Wafer manufacturing device and grinding device

Abstract

To detect residual resin after grinding to manufacture wafers with uniform thickness in a wafer manufacturing method in which both sides of sliced wafers are ground to manufacture the wafers.SOLUTION: A wafer manufacturing method includes a resin layer forming step (step S1) of forming a resin layer on one side of a sliced wafer sliced from an ingot, a holding step (step S2) of holding the resin layer side on a chuck table, a first grinding step (step S3) of grinding the other side, a resin layer peeling step (step S4) of peeling the resin layer from the one side, and a second grinding step (step S8) of grinding the one side, and a resin remaining detection step (step S5) of detecting the presence or absence of resin on the outer periphery of the sliced wafer is performed between the resin layer peeling step and the second grinding step.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a wafer manufacturing method and a grinding apparatus. [Background technology]

[0002] When wafers are manufactured by grinding both sides of a wafer sliced ​​from an ingot (slice wafer) as disclosed in Patent Document 1 and Patent Document 2 below, a resin layer is formed on the entire surface of one side of the sliced ​​wafer as disclosed in Patent Document 3 below, the resin layer side is held on a chuck table, and the exposed other side is ground with a grinding wheel, and then, as disclosed in Patent Document 4 below, the resin layer is peeled off and one side is ground to form a wafer of a predetermined thickness.

[0003] When this resin layer is peeled off, some resin may remain, so as disclosed in Patent Document 5 below, the resin remaining on the wafer at the time of peeling is removed by cleaning with a cleaning mechanism. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-151099 A [Patent Document 2] JP 2011-249652 A [Patent Document 3] JP 2017-224670 A [Patent Document 4] JP 2017-224671 A [Patent Document 5] JP 2011-151099 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, because the system did not detect the resin remaining on the wafer after cleaning, if the resin could not be completely removed by cleaning, resin could get caught between one side of the wafer and the top surface of the chuck table when the other side is ground, which would result in the wafer not being able to have a uniform thickness.

[0006] Therefore, in a wafer manufacturing method in which both sides of a sliced ​​wafer are ground to manufacture the wafers, there is a problem to be solved as to how to detect the resin remaining after grinding and to manufacture wafers of a uniform thickness. [Means for solving the problem]

[0007] The wafer manufacturing method of the present invention is a wafer manufacturing method for manufacturing wafers by grinding both sides of sliced ​​wafers sliced ​​from an ingot, the method including a resin layer forming step of forming a resin layer covering the entire one side of the sliced ​​wafer, a first holding step of holding the sliced ​​wafer on a chuck table via the resin layer, a first grinding step of grinding the other side of the sliced ​​wafer with a grinding wheel, a resin layer peeling step of peeling the resin layer from the one side of the sliced ​​wafer after the first grinding step, and a grinding step of grinding the one side of the sliced ​​wafer after the resin layer peeling step. and a second grinding step of grinding the first surface of the sliced ​​wafer with a grinding wheel, and a resin remaining detection step of detecting the presence or absence of resin on the outer periphery of the sliced ​​wafer after the resin layer peeling step and before the start of the second grinding step, the resin remaining detection step comprising an imaging step of irradiating light onto the first surface of the sliced ​​wafer and capturing an image of the first surface with a camera, a binarization step of binarizing the image captured in the imaging step at a predetermined brightness, and a determination step of determining that there is resin remaining if the range of white color in the binarized image binarized in the binarization step is equal to or exceeds a predetermined range. Further, the grinding device of the present invention is a grinding device used in the above-mentioned wafer manufacturing method, and includes a chuck table that holds the sliced ​​wafer on a holding surface, a grinding unit that grinds the sliced ​​wafer held on the chuck table with a grinding wheel, an imaging unit that projects light onto the outer circumferential edge of the sliced ​​wafer to capture an image, and a resin detection section that detects resin adhering to the sliced ​​wafer from the image captured by the imaging unit. Effect of the Invention

[0008] In this wafer manufacturing method, since a resin remaining detection step is performed after the resin layer peeling step and before the second grinding step, if the resin is not completely removed in the resin peeling step and remains on the outer periphery of one side of the sliced ​​wafer, the resin can be detected. Therefore, it becomes possible to remove the resin, and it becomes possible to avoid the problem that the remaining resin is caught between the chuck table of the grinding device and the wafer after grinding cannot be formed to a uniform thickness.

[0009] Since the present grinding apparatus is equipped with a resin detection unit, it is possible to detect the adhesion of resin to the sliced ​​wafers after grinding one side of the sliced ​​wafers and before grinding the other side. [Brief description of the drawings]

[0010] [Figure 1] 1 is a perspective view showing a wafer manufacturing apparatus according to an embodiment; [Diagram 2] FIG. 2 is a perspective view showing an example of a wafer. [Diagram 3] 1 is a flow chart showing the steps of a wafer manufacturing method. [Figure 4] FIG. 2 is a perspective view showing an example of a resin layer forming device constituting a wafer manufacturing apparatus. [Diagram 5] FIG. 2 is a cross-sectional view showing a wafer provided with a protective member. [Figure 6] FIG. 2 is a perspective view showing a transfer cassette constituting the wafer manufacturing apparatus. [Figure 7]FIG. 2 is a perspective view showing an example of a grinding device constituting the wafer manufacturing apparatus. [Figure 8] FIG. 1 is a perspective view showing a configuration of a separation device included in a wafer manufacturing apparatus; [Figure 9] 11 is an explanatory diagram showing a state in which the protective member is peeled off from the wafer. FIG. [Figure 10] 10(a) to (c) are explanatory views showing how the outer periphery of a sliced ​​wafer is cleaned using an outer periphery cleaning device provided in a peeling device constituting a wafer manufacturing apparatus. [Figure 11] 1A is an explanatory diagram showing how the entire surface of a sliced ​​wafer is imaged by a camera constituting the resin detection unit, and FIG. 1B is an explanatory diagram showing how a part of the outer periphery of a sliced ​​wafer is imaged by a camera constituting the resin detection unit. [Figure 12] FIG. 11 is an explanatory diagram showing an example of a captured image. [Figure 13] FIG. 2 is a vertical cross-sectional view showing an example of a peripheral cleaning device provided in the peeling device. [Figure 14] FIG. 2 is an exploded perspective view showing a first plate and a second plate that constitute a gas-liquid separator of the outer periphery cleaning device. [Figure 15] FIG. 2 is a vertical cross-sectional view showing the gas-liquid separation device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The wafer manufacturing apparatus 100 shown in FIG. 1 is an apparatus used to carry out the present wafer manufacturing method, and includes a resin layer forming apparatus 2 for forming a resin layer on one surface Wa of a sliced ​​wafer W shown in FIG. 2 sliced ​​from an ingot, a grinding apparatus 3 for grinding the sliced ​​wafer W, and a peeling apparatus 4 for peeling the resin layer from the sliced ​​wafer W. Between the resin layer forming apparatus 2 and the grinding apparatus 3, a delivery cassette unit 5 for transporting the sliced ​​wafer W from the resin layer forming apparatus 2 to the grinding apparatus 3 is disposed. The resin layer forming apparatus 2, the delivery cassette unit 5, the grinding apparatus 3, and the peeling apparatus 4 are arranged, for example, in the X-axis direction in FIG. 1. A load port LP for accommodating wafers whose both sides have been ground is provided in front of the grinding apparatus 3 (−Y direction side).

[0012] The sliced ​​wafer W is formed in a plate shape and has one surface Wa and the other surface Wb. The one surface Wa and the other surface Wb of the sliced ​​wafer W have unevenness and undulations formed when the sliced ​​wafer W was cut out from an ingot. Below, a procedure for grinding and flattening the one surface Wa and the other surface Wb of the sliced ​​wafer W will be described with reference to the flowchart of FIG.

[0013] 1. Resin layer formation process (step S1) To carry out this step, a resin layer forming apparatus 2 shown in Fig. 1 and Fig. 4 is used. As shown in Fig. 4, in the resin layer forming apparatus 2 having a housing 200, first, a first transfer robot 21 takes out one sliced ​​wafer W from a cassette 23a storing the sliced ​​wafers W, and transfers it to a first support stand 26a. Then, a wafer detection unit 27 detects the center position and orientation of the sliced ​​wafer W. Thereafter, a wafer transfer unit 25 transfers the sliced ​​wafer W from the first support stand 26a to a holding unit 250. In the holding unit 250, a holding table 252 suction-holds the other surface Wb of the sliced ​​wafer W.

[0014] In parallel with the transport of the sliced ​​wafers W to the holding unit 250, the clamp unit 232 of the sheet placement unit 230 clamps the sheet F made of a transparent material that transmits ultraviolet light and moves it in the Y-axis direction, thereby drawing out the sheet F from the roll unit 211. The sheet F is adsorbed and held on the sheet holding surface 221 of the glass stage 220.

[0015] Thereafter, the resin supply unit 240 rotates the resin supply nozzle 241 to position the supply port 243 of the resin supply nozzle 241 above the stage 220. Next, the dispenser 242 sucks up liquid resin (not shown) made of, for example, an ultraviolet curing resin contained in a resin tank (not shown) and delivers it to the resin supply nozzle 241. As a result, a predetermined amount of liquid resin is dripped from the resin supply nozzle 241 toward the sheet F that is adsorbed and held on the stage 220.

[0016] The expansion part 260 holds the support structure 251 of the holding part 250 by a lift plate 264. The expansion part 260 rotates the ball screw 261 by a motor 262, thereby lowering the holding part 250 together with the lift plate 264. As the holding part 250 descends, one surface Wa of the sliced ​​wafer W held by suction spreads the liquid resin on the sheet F held by suction on the stage 220 to a predetermined thickness.

[0017] Thereafter, the curing unit 270 irradiates ultraviolet light via the stage 220 toward the liquid resin spread by one surface Wa of the sliced ​​wafer W. As a result, the liquid resin is cured, and a resin layer R made of the liquid resin is formed to cover the entire surface of one surface Wa of the sliced ​​wafer W. The color of this resin layer R is, for example, transparent.

[0018] Thereafter, the sliced ​​wafer W is transported to the second support stand 26b by the wafer transport unit 25, and the excess sheet F is cut off by the sheet cutter 28 along the outer shape of the sliced ​​wafer W. At this time, the diameter of the sheet F is made slightly larger than the diameter of the sliced ​​wafer W. In this manner, as shown in Fig. 5, the entire surface of one side Wa of the sliced ​​wafer W is covered with the resin layer R, and the sheet F is fixed to the resin R, thereby forming a protective member P consisting of the resin R and the sheet F.

[0019] After the protective member P is formed, the first transfer robot 21 transfers the sliced ​​wafers W provided with the protective member P to the delivery cassette unit 5.

[0020] 6, the delivery cassette section 5 has a delivery cassette 510 that stores sliced ​​wafers W in a shelf-like manner, and a cassette stage 52 on which the delivery cassette 510 is placed. The delivery cassette 510 has a plurality of shelves 511 for storing sliced ​​wafers W, a first opening 512 that opens to the resin layer forming device 2 side, and a second opening 513 that opens to the grinding device 3 side, and the sliced ​​wafers W can be put in and taken out of the shelves 511 from both the resin layer forming device 2 side and the grinding device 3 side.

[0021] The first transport robot 21 of the resin layer forming apparatus 2 shown in Figure 1 stores the sliced ​​wafer W on which the resin layer has been formed on the shelf 511 of the transfer cassette 510 through the first opening 512 so that the other surface Wb faces upward.

[0022] 2. First holding step (step S2) Next, the main process is carried out in the grinding device 3 shown in FIG. 1 and FIG.

[0023] The grinding apparatus 3 is broadly divided into a loading / unloading area A at the front (-Y direction side) of the apparatus where wafers are loaded and unloaded, and a processing area B at the rear (+Y direction side) of the apparatus where wafer grinding processing is performed.

[0024] The chuck table 302 that holds the sliced ​​wafer W can move in the front-rear direction (Y-axis direction) between the loading / unloading area A and the processing area B. The loading / unloading area A is equipped with a second transport robot 22 which transports the sliced ​​wafer W from the transfer cassette section 5 and transports the sliced ​​wafer W after grinding and cleaning into the transfer cassette section 5, a temporary placement unit 32 which is disposed near the second transport robot 22 and aligns the sliced ​​wafer W at a fixed position, a spin cleaning unit 350 which cleans the wafer after grinding, a first transport unit 313a which transports the sliced ​​wafer W from the temporary placement unit 32 to the chuck table 302 located in the loading / unloading area A, a second transport unit 313b which transports the sliced ​​wafer W after grinding from the chuck table 302 located in the loading / unloading area A to the spin cleaning unit 350, and a resin detection section 360 which detects resin adhering to the sliced ​​wafer W.

[0025] The temporary placement unit 32 includes a temporary placement table 320 formed in a circular shape with a smaller diameter than the sliced ​​wafer W and on whose upper surface the sliced ​​wafer W is placed, and a positioning mechanism 321 composed of a plurality of pins arranged in an arc shape on the outer periphery of the temporary placement table 320, which moves in the radial direction of the temporary placement table 320 to position the sliced ​​wafer W at a predetermined position.

[0026] The spin cleaning unit 350 has a spinner table 352 disposed in the center, four edge clamps 351 extending radially from the spinner table 352, a rotating section 354 that rotates the spinner table 352 and the edge clamps 351, and a cleaning nozzle 353 that can rotate around the Z-axis direction as a rotation axis. The four edge clamps 351 are attached to the spinner table 352, for example, at angular intervals of approximately 90 degrees.

[0027] The resin detection unit 360 includes cameras 361 and 362 for capturing images of the sliced ​​wafers W, light-emitting units 364 arranged around the cameras 361 and 362, white backplates 369 and 370 for reflecting the light emitted from the light-emitting units 364, and an image processing unit 363 for processing the images captured by the cameras 361 and 362 to detect the presence or absence of resin. The camera 361 is disposed above the center of the temporary placement table 320, and the camera 362 is disposed above the center of the spinner table 352. The image processing unit 363 includes a CPU and a memory. Instead of the backplates 369 and 370, a white backlight may be disposed.

[0028] The processing area B is provided with a grinding unit 303 that grinds the sliced ​​wafers W held on the chuck table 302, and a grinding feed unit 306 that raises and lowers the grinding unit 303 in the Z-axis direction.

[0029] The grinding unit 303 includes a grinding wheel 334 having a grinding stone 340, a spindle 335 to the tip of which the grinding wheel 334 is attached, and a motor 336 that drives the spindle 335 to rotate.

[0030] The grinding feed unit 306 includes a ball screw 307 extending in the Z-axis direction, a pair of guide rails 308 extending in the Z-axis direction, a motor 305 for rotating the ball screw 307, a lifting plate 309 having a nut portion that screws into the ball screw 307 and is guided by the guide rails 308 to rise and fall, and a holder 337 fixed to the lifting plate 309 and supporting the grinding unit 30. The motor 305 rotates the ball screw 307 to raise and lower the grinding unit 303 supported by the holder 337.

[0031] In the grinding device 3, first, the second transfer robot 22 takes out the sliced ​​wafer W having a resin layer formed on one surface Wa from the delivery cassette unit 5 through the second opening 513. The second transfer robot 22 places the sliced ​​wafer W on the temporary placement table 320 so that the other surface Wb faces upward. Then, the positioning mechanism 321 presses the peripheral portion of the sliced ​​wafer W toward the center, thereby positioning the sliced ​​wafer W at a predetermined position.

[0032] Next, the first transport unit 313a suction-holds the other side Wb of the sliced ​​wafer W, and transports it to the chuck table 302 located in the loading / unloading area A. The chuck table 302 suction-holds the protective member P formed on one side Wb of the sliced ​​wafer W. As a result, the sliced ​​wafer W is held on the chuck table 302 via the protective member P including the resin layer R, with the other side Wb exposed.

[0033] 3. First grinding process (step S3) Next, the chuck table 302 holding the sliced ​​wafer W moves from the carry-in / out area A to below the grinding wheel 334 of the grinding unit 303 installed in the processing area B. Then, as the chuck table 302 rotates, the grinding wheel 334 having the grinding wheel 340 rotates. Furthermore, the grinding feed unit 306 feeds the grinding unit 303 downward, so that the rotating grinding wheel 340 comes into contact with and grinds the other side Wb of the sliced ​​wafer W. When the other side Wb of the sliced ​​wafer W is ground until it is flattened, the grinding feed unit 306 raises the grinding unit 303, and grinding ends.

[0034] After the grinding is completed, the chuck table 302 moves to the load / unload area A, and the second transport unit 313 b suction-holds the other surface Wb of the sliced ​​wafer W, and transports the sliced ​​wafer W to the spin cleaning unit 350.

[0035] In the spin cleaning unit 350, the spinner table 352 adsorbs and holds the protective material P covering one surface Wa of the sliced ​​wafer W transported by the second transport unit 313b. Thereafter, the rotating section 354 rotates the spinner table 352 at high speed to rotate the sliced ​​wafer W at high speed, and cleaning water is sprayed from the cleaning nozzle 353 toward the other surface Wb, thereby cleaning the other surface Wb.

[0036] After the spraying of the cleaning water is stopped, the sliced ​​wafers W are dried by maintaining high-speed rotation of the sliced ​​wafers W by the rotating part 354. At this time, high-pressure air may be sprayed toward the sliced ​​wafers W from an air nozzle (not shown). After the drying is completed, the suction of the sliced ​​wafers W by the spinner table 352 is released, and the sliced ​​wafers W are simply placed on the spinner table 352.

[0037] 4. Resin layer peeling process The sliced ​​wafer W placed on the spinner table 352 is transferred by the second transfer robot 22 to the peeling device 4 shown in FIGS.

[0038] 8, the peeling device 4 includes a holding unit 42 for holding and transporting the sliced ​​wafer W. The holding unit 42 includes a holding pad 421 for suction-holding the sliced ​​wafer W, an arm unit 420 for supporting the holding pad 421, a Z-axis direction moving unit 413 for supporting the arm unit 420 and moving it back and forth in the Z-axis direction, a movable plate 429 for supporting the Z-axis direction moving unit 413, and a Y-axis direction moving unit 412 for moving the movable plate 429 back and forth in the Y-axis direction.

[0039] In the peeling device 4, first, the holding pad 421 of the holding part 42 is moved by the Y-axis direction moving part 412 and the Z-axis direction moving part 413 to the spin cleaning unit 350 of the grinding device 3 shown in FIG. 6 adjacent to the peeling device 4. Then, the holding pad 421 adsorbs and holds the other surface Wb of the sliced ​​wafer W placed on the spin cleaning unit 350.

[0040] Thereafter, the holding unit 42 places the sliced ​​wafer W on the holding table 441 so that the other surface Wb faces upward. The holding table 441 suction-holds the sliced ​​wafer W and is rotatable about the Z-axis direction as the axis of rotation. Then, the holding table 441 and the outer portion peeling unit 443 peel off only the outer portions of the protective member P of the sliced ​​wafer W shown in FIG. 5 from one surface Wa of the sliced ​​wafer W at multiple locations (e.g., eight locations). After this peeling, the suction of the sliced ​​wafer W by the holding table 441 is released.

[0041] Next, the holder 42 sucks the sliced ​​wafer W on the holding table 441 with the holding pad 421, transports the sliced ​​wafer W to a position above the full peeling section 430, and fixes it at that position.

[0042] The full peeling section 430 includes a gripping section 431 and a moving member 432 that moves the gripping section 431 along the X-axis direction. The gripping section 431 grips the peeled outer portion of the protective member P of the sliced ​​wafer W on the -X side. In this state, the moving member 432 moves the gripping section 431 to the +X side. Since the position of the sliced ​​wafer W is fixed, the gripping section 431 gripping the protective member P moves, and the protective member P is peeled off from one surface Wa of the sliced ​​wafer W as shown in FIG. 9. The peeled protective member P falls into a box 479 shown in FIG. 8.

[0043] The peeling device 4 also includes an outer periphery cleaning device 6 for cleaning the outer periphery of the sliced ​​wafer W. The holder 42 transports the sliced ​​wafer W from which the protective member P has been peeled off to the outer periphery cleaning device 6.

[0044] 10(a), the holder 42 places the sliced ​​wafer W, which is held by suction with the holding pad 421, on the holding table 63 of the outer periphery cleaning device 6 so that the other surface Wb faces upward. The holding table 63 holds one surface Wa of the sliced ​​wafer W by suction.

[0045] Holding table 63 is supported by a movable block 64 that is movable along a guide rail 65. A cleaning box 67 is disposed at the end of guide rail 65 on the +X side. Guide rail 65 is also configured to be able to tilt in the direction of arrow C by a tilting portion 66 provided at the end of guide rail 65 on the -X side.

[0046] After the holding table 63 holds the sliced ​​wafer W, the movable block 64 supporting the holding table 63 moves in the +X direction along the guide rails 65. As a result, as shown in FIG. 10(b), the outer periphery of the sliced ​​wafer W passes through a wafer entrance 671 provided in the cleaning box 67 and is sandwiched between a pair of sponges 672 provided above and below. In this state, the holding table 63 rotates, and water is sprayed from the cleaning water nozzle 673 onto the sponge 672. As a result, the outer periphery of the sliced ​​wafer W is cleaned by the sponge 672.

[0047] The cleaning water supplied from the cleaning water nozzle 673 and absorbed by the sponge 672 seeps out from the sponge 672, drops, and accumulates in the cleaning box 67. To drain this water, the tilting portion 66 tilts the guide rail 65 in the direction in which the cleaning box 67 descends, as shown in FIG. 10(c). As a result, the cleaning water accumulated in the cleaning box 67 is discharged from a drainage outlet 674 provided on the +X direction side of the cleaning box 67. In addition, the mist of the cleaning water filling the cleaning box 67 is separated into gas and water by a gas-liquid separator 675 provided on the +X direction side of the cleaning box 67. The separated water is discharged from the drainage outlet 674, and the gas is discharged from an exhaust outlet 676.

[0048] 5. Resin Remaining Detection Process (Step S5) After the cleaning of the outer periphery of the sliced ​​wafer W is completed, the guide rail 65 is returned to the horizontal position, and the movable block 64 moves in the -X direction so that the entire sliced ​​wafer W is taken out of the cleaning box 67. Thereafter, the holding table 63 releases the suction of the sliced ​​wafer W, and the holding unit 42 of the peeling device 4 shown in Fig. 8 suction-holds the sliced ​​wafer W on the holding table 63 by means of the holding pad 421. Then, the holding unit 42 transports the sliced ​​wafer W to the grinding device 3 shown in Fig. 7, and places the sliced ​​wafer W on the spinner table 352 of the spin cleaning unit 350 thereof so that one surface Wa faces upward.

[0049] 5-1 Imaging process (step S5-1) When the sliced ​​wafer W is placed on the spinner table 352, as shown in FIG. 11(a), a plurality of light-emitting units 364 attached around the cameras 361 and 362 irradiate light toward one surface Wa of the sliced ​​wafer W, and the cameras 361 and 362 capture the reflected light to form an image showing the entire surface of the one surface Wa of the sliced ​​wafer W. Here, the light emitted by the light-emitting units 364 is, for example, green light. The wavelength of the green light is 505 to 555 nm. The color of the light is not limited to green.

[0050] 5-2 Binarization process (step S5-2) Next, in the image processing unit 363 shown in Fig. 7, the image acquired in the imaging step is subjected to binarization processing based on a predetermined brightness. An example of an image of one surface Wa of the sliced ​​wafer W after the binarization processing is shown in Fig. 12. In the binarized image 365 shown in Fig. 12, one surface Wa of the sliced ​​wafer W is displayed in black.

[0051] In the binarized image 365, residual resin 367, 368 remains on the outer periphery of one surface Wa, and because the residual resin 367, 368 is transparent, it appears white due to the backlight or the white back plate 370, and is turned white by binarization. The residual resin 367, 368 is the resin that remains because the resin R could not be completely peeled off when it was peeled off in the peeling process.

[0052] 5-3 Judgment process (step S5-3) The CPU provided in the resin detection unit 360 detects white pixels in the binarized image 365, and if the range of the white pixels is equal to or larger than a preset range, it determines that there is residual resin on the sliced ​​wafer W. The preset range is specified, for example, by the number of consecutive pixels. On the other hand, if there are no white pixels, or if there are white pixels but the range is smaller than the preset range, it is determined that there is no residual resin. The residual resin may be attached not only to one surface Wa but also to the outer peripheral side surface. Both the residual resins 367 and 368 are attached to the outer peripheral portion of the sliced ​​wafer W, but the residual resin 367 is attached to one surface Wa, and the residual resin 368 is attached by wrapping around from the outer peripheral portion to the other surface Wb. The remaining resins 367, 368 are transparent, but in this process, both the remaining resins 367, 368 can be detected as white in the binarized image 365 by reflection on the white backplate 370 or by a white backlight not shown.

[0053] If it is determined in the determination step that there is no remaining resin, the process proceeds to the second grinding step, whereas if it is determined that there is remaining resin, the resin removal step is carried out (step S6).

[0054] After the resin layer peeling step, the sliced ​​wafers W may be transferred from the spinner table 352 to the temporary placement table 320 by the second transfer robot 22, and this step may be performed using the camera 361 above the temporary placement table 320. 11(b), a configuration in which the camera 362 (361) captures an image of the outer periphery of the sliced ​​wafer W may be used. In this case, imaging and rotating the table at a predetermined angle are repeated so that a plurality of images captured by the camera 362 (361) partially overlap each other, thereby capturing an image of the entire outer periphery of the sliced ​​wafer W. The back plate 371 or a backlight (not shown) may be disposed only in a portion where light from the light emitting unit 364 is irradiated. A binarization step and a determination step are performed every time an image is captured, and if it is determined that there is residual resin, a resin removal step is performed even if the entire outer periphery of the sliced ​​wafer W has not been captured.

[0055] 6. Resin removal process (step S7) When the sliced ​​wafer W is held on the spinner table 352 and the remaining resin detection step is performed, and the remaining resin 367, 368 is detected, the spinner table 352 is rotated from the current state, and cleaning water or a two-fluid mixture of cleaning water and gas is sprayed from the cleaning nozzle 353 to remove the remaining resin 367, 368. At this time, by concentrating the cleaning nozzle 353 on the outer periphery of the sliced ​​wafer W, the resin remaining on the outer periphery can be effectively removed. If necessary, one side Wa of the sliced ​​wafer W may be sucked and held by the second transport robot 22, the sliced ​​wafer W may be turned over, and the other side Wb of the sliced ​​wafer W may be placed on the spinner table 352 with the other side Wb facing upward and sucked, and the other side Wb may be sprayed with cleaning water or a two-fluid to clean it.

[0056] On the other hand, when the remaining resin detection step is performed with the sliced ​​wafer W held on the temporary placement table 320, the second transfer robot 22 suction-holds one side Wa of the sliced ​​wafer W and transfers it to the spinner table 352, and places the other side Wb on the temporary placement table 320. Then, the spinner table 352 is rotated and cleaning water is sprayed from the cleaning nozzle 353. By positioning the cleaning nozzle 353 intensively on the outer periphery of the sliced ​​wafer W, the resin remaining on the outer periphery can be effectively removed.

[0057] 7 Second grinding process (step S8) The sliced ​​wafer W from which the resin on the outer periphery has been removed is picked up by the second transfer robot 22 at one side Wa and transferred to the temporary placement table 320, where the other side Wb is placed. Then, the positioning mechanism 321 presses the peripheral portion of the sliced ​​wafer W toward the center, thereby positioning the sliced ​​wafer W at a predetermined position.

[0058] Next, the first transfer unit 313a suction-holds one surface Wa of the sliced ​​wafer W, and transfers it to the chuck table 302 located in the load / unload area A. The chuck table 302 suction-holds the other surface Wb of the sliced ​​wafer W.

[0059] Next, the chuck table 302 holding the sliced ​​wafer W moves below the grinding wheel 334, and the chuck table 302 and the grinding wheel 334 are rotated while the grinding unit 303 including the grinding wheel 334 is lowered. As a result, the grinding stone 340 rotating together with the grinding wheel 334 comes into contact with one side Wa of the sliced ​​wafer W and grinds it. When the one side Wa is flattened and the sliced ​​wafer W is ground until it has a predetermined thickness, the grinding ends. In this process, by grinding the one side Wa, even if resin remains on the one side Wa, the resin can be removed.

[0060] After grinding is completed, the chuck table 302 moves to the load / unload area A and releases the suction of the sliced ​​wafer W. Then, the second transport unit 313b suction-holds the other surface Wb of the sliced ​​wafer W and transports the sliced ​​wafer W to the spin cleaning unit 350.

[0061] In cleaning one side Wb of the sliced ​​wafer W after grinding, the four edge clamps 351 grip the outer periphery of the sliced ​​wafer W. Then, the rotating unit 354 rotates the spinner table 352 at high speed. As a result, the edge clamps 351 attached to the spinner table 352 and the sliced ​​wafer W gripped by the edge clamps 351 also rotate at high speed. Then, cleaning water is sprayed from the cleaning nozzle 353 toward one side Wa of the sliced ​​wafer W, and cleaning water is sprayed upward from the center of the spinner table 352 toward one side Wa of the sliced ​​wafer W. As a result, both the one side Wa and the other side Wb of the sliced ​​wafer W are cleaned.

[0062] After the spray of the cleaning water is stopped, the sliced ​​wafer W is dried by maintaining the high-speed rotation of the sliced ​​wafer W by the rotating part 354. After the drying is completed, the edge clamps 351 release the sliced ​​wafer W, and the sliced ​​wafer W is simply placed on the spinner table 352. The second transfer robot 22 holds the sliced ​​wafer W and stores it in the load port LP shown in FIG. 1. In this manner, both the one surface Wa and the other surface Wb of the sliced ​​wafer W are ground to remove deformation elements such as waviness and warpage, and a sliced ​​wafer W having a predetermined thickness is obtained.

[0063] In the peeling step, instead of the outer periphery cleaning device 6 provided in the peeling device 4, the outer periphery cleaning device 1 shown in FIG.

[0064] This outer periphery cleaning device 1 includes at least a holding table 30 that holds the wafer W on a holding surface 300a having a diameter smaller than the diameter of the sliced ​​wafer W, with the outer periphery portion Wd of the sliced ​​wafer W protruding from the holding surface 300a, a rotating unit 31 that rotates the holding table 30 about an axis at the center of the holding surface 300a, an upper roll sponge 43 that is rotatable about an upper rotation shaft 41 that is parallel to the holding surface direction (horizontal direction) of the holding table 30 and extends in a tangential direction to the outer periphery of the holding surface 300a and is positioned above the wafer W, a lower roll sponge 46 that is rotatable about a lower rotation shaft 45 that extends parallel to the upper rotation shaft 41 and is positioned below the wafer W, an upper cleaning nozzle 51 that supplies cleaning water to one side Wa of the wafer W, and a lower cleaning nozzle 53 that supplies cleaning water to the other side Wb of the wafer W.

[0065] The holding table 30 for holding the sliced ​​wafer W has, for example, a circular outer shape and includes an adsorption part 300 made of a porous material or the like for adsorbing the sliced ​​wafer W, and a frame body 301 for supporting the adsorption part 300. The adsorption part 300 communicates with a suction source (not shown), and adsorbs and holds the sliced ​​wafer W on a flat holding surface 300a consisting of an exposed surface of the adsorption part 300 and an upper surface of the frame body 301.

[0066] The rotating unit 31 includes at least a rotating shaft 310 whose axial direction is the Z-axis direction (vertical direction), and a motor 312 connected to the lower end side of the rotating shaft 310. The upper end side of the rotating shaft 310 is connected to the lower surface of the holding table 30 with the axis of the rotating shaft 310 aligned with the center of the holding surface 300a of the holding table 30. The rotating unit 31 may be a pulley mechanism or the like.

[0067] A table moving unit 12 is disposed below the holding table 30, and moves the sliced ​​wafer W held on the holding table 30 closer to or farther from the upper roll sponge 43 and the lower roll sponge 46. The table moving unit 12 is composed of a guide rail 121 extending in the X-axis direction, a slider 122 movable in the X-axis direction on the guide rail 121, and a ball screw mechanism (not shown) that is made up of a motor, a ball screw, etc. and generates a driving force to move the slider 122. The slider 122 supports the holding table 30 on its upper surface via the rotating unit 31. The slider 122 moves along the guide rail 121, and thereby the sliced ​​wafer W held on the holding table 30 and the upper roll sponge 43 and the lower roll sponge 46 can be moved closer to or farther from each other in the X-axis direction.

[0068] The peripheral cleaning device 1 includes a processing chamber 16 that contains at least the upper roll sponge 43 and the lower roll sponge 46. The processing chamber 16 has, for example, a substantially rectangular parallelepiped outer shape and is made up of a bottom plate 169 that is rectangular in plan view, four side walls that rise integrally in the +Z direction from the outer periphery of the bottom plate 169, and a top plate 165 that is connected to the upper ends of the four side walls. The processing chamber 16 also has a front wall 160a and a rear wall 160b that are two side walls that face each other in the X-axis direction, which is the moving direction of the sliced ​​wafers W.

[0069] An entrance 163 is formed in the front wall 160a on the -X direction side facing the holding table 30 of the processing chamber 16, through which the outer circumferential portion Wd of the sliced ​​wafer W held on the holding surface 300a of the holding table 30 enters the processing chamber 16. The entrance 163 is formed, for example, by cutting out the front wall 160a in a rectangular shape.

[0070] For example, air curtain forming parts (not shown) may be provided above and below the entrance 163 in the processing chamber 16. The air curtain formed by the air curtain forming part prevents water (cleaning water) adhering to one side Wa or the other side Wb of the sliced ​​wafers W from flowing out of the processing chamber 16 through the entrance 163.

[0071] 1, which rotatably supports the upper roll sponge 43 disposed in the processing chamber 16 and extends in the Y-axis direction which is parallel to the holding surface direction of the holding table 30 and tangent to the outer periphery of the holding surface 300a, is rotatably supported via a bearing (not shown). The upper rotating shaft 41 is disposed at a position obliquely above the outer periphery Wd of the sliced ​​wafers W that have entered the processing chamber 16, and is rotatable by a rotary drive source 424 such as a motor.

[0072] The upper roll sponge 43 is a sponge having a predetermined thickness molded into a cylindrical shape, and an insertion hole is formed at the center thereof, through which the upper rotating shaft 41 passes. The upper roll sponge 43 is, for example, an open-cell sponge having a structure in which air bubbles are interconnected, and a sponge made by foaming polyurethane (for example, Sofras sponge, manufactured by AION Co., Ltd.), a PVA sponge (for example, Belleater sponge, manufactured by AION Co., Ltd.), or a sponge molded by kneading a foaming agent or the like into rubber, or the like is used. The upper roll sponge 43 may be a closed-cell sponge. The outer surface of the upper roll sponge 43 serves as a cleaning surface for cleaning one surface Wa and the outer periphery Wd1 of the outer periphery portion Wd of the sliced ​​wafer W.

[0073] The lower rotation shaft 45 rotatably supports the lower roll sponge 46 disposed in the processing chamber 16 and extends parallel to the upper rotation shaft 41, and is rotatably supported via a bearing (not shown). The lower rotation shaft 45 is disposed at a position obliquely below the outer circumferential portion Wd of the sliced ​​wafer W in a state where the sliced ​​wafer W has entered the processing chamber 16, and is rotatable by a rotation drive source such as a motor. The lower roll sponge 46 is, for example, the same as the upper roll sponge 43, and the outer surface of the lower roll sponge 46 serves as a cleaning surface for cleaning the other surface Wb and the outer circumferential edge Wd1 of the outer circumferential portion Wd of the sliced ​​wafer W.

[0074] The upper roll sponge 43 and the lower roll sponge 46 are separated, for example by a small gap, in the axial direction of the upper rotating shaft 41, i.e., the Y-axis direction, which is also the axial direction of the lower rotating shaft 45, so that their outer surfaces do not come into contact with each other.

[0075] In the processing chamber 16, an upper cleaning nozzle 51 for supplying, for example, cleaning water to one side Wa of the sliced ​​wafer W, and a lower cleaning nozzle 53 for supplying, for example, cleaning water to the other side Wb of the sliced ​​wafer W are disposed. The upper cleaning nozzle 51 is disposed, for example, at a position obliquely above the outer peripheral portion Wd of the sliced ​​wafer W in a state where it has entered the processing chamber 16, and its jetting port is set so that the jetted cleaning water comes into contact with one side Wa of the outer peripheral portion Wd of the sliced ​​wafer W and then moves away from the outer peripheral edge Wd1 toward the outside of the sliced ​​wafer W. The lower cleaning nozzle 53 is disposed, for example, at a position obliquely below the outer peripheral portion Wd of the sliced ​​wafer W in a state where it has entered the processing chamber 16, and its jetting port is set so that the jetted cleaning water comes into contact with the other side Wb of the outer peripheral portion Wd of the sliced ​​wafer W and then moves away from the outer peripheral edge Wd1 toward the outside of the sliced ​​wafer W. The upper cleaning nozzle 51 and the lower cleaning nozzle 53 are disposed opposite to each other vertically.

[0076] In this embodiment, the upper cleaning nozzle 51 and the lower cleaning nozzle 53 are cleaning nozzles that spray two fluids obtained by mixing cleaning water and air, but are not limited thereto. For example, the upper cleaning nozzle 51 and the lower cleaning nozzle 53 are connected to a water source 59, which is made of a pump or the like and supplies, for example, pure water as cleaning water, via a water supply path 54, such as a flexible resin tube. An opening / closing valve (not shown) is disposed on the water supply path 54. The upper cleaning nozzle 51 and the lower cleaning nozzle 53 are also connected to an air source 58, which is made of a compressor or the like and supplies compressed air, via an air supply path 55, such as a flexible resin tube. An opening / closing valve (not shown) is disposed on the air supply path 55. The cleaning water supplied from the water source 59 and the air supplied from the air source 58 are mixed in the upper cleaning nozzle 51 or the lower cleaning nozzle 53, and are sprayed from each nozzle as two fluids onto one side Wa or the other side Wb of the sliced ​​wafer W for cleaning.

[0077] Alternatively, only cleaning water or only air may be sprayed from the upper cleaning nozzle 51 or the lower cleaning nozzle 53 onto one side Wa or the other side Wb of the sliced ​​wafer W to clean the one side Wa or the other side Wb of the sliced ​​wafer W with only cleaning water or only air. Alternatively, one side Wa or the other side Wb of the sliced ​​wafer W may be cleaned by alternately spraying cleaning water and air from the upper cleaning nozzle 51 or the lower cleaning nozzle 53.

[0078] The outer periphery cleaning device 1 includes, for example, an upper sponge cleaning nozzle 61 for spraying cleaning water onto the outer surface of the upper roll sponge 43 to clean the outer surface of the upper roll sponge 43, and a lower sponge cleaning nozzle 62 for spraying cleaning water onto the outer surface of the lower roll sponge 46 to clean the outer surface of the lower roll sponge 46, for example, in the treatment chamber 16. The upper sponge cleaning nozzle 61 and the lower sponge cleaning nozzle 62 are connected to the water source 59 by, for example, water flow paths 610 and water flow paths 630, respectively.

[0079] The upper sponge cleaning nozzle 61 is disposed above the upper roll sponge 43. That is, in this embodiment, the upper sponge cleaning nozzle 61 has an outlet opening toward the outer surface of the upper roll sponge 43 on the +X direction side that is not in contact with the sliced ​​wafer W, and the cleaning water ejected downward comes into contact with the outer surface on the +X direction side, and the cleaning water containing the remaining residue of the resin J adhering to the upper roll sponge 43 accumulates on the bottom plate 169 of the processing chamber 16 without coming into contact with one surface Wa of the outer peripheral portion Wd of the sliced ​​wafer W. For example, a drain port (not shown) is formed in the bottom plate 169, and the drain port is connected to a wastewater tank or the like via a drain hose or the like.

[0080] The lower sponge cleaning nozzle 62 is disposed, for example, at a position above the lower roll sponge 46. That is, in this embodiment, the lower sponge cleaning nozzle 62 has an outlet opening toward the outer surface of the lower roll sponge 46 on the +X direction side that does not contact the sliced ​​wafer W, and after the cleaning water sprayed downward comes into contact with, for example, the outer surface on the +X direction side, the cleaning water containing the remaining residue of the resin J adhering to the lower roll sponge 46 accumulates on the bottom plate 169 of the processing chamber 16 without coming into contact with one surface Wa of the outer peripheral portion Wd of the sliced ​​wafer W.

[0081] The upper sponge cleaning nozzle 61 and the lower sponge cleaning nozzle 62 may also be connected to the air source 58, and only air may be sprayed from the upper sponge cleaning nozzle 61 and the lower sponge cleaning nozzle 62 onto each roll sponge to blow off and clean the remaining residue of resin J adhering to the outer surface of each roll sponge. Alternatively, cleaning water and air may be sprayed alternately from the upper sponge cleaning nozzle 61 and the lower sponge cleaning nozzle 62 to clean the outer surface of each roll sponge.

[0082] The peripheral cleaning device 1 includes a gas-liquid separation unit 7 that separates the two fluids sprayed from the upper cleaning nozzle 51 or the lower cleaning nozzle 53 described above into water and air. The gas-liquid separation unit 7 has a flow path 73 with a zigzag cross section formed by combining, for example, two types of plates, a first plate 71 and a second plate 72, and includes an intake port 74 connected to the processing chamber 16 and an exhaust port 75 connected to a suction source 79 such as an ejector mechanism or a vacuum generator.

[0083] In this embodiment, for example, the first plate 71 and the second plate 72 are disposed in the housing 70 of the gas-liquid separation unit 7. As shown in FIG. 14, the first plate 71 has, for example, a rectangular outer shape in a plan view, and a rectangular through hole 710 is formed at one end side in the longitudinal direction of the first plate 71 in the thickness direction. On the other hand, the second plate 72 has, for example, a rectangular annular outer shape in a plan view, and a drain hole 722 is formed at one side of the second plate 72 in the longitudinal direction. A connector 723 is connected to the drain hole 722. As shown in FIG. 15, the connector 723 is connected to a drainage facility 724 through a drainage channel. At the four corners of the first plate 71 and the second plate 72, through holes 711 and 721 are formed, respectively, which penetrate in the thickness direction. The first plate 71 and the second plate 72 are set to have the same length and the same width, but are not limited thereto.

[0084] The first plate 71 and the second plate 72 are arranged in the housing 70 with their longitudinal directions aligned with the Z-axis direction (vertical direction), and the first plate 71 and the second plate 72 are arranged in a state in which they are alternately connected by passing bolts 760 through the through holes 711 and 721 and fastening nuts 761 to the bolts 760. That is, the second plate 72 faces the first plate 71 in the X-axis direction. The first plates 71 sandwiching the second plate 72 are arranged such that the through holes 710 are alternately opposite in the Z-axis direction, thereby forming a flow path 73 in which the cross section of the gas-liquid separation unit 7 cut in the X-axis direction is zigzag. Also, for example, each drain hole 722 of the second plate 72 is positioned below the second plate 72. For example, a housing drain hole 704 is formed on the bottom surface of the housing 70 to which a drain hose or the like is connected and which sends water that has flowed down from each drain hole 722 of the second plate 72 to a tank (not shown). Note that the zigzag flow path 73 may be, for example, a left-right zigzag in the Y-axis direction instead of an up-down zigzag in the Z-axis direction.

[0085] A two-fluid exhaust port 166 is formed in the rear wall 160b of the processing chamber 16, and one end of the intake port 74 of the gas-liquid separation unit 7 is connected to the two-fluid exhaust port 166 and the other end is connected to the through-hole 710 of the first plate 71. In addition, the exhaust port 75, the other end of which is connected to the suction source 79, has one end which is connected to the through-hole 710 of the first plate 71.

[0086] The two fluids sucked from the processing chamber 16 into the gas-liquid separation unit 7 collide with the side surface 71a of the first plate shown in Fig. 15 as they pass through the flow path 73, and the water constituting the two fluids turns into droplets and adheres to the side surface 71a. The water adhering to the side surface 71a of the first plate flows downward along the side surface 71a and is drained from the drainage hole 721 of the second plate 72. Therefore, the two fluids passing through the flow path 73 are separated into water and air in the gas-liquid separation unit 7, and mainly only the air is exhausted from the exhaust port 75, and the suction source 79 sucks in only the air.

[0087] The gas-liquid separation capacity can be adjusted by adjusting the number of first plates 71 and second plates 72 according to the amount of the two fluids used in the processing chamber 16. For example, when the amount of the two fluids is large, the number of first plates 71 and second plates 72 is increased to lengthen the flow path 73. On the other hand, when the amount of the two fluids is small, the number of first plates 71 and second plates 72 is decreased to shorten the flow path 73. By adjusting the length of the flow path 73 in this manner, it is not necessary to make the size of the gas-liquid separation unit 7 larger than necessary. [Explanation of symbols]

[0088] 1: Outer circumference cleaning device 2: Resin layer forming device 3: Grinding device 4: Peeling device 5: Delivery cassette section 6: Outer circumference cleaning device 7: Gas-liquid separation unit 12: Table moving section 16: Processing chamber 21: First transport robot 22: Second transport robot 23a: Cassette 25: Wafer transport unit 26a: First support stand 26b: Second support stand 27: Wafer detector 28: Sheet cutter 30: Holding table 31: Rotating part 32: Temporary unit 41: Upper rotating shaft 42: Holding portion 43: Upper roll sponge 45: Lower rotating shaft 46: Lower roll sponge 51: Upper cleaning nozzle 52: Cassette stage 53: Lower cleaning nozzle 54: Water supply path 55: Air supply path 58: Air source 59: Water source 61: Upper sponge cleaning nozzle 62: Lower sponge cleaning nozzle 63: Holding table 64: Movable block 65: Guide rail 66: Tilting section 67: Cleaning box 70: Housing 71: First plate 72: Second plate 73: Flow path 74: Intake port 75: Exhaust port 79: Suction source 100: Wafer manufacturing equipment 121: Guide rail 122: Slider 160a: Front wall 160b: Back wall 163: Entrance 165: Top plate 166: Two-fluid exhaust port 169: Bottom plate 200: Cabinet 211: Roll section 220: Stage 221: Sheet holding surface 230: Sheet placement section 232: Clamp section 240: Resin supply section 241: Resin supply nozzle 242: Dispenser 243: Supply port 250: Holding portion 251: Support structure 252: Holding table 260: Extension part 261: Ball screw 262: Motor 264: Lifting plate 270: Hardened part 300: Adsorption part 300a: Holding surface 301: Frame body 302: Chuck table 303: Grinding unit 305: Motor 306: Grinding feed unit 307: Ball screw 308: Guide rail 309: Lift plate 310: Rotating shaft 312: Motor 313a: First conveying unit 313b: Second conveying unit 320: Temporary placement table 321: Positioning mechanism 334: Grinding wheel 335: Spindle 336: Motor 337: Holder 340: Grinding wheel 350: Spin cleaning unit 351: Edge clamp 352: Spinner table 353: cleaning nozzle 354: rotating part 360: resin detection part 361: Camera 362: Camera 363: Image processing unit 364: Light emitting unit 365: Binarized image 366: Grinding marks 369, 370, 371: Back plate 412: Y-axis direction moving part 413: Z-axis direction moving part 420: Arm part 421: Holding pad 424: Rotation drive source 429: Movable plate 430: Overall peeling section 431: Gripping part 432: Moving member 441: Holding table 43: Outer part peeling part 454: Rotational drive source 479: Box 510: Delivery cassette 511: Shelf 512: First opening 513: Second opening 610: Water flow path 630: Water flow path 671: Wafer entrance 672: Sponge 673: Cleaning water nozzle 674: Drain 675: Gas-liquid separator 676: Exhaust port 704: Housing drain hole 710: Through hole 711: Through hole 721: Through hole 722: Drain hole 723: Connector 760: Bolt 761: Nut A: Loading / unloading area B: Processing area F: Seat LP: Load port P: Protective material R: Resin layer W: sliced ​​wafer Wa: one side Wb: other side

Claims

1. A method for manufacturing a wafer, comprising the steps of: grinding both surfaces of a sliced ​​wafer obtained by slicing an ingot; a resin layer forming step of forming a resin layer covering the entire surface of one surface of the sliced ​​wafer; a first holding step of holding the sliced ​​wafer on a chuck table via the resin layer; a first grinding step of grinding the other surface of the sliced ​​wafer with a grinding wheel; a resin layer peeling step of peeling off the resin layer from the one surface of the sliced ​​wafer after the first grinding step; a second grinding step of grinding the one surface of the sliced ​​wafer with a grinding wheel after the resin layer peeling step, and a resin remaining detection step of detecting the presence or absence of resin at the outer circumferential edge of the sliced ​​wafer after the resin layer peeling step and before the start of the second grinding step, The resin remaining detection step includes an imaging step of irradiating light onto the one surface of the sliced ​​wafer and imaging the one surface with a camera; a binarization step of binarizing the image acquired in the imaging step at a predetermined brightness; a determining step of determining that there is a resin residue when a white area in the binarized image obtained by the binarization step is equal to or larger than a predetermined range; A method for manufacturing a wafer comprising:

2. A grinding apparatus for use in the method for producing a wafer according to claim 1, a chuck table that holds the sliced ​​wafer on a holding surface; a grinding unit that grinds the sliced ​​wafer held on the chuck table with a grinding wheel; an imaging unit that projects light onto the outer circumferential edge of the sliced ​​wafer and images the outer circumferential edge; a resin detection unit that detects resin adhering to the sliced ​​wafer from the image captured by the imaging unit.

Images