JP5788304B2 - Grinding equipment - Google Patents

Description

  The present invention relates to a grinding apparatus capable of adjusting the inclination of a rotating shaft of a holding unit that holds a plate-shaped workpiece to be ground.

  In the grinding apparatus, the wafer is held on the chuck table, and the surface of the wafer is ground as the chuck table rotates and the rotating grindstone contacts the surface of the wafer. The holding surface of the chuck table is formed as a conical surface, and the rotating shaft of the grinding means is also inclined correspondingly (see, for example, Patent Document 1).

  The angle formed between the rotation axis of the chuck table and the rotation axis of the grinding means equipped with the grindstone is adjusted to a predetermined angle, and the wafer thickness distribution is obtained for the ground wafer, and the thickness distribution is obtained. Accordingly, the inclination of the rotation axis of the chuck table or the rotation axis of the grinding means is adjusted. As described above, the operation of adjusting the inclination of the rotating shaft of the grinding means or the chuck table is repeatedly performed based on the thickness distribution of the wafer (see, for example, Patent Document 2).

JP 2009-141176 A JP 2009-090389 A

  However, since the thickness distribution of the wafer after grinding is measured and the tilt of the rotation axis of the chuck table or the rotation axis of the grinding means is adjusted based on the result, grinding for adjustment is necessary and time is required. There is a problem that it takes too much.

  In addition, wafers ground before adjusting the tilt of the rotating shaft have thickness variations, and therefore cannot be shipped as products and are discarded. Therefore, there is also a problem that a lot of waste is generated on the wafer.

  The present invention has been considered in view of such circumstances, and it is an object of the present invention to efficiently adjust the inclination of the rotating shaft so as not to waste the wafer.

The present invention relates to a holding means capable of holding and rotating a plate-like work, a grinding means for grinding a plate-like work provided with an elevating mechanism and held by the holding means, and a thickness of the plate-like work held by the holding means. A holding device that holds one surface of the plate-like workpiece, a rotation axis that passes through the center of the holding surface, and an inclination of the rotation axis. A thickness adjusting means for measuring the thickness of the plate-like workpiece in a non-contact state at a plurality of locations from above the plate-like workpiece held on the holding surface, and a measurement in the measurement portion. A calculation unit that calculates the inclination of the rotation axis based on the value, and a control unit that receives the value of the inclination of the rotation axis calculated by the calculation unit and drives the inclination adjustment unit based on the value of the inclination , and the grinding unit includes , Board Pause the grinding before the workpiece reaches the thickness finish, measured the thickness of the plate-shaped workpiece by the thickness measuring means, based on the difference between the inclination value and the value of a predetermined inclination of the rotation axis calculated by the calculating section In addition, after the control unit corrects the inclination of the rotation axis by driving the inclination adjusting means , the plate-like workpiece is ground again until the predetermined finishing thickness is formed by the grinding means.

  The thickness in the radial direction of the plate-like workpiece can also be measured by scanning the measurement unit from the rotation center of the plate-like workpiece held by the holding means toward the outer peripheral end. In addition, the thickness of the workpiece is measured at three locations, that is, the rotation center of the plate-shaped workpiece held by the holding means, the outer peripheral end of the plate-shaped workpiece, and the midpoint between the rotation center of the plate-shaped workpiece and the outer peripheral end. May be measured.

  In the present invention, the grinding means temporarily stops grinding before the plate-like workpiece reaches the finished thickness, measures the thickness of the plate-like workpiece by the thickness measuring means, and based on the inclination of the rotation axis calculated by the calculation unit. After the inclination of the rotation axis is corrected by the inclination adjusting means, the plate-like work is ground until it is again formed to a predetermined finished thickness by the grinding means, so that a plate-like work having a thickness variation is not formed. All plate-like workpieces can be formed in a desired thickness without causing waste in the plate-like workpieces. Further, it is not necessary to perform grinding for adjusting the rotating shaft, and the plate-like workpiece can be finished to a predetermined thickness by adjusting the inclination of the rotating shaft by one grinding, which is efficient.

It is a perspective view which shows an example of a grinding device. It is sectional drawing which shows schematically the 1st example of a holding means, a grinding means, and a thickness measurement means. It is a side view which shows a holding means and an inclination adjustment means. It is an expanded sectional view which shows a holding means and an inclination adjustment means. It is explanatory drawing which shows the example of arrangement | positioning of the position adjustment unit which comprises an inclination adjustment means. It is a perspective view which shows a position adjustment unit, a holding means, and a drive mechanism of the holding means. It is sectional drawing which shows the example of a position adjustment unit. It is sectional drawing which shows schematically the positional relationship of a holding means and a 1st grinding means. It is sectional drawing which shows schematically the positional relationship of a holding means and a 2nd grinding means. It is sectional drawing which shows schematically the state which performs finish grinding. It is sectional drawing which shows the 1st example of the plate-shaped workpiece | work with thickness variation. It is sectional drawing which shows the 2nd example of the plate-shaped workpiece | work with thickness variation. It is sectional drawing which shows the 3rd example of the plate-shaped workpiece | work with thickness variation. It is sectional drawing which shows the 4th example of the plate-shaped workpiece | work with thickness variation. (A) is a perspective view showing a second example of the holding means, the grinding means, and the thickness measuring means, and (b) is a schematic view showing the second example of the holding means, the grinding means, and the thickness measuring means. It is sectional drawing.

  A grinding apparatus 1 shown in FIG. 1 is an apparatus for holding a plate-like workpiece (plate-like workpiece) by a plurality of holding means 2 and grinding the plate-like workpiece by the first grinding means 3a and the second grinding means 3b. It is.

  The grinding apparatus 1 includes an attachment / detachment area A where a plate-like workpiece is attached / detached to / from the holding means 2 and a processing area B where grinding is performed. The plurality of holding means 2 are supported by the turntable 2a so as to be able to rotate and revolve, and each holding means 2 revolves by the rotation of the turntable 2a, so that the space between the attachment / detachment area A and the processing area B is obtained. It is movable.

  The attachment / detachment area A includes a supply cassette 4a that stores a plate-shaped workpiece before grinding and a recovery cassette 4b that stores a plate-shaped workpiece after grinding. In addition, a transfer robot 5 for carrying out the workpiece from the supply cassette 4a and carrying the workpiece into the collection cassette 4b is disposed at a position facing the supply cassette 4a and the recovery cassette 4b.

  In the movable range of the transfer robot 5, a temporary placement means 6 for temporarily placing a workpiece before processing and a cleaning means 7 for cleaning grinding waste adhering to the workpiece after processing are disposed.

  In the vicinity of the temporary placement means 6, a first transport means 8 a for transporting the plate-shaped workpiece temporarily placed on the temporary placement means 6 to the holding means 2 located in the attachment / detachment area A is disposed. Further, in the vicinity of the cleaning unit 7, a second transport unit 8 b that transports the plate work after grinding held by the holding unit 2 located in the attachment / detachment area A to the cleaning unit 7 is disposed.

  In the processing area B, a first grinding means 3a that performs rough grinding on the plate-like workpiece held by the holding means 2, and a second grinding means 3b that performs finish grinding on the roughly ground plate-like workpiece; Is arranged. The first grinding means 3 a and the second grinding means 3 b are disposed above the movement path of the holding means 2.

  As shown in FIG. 2, the first grinding means 3 a includes a spindle 30 having a substantially vertical axis, a housing 31 that rotatably supports the spindle 30, and a spindle 30 that is connected to the upper end of the spindle 30 and rotates. Motor 32, a mount 33 fixed to the lower end of the spindle 30, and a wheel 34 fixed to the mount 33. A rough grinding wheel 35a is fixed to the lower surface of the wheel 34 in an annular shape.

  The second grinding means 3b is also configured in the same manner, and only the type of grinding wheel is different from the first grinding means 3a, and includes a finishing grinding wheel 35b instead of the rough grinding wheel 35a.

  As shown in FIG. 1, the 1st grinding means 3a and the 2nd grinding means 3b are provided with the raising / lowering mechanism 36 for raising / lowering the wheel 34. As shown in FIG. The elevating mechanism 36 includes a ball screw 360 having an axial center in the same direction as the spindle 30, a guide rail 361 disposed parallel to the ball screw 360, and a motor 362 connected to the ball screw 360 and rotating the ball screw 360. And an elevating member 363 which is provided with a nut screwed to the ball screw 360 and whose side portion is in sliding contact with the guide rail 361 and is connected to the housing 31, and is driven by the motor 362 to rotate the ball screw 360. As a result, the elevating member 363 is raised and lowered while being guided by the guide rail 361, and the housing 31 is also raised and lowered.

  As shown in FIG. 2, the holding means 2 includes a porous member 20 at the top, and the porous member 20 communicates with a suction source (not shown). The upper surface of the porous member 20 is a holding surface 20a that holds one surface of the plate-like workpiece, and the holding means 2 is centered on a rotating shaft 200 that is orthogonal to the holding surface 20a and passes through the center of the holding surface 20a. It can be rotated.

  As shown in FIG. 1, in the processing area B, a thickness measuring gauge 9a for measuring the thickness of the plate-like workpiece held by the holding means 2 positioned below the first grinding means 3a, and the second grinding means 3b A thickness measuring gauge 9b for measuring the thickness of the plate-like workpiece held by the holding means 2 positioned below is disposed.

  The individual thickness measurement gauges 9a and 9b include a reference height gauge 90 that measures the height position of the holding surface 20 of the holding means 2 that is a reference surface for thickness measurement, and a work height gauge that measures the height position of the surface of the plate-like workpiece. 91, and the difference between the measured value of the reference height gauge 90 and the measured value of the workpiece height gauge 91 is recognized as the thickness of the plate-like workpiece.

  As shown in FIG. 1, non-contact type thickness measuring means 10 for measuring the thickness of the plate-like workpiece held by the holding means 2 is disposed below the second grinding means 3b. The thickness measuring unit 10 includes a measuring unit 100 that measures the thickness of the plate-like workpiece in a non-contact state at a plurality of locations from above the plate-like workpiece held on the holding surface 20, and a holding unit based on the measurement value in the measuring unit 100. And a calculation unit 101 that calculates the inclination of the second rotation axis.

  The measuring unit 100 is supported by a stand 102 erected on the outer peripheral side of the turntable 2 a and an arm unit 103 that extends from the stand 102 toward the upper side of the holding unit 2, and the measuring unit 100 is supported by the arm unit 103. The three sensors 104a, 104b, and 104c are fixed to each other. The sensors 104a, 104b, and 104c irradiate the plate-shaped workpiece with measurement light, and receive the reflected light reflected by the upper and lower interfaces (upper surface and lower surface) of the plate-shaped workpiece. Thickness can be calculated.

  The calculation unit 101 is connected to a control unit 105 including at least a CPU and a memory, and the value of the inclination of the rotation axis of the holding unit 2 obtained by the calculation unit 101 is sent to the control unit 105. In the control unit 105, each part of the grinding apparatus 1 is controlled according to the value of the inclination of the rotation axis of the holding unit 2.

  As shown in FIG. 3, each holding unit 2 includes an inclination adjusting unit 21 that adjusts the inclination of the rotation shaft 200.

  The inclination adjusting means 21 includes a support base 22 and a position adjustment unit 23 connected to the support base 22. The support base 22 is composed of a cylindrical support cylinder part 220 and a flange part 221 whose diameter is larger than that of the support cylinder part 220. As shown in FIG. The part 200a is rotatably supported. The inclination adjusting means 21 has a function of adjusting the inclination of the shaft part 200a by adjusting the inclination of the flange part 221.

  Two or more position adjustment units 23 shown in FIG. 3 are provided at equal intervals along the arc of the flange portion 221. For example, as illustrated in FIG. 5, two position adjustment units 23 and a fixing portion 23 a that fixes the flange portion 221 are disposed at intervals of 120 degrees. Three or more position adjustment units 23 may be provided.

  As shown in FIG. 6, the position adjustment unit 23 includes a cylindrical portion 230 fixed to the turntable 2 a by screws 25, a shaft 231 that penetrates the cylindrical portion 230, and a drive portion 232 that is connected to the lower end of the shaft 231. The fixing portion 233 is fixed to the flange portion 221 at the upper end of the shaft 231. The drive unit 232 includes a motor 232a that rotates the shaft 231 and a speed reducer 232b that weakens the rotational speed of the shaft 231.

  Further, a belt 260 is wound around the shaft portion 200 a, and this belt 260 is also wound around the rotation shaft 261. The rotating shaft 261 is configured to be rotationally driven by a motor 262. When the rotating shaft 261 is rotated by being driven by the motor 262, the rotational force is transmitted to the shaft portion 200a by the belt 260. The holding means 2 is rotated by rotating the shaft portion 200a. A pipe 200b is formed through the shaft portion 200a, and the pipe 200b communicates with a suction source (not shown).

  As shown in FIG. 7, a first male screw 231 a is formed at the upper end of the shaft 231. On the other hand, the fixing portion 233 includes a nut 234 having a first female screw 234a screwed to the first male screw 231a, and a clamping nut 235 fixed to the nut 234 by a bolt 235a. The nut 234 and the clamping nut 235 And the flange portion 221 is sandwiched. A spring 235b is interposed between the bolt 235a and the shaft 231.

  The cylinder part 230 is supported in the hole 1c formed in the turntable 2a. Further, the lower end portion of the shaft 231 is connected to the speed reducer 232b and the motor 232a via the coupling 232c, and the shaft 231 can be rotated by driving by the motor 232a.

  As shown in FIG. 8, the holding surface 20 a of the holding means 2 is formed in a conical surface with the rotation center 200 as a vertex. That is, the holding surface 20a is formed as a slope having an inclination that descends from the rotation center toward the outer peripheral side. Corresponding to this inclination, the lower surfaces of the rough grinding wheel 35a constituting the first grinding means 3a and the finish grinding wheel 35b constituting the second grinding means 3b are also parallel to the holding surface 20a. Further, the workpiece W to be ground is also held along the conical surface. In FIG. 8, the inclination of the conical surface is exaggerated, but in actuality, the inclination is so slight that it cannot be recognized with the naked eye.

  Further, as shown in FIG. 9, above a part of the holding surface 20 a of the holding means 2 located below the second grinding means 3 b, parallel to the holding surface 20 a in the radial direction around the rotation axis 200. In addition, three sensors 104a, 104b, 104c are arranged in a straight line.

  In the grinding apparatus 1 configured as described above, the transport robot 5 shown in FIG. 1 takes out the plate-shaped workpiece before grinding from the supply cassette 4 a and transports it to the temporary placement means 6. Then, after the center position of the plate-like workpiece is adjusted to a fixed position in the temporary placement means 6, the first conveying means 8 a conveys the plate-like workpiece to the holding means 2 located in the detachable area A. The plate-like workpiece W is held on the holding surface 20a.

(1) Grinding step The holding means 2 holding the plate-like workpiece enters the machining area B by the rotation of the turntable 2a in the direction of arrow C and moves below the first grinding means 3a. Then, as shown in FIG. 8, while the holding means 2 rotates in the direction of arrow D, the first grinding means 3a is lowered while rotating the spindle 30 in the direction of arrow E, and the rotating rough grinding wheel 35a is replaced with a plate-like workpiece. Rough grinding is performed in contact with the upper surface W1 of W. The grinding is performed such that the rough grinding wheel 35a is always in contact with the rotation center of the upper surface W1 of the workpiece W.

  After the completion of the rough grinding, the turntable 2a is further rotated in the same direction to move the roughly ground plate-like workpiece W below the second grinding means 3b. As shown in FIG. 9, the holding means 2 rotates in the direction of arrow D, and the second grinding means 3b is lowered while rotating the spindle 30 in the direction of arrow E. Finish grinding is performed by contacting the upper surface W1 of W. As shown in FIG. 10, the finish grinding is performed such that the finish grinding wheel 35b is always in contact with the center of rotation of the upper surface W1 of the plate-like workpiece W.

  In the second grinding means 3b, before the plate-like workpiece W is formed to a desired finish thickness, the wheel 34 is raised to temporarily stop grinding, and the thickness measuring means 10 measures the thickness of the plate-like workpiece W. . Specifically, the three sensors 104a, 104b, and 104c are used to determine the rotation center of the plate-like workpiece W, the outer peripheral end of the plate-like workpiece W, and the intermediate point between the rotation center and the outer peripheral end of the plate-like workpiece W. At each location, the thickness of the plate-like workpiece W is measured. By measuring the thickness at each of the three places, the calculation unit 101 shown in FIGS. 1 and 2 recognizes the variation in the thickness of the plate-like workpiece W.

(2) Inclination Adjustment Step Next, the inclination of the rotating shaft 200 of the holding means 2 is adjusted by the inclination adjusting means 21. First, in the calculation unit 101, for example, based on the measured values of the thickness of the three positions of the plate-like workpiece W by the three sensors 104a, 104b, and 104c, for example, the difference between the measured value of 104a and the measured value of 104c, The inclination of the rotating shaft 200 can be obtained from the difference between the measured value and the average value of the measured value of 104c and the measured value of 104b. And when the calculated | required inclination of the rotating shaft 200 is not a predetermined value, it adjusts so that the inclination of the rotating shaft 200 may become a predetermined value. In addition, if the inclination 20b of the holding surface 20a in FIG. 9 is parallel to the inclination 35d of the lower surface 35c of the finish grinding wheel 35b, it can be determined that the inclination of the rotating shaft 200 is the predetermined value.

  When grinding is performed in a state where the inclination of the rotary shaft 200 does not reach a predetermined value, for example, like the plate-like workpieces Wa to Wd shown in FIGS. . The plate-like workpiece Wa shown in FIG. 11 has a measured value of 104a−measured value of −104c> 0 (zero) because the inclination of the rotating shaft 200 is too large, and the central portion of the plate-like workpiece W is formed thick, and the outer peripheral side is Thinly formed. The plate-like workpiece Wb shown in FIG. 12 has a measured value of 104a−measured value of −104c <0 (zero) because the inclination of the rotary shaft 200 is too small, and the central portion of the plate-like workpiece W is formed thin, and the outer peripheral side is It is formed thick. 13 is (measured value of 104a + measured value of 104c) / 2−measured value of 2-104b <0 (zero), and the plate-like workpiece Wd shown in FIG. 14 is (measured value of 104a + 104c). Measurement value) / 2-104b measurement value> 0 (zero) and the inclination of the rotary shaft 200 is inappropriate, so that the upper surface (surface to be ground) of the plate-like workpiece W is not formed flat.

  Adjustment of the inclination of the rotating shaft 200 is performed using the two position adjusting units 23 shown in FIG. Specifically, the difference between the actual value of the inclination of the rotating shaft 200 and a predetermined value is calculated by the calculation unit 101, and the rotation driving of the holding means 2 by the motor 262 is stopped, as shown in FIG. The controller 105 drives the motor 232a and rotates the shaft 231 to move the flange 221 up and down. When the motor 232a is driven, the rotation driving of the holding unit 2 by the motor 262 may be stopped.

  As the flange portion 221 moves up and down, the inclination of the shaft portion 200a of the holding means 2 supported by the support base 22 including the flange portion 221 changes as shown in FIG. The tilt can be adjusted. In this way, fine adjustment of the rotating shaft 200 is completed.

(3) Re-grinding step After the tilt adjustment of the rotating shaft 200 of the holding means 2 is thus adjusted by the tilt adjusting means 21, the holding means 2 rotates in the direction of arrow D as shown in FIG. Then, the second grinding means 3b is lowered while rotating the spindle 30 in the direction of arrow E, the rotating grinding wheel 35b is brought into contact with the upper surface W1 of the plate-like workpiece W, and finishing grinding is performed again. Then, when it is confirmed by the thickness measurement gauge 9b shown in FIG. 1 that the plate-like workpiece W has been formed to the specified thickness, the finish grinding is finished.

  In the regrinding step, the finish grinding is performed in a state in which the rotation shaft 200 of the holding means 2 is corrected to a predetermined inclination. Therefore, even if the thickness of the plate-like workpiece W varies in the grinding step, the regrind is performed. Thickness variation is eliminated by grinding in the step, and a plate-like workpiece having a uniform thickness can be formed.

  After finishing grinding, the plate-like workpiece W is transferred to the cleaning means 7 by the second transfer means 8b and cleaned, and then stored in the recovery cassette 4b by the transfer robot 5.

(4) Modification Example of Thickness Measuring Means Note that the thickness measuring means 11 shown in FIG. 15 can be used instead of the thickness measuring means 10 shown in FIG. The thickness measuring unit 11 includes a measuring unit 110 including a sensor that measures the thickness of the plate-like workpiece in a non-contact state from above the plate-like workpiece held on the holding surface 20, and the holding unit based on the measurement value in the measuring unit 110. And a calculation unit 111 that calculates the inclination of the second rotation axis.

  The measuring unit 110 is fixed to an arm unit 113 that is provided on the outer peripheral side of the turntable 2 a and extends from the rotatable stand 112 toward the upper side of the holding unit 2, and can be turned by the rotation of the stand 112. . A belt 114 is wound around the stand 112, and the belt 114 is wound around a rotating shaft 115 a of the motor 115. When the rotating shaft 115 a is driven to rotate by the motor 115, the rotational force is applied by the belt 114. The arm 113 is transmitted to the stand 112 and pivoted.

  When measuring the thickness of the workpiece W held by the holding means 2, the grinding is temporarily interrupted, the arm portion 113 is turned, and the measuring portion 110 is moved in the direction of the holding surface 20 a and held by the holding means 2. The measuring unit 110 is scanned from the rotation center of the plate-shaped workpiece W to the outer peripheral end W2 or from the outer peripheral end W2 toward the rotation center.

  By scanning the measurement unit 110, it is possible to measure three thicknesses of the rotation center, the outer peripheral edge, the outer peripheral edge, and the midpoint (1 / 2R) of the rotation center of the plate-like workpiece W. Then, the inclination of the rotating shaft 200 of the holding means 2 is obtained from the measured thickness value, and is corrected to a desired inclination by the inclination adjusting means 21. After that, grinding is resumed, and when the plate-like workpiece W is formed with a predetermined thickness by measurement by the thickness measurement gauge 9b, the grinding is finished.

  Although the grinding apparatus 1 shown in FIG. 1 includes two grinding means, only one grinding means or three or more grinding apparatuses may be used.

1: Grinding apparatus A: Removable area B: Processing area 2: Holding means 20: Porous member 20a: Holding surface 200: Rotating shaft 200a: Shaft portion 21: Inclination adjusting means 22: Support base 220: Support cylinder portion 221: Flange portion 23: Position adjustment unit 230: Tube portion 231: Shaft 231a: First male screw 232: Drive portion 232a: Motor 232b: Reducer 232c: Coupling 233: Fixing portion 234: Nut 234a: First female screw 235: Holding nut 235a: Bolt 24: Bearing 25: Screw 260: Belt 261: Rotating shaft 262: Motor 2a: Turntable 3a: First grinding means 3b: Second grinding means 30: Spindle 31: Housing 32: Motor 33: Mount 34: Wheel 35a: Coarse grinding wheel 35b: Finish grinding wheel 36: Lifting mechanism 3 0: Ball screw 361: Guide rail 362: Motor 363: Elevating member 4a: Supply cassette 4b: Collection cassette 5: Transfer robot 6: Temporary placing means 7: Cleaning means 8a: First transfer means 8b: Second transfer means 9a, 9b: Thickness measuring gauge 90: Reference height gauge 91: Work height gauge 10: Thickness measuring means 100: Measuring part 101: Calculation part 102: Stand 103: Arm parts 104a, 104b, 104c: Sensor 105: Control part 11: Thickness measuring means 110 : Measurement unit 111: Calculation unit 112: Stand 113: Arm unit 114: Belt 115: Motor 115 a: Rotating shaft

Claims (2)

A holding means capable of holding and rotating a plate-like work, a grinding means provided with an elevating mechanism for grinding the plate-like work held by the holding means, and a thickness of the plate-like work held by the holding means are measured. A grinding device comprising at least a thickness measuring means,
The holding means includes at least a holding surface that holds one surface of the plate-like workpiece, a rotation axis that passes through the center of the holding surface, and an inclination adjustment means that adjusts the inclination of the rotation axis,
The thickness measuring means includes an outer peripheral end of the plate-shaped workpiece from above the plate-shaped workpiece held on the holding surface, a rotation center of the plate-shaped workpiece, and an intermediate between the rotation center and the outer peripheral end of the plate-shaped workpiece. a measuring unit for measuring a point, the thickness of the plate-shaped workpiece in three places in a non-contact state, a calculation unit for calculating an inclination of the rotary shaft based on the measured values at the measurement portion, is calculated in the calculated output unit A controller that receives the value of the tilt of the rotation axis and drives the tilt adjusting means based on the tilt value ;
The grinding means temporarily stops grinding before the plate-like workpiece reaches the finished thickness, measures the thickness of the plate-like workpiece by the thickness measuring means, and calculates the value of the inclination of the rotation axis calculated by the calculation unit. The control unit corrects the inclination of the rotating shaft by driving the inclination adjusting means based on the difference between the predetermined inclination value and the predetermined inclination value until the grinding means again forms a predetermined finished thickness. A grinding device for grinding the plate-like workpiece.   The grinding apparatus according to claim 1, wherein the thickness of the plate-like workpiece is measured by scanning the measurement unit from the rotation center of the plate-like workpiece held by the holding means toward the outer peripheral end.

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