Hot filament CVD photovoltaic cell edge passivation apparatus and its cavity

Abstract

This invention relates to a cavity for a hot-filament CVD photovoltaic cell edge passivation device, which is a rectangular vacuum cavity including a first dimension x, a second dimension y, and a third dimension z along the length, width, and height directions. At least two carrier channels are arranged in parallel on the end wall along the length direction. Each carrier channel has a fourth dimension b and a fifth dimension h along the width and height directions, and a flap valve sealing assembly is provided at each carrier channel. A molecular pump interface is provided on at least one of the front wall, the rear wall, and the lower wall along the height direction, for connecting a molecular pump. The dimensions are: 1.0m ≤ x ≤ 3.0m, 0.6m ≤ y ≤ 1.2m, 0.8m ≤ z ≤ 3.0m; 0.1m ≤ b ≤ 0.3m, 0.32m ≤ h ≤ 2.0m. This invention achieves optimal adaptation between the parallel and stable transport of multiple carriers and the cavity space and process vacuum environment, improving production capacity and saving costs.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic cell manufacturing equipment technology, and more specifically, to a cavity of a hot-wire chemical vapor deposition (hot-wire CVD) photovoltaic cell edge passivation apparatus and an apparatus containing the cavity. Background Technology

[0002] As the core component of solar photovoltaic power generation, the conversion efficiency and lifespan of photovoltaic cells are directly affected by the passivation effect of the cell surface and edges. During the processing of crystalline silicon photovoltaic cells, a large number of dangling bonds and recombination centers are easily formed in the edge region, leading to carrier recombination and reducing the cell's open-circuit voltage and fill factor. Hot-wire chemical vapor deposition (hot-wire CVD) has become one of the mainstream technologies for photovoltaic cell edge passivation due to its low deposition temperature, good passivation effect, and controllable equipment cost. Its core principle is to rely on a vacuum chamber to complete the decomposition of reactive gases and the deposition of passivation film. Existing hot-wire CVD photovoltaic cell edge passivation equipment is still focused on improving passivation performance, expanding production capacity, and increasing production efficiency in industrial applications, thereby meeting the industrial production needs of efficient, continuous, and highly consistent photovoltaic cell edge passivation.

[0003] Currently reported hot-wire CVD equipment is classified into two types based on its chamber structure: vertical and horizontal. The hot-wire CVD photovoltaic cell edge passivation equipment currently used for large-scale applications employs a vertical chamber structure, where the carrier plate supporting the silicon wafer moves vertically within the chamber. Chambers are typically connected and isolated using flap valves. To increase production capacity to meet the demands of large-scale manufacturing, the main improvement direction is to directly enlarge the geometry of the chamber. However, this simple scaling-up approach has gradually revealed bottlenecks in engineering practice. Specifically, as the volume of the vertical stainless steel chamber increases, the design requirements for its structural rigidity and sealing increase exponentially. Large-sized chambers are prone to deformation under atmospheric pressure, leading to increased difficulty in vacuum sealing. Maintaining high levels of ultimate vacuum and pumping speed is challenging, directly affecting the density and uniformity of the passivation film. Meanwhile, in order to achieve continuous production, flap valves are often used to connect and isolate large-sized cavities. However, as the valve diameter increases with the size of the equipment, the problem of uneven mechanical load and sealing pressure distribution of the valve plate becomes prominent. Long-term operation can easily lead to valve plate deformation or sealing strip wear, increasing the failure rate and maintenance frequency.

[0004] Therefore, developing a hot-wire CVD photovoltaic cell edge passivation equipment and cavity structure with optimized structure, standardized size, reliable vacuum performance, high production capacity, and easy operation and maintenance, in order to break through the production capacity bottleneck while maintaining or even improving passivation performance and process consistency, has become an urgent technical problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to overcome the capacity bottleneck of existing hot-wire CVD photovoltaic cell edge passivation equipment and its cavity structure while maintaining excellent passivation performance and process consistency. It provides a structurally optimized and dimensionally standardized hot-wire CVD photovoltaic cell edge passivation equipment and its cavity structure. This is achieved by designing a cuboid vacuum cavity with a standardized size range, setting at least two parallel carrier channels and matching flap valve sealing components, optimizing the layout of the molecular pump interface, and enabling simultaneous transport and processing of at least two carriers to improve capacity and ensure the stability and sealing reliability of the cavity vacuum environment. Simultaneously, the layout of the loading area, process area, and unloading area of ​​the entire machine is optimized, and an empty material box return conveyor line is set up, along with a maintenance platform. The proportional relationship between the carrier channel and cavity dimensions is standardized, improving the efficiency of equipment process integration and ease of operation and maintenance. It is compatible with multi-layer stacked material boxes and multi-specification silicon wafers, ensuring the uniformity and consistency of the photovoltaic cell edge passivation film layer, thereby meeting the needs of efficient, continuous, and highly reliable industrial-scale photovoltaic cell edge passivation production.

[0006] To solve the above-mentioned technical problems or achieve the above-mentioned objectives, the present invention adopts the following technical solution: According to one aspect of the present invention, a cavity for a hot-filament CVD photovoltaic cell edge passivation device is provided. The cavity is a cuboid vacuum cavity, including a first dimension x along the length direction, a second dimension y along the width direction, and a third dimension z along the height direction. The cavity has at least two carrier channels arranged in parallel on the end wall along the length direction for at least two carrier plates to pass through. Each carrier channel has a fourth dimension b along the width direction and a fifth dimension h along the height direction. Each carrier channel is provided with a flap valve sealing assembly, which is used to control the opening and closing and sealing of the carrier channel to ensure the vacuum environment of the cavity. The cavity is provided with a molecular pump interface on at least one of the front wall along the width direction, the rear wall along the width direction, and the lower wall along the height direction. The molecular pump interface is used to connect a molecular pump to extract gas from the cavity to maintain a vacuum environment. Among them, 1.0m≤x≤3.0m, 0.6m≤y≤1.2m, 0.8m≤z≤3.0m; 0.1m≤b≤0.3m, 0.32m≤h≤2.0m.

[0007] In one embodiment of the present invention, the fourth dimension b and the second dimension y satisfy a proportional relationship: b=ky, wherein the proportionality coefficient k ranges from 0.083 to 0.5.

[0008] In one embodiment of the present invention, the diameter of the molecular pump interface is selected from any one of 0.16m, 0.2m, 0.25m, 0.32m or 0.4m.

[0009] In one embodiment of the present invention, the first dimension x = 2m, the second dimension y = 0.85m, the third dimension z = 1.25m, the fourth dimension b = 0.15m, and the fifth dimension h = 0.57m.

[0010] In one embodiment of the present invention, at least two carrier channels are used, and at least two molecular pump interfaces are used.

[0011] According to another aspect of the present invention, a hot-filament CVD photovoltaic cell edge passivation apparatus is provided, comprising: Material loading area; The process area is connected to the material loading area; and The material unloading area is connected to the process area. The process area, from top to bottom along the height direction, includes: The cavity as described above; A vacuum system, connected to the cavity, is used to provide and maintain a vacuum environment for the cavity; The empty material box return conveyor line returns empty material boxes from the unloading area to the loading area.

[0012] In one embodiment of the present invention, the cavity includes a feed cavity, at least one process cavity, and a discharge cavity connected in sequence by sealing. The feed cavity, at least one process cavity, and discharge cavity all adopt the cavity structure described above. The feed cavity buffers a carrier plate carrying an uncoated silicon wafer cassette transported from the front-end conveying system and heats the carrier plate before conveying it into the process cavity. The process cavity deposits a passivation film layer on the silicon wafer. The discharge cavity anneals the coated silicon wafer and outputs the carrier plate.

[0013] In one embodiment of the present invention, at least one process cavity includes a first process cavity and a second process cavity, wherein the first process cavity and the second process cavity respectively deposit passivation film layers of different materials on the silicon wafer.

[0014] In one embodiment of the present invention, the cavity in the process area is configured to simultaneously accommodate and process two carrier plates, each carrier plate being constructed to carry multiple material boxes in the length direction and the material boxes being stackable in multiple layers in the height direction, and the coating working surfaces of the two carrier plates are arranged opposite to each other in the cavity.

[0015] In one embodiment of the present invention, the process area is provided with maintenance platforms and basic equipment located below the maintenance platforms on both sides along the width direction. The maintenance platforms are positioned at the height of the cavity and perform maintenance operations on the cavity.

[0016] The technical solution provided by this invention has the following advantages compared with the prior art: This invention achieves standardized cavity structure design by limiting the length, width, and height of the cavity, as well as the width and height of the carrier channel, to a defined dimensional range and proportional relationship. This not only improves the consistency of cavity processing and assembly across different batches but also makes it easy to adapt and integrate into different production lines, reducing manufacturing and maintenance costs.

[0017] This invention features multiple carrier channels arranged in parallel on the end wall of the cavity, equipped with independent flap valve sealing assemblies, supporting the simultaneous and independent entry and exit of multiple carriers into and out of the cavity. This design significantly increases the silicon wafer throughput per unit time, and the channel dimensions are optimized to avoid carrier jamming; the flap valves ensure vacuum sealing of the channels when closed, effectively reducing the risk of leakage and maintaining a stable process environment; the multi-carrier design can achieve a multiple increase in production capacity.

[0018] This invention allows the molecular pump interface to be located on at least one of the front, rear, and lower walls of the cavity, which facilitates the formation of a reasonable gas flow field and enables rapid and uniform pumping. This significantly shortens the time required for vacuuming, improves the stability and control precision of the vacuum level, and thus provides a reliable process basis for the uniform deposition of the edge passivation film.

[0019] The invention features a continuous layout of the loading area, processing area, and unloading area, and integrates an empty material box return conveyor line, making the material flow path simple and smooth. This design reduces manual intervention and material turnover time, supports continuous and automated operation of the production line, and improves the overall equipment utilization rate and capacity.

[0020] The equipment of the present invention has maintenance platforms on both sides of the process area that are matched with the height of the cavity, which facilitates personnel to carry out daily inspections, component replacements and system debugging, significantly improving the maintainability and ease of operation of the equipment and reducing downtime.

[0021] The cavity structure of this invention can support, for example, a dual-carrier arrangement, multi-layer cartridge stacking, and multiple cavities can be flexibly connected in series to form a multi-process continuous processing system. This design enables the equipment to adapt to the edge passivation requirements of silicon wafers of different sizes, and allows for more complex process integration through modular expansion, enhancing the equipment's industrial adaptability and future development potential.

[0022] This invention has systematically optimized the cavity structure, sealing design, air extraction layout, overall integration, and ease of operation and maintenance. Ultimately, while improving the production efficiency of photovoltaic cell edge passivation, it ensures the uniformity and stability of the passivation film quality, thereby helping to improve the photoelectric conversion efficiency and long-term reliability of the cell. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0024] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0025] Figure 1 This diagram illustrates the structure of a cavity in a hot-filament CVD photovoltaic cell edge passivation device according to one embodiment of the present invention. Figure 2 A type of containing Figure 1 A schematic diagram of the structure of a hot-wire CVD photovoltaic cell edge passivation device in a cavity; Figure 3 It shows Figure 2 A schematic diagram of the process area in the equipment.

[0026] The components are as follows: 1. Feeding area; 2. Processing area; 3. Unloading area; 4. Cavity; 41. Feeding chamber; 42. First process chamber; 43. Second process chamber; 44. Discharge chamber; 5. Vacuum system; 6. Empty material box return conveyor line; 7. Carrier plate channel; 8. Carrier plate; 9. Molecular pump interface; 10. Lower wall; 11. End wall. Detailed Implementation

[0027] To better understand the above-described objectives, features, and advantages of this disclosure, embodiments of this disclosure will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0028] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways than those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0029] like Figure 1As shown, in one embodiment of the present invention, a cavity 4 of a hot-filament CVD photovoltaic cell edge passivation device is provided. In this structure, the cavity 4 is a cuboid vacuum cavity, including a first dimension x along the length direction, a second dimension y along the width direction, and a third dimension z along the height direction. At least two carrier channels 7 for at least two carrier plates to pass through are arranged in parallel on the end wall 11 along the length direction of the cavity 4. Each carrier channel 7 has a fourth dimension b along the width direction and a fifth dimension h along the height direction. A flap valve sealing assembly (not shown in the figure) is provided at each carrier channel 7. The component is used to control the opening and closing and sealing of the carrier plate channel 7 to ensure the vacuum environment of the cavity; the cavity 4 is provided with two molecular pump interfaces 9 on the lower wall 10 along the height direction. The molecular pump interfaces 9 are used to connect molecular pumps to extract gas in the cavity 4 to maintain the vacuum environment; wherein, the value range of the first dimension x is 1.0m≤x≤3.0m, the value range of the second dimension y is 0.6m≤y≤1.2m, the value range of the third dimension z is 0.8m≤z≤3.0m, the value range of the fourth dimension b is 0.1m≤b≤0.3m, and the value range of the fifth dimension h is 0.32m≤h≤2.0m.

[0030] This invention achieves standardized cavity structure design by limiting the length, width, and height of the cavity, as well as the width and height of the carrier channels, to a defined dimensional range and proportional relationship. This not only improves the consistency of cavity processing and assembly across different batches but also facilitates adaptation and integration into different production lines, reducing manufacturing and maintenance costs. This invention features multiple carrier channels arranged in parallel on the cavity endwalls, equipped with independent flap valve sealing assemblies, supporting the simultaneous and independent entry and exit of multiple carriers into and out of the cavity. This design significantly increases the silicon wafer throughput per unit time, and the optimized channel dimensions prevent carrier jamming; the flap valves ensure vacuum sealing when the channels are closed, effectively reducing leakage risks and maintaining a stable process environment; the multi-carrier design can achieve a significant increase in production capacity. In the preferred embodiment of this invention, the molecular pump interface is located on the lower wall of the cavity, which facilitates the formation of a reasonable gas flow field, enabling rapid and uniform evacuation. This significantly shortens the time required for vacuuming, improves the stability and control accuracy of the vacuum level, thereby providing a reliable process basis for the uniform deposition of the edge passivation film.

[0031] Of course, in the above embodiments, it is a preferred example to locate the molecular pump interface on the lower wall of the cavity. Alternatively, the molecular pump interface can also be located on the front and rear walls of the cavity, that is, it can be located on at least one of the front, rear, and lower walls of the cavity. Furthermore, the number of molecular pump interfaces is preferably two, but alternatively, more than two molecular pump interfaces can be provided.

[0032] In the above embodiments, such as Figure 1As shown, the fourth dimension b and the second dimension y satisfy the proportional relationship: b=ky, where the proportionality coefficient k ranges from 0.083 to 0.5.

[0033] In the above embodiments, such as Figure 1 As shown, the diameter of the molecular pump interface 9 is selected from any one of 0.16m, 0.2m, 0.25m, 0.32m, or 0.4m. Of course, alternatively, the diameter of the molecular pump interface 9 can also be selected from other suitable sizes.

[0034] In the above embodiments, such as Figure 1 As shown, preferably, the first dimension x = 2m, the second dimension y = 0.85m, the third dimension z = 1.25m, the fourth dimension b = 0.15m, and the fifth dimension h = 0.57m. The specific values ​​of the first dimension x, the second dimension y, the third dimension z, the fourth dimension b, and the fifth dimension h are merely preferred examples; alternatively, these dimensions can be chosen from other suitable sizes.

[0035] In the above embodiments, such as Figure 1 As shown, preferably, at least two carrier channels 7 are used.

[0036] like Figure 2 As shown, the present invention also provides a hot-wire CVD photovoltaic cell edge passivation device, comprising: a feeding area 1; a process area 2, the process area 2 being connected to the feeding area 1; and a discharging area 3, the discharging area 3 being connected to the process area 2; wherein the process area 2 includes, from top to bottom along the height direction: a cavity 4 as described above; a vacuum system 5, the vacuum system 5 being connected to the cavity 4, for providing and maintaining a vacuum environment for the cavity 4; and an empty material box return conveyor line 6, the empty material box return conveyor line 6 returning the empty material box from the discharging area 3 to the feeding area 1.

[0037] The invention features a continuous layout of the loading area, processing area, and unloading area, and integrates an empty material box return conveyor line, making the material flow path simple and smooth. This design reduces manual intervention and material turnover time, supports continuous and automated operation of the production line, and improves the overall equipment utilization rate and capacity.

[0038] In the above embodiments, such as Figure 2 and 3As shown, the cavity 4 includes a feed cavity 41, at least one process cavity (e.g., a first process cavity 42 and a second process cavity 43) and a discharge cavity 44 connected in sequence by sealing. The feed cavity 41, at least one process cavity and the discharge cavity 44 all adopt the cavity structure described above. The feed cavity 41 buffers the carrier plate 8 carrying the uncoated silicon wafer cassette transported from the front-end conveying system and heats the carrier plate 8, and then conveys the carrier plate 8 into the process cavity. The process cavity deposits a passivation film layer on the silicon wafer. The discharge cavity 44 anneals the coated silicon wafer and outputs the carrier plate 8.

[0039] In the above embodiments, such as Figure 2 and 3 As shown, at least one process cavity includes a first process cavity 42 and a second process cavity 43, and the first process cavity 42 and the second process cavity 43 respectively deposit passivation film layers of different materials on the silicon wafer.

[0040] In the above embodiments, such as Figure 3 As shown, the cavities in the process area (feed cavity 41, first process cavity 42, second process cavity 43, and discharge cavity 44) are configured to simultaneously accommodate and process two carrier plates 8. Each carrier plate 8 is constructed to carry multiple wafer trays (wafer trays are carriers for loading silicon wafers; one wafer tray can hold multiple silicon wafers) along its length, and the wafer trays can be stacked in multiple layers along its height. Within the cavity, the coating working surfaces of the two carrier plates 8 are arranged opposite each other. The coating position is on the opposite surfaces of the two carrier plates 8. The dual-carrier plate design can double the production capacity. The cavity structure of this invention can support, for example, a dual-carrier plate arrangement opposite each other, multi-layer wafer tray stacking, and can flexibly connect multiple cavities to form a multi-process continuous processing system. This design enables the equipment to adapt to the edge passivation requirements of silicon wafers of different sizes and can achieve more complex process integration through modular expansion, enhancing the equipment's industrial adaptability and future development potential.

[0041] In the above embodiments, the process area has maintenance platforms and basic equipment located below the maintenance platforms on both sides along the width direction. The maintenance platforms are positioned at the height of the cavity and perform maintenance operations on the cavity. The cavity structure of the present invention can support, for example, the opposite arrangement of dual carrier boards, the stacking of multiple material boxes, and can flexibly connect multiple cavities to form a multi-process continuous processing system. This design enables the equipment to adapt to the edge passivation requirements of silicon wafers of different sizes and can achieve more complex process integration through modular expansion, enhancing the equipment's industrial adaptability and future development potential.

[0042] The above technical solutions of the present invention will be described in detail below through specific embodiments.

[0043] This invention provides an edge passivation device for photovoltaic cells specifically designed for hot-filament chemical vapor deposition (CVD) processes, along with its core vacuum chamber. The core of this solution lies in a highly optimized and standardized modular design of the chamber, upon which an automated, highly efficient continuous production system is built. The following embodiments are intended to exemplify specific implementations of this invention and are not intended to limit the scope of protection of this invention.

[0044] Example 1 A cavity for hot-wire CVD photovoltaic cell edge passivation equipment See Figure 1 This embodiment 1 provides a rectangular vacuum cavity 4. This cavity 4 constitutes the basic functional unit of the entire device, and its external structural dimensions have been precisely calculated and optimized, as follows: Length (first dimension x): 2.0 meters. This dimension allows the cavity 4 to accommodate a sufficient number of process components (such as hot wire sources and gas distribution systems) and the operating space of the carrier plate 8 in the length direction, while maintaining overall compactness.

[0045] Width (second dimension y): 0.85 meters. This width is specifically optimized for the dual-carrier parallel processing mode, providing ample and interference-free lateral space for the two carriers 8 and the process area (such as hot wire array) between them.

[0046] Height (third dimension z): 1.25 meters. This height fully considers the needs of multi-layer box stacking and the necessary internal mechanical and electrical layout space.

[0047] Two identical carrier channels 7 are formed in parallel on one end wall 11 (or both end walls, depending on their position in the production line as an inlet / outlet or connecting chamber) along the length of the cavity 4. Each carrier channel 7 has a width (fourth dimension b) of 0.15 meters and a height (fifth dimension h) of 0.57 meters. This size is sufficient to ensure that carriers 8 loaded with stacked multi-layered boxes can pass smoothly and steadily, while minimizing the opening area to facilitate vacuum sealing. Furthermore, the width b of the carrier channel and the width y of the cavity satisfy a proportional relationship: b = ky, where the proportionality coefficient k is approximately 0.176 (0.15 / 0.85). This proportional relationship is an optimized result verified by fluid dynamics and structural mechanics simulations, maximizing the space utilization of the cavity while ensuring smooth carrier passage and structural strength.

[0048] Each carrier channel 7 is equipped with a flap valve sealing assembly (not shown separately in the figure) on its outer side. When the carrier 8 needs to enter or exit, the flap valve opens; when the cavity 4 needs to maintain process vacuum, the flap valve closes tightly and its sealing ring fits tightly against the cavity end wall 11 to ensure extremely high vacuum sealing and effectively prevent gas leakage.

[0049] At the bottom of cavity 4, specifically on the lower wall 10 along the height direction, two molecular pump interfaces 9 are symmetrically arranged. In this embodiment 1, the diameter of interface 9 is 0.32 meters, used to connect a high-speed molecular pump. Placing the evacuation interfaces at the bottom of the cavity facilitates the natural settling of byproduct gases and unreacted gases generated during the process under the influence of gravity and the flow field, allowing them to be quickly and uniformly removed. This "bottom-evacuation" layout significantly shortens the vacuuming time and maintains a more stable and uniform vacuum level during the process, laying the foundation for high-quality thin film deposition.

[0050] Example 2 A cavity for hot-wire CVD photovoltaic cell edge passivation equipment See Figure 1 This embodiment 2 provides a rectangular vacuum cavity 4. This cavity 4 constitutes the basic functional unit of the entire device, and its external structural dimensions have been precisely calculated and optimized, as follows: Length (first dimension x): 1.0 meter. This dimension allows the cavity 4 to accommodate a sufficient number of process components (such as hot wire sources and gas distribution systems) and the operating space of the carrier plate 8 in the length direction, while maintaining overall compactness.

[0051] Width (second dimension y): 1.2 meters. This width is specifically optimized for dual-carrier parallel processing mode, providing ample and interference-free lateral space for the two carriers 8 and the process area (such as hot wire array) between them.

[0052] Height (third dimension z): 0.8 meters. This height fully considers the needs of multi-layered box stacking and the necessary internal mechanical and electrical layout space.

[0053] Two identical carrier channels 7 are formed in parallel on one end wall 11 (or both end walls, depending on their position in the production line as an inlet / outlet or connecting chamber) along the length of the cavity 4. Each carrier channel 7 has a width (fourth dimension b) of 0.1 meters and a height (fifth dimension h) of 0.32 meters. This size is sufficient to ensure that carriers 8 loaded with stacked multi-layered boxes can pass smoothly and steadily, while minimizing the opening area to facilitate vacuum sealing. Furthermore, the width b of the carrier channel and the width y of the cavity satisfy a proportional relationship: b = ky, where the proportionality coefficient k is approximately 0.083 (0.1 / 1.2). This proportional relationship is an optimized result verified by fluid dynamics and structural mechanics simulations, maximizing the space utilization of the cavity while ensuring smooth carrier passage and structural strength.

[0054] Each carrier channel 7 is equipped with a flap valve sealing assembly (not shown separately in the figure) on its outer side. When the carrier 8 needs to enter or exit, the flap valve opens; when the cavity 4 needs to maintain process vacuum, the flap valve closes tightly and its sealing ring fits tightly against the cavity end wall 11 to ensure extremely high vacuum sealing and effectively prevent gas leakage.

[0055] At the bottom of cavity 4, specifically on the lower wall 10 along the height direction, two molecular pump interfaces 9 are symmetrically arranged. In this embodiment 2, the diameter of interface 9 is 0.4 meters, used to connect a high-speed molecular pump. Placing the evacuation interfaces at the bottom of the cavity facilitates the natural settling of byproduct gases and unreacted gases generated during the process under the influence of gravity and the flow field, allowing them to be quickly and uniformly removed. This "bottom-evacuation" layout significantly shortens the vacuuming time and maintains a more stable and uniform vacuum level during the process, laying the foundation for high-quality thin film deposition.

[0056] Example 3 A cavity for hot-wire CVD photovoltaic cell edge passivation equipment See Figure 1 This embodiment 3 provides a rectangular vacuum cavity 4. This cavity 4 constitutes the basic functional unit of the entire device, and its external structural dimensions have been precisely calculated and optimized, as follows: Length (first dimension x): 3.0 meters. This dimension allows the cavity 4 to accommodate a sufficient number of process components (such as hot wire sources and gas distribution systems) and the operating space of the carrier plate 8 in the length direction, while maintaining overall compactness.

[0057] Width (second dimension y): 0.6 meters. This width is specifically optimized for dual-carrier parallel processing mode, providing ample and interference-free lateral space for the two carriers 8 and the process area (such as hot wire array) between them.

[0058] Height (third dimension z): 3.0 meters. This height fully considers the needs of multi-layered box stacking and the necessary internal mechanical and electrical layout space.

[0059] Two identical carrier channels 7 are formed in parallel on one end wall 11 (or both end walls, depending on their position in the production line as an inlet / outlet or connecting chamber) along the length of the cavity 4. Each carrier channel 7 has a width (fourth dimension b) of 0.3 meters and a height (fifth dimension h) of 2.0 meters. This size is sufficient to ensure that carriers 8 loaded with stacked multi-layered boxes can pass smoothly and steadily, while minimizing the opening area to facilitate vacuum sealing. Furthermore, the width b of the carrier channel and the width y of the cavity satisfy a proportional relationship: b = ky, where the proportionality coefficient k is approximately 0.5 (0.3 / 0.6). This proportional relationship is an optimized result verified by fluid dynamics and structural mechanics simulations, maximizing the space utilization of the cavity while ensuring smooth carrier passage and structural strength.

[0060] Each carrier channel 7 is equipped with a flap valve sealing assembly (not shown separately in the figure) on its outer side. When the carrier 8 needs to enter or exit, the flap valve opens; when the cavity 4 needs to maintain process vacuum, the flap valve closes tightly and its sealing ring fits tightly against the cavity end wall 11 to ensure extremely high vacuum sealing and effectively prevent gas leakage.

[0061] At the bottom of cavity 4, specifically on the lower wall 10 along the height direction, two molecular pump interfaces 9 are symmetrically arranged. In this embodiment 3, the diameter of interface 9 is 0.16 meters, used to connect a high-speed molecular pump. Placing the evacuation interfaces at the bottom of the cavity facilitates the natural settling of byproduct gases and unreacted gases generated during the process under the influence of gravity and the flow field, allowing them to be quickly and uniformly removed. This "bottom-evacuation" layout significantly shortens the vacuuming time and maintains a more stable and uniform vacuum level during the process, laying the foundation for high-quality thin film deposition.

[0062] Example 4 A hot-filament CVD photovoltaic cell edge passivation device comprising a cavity according to Embodiment 1, Embodiment 2, or Embodiment 3. See Figure 2 and Figure 3 This embodiment 4 provides a complete edge passivation production equipment. The equipment adopts a highly integrated modular layout and is mainly divided into a feeding area 1, a process area 2, and a discharging area 3.

[0063] The core components of process area 2: Process area 2 is the core of the equipment, and it adopts a vertical three-dimensional design to save floor space.

[0064] Cavity module: such as Figure 3As shown, multiple standardized cavities 4 designed according to Embodiment 1, Embodiment 2, or Embodiment 3 are sequentially connected via a high-vacuum gate valve (not shown in the figure) to form a continuous vacuum processing tunnel. Specifically, this includes: Feed chamber 41: As a vacuum lock, it receives the carrier board 8, which carries the uncoated silicon wafer cassette, from the loading area 1 via the conveying system. It has a buffer function and pre-vacuums and heats the carrier board 8 in preparation for entering the process chamber.

[0065] First process chamber 42 and second process chamber 43: These two chambers integrate the core components required for hot-filament CVD deposition, such as the hot-filament array, precision gas spray system, and temperature control system. First process chamber 42 is used to deposit the first passivation film (such as silicon oxide SiO2), and second process chamber 43 is used to deposit the second passivation film (such as silicon nitride SiN). x This achieves edge passivation of the composite film layer, thereby improving battery performance.

[0066] Discharge chamber 44: The silicon wafer that has been coated is subjected to necessary annealing treatment to stabilize the film performance, then slowly cooled and ventilated, and finally the carrier board 8 is output to the unloading area 3.

[0067] All of these functional chambers (41, 42, 43, 44) adopt the standardized cavity 4 structure described in Embodiment 1, Embodiment 2 or Embodiment 3, ensuring modularity, consistency and ease of maintenance in equipment manufacturing.

[0068] Vacuum system 5: Connected to the molecular pump interface 9 of each chamber through a pipeline network, it provides and maintains vacuum environments of various levels from low vacuum to high vacuum for the entire process area 2.

[0069] Empty material box return conveyor line 6: Located on the lower level of the equipment, it is a closed automated conveyor line. It automatically and continuously transports the empty material boxes after unloading silicon wafers from the unloading area 3 back to the loading area 1, realizing the recycling of material boxes, greatly reducing manual handling and material turnover time, and improving production continuity.

[0070] In this embodiment 4, the equipment is located inside a process chamber (first process chamber 42 or second process chamber 43), and the processing mode is optimized to achieve maximum capacity (see...). Figure 3 Two carrier plates 8 are fed side-by-side into each cavity, with their coating working surfaces (i.e., the sides that support the silicon wafers and whose edges face the center of the cavity) positioned opposite each other. A deposition source, such as a hot filament array (not shown), is located in the central region between the two rows of carrier plates 8. Each carrier plate 8 can support multiple wafer trays along its length, and each wafer tray can stack multiple layers of silicon wafers along its height. This configuration allows the deposition source to simultaneously and uniformly coat the edges of all silicon wafers (dual carrier plates, multiple wafer trays, multiple layers), maximizing space utilization and single-pass throughput.

[0071] In addition, such as Figure 2 As shown in the figure, in this embodiment 4, the equipment has robust maintenance platforms (not shown) built on both sides of the process area 2 along the width direction. The height of these platforms matches the installation positions of the operating windows, observation windows, valves, and sensors in the cavity 4. The space below the platforms is used to centrally arrange basic equipment such as vacuum pump units, power cabinets, gas cabinets, and control cabinets. This layout allows operators and maintenance personnel to safely and conveniently access all critical components for daily inspections, parameter adjustments, component replacements, and troubleshooting, significantly improving the operability and maintainability of the equipment and reducing the mean time to repair (MTBT).

[0072] The overall workflow of the equipment in Example 4 is as follows: Loading: In loading area 1, place the cassette containing uncoated silicon wafers onto carrier plate 8.

[0073] Feeding and pretreatment: Carrier plate 8 enters the feeding chamber 41 through the conveying system and is evacuated.

[0074] Multilayer coating: The carrier plate 8 passes through the first process cavity 42 and the second process cavity 43 in sequence to deposit edge passivation film layers of different materials respectively.

[0075] Post-processing and unloading: The coated carrier board 8 enters the discharge chamber 44 for annealing, and then is conveyed to the unloading area 3 to unload the coated silicon wafers.

[0076] Return: Empty material boxes (including empty plates on them) are returned to prepare for the next cycle. The empty material boxes are automatically returned to the loading area 1 via the return conveyor line 6.

[0077] As can be seen, this invention provides a standardized and structurally optimized vacuum chamber, and on this basis, a highly automated and integrated production equipment is built. It comprehensively solves the bottlenecks of existing technologies in multiple dimensions, such as increasing production capacity (dual carrier parallel), ensuring quality (stable vacuum and uniform coating), improving efficiency (automated reflow and continuous production), and enhancing maintainability. It provides reliable equipment support for the efficient and high-quality edge passivation production of photovoltaic cells.

[0078] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to the process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0079] The above description is merely an embodiment of the present invention, which enables those skilled in the art to understand and implement the invention. Various modifications to the embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

Claims

1. A cavity for edge passivation equipment of hot-wire CVD photovoltaic cells, characterized in that, The cavity is a rectangular vacuum cavity, including a first dimension x along the length direction, a second dimension y along the width direction, and a third dimension z along the height direction; The cavity has at least two carrier channels arranged in parallel on its end wall along the length direction for at least two carrier plates to pass through. Each carrier channel has a fourth dimension b along the width direction and a fifth dimension h along the height direction. Each carrier channel is provided with a flap valve sealing assembly, which is used to control the opening and closing and sealing of the carrier channel to ensure the vacuum environment of the cavity. The cavity is provided with a molecular pump interface on at least one of the front wall along the width direction, the rear wall along the width direction, and the lower wall along the height direction. The molecular pump interface is used to connect a molecular pump to extract gas from the cavity to maintain a vacuum environment. Among them, 1.0m≤x≤3.0m, 0.6m≤y≤1.2m, 0.8m≤z≤3.0m; 0.1m≤b≤0.3m, 0.32m≤h≤2.0m.

2. The cavity of the hot-filament CVD photovoltaic cell edge passivation device according to claim 1, characterized in that, The fourth dimension b and the second dimension y satisfy a proportional relationship: b=ky, where the proportionality coefficient k ranges from 0.083 to 0.

5.

3. The cavity of the hot-filament CVD photovoltaic cell edge passivation device according to claim 1, characterized in that, The diameter of the molecular pump interface is selected from any one of 0.16m, 0.2m, 0.25m, 0.32m or 0.4m.

4. The cavity of the hot-wire CVD photovoltaic cell edge passivation device according to claim 1, characterized in that, The first dimension x = 2m, the second dimension y = 0.85m, and the third dimension z = 1.25m; The fourth dimension b = 0.15m, and the fifth dimension h = 0.57m.

5. The cavity of the hot-wire CVD photovoltaic cell edge passivation device according to claim 1, characterized in that, The at least two carrier channels are two carrier channels, and the molecular pump interface is at least two molecular pump interfaces.

6. A hot-filament CVD photovoltaic cell edge passivation device, characterized in that, include: Material loading area; The process area is connected to the loading area; and The material feeding area is connected to the process area; The process area, from top to bottom along the height direction, includes: The cavity as described in any one of claims 1-5; A vacuum system, connected to the cavity, for providing and maintaining a vacuum environment for the cavity; An empty material box return conveyor line returns empty material boxes from the unloading area to the loading area.

7. The hot-filament CVD photovoltaic cell edge passivation device according to claim 6, characterized in that, The cavity includes a feeding cavity, at least one process cavity, and a discharging cavity that are sequentially sealed and connected. The feeding cavity, the at least one process cavity, and the discharging cavity all adopt the structure of the cavity as described in any one of claims 1-5. The feeding cavity buffers a carrier plate carrying an uncoated silicon wafer cassette transported from the front-end conveying system and heats the carrier plate before conveying it into the process cavity. The process cavity deposits a passivation film layer on the silicon wafer. The discharging cavity anneals the coated silicon wafer and outputs the carrier plate.

8. The hot-filament CVD photovoltaic cell edge passivation device according to claim 7, characterized in that, At least one process cavity includes a first process cavity and a second process cavity, wherein the first process cavity and the second process cavity respectively deposit passivation film layers of different materials on the silicon wafer.

9. The hot-filament CVD photovoltaic cell edge passivation device according to claim 6, characterized in that, The cavity in the process area is configured to simultaneously accommodate and process two carrier plates. Each carrier plate is constructed to carry multiple material boxes in the length direction, and the material boxes can be stacked into multiple layers in the height direction. Furthermore, the coating working surfaces of the two carrier plates are arranged opposite each other within the cavity.

10. The hot-filament CVD photovoltaic cell edge passivation device according to claim 6, characterized in that, The process area has maintenance platforms and basic equipment located below the maintenance platforms on both sides along the width direction. The maintenance platforms are set at the height of the cavity and are used to perform maintenance operations on the cavity.

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