Source material recovery system and method for molecular beam epitaxy equipment

Abstract

The invention discloses a source material recovery system and method for molecular beam epitaxy equipment, the source material recovery system is used for recovering a high vapor pressure source material, the source material recovery system comprises a pre-collection unit and a final recovery unit, the pre-collection unit comprises a first cold shield and a second cold shield, the first cold shield is nested in a growth chamber of the molecular beam epitaxy equipment, and the second cold shield is nested in the growth chamber of the molecular beam epitaxy equipment; the second cold shield is nested in the first cold shield and is used for condensing and adsorbing redundant source materials in the epitaxial growth process; the final recovery unit comprises a recovery chamber and a cold screen grating, the recovery chamber is connected to the growth chamber through a pipeline with a control valve, and the cold screen grating is arranged in the recovery chamber; after the epitaxial growth process is finished, the gas adsorbed by the cold shield in the growth chamber is heated and released, and then the vacuum pump group drives the gas into the recovery chamber, and the gas is condensed, adsorbed and collected by the cold shield grating. The device has the advantages of being compact in structure, convenient to operate, high in reliability and the like, and safe recovery of high-vapor-pressure source materials is achieved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and more specifically to a source material recovery system and method for molecular beam epitaxy equipment. Background Technology

[0002] Modern infrared detector technology semiconductor devices are all based on the HgCdTe (mercury cadmium telluride) material system. The growth of HgCdTe thin films involves the use of large amounts of high-purity mercury. Mercury, a toxic substance with high vapor pressure, gaseous transport properties, and neurotoxicity, is converted into a gaseous state and deposited on the substrate during epitaxy. Excess mercury is deposited within the cavity or collected at the bottom of the cavity, making it impossible to confirm whether it has been effectively collected. Opening the cavity can easily lead to mercury contamination. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a source material recovery system and method for molecular beam epitaxy equipment that is compact, easy to operate, stable and reliable, in order to overcome the shortcomings of the prior art.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A source material recovery system for a molecular beam epitaxy (MBE) apparatus is disclosed. The system recovers high vapor pressure source materials and includes a pre-collection unit and a final recovery unit. The pre-collection unit comprises a first cold screen and a second cold screen. The first cold screen is nested within the growth chamber of the MBE apparatus, and the second cold screen is nested within the first cold screen, positioned above the source furnace. The first and second cold screens are used to condense and adsorb excess source material during the epitaxial growth process. The final recovery unit comprises a recovery chamber and a cold screen grid. The recovery chamber is connected to the growth chamber via a pipe with a control valve, and the cold screen grid is disposed within the recovery chamber. A heating element is provided on the outer wall of the growth chamber. After the epitaxial growth process is completed, the heating element heats the growth chamber, causing the source material adsorbed by the first and second cold screens within the growth chamber to become gaseous and enter the recovery chamber, where it is condensed, adsorbed, and collected by the cold screen grid.

[0005] As a further improvement of the present invention, a vacuum pump group is provided at the top of the recovery chamber to achieve vacuuming inside the growth chamber and the recovery chamber.

[0006] As a further improvement of the present invention, the bottom of the recovery chamber is connected to the recovery tank via a pipe with a first angle valve and a second angle valve. The recovery tank is used to collect the recycled source material. The first angle valve is used to disconnect the recovery chamber from the recovery tank. The second angle valve is connected to a vacuum system for evacuating the recovery tank.

[0007] As a further improvement of the present invention, the first cold screen is a hollow cylindrical structure with through holes on the side to facilitate the installation of the source furnace and to enable communication between the growth chamber and the recovery chamber; the side wall of the first cold screen forms a cooling channel, and the top of the first cold screen is provided with a cooling medium inlet / outlet A; the second cold screen is a hollow frustum-shaped structure with cooling channels on the side wall, and the top of the second cold screen is provided with a cooling medium inlet / outlet B.

[0008] As a further improvement of the present invention, the first cold screen side is provided with a high liquid level probe and a low liquid level probe, respectively, for monitoring the liquid level of the cooling medium in the first cold screen.

[0009] As a further improvement of the present invention, the outer wall of the growth chamber is provided with a first heating garment, which is connected to an external temperature controller.

[0010] As a further improvement of the present invention, a second heating garment is provided on the outer wall of the recovery chamber, and the second heating garment is connected to an external temperature controller; a thermocouple is provided on the side wall of the cold screen grid.

[0011] As a further improvement of the present invention, a gate valve and a vacuum gauge are provided on the connecting pipe between the growth chamber and the recovery chamber.

[0012] As a further improvement of the present invention, the cold screen grille is a hollow cylindrical structure, and the side wall of the cold screen grille forms a cooling channel. A condenser tube assembly is provided on the upper part of the cold screen grille, and the condenser tube assembly is connected to the cooling channel on the side wall of the cold screen grille. A cooling medium inlet / outlet C is provided on the top of the cold screen grille, and a grille is provided on the side of the cold screen grille, and the grille is close to the air inlet of the recovery chamber.

[0013] As a general technical concept, the present invention also provides a method for recovering raw materials for molecular beam epitaxy equipment, which is implemented based on the above-mentioned raw material recovery system for molecular beam epitaxy equipment, and includes the following steps: Step S1: Before the substrate begins epitaxial growth, the vacuum pump group is turned on, and both the growth chamber and the recovery chamber are kept in an ultra-high vacuum state. Cooling medium is introduced into the first cold screen, the second cold screen and the cold screen grid, and the first cold screen, the second cold screen and the cold screen grid are kept in a continuous state of cooling medium so that excess source material during the substrate epitaxial growth process is condensed and adsorbed. Step S2: When the substrate completes epitaxial growth and the source material needs to be recycled, stop the supply of cooling medium to the first and second cold screens, and keep the cooling medium in the cold screen grid. Step S3: After the cooling medium in the first and second cold screens evaporates, the first heating garment is turned on to bake the growth chamber so that the source material adsorbed on the first and second cold screens is heated and sublimated, and enters the recovery chamber through the suction of the vacuum pump group, where it is condensed, adsorbed and collected by the cold screen grid. Step S4: Determine whether the source material in the growth chamber has been completely drained by the monitoring value of the vacuum gauge. If it has not been completely drained, continue to bake the growth chamber. If it has been completely drained, close the gate valve and vacuum pump group, and stop the cooling medium from being introduced into the cold screen grid. Step S5: Open the second heating garment to heat up the recovery chamber, so that the source material adsorbed on the cold screen grid is heated and turns into liquid. Open the first angle valve to let the liquid raw material flow into the recovery tank. Step S6: After all the source material adsorbed on the cold screen grid has flowed into the recovery tank, close the first angle valve, take out the source material in the recovery tank to complete the recovery, put the recovery tank back into the recovery chamber, and then perform vacuuming through the second angle valve.

[0014] Compared with the prior art, the advantages of the present invention are as follows: The present invention relates to a source material recovery system and method for molecular beam epitaxy (MBE) equipment. A pre-collection unit, consisting of a first and second cold screen disposed within the growth chamber, condenses and adsorbs excess source material during the epitaxial growth process. Simultaneously, the first and second cold screens also condense and adsorb gases released from other materials within the chamber, ensuring an ultra-high vacuum state. The recovery chamber is connected to the growth chamber via a pipe equipped with a vacuum gauge and control valve. A cold screen grid is installed within the recovery chamber, and a heating element is installed on the outer wall of the growth chamber. After the epitaxial growth process is completed, the growth chamber is heated. The source material gas adsorbed by the first and second cold screens within the growth chamber is heated and becomes gaseous. This gas is then drawn into the recovery chamber by a vacuum pump and condensed and collected by the cold screen grid. This significantly improves the recovery quality of high vapor pressure source materials, avoids source material contamination after opening the chamber, and enhances the production safety of the MBE equipment. Attached Figure Description

[0015] Figure 1 This is a schematic diagram illustrating the structural principle of the source material recovery system for molecular beam epitaxy equipment in a specific embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the assembly structure principle of the first cold screen and the second cold screen in a specific embodiment of the present invention; Figure 3 This is a schematic diagram illustrating the structural principle of the second cold screen in a specific embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the structural principle of the cold screen grille in a specific embodiment of the present invention; Figure 5 This is a schematic diagram of the structural principle of the cold screen grille from another perspective in a specific embodiment of the present invention; Figure 6 This is a schematic diagram of the raw material recycling process in a specific embodiment of the present invention.

[0016] Legend: 1. First cold shield; 2. Second cold shield; 3. Cold shield grid; 31. Grid; 32. Condenser tube assembly; 4. Vacuum pump assembly; 5. Recovery tank; 6. First heating garment; 7. Gate valve; 8. High level probe; 9. Low level probe; 10. Second heating garment; 11. Vacuum gauge; 12. First angle valve; 13. Second angle valve; 14. Thermocouple; 100. Growth chamber; 101. Source furnace; 102. Substrate; 200. Recovery chamber; A, B, and C are all inlets and outlets for cooling media. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0018] In the description of this invention, it should be understood that the terms "side", "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more unless otherwise explicitly specified.

[0020] Example like Figure 1As shown, the feed recovery system for molecular beam epitaxy (MBE) equipment of the present invention is mainly used to recover feed materials with high vapor pressure, such as Hg (mercury). The feed recovery system includes a pre-collection unit and a final recovery unit. The pre-collection unit includes a first cold screen 1 and a second cold screen 2. The first cold screen 1 is nested within the growth chamber 100 of the MBE equipment, and the second cold screen 2 is nested within the first cold screen 1, located above the source furnace 101. The substrate 102 is positioned above the source furnace 101 via a sample holder, meaning the second cold screen 2 surrounds the sample holder within the growth chamber 100. The first and second cold screens 1 and 2 are used to condense and adsorb excess feed material during the epitaxial growth process. During the epitaxial growth process, liquid nitrogen is circulated through the first and second cold screens 1 and 2 respectively as a cooling medium. When gaseous feed material comes into contact with the circulating liquid nitrogen cold screens, it forms solid feed material and is adsorbed onto the cold screen walls. Feed material not adsorbed onto the cold screens also becomes liquid feed material and remains at the bottom of the first cold screen 1, completing the pre-collection. Meanwhile, the first cold screen 1 and the second cold screen 2 can also condense and adsorb gases released from other materials within the chamber, ensuring an ultra-high vacuum state within the chamber. The final recovery unit includes a recovery chamber 200 and a cold screen grid 3. The recovery chamber 200 is connected to the growth chamber 100 via a pipe equipped with a gate valve 7 and a vacuum gauge 11. The cold screen grid 3 is located inside the recovery chamber 200. The outer wall of the growth chamber 100 is equipped with a heating element. After the epitaxial growth process is completed, the growth chamber 100 is heated by the heating element, causing the source material adsorbed by the first cold screen 1 and the second cold screen 2 within the growth chamber 100 to be heated and turned into a gaseous state, entering the recovery chamber 200, where it is condensed, adsorbed, and collected by the cold screen grid 3.

[0021] In this embodiment, the surfaces of the first cold screen 1, the second cold screen 2, and the cold screen grid 3 are all sandblasted, which greatly increases the surface area of ​​their condensation source material.

[0022] In this embodiment, a pre-collection unit is formed by the first cold screen 1 and the second cold screen 2 set in the growth chamber 100, which realizes the condensation and adsorption of excess source material during the epitaxial growth process. The recovery chamber 200 is connected to the growth chamber 100 through a pipeline with a vacuum gauge 11 and a control valve. A cold screen grid 3 is set in the recovery chamber 200. After the epitaxial growth process is completed, the source material gas in the growth chamber 100 enters the recovery chamber 200 and can be condensed and adsorbed by the cold screen grid 3. This significantly improves the recovery quality of high vapor pressure source material, avoids source material contamination after opening the chamber, and improves the production safety of the molecular beam epitaxy equipment.

[0023] like Figure 1As shown, a vacuum pump assembly 4 is installed at the top of the recovery chamber 200 to achieve vacuuming inside the growth chamber 100 and the recovery chamber 200, and to drive the gas in the growth chamber 100 into the recovery chamber 200. The bottom of the recovery chamber 200 is connected to the recovery tank 5 through a pipe with a first angle valve 12 and a second angle valve 13. The recovery tank 5 is used to collect the recovered source material. The first angle valve 12 is used to connect and disconnect the recovery chamber 200 from the recovery tank 5, so that the source material in the recovery chamber 200 flows smoothly into the recovery tank 5. The second angle valve 13 is connected to the vacuuming system for vacuuming the recovery tank 5.

[0024] like Figure 2 As shown, the first cold screen 1 is a hollow cylindrical structure with multiple through holes on its side to facilitate the installation of the source furnace 101 or other functional components within the growth chamber 100, and to enable communication between the growth chamber 100 and the recovery chamber 200. Cooling channels are formed on the sidewalls of the first cold screen 1, and a cooling medium inlet / outlet A is provided at the top of the first cold screen 1 to allow the cooling medium to enter and exit the cooling channels of the first cold screen 1. Figure 3 As shown, the second cold screen 2 is a hollow frustum-shaped structure. The sidewalls of the second cold screen 2 form cooling channels, and the top of the second cold screen 2 is provided with a cooling medium inlet / outlet B to realize the cooling medium entering and exiting the cooling channels of the second cold screen 2.

[0025] like Figure 1 As shown, a high liquid level probe 8 and a low liquid level probe 9 are respectively provided on the side of the first cold screen 1 to monitor the liquid level of the cooling medium in the first cold screen 1, thereby ensuring that the cooling medium is continuously present in the first cold screen 1 during the epitaxial growth process, and the first cold screen 1 is always in a low temperature state, which can also save the amount of liquid nitrogen used.

[0026] like Figure 4 and Figure 5 As shown, the cold screen grid 3 is a hollow cylindrical structure with cooling channels formed on its sidewalls. A condenser tube assembly 32 is located at the top of the cold screen grid 3, communicating with the cooling channels on its sidewalls. A cooling medium inlet / outlet C is located at the top of the cold screen grid 3 to allow the cooling medium to enter and exit the cooling channels. A grid 31 is also located on the side of the cold screen grid 3, close to the air inlet of the recovery chamber 200. By setting up the grid 31 and the condenser tube assembly 32, the path of the source material can be effectively blocked without affecting gas flow; the source material will be adsorbed upon contact with the cold screen grid 3.

[0027] like Figure 1 As shown, a thermocouple 14 is provided on the side wall of the cold screen grid 3. The temperature data fed back by the thermocouple 14 is used to determine whether there is liquid nitrogen in the cold screen grid 3, so as to ensure that the source material is adsorbed and intercepted.

[0028] In this embodiment, the outer wall of the growth chamber 100 is provided with a first heating garment 6 as a heating component, and the first heating garment 6 is connected to an external temperature controller. Furthermore, the outer wall of the recovery chamber 200 is provided with a second heating garment 10, and the second heating garment 10 is connected to an external temperature controller.

[0029] like Figure 6 As shown, this embodiment also provides a method for recovering mercury source material for molecular beam epitaxy equipment, which is implemented based on the above-mentioned source material recovery system for molecular beam epitaxy equipment, and includes the following steps: Step S1: Before the epitaxial growth of substrate 102 begins, the vacuum pump group 4 is turned on to maintain an ultra-high vacuum state in both the growth chamber 100 and the recovery chamber 200. A vacuum gauge is installed in the growth chamber 100 to monitor the vacuum level changes in real time. Liquid nitrogen is introduced into the first cold screen 1 and the second cold screen 2 as a cooling medium. When the liquid nitrogen in the first cold screen 1 reaches the high liquid level probe 8, the cooling medium inlet valves of the first cold screen 1 and the second cold screen 2 are automatically closed. After the epitaxial growth process has been running for a period of time, the liquid nitrogen level in the first cold screen 1 and the second cold screen 2 drops. When the liquid nitrogen level in the first cold screen 1 is lower than the low liquid level probe 9, the cooling medium inlet valves of the first cold screen 1 and the second cold screen 2 are automatically opened again to introduce liquid nitrogen. Through liquid level monitoring and control, it is ensured that the first cold screen 1 and the second cold screen 2 always have liquid nitrogen during the epitaxial growth process. At the same time, liquid nitrogen is also continuously introduced into the cold screen grid 3 as a cooling medium.

[0030] Liquid nitrogen has a temperature of -196℃. Under standard atmospheric pressure, mercury has a melting point of -38℃ and a boiling point of 356.7℃. In a vacuum, mercury's melting point is -38℃, and its boiling point is significantly lower. During the epitaxial growth process, most of the mercury atoms adhere to the first cold screen 1 and the second cold screen 2.

[0031] Step S2: When the substrate 102 has completed several rounds of epitaxial growth and it is necessary to recover the mercury source material, stop the flow of liquid nitrogen into the first cold screen 1 and the second cold screen 2. Liquid nitrogen will continue to be present in the cold screen grid 3, which is equivalent to the cold screen grid 3 acting as a cold head.

[0032] Step S3: After the liquid nitrogen in the first cold screen 1 and the second cold screen 2 evaporates, turn on the first heating garment 6 to bake the growth chamber 100 at a temperature of 160~200℃, so that the mercury source material adsorbed on the first cold screen 1 and the second cold screen 2 will be heated and sublimated, move towards the vacuum pump group 4, enter the recovery chamber 200, and be condensed, adsorbed and collected by the cold screen grid 3.

[0033] Step S4: Determine whether the mercury source material in the growth chamber 100 has been completely purged using the monitoring value of the vacuum gauge 11. If it has not been completely purged, the vacuum state in the growth chamber 100 will be relatively poor, and the growth chamber 100 will continue to be baked. If it has been completely purged, close the gate valve 7 and the vacuum pump group 4, and stop the supply of cooling medium to the cold screen grid 3.

[0034] Step S5: Open the second heating garment 10 to heat up the recovery chamber 200, so that the mercury source material adsorbed on the cold screen grid 3 is heated and turns into liquid. Open the first angle valve 12 to allow the liquid mercury to flow into the recovery tank 5.

[0035] Step S6: After all the mercury source material adsorbed on the cold screen grid 3 has flowed into the recovery tank 5, close the first angle valve 12 and remove the mercury from the recovery tank 5, thus completing the recovery. Then, put the recovery tank 5 back into the recovery chamber 200, and then evacuate it through the second angle valve 13, ready for the next round of source material recovery. The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A source material recovery system for molecular beam epitaxy equipment, characterized in that, The source material recovery system is used to recover high vapor pressure source materials. The source material recovery system includes a pre-collection unit and a final recovery unit. The pre-collection unit includes a first cold screen (1) and a second cold screen (2). The first cold screen (1) is nested in the growth chamber (100) of the molecular beam epitaxy equipment, and the second cold screen (2) is nested in the first cold screen (1) and located above the source furnace (101). The first cold screen (1) and the second cold screen (2) are used to condense and adsorb excess source materials during the epitaxial growth process. The final recovery unit includes a recovery chamber. (200) and cold screen grid (3), the recovery chamber (200) is connected to the growth chamber (100) through a pipe with a control valve, the cold screen grid (3) is set in the recovery chamber (200); the outer wall of the growth chamber (100) is provided with a heating component. After the epitaxial growth process is completed, the growth chamber (100) is baked by the heating component, so that the source material adsorbed by the first cold screen (1) and the second cold screen (2) in the growth chamber (100) is heated and turned into gaseous state and enters the recovery chamber (200), and is condensed and adsorbed by the cold screen grid (3) and collected.

2. The source material recovery system for molecular beam epitaxy equipment according to claim 1, characterized in that, The top of the recovery chamber (200) is equipped with a vacuum pump group (4) to achieve vacuuming inside the growth chamber (100) and the recovery chamber (200).

3. The source material recovery system for molecular beam epitaxy equipment according to claim 1, characterized in that, The bottom of the recycling chamber (200) is connected to the recycling tank (5) via a pipe with a first angle valve (12) and a second angle valve (13). The recycling tank (5) is used to collect the recycled source material. The first angle valve (12) is used to disconnect the recycling chamber (200) from the recycling tank (5). The second angle valve (13) is connected to a vacuum system for evacuating the recycling tank (5).

4. The feed recovery system for molecular beam epitaxy equipment according to any one of claims 1 to 3, characterized in that, The first cold screen (1) is a hollow cylindrical structure with through holes on the side to facilitate the installation of the source furnace (101) and to connect the growth chamber (100) and the recovery chamber (200); the side wall of the first cold screen (1) forms a cooling channel, and the top of the first cold screen (1) is provided with a cooling medium inlet / outlet A; the second cold screen (2) is a hollow frustum-shaped structure with cooling channels on the side wall, and the top of the second cold screen (2) is provided with a cooling medium inlet / outlet B.

5. The source material recovery system for molecular beam epitaxy equipment according to claim 4, characterized in that, The first cold screen (1) is provided with a high liquid level probe (8) and a low liquid level probe (9) on its side, for monitoring the liquid level of the cooling medium in the first cold screen (1).

6. The source material recovery system for molecular beam epitaxy equipment according to claim 4, characterized in that, The outer wall of the growth chamber (100) is provided with a first heating garment (6), which is connected to an external temperature controller.

7. The feed recovery system for molecular beam epitaxy equipment according to any one of claims 1 to 3, characterized in that, The outer wall of the recovery chamber (200) is provided with a second heating garment (10), which is connected to an external temperature controller; the side wall of the cold screen grid (3) is provided with a thermocouple (14).

8. The feed recovery system for molecular beam epitaxy equipment according to any one of claims 1 to 3, characterized in that, A gate valve (7) and a vacuum gauge (11) are provided on the connecting pipe between the growth chamber (100) and the recovery chamber (200).

9. The feed recovery system for molecular beam epitaxy equipment according to any one of claims 1 to 3, characterized in that, The cold screen grille (3) is a hollow cylindrical structure, and the side wall of the cold screen grille (3) forms a cooling channel. The upper part of the cold screen grille (3) is provided with a condenser tube group (32), which is connected to the cooling channel on the side wall of the cold screen grille (3). The top of the cold screen grille (3) is provided with a cooling medium inlet and outlet C, and the side of the cold screen grille (3) is provided with a grille (31), which is close to the air inlet of the recovery chamber (200).

10. A method for recovering raw materials for molecular beam epitaxy equipment, characterized in that, It is implemented based on the source material recovery system for molecular beam epitaxy equipment as described in any one of claims 1 to 9, and includes the following steps: Step S1: Before the substrate (102) begins epitaxial growth, the vacuum pump group (4) is turned on, and the growth chamber (100) and the recovery chamber (200) are kept in an ultra-high vacuum state. Cooling medium is introduced into the first cold screen (1), the second cold screen (2) and the cold screen grid (3), and the first cold screen (1), the second cold screen (2) and the cold screen grid (3) are kept in a continuous state of cooling medium so that excess source material during the epitaxial growth of the substrate (102) is condensed and adsorbed. Step S2: When the substrate (102) completes epitaxial growth and the source material needs to be recycled, stop the supply of cooling medium to the first cold screen (1) and the second cold screen (2), and the cooling medium will continue to exist in the cold screen grid (3); Step S3: After the cooling medium in the first cold screen (1) and the second cold screen (2) evaporates, turn on the first heating garment (6) to bake the growth chamber (100) so that the source material adsorbed on the first cold screen (1) and the second cold screen (2) is heated and sublimated, and enters the recovery chamber (200) through the suction action of the vacuum pump group (4), and is condensed, adsorbed and collected by the cold screen grid (3); Step S4: Determine whether the source material in the growth chamber (100) has been completely drained by the monitoring value of the vacuum gauge (11). If it has not been drained, continue to bake the growth chamber (100). If it has been drained, close the gate valve (7) and the vacuum pump group (4) and stop the cooling medium from being introduced into the cold screen grid (3). Step S5: Open the second heating garment (10) to heat up the recovery chamber (200) and bake it so that the source material adsorbed on the cold screen grid (3) is heated and becomes liquid. Open the first angle valve (12) so that the liquid raw material flows into the recovery tank (5). Step S6: After all the source material adsorbed on the cold screen grid (3) flows into the recycling tank (5), close the first angle valve (12), take out the source material in the recycling tank (5) to complete the recycling, and then put the recycling tank (5) back into the recycling chamber (200). Then, vacuum is performed through the second angle valve (13).

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