Electron beam evaporation source liner outgassing apparatus and method

Abstract

The application provides an electron beam evaporation source liner degassing device and a degassing method, and belongs to the technical field of ultrahigh vacuum. The electron beam evaporation source liner degassing device comprises an inlet cavity, a buffer cavity and a growth cavity connected in sequence, and further comprises: a sample conveying unit, comprising a trolley sliding rail, an inlet trolley moving along the trolley sliding rail, and a sample conveying unit; a vacuum pumping unit, comprising a molecular pump and a molecular pump gate valve, the molecular pump being communicated with the inlet cavity through the molecular pump gate valve and being used for pumping the inlet cavity to an ultrahigh vacuum state; a pre-baking unit, comprising an internal baking lamp arranged in the inlet cavity and being used for pre-baking treatment of the liner; a heating unit, comprising a heating table arranged in the inlet cavity and being used for heating degassing treatment of the liner; and a bearing assembly, comprising an isolation support for bearing the liner and a supporting support for supporting the isolation support, the bearing assembly being capable of being placed on the inlet trolley and being capable of being conveyed to the heating table through the sample conveying unit.

Description

Technical Field

[0001] This application belongs to the field of ultra-high vacuum technology, specifically relating to an electron beam evaporation source bushing degassing device and degassing method. Background Technology

[0002] Before use, an electron beam evaporation source typically requires a bushing between the source material and the copper crucible. This bushing not only protects the copper crucible from direct electron beam bombardment and prevents cross-contamination between different source materials, but also reduces heat loss from the source material and improves evaporation efficiency. Depending on the evaporation material, the bushing can be made of various materials such as graphite, alumina, copper, molybdenum, tantalum, and tungsten. However, if the bushing itself contains many impurities, it will contaminate the source material during evaporation, thus affecting the purity of the deposited film. Therefore, heating and degassing the bushing before loading is of significant practical importance.

[0003] Currently, there are two main methods for degassing bushings.

[0004] The first method involves directly using an electron beam evaporation source to heat and degas the bushing with low current. This method is suitable for bushings made of high-melting-point metals such as molybdenum, tantalum, and tungsten. However, after degassing, the cavity needs to be broken to allow for loading, resulting in high time and maintenance costs. Furthermore, improper control of the heating current may cause the bushing to melt. In addition, this method is not suitable for non-metallic bushings such as graphite, because direct electron beam bombardment of graphite will produce carbon contamination, severely affecting the film quality.

[0005] The second method is to build a dedicated independent chamber for degassing. This chamber needs to be equipped with a dry pump, molecular pump, heating platform, temperature control system, and water cooling system, etc. It occupies a large area, is complex to operate, is expensive, and has a long baking and maintenance cycle.

[0006] It is evident that existing bushing degassing technologies suffer from problems such as inconvenient operation, high cost, limited applicability, or susceptibility to secondary pollution. There is an urgent need for a more economical, efficient, and versatile bushing degassing method and device. Summary of the Invention

[0007] To address the aforementioned technical problems, this application provides an electron beam evaporation source bushing degassing device and degassing method, aiming to at least partially solve the above-mentioned technical problems. The specific technical solution provided by this application is as follows.

[0008] As a first aspect of this application, an electron beam evaporation source bushing degassing device is provided, comprising a sample inlet chamber, a buffer chamber, and a growth chamber connected in sequence. The sample inlet chamber and the buffer chamber are connected through a buffer chamber gate valve, and the growth chamber and the buffer chamber are connected through a growth chamber gate valve. The sample inlet chamber is connected to the outside through an opening and closing door. The device also includes:

[0009] The sample transfer unit includes a trolley slide rail disposed in the sample injection chamber and the buffer chamber, a sample injection trolley that moves along the trolley slide rail, and a sample transfer unit.

[0010] The vacuum pumping unit includes a molecular pump and a molecular pump gate valve. The molecular pump is connected to the injection chamber through the molecular pump gate valve and is used to evacuate the injection chamber to an ultra-high vacuum state.

[0011] The pre-baking unit includes a built-in baking lamp tube disposed in the sample injection chamber for pre-baking the bushing;

[0012] The heating unit includes a heating stage disposed within the injection chamber for heating and degassing the bushing; and

[0013] The carrier assembly includes an isolation holder for carrying the bushing and a support holder for supporting the isolation holder. The carrier assembly can be placed on the sample loading trolley and can be transferred to the heating stage via the sample transfer unit.

[0014] As a second aspect of this application, a method for degassing an electron beam evaporation source bushing is provided, applicable to the aforementioned electron beam evaporation source bushing degassing apparatus, comprising the following steps:

[0015] The liner to be degassed is placed in the carrier assembly, and the carrier assembly is placed on the injection trolley and sent into the injection chamber. The carrier assembly includes an isolation support for carrying the liner and a support support for supporting the isolation support.

[0016] Evacuate the sample injection chamber to an ultra-high vacuum state;

[0017] The built-in baking lamp in the injection chamber is used to pre-bake the bushing inside the carrier assembly;

[0018] The pre-baked carrier assembly is transferred to the heating stage in the injection chamber, and the bushing inside the carrier assembly is heated and degassed.

[0019] In this embodiment, based on the electron beam evaporation source bushing degassing device and method provided in this application, the bushing is placed in a support assembly consisting of an isolation holder and a support holder, and flexibly transported using a trolley slide rail, a sample carriage, and a sample transfer unit within the sample injection chamber. Combined with the vacuum pumping unit, built-in baking lamp, and heating stage integrated into the sample injection chamber, pre-baking and heating degassing processes under ultra-high vacuum are completed sequentially. This application fully utilizes the existing sample injection chamber and vacuum system in the electron beam evaporation device, eliminating the need for an additional independent degassing chamber, thus significantly reducing equipment costs and floor space. Simultaneously, it avoids the problems of repeated vacuum breaking, cross-contamination, and material damage caused by direct heating degassing within the growth chamber, simplifying the operation process, shortening the maintenance cycle, improving bushing degassing efficiency, and being compatible with bushings of various materials, providing a reliable guarantee for the stable preparation of high-purity thin films. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the electron beam evaporation source bushing degassing device in the embodiments of this application;

[0021] Figure 2 This is an exploded structural diagram of the source material, bushing, and load-bearing components in the embodiments of this application;

[0022] Figure 3 This is a schematic diagram of the stacked state of the bushing and the supporting component in an embodiment of this application;

[0023] Figure 4 This is a structural diagram showing the source material, bushing, and load-bearing components stacked sequentially in an embodiment of this application.

[0024] Figure 5 This is a schematic diagram of the structure of the sample introduction cart carrying the support components in an embodiment of this application;

[0025] Figure 6 This is a schematic cross-sectional view of the isolation tray in an embodiment of this application;

[0026] Figure 7 This is a flowchart of the electron beam evaporation source bushing degassing method in the embodiments of this application;

[0027] Explanation of reference numerals in the attached figures:

[0028] 1-Sample inlet chamber; 2-Buffer chamber; 3-Open / close door; 4-Buffer chamber gate valve; 5-Trolley slide rail; 6-Sample inlet trolley; 7-Sample transfer handle; 8-Rotating transfer cup; 9-Molecular pump; 10-Molecular pump gate valve; 11-Built-in baking lamp; 12-Heating stage; 13-Source material; 14-Bushing; 15-Isolation holder; 16-Support holder. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0030] In realizing the concept of this application, it was discovered that decoupling the functions of the growth chamber and the sample inlet chamber in an electron beam evaporation apparatus, and using the original sample inlet chamber as the liner degassing site, can fundamentally avoid the problems of repeated vacuum breaking and cross-contamination in the growth chamber. However, existing sample inlets lack a suitable support and transport structure for liner heating and degassing, and cannot achieve batch degassing of multiple liners without introducing additional contamination. Based on this, this application provides an electron beam evaporation source liner degassing device and method. By setting up a sample transport unit, a vacuum pumping unit, a pre-baking unit, a heating unit, and a support assembly composed of an isolation holder and a support holder, ultra-high vacuum is obtained using the vacuum pumping unit built into the sample inlet chamber, and the liners are pre-baked and heated for degassing in sequence. This achieves economical, efficient, and clean pretreatment of liners made of common materials, significantly reducing maintenance costs, shortening maintenance cycles, and improving film purity.

[0031] Figure 1 This is a schematic diagram of the overall structure of the electron beam evaporation source bushing degassing device in the embodiments of this application; Figure 2 This is an exploded structural diagram of the source material, bushing, and load-bearing components in the embodiments of this application; Figure 3 This is a schematic diagram of the stacked state of the bushing and the supporting component in an embodiment of this application; Figure 4 This is a structural diagram showing the source material, bushing, and load-bearing components stacked sequentially in an embodiment of this application. Figure 5 This is a schematic diagram of the structure of the sample injection cart carrying the supporting components in an embodiment of this application.

[0032] As a first aspect of this application, an electron beam evaporation source bushing degassing device is provided, such as Figures 1-5 As shown, the system includes a sample injection chamber 1, a buffer chamber 2, and a growth chamber (not shown) connected in sequence. The sample injection chamber 1 and the buffer chamber 2 are connected by a buffer chamber gate valve 4, and the growth chamber and the buffer chamber 2 are connected by a growth chamber gate valve (not shown). The sample injection chamber 1 is connected to the outside world through a switch door 3. The system also includes:

[0033] The sample transfer unit includes a trolley slide rail 5 disposed in the sample injection chamber 1 and the buffer chamber 2, a sample injection trolley 6 that moves along the trolley slide rail 5, and a sample transfer unit.

[0034] The vacuum pumping unit includes a molecular pump 9 and a molecular pump gate valve 10. The molecular pump 9 is connected to the sample injection chamber 1 through the molecular pump gate valve 10 and is used to evacuate the sample injection chamber 1 to an ultra-high vacuum state.

[0035] The pre-baking unit includes a built-in baking lamp 11 disposed in the sample injection chamber for pre-baking the bushing 14;

[0036] The heating unit includes a heating stage 12 disposed within the injection chamber for heating and degassing the bushing 14; and

[0037] The carrier assembly includes an isolation tray 15 for carrying the bushing 14 and a support tray 16 for supporting the isolation tray 15. The carrier assembly can be placed on the sample carriage 6 and can be transferred to the heating stage 12 via the sample transfer unit.

[0038] In this embodiment, based on the electron beam evaporation source bushing degassing device provided in this application, a sample transfer unit is set up to enable flexible movement of the bushing 14 between the sample inlet chamber 1 and the buffer chamber 2. A vacuum pumping unit is used to evacuate the sample inlet chamber 1 to an ultra-high vacuum, and the pre-baking and heating degassing processes are completed sequentially with the help of the built-in baking lamp tube 11 and the heating stage 12. Among them, the bearing component uses an isolation bracket 15 to directly support the bushing 14, and is supported and fixed by a support bracket 16. The isolation bracket 15 can effectively isolate the bushing 14 and the support bracket 16 to avoid cross-contamination of materials, and can also prevent the metal bushing 14 from sticking to the support bracket 16 after heating degassing. The electron beam evaporation source bushing device provided in this application makes full use of the original sample inlet chamber 1 and vacuum system of the electron beam evaporation device, eliminating the need to build a separate dedicated degassing chamber, which significantly reduces equipment costs and floor space. At the same time, by transferring the degassing process to the sample inlet chamber 1, the repeated vacuum breaking and cross-contamination of the growth chamber are avoided, simplifying the operation process, shortening the maintenance cycle, improving the bushing degassing efficiency, and being compatible with bushings of various materials, providing a reliable guarantee for the stable preparation of high-purity thin films.

[0039] In some embodiments, such as Figure 2 As shown, the isolation holder 15 is a cylindrical structure with an opening at one end, and the opening end of the cylindrical structure extends radially outward to form a raised edge.

[0040] In this embodiment, the isolation holder 15 adopts a cylindrical structure with one open end, and a raised edge extends radially outward from the open end. This structure provides a stable, circumferentially closed receiving space for the bushing 14, preventing the bushing 14 from tilting or slipping during transfer and heating. Simultaneously, the raised edge facilitates engagement with the support holder 16 for positioning, making the transfer of the isolation holder 15 between the sample loading carriage 6 and the heating stage 12 more reliable and its positioning more accurate, thereby improving the safety and consistency of the bushing degassing operation.

[0041] In some embodiments, the support holder 16 is an annular structure. The inner edge of the annular structure is provided with a recess for accommodating and limiting the isolation holder 15. The outer edge of the annular structure is provided with a plurality of protrusions at intervals. The protrusions are used to cooperate with and fix the sample loading carriage 6 and the heating stage 12.

[0042] In this embodiment, the annular structure of the support tray 16 has a recessed platform along its inner edge. This platform can accommodate the isolation tray 15 and limit its movement. Specifically, it cooperates with the protruding edge at the opening end of the isolation tray 15. The radial displacement of the isolation tray 15 is constrained by the sidewall of the recessed platform, and its axial sinking is limited by the bottom surface of the recessed platform supporting the protruding edge. This achieves precise positioning and stable placement of the isolation tray 15 on the support tray 16. At the same time, multiple protrusions on the outer edge cooperate and are fixed with the sample carriage 6 and the heating stage 12 to ensure the overall stability of the load-bearing components during the transfer and heating process. This structure can achieve reliable limiting without additional fasteners, simplifying operation, avoiding bushing damage caused by shaking, tipping, or uneven thermal expansion, and improving the safety and consistency of the degassing process.

[0043] In some embodiments, the isolation bracket 15 is made of pyrolytic boron nitride; the support bracket 16 is made of tantalum. Furthermore, both the pyrolytic boron nitride and the tantalum are 99.99% pure and can withstand high-temperature environments exceeding 1000°C.

[0044] In this embodiment, pyrolytic boron nitride possesses extremely high chemical inertness and good thermal conductivity. As an isolation bracket 15, it effectively blocks material diffusion between the bushing 14 and the support bracket 16, preventing the migration and contamination of the bushing 14 by metallic impurities at high temperatures. Simultaneously, its high purity ensures that no new contaminants are introduced during the degassing process. Tantalum metal possesses excellent high-temperature strength and creep resistance. As a support bracket 16, it maintains structural stability during repeated high-temperature cycles and is not prone to adhesion to the isolation bracket 15. The combination of these two materials ensures the reliability and durability of the load-bearing components under ultra-high vacuum heating and degassing conditions, while fundamentally eliminating cross-contamination caused by material volatilization or reaction, thereby guaranteeing the purity of the bushing degassing.

[0045] In some embodiments, the sample transfer unit includes a sample transfer handle 7 and a rotating sample transfer cup 8. The sample transfer handle 7 is used to vertically lift the carrier component, and the rotating sample transfer cup 8 is used to transfer the carrier component to the heating stage 12 in the horizontal direction.

[0046] In this embodiment, the sample transfer unit uses a combination of a sample transfer handle 7 and a rotating sample transfer cup 8. The sample transfer handle 7 is used to vertically lift the carrier component, and the rotating sample transfer cup 8 is used to horizontally transfer the carrier component to the heating stage 12. This achieves non-contact, bidirectional, and flexible transfer of the carrier component between the sample loading carriage 6 and the heating stage 12, avoiding contamination or positional deviations that may be introduced by direct manual operation. At the same time, by decoupling the vertical and horizontal movements, the positioning accuracy and operational stability during the transfer process are significantly improved, ensuring that the carrier component can smoothly and accurately reach the pre-baking and degassing station, thereby improving the automation and repeatability of the bushing degassing process.

[0047] Figure 6 This is a cross-sectional schematic diagram of the isolation tray in an embodiment of this application.

[0048] In some embodiments, such as Figure 6 As shown, the isolation tray 15 adopts a lightweight design. For example, its wall thickness can be set to 1mm-2mm to maximize the internal capacity while ensuring strength. Considering the bottom space of the sample carriage 6, the internal dimensions of the heating stage 12, and the operating height of the sample transfer handle 7, the inner depth of the isolation tray 15 can be designed to be 13mm-14mm. Taking a bushing that fits a 15cc crucible as an example, the bushing is approximately 17mm high, and after being placed in the isolation tray 15, about 3mm-4mm protrudes from the surface, thus avoiding contact with the interior of the heating stage 12 and affecting normal heating. The inner diameter of the isolation tray 15 can be set to 39mm-40mm to accommodate a 15cc bushing with a maximum outer diameter of 37.7mm, and it can also be used for other bushings of 15cc size and below. The maximum outer diameter of the isolation tray 15 can be set to 52.6mm-53mm, with an expansion gap of about 0.8mm-1mm reserved between its edge and the support tray 16 to prevent crushing or jamming caused by high-temperature thermal expansion.

[0049] In some embodiments, the thickness of the support holder 16 can be, for example, 2mm-2.5mm, and the outer diameter can be 86mm. Three protrusions are spaced apart along the outer edge of the support holder 16, each protrusion having a depth of 4.4mm-4.6mm, for fixed engagement with the sample carriage 6 and the heating stage 12. The minimum inner diameter of the inner ring of the support holder 16 can be set to 45.8mm-46mm, with sufficient expansion clearance reserved between it and the isolation holder 15 to ensure dimensional compatibility at high temperatures.

[0050] In some embodiments, the electron beam evaporation source bushing degassing device further includes the following components: a heating power supply and temperature controller, electrically connected to the heating stage 12, for precisely controlling the heating rate and degassing temperature of the heating stage 12; an ion gauge and a coarse gauge, respectively disposed on the sample injection chamber 1, wherein the coarse gauge is used to monitor the vacuum level in the low vacuum stage, and the ion gauge is used to measure the vacuum level in the high vacuum and ultra-high vacuum stages, and the two together provide feedback on the vacuum state in the sample injection chamber 1; and a dry pump, connected in series with the molecular pump 9, serving as a backing pump to provide the required pre-vacuum for the molecular pump 9. Through the coordinated operation of these components, real-time monitoring and precise control of the vacuum level and heating temperature of the sample injection chamber 1 can be achieved, thereby ensuring the stability and repeatability of the bushing degassing process.

[0051] Figure 7 This is a flowchart of the electron beam evaporation source bushing degassing method in the embodiments of this application.

[0052] As a second aspect of this application, a method for degassing an electron beam evaporation source bushing is provided, applicable to the aforementioned electron beam evaporation source bushing degassing device, such as... Figure 7As shown, it includes steps S1-S4.

[0053] Step S1: Place the degassing bushing 14 into the carrier assembly, and place the carrier assembly on the sample injection trolley 6 and send it into the sample injection chamber 1. The carrier assembly includes an isolation support 15 for carrying the bushing 14 and a support support 16 for supporting the isolation support 15.

[0054] Step S2: Evacuate the sample injection chamber 1 to an ultra-high vacuum state.

[0055] Step S3: Use the built-in baking lamp 11 in the sample injection chamber 1 to pre-bake the bushing 14 in the carrier assembly.

[0056] Step S4: Transfer the pre-baked carrier assembly to the heating stage 12 in the sample injection chamber 1, and heat and degas the bushing 14 inside the carrier assembly.

[0057] In this embodiment, based on the electron beam evaporation source bushing degassing method provided in this application, the bushing 14 is placed in a support assembly consisting of an isolation holder 15 and a support holder 16 and then fed into the sample inlet chamber 1. Ultra-high vacuum is obtained using the vacuum pumping unit built into the sample inlet chamber 1, followed by pre-baking and heating degassing treatments. This method fully utilizes the existing sample inlet chamber and vacuum system of the electron beam evaporation device, eliminating the need for a separate degassing chamber, significantly reducing equipment costs and floor space. Simultaneously, transferring the degassing process to the sample inlet chamber avoids the repeated vacuum breaking, cross-contamination, and material damage problems caused by direct heating degassing in the growth chamber. This simplifies the operation process, shortens the maintenance cycle, improves bushing degassing efficiency, and is compatible with bushings of various materials, providing a reliable guarantee for the stable preparation of high-purity thin films.

[0058] In some embodiments, the pre-baking temperature of the pre-baking treatment is 180-220°C, for example, 180°C, 200°C, or 220°C, preferably 200°C; the pre-baking time is 5-10 hours, for example, 5 hours, 8 hours, or 10 hours, preferably 8-10 hours.

[0059] In the embodiments of this application, by setting appropriate pre-baking temperatures and times, low-boiling-point impurities such as water vapor adsorbed on the bushing surface and cavity walls can be effectively removed. While avoiding adverse changes in the bushing material, the background vacuum of the injection cavity is significantly improved, creating a clean and stable ultra-high vacuum environment for subsequent high-temperature degassing, thereby ensuring the reliability and consistency of the overall degassing process.

[0060] In some embodiments, the degassing temperature of the heating degassing treatment is 600-1000℃, for example, 600℃, 700℃, 800℃, 900℃, 1000℃, preferably 800-900℃; the degassing time is 5-10h, for example, 5h, 6h, 7h, 8h, 9h, 10h, preferably 6-8h.

[0061] In this embodiment, by controlling the temperature and time of the heating degassing process within a suitable range, various impurity gases adsorbed inside and on the surface of the bushing can be effectively removed, significantly improving the cleanliness of the bushing and thus effectively preventing contamination of the source material during subsequent loading and growth. At the same time, the process conditions take into account both the degassing effect and the thermal stability of the bushing material, avoiding bushing deformation, melting, or material performance degradation caused by excessively high temperature or time, ensuring the safety and reliability of the degassing process, and providing a strong guarantee for the stable preparation of high-purity films.

[0062] In some embodiments, the vacuum level in the ultra-high vacuum state is 5 × 10⁻⁶. -9 Torr~1×10 -7 Torr, preferably 5×10 -9 Torr~1×10 -8 Torr.

[0063] Furthermore, to achieve this vacuum condition, a molecular pump 9 with a nitrogen pumping speed of 260L / s-685L / s can be equipped. This molecular pump 9 can provide the required background vacuum environment for liner degassing, thereby effectively reducing residual impurity gases in the environment and improving the liner degassing effect.

[0064] In some embodiments, the heating and degassing process employs a stepped heating method: first, the temperature is raised to 600°C at a rate of 10°C / min to 30°C / min and held for 30 minutes. After the vacuum stabilizes, the temperature is then raised to the target degassing temperature at a rate of 10°C / min to 15°C / min.

[0065] In this embodiment, the heating and degassing process employs a stepped heating method. First, a lower temperature range is maintained to allow the volatile impurities adsorbed on and inside the bushing to be fully released under stable vacuum conditions. Once the vacuum stabilizes, the temperature is then increased to the target degassing temperature. This method effectively avoids sudden large-scale gas release caused by excessively rapid heating, prevents drastic fluctuations in vacuum, and prevents secondary adsorption of impurities onto the bushing. This ensures the stability, controllability, and cleanliness of the degassing process, improving the consistency and reliability of bushing degassing.

[0066] In some embodiments, the electron beam evaporation source bushing degassing method is applicable to bushings 14 with a volume of 15cc or less, and the bushing material is selected from any one of graphite, alumina, pyrolytic boron nitride, boron nitride, copper, molybdenum, tantalum, tungsten, and niobium.

[0067] In the embodiments of this application, the electron beam evaporation source bushing degassing method provided is applicable to bushings of various materials and small volumes. It can effectively degas common bushing materials such as graphite, alumina, pyrolytic boron nitride, copper, molybdenum, tantalum, tungsten, and niobium, while also being compatible with different sizes. This broad applicability enables clean pretreatment of bushings in various electron beam evaporation process scenarios, significantly improving the versatility and flexibility of the degassing device and reducing the cost for users to replace degassing equipment or processes for different bushings.

[0068] In some embodiments, the electron beam evaporation source bushing degassing method can pre-bake multiple bushings simultaneously and then heat-degass each bushing sequentially. During the heating and degassing process, the sample carriage 6 is used to send the remaining bushing-bearing components into the buffer chamber 2 to avoid contamination.

[0069] In this embodiment, the electron beam evaporation source bushing degassing method provided can simultaneously pre-bake multiple bushings (e.g., 1-5), and sequentially perform heating degassing on each bushing. During the heating degassing process, the sample carriage 6 is used to transport the remaining bushing-carrying components into the buffer chamber 2, thereby effectively preventing cross-contamination of other untreated bushings by released impurity gases. This method achieves batch processing while ensuring the degassing quality of individual bushings, significantly improving bushing pretreatment efficiency, shortening the overall maintenance cycle, and ensuring the consistency of cleanliness for each bushing.

[0070] In some embodiments, the degassing method provided in this application is not only applicable to the bushing 14, but can also be extended to degas the source material 13 of the electron beam evaporation source. Specifically, after the bushing 14 is degassed, the source material 13 can be directly placed into the bushing 14 and subjected to heating degassing treatment following essentially the same steps as bushing degassing. The degassing temperature of the source material 13 can be appropriately selected according to its melting point, and the maximum degassing temperature can reach 1000°C.

[0071] For example, this application provides a specific implementation process of an electron beam evaporation source bushing degassing method, including the following steps.

[0072] (1) The bushing enters the sample inlet cavity.

[0073] First, close the molecular pump gate valve 10 to stop the operation of molecular pump 9 and dry pump. Introduce high-purity nitrogen into the injection chamber 1. Once the pressure inside the chamber exceeds atmospheric pressure, open the switch door 3 and use the trolley rail 5 to push out the injection carriage 6. Place the bushing 14 to be degassed into the support assembly consisting of support bracket 16 and isolation bracket 15, securing the support assembly to the injection carriage 6 using the three protrusions on the support bracket 16. Then, push the injection carriage 6 back into the injection chamber 1, close the switch door 3, open the molecular pump gate valve 10, and sequentially start the dry pump and molecular pump 9 to evacuate the injection chamber 1.

[0074] (2) Pre-baking treatment.

[0075] When the vacuum level in injection chamber 1 is better than 5×10 -9 Torr~1×10 -7 During the Torr process, the built-in baking lamp 11 is turned on to remove moisture adsorbed on the cavity wall, sample carriage 6, carrier assembly, and bushing 14, and to obtain a good background vacuum for the sample injection chamber 1. The sample carriage 6 is moved horizontally along the carriage slide rail 5 to directly below the built-in baking lamp 11 using an external magnet. The baking temperature is set to 200℃, and the baking time is 5-10 hours.

[0076] (3) Heating and degassing treatment.

[0077] After pre-baking, the sample carriage 6 is moved below the sample transfer handle 7. The sample transfer handle 7 has vertical movement and horizontal rotation functions, and is provided with grooves to fix the carrier assembly. First, the carrier assembly is lifted vertically using the sample transfer handle 7; then, the entire carrier assembly is horizontally transferred to the heating stage 12 located in the same sample injection chamber 1 using the rotating sample transfer cup 8, which can rotate at a large angle. The heating stage is also provided with grooves to fix the three protrusions of the support bracket 16. Before heating and degassing, the sample carriage 6 is pushed into the buffer chamber 2 on the right side to prevent the sample carriage 6 and other untreated bushings from being contaminated by impurity gases released at high temperatures.

[0078] The degassing process then begins, with the degassing temperature set at 600-1000℃ and the degassing time at 5-10 hours. If the degassing temperature is too high, a stepped heating method is used: first, the temperature is increased to 600℃ at a rate of 10℃ / min to 30℃ / min, held for 30 minutes, and after the vacuum level stabilizes, the temperature is increased to the target degassing temperature at a rate of 10℃ / min to 15℃ / min. Temperature control uses a PID controller with an accuracy of ±0.1℃.

[0079] (4) Cool down and replace the bushing.

[0080] After heating and degassing, the temperature is reduced at a rate of 20℃ / min to 30℃ / min. The heating stage 12 is equipped with a water cooling system, and the cooling time varies from 10 min to 40 min depending on the degassing temperature. After cooling, the buffer chamber gate valve 4 is opened, and the sample carriage 6 is pushed back from the buffer chamber 2 to the sample carriage 1. Then, the degassed carrier assembly is sequentially transferred from the heating stage 12, the rotating sample transfer cup 8, and the sample transfer handle 7 back to the sample carriage 6. Next, the next bushing to be degassed is replaced, and the above transfer and heating / degassing process is repeated.

[0081] (5) Loading operation after degassing.

[0082] After all the bushings have been degassed, the sample inlet chamber 1 is emptied, all bushings are removed, and they are quickly installed into the growth chamber. Then the source material is loaded, the growth chamber is evacuated, and the entire growth chamber is baked and maintained.

[0083] In summary, this application provides an electron beam evaporation source bushing degassing device and method, which, combined with the original sample inlet chamber of the electron beam evaporation device, utilizes the pump unit integrated into the sample inlet chamber to obtain an ultra-high vacuum environment (up to 5 × 10⁻⁶). -9 This method (Torr) significantly reduces equipment costs. It can perform vacuum degassing on multiple bushings of common materials (applicable to crucible capacities of 15cc and below) within a temperature range of room temperature to 1000°C, effectively releasing impurity gases such as water, oxygen, carbon monoxide, and carbon dioxide, significantly improving bushing cleanliness, reducing bushing contamination of source materials, and ensuring the growth of high-purity films. Simultaneously, this method is simple and convenient to operate, improves bushing compatibility and degassing efficiency, shortens maintenance cycles, and improves the degassing method for electron beam evaporation source bushings. Furthermore, this application is not only applicable to bushing degassing but can also rapidly degas high-melting-point source materials (such as silicon ingots, tantalum ingots, niobium ingots, etc.), further shortening maintenance cycles and demonstrating broad application prospects.

[0084] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An electron beam evaporation source bushing degassing device, comprising a sample inlet chamber, a buffer chamber, and a growth chamber connected in sequence, wherein the sample inlet chamber and the buffer chamber are connected via a buffer chamber gate valve, the growth chamber and the buffer chamber are connected via a growth chamber gate valve, and the sample inlet chamber is connected to the outside via a switch door, characterized in that, Also includes: The sample transfer unit includes a trolley slide rail disposed in the sample injection chamber and the buffer chamber, a sample injection trolley that moves along the trolley slide rail, and a sample transfer unit. The vacuum pumping unit includes a molecular pump and a molecular pump gate valve. The molecular pump is connected to the sample inlet chamber through the molecular pump gate valve and is used to evacuate the sample inlet chamber to an ultra-high vacuum state. The pre-baking unit includes a built-in baking lamp tube disposed in the sample injection chamber for pre-baking the bushing; The heating unit includes a heating stage disposed in the sample injection chamber for heating and degassing the bushing; as well as The carrier assembly includes an isolation holder for carrying the bushing and a support holder for supporting the isolation holder. The carrier assembly can be placed on the sample loading trolley and can be transferred to the heating stage via the sample transfer unit.

2. The electron beam evaporation source bushing degassing device according to claim 1, characterized in that, The isolation holder is a cylindrical structure with an opening at one end, and the opening end of the cylindrical structure extends radially outward to form a raised edge.

3. The electron beam evaporation source bushing degassing device according to claim 1 or 2, characterized in that, The support holder is a ring structure. The inner edge of the ring structure is provided with a recess for accommodating and limiting the isolation holder. The outer edge of the ring structure is provided with a plurality of protrusions at intervals. The protrusions are used to cooperate and fix with the sample loading trolley and the heating stage.

4. The electron beam evaporation source bushing degassing device according to claim 1, characterized in that, The isolation holder is made of pyrolytic boron nitride; The support is made of tantalum.

5. The electron beam evaporation source bushing degassing device according to claim 1, characterized in that, The sample transfer unit includes a sample transfer handle and a rotating sample transfer cup. The sample transfer handle is used to vertically lift the carrier component, and the rotating sample transfer cup is used to transfer the carrier component to the heating table in the horizontal direction.

6. A method for degassing an electron beam evaporation source bushing, applicable to the electron beam evaporation source bushing degassing apparatus according to any one of claims 1-5, characterized in that, Includes the following steps: The liner to be degassed is placed in the carrier assembly, and the carrier assembly is placed on the sample injection trolley and sent into the sample injection chamber. The carrier assembly includes an isolation support for carrying the liner and a support support for supporting the isolation support. The sample inlet chamber is evacuated to an ultra-high vacuum state; The bushing inside the carrier assembly is pre-baked using the built-in baking lamp in the sample injection chamber. The pre-baked carrier assembly is transferred to the heating stage in the sample injection chamber, and the bushing inside the carrier assembly is heated and degassed.

7. The method for degassing the electron beam evaporation source bushing according to claim 6, characterized in that, The pre-baking temperature for the pre-baking process is 180-220℃, and the pre-baking time is 5-10 hours. The degassing temperature of the heating degassing treatment is 600-1000℃, and the degassing time is 5-10h; The vacuum level of the ultra-high vacuum state is 5×10⁻⁶. -9 Torr~1×10 -7 Torr.

8. The method for degassing the electron beam evaporation source bushing according to claim 7, characterized in that, The heating and degassing process adopts a stepped heating method: first, the temperature is raised to 600℃ at a rate of 10℃ / min to 30℃ / min and held for 30 minutes. After the vacuum stabilizes, the temperature is raised to the target degassing temperature at a rate of 10℃ / min to 15℃ / min.

9. The method for degassing the electron beam evaporation source bushing according to claim 6, characterized in that, The electron beam evaporation source bushing degassing method is applicable to bushings with a volume of 15cc or less, wherein the bushing material is selected from any one of graphite, alumina, pyrolytic boron nitride, boron nitride, copper, molybdenum, tantalum, tungsten, and niobium.

10. The method for degassing the electron beam evaporation source bushing according to claim 6, characterized in that, The electron beam evaporation source bushing degassing method can simultaneously pre-baked multiple bushings and sequentially heat-degass each bushing. During the heating degassing process, the sample carriage is used to send the remaining bushing-bearing components into the buffer chamber to avoid contamination.

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