Electrostatic elimination process for high vacuum equipment

Abstract

This invention discloses an electrostatic elimination process for high-vacuum equipment, relating to the semiconductor manufacturing field. Step 1 involves adsorption of a semiconductor substrate. Step 2 involves flexible substrate holding. During negative pressure suction, the negative pressure pulls the three tarpaulins of the pressing assembly downwards, causing flexible deformation. This causes the movable plates on both sides to move downwards and compress the springs. The sealing folding plate adapts to deformation to maintain the chamber seal. The movable plates move the L-shaped pressure plate towards the upper surface of the placement platform, achieving flexible holding of the substrate through anti-static insulating pads. Step 3 involves electrostatic elimination of the substrate. An external ion source is activated, and the plasma gas generated by the ion source is delivered to the blowing pipe through a hose and blown onto the substrate surface through a nozzle. This invention enables the negative pressure generated during adsorption to automatically pull the tarpaulins downwards, causing the anti-static insulating pads to flexibly hold the substrate edges, evenly dispersing the holding force and avoiding physical damage to the substrate caused by localized stress concentration.

Description

Technical Field

[0001] This invention relates primarily to the field of semiconductor manufacturing technology, specifically to an electrostatic elimination process for high-vacuum equipment. Background Technology

[0002] In the manufacturing process of precision devices such as semiconductors, the substrate mounting process usually needs to be carried out in a high vacuum environment. This strict requirement is mainly to remove suspended particles, dust, water vapor and other impurities in the air, and to prevent them from adhering to the substrate surface or entering the material interface during the mounting process. At the same time, static electricity is also easily generated on the surface of the workpiece. The presence of static electricity can not only cause device breakdown, but may also lead to a decrease in equipment accuracy and seriously affect product yield.

[0003] The placement platform and mounting equipment described in the prior art include a stage and a pressure block disposed on the stage. The stage is provided with an adsorption hole and an air blowing hole. The adsorption hole is used to communicate with a vacuum hole on the mounting machine stage to adsorb the substrate. The pressure block is provided with a first air hole and a second air hole that are interconnected. The first air hole is used to communicate with an ion air hole on the mounting machine stage, and the second air hole is used to blow ion gas onto the substrate.

[0004] While the aforementioned technologies can eliminate static electricity around the chips on the substrate, the pressure plate employs a rigid, fixed structural design. Although this structure possesses a certain degree of stability, it is difficult to adaptively adjust to subtle differences between different substrates in practical applications. Due to its inability to flexibly adapt to variations in substrate curvature, thickness, or surface unevenness, localized stress concentration can easily occur on the substrate during the pressing process, leading to microcracks, deformation, or other physical damage. This, in turn, affects the yield and reliability of the final product. Furthermore, this technology has certain limitations in controlling the purging range of plasma gas, resulting in insufficient uniformity of airflow distribution and difficulty in achieving precise coverage of the entire processing area. Summary of the Invention

[0005] Therefore, the purpose of this invention is to provide an electrostatic elimination process for high vacuum equipment to solve the technical problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An electrostatic elimination process for a high vacuum device includes the following steps: Step 1: Semiconductor substrate adsorption. The vacuum chamber is evacuated to a preset high vacuum level. The substrate is transported through the inlet to the upper surface of the placement platform via a vacuum isolation and transmission structure, so that the substrate is accurately placed above the adsorption hole and between the two L-shaped pressure plates at the preset position, thus completing the initial positioning of the substrate. Start the suction pump. The suction pump uses the suction tube to perform negative pressure suction on the built-in chamber of the placement platform, so that the chamber and the top suction hole generate a continuous negative pressure suction force, forming a vacuum adsorption on the lower surface of the substrate. Step 2: Flexible pressing of the substrate. During the negative pressure suction process, the negative pressure will pull the three tarpaulins of the pressing component downward to undergo flexible deformation, and drive the movable plates on both sides to move down and squeeze the compression spring. The sealing folding plate adapts to deformation to maintain the chamber seal. The movable plate moves the L-shaped pressure plate closer to the upper surface of the platform. The anti-static insulating pads provide flexible pressure to the substrate. Under the action of their own gravity, the air pipe and the moving blocks on both sides cause the telescopic rod to stretch naturally. The adaptive adjustment ensures that the moving blocks are always tightly connected to the slide rail on the L-shaped pressure plate. Step 3: Static elimination on the substrate. The external ion source is activated, and the plasma gas generated by the ion source is delivered to the blowing pipe through the hose and blown onto the substrate surface through the nozzle. At the same time, the drive motor outside the vacuum chamber drives two lead screws to rotate synchronously through the gears and gear chains in the drive box, controlling the moving block to slide back and forth and drive the blowing pipe to move horizontally, so as to realize the full-area plasma gas blowing of the substrate to eliminate static electricity.

[0007] Specifically, the vacuum chamber has an inlet and an outlet on its two side walls, and the placement platform is fixed in the vacuum chamber by a mounting base at the bottom. The placement platform has a cavity inside, and the upper surface of the placement platform has several adsorption holes that communicate with the cavity. The bottom of the placement platform is fixed in the mounting base with an adsorption tube that communicates with the cavity. The adsorption tube passes through the vacuum chamber and is connected to an external suction pump through a pipe. The pressing assembly is disposed within the chamber. The two L-shaped pressure plates are symmetrically arranged above the long side of the placement platform. The outer wall of the long side of the placement platform is provided with a square through groove communicating with the chamber. The vertical plates of the two L-shaped pressure plates are connected to the pressing assembly passing through the square through groove. The blowing pipe is horizontally disposed above the two L-shaped pressure plates. Movable blocks are fixed at both ends of the blowing pipe. The vacuum chamber is provided with a lead screw above the two movable blocks. Moving blocks are installed on the two lead screws. The lower surfaces of the two moving blocks are connected to the moving blocks through telescopic rods. The two moving blocks are slidably connected to the upper surface of the corresponding L-shaped pressure plates.

[0008] Specifically, the pressing assembly includes three tarpaulins and two movable plates. The three tarpaulins are evenly distributed between the two movable plates, and each of the three tarpaulins is fixed to the wall screws of the two movable plates. Each of the two movable plates has a horizontal through-slot. The top and bottom of each of the two square through-slots are fixed with sealing folding plates. The end of each sealing folding plate is fixedly connected to the surface of the movable plate. The side of each of the two movable plates extending out of the square through-slot is fixedly connected to the vertical surface of the corresponding L-shaped pressure plate.

[0009] Specifically, in this technical solution, multiple guide rods are provided on both sides of the interior of the chamber. The two movable plates are slidably sleeved on the multiple guide rods on one side of the chamber. The two ends of the multiple guide rods are fixedly connected to the top wall and bottom wall of the chamber, respectively. Three compression springs are fixed on the lower surface of the two movable plates, and the bottom end of each compression spring is fixedly connected to the bottom wall of the chamber.

[0010] Specifically, in this technical solution, antistatic insulating pads are adhered to the side of the two L-shaped pressure plates near the upper surface of the placement platform. The sealing folding plate is made of flexible high-vacuum sealing material, and the gap between it and the side wall of the square through groove is filled with sealing gaskets.

[0011] Specifically, in this technical solution, the bottom ends of the two moving blocks are provided with sliding grooves, the upper surfaces of the two L-shaped pressure plates are fixed with slide rails, the groove walls of the two sliding grooves are embedded with balls, and the two sliding grooves are slidably connected to the slide rails through the embedded balls.

[0012] Specifically, in this technical solution, both ends of the two lead screws are fixed with rotating shafts via flanges, and the end of each rotating shaft is rotatably connected to the inner wall of the vacuum chamber. The outer wall of the vacuum chamber is located above the inlet and is fitted with a drive box via screws. The drive box contains a chain drive and is mounted on two rotating shafts that pass through the vacuum chamber. The outer wall of the drive box is fitted with a drive motor via bolts, and the output end of the drive motor is connected to a rotating shaft via a coupling.

[0013] Specifically, in this technical solution, a magnetohydrodynamic seal is installed at the point where the rotating shaft passes through the wall of the vacuum chamber. Flexible sealing covers are provided on both sides of the two moving blocks facing the rotating shaft. Each flexible sealing cover has a mounting plate fixed at both ends. One end of the mounting plate of each flexible sealing cover is sealed and welded to the outer wall of the moving block, and the other end of the mounting plate of each flexible sealing cover is sealed and welded to the inner wall of the vacuum chamber. Each flexible sealing cover is sleeved on the lead screw and the rotating shaft.

[0014] Specifically, in this technical solution, the ends of both telescopic rods are fixed to the bottom of the moving block with screws, and the telescopic ends of both telescopic rods are fixedly connected to the top of the moving block with screws. Specifically, in this technical solution, multiple nozzles are evenly arranged on the lower surface of the air blowing pipe, and one end of the air blowing pipe is connected to a flexible tube. The flexible tube passes through the corresponding moving block and the mounting base and is connected to the ion source outside the vacuum room.

[0015] In summary, the present invention has the following advantages: through the linkage design of the negative pressure driven pressing component and the L-shaped pressure plate, the negative pressure generated during the adsorption process automatically pulls the tarpaulin to deform and press down, which drives the antistatic insulating soft pad to flexibly press the edge of the substrate, evenly disperses the pressing force, and avoids physical damage to the substrate caused by local stress concentration. In addition, combined with the reciprocating full-area scanning of the plasma blowing tube, complete coverage and uniformity of static elimination in a high vacuum environment are achieved, which significantly improves the product yield. The linkage mechanism of negative pressure suction and pressing action eliminates the independent pressure plate drive device. The pressing action is completed by the vacuuming process itself, which simplifies the equipment structure and can simultaneously shorten the operation cycle of substrate positioning and fixing, improve the overall processing efficiency of high vacuum mounting process. At the same time, the multiple sealing structure of the chamber and vacuum chamber can adapt to deformation as the component slides, and always maintain a high vacuum sealing state. Furthermore, relying on the self-weight adaptive tension design of the telescopic rod and the sliding cooperation structure of the ball slide rail, it can ensure that the blowing component always maintains a stable connection and sliding relationship with the holding structure, eliminating problems such as jamming and derailment of the blowing pipe during movement. Attached Figure Description

[0016] Figure 1 This is a process flow diagram of the present invention; Figure 2 This is a schematic diagram of the vacuum chamber of the present invention; Figure 3 This is a schematic diagram of the cross-sectional structure of the vacuum chamber of the present invention; Figure 4 This is a schematic diagram of the placement platform and air blowing pipe structure of the present invention; Figure 5 This is a cross-sectional orthogonal axonometric structural diagram of the placement platform of the present invention; Figure 6 This is a cross-sectional oblique axonometric structural schematic diagram of the placement platform of the present invention; Figure 7 This is a schematic diagram of the lead screw, air blowing pipe, and L-shaped pressure plate structure of the present invention. Figure 8 For the present invention Figure 7 Enlarged view of point A in the middle.

[0017] Figure Descriptions: 1. Vacuum chamber; 101. Inlet; 102. Outlet; 103. Drive box; 1031. Drive motor; 2. Placement platform; 201. Chamber; 202. Adsorption hole; 203. Square through groove; 204. Mounting base; 2041. Adsorption tube; 3. L-shaped pressure plate; 301. Antistatic insulating pad; 302. Slide rail; 4. Downward pressure assembly; 401. Canopy; 402. Guide rod; 403. Movable plate; 404. Compression spring; 405. Sealing folding plate; 5. Air blowing pipe; 501. Nozzle; 502. Hose; 6. Lead screw; 601. Rotating shaft; 602. Moving block; 603. Telescopic rod; 604. Moving block; 6041. Slide groove; 605. Flexible sealing cover. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0019] The embodiments of the present invention will now be described.

[0020] In this embodiment, please refer to Figure 1 - Figure 8 As shown, an electrostatic elimination process for a high vacuum device includes the following steps: Step 1: Adsorption of semiconductor substrate. Vacuum chamber 1 is evacuated to a preset high vacuum level. The substrate is transported to the upper surface of the placement platform 2 through the inlet 101 via the vacuum isolation and transmission structure, so that the substrate is accurately placed above the adsorption hole 202 and between the two L-shaped pressure plates 3 at the preset position, thus completing the initial positioning of the substrate. Start the suction pump. The suction pump uses the suction tube 2041 to perform negative pressure suction on the built-in chamber 201 of the placement platform 2, so that the chamber 201 and the top suction hole 202 generate a continuous negative pressure suction force, forming a vacuum adsorption on the lower surface of the substrate. Step 2: Flexible pressing of the substrate. During the negative pressure suction process, the negative pressure will pull the three tarpaulin 401 of the pressing component 4 downward to undergo flexible deformation, and drive the movable plates 403 on both sides to move down and squeeze the compression spring 404. The sealing folding plate 405 adapts to deformation to keep the chamber 201 sealed. The movable plate 403 drives the L-shaped pressure plate 3 to move closer to the upper surface of the placement platform 2. The anti-static insulating soft pad 301 achieves flexible pressing of the substrate. Under the action of its own gravity, the air pipe 5 and the moving blocks 604 on both sides cause the telescopic rod 603 to stretch naturally. The adaptive adjustment can ensure that the moving block 604 is always tightly connected to the slide rail 302 on the L-shaped pressure plate 3. Step 3: Static elimination on the substrate. The external ion source is activated, and the plasma gas generated by the ion source is delivered to the blowing pipe 5 through the hose 502 and blown onto the substrate surface through the nozzle 501. At the same time, the drive motor 1031 outside the vacuum chamber 1 drives the two lead screws 6 to rotate synchronously through the gears and gear chains in the drive box 103, controlling the moving block 602 to slide back and forth and drive the blowing pipe 5 to move horizontally, so as to realize the full-area plasma gas blowing of the substrate to eliminate static electricity.

[0021] Please see Figure 2 - Figure 8 As shown, the vacuum chamber 1 has an inlet 101 and an outlet 102 on its two side walls, respectively. Both the inlet 101 and the outlet 102 are externally connected to a vacuum isolation transmission structure, which can maintain a stable high vacuum environment inside the vacuum chamber during substrate transport. The vacuum chamber 1 is connected to an external vacuum pump through a vacuum tube. The placement platform 2 is fixed inside the vacuum chamber 1 by a mounting base 204 at the bottom. The bottom of the vacuum chamber 1 is a flat metal platform used to fix the mounting base 204 of the placement platform 2. The mounting base 204 is flush with the bottom of the vacuum chamber 1. The space is sealed with an oxygen-free copper metal sealing ring, eliminating the risk of air leakage. The placement platform 2 has a chamber 201 inside, and the upper surface of the placement platform 2 has several adsorption holes 202 that communicate with the chamber 201. The hole diameter is adapted to the airflow requirements of the substrate vacuum adsorption, so that the negative pressure suction can be evenly applied to the lower surface of the substrate. The bottom of the placement platform 2 is fixed in the mounting base 204 with an adsorption tube 2041 that communicates with the chamber 201. The adsorption tube 2041 passes through the vacuum chamber 1 and is connected to the external suction pump through a pressure-resistant sealed pipe. The pressing component 4 is installed inside the chamber 201. Two L-shaped pressure plates 3 are symmetrically arranged above the long side of the placement platform 2. The outer wall of the long side of the placement platform 2 is provided with a square through groove 203 communicating with the chamber 201. The vertical plates of the two L-shaped pressure plates 3 are connected to the pressing component 4 that passes through the square through groove 203. The blowing pipe 5 is horizontally arranged above the two L-shaped pressure plates 3. Both ends of the blowing pipe 5 are fixed with moving blocks 604. Multiple nozzles 501 are evenly arranged on the lower surface of the blowing pipe 5. One end of the blowing pipe 5 is connected to a flexible hose 502. The flexible hose 502 is made of high-vacuum Teflon material and has the characteristics of antistatic, high vacuum resistance, and plasma gas corrosion resistance. The flexible hose 502 passes through the corresponding moving block 604 and the mounting base 204 and is connected to the ion source outside the vacuum chamber 1 to realize plasma gas The body is conveyed without leakage. The bottom of each of the two moving blocks 604 is provided with a sliding groove 6041. The upper surface of each of the two L-shaped pressure plates 3 is fixed with a slide rail 302. The groove walls of each of the two sliding grooves 6041 are embedded with balls. Each of the two sliding grooves 6041 is slidably connected to the slide rail 302 through the embedded balls. The balls are made of hard alloy material, which can convert sliding friction into rolling friction, greatly reducing sliding resistance and eliminating the risk of frictional static electricity, thus ensuring the smoothness and stability of the moving blocks sliding along the slide rail. Inside the vacuum chamber 1, above each of the two moving blocks 604, there is a lead screw 6. Each of the two lead screws 6 is equipped with a moving block 602. The lower surface of each of the two moving blocks 602 is connected to the moving block 604 through a telescopic rod 603. Each of the two moving blocks 604 is slidably connected to the upper surface of the corresponding L-shaped pressure plate 3. Both ends of the two lead screws 6 are fixed with rotating shafts 601 via flanges. The end of each rotating shaft 601 is rotatably connected to the inner wall of the vacuum chamber 1. A drive box 103 is mounted on the outer wall of the vacuum chamber 1 above the inlet 101 via screws. The drive box 103 contains a chain drive mounted on the two rotating shafts 601 penetrating the vacuum chamber 1. The chain drive consists of two gears and a toothed chain (not shown in the prior art diagram). A drive motor 1031 is bolted to the outer wall of the drive box 103. The output end of the drive motor 1031 is connected to one of the rotating shafts 601 via a coupling. A magnetohydrodynamic seal is installed where the rotating shaft 601 penetrates the wall of the vacuum chamber 1. This magnetohydrodynamic seal enables simultaneous rotational transmission of the rotating shaft and complete... The vacuum chamber is completely isolated from the gas flow inside and outside, eliminating vacuum leakage and ensuring the high vacuum sealing requirements of the vacuum chamber. Flexible sealing covers 605 are provided on both sides of the two moving blocks 602 facing the rotating shaft 601. Each flexible sealing cover 605 has a mounting plate fixed at both ends. One end of the mounting plate of each flexible sealing cover 605 is sealed and welded to the outer wall of the moving block 602, and the other end of the mounting plate of each flexible sealing cover 605 is sealed and welded to the inner wall of the vacuum chamber 1. Each flexible sealing cover 605 is sleeved on the lead screw 6 and the rotating shaft 601. The ends of the two telescopic rods 603 are fixed to the bottom of the moving block 602 by screws, and the telescopic ends of the two telescopic rods 603 are fixedly connected to the top of the moving block 604 by screws.

[0022] First, the vacuum pump in vacuum chamber 1 is started to evacuate the interior of vacuum chamber 1, achieving the high vacuum level preset by the process. Then, the semiconductor substrate is transported through the inlet 101 of vacuum chamber 1 to the upper surface of the placement platform 2 via a vacuum isolation transfer structure (this structure is existing technology, such as a robotic arm, and therefore not described in detail). The substrate is positioned above the adsorption hole 202 and between the two L-shaped pressure plates 3 at a preset station. Next, an external suction pump is started. The suction pump continuously applies negative pressure to chamber 201 through the adsorption tube 2041, rapidly reducing the air pressure inside chamber 201. The resulting negative pressure suction... The adsorption holes 202 act uniformly on the lower surface of the substrate, forming a stable vacuum adsorption on the substrate. During the negative pressure suction process, the negative pressure in the chamber 201 will pull the three tents 401 of the pressing component 4 downward, thereby driving the movable plate 403 and the L-shaped pressure plate 3 to move down, so that the L-shaped pressure plate 3 moves closer to the surface of the placement platform 2 until the anti-static insulating soft pad 301 is tightly attached to the edge of the substrate, realizing flexible pressing of the substrate. The negative pressure suction of vacuum adsorption and the mechanical pressing force of the pressure plate work together to make the substrate tightly and flatly attached to the placement platform, eliminating the problem of local suspension or displacement of the substrate. During this process, the air blowing pipe 5 and the two side moving blocks 604 exert downward pulling force on the top telescopic rod 603 due to their own weight, causing the telescopic rod 603 to stretch naturally and complete the height adaptive adjustment. This ensures that the sliding groove 6041 at the bottom of the moving block 604 is always tightly connected to the slide rail 302 on the L-shaped pressure plate 3 through ball bearings. Then, the external ion source is activated, and the plasma gas generated by the ion source is delivered to the inside of the air blowing pipe 5 through the hose 502. After the plasma gas is evenly distributed in the air blowing pipe 5, it is ionized and sprayed out through the micro-perforated nozzle 501 on the lower surface, forming a uniform plasma airflow that directly acts on the upper surface of the substrate, neutralizing the static electricity on the substrate surface and achieving static elimination. At the same time, the drive motor 1031 is activated, and the drive motor 1031 drives the connected rotating shaft 60 through the coupling. 1. Rotation: The rotational power of the rotating shaft 601 is transmitted through gears and chains in the drive box 103, which drives the two lead screws 6 to rotate synchronously. The rotational motion of the lead screws 6 is converted into the horizontal linear sliding of the moving block 602 through the threaded engagement. The moving block 602 pulls the telescopic rod 603, which drives the moving block 604 to slide along the slide rail 302 on the L-shaped pressure plate 3. This drives the air blowing pipe 5 to perform reciprocating translational motion along the surface of the substrate, so that the plasma airflow can thoroughly and without dead angles sweep the entire upper surface of the substrate, ensuring that there is no static electricity residue on the substrate surface. During the horizontal linear sliding of the moving block 602, the flexible sealing cover 605 will adapt to the deformation as the moving block 602 moves, always maintaining the sealing protection of the lead screws 6 and the rotating shaft 601, preventing the high vacuum environment in the vacuum chamber 1 from being disturbed by external gases. After the electrostatic elimination of the substrate is completed, the ion source, drive motor 1031 and suction pump are turned off in sequence. After the suction pump stops, the negative pressure in the chamber 201 of the placement platform 2 gradually dissipates. The compression spring 404 resets under its own elastic rebound force, pushing the movable plate 403 to move vertically upward along the guide rod 402. The movable plate 403 drives the L-shaped pressure plate 3 to move upward synchronously, releasing the flexible pressure on the substrate. The tarpaulin 401 and the sealing folding plate 405 return to their initial state synchronously. Then, the vacuum isolation transmission structure transports the substrate that has completed electrostatic elimination to the next processing step through the outlet 102 of the vacuum chamber 1. The drive motor 1031 rotates in the opposite direction, driving the lead screw 6 to reset, so that the moving block 602, the moving block 604 and the blowing pipe 5 return to their initial positions. The telescopic rod 603 retracts and resets, and the vacuum chamber 1 can continue to carry out the electrostatic elimination operation of the next substrate, realizing continuous process production. This causes the negative pressure generated during the adsorption process to automatically traction the tarpaulin 401 to deform and press down, allowing the antistatic insulating pad 301 to flexibly press the edge of the substrate, uniformly dispersing the pressing force and avoiding physical damage to the substrate caused by local stress concentration. Combined with the reciprocating full-area scanning of the plasma blowing tube, complete coverage and uniformity of static elimination in a high vacuum environment are achieved, significantly improving product yield.

[0023] Please see Figure 5 and Figure 6As shown, the downward pressure assembly 4 includes three tarpaulins 401 and two movable plates 403. The three tarpaulins 401 are evenly distributed between the two movable plates 403, and all three tarpaulins 401 are fixed to the wall screws of the two movable plates 403. The tarpaulins 401 are made of fluororubber-based high-vacuum antistatic flexible material. The gaps reserved between the tarpaulins 401 are airflow channels in the chamber 201, which can accelerate the gas flow in the chamber during negative pressure suction and enhance the negative pressure stretching deformation effect of the tarpaulins 401. Both movable plates 403 are horizontally penetrating the square through-slots 203. Sealing folding plates 405 are fixed at the top and bottom of the two square through-slots 203. The end of each sealing folding plate 405 is fixedly connected to the surface of the movable plate 403. The side of the two movable plates 403 extending out of the square through-slots 203 is respectively connected to the corresponding L-shaped pressure plate. Plate 3 is fixedly connected to the vertical plate surface. Multiple guide rods 402 are provided on both sides of the interior of the chamber 201. Two movable plates 403 are located on one side of the chamber 201 and are slidably sleeved on the multiple guide rods 402. The two ends of the multiple guide rods 402 are fixedly connected to the top wall and bottom wall of the chamber 201, respectively. This can strictly limit the movable plates 403 to slide only in the vertical direction, without left or right offset, rotation or other displacement deviations, ensuring the verticality of the movable plates when they move down. Three compression springs 404 are fixed on the lower surface of the two movable plates 403. The bottom end of each compression spring 404 is fixedly connected to the bottom wall of the chamber 201. This can form an elastic buffer when the movable plates 403 move down. At the same time, the springs are connected to the movable plates 403 and the chamber 201, which can conduct the small amount of static electricity generated by sliding friction to the placement platform 2 to achieve static grounding. Both L-shaped pressure plates 3 have antistatic insulating pads 301 bonded to the side of the platen 2 closest to the upper surface of the platform. The pads are made of antistatic silicone and have high elasticity and insulation properties. They can form a flexible buffer when pressing the substrate to avoid indentation or cracking at the edge of the substrate, and can also prevent static electricity generated by friction during the pressing process. At the same time, the adhesive layer between the pads and the pressure plates is antistatic glue, so there is no risk of delamination or impurities falling off. The sealing folding plate 405 is made of flexible high vacuum sealing material, and the gap between it and the side wall of the square through groove 203 is filled with a sealing gasket. The sealing gasket is made of highly elastic oxygen-free copper material, which can fill the gap to achieve a seal.

[0024] When negative pressure suction is applied in the chamber 201 of the platform 2, a continuous downward pulling force is applied to the three tarpaulins 401, forcing the tarpaulins 401 to deform flexibly downward. The deformation of the tarpaulins 401 pulls the movable plates 403 on both sides to move vertically downward along the guide rod 402. As the movable plates 403 move downward, they squeeze the compression spring 404 at the bottom. The compression spring 404 forms an elastic buffer to control the downward speed of the movable plates 403. When the movable plates 403 slide, the sealing folding plate 405 in the square through groove 203 is stretched and compressed synchronously. Together with the sealing gasket, it always seals the gap of the through groove, maintains the vacuum seal of the chamber 201, and ensures the stability of the negative pressure adsorption. As the movable plates 403 move downward, they drive the L-shaped pressure plate 3 fixed to them to move synchronously, so that the antistatic insulating soft pad of the L-shaped pressure plate 3 approaches and adheres to the substrate, completing the flexible pressing. Furthermore, the linkage mechanism of negative pressure suction and pressing action eliminates the need for a separate pressure plate drive device. The pressing action is completed by utilizing the vacuuming process itself, which simplifies the equipment structure and simultaneously shortens the cycle time of substrate positioning and fixing, thereby improving the overall processing efficiency of the high vacuum mounting process.

[0025] The working principle of this invention is as follows: First, the vacuum pump in vacuum chamber 1 is started to evacuate the interior of vacuum chamber 1, achieving the high vacuum level preset by the process. Then, the semiconductor substrate is transported through the inlet 101 of vacuum chamber 1 to the upper surface of the placement platform 2 via a vacuum isolation transport structure, placing the substrate in a preset position above the adsorption hole 202 and between the two L-shaped pressure plates 3. Next, an external suction pump is started, continuously applying negative pressure to chamber 201 through the adsorption tube 2041. The air pressure inside chamber 201 rapidly decreases, and the resulting negative pressure suction acts evenly on the lower surface of the substrate through the adsorption hole 202, forming a stable vacuum adsorption on the substrate. During the negative pressure suction process, the negative pressure inside chamber 201 exerts a continuous downward force on the three tarpaulins 401. The pulling force forces the tarpaulin 401 to deform flexibly downwards. The deformation of the tarpaulin 401 pulls the movable plates 403 on both sides to move vertically downwards along the guide rod 402. As the movable plates 403 move downwards, they squeeze the compression spring 404 at the bottom. The compression spring 404 forms an elastic buffer to control the downward speed of the movable plates 403. When the movable plates 403 slide, the sealing folding plate 405 in the square through groove 203 is stretched and compressed in sync with it. Together with the sealing gasket, it always seals the gap of the through groove, maintains the vacuum seal of the chamber 201, and ensures the stability of the negative pressure adsorption. As the movable plates 403 move downwards, they drive the L-shaped pressure plate 3 fixed to them to move synchronously, so that the antistatic insulating soft pad of the L-shaped pressure plate 3 approaches the base plate and adheres to it, completing the flexible pressing. During this process, the air blowing pipe 5 and the two side moving blocks 604 exert downward pulling force on the top telescopic rod 603 due to their own weight, causing the telescopic rod 603 to stretch naturally and complete the height adaptive adjustment. This ensures that the sliding groove 6041 at the bottom of the moving block 604 is always tightly connected to the slide rail 302 on the L-shaped pressure plate 3 through ball bearings. Then, the external ion source is activated, and the plasma gas generated by the ion source is delivered to the inside of the air blowing pipe 5 through the hose 502. After the plasma gas is evenly distributed in the air blowing pipe 5, it is ionized and sprayed out through the micro-perforated nozzle 501 on the lower surface, forming a uniform plasma airflow that directly acts on the upper surface of the substrate, neutralizing the static electricity on the substrate surface and achieving static elimination. At the same time, the drive motor 1031 is activated, and the drive motor 1031 drives the connected rotating shaft 60 through the coupling. 1. Rotation: The rotational power of the rotating shaft 601 is transmitted through gears and chains in the drive box 103, which drives the two lead screws 6 to rotate synchronously. The rotational motion of the lead screws 6 is converted into the horizontal linear sliding of the moving block 602 through the threaded engagement. The moving block 602 pulls the telescopic rod 603, which drives the moving block 604 to slide along the slide rail 302 on the L-shaped pressure plate 3. This drives the air blowing pipe 5 to perform reciprocating translational motion along the surface of the substrate, so that the plasma airflow can thoroughly and without dead angles sweep the entire upper surface of the substrate, ensuring that there is no static electricity residue on the substrate surface. During the horizontal linear sliding of the moving block 602, the flexible sealing cover 605 will adapt to the deformation as the moving block 602 moves, always maintaining the sealing protection of the lead screws 6 and the rotating shaft 601, preventing the high vacuum environment in the vacuum chamber 1 from being disturbed by external gases. After the electrostatic elimination of the substrate is completed, the ion source, drive motor 1031 and suction pump are turned off in sequence. After the suction pump stops, the negative pressure in the chamber 201 of the placement platform 2 gradually dissipates. The compression spring 404 resets under its own elastic rebound force, pushing the movable plate 403 to move vertically upward along the guide rod 402. The movable plate 403 drives the L-shaped pressure plate 3 to move upward synchronously, releasing the flexible pressure on the substrate. The tarpaulin 401 and the sealing folding plate 405 return to their initial state synchronously. Then, the vacuum isolation transmission structure transports the substrate that has completed electrostatic elimination to the next processing step through the outlet 102 of the vacuum chamber 1. The drive motor 1031 rotates in the opposite direction, driving the lead screw 6 to reset, so that the moving block 602, the moving block 604 and the air blowing pipe 5 return to their initial positions. The telescopic rod 603 retracts and resets, and the vacuum chamber 1 can continue to carry out the electrostatic elimination operation of the next substrate, realizing continuous process production.

[0026] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the invention and are not intended to limit it. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the invention, but such modifications, substitutions, and variations are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. An electrostatic elimination process for a high vacuum device, characterized in that, Includes the following steps: Step 1: Adsorption of semiconductor substrate. The vacuum chamber (1) is evacuated to a preset high vacuum level. The substrate is transported through the inlet (101) to the upper surface of the placement platform (2) via the vacuum isolation transmission structure, so that the substrate is accurately placed above the adsorption hole (202) and between the two L-shaped pressure plates (3) at the preset position, thus completing the initial positioning of the substrate. Start the suction pump. The suction pump performs negative pressure suction on the built-in chamber (201) of the placement platform (2) through the suction tube (2041), so that the chamber (201) and the top suction hole (202) generate a continuous negative pressure suction force, forming a vacuum adsorption on the lower surface of the substrate. Step 2: Flexible pressing of the substrate. During the negative pressure suction process, the negative pressure will pull the three tarpaulins (401) of the pressing component (4) downward to undergo flexible deformation, and drive the movable plates (403) on both sides to move down and squeeze the compression spring (404). The sealing folding plate (405) adapts to deformation to keep the chamber (201) sealed. The movable plate (403) drives the L-shaped pressure plate (3) to move closer to the upper surface of the placement platform (2). The substrate is flexibly pressed by the anti-static insulating pad (301). Under the action of its own gravity, the air pipe (5) and the moving blocks (604) on both sides cause the telescopic rod (603) to stretch naturally. The adaptive adjustment can ensure that the moving block (604) is always tightly connected to the slide rail (302) on the L-shaped pressure plate (3). Step 3: Static elimination on the substrate. The external ion source is activated, and the plasma gas generated by the ion source is delivered to the blowing pipe (5) through the hose (502) and blown onto the substrate surface through the nozzle (501). At the same time, the drive motor (1031) outside the vacuum chamber (1) drives the two lead screws (6) to rotate synchronously through the gears and gear chains in the drive box (103), controlling the moving block (602) to slide back and forth and drive the blowing pipe (5) to move horizontally, so as to realize the full-area plasma gas blowing of the substrate to eliminate static electricity.

2. The electrostatic elimination process for a high-vacuum device according to claim 1, characterized in that, The vacuum chamber (1) has an inlet (101) and an outlet (102) on its two side walls respectively. The placement platform (2) is fixed in the vacuum chamber (1) by a mounting base (204) at the bottom. The placement platform (2) has a cavity (201) inside and a plurality of adsorption holes (202) communicating with the cavity (201) are opened on the upper surface of the placement platform (2). The bottom of the placement platform (2) is fixed in the mounting base (204) with an adsorption tube (2041) communicating with the cavity (201). The adsorption tube (2041) passes through the vacuum chamber (1) and is connected to an external suction pump through a pipe. The pressing component (4) is located inside the chamber (201). The two L-shaped pressure plates (3) are symmetrically arranged above the long side of the placement platform (2). The outer wall of the long side of the placement platform (2) is provided with a square through groove (203) that communicates with the chamber (201). The vertical plates of the two L-shaped pressure plates (3) are connected to the pressing component (4) that passes through the square through groove (203). The blowing pipe (5) is horizontally arranged above the two L-shaped pressure plates (3). Both ends of the blowing pipe (5) are fixed with moving blocks (604). The vacuum chamber (1) is provided with a lead screw (6) above the two moving blocks (604). The two lead screws (6) are equipped with moving blocks (602). The lower surfaces of the two moving blocks (602) are connected to the moving blocks (604) through telescopic rods (603). The two moving blocks (604) are slidably connected to the upper surfaces of the corresponding L-shaped pressure plates (3).

3. The electrostatic elimination process for a high-vacuum device according to claim 2, characterized in that, The pressing assembly (4) includes three tarpaulins (401) and two movable plates (403). The three tarpaulins (401) are evenly distributed between the two movable plates (403), and the three tarpaulins (401) are all fixed to the wall screws of the two movable plates (403). The two movable plates (403) are horizontally penetrating the square through groove (203). The top and bottom of the two square through grooves (203) are fixed with sealing folding plates (405). The end of each sealing folding plate (405) is fixedly connected to the surface of the movable plate (403). The side of the two movable plates (403) extending out of the square through groove (203) is fixedly connected to the vertical plate surface of the corresponding L-shaped pressure plate (3).

4. The electrostatic elimination process for a high-vacuum device according to claim 3, characterized in that, Multiple guide rods (402) are provided on both sides of the interior of the chamber (201). Two movable plates (403) are slidably sleeved on the multiple guide rods (402) on one side of the chamber (201). The two ends of the multiple guide rods (402) are fixedly connected to the top wall and bottom wall of the chamber (201) respectively. Three compression springs (404) are fixed on the lower surface of the two movable plates (403). The bottom end of each compression spring (404) is fixedly connected to the bottom wall of the chamber (201).

5. The electrostatic elimination process for a high vacuum device according to claim 3, characterized in that, Both L-shaped pressure plates (3) have antistatic insulating pads (301) bonded to the side of the upper surface of the placement platform (2). The sealing folding plate (405) is made of flexible high vacuum sealing material and is filled with sealing gaskets in the gap between it and the side wall of the square through groove (203).

6. The electrostatic elimination process for a high-vacuum device according to claim 2, characterized in that, The bottom ends of the two moving blocks (604) are provided with sliding grooves (6041), the upper surfaces of the two L-shaped pressure plates (3) are fixed with slide rails (302), the groove walls of the two sliding grooves (6041) are embedded with balls, and the two sliding grooves (6041) are slidably connected to the slide rails (302) through the embedded balls.

7. The electrostatic elimination process for a high-vacuum device according to claim 2, characterized in that, Both ends of the two lead screws (6) are fixed with rotating shafts (601) by flanges. The end of each rotating shaft (601) is rotatably connected to the inner wall of the vacuum chamber (1). The outer wall of the vacuum chamber (1) is located above the inlet (101) and a drive box (103) is installed by screws. The drive box (103) is equipped with a chain drive and is installed on the two rotating shafts (601) that pass through the vacuum chamber (1). The outer wall of the drive box (103) is bolted with a drive motor (1031). The output end of the drive motor (1031) is connected to a rotating shaft (601) by a coupling.

8. The electrostatic elimination process for a high vacuum device according to claim 7, characterized in that, The rotating shaft (601) is fitted with a magnetic fluid seal at the point where it penetrates the wall of the vacuum chamber (1). Both sides of the two moving blocks (602) facing the rotating shaft (601) are provided with flexible sealing covers (605). Each flexible sealing cover (605) has a mounting plate fixed at both ends. One end of the mounting plate of each flexible sealing cover (605) is sealed and welded to the outer wall of the moving block (602), and the other end of the mounting plate of each flexible sealing cover (605) is sealed and welded to the inner wall of the vacuum chamber (1). Each flexible sealing cover (605) is sleeved on the lead screw (6) and the rotating shaft (601).

9. The electrostatic elimination process for a high vacuum device according to claim 2, characterized in that, The ends of both telescopic rods (603) are fixed to the bottom of the moving block (602) by screws, and the telescopic ends of both telescopic rods (603) are fixedly connected to the top of the moving block (604) by screws.

10. The electrostatic elimination process for a high-vacuum device according to claim 2, characterized in that, The lower surface of the blowing pipe (5) is uniformly provided with multiple nozzles (501). One end of the blowing pipe (5) is connected to a flexible tube (502). The flexible tube (502) passes through the corresponding moving block (604) and the mounting base (204) and is connected to the ion source outside the vacuum chamber (1).

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