Device and method for controlling internal environment atmosphere of high-vacuum test cavity

Abstract

The invention discloses a device and a method for controlling the internal environment atmosphere of a high-vacuum test cavity, which are used for controlling the internal environment atmosphere of various high-vacuum test cavities. Setting the temperature of the high-vacuum test cavity and the gas mixing cavity to test temperature, wherein the temperature of the gas supply pipeline and each valve is higher than the test temperature; gas required to be prepared is sequentially introduced into the gas mixing cavity according to the partial pressure sequence and the final proportion, and mixed gas is formed; under vacuumizing, mixed gas in the gas mixing cavity is diffused into the high-vacuum test cavity through the needle valve; after inflation is completed, the final pressure intensity of the high-vacuum test cavity is achieved; and closing the valve to start testing. The problem that high-vacuum environment control cannot be achieved through an existing gas distribution method is solved, the environment with the high vacuum of 10 <-5 > Pa to 10 <-2 > Pa can be controllably obtained, particularly, the environment with the high vacuum of 10 <-5 > Pa to 10 <-3 > Pa can be controllably obtained, and the precision is controlled within 1%.

Description

Technical Field

[0001] The present invention discloses a method and a device for controlling the internal environmental atmosphere of a high-vacuum test chamber, which are used to realize the control of the internal environmental atmosphere of various high-vacuum test chambers. Background Art

[0002] With the development of testing technologies, more and more testing devices need to conduct tests under specific environmental atmospheres to simulate the actual usage environments of materials or devices to be tested, so as to obtain more real and effective test results. For example, large testing devices such as scanning electron microscopes, transmission electron microscopes, X-ray photoelectron spectrometers, and extreme ultraviolet spectrometers all require environmental parameters such as air pressure, gas composition, temperature, and humidity under high vacuum. In addition, some typical testing devices that need to control the internal environmental atmosphere of the test chamber also include: gas sensor testing devices, special chip testing devices, altitude environment simulation devices, material thermodynamics performance testing devices, reaction kinetics testing devices, microorganism culture and in-situ testing devices, etc. Most of the devices or environmental atmosphere control methods disclosed in the prior art are for 1 atmosphere, and there are few devices and methods for preparing high vacuum. In particular, high-vacuum atmospheres, especially 10 -5In an environment of Pa to 0.1 Pa, it is very difficult to control the air pressure. No matter how precise the existing air valves (flow meters) are, it is impossible to directly prepare a high-vacuum atmosphere. In particular, for multi-component gases, it is almost impossible to prepare a high-vacuum atmosphere under the existing technology. For example, CN114432944B provides a gas distribution system, which solves the problem in the prior art that when it is necessary to switch standard gases or mixed gases with different concentrations during the instrument test, it is necessary to flush the detection chamber for a long time, which affects the test speed and accuracy; however, this technology is for a 1-atmosphere environment. For example, CN114425247B provides a method for preparing a mixed gas for precisely controlling humidity. Compared with the traditional method of adjusting humidity by flowing gas through a humidifying device, its humidity adjustment is more precise and the controllable range is larger; however, this technology is for a 1-atmosphere environment. For example, CN217248071U provides a gas mixing device, which solves the problem in the prior art that the sensitive devices to be detected in the test chamber are easily damaged during vacuum gas replacement; however, this technology is for a 1-atmosphere environment. For example, CN217273558U provides a gas distribution system with a fast gas replacement function, which solves the problem in the prior art that it takes a long time to switch gases; however, this technology is for a 1-atmosphere environment. It can be seen that the existing gas distribution devices and methods are all aimed at the accuracy of gas concentration, the convenience of gas replacement, the gas distribution efficiency, etc. The formed test environment is 1 atmosphere, and there is no mention of an atmosphere environment below 1 Pa. In particular, even the most precise MFC (gas mass flow controller) currently available, when using the minimum flow rate, the opened gas volume is close to 0.1 Pa, and it is impossible to achieve high vacuum. Therefore, it is necessary to adopt a new technical idea, develop a new atmosphere control device, and adopt a new gas distribution method to obtain a high-vacuum atmosphere environment. Summary of the Invention

[0003] The current gas distribution devices and methods cannot achieve the control of a high-vacuum atmosphere. The present invention discloses a new atmosphere control device and adopts a new gas distribution method to unexpectedly obtain a high-vacuum atmosphere environment. In the present invention, the high vacuum is an environment of 10 -5 Pa to 0.01 Pa. Preferably, the high vacuum is an environment of 10 -5 Pa to 10 -3 Pa; as common knowledge, the high-vacuum air pressure is the total air pressure. The present invention not only solves the problem that the existing gas distribution devices and methods cannot achieve high vacuum, but also can accurately make the atmosphere in the test chamber a high vacuum, solves the callback problem, and can meet the one-time reaction test.

[0004] The present invention adopts the following technical solutions.

[0005] An internal environment atmosphere control device for a high-vacuum test chamber, comprising a gas source, a gas mixing chamber, and a high-vacuum test chamber; the gas mixing chamber is connected to a diaphragm vacuum pump and is connected to a molecular pump through a pneumatic valve; the high-vacuum test chamber is connected to a diaphragm vacuum pump and a molecular pump; the gas mixing chamber is communicated with the high-vacuum test chamber through a gas diffusion tube; the gas diffusion tube is connected to a molecular pump and is provided with a stop valve and a needle valve; the high-vacuum test chamber is communicated with the molecular pump through a gate valve.

[0006] In the present invention, a pneumatic valve is provided between the gas mixing chamber and the diaphragm vacuum pump; the gas mixing chamber can be evacuated by using the pneumatic valve and the diaphragm vacuum pump.

[0007] In the present invention, there are two stop valves on the gas diffusion tube, which are respectively located between the gas mixing chamber and the needle valve, and between the needle valve and the high-vacuum test chamber. Preferably, on the gas diffusion tube, the tube connected to the molecular pump is located between the stop valve close to the high-vacuum test chamber and the needle valve. As common knowledge, the stop valve close to the gas mixing chamber is directly connected to the needle valve.

[0008] In the present invention, one or several of a pneumatic valve, a ball valve, and a needle valve are provided between the gas diffusion tube and the molecular pump. For the first time in the present invention, a molecular pump is connected to the gas diffusion tube, and in combination with the valve, it is creatively proposed to carry out pumping and diffusing gas simultaneously, unexpectedly reducing the amount and increasing the pressure, which is beneficial to the realization of the high-vacuum target air pressure.

[0009] In the present invention, a pneumatic valve is provided between the high-vacuum test chamber and the diaphragm vacuum pump; the high-vacuum test chamber can be evacuated by using the pneumatic valve and the diaphragm vacuum pump to achieve the initial environment.

[0010] In the present invention, the high-vacuum test chamber is provided with a gas inlet; it is used for breaking the vacuum after the test is completed.

[0011] In the present invention, the high-vacuum test chamber and the gas mixing chamber are respectively provided with a pressure sensor; preferably, the high-vacuum test chamber and the gas mixing chamber are respectively provided with 1 to 5 pressure sensors, which is beneficial to accurately displaying the air pressure in the chamber.

[0012] In the present invention, the molecular pump is connected to a diaphragm vacuum pump; further, a pressure sensor is provided on the pipeline between the molecular pump and the diaphragm vacuum pump.

[0013] Further, a pressure sensor is provided on the pipeline between the molecular pump and the high-vacuum test chamber.

[0014] In the present invention, the gas source, the gas mixing chamber, and the high-vacuum test chamber are communicated in sequence, and the gas source and the gas mixing chamber are communicated through a gas delivery pipe; preferably, a gas mass flow controller is provided between the gas source and the gas mixing chamber. As common knowledge, the gas source can be selected as a gas cylinder or other sources that can provide gas, and the number of gas sources is not limited and is selected according to the requirements of the high-vacuum test chamber, generally divided into background gas and target gas.

[0015] In the present invention, the gas source is not directly connected to the high-vacuum test chamber.

[0016] In the present invention, in the high-vacuum test chamber, the air pressure is 10 -5 Pa to 10 -2 Pa, preferably 10 -5 Pa to 10 -3 Pa.

[0017] The present invention discloses a method for controlling the internal environmental atmosphere of a high-vacuum test chamber by using the above-mentioned internal environmental atmosphere control device of the high-vacuum test chamber, including the following steps: (1) Set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature, and the temperatures of the gas supply pipeline and each valve are 5-10°C higher than the test temperature; (2) Pump the high-vacuum test chamber and the gas mixing chamber to a high vacuum; (3) Arrange the gases to be prepared in order of partial pressure magnitude, and sequentially introduce them into the gas mixing chamber according to the final ratio through a gas mass flow controller to form a mixed gas, and the pressure of the mixed gas is 8-12 times the final pressure of the high-vacuum test chamber; (4) Vacuum the gas diffusion tube between the stop valves; then, under vacuum, diffuse the mixed gas in the gas mixing chamber into the high-vacuum test chamber through a needle valve; (5) When the inflation is completed and the final pressure of the high-vacuum test chamber is reached, the control of the internal environmental atmosphere of the high-vacuum test chamber is realized.

[0018] The present invention discloses a method for controlling the internal wet atmosphere of a high-vacuum test chamber by using the above-mentioned internal environmental atmosphere control device of the high-vacuum test chamber, including the following steps: (1) Set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature, the temperatures of the gas supply pipeline and each valve except the steam supply pipeline are 5-10°C higher than the test temperature, and the temperatures of the steam supply pipeline and each valve are 15-20°C higher than the test temperature; (2) Pump the high-vacuum test chamber and the gas mixing chamber to a high vacuum; (3) Arrange the gases to be prepared in order of partial pressure magnitude, and sequentially introduce them into the gas mixing chamber according to the final ratio through a gas mass flow controller to form a mixed gas, and the pressure of the mixed gas is 8-12 times the final pressure of the high-vacuum test chamber; the gases to be prepared include water vapor, and the relative humidity of the final gas is related to the partial pressure of water vapor; (4) Vacuum the gas diffusion tube between the stop valves; then, under vacuum, diffuse the mixed gas in the gas mixing chamber into the high-vacuum test chamber through a needle valve; After inflation is completed, the final pressure of the high-vacuum test chamber is reached, and the control of the wet atmosphere inside the high-vacuum test chamber is achieved.

[0019] A method for high-vacuum testing of a sample using the above-described device for controlling the atmosphere inside a high-vacuum test chamber includes the following steps: (1) Place the sample in the high-vacuum test chamber; then set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature, and the temperatures of the gas supply pipeline and each valve are 5-10 °C higher than the test temperature. (2) Pump the high-vacuum test chamber and the gas mixing chamber to a high vacuum. (3) Sort the gases to be prepared according to the partial pressure, and sequentially introduce them into the gas mixing chamber through the gas mass flow controller according to the final ratio to form a mixed gas, and the pressure of the mixed gas is 8-12 times the final pressure of the high-vacuum test chamber. (4) Evacuate the gas diffusion tube between the stop valves; then, under vacuum, diffuse the mixed gas in the gas mixing chamber into the high-vacuum test chamber through the needle valve. (5) When inflation is completed, the final pressure of the high-vacuum test chamber is reached. (6) Close the valves to start the test.

[0020] A method for high-vacuum wet environment testing of a sample using the above-described device for controlling the atmosphere inside a high-vacuum test chamber includes the following steps: (1) Place the sample in the high-vacuum test chamber; then set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature, and the temperatures of the gas supply pipelines other than the water vapor supply pipeline and each valve are 5-10 °C higher than the test temperature, and the temperatures of the water vapor supply pipeline and each valve are 15-20 °C higher than the test temperature. (2) Pump the high-vacuum test chamber and the gas mixing chamber to a high vacuum. (3) Sort the gases to be prepared according to the partial pressure, and sequentially introduce them into the gas mixing chamber through the gas mass flow controller according to the final ratio to form a mixed gas, and the pressure of the mixed gas is 8-12 times the final pressure of the high-vacuum test chamber; the gases to be prepared include water vapor to provide a wet atmosphere. (4) Evacuate the gas diffusion tube between the stop valves; then, under vacuum, diffuse the mixed gas in the gas mixing chamber into the high-vacuum test chamber through the needle valve. (5) When inflation is completed, the final pressure of the high-vacuum test chamber is reached. (6) Close the valves to start the test.

[0021] Preferably, in the above technical solution, in step (3), a molecular pump is used to correct the pressure in the gas mixing chamber through a needle valve to make it 8-12 times the final pressure of the high-vacuum test chamber; the present invention first proposes that the pressure of the mixed gas is 8-12 times the final pressure of the high-vacuum test chamber, which not only ensures the diffusion ability and efficiency, but also makes the diffusion controllable, which is beneficial to the precise control of high vacuum.

[0022] Preferably, under vacuum, when the mixed gas in the gas mixing chamber diffuses into the high-vacuum test chamber through the needle valve, the needle valve and the molecular pump are used to pump vacuum. Preferably, the conductance of the needle valve is the same as that of the needle valve on the gas diffusion tube.

[0023] In the present invention, the gas supply pipeline includes a gas diffusion tube, a gas delivery tube, etc.; the valves include components such as a gas mass flow controller, a pneumatic valve, a ball valve, a needle valve, etc. As common knowledge, the final pressure of the high-vacuum test chamber is the theoretical (designed) pressure of the chamber environment during high-vacuum testing.

[0024] In the present invention, the gas to be prepared is the atmosphere required for the high-vacuum test chamber during testing. According to the testing requirements, those skilled in the art can select it conventionally. The creativity of the present invention lies in solving the problem that gas cannot be prepared in existing high-vacuum tests; the calculation of the partial pressure and the ratio of each individual gas are conventional techniques; during the gas preparation process, the humidity of the mixed gas is controlled by the partial pressure of water vapor, and the conversion of relative humidity is an existing technique. The order of introducing water vapor should be determined according to its partial pressure ranking among all gas components.

[0025] In the present invention, the heating method is a conventional technique, and it can be in the pipeline, pipe fittings, inside or outside the chamber, or even heating devices such as heating blankets, heating plates, heating rods, heating sleeves, etc. As common knowledge, the heated component can be provided with a temperature sensor or not, and the temperature is controlled according to the heating element.

[0026] The present invention discloses the application of the above-mentioned high-vacuum test chamber internal environment atmosphere control device in controlling the internal environment atmosphere of the high-vacuum test chamber, or in preparing the internal environment atmosphere of the high-vacuum test chamber.

[0027] The present invention discloses the application of the above-mentioned high-vacuum test chamber internal environment atmosphere control device in high-vacuum testing.

[0028] The current gas distribution device and method cannot achieve the control of a high-vacuum atmosphere. It has been found that when the existing gas distribution method is used to control the pressure of a high-vacuum test chamber to 1 Pa, the error reaches 0.1 Pa. This error makes the test unreliable or even impossible to conduct. In particular, the existing gas distribution method can hardly achieve the control of the atmosphere below 0.1 Pa. High-vacuum gas distribution is a necessary condition for in-situ detection of materials, which is called the bottleneck of existing material tests. The present invention discloses a new atmosphere control device and adopts a new gas distribution method to unexpectedly obtain a high-vacuum atmosphere environment and can also introduce a wet atmosphere in high vacuum. According to the device and method of the present invention, a high vacuum of 10 -5 Pa to 0.01 Pa environment can be controllably obtained. In particular, a high vacuum of 10 -5 Pa to 10 -3 Pa environment, and the precision control is within 1%. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic structural diagram of the device for controlling the internal environment atmosphere of the high-vacuum test chamber of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0030] Partial pressure of gas: The partial pressure of a gas (English: partial pressure) refers to the pressure formed by a certain component in a gas mixture when it occupies the same volume of the gas mixture at the same temperature. For example, collect a bottle of air and remove the nitrogen in it, and restore it to the same temperature. The remaining oxygen will still gradually fill the entire gas collection bottle, but the pressure caused by the remaining oxygen alone will be lower than the original one. At this time, the pressure value is the partial pressure value of oxygen in the original air. Assume that all other gases except the i-th gas are excluded from the mixed gas system, while keeping the system volume and temperature unchanged. At this time, the pressure of the gas is called the partial pressure of the i-th gas in the mixed gas, that is, at a given temperature and volume, the pressure when only one i gas exists alone and fills the container.

[0031] At present, the high-vacuum tests of samples are all carried out in an environment without gas distribution. This can investigate the performance of samples under high vacuum, but it is impossible to study the performance of the material to be tested during the reaction with gas. The necessary condition for conducting tests such as scanning electron microscopy, transmission electron microscopy, X-ray energy spectroscopy, and deep ultraviolet spectroscopy in a reaction atmosphere is the preparation of a high-vacuum atmosphere. Existing gas distribution devices and methods are all aimed at the accuracy of gas concentration, convenience of gas replacement, gas distribution efficiency, etc. The formed test environment is 1 atmosphere, and no atmosphere environment below 1 Pa is involved. The present invention adopts a new technical idea, develops a new atmosphere control device, and adopts a new gas distribution method to obtain a high-vacuum atmosphere environment.

[0032] The present invention discloses an internal environmental atmosphere control device for a high-vacuum test chamber, which includes a gas source, a gas mixing chamber, and a high-vacuum test chamber; the gas mixing chamber is connected to a diaphragm vacuum pump and is connected to a molecular pump through a pneumatic valve; the high-vacuum test chamber is connected to a diaphragm vacuum pump and a molecular pump; the gas mixing chamber is communicated with the high-vacuum test chamber through a gas diffusion tube; the gas diffusion tube is connected to a molecular pump and is provided with a stop valve and a needle valve; the high-vacuum test chamber is communicated with the molecular pump through a gate valve; a pneumatic valve is provided between the gas mixing chamber and the diaphragm vacuum pump; by using the pneumatic valve and through the diaphragm vacuum pump, the gas mixing chamber can be evacuated.

[0033] In the present invention, on the gas diffusion tube, there are two stop valves, which are respectively located between the gas mixing chamber and the needle valve, and between the needle valve and the high-vacuum test chamber.

[0034] In the present invention, one or several of a pneumatic valve, a ball valve, and a needle valve are provided between the gas diffusion tube and the molecular pump. For the first time in the present invention, a molecular pump is connected to the gas diffusion tube. Combined with the valve, it creatively proposes to carry out gas extraction and diffusion gas simultaneously, unexpectedly reducing the amount and increasing the pressure, which is beneficial to the realization of the high-vacuum target air pressure.

[0035] In the present invention, a pneumatic valve is provided between the high-vacuum test chamber and the diaphragm vacuum pump; by using the pneumatic valve and through the diaphragm vacuum pump, the high-vacuum test chamber can be evacuated to achieve the initial environment.

[0036] In the present invention, the high-vacuum test chamber is provided with a gas inlet; it is used for breaking the vacuum after the test is completed.

[0037] In the present invention, the high-vacuum test chamber and the gas mixing chamber are respectively provided with a pressure sensor; preferably, the high-vacuum test chamber and the gas mixing chamber are respectively provided with 1 to 5 pressure sensors, which is beneficial to accurately display the air pressure in the chamber.

[0038] Preferably, the gas diffusion tube is provided with a pressure sensor, which can observe whether the air pressure in the tube is high vacuum.

[0039] In the present invention, the molecular pump is connected to a diaphragm vacuum pump; further, a pressure sensor is provided on the pipeline between the molecular pump and the diaphragm vacuum pump.

[0040] Further, a pressure sensor is provided on the pipeline between the molecular pump and the high-vacuum test chamber.

[0041] In the present invention, the gas source, the gas mixing chamber, and the high-vacuum test chamber are connected in sequence, and the gas source and the gas mixing chamber are connected through a gas delivery tube; preferably, a gas mass flow controller is provided between the gas source and the gas mixing chamber. As common knowledge, the gas source can be selected from gas cylinders or other sources that can provide gas. The number of gas sources is not limited and is selected according to the requirements of the high-vacuum test chamber. Generally, it is divided into background gas and target gas.

[0042] The present invention discloses a method for controlling the internal environmental atmosphere of a high-vacuum test chamber by using the above-mentioned internal environmental atmosphere control device for a high-vacuum test chamber, including the following steps: 1. Set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the temperatures required for the test. The temperatures of the gas supply pipeline and each component need to be 5-10°C higher than the test chamber; 2. Pump the high-vacuum test chamber to a high vacuum; 3. Pump the gas mixing chamber to a high vacuum; 4. The total pressure of the gas to be prepared in the high-vacuum test chamber is 10 -5 Pa to 0.01 Pa. Sort the gases to be prepared according to the partial pressure, and sequentially introduce the gases from the gas source through the mass flow controller of the gas according to the final ratio. After the inflation is completed, correct (callback) the pressure in the gas mixing chamber to form a mixed gas 10 times (theoretical) of the total pressure (that is, the total pressure is 10 -4 Pa to 0.1 Pa); 5. Pump the pipeline between the two shut-off valves between the high-vacuum test chamber and the gas mixing chamber to a vacuum; 6. Connect the pipeline between the high-vacuum test chamber and the gas mixing chamber, and introduce the mixed gas inside the gas mixing chamber into the high-vacuum test chamber through the needle valve. During this period, it is necessary to continuously pump the vacuum between the gas mixing chamber and the high-vacuum needle valve to reduce the pressure. Unexpectedly, the technical effect that the pressure in the high-vacuum test chamber is between plus or minus 1% of the target pressure is achieved.

[0043] 7. Close the valve and start the test. As common sense, before step 1 starts, the sample is placed in the high-vacuum test chamber.

[0044] 8. Regarding the control of the wet atmosphere: (1) During the gas preparation process, the wet atmosphere is realized through the partial pressure of water vapor; the conversion of gas concentration, partial pressure, flow rate, etc. is a conventional technology; (2) The water vapor comes from the gas source; (3) The heating temperature of the water vapor pipeline needs to be 10°C higher than the temperature of the gas mixing chamber; (4) The heating temperature of the valve used for water vapor needs to be 10°C higher than the pipeline temperature and 20°C higher than the high-vacuum test chamber; (5) The introduction order of the water vapor should be determined according to its partial pressure ranking among all gas components.

[0045] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. In the present invention, in the high-vacuum test chamber, the air pressure is 10 -5 Pa to 10 -2 Pa, preferably 10-5 Pa to 10 -3 Pa. The components, pipe fittings, and elements used in the present invention are all conventional products. The specific installation, connection, and use are conventional technologies. The present invention creatively combines them synergistically and unexpectedly realizes gas distribution in a high-vacuum environment. Unless otherwise specified, the valves, sensors, and vacuum pumps used in the present invention are all conventional products, which do not affect those skilled in the art's understanding of the technical solution and technical effects of the present invention. For the sake of brevity, some conventional connectors are not shown. The valves, flow meters, and sensors in the drawings can be used according to conventional methods, which do not affect those skilled in the art's understanding of the technical progress of the present invention. Unless otherwise specified, the gas concentrations disclosed in the experiments are volume concentrations. Example 1

[0046] See Figure 1 , a device for controlling the internal environmental atmosphere of a high-vacuum test chamber, including a gas source, a gas mixing chamber, and a high-vacuum test chamber that are connected in sequence; the gas source and the gas mixing chamber are connected through a gas delivery pipe, and the gas mixing chamber is connected to the high-vacuum test chamber through a gas diffusion pipe; The gas mixing chamber is connected to a diaphragm vacuum pump and is connected to a molecular pump through a pneumatic valve V13; a pneumatic valve V12 is provided between the gas mixing chamber and the diaphragm vacuum pump; The high-vacuum test chamber is connected to a diaphragm vacuum pump and a molecular pump; a pneumatic valve V16 is provided between the high-vacuum test chamber and the diaphragm vacuum pump, and the high-vacuum test chamber is connected to the molecular pump through a gate valve; The gas diffusion pipe is connected to a molecular pump and is provided with two stop valves (V11, V15) and a needle valve NV1; the stop valves are respectively located between the gas mixing chamber and the needle valve, and between the needle valve and the high-vacuum test chamber; pneumatic valves V14 and a needle valve NV2 are provided between the gas diffusion pipe and the molecular pump; the stop valve close to the gas mixing chamber is directly connected to the needle valve; The high-vacuum test chamber is provided with a gas inlet; The high-vacuum test chamber and the gas mixing chamber are respectively provided with three pressure sensors, and the gas diffusion pipe is provided with one pressure sensor; A gas mass flow controller (MFC) is provided between the gas source and the gas mixing chamber, and conventional valves (pneumatic valves) are provided before and after it. As common knowledge, the gas source is selected as a gas cylinder, which is divided into background gas and target gas.

[0047] The gas source is not directly connected to the high-vacuum test chamber.

[0048] In the high-vacuum test chamber, the pressure during testing is 10 -5 Pa to 10 -2 Pa.

[0049] The specific structural dimensions of the gas cylinder, gas mixing chamber, high-vacuum test, pipeline, valve, etc. are prior art; pipe fittings such as valves not specifically shown in the figure are conventional products, which can be operated conventionally as needed, or can be not used as needed. For example, the ball valve MV1, pneumatic valve V19, and pneumatic valve V20 are generally not operated.

[0050] Embodiment 2. A method for controlling the internal environmental atmosphere of a high-vacuum test chamber by using the above-mentioned internal environmental atmosphere control device of a high-vacuum test chamber. Among them, the chamber is provided with a heating rod, a pipeline, and a heating sleeve is provided outside the pipe fittings. The target gas is hydrogen, the background gas is nitrogen, the hydrogen concentration is 1%, the designed pressure of the high-vacuum test chamber is 0.001 Pa, and the designed pressure of the gas mixing chamber is 0.01 Pa; the method includes the following steps: (1) Set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature of 50 °C, and the temperatures of the gas supply pipeline and each valve are all 60 °C; (2) Pump the high-vacuum test chamber and the gas mixing chamber to a high vacuum of 10 -6 Pa; (3) Sort according to the partial pressure size, and sequentially introduce nitrogen and hydrogen into the gas mixing chamber through the gas mass flow controller according to the final ratio to form a mixed gas. After the gas distribution is completed, pump air back through the V13-molecular pump, and the pressure of the mixed gas is 1.08×10 -2 Pa to 1.13×10 -2 Pa; (4) Close V11 and V15, open V14, and pump the gas diffusion tube between the stop valves to a high vacuum of 10 -6 Pa through the molecular pump; then keep pumping and open V11 and V15 to diffuse the mixed gas coming out of the gas mixing chamber into the high-vacuum test chamber; the flow conductances of the needle valves NV1 and NV2 are the same. Under the pumping of the V14-molecular pump, the mixed gas can be controllably diffused from V11 to V15 and then enter the high-vacuum test chamber; (5) According to the pressure sensor, when the inflation is completed, the final pressure of the high-vacuum test chamber is reached, and it is stabilized at 0.997×10 -3 Pa to 1.009×10 -3 Pa to achieve the control of the internal environmental atmosphere of the high-vacuum test chamber.

[0051] The entire gas distribution process takes nearly 10 minutes.

[0052] Embodiment 3. A method for high-vacuum testing of a sample by using the above-mentioned internal environmental atmosphere control device of a high-vacuum test chamber, including the following steps: In Embodiment 2, in step (1), first place the sample in the high-vacuum test chamber; then set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature; in step (5), close the valve after the gas distribution is completed and start the test.

[0053] Example 4. A method for controlling the wet atmosphere inside a high-vacuum test chamber using the above-mentioned internal environment atmosphere control device for a high-vacuum test chamber. Among them, the chamber is equipped with a heating rod, pipelines, and heating sleeves are provided outside the pipe fittings. The target gases are hydrogen and water vapor (provided by a water evaporator, which is a conventional technology), the background gas is nitrogen, the hydrogen concentration is 1%, the water vapor concentration is 5%, the designed pressure of the high-vacuum test chamber is 0.0001 Pa, and the designed pressure of the gas mixing chamber is 0.001 Pa. The method includes the following steps: (1) Set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature of 60 °C. The temperatures of the gas supply pipelines except those for transporting water vapor and each valve are all 70 °C, and the temperatures of the gas supply pipelines for transporting water vapor and each valve are all 80 °C; (2) Pump the high-vacuum test chamber and the gas mixing chamber to a high vacuum; (3) Arrange the gases to be prepared in order of partial pressure, and sequentially introduce nitrogen, water vapor, and hydrogen into the gas mixing chamber through a gas mass flow controller according to the final ratio to form a mixed gas. After the gas distribution is completed, use the V13 - molecular pump to pump air back. The pressure of the mixed gas is 0.92×10 -3 Pa to 0.95×10 -3 Pa; (4) Close V11 and V15, open V14, and use the molecular pump to pump the gas diffusion tube between the stop valves to a high vacuum of 10 -6 Pa; then keep pumping and open V11 and V15 to diffuse the mixed gas from the gas mixing chamber into the high-vacuum test chamber; the flow conductances of the needle valves NV1 and NV2 are the same. Under the pumping of the V14 - molecular pump, the mixed gas can be controllably diffused from V11 to V15 and then enter the high-vacuum test chamber; (5) According to the pressure sensor, when the gas filling is completed and the final pressure of the high-vacuum test chamber is reached, it stabilizes at 0.993×10 -4 Pa to 1.01×10 -4 Pa, realizing the control of the wet atmosphere inside the high-vacuum test chamber.

[0054] Example 5. A method for high-vacuum testing of samples using the above-mentioned internal environment atmosphere control device for a high-vacuum test chamber, including the following steps: In Example 4, in step (1), first place the sample in the high-vacuum test chamber; then set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature; in step (5), after the gas distribution is completed, close the valves and start the test.

[0055] After the test is completed, fill the chamber with air to break the vacuum, open the high-vacuum test chamber, and the sample can be taken out or other operations can be performed, which are specific conventional technologies. Control Example

[0056] The inventor previously disclosed a gas distribution system (CN114432944B), a method for preparing a mixed gas for precisely controlling humidity (CN114425247B), a gas mixing device (CN217248071U), and a gas distribution system with a rapid air exchange function (CN217273558U). These technologies are for a 1-atmosphere environment. Based on these methods, no matter how the vacuum pump and valves are selected, when controlling the pressure in the test chamber to 1 Pa, the error reaches 0.1 Pa (the best result). This error makes the test unreliable or even impossible to conduct. In particular, it is almost impossible to achieve an atmosphere control of 0.1 Pa with these gas distribution methods. Comparative Example

[0057] Based on Example 2, the pressure of the mixed gas is regulated to 15 times the designed pressure of the test chamber. After gas distribution in step (4), the air pressure in the test chamber is between 1.09×10 -3 Pa and 1.12×10 -3 Pa, and the error is relatively large.

[0058] Based on Example 2, in step (4), when opening V11 and V15 and diffusing the mixed gas from the gas mixing chamber into the test chamber, closing V14 or not turning on the molecular pump will cause the test chamber to be significantly over-pressurized and unusable.

[0059] High-vacuum gas distribution is a necessary condition for in-situ testing of materials. The prior art cannot achieve high-vacuum gas distribution. The present invention adopts a new technical idea, combining a gas pressure in the gas mixing chamber that is 8 - 12 times higher than that in the test chamber with diffusion under vacuum pumping, unexpectedly achieving high-vacuum gas distribution and providing an atmosphere environment for in-situ high-vacuum testing.

[0060] In this article, the orientation terms such as front, back, up, and down are defined based on the positions of the components in the drawings and the positions of the components relative to each other, just for the clarity and convenience of expressing the technical solution. It should be understood that the use of the orientation terms should not limit the scope of protection claimed in this application.

[0061] Without conflict, the above-mentioned embodiments and the features in the embodiments in this article can be combined with each other.

[0062] The above-disclosed is only a preferred embodiment of the present invention. Of course, it cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention still fall within the scope covered by the present invention.

Claims

1. An internal environmental atmosphere control device for a high-vacuum test cavity, comprising a gas source, a gas mixing chamber, and a high-vacuum test cavity, characterized in that, The gas mixing chamber is connected to a diaphragm vacuum pump and is connected to a molecular pump through a pneumatic valve; the high-vacuum test chamber is connected to a diaphragm vacuum pump and a molecular pump; the gas mixing chamber is communicated with the high-vacuum test chamber through a gas diffusion tube; the gas diffusion tube is connected to a molecular pump and is provided with a stop valve and a needle valve; the high-vacuum test chamber is communicated with the molecular pump through a gate valve.

2. The internal environment atmosphere control device for the high-vacuum test cavity according to claim 1, wherein A pneumatic valve is provided between the gas mixing chamber and the diaphragm vacuum pump; on the gas diffusion tube, there are two stop valves, which are respectively located between the gas mixing chamber and the needle valve, and between the needle valve and the high-vacuum test chamber; one or several of a pneumatic valve, a ball valve, and a needle valve are provided between the gas diffusion tube and the molecular pump; a pneumatic valve is provided between the high-vacuum test chamber and the diaphragm vacuum pump.

3. The internal environment atmosphere control device for the high-vacuum test cavity according to claim 1, characterized in that The high-vacuum test chamber is provided with a gas inlet; the high-vacuum test chamber and the gas mixing chamber are respectively provided with a pressure sensor; the gas source, the gas mixing chamber, and the high-vacuum test chamber are connected in sequence, and the gas source and the gas mixing chamber are connected through a gas delivery pipe.

4. The internal environment atmosphere control device for a high-vacuum test cavity according to claim 1, wherein In the high-vacuum test chamber, the target value of the total pressure of the mixed gas is 10 -5 Pa to 10 -2 Pa.

5. A method for controlling the internal environmental atmosphere of a high-vacuum test chamber by using the internal environmental atmosphere control device of a high-vacuum test chamber according to any one of claims 1 to 4, characterized in that, It includes the following steps: (1) Set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature, and the temperatures of the gas supply pipeline and each valve are 5-10 °C higher than the test temperature; (2) Pump the high-vacuum test chamber and the gas mixing chamber to a high vacuum; (3) Arrange the gases to be prepared in order of partial pressure magnitude, and sequentially introduce them into the gas mixing chamber through a gas mass flow controller according to the final ratio to form a mixed gas, and the pressure of the mixed gas is 8-12 times the final pressure of the high-vacuum test chamber; (4) Vacuum the gas diffusion tube between the stop valves; then, under the vacuum pumping of the molecular pump, diffuse the mixed gas in the gas mixing chamber into the high-vacuum test chamber through the needle valve; (5) When the gas filling is completed and the final pressure of the high-vacuum test chamber is reached, the internal environment atmosphere of the high-vacuum test chamber is controlled.

6. A method for controlling the internal environment wet atmosphere of a high-vacuum test chamber by using the high-vacuum test chamber internal environment atmosphere control device according to any one of claims 1 to 4, including the following steps: (1) Set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature, the temperatures of the gas supply pipelines and each valve except the steam supply pipeline are 5-10 °C higher than the test temperature, and the temperatures of the steam supply pipeline and each valve are 15-20 °C higher than the test temperature; (2) Pump the high-vacuum test chamber and the gas mixing chamber to a high vacuum; (3) Arrange the gases to be prepared in order of partial pressure magnitude, and sequentially introduce them into the gas mixing chamber through a gas mass flow controller according to the final ratio to form a mixed gas, and the pressure of the mixed gas is 8-12 times the final pressure of the high-vacuum test chamber; the gases to be prepared include water vapor; (4) Vacuum the gas diffusion tube between the stop valves; then, under the vacuum pumping of the molecular pump, diffuse the mixed gas in the gas mixing chamber into the high-vacuum test chamber through the needle valve; (5) When the gas filling is completed and the final pressure of the high-vacuum test chamber is reached, the internal environment wet atmosphere of the high-vacuum test chamber is controlled.

7. A method for performing a sample high-vacuum test by using the high-vacuum test chamber internal environment atmosphere control device according to any one of claims 1 to 4, including the following steps: (1) Place the sample into the high-vacuum test chamber; then set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature, and the temperatures of the gas supply pipeline and each valve are 5 - 10 °C higher than the test temperature. (2) Pump the high-vacuum test chamber and the gas mixing chamber to high vacuum. (3) Sort the gases to be prepared according to the partial pressure magnitudes, and sequentially introduce them into the gas mixing chamber through the gas mass flow controllers according to the final ratio to form a mixed gas, and the pressure of the mixed gas is 8 - 12 times the final pressure of the high-vacuum test chamber. (4) Pump the gas diffusion tube between the stop valves to vacuum; then, under the vacuum pumping of the molecular pump, diffuse the mixed gas in the gas mixing chamber into the high-vacuum test chamber through the needle valve. (5) When the gas filling is completed, reach the final pressure of the high-vacuum test chamber. (6) Close the valves and start the test.

8. A method for performing a high-vacuum wet environment test on a sample using the internal environment atmosphere control device of the high-vacuum test chamber according to any one of claims 1 to 4, comprising the following steps: (1) Place the sample into the high-vacuum test chamber; then set the temperatures of the high-vacuum test chamber and the gas mixing chamber to the test temperature, and the temperatures of the gas supply pipeline and each valve except the steam supply pipeline are 5 - 10 °C higher than the test temperature, and the temperatures of the steam supply pipeline and each valve are 15 - 20 °C higher than the test temperature. (2) Pump the high-vacuum test chamber and the gas mixing chamber to high vacuum. (3) Sort the gases to be prepared according to the partial pressure magnitudes, and sequentially introduce them into the gas mixing chamber through the gas mass flow controllers according to the final ratio to form a mixed gas, and the pressure of the mixed gas is 8 - 12 times the final pressure of the high-vacuum test chamber; the gases to be prepared include water vapor. (4) Pump the gas diffusion tube between the stop valves to vacuum; then, under vacuum pumping, diffuse the mixed gas in the gas mixing chamber into the high-vacuum test chamber through the needle valve. (5) When the gas filling is completed, reach the final pressure of the high-vacuum test chamber. (6) Close the valves and start the test.

9. The application of the internal environment atmosphere control device of the high-vacuum test chamber according to any one of claims 1 to 4 in the internal environment atmosphere control of the high-vacuum test chamber, or in the preparation of the internal environment atmosphere of the high-vacuum test chamber.

10. The application of the internal environment atmosphere control device of the high-vacuum test chamber according to any one of claims 1 to 4 in high-vacuum testing.

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