Processing device

Abstract

To clean one surface of a wafer without increasing processing time in a processing device and to prevent dust from getting between the one surface of the wafer and the holding surface of a chuck table.SOLUTION: A positioning unit (16) of a processing device (10) includes a positioning table (17) that holds a wafer (W) by suction using a suction surface (18) on which suction ports (44) are arranged, an air injection portion (56) that injects air from a plurality of injection ports (52) arranged to surround the center of the wafer held on the positioning table, and a base (20) that supports the positioning table. A control portion (11) injects air from the suction port toward the underside of the wafer held by a robot (25) and waiting above the positioning table, connects the suction port to a suction source (46), holds the wafer by suction using the suction surface, and injects air from the air injection portion to clean one side of the wafer.SELECTED DRAWING: Figure 5

Description

[Technical Field]

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

[0002] As disclosed in Patent Document 1, a grinding machine grinds wafers held on a chuck table with a grinding wheel. The automatic grinding machine includes a transport mechanism for transporting wafers to the chuck table, and removes wafers one by one from a cassette containing multiple wafers, transports them to the chuck table, and grinds them. The machine also includes a temporary placement table for positioning and temporarily placing the wafers removed from the cassette. The wafers temporarily placed on the temporary placement table are then transported to the chuck table by the transport mechanism.

[0003] When a wafer is transferred from the temporary placement table to the chuck table, water is supplied to the underside of the wafer to clean the underside of the wafer, as disclosed in Patent Document 2. By cleaning the underside of the wafer before transferring it to the chuck table, it is possible to prevent dust from getting between the underside of the wafer and the holding surface of the chuck table. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-018802 [Patent Document 2] Japanese Patent Publication No. 2022-035139 Summary of the Invention [Problem to be solved by the invention]

[0005] Cleaning the underside of the wafer when transferring it from the temporary placement table to the chuck table increases the time required to hold the wafer on the chuck table, thereby lengthening the processing time. Similar problems occur not only in grinding machines but also in polishing machines, cutting machines, and other processing machines equipped with temporary placement tables.

[0006] Therefore, the processing apparatus has a problem to be solved: how to clean one side of the wafer without increasing the processing time, and how to prevent dust from getting between the one side of the wafer and the holding surface of the chuck table. [Means for solving the problem]

[0007] One aspect of the present invention is a processing apparatus including a chuck table that holds a wafer, a processing unit that processes the wafer held on the chuck table, a transport mechanism that transports the wafer to the chuck table, a positioning unit that positions the wafer so that the wafer is transported to a predetermined position on the chuck table by the transport mechanism, a cassette stage that places a cassette containing the wafer, and a robot that holds the wafer stored in the cassette placed on the cassette stage and transports it to the positioning unit, wherein the positioning unit is in communication with a suction source. The system includes a positioning table that holds a wafer by suction using a suction surface on which suction ports are arranged, an air injection unit that has a plurality of injection ports arranged to surround the center of the wafer held on the positioning table and injects air from the injection ports, and a base that supports the positioning table, and a control unit that injects air from the suction ports toward the underside of a wafer that is held by the robot and waiting above the positioning table, connects the suction ports to a suction source, and holds the wafer by suction using the suction surface, and injects air from the air injection unit to clean one side of the wafer.

[0008] The positioning unit includes a rotation support part that rotatably supports the positioning table, the base on which the rotation support part is disposed, and a rotation drive part that rotates the positioning table, and the control part may inject air from the air injection part while rotating the positioning table that holds the wafer by suction with the suction surface.

[0009] In one embodiment of the configuration of the air injection unit, the robot has a robot hand that can enter below the wafer held by suction on the positioning table, and the robot hand is equipped with the air injection unit that injects air.

[0010] The control unit may move the robot hand, which is spraying air from the air spray unit, in parallel with the suction surface and away from the positioning table.

[0011] In one embodiment of the configuration of the air injection unit, the air injection unit is provided on the base. [Effects of the Invention]

[0012] According to the processing apparatus of the above aspect, when a wafer is transported to the positioning table provided in the positioning unit, one side of the wafer is cleaned by spraying air from the suction port of the positioning table and from the air spray section having multiple spray ports arranged to surround the center of the wafer held on the positioning table.Therefore, the wafer can be cleaned without extending the processing time, and processing can be performed without allowing dust to get between one side of the wafer and the holding surface of the chuck table. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. [Figure 2] FIG. 2 is a perspective view of a positioning unit provided in the processing device. [Figure 3] FIG. 2 is a perspective view of a robot provided in the processing device. [Figure 4]1A and 1B are diagrams illustrating a first embodiment of cleaning the bottom surface of a wafer in a processing apparatus. [Figure 5] 1A and 1B are diagrams illustrating a first embodiment of cleaning the bottom surface of a wafer in a processing apparatus. [Figure 6] 10A and 10B are diagrams illustrating a second embodiment of cleaning the bottom surface of a wafer in a processing apparatus. [Figure 7] 10A and 10B are diagrams illustrating a third embodiment of cleaning the bottom surface of a wafer in a processing apparatus. [Figure 8] 10A and 10B are diagrams illustrating a third embodiment of cleaning the bottom surface of a wafer in a processing apparatus. [Figure 9] 10A and 10B are diagrams illustrating a third embodiment of cleaning the bottom surface of a wafer in a processing apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, a processing device according to an embodiment of the present invention will be described with reference to the drawings. The X-axis, Y-axis, and Z-axis directions shown in each drawing are perpendicular to one another. The X-axis and Y-axis directions are horizontal. The Z-axis direction is the up-down direction, with the +Z direction side being the top and the -Z direction side being the bottom.

[0015] 1 is a grinding device that performs grinding on a workpiece, a wafer W. Note that application to a grinding device is just one example, and the present invention can also be applied to processing devices that perform processing other than grinding, such as a polishing device, a cutting device, and a laser processing device.

[0016] As shown in Figure 4 and subsequent figures, the wafer W is transported to the processing apparatus 10 with a protective tape T attached to one of its surfaces, the lower surface. Then, the other surface, the upper surface, of the wafer W is processed by the processing unit 35 of the processing apparatus 10. Therefore, when the lower surface of the wafer W is held or cleaned in the processing apparatus 10, the protective tape T is the object to be held or cleaned. Note that the present invention may also be used to process a wafer in which no protective member, such as protective tape T, is attached to one of its surfaces. In other words, the present invention can be applied to both a form in which a protective member is attached to one of the surfaces of the wafer and a form in which no protective member is attached.

[0017] The processing apparatus 10 is controlled by a control unit 11 and automatically performs a series of operations such as transport processing, grinding processing, and cleaning processing on the wafer W. The control unit 11 includes a processor and a memory unit, and the processor performs processing according to a program stored in the memory unit to control each unit of the processing apparatus 10.

[0018] The processing device 10 has a first base 12 located on the -Y direction side and a second base 13 located on the +Y direction side. The upper surface of the second base 13 is lower than the upper surface of the first base 12, and there is a step between the upper surfaces of the first base 12 and the second base 13.

[0019] Two cassette stages 14 are provided at different positions in the X-axis direction at the end of the first base 12 on the -Y direction side. A cassette 15 containing wafers W before grinding is placed on one of the cassette stages 14. A cassette 15 containing wafers W after grinding is placed on the other cassette stage 14.

[0020] A positioning unit 16 is provided at a position on the +Y direction side of the first base 12. The positioning unit 16 has a substantially circular positioning table 17. The positioning table 17 has a suction surface 18 on its upper surface that suction-holds the wafer W. A plurality of positioning pins 19 that are movable in the radial direction of the positioning table 17 are provided around the periphery of the positioning table 17. The positioning unit 16 has a base 20 that supports the positioning table 17, and the plurality of positioning pins 19 move along a plurality of grooves 21 formed in the base 20.

[0021] The positioning unit 16 has a function of positioning the wafer W so that the wafer W is transported to a predetermined position on the chuck table 27 by the transport mechanism 30. The wafer W is positioned so that the center of the positioning table 17 and the center of the wafer W coincide with each other by bringing a plurality of positioning pins 19 into contact with the outer periphery of the wafer W and holding the wafer W by suction on the suction surface 18 of the positioning table 17. The detailed structure and operation of the positioning unit 16 will be described later.

[0022] A cleaning unit 22 is provided on the first base 12 at a position on the −X direction side of the positioning unit 16. The cleaning unit 22 cleans the wafer W after grinding. The cleaning unit 22 suction-holds the wafer W on a cleaning table 23, and sprays cleaning water from a cleaning nozzle 24 while rotating the cleaning table 23 to clean the wafer W. After cleaning, air is blown onto the wafer W from the cleaning nozzle 24 to dry it.

[0023] A robot 25 is provided on the first base 12. The robot 25 has a configuration in which a robot hand 26 is attached to the tip of a movable arm made up of a multi-joint link, and transports the wafer W by moving the robot hand 26 that suction-holds the wafer W. The robot 25 removes the unground wafers W stored in the cassettes 15 placed on the cassette stage 14 one by one from the cassettes 15 and transports them to the positioning table 17 of the positioning unit 16. The robot 25 also transports the ground wafers W held on the cleaning table 23 of the cleaning unit 22 to store them in the cassettes 15 placed on the cassette stage 14. The detailed structure and operation of the robot 25 will be described later.

[0024] A chuck table 27 is disposed on the second base 13. The chuck table 27 has a holding surface on its upper surface that holds the wafer W. The holding surface of the chuck table 27 is formed of a porous plate, which is a porous material, and a large number of fine pores are provided on the holding surface. By operating a suction source (not shown) to suck air from the porous plate, a negative pressure is generated on the holding surface of the chuck table 27, and the wafer W is held by suction.

[0025] The chuck table 27 rotates about an axis extending in the Z-axis direction by driving a chuck table rotation mechanism 28 equipped with a motor. The chuck table 27 is also moved in the Y-axis direction by a Y-axis movement mechanism 29. By moving the chuck table 27 in the Y-axis direction by the Y-axis movement mechanism 29, the chuck table 27 is positioned at a loading / unloading position on the -Y-axis side and a processing position on the +Y-axis side. The loading / unloading position is a position where the wafer W is loaded and unloaded onto the chuck table 27 using a transport mechanism 30. The processing position is a position where the upper surface of the wafer W held on the chuck table 27 is ground using a processing unit 35.

[0026] The Y-axis moving mechanism 29 includes a Y-axis moving table 291 that supports the chuck table 27, supports the Y-axis moving table 291 movably along a pair of guide rails 292 extending in the Y-axis direction, and moves the Y-axis moving table 291 in the Y-axis direction by rotating a ball screw 293 extending in the Y-axis direction using a motor.

[0027] Although the processing device 10 is equipped with one chuck table 27, the number of chuck tables is not limited to one. For example, a turntable that rotates about an axis extending in the Z-axis direction may be provided, and multiple chuck tables may be arranged on the turntable. In this case, each chuck table is positioned at a processing position or a load / unload position by rotating the turntable.

[0028] The transport mechanism 30 includes a first transport unit 31 that transports the wafer W from the positioning unit 16 to the chuck table 27, and a second transport unit 32 that transports the wafer W from the chuck table 27 to the cleaning unit 22. The first transport unit 31 and the second transport unit 32 transport the wafer W with the chuck table 27 positioned at the carry-in / out position. The first transport unit 31 receives the wafer W before grinding from the positioning unit 16 and transports it to the chuck table 27. The second transport unit 32 receives the wafer W after grinding from the chuck table 27 and transports it to the cleaning unit 22.

[0029] Each of the first transfer unit 31 and the second transfer unit 32 includes a transfer pad capable of suction-holding the upper surface of the wafer W, a support arm extending horizontally to support the transfer pad, a rotation mechanism that rotates (pivots) the support arm about an axis extending in the Z-axis direction, and an elevation mechanism that moves the support arm up and down in the Z-axis direction. Each of the first transfer unit 31 and the second transfer unit 32 operates the support arm using the rotation mechanism and elevation mechanism to transfer the wafer W held by suction on the transfer pad.

[0030] The processing unit 35 performs grinding on the wafer W held on the chuck table 27 positioned at the processing position. The processing unit 35 is supported movably in the Z-axis direction (up and down direction) by a processing feed mechanism 34 provided on a column 33 erected on the upper surface of the second base 13.

[0031] The processing feed mechanism 34 includes a Z-axis moving table 341 that supports the processing unit 35, and supports the Z-axis moving table 341 movably along a pair of guide rails 342 extending in the Z-axis direction. The Z-axis moving table 341 is moved in the Z-axis direction by rotating a ball screw 343 extending in the Z-axis direction using a motor.

[0032] The processing unit 35 includes a spindle unit 37 supported via a housing 36 connected to a Z-axis moving table 341. The spindle unit 37 is, for example, an air spindle, and rotatably supports a spindle 38 inside the casing via high-pressure air. The spindle 38 is a shaft extending in the Z-axis direction, and a grinding wheel 39 is attached to a mount provided at the bottom end of the spindle 38. A plurality of grinding stones 40 are arranged in an annular shape on the underside of the grinding wheel 39. A motor provided in the spindle unit 37 rotates the spindle 38, thereby rotating the grinding wheel 39 equipped with the grinding stones 40.

[0033] A series of operations will be described when the processing apparatus 10 having the above configuration grinds the wafer W. The operations of each part of the processing apparatus 10 described below are performed under the control of the control unit 11, and unless a controlling entity is specified, it is assumed that the control unit 11 is in charge of the operations.

[0034] A cassette 15 containing wafers W before grinding is placed on the cassette stage 14. The control unit 11 causes the robot hand 26 of the robot 25 to hold the wafers W before grinding contained in the cassette 15 and transport the wafers W to the positioning unit 16 by operating the robot 25. After the robot 25 places the wafer W on the suction surface 18 of the positioning table 17, the control unit 11 causes the suction surface 18 to suction-hold the wafer W and moves the multiple positioning pins 19 toward the center of the positioning table 17 so that the multiple positioning pins 19 abut against the outer edge of the wafer W. This positioning operation aligns the center of the positioning table 17 with the center of the wafer W.

[0035] Next, the unground wafer W is transported from the positioning unit 16 to the chuck table 27 using the first transport unit 31 of the transport mechanism 30. The control unit 11 causes the upper surface of the wafer W on the positioning table 17 to be suction-held by the lower surface of the transport pad of the first transport unit 31, and then raises and rotates the support arm of the first transport unit 31 to move the transport pad above the chuck table 27, which is positioned at the load / unload position. Next, the control unit 11 lowers the support arm of the first transport unit 31 to place the wafer W on the holding surface of the chuck table 27, releases the suction-held state of the wafer W by the transport pad of the first transport unit 31, and causes the wafer W to be suction-held by the holding surface of the chuck table 27. In this manner, the wafer W is delivered to the chuck table 27.

[0036] The control unit 11 operates the Y-axis movement mechanism 29 to move the chuck table 27, which holds the wafer W before grinding, from the carry-in / out position to the processing position. Then, the wafer W on the chuck table 27 positioned at the processing position is ground using the processing unit 35. During grinding, the grinding wheel 39 and the wafer W are rotated relative to each other, and the grinding stone 40 is brought into contact with the upper surface of the wafer W. Specifically, the control unit 11 rotates the spindle 38 to rotate the grinding wheel 39, while lowering the grinding wheel 39 using the processing feed mechanism 34 to bring the grinding stone 40 closer to the wafer W held on the chuck table 27. The control unit 11 also controls the chuck table rotation mechanism 28 to rotate the chuck table 27. In this manner, the grinding wheel 39 equipped with the grinding stone 40 and the wafer W on the chuck table 27 are rotated relative to each other, and the grinding stone 40 is brought into contact with the upper surface of the wafer W, thereby grinding the wafer W. A processing fluid (grinding water) is supplied to the location where the grinding stone 40 contacts the wafer W.

[0037] When the wafer W has been ground to the desired thickness, the control unit 11 causes the processing feed mechanism 34 to raise the grinding wheel 39 and separate the grinding stone 40 from the upper surface of the wafer W. Next, the control unit 11 operates the Y-axis movement mechanism 29 to move the chuck table 27 holding the ground wafer W from the processing position to the carry-in / out position.

[0038] The ground wafer W is transported from the chuck table 27 to the cleaning unit 22 using the second transport unit 32 of the transport mechanism 30. The control unit 11 causes the upper surface of the wafer W on the chuck table 27 positioned at the load / unload position to be suction-held by the lower surface of the transport pad of the second transport unit 32, raises and rotates the support arm of the second transport unit 32, and moves the transport pad above the cleaning table 23 of the cleaning unit 22. Next, the control unit 11 lowers the support arm of the second transport unit 32 to place the wafer W on the holding surface of the cleaning table 23, releases the suction-held state of the wafer W by the transport pad of the second transport unit 32, and causes the wafer W to be suction-held by the holding surface of the cleaning table 23.

[0039] The control unit 11 rotates the cleaning table 23 holding the wafer W by suction, and causes cleaning water to be sprayed from the cleaning nozzle 24 to clean the wafer W. After cleaning, the cleaning nozzle 24 blows air onto the wafer W to dry it. The control unit 11 causes the robot hand 26 of the robot 25 to hold the wafer W by suction after cleaning and drying is complete, and operates the robot 25 to store the wafer W in the cassette 15.

[0040] In this manner, a series of processes are performed on the wafers W in the processing apparatus 10. In summary, the wafers W before grinding are taken out one by one from the cassette 15, transported to the positioning unit 16 and positioned, the positioned wafers W are transported from the positioning unit 16 to the chuck table 27, the wafers W on the chuck table 27 are ground by the processing unit 35, and the ground wafers W are cleaned by the cleaning unit 22 and then stored in the cassette 15.

[0041] When the wafer W before grinding is transported to the chuck table 27 by the first transport unit 31 of the transport mechanism 30, if there is dust on the underside (protective tape T) of the wafer W, the dust will get in between the wafer W and the holding surface of the chuck table 27. If the wafer W is ground by the processing unit 35 in this state, the thickness of the wafer W will become uneven. If water is supplied to the underside of the wafer W to clean it while it is being transported from the positioning unit 16 to the chuck table 27 in order to prevent this problem, it will take a long time for the wafer W to be held on the chuck table 27, lengthening the processing time.

[0042] To solve these problems, the processing apparatus 10 is configured to clean the underside of the wafer W without lengthening the processing time and to prevent dust from getting between the underside of the wafer W and the holding surface of the chuck table 27. Cleaning of the underside of the wafer W in the processing apparatus 10 will be described in detail below.

[0043] Fig. 2 shows the configuration of the positioning unit 16, and Fig. 3 shows the configuration of the robot 25. Figs. 4 and 5 show a first embodiment of underside cleaning of the wafer W performed using the positioning unit 16 and the robot 25 in the processing apparatus 10.

[0044] As shown in Figures 2, 4, and 5, the positioning unit 16 supports the positioning table 17 via a base 20 attached to the first base 12. A through-hole penetrating the base 20 in the Z-axis direction is formed, and a rotation support part 41 is disposed inside the through-hole. The rotation support part 41 is constituted by a bearing, and a rotation shaft 42 extending downward from the positioning table 17 is rotatably supported via the rotation support part 41. The rotation shaft 42 is connected to a rotation drive part 43 equipped with a motor. By rotating the rotation shaft 42 with the rotation drive part 43, the positioning table 17 to which the rotation shaft 42 is connected rotates.

[0045] A suction port 44 is formed on the suction surface 18 of the positioning table 17. As shown in Fig. 2, the suction port 44 has a shape in which an annular groove extending in the circumferential direction of the positioning table 17 and a linear groove extending in the radial direction of the positioning table 17 are connected.

[0046] The suction port 44 is connected to a suction source 46 and an air source 47 via a flow path 45 disposed inside the positioning table 17 and the rotary shaft 42. The suction source 46 includes a pump that sucks in air. The air source 47 includes a pump that delivers air.

[0047] By opening and closing an on-off valve 48 provided in the flow path 45, the suction port 44 can be switched between a state in which it is in communication with the suction source 46 and a state in which it is not in communication. By operating the suction source 46 and opening the on-off valve 48, air can be sucked through the suction port 44, causing a negative pressure to act on the suction surface 18. In other words, the wafer W placed on the positioning table 17 can be held by suction on the suction surface 18.

[0048] By opening and closing an on-off valve 49 provided in the flow path 45, the suction port 44 can be switched between a state in which it is in communication with the air source 47 and a state in which it is not in communication. By operating the air source 47 to open the on-off valve 49, air is sprayed from the suction port 44. When the suction hold of the wafer W by the positioning table 17 is released, the wafer W can be separated from the suction surface 18 by spraying air from the suction port 44. Furthermore, as will be described later, the underside of the wafer W can be cleaned by spraying air from the suction port 44 before the positioning table 17 holds the wafer W.

[0049] 3, the robot hand 26 provided to the robot 25 is a U-shaped robot hand having a notch 50 of a width that allows the positioning table 17 to pass through. By passing the positioning table 17 through the notch 50, the robot hand 26 can enter below the wafer W held by suction on the positioning table 17 (see FIG. 5).

[0050] 3, a plurality of ejection ports 52 are provided on the holding surface 51 of the robot hand 26. The ejection ports 52 are arranged to surround the center of the wafer W when the robot hand 26 is inserted below the wafer W held on the suction surface 18 of the positioning table 17 (the state shown in FIG. 5).

[0051] 4 and 5, the multiple nozzles 52 are connected to a suction source 54 and an air source 55 via flow paths 53 arranged inside the robot 25. The suction source 54 is equipped with a pump that sucks in air. The air source 55 is equipped with a pump that delivers air. The nozzles 52, flow paths 53, and air source 55 constitute an air injection unit 56 that injects air from the robot hand 26.

[0052] By opening and closing the on-off valve 57 provided in the flow path 53, the ejection port 52 can be switched between a state in which it is in communication with the suction source 54 and a state in which it is not in communication. By operating the suction source 54 to open the on-off valve 57, air can be sucked through the ejection port 52, causing a negative pressure to act on the holding surface 51. In other words, the wafer W can be sucked and held on the holding surface 51 of the robot hand 26.

[0053] By opening and closing an on-off valve 58 provided in the flow path 53, the jet port 52 is switched between a state in which it is in communication with the air source 55 and a state in which it is not in communication. By operating the air source 55 to open the on-off valve 58, air is jetted from the jet port 52. When the suction hold of the wafer W by the robot hand 26 is released, the wafer W can be separated from the holding surface 51 by jetting air from the jet port 52. Furthermore, as will be described later, the underside of the wafer W can be cleaned by jetting air from the jet port 52. In other words, the air jetting unit 56, as part of the positioning unit 16, has the function of cleaning the underside of the wafer W when the robot 25 transports the wafer W from the cassette 15 to the positioning table 17.

[0054] The robot 25 is equipped with a horizontal movement mechanism 60 that moves the robot hand 26 horizontally, and an elevation mechanism 61 that moves the robot hand 26 in the Z-axis direction. The horizontal movement mechanism 60 is composed of a multi-link movable arm that supports the robot hand 26, and changes the position of the robot hand 26 in the horizontal direction by relatively rotating multiple links provided on the movable arm. The elevation mechanism 61 supports the robot hand 26 relative to the movable arm so that it can be raised and lowered in the Z-axis direction.

[0055] The robot 25 further includes an inversion mechanism 62 that rotates the robot hand 26 around an axis that extends horizontally. By rotating the robot hand 26 with the inversion mechanism 62, the robot hand 26 can be switched between a state in which the holding surface 51 faces upward and a state in which the holding surface 51 faces downward. When the holding surface 51 faces upward, the robot hand 26 suction-holds the bottom surface of the wafer W (see FIG. 4). When the holding surface 51 faces downward, the robot hand 26 suction-holds the top surface of the wafer W (see FIG. 6).

[0056] The control unit 11 operates the robot 25 with the holding surface 51 of the robot hand 26 facing upward, and brings the holding surface 51 of the robot hand 26 close to the underside of the wafer W before grinding that is stored in the cassette 15. The control unit 11 opens the on-off valve 57 and closes the on-off valve 58, causing the suction source 54 to suck air from the nozzle 52. This causes the holding surface 51 of the robot hand 26 to suction and hold the underside of the wafer W. Next, the control unit 11 operates the robot 25 to transport the wafer W, the underside of which is suction-held by the robot hand 26, from the cassette 15 to the positioning unit 16.

[0057] 4, when the robot hand 26 moves to above the positioning table 17, the control unit 11 causes the lifting mechanism 61 to lower the robot hand 26, bringing the underside of the wafer W closer to the suction surface 18 of the positioning table 17. As the positioning table 17 passes through the cutout portion 50 of the robot hand 26, the wafer W can be brought closer to the positioning table 17 without the positioning table 17 and the robot hand 26 interfering with each other.

[0058] 4 shows a process of cleaning the underside of the wafer W by spraying air from the suction port 44 provided on the positioning table 17. The control unit 11 controls the lifting mechanism 61 to place the wafer W, which is suction-held by the robot hand 26, in a standby state above the positioning table 17. In other words, a gap is created between the underside of the wafer W and the suction surface 18 of the positioning table 17. The control unit 11 then closes the on-off valve 48 and the on-off valve 49 to spray air supplied from the air source 47 through the suction port 44 of the positioning table 17. The air sprayed from the suction port 44 is blown onto the underside of the wafer W to blow away any dust adhering to the underside of the wafer W. In this manner, the underside of the wafer W is cleaned by air blown from the suction port 44 of the positioning table 17.

[0059] While the underside of the wafer W is being cleaned by air blowing from the suction port 44 of the positioning table 17, the control unit 11 temporarily stops the lifting mechanism 61 to maintain a constant gap between the underside of the wafer W and the suction surface 18 of the positioning table 17. The time for the temporary stop is set to, for example, about 5 to 10 seconds.

[0060] Alternatively, the control unit 11 may operate the lifting mechanism 61 to lower the robot hand 26, gradually narrowing the gap between the underside of the wafer W and the suction surface 18 of the positioning table 17, while cleaning the underside of the wafer W with air blown from the suction port 44 of the positioning table 17. When cleaning the underside of the wafer W while lowering the robot hand 26, the control unit 11 may slow down the speed at which the robot hand 26 is lowered to ensure time for cleaning.

[0061] After cleaning the underside of the wafer W by air blowing from the positioning table 17, the control unit 11 opens the on-off valve 48 and closes the on-off valve 49 to cause the suction source 46 to suck air through the suction port 44 of the positioning table 17. Then, the control unit 11 operates the lifting mechanism 61 to lower the robot hand 26, and places the underside of the wafer W on the suction surface 18 of the positioning table 17. As a result, the underside of the wafer W is suction-held on the suction surface 18 of the positioning table 17.

[0062] The area of ​​the suction surface 18 of the positioning table 17 is smaller than the area of ​​the underside of the wafer W, and the air ejected from the suction ports 44 of the positioning table 17 in the state shown in Figure 4 is blown onto an area of ​​the underside of the wafer W that is closer to the center. In other words, the air blown from the suction ports 44 mainly cleans the area of ​​the underside of the wafer W that is held by the suction surface 18 of the positioning table 17. The area of ​​the underside of the wafer W that is outside the area held by the suction surface 18 is cleaned using air ejected from the air ejection unit 56 provided on the robot hand 26.

[0063] 5 shows a process of cleaning the underside of the wafer W by injecting air from the injection ports 52 of the air injection unit 56. After the underside of the wafer W is suction-held on the suction surface 18 of the positioning table 17, the control unit 11 closes the on-off valve 57 to release the suction-holding of the wafer W by the robot hand 26, and then operates the lifting mechanism 61 to lower the robot hand 26, bringing the robot hand 26 into a standby state below the wafer W. In other words, a gap is created between the underside of the wafer W and the holding surface 51 of the robot hand 26.

[0064] When releasing the suction hold of the wafer W by the robot hand 26, the control unit 11 closes the on-off valve 58 and causes air supplied from the air source 55 to be sprayed from the nozzle 52 of the robot hand 26. This allows the lower surface of the wafer W to be separated from the holding surface 51 of the robot hand 26.

[0065] 5, the control unit 11 causes the robot hand 26 to wait below the wafer W, forming a predetermined gap between the underside of the wafer W and the holding surface 51 of the robot hand 26, and continues to spray air from the nozzle 52 of the robot hand 26. As a result, the air sprayed from the nozzle 52 is blown onto the underside of the wafer W, blowing away dust adhering to the underside of the wafer W. In this way, the underside of the wafer W is cleaned by the air blown from the air spray unit 56 of the robot hand 26.

[0066] In other words, the underside of the wafer W can be cleaned not only by momentarily blowing air from the nozzle 52 to release the suction hold of the wafer W by the robot hand 26 (air blowing while the holding surface 51 is in close contact with the underside of the wafer W) but also by forming a gap between the underside of the wafer W and the holding surface 51 of the robot hand 26 as shown in Figure 5 and then blowing air from the nozzle 52.

[0067] 3, the robot hand 26 is provided with a plurality of jetting ports 52 around a notch 50 through which the positioning table 17 passes, and these plurality of jetting ports 52 are arranged to surround the center of the wafer W held on the positioning table 17. Therefore, by blowing air from the plurality of jetting ports 52 in the state shown in FIG. 5, it is possible to clean the area of ​​the underside of the wafer W outside the area held on the positioning table 17.

[0068] As described above, when the robot 25 transports the wafers W taken out one by one from the cassette 15 to the positioning unit 16, the underside of the wafer W is cleaned with air blown from the positioning table 17 or the robot hand 26. Therefore, after the positioning unit 16 positions the wafer W, at the stage when the transport mechanism 30 transports the wafer W from the positioning unit 16 to the chuck table 27, dust can be removed from the underside of the wafer W without performing a process of supplying water to clean the underside of the wafer W. Since the cleaning with air blown from the positioning table 17 or the robot hand 26 is performed as part of the process of transporting the wafer W by the robot 25, it can be completed efficiently in a short time. Therefore, in the processing apparatus 10, the time required for cleaning the underside of the wafer W is saved, thereby shortening the processing time.

[0069] In the positioning unit 16, the underside of the wafer W is suction-held against the suction surface 18 of the positioning table 17 to position the wafer W, and then, when the wafer W is handed over to the first transport section 31 of the transport mechanism 30, the on-off valve 48 is closed, the on-off valve 49 is opened, and air is blown from the suction port 44 to release the suction-holding of the wafer W by the positioning table 17.

[0070] However, if there is dust adhering to the underside of the wafer W before the underside of the wafer W is held on the suction surface 18 of the positioning table 17, the dust may become embedded in the underside of the wafer W due to the load applied when the wafer W is held on the positioning table 17. After the dust has embedded in the underside of the wafer W, even if air is blown from the suction port 44 to release the suction hold of the wafer W by the positioning table 17, the dust may not be able to be removed by the air blow.

[0071] 4, in this embodiment, air is blown from the suction port 44 of the positioning table 17 at a stage before the positioning table 17 holds the wafer W, thereby reliably removing the dust before it bites into the underside of the wafer W. In other words, by controlling the control unit 11 to execute the air blow for dust removal at a timing different from the air blow for releasing the suction hold of the wafer W by the positioning table 17, an excellent cleaning effect for the wafer W is achieved.

[0072] In addition, by combining the air blow from the positioning table 17 that holds the central portion of the wafer W with the air blow from the robot hand 26 that holds the wafer W in an area outside the positioning table 17, it is possible to obtain a cleaning effect on the entire underside of the wafer W.

[0073] FIG. 6 shows a second embodiment of the underside cleaning of a wafer W in the processing apparatus 10. In this embodiment, an air injection unit 70 is provided on the base 20 of the positioning unit 16. The air injection unit 70 is composed of a plurality of injection ports 71 formed on the upper surface of the base 20, a flow path 72 connecting the injection ports 71 to the air source 47, and the air source 47. The air source 47 is connected to both the suction port 44 of the positioning table 17 and the injection ports 71 of the base 20, and the positioning table 17 and the base 20 share the air source 47. The plurality of injection ports 71 are arranged to surround the center of the wafer W held on the positioning table 17. For example, in the base 20 shown in FIG. 2, the plurality of injection ports 71 are arranged dispersedly in the area between the plurality of grooves 21 extending radially outward from the positioning table 17. By opening and closing the on-off valves 73 provided in the flow paths 72, each of the nozzles 71 of the base 20 can be switched between a state in which it is in communication with the air source 47 and a state in which it is not in communication. By operating the air source 47 to open the on-off valves 73, air is sprayed from the nozzles 71.

[0074] 6, when transferring the wafer W from the cassette 15 to the positioning unit 16, the control unit 11 causes the inverting mechanism 62 to turn the holding surface 51 of the robot hand 26 downward, opens the on-off valve 57, closes the on-off valve 58, and causes the suction source 54 to suck air from the nozzle 52. As a result, the holding surface 51 of the robot hand 26 holds the upper surface of the wafer W by suction. Next, the control unit 11 operates the robot 25 to transfer the wafer W, the upper surface of which is held by suction by the robot hand 26, from the cassette 15 to the positioning unit 16.

[0075] 6 shows a process of cleaning the underside of the wafer W by spraying air from the suction port 44 of the positioning table 17 and from the nozzle 71 of the air spray unit 70 provided on the base 20. The control unit 11 lowers the robot hand 26 using the lifting mechanism 61, and places the wafer W held by the robot hand 26 in a standby state above the positioning table 17. In other words, a gap is created between the underside of the wafer W and the suction surface 18 of the positioning table 17.

[0076] Then, the control unit 11 closes the on-off valve 48 and closes the on-off valve 49 to cause the air supplied from the air source 47 to be sprayed from the suction port 44 of the positioning table 17. The control unit 11 also closes the on-off valve 73 to cause the air supplied from the air source 47 to be sprayed from the injection port 71 of the base 20. The air sprayed from the suction port 44 of the positioning table 17 and the air sprayed from the injection port 71 of the base 20 are blown onto the underside of the wafer W, blowing away dust adhering to the underside of the wafer W. In this way, the underside of the wafer W is cleaned by simultaneously blowing air from the suction port 44 of the positioning table 17 and the air spray unit 70 of the base 20.

[0077] While the underside of the wafer W is being cleaned by air blowing from the suction port 44 of the positioning table 17 and the injection port 71 of the base 20, the control unit 11 temporarily stops the lifting mechanism 61 to maintain a constant gap between the underside of the wafer W and the suction surface 18 of the positioning table 17. The time for the temporary stop is set to, for example, about 5 to 10 seconds.

[0078] Alternatively, the control unit 11 may operate the lifting mechanism 61 to lower the robot hand 26, gradually narrowing the gap between the underside of the wafer W and the suction surface 18 of the positioning table 17, while cleaning the underside of the wafer W with air blown from the suction port 44 of the positioning table 17 and the injection port 71 of the base 20. When cleaning the underside of the wafer W while lowering the robot hand 26, the control unit 11 may slow down the speed at which the robot hand 26 is lowered to ensure time for cleaning.

[0079] As described above, in the second embodiment of cleaning the underside of the wafer W, when the robot 25 transports the wafer W from the cassette 15 to the positioning unit 16, the underside of the wafer W is cleaned by air blowing from the positioning table 17 and air blowing from the base 20, thereby saving the time required to clean the underside of the wafer W in the processing apparatus 10 and achieving an effect of shortening the processing time. In particular, by simultaneously blowing air from the positioning table 17 and air blowing from the base 20, the time required to clean the underside of the wafer W can be further shortened.

[0080] The entire underside of the wafer W can be cleaned by combining air blowing from the positioning table 17 that holds the central portion of the wafer W and air blowing from the base 20 that faces the underside of the wafer W in the area outside the positioning table 17.

[0081] Since the robot hand 26 can clean the entire underside of the wafer W while suction-holding the upper surface of the wafer W, there is increased freedom in selecting the shape of the robot hand 26. For example, instead of the U-shaped robot hand 26 shown in Fig. 3, it is possible to use a robot hand that does not have a cutout portion for passing the positioning table 17 through.

[0082] 6 is completed, the control unit 11 opens the on-off valve 48, closes the on-off valve 49, switches the suction port 44 of the positioning table 17 from air injection to air suction, and lowers the robot hand 26 to suck and hold the underside of the wafer W on the suction surface 18. As a result, the wafer W is held on the positioning table 17 with any dust removed from its underside.

[0083] With the wafer W held on the positioning table 17, the control unit 11 may rotate the positioning table 17, which is rotatably supported via the rotation support unit 41, by the rotation drive unit 43 while spraying air from the spray nozzles 71 of the base 20. By rotating the wafer W held by suction on the positioning table 17 relative to the base 20, air sprayed from the multiple spray nozzles 71 arranged on the base 20 is sprayed evenly onto the underside of the wafer W. As a result, the cleaning effect of the underside of the wafer W by air blown from the air spray unit 70 can be improved.

[0084] 7 to 9 show a third embodiment of cleaning the underside of a wafer W in the processing apparatus 10. The third embodiment has a common configuration with the first embodiment, and similarly to the first embodiment, the underside of the wafer W is cleaned by using a combination of air blown from the suction port 44 of the positioning table 17 and air blown from the air injection unit 56 of the robot hand 26.

[0085] 7 shows a process of cleaning the underside of the wafer W by spraying air from the suction port 44 of the positioning table 17. This process is similar to the process in the first embodiment shown in FIG. 4. The control unit 11 controls the lifting mechanism 61 to make the wafer W, which is held by suction by the robot hand 26, wait above the positioning table 17, and create a gap between the underside of the wafer W and the suction surface 18 of the positioning table 17.

[0086] In this state, the control unit 11 temporarily stops the lowering of the robot hand 26 by the lifting mechanism 61. The time for this temporary stop is set to, for example, about 5 to 10 seconds. Then, the control unit 11 closes the on-off valve 48, closes the on-off valve 49, and causes air supplied from the air source 47 to be ejected from the suction port 44. The air ejected from the suction port 44 is blown onto the underside of the wafer W, blowing away any dust adhering to the underside of the wafer W. In this way, the underside of the wafer W is cleaned by the air blown from the positioning table 17.

[0087] After cleaning the underside of the wafer W by blowing air from the positioning table 17, the control unit 11 opens the on-off valve 48 and closes the on-off valve 49 to cause the suction source 46 to suck air through the suction port 44 of the positioning table 17. The control unit 11 also operates the lifting mechanism 61 to lower the robot hand 26, and places the underside of the wafer W on the suction surface 18 of the positioning table 17. As a result, the underside of the wafer W is suction-held on the suction surface 18 of the positioning table 17.

[0088] 8 and 9 show a process of cleaning the underside of the wafer W by injecting air from the air injection unit 56 provided on the robot hand 26. Once the underside of the wafer W is suction-held on the suction surface 18 of the positioning table 17, the control unit 11 closes the on-off valve 57 to release the suction-holding of the wafer W by the robot hand 26, and then operates the lifting mechanism 61 to lower the robot hand 26, causing the robot hand 26 to wait below the wafer W, and leaving a gap between the underside of the wafer W and the holding surface 51 of the robot hand 26.

[0089] When releasing the suction hold of the wafer W by the robot hand 26, the control unit 11 closes the on-off valve 58 and causes air supplied from the air source 55 to be sprayed from the nozzle 52 of the robot hand 26. This allows the lower surface of the wafer W to be separated from the holding surface 51 of the robot hand 26.

[0090] 8, the control unit 11 causes the robot hand 26 to wait below the wafer W, forming a predetermined gap between the underside of the wafer W and the holding surface 51 of the robot hand 26, and continues to spray air from the nozzle 52 of the robot hand 26. Furthermore, while spraying air from the nozzle 52 of the robot hand 26, the control unit 11 causes the rotation drive unit 43 to rotate the positioning table 17, which is rotatably supported via the rotation support unit 41.

[0091] 9, while continuing to eject air from the nozzle 52 of the robot hand 26 and rotate the positioning table 17 by the rotation drive unit 43, the control unit 11 operates the horizontal movement mechanism 60 of the robot 25 to move the robot hand 26, which is ejecting air from the nozzle 52, parallel to the suction surface 18 of the positioning table 17. The direction of movement of the robot hand 26 by the horizontal movement mechanism 60 at this time is along the longitudinal direction of the cutout portion 50, more specifically, the direction in which the positioning table 17 passes through the opening of the cutout portion 50 (see FIG. 3) formed on the tip side of the robot hand 26. The robot hand 26 is then moved horizontally until it is separated from below the wafer W.

[0092] In this way, by rotating the wafer W held by suction on the positioning table 17 relative to the robot hand 26 and moving the robot hand 26 parallel to the suction surface 18 of the positioning table 17, air jetted from the multiple jetting ports 52 arranged on the robot hand 26 is evenly sprayed onto the underside of the wafer W. As a result, the cleaning effect of the underside of the wafer W by the air blown from the air jetting unit 56 can be improved.

[0093] As described above, in each embodiment of cleaning the underside of the wafer W in the processing apparatus 10, during the process in which the robot 25 transports the wafer W from the cassette 15 to the positioning table 17 of the positioning unit 16, the underside of the wafer W is cleaned by spraying air from the suction port 44 of the positioning table 17, spraying air from the air spray unit 56 of the robot hand 26, or spraying air from the air spray unit 70 of the base 20. This eliminates the need for a dedicated cleaning process in which water is supplied to the underside of the wafer W to clean it while the wafer W is being transported from the positioning unit 16 to the chuck table 27 using the transport mechanism 30, thereby saving the time required for cleaning the underside of the wafer W. As a result, the underside of the wafer W can be cleaned without increasing the processing time in the processing apparatus 10. Furthermore, the wafer W can be held on the chuck table 27 without introducing any foreign matter, thereby achieving excellent processing quality.

[0094] The air jet from the suction port 44 of the positioning table 17 is used not only to clean the underside of the wafer W but also to release the suction hold of the wafer W by the suction surface 18. The air jet from the air jet unit 56 of the robot hand 26 is used not only to clean the underside of the wafer W but also to release the suction hold of the wafer W by the holding surface 51. In this way, the positioning table 17 and the robot hand 26 use the air blowing structure for releasing the suction hold of the wafer W to clean the underside of the wafer W with air, so that the above-mentioned effect can be obtained by setting the control program of the control unit 11 (more specifically, by setting the timing of air blowing) without adding a complex structure to the processing apparatus 10.

[0095] Each embodiment of cleaning the underside of a wafer W has in common the fact that one side (underside) of the wafer W is cleaned by performing a first operation of spraying air from the suction port 44 of the positioning table 17 toward the underside of the wafer W held by the robot 25 and waiting above the positioning table 17, a second operation of connecting the suction port 44 of the positioning table 17 to the suction source 46 to hold the wafer W by suction using the suction surface 18, and a third operation of spraying air from the air spray unit 56 or the air spray unit 70.

[0096] In the first embodiment (FIGS. 4 and 5) and the third embodiment (FIGS. 7 to 9), the control unit 11 controls so that a series of operations are performed in the order of the first operation, the second operation, and the third operation. In the second embodiment (FIG. 6), the control unit 11 controls so that the first operation and the third operation are performed simultaneously, and then the second operation is performed. In this way, it is sufficient to satisfy at least the requirement that the first operation of injecting air from the suction port 44 of the positioning table 17 be performed before the second operation of suction-holding the wafer W by the suction surface 18, and there is a degree of freedom in selecting the timing of performing the third operation of injecting air from the air injection units 56, 70.

[0097] The processing apparatus 10 of the above embodiment is an example applied to a grinding apparatus, but is not limited thereto. The present invention can be applied to any processing apparatus that transports wafers from a cassette to a positioning unit, positions them, and then transports the wafers from the positioning unit to a chuck table to process the wafers. For example, the present invention can be applied to various processing apparatuses that perform polishing, cutting, laser processing, etc. on wafers. These processing apparatuses are equipped with a positioning unit and a chuck table, and by applying the present invention, the same effects as those of the processing apparatus 10 of the above embodiment can be obtained.

[0098] The embodiments of the present invention are not limited to the above-described embodiments and modifications, and may be variously changed, substituted, or modified without departing from the spirit of the technical idea of ​​the present invention. Furthermore, if the technical idea of ​​the present invention can be realized in a different way due to technological advances or derived technologies, it may be implemented using that method. Therefore, the claims cover all embodiments that may fall within the scope of the technical idea of ​​the present invention. [Industrial Applicability]

[0099] As described above, the processing apparatus of the present invention can clean one side of a wafer with excellent time efficiency, shortening the time required for processing the wafer, and has a significant effect on improving productivity in various processing apparatuses. [Explanation of symbols]

[0100] 10: Processing equipment 11: Control section 14: Cassette Stage 15: Cassette 16: Positioning unit 17: Positioning table 18: Suction surface 19: Locating pin 20: Bass 22: Cleaning unit 25: Robot 26: Robot Hand 27: Chuck table 28: Chuck table rotation mechanism 29:Y-axis movement mechanism 30:Transport mechanism 31: First conveying section 32: Second conveying section 34: Processing feed mechanism 35: Processing unit 39: Grinding wheel 40: Grinding wheel 41: Rotation support part 42: Rotation axis 43: Rotation drive unit 44: Suction port 45: Flow path 46: Suction source 47: Air source 48: On-off valve 49: On-off valve 50: Notch 51: Holding surface 52: Nozzle 53: Flow path 54: Suction source 55: Air source 56: Air injection part 57: On-off valve 58: On-off valve 60: Horizontal movement mechanism 61: Lifting mechanism 62: Reversing mechanism 70: Air injection part 71: Nozzle 72: Flow path 73: On-off valve T: Protective tape W: wafer

Claims

1. A processing apparatus comprising: a chuck table for holding a wafer; a processing unit for processing the wafer held on the chuck table; a transport mechanism for transporting the wafer to the chuck table; a positioning unit for positioning the wafer so that the wafer is transported to a predetermined position on the chuck table by the transport mechanism; a cassette stage for placing a cassette containing a wafer thereon; and a robot for holding the wafer contained in the cassette placed on the cassette stage and transporting the wafer to the positioning unit, The positioning unit includes a positioning table that holds a wafer by suction using a suction surface on which suction ports communicating with a suction source are arranged, an air injection unit that has a plurality of injection ports arranged so as to surround the center of the wafer held on the positioning table and injects air from the injection ports, and a base that supports the positioning table; The control unit injects air from the suction port toward the underside of the wafer held by the robot and waiting above the positioning table, connects the suction port to a suction source to suck and hold the wafer by the suction surface, and injects air from the air injection unit to clean one side of the wafer.

2. the positioning unit includes a rotation support part that rotatably supports the positioning table, the base on which the rotation support part is disposed, and a rotation drive part that rotates the positioning table; 2. The processing apparatus according to claim 1, wherein the control unit injects air from the air injection unit while rotating the positioning table that holds the wafer by suction on the suction surface.

3. 3. The processing device according to claim 1, wherein the robot has a robot hand capable of moving under the wafer held by suction on the positioning table, and the robot hand is provided with the air injection unit for injecting air.

4. 4. The processing apparatus according to claim 3, wherein the control unit moves the robot hand, which is injecting air from the air injection unit, in parallel with the suction surface and moves the robot hand away from the positioning table.

5. 3. The processing device according to claim 1, wherein the air injection unit is provided on the base.

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