A diamond deposition apparatus

Abstract

The present application relates to the technical field of coating, and particularly provides a diamond deposition device, wherein a deposition chamber is arranged in the deposition device, and the deposition device further comprises a magnetic control unit, which is used for generating a variable magnetic field in the deposition chamber, and the magnetic field controls the ion trajectory in the deposition chamber when changing, so that the ion trajectory is directed to bombard the substrate surface of a workpiece; the present application cooperatively regulates the magnetic field distribution through multiple groups of coils, drives the carbon ions to direct bombard the substrate surface, effectively improves the deposition rate of the diamond film and the uniformity of the film distribution, and improves the quality of the diamond coating.

Description

Technical Field

[0001] This invention relates to the field of coating technology, and more particularly to a diamond deposition apparatus. Background Technology

[0002] Diamond films, with their ultra-high hardness (HV10000-15000), excellent light transmittance (infrared transmittance >90%), and resistance to acid and alkali corrosion, have become the optimal choice for surface modification of optical components.

[0003] However, existing diamond deposition equipment has some shortcomings, such as poor deposition uniformity. Traditional single-source deposition (such as microwave plasma CVD) can only achieve a film thickness uniformity of ±5% for planar parts, while the uniformity error for complex curved surfaces (such as aspherical lenses) exceeds 15%. To solve the above problems, this invention discloses a diamond deposition equipment. Summary of the Invention

[0004] The purpose of this invention is to provide a diamond deposition device to solve the problem of poor coating uniformity in current diamond coating equipment.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A diamond deposition apparatus, wherein a deposition chamber is provided within the deposition apparatus, and the deposition apparatus further includes:

[0007] A magnetron control unit is used to generate a variable magnetic field in the deposition chamber, which controls the trajectory of ions in the deposition chamber as the magnetic field changes, causing them to bombard the substrate surface of the workpiece in a directional manner.

[0008] Furthermore, the magnetic control unit includes:

[0009] A first coil group and a second coil group are coaxially arranged and located on both sides of the outer periphery of the deposition chamber. The first coil group and the second coil group are coaxially arranged with the deposition chamber, so that a uniform axial magnetic field is formed inside the deposition chamber.

[0010] A deflection coil assembly is used to generate a magnetic field orthogonal to the axial magnetic field formed by the first coil assembly and the second coil assembly, for deflecting ion trajectories.

[0011] Furthermore, the first coil group and the second coil group are a pair of coil structures with identical parameters, and the distance between the first coil group and the second coil group is equal to the radius of the first coil group.

[0012] Furthermore, the first coil group includes:

[0013] The coil housing has an annular cavity structure and is made of a non-ferromagnetic material.

[0014] The main coil is a spirally wound wire, and an insulating encapsulation layer is provided between the inner wall of the coil housing and the main coil.

[0015] Furthermore, an inner partition is provided inside the coil housing. The inner partition is annular, and a cooling channel is formed between the outer side of the inner partition and the inner wall of the coil housing. A circulating cooling medium is provided in the cooling channel.

[0016] Furthermore, a main heat dissipation pipe is provided in the cooling channel. The main heat dissipation pipe has a spiral copper pipe structure, and thermally conductive material is filled between the main heat dissipation pipe and the cooling channel.

[0017] Furthermore, the magnetic control unit also includes:

[0018] The electrode coils are located inside the deposition chamber. Multiple electrode coils are provided, and the axis of each electrode coil is parallel to the axis of the first coil group. The multiple electrode coils are evenly distributed around the axis of the deposition chamber in the circumferential direction.

[0019] Furthermore, the pole coil has a conductor rod structure, and the current directions of adjacent pole coils are opposite.

[0020] Furthermore, a heat-insulating shell is provided on the outside of the pole coil.

[0021] Furthermore, a circulating cooling channel is provided inside the pole coil, through which the cooling medium cools the pole coil.

[0022] In summary, the present invention has the following advantages compared with the prior art:

[0023] The diamond deposition equipment disclosed in this invention uses multiple sets of coils to coordinate and regulate the magnetic field distribution, driving carbon ions to bombard the substrate surface in a directional manner, effectively improving the deposition rate and uniformity of the diamond film distribution, and enhancing the quality of the diamond coating. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of the diamond deposition equipment disclosed in an embodiment of the present invention.

[0025] Figure 2 This is a schematic diagram of the internal structure of the diamond deposition equipment disclosed in an embodiment of the present invention.

[0026] Figure 3 This is a top view of the diamond deposition apparatus disclosed in an embodiment of the present invention.

[0027] Figure 4 for Figure 3 A cross-sectional view of BB.

[0028] Figure 5 This is a schematic diagram of the deposition chamber in the diamond deposition equipment disclosed in an embodiment of the present invention.

[0029] Figure 6 This is a top view of the deposition chamber in the diamond deposition apparatus disclosed in an embodiment of the present invention.

[0030] Figure 7 for Figure 6 Sectional view of AA.

[0031] Figure 8 for Figure 7 A magnified view of a section at point I.

[0032] Figure 9 This is a schematic diagram of the structure of the magnetron unit in the diamond deposition equipment disclosed in an embodiment of the present invention.

[0033] Figure 10 This is a top view of the magnetron control unit in the diamond deposition apparatus disclosed in an embodiment of the present invention.

[0034] Figure 11 This is a full cross-sectional view of the neutron coil assembly in the diamond deposition equipment disclosed in an embodiment of the present invention.

[0035] Figure 12 This is a schematic diagram of the lower target unit in the diamond deposition equipment disclosed in an embodiment of the present invention.

[0036] Figure label:

[0037] 100. Outer shell; 200. Deposition chamber; 201. Viewing window; 210. Top cover plate; 220. Enclosure plate; 230. Bottom plate; 300. Upper target unit; 400. Lower target unit; 410. Lower target body; 420. Lower target rotating component; 421. Lower target support shaft; 422. Gear motor; 423. Lower target rotating seat; 424. Steering gearbox; 500. Vacuum pumping unit; 600. Gas supply unit; 700. Cooling unit; 800. Lifting unit; 900. Magnetic control unit; 910. First coil group; 911. Coil housing; 912. Inner partition plate; 913. Main coil; 914. Main heat dissipation pipe; 920. Second coil group; 930. Deflection coil group; 940. Pole coil; 941. Heat insulation housing. Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0039] like Figures 1 to 5 As shown, an embodiment of the present invention provides a diamond deposition apparatus, the deposition apparatus including a housing 100, a deposition chamber 200, an upper target unit 300, a lower target unit 400, a vacuum unit 500, a gas supply unit 600, a cooling unit 700, a lifting unit 800, and a magnetic control unit 900. The deposition chamber 200 has an internal hollow structure. Both the upper target unit 300 and the lower target unit 400 have target structures disposed inside the deposition chamber 200 for realizing the reaction of the internal gas. The vacuum unit 500 is used to extract the gas inside the deposition chamber 200 to form a vacuum environment. The gas supply unit 600 is used to introduce reactive gas into the deposition chamber 200. The cooling unit 700 is used to cool the target structures of the upper target unit 300 and the lower target unit 400 to prevent them from being damaged by high temperature during operation. The lifting unit 800 is used to drive the target structure on the upper target unit 300 to move up and down to adjust the distance between it and the lower target plate, and at the same time open the upper cover plate 210 of the deposition chamber 200 to facilitate the placement of materials. The magnetocontrol unit 900 is located on the deposition chamber 200 and is used to generate a magnetic field to regulate the plasma distribution and improve the deposition uniformity of diamond films.

[0040] In this embodiment, during diamond thin film deposition, the upper cover plate 210 is first opened via the lifting unit 800, and the material to be deposited is placed in the deposition chamber 200. The chamber is then closed and sealed, and a vacuum is drawn to the required pressure via the vacuum unit 500. A mixed gas flow of carbon-containing gas and hydrogen is then introduced via the gas supply unit 600, with the flow ratio adjusted to a set value. The cooling unit 700 is activated to continuously cool the upper target unit 300 and the lower target unit 400. The upper target unit 300 and the lower target unit 400 are activated, causing the gas within them to react and generate plasma. A magnetic field is applied via the magnetron control unit 900 to regulate the plasma density distribution, concentrating the reaction area on the deposition surface and improving the diamond thin film growth quality. Simultaneously, the magnetron control unit 900 controls the ion deflection direction, ensuring that carbon ions in the plasma bombard the substrate surface along a predetermined trajectory, thus improving the uniformity of thin film formation.

[0041] The diamond deposition equipment disclosed in this invention uses multiple sets of coils to coordinate and regulate the magnetic field distribution, driving carbon ions to bombard the substrate surface in a directional manner, effectively improving the deposition rate and uniformity of the diamond film distribution, and enhancing the quality of the diamond coating.

[0042] Specifically, in this embodiment, the outer shell 100, deposition chamber 200, upper target unit 300, lower target unit 400, vacuum unit 500, gas supply unit 600, cooling unit 700, and lifting unit 800 are all existing technologies. For example, in this embodiment, the outer shell 100 is a box structure composed of profiles and aluminum plates welded together, possessing good structural strength and sealing performance. The deposition chamber 200 is a cylindrical cavity structure, including an upper cover plate 210, a surrounding plate 220, and a bottom plate 230. The upper cover plate 210 is fixedly connected to the lifting unit 800. At the output end of the 00, the surrounding plate 220 and the bottom plate 230 are fixedly connected to the outer shell 100. The surrounding plate 220 is a cylindrical shape with openings at both ends, and the bottom plate 230 is a flat plate structure. The surrounding plate 220 and the bottom plate 230 are sealed together by welding. The upper cover plate 210 is pressed against one end of the deposition chamber 200 by the lifting unit 800. The upper cover plate 210 and the surrounding plate 220 are sealed together by a sealing ring to ensure that the cavity remains highly sealed during the deposition process and to prevent external impurities from entering and affecting the purity of the film. The target structures in the upper target unit 300 and the lower target unit 400 are either radio frequency power-driven plasma generators or microwave source-driven plasma generators, and the working mode can be selected according to process requirements. The target mechanisms of the upper target unit 300 and the lower target unit 400 are arranged opposite each other, so that the plasma forms a symmetrical distribution in the cavity, enhancing the stability and uniformity of the reaction area and effectively avoiding local overheating or uneven deposition. The vacuum pumping unit 500 is connected to the deposition chamber 200, and is used to precisely extract the gas inside the deposition chamber 200, thereby achieving precise control of the gas pressure inside the deposition chamber 200 and ensuring a stable deposition environment. The gas supply unit 600 includes a gas mixing unit and a mass flow controller, which can precisely introduce carbon-containing gas and hydrogen in a preset ratio and adjust the gas flow rate in real time to match the needs of different growth stages. The cooling unit 700 is a water-cooling unit, used to circulate water to the target structures on the upper target unit 300 and the lower target unit 400 to achieve internal cooling of the target structures, prevent target material deformation or performance degradation due to high temperature, and ensure continuous and stable plasma generation. The lifting unit 800 is a lead screw lifting structure in the prior art. The output end of the lifting unit 800 is fixedly connected to the upper cover plate 210 and is used to control the lifting of the upper cover plate 210. The lifting unit 800 is also provided with a sub-lifting component, which is used to control the precise vertical positioning of the target structure of the upper target unit 300, ensuring that the distance between the target structure and the substrate is adjustable to meet the growth requirements of diamond films of different thicknesses, while optimizing the ion bombardment energy distribution. The sub-lifting component works in conjunction with the lifting unit 800 to achieve multi-degree-of-freedom adjustment and improve process flexibility.The sub-lifting assembly is a lead screw lifting structure, and its output end is fixedly connected to the target structure of the upper target unit 300.

[0043] The deposition chamber 200 is equipped with a viewing window 201 made of high-temperature resistant quartz glass. This window allows for real-time observation of the internal reaction state during deposition, facilitating operator monitoring of plasma glow stability and film growth, and enabling timely adjustment of process parameters to ensure film quality. The connection between the viewing window 201 and the chamber utilizes a metal sealing ring and flange clamping structure to ensure reliable sealing under high-temperature, high-vacuum conditions. Simultaneously, the inner surface of the viewing window 201 can be coated with an anti-reflective coating to improve optical transmittance and enhance observation clarity. Combined with an external high-speed camera system, this allows for dynamic recording and analysis of the deposition process. Furthermore, the axial position of the viewing window 201 is aligned with the plasma luminescence region, ensuring the observation angle covers the core reaction area, facilitating the capture of glow intensity changes and discharge uniformity. Combined with a spectral diagnostic system, the emission lines of active groups, such as CH (431.5 nm) and Hα (656.3 nm), can be monitored in real time, thereby retrieving plasma density and electron temperature distribution, providing data support for process optimization.

[0044] Preferably, the upper target unit 300 and the lower target unit 400 adopt a symmetrical electrode structure design, which, together with the radio frequency power supply, excites and forms a high-density capacitively coupled plasma in the deposition chamber 200, enhancing the ionization efficiency of carbon-containing active groups. By adjusting the radio frequency power and gas ratio, the sp³ bond content during diamond film growth can be effectively controlled, improving film hardness and thermal conductivity. Simultaneously, a substrate heating system is integrated at the bottom of the deposition chamber 200, employing a combination of infrared radiation and back-facing ohmic heating to control substrate temperature uniformity within ±5℃, meeting the requirements for high-quality diamond heteroepitaxial growth.

[0045] As a preferred embodiment of this example, Figure 12 As shown, the lower target unit 400 includes a lower target body 410 and a lower target rotating component 420. The lower target body 410 is connected to the position inside the deposition chamber 200 corresponding to the upper target unit 300. The lower target rotating component 420 is mounted on the outer shell 100. The lower target rotating component 420 is used to drive the lower target body 410 to rotate. During diamond deposition, the lower target rotating component 420 controls the rotation of the lower target body 410 according to the working parameters of the magnetocontrol unit 900 to avoid the bombardment blind zone of carbon ions.

[0046] Specifically, in this embodiment, the lower target rotating component 420 includes a lower target support shaft 421 and a reduction motor 422. The end of the lower target support shaft 421 is fixedly connected to the lower target body 410, and the lower target support shaft 421 is rotatably connected to the outer shell 100. As in this embodiment, the lower target support shaft 421 passes through the base plate 230 and is rotatably connected to the base plate 230. The bottom of the base plate 230 is fixed with a lower target rotating seat 423 by bolts. The lower target support shaft 421 is rotatably connected to the lower target rotating seat 423 by bearings. The lower target support shaft 421 and the lower target rotating seat 423 are connected by a thrust bearing to support the lower target support shaft 421. The reduction motor 422 is connected to the lower target support shaft 421 through a steering gearbox 424 to achieve right-angle power transmission. The output shafts of the reduction motor 422 and the steering gearbox 424 are rigidly connected by a coupling to ensure the accuracy and reliability of power transmission.

[0047] The geared motor 422 is fixedly mounted on the mounting base of the housing 100 via a flange, and its output shaft is coaxially connected to the input shaft of the steering gearbox 424. The steering gearbox 424 adopts a helical gear transmission structure, converting the horizontal rotational motion output by the geared motor 422 into vertical rotation, driving the lower target support shaft 421 and the lower target body 410 fixed thereon to rotate at a uniform speed during the deposition process. This rotational motion can effectively eliminate the carbon ion bombardment blind zone caused by the asymmetry of the magnetic field distribution or plasma flow field, ensuring the consistency of the ion flux received in each area of ​​the substrate surface, and significantly improving the radial uniformity of the diamond film thickness.

[0048] The geared motor 422 is equipped with an encoder to provide real-time feedback of the rotational speed signal to the control system, enabling stepless and precise adjustment of the target body 410's rotational speed within the range of 1 to 30 rpm to adapt to process requirements under different deposition rates and magnetic field configurations. Simultaneously, the target support shaft 421 integrates a rotary water connector for supplying cooling water circulation medium to the rotating target body 410, ensuring cooling during rotation. The water circulation system is connected to external pipelines via the rotary water connector.

[0049] As a preferred embodiment of this example, Figures 5 to 8 As shown, the magnetic control unit 900 includes a first coil group 910, a second coil group 920, and a deflection coil group 930. The first coil group 910 and the second coil group 920 are both ring coils. The first coil group 910 and the second coil group 920 are coaxially arranged and located on both sides of the outer periphery of the enclosure plate 220. The first coil group 910 and the second coil group 920 are coaxially arranged with the deposition chamber 200, so that a uniform axial magnetic field is formed inside the deposition chamber 200, which effectively confines the diffusion path of the plasma.

[0050] Preferably, the distance between the first coil group 910 and the second coil group 920 is equal to the radius of the first coil group 910, and the two form a pair of Helmholtz coil structures, so that the magnetic field is highly uniform in the central region of the cavity, further improving the consistency of plasma density distribution, thereby improving the growth uniformity and crystal quality of diamond film.

[0051] In this embodiment, the first coil group 910 and the second coil group 920 are a pair of coil structures with the same parameters. Multiple groups of the second coil group 920 can also be provided. The first coil group 910 and multiple groups of the second coil group 920 are coaxially arranged.

[0052] The first coil group 910 and the second coil group 920 generate a uniform and stable axial magnetic field inside the deposition chamber 200, causing electrons to rotate around the magnetic field lines, thereby confining the plasma in the central region of the cavity, preventing it from recombinating with the cavity wall too early, and improving the plasma density and stability.

[0053] The deflection coil group 930 is used to deflect the plasma. The magnetic field generated by the deflection coil group 930 is orthogonal to the axial magnetic field formed by the first coil group 910 and the second coil group 920, forming a composite magnetic field structure. This structure can directionally control the trajectory of the plasma, realize the local focusing and deflection of the plasma beam, and thus optimize the deposition path of carbon ions on the substrate surface.

[0054] Preferred, such as Figure 8 As shown, the first coil group 910 includes a coil housing 911 and a main coil 913. The coil housing 911 has an annular cavity structure and is made of a non-ferromagnetic material. The main coil 913 is a spirally wound wire. An insulating encapsulation layer is provided between the inner wall of the coil housing 911 and the main coil 913. For example, the insulating encapsulation layer is an insulating and thermally conductive material to ensure the electrical insulation and thermal stability of the coil under high power operation.

[0055] Preferably, the coil housing 911 is further provided with an inner partition 912. The inner partition 912 is annular, and a cooling channel is formed between the outer side of the inner partition 912 and the inner wall of the coil housing 911 for cooling the main coil 913. The cooling medium circulates in the cooling channel to effectively remove the Joule heat generated when the coil is working and maintain the thermal balance of the system.

[0056] Preferably, a main heat dissipation pipe 914 is provided in the cooling channel. The main heat dissipation pipe 914 has a spiral copper pipe structure. The space between the main heat dissipation pipe 914 and the cooling channel is filled with a thermally conductive material, such as silicone grease. The main heat dissipation pipe 914 is connected to the cooling unit 700. The cooling unit 700 controls the cooling medium to enter the interior of the main heat dissipation pipe 914.

[0057] In this embodiment, the deflection coil group 930 is composed of multiple Helmholtz coil pairs. The deflection coil group 930 is evenly distributed around the periphery of the deposition chamber 200. The coils in the deflection coil group 930 work together to achieve multi-directional dynamic control of the plasma flow, thereby improving the controllability and uniformity of thin film deposition.

[0058] The deflection coil group 930 is existing technology. The deflection coil group 930 is fixed to the outer wall of the deposition chamber 200 by screws, welding or bonding. In this embodiment, the deflection coil group 930 includes three pairs of Helmholtz coils.

[0059] Both the first coil group 910 and the deflection coil group 930 are hollow coil structures.

[0060] As a preferred embodiment of this example, Figures 9 to 11 As shown, the magnetocontrol unit 900 further includes pole coils 940 located inside the deposition chamber 200. Multiple pole coils 940 are provided, and their axes are parallel to the axis of the first coil group 910. These multiple pole coils 940 are evenly distributed circumferentially around the axis of the deposition chamber 200. The pole coils 940 are distributed between the target structure and the deposition chamber 200, with adjacent pole coils 940 having opposite current directions. The magnetic field of the pole coil 940 at the center of the deposition chamber 200 is zero, but a radially increasing magnetic field is generated in the region away from the center of the deposition chamber 200 to radially compress or stretch the plasma.

[0061] For example, in this embodiment, four pole coils 940 are provided, and the four pole coils 940 are symmetrically distributed at 90 degrees. The four pole coils 940 are numbered 1, 2, 3, and 4 in a clockwise direction, and the current is: 1 (inflow), 2 (outflow), 3 (inflow), and 4 (outflow).

[0062] like Figure 9 As shown, the pole coil 940 is a conductor rod structure, and the pole coil 940 is fixedly connected to the upper cover plate 210.

[0063] Preferably, a heat insulation shell 941 is also provided on the outside of the pole coil 940. The heat insulation shell 941 is a heat insulation material used to block the heat conduction between the pole coil 940 and the deposition chamber 200, prevent high temperature from spreading to the external structure, and ensure the stability of the system's thermal field distribution.

[0064] Preferably, a circulating cooling channel is provided inside the pole coil 940, through which the cooling medium directly cools the pole coil 940, preventing the conductor rod from overheating due to Joule heat accumulation and affecting the stability of the magnetic field. The circulating cooling channel has a U-shaped structure, extends along the axial direction of the pole coil 940, and connects to the cooling unit 700.

[0065] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0066] It should be understood that although the terms first, second, third, etc., may be used in this invention to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first information may also be referred to as second information without departing from the scope of this invention, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to a determination."

[0067] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A diamond deposition apparatus, wherein the deposition apparatus is provided with a deposition chamber, characterized in that, The deposition apparatus also includes: A magnetron control unit is provided to generate a variable magnetic field in the deposition chamber. This magnetic field, when varying, controls the ion trajectory within the deposition chamber, directing it to bombard the substrate surface of the workpiece. The magnetron control unit includes a first coil group, a second coil group, and a deflection coil group. The first and second coil groups are coaxially arranged and located on opposite sides of the outer periphery of the deposition chamber, forming a uniform axial magnetic field inside the chamber. The deflection coil group generates a magnetic field orthogonal to the axial magnetic field formed by the first and second coil groups, deflecting the ion trajectory. The first and second coil groups are a pair of coil structures with identical parameters, and the distance between them is equal to the radius of the first coil group. The first coil assembly includes a coil housing and a main coil. The coil housing has an annular cavity structure and is made of a non-ferromagnetic material. The main coil is a spirally wound wire. An insulating encapsulation layer is provided between the inner wall of the coil housing and the main coil. An inner partition is also provided inside the coil housing. The inner partition is annular. A cooling channel is formed between the outer side of the inner partition and the inner wall of the coil housing. A circulating cooling medium is provided in the cooling channel. A main heat dissipation pipe is provided in the cooling channel. The main heat dissipation pipe has a spiral copper pipe structure. Thermally conductive material is filled between the main heat dissipation pipe and the cooling channel. The magnetron control unit also includes pole coils located inside the deposition chamber. Multiple pole coils are provided, and the axis of each pole coil is parallel to the axis of the first coil group. The multiple pole coils are evenly distributed around the axis of the deposition chamber in the circumferential direction. Each pole coil has a conductor rod structure, and the current directions of adjacent pole coils are opposite.

2. The diamond deposition equipment according to claim 1, characterized in that, A heat-insulating shell is also provided on the outside of the pole coil.

3. The diamond deposition equipment according to claim 1, characterized in that, A circulating cooling channel is provided inside the pole coil, and the cooling medium cools the pole coil through the circulating cooling channel.

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