Constant-temperature TOPCon battery production diffusion furnace

Abstract

The invention relates to the technical field of battery production diffusion furnaces, in particular to a constant-temperature TOPCon battery production diffusion furnace which comprises a heating furnace body, a high-temperature diffusion mechanism used for preparing a PN junction through boron diffusion is arranged in the heating furnace body, and a furnace body gas supply mechanism used for adjusting the concentration of a boron source is arranged on the heating furnace body. The high-temperature diffusion mechanism can conduct gas preheating on the furnace body gas supply mechanism, the high-temperature diffusion mechanism comprises a heating ring pipe, the heating ring pipe is arranged in the side wall of the heating furnace body in a surrounding mode, and a phase change material layer is arranged on the inner side wall of the heating furnace body. The high-temperature diffusion mechanism is arranged, the heating ring pipe is tightly matched with the phase change material layer, and efficient heat conduction of the heat dissipation plate assembly is combined, so that the influence of temperature fluctuation of the heating ring pipe on the temperature in the furnace is effectively buffered, and the temperature fluctuation range in the furnace can be controlled within + / -1 DEG C; the uniformity and repeatability of the boron diffusion process are remarkably improved, and a stable high-temperature environment is provided for PN junction preparation of a TOPCon battery.

Description

Technical Field

[0001] This invention relates to the field of diffusion furnace technology for battery production, and more particularly to a constant-temperature TOPCon battery production diffusion furnace. Background Technology

[0002] In the manufacturing process of TOPCon batteries, the boron diffusion process is a key step in forming the PN junction. Its process quality directly affects the conversion efficiency and performance stability of the battery. Traditional boron diffusion processes mainly use tubular diffusion furnaces, which have insufficient temperature control precision and low energy utilization efficiency.

[0003] In response, the prior art patent document with publication number CN202420681313 proposes a diffusion furnace for TOPCon battery cell production with an exhaust gas circulation structure. Although it proposes a scheme to preheat the intake gas using exhaust gas, it only adopts a simple heat exchange structure, and the preheating effect is limited, still unable to solve the problem of temperature uniformity inside the furnace. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a constant-temperature diffusion furnace for TOPCon battery production, which solves the technical problems of low temperature control accuracy and energy utilization in existing diffusion furnaces. It also has the advantages of effectively improving the uniformity of furnace temperature and energy utilization during the gas intake process.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a constant-temperature TOPCon battery production diffusion furnace, including a heating furnace body. The heating furnace body is equipped with a high-temperature diffusion mechanism for boron diffusion to prepare PN junctions. The heating furnace body is also equipped with a furnace gas supply mechanism for adjusting the boron source concentration. The high-temperature diffusion mechanism preheats the gas supplied by the furnace body. After the operator places a quartz boat into the heating furnace body, the high-temperature diffusion mechanism and the furnace gas supply mechanism automatically perform the boron diffusion process on the quartz boat. The high-temperature diffusion mechanism includes a heating ring tube, which is arranged around the inside of the side wall of the heating furnace body. A phase change material layer is provided on the inner side wall of the heating furnace body, and a heat sink assembly is detachably installed on the phase change material layer. A lifting support rod is fixedly installed inside the heating furnace body, and a rectangular frame for placing the quartz boat is provided on the lifting support rod. During the boron diffusion process, the heating ring tube is automatically energized to generate high temperature. Subsequently, the heat diffuses into the interior of the heating furnace body through multiple sets of heat sink assemblies. Simultaneously, the furnace gas supply mechanism sequentially delivers various gases into the interior of the heating furnace body, thereby completing the boron diffusion process.

[0006] Preferably, the rectangular frame is symmetrically provided with support frame assemblies, and the two support frame assemblies can move closer or further apart under the action of the telescopic rod, thereby adapting to quartz boats of different sizes.

[0007] Preferably, the heating ring tube is closely bonded to the phase change material layer, which can effectively improve the efficiency of heat conduction and ensure the heating effect.

[0008] Preferably, the furnace body gas supply mechanism includes a gas supply pipe for supplying gas into the interior of the heating furnace body. A small air pump is fixedly installed on the heating furnace body. The air inlet of the small air pump is connected to a suction pipe, and the air outlet of the small air pump is connected to an exhaust pipe. The gas enters the heating furnace body through the gas supply pipe, and after the reaction is completed, it will be discharged outward through the exhaust pipe under the suction action of the small air pump.

[0009] Preferably, the exhaust pipe is spirally wound around the outside of the gas supply pipe, thereby utilizing the residual heat of the exhaust gas to preheat the reaction gas initially.

[0010] Preferably, the gas supply pipe is arranged around the inner cavity of the heating furnace and is located between the two sets of heat dissipation plate assemblies. This allows for secondary preheating of the gas in the pipe before the reaction gas is discharged, thereby reducing the temperature difference caused to the interior of the heating furnace during the gas filling process.

[0011] Preferably, the suction pipe extends into the interior of the heating furnace body. When the small air pump is powered on, it will automatically draw the high-temperature exhaust gas inside the heating furnace body out through the suction pipe.

[0012] By employing the above technical solution, the present invention provides a constant-temperature diffusion furnace for TOPCon battery production, which has at least the following beneficial effects: 1. By setting up a high-temperature diffusion mechanism, the present invention effectively buffers the impact of heating ring temperature fluctuations on the furnace temperature through the close cooperation between the heating ring tube and the phase change material layer, combined with the efficient heat conduction of the heat sink assembly. This allows the furnace temperature fluctuation range to be controlled within ±1℃, significantly improving the uniformity and repeatability of the boron diffusion process and providing a stable high-temperature environment for the preparation of PN junctions in TOPCon batteries.

[0013] 2. By setting up a high-temperature diffusion mechanism, the present invention can automatically adapt to quartz boats of different sizes (compatible with silicon wafers from 125mm to 210mm) through the coordinated design of lifting struts and adjustable spacing support frame components. It can also ensure that the quartz boat is always accurately positioned in the central area of ​​the furnace body where the thermal field is most uniform, thus ensuring that different batches of silicon wafers can obtain the best thermal environment.

[0014] 3. By setting up a furnace body gas supply mechanism and adopting a dual gas preheating system, the present invention first achieves primary preheating by spirally winding the exhaust pipe around the gas supply pipe, and then achieves secondary preheating by the gas supply pipe winding between two sets of heat dissipation plate assemblies. This allows the reaction gas to gradually approach the working temperature inside the furnace during the transportation process, which can effectively reduce the temperature difference when the reaction gas enters the furnace body and greatly reduce the disturbance of the furnace temperature caused by gas injection.

[0015] 4. By setting up a furnace body gas supply mechanism, the gas intake pipe extends directly into the furnace body to quickly extract reaction byproducts and prevent waste gas from accumulating and affecting diffusion quality. In addition, the spirally wound exhaust pipe can not only preheat the new gas, but also reduce the waste gas temperature through heat exchange, which greatly reduces the waste gas emission temperature and effectively improves safety.

[0016] 5. By setting up a high-temperature diffusion mechanism, the detachable design of the heat sink assembly, and the modular arrangement of the phase change material layer, the present invention enables key heat conduction components to be maintained or replaced individually, greatly reducing the difficulty of equipment maintenance and downtime. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a perspective view of the overall structure of the present invention; Figure 2 This is a cross-sectional view of a portion of the structure in this invention; Figure 3 This is a schematic diagram of the furnace body gas supply mechanism in this invention; Figure 4 This is a schematic diagram of the high-temperature diffusion mechanism in this invention; Figure 5 This is a schematic diagram of the support frame assembly in this invention.

[0018] In the diagram: 1. Heating furnace body; 2. Furnace door; 3. High-temperature diffusion mechanism; 301. Heating ring pipe; 302. Phase change material layer; 303. Heat sink assembly; 304. Lifting strut; 305. Rectangular frame; 306. Support frame assembly; 4. Furnace body gas supply mechanism; 401. Gas supply pipe; 402. Small air pump; 403. Intake pipe; 404. Exhaust pipe; 5. Quartz boat. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1 While existing diffusion furnaces utilize exhaust gas preheating for inlet gas, they employ only simple heat exchange structures, resulting in limited preheating effectiveness and failing to address the issue of uniform temperature within the furnace. To overcome this technical deficiency in existing technologies, such as... Figures 1-4 As shown, this embodiment proposes a constant-temperature diffusion furnace for TOPCon battery production, which effectively buffers the influence of temperature fluctuations in the heating ring tube 301 on the furnace temperature, allowing the furnace temperature fluctuation range to be controlled within ±1℃. The furnace includes a heating furnace body 1, with a furnace door 2 movably installed on the outside of the heating furnace body 1. The interior of the heating furnace body 1 is equipped with a high-temperature diffusion mechanism 3 for boron diffusion to prepare PN junctions. The heating furnace body 1 is equipped with a furnace gas supply mechanism 4 for adjusting the boron source concentration. The high-temperature diffusion mechanism 3 can preheat the gas in the furnace gas supply mechanism 4. After the operator puts the quartz boat 5 into the heating furnace body 1, the high-temperature diffusion mechanism 3 and the furnace gas supply mechanism 4 will automatically perform the boron diffusion process on the quartz boat 5.

[0021] Specifically, the high-temperature diffusion mechanism 3 includes a heating ring tube 301, which is arranged around the inside of the side wall of the heating furnace body 1. A phase change material layer 302 is provided on the inner side wall of the heating furnace body 1. The heating ring tube 301 and the phase change material layer 302 are closely attached to each other, which can effectively improve the efficiency of heat conduction and ensure the heating effect. A heat dissipation plate assembly 303 is detachably installed on the phase change material layer 302. A lifting support rod 304 is fixedly installed inside the heating furnace body 1. A rectangular frame 305 for placing a quartz boat is provided on the lifting support rod 304. During the boron diffusion process, the heating ring tube 301 will automatically be energized to generate high temperature. Subsequently, the heat will diffuse into the interior of the heating furnace body 1 through multiple sets of heat dissipation plate assemblies 303. At the same time, the furnace body gas supply mechanism 4 will sequentially deliver various gases into the interior of the heating furnace body 1 to complete the boron diffusion process. Support frame assemblies 306 are symmetrically arranged on the rectangular frame 305. The two support frame assemblies 306 can move closer or further apart under the action of the telescopic rod to adapt to quartz boats of different sizes.

[0022] As can be seen from the above, when using this diffusion furnace for boron diffusion processing, the staff will first place the quartz boat 5 containing the TOPCon battery onto the rectangular frame 305 through the furnace door 2, and then close the furnace door 2.

[0023] Subsequently, the heating ring tube 301 will automatically be powered on and heated. Next, the heat generated by the heating ring tube 301 will be rapidly diffused into the interior of the heating furnace body 1 through the phase change material layer 302 and the heat sink assembly 303, thereby keeping the TOPCon battery at a high temperature. At the same time, the furnace body gas supply mechanism 4 will sequentially deliver various gases (boron tribromide, boron trichloride, nitrogen, etc.) into the interior of the heating furnace body 1 to complete the boron diffusion process.

[0024] Moreover, the height of the rectangular frame 305 can be freely adjusted under the action of the lifting support rod 304, which can ensure that the quartz boat 5 is always located in the middle of the heating furnace body 1, and can improve the efficiency of high-temperature boron diffusion to a certain extent.

[0025] In addition, the spacing between the two support frame assemblies 306 is adjustable, making it suitable for various sizes of quartz boats 5 and easy to use.

[0026] This embodiment, by setting up a high-temperature diffusion mechanism 3, effectively buffers the impact of temperature fluctuations in the heating ring tube 301 on the furnace temperature through the close cooperation between the heating ring tube 301 and the phase change material layer 302, combined with the efficient heat conduction of the heat sink assembly 303. This allows the furnace temperature fluctuation range to be controlled within ±1℃, significantly improving the uniformity and repeatability of the boron diffusion process and providing a stable high-temperature environment for the fabrication of PN junctions in TOPCon cells. Moreover, by setting up the high-temperature diffusion mechanism 3, and through the coordinated design of the lifting support rod 304 and the adjustable spacing support frame assembly 306, this embodiment can automatically adapt to quartz boats 5 of different sizes (compatible with silicon wafer specifications from 125mm to 210mm), and ensure that the quartz boat 5 is always precisely positioned in the central area of ​​the furnace body where the thermal field is most uniform, ensuring that different batches of silicon wafers can obtain the best thermal environment. In addition, by setting up the high-temperature diffusion mechanism 3, the detachable design of the heat sink assembly 303, and the modular arrangement of the phase change material layer 302, this embodiment allows key heat conduction components to be maintained or replaced individually, greatly reducing equipment maintenance difficulty and downtime.

[0027] Example 2 To ensure that the reactant gas gradually approaches the furnace operating temperature during transport, reduce the temperature difference when the reactant gas enters the furnace, and minimize the disturbance to the furnace temperature caused by gas injection, based on Example 1, as follows: Figures 2-5As shown, this embodiment includes a furnace body gas supply mechanism 4. Specifically, the furnace body gas supply mechanism 4 includes a gas supply pipe 401, which surrounds the inner cavity of the heating furnace body 1. The gas supply pipe 401 is located between two sets of heat dissipation plate assemblies 303, and can preheat the gas in the pipe before the reaction gas is discharged, thereby reducing the temperature difference caused to the interior of the heating furnace body 1 during the gas filling process. The gas supply pipe 401 is used to supply gas to the interior of the heating furnace body 1. A small air pump 402 is fixedly installed on the heating furnace body 1, and the air inlet of the small air pump 402 is connected to a suction pipe 4. 03. The suction pipe 403 extends into the interior of the heating furnace body 1. When the small air pump 402 is powered on, it will automatically draw the high-temperature waste gas inside the heating furnace body 1 out through the suction pipe 403. The outlet end of the small air pump 402 is connected to the exhaust pipe 404. The gas enters the heating furnace body 1 through the gas supply pipe 401. After the reaction is completed, it will be discharged out through the exhaust pipe 404 under the suction action of the small air pump 402. The exhaust pipe 404 is spirally wrapped around the outside of the gas supply pipe 401, thereby using the residual heat of the discharged waste gas to preheat the reaction gas.

[0028] As can be seen from the above, during the boron diffusion process, the reaction gases (boron tribromide, boron trichloride, nitrogen, etc.) will enter the interior of the heating furnace 1 sequentially through the gas supply pipe 401.

[0029] After the reaction is complete, the small air pump 402 will use the suction pipe 403 to extract the high-temperature waste gas inside the heating furnace 1 and discharge it to the outside through the exhaust pipe 404. Furthermore, if... Figure 2 As shown, the exhaust pipe 404 is wrapped around the outside of the gas supply pipe 401, and can automatically preheat the gas inside the gas supply pipe 401.

[0030] In addition, after the gas enters the interior of the heating furnace body 1 through the gas supply pipe 401, the heat dissipation plate assembly 303 located on both sides of the gas supply pipe 401 can preheat the gas in the pipe, thereby minimizing the temperature change caused by the gas entering the furnace body.

[0031] This embodiment employs a dual gas preheating system by setting up a furnace body gas supply mechanism 4. First, the gas supply pipe 401 is spirally wound around the exhaust pipe 404 to achieve primary preheating. Then, the gas supply pipe 401 is wound between two sets of heat dissipation plate assemblies 303 to achieve secondary preheating. This allows the reaction gas to gradually approach the furnace working temperature during the transportation process, effectively reducing the temperature difference when the reaction gas enters the furnace body and significantly reducing the disturbance of the furnace temperature caused by gas injection. Moreover, by setting up a furnace body gas supply mechanism 4, the suction pipe 403 extends directly into the furnace body to quickly extract reaction byproducts, preventing the accumulation of waste gas from affecting the diffusion quality. In addition, the spirally wound exhaust pipe 404 not only preheats the new gas but also reduces the waste gas temperature through heat exchange, greatly reducing the waste gas emission temperature and effectively improving safety.

[0032] The control method of this invention is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art. The power supply is also common knowledge in the art. Furthermore, since this invention is mainly used to protect mechanical devices, the control method and circuit connection will not be explained in detail here.

[0033] It should be noted that, in this document, 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 such process, method, article, or apparatus.

[0034] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A constant-temperature diffusion furnace for TOPCon battery production, comprising a heating furnace body (1), characterized in that: The interior of the heating furnace body (1) is provided with a high-temperature diffusion mechanism (3) for preparing PN junctions by boron diffusion, and the heating furnace body (1) is provided with a furnace body gas supply mechanism (4) for adjusting the boron source concentration. The high-temperature diffusion mechanism (3) can preheat the gas supply mechanism (4). The high-temperature diffusion mechanism (3) includes a heating ring tube (301), which is arranged around the inside of the side wall of the heating furnace body (1). A phase change material layer (302) is provided on the inner side wall of the heating furnace body (1). A heat dissipation plate assembly (303) is detachably installed on the phase change material layer (302). A lifting support rod (304) is fixedly installed inside the heating furnace body (1). A rectangular frame (305) for placing a quartz boat is provided on the lifting support rod (304).

2. The isothermal TOPCon battery production diffusion furnace according to claim 1, characterized in that: Support frame assemblies (306) are symmetrically arranged on the rectangular frame (305).

3. The isothermal diffusion furnace for TOPCon battery production according to claim 1, characterized in that: The heating ring tube (301) is tightly bonded to the phase change material layer (302).

4. The isothermal TOPCon battery production diffusion furnace according to claim 1, characterized in that: The furnace body gas supply mechanism (4) includes a gas supply pipe (401), which is used to supply gas to the interior of the heating furnace body (1). A small air pump (402) is fixedly installed on the heating furnace body (1). The air inlet of the small air pump (402) is connected to a suction pipe (403), and the air outlet of the small air pump (402) is connected to an exhaust pipe (404).

5. The isothermal TOPCon battery production diffusion furnace according to claim 4, characterized in that: The exhaust pipe (404) is spirally wound around the outside of the gas supply pipe (401).

6. The isothermal TOPCon battery production diffusion furnace according to claim 4, characterized in that: The gas supply pipe (401) surrounds the inner cavity of the heating furnace body (1) and is located between the two sets of heat dissipation plate assemblies (303).

7. The isothermal TOPCon battery production diffusion furnace according to claim 4, characterized in that: The air intake pipe (403) extends into the interior of the heating furnace body (1).

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