Gas environment management system and method and silicon carbide epitaxial furnace

Abstract

The invention provides a gas environment management system and method and a silicon carbide epitaxial furnace, and the silicon carbide epitaxial furnace comprises a reaction cabin, a feeding and discharging cabin, a transfer cabin and the gas environment management system. The gas environment management system is independently connected with a reaction cabin of the silicon carbide epitaxial furnace, a transfer cabin of the silicon carbide epitaxial furnace and a feeding and discharging cabin of the silicon carbide epitaxial furnace, and the gas environment management system independently controls the gas environment of the reaction cabin, the transfer cabin and the feeding and discharging cabin. When a chemical vapor deposition process is carried out in any reaction cabin and the reaction gas environment is maintained, the gas environment management system can change the gas environment of the transfer cabin and the feeding and discharging cabin, and the gas environment management system can enable the transfer cabin and the feeding and discharging cabin to have two non-reaction gas environments. Through the arrangement, the production efficiency of the silicon carbide epitaxial furnace can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silicon carbide processing equipment, in particular to a gas environment management system and method and a silicon carbide epitaxial furnace. BACKGROUND

[0002] Silicon carbide, as the third generation of semiconductor materials, has a wide range of applications in new energy vehicles, charging piles, rail transit and other fields. The mainstream method for preparing a silicon carbide thin film layer is chemical vapor deposition (CVD). One or more substrates are arranged on a substrate holder inside a reactor, the substrate is heated to a desired temperature, and a reaction gas (such as a combination of a silicon source gas such as silane, a carbon source gas such as propane ethylene, and even a doping gas such as nitrogen) is passed through and heated on the heated substrate, and finally a silicon carbide thin film layer is deposited on the substrate. The silicon carbide thin film layer has the same crystal structure as the underlying substrate.

[0003] The preparation of a silicon carbide thin film layer requires the presence of a reaction gas, and a silicon carbide epitaxial furnace inevitably needs to manage the reaction gas and the external environmental gas of the silicon carbide epitaxial furnace. On the other hand, in the epitaxial process, the substrate needs to be loaded onto a graphite carrier disc. Due to the natural properties of graphite, it cannot be exposed to the external environmental gas of the silicon carbide epitaxial furnace at high temperatures. Therefore, the silicon carbide epitaxial furnace also introduces a protective gas (such as argon) to protect the carrier disc after the reaction gas is pumped out and the silicon carbide epitaxial deposition is terminated, until it cools down to a temperature suitable for being transported to the next process flow in the external gas environment of the silicon carbide epitaxial furnace. Therefore, the gas management inside the silicon carbide epitaxial furnace also needs to further manage the protective gas.

[0004] In the prior art, for example, patent application CN118186575A, a silicon carbide epitaxial furnace with only a single reaction chamber has only a single material channel, i.e. the substrate is transported into the silicon carbide epitaxial furnace by a feeding mechanism, loaded onto a carrier disc by a single loading mechanism, enters the single reaction chamber after epitaxial deposition, and is separated from the carrier disc by a single unloading mechanism, and finally leaves the silicon carbide epitaxial furnace by a discharging mechanism and enters the transport device. In between, each in-chamber of the substrate or the corresponding silicon carbide thin film layer needs to be sequentially pumped out of the external environmental gas of the epitaxial furnace, released from the reaction gas, pumped out of the reaction gas, released from the protective gas, pumped out of the protective gas, and released from the external environmental gas of the epitaxial furnace, to ensure that the substrate, the silicon carbide thin film layer or other supporting devices are always in the corresponding gas environment of the process.

[0005] With the increasing requirements for silicon carbide epitaxy process, the gas management of the single material channel becomes a bottleneck of the process efficiency: each of the above-mentioned gas environment management actions needs to be performed comprehensively and without exception for each substrate to be processed, and obviously any gas environment management action, especially the management action irrelevant to the reaction gas, means that the reaction chamber is not in production operation. Moreover, the unoptimized gas management often relies on manual operation and performs the same gas management action on all furnace chambers of the entire silicon carbide epitaxy furnace, thereby further reducing the production efficiency.

[0006] Therefore, how to design a gas environment management system of a silicon carbide epitaxy furnace to improve the production efficiency of a silicon carbide thin film layer is a problem to be solved by those skilled in the art. SUMMARY

[0007] The present application provides a gas environment management system, method and silicon carbide epitaxy furnace, aiming at solving the problem of low production efficiency of the silicon carbide epitaxy furnace caused by the serial process flow in the prior art.

[0008] In a first aspect, the embodiments of the present application provide a gas environment management system suitable for a silicon carbide epitaxy furnace. The gas environment management system is independently connected with a reaction chamber of the silicon carbide epitaxy furnace, a transfer chamber of the silicon carbide epitaxy furnace and a loading and unloading chamber of the silicon carbide epitaxy furnace, and independently controls the gas environment of the reaction chamber, the transfer chamber and the loading and unloading chamber. When a chemical vapor deposition process is performed in any of the reaction chambers and the reaction gas environment thereof is maintained, the gas environment management system can change the gas environment of the transfer chamber and the loading and unloading chamber. The gas environment management system can make the transfer chamber and the loading and unloading chamber both have two non-reaction gas environments, i.e., a protective gas environment and an external gas environment of the silicon carbide epitaxy furnace.

[0009] In a possible implementation, the gas environment management system includes a functional gas release subsystem and a gas extraction subsystem. The functional gas release subsystem has at least a reaction gas source and a protective gas source. The reaction gas source is connected to the reaction chamber through a pipeline, and the protective gas source is connected to the reaction chamber, the transfer chamber and the loading and unloading chamber through a pipeline. The pipeline between the reaction gas source and the reaction chamber, the pipeline between the reaction gas source and the transfer chamber, the pipeline between the reaction gas source and the loading and unloading chamber, the pipeline between the protective gas source and the reaction chamber, the pipeline between the protective gas source and the transfer chamber and the pipeline between the protective gas source and the loading and unloading chamber are all provided with independently controlled shut-off devices. The gas extraction subsystem has a vacuum pump connected to the reaction chamber, the transfer chamber and the loading and unloading chamber through a pipeline. The pipeline between the vacuum pump and the reaction chamber, the pipeline between the vacuum pump and the transfer chamber and the pipeline between the vacuum pump and the loading and unloading chamber are all provided with independently controlled adjusting devices.

[0010] In a possible implementation, the cutoff device of the functional gas releasing subsystem and the regulating device of the gas extraction subsystem can be opened simultaneously to maintain a reaction gas environment or a protective gas environment.

[0011] In a possible implementation, the gas environment management system further comprises a plurality of groups of air gauges, each of which is connected to the reaction chamber, the transfer chamber and the loading and unloading chamber through a pipeline. Each group of air gauges comprises a first air gauge and a second air gauge with a pressure measuring range smaller than that of the first air gauge. The second air gauge is provided with a cutoff device. When the air pressure in the reaction chamber, the transfer chamber and the loading and unloading chamber is within the pressure measuring range of the second air gauge, the cutoff device is opened.

[0012] In a possible implementation, the transfer chamber is provided with a plug valve between the reaction chamber and the loading and unloading chamber, and the loading and unloading chamber is provided with a plug valve between the furnace environment and the outside environment. When the plug valve is opened, the gas environment on both sides of the plug valve tends to be the same.

[0013] In a possible implementation, the connection mode of the gas environment management system and the separate chamber of the silicon carbide epitaxial furnace is the same as the connection mode of the gas environment management system and the reaction chamber. The connection mode of the transfer chamber and the separate chamber is the same as the connection mode of the transfer chamber and the reaction chamber.

[0014] In a possible implementation, each regulating device comprises a regulating valve and a cutoff valve. The regulating valves of the plurality of regulating devices are connected to a vacuum pump. The cutoff valves of the plurality of regulating devices are independently connected to the reaction chamber, the transfer chamber and the loading and unloading chamber, respectively.

[0015] In a second aspect, the embodiments of the present application provide a gas environment management method applied to the above-mentioned gas environment management system. The method comprises the following steps: when a chemical vapor deposition process is performed in the reaction chamber of a silicon carbide epitaxial furnace, maintaining a reaction gas environment in the reaction chamber through the gas environment management system; connecting the loading and unloading chamber to the furnace environment outside the silicon carbide epitaxial furnace, so that the loading and unloading chamber is in the gas environment outside the silicon carbide epitaxial furnace, and placing a substrate in the loading and unloading chamber; separating the loading and unloading chamber from the furnace environment outside the silicon carbide epitaxial furnace, and vacuumizing the loading and unloading chamber; filling the loading and unloading chamber with a protective gas until the loading and unloading chamber is in a protective gas environment; maintaining a protective gas environment in the transfer chamber, connecting the loading and unloading chamber to the transfer chamber, and transferring the substrate into the transfer chamber; after the completion of a previous chemical vapor deposition process in the reaction chamber, placing the substrate in the reaction chamber for a next chemical vapor deposition process.

[0016] In a possible implementation, the gas environment management system comprises a vacuum pump and a plurality of regulating devices, each of the regulating devices comprises a regulating valve and a stop valve, the regulating valves of the plurality of regulating devices are connected to the vacuum pump, and the stop valves of the plurality of regulating devices are independently connected to the reaction chamber, the transfer chamber and the loading and unloading chamber respectively; the process of vacuumizing the loading and unloading chamber is as follows: the loading and unloading chamber is controlled to be in a closed state, and the stop valve is opened, and the regulating valve is opened at an opening degree of 1% per second until the loading and unloading chamber reaches a first vacuum degree; the transfer chamber is controlled to be in a closed state, and the regulating valve is opened at an opening degree of 5% per second until the regulating valve is fully opened, and the loading and unloading chamber is vacuumized when the loading and unloading chamber reaches a second vacuum degree, and the second vacuum degree is greater than the first vacuum degree.

[0017] In a third aspect, the embodiments of the present application provide a silicon carbide epitaxial furnace, comprising a reaction chamber, a loading and unloading chamber, a transfer chamber and the above-mentioned gas environment management system, the reaction chamber can independently perform a chemical vapor deposition process; the loading and unloading chamber can be docked with a carrier outside the furnace to receive a substrate from the carrier or deliver an epitaxial wafer to the carrier; the transfer chamber can communicate the reaction chamber and the loading and unloading chamber; and the gas environment management system can perform the above-mentioned gas environment management method.

[0018] The above-mentioned gas environment management system, method and silicon carbide epitaxial furnace can enable the gas environment management system to independently control the gas environment of each furnace chamber, so that when the reaction chamber is in a working state, other furnace chambers can be simultaneously worked to reduce the working time of other furnace chambers, thereby improving the working efficiency of the silicon carbide epitaxial furnace. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The structure block diagram of the silicon carbide epitaxial furnace provided by the embodiments of the present application is provided.

[0020] Figure 2 The structure block diagram of the silicon carbide epitaxial furnace and the gas environment management system provided by the embodiments of the present application is provided.

[0021] Figure 3 The structure block diagram of the functional gas release subsystem of the gas environment management system provided by the embodiments of the present application is provided.

[0022] Figure 4 The detailed structure diagram of the silicon carbide epitaxial furnace and the gas environment management system provided by the embodiments of the present application is provided.

[0023] Figure 5 The structure block diagram of the gas management system control component of the gas environment management system provided by the embodiments of the present application is provided.

[0024] Figure 6 The flowchart of the gas environment management method provided by the embodiments of the present application is provided.

[0025] Figure 7The specific flow chart of step T3 of the gas environment management method provided by the embodiment of the present application.

[0026] Figure 8 The logic diagram of step T3 of the gas environment management method provided by the embodiment of the present application.

[0027] Figure 9 The furnace chamber pressure control logic diagram of the gas environment management method provided by the embodiment of the present application.

[0028] Figure 10 The furnace chamber backfilling logic diagram of the gas environment management method provided by the embodiment of the present application.

[0029] Illustration: 1, silicon carbide epitaxial furnace; 10, furnace chamber; 110, reaction chamber; 110A, first reaction chamber; 110B, second reaction chamber; 120, separation chamber; 120A, first separation chamber; 120B, second separation chamber; 130, transfer chamber; 140, loading and unloading chamber; 150, plug valve; 160, carrier plate; 170, first robot; 2, second robot; 3, carrier; 20, gas environment management system; 210, gas management system control assembly; 211, first air pressure gauge; 212, second air pressure gauge; 213, third stop valve; 214, controller; 220, functional gas release subsystem; 221, first gas source; 222, second gas source; 223, third gas source; 22, stop device; 224, first stop valve; 225, flow meter; 226, fifth stop valve; 230, gas extraction subsystem; 231, vacuum pump; 232, adjusting device; 2321, adjusting valve; 2322, second stop valve; 234, gas recovery terminal. DETAILED DESCRIPTION

[0030] In order to make the people in the art better understand the scheme of the present application, the technical scheme in the specific embodiment of the present application will be described clearly and completely below by combining the drawings in the embodiment of the present application.

[0031] It should be noted that the terms "first", "second" and similar terms used in the specification and claims of the application do not necessarily mean any order, number or importance, but are only used to distinguish different components. Similarly, the terms "one" or "a" or similar terms do not mean a quantity limitation, but mean the presence of at least one. "Multiple" or "several" means at least two. Unless otherwise indicated, the terms "front", "back", "left", "right", "lower" and / or "upper" and similar terms are used for convenience only and are not intended to be limiting to a particular position or spatial orientation. The terms "include" or "contain" or similar terms mean that the elements or objects appearing before the "include" or "contain" are encompassed by the elements or objects appearing after the "include" or "contain" and their equivalents, and do not exclude other elements or objects. The terms "connected" or "connected" or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0032] The singular forms "a", "said" and "the" used in the specification and claims of the application can also include one or more, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which means that A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural.

[0033] The embodiments of the present application provide a gas environment management system 20, a method and a silicon carbide epitaxial furnace 1, aiming to break through the efficiency bottleneck caused by the gas environment control along the material channel in the prior art silicon carbide epitaxial furnace.

[0034] As shown in Figure 1 The silicon carbide epitaxial furnace 1 provided by the embodiments of the present application includes a plurality of furnace chambers 10, plug valves 150, carrier plates 160 and first mechanical arms 170. Specifically, the furnace chamber 10 includes a reaction chamber 110, a separation chamber 120, a transfer chamber 130 and a feeding and discharging chamber 140. The reaction chamber 110, the separation chamber 120 and the feeding and discharging chamber 140 are arranged around the transfer chamber 130, and the plug valves 150 are arranged between the transfer chamber 130 and each of the reaction chamber 110, the separation chamber 120 and the feeding and discharging chamber 140. When the corresponding plug valve 150 is opened, the transfer chamber 130 is communicated with the reaction chamber 110, the separation chamber 120 and the feeding and discharging chamber 140. For example, when the plug valve 150 between the transfer chamber 130 and the reaction chamber 110 is opened, the transfer chamber 130 and the reaction chamber 110 are communicated.

[0035] The reaction chamber 110 can independently perform a chemical vapor deposition process, and is suitable for accommodating a silicon carbide substrate (not shown), a carrier plate 160 and a reaction gas, and can be heated to a chemical vapor deposition process temperature.

[0036] The separation chamber 120 is capable of loading the silicon carbide substrate to the carrier tray 160 or unloading the silicon carbide epitaxial wafer (not shown) from the carrier tray 160.

[0037] The loading and unloading chamber 140 is capable of receiving the substrate fed into the silicon carbide epitaxial furnace 1 or the epitaxial wafer discharged from the silicon carbide epitaxial furnace 1. Further, the loading and unloading chamber 140 is docked with the carrier 3 located outside the furnace, receiving the substrate grabbed from the carrier 3 by the second robot 2 arranged outside the silicon carbide epitaxial furnace 1 or the epitaxial wafer grabbed from the same by the second robot 2 to the carrier 3.

[0038] The flapper valve 150 can be controlled by an electric signal to be quickly opened or closed, i.e. to provide a gas passage between the corresponding two furnace chambers 10 when opened or to close the gas passage between the corresponding two furnace chambers 10 when closed. That is, the flapper valve 150 realizes the gas environment on both sides of the flapper valve 150 to be similar when opened.

[0039] In some embodiments, the reaction chamber 110 includes at least a first reaction chamber 110A and a second reaction chamber 110B, and the separation chamber 120 includes at least a first separation chamber 120A and a second separation chamber 120B. That is, the reaction chamber 110 and the separation chamber 120 are both provided with two. It can be understood that the number of the reaction chamber 110 and the separation chamber 120 is not limited in the present application.

[0040] For example, the reaction chamber 110 and the separation chamber 120 are both provided with two.

[0041] The first reaction chamber 110A, the second reaction chamber 110B, the first separation chamber 120A, the second separation chamber 120B and the loading and unloading chamber 140 are arranged around the transfer chamber 130, and the flapper valve 150 is arranged between the transfer chamber and each of the first reaction chamber 110A, the second reaction chamber 110B, the first separation chamber 120A, the second separation chamber 120B and the loading and unloading chamber 140.

[0042] Therefore, the silicon carbide epitaxial furnace 1 forms a plurality of material passages. If the material in the material passage is a substrate, it can pass from the loading and unloading chamber 140 to the first reaction chamber 110A through the first separation chamber 120A or the second separation chamber 120B, or to the second reaction chamber 110B through the first separation chamber 120A or the second separation chamber 120B; if the material in the material passage is an epitaxial wafer, it can pass from the first reaction chamber 110A to the loading and unloading chamber 140 through the first separation chamber 120A or the second separation chamber 120B, or from the second reaction chamber 110B to the loading and unloading chamber 140 through the first separation chamber 120A or the second separation chamber 120B.

[0043] It should be noted that in the present application, the separation cabin 120 can not be provided, i.e., the substrate directly enters the reaction cabin 110 from the loading and unloading cabin 140 through the transfer cabin 130, or the epitaxial wafer directly enters the loading and unloading cabin 140 from the reaction cabin 110 through the transfer cabin 130. Therefore, the present application does not limit whether the separation cabin 120 is provided or not.

[0044] As shown in Figure 1 and Figure 2 In order to cooperate with the multi-material passage setting of the silicon carbide epitaxial furnace 1 and fully exert its improvement on production efficiency, the present application further provides a gas environment management system 20 of the silicon carbide reaction furnace 1.

[0045] In the case where the separation cabin 120 is not provided, the gas environment management system 20 is independently connected with the reaction cabin 110, the gas environment management system 20 is independently connected with the transfer cabin 130, and the gas environment management system 20 is independently connected with the loading and unloading cabin 140, and the gas environment management system 20 independently controls the gas environment of each furnace cabin 10, i.e., the gas environment management system 20 can independently control the gas environment of the reaction cabin 110, the transfer cabin 130 and the loading and unloading cabin 140.

[0046] When the chemical vapor deposition process is carried out in any reaction cabin 110 and the reaction gas environment thereof is maintained, the gas environment management system 20 can change the gas environment of the transfer cabin 130 and the loading and unloading cabin 140, and the gas environment management system 20 can make the transfer cabin 130 and the loading and unloading cabin 140 both have two non-reaction gas environments, i.e., the protective gas environment and the external gas environment of the silicon carbide epitaxial furnace 1. Through the above setting, the gas environment management system 20 can independently control the gas environment of each furnace cabin 10, so that when the reaction cabin 110 is in a working state, other furnace cabins 10 can work synchronously to reduce the working time of other furnace cabins 10 and improve the working efficiency of the silicon carbide epitaxial furnace 1.

[0047] In the case where the separation cabin 120 is provided, the connection mode of the gas environment management system 20 and the separation cabin 120 is the same as the connection mode of the gas environment management system 20 and the reaction cabin 110, which will not be described here.

[0048] It should be noted that the present application takes the reaction cabin 110 and the separation cabin 120 both provided with two as an example for description.

[0049] At the first time, the first reaction chamber 110A is maintained with the reaction gas at the required low pressure for the chemical vapor deposition to continue, the second reaction chamber 110B, the first separation chamber 120A, the second separation chamber 120B and the transfer chamber 130 are maintained with the protective gas at the required pressure, and the loading and unloading chamber 140 is filled with the external environment gas of the silicon carbide epitaxial furnace 1 at the external environment pressure.

[0050] The first time refers to the moment when the chemical vapor deposition process for the substrate is being performed in the first reaction chamber 110A, the epitaxial wafer is just obtained from the chemical vapor deposition reaction in the second reaction chamber 110B, the first separation chamber 120A is placed with the loaded substrate carrier 160, the second separation chamber 120B is empty, the loading and unloading chamber 140 is empty, the carrier 3 has been disconnected from the loading and unloading chamber 140, and the carrier 3 is about to go to the next process.

[0051] At the second time, the first reaction chamber 110A and the second reaction chamber 110B are maintained with the reaction gas at the required low pressure for the chemical vapor deposition to continue, the first separation chamber 120A, the second separation chamber 120B, the transfer chamber 130 and the loading and unloading chamber 140 are maintained with the protective gas at the required pressure.

[0052] The second time refers to the moment when the chemical vapor deposition process for the substrate is being performed in the first reaction chamber 110A and the second reaction chamber 110B, the first separation chamber 120A and the second separation chamber 120B are placed with the loaded epitaxial wafer carrier 160, the loading and unloading chamber 140 is placed with the substrate, and the plug valve 150 between the loading and unloading chamber 140 and the transfer chamber 130 is opened.

[0053] In order to achieve the above two gas environments, the first reaction chamber 110A, the second reaction chamber 110B, the first separation chamber 120A, the second separation chamber 120B, the transfer chamber 130 and the loading and unloading chamber 140 of the silicon carbide epitaxial furnace 1 provided in the embodiments of the present application, i.e., each furnace chamber 10 except for the explicitly described parts, are covered by airtight walls, and the plug valve 150 is provided between each furnace chamber 10, which is also airtight when closed.

[0054] As shown in FIGS. 1, 2 and 3, the silicon carbide epitaxial furnace 1 provided in the embodiments of the present application includes a plurality of furnace chambers 10, a carrier 3 and a gas environment management system 20. Figure 3 and Figure 4 As shown in FIGS. 1, 2 and 3, the silicon carbide epitaxial furnace 1 provided in the embodiments of the present application includes a plurality of furnace chambers 10, a carrier 3 and a gas environment management system 20.

[0055] In some embodiments, the first gas source 221 provides a silicon source gas, for example, silane, the second gas source 222 provides a carbon source gas, for example, ethylene, and the third gas source 223 provides a protective gas, for example, argon.

[0056] Those skilled in the art can add more gas sources to the embodiments of the present application without creative work, for example, a fourth gas source providing a doping gas, for example, nitrogen. The embodiments of the present application will not be described here.

[0057] In the embodiments of the present application, the silicon source gas, the carbon source gas, and the doping gas are all regarded as reaction gases, i.e., the functional gas releasing subsystem 220 at least has a reaction gas source and a protective gas source, for example, argon.

[0058] The first gas source 221 and the second gas source 222 (i.e., the reaction gas source) are connected to the first reaction chamber 110A and the second reaction chamber 110B, respectively, through pipes. The third gas source 223 (i.e., the protective gas source) is connected to each furnace chamber 10 through pipes, i.e., the third gas source 223 (i.e., the protective gas source) is connected to the reaction chamber 110, the transfer chamber 130, and the charging and discharging chamber 140 through pipes.

[0059] Each pipe connecting any gas source to any furnace chamber 10 is provided with an independently controlled cutoff device 22. That is, the pipes connecting the reaction gas source to the reaction chamber 110, the pipes connecting the reaction gas source to the transfer chamber 130, the pipes connecting the reaction gas source to the charging and discharging chamber 140, the pipes connecting the protective gas source to the reaction chamber 110, the pipes connecting the protective gas source to the transfer chamber 130, and the pipes connecting the protective gas source to the charging and discharging chamber 140 are all provided with independently controlled cutoff devices 22.

[0060] In some embodiments, each pipe connecting any gas source to any furnace chamber 10 is provided with a first cutoff valve 224, a flow meter 225, and a fifth cutoff valve 226 in sequence, i.e., the cutoff device 22 includes the first cutoff valve 224, the flow meter 225, and the fifth cutoff valve 226. The first cutoff valve 224 and the fifth cutoff valve 226 are both preferably diaphragm valves, which can be controlled by an electric signal to open and close quickly.

[0061] The opening and closing of the first cutoff valve 224 is equivalent to starting or stopping the release of each functional gas. The opening of the fifth cutoff valve 226 is equivalent to starting to receive the corresponding functional gas, and the closing of the fifth cutoff valve 226 is equivalent to closing the gas inlet of the corresponding furnace chamber 10.

[0062] For example, as shown in FIG. 1, the first cutoff valve 224 is opened to release the functional gas, and the fifth cutoff valve 226 is closed to close the gas inlet of the corresponding furnace chamber 10. Figure 4As shown, as an implementation, the gas environment management system 20 comprises a gas evacuation subsystem 230, which comprises a vacuum pump 231, a regulating device 232, and a gas recovery terminal 234. The vacuum pump 231 and the gas recovery terminal 234 work in cooperation, and the gas recovery terminal 234 recovers the gas evacuated by the vacuum pump 231, which is connected to each furnace chamber 10 through a pipeline. That is, the vacuum pump 231 is connected to the reaction chamber 110, the transfer chamber 130, and the charging and discharging chamber 140 through pipelines, respectively.

[0063] In some embodiments, each of the pipelines between the vacuum pump 231 and each furnace chamber 10 is provided with an independently controlled regulating device 232. That is, each of the pipelines between the vacuum pump 231 and the reaction chamber 110, the transfer chamber 130, and the charging and discharging chamber 140 is provided with an independently controlled regulating device 232. The regulating device 232 is adapted to open or close the gas passage between the vacuum pump 231 and each furnace chamber 10.

[0064] Specifically, the regulating device 232 comprises a regulating valve 2321 and a second stop valve 2322. The regulating valve 2321 is arranged at the end of the pipeline close to the vacuum pump 231, and adjusts the gas evacuation capacity of the vacuum pump 231 to each furnace chamber 10 by opening, closing, and partially closing. The regulating valve is preferably a butterfly valve. The pipeline between the vacuum pump 231 and each furnace chamber 10 is also provided with a second stop valve 2322 at the end close to each furnace chamber 10. The second stop valve 2322 is preferably an angular valve, which can be controlled by an electrical signal to quickly open and close, that is, to start or stop the gas evacuation of the vacuum pump 231 to the corresponding furnace chamber 10, and to close the gas outlet of the corresponding furnace chamber 10 when closed.

[0065] In the present embodiment, the regulating valves 2321 of the plurality of regulating devices 232 are connected to the vacuum pump 231, and the second stop valves 2322 of the plurality of regulating devices 232 are independently connected to the reaction chamber 110, the transfer chamber 130, and the charging and discharging chamber 140, respectively. It should be noted that the regulating valve 2321 and the second stop valve 2322 of each regulating device 232 are connected through a pipeline. The plurality of regulating valves 2321 are also connected to the vacuum pump 231 through a pipeline. The plurality of second stop valves 2322 are independently connected to the reaction chamber 110, the transfer chamber 130, and the charging and discharging chamber 140 through pipelines, respectively.

[0066] In some embodiments, the stop device 22 of the functional gas releasing subsystem 220 and the regulating device 232 of the gas evacuation subsystem 230 can be opened at the same time to maintain the reaction gas environment or the protective gas environment.

[0067] As Figure 5As shown, the gas environment management system 20 of the silicon carbide epitaxial furnace 1 of the embodiment of the present application further comprises a gas management system control assembly 210, which comprises a first air pressure gauge 211, a second air pressure gauge 212, a third stop valve 213 and a controller 214. The first air pressure gauge 211 and the second air pressure gauge 212 are combined as an air pressure gauge group. It should be noted that the air pressure gauge group in the present application is provided with multiple air pressure gauges. The multiple air pressure gauges are respectively connected to the reaction chamber 110, the transfer chamber 130 and the charging and discharging chamber 140 through pipelines. That is, each furnace chamber 10 is provided with one first air pressure gauge 211 and one second air pressure gauge 212.

[0068] The first air pressure gauge 211 preferably has a relatively high pressure measurement range, such as 1k~133kPa, and is connected to or directly exposed to the gas environment in the furnace chamber 10 through a pipeline.

[0069] The second air pressure gauge 212 preferably has a relatively low pressure measurement range, such as 1~1kPa, that is, the measurement range of the second air pressure gauge 212 is smaller than that of the first air pressure gauge 211. The second air pressure gauge 212 is connected to the gas environment in the furnace chamber 10 through a pipeline, and the pipeline between the second air pressure gauge 212 and the furnace chamber 10 is provided with a third stop valve 213, that is, the second air pressure gauge 212 is provided with a stop device. The third stop valve 213 is only opened when the air pressure in the furnace chamber 10 is within the pressure measurement range of the second air pressure gauge 212, that is, when the air pressure in the reaction chamber 110, the transfer chamber 130 and the charging and discharging chamber 140 is within the pressure measurement range of the second air pressure gauge 212, the third stop valve 213 is opened, thereby controlling the timing of exposing the second air pressure gauge 212 to the measured gas environment, so as to avoid damaging the second air pressure gauge 212 when the measured gas environment is outside the pressure measurement range of the second air pressure gauge 212.

[0070] The controller 214 is connected to the first air pressure gauge 211, the second air pressure gauge 212 and the third stop valve 213 through wired or wireless electrical signals, respectively, to receive the measured values of the first air pressure gauge 211 and the second air pressure gauge 212 and / or control the opening and closing of the third stop valve 213.

[0071] In the present embodiment, the controller 214 is further connected to the flow meter 225, the fifth stop valve 226, the regulating valve 2321, the second stop valve 2322 and the plug valve 150 through wired or wireless electrical signals, respectively, to receive the corresponding measured values or control the opening, closing and / or partial closing of the valves.

[0072] Based on the silicon carbide epitaxial furnace 1 and the gas environment management system 20 thereof, during the process of transferring the substrate from the carrier 3 through the second separation cabin 120B (or the first separation cabin 120A, the same below) to the first reaction cabin 110A (or the second reaction cabin 110B, the same below), the gas environment of each furnace cabin 10 can be achieved as follows: In step S100, it is confirmed that the carrier 3 is docked with the loading and unloading cabin 140, it is confirmed that all plug valves 150 between the furnace cabins 10 are closed, it is confirmed that the current gas environment of each furnace cabin 10 is maintained, and in particular, it is confirmed that the low-pressure protective gas environment of the transfer cabin 130 and the second separation cabin 120B is maintained. The maintenance of the protective gas environment at least includes two ways of completely closing the corresponding furnace cabin 10 and continuously and balancedly filling or removing the protective gas. If the above confirmations are completed, the program starts. In step S101, the second stop valve 2322 of the loading and unloading cabin 140 is opened, the gas removal capability of the vacuum pump 231 to the loading and unloading cabin 140 is activated, and the gas (for example, the protective gas left in the last process) in the loading and unloading cabin 140 is removed to the gas recovery terminal 234. If necessary, the gas removal capability of the vacuum pump 231 to the loading and unloading cabin 140 is increased or decreased through the corresponding adjusting valve 2321, and the third stop valve 213 is opened to confirm that the gas pressure gradually reaches the second vacuum degree. In step S102, the second stop valve 2322 of the loading and unloading cabin 140 is closed, the gas removal capability of the vacuum pump 231 to the loading and unloading cabin 140 is cut off, the plug valve 150 between the loading and unloading cabin 140 and the external environment of the furnace is opened, and the external environment gas of the silicon carbide epitaxial furnace is filled into the loading and unloading cabin 140. In step S103, when the gas pressure of the external environment of the silicon carbide epitaxial furnace is substantially reached, the plug valve 150 between the loading and unloading cabin 140 and the external environment of the furnace is closed, the plug valve 150 between the loading and unloading cabin 140 and the carrier 3 is opened, the substrate is grabbed from the carrier 3 by using the second mechanical arm 2, and the substrate is placed into the loading and unloading cabin 140. In step S104, the plug valve 150 between the loading and unloading cabin 140 and the carrier 3 is closed, the second stop valve 2322 of the loading and unloading cabin 140 is opened, the gas (i.e., the external environment gas of the silicon carbide epitaxial furnace left in step 103) in the loading and unloading cabin 140 is removed to the gas recovery terminal 234 by using the vacuum pump 231, if necessary, the gas removal capability of the vacuum pump 231 to the loading and unloading cabin 140 is increased or decreased through the corresponding adjusting valve 2321, and the third stop valve 213 is opened to confirm that the gas pressure gradually reaches the second vacuum degree. In step S105, the second stop valve 2322 of the loading and unloading cabin 140 is closed, the first stop valve 224 and the fifth stop valve 226 between the loading and unloading cabin 140 and the third gas source 223 are opened, the protective gas is filled into the loading and unloading cabin 140 from the third gas source 223 to a low pressure, and if necessary, the third stop valve 213 is opened to confirm the gas pressure of the protective gas. Step S106, the first stop valve 224 of the loading and unloading cabin 140 is closed, the plug valve 150 between the transfer cabin 130 and the loading and unloading cabin 140 is opened, the plug valve 150 between the transfer cabin 130 and the second separation cabin 120B is opened, in a typical case, the gas in the second separation cabin 120B is the protective gas left by the previous process, and the gas environment of the transfer cabin 130, the second separation cabin 120B and the loading and unloading cabin 140 is converged; Step S107, the plug valve 150 between the transfer cabin 130 and the loading and unloading cabin 140 is closed, the plug valve 150 between the transfer cabin 130 and the second separation cabin 120B is closed, the plug valve 150 between the transfer cabin 130 and the loading and unloading cabin 140 is opened, the plug valve 150 between the transfer cabin 130 and the second separation cabin 120B is opened, the first manipulator 170 is used to pick up the substrate and place it into the second separation cabin 120B and load it to the carrier 160, and the plug valve 150 between the transfer cabin 130 and the loading and unloading cabin 140 is closed; Step S108, in a typical case, the gas in the first reaction cabin 110A is the protective gas left by the previous process, if so, the plug valve 150 between the transfer cabin 130 and the first reaction cabin 110A is opened, and the gas environment between the transfer cabin 130 and the first reaction cabin 110A is converged; Step S109, the plug valve 150 between the transfer cabin 130 and the first reaction cabin 110A is closed, the plug valve 150 between the transfer cabin 130 and the first reaction cabin 110A is opened, the first manipulator 170 is used to pick up the substrate and the carrier 160 from the second separation cabin 110B and place them into the first reaction cabin 110A, the plug valve 150 between the transfer cabin 130 and the second separation cabin 120B is closed, and the plug valve 150 between the transfer cabin 130 and the first reaction cabin 110A is closed; Step S110, the second stop valve 2322 of the first reaction cabin 110A is opened, the gas (the protective gas left by step S109) in the first reaction cabin 110A is pumped to the gas recovery terminal 234, if necessary, the gas pumping capacity of the vacuum pump 231 to the first reaction cabin 110A is increased or decreased by the corresponding adjusting valve 2321, and the corresponding third stop valve 213 is opened to confirm that the gas pressure gradually reaches the second vacuum degree; Step S111: close the second stop valve 2322 of the reaction chamber 110, open the first stop valve 224 between the first reaction chamber 110A and the first gas source 221 and the second gas source 222, respectively, so that the first gas source 221 and the second gas source 222 continuously fill the first reaction chamber 110A with reaction gas, open the second stop valve 2322 of the first reaction chamber 110A, and continuously pump the reaction gas tail gas from the first reaction chamber 110A to the gas recovery terminal 234. If necessary, open the corresponding third stop valve 213 to confirm the reaction gas pressure in the first reaction chamber 110A, and increase or decrease the exhaust gas pumping capacity of the vacuum pump 231 for the first reaction chamber 110A through the corresponding regulating valve 2321 to maintain a low-pressure reaction gas environment; and In step S112, the gas management procedure ends and the epitaxial deposition on the substrate begins.

[0073] It should be noted that when the chemical vapor deposition process is carried out in the reaction chamber 110 of the silicon carbide epitaxial furnace 1, the gas environment management system 20 can maintain the reaction gas environment in the reaction chamber 110, and at the same time perform at least one of the following operations on at least one other furnace chamber 10 in the silicon carbide epitaxial furnace 1: evacuate the gas in the chamber to vacuum and fill the chamber with protective gas. In addition, when the chemical vapor deposition process is carried out in the reaction chamber 110 of the silicon carbide epitaxial furnace 1, the upper and lower material chambers 140 can be connected to the external environment through the plug valve 150. Therefore, the gas environment management method of the present application can, while maintaining the reaction gas environment in the reaction chamber 110, successively perform the operations of connecting the upper and lower material chambers 140 with the external environment and the operations of filling the upper and lower material chambers 140 with protective gas, so that the next substrate can enter the reaction chamber 110 after the previous substrate forms an epitaxial wafer, thereby improving the production efficiency of epitaxial wafers.

[0074] like Figure 6 As shown, as an implementation method, the gas environment management method of the present application includes the following steps: T1, when a chemical vapor deposition process is performed in the reaction chamber 110 of the silicon carbide epitaxial furnace 1, the reaction gas environment in the reaction chamber 110 is maintained by the gas environment management system 20; T2, connecting the upper and lower material cabins 140 with the environment outside the furnace, the upper and lower material cabins 140 are in the external gas environment of the silicon carbide epitaxial furnace 1, and the substrates are placed in the upper and lower material cabins 140; T3, separating the upper and lower material cabins 140 from the environment outside the furnace and evacuating the upper and lower material cabins 140; T4, filling the upper and lower material cabins 140 with protective gas until the upper and lower material cabins 140 are in a protective gas environment; T5, maintaining the protective gas environment of the transfer chamber 130, connecting the upper and lower chambers 140 with the transfer chamber 130, and transferring the substrate into the transfer chamber 130; T6, after the previous chemical vapor deposition process in the reaction chamber 110 is completed, the substrate is placed in the reaction chamber 110 to perform the next chemical vapor deposition process.

[0075] Through the above setting, the gas environment management method of the present application can perform the operation of communicating the upper and lower loading chambers 140 with the external environment and the operation of filling the protective gas into the upper and lower loading chambers 140 in sequence while maintaining the reaction gas environment in the reaction chamber 110, so that the next substrate can enter the reaction chamber 110 after the previous substrate forms an epitaxial wafer, thereby improving the production efficiency of the epitaxial wafer.

[0076] As shown in Figure 7 , as an implementation manner, the process of vacuumizing the upper and lower loading chambers 140 is as follows: G1, control the upper and lower loading chambers 140 to be in a closed state, and open the second stop valve 2322, open the regulating valve 2321 by 1% per second until the upper and lower loading chambers 140 reach the first vacuum degree; G2, control the transfer chamber 130 to be in a closed state, open the regulating valve 2321 by 5% per second until the regulating valve 2321 is fully opened, and the upper and lower loading chambers 140 complete vacuumizing when the upper and lower loading chambers 140 reach the second vacuum degree. The second vacuum degree is greater than the first vacuum degree. Through the above setting, the vacuumizing process of the upper and lower loading chambers 140 can be stable and efficient, and the equipment can be protected from pressure impact.

[0077] In step G1, controlling the upper and lower loading chambers 140 to be in a closed state means closing the plug valve 150 and the stop device 22 connected to the upper and lower loading chambers 140.

[0078] In step G2, controlling the transfer chamber 130 to be in a closed state means closing the plug valve 150 connected to the transfer chamber 130.

[0079] As shown in Figure 8 , specifically, the specific operation process of vacuumizing the upper and lower loading chambers 140 is as follows: G11, determine whether the upper and lower loading chambers 140 are closed, if yes, execute step G12; if no, execute step G13; G12, close the stop device 22 connected to the upper and lower loading chambers 140, and open the second stop valve 2322; G13, close the plug valve 150 connected to the upper and lower loading chambers 140; G14, determine whether the upper and lower loading chambers 140 reach the first vacuum degree, if yes, execute step G21, if no, execute step G22; G21, close the plug valve 150 connected to the transfer chamber 130; G22, open the regulating valve 2321 by 1% per second until the first vacuum degree is reached in the loading and unloading cabin 140; G23, determine whether the second vacuum degree is reached in the loading and unloading cabin 140, if yes, execute step G24, if no, execute step G25; G24, end the vacuumizing; G25, open the regulating valve 2321 by 5% per second until the second vacuum degree is reached in the loading and unloading cabin 140.

[0080] When the chemical vapor deposition process is completed, the epitaxial wafer is obtained on the substrate, and in the process of transferring the epitaxial wafer from the first reaction cabin 110A (or the second reaction cabin 110B, the same below) to the first separation cabin 120A (or the second separation cabin 120B, the same below), the gas environment of each furnace cabin 10 can be achieved as follows: Step S200, confirm that the corresponding first stop valve 224 and second stop valve 2322 of the first reaction cabin 110A are opened, all the plug valves 150 are closed, the first reaction cabin 110A maintains a low-pressure reaction gas environment, the transfer cabin 130 and the first separation cabin 120A maintain a low-pressure protective gas environment, the epitaxial deposition of the substrate is just completed, and the maintenance of the protective gas environment at least includes two ways of completely sealing the corresponding furnace cabin 10 and continuously balancing the filling or removal of the protective gas, and the program starts after the above confirmation is completed; Step S201, close the first stop valve 224 of the first reaction cabin 110A, so that the vacuum pump 231 removes the reaction gas in the first reaction cabin 110A to the gas recovery terminal 234, if necessary, the gas removal capacity of the vacuum pump 231 to the first reaction cabin 110A is increased or decreased by the corresponding regulating valve 2321, and the corresponding third stop valve 213 is opened to confirm that the gas pressure gradually reaches the second vacuum degree; Step S202, close the second stop valve 2322 of the first reaction cabin 110A, open the first stop valve 224 between the first reaction cabin 110A and the third gas source 223, so that the third gas source 223 fills the protective gas into the first reaction cabin 110A to a low pressure, in addition to the reaction gas in the first reaction cabin 110A to the gas recovery terminal 234, if necessary, the corresponding third stop valve 213 is opened to confirm the gas pressure of the protective gas; Step S203, close the first stop valve 224 of the first reaction cabin 110A, open the plug valve 150 between the transfer cabin 130 and the first reaction cabin 110A, and open the plug valve 150 between the transfer cabin 130 and the first separation cabin 120A, so that the transfer cabin 130, the first reaction cabin 110A and the first separation cabin 120A realize the convergence of the gas environment; Step S204, closing the plug valve 150 between the transfer chamber 130 and the first reaction chamber 110A, closing the plug valve 150 between the transfer chamber 130 and the first separation chamber 120A, opening the plug valve 150 between the transfer chamber 130 and the first reaction chamber 110A, opening the plug valve 150 between the transfer chamber 130 and the first separation chamber 120A, using the first mechanical arm 170 to pick up the epitaxial wafer and the carrier 160 from the first reaction chamber 110A and put them into the first separation chamber 120A, closing the plug valve 150 between the transfer chamber 130 and the first reaction chamber 110A; Step S205, closing the plug valve 150 between the transfer chamber 130 and the first separation chamber 120A; and Step S206, the program ends.

[0081] Through the above arrangement, when the chemical vapor deposition process is performed in the reaction chamber 110 of the silicon carbide epitaxial furnace 1, the reaction gas environment in the reaction chamber 110 is maintained, and at least one of the following operations is performed on at least one other functional furnace chamber 10 in the silicon carbide epitaxial furnace 1: evacuating the gas in the chamber to vacuum, filling the chamber with protective gas, and connecting the chamber with the external environment.

[0082] During the transfer of the epitaxial wafer from the first separation chamber 120A (or the second separation chamber 120B, the same below) to the carrier 3, the gas environment of each furnace chamber 10 can be achieved as follows: Step S300, confirming that the transfer chamber 130, the first separation chamber 120A, and the loading and unloading chamber 140 maintain a low-pressure protective gas environment, and all plug valves 150 are closed, the maintenance of the protective gas environment at least includes two ways of completely sealing the corresponding furnace chamber 10 and continuously and balancedly filling or evacuating the protective gas, and after the above confirmation is completed, the program starts; Step S301, opening the plug valve 150 between the transfer chamber 130 and the first separation chamber 120A, and opening the plug valve 150 between the transfer chamber 130 and the loading and unloading chamber 140, so that the transfer chamber 130, the loading and unloading chamber 140, and the first separation chamber 120A achieve gas environment convergence; Step S302, closing the plug valve 150 between the transfer chamber 130 and the first separation chamber 120A, closing the plug valve 150 between the transfer chamber 130 and the loading and unloading chamber 140, opening the plug valve 150 between the transfer chamber 130 and the first separation chamber 120A, opening the plug valve 150 between the transfer chamber 130 and the loading and unloading chamber 140, using the first mechanical arm 170 to unload the epitaxial wafer from the carrier 160 and put the epitaxial wafer into the loading and unloading chamber 140 after taking it out of the first separation chamber 120A; Step S303, closing the plug valve 150 between the transfer chamber 130 and the first separation chamber 120A, and closing the plug valve 150 between the transfer chamber 130 and the loading and unloading chamber 140; Step S304: Open the second stop valve 2322 of the upper and lower material cabins 140, and use the vacuum pump 231 to pump the protective gas in the upper and lower material cabins 140 to the gas recovery terminal 234. If necessary, increase or decrease the gas extraction capacity of the vacuum pump 231 from the upper and lower material cabins 140 through the corresponding regulating valve 2321, and open the corresponding third stop valve 213 to confirm that the gas pressure gradually reaches the second vacuum level. Step S305: close the second stop valve 2322 of the upper and lower material cabins 140, open the gate valve 150 between the upper and lower material cabins 140 and the environment outside the furnace, and allow the external environment gas of the silicon carbide epitaxial furnace to flow into the upper and lower material cabins 140 and reach the external environment pressure of the silicon carbide epitaxial furnace; Step S306: Close the gate valve 150 between the upper and lower material chambers 140 and the environment outside the furnace, open the gate valve 150 between the upper and lower material chambers 140 and the carrier 3, use the second robot 2 to grab the epitaxial wafer from the upper and lower material chambers 140, and place it into the carrier 3; Step S307, closing the gate valve 150 between the upper and lower material cabins 140 and the carrier 3; and Step S308: This procedure ends, and the carrier 3 carries the epitaxial wafer to proceed to the next process.

[0083] It should be noted that before the epitaxial wafer loaded on the carrier 160 is placed on any separation cabin 120 and the epitaxial wafer is unloaded from the corresponding carrier 160, the gate valve 150 and all the shut-off devices 22 of the separation cabin 120 are closed to form a seal for the separation cabin 120; while maintaining the sealing of the separation cabin 120, the operations of filling any reaction cabin 110 with protective gas until the reaction gas in the reaction cabin 110 is evacuated and filling the cabin with reaction gas are performed successively.

[0084] In some embodiments, as Figure 9 As shown, the pressure control of the furnace chamber 10 includes the following steps: Step R1, after the controller 214 triggers the cavity pressure control signal, it is determined whether the furnace chamber 10 has completed vacuuming. If not, step R2 is executed; if so, step R3 is executed; Step R2, vacuuming the furnace chamber 10; Step R3, after the furnace chamber 10 is evacuated, the shutoff device 22 and the second shutoff valve 2322 are opened, and the pressure is controlled by the regulating valve 2321; Step R4, determining whether the furnace chamber 10 reaches the pressure setting value, if not, executing step R5; if yes, executing step R6; Step R5, regulating valve 2321 continues to control pressure; Step R6, end pressure control.

[0085] In some embodiments, as Figure 10 As shown, the backfilling of the furnace chamber 10 includes the following steps: Step Q1, after the controller 214 triggers the cavity backfill signal, it is judged whether the furnace chamber 10 is currently completed vacuumizing, if not, step Q2 is executed; if yes, step Q3 is executed; Step Q2, the furnace chamber 10 is vacuumized; Step Q3, the cutoff device 22 is opened, and the second cutoff valve 2322 and the regulating valve 2321 are closed; Step Q4, it is judged whether the furnace chamber 10 reaches the atmospheric setting value, if not, step Q5 is executed; if yes, step Q6 is executed; Step Q5, the furnace chamber 10 is continuously filled with gas; Step Q6, the backfilling of gas is ended.

[0086] In summary, the embodiment of the present application designs the silicon carbide epitaxial furnace 1 with multiple material channels, and provides it with a gas environment management system 20, realizes independent gas environment control of each furnace chamber 10, minimizes the influence of the transmission process of the substrate and the epitaxial wafer as the material between the furnace chambers 10 and between the inside and outside of the furnace on the epitaxial process, and improves the production efficiency of the silicon carbide epitaxial furnace 1.

[0087] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A gas environment management system (20) suitable for a silicon carbide epitaxial furnace (1), It is characterized by: The gas environment management system (20) is independently connected to the reaction chamber (110) of the silicon carbide epitaxial furnace (1), the gas environment management system (20) is independently connected to the transfer chamber (130) of the silicon carbide epitaxial furnace (1), and the gas environment management system (20) is independently connected to the upper and lower material chambers (140) of the silicon carbide epitaxial furnace (1). The gas environment management system (20) independently controls the gas environments of the reaction chamber (110), the transfer chamber (130), and the upper and lower material chambers (140). When a chemical vapor deposition process is carried out in any reaction chamber (110) and its reaction gas environment is maintained, the gas environment management system (20) can change the gas environment of the transfer chamber (130) and the upper and lower material chambers (140). The gas environment management system (20) enables the transfer cabin (130) and the upper and lower material cabins (140) to have two non-reactive gas environments, wherein the two non-reactive gas environments are a protective gas environment and an external gas environment of the silicon carbide epitaxial furnace (1).

2. The gas environment management system (20) according to claim 1, characterized in that: The gas environment management system (20) comprises a functional gas release subsystem (220) and a gas ion extraction system (230), wherein the functional gas release subsystem (220) comprises at least a reaction gas source and a protective gas source, wherein the reaction gas source is connected to the reaction chamber (110) via a pipeline, and the protective gas source is connected to the reaction chamber (110), the transfer chamber (130), and the upper and lower material chambers (140) via a pipeline; Independently controlled shutoff devices (22) are provided on the pipeline between the reaction gas source and the reaction chamber (110), the pipeline between the reaction gas source and the transfer chamber (130), the pipeline between the reaction gas source and the upper and lower material chambers (140), the pipeline between the protective gas source and the reaction chamber (110), the pipeline between the protective gas source and the transfer chamber (130), and the pipeline between the protective gas source and the upper and lower material chambers (140); The gas ion extraction system (230) has a vacuum pump (231), which is connected to the reaction chamber (110), the transfer chamber (130), and the upper and lower material chambers (140) through pipelines. Independently controlled regulating devices (232) are provided on the pipelines between the vacuum pump (231) and the reaction chamber (110), the pipelines between the vacuum pump (231) and the transfer chamber (130), and the pipelines between the vacuum pump (231) and the upper and lower material chambers (140).

3. The gas environment management system (20) according to claim 2, characterized in that: The cut-off device (22) of the functional gas release subsystem (220) and the regulating device (232) of the gas ion extraction system (230) can be opened simultaneously to maintain a reactive gas environment or a protective gas environment.

4. The gas environment management system (20) according to claim 3, characterized in that: The gas environment management system (20) further comprises a plurality of barometer groups, wherein the plurality of barometer groups are respectively connected to the reaction chamber (110), the transfer chamber (130) and the upper and lower material chambers (140) through pipelines, the barometer groups comprising a first barometer (211) and a second barometer (212) having a pressure measuring range smaller than that of the first barometer (211), the second barometer (212) being equipped with a cut-off device (213), and when the air pressure of the reaction chamber (110), the transfer chamber (130) and the upper and lower material chambers (140) is within the pressure measuring range of the second barometer (212), the cut-off device (213) is opened.

5. The gas environment management system (20) according to claim 4, characterized in that: A gate valve (150) is provided between the transfer cabin (130) and the reaction cabin (110) and the upper and lower material cabins (140), and a gate valve (150) is provided between the upper and lower material cabins (140) and the environment outside the furnace. When the gate valve (150) is opened, the gas environment on both sides of the gate valve (150) is made to converge.

6. The gas environment management system (20) according to claim 5, characterized in that: The connection mode of the gas environment management system (20) and the separation cabin (120) of the silicon carbide epitaxial furnace (1) is the same as the connection mode of the gas environment management system (20) and the reaction cabin (110); the connection mode of the transfer cabin (130) and the separation cabin (120) is the same as the connection mode of the transfer cabin (130) and the reaction cabin (110).

7. The gas environment management system (20) according to claim 5, characterized in that: Each regulating device (232) includes a regulating valve (2321) and a stop valve (2322); the regulating valves (2321) of the plurality of regulating devices (232) are connected to the vacuum pump (231); and the stop valves (2322) of the plurality of regulating devices (232) are independently connected to the reaction chamber (110), the transfer chamber (130), and the upper and lower material chambers (140).

8. A gas environment management method, applied to the gas environment management system (20) according to any one of claims 1 to 7, characterized in that: The steps include: When a chemical vapor deposition process is performed in a reaction chamber (110) of a silicon carbide epitaxial furnace (1), a reaction gas environment in the reaction chamber (110) is maintained by the gas environment management system (20); The upper and lower material chambers (140) are connected to the environment outside the furnace, the upper and lower material chambers (140) are in the external gas environment of the silicon carbide epitaxial furnace (1), and the substrates are placed in the upper and lower material chambers (140); Separating the upper and lower material cabins (140) from the environment outside the furnace and evacuating the upper and lower material cabins (140); Filling the upper and lower material cabins (140) with protective gas until the upper and lower material cabins (140) are in a protective gas environment; Maintaining the protective gas environment of the transfer cabin (130), connecting the upper and lower cabins (140) with the transfer cabin (130), and transferring the substrate into the transfer cabin (130); After the previous chemical vapor deposition process is completed in the reaction chamber (110), the substrate is placed in the reaction chamber (110) to perform the next chemical vapor deposition process.

9. The gas environment management method according to claim 8, characterized in that: The gas environment management system (20) includes a vacuum pump (231) and a plurality of regulating devices (232), each of the regulating devices (232) includes a regulating valve (2321) and a stop valve (2322), the regulating valves (2321) of the plurality of regulating devices (232) are all connected to the vacuum pump (231), and the stop valves (2322) of the plurality of regulating devices (232) are independently connected to the reaction chamber (110), the transfer chamber (130), and the upper and lower material chambers (140); The process of vacuuming the upper and lower material compartments (140) is as follows: The upper and lower material cabins (140) are controlled to be in a closed state, and the stop valve (2322) is opened, and the regulating valve (2321) is opened by 1% per second until the upper and lower material cabins (140) reach a first vacuum degree; The transfer cabin (130) is controlled to be in a closed state, and the regulating valve (2321) is opened by 5% per second until the regulating valve (2321) is fully opened. When the upper and lower cabins (140) reach a second vacuum degree, the upper and lower cabins (140) are evacuated, and the second vacuum degree is greater than the first vacuum degree.

10. A silicon carbide epitaxial furnace (1), comprising: A reaction chamber (110), wherein the reaction chamber (110) is capable of independently performing a chemical vapor deposition process; Upper and lower material cabins (140), the upper and lower material cabins (140) being capable of docking with a carrier (3) outside the furnace to receive substrates from the carrier (3) or to transfer epitaxial wafers to the carrier (3); as well as A transfer cabin (130), wherein the transfer cabin (130) is capable of connecting the reaction cabin (110) and the upper and lower material cabins (140); It is characterized by: The silicon carbide epitaxial furnace (1) further comprises a gas environment management system (20) according to any one of claims 1 to 7, wherein the gas environment management system (20) is capable of executing the gas environment management method according to claim 8 or 9.

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