Ultrahigh vacuum electron gun for electron beam evaporation coating

Abstract

The utility model relates to the field, in particular to an ultrahigh vacuum electron gun for electron beam evaporation coating, which comprises an electron gun base, a crucible is mounted at the front end of the electron gun base, an electron emission assembly is loaded in the electron gun base, and each sealing part of the electron emission assembly is sealed by a metal oxygen-free copper ring, so that the leakage rate is greatly reduced, and the electron emission efficiency is improved. The lower end of the crucible is fixedly provided with a water-cooled jacket assembly, and the front end of the water-cooled jacket assembly is fixedly provided with a cooling water pipe joint. When the cooling water pipe connector is used, the cooling water pipe connector in a VCR connection mode is adopted, connection is guaranteed to be more reliable, sealing performance is higher, the whole device structure is more compact, and space is saved.

Description

Technical Field

[0001] The utility model relates to the technical field of electron guns, and particularly relates to an ultra-high vacuum electron gun for electron beam evaporation coating. Background Technique

[0002] The electron beam evaporation coating technology is an advanced physical vapor deposition (PVD) technology. It uses an electron beam evaporation source (electron gun) to heat the material to a molten state and deposit it on the surface of the substrate in a high-vacuum environment to form a thin film. Compared with other PVD thin film deposition processes, electron beam evaporation coating has many advantages, such as: preparation of high-purity and high-precision thin films, ability to evaporate high-melting-point materials, provision of high heat, fast evaporation rate, accurate electron beam positioning to avoid contamination, strong adjustability, wide application range, etc. The electron beam evaporation coating technology is widely used, especially in the preparation of micro-nano processed metal thin films, electronic information, nanoscience, materials science and other fields.

[0003] The most core functional component of the electron beam evaporation coating equipment is the electron gun. The electron gun is a device that generates, accelerates and converges a high-energy density electron beam. It emits an electron beam with a certain energy, a certain beam current, as well as speed and angle to heat and melt the coating material. Specifically, in the electron gun, after the filament (usually a tungsten wire) is energized and heated, a large number of thermoelectrons are generated on the surface. Under the action of the high-voltage electric field between the anode and the cathode, the thermoelectrons accelerate and move at high speed towards the anode direction and obtain a very high kinetic energy. Its specific speed value depends on the level of the acceleration voltage, and generally can reach about two-thirds of the speed of light. Under the action of the focusing coil, the electron beam can be focused, and under the action of the guiding magnetic field (also known as the deflection magnetic field), the electron beam can be deflected to scan the coating material in a certain direction and within a certain range. The working voltage of the electron gun is usually between several thousand volts and several tens of kilovolts. To prevent high-voltage breakdown, beam current scattering and energy loss, the vacuum degree of the electron gun must be maintained above 6.67x10-3 Pa. A large amount of heat will be generated during the heating process by the high-energy electron beam, and the electron gun also needs a water cooling device to protect the crucible and vacuum sealing components.

[0004] Traditional electron guns (such as Figure 1 and 2)It consists of the following parts: 1. The electron emission component 1, which is composed of a helical tungsten cathode, a grid, and an anode, and generates an electron beam; 2. The X coil 3, the Y coil 4, and the scanning coil assembly 10, which change the position of the electron beam in the crucible 5; 3. The permanent magnet 8 and the magnetic conductive plate assembly 2, which control the size and direction of the electron beam; 4. The crucible 5 and the motor 7, the main shaft assembly. When there are multiple crucibles 5, the crucible 5 is driven and positioned by the motor 7; 5. The water-cooled jacket assembly 6, which cools the crucible 5 and the electron gun; 6. The electron gun base and the high-voltage insulation assembly, which provide support and insulation for the entire system. The traditional electron gun cannot be used in applications where higher film quality is required, especially when the system vacuum needs to reach ultra-high vacuum (the background vacuum is lower than 10-7 Pa). The main problems are:

[0005] 1. Water leakage is likely to occur at the water pipe joints;

[0006] 2. The main shaft of the crucible motor is a rotating moving part, and its dynamic sealing structure has a large leakage rate, making it impossible for the system vacuum to reach the ultra-high vacuum requirement;

[0007] 3. The vacuum seal of the entire electron gun uses rubber ring seals, and the system vacuum still cannot reach the ultra-high vacuum level. Therefore, those skilled in the art have provided an ultra-high vacuum electron gun for electron beam evaporation coating to solve the problems raised in the above background technology. Utility Model Content

[0008] To solve the above technical problems, the present utility model provides an ultra-high vacuum electron gun for electron beam evaporation coating, including an electron gun base. The crucible is installed at the front end of the electron gun base, and the electron emission component is loaded inside the electron gun base. All the sealing components of the electron emission component are sealed with metal oxygen-free copper rings, greatly reducing the leakage rate. The water-cooled jacket assembly is fixedly installed at the lower end of the crucible, and a cooling water pipe joint is fixedly installed at the front end of the water-cooled jacket assembly. Compared with the traditional water outlet position which is changed from the side to the front, the structure is more compact and space-saving. The cooling water pipe joint adopts the VCR connection method, with more reliable connection and higher sealing performance.

[0009] Preferably: The Y coil is fixedly installed at the lower end of the electron gun base.

[0010] Preferably: The X coil is fixedly installed at the side end of the crucible.

[0011] Preferably: The scanning coil assembly is fixedly installed in the upper part inside the crucible, and the X coil, the Y coil, and the scanning coil assembly are used in cooperation to change the position of the electron beam in the crucible.

[0012] Preferably: A permanent magnet is arranged at the lower end inside the crucible.

[0013] Preferably: The magnetic conductive plate assembly is fixedly installed at the upper end of the crucible, and the magnetic conductive plate assembly and the permanent magnet are used to control the size and direction of the electron beam.

[0014] Technical effects and advantages of the present utility model:

[0015] 1. When the present utility model is in use, the crucible motor is removed, eliminating the leakage caused by dynamic seals, and a metal oxygen-free copper ring is used to seal each sealing component of the electron gun, greatly reducing the leakage rate, enabling the entire coating equipment system to meet the requirements of ultra-high vacuum, and the background vacuum degree of the system can reach below 6.67×10-7 Pa.

[0016] 2. When the present utility model is in use, a cooling water pipe joint using the VCR connection method is adopted, ensuring more reliable connection while having higher sealing performance, and the overall device structure is more compact, saving space. Description of the drawings

[0017] Figure 1 is a schematic structural diagram of a traditional electron gun provided by the present application;

[0018] Figure 2 is a schematic diagram of the working principle of the electron gun provided by the present application;

[0019] Figure 3 is a schematic structural diagram provided by the present application;

[0020] In the figure: 1. Electron emission component; 2. Magnetic conductive plate component; 3. X coil; 4. Y coil; 5. Crucible; 6. Water-cooled jacket component; 7. Motor; 8. Permanent magnet; 9. Cooling water pipe joint; 10. Scanning coil component; 11. Metal oxygen-free copper ring; 12. Electron gun base. Detailed implementation manners

[0021] The following further describes the present utility model in detail with reference to the drawings and specific implementation manners. The embodiments of the present utility model are given for the purpose of illustration and description, and are not exhaustive or limit the present utility model to the disclosed form. Many modifications and variations are obvious to those of ordinary skill in the art. The embodiments are selected and described to better illustrate the principles and practical applications of the present utility model, and enable those of ordinary skill in the art to understand the present utility model and thus design various embodiments with various modifications suitable for specific purposes.

[0022] Please refer to the figure. In this embodiment, a ultra-high vacuum electron gun for electron beam evaporation coating is provided, which includes an electron gun base. A crucible is installed at the front end of the electron gun base, and an electron emission component is loaded inside the electron gun base. All the sealing components of the electron emission component are sealed with metal oxygen-free copper rings, greatly reducing the leakage rate. A Y coil is fixedly installed at the lower end of the electron gun base, an X coil is fixedly installed at the side end of the crucible, and a scanning coil assembly is fixedly installed at the upper part inside the crucible. By using the X coil, Y coil and the scanning coil assembly in cooperation, the position of the electron beam in the crucible can be changed. A permanent magnet is arranged at the lower end inside the crucible, and a magnetic conduction plate assembly is fixedly installed at the upper end of the crucible. Through the cooperation of the magnetic conduction plate assembly and the permanent magnet, the size and direction of the electron beam can be controlled;

[0023] A water-cooling jacket assembly is fixedly installed at the lower end of the crucible, and a cooling water pipe joint is fixedly installed at the front end of the water-cooling jacket assembly. Compared with the traditional water outlet position which is changed from the side to the front, the structure is more compact and saves more space. The cooling water pipe joint adopts a VCR connection method, with more reliable connection and higher sealing performance.

[0024] The working principle of the present utility model is as follows:

[0025] When the present utility model is in use, compared with the traditional electron gun, the crucible motor is removed to eliminate the leakage caused by dynamic sealing, and metal oxygen-free copper rings are used to seal all the sealing components of the electron gun, greatly reducing the leakage rate, enabling the entire coating equipment system to meet the ultra-high vacuum degree requirement. The background vacuum degree of the system can reach below 6.67×10-7Pa. At the same time, the cooling water pipe joint adopting the VCR connection method ensures more reliable connection and higher sealing performance, and the overall device structure is more compact and saves space, enabling the electron gun of this device to be applied to the research and development of high-end cutting-edge technologies such as magnetic material thin films, spin electron thin films, Josephson junctions, giant magnetoresistance, and nano-devices.

[0026] Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art and related fields based on the embodiments in the present utility model without creative efforts shall fall within the protection scope of the present utility model. The structures, devices and operation methods not specifically described and explained in the present utility model, unless otherwise specified and limited, are implemented according to the conventional means in the art.

Claims

1. An ultra-high vacuum electron gun for electron beam evaporation coating, comprising an electron gun base (12), characterized in that: A crucible (5) is installed at the front end of the electron gun base (12), an electron emission assembly (1) is loaded in the electron gun base (12), each sealing component of the electron emission assembly (1) is sealed by a metal oxygen-free copper ring (11), a water cooling jacket assembly (6) is fixedly installed at the lower end of the crucible (5), a cooling water pipe joint (9) is fixedly installed at the front end of the water cooling jacket assembly (6), and the cooling water pipe joint (9) adopts a VCR connection method.

2. The ultra-high vacuum electron gun for electron beam evaporation coating according to claim 1, characterized in that: A Y coil (4) is fixedly mounted on the lower end of the electron gun base (12).

3. The ultra-high vacuum electron gun for electron beam evaporation coating according to claim 1, characterized in that: An X coil (3) is fixedly mounted on the side end of the crucible (5).

4. The ultra-high vacuum electron gun for electron beam evaporation coating according to claim 3, characterized in that: A scanning coil assembly (10) is fixedly mounted on the upper inner portion of the crucible (5).

5. The ultra-high vacuum electron gun for electron beam evaporation coating according to claim 4, characterized in that: A permanent magnet (8) is arranged at the lower end of the crucible (5).

6. The ultra-high vacuum electron gun for electron beam evaporation coating according to claim 5, characterized in that: A magnetic conductive plate assembly (2) is fixedly mounted on the upper end of the crucible (5).

Images