Processing device

Abstract

To protect a sensor for detecting a tip of a processing tool easily.SOLUTION: When a sensor 50 is in a stand-by position 501, water is supplied from a first water supply port 63 and a second water supply port 64 of a water nozzle 60 to a light projection part 52 and a light reception part 53 to form water layers on surfaces of the light projection part 52 and the light reception part 53. Thus, the light projection part 52 and the light reception part 53 are protected. The water nozzle 60 is disposed in a processing chamber so as to correspond to the sensor 50 placed in the stand-by position. For the reason, the sensor 50 is placed in the stand-by position to allow water to be supplied properly from the water nozzle 60 to the light projection part 52 and the light reception part 53. For the reason, the structure can supply water to the light projection part 52 and the light reception part 53 satisfactorily and easily. Therefore, the light projection part 52 and the light reception part 53 can be easily protected.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a processing device. [Background technology]

[0002] As disclosed in Patent Document 1, a grinding device that grinds a wafer with a grinding wheel is provided with a sensor that detects the tip of the grinding wheel.

[0003] This sensor includes a light-emitting unit and a light-receiving unit, and as disclosed in Patent Document 2, a cover is provided to prevent grinding dust from adhering to the light-emitting unit and the light-receiving unit. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2017-127936 [Patent Document 2] Japanese Patent Application Publication No. 2016-112674 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conventional configuration, grinding chips may enter the inside of the cover and adhere to the light-emitting portion and the light-receiving portion.

[0006] Therefore, an object of the present invention is to easily prevent processing debris from adhering to a sensor that detects the tip of a processing tool (such as a cutting blade, grinding wheel, or bit), thereby protecting the sensor. [Means for solving the problem]

[0007] The processing apparatus of the present invention (the processing apparatus) is a processing apparatus comprising a chuck table that holds a workpiece, a processing unit that processes the workpiece held on the chuck table with a processing tool, a sensor that detects the tip of the processing tool, and a processing chamber that accommodates the chuck table, the processing tool, and the sensor. The sensor comprises a sensor body having a gap formed therein for the tip of the processing tool to enter, and a light-projecting unit that projects light and a light-receiving unit that receives the light, which are provided on the sensor body so as to face each other across the gap. The processing apparatus further comprises a horizontal movement mechanism that positions the sensor at a measurement position and a standby position by moving the sensor horizontally, and a water nozzle that is arranged in the processing chamber corresponding to the sensor positioned at the standby position and has at least two water supply ports that supply water to the light-projecting unit and the light-receiving unit.

[0008] The processing device may further include an air nozzle having an air outlet for injecting air into the light-emitting unit and the light-receiving unit, and a control unit that injects air from the air outlet when detecting the tip of the processing tool. [Effects of the Invention]

[0009] In this processing device, when the sensor is in the standby position, water is supplied to the light-emitting and light-receiving parts of the sensor from the water supply port of the water nozzle, forming a water layer on the surfaces of the light-emitting and light-receiving parts. This protects the light-emitting and light-receiving parts, and prevents processing debris generated during workpiece processing from adhering to the light-emitting and light-receiving parts.

[0010] In addition, in this processing device, the water nozzle is disposed in the processing chamber so as to correspond to the sensor positioned in the standby position. Therefore, by disposing the sensor in the standby position, the relative position of the water nozzle with respect to the light-emitting unit and the light-receiving unit can be appropriately set, enabling an appropriate supply of water to the light-emitting unit and the light-receiving unit. In this way, since the position of the water nozzle for supplying water to the light-emitting unit and the light-receiving unit can be easily adjusted, it is possible to efficiently and easily supply water to the light-emitting unit and the light-receiving unit. Therefore, the light-emitting unit and the light-receiving unit can be easily protected. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 2 is a perspective view showing the configuration of a grinding device. [Figure 2] FIG. [Figure 3] FIG. 1 is a side view showing the sensor in a measurement position. [Figure 4] FIG. 10 is a top view showing the sensor in a standby position. [Figure 5] FIG. 5(a) is a perspective view showing the water nozzle, and FIG. 5(b) is a top view showing the water nozzle. [Figure 6] FIG. 10 is a top view showing the movement of the sensor between the standby position and the measurement position. DETAILED DESCRIPTION OF THE INVENTION

[0012] As shown in Fig. 1, the grinding apparatus 1 according to this embodiment is an example of a processing apparatus and is an apparatus for grinding a wafer 100. The wafer 100 is an example of a workpiece, such as a semiconductor wafer. A front surface 101 of the wafer 100, which faces downward in Fig. 1, holds multiple devices and is protected by the attachment of a protective tape 103. A back surface 102 of the wafer 100 is the grinding surface on which the grinding process is performed.

[0013] The grinding device 1 includes a rectangular parallelepiped base 10 and a column 11 extending upward. An opening 13 is provided on the upper surface side of the base 10. In the opening 13, a chuck table 20 for holding the wafer 100 is disposed.

[0014] The chuck table 20 has a holding surface 22 made of a porous material on its upper surface. The holding surface 22 is connected to a suction source (not shown) to suction and hold the wafer 100. That is, the chuck table 20 holds the wafer 100 by means of the holding surface 22.

[0015] A drive mechanism 25 that rotates and drives the chuck table 20 is provided below the chuck table 20. This drive mechanism 25 allows the chuck table 20, with the wafer 100 held by the holding surface 22, to rotate about a rotation axis that passes through the center of the holding surface 22 and extends in the Z-axis direction.

[0016] Similarly, a Y-axis direction moving mechanism 26 is disposed below the chuck table 20. The Y-axis direction moving mechanism 26 moves the chuck table 20 in the Y-axis direction relative to the grinding mechanism 70. In this embodiment, the chuck table 20 is moved along the Y-axis direction by the Y-axis direction moving mechanism 26 between a holding position 301 on the −Y direction side where the wafer 100 is held by the holding surface 22, and a processing position 302 below the grinding mechanism 70.

[0017] A cover portion 27 that moves along the Y-axis direction together with the chuck table 20 is provided around the periphery of the chuck table 20. In addition, a bellows cover 12 that expands and contracts in the Y-axis direction is connected to the cover portion 27.

[0018] Furthermore, a column 11 is erected on the +Y direction side of the base 10. The column 11 is provided with a grinding mechanism 70 for grinding the wafer 100 and a grinding feed mechanism 30.

[0019] The grinding feed mechanism 30 is configured to move the grinding mechanism 70 in the Z-axis direction relative to the chuck table 20. The grinding feed mechanism 30 includes a pair of Z-axis guide rails 31 parallel to the Z-axis direction, a Z-axis moving table 33 that slides on the Z-axis guide rails 31, a Z-axis ball screw 32 parallel to the Z-axis guide rails 31, a Z-axis motor 34, and a holder 36 attached to the Z-axis moving table 33. The holder 36 supports the grinding mechanism 70.

[0020] The Z-axis moving table 33 is slidably installed on the Z-axis guide rail 31. A nut portion (not shown) is fixed to the Z-axis moving table 33. A Z-axis ball screw 32 is threadedly engaged with this nut portion. The Z-axis motor 34 is connected to one end of the Z-axis ball screw 32.

[0021] In the grinding feed mechanism 30, the Z-axis motor 34 rotates the Z-axis ball screw 32, causing the Z-axis moving table 33 to move in the Z-axis direction along the Z-axis guide rail 31. As a result, the holder 36 attached to the Z-axis moving table 33 and the grinding mechanism 70 supported by the holder 36 move in the Z-axis direction together with the Z-axis moving table 33.

[0022] The grinding mechanism 70 grinds the wafer 100 held by suction on the holding surface 22. The grinding mechanism 70 includes a spindle housing 71 fixed to the holder 36, a spindle 72 rotatably held in the spindle housing 71, a spindle motor 73 that rotates the spindle 72, a wheel mount 74 attached to the lower end of the spindle 72, and a grinding wheel 75 supported by the wheel mount 74.

[0023] The spindle housing 71 is held by the holder 36 so as to extend in the Z-axis direction. The spindle 72 extends in the Z-axis direction so as to be perpendicular to the holding surface 22 of the chuck table 20, and is rotatably supported by the spindle housing 71.

[0024] The spindle motor 73 is connected to the upper end side of the spindle 72. The spindle motor 73 rotates the spindle 72 about a rotation axis extending in the Z-axis direction.

[0025] The wheel mount 74 is formed in a disk shape and is fixed to the lower end of the spindle 72. The wheel mount 74 supports a grinding wheel 75.

[0026] The grinding wheel 75 is formed to have an outer diameter that is approximately the same as the outer diameter of the wheel mount 74. The grinding wheel 75 includes a wheel base 76 formed from a metal material. A plurality of grinding stones 77 arranged in a ring shape are fixed to the underside of the wheel base 76 around the entire circumference. The grinding stones 77 are an example of a processing tool, and are rotated together with the spindle 72 by the spindle motor 73, and grind the back surface 102 of the wafer 100 held on the chuck table 20 with the grinding surface at the tip.

[0027] In this way, the grinding mechanism 70 is a processing unit that processes the wafer 100 held on the chuck table 20 by the grinding wheel 77 as a processing tool.

[0028] The grinding device 1 also has a processing chamber 80 in the shape of a roughly rectangular parallelepiped box below the grinding mechanism 70 on the upper surface of the base 10.

[0029] The processing chamber 80 has a top plate 81 that forms the upper surface of the processing chamber 80, and has insertion holes 82 through which the spindle 72, wheel mount 74, and grinding wheel 75 of the grinding mechanism 70 are inserted. The grinding stone 77 of the grinding wheel 75 can be lowered along the Z-axis direction through this insertion hole 82 until it comes into contact with the back surface 102, which is the upper surface of the wafer 100 held on the holding surface 22 of the chuck table 20.

[0030] Furthermore, the processing chamber 80 is provided with a passage opening 84 for introducing the chuck table 20 into the processing chamber 80, on a front panel 83 that forms the surface on the -Y direction side of the processing chamber 80. The passage opening 84 is an opening that allows the chuck table 20 to move in the Y-axis direction. The chuck table 20 passes through this passage opening 84 and is moved between a holding position 301 outside the processing chamber 80 and a processing position 302 inside the processing chamber 80. Thus, the processing chamber 80 is configured to accommodate the chuck table 20 positioned at the processing position 302, the grinding wheel 77 of the grinding mechanism 70, and the sensor 50 of the tip detection mechanism 40 described below.

[0031] The grinding device 1 also has a tip end detection mechanism 40 below the grinding mechanism 70 for detecting the tip end of the grinding wheel 77. The tip end detection mechanism 40 has a sensor 50 for detecting the tip end of the grinding wheel 77, an arm 41 for supporting the sensor 50, a support column 42 for supporting the arm 41, and a swing motor 43.

[0032] The swing motor 43 is disposed within the base 10 below the processing chamber 80. The support pillar 42 extends upward from the swing motor 43 along the Z-axis direction, and its upper end is disposed within the processing chamber 80. The arm 41 is attached to the upper end of the swing motor 43 and extends horizontally within the processing chamber 80. The sensor 50 is attached to the tip of the arm 41 and is disposed within the processing chamber 80.

[0033] In the tip detection mechanism 40, the swing motor 43 rotates the support column 42 about a swing axis that passes through the support column 42 and extends in the Z-axis direction, thereby swinging the arm 41 and the sensor 50 disposed at the tip of the arm 41 in the horizontal direction. This allows the sensor 50 to be positioned at a standby position near the side wall 85 on the +X direction side of the processing chamber 80, and at a measurement position below the grinding wheel 77.

[0034] In this way, the arm 41, the support column 42, and the rotation motor 43 constitute a horizontal movement mechanism that moves the sensor 50 horizontally to position it at a measurement position or a standby position. The length of the support column 42 is adjusted so that the sensor 50 is higher than the holding surface 22 and lower than the top plate 81 so that the sensor 50 does not collide with the chuck table 20 and the top plate 81 of the processing chamber 80.

[0035] As shown in Figures 2 and 3, the sensor 50 has a sensor main body 51 in which a gap 510 is formed to allow the grinding wheel 77 (the tip of the grinding wheel 77) to enter, and a light-emitting section 52 that emits light and a light-receiving section 53 that receives light, which are provided on the sensor main body 51 so as to face each other across the gap 510.

[0036] The sensor main body 51 has a roughly U-shaped configuration and includes a first pillar section 511 and a second pillar section 512 that both extend in the Z-axis direction, and a bottom plate section 513 that is provided to connect the bottoms of the second pillar section 512 and the second pillar section 512. A light-emitting section 52 is provided on the inner surface (on the second pillar section 512 side) of the tip of the first pillar section 511. A light-receiving section 53 is provided on the inner surface (on the first pillar section 511 side) of the tip of the second pillar section 512.

[0037] Light-projecting unit 52 and light-receiving unit 53 are disposed opposite each other across gap 510 so that their optical axes coincide. Light-projecting unit 52 is configured to irradiate light L transmitted from light source 522 via light-projecting optical fiber 521 (see FIG. 3) disposed inside first pillar portion 511 toward light-receiving unit 53. Meanwhile, light-receiving unit 53 is configured to receive light L irradiated from light-projecting unit 52 and transmit the received light via light-receiving optical fiber 531 to, for example, a light amount meter 532 that measures the amount of light received by light-receiving unit 53.

[0038] The optical axes of light-projecting unit 52 and light-receiving unit 53 are set to be aligned in the radial direction of grinding wheel 75 including grinding wheel 77 when sensor 50 is placed at the measurement position below grinding wheel 77. Gap 510 between light-projecting unit 52 and light-receiving unit 53 is formed to have a size that allows the tip of grinding wheel 77 to enter.

[0039] Therefore, when the sensor 50 is placed at the measurement position, as shown in Figure 3, the tip of the grinding wheel 77 can enter the gap 510 in the radial direction of the grinding wheel 75 so as to block the optical axes of the light-emitting unit 52 and the light-receiving unit 53.

[0040] As shown in FIGS. 2 and 3, the sensor 50 also has an air nozzle 55 that is provided to fit into the gap 510.

[0041] The air nozzle 55 comprises an L-shaped first member 551 that contacts the inner surface of the first pillar portion 511 of the sensor 50, an L-shaped second member 552 that contacts the inner surface of the second pillar portion 512 of the sensor 50, and a bottom plate portion 553 that is arranged to connect the bottoms of the first member 551 and the second member 552.

[0042] A first air outlet 56 for injecting air toward the light-projecting unit 52 of the sensor 50 is provided at the upper end of the first member 551. A second air outlet 57 for injecting air toward the light-receiving unit 53 of the sensor 50 is provided at the upper end of the second member 552. The first air outlet 56 and the second air outlet 57 are connected to the air source 401. The first air outlet 56 and the second air outlet 57 are configured to be connected to the air source 401, thereby injecting air toward the light-projecting unit 52 and the light-receiving unit 53, respectively. Thus, the air nozzle 55 has the first air outlet 56 and the second air outlet 57 for injecting air onto the light projecting part 52 and the light receiving part 53 .

[0043] 2 and 4, the air nozzle 55 is disposed on the sensor 50 so as to extend beyond the sensor 50 in the standby position toward the side wall 85 of the processing chamber 80. The inner corners of the first member 551 and the second member 552 of the air nozzle 55 on the +X direction side (side wall 85 side) are cut out obliquely, and the surfaces formed at the cut-out corners serve as sensor-side positioning surfaces 58. The sensor-side positioning surfaces 58 are used to connect (position) the water nozzle 60 and the air nozzle 55 to each other.

[0044] The water nozzle 60 is disposed on the inner wall of the side wall 85 (inside the processing chamber 80) so as to correspond to the sensor 50 positioned at the standby position. In this embodiment, the water nozzle 60 is provided on the inner wall of the side wall 85 of the processing chamber 80 at a position that allows it to be connected to the sensor 50 in the standby position.

[0045] 5(a) and 5(b), water nozzle 60 has a plate-shaped water nozzle body 61 and a protrusion 62 formed integrally with water nozzle body 61. Protrusion 62 has a generally rectangular shape with two corners on the -X direction side cut out, and a first water supply port 63 and a second water supply port 64 are formed at the two cut-out corners, respectively.

[0046] The first water supply inlet 63 and the second water supply inlet 64 are each positioned within the gap 510 of the sensor 50 when the sensor 50 is positioned in the standby position and the sensor 50 and the water nozzle 60 are connected to each other, for supplying (spraying) water to the light-emitting unit 52 and the light-receiving unit 53.

[0047] That is, first water supply inlet 63 and second water supply inlet 64 are connected to an external water source 402 via a water supply passage 65 and a water supply inlet 66 provided in water nozzle body 61. First water supply inlet 63 and second water supply inlet 64 are connected to water source 402, and are configured to supply water to light-emitting unit 52 and light-receiving unit 53 of sensor 50 in the standby position.

[0048] The water nozzle 60 also has a positioning portion 67 below the water nozzle body 61. The positioning portion 67 has a substantially rectangular plate portion with two corners on the -X direction side cut out at an angle, and the surfaces formed at the two cut-out corners serve as water-nozzle-side positioning surfaces 68 for connecting (positioning) the water nozzle 60 and the air nozzle 55 to each other. When the sensor 50 moves toward the standby position, these water-nozzle-side positioning surfaces 68 abut against the sensor-side positioning surfaces 58 provided on the air nozzle 55 of the sensor 50, thereby positioning the water nozzle 60 and the sensor 50 relative to each other; in other words, they connect the sensor 50 and the water nozzle 60 in the standby position to each other so that the water nozzle 60 can appropriately supply water to the light-projecting unit 52 and the light-receiving unit 53.

[0049] 1, the grinding apparatus 1 includes a control unit 7 that controls each component of the grinding apparatus 1. The control unit 7 includes a CPU that performs calculations according to a program, a storage medium such as a memory, etc. The control unit 7 controls each component of the grinding apparatus 1, including the air nozzle 55 and the water nozzle 60, to perform grinding on the wafer 100.

[0050] Furthermore, during or before the grinding process, the control unit 7 detects the tip of the grinding wheel 77 using the sensor 50. This detection is performed, for example, to check the condition of the tip of the grinding wheel 77.

[0051] In the operation of detecting the leading end of the grinding wheel 77, the control unit 7 first irradiates light L from the light source 522 from the light projecting unit 52 toward the light receiving unit 53 of the sensor 50 (see FIG. 3). Note that the light projecting unit 52 may be configured to always irradiate light L toward the light receiving unit 53.

[0052] Next, as shown in FIG. 6, the control unit 7 drives the rotation motor 43 of the tip detection mechanism 40 to rotate the arm 41 and the sensor 50 as indicated by the arrow 601, thereby positioning the sensor 50 from the standby position 501 to the measurement position 502.

[0053] 3, the gap 510 of the sensor 50 is positioned below the grinding wheel 77. The control unit 7 controls the grinding feed mechanism 30 (see FIG. 1) to lower the grinding mechanism 70, thereby lowering the grinding wheel 77 toward the gap 510 of the sensor 50.

[0054] As the grinding wheel 77 descends, the tip of the grinding wheel 77 enters the gap 510 and becomes positioned between the light-projecting unit 52 and the light-receiving unit 53. This makes it difficult for the light L from the light-projecting unit 52 to be received by the light-receiving unit 53, and the amount measured by the light quantity meter 532 decreases. Based on the measurement result of the light quantity meter 532, the control unit 7 detects that the amount of light received by the light-receiving unit 53 has fallen below a preset amount (for example, the light-receiving unit 53 has stopped receiving light L), thereby determining that the tip of the grinding wheel 77 has been detected and stopping the descent of the grinding mechanism 70. The control unit 7 can then confirm the length (amount of wear) of the grinding wheel 77 by, for example, measuring the height of the grinding mechanism 70 when the amount of light received by the light-receiving unit 53 has decreased. In addition, the difference between the height of the holding surface 22 of the chuck table 20 and the height of the light receiving unit 53 is set in advance, and after the control unit 7 determines that the tip of the grinding wheel 77 has been detected, it performs a setup to store the height of the grinding mechanism 70 when the tip of the grinding wheel 77 contacts the holding surface 22.

[0055] Furthermore, when detecting the tip of the grinding wheel 77, the control unit 7 connects the first air outlet 56 and the second air outlet 57 of the air nozzle 55 to the air source 401, thereby causing air to be ejected from the first air outlet 56 and the second air outlet 57 toward the light-projecting unit 52 and the light-receiving unit 53. For example, when detecting the tip of the grinding wheel 77, the control unit 7 continues to eject air toward the light-projecting unit 52 and the light-receiving unit 53. This prevents grinding debris and machining debris from adhering to the light-projecting unit 52 and the light-receiving unit 53.

[0056] For example, the control unit 7 may continue to jet air from the first air jet port 56 and the second air jet port 57 from the time the sensor 50 starts to pivot from the standby position toward the measurement position until the sensor 50 returns to the standby position. Alternatively, the control unit 7 may continue to jet air from the first air jet port 56 and the second air jet port 57 from the time the sensor 50 is placed in the standby position until the tip of the grinding wheel 77 is detected.

[0057] After the tip end detection of the grinding wheel 77 is completed, the control unit 7 drives the rotation motor 43 of the tip end detection mechanism 40 to rotate the arm 41 and the sensor 50 as shown by the arrow 602, thereby positioning the sensor 50 from the measurement position 502 to the standby position 501, as shown in FIG. 6 .

[0058] At this time, the water nozzle side positioning surface 68 of the water nozzle 60 abuts against the sensor side positioning surface 58 provided on the air nozzle 55 of the sensor 50 that has moved toward the standby position, and the water nozzle 60 and the sensor 50 are positioned and connected to each other.

[0059] After sensor 50 has been placed in the standby position in this manner, control unit 7 connects first water supply inlet 63 and second water supply inlet 64 of water nozzle 60 to water source 402 (see FIG. 5(a)). As a result, water is supplied from first water supply inlet 63 and second water supply inlet 64 to light-projecting unit 52 and light-receiving unit 53 of sensor 50, which is in the standby position, and a water layer (water film) is formed on the surfaces of light-projecting unit 52 and light-receiving unit 53. As a result, light-projecting unit 52 and light-receiving unit 53 are protected by the water layer. Thereafter, the control unit 7 performs grinding processing on the wafer 100 using the grinding mechanism 70, for example.

[0060] As described above, in this embodiment, when sensor 50 is in standby position 501, water is supplied to light-projecting unit 52 and light-receiving unit 53 from first water supply port 63 and second water supply port 64 of water nozzle 60, and a water layer is formed on the surfaces of light-projecting unit 52 and light-receiving unit 53. This protects light-projecting unit 52 and light-receiving unit 53, making it possible to prevent grinding debris generated during processing of wafer 100 from adhering to light-projecting unit 52 and light-receiving unit 53.

[0061] Furthermore, in this embodiment, the water nozzle 60 is disposed in the processing chamber 80 so as to correspond to the sensor 50 positioned at the standby position. Therefore, by disposing the sensor 50 at the standby position, the relative position of the water nozzle 60 with respect to the light-projecting unit 52 and the light-receiving unit 53 can be appropriately set, enabling an appropriate supply of water to the light-projecting unit 52 and the light-receiving unit 53. In this way, the position of the water nozzle 60 for supplying water to the light-projecting unit 52 and the light-receiving unit 53 can be easily adjusted, making it possible to properly and easily supply water to the light-projecting unit 52 and the light-receiving unit 53. Therefore, the light-projecting unit 52 and the light-receiving unit 53 can be easily protected.

[0062] Furthermore, in this embodiment, the sensor 50 (air nozzle 55) has a sensor-side positioning surface 58, and the water nozzle 60 has a water-nozzle-side positioning surface 68. When the sensor 50 moves toward the standby position, the water-nozzle-side positioning surface 68 abuts against the sensor-side positioning surface 58 of the sensor 50, thereby positioning the water nozzle 60 and the sensor 50 relative to each other; that is, the sensor 50 and the water nozzle 60 in the standby position can be connected to each other so that the water nozzle 60 can appropriately supply water to the light-projecting unit 52 and the light-receiving unit 53. This makes it easier and more efficient to adjust the position of the water nozzle 60 for supplying water to the light-projecting unit 52 and the light-receiving unit 53.

[0063] Furthermore, in this embodiment, when detecting the tip of the grinding wheel 77, air is sprayed from the first air outlet 56 and the second air outlet 57 of the air nozzle 55 to the light projecting unit 52 and the light receiving unit 53 of the sensor 50. This makes it possible to prevent water droplets, machining chips floating in the machining chamber 80, and grinding water spray from adhering to the light projecting unit 52 and the light receiving unit 53. This makes it possible to prevent errors from occurring in detecting the tip of the grinding wheel 77.

[0064] In addition, when the sensor 50 is in the standby position, the control unit 7 may continuously supply water from the water nozzle 60 to the light-emitting unit 52 and the light-receiving unit 53, or may be configured to supply water intermittently at predetermined time intervals or temporarily for a predetermined period of time.

[0065] In this embodiment, the water nozzle 60 has two water supply ports, a first water supply port 63 and a second water supply port 64, for supplying water to the light-projecting unit 52 and the light-receiving unit 53. In this regard, the water nozzle 60 may have three or more water supply ports for supplying water to the light-projecting unit 52 and the light-receiving unit 53. That is, the water nozzle 60 is disposed in the processing chamber 80 so as to correspond to the sensor 50 positioned in the standby position, and has at least two water supply ports for supplying water to the light-projecting unit 52 and the light-receiving unit 53.

[0066] Furthermore, in the above-described configuration, when detecting the leading end of the grinding wheel 77, the control unit 7 continues to blow air toward the light-projecting unit 52 and the light-receiving unit 53. In this regard, the control unit 7 may be configured to blow air toward the light-projecting unit 52 and the light-receiving unit 53 intermittently at predetermined time intervals or temporarily for a predetermined period of time when detecting the leading end of the grinding wheel 77.

[0067] In addition, in this embodiment, a grinding device 1 is illustrated as an example of a processing device. In this regard, the processing device of this embodiment may be any device that has a sensor that detects the tip of a processing tool (such as a cutting blade, a grinding wheel, or a cutting tool), and may be, for example, other processing devices such as a polishing device that polishes a workpiece or a cutting device that divides a workpiece into chips. [Explanation of symbols]

[0068] 1: grinding device, 7: control unit, 10: base, 11: column, 12: bellows cover, 13: opening, 20: chuck table, 22: holding surface, 25: drive mechanism, 26: Y-axis direction movement mechanism, 27: cover part, 30: grinding feed mechanism, 31: Z-axis guide rail, 32: Z-axis ball screw, 33: Z-axis moving table, 34: Z-axis motor, 36: holder, 40: tip detection mechanism, 41: arm, 42: support column, 43: Swing motor, 50: Sensor, 51: Sensor body, 52: Light emitting unit, 53: Light receiving unit, 55: air nozzle, 56: first air outlet, 57: second air outlet, 58: Sensor side positioning surface, 60: Water nozzle, 61: Water nozzle body, 62: Protrusion, 63: 1st water supply port, 64: 2nd water supply port, 65: Water supply channel, 66: Water supply port, 67: Positioning portion, 68: Water nozzle side positioning surface, 70: Grinding mechanism, 71: spindle housing, 72: spindle, 73: spindle motor, 74: Wheel mount, 75: Grinding wheel, 76: Wheel base, 77: Grinding stone, 80: processing chamber, 81: top plate, 82: insertion hole, 83: front plate, 84: passage opening, 85: side wall, 100: wafer, 101: front surface, 102: back surface, 103: protective tape, 301: Holding position, 302: Processing position, 401: Air source, 402: Water source, 501: standby position, 502: measurement position, 510: gap, 511: first pillar portion, 512: second pillar portion, 513: bottom plate portion, 521: light projection optical fiber, 522: light source, 531: Light receiving optical fiber, 532: Light amount measuring device, 551: First member, 552: second member, 553: bottom plate portion, 601: arrow, 602: arrow, L: light

Claims

1. A processing device comprising: a chuck table for holding a workpiece; a processing unit for processing the workpiece held on the chuck table with a processing tool; a sensor for detecting a tip of the processing tool; and a processing chamber for accommodating the chuck table, the processing tool, and the sensor, The sensor includes a sensor body having a gap formed therein for allowing the tip of the processing tool to enter, and a light-projecting unit that projects light and a light-receiving unit that receives the light, the light-projecting unit and the light-receiving unit being provided on the sensor body so as to face each other across the gap, a horizontal movement mechanism that moves the sensor horizontally to position it at a measurement position and a standby position; a water nozzle disposed in the processing chamber corresponding to the sensor positioned at the standby position, the water nozzle having at least two water supply ports for supplying water to the light projecting unit and the light receiving unit; Processing equipment.

2. an air nozzle having an air injection port for injecting air onto the light projecting portion and the light receiving portion; and a control unit that injects air from the air injection port when detecting the tip of the processing tool. The processing device according to claim 1.

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