Processing equipment

Abstract

To prevent a binary fluid from scattering on a holding surface in a processing device having a function for jetting the binary fluid from a nozzle to clean the holding surface of a porous member.SOLUTION: A processing device includes: a chuck table which suctions and holds a workpiece on a holding surface 500 having irregularities of a porous member 50; and a processing unit which processes the workpiece held by the holding surface 500. The processing device includes a cleaning unit 7 having a nozzle 77 which jets a binary fluid 778, in which water and air are mixed, in a jetting direction inclining relative to the holding surface 500. The cleaning unit 7 includes a scattering prevention part 786 which prevents the binary fluid 778 from being scattered by the irregularities of the holding surface 500.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a processing apparatus having a function of spraying a two-fluid onto a holding surface of a porous member for cleaning.

Background Art

[0002] In a grinding apparatus that sucks and holds a wafer on a chuck table having an upper surface of a suction portion made of a porous member as a holding surface, a nozzle for injecting a two-fluid is provided, and the holding surface is cleaned by the two-fluid injected from the nozzle (see, for example, Patent Document 1 and Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] The holding surface of the porous member has irregularities. Therefore, the two-fluid injected from the nozzle scatters on the holding surface due to the irregularities. That is, the two-fluid hitting the holding surface not only flows in the direction following the holding surface, which is the forward direction with respect to the injection direction, but also scatters to the reverse direction side with respect to the injection direction. And, due to the two-fluid scattered on the holding surface in this way, the processing chips may reattach to the holding surface.

[0005] Therefore, in a processing apparatus having a function of spraying a two-fluid from a nozzle to clean the holding surface of a porous member, there is a problem of preventing the two-fluid from scattering on the holding surface.

Means for Solving the Problems

[0006] The present invention relates to a processing apparatus comprising a chuck table for suction-holding a workpiece on a holding surface having irregularities of a porous member, and a processing unit for grinding or polishing the workpiece held by the holding surface, wherein the apparatus includes a cleaning unit having a nozzle for spraying a two-fluid mixture of water and air in a spraying direction inclined with respect to the holding surface, the cleaning unit includes a scattering prevention unit for preventing the two-fluid mixture sprayed from the nozzle from scattering at least to the side and rear in the spraying direction due to the irregularities of the holding surface, the scattering prevention unit includes a front plate having a lower surface facing the holding surface and positioned on the front side in the spraying direction of the two-fluid mixture The front plate is designed to guide the two fluids forward and cause them to descend upon contact with the front plate, thereby preventing diffuse reflection of the two fluids. The device comprises a rear plate positioned on the opposite side of the front plate, sandwiching the nozzle; a pair of side plates connected to both sides of the rear plate, surrounding the nozzle together with the rear plate; and flat plates connected to the lower ends of each of the side plates, extending in a direction parallel to the holding surface and moving away from each other. The scattering prevention unit further includes a parallel plate provided at the lower end of the rear plate, parallel to the reduced diameter portion at the lower end of the nozzle, such that a gap is formed between the parallel plate and the reduced diameter portion. The gap between the tip of the parallel plate and the tip of the reduced diameter portion of the nozzle becomes a negative pressure when the two fluids are ejected from the injection portion provided at the lower end of the reduced diameter portion, functioning as an outside air introduction portion that introduces outside air from the rear side of the rear plate. The parallel plate also functions as a guide that ejects the introduced outside air toward the injection portion side of the nozzle, and it is desirable that the introduced outside air prevents the scattering of the two fluids backward in the injection direction due to the unevenness of the holding surface. [Effects of the Invention]

[0007] In this invention, the cleaning unit is equipped with a scattering prevention unit that prevents the scattering of the two fluids due to irregularities on the holding surface of the chuck table, thereby reducing the risk of processing debris re-adhering to the holding surface. Furthermore, by providing an outside air intake section that guides outside air in the direction of injection using the two fluids ejected by the nozzle, the risk of scattering of the two fluids can be further reduced. [Brief explanation of the drawing]

[0008] [Figure 1]This is a perspective view showing an example of a processing apparatus. [Figure 2] This is a front view showing an example of a washing unit and a chuck table. [Figure 3] This is a cross-sectional view showing the state in which two fluids are being injected from the nozzle toward the holding surface of the chuck table. [Figure 4] This is a perspective view showing an example of a gas-liquid separation unit. [Figure 5] This is a perspective view showing the state in which two fluids are being injected from a rotating nozzle toward the holding surface of the chuck table. [Modes for carrying out the invention]

[0009] 1. Configuration of the processing equipment The processing apparatus 1 shown in Figure 1 is a processing apparatus that processes a workpiece 100 held on a chuck table 5 using processing units consisting of a rough grinding unit 30, a finish grinding unit 31, and a polishing unit 32. The processing apparatus 1 is equipped with a control unit 17 that controls various mechanisms when transporting the workpiece 100, grinding, polishing, etc.

[0010] The processing apparatus 1 is configured with a second apparatus base 11 connected to the rear (+Y direction side) of a first apparatus base 10. The first apparatus base 10 is an loading / unloading area 91 where the workpiece 100 is loaded and unloaded. The second apparatus base 11 is a processing area 92 where the workpiece 100, held on the chuck table 5 by a rough grinding unit 30, a finish grinding unit 31, or a polishing unit 32, is processed.

[0011] The front side (-Y direction side) of the first device base 10 is provided with a first cassette mounting section 150 and a second cassette mounting section 151. The first cassette mounting section 150 is fitted with a first cassette 173 containing the workpiece 100 before processing, and the second cassette mounting section 151 is fitted with a second cassette 174 containing the workpiece 100 after processing.

[0012] An opening (not shown) is provided at the rear (+Y direction side) of the first cassette 173, and a robot 155 is positioned behind this opening to unload the workpiece 100 before processing from the first cassette 173 and load the processed workpiece 100 into the second cassette 174. A temporary storage area 152 is provided adjacent to the robot 155, and the temporary storage area 152 is equipped with a rotatable table 153 and a camera 154 that images the upper surface 101 of the workpiece 100 placed on the table 153.

[0013] A first transport mechanism 171 is positioned adjacent to the temporary storage area 152, which rotates while holding the workpiece 100. The first transport mechanism 171 can hold the workpiece 100 located in the temporary storage area 152 and transport it to any of the chuck tables 5 located within the processing area 92. Next to the first transport mechanism 171, a second transport mechanism 172 is provided, which rotates while holding the processed workpiece 100. Near the second transport mechanism 172, a spinner cleaning unit 156 is positioned to clean the processed workpiece 100 transported by the second transport mechanism 172. The workpiece 100 cleaned by the spinner cleaning unit 156 is then loaded into a second cassette 174 by a robot 155.

[0014] A first column 12 is erected on the front -X side of the second device base 11, and a rough grinding feed unit 20 is arranged on the side of the first column 12. The rough grinding feed unit 20 includes a ball screw 200 having an axis in the vertical direction (Z-axis direction), a pair of guide rails 201 arranged parallel to the ball screw 200, a motor 202 connected to the ball screw 200 to rotate the ball screw 200, a lifting plate 203 whose internal nut is screwed onto the ball screw 200 and whose side slides against the guide rail 201, and a holder 204 connected to the lifting plate 203 to hold the rough grinding unit 30. When the motor 202 rotates the ball screw 200, the lifting plate 203 is guided by the guide rail 201 and moves back and forth in the Z-axis direction, and the rough grinding unit 30, which is supported by a holder 204 connected to the lifting plate 203, also moves back and forth in the Z-axis direction.

[0015] The rough grinding unit 30 comprises a rotating shaft 300 whose axial direction is vertical (Z-axis direction), a housing 301 that rotatably supports the rotating shaft 300, a motor 302 that rotationally drives the rotating shaft 300, a mount 303 connected to the lower end of the rotating shaft 300, and a grinding wheel 304 that is detachably connected to the lower surface of the mount 303. The grinding wheel 304 comprises a wheel base 305 and a plurality of roughly rectangular parallelepiped rough grinding wheels 306 arranged in an annular shape on the bottom surface of the wheel base 305.

[0016] Furthermore, a second column 13 is erected on the rear -X side of the second device base 11, and a finish grinding feed unit 21 is positioned in front of the second column 13. The finish grinding feed unit 21 is configured similarly to the rough grinding feed unit 20 and can feed the finish grinding unit 31 in the Z-axis direction. The finish grinding unit 31 is equipped with a finish grinding wheel 307 in which the abrasive grains contained are smaller than those of the rough grinding wheel 306, and the other configurations are the same as those of the rough grinding unit 30. The parts constituting the finish grinding feed unit 21 are given the same reference numerals as those of the rough grinding feed unit 20, and their descriptions are omitted. Also, for the finish grinding unit 31, the parts other than the finish grinding wheel 307 are given the same reference numerals as those of the rough grinding unit 30, and their descriptions are omitted.

[0017] On the rear +X side above the second device base 11, a third column 14 is erected side by side with the above-mentioned second column 13 in the X-axis direction. On the front surface of the third column 14, an X-axis direction moving unit 24 is arranged. The X-axis direction moving unit 24 includes a ball screw 240 having an axis in the X-axis direction, a pair of guide rails 241 arranged in parallel with the ball screw 240, a motor 242 for rotating the ball screw 240, and a movable plate 243 whose internal nut is screwed onto the ball screw 240 and whose side portion is in sliding contact with the guide rail 241. When the motor 242 rotates the ball screw 240, the movable plate 243 is guided by the guide rail 241 and moves in the X-axis direction accordingly, and the polishing unit 32 arranged on the movable plate 243 moves in the X-axis direction along with the movement of the movable plate 243.

[0018] On the front surface of the movable plate 243, a polishing feed unit 25 for raising and lowering the polishing unit 32 in the Z-axis direction to approach or separate from the chuck table 5 is arranged. The polishing feed unit 25 includes a ball screw 250 having an axis in the vertical direction, a pair of guide rails 251 arranged in parallel with the ball screw 250, a motor 252 connected to the ball screw 250 for rotating the ball screw 250, a lifting plate 253 whose internal nut is screwed onto the ball screw 250 and whose side portion is in sliding contact with the guide rail 251, and a holder 254 connected to the lifting plate 253 for holding the polishing unit 32. When the motor 252 rotates the ball screw 250, the lifting plate 253 is guided by the guide rail 251 and moves in the Z-axis direction, and the polishing unit 32 supported by the holder 254 also moves in the Z-axis direction.

[0019] The polishing unit 32 includes a spindle 320 whose axial direction is the Z-axis direction, a housing 321 that rotatably supports the spindle 320, a motor 322 that rotationally drives the spindle 320, a mount 323 fixed to the lower end of the spindle 320, and a circular polishing pad 324 detachably attached to the lower surface of the mount 323. The polishing pad 324 is made of, for example, a non-woven fabric such as felt, and a through-hole (not shown) through which slurry (a polishing liquid containing free abrasive grains) passes is formed in the central portion. The diameter of the polishing pad 324 is larger than the diameter of the chuck table 5.

[0020] As shown in FIG. 1, a turntable 6 is disposed on the second device base 11, and, for example, four chuck tables 5 are arranged on the upper surface of the turntable 6 at equal intervals in the circumferential direction. At the center of the turntable 6, a rotating shaft (not shown) for rotating the turntable 6 is disposed, and the turntable 6 can be rotated about an axis in the Z-axis direction with the rotating shaft as the center. By rotating the turntable 6, the four chuck tables 5 can be revolved, and the chuck tables 5 can be sequentially positioned below the rough grinding unit 30, below the finish grinding unit 31, and below the polishing unit 32.

[0021] The spaces between adjacent chuck tables 5 are partitioned by partition plates 161. The individual regions partitioned by the partition plates 161 are a loading / unloading area 181 where the workpiece 100 is loaded and unloaded, a rough grinding area 182 where rough grinding is performed, a finish grinding area 183 where finish grinding is performed, and a polishing area 184 where polishing is performed.

[0022] The spinner cleaning unit 156 includes a spinner table 157 that holds and rotates the workpiece, and a nozzle 158 that injects a cleaning liquid onto the workpiece. Instead of the cleaning liquid, a two-fluid mixture of water and air may be used.

[0023] A cleaning unit 7, as shown in Figure 2, is installed in the loading / unloading area 181. As shown in Figure 2, the cleaning unit 7 includes a nozzle unit 72 for spraying two fluids, an arm 73 to which the nozzle unit 72 is fixed at the tip, a swivel motor 71 for rotating the arm 73, and a lifting actuator 74 for raising and lowering the swivel motor 71, the arm 73, and the nozzle unit 72. An air source 75 and a water source 76 are connected to the nozzle unit 72, and a two-fluid mixture of air supplied from the air source 75 and water supplied from the water source 76 can be sprayed from the nozzle unit 72.

[0024] The chuck table 5 comprises a porous member 50 for suction and holding a workpiece, a frame 51 that supports the porous member 50 from below and the side, and a support base 52 that supports the frame 51. The upper surface of the porous member 50 is a holding surface 500 for suction and holding a workpiece, and the holding surface 500 has irregularities. A shaft portion 53 is connected to the support base 52. A flow path 54 through which water or air flows is formed inside the frame 51, the support base 52, and the shaft portion 53. One end of the flow path 54 is open at multiple locations on the upper surface of the frame 51. The other end of the flow path 54 can be selectively connected to a suction source 557, an air source 558, and a water source 559 via three flow rate adjustment valves 551, 552, and 553 and three on / off valves 554, 555, and 556. When valve 554 is open and valves 555 and 556 are closed, the porous member 50 and the suction source 557 are in communication, allowing a suction force to be applied to the holding surface 500. When valve 555 is open and valves 554 and 556 are closed, the porous member 50 and the air source 558 are in communication, allowing air to be ejected from the holding surface 500. When valve 556 is open and valves 554 and 555 are closed, the porous member 50 and the water source 559 are in communication, allowing water to be ejected from the holding surface 500. Furthermore, when valves 555 and 556 are open and valve 554 is closed, the porous member 50 and the air source 558 and water source 559 are in communication, allowing a mixture of air and water to be ejected from the holding surface 500.

[0025] A bracket 61 is fixed to the underside of the turntable 6, and the bracket 61 holds a motor 56 that rotates the chuck table 5. A drive pulley 562 is disposed at the upper end of the shaft 561 of the motor 56. On the other hand, a driven pulley 563 is disposed on the shaft portion 53 of the chuck table 5. A belt 564 is wound around the drive pulley 562 and the driven pulley 563. When the motor 56 rotates the shaft 561, the rotational force is transmitted to the shaft portion 53 by the belt 564, causing the chuck table 5 to rotate. The support base 52 is rotatably supported by a bearing 62 fixed to the turntable 6.

[0026] As shown in Figure 3, the nozzle unit 72 is equipped with a nozzle 77 that injects two fluids onto the holding surface 500. The nozzle 77 comprises a cylindrical body 771, an air inlet 772 formed on the side of the cylindrical body 771 and communicating with an air source 75, a water inlet 773 formed on the side of the cylindrical body 771 and communicating with a water source 76, a reduced-diameter portion 774 at the lower end of the cylindrical body 771, an injection portion 775 that opens at the lower end of the reduced-diameter portion 774, an air passage 776 communicating with the air inlet 772, and a water passage 777 communicating with the water inlet 773. The air passage 776 and the water passage 777 merge inside the reduced-diameter portion 774 to generate two fluids 778, which are then ejected from the injection portion 775.

[0027] The injection direction of the two fluids 778 is inclined with respect to the holding surface 500 of the chuck table 5. A rear plate 781 is positioned behind the nozzle 77 in the injection direction, parallel to the injection direction of the two fluids and at an acute angle with respect to the holding surface 500. The lower end of this rear plate 781 is bent toward the injection section 775 and is equipped with a parallel plate 782 formed substantially parallel to the reduced diameter section 774. A gap is formed between the parallel plate 782 and the reduced diameter section 774. The rear plate 781 and the parallel plate 782 may be in contact with the nozzle 77. Furthermore, the lower end of the side plate 784 may be provided with a flat plate 787 that extends parallel to the holding surface 500 and away from the nozzle 77.

[0028] Two side plates 784 are connected to both the left and right ends of the rear plate 781 (the front and back sides in the plane of Figure 3). The two side plates 784 are positioned opposite each other, with the nozzle 77 in between, and the rear plate 781 and the two side plates 784 surround the nozzle 77. The rear plate 781 and the side plates 784 may be formed as a single unit.

[0029] A front plate 785 is positioned in front of the diameter-reduced section 774 in the direction of ejection of the two fluids. The front plate 785 is a plate-shaped member facing the holding surface 500, and its surface direction is preferably between an angle perpendicular to the ejection direction of the two fluids 778 and an angle parallel to the holding surface 500.

[0030] When air flowing in from the air inlet 772 and water flowing in from the water inlet 773 merge inside the reduced diameter section 774 to generate a two-fluid mixture 778, which is then ejected from the injection section 775, the processing debris adhering to the holding surface 500 is scraped off and rises due to the two fluids. However, this rising processing debris collides with the front plate 785, thus preventing the mist containing the processing debris from scattering. Furthermore, when the two fluids 778 are ejected from the injection section 775, a negative pressure is created in the gap 783 between the tip of the reduced-diameter section 774 of the nozzle 22 and the tip of the parallel plate 782, and outside air 788 is introduced from the rear side of the rear plate 781. In other words, the gap 783 functions as an outside air introduction section. Note that the tip of the reduced-diameter section 774 and the tip of the parallel plate 782 may be in contact. When outside air is introduced from the rear side of the rear plate 781, that outside air is guided by the parallel plate 782 and ejected forward (towards the injection section 775). Therefore, it is possible to prevent the two fluids 778 and the mist of the two fluids reflected by the holding surface 500 from flowing backward, and thus it is possible to prevent processing chips from scattering backward. In this way, the scattering of the two fluids is prevented because the two fluids 778 and the reflected two fluids flow only forward. Therefore, the scattering prevention section 786 is formed by the front plate 785, the rear plate 781 and the side plate 784.

[0031] A gas-liquid separation unit 70 is installed on the side of the loading / unloading area 181 near the boundary between the loading / unloading area 181 and the polishing area 184, as shown in Figure 1. Alternatively, the gas-liquid separation unit 70 may be installed on the side of the loading / unloading area 181 near the boundary between the loading / unloading area 181 and the rough grinding area 182.

[0032] As shown in Figure 4, the gas-liquid separation unit 70 is equipped with a top plate 700, a plurality of side plates 701 hanging down from the top plate 700, and an inlet 702 for receiving scattered mist. The top plate 700 is shaped such that it does not overlap with the chuck table 5 when the chuck table 5 holding the workpiece 100 is positioned in the loading / unloading area 181, when viewed from the +Z side, and is shaped to effectively guide the two fluids 778 sprayed from the nozzle 77 and scattered during the cleaning of the workpiece 100 to the gas-liquid separation unit 70 for gas-liquid separation. In this embodiment, the top plate 700 is formed to be elongated in the X-axis direction toward the rotation center of the turntable 6.

[0033] The top plate 700 is formed in a shape in which a portion of a roughly rectangular shape (the portion located above the chuck table 5) is cut off. The cut-off portion has a first side 705 parallel to the X-axis direction and a hypotenuse 706 at an angle to the X-axis direction, with one end connected to the +X end of the first side 705. In addition, the top plate 700 has a second side 707 connected to the other end of the hypotenuse 706 and parallel to the X-axis direction, and opposing third side 708 and fourth side 709 parallel to the Y-axis direction. However, the shape of the top plate 700 is not limited to this. For example, instead of the first side 705 and the hypotenuse 706, it may have a portion formed in an arc shape along the periphery of the chuck table 5.

[0034] The side plate 701 is composed of a first side plate 710 formed on the +Y direction side, i.e., the upstream side in the direction of rotation of the chuck table 5; a second side plate 711 formed on the +X direction side, i.e., the outer circumference side of the orbital path of the chuck table 5 and the side furthest from the center of rotation of the chuck table 5; and a third side plate 712 formed on the side in the direction between the +X and -Y directions, refracted from the second side plate 711 and aligned with the outer circumference of the orbital path of the chuck table 5. The first side plate 710 is fixed to the side of the partition plate 161, for example, and the lower parts of the second side plate 711 and the third side plate 712 are fixed to the first device base 10, for example. In other words, the side plate 701 is arranged in the direction from which the mist is scattered and has the role of receiving the scattered mist. On the other hand, in the gas-liquid separation unit 70, there are no side plates on the -Y side, i.e., the side closer to the position where the two fluids 778 are injected from the nozzle 77, and on the -X side, i.e., the downstream side in the direction of rotation of the chuck table 5, thereby forming an inlet 702 for receiving mist. The first side plate 710 is not required, in which case the partition plate 161 performs the same role as the first side plate 710.

[0035] The upper edge of the inlet 702 of the gas-liquid separation unit 70 described above, i.e., the first edge 705, the slanted edge 706, and the second edge 707, is provided with a canopy 703 that extends downward. The canopy 703 may be positioned perpendicular to the top plate 700 in the -Z direction, or it may be inclined slightly toward the center of the chuck table 5 rather than in the -Z direction. It may also be curved. In the example shown in Figure 4, the canopy 703 has a shorter length in the Z direction on the -X side, i.e., the side closer to the nozzle 77, and a longer length in the Z direction on the +X side, i.e., the side further from the nozzle 77. In this way, the canopy 703 has a shorter length in the Z direction on the side closer to the nozzle 77, and the opening portion is formed to be longer in the Z-axis direction, thereby avoiding collision with the nozzle 77 and allowing for a wider range of motion of the nozzle 77. On the other hand, by making the length in the Z direction of the canopy 703 on the side further from the nozzle 77 longer, more mist can be contained. Furthermore, by housing the nozzle 77 inside the gas-liquid separation unit 70, passing under the overhang 703 which has a shorter length in the Z direction on the side closer to the nozzle 77, the conveyance of the workpiece 100 to the chuck table 5 is avoided.

[0036] As described above, the top plate 700 is formed in a shape with a portion of a roughly rectangular shape cut out. Therefore, the area below the uncut portion of the top plate 700 is a large-capacity area 704 with a larger volume that can accommodate more mist.

[0037] 2. Operation of the processing equipment (Carry-in process) The operation of the processing apparatus 1 when processing a workpiece 100 using the processing apparatus 1 configured as described above will now be explained. First, as the turntable 6 shown in Figure 1 rotates by a predetermined angle, the chuck table 5, on which the workpiece 100 is not placed, revolves and is positioned in the loading / unloading area 181.

[0038] Subsequently, the robot 155 unloads one workpiece 100 from the first cassette 173 and places the workpiece 100 on the table 153 in the temporary storage area 152. Next, while rotating the table 153, the top surface 101 of the workpiece 100 is imaged by the camera 154, three points on the outer circumference of the workpiece 100 are detected, and the center of the workpiece 100 is detected based on the positions of these three points.

[0039] Next, the first transport mechanism 171 uses suction to lift the upper surface 101 of the workpiece 100 and moves it above the chuck table 5 located in the loading / unloading area 181. Then, the workpiece 100 is placed on the holding surface 500 with its upper surface 101 facing upwards, so that the center of the chuck table 5 and the center of the workpiece 100 coincide. The workpiece 100 is then held in place by suction force acting on the holding surface 500 by opening the on / off valve 554 shown in Figure 2 and closing the on / off valves 555 and 556.

[0040] (Rough grinding process) After the workpiece 100 is held by suction on the holding surface 500 of the chuck table 5, the turntable 6 is rotated clockwise by a predetermined angle when viewed from the +Z side, causing the chuck table 5 to revolve and move the workpiece 100 held on the chuck table 5 below the rough grinding unit 30 to position it in the rough grinding area 182. At this time, the rough grinding unit 30 and the workpiece 100 are aligned so that when the rough grinding wheel 306 is lowered toward the workpiece 100 and the upper surface 101 of the workpiece 100 comes into contact with the rough grinding wheel 306, the lower surface of the rough grinding wheel 306 passes through the center of rotation of the workpiece 100.

[0041] The chuck table 5 is rotated, and the motor 302 rotates the rotating shaft 300 to rotate the rough grinding wheel 306. The motor 202 of the rough grinding feed unit 20 rotates the ball screw 200 to lower the rough grinding wheel, bringing the rough grinding wheel 306 into contact with the upper surface 101 of the workpiece 100.

[0042] After the workpiece 100 comes into contact with the rough grinding wheel 306, the rough grinding wheel 306 is further lowered in the -Z direction by a predetermined distance at a predetermined speed, thereby rough grinding the upper surface 101 of the workpiece 100 to a predetermined thickness. After the rough grinding is completed, the rough grinding feed unit 20 raises the rough grinding wheel 306, moving it away from the upper surface 101 of the workpiece 100.

[0043] (Finishing grinding process) Subsequently, the turntable 6 is rotated clockwise by a predetermined angle when viewed from the +Z side, causing the chuck table 5 to revolve and move the workpiece 100 held by the chuck table 5 below the finish grinding unit 31 to position it in the finish grinding area 183. When the finish grinding wheel 307 and the workpiece 100 come into contact, the outer circumference of the circle on the lower surface of the finish grinding wheel 307 is aligned to pass through the rotation center of the workpiece 100. Then, similar to the rough grinding process described above, the finish grinding feed unit 21 is used to lower the rotating finish grinding wheel 307 toward the rotating workpiece 100, bringing the finish grinding wheel 307 into contact with the workpiece 100.

[0044] After the finishing grinding wheel 307 comes into contact with the workpiece 100, the finishing grinding wheel 307 is further lowered in the -Z direction by a predetermined distance at a predetermined speed to finish grind the upper surface 101 of the workpiece 100. When the workpiece 100 reaches a predetermined finishing thickness, the finishing grinding feed unit 21 raises the finishing grinding wheel 307 to end the grinding.

[0045] (polishing process) Furthermore, by rotating the turntable 6 clockwise by a predetermined angle when viewed from the +Z side, the chuck table 5 is revolved, and the workpiece 100 held by the chuck table 5 is moved below the polishing unit 32. The workpiece 100 is aligned with the polishing pad 324 of the polishing unit 32 so that the polishing pad 324 contacts the entire upper surface 101 of the workpiece 100.

[0046] As the chuck table 5 is rotated at a predetermined rotational speed, the motor 322 rotates the spindle 320, causing the polishing pad 324 to rotate as well. The polishing unit 32 is then fed in the -Z direction by the polishing feed unit 25, causing the rotating polishing pad 324 to come into contact with the entire upper surface 101 of the workpiece 100.

[0047] When polishing is performed, a striped pattern may form on the upper surface 101 of the workpiece 100, and the formation of a striped pattern on the upper surface 101 may reduce the bending strength of the workpiece 100. Therefore, during polishing, the X-axis movement unit 24 moves the polishing unit 32 back and forth in the X-axis direction, moving the polishing pad 324 on the upper surface 101 of the workpiece 100 in the X-axis direction, thereby preventing the formation of a striped pattern on the upper surface 101.

[0048] (Workpiece cleaning process) After the polishing process described above is completed, the turntable 6 is rotated clockwise by a predetermined angle when viewed from the +Z side, and the polished workpiece 100 is moved to the loading / unloading area 181. In the loading / unloading area 181, the chuck table 5 is rotated, the nozzle 77 is lowered by the lifting actuator 74 shown in Figure 2, and the nozzle 77 is rotated by the swivel motor 71. Air and water are introduced into the nozzle 77 from the air source 75 and water source 76, respectively, and the two fluids 778 are sprayed from the spray section 775 shown in Figure 3 to clean the upper surface 101 of the workpiece 100. This cleaning process serves purposes such as preventing the transport pad of the second transport mechanism 172 from becoming contaminated when the processed workpiece 100 is transported from the processing area 92 to the loading / unloading area 91.

[0049] The two fluids 778 ejected from the nozzle 77 move from the center of the workpiece 100 towards the gas-liquid separation unit 70, enter the internal space of the gas-liquid separation unit 70 through the inlet 702 of the gas-liquid separation unit 70, and are separated into water and air upon contact with the side plates 701 and the top plate 700. Subsequently, the air is released into the atmosphere of the loading / unloading area 181 from the top of the inlet 702 and exhausted to the outside of the processing chamber through the exhaust port of a processing device (not shown), while the water is drained to the outside of the processing chamber 16 through the drain port 162.

[0050] After the two-fluid mist is removed from the space inside the loading / unloading area 181, the nozzle 77 is moved away from above the workpiece 100 by the lifting actuator 74 and the swivel motor 71. Then, the workpiece 100 is transported from the processing area 92 to the spinner cleaning unit 156 in the loading / unloading area 91 by the second transport mechanism 172 shown in Figure 1, and placed on the spinner table 157. As the spinner table 157 rotates, cleaning fluid is sprayed from the nozzle 158 onto the upper surface 101 of the workpiece 100, cleaning the upper surface 101. After the upper surface 101 is cleaned, the workpiece 100 is picked up by the robot 155 and stored in the second cassette 174.

[0051] (Retaining surface cleaning process) After the processed workpiece is unloaded from the chuck table 5 located in the loading / unloading area 181 by the second transport mechanism 172, if processing debris is attached to the holding surface 500, the holding surface 500 is cleaned by the cleaning unit 7.

[0052] As shown in Figure 5, the swivel motor 71 shown in Figure 2 positions the nozzle 77 above the center of the holding surface 500, and the lifting actuator 74 lowers the nozzle 77, bringing the lower end of the side plate closer to the holding surface 500. Then, the chuck table 5 is rotated, and the swivel motor 71 swivels the nozzle 77, causing it to oscillate radially over the holding surface 500 within the swivel range 79. At the same time, air is introduced from the air inlet 772 and water from the water inlet 773, and the two fluids are sprayed from the spray unit 775. As a result, the two fluids come into contact with the entire surface of the holding surface 500, and processing debris that has entered the porous member 50 can be scraped out. During this cleaning, the on / off valve 555 shown in Figure 2 is opened and the on / off valves 554 and 556 are closed to perform air blowing from the holding surface 500.

[0053] When the two fluids are sprayed toward the holding surface 500, the side plate 784 guides the mist of the two fluids reflected from the holding surface 500 forward to prevent scattering. Furthermore, as the mist guided forward hits the front plate 785 and falls, it prevents the mist mixed with processing debris from being scattered and can be removed to the outside of the holding surface. Therefore, it is possible to prevent processing debris from scattering and re-adhering to the holding surface 500.

[0054] Furthermore, when the two-fluid mixture 778 is ejected from the injection section 775, a negative pressure is created in the gap 783, drawing in outside air from the rear side of the rear plate 781. This outside air is then ejected towards the injection section 775 and guided in the direction of the two-fluid mixture 778 injection. Therefore, it is possible to prevent the two-fluid mixture 778 ejected from the injection section 775 and the two-fluid mixture mist that was diffusely reflected on the holding surface 500 from flowing backward (in the opposite direction to the injection direction of the two-fluid mixture 778), thereby effectively discharging processing debris from the holding surface 500.

[0055] Furthermore, even if the mist ejected from the nozzle 777 by the spraying section 775 and the mist removed from the holding surface 500 by the action of the scattering prevention section 786 were to rise upwards, the gas-liquid separation unit 70 is positioned in that direction, so the water mixed with processing debris can be caught and scattered. This water can then be discharged from the discharge section 81 located below the gas-liquid separation unit 70.

[0056] In this embodiment, the scattering prevention section is composed of the rear plate 781, the side plate 784, and the front plate 785. However, the scattering prevention section can function using only the rear plate 781 and the side plate 784, or only the front plate 785. [Explanation of Symbols]

[0057] 1: Processing equipment 10: First device base 11: Second device base 12: Column 1 13: Column 2 14: Column 3 150: First cassette mounting section 151: Second cassette mounting section 152: Temporary storage area 153: Table 154: Camera 155: Robot 156: Spinner cleaning unit 157: Spinner table 158: Nozzle 16: Processing room 161: Partition plate 162: Drain 17: Control Unit 171: First conveying mechanism 172: Second conveying mechanism 173: First cassette 174: Second cassette 181: Loading / unloading area 182: Rough grinding area 183: Finishing grinding area 184: Polishing area 20: Rough grinding feed unit 200: Ball screw 201: Guide rail 202: Motor 203: Lifting plate 204: Holder 21: Finishing grinding feed unit 24: X-axis movement unit 240: Ball screw 241: Guide rail 242: Motor 243: Movable plate 25: Polishing feed unit 250: Ball screw 251: Guide rail 252: Motor 253: Lifting plate 254: Holder 30: Rough grinding unit 300: Rotating shaft 301: Housing 302: Motor 303: Mount 304: Grinding wheel 305: Wheel base 306: Coarse grinding wheel 31: Finishing grinding unit 307: Finishing grinding wheel 32: Polishing Unit 320: Spindle 321: Housing 322: Motor 323: Mount 324: Polishing pad 5: Chuck Table 50: Porous member 500: Retaining surface 51: Frame 52: Support base 53: Shaft 54: Flow path 551, 552, 553: Flow control valves 554, 555, 556: Shut-off valves 557: Suction source, 558: Air source, 559: Water source 56: Motor 561: Shaft 562: Drive pulley 563: Driven pulley 564: Belt 6: Turntable 61: Bracket 62: Bearing 7: Washing Unit 70: Gas-liquid separation unit 700: Top panel 701: Side panel 702: Entrance 703: Canopy 704: Large capacity area 705: First side 706: Hypotenuse 707: Second side 708: Third side 709: Fourth side 710: 1st side plate 711: 2nd side plate 712: 3rd side plate 71: Swivel motor 72: Nozzle unit 73: Arm 74: Lifting actuator 75: Air source 76: Water source 77: Nozzle 771: Cylindrical body 772: Air inlet 773: Water inlet 774: Reduced diameter part 775: Injection section 776: Air passage 777: Water passage 778: Two fluids 781: Rear plate 782: Parallel plate 783: Gap (outside air intake) 784: Side plate 785: Front plate 786: Scatter prevention part 79: Turning range 81: Discharge section 91: Loading / unloading area 92: Processing area 100: Workpiece 101: Top surface

Claims

1. A processing apparatus comprising a chuck table that holds a workpiece by suction on a holding surface having irregularities of a porous member, and a processing unit that grinds or polishes the workpiece held by the holding surface, The cleaning unit includes a nozzle that sprays a two-fluid mixture of water and air in a spray direction inclined with respect to the holding surface, The cleaning unit includes a scattering prevention section that prevents the two fluids sprayed from the nozzle from scattering at least to the sides and rear in the spraying direction due to irregularities on the holding surface, The scattering prevention unit is, A front plate having a lower surface facing the holding surface and positioned on the front side in the direction of injection of the two fluids, the front plate prevents diffuse reflection of the two fluids by guiding the two fluids forward and causing them to descend upon contact with the front plate, A rear plate is positioned on the opposite side of the front plate, with the nozzle in between, A pair of side plates connected to both sides of the rear plate and surrounding the nozzle together with the rear plate, It comprises a flat plate connected to the lower end of each of the side plates, extending in a direction parallel to the holding surface and moving away from each other, Processing equipment.

2. The scattering prevention unit is, The lower end of the rear plate is further provided with a parallel plate that is parallel to the reduced diameter portion at the lower end of the nozzle and that forms a gap between it and the reduced diameter portion. The gap between the tip of the parallel plate and the tip of the reduced-diameter portion of the nozzle becomes a negative pressure when the two fluids are ejected from the injection portion provided at the lower end of the reduced-diameter portion, functioning as an outside air intake portion that introduces outside air from the rear side of the rear plate, and the parallel plate also functions as a guide that ejects the introduced outside air toward the injection portion side of the nozzle. The introduced outside air prevents the scattering of the two fluids backward in the injection direction due to the unevenness of the holding surface. The processing apparatus according to claim 1.

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