A PEO coating apparatus for semiconductor chamber components

Abstract

This invention relates to the field of surface treatment technology for semiconductor manufacturing equipment, specifically disclosing a PEO coating device for semiconductor cavity components. The device includes a PEO treatment tank, a workpiece body, a clamping assembly, and a lifting mechanism for driving the clamping assembly in and out of the PEO treatment tank. The clamping assembly includes a clamping top frame, a clamping bottom ring, an inner slide rod, a square tube, an elastic conductive plate, and a holding head. The workpiece body is supported by the clamping bottom ring and achieves adaptive clamping and conductivity through the elastic conductive plate and the holding head. The device also includes an orientation adjustment component. This device can achieve stable clamping using the workpiece's own weight during the coating process, and releases the clamping when triggered by clamp descent, causing the workpiece to rotate through a certain angle. This changes the positions of the support and clamping points, allowing the previously obscured area to participate in subsequent PEO treatment, reducing local coating defects and thickness unevenness, and improving the integrity and circumferential consistency of the PEO ceramic coating in hollow semiconductor cavity components.

Description

Technical Field

[0001] This invention relates to the field of surface treatment technology for semiconductor manufacturing equipment, and more particularly to a PEO coating device for semiconductor chamber components. Background Technology

[0002] PEO coating, also known as plasma electrolytic oxidation coating or micro-arc oxidation coating, is a surface treatment technology that uses a high-voltage pulsed electric field in an electrolyte to induce plasma discharge and oxidation on the surface of a metal workpiece, thereby generating a ceramic oxide film in situ. For semiconductor cavity components, which are subjected to long-term plasma bombardment, corrosive gas erosion, and particulate contamination control requirements in etching, deposition, and other process environments, it is usually necessary to form a corrosion-resistant, wear-resistant, and relatively stable ceramic oxide coating on the surface of metal components such as aluminum alloys and titanium alloys. Existing PEO coating equipment generally includes an electrolytic treatment tank, a pulsed power supply, a cathode assembly, a workpiece fixture, and an electrolyte circulation system. During processing, the workpiece is fixed on the fixture and immersed in the electrolyte, with the workpiece acting as the anode connected to the pulsed power supply. The cathode assembly is arranged in the treatment tank and connected to the negative terminal of the pulsed power supply. After energization, micro-arc discharge and oxide film growth are generated on the workpiece surface, thereby completing the coating treatment.

[0003] However, when performing PEO coating on cylindrical, tubular, or other hollow shell-shaped semiconductor cavity components, these workpieces typically need to be stably positioned within the treatment tank, and both their outer circumferential surface and inner cavity surface need to be within a relatively effective electric field range. Therefore, existing equipment can improve the treatment conditions of the inner and outer surfaces by using an outer peripheral cathode in conjunction with an inner cathode. However, in actual processing, the workpiece still needs to rely on fixtures for support, clamping, and conductivity. Existing fixtures often use fixed jaws, pressure blocks, support blocks, or fixed conductive contacts to maintain contact with the workpiece. The contact area between the fixture and the workpiece is in a shielded state for a long time throughout the coating process, making it difficult to fully contact the electrolyte and participate in the micro-arc discharge reaction. This can easily lead to local coating defects, thin thickness, or poor surface continuity. Especially for hollow shell-shaped workpieces such as cylindrical and tubular ones, in order to ensure stable positioning or rotation with the fixture, the fixture often needs to continuously press against the side wall or end of the workpiece, keeping the support point, clamping point, and conductive contact point fixed for a long time. This makes it difficult for the shielded area to be effectively compensated in the same processing process, thus affecting the consistency of the circumferential coating and the overall processing quality. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that existing PEO coating equipment, when processing hollow shell-shaped semiconductor cavity components, mainly suffers from the problem of local shading caused by the fixed position of the clamping support, clamping and conductive contact, which easily leads to coating defects in the contact area, thin thickness and affects the circumferential coating consistency of the workpiece. To this end, we propose a PEO coating equipment for semiconductor cavity components.

[0005] To achieve the above objectives, this application adopts the following technical solution: a PEO coating device for semiconductor cavity components, comprising a PEO processing tank, a workpiece body, a fixture assembly, and a lifting mechanism for driving the fixture assembly in and out of the PEO processing tank;

[0006] The fixture assembly includes a fixture top frame that is driven to rise and fall by a lifting mechanism. A fixture bottom ring is provided below the fixture top frame to support the workpiece body. An inner slide rod is installed on the fixture top frame. A square tube corresponding to the inner slide rod is provided on the fixture bottom ring. The lower end of the inner slide rod is movably connected to the inside of the square tube. An elastic conductive plate is installed on the side of the square tube near the workpiece body. A holding head is installed on the elastic conductive plate to abut against the side wall of the workpiece body. The side of the elastic conductive plate near the inner slide rod cooperates with the inclined surface of the inner slide rod. When the square tube moves down relative to the inner slide rod, the elastic conductive plate is pressed and bends outward.

[0007] It also includes a position adjustment component, which includes a roller shaft rotatably disposed in the bottom ring of the fixture. The roller shaft is provided with a support roller for supporting the workpiece body. One end of the roller shaft is provided with a gear. A lifting column corresponding to the gear is vertically and movably disposed at the bottom of the bottom ring of the fixture. The lifting column is provided with gear teeth that mesh with the gear. The lifting column is used to generate relative displacement with the bottom ring of the fixture when it exerts pressure on the bottom wall of the PEO treatment tank.

[0008] Preferably, the PEO treatment tank is provided with a cathode assembly, which includes an outer peripheral cathode component disposed around the inner cavity of the PEO treatment tank and an inner cathode component disposed between multiple outer peripheral cathode components and corresponding to the center of the fixture assembly.

[0009] Preferably, the inner circumference of the top of the clamp bottom ring is recessed downwards, and the recessed part is provided with a mounting groove; the bottom periphery of the clamp bottom ring is provided with a mounting cavity corresponding to the mounting groove; the roller shaft is rotatably disposed in the mounting groove, and the gear is located inside the mounting cavity; the lifting column is vertically movable in the mounting cavity, and initially the lower end of the lifting column protrudes from the bottom of the clamp bottom ring.

[0010] Preferably, the inner wall of the mounting cavity is provided with a guide post corresponding to the lifting column, and the lifting column is movably sleeved on the outside of the guide post.

[0011] Preferably, the top of the lifting column is provided with an elastic element for the lifting column to descend and reset.

[0012] Preferably, a one-way bearing is embedded at one end of the mounting groove cavity near the axis of the bottom ring of the fixture, and one end of the roller shaft is installed on the inner wall of the one-way bearing; a one-way bearing is installed at the other end of the roller shaft away from the axis of the bottom ring of the fixture, and a gear is installed outside the one-way bearing. The two one-way bearings are configured such that when the lifting column rises relative to the bottom ring of the fixture, the gear teeth on the lifting column can drive the support roller to rotate through the gear.

[0013] Preferably, the bottom of the mounting cavity is provided with a bottom cover, and the lower end of the lifting column extends downward through the bottom cover; the side wall of the lifting column is provided with a limiting flange located above the bottom cover and used to limit the movement of the lifting column.

[0014] Preferably, the elastic element is a compression spring, which is sleeved on the outside of the guide post.

[0015] Preferably, the lifting mechanism includes a lifting frame disposed at the top of the PEO treatment tank, a rotating shaft rotatably disposed on the lifting frame, a clamp top frame mounted at the bottom end of the rotating shaft, and a lifting power device for driving the lifting frame to rise and fall on the side of the PEO treatment tank.

[0016] Preferably, a worm gear is installed on the rotating shaft, a worm is rotatably mounted on the lifting frame and meshes with the worm gear, and a rotary power device for driving the worm to rotate is installed at one end of the lifting frame.

[0017] The technical effects and advantages of this invention are as follows:

[0018] In this invention, by setting peripheral and internal cathode components within the PEO treatment tank, both the outer peripheral and inner surfaces of cylindrical, tubular, and other hollow semiconductor cavity components are placed within a relatively effective electric field range. Simultaneously, a clamping assembly supports, holds, and conducts electricity to the workpiece. The workpiece's own weight drives the clamping head within the clamping assembly to press against the workpiece's sidewall, ensuring stable positioning of the workpiece during coating treatment and rotation. When the lifting mechanism lowers the clamping assembly, the orientation adjustment component triggers a pressure contact with the bottom of the PEO treatment tank. The support rollers rotate, simultaneously releasing the clamping head from the workpiece body, causing the workpiece body to rotate a certain angle relative to the clamping assembly. Subsequently, after the clamping assembly rises, the clamping head clamps the workpiece body again, thereby changing the position of the support point and clamping point on the workpiece body. As a result, areas that were originally blocked for a long time can be exposed to the electrolyte and micro-arc discharge environment in the subsequent coating stage, reducing the problems of local coating defects, thinness, and surface discontinuity caused by fixed clamping, and improving the integrity and circumferential consistency of the PEO ceramic coating on the inner and outer surfaces of hollow shell semiconductor cavity components. Attached Figure Description

[0019] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts:

[0020] Figure 1 This is a schematic diagram of the structure of the present invention;

[0021] Figure 2 This is a structural diagram of the lifting frame and PEO treatment tank of the present invention in a disassembled state;

[0022] Figure 3 This is a schematic diagram of the internal structure of the PEO treatment tank of the present invention;

[0023] Figure 4 This is a schematic diagram of the overall structure of the lifting frame and clamp assembly of the present invention;

[0024] Figure 5 This is a schematic diagram of the top frame and bottom ring of the clamp in the disassembled state.

[0025] Figure 6 This is a schematic diagram of the structure of the trigger base frame, supporting rollers, and fixture bottom ring of the present invention in a disassembled state;

[0026] Figure 7 For the present invention Figure 6 A structural diagram from the bottom perspective;

[0027] Figure 8 This is a cross-sectional structural diagram of the connection between the square tube and the inner sliding rod of the present invention.

[0028] Legend: 1. PEO treatment tank; 2. Lifting frame; 3. Lifting power unit; 4. Rotating shaft; 5. Rotation power unit; 6. Fixture top frame; 7. Fixture bottom ring; 8. Workpiece body; 9. Outer peripheral cathode component; 10. Internal cathode component; 11. Worm gear; 12. Worm wheel; 13. Square tube; 14. Inner slide rod; 15. Support roller; 16. Trigger base frame; 17. Mounting slot; 18. Bottom cover; 19. Roller shaft; 20. Gear; 21. Lifting column; 22. Guide column; 23. Elastic component; 24. Limiting flange; 25. Mounting cavity; 26. Elastic conductive plate; 27. Holding head. Detailed Implementation

[0029] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0030] like Figures 1-8As shown, this embodiment provides a PEO coating device for semiconductor cavity components, mainly used for plasma electrolytic oxidation treatment of cylindrical, tubular, or other hollow shell-shaped semiconductor cavity components. The device includes a PEO treatment tank 1, a workpiece body 8, a clamping assembly, and a lifting mechanism for driving the clamping assembly in and out of the PEO treatment tank 1. The PEO treatment tank 1 is used to hold PEO electrolyte. During processing, the workpiece body 8 is supported, held, and immersed in the electrolyte in the PEO treatment tank 1 by the clamping assembly. The workpiece body 8 acts as the anode and is connected to the positive electrode of the PEO power supply system, while the cathode assembly in the PEO treatment tank 1 is connected to the negative electrode of the PEO power supply system, thereby forming a micro-arc discharge environment on the surface of the workpiece body 8, causing an in-situ ceramic oxide coating to form on the surface of the workpiece body 8.

[0031] In this embodiment, the workpiece body 8 can be a cylindrical, tubular, hollow annular, or hollow shell-shaped metal component used in semiconductor etching cavities, deposition cavities, or other process chambers, such as cavity liners, annular liners, or cylindrical shielding components made of aluminum alloy or titanium alloy. This type of workpiece body 8 typically has an outer peripheral surface, an inner cavity surface, and end edges. During the PEO coating process, it is necessary not only to ensure that the workpiece body 8 can be stably immersed in the electrolyte, but also to ensure its reliable conductivity during the process, and to minimize the obstruction of coating formation caused by the fixed contact area between the fixture and the workpiece body 8.

[0032] The PEO treatment tank 1 is equipped with a cathode assembly, which includes peripheral cathodes 9 disposed around the inner cavity of the PEO treatment tank 1 and internal cathodes 10 disposed between multiple peripheral cathodes 9 and corresponding to the center of the fixture assembly. The peripheral cathodes 9 correspond to the outer peripheral surface of the workpiece body 8, and the internal cathodes 10 extend into or correspond to the inner cavity area of ​​the workpiece body 8. Multiple peripheral cathodes 9 can be spaced apart along the inner periphery of the PEO treatment tank 1, and internal cathodes 10 can be vertically arranged along the central area of ​​the fixture assembly so that after the workpiece body 8 enters the PEO treatment tank 1 with the fixture assembly, the internal cathodes 10 are located in the inner cavity of the workpiece body 8 or at a position corresponding to the inner cavity. Through the cooperation of the peripheral cathodes 9 and the internal cathodes 10, both the outer and inner sides of the cylindrical or tubular workpiece body 8 can be within a relatively effective electric field range, thereby improving the problem of insufficient discharge in the inner cavity area when only the outer cathode is used for treatment.

[0033] The lifting mechanism includes a lifting frame 2 located at the top of the PEO treatment tank 1. A rotating shaft 4 is rotatably mounted on the lifting frame 2. A clamping assembly is installed at the bottom of the rotating shaft 4. A lifting power device 3 for driving the lifting frame 2 to rise and fall is provided on the side of the PEO treatment tank 1. The lifting power device 3 can be a cylinder, hydraulic cylinder, linear motor, electric push rod, or other power device capable of providing linear lifting action. By driving the lifting frame 2 to rise and fall through the lifting power device 3, the rotating shaft 4 and the clamping assembly at its lower end can be driven to rise or fall as a whole, thereby allowing the workpiece body 8 to enter or leave the PEO treatment tank 1. Furthermore, when it is necessary to change the contact position of the workpiece body 8 relative to the clamping assembly, the lifting power device 3 can also drive the clamping assembly to continue to move downward, so that the lower part of the clamping assembly engages with the bottom wall of the PEO treatment tank 1 to trigger the action of the orientation adjustment component.

[0034] To achieve the slow rotation of the fixture assembly and the workpiece body 8, a worm gear 12 is installed on the rotating shaft 4, and a worm 11 meshing with the worm gear 12 is rotatably installed on the lifting frame 2. A rotary power device 5 for driving the worm 11 to rotate is installed at one end of the lifting frame 2. The rotary power device 5 can be a geared motor or other rotary drive device. When the rotary power device 5 is working, it drives the worm 11 to rotate. The worm 11 drives the rotating shaft 4 to rotate through the worm gear 12. The rotating shaft 4 further drives the fixture assembly and the workpiece body 8 to rotate slowly in the PEO treatment tank 1. The slow rotation of the workpiece body 8 allows it to be subjected to the cathodic electric field and electrolyte in different circumferential positions in sequence, reducing the circumferential differences caused by local discharge concentration, bubble retention, and fixed orientation treatment, which is beneficial to improving the uniformity and continuity of the circumferential coating of the workpiece body 8.

[0035] The fixture assembly includes a fixture top frame 6 bolted to the bottom of the rotating shaft 4. A fixture bottom ring 7 is provided below the fixture top frame 6 to support the workpiece body 8. The fixture top frame 6 can rise, fall and rotate synchronously with the rotating shaft 4. The fixture bottom ring 7 is used to support the bottom or end of the workpiece body 8. Inner slide rods 14 are symmetrically installed on opposite sides of the bottom of the fixture top frame 6. Square tubes 13 corresponding to the inner slide rods 14 are symmetrically arranged on opposite sides of the fixture bottom ring 7. The lower end of the inner slide rod 14 is movably connected to the inner side of the corresponding square tube 13, so that the fixture bottom ring 7 can generate a certain vertical relative displacement with respect to the fixture top frame 6. A limiting step, limiting pin, limiting groove or other limiting structure can be provided between the inner slide rod 14 and the square tube 13 to limit the relative displacement limit between the two, so that the fixture bottom ring 7 and the fixture top frame 6 can move relative to each other but cannot be separated, thus preventing the fixture assembly from disengaging during clamping, lifting, rotation or orientation adjustment.

[0036] The inner circumference of the top of the fixture bottom ring 7 is recessed downward to form a support area for accommodating and supporting the bottom of the workpiece body 8. The recessed part is provided with a mounting groove 17. A roller shaft 19 is rotatably mounted in the mounting groove 17. A support roller 15 for supporting the workpiece body 8 is provided on the roller shaft 19. The support roller 15 is located in the mounting groove 17 and can rotate relative to the fixture bottom ring 7. Multiple support rollers 15 can be provided. Multiple support rollers 15 are arranged at intervals along the circumference of the fixture bottom ring 7 so that after the workpiece body 8 is placed on the fixture bottom ring 7, its bottom or end can be supported by multiple support rollers 15. During the normal coating treatment stage, the support rollers 15 are used to support the workpiece body 8. During the orientation adjustment stage, they can rotate themselves to drive the workpiece body 8 to rotate a certain angle relative to the fixture assembly, thereby changing the area of ​​the workpiece body 8 that was originally in contact with the support rollers 15 or the holding head 27.

[0037] To drive the support roller 15 to rotate at a specific stage, the bottom periphery of the fixture bottom ring 7 is provided with a mounting cavity 25 corresponding to the mounting groove 17. One end of the roller shaft 19 extends into the mounting cavity 25, and a gear 20 is provided at the end of the roller shaft 19 located in the mounting cavity 25. A lifting column 21 corresponding to the gear 20 is vertically and movably arranged at the bottom of the fixture bottom ring 7. Specifically, the lifting column 21 is vertically and movably arranged in the mounting cavity 25. The lifting column 21 is provided with gear teeth that mesh with the gear 20. In the initial state, the lower end of the lifting column 21 protrudes from the bottom of the fixture bottom ring 7. When the lifting column 21 exerts pressure on the bottom wall of the PEO treatment tank 1 and moves upward relative to the fixture bottom ring 7, the gear teeth on the lifting column 21 can drive the gear 20 to rotate. The gear 20 further drives the support roller 15 to rotate through the roller shaft 19, so that the workpiece body 8 changes its orientation under the action of the support roller 15.

[0038] To enable multiple lifting columns 21 to rise and fall synchronously, a trigger base frame 16 is provided below the fixture bottom ring 7. The bottoms of multiple lifting columns 21 are connected to the trigger base frame 16. The trigger base frame 16 is used to trigger and press against the bottom wall of the PEO processing tank 1 when the fixture assembly continues to descend, so that multiple lifting columns 21 move synchronously relative to the fixture bottom ring 7 under the drive of the trigger base frame 16. By setting the trigger base frame 16, multiple support rollers 15 can participate in the orientation adjustment of the workpiece body 8 more consistently, avoiding the workpiece body 8 from tilting, shifting or rotating unstable due to the force exerted by a single lifting column 21.

[0039] The inner wall of the mounting cavity 25 is provided with a guide post 22 corresponding to the lifting column 21. The lifting column 21 is movably sleeved on the outside of the guide post 22. The guide post 22 is used to guide the lifting movement of the lifting column 21, increase the stability of the lifting column 21 when it moves up and down, and enable the gear teeth on the lifting column 21 to maintain stable meshing with the gear 20. The top of the lifting column 21 is provided with an elastic element 23 for the lifting column 21 to descend and reset. The elastic element 23 is preferably a compression spring. The compression spring is sleeved on the outside of the guide post 22 to simultaneously fix and guide the elastic element 23. With the setting of the elastic element 23, when the trigger base 16 is released from the pressure of the bottom wall of the PEO treatment tank 1, the lifting column 21 can be reset downward under the elastic force of the elastic element 23, so that the lower end of the lifting column 21 protrudes out of the bottom of the clamp bottom ring 7 again, which is convenient for subsequent triggering and engagement with the bottom wall of the PEO treatment tank 1.

[0040] The bottom of the mounting cavity 25 is provided with a bottom cover 18. The lower end of the lifting column 21 extends downward through the bottom cover 18. The bottom cover 18 is used to seal the bottom of the mounting cavity 25 and to guide the lower end of the lifting column 21 to extend and move up and down. The side wall of the lifting column 21 is provided with a limiting flange 24 located above the bottom cover 18 and used to limit the movement of the lifting column 21. The limiting flange 24 can cooperate with the bottom cover 18 when the lifting column 21 is reset downward to prevent the lifting column 21 from detaching from the mounting cavity 25, thereby ensuring that the movement range of the lifting column 21 in the mounting cavity 25 is stable and controllable.

[0041] To prevent the supporting roller 15 from rotating in the opposite direction when the lifting column 21 is reset, a one-way bearing is embedded at one end of the inner cavity of the mounting groove 17 near the axis of the clamp bottom ring 7, and one end of the roller shaft 19 is installed on the inner wall of the one-way bearing; a one-way bearing is installed at the other end of the roller shaft 19 away from the axis of the clamp bottom ring 7, and the gear 20 is installed on the outside of the one-way bearing. The two one-way bearings are configured such that when the lifting column 21 rises relative to the bottom ring 7 of the fixture, the gear teeth on the lifting column 21 can drive the support roller 15 to rotate through the gear 20; when the lifting column 21 is reset downward under the action of the elastic element 23, the one-way bearing at the end of the roller shaft 19 near the axis of the bottom ring 7 of the fixture is in a restricted state, and the one-way bearing at the gear 20 is in an overrunning state, so that the gear 20 and the roller shaft 19 rotate relative to each other, and the support roller 15 remains stationary, thereby preventing the support roller 15 from rotating in the opposite direction as the lifting column 21 is reset; through this one-way transmission relationship, the support roller 15 can be rotated at a certain angle in a predetermined direction each time it is triggered, thereby driving the workpiece body 8 to gradually change its circumferential position relative to the fixture assembly.

[0042] An elastic conductive plate 26 is installed on the side of the square tube 13 near the workpiece body 8. A holding head 27 for pressing against the side wall of the workpiece body 8 is installed at the lower end of the elastic conductive plate 26 near the axis of the clamp bottom ring 7. The holding head 27 can also be a conductive metal part to achieve conductive contact while pressing against the workpiece body 8. The side of the elastic conductive plate 26 near the inner slide rod 14 cooperates with the inclined surface of the inner slide rod 14, forming a wedge structure. When the workpiece body 8 is placed on the clamp bottom ring 7, the weight of the workpiece body 8 acts on the supporting roller 15 and the clamp bottom ring 7, making the clamp bottom ring 7 and the square tube 13 as a whole... When the inner slide bar 14 moves downward, as the square tube 13 moves downward relative to the inner slide bar 14, the inclined surface of the inner slide bar 14 acts on the elastic conductive plate 26, causing the elastic conductive plate 26 to bend towards the side wall of the workpiece body 8 under pressure, thereby driving the clamping head 27 to press against the side wall of the workpiece body 8. Thus, the clamping assembly can utilize the self-weight of the workpiece body 8 and achieve adaptive clamping through the wedge engagement between the inner slide bar 14 and the elastic conductive plate 26, without the need for an additional independent lateral clamping power source, so that the workpiece body 8 can maintain a stable engagement with the clamping assembly during coating treatment and rotation.

[0043] During the orientation adjustment stage, when the lifting mechanism drives the clamp assembly to continue moving downward, causing the trigger base 16 to press against the bottom wall of the PEO treatment tank 1, the bottom wall of the PEO treatment tank 1 generates an upward reaction force on the trigger base 16 and the clamp bottom ring 7, causing the clamp bottom ring 7 and the square tube 13 to move upward relative to the inner slide rod 14. At this time, the wedge clamping effect between the elastic conductive plate 26 and the inner slide rod 14 weakens, and the elastic conductive plate 26 drives the holding head 27 to reset or rebound away from the side wall of the workpiece body 8, so that the holding head 27 releases or reduces its resistance to the workpiece body 8. Simultaneously, the trigger base 16 drives multiple lifting columns 21 to rise. The lifting columns 21 compress the elastic element 23 and drive the gear 20 to rotate through the gear teeth on it. The gear 20 drives the support roller 15 to rotate through the roller shaft 19. Since the holding head 27 has released or reduced the grip on the workpiece body 8 at this time, the support roller 15 can drive the workpiece body 8 to rotate relative to the fixture assembly by a certain range, so that the area of ​​the workpiece body 8 that was originally covered by the holding head 27 or the support roller 15 is transferred to the exposed position, so that it can continue to participate in the electrolyte contact and micro-arc discharge reaction in the subsequent coating stage.

[0044] After the orientation adjustment is completed, the lifting mechanism drives the clamp assembly to rise, triggering the base frame 16 to gradually separate from the bottom wall of the PEO treatment tank 1. The elastic element 23 drives the lifting column 21 to descend and reset. Since there is a one-way transmission relationship between the gear 20 and the roller shaft 19, the gear 20 will not drive the support roller 15 to rotate in the opposite direction during the descent and reset process of the lifting column 21, so that the workpiece body 8 maintains the adjusted orientation. As the trigger base frame 16 is released from pressure, the workpiece body 8 once again relies on its own weight to make the clamp bottom ring 7 and the square tube 13 move down relative to the inner slide rod 14. The elastic conductive plate 26 bends towards the side wall of the workpiece body 8 again under the action of the wedge, and the holding head 27 presses against the side wall of the workpiece body 8 again. Thus, the workpiece body 8 can be held and connected again in the new circumferential position and continue to perform subsequent PEO coating treatment.

[0045] In this embodiment, the elastic conductive plate 26 and the holding head 27 can be made of conductive metal material. The inner slide rod 14, square tube 13, fixture top frame 6, and rotating shaft 4 can all be made of conductive metal material or at least have conductive connection structures on the conductive path. An electric slip ring can be provided at the upper end of the rotating shaft 4. The fixed end of the electric slip ring is connected to the positive terminal of the PEO power supply system, and the rotating end of the electric slip ring is electrically connected to the rotating shaft 4 or the fixture assembly, so that the positive terminal of the PEO power supply system can be transmitted to the workpiece body 8 through the electric slip ring, rotating shaft 4, fixture top frame 6, inner slide rod 14, square tube 13, elastic conductive plate 26, and holding head 27. In other embodiments, the elastic conductive plate 26 can also be connected with a wire, which extends into the rotating shaft 4 and is connected to the rotating shaft 4 or the electric slip ring through the wire to ensure reliable conduction between the elastic conductive plate 26, the holding head 27, and the workpiece body 8. Through the above conductive structure, the holding head 27 can both laterally press against the workpiece body 8 and act as an anode conductive part in contact with the workpiece body 8.

[0046] The support roller 15 can be made of insulating material, or an insulating layer can be provided on the outer periphery of the support roller 15 to reduce the impact of the support roller 15 on the conductivity and coating formation process of the workpiece body 8 when it comes into contact with the workpiece body 8. The elastic conductive plate 26 and the holding head 27 mainly undertake the functions of conductivity and lateral holding, while the support roller 15 mainly undertakes the functions of support and orientation adjustment. By dividing the functions of support, holding and conductivity, and changing the contact position of the workpiece body 8 relative to the support roller 15 and the holding head 27 through the orientation adjustment component, the problems of coating loss, thin thickness or poor surface continuity caused by long-term obstruction of the fixed contact area can be reduced.

[0047] It should be noted that the present invention may also include a PEO power supply system, an electric slip ring, an electrolyte circulation and filtration system, a temperature control system, and other necessary structures or devices related to the PEO treatment process. The PEO power supply system is used to provide the pulse power required for PEO treatment to the workpiece body 8 and the cathode assembly; the electrolyte circulation and filtration system is used to maintain the circulation, filtration, and cleanliness of the electrolyte in the PEO treatment tank 1; and the temperature control system is used to regulate the electrolyte temperature. For structural parts that are close to the electrolyte and do not need to participate in conductivity, an insulating layer, insulating sleeve, insulating pad, or insulating isolation component resistant to electrolyte corrosion can be provided to reduce the participation of unnecessary metal parts in discharge or interference with the coating formation of the workpiece body 8.

[0048] Through the above structure, this embodiment can achieve adaptive holding by utilizing the self-weight of the workpiece body 8 in conjunction with the wedge action of the inner slide bar 14 and the elastic conductive plate 26, so that the workpiece body 8 remains stable during PEO coating treatment and slow rotation. At the same time, by utilizing the continued downward movement of the lifting mechanism, the trigger base 16 is pressed against the bottom wall of the PEO treatment tank 1, and the unidirectional transmission relationship between the lifting column 21, gear 20, roller shaft 19 and support roller 15 drives the workpiece body 8 to change its circumferential position. Compared with the fixed clamping method, this embodiment can make the support point, clamping point and conductive contact point of the workpiece body 8 change at different coating stages, so that the area originally blocked by the clamp is exposed to the electrolyte and micro-arc discharge environment in the subsequent stages, thereby reducing the problems of local coating defects, thin thickness and surface discontinuity, and improving the integrity, circumferential consistency and overall processing quality of PEO ceramic coating of hollow shell semiconductor cavity components such as cylindrical and tubular shapes.

[0049] The detailed working process of this invention is as follows:

[0050] In use, the lifting power device 3 first raises the lifting frame 2, so that the clamping assembly is located above the PEO processing tank 1 or in a position that is convenient for clamping the workpiece body 8. The workpiece body 8 is placed in the upper recessed area of ​​the clamping bottom ring 7. The bottom of the workpiece body 8 is supported by multiple support rollers 15. Due to the weight of the workpiece body 8, the clamping bottom ring 7 and the square tube 13 move downward relative to the clamping top frame 6 and the inner slide rod 14. The inclined surface of the inner slide rod 14 cooperates with the elastic conductive plate 26, so that the elastic conductive plate 26 bends towards the side wall of the workpiece body 8. The holding head 27 presses against the side wall of the workpiece body 8, so that the workpiece body 8 is stably held on the clamping assembly. At this time, the holding head 27 can also serve as a conductive contact part, so that the workpiece body 8 is connected to the positive terminal of the PEO power supply system.

[0051] After clamping is completed, the lifting power device 3 drives the lifting frame 2 to descend. The lifting frame 2 drives the clamping assembly and the workpiece body 8 into the PEO treatment tank 1 through the rotating shaft 4, so that the workpiece body 8 is immersed in the electrolyte. At this time, the outer peripheral cathode 9 is located on the outer periphery of the workpiece body 8, and the inner cathode 10 is located in the inner cavity area of ​​the workpiece body 8. After the PEO power supply system is started, the workpiece body 8 acts as the anode, and the outer peripheral cathode 9 and the inner cathode 10 act as the cathode, forming a PEO coating treatment environment in the electrolyte. During the treatment process, the rotating power device 5 can drive the worm gear 11 to rotate. The worm gear 11 drives the rotating shaft 4 and the clamping assembly to rotate slowly through the worm wheel 12, so that the workpiece body 8 rotates slowly in the electrolyte with the clamping assembly, thereby improving the electric field effect and electrolyte uniformity in the circumferential position of the workpiece body 8.

[0052] After a period of coating treatment, the output of the rotary power device 5 can be stopped or reduced, and the lifting power device 3 can drive the clamp assembly to continue to move downward, so that the trigger base 16 presses against the bottom wall of the PEO treatment tank 1. Due to the reaction force of the bottom wall of the PEO treatment tank 1 on the trigger base 16, the trigger base 16 drives multiple lifting columns 21 to move upward relative to the clamp bottom ring 7. At the same time, after the clamp bottom ring 7 is subjected to the upward reaction force, it tends to move upward relative to the inner slide rod 14. The wedge clamping effect between the elastic conductive plate 26 and the inner slide rod 14 is weakened, and the holding head 27 releases or reduces the clamping on the side wall of the workpiece body 8, so that the workpiece body 8 can rotate relative to the clamp assembly under the drive of the support roller 15.

[0053] As the lifting column 21 rises relative to the bottom ring 7 of the clamp, the teeth on the lifting column 21 mesh with the gear 20 and drive the gear 20 to rotate. The gear 20 drives the support roller 15 to rotate in a predetermined direction through the one-way bearing and the roller shaft 19. Since the clamping effect of the holding head 27 on the workpiece body 8 is released or weakened at this time, the support roller 15 can drive the workpiece body 8 to rotate relative to the clamp assembly by a certain angle, thereby changing the contact position between the workpiece body 8 and the support roller 15 and the holding head 27. In this way, the area that was originally blocked by the support roller 15 or the holding head 27 can be exposed in the subsequent coating process and participate in the electrolyte contact and micro-arc discharge reaction.

[0054] After the orientation adjustment is completed, the lifting power unit 3 drives the lifting frame 2 and the clamping assembly to rise, so that the trigger base 16 gradually separates from the bottom wall of the PEO treatment tank 1. After the trigger base 16 is released from pressure, the elastic element 23 drives the lifting column 21 to reset downward. During the reset process of the lifting column 21, since there is a one-way bearing between the gear 20 and the roller shaft 19, the reset movement of the lifting column 21 will not cause the support roller 15 to rotate in the opposite direction. The support roller 15 and the workpiece body 8 can maintain the adjusted orientation. As the clamping bottom ring 7 moves down relative to the inner slide rod 14 under the weight of the workpiece body 8, the elastic conductive plate 26 bends again under the action of the wedge, and the holding head 27 presses against the side wall of the workpiece body 8 again, so that the workpiece body 8 is stably held and connected in the new circumferential position. After that, the equipment can continue to carry out the next stage of PEO coating treatment.

[0055] Through the above process, the present invention can, without completely removing the workpiece body 8 from the PEO processing tank 1, use the downward movement of the lifting mechanism as a trigger for the orientation adjustment component, so that the support roller 15 drives the workpiece body 8 to change its circumferential position relative to the clamping assembly, and simultaneously release and re-form the gripping head 27 on the workpiece body 8. Compared with the fixed clamping method, the present invention can change the support point, clamping point and conductive contact point of the workpiece body 8 at different coating stages, so that the area originally blocked by the clamping contact is exposed to the electrolyte and discharge environment in the subsequent stages, thereby reducing the problems of local coating defects, thin thickness or surface discontinuity, and improving the integrity, circumferential consistency and overall processing quality of PEO ceramic coating of hollow shell semiconductor cavity components such as cylindrical and tubular shapes.

[0056] Furthermore, the cooperation between the outer peripheral cathode 9 and the inner cathode 10 can improve the electric field coverage of the inner and outer surfaces of the workpiece body 8, and the slow rotation of the clamping assembly can further reduce the processing differences of different circumferential positions of the workpiece body 8; the orientation adjustment assembly realizes the staged repositioning of the workpiece body 8 through the unidirectional transmission relationship between the lifting column 21, gear 20, roller shaft 19 and support roller 15, which is compact and reliable in operation; the cooperation of the elastic element 23, guide column 22, bottom cover 18 and limiting flange 24 ensures that the lifting column 21 can be stably guided and reset, thereby facilitating the orientation adjustment assembly to perform multiple cyclic operations.

[0057] It should be noted that the PEO power supply system, electrolyte circulation filtration system, temperature control system, rotating conductive structure, and related insulation protection structure can be conventionally configured according to the PEO coating process requirements. For example, the rotating conductive structure can use an electric slip ring or other rotating conductive parts. The fixed end of the electric slip ring is connected to the positive terminal of the PEO power supply system, and the rotating end of the electric slip ring is electrically connected to the rotating shaft 4 or the clamp assembly. The outer peripheral cathode 9 and the inner cathode 10 in the PEO treatment tank 1 can be connected to the negative terminal of the PEO power supply system through the cathode conductive parts. For structural locations that require insulation protection, an insulating layer, insulating sleeve, or insulating pad resistant to electrolyte corrosion can be installed to reduce unnecessary metal parts from participating in the discharge or interfering with the coating formation of the workpiece body 8.

[0058] The above are merely preferred embodiments of the present invention and do not limit the scope of protection of the present invention. Any conventional adjustments made by those skilled in the art based on the technical concept disclosed in the present invention to the structural form, driving method, material selection, or number of components, as long as they still utilize the clamping assembly to hold the workpiece body 8, utilize the orientation adjustment assembly to change the contact position between the workpiece body 8 and the clamping assembly, and are used to improve the problem of uneven local coating caused by clamp obstruction during PEO coating treatment, should fall within the scope of protection of the present invention.

Claims

1. A PEO coating apparatus for semiconductor chamber components, characterized in that, It includes a PEO processing tank (1), a workpiece body (8), a fixture assembly, and a lifting mechanism for driving the fixture assembly in and out of the PEO processing tank (1); The fixture assembly includes a fixture top frame (6) driven to lift by a lifting mechanism. A fixture bottom ring (7) is provided below the fixture top frame (6) for supporting the workpiece body (8). An inner slide rod (14) is installed on the fixture top frame (6). A square tube (13) corresponding to the inner slide rod (14) is provided on the fixture bottom ring (7). The lower end of the inner slide rod (14) is movably connected to the inside of the square tube (13). An elastic conductive plate (26) is installed on the side of the square tube (13) near the workpiece body (8). A holding head (27) for pressing against the side wall of the workpiece body (8) is installed on the elastic conductive plate (26). The side of the elastic conductive plate (26) near the inner slide rod (14) is engaged with the inclined surface of the inner slide rod (14). When the square tube (13) moves down relative to the inner slide rod (14), the elastic conductive plate (26) is pressed and bends outward. It also includes an orientation adjustment component, which includes a roller shaft (19) rotatably disposed in the bottom ring (7) of the fixture. The roller shaft (19) is provided with a support roller (15) for supporting the workpiece body (8). A gear (20) is provided at one end of the roller shaft (19). A lifting column (21) corresponding to the gear (20) is vertically and movably disposed at the bottom of the bottom ring (7). The lifting column (21) is provided with gear teeth that mesh with the gear (20). The lifting column (21) is used to generate pressure with the bottom wall of the PEO treatment tank (1) and to cause relative displacement with the bottom ring (7).

2. The PEO coating apparatus for semiconductor chamber components according to claim 1, characterized in that: The PEO processing tank (1) is provided with a cathode assembly, which includes an outer peripheral cathode component (9) disposed around the inner cavity of the PEO processing tank (1) and an inner cathode component (10) disposed in the middle of the multiple outer peripheral cathode components (9) and corresponding to the center of the fixture assembly.

3. The PEO coating apparatus for semiconductor chamber components according to claim 1, characterized in that: The inner circumference of the top of the clamp bottom ring (7) is recessed downwards, and the recessed part is provided with a mounting groove (17); the bottom periphery of the clamp bottom ring (7) is provided with a mounting cavity (25) corresponding to the mounting groove (17); the roller shaft (19) is rotatably disposed in the mounting groove (17), and the gear (20) is located inside the mounting cavity (25); the lifting column (21) is vertically and movably disposed in the mounting cavity (25), and initially the lower end of the lifting column (21) protrudes from the bottom of the clamp bottom ring (7).

4. The PEO coating apparatus for semiconductor chamber components according to claim 3, characterized in that: The inner wall of the mounting cavity (25) is provided with a guide post (22) corresponding to the lifting column (21), and the lifting column (21) is movably sleeved on the outside of the guide post (22).

5. The PEO coating apparatus for semiconductor chamber components according to claim 4, characterized in that: The top of the lifting column (21) is provided with an elastic element (23) for the lifting column (21) to descend and reset.

6. The PEO coating apparatus for semiconductor chamber components according to claim 5, characterized in that: One-way bearing is embedded at one end of the inner cavity of the mounting groove (17) near the axis of the clamp bottom ring (7), and one end of the roller shaft (19) is installed on the inner wall of the one-way bearing; one-way bearing is installed at the end of the roller shaft (19) away from the axis of the clamp bottom ring (7), and the gear (20) is installed outside the one-way bearing. The two one-way bearings are configured such that when the lifting column (21) rises relative to the clamp bottom ring (7), the gear teeth on the lifting column (21) can drive the support roller (15) to rotate through the gear (20).

7. The PEO coating apparatus for semiconductor chamber components according to claim 5, characterized in that: The bottom of the mounting cavity (25) is provided with a bottom cover (18), and the lower end of the lifting column (21) extends downward through the bottom cover (18); the side wall of the lifting column (21) is provided with a limiting flange (24) located above the bottom cover (18) and used to limit the lifting column (21).

8. The PEO coating apparatus for semiconductor chamber components according to claim 5, characterized in that: The elastic element (23) is a compression spring, which is sleeved on the outside of the guide post (22).

9. The PEO coating apparatus for semiconductor chamber components according to any one of claims 1-8, characterized in that: The lifting mechanism includes a lifting frame (2) set at the top of the PEO treatment tank (1), a rotating shaft (4) is rotatably set on the lifting frame (2), a clamp top frame (6) is installed at the bottom of the rotating shaft (4), and a lifting power device (3) for driving the lifting frame (2) to lift is set on the side of the PEO treatment tank (1).

10. The PEO coating apparatus for semiconductor chamber components according to claim 9, characterized in that: A worm gear (12) is installed on the rotating shaft (4), and a worm (11) that meshes with the worm gear (12) is rotatably installed on the lifting frame (2). A rotary power device (5) for driving the worm (11) to rotate is installed at one end of the lifting frame (2).

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