Grinding method and grinding device for adhering a workpiece

Abstract

The present application provides a grinding method and a grinding device for a workpiece. The grinding method for the workpiece includes, before a process of holding the workpiece by a holding surface of a support member facing the workpiece, a process of taking a picture of the workpiece by a camera in a manner that an outer periphery of the support member is included in the picture and the outer periphery of the workpiece is included in the picture; a process of identifying the outer periphery of the support member and the outer periphery of the workpiece by a difference in brightness of pixels adjacent to each other in the picture; and a process of identifying a center of the support member based on the identified outer periphery of the support member and identifying a center of the workpiece based on the identified outer periphery of the workpiece. In the holding process, the workpiece is ground after selectively implementing a case where the workpiece is held with the center of the holding surface coinciding with the center of the support member and a case where the workpiece is held with the center of the holding surface coinciding with the center of the workpiece.

Description

TECHNICAL FIELD

[0001] The present application relates to a polishing method of a bonded workpiece in which two transparent members or translucent members are bonded, and a polishing apparatus of the bonded workpiece. BACKGROUND

[0002] In a polishing apparatus in which a workpiece such as a semiconductor wafer is polished by a polishing tool, as disclosed in Patent Document 1, for example, before the workpiece on which a tape is attached on one surface is carried into a chuck table, the outer periphery of the workpiece is detected, the center of the workpiece is recognized based on the detected outer periphery, the center of the holding surface is made to coincide with the center of the workpiece, and the workpiece is held on the holding surface to be polished by the polishing tool.

[0003] When lithium tantalate (LiTaO3) as a workpiece is polished by a polishing tool, when a tape is attached on one surface of the lithium tantalate and polishing is performed in a state in which the one surface side is held, there is a problem that the thinned lithium tantalate is bent and broken. Therefore, in order to prevent the thinned lithium tantalate from being bent, instead of the tape, lithium tantalate is attached on a substrate (support member) of a harder material such as transparent or translucent glass, the substrate side is held, and the lithium tantalate is polished.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2009-123790

[0005] With respect to a bonded workpiece in which a support member and lithium tantalate are bonded, the center of the support member is slightly shifted from the center of the lithium tantalate. Therefore, in order to ensure that the lithium tantalate does not protrude from the support member even if the centers are slightly shifted from each other and the lithium tantalate is bonded, the diameter of the lithium tantalate is smaller than that of the support member.

[0006] In addition, in order to reduce the thickness difference of the thinned lithium tantalate by polishing, a notch or an orientation flat indicating crystal orientation is not formed on the outer periphery of the lithium tantalate, a mark indicating crystal orientation is formed on the support member, the center of the lithium tantalate is made to coincide with the center of the holding surface, the bonded workpiece is held on the holding surface, and the lithium tantalate is polished by the polishing tool to be thinned. That is, there is a case in which the center of the holding surface does not coincide with the center of the support member at the time of polishing. In addition, in order to prevent vacuum leakage and to be able to cover the holding surface with the support member, the support member is larger than the holding surface.

[0007] The support member can be slightly larger than the holding surface in the case in which the mark indicating crystal orientation is formed on the lithium tantalate, and in polishing, the center of the support member can be made to coincide with the center of the holding surface to hold the bonded workpiece on the holding surface. SUMMARY

[0008] Therefore, an object of the present application is to provide a grinding method and a grinding apparatus capable of selectively switching between a case where the center of a support member is aligned with the center of a holding surface and a case where the center of a lithium tantalate as a workpiece is aligned with the center of the holding surface, while the bonded workpiece obtained by bonding two transparent members or translucent members is held on the holding surface of a chuck table.

[0009] According to one aspect of the present application, there is provided a grinding method of a bonded workpiece, which grinds a workpiece of a bonded workpiece obtained by bonding at least two transparent members or translucent members, the workpiece being in a circular plate shape and transparent or translucent, and a support member being in a circular plate shape and transparent or translucent, the size of which is larger than that of the workpiece and which projects outward from the outer periphery of the workpiece, using a grinding tool, wherein the grinding method of the bonded workpiece has: a photographing step of photographing the bonded workpiece so as to include the outer periphery of the workpiece and the outer periphery of the support member, using a camera; an outer periphery recognizing step of recognizing the outer periphery of the support member and the outer periphery of the workpiece, respectively, based on the difference in brightness of pixels adjacent to each other in a photographed image photographed by the photographing step; a center recognizing step of recognizing the center of the support member based on the outer periphery of the support member recognized by the outer periphery recognizing step, and recognizing the center of the workpiece based on the outer periphery of the workpiece recognized by the outer periphery recognizing step; a holding step of holding the support member of the bonded workpiece on a holding surface of a chuck table, after the center recognizing step is performed; and a grinding step of grinding the workpiece of the bonded workpiece held by the holding step using a grinding tool, the workpiece being ground by the grinding step after selectively performing either of a case where the center of the holding surface is aligned with the center of the support member to hold the support member and a case where the center of the holding surface is aligned with the center of the workpiece to hold the workpiece.

[0010] Preferably, the photographing step includes a temporary holding step of making the outer periphery of the workpiece and the outer periphery of the support member project from a temporary holding table to temporarily hold the bonded workpiece on the temporary holding table, in the photographing step, light is radiated upward from the lower side of the bonded workpiece temporarily held on the temporary holding table using an illumination section arranged on the lower side of the bonded workpiece, and the bonded workpiece is photographed so as to include the outer periphery of the workpiece and the outer periphery of the support member using the camera arranged opposite to the illumination section.

[0011] Preferably, in the photographing step, the bonded workpiece is photographed so as to include the outer periphery of the workpiece and the outer periphery of the support member of the bonded workpiece held by a conveyance unit which conveys the bonded workpiece to the holding surface, using the camera.

[0012] According to another aspect of the present application, there is provided a grinding device, wherein the grinding device has: a chuck table that holds a laminated workpiece obtained by laminating at least two transparent or translucent members, a workpiece that is in a circular plate shape and is transparent or translucent, and a support member that is in a circular plate shape and is transparent or translucent, the size of which is larger than that of the workpiece and which protrudes outward from the outer periphery of the workpiece; a grinding unit that grinds the workpiece held by the holding surface of the chuck table using a grindstone; a conveyance unit that conveys and holds the laminated workpiece onto the holding surface of the chuck table; a camera that photographs the laminated workpiece; and a control unit that controls at least the chuck table, the grinding unit, the conveyance unit, and the camera, the control unit including: an outer periphery recognition section that recognizes the outer periphery of the support member and the outer periphery of the workpiece based on a photographed image of the laminated workpiece including the outer periphery of the workpiece and the outer periphery of the support member before the laminated workpiece is held by the holding surface of the chuck table; a center recognition section that recognizes the center of the support member based on the outer periphery of the support member recognized by the outer periphery recognition section, and recognizes the center of the workpiece based on the outer periphery of the workpiece recognized by the outer periphery recognition section; and a setting section that sets whether the center of the holding surface is made to coincide with the center of the support member or the center of the holding surface is made to coincide with the center of the workpiece when the laminated workpiece is held on the holding surface of the chuck table, the control unit controlling the conveyance unit so that the laminated workpiece is held on the holding surface of the chuck table in accordance with the setting of the setting section.

[0013] Preferably, the support member has a mark indicating the crystal orientation of the workpiece, the holding surface of the holding unit is the same shape as the support member when viewed from above, the holding unit includes a holding surface rotation unit that rotates the holding surface about the center of the holding surface, and the control unit controls the holding surface rotation unit so that the mark of the support member of the laminated workpiece held by the conveyance unit coincides with a corresponding mark formed on the holding surface corresponding to the mark.

[0014] According to the grinding method of the present application, in the holding step, either the case where the center of the holding surface is made to coincide with the center of the support member or the case where the center of the holding surface is made to coincide with the center of the workpiece can be selectively implemented, and then the workpiece can be ground by the grinding step.

[0015] The photographing process includes a temporary placement process of projecting the outer periphery of the workpiece and the outer periphery of the support member from a temporary placement table to temporarily place the bonded workpiece on the temporary placement table, and in the photographing process, light is irradiated from the lower side to the upper side of the bonded workpiece using an illuminating section disposed below the bonded workpiece temporarily placed on the temporary placement table, and the bonded workpiece is photographed by a camera disposed opposite the illuminating section in a manner including the outer periphery of the workpiece and the outer periphery of the support member, whereby a photographing image required in an outer periphery recognition process performed after the photographing process can be easily obtained.

[0016] In the photographing process, the bonded workpiece is photographed by the camera in a manner including the outer periphery of the workpiece and the outer periphery of the support member of the bonded workpiece held by the conveying unit conveyed onto the holding surface, whereby a photographing image required in an outer periphery recognition process performed after the photographing process can be easily obtained.

[0017] According to the grinding device of the present application, the case where the center of the holding surface is aligned with the center of the support member and the case where the center of the holding surface is aligned with the center of the workpiece are selectively implemented, and thereafter, the workpiece can be ground.

[0018] The support member has a mark indicating the crystal orientation of the workpiece, the holding surface of the holding unit has the same shape as the support member in plan view, and the holding unit has a holding surface rotation unit that rotates the holding surface with the center of the holding surface as an axis, whereby the control unit controls the holding surface rotation unit to align the mark of the support member of the bonded workpiece held by the conveying unit with a corresponding mark corresponding to the mark formed on the holding surface, and thereafter, the workpiece can be thinned to a uniform thickness by grinding. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a perspective view showing an example of a grinding device.

[0020] Figure 2 is a side view showing a case where the bonded workpiece is photographed by the camera in a manner including the outer periphery of the workpiece and the outer periphery of the support member in the photographing process of the first embodiment.

[0021] Figure 3 is a schematic view showing an example of a photographing image photographed by the photographing process.

[0022] Figure 4 is a side view showing a case where the bonded workpiece is photographed by the camera in a manner including the outer periphery of the workpiece and the outer periphery of the support member in the photographing process of the second embodiment.

[0023] Figure 5 is an example of a graph in which the group value is shown as the vertical axis and the position in the X-axis direction of the captured image is shown as the horizontal axis.

[0024] BRIEF DESCRIPTION OF DRAWINGS

[0025] 8: bonded workpiece; 80: workpiece; 801: front surface of workpiece; 802: ground surface of workpiece; 807: outer periphery of workpiece; 82: support member; 820: front surface of support member; 822: back surface of support member; 828: outer periphery of support member; 825: mark of support member; 1: grinding device; 10: device base; 100: carry-in and carry-out area; 101: processing area; 18: column; 150: 1st cassette stage; 151: 2nd cassette stage; 21: 1st cassette; 22: 2nd cassette; 11: temporary holding stage; 118: temporary holding stage rotation unit; 1181: motor; 1182: main shaft; 116: temporary holding stage support base; 14: photographing unit; 141: illumination section; 142: camera; 5: conveyance unit; 50: robot; 500: robot hand; 5004: suction surface; 502: hand horizontal movement mechanism; 504: hand up and down movement mechanism; 506: hand inversion mechanism; 507: arm connection section; 52: loading arm; 520: conveyance pad; 521: arm section; 522: rotation shaft section; 132: unloading arm; 12: cleaning unit; 120: rotary stage; 121: cleaning nozzle; 3: holding unit; 30: chuck stage; 302: holding surface; 304: corresponding mark; 39: cover; 36: holding surface rotation unit; 360: motor; 362: main shaft; 38: thickness measurement unit; 19: grinding feed mechanism; 16: grinding unit; 164: grinding wheel; 1640: grinding tool; 9: control unit; 90: outer periphery recognition section; 92: center recognition section; 94: setting section. DETAILED DESCRIPTION

[0026] Figure 1 The grinding device 1 shown is a device that grinds the workpiece 80 of the bonded workpiece 8 held by the chuck stage 30 of the holding unit 3 using the grinding unit 16. The front side (-Y direction side) of the device base 10 of the grinding device 1 becomes the carry-in and carry-out area 100 in which the bonded workpiece 8 is carried in and carried out with respect to the chuck stage 30, and the rear side (+Y direction side) of the device base 10 becomes the processing area 101 in which the bonded workpiece 8 held on the chuck stage 30 is ground by the grinding unit 16.

[0027] In addition, the processing apparatus of the present application can be configured to have two axes of a rough grinding unit and a finish grinding unit as the grinding units, and the chuck table 30 holding the adhered workpiece 8 by the rotating table is positioned below each grinding unit.

[0028] The workpiece ground by the grinding apparatus 1 is Figure 1 The adhered workpiece 8 shown is obtained by adhering at least two transparent or translucent members of the workpiece 80 in a circular plate shape and transparent or translucent and the support member 82 in a circular plate shape and transparent or translucent and the size of the workpiece 80 outwardly protruding from the outer periphery 807.

[0029] The workpiece 80 is, for example, a circular wafer composed of lithium tantalate as a transparent or translucent member, and in Figure 1 The front surface 801 of the workpiece 80 facing downward is adhered to the front surface 820 of the support member 82 using an adhesive or the like not shown in the present embodiment. The back surface of the workpiece 80 opposite to the front surface 801 becomes the ground surface 802 on which grinding processing is performed. In addition, the workpiece 80 can be a wafer formed of SiC as a transparent or translucent member.

[0030] The support member 82 having a larger diameter than the workpiece 80 is composed of transparent or translucent glass, and in Figure 1 The back surface 822 facing downward becomes a held surface held by the holding surface 302 of the chuck table 30. In addition, the support member 82 can be formed of sapphire or spinel or the like as a transparent or translucent member in addition to glass. In addition, the glass constituting the support member 82 can be colored transparently or translucently.

[0031] The adhered workpiece 8 is processed as a whole by the workpiece 80 and the support member 82, and the operability of the thin workpiece 80 after grinding can be improved, and warping and breakage of the workpiece 80 can be prevented. Sometimes the center of the workpiece 80 of the adhered workpiece 8 is slightly offset from the center of the support member 82.

[0032] In the present embodiment, a mark 825 indicating the crystal orientation of the workpiece 80 is formed on the outer periphery 828 of the support member 82. The mark 825 is formed, for example, by cutting the outer peripheral portion of the support member 82 flatly in the tangential direction.

[0033] Alternatively, an orientation plane indicating the crystal orientation can be formed on the workpiece 80 by straightly cutting off a portion of its outer periphery. Alternatively, a notch indicating the crystal orientation of the workpiece 80 can be formed on the outer periphery of the workpiece 80 in a radially inward recessed state, facing the center of the workpiece 80. In these cases, the support member 82 may also be a circle without the marking 825 indicating the crystal orientation of the workpiece 80 formed thereon.

[0034] On the front side (-Y direction side) of the base 10 of the grinding apparatus 1, there are a first box platform 150 and a second box platform 151 for holding multiple boxes that can be arranged in a shelf-like manner to hold multiple workpieces 8. The first box platform 150 holds a first box 21 that holds multiple workpieces 8 before processing in a shelf-like manner, and the second box platform 151 holds a second box 22 that holds multiple workpieces 8 after processing in a shelf-like manner.

[0035] The grinding apparatus 1 has a conveying unit 5 that conveys and holds the workpiece 8 on the holding surface 302 of the holding unit 3. In this embodiment, the conveying unit 5 has: a robot 50 that removes the workpiece 8 from the first box 21; and a loading arm 52 that moves the workpiece 8, for example, placed on the temporary worktable 11 by the robot 50 and having its center or the center of the support member 82 identified, from the temporary worktable 11 to the chuck worktable 30.

[0036] like Figure 1 As shown, a robot 50 is disposed behind the opening on the +Y direction side of the first box 21. The robot 50 is a joint robot, which has: a robot hand 500 having an adsorption surface for adsorbing and holding the workpiece 8; a hand horizontal movement mechanism 502 for moving the robot hand 500 in the horizontal direction; a hand vertical movement mechanism 504 such as an electric actuator for moving the robot hand 500 in the vertical direction; and a hand reversal mechanism 506 for reversing, for example, the adsorption surface 5004 of the robot hand 500 vertically.

[0037] The hand horizontal movement mechanism 502 is composed of multiple arm components, and is configured to rotate a rotating arm with an internal pulley mechanism via a rotary motor. The hand horizontal movement mechanism 502 enables the robot hand 500 to rotate and move in the horizontal plane (in the X-axis and Y-axis planes), and can deform the multiple arm components from an intersecting state to a state in which they are aligned with each other, and can enable the robot hand 500 to move linearly in the horizontal plane.

[0038] A hand up-and-down movement mechanism 504 is connected to the lower side of the hand horizontal movement mechanism 502, and the hand up-and-down movement mechanism 504 moves the robot hand 500 up and down in the Z-axis direction together with the hand horizontal movement mechanism 502, thereby positioning the robot hand 500 at a prescribed height.

[0039] A housing 5063 that will be described later is fixed to the arm member of the hand horizontal movement mechanism 502 via a columnar arm joint 507. Figure 1 A spindle 5062 having an axis perpendicular to the Z-axis direction, i.e., the Y-axis direction, is rotatably supported in the housing 5063. For example, a reversing motor that rotates the spindle 5062 is housed in the interior of the housing 5063.

[0040] The front end side of the spindle 5062 protrudes in the -Y direction from the housing 5063, and a holder that mounts the root side of the robot hand 500 is provided at the front end side. The reversing motor, not shown, rotates the spindle 5062 by a prescribed angle, and in conjunction therewith, the robot hand 500 connected to the spindle 5062 via the holder is rotated, and the suction surface 5004 of the robot hand 500 can be reversed and switched.

[0041] The plate-shaped robot hand 500 that holds and suctions the fitted workpiece 8 has, for example, a substantially U-shaped appearance in plan view as a whole. In addition, the robot hand 500 is not limited to the shape of the present embodiment, and can have a substantially spoon shape in plan view as a whole.

[0042] For example, the surface in the Figure 1 upward direction of the robot hand 500 is the suction surface 5004 that suctions and holds the fitted workpiece 8. In addition, the opposite surface of the suction surface 5004 of the robot hand 500 can also be the suction surface. The suction surface 5004 is smoothly finished, and in addition, the end portion of the suction surface 5004 can also be chamfered so as not to damage the fitted workpiece 8. A plurality of suction holes are provided in the suction surface 5004. In addition, a deformable rubber suction pad or the like can be provided in the suction holes. Furthermore, in order not to interfere with the rotational movement of the robot hand 500, a flexible resin tube is connected to each of the suction holes via a joint or the like, and the resin tube is connected to a suction source such as a vacuum generating device or an ejector mechanism.

[0043] A temporary placement table 11 is provided at a position adjacent to the robot 500. The circular temporary placement table 11 has, for example, a smaller diameter than the fitted workpiece 8, and the flat upper surface of the temporary placement table 11 is a temporary placement surface that temporarily places the fitted workpiece 8. The temporary placement surface is connected to a suction source, not shown, and can suction and hold the fitted workpiece 8.

[0044] A temporary placement stage 11 is connected on the lower side thereof to a temporary placement stage rotation unit 118 composed of a motor 1181 and a main shaft 1182, and the like, and the temporary placement stage 11 is able to rotate by the main shaft 1182 in the Z-axis direction. The main shaft 1182 is supported so as to be able to rotate by a temporary placement stage support base 116 provided on the device base 10 via a bearing, or the like, not shown.

[0045] The motor 1181 is, for example, a servo motor, and an encoder 1189 of the motor 1181 is connected to a control unit 9 shown in the drawing, and also has a function as a servo amplifier. Figure 1 The control unit 9 shown in the drawing is connected, and after an operation signal is supplied from an output interface of the control unit 9 to the motor 1181 and the main shaft 1182 rotates, a detected rotation angle is outputted to an input interface of the control unit 9 as an encoder signal. Also, the control unit 9 which receives the rotation angle of the motor 1181 as an encoder signal is able to recognize the rotation angle of the temporary placement stage 11.

[0046] In the present embodiment, a photographing unit 14 for photographing the adhered workpiece 8 is provided in the vicinity of the temporary placement stage 11. Also, the photographing unit 14 has, for example, an illumination section 141 which is, for example, coaxial downlight, is provided on the temporary placement stage support base 116, and is positioned at a position lower than the temporary placement stage 11, and a camera 142 which opposes the illumination section 141 in the Z-axis direction.

[0047] The illumination section 141 is composed of, for example, an LED (Light Emitting Diode) which is able to emit a plurality of visible lights, but is not limited thereto, and can be a xenon lamp, or the like. When power is supplied from a not shown power source connected thereto, the illumination section 141 emits light, and irradiates light upward toward the camera 142.

[0048] The camera 142 is, for example, mounted on the front end of the upper portion of a support column 146 which is a substantially L-shaped support column vertically provided on the temporary placement stage support base 116, and is composed of an optical system such as a lens which captures light emitted from the illumination section 141, and a light receiving element such as a CCD which outputs an object image imaged by the optical system. Also, the camera 142 can be able to move in the horizontal direction.

[0049] A loading arm 52 is provided in the vicinity of the temporary placement table 11. The loading arm 52 has an arm portion 521 extending in parallel with the horizontal direction, a rotation shaft portion 522 whose axial direction is the Z-axis direction and which moves the arm portion 521 in the horizontal direction in rotation, and a transport pad 520 which attracts and holds the fitted workpiece 8 with its lower surface. The loading arm 52 is capable of moving up and down, for example, by a cylinder mechanism not shown. The loading arm 52 attracts and holds the fitted workpiece 8 temporarily placed on the temporary placement table 11, for example, and transports it to the chuck table 30 of the holding unit 3 positioned in the vicinity of the loading arm 52.

[0050] In Figure 1 In the example shown, the diameter of the transport pad 520 is smaller than the diameter of the workpiece 80, and only the central region of the ground surface 802 of the workpiece 80 is attracted and held, but it can also be configured to attract and hold substantially the entire surface of the ground surface 802 of the workpiece 80. The transport pad 520 is capable of attracting and holding the fitted workpiece 8 with a flat lower surface composed of a porous member or the like.

[0051] A unloading arm 132 composed of an attraction pad or the like is provided next to the loading arm 52 and rotates in a state of attracting and holding the ground surface 802 of the machined workpiece 80.

[0052] A single-piece cleaning unit 12 which cleans the machined fitted workpiece 8 transported by the unloading arm 132 is disposed within the movable range of the unloading arm 132. The cleaning unit 12 attracts and holds the support member 82 with a rotary table 120 having a smaller diameter than the fitted workpiece 8, and a cleaning nozzle 121 which moves in rotation above the held workpiece 80 sprays cleaning water to the upper surface, i.e., the ground surface 802 of the rotating workpiece 80, thereby cleaning the ground surface 802. In addition, the cleaning nozzle 121 can spray air to dry the cleaned fitted workpiece 8.

[0053] The holding unit 3 has a chuck table 30 which is capable of attracting and holding the support member 82 of the fitted workpiece 8 with a holding surface 302. In the present embodiment, the chuck table 30 has an adsorption portion 300 composed of a porous member or the like which adsorbs the support member 82, and a frame 301 which supports the adsorption portion 300. The adsorption portion 300 communicates with an attraction source not shown such as a vacuum generating device, and the attraction force generated by attraction of the attraction source is transmitted to the holding surface 302 which is the exposed surface (upper surface) of the adsorption portion 300, whereby the chuck table 30 is capable of attracting and holding the fitted workpiece 8 on the holding surface 302.

[0054] For example, the holding surface 302 corresponds to the mark 825 formed on the support member 82 as a flat cutout indicating the crystal orientation of the workpiece 80 and has the same shape as the support member 82 when viewed from above. That is, the outer periphery of the circular adsorption portion 300 is flatly cut in the tangential direction to form the corresponding mark 304. In addition, the center of the holding surface 302 of the chuck table 30 of the holding unit 3 is, for example, the center of the circle when the holding surface 302 is assumed to be a perfect circle.

[0055] The chuck table 30 is surrounded by the cover 39 of the holding unit 3 from the periphery and is capable of reciprocating in the Y-axis direction on the device base 10 by a not-shown table moving mechanism provided below the cover 39 and the bellows cover 390 connected to the cover 39. The not-shown table moving mechanism is a ball screw mechanism or the like that linearly moves a motor-driven slide in the Y-axis direction.

[0056] The holding unit 3 has a holding surface rotating unit 36 that rotates the chuck table 30 with the center of the holding surface 302 as an axis. The holding surface rotating unit 36 is configured to connect a main shaft 362 to the lower side of the chuck table 30 and to rotationally drive the main shaft 362 by a motor 360.

[0057] The motor 360 is, for example, a servo motor, and a rotation encoder 369 of the motor 360 is connected to the control unit 9 that also has the function of a servo amplifier. After the main shaft 362 is rotated by supplying an operation signal from the output interface of the control unit 9 to the motor 360, the rotation angle of the main shaft 362 is output to the input interface of the control unit 9 as an encoder signal. Furthermore, the control unit 9 that receives the encoder signal can recognize the rotation angle of the chuck table 30 and the circumferential position of the corresponding mark 304 of the flat cutout corresponding to the mark 825 of the support member 82 on the holding surface 302 of the chuck table 30.

[0058] A column 18 is erected at the rear (+Y direction side) of the processing area 101, and a grinding feed mechanism 19 is provided on the front surface of the -Y direction side of the column 18. The grinding feed mechanism 19 relatively feeds the grinding unit 16 and the chuck table 30 in the Z-axis direction perpendicular to the holding surface 302. The grinding feed mechanism 19 includes a ball screw 190 having an axis in the Z-axis direction, a pair of guide rails 191 provided parallel to the ball screw 190, a motor 192 coupled to the upper end of the ball screw 190 to rotate the ball screw 190, a lifting plate 193 having a nut screwed to the ball screw 190 and a side portion in sliding contact with the guide rails 191, and a holder 194 coupled to the lifting plate 193 to hold the grinding unit 16. When the motor 192 rotates the ball screw 190, the lifting plate 193 is guided by the guide rails 191 to reciprocate in the Z-axis direction, and the grinding unit 16 held by the holder 194 is fed in the Z-axis direction.

[0059] The grinding unit 16 grinds the workpiece 80 held by the holding surface 302 of the holding unit 3 using the grinding tools 1640. The grinding unit 16 includes a rotary shaft 160 having an axis in the Z-axis direction, a housing 161 rotatably supporting the rotary shaft 160, a motor 162 rotating the rotary shaft 160, a ring-shaped mounting seat 163 coupled to the lower end of the rotary shaft 160, and a grinding wheel 164 detachably mounted to the lower surface of the mounting seat 163.

[0060] The grinding wheel 164 includes a wheel base 1641 and a plurality of grinding tools 1640 in the shape of a substantially rectangular parallelepiped arranged in a ring on the bottom surface of the wheel base 1641. The grinding tools 1640 are formed by fixing abrasive grains or the like with a specified adhesive or the like, for example.

[0061] A flow path (not shown) serving as a passage for grinding water is formed through the rotary shaft 160 in the axial direction (Z-axis direction) of the rotary shaft 160. The flow path passes through the mounting seat 163 and opens on the bottom surface of the wheel base 1641 to be able to eject grinding water toward the grinding tools 1640.

[0062] A thickness measurement unit 38 that measures the thickness of the workpiece 80 in contact with the workpiece 80 during grinding is provided at a position near the grinding wheel 164 at a height position at which the grinding wheel 164 is lowered to grind the workpiece 80, for example. Alternatively, the thickness measurement unit 38 can be a non-contact thickness measurement unit.

[0063] The grinding device 1 has an outer periphery recognition section 90 that recognizes the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 by discriminating based on a captured image of the workpiece 8 including the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 captured by the capturing section 14 before the workpiece 8 is held by the holding surface 302 of the holding section 3, a center recognition section 92 that recognizes the center of the support member 82 based on the outer periphery 828 of the support member 82 recognized by the outer periphery recognition section 90 and recognizes the center of the workpiece 80 based on the outer periphery 807 of the workpiece 80 recognized by the outer periphery recognition section 90, a setting section 94 that sets whether the center of the holding surface 302 is made to coincide with the center of the support member 82 or the center of the holding surface 302 is made to coincide with the center of the workpiece 80 when the workpiece 8 is held on the holding surface 302, and a control section 9 that controls at least the conveying section 5, i.e., the robot 50 and the loader arm 52, in order to hold the workpiece 8 on the holding surface 302 in accordance with the setting of the setting section 94.

[0064] In the present embodiment, the control section 9 can perform control of the entire device, i.e., can implement control of the inventive structural elements other than the conveying section 5, but can be separate from the control section that performs control of the entire device. The control section 9 has a processor that performs arithmetic processing according to a control program, a storage medium such as a memory, and the like, and is electrically connected to the robot 50 of the conveying section 5, the loader arm 52 of the conveying section 5, the holding surface rotating section 36, the temporary placement table rotating section 118, and the like via a communication path not shown that is wired or wireless, and control of the workpiece 8 removal operation from the first cassette 21 by the robot 50 and control of the workpiece 8 insertion operation into the second cassette 22 after grinding, control of the workpiece 8 conveying operation from the temporary placement table 11 to the chuck table 30 by the loader arm 52, control of the rotation operation of the chuck table 30 that holds the workpiece 8 by suction, and control of the rotation operation of the temporary placement table 11 by the temporary placement table rotating section 118, and the like are performed by the control section 9.

[0065] In the present embodiment, for example, the outer periphery recognizing section 90, the center recognizing section 92, and the setting section 94 are included in the control unit 9. The setting section 94 is set, for example, to a region of a storage medium of the control unit 9. The grinding device 1 has, for example, a touch panel or the like, which is not shown, as an input unit for the operator to input machining conditions and the like to the grinding device 1. When the grinding device 1 is used to perform grinding machining on the bonded workpiece 8, in a case where the operator inputs various kinds of information of machining conditions (grinding feed speed of the grinding unit 16, rotational speed of the chuck table 30, and the like) corresponding to the kind of the workpiece 80 and the like from the input unit to the grinding device 1, in a case where the bonded workpiece 8 is held to the holding surface 302 of the chuck table 30, for example, when the case where the center of the holding surface 302 is made to coincide with the center of the support member 82 is selected and input, the selection result is set and stored in the setting section 94.

[0066] The program describing the outer periphery recognizing process is stored in the storage medium of the control unit 9, and when the photographed image data is sent from the camera 142 of the photographing unit 14, the outer periphery recognizing section 90 reads out and executes the program describing the outer periphery recognizing process from the storage medium. The program describing the center recognizing process is stored in the storage medium of the control unit 9, and when the outer periphery recognizing section 90 recognizes the outer periphery 807 of the workpiece 80 and recognizes the outer periphery 828 of the support member 82, the center recognizing section 92 reads out and executes the program describing the center recognizing process from the storage medium.

[0067] Next, the grinding method of the present application will be described with reference to the grinding device 1 of the present application shown in FIG. 1. Figure 1 In the present embodiment, when the operator sets the machining conditions of the grinding device 1 before starting the grinding machining, in a case where the center of the workpiece 80 and the center of the support member 82 are deviated in the bonded workpiece 8, the case where the center of the holding surface 302 of the chuck table 30 is made to coincide with the center of the support member 82 is not selected, but the case where the center of the holding surface 302 of the chuck table 30 is made to coincide with the center of the workpiece 80 is selected to set the setting section 94.

[0068] In addition, in a case where a mark indicating the crystal orientation is formed on the workpiece 80 itself, the setting section 94 can be set in a manner that the center of the holding surface 302 of the chuck table 30 is made to coincide with the center of the support member 82.

[0069] (1) Carrying-out of the bonded workpiece 8 from the first cassette 21

[0070] For example, the robot hand 500 of the robot 50 is positioned at the height position of the workpiece 80 of the target in the 1st box 21. For example, in the 1st box 21, the ground surface 802 of the workpiece 80 is oriented upward, and the outer peripheral portion of the support member 82 is supported on the shelf. Also, for example, the suction surface 5004 of the robot hand 500 is set in a state of being oriented upward (+Z direction side).

[0071] The robot hand 500 is rotated to enter a predetermined position inside the 1st box 21 from the opening of the 1st box 21, for example, to position the robot hand 500 in a manner such that the center of the robot hand 500 substantially coincides with the center of the support member 82. Next, the robot hand 500 is raised to cause the suction surface 5004 to contact the back surface 822 oriented downward of the support member 82 from the lower side to perform suction and holding, and further, the robot hand 500 is raised until the outer peripheral portion of the support member 82 is slightly separated from the shelf.

[0072] Further, the robot hand 500 to which the fitted workpiece 8 is suction and held is withdrawn from the 1st box 21. In addition, the robot hand 500 can also abut the suction surface 5004 from the upper side against the fitted workpiece 8 to suction and hold the workpiece 80 of the workpiece 8.

[0073] (2-1) First embodiment of the photographing process

[0074] Next, a photographing process of photographing the workpiece 8 in a manner such that the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 are included is performed using the camera 142. The photographing process described below is a photographing process of the first embodiment, and includes a temporary placement process of causing the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 to protrude from the temporary placement table 11 to temporarily place the fitted workpiece 8 on the temporary placement table 11.

[0075] Specifically, the robot 50 constituting the conveyance unit 5 moves the fitted workpiece 8 above the temporary placement table 11 to substantially coincide the center of the robot hand 500 with the center of the temporary placement table 11. Then, the robot 50 places the fitted workpiece 8 on the temporary placement table 11 in a manner such that the back surface 822 of the support member 82 is oriented downward. That is, the robot hand 500 is lowered to place the fitted workpiece 8 on the temporary placement table 11 in a manner such that the temporary placement table 11 enters the U-shaped opening portion of the robot hand 500. Then, as shown in Figure 2 the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 are caused to protrude from the temporary placement table 11 to temporarily place the fitted workpiece 8 on the temporary placement table 11 to perform suction and holding. After that, the robot hand 500 retreats from the fitted workpiece 8.

[0076] like Figure 2 As shown, the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82, which are temporarily placed on the temporary worktable 11, are positioned between the camera 142 and the illumination unit 141. Furthermore, for example, the focus of the camera 142 is aligned with the upper surface of the workpiece 8, thus including the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 within the shooting area of ​​the camera 142. The illumination unit 141 is illuminated, illuminating light (e.g., visible light) upwards. A portion of this illumination light passes through the support member 82 (which is a transparent or semi-transparent component) and the workpiece 80 (which is a transparent or semi-transparent component), becoming transmitted light, and is received by the light-receiving element through the optical system of the camera 142, forming... Figure 3 The first captured image 40 is shown.

[0077] The first captured image 40 is, for example, a collection of 256 pixels of a predetermined size, each with a brightness value of 8-bit grayscale, i.e., 0 to 255. The brightness value of each pixel in the first captured image 40 is determined by the amount of light incident on each pixel of the light-receiving element of the camera 142.

[0078] The illumination light emitted by the illumination unit 141 is weakened by absorption by the support member 82, which is a transparent or semi-transparent component, and further weakened by absorption by the workpiece 80, which is also a transparent or semi-transparent component on the support member 82. That is, for... Figure 3 The light-receiving element corresponding to the support member 82 shown has a large amount of incident light, and this pixel becomes Figure 3 The gray area in the first captured image 40 indicates a low amount of incident light on the light-receiving element corresponding to the workpiece 80. The brightness value of this pixel is lower compared to the pixel representing the support member 82, becoming... Figure 3 The darker gray in the first captured image 40 is closer to black.

[0079] Camera 142 will capture Figure 3 The first captured image 40, showing the outer periphery 807 of the workpiece 80, the outer periphery 828 of the support member 82, and the space 400 (diffuser plate 400) outside the support member 82, is sent to the workpiece 8. Figure 1 The control unit 9 is shown. The first captured image 40 is stored in the storage medium of the control unit 9.

[0080] For example, Figure 2The temporary placement table 11 is rotated to change the position of the outer peripheral portion of the bonded workpiece 8 relative to the fixed camera 142. Also, the same photographed image of the bonded workpiece 8 held by the temporary placement table 11 is photographed at a plurality of positions (for example, two other positions separated from the first photographed position in the circumferential direction of the bonded workpiece 8) by the camera 142. That is, a second photographed image and a third photographed image of the bonded workpiece 8, which photograph the outer periphery 807 of the workpiece 80, the outer periphery 828 of the support member 82, and the space 400, are further formed, and stored in the storage medium of the control unit 9.

[0081] (2-2) Second Embodiment of the Photographing Process

[0082] In the photographing process, the photographing process of the second embodiment shown below can be implemented instead of the photographing process of the first embodiment described above. In the photographing process of the second embodiment, the camera 142 photographs the workpiece 8 in a manner that includes the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 of the bonded workpiece 8 held by the conveyance unit 5 shown in the photographing process of the first embodiment. Figure 1 The bonded workpiece 8 is conveyed to the holding surface 302 of the chuck table 30 by the conveyance unit 5 shown in the photographing process of the first embodiment.

[0083] Specifically, for example, under the control of the control unit 9 over the conveyance unit 5, the robot 50 that has conveyed the bonded workpiece 8 out of the first cassette 21 with the workpiece 80 oriented upward does not hand over the bonded workpiece 8 to the loading arm 52 via the temporary placement table 11.

[0084] As shown in the photographing process of the first embodiment, the loading arm 52 holds the bonded workpiece 8 by adsorbing the ground surface 802 of the workpiece 80. Figure 4 After the robot 50 that has handed over the bonded workpiece 8 to the loading arm 52 retreats from below the bonded workpiece 8, the loading arm 52 moves the bonded workpiece 8 in rotation and vertically, and positions the bonded workpiece 8 at a position where the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 of the bonded workpiece 8 enter between the camera 142 and the illumination unit 141.

[0085] Subsequently, the imaging unit 14 performs imaging of the workpiece 8 in roughly the same manner as in the first embodiment. That is, along with the movement of the workpiece 80 achieved by the loading arm 52, a first, a second, and a third image are formed, capturing the outer periphery 807 of the workpiece 80, the outer periphery 828 of the support member 82, and the workpiece 8 in the space 400. Alternatively, in the imaging process of the second embodiment, the camera 142 may also be used to image the workpiece 8 in a manner that includes the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 held by the robot 50.

[0086] (3) Peripheral identification process

[0087] For example, after performing the imaging process of the first embodiment (or the second embodiment), the following peripheral recognition process is performed: Figure 1 The peripheral identification unit 90 shown is based on the image captured during the imaging process. Figure 3 The outer periphery 828 of the support member 82 and the outer periphery 807 of the workpiece 80 are identified by the brightness difference of adjacent pixels in the first captured image 40 shown.

[0088] The peripheral recognition unit 90 displays, for example, on an imaginary output screen (the vertical coordinate plane of the X and Y axes) with a specified resolution. Figure 3 The first captured image 40 is shown. Furthermore, the peripheral recognition unit 90 determines the peripheral 828 of the support member 82 and the peripheral 807 of the workpiece 80 based on the brightness difference between adjacent pixels of the first captured image 40, and identifies their respective X-axis coordinates X1 and X-axis coordinates X2.

[0089] In addition, Figure 3 In the first captured image 40 shown, it is shown that the outer periphery 828 of the support member 82, which is the boundary portion between the support member 82 and the space 400, and the outer periphery 807 of the workpiece 80, which is the boundary portion between the support member 82 and the workpiece 80, can be captured in a manner in which each pixel is neatly arranged in the Y-axis direction without jumping out in the +X direction. However, there are also cases where each pixel jumps out in the +X direction to form the first captured image. That is, sometimes in the boundary portion (in Figure 3 The captured image is formed by mixing pixels with different brightness in the pixel column from the +X direction to the 12th column.

[0090] In this case, for example, the peripheral recognition unit 90 determines, in the first captured image 40 displayed on the output screen, the temporary boundary portion between the space 400 and the outer periphery 828 of the support member 82 (in... Figure 3The middle column represents the pixel column from the +X direction to the 12th column. Furthermore, it is also possible to calculate the brightness value of the space 400 representing this temporary boundary portion (in...). Figure 1 The number of pixels (white in the middle) in the Y-axis direction is calculated, and the brightness value of the outer periphery 828 of the support member 82 in the boundary portion is calculated (in... Figure 3 The number of pixels (in light gray) in the Y-axis direction is used to determine the number of pixels in the 12th column. If the calculated number of pixels representing space 400 is greater than the calculated number of pixels representing the outer perimeter 828 of the support member 82, then the 12th column of pixels represents space 400. If the calculated number of pixels representing space 400 is less than the calculated number of pixels representing the outer perimeter 828 of the support member 82, then the 12th column of pixels represents the outer perimeter 828 of the support member 82.

[0091] For example, Figure 1 The peripheral identification section 90 shown is selected. Figure 3 In the first captured image 40, one pixel in the Y-axis direction of the X-axis coordinate X1 of the outer periphery 828 of the support member 82 is identified as the edge coordinates (X1, Y1) for identifying the center of the support member 82 in the center identification process described later, and stored in the storage medium of the control unit 9. Additionally, the outer periphery identification unit 90 selects one pixel in the Y-axis direction of the X-axis coordinate X2 of the outer periphery 807 of the workpiece 80 in the first captured image 40, identifies the X-axis coordinates (X2, Y2) of this pixel as the edge coordinates (X2, Y2) for identifying the center of the workpiece 80 in the center identification process described later, and stores it in the storage medium of the control unit 9.

[0092] Such Figure 1 The peripheral identification unit 90 shown also performs the discrimination and identification of the outer periphery 828 of the support member 82 and the outer periphery 807 of the workpiece 80 by taking two (not shown) images of two points separated in the circumferential direction of the workpiece 80, representing the outer periphery 828 of the support member 82 and the outer periphery 807 of the workpiece 80. That is, the other two (not shown) edge coordinates of the support member 82 and the other two (not shown) edge coordinates of the workpiece 80 are stored in the storage medium of the control unit 9. Alternatively, the peripheral identification unit 90 may select two (not shown) edge coordinates other than the edge coordinates (X1, Y1) used to identify the center of the support member 82, and two (not shown) edge coordinates other than the edge coordinates (X2, Y2) used to identify the center of the workpiece 80, based on the first image 40, instead of using the second and third images.

[0093] Additionally, as explained below, the peripheral recognition unit 90 can also recognize the outer periphery 828 of the support member 82 and the outer periphery 807 of the workpiece 80 based on the first captured image 40. For example, in Figure 3 In the first captured image 40 shown, 10 pixels representing the support member 82, arranged continuously along the X-axis, are identified as an object and grouped into one. The difference in brightness values ​​of the pixels symmetrically arranged along the X-axis from the outside to the center of the 10 pixels in the first group are calculated. That is, when the 10 pixels in the first group are designated as the 1st, 2nd, 9th, and 10th pixels from the +X direction side, a total of 5 brightness differences are calculated: the brightness difference between the 1st and 10th pixels, the brightness difference between the 2nd and 9th pixels, the brightness difference between the 3rd and 8th pixels, the brightness difference between the 4th and 7th pixels, and the brightness difference between the 5th and 6th pixels. As an example, if the brightness value of the 1st pixel is 255 and the brightness value of the 10th pixel is 255, then the brightness difference between the 1st and 10th pixels is 0.

[0094] Furthermore, the sum of the five calculated brightness differences is used as the group value for Group 1. This group value represents the brightness of the central pixel of an adjacent group of 10 pixels. For example, the group value for Group 1 is 0.

[0095] Similarly, from the first group toward the central side of the support member 82, that is, at Figure 3 The first 10 pixels (the second pixel in the first group) that are offset by one pixel in the -X direction are identified as the second group. The group value of the second group is calculated in the same way as the group value of the first group. Then, the group values ​​of the third group, the fourth group, the fifth group, etc., are calculated sequentially from the outer periphery of the support member 82 toward the center.

[0096] Furthermore, the peripheral identification unit 90 was manufactured. Figure 5 The curve G1 shown uses the calculated group values ​​of group 1, group 2, group 3, etc., as the vertical axis and sets the horizontal axis as... Figure 3 The position of the group in the X-axis direction of the first captured image 40 is shown. Then, as shown in graph G1, for example, if the group value of the 7th group = 255 changes to the group value of the 8th group = -255, it is considered a large fluctuation in the group value. The 8th group with the large fluctuation in group value is... Figure 3 The X-axis coordinate position is defined as the edge coordinate representing the outer perimeter 807 of the workpiece 80. That is, the group value is defined as the brightness value of the central pixel within 10 pixels, and the difference in brightness values ​​between adjacent pixels is defined as the edge coordinate. For example, the group value is set to the brightness value of the 5th pixel.

[0097] (4) Center identification process

[0098] Next, through Figure 1 The center identification unit 92 shown performs the following center identification process: it identifies the center of the support member 82 based on the outer periphery 828 of the support member 82 identified by the outer periphery identification process, and identifies the center of the workpiece 80 based on the outer periphery 807 of the workpiece 80 identified by the outer periphery identification process. The center identification process is performed by conventional geometric calculation processing based on the edge coordinates of three points.

[0099] That is, based on the three edge coordinates (X1, Y1) of the support member 82 that is temporarily placed on the temporary worktable 11 and fits the workpiece 8, a first imaginary line connecting the edge coordinates (X1, Y1) and the second edge coordinate of the support member 82 is defined on the virtual screen, and a second imaginary line connecting the edge coordinates (X1, Y1) and the third edge coordinate of the support member 82 is defined. The intersection of the first perpendicular line passing through the midpoint of the first imaginary line and the second perpendicular line passing through the midpoint of the second imaginary line is identified as the center 829 of the support member 82 (refer to...). Figure 2 The center identification unit 92 uses three edge coordinates (X2, Y2) about the workpiece 80 to perform the same operation as identifying the center of the support member 82, thereby identifying the center 809 of the workpiece 80 (see reference). Figure 2 ).

[0100] (5) Holding process

[0101] As mentioned above, for example, after identifying Figure 2 After the temporary worktable 11 holds the center 829 of the support member 82 that is in contact with the workpiece 8 and the center 809 of the workpiece 80, the support member 82 that is in contact with the workpiece 8 is held on the holding surface 302 of the holding unit 3. In the holding process, the holding is selectively performed in the case where the center of the holding surface 302 is aligned with the center 829 of the identified support member 82, and in the case where the center of the holding surface 302 is aligned with the center 809 of the identified workpiece 80.

[0102] In this embodiment, since the operator checks the process before processing begins... Figure 1The illustrated setting section 94 sets the center of the holding surface 302 of the chuck table 30 to coincide with the center 809 of the processed object 80 of the adhered processed object 8, and thus performs the holding operation in such a manner that the center of the holding surface 302 coincides with the recognized center 809 of the processed object 80 under the control of the control unit 9. In addition, in the present embodiment, the support member 82 is formed with a mark 825 indicating the crystal orientation of the processed object 80, the holding surface 302 of the holding unit 3 is the same shape as the support member 82 in plan view, and has a corresponding mark 304 that is a flat notch, and thus the control unit 9 also performs control to control the holding surface rotation unit 36 so that the mark 825 of the support member 82 of the adhered processed object 8 held by the loading arm 52 of the conveyance unit 5 coincides with the corresponding mark 304 corresponding to the mark 825 formed on the holding surface 302.

[0103] Specifically, for example, in Figure 2 On the illustrated temporary holding table 11, the mark 825 of the support member 82 is recognized from a captured image of the adhered processed object 8 by the capturing unit 14 by the outer periphery recognition section 90 of the control unit 9. Further, the temporary holding table 11 that is holding the adhered processed object 8 by suction is rotated by a predetermined angle under the control of the control unit 9 of the motor 1181 of the temporary holding table rotation unit 118, and the mark 825 of the support member 82 is positioned in a predetermined direction.

[0104] Further, the control unit 9 controls the loading arm 52 of the conveyance unit 5, for example, so as to position the conveyance pad 520 above the processed object 80 in such a manner that the center 809 of the ground surface 802 of the processed object 80 facing upward on the temporary holding table 11 (refer to Figure 2 ) coincides with the center of the conveyance pad 520. Next, the conveyance pad 520 is lowered to come into contact with the ground surface 802 of the processed object 80, and the processed object 80 is held by suction. Next, the conveyance pad 520 is raised, and the processed object 80 is conveyed out from the temporary holding table 11.

[0105] Figure 1The position of the mark 825 on the circumference of the support member 82 when the workpiece 80 is held by the loading arm 52 is already recognized by the control unit 9 when the workpiece 80 is held and carried out from the temporary holding table 11, and therefore the chuck table 30 is rotated by a predetermined angle under the control of the control unit 9 over the holding surface rotation unit 36, and the alignment is performed so as to make the position of the mark 825 of the workpiece 8 coincide with the corresponding mark 304 of the chuck table 30. Then, the workpiece 8 is placed on the holding surface 302 in a state in which the ground surface 802 of the workpiece 80 faces upward in such a manner that the center of the holding surface 302 of the chuck table 30 coincides with the center of the carrying pad 520. The workpiece 8 is held by the loading arm 52 in such a manner that the center 809 of the workpiece 80 coincides with the center of the carrying pad 520, and therefore the center of the holding surface 302 coincides with the center 809 of the workpiece 80. In addition, the corresponding mark 304 formed on the holding surface 302 coincides with the mark 825 of the support member 82. Furthermore, the support member 82 side of the workpiece 8 is suction-held by the holding unit 3 by transmitting the suction force generated by a not-shown suction source to the holding surface 302.

[0106] (6) Grinding process

[0107] After the holding process is performed in the case in which the center of the holding surface 302 of the chuck table 30 is made to coincide with the center 809 of the workpiece 80 of the workpiece 8 is selected, a not-shown table moving mechanism moves the chuck table 30 in the +Y direction. Furthermore, the chuck table 30 holding the workpiece 8 is positioned the workpiece 80 in such a manner that the rotation center of the grinding wheel 164 of the grinding unit 16 is offset by a predetermined distance in the horizontal direction with respect to the rotation center 809 of the workpiece 80 and the rotation locus of the grinding tool 1640 passes through the rotation center 809 of the workpiece 80.

[0108] Furthermore, the grinding unit 16 is carried in the -Z direction by the grinding feed mechanism 19, and the ground surface 802 of the workpiece 80 held by the chuck table 30 is ground by the abutment of the rotating grinding tool 1640. In addition, the workpiece 80 on the holding surface 302 also rotates in conjunction with the rotation of the chuck table 30 at a predetermined rotation speed by the holding surface rotation unit 36, and therefore the entire ground surface 802 of the workpiece 80 is ground by the grinding tool 1640. In the grinding, grinding water is supplied to the contact site of the grinding tool 1640 and the ground surface 802 of the workpiece 80, and the contact site is cooled and washed.

[0109] In the grinding process, the thickness of the workpiece 80 is measured in order by the thickness measuring unit 38. Then, after the grinding unit 16 is separated by rising from the workpiece 80 that has been normally ground to the finished thickness, the chuck table 30 is moved to the vicinity of the unloading arm 132 by a table moving mechanism not shown in the drawing, in the -Y direction.

[0110] (7) Operation after grinding of the workpiece 80

[0111] Next, the unloading arm 132 suction-holds the ground surface 802 of the workpiece 8 and carries the workpiece 8 from the chuck table 30 to the rotary table 120. Next, the cleaning nozzle 121 is moved in rotation in a manner that reciprocates above the workpiece 80 at a prescribed angle, and sprays cleaning water toward the workpiece 80 below, and the rotary table 120 that suction-holds the workpiece 8 is rotated at a prescribed rotation speed, and cleaning water is supplied to the entire ground surface 802 of the workpiece 80, and thus cleaning is performed.

[0112] After the workpiece 8 is cleaned and dried in the cleaning unit 12, the robot 50 carries the workpiece 8 out of the cleaning unit 12 and stores it in the second cassette 22.

[0113] As described above, the grinding method of the workpiece 8 of the present application has a photographing process that photographs the workpiece 8 in a manner that includes the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82, using the camera 142, before the holding process, an outer periphery recognizing process that respectively recognizes the outer periphery 828 of the support member 82 and the outer periphery 807 of the workpiece 80, from the difference in brightness of pixels that are adjacent to each other in the photographed image photographed by the photographing process, and a center recognizing process that recognizes the center 829 of the support member 82 from the outer periphery 828 of the support member 82 recognized by the outer periphery recognizing process, and recognizes the center 809 of the workpiece 80 from the outer periphery 807 of the workpiece 80 recognized by the outer periphery recognizing process, and thus, in the holding process, it is possible to selectively perform the case where the center of the holding surface 302 is made to coincide with the center 829 of the support member 82 and holding is performed, and the case where the center of the holding surface 302 is made to coincide with the center 809 of the workpiece 80 and holding is performed, and furthermore, it is possible to grind the workpiece 80 in the grinding process.

[0114] As with the photographing process of the first embodiment, the photographing process includes a temporary placement process of protruding the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 from the temporary placement table 11 and temporarily placing the laminated workpiece 8 on the temporary placement table 11, irradiating light from the lower side of the laminated workpiece 8 to the upper side using the illumination section 141 disposed on the lower side of the temporarily placed laminated workpiece 8, and photographing the laminated workpiece 8 in a manner of including the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 using the camera 142 disposed opposite the illumination section 141, whereby the photographed image required in the outer periphery recognition process performed after the photographing process can be easily obtained.

[0115] As with the photographing process of the second embodiment, in the photographing process, the laminated workpiece 8 is photographed in a manner of including the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 of the laminated workpiece 8 held by the loading arm 52 of the conveyance unit 5 or the robot 50 using the camera 142, whereby the photographed image required in the outer periphery recognition process performed after the photographing process can be easily obtained.

[0116] In addition, as described above, the grinding device 1 of the present application that grinds the laminated workpiece 8 has an outer periphery recognition section 90 that recognizes the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 by discriminating from the photographed image of the laminated workpiece 8 including the outer periphery 807 of the workpiece 80 and the outer periphery 828 of the support member 82 before the laminated workpiece 8 is held by the holding surface 302 of the holding unit 3, a center recognition section 92 that recognizes the center 829 of the support member 82 from the outer periphery 828 of the support member 82 recognized by the outer periphery recognition section 90 and recognizes the center 809 of the workpiece 80 from the outer periphery 807 of the workpiece 80 recognized by the outer periphery recognition section 90, a conveyance unit 5 that conveys the laminated workpiece 8 to the holding surface 302 and holds it, a setting section 94 that sets whether the center of the holding surface 302 is made to coincide with the center 829 of the support member 82 or the center 809 of the workpiece 80 when the laminated workpiece 8 is held on the holding surface 302, and a control unit 9 that controls at least the conveyance unit 5 in order to hold the laminated workpiece 8 on the holding surface 302 in accordance with the setting of the setting section 94, whereby it is possible to selectively implement the case of holding with the center of the holding surface 302 coinciding with the center 829 of the support member 82 and the case of holding with the center of the holding surface 302 coinciding with the center 809 of the workpiece 80, and it is possible to grind the workpiece 80 thereafter.

[0117] A mark 825 indicating the crystal orientation of the workpiece 80 is formed on the support member 82, the holding surface 302 of the holding unit 3 has the same shape as the support member 82 in plan view, the holding unit 3 has a holding surface rotation unit 36 that rotates the holding surface 302 about the center of the holding surface 302, and the control unit 9 controls the holding surface rotation unit 36, whereby the control unit 9 can align the mark 825 of the support member 82 of the workpiece 8 held by the carrying unit 5 with the corresponding mark 304 corresponding to the mark 825 formed on the holding surface 302, and then, by performing grinding, the workpiece 80 can be thinned to a uniform thickness.

[0118] The grinding method of the workpiece according to the present application is not limited to the above-described embodiment, and of course can be implemented in various different ways within the scope of the technical idea thereof. In addition, the structure of the grinding device 1 and the like illustrated in the drawings are not limited thereto, and can be appropriately changed within a range in which the effects of the present application can be exerted.

Claims

1. A grinding method for bonding a workpiece, comprising grinding a workpiece formed by bonding at least two components: a semi-transparent, circular plate-shaped workpiece and a transparent or semi-transparent, circular plate-shaped support member extending outward from the outer periphery of the workpiece, using an abrasive tool, wherein... The grinding method for conforming to the workpiece has the following steps: The photographing process involves using a camera to photograph the workpiece in a manner that includes the outer periphery of the workpiece and the outer periphery of the supporting component; The peripheral identification process identifies the peripherals of the support component and the workpiece by means of the brightness difference between adjacent pixels in the image captured by the imaging process. The center identification process identifies the center of the support member based on the outer periphery of the support member identified by the outer periphery identification process, and identifies the center of the workpiece based on the outer periphery of the workpiece identified by the outer periphery identification process. The holding process, after the center identification process, holds the support member conforming to the workpiece on the holding surface of the chuck table; and The grinding process involves using an abrasive to grind the workpiece that has been held in place by the holding process. In this holding process, after selectively holding the workpiece with the center of the holding surface aligned with the center of the support member and holding it with the center of the holding surface aligned with the center of the workpiece, the workpiece is ground by the grinding process.

2. The grinding method for conforming to the workpiece according to claim 1, wherein, The shooting process includes the following temporary placement process: extending the outer periphery of the workpiece and the outer periphery of the supporting component from the temporary placement worktable and temporarily placing the workpiece on the temporary placement worktable. In the shooting process, a lighting unit disposed below the workpiece being bonded is used to illuminate the workpiece from below, and a camera disposed opposite the lighting unit is used to photograph the workpiece in a manner that includes the outer periphery of the workpiece and the outer periphery of the support member.

3. The grinding method for conforming to the workpiece according to claim 1, wherein, In the shooting process, the camera is used to photograph the workpiece, including the outer periphery of the workpiece held by the conveying unit that transports the workpiece to the holding surface and the outer periphery of the support member.

4. A grinding apparatus, wherein, This grinding device has the following features: A chuck table holds a workpiece by means of a retaining face that holds at least two parts together, namely a workpiece that is plate-shaped and semi-transparent and a support member that is plate-shaped and transparent or semi-transparent and protrudes outward from the outer periphery of the workpiece. A grinding unit that uses a grinding wheel to grind the workpiece held by the holding surface in contact with the workpiece. The conveying unit conveys the workpiece to the holding surface of the chuck table and holds it there. A camera, which photographs the workpiece being fitted; and The control unit controls at least the chuck table, the grinding unit, the conveying unit, and the camera. The control unit includes: The peripheral identification unit identifies the outer periphery of the workpiece and the outer periphery of the support member by determining based on an image of the workpiece including the outer periphery of the workpiece and the outer periphery of the support member before holding the workpiece with the holding surface of the chuck table. A center identification unit identifies the center of the support member based on the outer periphery of the support member identified by the outer periphery identification unit, and identifies the center of the workpiece based on the outer periphery of the workpiece identified by the outer periphery identification unit; and The setting unit determines whether, when the workpiece is held on the holding surface of the chuck table, the center of the holding surface coincides with the center of the support member, or the center of the holding surface coincides with the center of the workpiece. The control unit controls the conveying unit so that the workpiece is held on the holding surface of the chuck table according to the setting of the setting unit.

5. The grinding apparatus according to claim 4, wherein, The support component has markings indicating the crystal orientation of the workpiece. The retaining surface of the chuck table has the same shape as the support component when viewed from above. The chuck table includes a retaining surface rotation unit that rotates the retaining surface about its center. The control unit controls the rotating unit of the holding surface so that the mark on the support member of the workpiece held by the conveying unit matches the corresponding mark formed on the holding surface.

Images