Vacuum pumping system and method

Abstract

The invention discloses a vacuum pumping system and method. The vacuum pumping system comprises a cavity, at least one low-vacuum pumping pump set, at least one high-vacuum pumping pump set, a first pipeline and a second pipeline, and the low-vacuum pumping pump set communicates with the cavity through the first pipeline and the second pipeline; the low-vacuum air extracting pump set is communicated with the cavity through a first pipeline, the high-vacuum air extracting pump set is communicated with the cavity through a second pipeline, the controller is electrically connected to the low-vacuum air extracting pump set and the high-vacuum air extracting pump set, the controller sequentially controls on-off of the low-vacuum air extracting pump set and the high-vacuum air extracting pump set, and the low-vacuum air extracting pump set can extract pressure in the cavity to be lower than 0.1 Torr; the system comprises a low-vacuum air extracting pump set and a high-vacuum air extracting pump set, and the low-vacuum air extracting pump set and the high-vacuum air extracting pump set can be used for extracting the pressure in the cavity to be lower than 0.1 Torr and the pressure in the cavity to be in an ultrahigh vacuum state respectively. The grading air exhaust mode can more effectively improve the air exhaust efficiency and reduce the air exhaust time; and the equipment can be prevented from being in a high-load state for a long time, so that the service life of the equipment is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of ultra-high vacuum equipment, and particularly to a vacuum pumping system and method. Background Art

[0002] Molecular beam epitaxy technology is a material epitaxial growth technology with very high requirements for vacuum. By heating source materials in an ultra-high vacuum environment to generate atomic or molecular beams and spraying them on the surface of a clean substrate, epitaxial growth of high-quality crystal thin films can be achieved. Current molecular beam epitaxy equipment generally includes three chambers: a sample introduction chamber, a pretreatment chamber, and a growth chamber. Each time when breaking vacuum for sample introduction and sampling, only the sample and the sample carrier need to be placed in the sample introduction chamber, and after isolating the sample introduction chamber from other chambers, the vacuum can be broken, so as to keep the pretreatment chamber and the growth chamber in a high-vacuum state all the time.

[0003] Existing vacuum-breaking methods require wasting a long time waiting for the molecular pump, and then the vacuum in the sample introduction chamber can be restored to start again, with low working efficiency. As a result, the sample, the sample carrier, and the inner wall of the chamber are in contact with the atmospheric environment for a long time, and impurity gases including water vapor, oxygen, etc. will be adsorbed, affecting the vacuum degree of the equipment and the process effect. Each time the sample in the sample introduction chamber is replaced by breaking vacuum, the molecular pump needs to be turned off and then restarted, which has a great impact on the service life of the molecular pump. In addition, in the initial stage of the rough pumping process of the sample introduction chamber cavity using a dry mechanical pump, the pressure in the sample introduction chamber cavity is relatively high, resulting in a large load and energy consumption of the dry mechanical pump, and also having a certain impact on the service life of the dry mechanical pump.

[0004] Therefore, there is a lack of a pumping system with high efficiency for quickly restoring vacuum in the prior art. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the defect that there is a lack of a pumping system for quickly restoring vacuum in the prior art, and to provide a vacuum pumping system and a pumping method.

[0006] The present invention solves the above technical problem by the following technical solutions:

[0007] A vacuum pumping system, the vacuum pumping system includes a cavity, at least one low-vacuum pumping pump group, at least one high-vacuum pumping pump group, a first pipeline and a second pipeline. The first pipeline and the second pipeline are both connected to the cavity. The inner diameter of the first pipeline is larger than the inner diameter of the second pipeline. The low-vacuum pumping pump group is connected to the cavity through the first pipeline and the second pipeline; the high-vacuum pumping pump group is connected to the cavity through the first pipeline;

[0008] Wherein, the low-vacuum pumping pump group can pump the pressure in the cavity to be lower than 0.1 Torr; the high-vacuum pumping pump group can pump the cavity to ultra-high vacuum.

[0009] In this solution, the system includes a low-vacuum pumping unit and a high-vacuum pumping unit, which can pump the pressure in the cavity to below 0.1 Torr and ultra-high vacuum state respectively. This way of staged pumping can more effectively improve the pumping efficiency and reduce the pumping time; by the controller, the low-vacuum pumping unit is controlled to switch to pumping through the second pipeline and the first pipeline successively, reducing the load of the mechanical pump, and avoiding the equipment being in a high-load state for a long time, thus prolonging the service life of the equipment. Through the controller, the on and off of the low-vacuum pumping unit and the high-vacuum pumping unit can be automatically controlled. This makes the operation more convenient, reduces the frequency of manual intervention, and improves the working efficiency of vacuum pumping.

[0010] Preferably, the low-vacuum pumping unit further includes at least two valves and a mechanical pump. At least two of the valves are arranged on the side wall of the cavity and communicate with the cavity, and at least two of the valves communicate with the mechanical pump through the first pipeline and the second pipeline.

[0011] In this solution, by adding at least two valves, the pressure in the cavity can be controlled more precisely. These valves can be arranged on the side wall of the cavity and communicate with the cavity, enabling the system to control the pressure in the cavity more accurately. This design improves the safety and reliability of the system; longer service life: due to the addition of the mechanical pump, the system can more effectively pump out the gas from the cavity, thus prolonging the service life of other components in the system.

[0012] Preferably, the low-vacuum pumping unit further includes two valves, namely a large-angle valve and a small-angle valve. The large-angle valve and the small-angle valve communicate with the cavity respectively.

[0013] One end of the first pipeline communicates with the large-angle valve, and the other end of the first pipeline communicates with the mechanical pump; one end of the second pipeline communicates with the small-angle valve, and the other end of the second pipeline communicates with the first pipeline.

[0014] In this solution, by combining the use of the first pipeline and the second pipeline of the low-vacuum pumping unit and the high-vacuum pumping unit, the vacuum pumping efficiency can be further improved. This design enables the system to reach the required vacuum degree in a shorter time; by using the first pipeline and the second pipeline, the wear and fatigue of each component in the system can be reduced.

[0015] Preferably, the high-vacuum pumping unit further includes a gate valve, a molecular pump and a mechanical pump; the gate valve communicates with the cavity, the molecular pump is adjacent to the gate valve, and the molecular pump communicates with the mechanical pump through the first pipeline.

[0016] In this solution, by using a molecular pump, the vacuum degree of the cavity can be further improved. The molecular pump can more effectively extract gas molecules from the cavity, enabling the cavity to reach a higher vacuum degree. By connecting the molecular pump to a mechanical pump, the pumping rate can be further increased. The mechanical pump can provide a greater pumping capacity, while the molecular pump can more effectively extract gas molecules from the cavity. This design allows the system to reach the required vacuum degree in a shorter time. By using a gate valve, the impact and wear of gas on each component in the system can be reduced. The gate valve can effectively control the gas flow, thereby reducing the impact and pressure of gas on other components and extending the service life of each component in the system.

[0017] Preferably, the vacuum pumping system further includes a flange, and the flange is provided between the gate valve and the cavity.

[0018] In this solution, the flange can effectively connect the gate valve and the cavity together to form a sealed channel, reducing the possibility of gas leakage, thereby improving the sealing performance and reliability of the system. By setting the flange, the connection between the gate valve and the cavity can be made more stable. During operation, the flange can provide better support and fixation, reducing the shaking and deformation of the gate valve and the cavity, and improving the operation stability of the system.

[0019] Preferably, the vacuum pumping system further includes a vent valve, the vent valve is connected to the cavity, and the vent valve is arranged on the side of the cavity.

[0020] In this solution, the vent valve is arranged on the side of the cavity, making it more convenient for the operator to access and operate the vent valve. Since the vent valve is arranged on the side of the cavity, it is easier to maintain and replace it.

[0021] Preferably, the vacuum pumping system further includes a vacuum gauge, the vacuum gauge is connected to the cavity and is arranged on the side wall of the cavity.

[0022] In this solution, the vacuum gauge can monitor the vacuum degree of the cavity in real time, enabling the operator to timely understand the change of the vacuum degree. This design allows the operator to timely adjust the system parameters to ensure the normal operation of the system.

[0023] Preferably, the vacuum pumping system further includes a cavity door and a second gate valve, and the cavity door and the second gate valve are respectively arranged at both ends of the cavity.

[0024] In this solution, the chamber door effectively seals the chamber, creating a sealed space. This design reduces the possibility of gas leakage, thereby improving the system's sealing and reliability. The second gate valve can be used to control fluid flow by adjusting the position of the gate. When the gate is fully open, fluid can pass through the valve unimpeded. When the gate is closed, the valve completely shuts off fluid flow, facilitating flow control and maintenance.

[0025] A method for pumping air using the vacuum pumping system as described above, the method comprising:

[0026] S1: rupture the cavity;

[0027] S2: Use a low vacuum pump group to perform a first-stage rough pumping, that is, open the small angle valve, and perform a first-stage rough pumping of the cavity through the small angle valve and the second pipeline;

[0028] If the vacuum in the chamber is lower than 10 Torr, proceed to the next step; otherwise, repeat the first-level rough pumping;

[0029] S3: Use the low vacuum pump group to perform secondary rough pumping, close the small angle valve, open the large angle valve, and perform secondary rough pumping of the cavity through the large angle valve and the first pipeline;

[0030] If the vacuum in the chamber is lower than 0.1 Torr, proceed to the next step; otherwise, repeat the second-stage rough pumping;

[0031] S4: The cavity is evacuated to ultra-high vacuum using a high vacuum pump set, and the vacuuming of the cavity is completed.

[0032] In this solution, a set of low vacuum pump groups is used to perform two-stage rough pumping on the injection chamber cavity, which avoids the time of waiting for the molecular pump to be closed and opened, shortens the time of single breaking of air to restore vacuum, and improves work efficiency; a set of low vacuum pump groups is used to perform two-stage rough pumping on the injection chamber cavity, which avoids frequent opening and closing of the molecular pump, can increase the service life of the molecular pump, and reduce costs; first, the injection chamber cavity is roughly pumped at one level through the small angle valve and the second pipeline, and then the injection chamber cavity is roughly pumped at two levels through the large angle valve and the first pipeline, which can reduce the energy consumption of the vacuum pumping process, and at the same time can extend the service life of the dry mechanical pump and reduce costs.

[0033] Preferably, in S1, before the step of breaking the cavity, the step further includes:

[0034] Close the plug valve between the molecular pump and the cavity, and open the air-breaking valve for ventilation.

[0035] In this solution, closing the gate valve prevents the cavity from being further evacuated by the molecular pump, and opening the air-breaking valve can quickly ventilate the cavity to break the vacuum in the cavity.

[0036] On the basis of conforming to the common knowledge in the art, the above preferred technical solutions can be freely combined to obtain the preferred embodiments of the present application.

[0037] The positive and progressive effects of the present invention are as follows: The system includes a low-vacuum pumping group and a high-vacuum pumping group, which can pump the pressure in the cavity to below 0.1 Torr and ultra-high vacuum state respectively. This hierarchical pumping method can more effectively improve the pumping efficiency and reduce the pumping time; by controlling the low-vacuum pumping group to pump air through the second pipeline and the first pipeline successively by the controller, it can avoid the equipment being in a high-load state for a long time, thereby extending the service life of the equipment. Through the controller, the on and off of the low-vacuum pumping group and the high-vacuum pumping group can be automatically controlled. This makes the operation more convenient, reduces the frequency of manual intervention, and improves the working efficiency of vacuum pumping. Brief Description of the Drawings

[0038] Figure 1 It is a schematic structural diagram of a vacuum pumping system according to an embodiment of the present invention.

[0039] Figure 2 It is a flowchart of a pumping method of a vacuum pumping system according to an embodiment of the present invention.

[0040] Description of the Reference Numerals in the Drawings

[0041] Cavity 1

[0042] Second gate valve 2

[0043] Flange 3

[0044] Gate valve 4

[0045] Molecular pump 5

[0046] First pipeline 6

[0047] Mechanical pump 7

[0048] Break vacuum valve 8

[0049] Vacuum gauge 9

[0050] Cavity door 10

[0051] Large angle valve 11

[0052] Second pipeline 12

[0053] Small angle valve 13 Detailed Embodiments

[0054] The present invention will be further described below by way of examples, but the present invention is not limited to the scope of the examples.

[0055] This embodiment provides a vacuum pumping system. The vacuum pumping system includes a cavity 1, at least one low-vacuum pumping group, at least one high-vacuum pumping group, a first pipeline 6, and a second pipeline 12. The low-vacuum pumping group is connected to the cavity 1 through the first pipeline 6 and the second pipeline 12; the high-vacuum pumping group is connected to the cavity 1 through the first pipeline 6, and the on / off of the low-vacuum pumping group and the high-vacuum pumping group is controlled successively; the inner diameter of the first pipeline 6 is larger than the inner diameter of the second pipeline 12.

[0056] Among them, the low-vacuum pumping group can pump the pressure in the cavity 1 to below 0.1 Torr; the high-vacuum pumping group can pump the cavity 1 to an ultra-high vacuum. The switching between the high-vacuum pumping group and the low-vacuum pumping group is realized by the opening and closing of the gate valve 4, the large-angle valve 11, and the small-angle valve 13.

[0057] Among them, the system includes a low-vacuum pumping group and a high-vacuum pumping group, which can pump the pressure in the cavity 1 to below 0.1 Torr and the ultra-high vacuum state respectively. This way of staged pumping can more effectively improve the pumping efficiency and reduce the pumping time; by the controller, successively controlling the low-vacuum pumping group to pump air through the second pipeline 12 and the first pipeline 6, it can avoid the equipment being in a high-load state for a long time, thereby extending the service life of the equipment. This makes the operation more convenient, reduces the frequency of manual intervention, and improves the working efficiency of vacuum pumping.

[0058] In a preferred embodiment, the low-vacuum pumping group further includes at least two valves and a mechanical pump 7. The at least two valves are arranged on the side wall of the cavity 1 and are connected to the cavity 1. The at least two valves are connected to the mechanical pump 7 through the first pipeline 6 and the second pipeline 12. By adding at least two valves, the pressure in the cavity 1 can be controlled more precisely. These valves can be arranged on the side wall of the cavity 1 and are connected to the cavity 1, enabling the system to adjust the pressure in the cavity 1 more accurately. This design improves the safety and reliability of the system; longer service life: due to the addition of the mechanical pump 7, the system can more effectively pump out the gas from the cavity 1, thereby extending the service life of other components in the system.

[0059] In this embodiment, the low-vacuum pumping group further includes two valves, namely the large-angle valve 11 and the small-angle valve 13. The large-angle valve 11 and the small-angle valve 13 are respectively connected to the cavity 1. One end of the first pipeline 6 is connected to the large-angle valve 11, and one end of the first pipeline 6 is connected to the mechanical pump 7; one end of the second pipeline 12 is connected to the small-angle valve 13, and the other end of the second pipeline 12 is connected to the first pipeline 6.

[0060] Specifically, the diameter of the first pipeline 6 is larger than that of the second pipeline 12, which can pump out gas from the cavity 1 more quickly; the diameter of the second pipeline 12 is smaller than that of the first pipeline 6. By first pumping air through the second pipeline 12 and then switching to the first pipeline 6 for pumping, the load on the mechanical pump in the initial stage of pumping can be reduced, the energy consumption can be decreased, and the service life of the components in the system can also be extended.

[0061] Among them, the high-vacuum pumping unit further includes a gate valve 4, a molecular pump 5 and a mechanical pump 7; the gate valve 4 is connected to the cavity 1, the molecular pump 5 is adjacent to the gate valve 4, and the molecular pump 5 is connected to the mechanical pump 7 through the first pipeline 6. By using the molecular pump 5, the vacuum degree of the cavity 1 can be further improved. The molecular pump 5 can more effectively pump out gas molecules from the cavity 1, so that the cavity 1 reaches a higher vacuum degree, that is, ultra-high vacuum; by connecting the molecular pump 5 to the mechanical pump 7, the pumping rate can be further increased; the mechanical pump 7 can provide a greater pumping capacity, while the molecular pump 5 can more effectively pump out gas molecules from the cavity 1. This design enables the system to reach the required vacuum degree in a shorter time. The gate valve 4 can effectively control the gas flow, enabling the cavity 1 to switch between rough pumping and fine pumping, thereby reducing the impact and pressure of the gas on other components and extending the service life of each component in the system.

[0062] Specifically, the vacuum pumping system further includes a flange 3, which is provided between the gate valve 4 and the cavity 1. The flange 3 can effectively connect the gate valve 4 and the cavity 1 together to form a sealed channel, reducing the possibility of gas leakage, thereby improving the sealing performance and reliability of the system. By setting the flange 3, the connection between the gate valve 4 and the cavity 1 can be made more stable. During operation, the flange 3 can provide better support and fixation, thereby reducing the shaking and deformation of the gate valve 4 and the cavity 1 and improving the operation stability of the system.

[0063] Among them, the vacuum pumping system further includes a vent valve 8, which is connected to the cavity 1. The vent valve 8 is arranged on the side of the cavity 1. The vent valve 8 is arranged on the side of the cavity 1, making it more convenient for the operator to access and operate the vent valve 8. Since the vent valve 8 is arranged on the side of the cavity 1, it is easier to maintain and replace it.

[0064] Among them, the vacuum pumping system further includes a vacuum gauge 9, which is connected to the cavity 1 and arranged on the side wall of the cavity 1. The vacuum gauge 9 can monitor the vacuum degree of the cavity 1 in real time, enabling the operator to timely understand the change of the vacuum degree. This design enables the operator to timely adjust the system parameters to ensure the normal operation of the system.

[0065] The vacuum pumping system also includes a chamber door 10 and a second gate valve 2, which are arranged at one end of the chamber 1. The chamber door 10 and the second gate valve 2 can effectively seal the chamber 1, forming a sealed space. This design can reduce the possibility of gas leakage, thereby improving the sealing and reliability of the system. By providing the chamber door 10, the operator can open or close the chamber door 10 as needed, thereby conveniently performing operations such as cleaning, repairing, or replacing the chamber 1. The second gate valve 2 can control the flow of the fluid by adjusting the position of the gate. When the gate is fully open, the fluid can pass through the valve unimpeded. When the gate is closed, the valve can completely cut off the flow of the fluid, facilitating flow control or maintenance and overhaul of the fluid.

[0066] A method for pumping air using the vacuum pumping system as described above, the method comprising:

[0067] S1: Close the gate valve 4 between the molecular pump 5 and the cavity 1, open the air-breaking valve 8 for ventilation, and ventilate the cavity 1;

[0068] S2: Use a low vacuum pump group to perform a first-stage rough pumping, that is, open the small angle valve 13, and perform a first-stage rough pumping of the cavity 1 through the small angle valve 13 and the second pipe 12;

[0069] If the vacuum in chamber 1 is lower than 10 Torr, proceed to the next step; otherwise, repeat the first-level rough pumping.

[0070] S3: Use a low vacuum pump group to perform secondary rough pumping, close the small angle valve 13, open the large angle valve 11, and perform secondary rough pumping on the cavity 1 through the large angle valve 11 and the first pipe 6;

[0071] If the vacuum in chamber 1 is lower than 0.1 Torr, proceed to the next step; otherwise, repeat the second-stage rough pumping.

[0072] S4: The cavity 1 is evacuated to ultra-high vacuum using a high vacuum pump assembly, and the evacuation of the cavity 1 is completed.

[0073] Among them, the two-stage rough pumping of the sampling chamber cavity 1 is performed by a set of low vacuum pump groups, which avoids the time of waiting for the molecular pump 5 to be closed and opened, shortens the time of single breaking of air to restore vacuum, and improves work efficiency; the two-stage rough pumping of the sampling chamber cavity 1 is performed by a set of low vacuum pump groups, which avoids the frequent opening and closing of the molecular pump 5, can increase the service life of the molecular pump 5, and reduce costs; the first-stage rough pumping of the sampling chamber cavity 1 is performed by the small angle valve 13 and the second pipeline 12, and then the second-stage rough pumping of the sampling chamber cavity 1 is performed by the large angle valve 11 and the first pipeline 6, which can reduce the energy consumption of the vacuum pumping process, and at the same time can extend the service life of the dry mechanical pump 7 and reduce costs.

[0074] Use as Figure 1The shown vacuum pumping system restores the vacuum in the sample introduction chamber cavity 1 after breaking the vacuum to change the sample; the flow chart is as Figure 2 shown, and the specific process is as follows:

[0075] Close the gate valve 4 between the turbo molecular pump 5 and the sample introduction chamber cavity 1, open the vacuum breaking valve 8 to ventilate and break the vacuum of the sample introduction chamber cavity 1, and then change the sample. The ventilation and vacuum breaking takes 5 minutes, and changing the sample takes 2 minutes, that is, a total of 7 minutes is required.

[0076] As Figure 2 shown, after the sample change is completed, close the vacuum breaking valve 8, open the small angle valve 13, and use the rough vacuum pumping unit to perform the first-stage rough pumping on the sample introduction chamber cavity 1 through the small angle valve 13 and the second pipeline 12. After the vacuum gauge 9 monitors that the vacuum in the sample introduction chamber cavity 1 is lower than 10 Torr; open the large angle valve 11, close the small angle valve 13, and use the rough vacuum pumping unit to perform the second-stage rough pumping on the sample introduction chamber cavity 1 through the large angle valve 11 and the first pipeline 6. After the vacuum gauge 9 monitors that the vacuum in the sample introduction chamber is lower than 0.1 Torr, close the large angle valve 11, and then open the gate valve 4 between the turbo molecular pump 5 and the sample introduction chamber cavity 1, and switch to the high vacuum pumping unit to perform fine pumping on the sample introduction chamber cavity 1 to restore the vacuum in the sample introduction chamber cavity 1. The two-stage rough pumping process of the dry mechanical pump 7 takes 23 minutes.

[0077] Among them, pumping with the second pipeline 12 is to control the pumping speed, reduce the load of the mechanical pump 7, make the system energy-saving and increase the service life; the turbo molecular pump 5 of the high vacuum pumping unit does not need to be closed and restarted, saving a large amount of pumping time. The entire process of breaking the vacuum in the sample introduction chamber and restoring the vacuum takes 30 minutes in total, and the samples, sample carriers and the inner wall of the chamber in the sample introduction chamber are in contact with the atmospheric environment for 2 minutes. Keep the cavity 1 in better vacuum and achieve better material growth effect.

[0078] The vacuum pumping process in the prior art is as follows:

[0079] First, close the gate valve 4 between the turbo molecular pump 5 and the sample introduction chamber cavity, then turn off the turbo molecular pump 5, and wait for the rotational speed of the turbo molecular pump 5 to drop to 0 rpm. It takes 40 minutes for the rotational speed of the turbo molecular pump 5 to drop to 0 rpm. After the rotational speed of the turbo molecular pump 5 drops to 0 rpm, close the vacuum breaking valve 8, reopen the gate valve 4 between the turbo molecular pump 5 and the sample introduction chamber cavity, and use the dry mechanical pump 7 to perform rough pumping on the sample introduction chamber cavity. After the indication of the vacuum gauge 9 is less than 0.1 Torr, restart the turbo molecular pump 5 to perform fine pumping on the sample introduction chamber cavity to restore the vacuum in the sample introduction chamber cavity. The rough pumping of the dry mechanical pump 7 takes 20 minutes, and the start-up of the turbo molecular pump 5 takes 2 minutes, with a total of 22 minutes required. The entire process of breaking the vacuum in the sample introduction chamber and restoring the vacuum takes 62 minutes in total, and the samples, sample carriers and the inner wall of the chamber in the sample introduction chamber are in contact with the atmospheric environment for 35 minutes.

[0080] Comparing with this embodiment, it can be clearly seen that the time required to restore the vacuum in the sample introduction chamber using the embodiment is reduced from 62 minutes to 30 minutes, improving the working efficiency. For the sample in the sample introduction chamber, the contact time of the sample carrier with the inner wall of the chamber with the atmospheric environment is reduced from 35 minutes to 2 minutes, greatly reducing the adsorption of impurities, maintaining a better vacuum degree in the chamber 1, and thus achieving a better material growth effect. The embodiment does not require the molecular pump 5 to be reopened after being closed to restore the vacuum in the sample introduction chamber, which can extend the service life of the molecular pump 5. And the embodiment avoids the large-load operation in the initial stage of rough pumping of the dry mechanical pump 7, which can save energy and also extend the service life of the dry mechanical pump 7.

[0081] Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that this is only an example. The protection scope of the present invention is defined by the appended claims. Without departing from the principle and essence of the present invention, those skilled in the art can make various changes or modifications to these embodiments, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A vacuum pumping system, characterized in that: The vacuum pumping system comprises: a cavity, a first pipe and a second pipe, wherein the first pipe and the second pipe are both connected to the cavity, and the inner diameter of the first pipe is larger than the inner diameter of the second pipe; and At least one low vacuum pump group and at least one high vacuum pump group, wherein the low vacuum pump group is connected to the cavity through the first pipe and the second pipe respectively; the high vacuum pump group is connected to the cavity through the second pipe; The low vacuum pump group may first pump the pressure in the cavity to below 0.1 Torr; and the high vacuum pump group may then pump the cavity to ultra-high vacuum.

2. The vacuum pumping system according to claim 1, wherein: The low vacuum pump group also includes at least two valves and a mechanical pump. At least two of the valves are arranged on the side wall of the cavity and connected to the cavity. At least two of the valves are connected to the mechanical pump through the first pipe and the second pipe.

3. The vacuum pumping system according to claim 2, wherein: The low vacuum pump group further includes two valves, which are a large angle valve and a small angle valve, respectively. The large angle valve and the small angle valve are connected to the cavity, respectively. One end of the first pipeline is connected to the large-angle valve, and the other end of the first pipeline is connected to the mechanical pump; one end of the second pipeline is connected to the small-angle valve, and the other end of the second pipeline is connected to the first pipeline.

4. The vacuum pumping system according to claim 1, wherein: The high vacuum pump group further includes a gate valve, a molecular pump and a mechanical pump; the gate valve is connected to the cavity, the molecular pump is adjacent to the gate valve, and the molecular pump is connected to the mechanical pump through the first pipeline.

5. The vacuum pumping system according to claim 4, wherein: The vacuum pumping system further includes a flange, which is arranged between the gate valve and the cavity.

6. The vacuum pumping system according to claim 1, wherein: The vacuum pumping system further includes a rupture valve, which is connected to the cavity and is arranged on a side of the cavity.

7. The vacuum pumping system according to claim 1, wherein: The vacuum pumping system further includes a vacuum gauge, which is connected to the cavity and is arranged on a side wall of the cavity.

8. The vacuum pumping system according to claim 1, wherein: The vacuum pumping system further includes a chamber door and a second gate valve, wherein the chamber door and the second gate valve are respectively arranged at two ends of the chamber.

9. A method for pumping air using the vacuum pumping system according to claim 3, characterized in that: The air extraction method comprises: S1: rupture the cavity; S2: Use a low vacuum pump group to perform a first-stage rough pumping, that is, open the small angle valve, and perform a first-stage rough pumping of the cavity through the small angle valve and the second pipeline; If the vacuum in the chamber is lower than 10 Torr, proceed to the next step; otherwise, repeat the first-level rough pumping. S3: Use the low vacuum pump group to perform secondary rough pumping, close the small angle valve, open the large angle valve, and perform secondary rough pumping of the cavity through the large angle valve and the first pipeline; If the vacuum in the chamber is lower than 0.1 Torr, proceed to the next step; otherwise, repeat the second-stage rough pumping; S4: The cavity is evacuated to vacuum using a high vacuum pump set, and the vacuuming of the cavity is completed.

10. The air extraction method according to claim 9, wherein: In S1, before the step of rupturing the cavity, the following steps are further included: Close the plug valve between the molecular pump and the cavity, and open the air-breaking valve for ventilation.

Images