Packaging method of getter and getter

Abstract

The invention discloses a getter packaging method and a getter, and belongs to the technical field of getters, in the getter packaging method, firstly, a getter material is placed in a metal pipe, then the end, with an opening, of the metal pipe is machined to form a narrowing part, a concave-convex structure is formed on the inner wall of the narrowing part, and the getter material is packaged in the narrowing part. The method comprises the following steps of: narrowing a metal pipe in a concave-convex structure, placing a sealing material in the narrowing part, fixing the sealing material in the concave-convex structure, placing the metal pipe in which an air suction material and the sealing material are placed in a vacuum environment, heating the metal pipe, melting the sealing material and realizing flowability, so that the narrowing part can be filled with the sealing material to form a sealing layer; by the adoption of the packaging method, the gap space needing to be sealed can be reduced, fine sealing materials can be clamped in the narrowing part through the concave-convex structure, therefore, the using amount of the sealing materials can be reduced, the temperature needed in the machining process can be reduced, the machining yield is increased, and the machining cost can be reduced.

Description

Technical Field

[0001] This invention relates to the technical field of getters, and in particular to a method for encapsulating a getter and a getter itself. Background Technology

[0002] Getters can further reduce the pressure of the vacuum environment and maintain it long-term when vacuum pump units cannot achieve higher vacuum levels or ensure equipment sealing. In related technologies, getter manufacturing typically involves treating the getter components under pressure lower than the operating pressure using a sealable shell, such as heating, and then sealing under low pressure. To ensure a good seal, a large amount of sealing material is required, and the total volume of the sealing material is much larger than the volume needed to seal the gap, resulting in high material consumption and increased costs. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention proposes a method for encapsulating a getter and a getter that can effectively reduce the amount of sealing material used, thereby reducing the cost of the processing.

[0004] A method for encapsulating a getter according to a first aspect of the present invention includes: An air-absorbing material is placed inside a metal tube, wherein at least one end of the metal tube has an opening; The end of the metal tube with the opening is processed to form a narrow section. The inner diameter of the narrow section is smaller than the inner diameter of the metal tube, and the inner wall of the narrow section has a concave-convex structure. A sealing material is placed in the narrow section and fixed in the concave-convex structure. The metal tube containing the air-absorbing material and the sealing material is placed in a vacuum environment; In the vacuum environment, the metal tube is heated, and the heating temperature is controlled to reach a first preset temperature and maintained for a first preset time, so that the sealing material melts and fills the narrowed part to form a sealing layer. The first preset temperature is greater than the melting temperature of the sealing material and less than the melting temperature of the air-absorbing material.

[0005] The encapsulation method for getter according to embodiments of the present invention has at least the following beneficial effects: Using a metal tube as the outer shell, a suction material is first placed inside the metal tube. The metal tube can be a tubular structure with one or both ends open. Then, the open end of the metal tube is processed to form a narrow section, causing the inner diameter of the metal tube to shrink at the narrow section, i.e., the inner diameter of the narrow section is smaller than the inner diameter of the metal tube. At the same time, an uneven structure is formed on the inner wall of the narrow section, i.e., the inner wall of the narrow section is a non-smooth wall surface. A sealing material is placed inside the narrow section and fixed in the uneven structure. Then, the metal tube containing the suction material and the sealing material is placed in a vacuum environment and heated. The heating temperature is controlled to reach a first preset temperature and maintained for a first preset time, so that the sealing material melts and becomes flowable. In this way, the sealing material can fill the narrow section and form a sealing layer. The first preset temperature is higher than the melting temperature of the sealing material but lower than the melting temperature of the suction material to avoid the temperature being too high and affecting the stability of the suction material. The above-mentioned encapsulation method can reduce the required sealing gap space, and the small sealing material can be clamped inside the narrowed part by the concave and convex structure, thereby reducing the amount of sealing material used, which can also reduce the temperature required for the processing and improve the processing yield, thus helping to reduce processing costs.

[0006] According to some embodiments of the present invention, in the vacuum environment, before heating the metal tube and controlling the heating temperature to reach a first preset temperature and maintain it for a first preset time, the encapsulation method further includes: The metal pipe is heated, and the heating temperature is controlled to reach a second preset temperature and maintained for a second preset time, so that the gas inside the gas-absorbing material can be released in a vacuum environment. The second preset temperature is lower than the melting temperature of the sealing material.

[0007] According to some embodiments of the present invention, the step of processing the end of the metal tube having the opening to form a narrowed portion includes: The metal tube is squeezed near the opening to narrow the tube body and form the narrowed portion. The concave-convex structure is integrally formed with the narrowed portion, or the concave-convex structure is formed on the inner wall of the narrowed portion after the narrowed portion is formed.

[0008] According to some embodiments of the present invention, the extrusion of the metal tube near the opening includes: The outer wall of the metal tube is extruded along the radial direction of the metal tube, causing the outer wall of the metal tube to be concave to form an annular groove. The concave-convex structure is formed on the inner wall of the narrowed portion and is arranged away from the bottom wall of the annular groove. The annular groove has two opposite side walls that are inclined toward the axis of the metal tube, so that the annular groove gradually narrows from the outside to the inside; the inner wall of the metal tube has a first end face and a second end face, and the narrowing part is located between the first end face and the second end face.

[0009] According to some embodiments of the present invention, the packaging method further includes: Before the air-absorbing material is placed inside the metal pipe, the metal pipe is processed so that one end of the metal pipe has the opening and the other end forms a closed bottom. After the narrowed portion is formed by processing the end of the metal tube with the opening, the first end face faces the bottom of the metal tube, so that a receiving cavity is formed between the first end face and the bottom of the metal tube, and the first end face can prevent the air-absorbing material from entering the narrowed portion.

[0010] According to some embodiments of the present invention, placing air-absorbing material inside the metal tube includes: the amount of air-absorbing material is sufficient to fill the receiving cavity after the narrowing portion is formed.

[0011] According to some embodiments of the present invention, the outer diameter of the metal pipe is greater than or equal to 3 mm, the wall thickness of the metal pipe is less than or equal to 1 mm, and the length of the metal pipe is greater than the outer diameter of the metal pipe. And / or, the distance between the narrowed portion and the opening ranges from 2mm to 20mm, and the length of the narrowed portion ranges from 3mm to 20mm.

[0012] According to some embodiments of the present invention, the sealing material is a granular or sheet-like glassy structure, and the average length dimension of the sealing material is greater than the maximum inner diameter enclosed by the concave-convex structure; And / or, the melting temperature range of the sealing material is 300°C to 500°C; And / or, the air-absorbing material is a powder or granular material with air-absorbing capacity; And / or, the metal tubing is made of any one of iron, aluminum, or copper, or an alloy of iron, aluminum, or copper.

[0013] According to some embodiments of the present invention, the packaging method further includes: The sealing material is pretreated at a third preset temperature and maintained for a third preset time to form the sealing material. The third preset temperature is greater than the melting temperature of the sealing material and the difference ranges from 50°C to 200°C.

[0014] According to some embodiments of the present invention, after the sealing material is melted and filled into the narrowed portion to form a sealing layer, the encapsulation method further includes: The heating temperature is controlled to be reduced from the first preset temperature to the ambient temperature, so that the sealing layer solidifies; The pressure in the vacuum environment is increased to atmospheric pressure to complete the preparation of the getter.

[0015] According to a second aspect of the present invention, a getter includes a metal tube having an opening at at least one end, a narrowing portion having an inner diameter smaller than the inner diameter of the metal tube, and an uneven structure formed on the inner wall of the narrowing portion; a sealing layer is filled in the narrowing portion, the sealing layer being formed by melting a sealing material placed within the uneven structure.

[0016] The getter according to embodiments of the present invention has at least the following beneficial effects: The getter uses a metal tube as its outer shell. The metal tube can be a tubular structure with one or both ends open. The open end of the metal tube has a narrowed section with an inner diameter smaller than that of the metal tube. Simultaneously, an uneven structure is formed on the inner wall of the narrowed section, meaning the inner wall is not smooth. The sealing material is fixed within this uneven structure. An encapsulation method is used to process the metal tube, melting and filling the narrowed section with the sealing material to form a sealing layer. This reduces the required sealing gap and allows for the clamping of small amounts of sealing material within the narrowed section via the uneven structure, thus reducing the amount of sealing material used. This also lowers the processing temperature and increases the yield rate, ultimately reducing the cost of the getter.

[0017] According to some embodiments of the present invention, the outer diameter of the metal pipe is greater than or equal to 3 mm, the wall thickness of the metal pipe is less than or equal to 1 mm, and the length of the metal pipe is greater than the outer diameter of the metal pipe. And / or, the distance between the narrowed portion and the opening ranges from 2mm to 20mm, and the length of the narrowed portion ranges from 3mm to 20mm; And / or, the metal tubing is made of any one of iron, aluminum, or copper, or an alloy of iron, aluminum, or copper.

[0018] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0019] Figure 1 This is a schematic flowchart of a method for encapsulating a getter according to an embodiment of the present invention; Figure 2 This is a schematic flowchart of a method for encapsulating a getter according to another embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a metal tube according to an embodiment of the present invention before processing; Figure 4 This is a schematic diagram of a metal tube with a narrowed section formed according to an embodiment of the present invention; Figure 5 This is a schematic diagram of a structure in which an air-absorbing material and a sealing material are placed inside a metal tube according to an embodiment of the present invention; Figure 6 This is a partial structural diagram of the narrowed portion in a metal tube according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of a metal pipe in a heated state at a second preset temperature according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the forming state of the sealing layer in a metal pipe according to an embodiment of the present invention; Figure 9 This is a flowchart illustrating a specific example of a method for encapsulating a getter according to an embodiment of the present invention.

[0020] Figure label: Metal tube 100; opening 110; narrowing section 120; narrow space 121; annular groove 130; first end face 131; second end face 132; concave-convex structure 140; protrusion 141; recess 142; receiving cavity 150; 200g of air-absorbing material; Sealing material 300; sealing layer 310. Detailed Implementation

[0021] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0022] In the description of this invention, it should be understood that the terms "axial", "radial", "circumferential", "upper", "lower", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this 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, and therefore should not be construed as a limitation of this invention.

[0023] In the description of this invention, the terms "first" and "second" are used only to distinguish technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or implicitly indicating the order of the technical features indicated.

[0024] In the description of this invention, it should be noted that terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are some embodiments of the present invention, not all embodiments.

[0026] In the vacuum industry, getters are crucial. They can further reduce the pressure of the vacuum environment and maintain it long-term when vacuum pumps cannot achieve higher vacuum levels or when equipment sealing is difficult. In getter manufacturing, the getter components are typically treated with a sealable shell at a pressure lower than the operating pressure, such as through heating, and then sealed under low pressure. Getters produced in this way are activated under operating conditions, allowing the internal getter material to function and further reduce the vacuum level.

[0027] Currently, the sealable shells used for getter encapsulation are typically made of metal to ensure the getter's tightness. The sealable shell can be made of a heat-melting and flowable sealing material. This sealing material usually has a high melting temperature and needs to soften and flow before it can seal the shell. Therefore, the actual processing temperature (softening and flow temperature) is much higher than the apparent melting point of the sealing material.

[0028] Therefore, the encapsulation methods in related technologies have the following problems: the getter needs to be encapsulated at a high temperature, and the getter material will be damaged due to melting or collapse of the microporous structure; in order to ensure the sealing yield, a large amount of sealing material is required, and the total volume of the sealing material is much larger than the required volume of the gap to ensure sufficient cross-section, but this will result in a large consumption of sealing material, and high-temperature encapsulation requires higher energy consumption, which increases the production cost of the getter.

[0029] To address the aforementioned issues, this invention proposes a getter encapsulation method and getter, which can reduce the amount of sealing material 300 used, lower the temperature required for the processing, increase the yield of processed products, and reduce manufacturing costs.

[0030] Reference Figure 1 As shown, some embodiments of the present invention provide a method for encapsulating a getter, including: Step S100: Place the air-absorbing material 200 into the metal tube 100; In step S200, the end of the metal tube 100 with the opening 110 is processed to form a narrowed portion 120, and the inner wall of the narrowed portion 120 is formed with a concave-convex structure 140. A sealing material 300 is placed in the narrowed portion 120 and the sealing material 300 is fixed in the concave-convex structure 140. Step S300: The metal tube 100 containing the suction material 200 and the sealing material 300 is placed in a vacuum environment; In step S400, the metal tube 100 is heated in a vacuum environment, and the heating temperature is controlled to reach a first preset temperature and maintained for a first preset time, so that the sealing material 300 melts and fills the narrowed part 120 to form a sealing layer 310.

[0031] It is understandable that the getter uses a metal tube 100 as its outer shell. The metal tube 100 can be a tubular structure with a single-end opening 110 or a tubular structure with double-end openings 110. (Refer to...) Figure 3 As shown, taking a metal tube 100 with a single-end opening 110 as an example, one end of the metal tube 100 is an opening 110 and the other end is a closed bottom. A receiving cavity 150 is formed inside the metal tube 100. First, the suction material 200 is put into the receiving cavity 150 through the opening 110 and the suction material 200 is placed at the bottom of the metal tube 100.

[0032] In some embodiments, the metal tube 100 is a hollow, straight tube, which facilitates processing. For example, the straight metal tube 100 is easily fixed on processing equipment for processing operations. In other embodiments, the metal tube 100 can be a curved tube, and the specific shape can be selected according to the application requirements. It should be noted that the gas-absorbing material 200 can be a powdered or granular material with gas-absorbing capacity under low pressure, such as a silicon-based molecular sieve, Cu-ZSM-5 molecular sieve, etc., which can be selected according to the application requirements.

[0033] It should be noted that in some embodiments, when the metal tube 100 is a tube with two openings 110 at both ends, during manufacturing, one opening 110 at one end of the metal tube 100 can be processed first to form a closed bottom, and then the opening 110 at the other end can be processed to form a narrowed portion 120.

[0034] In some other embodiments, when the metal tube 100 is a tube with openings 110 at both ends, narrowing portions 120 can be made at both ends of the metal tube 100. Specifically, the air-absorbing material 200 is first placed in the middle of the metal tube 100, and then the narrowing portions 120 are formed at both ends of the metal tube 100 near the openings 110 using the operation of step S200 described above.

[0035] Reference Figure 4 As shown, in step S200, the narrowing portion 120 is formed on the metal tube 100 near the opening 110, and the narrowing portion 120 is located between the opening 110 and the bottom. After the narrowing portion 120 is formed, the inner diameter of the narrowing portion 120 is smaller than the inner diameter of the metal tube 100, causing the inner diameter of the metal tube 100 near the opening 110 to shrink. That is, the position where the narrowing portion 120 is located in the inner cavity of the metal tube 100 is narrower than other positions. The narrowing portion 120 can be understood as a slit structure inside the metal tube 100.

[0036] Reference Figure 5 and Figure 6 As shown, in the embodiment, during the processing of the narrowing portion 120, an uneven structure 140 is formed on the inner wall of the narrowing portion 120. The uneven structure 140 can be understood as a structure in which protrusions 141 and depressions 142 are alternately distributed on the inner wall of the narrowing portion 120; that is, the inner wall of the narrowing portion 120 is a non-smooth surface. Specifically, the uneven structure 140 can have a wavy, sawtooth, or spiral cross-section, with the protrusions 141 and depressions 142 distributed in a regular pattern. Taking a wavy structure as an example, the peaks are protrusions 141, and the troughs between adjacent peaks form depressions 142. The peaks and troughs are alternately distributed on the inner wall of the narrowing portion 120, thus forming the uneven structure 140. In other embodiments, the uneven structure 140 can also be a structure with irregularly distributed protrusions 141 and depressions 142, for example, the inner wall surface of the narrowing portion 120 may have irregular uneven textures.

[0037] Understandably, since the inner wall of the narrowing portion 120 has an added concave-convex structure 140, when the sealing material 300 is placed in the narrowing portion 120, the concave-convex structure 140 can increase the friction of the inner wall, so that the sealing material 300 can be fixed in the concave-convex structure 140. The sealing material 300 can be in powder or granule form, so that the sealing material 300 can be restricted to the position of the recess 142.

[0038] Since the getter needs to be encapsulated in a low-pressure environment, after the getter material 200 and sealing material 300 are placed inside the metal tube 100, the metal tube 100 is placed in a vacuum environment for further processing. This vacuum environment can be a vacuum device with a working space. The metal tube 100 is placed in the working space, and the working space is evacuated. In some embodiments, the preset vacuum degree is 0.001Pa-0.02Pa to ensure that the air in the containment cavity 150 can be effectively discharged.

[0039] In step S400, after reaching a preset vacuum level, the metal pipe 100 containing the suction material 200 and the sealing material 300 is heated in a vacuum environment. The heating temperature is set to a first preset temperature, and the heating is maintained at the first preset temperature for a first preset duration. This first preset temperature is higher than the melting temperature of the sealing material 300 but lower than the melting temperature of the suction material 200. This allows the sealing material 300 to enter a molten state, and the heating temperature will not exceed the melting temperature of the suction material 200, avoiding excessively high temperatures that could affect the stability of the suction material 200. The first preset temperature and the first preset duration can be set according to the specific characteristics of the sealing material 300.

[0040] Reference Figure 8 As shown, it can be understood that under the heating of the first preset temperature, the sealing material 300 melts and flows in the narrowing portion 120, so that the molten sealing material 300 can fill the narrowing portion 120, thereby forming a sealing layer 310 to achieve the purpose of sealing the getter.

[0041] Compared to related technologies that use sealing material 300 to seal the gaps in a sealable housing, the packaging method of this embodiment further processes the area to be sealed to form a narrowing portion 120, reducing the gap space to be sealed. A concave-convex structure 140 is formed inside the narrowing portion 120, which clamps and fixes the small sealing material 300. By using the structure of the narrowing portion 120, the concave-convex structure 140 is added within a smaller gap space, further reducing the size of the gap space and increasing internal friction, thus fixing the sealing material 300 and reducing the likelihood of the sealing material 300 falling into the receiving cavity 150 or detaching towards the opening 110. A small amount of sealing material 300 is sufficient to seal the gap space within the narrowing portion 120, effectively reducing the amount of sealing material 300 used.

[0042] It should be noted that with the reduction in the amount of sealing material 300, the heating time required during processing is also reduced, which helps to reduce energy consumption. Furthermore, with a smaller gap space, the reliability of the sealing layer 310 is also higher, the sealing effect is better, the processing yield is improved, and the processing cost is reduced.

[0043] Reference Figure 2 As shown, some embodiments of the present invention provide a method for encapsulating a getter, including: Step S110: Place the suction material 200 into the bottom of the metal tube 100; Step S210: The metal tube 100 is processed near the opening 110 to form a narrowing portion 120, and the inner wall of the narrowing portion 120 is formed with an uneven structure 140, and a sealing material 300 is placed in the narrowing portion 120. Step S310: Place the metal tube 100 containing the suction material 200 and the sealing material 300 in a vacuum environment; Step S410: After reaching the preset vacuum level, the metal tube 100 is heated, and the heating temperature is controlled to reach the second preset temperature and maintained for the second preset time, so that the gas inside the gas-absorbing material 200 is released. Step S420: Control the heating temperature to rise to a first preset temperature and maintain it for a first preset time, so that the sealing material 300 melts and fills the narrowed portion 120 to form a sealing layer 310. Step S430: Control the heating temperature to be reduced from the first preset temperature to the ambient temperature, so that the sealing layer 310 solidifies; Step S440: Increase the pressure in the vacuum environment to atmospheric pressure to complete the preparation of the getter.

[0044] It is understood that, taking the metal tube 100 with a single-end opening 110 as an example, the operations of steps S110 to S310 are similar to those of steps S100 to S300 in the above embodiment, as detailed in the foregoing description. The main difference between steps S410 to S440 and the above embodiment is that, before heating to form the sealing layer 310, heating is first performed at a second preset temperature so that the gas-absorbing material 200 can fully release the internal gas.

[0045] Specifically, a metal tube 100 containing getter material 200 and sealing material 300 is placed in a working space, and the working space is evacuated. After reaching a preset vacuum level, the entire metal tube 100 containing getter material 200 and sealing material 300 is heated, and the heating temperature is set to a second preset temperature. The heating is carried out at the second preset temperature for a second preset duration. The second preset temperature is lower than the melting temperature of the sealing material 300, meaning that the heating process at the second preset temperature will not cause the sealing material 300 to melt. At this time, due to the low pressure and heating state, the gas inside the getter material 200 can be fully released, reducing the impact of the internal gas on the use effect of the getter material 200 and improving the getter's getter performance.

[0046] Reference Figure 7As shown, since the second preset temperature does not reach the melting temperature of the sealing material 300, there is still a certain gap between the concave-convex structure 140 and the sealing material 300. This gap forms a through channel for ventilation, ensuring that gas can be discharged while the concave-convex structure 140 clamps the sealing material 300. Figure 7 The middle arrow indicates the direction of gas discharge.

[0047] Reference Figure 6 As shown, it should be noted that the sealing material 300 used in the embodiment is a granular or sheet-like glassy structure with bismuth oxide as the main material. Specifically, the granular material can be spherical or other irregular particle shapes. The size of the granular or sheet-like sealing material 300 is small enough to be able to enter the narrowing portion 120, and the sealing material 300 can be confined in the space where the concave-convex structure 140 is located. For example, the granular sealing material 300 can fall into the recess 142 position of the concave-convex structure 140, so that the sealing material 300 is clamped in the concave-convex structure 140.

[0048] In the embodiment, the average length dimension of the sealing material 300 is greater than the inner diameter dimension of the space enclosed within the concave-convex structure 140. When the sealing material 300 is granular, the average length dimension of the sealing material 300 can be understood as the average diameter of all the granules in the sealing material 300. When the sealing material 300 is sheet-like, the average length dimension of the sealing material 300 can be understood as the average length of all the sheet-like bodies.

[0049] Reference Figure 6 As shown, since the concave-convex structure 140 is distributed around the inner wall of the narrowing portion 120, taking the position of the protrusion 141 as a reference, multiple protrusions 141 in the circumferential direction form a roughly circular slit space. The maximum inner diameter d3 of this slit space, and the size of the space enclosed by the concave-convex structure 140, can be understood as the maximum inner diameter d3 of this slit space, that is, within the narrowing portion 120. Taking a sheet-like body as an example, when the average length of the sheet-like body is greater than the aforementioned inner diameter size, and the width of the sheet is less than the aforementioned inner diameter size, the sheet-like sealing material 300 can pass vertically through the slit space. When the sheet-like sealing material 300 is tilted to the side or placed horizontally, the sealing material 300 can be stuck between adjacent protrusions 141, achieving the effect of restricting the sealing material 300.

[0050] Taking the glass frit-like sealing material 300 as an example, the optional glass frit can be pre-treated in a container to obtain the appropriate size required for the sealing material 300. The melting temperature range of the sealing material 300 is 300°C to 500°C. The melting temperature of the getter material 200 is higher than that of the sealing material 300. That is, the first preset temperature can be set between 300°C and 500°C, and the second preset temperature can be set below 300°C to meet the heating requirements of the encapsulation.

[0051] In some embodiments, the sealing material 300 is mainly made of bismuth oxide, and its melting temperature range is preferably in the range of 320°C-450°C, which has a better melting state and meets the flowability requirements. In other embodiments, the heating temperature can be selected in the range of 350°C to 420°C, so that the sealing material 300 can be fully filled in the narrowing portion 120. Therefore, the first preset temperature can preferably be set in the range of 350°C to 420°C, and the second preset temperature can preferably be in the range of 200°C to 250°C. For example, the first preset temperature is set to 380°C and the second preset temperature is set to 250°C, which meets the requirement of fully releasing the gas inside the gas-absorbing material 200.

[0052] It is understandable that, since the sealing material 300 is heated to a molten state and has fluidity, the sealing material 300 will flow into the concave-convex structure 140 and fill the recess 142, thereby forming a sealing layer 310 in the narrowed portion 120. The concave-convex structure 140 will also have a fixing effect on the sealing layer 310, improving the sealing effect.

[0053] Reference Figure 9 As shown, it should be noted that in some embodiments, the encapsulation method further includes: before encapsulating the sealing material 300 into the metal tube 100, the raw material of the sealing material 300 is pretreated to form granular or sheet-like sealing material 300 to expel the gas inside the sealing material 300.

[0054] Specifically, due to the presence of minute gaps and air within the sealing material, the sealing material is heated at a third preset temperature and maintained for a third preset time to allow it to recrystallize. This third preset temperature can be understood as the recrystallization temperature of the sealing material, enabling it to recrystallize into sealing material 300. It is understood that to achieve recrystallization of the sealing material, processing must be performed at a temperature above the melting temperature. Therefore, in this embodiment, the third preset temperature is greater than the melting temperature of the sealing material 300, with the difference between the third preset temperature and the melting temperature of the sealing material 300 ranging from 50°C to 200°C. For example, if the melting temperature of the sealing material 300 is 500°C, the third preset temperature can be set within the range of 550°C to 700°C. After pretreatment, the sealing material 300 achieves good fluidity and wettability within the melting temperature range, and after sufficient expulsion of internal gas, a smooth sealing surface is obtained, which is beneficial for improving the sealing effect.

[0055] It is understandable that in step S430, when the heating temperature decreases from the first preset temperature to the ambient temperature, the sealing layer 310 will change from a molten state to a solidified state, allowing the sealing layer 310 to form and reach a stable state. This ambient temperature can be understood as the indoor ambient temperature or the normal temperature at which the sealing material 300 can solidify.

[0056] In step S440, after the sealing layer 310 solidifies, the pressure in the vacuum environment is increased to atmospheric pressure, i.e., restored to normal atmospheric pressure. The getter can then be removed from the working space, thus completing the preparation of the getter. The prepared getter can be used to externally break the metal tube 100, connecting the space within the receiving cavity 150 with the area requiring increased vacuum, thereby activating the gettering effect of the getter material 200.

[0057] Reference Figure 3 As shown, the metal tubing 100 used in this embodiment of the invention is made of any one of iron, aluminum, or copper, or it can be made of an alloy material. This ensures that the metal tubing 100 has sufficient strength to meet the shell strength requirements of the getter and guarantee its sealing performance. For example, an alloy material with iron, aluminum, or copper as the main components. The metal tubing 100 in this embodiment has a certain degree of flexibility, allowing it to be plastically processed on presses with a capacity of less than 2 tons to change its shape.

[0058] In some embodiments, the metal tube 100 is selected as a hollow tube with an outer diameter greater than or equal to 3 mm and a wall thickness less than or equal to 1 mm, and the length of the metal tube 100 is greater than the outer diameter of the metal tube 100, to meet the shell requirements of the getter and ensure that the metal tube 100 is flexible enough to be plastically processed and changed in shape on a press with a capacity of less than 2 tons.

[0059] In some embodiments, the step S200 described above, which involves processing the end of the metal tube 100 having the opening 110 to form the narrowed portion 120, includes: In step S220, the metal tube 100 is squeezed near the opening 110 to narrow the tube body of the metal tube 100 to form a narrowed portion 120. The concave-convex structure 140 is integrally formed with the narrowed portion 120.

[0060] Understandably, the metal tube 100 can be processed on a press to form a narrowed portion 120. For example, the outer wall of the metal tube 100 can be pressed by a die, which applies radial pressure along the metal tube 100, causing the outer wall of the metal tube 100 to be recessed 142, thereby narrowing the inner cavity of the metal tube 100. Simultaneously with the die extrusion, the metal tube 100 is rotated, forming an annular groove 130 in the recess 142 on the outer peripheral wall of the metal tube 100. This causes the inner portion of the metal tube 100 to narrow at the position corresponding to the annular groove 130, thus forming the narrowed portion 120.

[0061] In some embodiments, the mold has a concave-convex surface opposite to the bottom wall of the annular groove 130. When the mold extrudes the outer wall of the metal tube 100, and the annular groove 130 is formed, the concave-convex surface, by extruding the bottom wall of the annular groove 130, causes the inner wall of the narrowed portion 120 to be correspondingly extruded, forming an alternating concave-convex structure. The concave-convex structure 140 is distributed opposite to the bottom wall of the annular groove 130. It is understood that the concave-convex surface can be wavy, serrated, or other surfaces with concave-convex textures, thereby forming a concave-convex structure 140 of a corresponding shape.

[0062] In other embodiments, a mold with an embossed pattern can be placed inside the narrowing portion 120. While the metal tube 100 is being extruded from the outside, the internal mold also extrudes the inner wall, thereby forming an alternating embossed structure on the inner wall. In other embodiments, after the narrowing portion 120 is formed, an embossed structure 140 can be machined on the inner wall of the narrowing portion 120. The machining method can be selected according to actual needs.

[0063] Reference Figure 5 and Figure 6 As shown, in this embodiment, the opposite side walls of the annular groove 130 are inclined toward the axis of the metal tube 100, the cross-section of the annular groove 130 is trapezoidal, and it gradually narrows from the outside to the inside along the radial direction of the metal tube 100, which makes it easy to process, reduces the risk of the metal tube 100 breaking during the processing, and improves the yield.

[0064] It should be noted that the inner wall of the metal tube 100 has a first end face 131 and a second end face 132 formed at both ends of the narrowing portion 120. The narrowing portion 120 is located between the first end face 131 and the second end face 132. The first end face 131 faces the bottom of the metal tube 100, and a receiving cavity 150 is formed between the first end face 131 and the bottom of the metal tube 100. The second end face 132 faces the opening 110. It can be understood that the first end face 131 and the second end face 132 are both conical surfaces. When the volume of the suction material 200 in the receiving cavity 150 reaches the position of the first end face 131, the first end face 131 can prevent the suction material 200 from moving towards the opening 110. In some embodiments, the suction material 200 may be a granular material, and the diameter of the granular material is larger than the maximum inner diameter of the narrowing portion 120, so that the first end face 131 can block the suction material 200 from entering the narrowing portion 120, effectively isolating the suction material 200 from the sealing material 300.

[0065] It is understood that in some embodiments, since the narrowing portion 120 has a first end face 131 on the side facing the receiving cavity 150, the first end face 131 can block the suction material 200, so that the volume of the suction material 200 can fill the receiving cavity 150 without affecting the sealing quality of the sealing layer 310.

[0066] Reference Figure 6 As shown, the distance between the narrowed portion 120 and the opening 110 is d1, and the length of the narrowed portion 120 is d2. The value of d1 ranges from 2mm to 20mm, and the value of d2 ranges from 3mm to 20mm. For example, the distance d1 between the narrowed portion 120 and the opening 110 can be 2mm, 10mm, 15mm, etc., and the length d2 of the narrowed portion 120 can be 3mm, 8mm, 15mm, etc. Within these ranges, d1 and d2 can meet the sealing requirements. It is understandable that when the distance between the narrowed portion 120 and the opening 110 is less than 2mm, the narrowed portion 120 is too close to the opening 110, increasing the difficulty of processing the narrowed portion 120 and potentially affecting the structural strength. When the length of the narrowed portion 120 is less than 3mm, the length of the sealing layer 310 will also decrease, reducing the quality of the sealing layer 310. When the length of the narrow section 120 is greater than 20mm, it will result in excessive use of sealing material 300, which is not conducive to reducing costs. The specific length of the narrow section 120 can be selected according to the actual application requirements.

[0067] The encapsulation method of the getter of the present invention will be described below with specific examples, and comparative examples will be provided for comparison.

[0068] Example 1: The metal tube 100 used is made of 6063 aluminum alloy. The metal tube 100 has a single-end opening 110, an outer diameter of 10 mm, a length of 90 mm, and a wall thickness of 0.2 mm. The narrowing section 120 is machined 10 mm from the opening 110, and its length is 10 mm. The sealing material 300 is fine glass frit primarily composed of bismuth oxide, with a melting temperature of 360°C. The sealing material 300 is irregularly shaped granules, with an average diameter larger than the narrow space formed by the uneven structure 140. The gas-absorbing material 200 is a silicon-based molecular sieve with a stability temperature of 650°C.

[0069] Reference Figure 9 As shown, the encapsulation method steps in Embodiment 1 include: Step S510: The sealing material is pretreated at 550°C for 2 hours to remove internal gas; In step S520, the suction material 200 is placed at the bottom of the metal tube 100, and a narrowing portion 120 is formed on the metal tube 100. The narrowing portion 120 has a concave-convex structure 140, and a sealing material 300 is added to the narrowing portion 120 in an amount of 0.25g. In step S530, the metal tube 100 containing the gas-absorbing material 200 and the sealing material 300 is placed in a vacuum environment with a preset vacuum degree of 0.0015 Pa. After reaching the preset vacuum degree, the metal tube 100 is heated to 250°C and maintained for 3 hours to allow the gas-absorbing material 200 to fully release the internal gas under low pressure and high temperature. Step S540: Raise the temperature to 500°C and maintain it for 4 hours to melt the sealing material 300 to form a sealing layer 310, and the sealing layer 310 fills the slit space. Step S550: While maintaining low pressure, reduce the overall temperature to near the room temperature to allow the sealing layer 310 to fully solidify. Step S560: Increase the pressure in the vacuum chamber to atmospheric pressure and remove the prepared getter.

[0070] Example 2: The metal tube 100 used is made of T2 copper. The metal tube 100 has a single-end opening 110, an outer diameter of 10 mm, a length of 90 mm, and a wall thickness of 0.2 mm. The narrowed portion 120 is machined 10 mm from the opening 110, and its length is 10 mm. The sealing material 300 is fine glass frit primarily composed of bismuth oxide, with a melting temperature of 360°C. The sealing material 300 is irregularly shaped granules, with an average diameter larger than the narrow space formed by the uneven structure 140. The gas-absorbing material 200 is a silicon-based molecular sieve with a stable temperature of 650°C.

[0071] The packaging method steps in Example 2 include: Step S610: The sealing material is pretreated at 550°C for 2 hours to remove internal gas; In step S620, the suction material 200 is placed at the bottom of the metal tube 100, and a narrowing portion 120 is formed on the metal tube 100. The narrowing portion 120 has a concave-convex structure 140, and a sealing material 300 is added to the narrowing portion 120 in an amount of 0.25g. In step S630, the metal tube 100 containing the gas-absorbing material 200 and the sealing material 300 is placed in a vacuum environment with a preset vacuum degree of 0.0015 Pa. After reaching the preset vacuum degree, the metal tube 100 is heated to 250°C and maintained for 3 hours to allow the gas-absorbing material 200 to fully release the internal gas under low pressure and high temperature. Step S640: Raise the temperature to 500°C and maintain it for 4 hours to melt the sealing material 300 to form a sealing layer 310, and the sealing layer 310 fills the slit space. Step S650: While maintaining low pressure, reduce the overall temperature to near the room temperature to allow the sealing layer 310 to fully solidify. Step S660: Increase the pressure in the vacuum chamber to atmospheric pressure and remove the prepared getter.

[0072] Comparative Example 1: The metal tube 100 used is made of 6063 aluminum alloy. The metal tube 100 has a single-end opening 110, an outer diameter of 10 mm, a length of 90 mm, and a wall thickness of 0.2 mm. The narrow section 120 is machined 10 mm from the opening 110, and its length is 10 mm. The narrow section 120 has no uneven structure 140, meaning its inner wall is smooth. The sealing material 300 is fine glass frit primarily composed of bismuth oxide, with a melting temperature of 360℃. The gas-absorbing material 200 is a silicon-based molecular sieve with a stable temperature of 650℃.

[0073] The encapsulation method steps in Comparative Example 1 include: Step S511: The sealing material is pretreated at 550°C for 2 hours to remove internal gas; Step S521: Place the suction material 200 at the bottom of the metal tube 100, process a narrowing part 120 on the metal tube 100, and add sealing material 300 in the narrowing part 120, with an amount of 0.5g. Step S531: Place the metal tube 100 containing the gas-absorbing material 200 and the sealing material 300 in a vacuum environment with a preset vacuum degree of 0.0015 Pa; after reaching the preset vacuum degree, heat the metal tube 100 to raise the temperature to 250°C and maintain it for 3 hours to allow the gas-absorbing material 200 to fully release the internal gas under low pressure and high temperature. Step S541: Raise the temperature to 500°C and maintain it for 4 hours to melt the sealing material 300 to form a sealing layer 310, and the sealing layer 310 fills the narrowed portion 120. Step S551: While maintaining low pressure, reduce the overall temperature to near the room temperature to allow the sealing layer 310 to fully solidify. Step S561: Increase the pressure in the vacuum chamber to atmospheric pressure and remove the prepared getter.

[0074] Comparative Example 2: The metal tube 100 used is made of 6063 aluminum alloy. The metal tube 100 has a single-end opening 110, an outer diameter of 10 mm, a length of 90 mm, and a wall thickness of 0.2 mm. The constricted section 120 is machined 10 mm from the opening 110, and its length is 10 mm. The sealing material 300 is irregular virgin bismuth oxide glass frit, i.e., untreated sealing material, with a melting temperature of 360℃. The gas-absorbing material 200 is a silicon-based molecular sieve with a stabilization temperature of 650℃.

[0075] The encapsulation method steps in Comparative Example 2 include: Step S621: Place the suction material 200 at the bottom of the metal tube 100, and process a narrowing portion 120 on the metal tube 100. The narrowing portion 120 has a concave-convex structure 140. Add sealing material to the narrowing portion 120 in an amount of 0.25g. Step S631: Place the metal tube 100 containing the gas-absorbing material 200 and the sealing material in a vacuum environment with a preset vacuum degree of 0.0015 Pa; after reaching the preset vacuum degree, heat the metal tube 100 to raise the temperature to 250°C and maintain it for 3 hours to allow the gas-absorbing material 200 to fully release the internal gas under low pressure and high temperature. Step S641: Raise the temperature to 650°C and maintain it for 4 hours to melt the sealing material 300 to form a sealing layer 310, and the sealing layer 310 fills the slit space. Step S651: While maintaining low pressure, reduce the overall temperature to near the room temperature to allow the sealing layer 310 to fully solidify. Step S661: Increase the pressure in the vacuum chamber to atmospheric pressure and remove the prepared getter.

[0076] The above tests and comparisons demonstrate that adding a concave-convex structure 140 to the narrowed section 120, and using 0.25g of pre-treated sealing material 300 (Examples 1 and 2), can achieve a good seal. The prepared getter was placed in a sealed environment with a pressure of 10 Pa and a volume of 0.002 m³. The flexible outer shell was then mechanically broken to connect the receiving cavity 150 with the area requiring increased vacuum. After 24 hours, the pressure of the sealed environment decreased to approximately 0.6 Pa.

[0077] In Comparative Example 1, the sealing material 300 is an irregular granular metal oxide. In order to ensure that the sealing material 300 flows and fills the narrowed part 120 with a smooth inner wall, the amount of sealing material 300 used is 0.5 g, which means that a larger amount of sealing material 300 (Comparative Example 1) is needed to achieve a good seal. In Comparative Example 2, the sealing material can only be fully melted at about 650°C under vacuum. That is, the untreated sealing material 300 (Comparative Example 2) requires a higher sealing temperature to achieve a good seal.

[0078] Therefore, the packaging method of this embodiment of the invention forms a narrowed portion 120 at the location requiring packaging, reducing the gap space that needs to be sealed. Furthermore, a concave-convex structure 140 is formed inside the narrowed portion 120 to clamp and fix the small sealing material 300. By using the structure of the narrowed portion 120, the concave-convex structure 140 is added within a smaller gap space, further reducing the size of the gap space. A small amount of sealing material 300 is sufficient to seal the gap space within the narrowed portion 120, effectively reducing the amount of sealing material 300 used. With the reduced amount of sealing material 300, the heating time required during processing is also reduced, which helps to reduce energy consumption. Moreover, with a smaller gap space, the reliability of the sealing layer 310 is higher, the sealing effect is better, the processing yield is improved, and the processing cost is reduced.

[0079] This invention also provides a getter, which is processed using the encapsulation method described above. Since the getter can reduce the required sealing gap space and can clamp the small sealing material 300 inside the narrowed portion 120 through the concave-convex structure 140, the amount of sealing material 300 used can be reduced, the temperature required for the processing can be reduced, and the processing yield can be improved, which is beneficial to reducing the cost of the getter.

[0080] It should be noted that the getter is not limited to being processed using the encapsulation method of the above embodiments, and other encapsulation methods can also be used to prepare the getter of the present invention.

[0081] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for encapsulating a getter, characterized in that, include: An air-absorbing material is placed inside a metal tube, wherein at least one end of the metal tube has an opening; The end of the metal tube with the opening is processed to form a narrow section. The inner diameter of the narrow section is smaller than the inner diameter of the metal tube, and the inner wall of the narrow section has a concave-convex structure. A sealing material is placed in the narrow section and fixed in the concave-convex structure. The metal tube containing the air-absorbing material and the sealing material is placed in a vacuum environment; In the vacuum environment, the metal tube is heated, and the heating temperature is controlled to reach a first preset temperature and maintained for a first preset time, so that the sealing material melts and fills the narrowed part to form a sealing layer. The first preset temperature is greater than the melting temperature of the sealing material and less than the melting temperature of the air-absorbing material.

2. The encapsulation method for the getter according to claim 1, characterized in that, In the vacuum environment, before heating the metal tube and controlling the heating temperature to reach a first preset temperature and maintain it for a first preset time, the encapsulation method further includes: The metal pipe is heated, and the heating temperature is controlled to reach a second preset temperature and maintained for a second preset time, so that the gas inside the gas-absorbing material can be released in a vacuum environment. The second preset temperature is lower than the melting temperature of the sealing material.

3. The encapsulation method for the getter according to claim 1, characterized in that, The process of forming a narrowed portion at the end of the metal tube with the opening includes: The metal tube is squeezed near the opening to narrow the tube body and form the narrowed portion. The concave-convex structure is integrally formed with the narrowed portion, or the concave-convex structure is formed on the inner wall of the narrowed portion after the narrowed portion is formed.

4. The encapsulation method for the getter according to claim 3, characterized in that, The extrusion of the metal tube near the opening includes: The outer wall of the metal tube is extruded along the radial direction of the metal tube, causing the outer wall of the metal tube to be concave to form an annular groove. The concave-convex structure is formed on the inner wall of the narrowed portion and is arranged away from the bottom wall of the annular groove. The annular groove has two opposite side walls that are inclined toward the axis of the metal tube, so that the annular groove gradually narrows from the outside to the inside; the inner wall of the metal tube has a first end face and a second end face, and the narrowing part is located between the first end face and the second end face.

5. The encapsulation method for the getter according to claim 4, characterized in that, The encapsulation method further includes: Before the air-absorbing material is placed inside the metal pipe, the metal pipe is processed so that one end of the metal pipe has the opening and the other end forms a closed bottom. After the narrowed portion is formed by processing the end of the metal tube with the opening, the first end face faces the bottom of the metal tube, so that a receiving cavity is formed between the first end face and the bottom of the metal tube, and the first end face can prevent the air-absorbing material from entering the narrowed portion.

6. The encapsulation method for the getter according to claim 5, characterized in that, The step of placing air-absorbing material inside the metal tube includes: the amount of air-absorbing material is sufficient to fill the receiving cavity after the narrowing section is formed.

7. The encapsulation method of the getter according to any one of claims 1 to 6, characterized in that, The outer diameter of the metal pipe is greater than or equal to 3 mm, the wall thickness of the metal pipe is less than or equal to 1 mm, and the length of the metal pipe is greater than the outer diameter of the metal pipe. And / or, the distance between the narrowed portion and the opening ranges from 2mm to 20mm, and the length of the narrowed portion ranges from 3mm to 20mm.

8. The method for encapsulating a getter according to any one of claims 1 to 6, characterized in that, The sealing material has a granular or sheet-like glassy structure, and the average length dimension of the sealing material is greater than the maximum inner diameter enclosed by the concave and convex structure. And / or, the melting temperature range of the sealing material is 300°C to 500°C; And / or, the air-absorbing material is a powder or granular material with air-absorbing capacity; And / or, the metal tubing is made of any one of iron, aluminum, or copper, or an alloy of iron, aluminum, or copper.

9. The encapsulation method for the getter according to claim 1, characterized in that, The encapsulation method further includes: The sealing material is pretreated at a third preset temperature and maintained for a third preset time to form the sealing material. The third preset temperature is greater than the melting temperature of the sealing material and the difference ranges from 50°C to 200°C.

10. The encapsulation method for the getter according to claim 1, characterized in that, After the sealing material is melted and filled into the narrowed portion to form a sealing layer, the encapsulation method further includes: The heating temperature is controlled to be reduced from the first preset temperature to the ambient temperature, causing the sealing layer to solidify; The pressure in the vacuum environment is increased to atmospheric pressure to complete the preparation of the getter.

11. A getter, characterized in that, The getter includes a metal tube with an opening at at least one end. The end of the metal tube with the opening has a narrowing portion with an inner diameter smaller than the inner diameter of the metal tube. The inner wall of the narrowing portion has an uneven structure. The narrowing portion is filled with a sealing layer, which is formed by melting a sealing material placed within the uneven structure.

12. The getter according to claim 11, characterized in that, The outer diameter of the metal pipe is greater than or equal to 3 mm, the wall thickness of the metal pipe is less than or equal to 1 mm, and the length of the metal pipe is greater than the outer diameter of the metal pipe. And / or, the distance between the narrowed portion and the opening ranges from 2mm to 20mm, and the length of the narrowed portion ranges from 3mm to 20mm; And / or, the metal tubing is made of any one of iron, aluminum, or copper, or an alloy of iron, aluminum, or copper.

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