Progressive single crystal silicon wafer grinding device and processing method thereof

Abstract

The application relates to the technical field of single crystal silicon wafer processing, in particular to a progressive single crystal silicon wafer grinding processing device and a processing method thereof. The device comprises a liquid storage tank and a processing table, a cross beam is arranged on the processing table, a first motor is installed at the center of the cross beam, the output end of the first motor is in transmission connection with a cross support, a processing assembly is arranged at the bottom end of the cross support, the processing assembly comprises a first linkage shaft, a first mounting table is sleeved on the first linkage shaft, an electric turntable is arranged on the first mounting table, a first electric push rod is installed at the center of the electric turntable, the output end of the first electric push rod is fixedly connected with a grinding mechanism, the cross support is driven to rotate by the first motor, the processing assembly is shifted to the side close to the single crystal silicon wafer, and the single crystal silicon wafer is subjected to progressive spiral grinding processing of a preset thickness value by cooperation of the grinding mechanism and the electric turntable.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of single crystal silicon wafer processing, and particularly relates to a progressive single crystal silicon wafer grinding device and a processing method thereof. BACKGROUND

[0002] Single crystal silicon wafers need to be treated by grinding equipment in processing to make the thickness and flatness of the wafers meet the requirements. In the grinding process of the traditional single crystal silicon wafer grinding device, the position of the grinding head is often kept unchanged, so the size of the single crystal silicon wafer that can be polished is relatively limited, and the thickness and flatness of the surface of the single crystal silicon wafer can meet the requirements only by clamping the single crystal silicon wafer for multiple times when polishing single crystal silicon wafers of different sizes, which is inconvenient to operate.

[0003] After retrieval, it is found that the authorized patent publication No. CN207858577U discloses a single crystal silicon wafer grinding device, which is published on September 14, 2018, and comprises a fixed clamp, a polishing disc, an infrared emitter, a clamping suction disc, a hydraulic telescopic rod, a hydraulic cylinder, a negative pressure device, a motor, a work platform, an infrared receiver and a controller. Four supporting rods are installed at the four corners of the top end of the fixed base, and the work platform is installed between the top ends of the supporting rods. The negative pressure device is installed at the middle position of the top end of the fixed base, and the motor box is installed at the middle position of one side of the top end of the fixed base. The bottom end of the inside of the motor box is provided with the motor. The motor, the driving wheel, the driving shaft, the driven wheel, the connecting belt and the polishing disc are installed, the motor drives the driving shaft and the driving wheel to rotate in use, the driving wheel drives the driven wheel, the driven shaft and the polishing disc to rotate through the connecting belt, and the single crystal silicon wafer is polished, which is fast and convenient to operate.

[0004] However, the device still has the following defects: although the polishing disc can rotate to polish the single crystal silicon wafer, the position of the polishing end face remains unchanged during polishing, so the size of the single crystal silicon wafer that can be polished is relatively limited, and it is inconvenient to polish the single crystal silicon wafer that exceeds the size of the polishing disc end face, which reduces the universality of the device. SUMMARY

[0005] In view of the above problems, the application provides a progressive single crystal silicon wafer grinding device and a processing method thereof, which comprises a liquid storage tank and a processing table.

[0006] The output end of the first motor is drivingly connected with a cross bracket, and the bottom end of the cross bracket is provided with a processing assembly.

[0007] A bearing table is arranged on the processing table, and a single crystal silicon wafer is adsorbed on the bearing table.

[0008] The processing assembly comprises a first linkage shaft, a first mounting table is sleeved on the first linkage shaft, an electric turntable is arranged on the first mounting table, a first electric push rod is installed at the center of the electric turntable, and a grinding mechanism is fixedly connected to the output end of the first electric push rod;

[0009] The cross support is driven to rotate by the first motor, so that the processing assembly is transferred to the side close to the single crystal silicon wafer, and the single crystal silicon wafer is subjected to progressive spiral grinding processing of a preset thickness value by cooperation of the grinding mechanism and the electric turntable.

[0010] Further, a material replacing table is arranged on one side of the processing table, an annular groove is formed in the processing table, an external gear ring is arranged on the processing table, and the bearing table is arranged in the external gear ring.

[0011] Further, a groove is formed in the bearing table, a plurality of groups of adsorption holes are formed in the inner wall of the groove, the plurality of groups of adsorption holes are in communication with the internal cavity of the bearing table, a plurality of groups of liquid jet nozzles are arranged on the inner wall of the bearing table, and the liquid jet directions of the plurality of groups of liquid jet nozzles are all towards the surface of the single crystal silicon wafer.

[0012] Further, a chip leakage groove is formed in the inner wall bottom end of the bearing table, the chip leakage groove is in communication with the interior of the liquid storage tank, a vacuum pump is arranged on one side of the bearing table, the air inlet end of the vacuum pump is communicated with an air suction pipe, the air suction pipe is in communication with the internal cavity of the bearing table, a liquid pump is arranged on one side of the bearing table, the liquid outlet end of the liquid pump is communicated with a liquid outlet pipe, and the liquid outlet pipe is in communication with the liquid inlet end of the plurality of groups of liquid jet nozzles.

[0013] Further, the first linkage shaft is rotationally connected to the bottom end of the cross support, a first gear is arranged on the first linkage shaft, the grinding mechanism comprises a limiting block, a screw rod groove is formed in the limiting block, a screw rod is rotationally connected in the screw rod groove, a second motor is arranged on one side of the limiting block, the output end of the second motor is in transmission connection with one end of the screw rod, an inner threaded block is threadedly connected to the screw rod, a third motor is arranged on the inner threaded block, and the output end of the third motor is in transmission connection with a grinding disc.

[0014] Further, a sliding groove is formed in the limiting block, a second electric push rod is arranged at the top end of the inner threaded block, the second electric push rod is movably attached to the sliding groove, and a distance sensor is fixedly connected to the output end of the second electric push rod.

[0015] Further, the bottom end of the cross-shaped support is also provided with a cleaning mechanism and a material changing mechanism, the cleaning mechanism comprises a second linkage shaft, a second gear is arranged on the second linkage shaft, a second mounting table is sleeved on the second linkage shaft, a third electric push rod is arranged on the second mounting table, a fourth motor is fixedly connected to the output end of the third electric push rod, and a soft brush is drivingly connected to the output end of the fourth motor.

[0016] Further, the material changing mechanism comprises a third linkage shaft, a third gear is arranged on the third linkage shaft, a third mounting table is sleeved on the third linkage shaft, a fourth electric push rod is arranged on the third mounting table, and a vacuum chuck is fixedly connected to the output end of the fourth electric push rod.

[0017] Further, a pull-out drawer is movably clamped in the liquid storage tank, a filter screen is arranged at the bottom end of the pull-out drawer, a chip guide groove is formed in the processing table and is arranged directly below the chip leakage groove, the chip guide groove and the inside of the liquid storage tank are in communication with each other, and a liquid taking pipe is arranged in the liquid storage tank and is in communication with the liquid inlet end of the liquid pump.

[0018] A processing method of a progressive single crystal silicon wafer grinding device, the processing method comprises:

[0019] The vacuum pump is started, the single crystal silicon wafer and the carrier plate are adsorbed to the bearing table, and the loading of the single crystal silicon wafer is completed;

[0020] The first motor is started, the processing assembly is moved to the side close to the single crystal silicon wafer, the first electric push rod is started to drive the grinding mechanism to move, and the grinding mechanism is moved to the surface of the single crystal silicon wafer;

[0021] The electric turntable is started, and the grinding mechanism performs progressive spiral grinding operation on the single crystal silicon wafer;

[0022] After the grinding operation on the single crystal silicon wafer is completed, the grinding mechanism monitors the distance of different positions on the surface of the single crystal silicon wafer;

[0023] The monitoring data is analyzed to judge the flatness of the surface of the single crystal silicon wafer, and the position and distance of the grinding mechanism are adjusted according to the data to perform secondary processing until the thickness and flatness of the single crystal silicon wafer meet the standard requirements.

[0024] The beneficial effects of the present application are:

[0025] 1. The second motor drives the screw rod to rotate, the inner threaded block drives the third motor and the grinding disc to move horizontally, the electric turntable drives the grinding mechanism to rotate, the grinding disc performs progressive spiral grinding on the single crystal silicon wafer, the moving distance of the inner threaded block is controlled, the grinding operation on single crystal silicon wafers of different sizes can be realized, the cutting surface of grinding is kept flat, and the universality of the device is effectively improved.

[0026] 2, The distance sensor is driven to move upward by the second electric push rod, so that the distance sensor monitors the surface distance of the monocrystalline silicon wafer; meanwhile, the distance sensor is driven to move horizontally by the second motor driving the screw rod, so that the distance sensor can monitor the distance of different positions on the surface of the monocrystalline silicon wafer; when the cut surface of the monocrystalline silicon wafer is uneven, the position of the grinding disc can be adjusted according to the distance measurement data, and the surface of the monocrystalline silicon wafer is processed again, thereby effectively improving the yield of the monocrystalline silicon wafer grinding process.

[0027] 3, The processing assembly, the cleaning mechanism and the material changing mechanism are driven to move synchronously by the first motor driving the cross support to rotate, and the positions of the processing assembly, the cleaning mechanism and the material changing mechanism are transferred while the processing assembly, the cleaning mechanism and the material changing mechanism are simultaneously self-rotated by the meshing action between the first gear, the second gear, the third gear and the outer gear ring, so that when the processing assembly, the cleaning mechanism and the material changing mechanism are transferred to the side close to the monocrystalline silicon wafer, the processing tool faces inward to the monocrystalline silicon wafer, which is convenient for processing; when the processing assembly, the cleaning mechanism and the material changing mechanism are transferred to the side close to the material changing table, the processing tool faces outward to the material changing table, which is convenient for changing the material of the monocrystalline silicon wafer and also convenient for repairing and replacing the processing tool.

[0028] 4, The grinding liquid in the liquid storage tank is pumped out by the liquid pump and sprayed to the surface of the monocrystalline silicon wafer through a plurality of groups of liquid nozzles, which effectively avoids the splashing of debris generated during grinding and avoids the damage to the monocrystalline silicon wafer caused by the heat generated during processing. After processing is completed, the surface of the monocrystalline silicon wafer is washed by the grinding liquid to avoid the residue of debris on the surface of the monocrystalline silicon wafer. The debris after washing and the grinding liquid are discharged to the liquid storage tank through the debris leakage groove for filtering and collecting the debris and recycling the grinding liquid, which effectively avoids environmental pollution and saves processing cost. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0030] Figure 1 A schematic diagram of the main structure according to an embodiment of the present application is shown;

[0031] Figure 2 A schematic diagram of the upper part of the processing table according to an embodiment of the present application is shown;

[0032] Figure 3A schematic view of a bearing table structure according to an embodiment of the present application is shown.

[0033] Figure 4 A schematic view of a machining assembly structure according to an embodiment of the present application is shown.

[0034] Figure 5 A schematic view of a grinding mechanism structure according to an embodiment of the present application is shown.

[0035] Figure 6 A schematic view of a cleaning mechanism structure according to an embodiment of the present application is shown.

[0036] Figure 7 A schematic view of a material changing mechanism structure according to an embodiment of the present application is shown.

[0037] Figure 8 A cross-sectional view of an internal structure of a liquid storage tank according to an embodiment of the present application is shown.

[0038] In the figure: 1, liquid storage tank; 101, pull-out drawer; 102, filter screen; 103, liquid taking pipe; 2, machining table; 201, annular groove; 202, chip guide groove; 3, material changing table; 4, fixed block; 5, support column; 6, cross beam; 7, first motor; 8, cross support; 9, machining assembly; 901, first linkage shaft; 902, first gear; 903, first mounting table; 904, electric turntable; 905, first electric push rod; 906, grinding mechanism; 9061, limiting block; 9062, screw rod groove; 9063, screw rod; 9064, second motor; 9065, internally threaded block; 9066, third motor; 9067, grinding disc; 9068, sliding groove; 9069, second electric push rod; 90610, distance sensor; 10, cleaning mechanism; 1001, second linkage shaft; 1002, second gear; 1003, second mounting table; 1004, third electric push rod; 1005, fourth motor; 1006, soft-bristled brush; 11, material changing mechanism; 1101, third linkage shaft; 1102, third gear; 1103, third mounting table; 1104, fourth electric push rod; 1105, vacuum chuck; 12, bearing table; 1201, groove; 1202, adsorption hole; 1203, liquid spraying nozzle; 1204, chip leakage groove; 13, outer gear ring; 14, slide plate; 15, single crystal silicon wafer; 16, vacuum pump; 1601, air suction pipe; 17, liquid pump; 1701, liquid outlet pipe. DETAILED DESCRIPTION

[0039] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0040] The embodiment of the present application provides a progressive single crystal silicon wafer grinding device, which comprises a liquid storage tank 1 and a processing table 2. Figure 1 As shown in the figure.

[0041] The liquid storage tank 1 stores grinding fluid, the processing table 2 is arranged on the liquid storage tank 1, one side of the processing table 2 is provided with a material changing table 3, two groups of fixing blocks 4 are symmetrically arranged on the side wall of the processing table 2, support columns 5 are fixedly connected to the two groups of fixing blocks 4, cross beams 6 are fixedly connected to the top ends of the two groups of support columns 5, a first motor 7 is installed at the center of the cross beam 6, a cross support 8 is drivingly connected to the output end of the first motor 7, a processing assembly 9, a cleaning mechanism 10 and a material changing mechanism 11 are arranged at the bottom end of the cross support 8, and the processing assembly 9, the cleaning mechanism 10 and the material changing mechanism 11 are movably attached to the processing table 2.

[0042] As shown in the figure. Figure 2 and Figure 3 As shown in the figure.

[0043] An annular groove 201 is formed in the processing table 2, an outer gear ring 13 is arranged on the processing table 2, a bearing table 12 is arranged in the outer gear ring 13, a carrier plate 14 is adsorbed on the bearing table 12, and a single crystal silicon wafer 15 is bonded to the carrier plate 14.

[0044] A groove 1201 is formed in the bearing table 12, the groove 1201 is attached to the carrier plate 14, a plurality of groups of adsorption holes 1202 are formed in the inner wall of the groove 1201, the plurality of groups of adsorption holes 1202 are in communication with the internal cavity of the bearing table 12, a plurality of groups of liquid injection nozzles 1203 are arranged on the inner wall of the bearing table 12, the liquid injection directions of the plurality of groups of liquid injection nozzles 1203 are all towards the surface of the single crystal silicon wafer 15, a debris leakage groove 1204 is formed at the bottom end of the inner wall of the bearing table 12, the debris leakage groove 1204 is in communication with the interior of the liquid storage tank 1, a vacuum pump 16 is arranged on one side of the bearing table 12, an air suction pipe 1601 is in communication with the air inlet end of the vacuum pump 16, the air suction pipe 1601 is in communication with the internal cavity of the bearing table 12, a liquid pump 17 is arranged on one side of the bearing table 12, a liquid outlet pipe 1701 is in communication with the liquid outlet end of the liquid pump 17, and the liquid outlet pipe 1701 is in communication with the liquid inlet end of the plurality of groups of liquid injection nozzles 1203.

[0045] Specifically, the interior of the bearing table 12 is formed into a vacuum by the vacuum pump 16, so that the surface of the plurality of groups of adsorption holes 1202 is formed into a negative pressure, the slide plate 14 is adsorbed, the adsorption force is effectively improved by covering all the adsorption holes 1202 by the slide plate 14, and the slide plate 14 is attached in the groove 1201, so that the monocrystalline silicon wafer 15 attached on the slide plate 14 is more stable during grinding processing, and displacement of the monocrystalline silicon wafer 15 is avoided to affect the processing precision.

[0046] Further, the grinding liquid in the liquid storage tank 1 is pumped out by the liquid pump 17 and sprayed to the surface of the monocrystalline silicon wafer 15 through the plurality of groups of liquid nozzles 1203, so as to effectively avoid the splashing of the debris generated during grinding processing, avoid the damage of the heat generated by friction during processing to the monocrystalline silicon wafer 15, and rinse the surface of the monocrystalline silicon wafer 15 after processing, so as to avoid the residual debris on the surface of the monocrystalline silicon wafer, and the rinsed debris and the grinding liquid are discharged to the liquid storage tank 1 through the debris discharge groove 1204 for centralized treatment.

[0047] The processing assembly 9 comprises a first linkage shaft 901. Figure 4 and Figure 5 as shown.

[0048] The first linkage shaft 901 is rotationally connected at the bottom end of the cross bracket 8, the bottom end of the first linkage shaft 901 is movably attached to the annular groove 201, a first gear 902 is arranged on the first linkage shaft 901, the first gear 902 is in meshing connection with the outer gear ring 13, a first mounting table 903 is sleeved on the first linkage shaft 901, an electric turntable 904 is arranged on the first mounting table 903, a first electric push rod 905 is installed at the center of the electric turntable 904, and a grinding mechanism 906 is fixedly connected to the output end of the first electric push rod 905;

[0049] The grinding mechanism 906 comprises a limiting block 9061, a screw rod groove 9062 is formed in the limiting block 9061, a screw rod 9063 is rotationally connected in the screw rod groove 9062, a second motor 9064 is arranged on one side of the outer wall of the limiting block 9061, the output end of the second motor 9064 is in transmission connection with one end of the screw rod 9063, an inner threaded block 9065 is threadedly connected on the screw rod 9063, a third motor 9066 is arranged on the inner threaded block 9065, a grinding disc 9067 is in transmission connection with the output end of the third motor 9066, a sliding groove 9068 is formed in the limiting block 9061, a second electric push rod 9069 is arranged at the top end of the inner threaded block 9065, the second electric push rod 9069 is movably attached to the sliding groove 9068, and a distance sensor 90610 is fixedly connected to the output end of the second electric push rod 9069;

[0050] Specifically, the cross slide 8 is driven to rotate by the first motor 7, so that the machining assembly 9 moves synchronously. The first gear 902 is driven to rotate by the meshing with the outer gear ring 13, so that the first gear 902 rotates while moving. When the machining assembly 9 moves to the side close to the single crystal silicon wafer 15, the grinding disc 9067 faces the surface of the single crystal silicon wafer 15, so as to facilitate the grinding of the single crystal silicon wafer 15. When the machining assembly 9 moves to the side close to the material changing table 3, the grinding disc 9067 faces away from the single crystal silicon wafer 15, so as to facilitate the maintenance or replacement of the grinding disc 9067. When the machining assembly 9 moves to the side close to the single crystal silicon wafer 15, the grinding mechanism 906 is driven to move by the first electric push rod 905, so that the grinding disc 9067 moves to the surface of the single crystal silicon wafer 15. The grinding disc 9067 is driven to rotate by the third motor 9066, so as to grind the surface of the single crystal silicon wafer 15. The distance sensor 90610 is driven to move upward by the second electric push rod 9069, so as to monitor the distance of the surface of the single crystal silicon wafer 15. When the grinding thickness of the grinding disc 9067 meets the preset value, the first electric push rod 905 is turned off, so that the grinding depth of the grinding disc 9067 remains unchanged. The third motor 9066 and the grinding disc 9067 are driven to move horizontally by the inner threaded block 9065, which is driven to rotate by the lead screw 9063 driven by the second motor 9064. The electric turntable 904 drives the grinding mechanism 906 to rotate, so that the grinding disc 9067 performs progressive spiral grinding on the single crystal silicon wafer 15. By controlling the moving distance of the inner threaded block 9065, the grinding operation on single crystal silicon wafers 15 of different sizes can be realized, and the grinding surface remains flat.

[0051] Further, after the grinding operation on the single crystal silicon wafer 15 is completed, the third motor 9066 is turned off. The distance sensor 90610 is driven to move upward by the second electric push rod 9069, so as to monitor the distance of the surface of the single crystal silicon wafer 15. The distance sensor 90610 is driven to move horizontally by the inner threaded block 9065, which is driven to rotate by the lead screw 9063 driven by the second motor 9064. The electric turntable 904 drives the grinding mechanism 906 to rotate, so that the distance sensor 90610 can monitor the distance of different positions on the surface of the single crystal silicon wafer 15. When the surface of the single crystal silicon wafer 15 is not flat, the position of the grinding disc 9067 can be adjusted according to the distance measurement data, and the surface of the single crystal silicon wafer 15 can be processed again, so as to improve the yield of the grinding operation on the single crystal silicon wafer 15. When the single crystal silicon wafer 15 is being ground, the distance sensor 90610 can be moved downward by the second electric push rod 9069, so as to be shielded by the grinding disc 9067, avoiding damage to the distance sensor 90610 caused by the debris generated by the grinding operation.

[0052] The cleaning mechanism 10 comprises a second linkage shaft 1001; as shown in the example, Figure 6

[0053] The second linkage shaft 1001 is rotatably connected to the bottom end of the cross bracket 8, the bottom end of the second linkage shaft 1001 is movably attached to the annular groove 201, a second gear 1002 is arranged on the second linkage shaft 1001, the second gear 1002 is meshingly connected with the outer gear ring 13, a second mounting table 1003 is sleeved on the second linkage shaft 1001, a third electric push rod 1004 is arranged on the second mounting table 1003, a fourth motor 1005 is fixedly connected to the output end of the third electric push rod 1004, and a soft brush 1006 is drivingly connected to the output end of the fourth motor 1005;

[0054] Specifically, the cross bracket 8 is driven to rotate by the first motor 7, so that the cleaning mechanism 10 moves synchronously, the second gear 1002 is driven to rotate by the meshing action of the second gear 1002 and the outer gear ring 13, so that the second gear 1002 rotates while moving, when the cleaning mechanism 10 moves to the side close to the single crystal silicon wafer 15, the soft brush 1006 faces the surface of the single crystal silicon wafer 15, the soft brush 1006 is driven to move to the surface of the single crystal silicon wafer 15 by the third electric push rod 1004, the soft brush 1006 is driven to rotate by the fourth motor 1005, the surface of the single crystal silicon wafer 15 is cleaned, and the cleanliness of the surface of the single crystal silicon wafer 15 is improved, and when the cleaning mechanism 10 moves to the side close to the material changing table 3, the soft brush 1006 faces away from the single crystal silicon wafer 15, so as to facilitate the maintenance or replacement of the soft brush 1006.

[0055] The material changing mechanism 11 comprises a third linkage shaft 1101; as shown in the example, Figure 7

[0056] The third linkage shaft 1101 is rotatably connected to the bottom end of the cross bracket 8, the bottom end of the third linkage shaft 1101 is movably attached to the annular groove 201, a third gear 1102 is arranged on the third linkage shaft 1101, the third gear 1102 is meshingly connected with the outer gear ring 13, a third mounting table 1103 is sleeved on the third linkage shaft 1101, a fourth electric push rod 1104 is arranged on the third mounting table 1103, and a vacuum chuck 1105 is fixedly connected to the output end of the fourth electric push rod 1104;

[0057] ​​Specifically, the cross bracket 8 is driven to rotate by the first motor 7, so that the material changing mechanism 11 moves synchronously, and the third gear 1102 is driven to rotate by the meshing of the outer gear ring 13, so that the third gear 1102 rotates while moving, when the material changing mechanism 11 moves to the side close to the single crystal silicon wafer 15, the vacuum chuck 1105 faces the surface of the single crystal silicon wafer 15, the fourth electric push rod 1104 drives the vacuum chuck 1105 to move to the surface of the single crystal silicon wafer 15, and the single crystal silicon wafer 15 is adsorbed, and at the same time, the vacuum pump 16 is closed, so that the vacuum chuck 1105 drives the processed single crystal silicon wafer 15 to be transferred, when the material changing mechanism 11 moves to the side close to the material changing table 3, the vacuum chuck 1105 drives the processed single crystal silicon wafer 15 to face the outer side of the material changing table 3, so as to facilitate taking down the processed single crystal silicon wafer 15, and the next group of single crystal silicon wafers 15 to be processed are adsorbed on the vacuum chuck 1105, and are transferred by the vacuum chuck 1105 and are transferred to the bearing table 12 to wait for processing.

[0058] As shown in the examples. Figure 8 As shown in the examples.

[0059] The pull-out drawer 101 is movably clamped in the liquid storage tank 1, the bottom end of the pull-out drawer 101 is provided with a filter screen 102, the machining table 2 is provided with a chip guide groove 202, the chip guide groove 202 is arranged directly below the chip leakage groove 1204, and the chip guide groove 202 and the inside of the liquid storage tank 1 are in communication with each other, the liquid storage tank 1 is provided with a liquid taking pipe 103, and the liquid taking pipe 103 and the liquid inlet end of the liquid pump 17 are in communication with each other.

[0060] Specifically, the chips generated by grinding and the grinding fluid enter the pull-out drawer 101 through the chip leakage groove 1204 and the chip guide groove 202, and the chips and the grinding fluid are filtered by the filter screen 102, so that the chips are retained in the pull-out drawer 101 for centralized treatment, and the filtered grinding fluid is recycled in the liquid storage tank 1.

[0061] The working principle of the progressive single crystal silicon wafer grinding device provided by the application is as follows:

[0062] The cross support 8 is driven to rotate by the first motor 7, so that the material changing mechanism 11 moves synchronously. The third gear 1102 rotates while moving by the meshing with the outer gear ring 13. When the material changing mechanism 11 moves to the side close to the single crystal silicon wafer 15, the vacuum chuck 1105 faces the surface of the single crystal silicon wafer 15. The fourth electric push rod 1104 drives the vacuum chuck 1105 to move to adhere to the surface of the single crystal silicon wafer 15, so that the single crystal silicon wafer 15 is adsorbed. At the same time, the vacuum pump 16 is closed, so that the vacuum chuck 1105 drives the processed single crystal silicon wafer 15 to be transferred. When the material changing mechanism 11 moves to the side close to the material changing table 3, the vacuum chuck 1105 drives the processed single crystal silicon wafer 15 to face the outer side of the material changing table 3, so that the processed single crystal silicon wafer 15 is taken down. The next group of single crystal silicon wafers 15 to be processed is adsorbed on the vacuum chuck 1105, and is transferred to the bearing table 12 to wait for processing.

[0063] The vacuum pump 16 forms a vacuum inside the bearing table 12, so that the surface of the plurality of adsorption holes 1202 forms a negative pressure, and the slide plate 14 is adsorbed. The slide plate 14 covers all the adsorption holes 1202, effectively improves the adsorption force, and the slide plate 14 is adhered in the groove 1201, so that the single crystal silicon wafer 15 adhered on the slide plate 14 is more stable during grinding processing, and displacement of the single crystal silicon wafer 15 is avoided to affect the processing precision.

[0064] The first motor 7 drives the cross bracket 8 to rotate, and the machining assembly 9 moves synchronously. Through the meshing action of the first gear 902 and the outer tooth ring 13, the first gear 902 rotates while moving, so that the machining assembly 9 moves to the side close to the single crystal silicon wafer 15, and the grinding disc 9067 faces the surface of the single crystal silicon wafer 15, facilitating the grinding of the single crystal silicon wafer 15. When the machining assembly 9 moves to the side close to the material changing table 3, the grinding disc 9067 faces away from the single crystal silicon wafer 15, so as to facilitate the maintenance or replacement of the grinding disc 9067. When the machining assembly 9 moves to the side close to the single crystal silicon wafer 15, the first electric push rod 905 drives the grinding mechanism 906 to move, so that the grinding disc 9067 moves to the surface of the single crystal silicon wafer 15. The third motor 9066 drives the grinding disc 9067 to rotate, and the surface of the single crystal silicon wafer 15 is ground. The second electric push rod 9069 drives the distance sensor 90610 to move upward, so that the distance sensor 90610 can monitor the distance of the surface of the single crystal silicon wafer 15. When the grinding thickness of the grinding disc 9067 meets the preset value, the first electric push rod 905 is closed, so that the grinding depth of the grinding disc 9067 remains unchanged. The second motor 9064 drives the screw rod 9063 to rotate, so that the inner threaded block 9065 drives the third motor 9066 and the grinding disc 9067 to move horizontally. At the same time, the electric turntable 904 drives the grinding mechanism 906 to rotate, so that the grinding disc 9067 performs progressive spiral grinding on the single crystal silicon wafer 15. By controlling the movement distance of the inner threaded block 9065, grinding operation can be performed on single crystal silicon wafers 15 of different sizes, and the grinding surface remains flat.

[0065] The liquid pump 17 pumps the grinding liquid in the liquid storage tank 1 out and sprays it out to the surface of the single crystal silicon wafer 15 through a plurality of groups of liquid nozzles 1203, effectively avoiding the splashing of debris generated during grinding and avoiding damage to the single crystal silicon wafer 15 caused by heat generated during processing. After processing, the surface of the single crystal silicon wafer 15 is washed by the grinding liquid to avoid the residue of debris on the surface of the single crystal silicon wafer. The debris after washing and the grinding liquid are discharged to the liquid storage tank 1 through the debris discharge groove 1204 for centralized treatment.

[0066] After the grinding operation of the single crystal silicon wafer 15 is completed, the third motor 9066 is turned off, the distance sensor 90610 is driven to move upward by the second electric push rod 9069, the distance sensor 90610 monitors the surface distance of the single crystal silicon wafer 15, the inner threaded block 9065 drives the distance sensor 90610 to move horizontally by driving the lead screw 9063 by the second motor 9064, and the distance sensor 90610 can monitor the distance of different positions on the surface of the single crystal silicon wafer 15 by driving the grinding mechanism 906 to rotate by the electric turntable 904. When the cut surface of the single crystal silicon wafer 15 is uneven, the position of the grinding disc 9067 can be adjusted according to the distance measurement data, and the surface of the single crystal silicon wafer 15 can be processed again to improve the yield of the single crystal silicon wafer 15 grinding process. When the single crystal silicon wafer 15 is ground, the distance sensor 90610 can be driven to move downward by the second electric push rod 9069, so that the grinding disc 9067 shields it to avoid damage to the distance sensor 90610 caused by the debris generated during grinding.

[0067] The cleaning mechanism 10 is driven to move synchronously by the first motor 7 driving the cross bracket 8 to rotate, the second gear 1002 is driven to rotate while moving by the meshing action of the second gear 1002 and the outer gear ring 13, the cleaning mechanism 10 is moved to the side close to the single crystal silicon wafer 15, the soft brush 1006 faces the surface of the single crystal silicon wafer 15, the soft brush 1006 is driven to move to adhere to the surface of the single crystal silicon wafer 15 by the third electric push rod 1004, and the soft brush 1006 is driven to rotate by the fourth motor 1005 to clean the surface of the single crystal silicon wafer 15 and improve the cleanliness of the surface of the single crystal silicon wafer 15. When the cleaning mechanism 10 moves to the side close to the material changing table 3, the soft brush 1006 faces away from the single crystal silicon wafer 15, so as to facilitate maintenance or replacement of the soft brush 1006.

[0068] The debris generated during grinding and the grinding fluid enter the pull-out drawer 101 through the debris leakage groove 1204 and the debris guide groove 202, and the debris and the grinding fluid are filtered by the filter screen 102, so that the debris is retained in the pull-out drawer 101 for centralized treatment, and the filtered grinding fluid is recycled in the liquid storage tank 1.

[0069] On the basis of the above-mentioned progressive single crystal silicon wafer grinding device, the embodiment of the present application also proposes a processing method for the grinding device. Illustratively, the processing method comprises:

[0070] The single crystal silicon wafer to be processed is bonded to the center of the carrier plate, the vacuum chuck is turned on, and the single crystal silicon wafer and the carrier plate are adsorbed to the vacuum chuck;

[0071] The first motor is started, the vacuum chuck drives the single crystal silicon wafer to move and rotate at the same time, when the vacuum chuck rotates to the side of the supporting table, the wafer plate is just rotated to the side facing the supporting table;

[0072] The fourth electric push rod is started to make the vacuum chuck drive the single crystal silicon wafer and the wafer plate to move into the groove, the vacuum pump is started to make the adsorption hole adsorb the wafer plate, the vacuum chuck is closed to separate from the single crystal silicon wafer, and the fourth electric push rod drives the vacuum chuck to reset, so that the loading of the single crystal silicon wafer is completed;

[0073] The first motor is started to make the processing assembly move to the side close to the single crystal silicon wafer, the first electric push rod is started to drive the grinding mechanism to move, so that the grinding disc moves to the surface of the single crystal silicon wafer;

[0074] The second motor and the third motor and the electric turntable are started, so that the grinding disc performs progressive spiral grinding operation on the single crystal silicon wafer;

[0075] The liquid pump is started to pump out the grinding liquid in the liquid storage tank and spray it out to the surface of the single crystal silicon wafer through a plurality of groups of liquid nozzles;

[0076] After the grinding operation on the single crystal silicon wafer is completed, the third motor is closed, the second electric push rod is started, the distance sensor moves upward and is started, the second motor and the electric turntable are started, and the distance sensor monitors the distance of different positions on the surface of the single crystal silicon wafer;

[0077] The monitoring data of the distance sensor is analyzed to judge the flatness of the surface of the single crystal silicon wafer, and the position and distance of the grinding disc are adjusted according to the data for secondary processing until the thickness and flatness of the single crystal silicon wafer meet the standard requirements;

[0078] The first motor is started to make the cleaning mechanism move to the side close to the single crystal silicon wafer to clean the residual debris on the surface of the single crystal silicon wafer, and the material changing mechanism moves to the side close to the material changing table to perform material changing operation.

[0079] Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalent ones; and these modifications or replacements 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 application.

Claims

1. A progressive single crystal silicon wafer grinding device, comprising a liquid storage tank (1) and a processing table (2), characterized in that: The machining table (2) is provided with a cross beam (6), and a first motor (7) is installed at the center of the cross beam (6); The output end of the first motor (7) is drivingly connected with a cross support (8), and the bottom end of the cross support (8) is provided with a machining assembly (9); The machining table (2) is provided with a bearing table (12), and a single crystal silicon wafer (15) is adsorbed on the bearing table (12); The machining assembly (9) comprises a first linkage shaft (901), a first mounting table (903) is sleeved on the first linkage shaft (901), an electric turntable (904) is arranged on the first mounting table (903), a first electric push rod (905) is installed at the center of the electric turntable (904), and a grinding mechanism (906) is fixedly connected to the output end of the first electric push rod (905); The first motor (7) drives the cross support (8) to rotate, so that the machining assembly (9) is shifted to the side close to the single crystal silicon wafer (15), and the grinding mechanism (906) cooperates with the electric turntable (904) to perform progressive spiral grinding processing on the single crystal silicon wafer (15) with a preset thickness value; The first linkage shaft (901) is rotatably connected to the bottom end of the cross support (8), a first gear (902) is arranged on the first linkage shaft (901), the grinding mechanism (906) comprises a limiting block (9061), a screw rod groove (9062) is formed in the limiting block (9061), a screw rod (9063) is rotatably connected in the screw rod groove (9062), a second motor (9064) is arranged on one side of the outer wall of the limiting block (9061), the output end of the second motor (9064) is drivingly connected with one end of the screw rod (9063), an internally-threaded block (9065) is threadedly connected on the screw rod (9063), a third motor (9066) is arranged on the internally-threaded block (9065), and the output end of the third motor (9066) is drivingly connected with a grinding disc (9067); The bottom end of the cross support (8) is further provided with a cleaning mechanism (10) and a material replacing mechanism (11), the cleaning mechanism (10) comprises a second linkage shaft (1001), a second gear (1002) is arranged on the second linkage shaft (1001), a second mounting table (1003) is sleeved on the second linkage shaft (1001), a third electric push rod (1004) is arranged on the second mounting table (1003), a fourth motor (1005) is fixedly connected to the output end of the third electric push rod (1004), and the output end of the fourth motor (1005) is drivingly connected with a soft brush (1006); The material replacing mechanism (11) comprises a third linkage shaft (1101), a third gear (1102) is arranged on the third linkage shaft (1101), a third mounting table (1103) is sleeved on the third linkage shaft (1101), a fourth electric push rod (1104) is arranged on the third mounting table (1103), and a vacuum chuck (1105) is fixedly connected to the output end of the fourth electric push rod (1104).

2. The apparatus for progressive single crystal silicon wafer grinding according to claim 1, wherein: The processing table (2) is provided with a material changing table (3) on one side, the processing table (2) is provided with an annular groove (201), the processing table (2) is provided with an external gear ring (13), and the bearing table (12) is arranged in the external gear ring (13).

3. The apparatus according to claim 2, wherein: The bearing table (12) is provided with a groove (1201), the inner wall of the groove (1201) is provided with a plurality of groups of adsorption holes (1202), the plurality of groups of adsorption holes (1202) are in communication with the internal cavity of the bearing table (12), and the inner wall of the bearing table (12) is provided with a plurality of groups of liquid injection nozzles (1203).

4. The apparatus for progressive single crystal silicon wafer grinding according to claim 3, wherein: The inner wall bottom end of the bearing table (12) is provided with a chip leakage groove (1204), the chip leakage groove (1204) is in communication with the inside of the liquid storage tank (1), one side of the bearing table (12) is provided with a vacuum pump (16), the air inlet end of the vacuum pump (16) is communicated with a suction pipe (1601), the suction pipe (1601) is in communication with the internal cavity of the bearing table (12), one side of the bearing table (12) is provided with a liquid pump (17), the liquid outlet end of the liquid pump (17) is communicated with a liquid outlet pipe (1701), and the liquid outlet pipe (1701) is in communication with the liquid inlet end of the plurality of groups of liquid injection nozzles (1203).

5. The apparatus for progressive single crystal silicon wafer grinding according to claim 1, wherein: The limiting block (9061) is provided with a sliding groove (9068), the top end of the inner threaded block (9065) is provided with a second electric push rod (9069), the second electric push rod (9069) is movably attached to the sliding groove (9068), and the output end of the second electric push rod (9069) is fixedly connected with a distance sensor (90610).

6. The apparatus for progressive single crystal silicon wafer grinding according to claim 4, wherein: The liquid storage tank (1) is movably clamped with a drawer (101), the bottom end of the drawer (101) is provided with a filter screen (102), the processing table (2) is provided with a chip guide groove (202), the chip guide groove (202) is arranged directly below the chip leakage groove (1204), and the chip guide groove (202) is in communication with the inside of the liquid storage tank (1), and the liquid storage tank (1) is provided with a liquid taking pipe (103), and the liquid taking pipe (103) is in communication with the liquid inlet end of the liquid pump (17).

7. A processing method applied to the progressive single crystal silicon wafer grinding apparatus according to any one of claims 1 to 6, characterized by: The processing method comprises: Turning on the vacuum pump, adsorbing the single crystal silicon wafer and the carrier plate to the bearing table, and completing the loading of the single crystal silicon wafer; Turning on the first motor, moving the processing assembly to the side close to the single crystal silicon wafer, turning on the first electric push rod to drive the grinding mechanism to move, and moving the grinding mechanism to the surface of the single crystal silicon wafer; Turning on the electric turntable, and performing progressive spiral grinding operation on the single crystal silicon wafer by the grinding mechanism; After completing the grinding operation on the single crystal silicon wafer, the grinding mechanism monitors the distance of different positions on the surface of the single crystal silicon wafer; Analyzing the monitoring data to judge the flatness of the surface of the single crystal silicon wafer, and adjusting the position and distance of the grinding mechanism according to the data to perform secondary processing until the thickness and flatness of the single crystal silicon wafer meet the standard requirements.

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