403 and the outlet transition chamber C5, are also connected to each other. The two chambers can share a vacuum pump group and a vacuum gauge group. The vacuum pumping positions and the vacuum gauges are evenly located in the two chambers to ensure the consistency of the air pressure changes in each chamber during the vacuum pumping process.

[0070] The outlet buffer chamber C6 is used to cool the carrier and battery cells transferred from the outlet transition chamber C5, and to transfer the carrier to the next chamber. Like the inlet buffer chamber C2, the outlet buffer chamber C6 is equipped with an independent vacuum pump group and vacuum gauge group to ensure that the vacuum level in the outlet buffer chamber meets the predetermined requirements after the gate valve is opened and closed. It is also equipped with a gas buffer structure. The gas buffer structure is located near the gate valve of the outlet transition chamber C5. The gas buffer structure is connected to the compensation gas gas path system. Before the gate valve is opened, gas is injected by the gas buffer structure to reduce the pressure fluctuation of the subsequent process chamber when the gate valve is opened. A gas mass flowmeter is provided in the gas buffer structure to measure the amount of gas injected. The gas buffer structure and the gas mass flowmeter are both connected to the main control unit. The main control unit receives the gas volume and controls the operation of the gas buffer structure according to whether the gas volume meets the standard to reduce the pressure fluctuation of the process chamber when the gate valve is opened.

[0071] Optionally, cooling of the carrier board and the battery cells is achieved by installing a corresponding cooling device in the chamber. The cooling device can be a water cooling device or a temperature control system using other refrigerants to set the chamber ambient temperature.

[0072] The exit lock chamber C7 receives carriers from the exit buffer chamber C6, returns the vacuum chamber to atmospheric pressure, and delivers the carriers to the automated lift platform. Like the inlet lock chamber C1, the exit lock chamber C7 is equipped with an independent vacuum pump and vacuum gauge assembly, which evacuates the chamber after the gate valve is opened and closed, ensuring a rough vacuum.

[0073] In one embodiment of the present application, the automatic flipping device is located in an atmospheric pressure environment and is used to flip the cell placed on the carrier board and then place the flipped cell back on the carrier board for entry into the second-side coating group for second-side coating. Automatic flipping devices are already available in the prior art, and this application does not impose excessive restrictions on the specific structure of the automatic flipping device. It is sufficient that it can achieve the flipping function required by this application.

[0074] Optionally, in the present application, the order of front-side coating and back-side coating of the battery cell can be adjusted, that is, the setting order of the first-side coating group and the second-side coating group can be adjusted. For example, as shown in Figure 2, the second-side coating group is set in front of the first-side coating group, and the two ends of the second-side coating group are respectively connected to the automatic loading mechanism and the automatic flipping device, and the two ends of the first-side coating group are respectively connected to the automatic flipping device and the automatic unloading mechanism; the setting method of each chamber inside the first-side coating group and the second-side coating group remains unchanged.

[0075] Optionally, some or all of the inlet buffer chamber C2, inlet transition chamber C3, first PVD magnetron sputtering chamber C401, RPD coating chamber C402, second PVD magnetron sputtering chamber C403, and outlet transition chamber C5 in the first-side coating group and the second-side coating group of the present application may be configured with variable temperature cold traps to control the water vapor content within the chambers. The implementation of the variable temperature cold traps is not specifically limited in this application; existing technologies may be employed.

[0076] Table 1 below shows the performance data of TCO films of different thicknesses prepared by PVD, RPD, and RPD+PVD, including mobility and transmittance.

[0077] Table 1

[0078]

[0079] As shown in Table 1, RPD coating has great advantages in terms of material mobility and transmittance. However, the equipment cost of RPD is high and the equipment production capacity is not high. If the RPD+PVD coating method is used, only 1 / 8 (or more) of the total thickness of the RPD film is required, and the performance of the film prepared entirely with RPD can be the same as or even better.

[0080] It should be pointed out that in the prior art, there is a solution: TCO film is deposited on one side of the battery by RPD, and TCO film is deposited on the other side by PVD+RPD; this preparation method solves its specific technical problems, but since RPD equipment is required for deposition on both sides, and one side is used alone, there is a large demand for the use of RPD equipment, and it is limited by the production capacity of RPD equipment. The technical problems recorded in the background technology of this application will still exist, that is, it cannot solve the technical problems of this application.

[0081] The parts of the present invention that are not described in detail are well known to those skilled in the art.

[0082] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

Claims

1. A vacuum coating device, characterized in that: The device comprises a first-side coating group, an automatic film turning device, a second-side coating group and a main control unit; the first-side coating group, the automatic film turning device and the second-side coating group are all connected to the main control unit and work under the control of the main control unit; The first-side coating group includes: a first inlet chamber group for realizing the transition from the external environment to the film-making process environment, a first PVD magnetron sputtering chamber for preparing a TCO film on the first side of the cell, and a first outlet chamber group for realizing the transition from the film-making process environment to the external environment; The second-side coating group includes: a second inlet chamber group for realizing the transition from the external environment to the film-making process environment, an RPD coating chamber and a second PVD magnetron sputtering chamber which are arranged in sequence and used to prepare TCO thin film on the second side of the battery cell, and a second outlet chamber group for realizing the transition from the film-making process environment to the external environment; the RPD coating chamber and the second PVD magnetron sputtering chamber are used to prepare an RPD+PVD composite TCO film on the second side of the battery cell; the composite TCO film is a stacked composite film in which a PVD film is deposited on the side of the RPD film away from the battery cell silicon wafer.

2. The vacuum coating equipment according to claim 1, characterized in that: The first PVD magnetron sputtering chamber is provided with 1-10 pairs of rotating cathodes or planar cathodes, and any cathode is used for coating upwards; The RPD coating chamber is equipped with 1-8 plasma generating devices in the chamber, and the plasma generating devices are arranged in any combination; each of the plasma generating devices is correspondingly provided with a crucible for mounting a target material, and a target material supply structure for automatically supplying the target material is provided under the crucible; the plasma generating device coats upwards; The second PVD magnetron sputtering chamber is provided with 1-10 pairs of rotating cathodes or planar cathodes in the chamber, and any cathode is used for coating upward.

3. The vacuum coating equipment according to claim 1, characterized in that: The first inlet chamber group includes a first inlet lock chamber, a first inlet buffer chamber and a first inlet transition chamber arranged in sequence; the first outlet chamber group includes a first outlet transition chamber, a first outlet buffer chamber and a first outlet lock chamber arranged in sequence; The second inlet chamber group includes a second inlet lock chamber, a second inlet buffer chamber and a second inlet transition chamber which are arranged in sequence; the second outlet chamber group includes a second outlet transition chamber, a second outlet buffer chamber and a second outlet lock chamber which are arranged in sequence.

4. The vacuum coating equipment according to claim 3, characterized in that: The first and second inlet transition chambers are both provided with a first transmission mode changing structure to change the transmission mode of the carrier plate from an intermittent mode to a continuous mode; The chambers of the first and second outlet transition chambers are both provided with a second transmission mode changing structure to change the transmission mode of the carrier plate from a continuous mode to an intermittent mode.

5. The vacuum coating equipment according to claim 3, characterized in that: Gate valve structures are provided at the inlet ends of the first and second inlet lock chambers, between the first inlet lock chamber and the first inlet buffer chamber, between the first inlet buffer chamber and the first inlet transition chamber, between the second inlet lock chamber and the second inlet buffer chamber, and between the second inlet buffer chamber and the second inlet transition chamber; the gate valve structures are connected to the main control unit; A gate valve structure is provided between the first outlet transition chamber and the first outlet buffer chamber, between the first outlet buffer chamber and the first outlet lock chamber, between the second outlet transition chamber and the second outlet buffer chamber, between the second outlet buffer chamber and the second outlet lock chamber, and at the outlet ends of the first and second outlet lock chambers; the gate valve structure is connected to the main control unit.

6. The vacuum coating equipment according to claim 3, characterized in that: The first and second inlet lock chambers, the first and second inlet buffer chambers, the first and second outlet buffer chambers, and the first and second outlet lock chambers are respectively provided with a first vacuum pump group at their chambers, and the chambers are respectively provided with a first vacuum gauge group; the first vacuum pump group is connected to the corresponding chamber; the first vacuum pump group and the first vacuum gauge group are both connected to the main control unit, and the main control unit controls the first vacuum pump group to operate according to the measurement results of the first vacuum gauge group to achieve vacuuming of the chamber.

7. The vacuum coating equipment according to claim 3, characterized in that: The vacuum degree in the chambers of the first input end lock chamber, the first input end buffer chamber and the first input end transition chamber, as well as the vacuum degree in the chambers of the second input end lock chamber, the second input end buffer chamber and the second input end transition chamber are all increased in sequence; the vacuum degree in the chambers of the first output end transition chamber, the first output end buffer chamber and the first output end lock chamber, as well as the vacuum degree in the chambers of the second output end transition chamber, the second output end buffer chamber and the second output end lock chamber are all weakened in sequence.

8. The vacuum coating equipment according to claim 3, characterized in that: The first and second inlet buffer chambers are both provided with a heater for heating the carrier and the battery cell and a first thermometer for measuring the real-time temperature, the heater and the first thermometer are both connected to the main control unit, and the main control unit controls the heater to work according to the measurement result of the first thermometer; and / or, The first and second output buffer chambers are both provided with a cooler for cooling the carrier and the battery cells and a second thermometer for measuring the real-time temperature. The cooler and the second thermometer are both connected to the main control unit, and the main control unit controls the operation of the cooler according to the measurement results of the second thermometer.

9. The vacuum coating equipment according to claim 3, characterized in that: The first and second inlet buffer chambers are both provided with a first gas buffer structure, and the first gas buffer structure is arranged at the gate valve of the inlet transition chamber; The first gas buffer structure is connected to an external compensation gas gas circuit system and is used to inject gas to reduce the fluctuation of the pressure of the subsequent process chamber when the gate valve is opened; A first gas mass flow meter is provided in the first gas buffer structure for measuring the amount of injected gas; The first gas buffer structure and the first gas mass flow meter are both connected to the main control unit, and the main control unit controls the operation of the gas buffer structure according to the amount of gas injected.

10. The vacuum coating equipment according to claim 3, characterized in that: A second gas buffer structure is also provided in the chamber of the outlet buffer chamber, and the second gas buffer structure is provided near the gate valve of the outlet transition chamber; The second gas buffer structure is connected to an external compensation gas gas circuit system and is used to inject gas to reduce the fluctuation of the pressure of the subsequent process chamber when the gate valve is opened; A second gas mass flow meter is provided in the second gas buffer structure for measuring the amount of injected gas; The second gas buffer structure and the second gas mass flow meter are both connected to the main control unit, and the main control unit controls the operation of the second gas buffer structure according to the amount of gas injected.

11. The vacuum coating equipment according to claim 3, characterized in that: The first entry transition chamber, the first PVD magnetron sputtering chamber and the first exit transition chamber share one or more second vacuum pump groups, one or more second vacuum gauge groups are provided in the chambers, and the second vacuum pump groups are connected to the corresponding chambers; the second entry transition chamber and the RPD coating chamber, the second PVD magnetron sputtering chamber and the second exit transition chamber share one or two third vacuum pump groups, one or two third vacuum gauge groups are provided in the chambers, and the third vacuum pump groups are connected to the corresponding chambers; The RPD coating chamber is provided with a fourth vacuum pump set at the chamber, and a fourth vacuum gauge set is provided in the chamber; the fourth vacuum pump set is connected to the corresponding chamber; The second vacuum pump group and the second vacuum gauge group, the third vacuum pump group and the third vacuum gauge group, and the fourth vacuum pump group and the fourth vacuum gauge group are all connected to the main control unit, and the main control unit controls the corresponding vacuum pump group to operate according to the measurement results of each vacuum gauge group to achieve vacuuming of the chamber.

12. The vacuum coating equipment according to claim 1, characterized in that: The first PVD magnetron sputtering chamber, the RPD coating chamber, and the second PVD magnetron sputtering chamber are respectively equipped with one or more process gas circuit systems containing gas mass flow meters, the gas outlets of the process gas circuit systems are arranged in the corresponding chambers, and the process gas circuit systems and the gas mass flow meters arranged therein are connected to the main control unit, and the main control unit issues instructions to control the process gas circuit system to inject process gas according to the measurement results of the gas mass flow meters; A gas isolation chamber is provided between the RPD coating chamber and the second PVD magnetron sputtering chamber.

13. A vacuum coating system, characterized in that: It comprises the vacuum coating equipment as claimed in any one of claims 1 to 12.

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