Auxiliary device utilizing microwave deposition plasma source
By improving the shape of the waveguide inner wall and setting a disturbance, the problem of uneven microwave plasma energy distribution was solved, and uniform deposition of the coating was achieved, which is applicable to carbon-based and silicon-based coatings, etc.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- POLESTAR PLASMA TECH CO LTD
- Filing Date
- 2025-05-27
- Publication Date
- 2026-04-24
AI Technical Summary
Existing microwave plasma introduction methods create standing waves within the waveguide structure, leading to uneven energy distribution and uneven coating deposition.
An auxiliary device is designed to increase the scattering ratio and control the phase of microwave energy by improving the shape of the inner wall of the waveguide and setting a disturbance, so as to ensure uniform energy distribution. Quartz glass is used to isolate atmospheric pressure and vacuum, thereby exciting uniform plasma.
It achieves uniform deposition of coatings on the workpiece surface, improving the uniformity and consistency of the coating, and is suitable for carbon-based and silicon-based coatings, etc.
Smart Images
Figure CN224160691U_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of plasma deposition technology, specifically relating to an auxiliary device for using a microwave deposition plasma source. Background Technology
[0002] In physical vapor deposition (PVD) processes, a gas deposition source is introduced into the furnace to grow specific coatings, such as carbon-based and silicon-based coatings. However, existing gas deposition processes primarily rely on sputtering or evaporation of solid targets, lacking effective methods for uniformly introducing the gas deposition source. Traditional microwave plasma deposition mainly employs plasma discharge as the introduction method. Specifically, plasma discharge occurs within the microwave transmission structure, where the container or space carrying the plasma is part of the microwave transmission structure or waveguide structure. However, this method creates standing wave structures within the waveguide, resulting in low refracted energy levels at wave nodes and high refracted energy levels between wave nodes. This causes the plasma excited within the furnace to exhibit periodic concentration variations along the waveguide propagation direction, leading to uneven energy distribution and ultimately, non-uniform deposition. Utility Model Content
[0003] The purpose of this invention is to solve the problems in the background technology and provide an auxiliary device for microwave deposition plasma source. This auxiliary device not only improves the step shape of the inner wall of the waveguide, making the inner wall shape of the waveguide asymmetrical in the microwave transmission direction, but also makes the microwave more uniformly refracted towards the furnace body when it propagates in the waveguide along the energy injection direction, thus ensuring the uniformity of workpiece deposition.
[0004] The objective of this utility model is achieved through the following technical solution:
[0005] An auxiliary device for a microwave deposition plasma source includes a vacuum furnace and an auxiliary plasma source. The inner cavity of the vacuum furnace is cylindrical, and a rotating frame for placing workpieces is installed inside the vacuum furnace. The auxiliary plasma source is connected to the vacuum furnace and includes a waveguide. Energy is injected from the left side of the waveguide, and a reflection matching network is connected to the right side of the waveguide. A quartz glass is provided above the waveguide to isolate the atmospheric pressure waveguide and the vacuum cavity. A disturbance for adjusting the size of the microwave waveguide is provided on the inner side of the waveguide at the position of the quartz glass window.
[0006] The disturbance includes a central fin and disturbance blocks. The central fin is vertically arranged, and the disturbance blocks are distributed on both sides of the central fin. The disturbance blocks on both sides are staggered and aligned along the central fin.
[0007] The beneficial effects of the auxiliary device for microwave deposition plasma source provided by this utility model are:
[0008] (1) By setting an auxiliary plasma source and a disturbance device, the scattering ratio and scattering direction of waveguide energy to the vacuum cavity can be increased. Combined with the rotating frame inside the vacuum furnace, the uniformity of the overall coating can be guaranteed.
[0009] (2) By installing quartz glass on the waveguide, the vacuum can be isolated and plasma can be reliably excited at the same time;
[0010] (3) By setting a disturbance inside the waveguide, the scattering ratio of microwaves when propagating along the energy injection direction of the waveguide can be increased, and the phase of the scattered microwaves can be controlled to ensure that the scattered microwaves diffuse in a direction perpendicular to the surface of the quartz glass, thereby ensuring the uniformity of plasma concentration. Attached Figure Description
[0011] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0012] Figure 1 This is a structural schematic diagram provided for an embodiment of the present utility model.
[0013] Figure 2 This is a schematic diagram of the structure of the auxiliary plasma source provided in an embodiment of the present invention.
[0014] Figure 3 A schematic diagram of the disturbance provided in an embodiment of this utility model.
[0015] The markings in the diagram are: 1. Vacuum furnace body; 2. Rotary frame; 3. Auxiliary plasma source; 4. Waveguide; 5. Quartz glass; 6. Disruptor; 61. Central fin; 62. Disruptor block. Detailed Implementation
[0016] like Figures 1-3As shown, the auxiliary device for microwave deposition plasma source provided in this embodiment includes a vacuum furnace body 1 and an auxiliary plasma source 3. The inner cavity of the vacuum furnace body 1 is cylindrical, and a vacuum interface is installed on the furnace body. A rotating frame 2 for placing workpieces is installed inside the vacuum furnace body 1. The auxiliary plasma source 3 is connected to the vacuum furnace body 1, and the length of the plasma source 3 is matched with the height of the vacuum furnace body 1. The auxiliary plasma source 3 includes a waveguide 4, which is composed of a 2.45 GHz microwave waveguide. Microwave power is injected from the left side of the waveguide 4, and a reflection matching network is connected to the right side of the waveguide 4. An isolation constant is provided above the waveguide 4. The quartz glass 5, which is used to pressurize the waveguide and vacuum cavity, allows microwave energy injected from the left side of the waveguide 4 to propagate to the right within the waveguide 4 and diffuse into the vacuum furnace 1, which is being evacuated, through the quartz glass 5. At this time, the quartz glass 5 has two functions: isolating the vacuum and separating the microwave plasma excitation conditions. Specifically, the furnace body above the quartz glass 5 is in a vacuum state, while the waveguide 4 below the quartz glass 5 is in a normal pressure state. Under normal pressure, the mean free path of gas molecules is of varying lengths, making them difficult to excite in a microwave field. However, under vacuum conditions, when the gas pressure is reduced to 1 Pa, plasma can be reliably excited. A perturbator 6, used to adjust the size of the microwave waveguide, is installed on the inner side of the waveguide 4 at the position of the window of the quartz glass 5. The perturbator 6 increases the proportion of microwaves scattered from the quartz glass 5 towards the vacuum furnace 1 as they propagate along the energy injection direction. It also controls the phase of the scattered microwaves, ensuring that they diffuse in a direction perpendicular to the surface of the quartz glass 5, rather than being affected by continuously changing phase variations that cause the wavefield direction to be non-perpendicular. Furthermore, by customizing the size of the perturbator 6, the power density of the scattered microwaves in the longitudinal direction of the waveguide can be adjusted, thereby achieving uniform energy density throughout the longitudinal direction of the ion source. To ensure the uniformity of plasma concentration, the perturber 6 includes a central fin 61 and perturber blocks 62. The central fin 61 is vertically arranged, and the perturber blocks 62 are distributed on both sides of the central fin 61. The perturber blocks 62 on both sides are staggered and aligned along the central fin 61. The longitudinal length of the perturber blocks 62 is L, which is half the waveguide wavelength. The central fin 61 is located at the center of the waveguide 4. The protrusion height of the central fin 61 and the perturber blocks 62 corresponds to the required microwave scattering intensity. The optimal state of the perturber 6 is that when the microwave power energy diffuses to the waveguide terminal, it is close to zero or only has very low power and large reflection.
[0017] The method of using this utility model is as follows:
[0018] Preparation: Microwave power is injected from the left side of the auxiliary plasma source 3, which is a 2.45 GHz microwave waveguide. A reflection matching network is connected to the right side. Quartz glass 5 is installed on the upper side of the waveguide to form a vacuum isolation. A disturbance 6 is set on the inner side of the waveguide 4 and the lower surface of the quartz glass 5. The disturbance 6 includes a central fin 61 and multiple disturbance blocks 62. The length L of each disturbance block 62 is equal to half the wavelength of the waveguide. The central fin 61 is located at the center of the waveguide 4. Two rows of disturbance blocks 62 are staggered and aligned along the central fin 61. The protrusion height of the disturbance blocks 62 and the central fin 61 is determined according to the required scattering intensity.
[0019] In use: The workpiece is mounted on the rotating frame 2, and hydrocarbon gas is introduced into the vacuum furnace body 1. When the gas pressure in the vacuum furnace drops to 1 Pa, the injected microwave energy diffuses into the vacuum furnace body 1 through the quartz glass 5, exciting the gas to form plasma. At the same time, the rotating frame 2 rotates, and the workpiece can be uniformly exposed to the plasma, which can ensure the uniformity of the coating. These hydrocarbon plasmas will be deposited on the surface of the workpiece, uniformly forming a carbon-based coating or a silicon-based coating. At the same time, by adjusting the structure of the disturbance 6, the longitudinal distribution of microwave energy can be precisely controlled, further improving the uniformity of the coating.
[0020] This design is not only applicable to carbon-based coatings, but also to coatings from other gas sources, such as silicon and boron coatings, requiring only the replacement of the precursor gas.
[0021] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications and substitutions based on the technical solutions and inventive concepts provided by the present invention should be covered within the scope of protection of the present invention.
Claims
1. An auxiliary device for a microwave deposition plasma source, characterized in that: The system includes a vacuum furnace body (1) and an auxiliary plasma source (3). The inner cavity of the vacuum furnace body (1) is cylindrical. A rotating frame (2) for placing workpieces is installed inside the vacuum furnace body (1). The auxiliary plasma source (3) is connected to the vacuum furnace body (1). The auxiliary plasma source (3) includes a waveguide (4). The energy of the waveguide (4) is injected from the left side. A reflection matching network is connected to the right side of the waveguide (4). A quartz glass (5) is provided above the waveguide (4) to isolate the atmospheric pressure waveguide and the vacuum cavity. A disturbance (6) for adjusting the size of the microwave waveguide is provided on the inner side of the waveguide (4) at the position of the window of the quartz glass (5).
2. The auxiliary device for using a microwave deposition plasma source according to claim 1, characterized in that: The disturbance (6) includes a central fin (61) and disturbance blocks (62). The central fin (61) is vertically arranged, and the disturbance blocks (62) are distributed on both sides of the central fin (61). The disturbance blocks (62) on both sides are misaligned and aligned along the central fin (61).