Semiconductor wafer grinding device and grinding method thereof

Abstract

The invention relates to the technical field of semiconductor wafer grinding, in particular to a grinding device for a semiconductor wafer and a grinding method of the grinding device. Comprising a base, the base is fixedly connected with a protective cylinder for carrying out anti-splashing protection on grinding machining, and a wafer carrying table for limiting and fixing a semiconductor wafer is arranged in the protective cylinder; a second motor drives an adjusting block to rotate, and when a second gear rotates to a rack of an incomplete ring gear, the second gear rotates automatically through the meshing effect of the second gear and the incomplete ring gear, so that a lead screw is driven to rotate, and the grinding and polishing mechanism moves towards the central axis of the adjusting block by a small distance every time the grinding and polishing mechanism rotates by a circle; the surface of the semiconductor wafer is ground in a spiral mode, so that the surface of the semiconductor wafer is ground in a spiral mode, the device can conduct dead-corner-free grinding on the semiconductor wafers of different sizes, meanwhile, the uniformity of grinding precision is kept, and the yield of grinding finished products is effectively improved.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor wafer grinding, and in particular relates to a semiconductor wafer grinding device and a grinding method thereof. Background Art

[0002] Silicon wafers are the base material for semiconductor substrates. They need to be ground and polished with different precisions many times during the production process. Traditional semiconductor wafer grinding devices are not convenient for processing wafers of different sizes, which means that different sizes of wafers need to be processed with grinding discs of different sizes, resulting in poor universality of the device. The replacement of grinding discs can easily lead to changes in grinding precision, which in turn leads to a decrease in the yield rate of the finished product.

[0003] After searching, in the prior art, the authorized patent document with the announcement number of 2022.03.01 and the announcement date of 2022.03.01 discloses a substrate processing device for semiconductor production, which relates to the technical field of semiconductor production equipment, including a base, two transmission frames are provided on the left side of the top of the base; a polishing cylinder is provided on the right side of the transmission frame; a rotating seat is provided in the middle of the polishing cylinder, and a polishing turntable is provided on the rotating seat; a driving mechanism is provided at the bottom of the base, and a collecting component is provided on the right side of the driving mechanism. In the present invention, there is no need for complex driving and control components. As long as the double-headed motor is controlled, the transportation and polishing of the silicon wafer can be regulated, and by polishing the upper and lower surfaces of the silicon wafer at the same time, the process of changing the surface of the silicon wafer is saved, and the polishing efficiency is greatly improved, which solves the problem that the efficiency of single-side polishing of the silicon wafer is low. In addition, multiple sets of control and driving mechanisms are required for transportation and polishing, and the cost and power consumption of the equipment are high. At the same time, the residues produced by polishing are easily adsorbed on the surface of the silicon wafer, and the cleaning process is relatively troublesome.

[0004] However, the device still has the following defects: although it can polish both the upper and lower surfaces of the silicon wafer at the same time, the device is not convenient for processing wafers of different sizes, resulting in different sizes of wafers needing to be processed using grinding discs of different sizes, resulting in poor universality of the device and replacement of the grinding disc is prone to cause changes in grinding accuracy, thereby resulting in a decrease in the yield rate of the finished product. Summary of the invention

[0005] In view of the above problems, the present invention provides a semiconductor wafer grinding device and a grinding method thereof, comprising a base, to which a protective cylinder for splash protection during grinding is fixedly connected, and a wafer carrier for limiting and fixing the semiconductor wafer is arranged in the protective cylinder; The outer wall of the protective tube is provided with a thread, and a processing component is threadedly connected to the thread; The processing assembly includes a lifting platform for height adjustment, the lifting platform is configured as an internally threaded cylinder, and the lifting platform is threadedly connected to the thread on the protective cylinder; The lifting platform is fixedly connected with an L-shaped bracket, and the L-shaped bracket is provided with a driving mechanism and an adjusting mechanism for adjusting the processing height and position; The driving mechanism comprises a driving box, and an outer wall of the driving box is sleeved with an incomplete ring gear; The adjustment mechanism includes an adjustment block, a screw groove is opened in the adjustment block, a screw is rotatably connected in the screw groove, a first internal thread block is threadedly connected to the screw, and a grinding and polishing mechanism for grinding and polishing semiconductor wafers is fixedly connected to the bottom end of the first internal thread block.

[0006] Furthermore, a clearance groove is provided in the adjusting block, and a driven bevel gear is rotatably connected to an inner wall of one side of the clearance groove, and the center of the driven bevel gear is fixedly connected to one end of the screw rod, and a mounting bracket is fixedly connected to the adjusting block, and the bottom end of the mounting bracket is rotatably connected to an active bevel gear, and the active bevel gear is meshingly connected to the driven bevel gear, and a linkage shaft is fixedly connected to the top center of the active bevel gear, and a second gear is fixedly connected to the top of the linkage shaft, and the second gear is meshingly connected to the incomplete ring gear, and an adjustment handle is fixedly connected to the top center of the second gear.

[0007] Furthermore, a second internal thread block is threadedly connected to the screw rod, and a cooling mechanism is fixedly connected to the top of the second internal thread block. The cooling mechanism includes a coolant tank, the liquid outlet end of the coolant tank is connected to a liquid pump, the liquid outlet end of the liquid pump is connected to a liquid guide tube, the liquid outlet end of the liquid guide tube is connected to an annular tube, and the annular tube is connected to a plurality of groups of nozzles, and the plurality of groups of nozzles are distributed in an annular array with the central axis of the annular tube as the center.

[0008] Furthermore, the drive box is configured as a hollow cylinder, the top end of the drive box is fixedly connected to an L-shaped bracket, a second motor is installed in the drive box, and the output end of the second motor is transmission-connected to the top center of the adjustment block.

[0009] Furthermore, two groups of limit blocks are fixedly connected to the side walls of the lifting platform, an annular slide groove is opened on the lifting platform, and two groups of support shafts are fixedly connected to the bottom end of the adjustment block. The bottom ends of the two groups of support shafts are fixedly connected with sliding bolts, and the two groups of sliding bolts are movably fitted with the annular slide groove.

[0010] Furthermore, the grinding and polishing mechanism includes a box body, a plurality of groups of inclined brackets are fixedly connected to the outer wall of the box body, and the plurality of groups of inclined brackets are fixedly connected to the annular tube. A third motor is installed in the box body, and the output end of the third motor is transmission-connected to an electric slip ring, and the bottom end of the electric slip ring is electrically connected to a first electric cylinder, and the output end of the first electric cylinder is transmission-connected to an internal threaded barrel, and the bottom end of the internal threaded barrel is threadedly connected to a mounting bolt, and the bottom end of the mounting bolt is fixedly connected to a grinding disc.

[0011] Furthermore, an outer gear ring is sleeved on the protective tube, a first motor is installed on the base, an output end of the first motor is transmission-connected with a first gear, and the first gear is meshingly connected with the outer gear ring.

[0012] Furthermore, a hollow bracket is fixedly connected to the inner wall of the protective tube, a second electric cylinder is fixedly connected at the center of the hollow bracket, a telescopic waterproof cover is fixedly connected between the carrier stage and the hollow bracket, the second electric cylinder is arranged inside the telescopic waterproof cover, and the output end of the second electric cylinder is transmission-connected to a transmission platform, an articulated frame is fixedly connected to the transmission platform, a worm gear is rotatably connected to the side wall of the articulated frame, a rotating shaft is fixedly connected to the center of the worm gear, the rotating shaft is rotatably connected to the articulated frame, a linkage block is fixedly connected at the center of the bottom end of the carrier stage, the linkage block is fixedly connected to the rotating shaft, two groups of fixed plates are fixedly connected to the transmission platform, a worm is rotatably connected between the two groups of fixed plates, the worm is meshingly connected to the worm wheel, a fourth motor is mounted on one group of the fixed plates, and the output end of the fourth motor is transmission-connected to one end of the worm.

[0013] Furthermore, the bottom end of the protective tube is connected to a conical liquid guiding tube, and the bottom end of the conical liquid guiding tube is connected to a liquid discharge pipe, and a solenoid valve is provided on the liquid discharge pipe. Two sets of limit shafts are fixedly connected to the base, and the limit shafts are movably fitted with the processing component.

[0014] A grinding method for a semiconductor wafer grinding device, the grinding method comprising: Bonding the semiconductor wafer to the wafer stage for fixation; Adjust the grinding and polishing mechanism until the grinding disc moves to the edge of the semiconductor wafer; The protective tube rotates to move the processing assembly threadedly connected to the outer wall of the protective tube downward until the processing end of the grinding and polishing mechanism contacts the surface of the semiconductor wafer, thereby grinding the semiconductor wafer. The adjusting block rotates, driving the grinding and polishing mechanism to perform spiral grinding on the surface of the semiconductor wafer.

[0015] The beneficial effects of the present invention are: 1. The adjusting block is driven to rotate by the second motor, so that the grinding and polishing mechanism rotates around the central axis of the adjusting block to grind the surface of the semiconductor wafer. When the adjusting block rotates, the second gear rotates in contact with the surface of the incomplete ring gear. When the second gear rotates to the rack of the incomplete ring gear, the second gear rotates by meshing with the incomplete ring gear, thereby driving the screw to rotate, so that the grinding and polishing mechanism moves a short distance toward the central axis of the adjusting block every time it rotates one circle, thereby realizing spiral grinding of the surface of the semiconductor wafer, so that the device can grind semiconductor wafers of different sizes without dead angles while maintaining the uniformity of grinding accuracy, effectively improving the yield rate of finished grinding products.

[0016] 2. By turning the adjustment handle, the second gear drives the active bevel gear to rotate, and then the driven bevel gear drives the screw to rotate synchronously, so that the first internal thread block and the second internal thread block respectively drive the grinding and polishing mechanism and the cooling mechanism to move synchronously, so that the initial position of the grinding and polishing mechanism can be adjusted according to the size of the semiconductor wafer to be processed.

[0017] 3. The transmission table is driven upward to the top of the protective tube by the second electric cylinder to bond the semiconductor wafer to the wafer carrier for fixation. After the semiconductor wafer is bonded, the wafer carrier and the semiconductor wafer are driven downward to the protective tube for processing by the second electric cylinder, thereby avoiding splashing of debris and waste liquid generated during processing.

[0018] 4. The coolant in the coolant tank is introduced into the annular tube through a liquid pump, and finally sprayed to the processing surface of the grinding disc through several groups of nozzles. The processing surface is quickly cooled while the semiconductor wafer is ground, and the splash of debris is avoided. By keeping the grinding and polishing mechanism and the cooling mechanism moving synchronously, the spraying position of the coolant is kept consistent with the grinding processing position to improve the cooling effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic diagram of the main structure of an embodiment of the present invention is shown; Figure 2 A schematic diagram of an explosion of the internal structure of a protective tube according to an embodiment of the present invention is shown; Figure 3 A schematic diagram of the bottom structure of a wafer stage according to an embodiment of the present invention is shown; Figure 4 A schematic diagram of the structure of a processing assembly according to an embodiment of the present invention is shown; Figure 5 A partial structural cross-sectional view of a processing assembly according to an embodiment of the present invention is shown; Figure 6 The embodiment of the present invention is shown Figure 5 The enlarged schematic diagram at A in the middle; Figure 7 A schematic diagram of the structure of a grinding and polishing mechanism and a cooling mechanism according to an embodiment of the present invention is shown; Figure 8 An exploded schematic diagram of the grinding and polishing mechanism structure according to an embodiment of the present invention is shown.

[0021] In the figure: 1, base; 2, protective tube; 3, conical liquid guide tube; 4, drainage pipe; 5, solenoid valve; 6, carrier; 601, linkage block; 7, thread; 8, processing assembly; 801, lifting platform; 802, limit block; 803, L-shaped bracket; 804, driving mechanism; 8041, driving box; 8042, second motor; 8043, incomplete ring gear; 805, adjustment mechanism; 8051, adjustment block; 8052, screw groove; 8053, screw; 8054, first internal thread block; 8055, grinding and polishing mechanism; 80551, box; 80552, oblique bracket; 80553, third motor; 80554, electric slip ring; 80555, first electric cylinder; 80556, internal thread tube; 80557, grinding disc; 80558, mounting bolt ;8056, second internal thread block;8057, cooling mechanism;80571, coolant tank;80572, liquid guide tube;80573, annular tube;80574, nozzle;8058, support shaft;8059, slide bolt;80510, give way groove;80511, driven bevel gear;80512, mounting frame;80513, driving bevel gear;80514, linkage shaft;80515, second gear;80516, adjustment handle;806, annular slide groove;9, outer gear ring;10, first motor;11, first gear;12, limit shaft;13, hollow bracket;14, telescopic waterproof cover;15, second electric cylinder;16, transmission platform;17, articulated frame;18, worm gear;19, fixing plate;20, worm;21, fourth motor;22, rotating shaft. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The embodiment of the present invention provides a semiconductor wafer grinding device, including a base 1; illustratively, as Figure 1 shown.

[0024] The base 1 is fixedly connected with a protective tube 2, the bottom end of the protective tube 2 is connected with a conical liquid guide tube 3, the bottom end of the conical liquid guide tube 3 is connected with a liquid discharge pipe 4, the liquid discharge pipe 4 is provided with a solenoid valve 5, the protective tube 2 is provided with a wafer stage 6, and a semiconductor wafer is bonded to the wafer stage 6; Specifically, the semiconductor wafer is bonded to the wafer carrier 6 for fixation, and the grinding operation is performed in the protective tube 2 to effectively avoid the splashing of waste materials and waste liquid generated by grinding. By providing a conical liquid guide tube 3 and a drain pipe 4, the waste liquid generated by grinding can be discharged through the drain pipe 4, and the opening and closing of the drain pipe 4 is controlled by the solenoid valve 5.

[0025] The outer wall of the protective tube 2 is provided with a thread 7, and a processing assembly 8 is threadedly connected to the thread 7. Two sets of limiting shafts 12 are fixedly connected to the base 1, and the limiting shafts 12 are movably fitted with the processing assembly 8. The protective tube 2 is sleeved with an outer gear ring 9, and the base 1 is mounted with a first motor 10. The output end of the first motor 10 is transmission-connected with a first gear 11, and the first gear 11 is meshedly connected with the outer gear ring 9. Specifically, the first motor 10 drives the first gear 11 to rotate, so that the outer gear ring 9 drives the protective tube 2 to rotate synchronously, so that the processing assembly 8 threadedly connected to the outer wall of the protective tube 2 moves up and down, and the height adjustment of the processing assembly 8 is achieved.

[0026] For example, Figure 2 and Figure 3 shown.

[0027] The inner wall of the protective tube 2 is fixedly connected to a hollow bracket 13, and the center of the hollow bracket 13 is fixedly connected to a second electric cylinder 15. A telescopic waterproof cover 14 is fixedly connected between the carrier 6 and the hollow bracket 13. The second electric cylinder 15 is arranged inside the telescopic waterproof cover 14. The output end of the second electric cylinder 15 is transmission-connected to a transmission platform 16, and an articulated frame 17 is fixedly connected to the transmission platform 16. The side wall of the articulated frame 17 is rotationally connected to a worm gear 18, and the center of the worm gear 18 A rotating shaft 22 is fixedly connected at the center of the bottom end of the carrier 6, and the rotating shaft 22 is rotatably connected to the hinge frame 17. A linkage block 601 is fixedly connected at the center of the bottom end of the carrier 6, and the linkage block 601 is fixedly connected to the rotating shaft 22. Two groups of fixed plates 19 are fixedly connected to the transmission platform 16, and a worm 20 is rotatably connected between the two groups of fixed plates 19. The worm 20 is meshed with the worm wheel 18. A fourth motor 21 is installed on one group of the fixed plates 19, and the output end of the fourth motor 21 is transmission-connected to one end of the worm 20; Specifically, the second electric cylinder 15 drives the transmission table 16 to move up and down, so that the wafer carrier 6 drives the semiconductor wafer to move up and down. When the wafer carrier 6 drives the semiconductor wafer to move upward to the top of the protective tube 2, it is convenient to load and unload the semiconductor wafer. When the semiconductor wafer needs to be ground, the second electric cylinder 15 drives the semiconductor wafer to move downward to the inside of the protective tube 2, and the fourth motor 21 drives the worm 20 to rotate, so that the worm gear 18 drives the wafer carrier 6 to rotate to an inclined state, so that the debris and waste liquid remaining on the wafer carrier 6 flow into the protective tube 2, so that the wafer carrier 6 is kept clean, which is convenient for continuous grinding of multiple groups of semiconductor wafers. The second electric cylinder 15 and the fourth motor 21 are waterproofed by setting a telescopic waterproof cover 14, which effectively extends the service life of the equipment.

[0028] For example, Figure 4-6 shown.

[0029] The processing assembly 8 includes a lifting platform 801, which is configured as an internally threaded cylinder. The lifting platform 801 is threadedly connected to the thread 7 on the protective cylinder 2. The side wall of the lifting platform 801 is fixedly connected with two groups of limit blocks 802. The two groups of limit blocks 802 are movably fitted with two groups of limit shafts 12 respectively. The lifting platform 801 is fixedly connected with an L-shaped bracket 803. The L-shaped bracket 803 is provided with a driving mechanism 804 and an adjusting mechanism 805. The lifting platform 801 is provided with an annular slide groove 806. The driving mechanism 804 includes a driving box 8041, which is configured as a hollow cylinder. The top of the driving box 8041 is fixedly connected to the L-shaped bracket 803. A second motor 8042 is installed in the driving box 8041. An incomplete ring gear 8043 is sleeved on the outer wall of the driving box 8041. The adjusting mechanism 805 comprises an adjusting block 8051, the top center of the adjusting block 8051 is drivingly connected to the output end of the second motor 8042, a screw slot 8052 is provided in the adjusting block 8051, a screw 8053 is rotatably connected in the screw slot 8052, a first internal thread block 8054 is threadedly connected to the screw 8053, a polishing mechanism 8055 is fixedly connected to the bottom end of the first internal thread block 8054, a second internal thread block 8056 is threadedly connected to the screw 8053, and a cooling mechanism 8057 is fixedly connected to the top end of the second internal thread block 8056; The bottom end of the adjustment block 8051 is fixedly connected with two groups of support shafts 8058, and the bottom ends of the two groups of support shafts 8058 are fixedly connected with sliding bolts 8059, and the two groups of sliding bolts 8059 are movably fitted with the annular sliding groove 806; The adjusting block 8051 is provided with a giving way groove 80510, and a driven bevel gear 80511 is rotatably connected to an inner wall of one side of the giving way groove 80510, and the center of the driven bevel gear 80511 is fixedly connected to one end of the screw rod 8053, and a mounting frame 80512 is fixedly connected to the adjusting block 8051, and a driving bevel gear 80513 is rotatably connected to the bottom end of the mounting frame 80512, and the driving bevel gear 80513 is meshingly connected with the driven bevel gear 80511, and a linkage shaft 80514 is fixedly connected to the top center of the driving bevel gear 80513, and a second gear 80515 is fixedly connected to the top of the linkage shaft 80514, and the second gear 80515 is meshingly connected with the incomplete ring gear 8043, and an adjusting handle 80516 is fixedly connected to the top center of the second gear 80515; Specifically, the adjusting handle 80516 is rotated to make the second gear 80515 drive the active bevel gear 80513 to rotate, and then the driven bevel gear 80511 drives the screw rod 8053 to rotate synchronously, so that the first internal thread block 8054 and the second internal thread block 8056 respectively drive the grinding and polishing mechanism 8055 and the cooling mechanism 8057 to move synchronously, so that the initial position of the grinding and polishing mechanism 8055 can be adjusted according to the size of the semiconductor wafer to be processed; Furthermore, the second motor 8042 drives the adjusting block 8051 to rotate, so that the grinding and polishing mechanism 8055 rotates around the central axis of the adjusting block 8051 to grind the surface of the semiconductor wafer. When the adjusting block 8051 rotates, the second gear 80515 rotates in contact with the surface of the incomplete ring gear 8043. When the second gear 80515 rotates to the rack of the incomplete ring gear 8043, the second gear 80515 rotates on itself through the meshing action of the second gear 80515 and the incomplete ring gear 8043, thereby driving the screw rod 8053 to rotate, so that the grinding and polishing mechanism 8055 moves a short distance toward the central axis of the adjusting block 8051 every time it rotates one circle, thereby realizing spiral grinding of the surface of the semiconductor wafer, so that the device can grind semiconductor wafers of different sizes without dead angles while maintaining the uniformity of grinding accuracy, effectively improving the yield rate of the finished grinding products.

[0030] For example, Figure 5 , 7 and Figure 8 shown.

[0031] The cooling mechanism 8057 comprises a cooling liquid tank 80571, the liquid outlet end of the cooling liquid tank 80571 is connected to a liquid pump, the liquid outlet end of the liquid pump is connected to a liquid guide tube 80572, the liquid outlet end of the liquid guide tube 80572 is connected to an annular tube 80573, the annular tube 80573 is connected to a plurality of groups of nozzles 80574, and the plurality of groups of nozzles 80574 are distributed in an annular array with the central axis of the annular tube 80573 as the center; The grinding and polishing mechanism 8055 includes a box body 80551, and the outer wall of the box body 80551 is fixedly connected to a plurality of groups of inclined brackets 80552, and the plurality of groups of inclined brackets 80552 are fixedly connected to the annular tube 80573. A third motor 80553 is installed in the box body 80551, and the output end of the third motor 80553 is transmission-connected to an electric slip ring 80554, and the bottom end of the electric slip ring 80554 is electrically connected to a first electric cylinder 80555, and the output end of the first electric cylinder 80555 is transmission-connected to an internal threaded barrel 80556, and the bottom end of the internal threaded barrel 80556 is threadedly connected to a mounting bolt 80558, and the bottom end of the mounting bolt 80558 is fixedly connected to a grinding disc 80557; Specifically, the grinding disc 80557 is driven to rotate by the third motor 80553 to grind the semiconductor wafer, and the grinding disc 80557 is driven to move up and down by the first electric cylinder 80555 to meet the processing requirements of semiconductor wafers of different thicknesses. The installation method of threaded connection between the mounting bolt 80558 and the internal threaded tube 80556 is adopted to facilitate the replacement of the grinding disc 80557, so that the device can meet the different processing requirements of rough grinding and thinning and fine grinding and polishing. The coolant in the coolant tank 80571 is introduced into the annular tube 80573 by a liquid pump, and finally sprayed to the processing surface of the grinding disc 80557 through several groups of nozzles 80574, so that the semiconductor wafer is ground and the processing surface is quickly cooled while the splash of debris is avoided.

[0032] The working principle of the semiconductor wafer grinding device proposed by the present invention is as follows: The transmission platform 16 is driven by the second electric cylinder 15 to move upward to the top of the protective tube 2, and the semiconductor wafer is bonded to the carrier stage 6 for fixation. After the semiconductor wafer is bonded, the carrier stage 6 and the semiconductor wafer are driven by the second electric cylinder 15 to move downward into the protective tube 2 for processing, thereby avoiding splashing of debris and waste liquid generated during processing.

[0033] By rotating the adjustment handle 80516, the second gear 80515 drives the active bevel gear 80513 to rotate, and then the driven bevel gear 80511 drives the screw rod 8053 to rotate synchronously, so that the first internal thread block 8054 and the second internal thread block 8056 respectively drive the grinding and polishing mechanism 8055 and the cooling mechanism 8057 to move synchronously, so that the initial position of the grinding and polishing mechanism 8055 can be adjusted according to the size of the semiconductor wafer to be processed.

[0034] The first motor 10 drives the first gear 11 to rotate, so that the outer gear ring 9 drives the protective tube 2 to rotate synchronously, so that the processing component 8 threadedly connected to the outer wall of the protective tube 2 moves downward, so that the processing end of the grinding disk 80557 contacts the surface of the semiconductor wafer, and the grinding disk 80557 is driven by the third motor 80553 to rotate to grind the semiconductor wafer. The grinding disk 80557 is driven by the first electric cylinder 80555 to move up and down to meet the processing requirements of semiconductor wafers of different thicknesses.

[0035] The second motor 8042 drives the adjusting block 8051 to rotate, so that the grinding and polishing mechanism 8055 rotates around the central axis of the adjusting block 8051 to grind the surface of the semiconductor wafer. When the adjusting block 8051 rotates, the second gear 80515 rotates in contact with the surface of the incomplete ring gear 8043. When the second gear 80515 rotates to the rack of the incomplete ring gear 8043, the second gear 80515 rotates on itself through the meshing action of the second gear 80515 and the incomplete ring gear 8043, thereby driving the screw rod 8053 to rotate, so that the grinding and polishing mechanism 8055 moves a short distance toward the central axis of the adjusting block 8051 every time it rotates one circle, thereby realizing spiral grinding of the surface of the semiconductor wafer, so that the device can grind semiconductor wafers of different sizes without dead angles while maintaining the uniformity of grinding accuracy, effectively improving the yield rate of the finished grinding products.

[0036] The coolant in the coolant tank 80571 is introduced into the annular tube 80573 through a liquid pump, and finally sprayed to the processing surface of the grinding disc 80557 through several groups of nozzles 80574, so that the processing surface is quickly cooled while grinding the semiconductor wafer, and the splashing of debris is avoided. By keeping the grinding and polishing mechanism 8055 and the cooling mechanism 8057 moving synchronously, the spraying position of the coolant is kept consistent with the grinding processing position to improve the cooling effect.

[0037] After completing the grinding operation, the first motor 10 drives the first gear 11 to rotate in the opposite direction, so that the outer gear ring 9 drives the protective tube 2 to rotate in the opposite direction synchronously, thereby making the processing component 8 threadedly connected to the outer wall of the protective tube 2 move upward, and the grinding disc 80557 moves to the outside of the protective tube 2. At this time, the grinding disc 80557 can be removed by rotating the grinding disc 80557, and the grinding disc 80557 with different grinding precision can be replaced according to the processing requirements to realize the operations of rough grinding and thinning and fine grinding and polishing.

[0038] During the upward movement of the processing component 8, the protective tube 2 drives the wafer stage 6 and the semiconductor wafer inside it to rotate simultaneously. Through the action of centrifugal force, the debris and waste liquid attached to the wafer stage 6 and the semiconductor wafer are thrown into the protective tube 2. The worm 20 is driven by the fourth motor 21 to rotate, so that the worm gear 18 drives the wafer stage 6 to rotate to an inclined state, and the debris and waste liquid remaining on the wafer stage 6 flow into the protective tube 2, so that the wafer stage 6 is kept clean, which is convenient for continuous grinding processing of multiple groups of semiconductor wafers. The second electric cylinder 15 and the fourth motor 21 are waterproofed by setting a telescopic waterproof cover 14, which effectively extends the service life of the equipment.

[0039] By providing the conical liquid guiding cylinder 3 and the liquid draining pipe 4 , the waste liquid generated by grinding can be discharged through the liquid draining pipe 4 for centralized treatment, and the opening and closing of the liquid draining pipe 4 is controlled by the electromagnetic valve 5 .

[0040] Based on the above-mentioned semiconductor wafer grinding device, an embodiment of the present invention further proposes a grinding method for the grinding device. Exemplarily, the grinding method includes: Turn on the second electric cylinder to drive the transmission platform to move upward to the top of the protective tube; Bonding the semiconductor wafer to the wafer stage for fixation; The second electric cylinder is turned on to drive the wafer carrier and the semiconductor wafer to move downward into the protective tube; Turn the adjustment handle, and the grinding and polishing mechanism and the cooling mechanism move synchronously until the grinding disc moves to the edge of the semiconductor wafer; Turning on the first motor to drive the first gear to rotate, so that the outer gear ring drives the protective tube to rotate synchronously, so that the processing component threadedly connected to the outer wall of the protective tube moves downward until the processing end of the grinding disc contacts the surface of the semiconductor wafer; The third motor is turned on to drive the grinding disc to rotate, so as to grind the semiconductor wafer; The first electric cylinder is turned on to drive the grinding disc to move up and down to meet the processing requirements of semiconductor wafers of different thicknesses; Turn on the second motor to drive the adjusting block to rotate, so that the grinding and polishing mechanism rotates around the central axis of the adjusting block; When the second gear rotates to the rack of the incomplete ring gear, the second gear rotates on its own, thereby driving the screw to rotate, so that the grinding and polishing mechanism moves a short distance toward the central axis of the adjustment block every time it rotates one circle, thereby realizing spiral grinding of the surface of the semiconductor wafer; The liquid pump is turned on to guide the coolant in the coolant tank into the annular tube, and finally sprayed to the processing surface of the grinding disc through a plurality of nozzles, so as to grind the semiconductor wafer and cool the processing surface quickly; After the grinding operation is completed, the first motor is turned on to drive the first gear to rotate in the opposite direction, so that the outer gear ring drives the protective tube to rotate in the opposite direction synchronously, so that the processing component threadedly connected to the outer wall of the protective tube moves upward, and the grinding disc moves to the outside of the protective tube. At this time, the grinding discs with different precisions can be replaced; As the processing assembly moves upward, the protective cylinder drives the wafer carrier and the semiconductor wafer inside it to rotate simultaneously, and through the action of centrifugal force, the debris and waste liquid attached to the wafer carrier and the semiconductor wafer are thrown out into the protective cylinder; The fourth motor is turned on to drive the worm to rotate, so that the worm wheel drives the wafer stage to rotate to an inclined state, so that the debris and waste liquid remaining on the wafer stage flow into the protective tube, thereby keeping the wafer stage clean and facilitating the processing operation of the next group of semiconductor wafers.

[0041] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A semiconductor wafer grinding device, comprising a base, characterized in that: The base is fixedly connected with a protective cylinder for splash protection during grinding, and a wafer carrier for limiting and fixing the semiconductor wafer is arranged in the protective cylinder; The outer wall of the protective tube is provided with a thread, and a processing component is threadedly connected to the thread; The processing assembly includes a lifting platform for height adjustment, the lifting platform is configured as an internally threaded cylinder, and the lifting platform is threadedly connected to the thread on the protective cylinder; The lifting platform is fixedly connected with an L-shaped bracket, and the L-shaped bracket is provided with a driving mechanism and an adjusting mechanism for adjusting the processing height and position; The driving mechanism comprises a driving box, and an outer wall of the driving box is sleeved with an incomplete ring gear; The adjustment mechanism includes an adjustment block, a screw groove is opened in the adjustment block, a screw is rotatably connected in the screw groove, a first internal thread block is threadedly connected to the screw, and a grinding and polishing mechanism for grinding and polishing semiconductor wafers is fixedly connected to the bottom end of the first internal thread block.

2. The semiconductor wafer polishing device according to claim 1, wherein: A clearance groove is provided in the adjusting block, and a driven bevel gear is rotatably connected to an inner wall of one side of the clearance groove, and the center of the driven bevel gear is fixedly connected to one end of the screw rod, and a mounting bracket is fixedly connected to the adjusting block, and the bottom end of the mounting bracket is rotatably connected to a driving bevel gear, and the driving bevel gear is meshingly connected with the driven bevel gear, and a linkage shaft is fixedly connected to the top center of the driving bevel gear, and a second gear is fixedly connected to the top of the linkage shaft, and the second gear is meshingly connected with the incomplete ring gear, and an adjusting handle is fixedly connected to the top center of the second gear.

3. The semiconductor wafer polishing device according to claim 2, characterized in that: A second internal thread block is threadedly connected to the screw rod, and a cooling mechanism is fixedly connected to the top of the second internal thread block. The cooling mechanism includes a coolant tank, a liquid outlet end of the coolant tank is connected to a liquid pump, a liquid outlet end of the liquid pump is connected to a liquid guide tube, a liquid outlet end of the liquid guide tube is connected to an annular tube, and a plurality of groups of nozzles are connected to the annular tube, and the plurality of groups of nozzles are distributed in an annular array with the central axis of the annular tube as the center.

4. The semiconductor wafer polishing device according to claim 1, wherein: The driving box is configured as a hollow cylinder, the top end of which is fixedly connected to an L-shaped bracket, a second motor is installed in the driving box, and an output end of the second motor is drivingly connected to the top center of the regulating block.

5. The semiconductor wafer polishing device according to claim 1, wherein: Two groups of limit blocks are fixedly connected to the side walls of the lifting platform, an annular slide groove is opened on the lifting platform, two groups of support shafts are fixedly connected to the bottom ends of the adjustment blocks, and sliding bolts are fixedly connected to the bottom ends of the two groups of support shafts, and the two groups of sliding bolts are movably fitted with the annular slide groove.

6. The semiconductor wafer polishing device according to claim 1, wherein: The grinding and polishing mechanism includes a box body, and a plurality of groups of inclined brackets are fixedly connected to the outer wall of the box body, and the plurality of groups of inclined brackets are fixedly connected to the annular tube. A third motor is installed in the box body, and the output end of the third motor is transmission-connected to an electric slip ring, and the bottom end of the electric slip ring is electrically connected to a first electric cylinder, and the output end of the first electric cylinder is transmission-connected to an internal threaded barrel, and the bottom end of the internal threaded barrel is threadedly connected to a mounting bolt, and the bottom end of the mounting bolt is fixedly connected to a grinding disc.

7. The semiconductor wafer polishing device according to claim 1, wherein: An outer gear ring is sleeved on the protective tube, a first motor is installed on the base, an output end of the first motor is transmission-connected with a first gear, and the first gear is meshingly connected with the outer gear ring.

8. The semiconductor wafer polishing device according to claim 7, wherein: A hollow bracket is fixedly connected to the inner wall of the protective cylinder, a second electric cylinder is fixedly connected at the center of the hollow bracket, a telescopic waterproof cover is fixedly connected between the carrier stage and the hollow bracket, the second electric cylinder is arranged inside the telescopic waterproof cover, the output end of the second electric cylinder is transmission-connected to a transmission platform, an articulated frame is fixedly connected to the transmission platform, a worm gear is rotatably connected to the side wall of the articulated frame, a rotating shaft is fixedly connected to the center of the worm gear, the rotating shaft is rotatably connected to the articulated frame, a linkage block is fixedly connected at the center of the bottom end of the carrier stage, the linkage block is fixedly connected to the rotating shaft, two groups of fixed plates are fixedly connected to the transmission platform, a worm is rotatably connected between the two groups of fixed plates, the worm is meshingly connected to the worm wheel, a fourth motor is mounted on one group of the fixed plates, and the output end of the fourth motor is transmission-connected to one end of the worm.

9. The semiconductor wafer polishing device according to claim 8, characterized in that: The bottom end of the protective tube is connected to a conical liquid guiding tube, and the bottom end of the conical liquid guiding tube is connected to a liquid discharge pipe, and a solenoid valve is arranged on the liquid discharge pipe. Two groups of limit shafts are fixedly connected to the base, and the limit shafts are movably fitted with the processing component.

10. A grinding method for a semiconductor wafer grinding device according to any one of claims 1 to 9, characterized in that: The grinding method comprises: Bonding the semiconductor wafer to the wafer stage for fixation; Adjust the grinding and polishing mechanism until the grinding disc moves to the edge of the semiconductor wafer; The protective tube rotates to move the processing assembly threadedly connected to the outer wall of the protective tube downward until the processing end of the grinding and polishing mechanism contacts the surface of the semiconductor wafer, thereby grinding the semiconductor wafer. The adjusting block rotates, driving the grinding and polishing mechanism to perform spiral grinding on the surface of the semiconductor wafer.

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