Method for preparing composite air suction film on inner wall of vacuum pipeline and vacuum pipeline

Abstract

The invention relates to the technical field of particle accelerators, in particular to a method for preparing a composite air suction film on the inner wall of a vacuum pipeline and the vacuum pipeline. The preparation method comprises the steps that a vacuum pipeline is pretreated, the vacuum pipeline is installed in a solenoid of a magnetron sputtering coating device, and a TiZr filamentous target and an Ag target are installed in the vacuum pipeline at the same time; depositing a TiZr getter film on the inner wall of the vacuum pipeline by adopting a magnetron sputtering coating process; an Ag functional film is deposited on the side, away from the vacuum pipeline, of the TiZr getter film through the magnetron sputtering coating technology; and carrying out in-situ activation on the TiZr getter film and the Ag functional film. According to the method, the TiZr getter film and the Ag functional film are deposited on the inner wall of the vacuum pipeline, so that a double-layer structure with the Ag functional film as the surface layer and the TiZr getter film as the bottom layer is formed on the inner wall of the vacuum pipeline, and pores of the TiZr getter film can be sealed through the Ag functional film so as to improve the stability of a vacuum chamber.

Description

Technical Field

[0001] This invention relates to the field of particle accelerator technology, and in particular to a method for preparing a composite getter membrane on the inner wall of a vacuum pipe and a vacuum pipe. Background Technology

[0002] In ultra-high vacuum systems, the material properties of the vacuum chamber walls are key factors determining the system's ultimate vacuum level, gas escape rate, and stability. Traditional structural materials such as stainless steel and aluminum alloys continuously release gases such as H2O, H2, CO, and CO2 under high vacuum conditions, limiting the improvement of the ultimate vacuum performance of the vacuum chamber. Furthermore, the dynamic desorption effect induced by beam or radiation irradiation poses a major challenge to large scientific facilities such as accelerators and light sources.

[0003] Non-evaporative getter membrane technology, especially binary or ternary getter membranes such as TiZr and TiZrV, has been widely used in the modification of vacuum chamber walls. These films, after being activated by baking (typically at 180-350℃), can provide distributed pumping capability for active gases at room temperature, significantly reducing static outgassing. However, single getter membranes have the following inherent drawbacks: poor anti-fouling ability; after exposure to the atmosphere or slight contamination by organic matter, their getter performance will be partially or completely lost, requiring re-activation at high temperatures; TiZr getter membranes typically exhibit a columnar crystalline structure with nanoscale pores, making the inner wall of the vacuum chamber surface porous, unable to effectively block hydrogen diffusion from the substrate material; and vacuum pipes equipped only with TiZr getter membranes cannot maintain a high vacuum level in the vacuum system for extended periods. Summary of the Invention

[0004] This invention aims to solve the technical problems existing in related technologies. To this end, this invention proposes a method for preparing a composite getter membrane on the inner wall of a vacuum pipe and a vacuum pipe in general. By setting a double-layer structure with an Ag functional membrane as the surface layer and a TiZr getter membrane as the bottom layer, the pores of the Ag functional membrane relative to the TiZr getter membrane are sealed to improve the stability of the vacuum chamber and extend the maintenance cycle of the vacuum system.

[0005] In a first aspect, the present invention provides a method for preparing a composite getter membrane on the inner wall of a vacuum pipe, comprising: The vacuum pipeline is pretreated and installed inside the solenoid of the magnetron sputtering coating device. The TiZr filament target and the Ag target are installed inside the vacuum pipeline at the same time. A TiZr getter film was deposited on the inner wall of a vacuum pipe using a magnetron sputtering coating process. An Ag functional film was deposited on the side of the TiZr getter film away from the vacuum pipe using a magnetron sputtering deposition process. In-situ activation of TiZr getter membrane and Ag functional membrane.

[0006] According to the present invention, a method for preparing a composite getter film on the inner wall of a vacuum pipe includes the following specific steps for depositing a TiZr getter film on the inner wall of the vacuum pipe using a magnetron sputtering deposition process: Evacuate the vacuum pipeline to establish a base pressure less than or equal to 5 × 10⁻⁶. -4 A vacuum environment of Pa; Argon gas is introduced into the vacuum pipeline, and the sputtering pressure is maintained between 0.2 Pa and 1 Pa. The solenoid is activated to generate an axial magnetic field, and the strength of the magnetic field is controlled between 150 Gauss and 400 Gauss. A DC negative bias voltage is applied to the TiZr filament target to excite magnetron sputtering, and the control voltage value is between -400V and -700V.

[0007] According to the present invention, a method for preparing a composite getter membrane on the inner wall of a vacuum pipe is provided, wherein the atomic ratio of Ti to Zr in the TiZr filament target is between 40:60 and 60:40.

[0008] According to the present invention, a method for preparing a composite getter membrane on the inner wall of a vacuum pipe is provided, wherein the thickness of the TiZr getter membrane is between 0.5 μm and 2.0 μm.

[0009] According to the present invention, a method for preparing a composite getter film on the inner wall of a vacuum pipe, wherein the deposition of an Ag functional film on the side of the TiZr getter film opposite to the vacuum pipe using a magnetron sputtering deposition process includes: Maintain the vacuum environment inside the vacuum pipe, and switch the target for applying DC negative bias from TiZr filament target to Ag target, and control the voltage value between -300V and -600V.

[0010] According to the present invention, a method for preparing a composite getter membrane on the inner wall of a vacuum pipe is provided, wherein the thickness of the Ag functional membrane is between 50 nm and 200 nm.

[0011] According to the present invention, a method for preparing a composite getter membrane on the inner wall of a vacuum pipe is provided, wherein a TiZr getter membrane and an Ag functional membrane are continuously prepared within the same vacuum cycle.

[0012] According to the present invention, a method for preparing a composite getter membrane on the inner wall of a vacuum pipe, wherein the in-situ activation of the TiZr getter membrane and the Ag functional membrane includes: Vacuum pipes with deposited TiZr getter film and Ag functional film were baked in a vacuum environment with controlled temperature, with the baking temperature controlled between 280℃ and 320℃. Then, heat preservation is carried out, and the heat preservation time is controlled between 20 and 48 hours.

[0013] According to the present invention, a method for preparing a composite getter membrane on the inner wall of a vacuum pipe includes pretreatment of the vacuum pipe comprising: First, clean the inner wall surface of the vacuum pipe to remove the inert barrier layer; Then, surface-active sites are created on the inner wall surface of the vacuum pipe through physical or chemical methods to enhance the adhesion of the coating to the inner wall.

[0014] Secondly, the present invention also provides a vacuum pipe, wherein the inner wall of the vacuum pipe is provided with a composite gas-absorbing membrane, and the composite gas-absorbing membrane is made by any of the methods described above for preparing a composite gas-absorbing membrane on the inner wall of the vacuum pipe.

[0015] The above-described one or more technical solutions of this invention have at least one of the following technical effects: In this invention, TiZr getter membrane and Ag functional membrane are sequentially attached to the inner wall of a vacuum pipe, so that the inner wall of the vacuum pipe forms a double-layer structure with Ag functional membrane as the surface layer and TiZr getter membrane as the bottom layer. The pores of the Ag functional membrane relative to the TiZr getter membrane can be used to seal the vacuum chamber, thereby improving the stability of the vacuum chamber and extending the maintenance cycle of the vacuum system.

[0016] In addition to the technical problems solved by the present invention, the technical features of the technical solutions constituted by the present invention, and the advantages brought about by the technical features of these technical solutions as described above, other technical features of the present invention and the advantages brought about by these technical features will be further explained in conjunction with the accompanying drawings, or will be learned through the practice of the present invention. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a method for preparing a composite getter membrane on the inner wall of a vacuum pipe, provided in an embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of the apparatus for preparing the composite getter membrane provided in an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of the composite getter membrane attached to a vacuum pipe according to an embodiment of the present invention.

[0021] Figure label: 1. Vacuum piping; 2. Solenoid; 3. TiZr target; 4. Ag target; 5. Sealing flange; 6. Auxiliary vacuum chamber; 7. Measuring element; 8. Inlet valve; 9. Pumping unit. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0023] In an embodiment of the present invention, a method for preparing a composite getter membrane on the inner wall of a vacuum pipe is described.

[0024] like Figure 3 As shown, the structure of the composite getter membrane on the inner wall of vacuum pipe 1 is as follows: the bottom layer is a TiZr getter membrane, and the surface layer is an Ag functional membrane. Figure 2 As shown, the magnetron sputtering coating apparatus for preparing composite getter films includes a solenoid 2, a TiZr target 3, an Ag target 4, a sealing flange 5, an auxiliary vacuum chamber 6, a measuring element 7, an inlet valve 8, and a pumping unit 9. The central axis of the vacuum pipe 1 coincides with the central axis of the solenoid 2 to ensure that the central axis of the vacuum pipe 1 is parallel to the axial magnetic field generated by the solenoid 2.

[0025] The method for preparing a composite getter membrane on the inner wall of vacuum pipe 1 includes the following steps: S1. Pre-treat the vacuum pipe 1, install the vacuum pipe 1 inside the solenoid 2 of the magnetron sputtering coating device, and simultaneously install the TiZr filament target and the Ag target inside the vacuum pipe 1.

[0026] Pretreatment includes cleaning the inner wall surface of vacuum pipe 1 to remove inert barrier layers and ensure good cleanliness. This includes physical contaminants such as oxide layers, oil stains, and adsorbed water vapor, as well as chemically adsorbed layers. Common cleaning methods include electropolishing, ultrasonic cleaning, chemical cleaning (such as acid washing and alkaline washing), and vacuum baking for degassing.

[0027] The pretreatment also includes: surface activation treatment of the inner wall of the vacuum pipe 1, which creates surface active sites on the inner wall surface of the vacuum pipe 1 by physical or chemical means. This can significantly enhance the adhesion between the subsequently deposited film layer and the substrate, thereby ensuring that the composite film layer has high stability and durability, and preventing the composite film layer from peeling off due to stress or thermal shock during use.

[0028] Surface activation can be achieved in various ways. For example, wet chemical cleaning (such as ultrasonic cleaning and acid pickling) and dry physical cleaning (such as argon ion etching, glow discharge cleaning, and plasma cleaning) can be used. Surface activation can also be achieved through argon ion bombardment (plasma cleaning) or surface roughening treatment.

[0029] Preferably, the inner wall of an oxygen-free copper vacuum tube, approximately 2 meters long and 150 millimeters in inner diameter, is subjected to electrolytic polishing and ultrasonic cleaning.

[0030] Furthermore, after pretreatment, the vacuum pipe 1 is installed inside the solenoid 2 of the magnetron sputtering coating apparatus. The TiZr filament target and the Ag target are simultaneously installed inside the vacuum pipe 1. This installation method ensures uniform and efficient radial sputtering coating on the inner wall of the long, straight pipe.

[0031] Preferably, the TiZr filament target is a straight rod structure made by winding Ti filaments and Zr filaments.

[0032] S2. A TiZr getter film is deposited on the inner wall of the vacuum pipe 1 using a magnetron sputtering deposition process. This step involves depositing a TiZr getter film on the pretreated inner wall of the vacuum pipe 1. The specific deposition steps include: S21. Evacuate vacuum pipe 1 to establish a base pressure less than or equal to 5 × 10⁻⁶. -4 The vacuum environment is maintained at such a high level to remove residual gases and impurities from the vacuum chamber to the greatest extent possible, ensuring the purity of the deposited film and preventing impurity atoms from being incorporated into the TiZr getter film, thus affecting its getter performance and electrical properties.

[0033] S22. High-purity argon gas is introduced into vacuum pipe 1, and the sputtering pressure is maintained between 0.2 Pa and 1 Pa. Argon gas acts as the sputtering gas; its atoms bombard the surface of the TiZr filament target, causing it to sputter atoms. Precise control of the sputtering pressure optimizes the mean free path of the sputtered particles, thereby regulating the energy and motion direction of the deposited atoms, affecting the film density, grain size, and surface roughness, resulting in excellent getter performance for the TiZr getter film.

[0034] S23. Start solenoid 2 to generate an axial magnetic field and control the strength of the magnetic field between 150 Gauss and 400 Gauss. The axial magnetic field helps to confine plasma electrons, extend their movement path near the target, thereby increasing the probability of collision between electrons and argon atoms, improving ionization efficiency, stabilizing discharge, and effectively improving target utilization and deposition rate, ensuring film uniformity.

[0035] S24. Apply a DC negative bias voltage to the TiZr filament target to excite magnetron sputtering, and control the voltage value between -400V and -700V.

[0036] Understandably, an appropriate negative bias can accelerate the bombardment of the target by argon ions, thereby modulating the energy and kinetic energy of the deposited atoms, which in turn affects the microstructure of the film, such as grain orientation, density, and internal stress, ultimately optimizing the getter performance of the TiZr getter film.

[0037] By adopting the above steps, a highly active TiZr getter film can be formed on the inner wall of vacuum pipe 1. After activation, the TiZr getter film can provide a strong distributed pumping speed for active gases such as H2, CO, CO2, and N2 at room temperature, thereby significantly reducing the static outgassing rate of vacuum pipe 1 and greatly improving the ultimate vacuum level of vacuum pipe 1, which is the key to achieving an ultra-high vacuum environment.

[0038] S3. An Ag functional film is deposited on the side of the TiZr getter film away from the vacuum pipe 1 using a magnetron sputtering deposition process. This step involves depositing a thin and dense Ag functional film on the surface of the already deposited TiZr getter film, using the Ag functional film as a surface layer to eliminate the surface porosity defects of the TiZr getter film.

[0039] The surface and bulk diffusion rates of reactive gas molecules (such as CO and H2) in Ag functional membranes are much higher than the reverse diffusion rates of metal ions (such as Ti and Zr) in Ag functional membranes. This makes Ag functional membranes a "selective permeability membrane": allowing small-molecule reactive gases to penetrate inward and react with the TiZr getter membrane to be removed; at the same time, it effectively blocks the outward migration of Ti and Zr atoms and physically seals the pores of the TiZr getter membrane, greatly suppressing gas permeation from the vacuum pipe material (such as stainless steel).

[0040] The specific deposition steps for Ag functional membranes include: S31. Maintain the vacuum environment in vacuum pipe 1 and switch the target for applying DC negative bias from TiZr filament target to Ag target.

[0041] Preferably, the purity of the Ag target is greater than or equal to 99.99%.

[0042] S32. Start solenoid 2 to generate an axial magnetic field and control the strength of the magnetic field between 150 Gauss and 400 Gauss.

[0043] S33. Apply a DC negative bias voltage to the Ag target to excite magnetron sputtering, and control the voltage value to be between -300V and -600V.

[0044] Thus, a continuous and dense Ag functional film is attached to the surface of the TiZr getter membrane. The thickness of the Ag functional film is between 50 nm and 200 nm. This thickness range is crucial for the Ag functional film to function as a "selective permeation membrane." If the thickness is too thin, a continuous and dense film layer may not be formed, resulting in poor physical sealing effect; if the thickness is too thick, it will significantly increase the diffusion resistance of the active gas to the TiZr getter membrane, reducing pumping efficiency.

[0045] Preferably, the thickness of the Ag functional membrane is between 100 nm and 150 nm. This thickness ensures that the Ag functional membrane completely covers the pores of the TiZr getter membrane, while not hindering the diffusion and transport of active gas to the TiZr getter membrane.

[0046] By adopting the above steps, a double-layer composite membrane with "porous getter as the bottom layer + dense metal as the surface layer" can be formed.

[0047] In addition, as a low resistivity metal, Ag functional film can significantly reduce the beam impedance of the inner wall of vacuum pipe 1 by using Ag functional film as the surface layer of vacuum pipe 1, which has a positive impact on the operation of high-quality beam of particle accelerator.

[0048] Preferably, the TiZr getter membrane and the Ag functional membrane are fabricated continuously within the same vacuum cycle. This minimizes interfacial contamination and ensures the excellent bonding performance of the bilayer membrane. It also prevents the two membranes from being re-exposed to the atmosphere or introducing impurities between fabrication steps, thereby improving the composite getter performance of the bilayer membrane.

[0049] S4. In-situ activation of the TiZr getter membrane and Ag functional membrane. This step is a key process in the preparation of the composite getter membrane. The specific activation process includes: The vacuum pipe 1, which has been deposited with TiZr getter film and Ag functional film, is baked in a vacuum environment under controlled temperature.

[0050] First, the baking temperature is controlled between 280℃ and 320℃ for degassing. Using this temperature range to bake the TiZr getter membrane and Ag functional membrane in vacuum pipe 1 can effectively remove water molecules and other volatile impurities adsorbed on the membrane surface and pores, preparing for subsequent activation at higher temperatures and avoiding a decrease in vacuum due to the release of a large amount of gas during the activation process.

[0051] Then, heat preservation is performed, and the heat preservation time is controlled between 20 and 48 hours. Preferably, the heat preservation time is 24 hours.

[0052] It is understandable that the baking process can optimize the microstructure inside the Ag functional membrane and promote the diffusion and transport rate of active gases (such as H2 and CO) in the Ag functional membrane, so that they can effectively diffuse through the Ag functional membrane to the TiZr getter membrane and be chemically adsorbed.

[0053] In-situ activation of the composite getter membrane can ensure that the bilayer membrane structure can exert the maximum synergistic effect of "internal absorption and external sealing", forming a selective permeation channel, achieving better ultimate vacuum, lower static and dynamic desorption rates, and extending the maintenance cycle of the system.

[0054] Based on the above embodiments, another embodiment of the present invention introduces a method for preparing a composite getter membrane on the inner wall of a vacuum pipe.

[0055] When depositing a TiZr getter film using magnetron sputtering, a TiZr filament target with an atomic ratio of Ti:Zr between 40:60 and 60:40 is used.

[0056] Choosing this atomic ratio optimizes the crystal structure and electronic properties of the TiZr getter film, enabling it to have the best adsorption capacity and rate for active gases, especially hydrogen and carbon monoxide, after activation, thus ensuring high-efficiency getter performance.

[0057] Furthermore, to ensure that the getter capacity of the TiZr getter membrane can meet the vacuum maintenance requirements of the vacuum pipeline 1 during long-term operation, its thickness needs to be greater than a specific value. However, if the thickness of the TiZr getter membrane is too large, it will also lead to excessive internal stress between the membrane layer and the pipe wall and a decrease in adhesion.

[0058] Therefore, the thickness of the TiZr getter film should be controlled between 0.5 μm and 2.0 μm during the deposition process. Within this thickness range, the TiZr getter film exhibits a stable film structure and excellent getter performance.

[0059] Furthermore, the surface activation treatment of the inner wall of the vacuum pipe 1 specifically includes: firstly, cleaning the surface of the inner wall of the vacuum pipe 1 to remove the inert barrier layer; then, creating surface-active sites on the surface of the inner wall of the vacuum pipe 1 through physical or chemical methods to enhance the adhesion of the coating to the inner wall of the vacuum pipe 1. For example, the inner wall of the pipe can be treated by argon ion bombardment. By bombarding the surface with high-energy argon ions, surface atoms are removed, forming a micro-rough structure and dangling bonds, which significantly increases the mechanical interlocking and chemical bonding between the film and the substrate, thereby greatly improving the adhesion strength of the film and effectively preventing the film from peeling off during use.

[0060] In addition, in another embodiment of the present invention, a vacuum conduit is described.

[0061] Vacuum pipe 1 is provided with a composite getter membrane consisting of an Ag functional membrane and a TiZr getter membrane. The composite getter membrane is prepared using the method described in the above embodiments for preparing a composite getter membrane on the inner wall of vacuum pipe 1.

[0062] like Figure 3 As shown, the structure of the composite getter membrane on the inner wall of vacuum pipe 1 is as follows: the bottom layer is a TiZr getter membrane, and the top layer is an Ag functional membrane. This vacuum pipe 1 combines the dense barrier properties of the Ag functional membrane with the strong getter capacity of the TiZr getter membrane.

[0063] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0064] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0065] In embodiments of the present invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0066] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms are not limited to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a composite getter membrane on the inner wall of a vacuum pipe, characterized in that, include: The vacuum pipeline is pretreated and installed inside the solenoid of the magnetron sputtering coating device. The TiZr filament target and the Ag target are installed inside the vacuum pipeline at the same time. A TiZr getter film was deposited on the inner wall of a vacuum pipe using a magnetron sputtering coating process. An Ag functional film was deposited on the side of the TiZr getter film away from the vacuum pipe using a magnetron sputtering deposition process. In-situ activation of TiZr getter membrane and Ag functional membrane.

2. The method for preparing a composite getter membrane on the inner wall of a vacuum pipe according to claim 1, characterized in that, The specific steps for depositing a TiZr getter film on the inner wall of a vacuum pipeline using magnetron sputtering deposition technology include: Evacuate the vacuum pipeline to establish a base pressure less than or equal to 5 × 10⁻⁶. -4 A vacuum environment of Pa; Argon gas is introduced into the vacuum pipeline, and the sputtering pressure is maintained between 0.2 Pa and 1 Pa. The solenoid is activated to generate an axial magnetic field, and the strength of the magnetic field is controlled between 150 Gauss and 400 Gauss. A DC negative bias voltage is applied to the TiZr filament target to excite magnetron sputtering, and the control voltage value is between -400V and -700V.

3. The method for preparing a composite getter membrane on the inner wall of a vacuum pipe according to claim 2, characterized in that, In TiZr filamentary targets, the atomic ratio of Ti to Zr is between 40:60 and 60:

40.

4. The method for preparing a composite getter membrane on the inner wall of a vacuum pipe according to claim 3, characterized in that, The thickness of the TiZr getter film ranges from 0.5 μm to 2.0 μm.

5. The method for preparing a composite getter membrane on the inner wall of a vacuum pipe according to any one of claims 1 to 4, characterized in that, The deposition of an Ag functional film on the side of the TiZr getter film away from the vacuum channel using a magnetron sputtering deposition process includes: Maintain the vacuum environment inside the vacuum pipe, and switch the target for applying DC negative bias from TiZr filament target to Ag target, and control the voltage value between -300V and -600V.

6. The method for preparing a composite getter membrane on the inner wall of a vacuum pipe according to claim 5, characterized in that, The thickness of Ag functional films ranges from 50 nm to 200 nm.

7. The method for preparing a composite getter membrane on the inner wall of a vacuum pipe according to claim 6, characterized in that, TiZr getter membrane and Ag functional membrane are continuously fabricated within the same vacuum cycle.

8. The method for preparing a composite getter membrane on the inner wall of a vacuum pipe according to claim 5, characterized in that, The in-situ activation of the TiZr getter membrane and Ag functional membrane includes: Vacuum pipes with deposited TiZr getter film and Ag functional film were baked in a vacuum environment with controlled temperature, with the baking temperature controlled between 280℃ and 320℃. Then, heat preservation is carried out, and the heat preservation time is controlled between 20 and 48 hours.

9. The method for preparing a composite getter membrane on the inner wall of a vacuum pipe according to claim 5, characterized in that, The pretreatment of the vacuum pipeline includes: First, clean the inner wall surface of the vacuum pipe to remove the inert barrier layer; Then, surface-active sites are created on the inner wall surface of the vacuum pipe through physical or chemical methods to enhance the adhesion of the coating to the inner wall.

10. A vacuum pipe, characterized in that, The inner wall of the vacuum pipe is provided with a composite gas-suction membrane, which is made by the method for preparing a composite gas-suction membrane on the inner wall of the vacuum pipe as described in any one of claims 1 to 9.

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