Edge over-polishing prevention chemical mechanical polishing equipment for polycrystalline silicon ring machining

Abstract

The invention relates to the technical field of chemical mechanical polishing of polycrystalline silicon rings, and discloses edge over-polishing prevention chemical mechanical polishing equipment for polycrystalline silicon ring machining, which comprises a base, a polishing disc is rotatably connected in the base, and a polishing pad is fixedly mounted on the upper surface of the polishing disc; and the polishing part comprises a center base, and an inner supporting piece used for positioning the polycrystalline silicon ring body is arranged on the outer surface of the circumference of the center base. The edge over-polishing-preventing chemical mechanical polishing equipment for polycrystalline silicon ring machining can effectively solve the problems that in the prior art, most of wafer polishing equipment is designed based on sheet workpieces and relies on vacuum adsorption or thin film pressure cavity pressure application, and an industrial-grade polycrystalline silicon ring is usually large in wall thickness, heavy in dead weight, high in rigidity, poor in polishing effect and the like. And when the equipment is applied to the thick-wall silicon ring, a workpiece is difficult to provide stable support due to the large dead weight of the workpiece, so that the workpiece is easy to displace or vibrate in the polishing process.

Description

Technical Field

[0001] This invention relates to the field of chemical mechanical polishing technology for polycrystalline silicon rings, and more specifically to a chemical mechanical polishing device for edge anti-overpolishing in polycrystalline silicon ring processing. Background Technology

[0002] In chemical mechanical polishing (CMP), a polycrystalline silicon ring is fixed to a polishing head. Pressure is applied and the ring is rotated, bringing it into contact with a high-speed rotating polishing pad. Simultaneously, polishing slurry is continuously supplied. Through the combined action of chemical etching and mechanical abrasion, the end-face material is removed. The polycrystalline silicon ring is a ring-shaped component made of high-purity polycrystalline silicon material, possessing advantages such as excellent semiconductor properties, high temperature resistance, corrosion resistance, and high hardness.

[0003] In the existing technology, most equipment used for wafer polishing is based on thin workpiece design and relies on vacuum adsorption or thin film pressure chamber to apply pressure. However, industrial-grade polycrystalline silicon rings usually have a large wall thickness, heavy weight, and high rigidity. When such equipment is applied to thick-walled silicon rings, due to the large weight of the workpiece, traditional carriers cannot provide stable support, which can easily lead to displacement or vibration of the workpiece during the polishing process. Summary of the Invention

[0004] To address the aforementioned shortcomings of existing technologies, this invention provides an edge-protected chemical mechanical polishing (CMP) device for processing polycrystalline silicon rings. This device effectively solves the problem that most existing wafer polishing equipment is designed for thin-film workpieces and relies on vacuum adsorption or thin-film pressure chambers for pressure application. However, industrial-grade polycrystalline silicon rings typically have thick walls, are heavy, and have high rigidity. When such equipment is applied to thick-walled silicon rings, the large weight of the workpiece makes it difficult for traditional carriers to provide stable support, which can easily lead to displacement or vibration of the workpiece during polishing.

[0005] To achieve the above objectives, the present invention provides the following technical solution: This invention provides an edge-protecting chemical mechanical polishing device for processing polycrystalline silicon rings, comprising: A base, wherein a polishing disc is rotatably connected inside the base, and a polishing pad is fixedly installed on the upper surface of the polishing disc; The polishing section includes a central seat, and an inner support member for positioning the polycrystalline silicon ring body is provided on the outer circumference of the central seat. An insertion groove is provided on the side of the central seat, and a drive column is fixedly connected to the upper surface of the base. A rotating shaft that fits against the inner wall surface of the insertion groove is connected to the side of the drive column near the central seat. The inner support includes a telescopic rod one fixedly connected to the outer surface of the center seat, a telescopic rod two slidably connected to the outer end of the telescopic rod one, and a pressing seat fixedly connected to the outer end of the telescopic rod two. The pressing seat is provided with an anti-detachment component through a groove formed inside it.

[0006] Furthermore, it also includes a trimming part, which includes a swing arm rotatably connected to the upper surface of the base, and a diamond disc is fixedly mounted on the output end of the swing arm.

[0007] Furthermore, multiple telescopic rods are provided, and the multiple telescopic rods are arranged in a circular array around the central seat. Each of the pressure seats has two sliding grooves inside, and the two sliding grooves are symmetrically distributed on the upper and lower sides of the pressure seat.

[0008] Furthermore, the anti-detachment component includes a sliding block, the inner surface of which is fixedly connected to a sliding rod that fits against the inner wall surface of the sliding groove, and the interior of the sliding groove is provided with a spring connected to the outer end of the sliding rod.

[0009] Furthermore, the sliding block is horizontally slidably connected to a limiting plate through a receiving groove formed inside it. One end of the limiting plate is rotatably connected to a rotating rod, and the end of the rotating rod away from the limiting plate is rotatably connected to a counterweight rod that slides perpendicularly inside the receiving groove.

[0010] Furthermore, the side of the pressure seat away from the center seat is designed with a rubber material that fits against the inner circumference of the polycrystalline silicon ring body, and the side of the pressure seat away from the center seat is designed with an arc surface.

[0011] Furthermore, the polishing section also includes a spindle, the bottom end of which engages with the interior of the center seat, and the outer surface of the center seat is provided with an outer ring that fits against the upper surface of the polishing pad, and the upper surface of the outer ring is provided with a groove.

[0012] Furthermore, a connecting plate is fixedly connected to the outer circumference of the main shaft, a limiting rod is slidably connected inside the connecting plate, a floating plate that slides with the outer surface of the main shaft is fixedly connected to the lower surface of the limiting rod, a compression spring connected to the lower surface of the connecting plate is sleeved on the outer circumference of the limiting rod, and a connecting arm that fits against the upper surface of the polycrystalline silicon ring body is fixedly connected to the outer surface of the floating plate.

[0013] The technical solution provided by this invention has the following advantages compared with the prior art: 1. This invention includes an internal support component, which comprises multiple telescopic rods (one and two) arranged in a circumferential array around a central seat, along with a pressure seat. This allows for synchronous telescopic movement, ensuring comprehensive and uniform fixation of the annular polycrystalline silicon ring. The side of the pressure seat furthest from the central seat is made of rubber material that adheres to the inner circumference of the polycrystalline silicon ring. This increases the adhesion and friction with the inner wall of the silicon ring, improving positioning stability, and effectively preventing scratches on the inner wall of the silicon ring during positioning. This solves the problem of existing metal or hard pressure structures easily damaging the silicon ring.

[0014] 2. This invention utilizes the cooperation of the drive column, rotating shaft, and center seat insertion slot to achieve flipping after one end face of the polysilicon ring body is polished, without removing the workpiece for external re-clamping. The spindle drives the center seat, inner support, and polysilicon ring body to a specific height. The rotating shaft on the drive column extends and embeds into the insertion slot on the side of the center seat. At this point, the spindle disengages from the center seat, and the rotating shaft rotates the center seat and workpiece 180°, so that the unpolished end face faces the polishing pad. This shortens the workpiece turnaround time, significantly improves the processing efficiency of double-sided polishing, and also reduces the risk of positioning errors caused by multiple clamping operations.

[0015] 3. The inner support's pressure seat contains an anti-detachment component consisting of a counterweight rod, a rotating rod, a limiting plate, and a spring. When the pressure seat is suspended (e.g., during workpiece handling or flipping), the lower counterweight rod slides downwards under gravity, pulling the lower limiting plate horizontally through the rotating rod. When the inner support is in the unfolded state to fix the polycrystalline silicon ring body, the limiting plate protrudes from the outer surface of the pressure seat and fits against the lower surface of the polycrystalline silicon ring body, forming a physical stop structure. This structure requires no additional power source or electrical control to automatically achieve vertical limiting of the polycrystalline silicon ring body, effectively solving the problem of workpiece easy detachment and displacement during suspended transport or flipping of existing inner support fixtures, greatly improving the safety and reliability of equipment operation. The anti-detachment component can also automatically avoid interference during polishing operations. When the pressure seat descends and contacts the polishing pad or loading table, the counterweight rod located below is first supported by an upward force, which drives the limit plate to automatically retract into the receiving groove. Subsequently, the sliding block compresses the spring and retracts completely into the slide groove. The anti-detachment component is completely hidden inside the pressure seat, avoiding interference with the inner wall of the workpiece or the polishing pad.

[0016] 4. This invention, through its connecting plate, floating plate, compression spring, and connecting arm, can adapt to the processing requirements of polycrystalline silicon rings of varying thicknesses. Especially after flipping, because the workpiece thickness is less than the thickness of the pressing seat, the floating plate, under the action of the compression spring, drives the connecting arm to elastically press down, automatically compensating for the thickness difference and ensuring a tight fit between the lower surface of the workpiece and the polishing pad. This flexible pressing mechanism not only avoids the risk of workpiece breakage caused by rigid contact but also enables the equipment to be compatible with polycrystalline silicon rings of various specifications and thicknesses, improving the equipment's versatility. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0018] Figure 1This is a three-dimensional structural diagram of an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the polishing disc, spindle, outer ring, and dressing part according to an embodiment of the present invention; Figure 3 This is a cross-sectional structural diagram of the polishing disc, polishing pad, spindle, and inner support component according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the separate structure of the main shaft and the center seat according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the main shaft, connecting plate, floating plate, and connecting arm according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the core seat, inner support, and rotating shaft in an embodiment of the present invention; Figure 7 This is a schematic diagram of the separation structure of the pressure seat and the anti-detachment component in an embodiment of the present invention; Figure 8 This is an embodiment of the present invention. Figure 3 A magnified structural diagram of part A in the middle; Figure 9 This is an embodiment of the present invention. Figure 3 A magnified structural diagram of section B in the middle; Figure 10 This is a three-dimensional structural diagram of the polycrystalline silicon ring body being processed according to an embodiment of the present invention.

[0019] The labels in the diagram represent: 100. Polycrystalline silicon ring body; 1. Base; 11. Polishing disc; 12. Polishing pad; 2. Polishing section; 21. Center seat; 211. Insertion groove; 22. Inner support; 221. Telescopic rod one; 222. Telescopic rod two; 223. Pressing seat; 2231. Slide groove; 23. Drive column; 231. Rotating shaft; 24. Anti-detachment component; 241. Sliding block; 2411. Receiving groove; 242. Slide rod; 243. Spring; 244. Limiting plate; 245. Rotating rod; 246. Counterweight rod; 25. Main shaft; 251. Connecting plate; 252. Limiting rod; 253. Floating plate; 254. Compression spring; 255. Connecting arm; 26. Outer ring; 261. Groove; 3. Finishing section; 31. Swing arm; 32. Diamond disc. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0021] The present invention will be further described below with reference to embodiments.

[0022] Example:

[0023] Please see Figures 1-10 This invention provides a technical solution: a chemical mechanical polishing device for edge anti-overpolishing in polycrystalline silicon ring processing, comprising: The base 1 has a polishing disc 11 rotatably connected inside it, and a polishing pad 12 is fixedly installed on the upper surface of the polishing disc 11. Polishing part 2 includes a center seat 21. The outer circumferential surface of the center seat 21 is provided with an inner support member 22 for positioning the polycrystalline silicon ring body 100. The side of the center seat 21 is provided with an insertion groove 211. The upper surface of the base 1 is fixedly connected with a drive column 23. The side of the drive column 23 near the center seat 21 is connected to a rotating shaft 231 that fits against the inner wall surface of the insertion groove 211. The inner support member 22 includes a telescopic rod 221 fixedly connected to the outer circumference of the center seat 21. The outer end of the telescopic rod 221 is slidably connected to a telescopic rod 222. The outer end of the telescopic rod 222 is fixedly connected to a pressing seat 223. The pressing seat 223 is provided with an anti-detachment member 24 through a groove 2231 opened inside it.

[0024] It also includes a trimming part 3, which includes a swing arm 31 rotatably connected to the upper surface of the base 1, and a diamond disc 32 is fixedly installed at the output end of the swing arm 31.

[0025] Multiple telescopic rods 221 are provided, and the multiple telescopic rods 221 are arranged in a circular array around the central seat 21. Each pressure seat 223 has two sliding grooves 2231 inside, and the two sliding grooves 2231 are symmetrically distributed on the upper and lower sides of the pressure seat 223.

[0026] The anti-detachment component 24 includes a sliding block 241, and a sliding rod 242 that fits against the inner wall surface of the sliding groove 2231 is fixedly connected to the inner surface of the sliding block 241. A spring 243 that is connected to the outer end of the sliding rod 242 is provided inside the sliding groove 2231.

[0027] The sliding block 241 is horizontally slidably connected to the limiting plate 244 through the receiving groove 2411 opened inside it. One end of the limiting plate 244 is rotatably connected to the rotating rod 245, and the end of the rotating rod 245 away from the limiting plate 244 is rotatably connected to the counterweight rod 246 that slides vertically inside the receiving groove 2411.

[0028] The side of the pressure seat 223 away from the center seat 21 is designed with a rubber material that fits against the inner circumference of the polycrystalline silicon ring body 100.

[0029] The polishing section 2 also includes a spindle 25. The bottom end of the spindle 25 engages with the interior of the center seat 21. The outer surface of the center seat 21 is provided with an outer ring 26 that fits against the upper surface of the polishing pad 12. The upper surface of the outer ring 26 is provided with a groove 261.

[0030] A connecting plate 251 is fixedly connected to the outer circumference of the main shaft 25. A limit rod 252 is slidably connected inside the connecting plate 251. A floating plate 253 that slides with the outer surface of the main shaft 25 is fixedly connected to the lower surface of the limit rod 252. A compression spring 254 that connects with the lower surface of the connecting plate 251 is sleeved on the outer circumference of the limit rod 252. A connecting arm 255 that fits against the upper surface of the polycrystalline silicon ring body 100 is fixedly connected to the outer surface of the floating plate 253.

[0031] In the initial state, the polycrystalline silicon ring body 100 is placed on the loading platform surface. The bottom end of the spindle 25 in the polishing section 2 is embedded inside the center seat 21. At this time, the spindle 25 is in a standby state, and the inner support 22 on the outer circumference of the center seat 21 is in a retracted state. The polycrystalline silicon ring body 100 to be processed is placed on the loading platform surface. The polishing disc 11 and polishing pad 12 are in a stationary state, and no polishing fluid is added to the surface of the polishing pad 12. The swing arm 31 of the trimming section 3 is in a retracted state, and the diamond disc 32 is not in contact with the polishing pad 12. The drive column 23 above the base 1 drives the rotating shaft 231 on its outer side to be in a retracted state, and the rotating shaft 231 on the drive column 23 is separated from the insertion groove 211 on the side of the center seat 21.

[0032] The connecting plate 251 is fixedly connected to the main shaft 25. The floating plate 253 is located below the connecting plate 251 and is slidably connected by the limiting rod 252. When not subjected to external force, the floating plate 253 is at its lowest point under the action of the compression spring 254. At this time, the connecting arm 255 is in a low position along with the floating plate 253 and is not in contact with the polycrystalline silicon ring body 100. Multiple telescopic rods 221 are arranged in a circumferential array around the central seat 21. The telescopic rod 222 is in the minimum extended state of the telescopic rod 221, and the pressing seat 223 is in a suspended state. Neither the upper nor lower end of the pressing seat 223 contacts the external structure.

[0033] At this time, the springs 243 are in the unfolded state in the sliding grooves 2231 on both the upper and lower sides of the pressure seat 223. The springs 243 drive the sliding blocks 241 to move to the outer end of the pressure seat 223 through the sliding rod 242: the upper surface of the upper sliding block 241 is higher than the top of the pressure seat 223, and the lower surface of the lower sliding block 241 protrudes from the bottom of the pressure seat 223. Since the pressure seat 223 is in a suspended state, the counterweight rod 246 inside it slides freely vertically within the receiving groove 2411 without being subjected to external pressure. Therefore, the upper counterweight rod 246 is located at the bottom of its stroke range. The upper surface of the counterweight rod 246 is flush with the top of the sliding block 241. The counterweight rod 246 pulls the limiting plate 244 through the rotating rod 245, so that the limiting plate 244 is in a retracted state and is completely housed inside the receiving groove 2411, without protruding from the surface of the sliding block 241. The lower counterweight rod 246 is also located at the bottom of its stroke range. The bottom end of the counterweight rod 246 protrudes from the lower surface of the sliding block 241. The counterweight rod 246 pulls the limiting plate 244 through its corresponding rotating rod 245, so that the limiting plate 244 moves away from the center seat 21 and is in an unfolded state. The limiting plate 244 slides horizontally and protrudes from the outer surface of the pressure seat 223.

[0034] The internal support positioning process of the polycrystalline silicon ring body 100: After the equipment is started, the spindle 25 begins to move, driving the center seat 21 and the inner support 22 towards the center of the polycrystalline silicon ring body 100 to be processed. During this process, the movement of the center seat 21 is precisely driven by the spindle 25, ensuring that the center seat 21 can move to the center of the polycrystalline silicon ring body 100. At the same time, the connecting plate 251 moves down with the spindle 25, and the connecting arm 255 gradually approaches the upper surface of the polycrystalline silicon ring body 100.

[0035] As the center seat 21 and the retracted inner support 22 continue to move towards the center of the polysilicon ring body 100, the lower surface of the pressure seat 223 in the inner support 22 gradually approaches the upper surface of the loading platform. At this time, the bottom end of the counterweight rod 246 protrudes from the lower surface of the sliding block 241, and the lower surface of the sliding block 241 protrudes from the bottom end of the pressure seat 223. During the movement towards the center of the polysilicon ring body 100, the bottom end of the counterweight rod 246 located inside the lower slide groove 2231 will be the first to contact the upper surface of the loading platform. As the center seat 21 and inner support 22 continue to move downward, the pressure seat 223 continues to press down. At this time, the counterweight rod 246 is supported by the upward force of the loading platform and moves relative to the inside of the sliding block 241, sliding vertically along the receiving groove 2411 to the top of its stroke range. During the upward sliding of the counterweight rod 246, the counterweight rod 246 drives the rotating rod 245 to rotate. The rotating rod 245 pulls the limiting plate 244 to move into the receiving groove 2411, so that the limiting plate 244 gradually retracts until the limiting plate 244 is completely housed inside the receiving groove 2411. At this time, the bottom ends of the counterweight rod 246 and the sliding block 241 are flush and in contact with the upper surface of the loading platform.

[0036] As the pressure seat 223 continues to move downward, the sliding block 241 located below is supported by the loading platform and moves relative to the pressure seat 223. The sliding block 241 moves into the sliding groove 2231 through the sliding rod 242. The sliding rod 242 applies pressure to the spring 243, causing the spring 243 to gradually undergo elastic deformation and begin to store elastic potential energy. During this process, the counterweight rod 246 located below always remains flush with the bottom of the sliding block 241 and adheres to the surface of the loading platform together with the sliding block 241 until the counterweight rod 246, the sliding block 241, and the pressure seat 223 are all flush with the upper surface of the loading platform and stably adhere to the surface of the loading platform, at which point the main shaft 25 stops moving downward. The telescopic rod 222, which was originally in a retracted state, then extends outward along the telescopic rod 221 in a direction away from the center seat 21, causing the inner support 22 to extend as a whole. This adjusts the distance between the pressure seat 223 and the center seat 21 until the side of the pressure seat 223 away from the center seat 21 begins to contact the inner circumference of the polycrystalline silicon ring body 100. The outer surface of the rubber pressure seat 223 is tightly fitted to the inner wall of the polycrystalline silicon ring body 100, thus initially achieving the positioning of the polycrystalline silicon ring body 100.

[0037] At this time, the upper surface of the sliding block 241 protrudes from the top of the pressure seat 223 under the action of the spring 243, and the upper counterweight rod 246 is still at the bottom of its stroke under the action of gravity, and pulls the limit plate 244 on this side to the retracted state through the rotating rod 245.

[0038] The process of feeding polycrystalline silicon ring body 100: After the inner support member 22 completes the stable positioning of the polycrystalline silicon ring body 100, the main shaft 25 drives the center seat 21, the inner support member 22 and the polycrystalline silicon ring body 100 to rise synchronously, and then move towards the polishing disk 11. When the pressure seat 223 in the inner support member 22 detaches from the surface of the loading table and is in a suspended state again, the sliding block 241 located in the lower slide groove 2231 extends downward first under the elastic force of the spring 243, protruding from the lower surface of the pressure seat 223 and the polycrystalline silicon ring body 100; then, the counterweight rod 246 located below extends downward along the receiving groove 2411 under its own gravity. The counterweight rod 246 slides downward and drives the rotating rod 245 to rotate synchronously. The inclination of the rotating rod 245 gradually decreases, pulling the limiting plate 244 outward. Finally, the limiting plate 244 protrudes to the outer surface of the pressure seat 223. At this time, the outer surface of the pressing seat 223 is in close contact with the inner circumference of the polycrystalline silicon ring body 100, and the limiting plate 244 is lower than the lower surface of the polycrystalline silicon ring body 100. It moves horizontally and protrudes from the inner circumference of the polycrystalline silicon ring body 100. The protruding limiting plate 244 can effectively limit the vertical displacement of the polycrystalline silicon ring body 100 and prevent it from falling off during the suspended transport process.

[0039] Under the anti-detachment protection of the limiting plate 244, the polycrystalline silicon ring body 100 moves smoothly into the interior of the outer ring 26 on the upper surface of the polishing pad 12. At this time, the connecting arm 255 under the connecting plate 251 is inserted into the groove 261 on the upper surface of the outer ring 26. The lower surface of the connecting arm 255 is in close contact with the upper end face of the polycrystalline silicon ring body 100, further realizing the positioning and limiting of the polycrystalline silicon ring body 100, ensuring that no displacement occurs during the polishing process, and completing the feeding of the polycrystalline silicon ring body 100.

[0040] Subsequently, the spindle 25 drives the center seat 21, inner support 22, and polysilicon ring body 100 to slowly move downwards. The lower surface of the pressure seat 223 gradually contacts the upper surface of the polishing pad 12. During this process, the anti-detachment component 24 inside the pressure seat 223 begins to retract again. The retraction process follows a fixed sequence: First, the counterweight rod 246 located below is forced to retract upwards along the receiving groove 2411 by the upward supporting force of the polishing pad 12. The counterweight rod 246 simultaneously drives the rotating rod 245 to rotate. The rotating rod 245 pulls the limiting plate 244 to move horizontally into the receiving groove 2411, realizing the limiting... The position plate 244 retracts until the limiting plate 244 is completely housed in the receiving groove 2411 and no longer protrudes from the outer surface of the pressing seat 223; then, under the squeezing action of the pressing seat 223 body, the sliding block 241 retracts inward along the sliding groove 2231 through the sliding rod 242, and simultaneously compresses the spring 243 to store elastic potential energy. Finally, the sliding block 241, the counterweight rod 246, and the limiting plate 244 are completely retracted inside the sliding groove 2231, ensuring that the outer side of the pressing seat 223 is in close contact with the inner circumference of the polycrystalline silicon ring body 100, thus preparing for subsequent polishing operations.

[0041] Polishing process of polycrystalline silicon ring body 100: After the polycrystalline silicon ring body 100 is loaded and positioned, the polishing disc 11 begins to rotate. The polishing disc 11 drives the polishing pad 12 on its upper surface to rotate synchronously. Simultaneously, polishing fluid is added to the surface of the polishing pad 12. Under the rotation of the polishing pad 12, the polishing fluid is evenly distributed on the contact surface between the polishing pad 12 and the polycrystalline silicon ring body 100, achieving chemical mechanical polishing of one end face of the polycrystalline silicon ring body 100. During this process, the spindle 25 drives the center seat 21 and the polycrystalline silicon ring body 100 to rotate synchronously. At this time, the rotating shaft 231 on the drive column 23 is separated from the insertion groove 211 on the side of the center seat 21. The rotating shaft 231 is higher than the height of the center seat 21 at this time, and does not affect the normal rotation of the center seat 21. The inner support 22 continuously provides internal support and positioning for the polycrystalline silicon ring body 100. The rubber material of the pressure seat 223 effectively increases the friction with the inner wall of the polycrystalline silicon ring body 100, preventing the polycrystalline silicon ring body 100 from shifting during the polishing process. Under the action of the compression spring 254, the connecting arm 255 remains in contact with the upper surface of the polycrystalline silicon ring body 100, further improving positioning stability. The outer ring 26 is in contact with the surface of the polishing pad 12. When the high-speed flowing polishing fluid flows through the side wall of the polycrystalline silicon ring body 100, it generates a direct fluid impact force. Without the outer ring 26, this impact would act directly on the side edge of the polycrystalline silicon ring body 100. Therefore, the outer ring 26 prevents the direct accumulation of polishing fluid at the edge, reduces the disordered penetration of chemical reagents into the side wall and bottom side of the silicon ring, thereby ensuring the geometric accuracy of the silicon ring edge and preventing side corrosion.

[0042] During the polishing process, the dressing unit 3 is activated, and the swing arm 31 begins to swing back and forth, driving the diamond disc 32 to move on the upper surface of the polishing pad 12. The surface of the polishing pad 12 is dressed by the rotation of the diamond disc 32, so that the surface of the polishing pad 12 remains flat and the polishing accuracy of the polycrystalline silicon ring body 100 is ensured.

[0043] The process of flipping the polycrystalline silicon ring body 100: After one end face of the polysilicon ring body 100 is polished, the spindle 25 drives the center seat 21, the inner support 22, and the polysilicon ring body 100 to move upwards synchronously, separating the polysilicon ring body 100 from the upper surface of the polishing pad 12. The spindle 25 moves upwards until the insertion groove 211 on the side of the center seat 21 is flush with the rotating shaft 231. Then, the rotating shaft 231 on the outer surface of the drive column 23 extends outwards and precisely inserts into the insertion groove 211 on the side of the center seat 21. The bottom end of the spindle 25 disengages from the center seat 21 and continues to rise away from the center seat 21. At this time, the rotating shaft 231 begins to rotate, driving the center seat 21, the inner support 22, and the polysilicon ring body 100 to rotate 180 degrees synchronously, ensuring that the unpolished end face of the polysilicon ring body 100 faces the polishing pad 12.

[0044] After the rotation is completed, the bottom of the spindle 25 engages with the inside of the center seat 21 again. Then, the spindle 25 drives the center seat 21, the inner support 22 and the polysilicon ring body 100 to move towards the upper surface of the polishing pad 12 until the unpolished end face of the polysilicon ring body 100 is in close contact with the polishing pad 12, ready to carry out the polishing operation of the next end face, and complete the flipping of the polysilicon ring body 100.

[0045] After one end face of the polycrystalline silicon ring body 100 is polished, the spindle 25 drives the center seat 21, the inner support 22, and the polycrystalline silicon ring body 100 to move upward synchronously, causing the polycrystalline silicon ring body 100 to separate from the upper surface of the polishing pad 12. During this process, the pressure seat 223 detaches from the surface of the polishing pad 12 and is suspended again. The anti-detachment component 24 located in the lower slide groove 2231 automatically unfolds: the spring 243 restores its elastic deformation, pushing the sliding block 241 to extend downward. At the same time, the counterweight rod 246 slides downward along the receiving groove 2411 under its own gravity, driving the rotating rod 245 to rotate, thereby pulling the limiting plate 244 to unfold outward and protrude from the outer surface of the pressure seat 223, fitting against the lower surface of the polycrystalline silicon ring body 100, preventing the polycrystalline silicon ring body 100 from falling off or shifting during the flipping process.

[0046] The main shaft 25 drives the center seat 21, inner support 22, and polysilicon ring body 100 to move upwards synchronously until the insertion groove 211 on the side of the center seat 21 is flush with the rotating shaft 231. Then, the rotating shaft 231 on the outer surface of the drive column 23 extends outwards and precisely embeds into the insertion groove 211 on the side of the center seat 21. The bottom end of the main shaft 25 disengages from the center seat 21 and continues to rise away from the center seat 21. At this time, the rotating shaft 231 begins to rotate, driving the center seat 21, inner support 22, and polysilicon ring body 100 to rotate 180 degrees synchronously, ensuring that the unpolished end face of the polysilicon ring body 100 faces the polishing pad 12. During this process, any anti-detachment component 24 located at the bottom remains in the extended state, which can stably limit the polysilicon ring body 100, achieving anti-detachment protection without additional operation, and balancing the smoothness of flipping and the stability of positioning. After the rotation is completed, the bottom end of the spindle 25 engages with the inside of the center seat 21 again, and the rotation shaft 231 on the outer surface of the drive column 23 retracts backward. Then, the spindle 25 drives the center seat 21, the inner support 22 and the polysilicon ring body 100 to move towards the upper surface of the polishing pad 12 until the unpolished end face of the polysilicon ring body 100 is tightly attached to the polishing pad 12, ready to carry out the polishing operation of the next end face, and complete the flipping of the polysilicon ring body 100.

[0047] The thickness of the polysilicon ring body 100 is less than the thickness of the pressure seat 223. Before flipping, the lower surface of the original polysilicon ring body 100 is flush with the lower surface of the pressure seat 223 and the upper surface of the polishing pad 12. After flipping, the upper surface of the polysilicon ring body 100 is flush with the upper surface of the pressure seat 223, and the lower surface of the polysilicon ring body 100 is higher than the lower surface of the pressure seat 223 and does not adhere to the upper surface of the polishing pad 12. At this time, the spindle 25 drives the center seat 21, the inner support 22 and the polycrystalline silicon ring body 100 to slowly press down. Under the elastic force of the compression spring 254, the floating plate 253 drives the connecting arm 255 to elastically press the upper surface of the polycrystalline silicon ring body 100, pushing the polycrystalline silicon ring body 100 to move downward until the lower surface of the polycrystalline silicon ring body 100 is once again in close contact with the upper surface of the polishing pad 12, completing the positioning. This method is suitable for processing polycrystalline silicon ring bodies 100 of different thicknesses, improving the applicability of the equipment.

[0048] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A chemical mechanical polishing (CMP) device for edge anti-overpolishing in polycrystalline silicon ring processing, characterized in that, include: A base (1) is rotatably connected to the inside of the base (1), and a polishing pad (12) is fixedly installed on the upper surface of the polishing pad (11). The polishing part (2) includes a center seat (21). The outer circumferential surface of the center seat (21) is provided with an inner support (22) for positioning the polycrystalline silicon ring body (100). The side of the center seat (21) is provided with a plug groove (211). The upper surface of the base (1) is fixedly connected with a drive column (23). The side of the drive column (23) near the center seat (21) is connected to a rotating shaft (231) that fits against the inner wall surface of the plug groove (211). The inner support member (22) includes a telescopic rod one (221) fixedly connected to the outer surface of the circumference of the center seat (21), a telescopic rod two (222) slidably connected to the outer end of the telescopic rod one (221), a pressure seat (223) fixedly connected to the outer end of the telescopic rod two (222), and an anti-detachment member (24) provided in the pressure seat (223) through a groove (2231) opened inside it.

2. The edge anti-overpolishing chemical mechanical polishing equipment for polycrystalline silicon ring processing according to claim 1, characterized in that: It also includes a trimming part (3), which includes a swing arm (31) rotatably connected to the upper surface of the base (1), and a diamond disc (32) is fixedly installed at the output end of the swing arm (31).

3. The edge anti-overpolishing chemical mechanical polishing equipment for polycrystalline silicon ring processing according to claim 1, characterized in that: Multiple telescopic rods (221) are provided, and the multiple telescopic rods (221) are arranged in a circular array around the central seat (21). Each pressure seat (223) has two sliding grooves (2231) inside, and the two sliding grooves (2231) are symmetrically distributed on the upper and lower sides of the pressure seat (223).

4. The edge anti-overpolishing chemical mechanical polishing equipment for polycrystalline silicon ring processing according to claim 3, characterized in that: The anti-detachment component (24) includes a sliding block (241), and a sliding rod (242) that fits against the inner wall surface of the sliding groove (2231) is fixedly connected to the inner surface of the sliding block (241). A spring (243) that connects to the outer end of the sliding rod (242) is provided inside the sliding groove (2231).

5. The edge anti-overpolishing chemical mechanical polishing equipment for polycrystalline silicon ring processing according to claim 4, characterized in that: The sliding block (241) is horizontally slidably connected to the limiting plate (244) through the receiving groove (2411) opened inside it. One end of the limiting plate (244) is rotatably connected to the rotating rod (245), and the end of the rotating rod (245) away from the limiting plate (244) is rotatably connected to the counterweight rod (246) that slides vertically inside the receiving groove (2411).

6. The edge anti-overpolishing chemical mechanical polishing equipment for polycrystalline silicon ring processing according to claim 3, characterized in that: The side of the pressure seat (223) away from the center seat (21) is designed with a rubber material that fits against the inner circumference of the polycrystalline silicon ring body (100).

7. The edge anti-overpolishing chemical mechanical polishing equipment for polycrystalline silicon ring processing according to claim 6, characterized in that: The polishing part (2) also includes a spindle (25), the bottom end of which engages with the interior of the center seat (21). The outer surface of the center seat (21) is provided with an outer ring (26) that fits against the upper surface of the polishing pad (12). The upper surface of the outer ring (26) is provided with a groove (261).

8. The edge anti-overpolishing chemical mechanical polishing equipment for polycrystalline silicon ring processing according to claim 7, characterized in that: A connecting plate (251) is fixedly connected to the outer circumference of the main shaft (25). A limiting rod (252) is slidably connected inside the connecting plate (251). A floating plate (253) that slides with the outer surface of the main shaft (25) is fixedly connected to the lower surface of the limiting rod (252). A compression spring (254) that connects with the lower surface of the connecting plate (251) is sleeved on the outer circumference of the limiting rod (252). A connecting arm (255) that fits against the upper surface of the polycrystalline silicon ring body (100) is fixedly connected to the outer surface of the floating plate (253).

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