Method and device for processing plate-like workpiece

Abstract

To prevent processed waste from existing between a plate-like workpiece and a holding surface when at least two plate-like workpieces having different shapes are selectively held to be processed.SOLUTION: In the invention, one of a plate-like workpiece (W11) and a plate-like workpiece (W12) having a shape different from a shape of the plate-like workpiece is held by a chuck table (61) to be ground by grinding stones (47). The chuck table includes: a first holding surface (67) which suctions and holds the plate-like workpiece (W11); and a second holding surface (68) which is located at the outer side of the first holding surface to suction and hold the plate-like workpiece (W12). The plate-like workpiece (W11) is suctioned and held by the first holding surface and then the plate-like workpiece (W11) is ground with a fluid jetted from the second holding surface.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a method and apparatus for machining a plate-shaped workpiece using a chuck table for holding the plate-shaped workpiece. [Background technology]

[0002] Patent Documents 1 and 2 disclose grinding devices in which a plate-shaped workpiece is held on a chuck table and ground with a grinding wheel. The chuck tables in Patent Documents 1 and 2 are capable of changing the area or shape of the holding surface that holds the plate-shaped workpiece so that at least two plate-shaped workpieces with different areas can be selected and held. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2017-074628 [Patent Document 2] Japanese Patent Application Publication No. 03-032538 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Documents 1 and 2, when one of two plate-shaped workpieces is being ground, there is a portion that is exposed on the holding surface of the chuck table. As a result, grinding chips may adhere to the exposed holding surface, and when the other plate-shaped workpiece is ground, the grinding chips may get between the other plate-shaped workpiece and the holding surface, resulting in a problem of reduced grinding accuracy (processing accuracy) of the other plate-shaped workpiece.

[0005] The present invention has been made in consideration of these points, and one of its objects is to provide a method and apparatus for processing plate-shaped workpieces that can prevent processing chips from getting between the plate-shaped workpiece and the holding surface when selectively holding and processing at least two plate-shaped workpieces with different shapes. [Means for solving the problem]

[0006] One embodiment of the present invention relates to a method for machining a plate-shaped workpiece, which comprises holding one of at least two plate-shaped workpieces, a first plate-shaped workpiece and a second plate-shaped workpiece having a different shape from the first plate-shaped workpiece, on a universal chuck table and machining the plate-shaped workpiece with a machining tool. The universal chuck table has a first holding surface for suction-holding the first plate-shaped workpiece, and a second holding surface outside the first holding surface for suction-holding the second plate-shaped workpiece, and the method comprises a holding step of suction-holding the first plate-shaped workpiece on the first holding surface, and a machining step of machining the first plate-shaped workpiece while spraying a fluid from the second holding surface after the holding step.

[0007] Another aspect of the present invention is a method for machining a plate-shaped workpiece, which includes holding one of at least two plate-shaped workpieces, a first plate-shaped workpiece and a second plate-shaped workpiece having a shape different from that of the first plate-shaped workpiece, on a universal chuck table and machining the plate-shaped workpiece, wherein the universal chuck table has a common holding surface that can attract the first plate-shaped workpiece and the second plate-shaped workpiece, a first work holding surface that holds the first plate-shaped workpiece outside the common holding surface, and a second work holding surface that holds the second plate-shaped workpiece outside the common holding surface. and a second workpiece holding surface for holding a first plate-shaped workpiece, the holding process comprising: a common holding surface and the first workpiece holding surface, or a common holding surface and the second workpiece holding surface, and a machining process in which, when the first plate-shaped workpiece is held in the holding process, a fluid is sprayed from the second workpiece holding surface while machining the first plate-shaped workpiece, and when the second plate-shaped workpiece is held in the holding process, a fluid is sprayed from the first workpiece holding surface while machining the second plate-shaped workpiece.

[0008] A further aspect of the present invention is a method for machining a plate-shaped workpiece, in which one of at least two plate-shaped workpieces, a first plate-shaped workpiece and a second plate-shaped workpiece having a shape different from that of the first plate-shaped workpiece, is held on a universal chuck table and the plate-shaped workpiece is machined with a machining tool, the universal chuck table having a common holding surface that can suck the first plate-shaped workpiece and the second plate-shaped workpiece, a first work holding surface that holds the first plate-shaped workpiece outside the common holding surface, and a second work holding surface that holds the second plate-shaped workpiece outside the common holding surface, the method comprising: a holding step of sucking and holding the first plate-shaped workpiece or the second plate-shaped workpiece on the common holding surface; and a step of, after the holding step, sucking and holding the first plate-shaped workpiece. a determining step of determining whether the plate-shaped work is the first plate-shaped work or the second plate-shaped work based on the pressure value applied to the first work-holding surface or the second work-holding surface by connecting the work-holding surface or the second work-holding surface to a suction source, or based on the pressure value applied to the first work-holding surface or the second work-holding surface by connecting the first work-holding surface or the second work-holding surface to a fluid supply source; and a machining step of machining the first plate-shaped work while spraying fluid from the second work-holding surface if the plate-shaped work is determined to be the first plate-shaped work in the determining step, or machining the second plate-shaped work while spraying fluid from the first work-holding surface if the plate-shaped work is determined to be the second plate-shaped work in the determining step.

[0009] A processing apparatus according to one embodiment of the present invention is a processing apparatus that carries out the above-mentioned method for processing plate-shaped workpieces, and includes a universal chuck table that holds one of at least two plate-shaped workpieces, a first plate-shaped workpiece and a second plate-shaped workpiece having a different shape from the first plate-shaped workpiece, using a holding surface, a processing unit that processes the plate-shaped workpiece held on the universal chuck table, a change mechanism that can change the shape of the holding surface, and a fluid ejection mechanism that ejects a fluid from a portion of the holding surface that is exposed to the outside of the first plate-shaped workpiece or the second plate-shaped workpiece held on the universal chuck table. [Effects of the Invention]

[0010] According to the present invention, when a plate-shaped workpiece is held by suction and machined, a fluid is ejected from the holding surface exposed to the outside of the plate-shaped workpiece, thereby preventing grinding chips from adhering to the holding surface exposed during machining. This makes it possible to prevent machining chips from getting between the holding surface and the plate-shaped workpiece when holding plate-shaped workpieces of different shapes by suction, and maintain good machining accuracy for the plate-shaped workpieces being held by suction. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic perspective view of a grinding device according to a first embodiment. [Figure 2] FIG. 4 is an explanatory side view showing a state in which a first plate-shaped workpiece is held by the holding device. [Figure 3] FIG. 10 is an explanatory side view showing a state in which a second plate-shaped workpiece is held by the holding device. [Figure 4] FIG. 10 is a side view illustrating a determination step in the first embodiment. [Figure 5] FIG. 10 is an explanatory side view showing another example of the determination step in the first embodiment. [Figure 6] FIG. 3 is a side view for explaining a grinding step in the first embodiment. [Figure 7] FIG. 10 is a partial plan view for explaining a holding device according to a second embodiment. [Figure 8] FIG. 10 is a partial plan view for explaining an example of a grinding method according to the second embodiment. [Figure 9] FIG. 10 is a partial plan view for explanation showing another example of the grinding method in the second embodiment. [Figure 10] FIG. 10 is a partial plan view for explaining a holding device according to a third embodiment. [Figure 11] FIG. 11 is a partial plan view for explaining an example of a grinding method according to the third embodiment. [Figure 12] FIG. 11 is a partial plan view for explanation showing another example of the grinding method in the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] [First embodiment] Hereinafter, a method and apparatus for processing a plate-shaped workpiece according to a first embodiment will be described with reference to the accompanying drawings. Fig. 1 is a schematic perspective view of a grinding apparatus according to the first embodiment, which is an example of a processing apparatus to which the present invention is applied.

[0013] The X-axis, Y-axis, and Z-axis directions of the grinding apparatus 1 are perpendicular to one another. The X-axis and Y-axis directions are approximately horizontal, and the Z-axis direction is an up-down direction (vertical direction). Of the two arrows indicating the X-axis direction, the +X side is the front and the -X side is the rear. Of the two arrows indicating the Y-axis direction, the +Y side is the left and the -Y side is the right. Of the two arrows indicating the Z-axis direction, the +Z side is the up and the -Z side is the down.

[0014] As shown in Fig. 1, the grinding apparatus 1 performs grinding on a plate-shaped workpiece (first plate-shaped workpiece) W11 and a plate-shaped workpiece (second plate-shaped workpiece) W12 held on a universal chuck table 61 (hereinafter referred to as "chuck table 61") described below. Each of the plate-shaped workpieces W11 and W12 is a substantially circular wafer. Each of the plate-shaped workpieces W11 and W12 may be any plate-shaped workpiece that can be ground, and may be a semiconductor substrate made of silicon, gallium arsenide, or the like, or an inorganic material substrate made of ceramic, glass, sapphire, or the like, or may even be a package substrate for a semiconductor product.

[0015] In this embodiment, the plate-shaped workpieces W11 and W12 have different shapes, with the plate-shaped workpiece W12 having a larger diameter than the plate-shaped workpiece W11. For example, the plate-shaped workpiece W11 can be a 6-inch wafer and the plate-shaped workpiece W12 can be an 8-inch wafer, or the plate-shaped workpiece W11 can be an 8-inch wafer and the plate-shaped workpiece W12 can be a 12-inch wafer. In the grinding process, the upper surfaces of the plate-shaped workpieces W11 and W12 are the surfaces to be ground, and protective tape T is attached to the lower surfaces of the plate-shaped workpieces W11 and W12.

[0016] A rectangular opening 13 extending in the X-axis direction is formed in the upper surface of the base 10 of the grinding device 1. This opening 13 is covered by a moving plate 17 that can move in the X-axis direction together with the chuck table 61, and a bellows-shaped waterproof cover 18.

[0017] A table moving mechanism 20 that moves the chuck table 61 in the X-axis direction is provided below the waterproof cover 18. The table moving mechanism 20 includes a pair of guide rails 25 extending in the X-axis direction and a ball screw 26, and a moving base 27 is supported so as to be movable along the guide rails 25. The ball screw 26 is threadedly engaged with a threaded portion (not shown) of the moving base 27, and when the ball screw 26 is rotated by operation of the motor 24, the moving base 27 moves in the X-axis direction.

[0018] Further, a table rotation mechanism 30 that rotates and drives the chuck table 61 is provided below the waterproof cover 18. The table rotation mechanism 30 has a table rotation shaft rotatably supported via bearings inside a support frame 31 that is supported on the movable base 27. An endless belt 36 is wound around a driven pulley 33 provided on the outer surface of the table rotation shaft and a drive pulley 35 that is rotated by a motor 34. When the drive pulley 35 is rotated by operation of the motor 34, the rotation is transmitted to the driven pulley 33 via the endless belt 36, and the table rotation shaft is rotated.

[0019] Next, we will explain the grinding mechanism 40 and the lifting device 50 that constitute the processing unit. A column 19 erected at the rear of the base 10 is provided with the lifting device 50 that moves the grinding mechanism 40 up and down in the Z-axis direction.

[0020] The lifting device 50 includes a pair of guide rails 51 disposed on the front side of the column 19 and extending in the Z-axis direction, a lifting table 52 installed so as to be movable in the Z-axis direction relative to the pair of guide rails 51, and a ball screw 53 extending in the Z-axis direction and screwed into a screw-type portion (not shown) of the lifting table 52. The ball screw 53 is rotated by the driving force of a motor 54 connected to one end of the ball screw 53, thereby moving the lifting table 52 in the Z-axis direction.

[0021] The grinding mechanism 40 is attached to the front surface of the lift table 52 via a holder 41, and rotatably supports a spindle 43 with respect to a spindle housing 42 supported by the holder 41. The spindle 43 rotates around an axis in the Z-axis direction by the driving force of a spindle motor 44.

[0022] A mount 45 is connected to the lower end of the spindle 43, and a grinding wheel 46 is attached to the mount 45. A plurality of grinding wheels 47, which serve as processing tools, are provided in an annular shape on the underside of the grinding wheel 46. The grinding mechanism 40 grinds the upper surfaces of each of the plate-shaped workpieces W11 and W12 held on the chuck table 61 using the grinding wheels 47.

[0023] The grinding apparatus 1 further includes a holding device 60 for holding the plate-shaped workpieces W11 and W12. The holding device 60 includes a chuck table 61. The chuck table 61 includes a frame 62 and a disk-shaped porous member 64 attached to a recess 63 (see FIG. 2) on the upper surface of the frame 62. The porous member 64 is made of a porous material such as ceramics, and has fine pores formed throughout. With the porous member 64 attached to the recess 63, the upper surface of the frame 62 and the upper surface of the porous member 64 are flush with each other.

[0024] The chuck table 61 is provided with partitions 65 provided to radially divide the porous member 64. The partitions 65 are made of an air-impermeable material and are arranged concentrically around the center of the chuck table 61, dividing the porous member 64 like a Baumkuchen into a central region and an outer region surrounding the central region.

[0025] The upper surface, which is the exposed surface of the porous member 64, is made into a holding surface whose area can be changed according to the size of each plate-shaped workpiece W11, W12 to be held. Here, in this embodiment, the upper surface (exposed surface) of the porous member 64 inside the partition portion 65 is made into a first holding surface 67, and the upper surface (exposed surface) of the porous member 64 outside the first holding surface 67 and the partition portion 65 is made into a second holding surface 68. The holding surface of the chuck table 61 is formed by the first holding surface 67 and the second holding surface 68.

[0026] The first holding surface 67 has a diameter corresponding to the diameter of the plate-shaped workpiece W11 and serves as a holding surface when the chuck table 61 suction-holds the plate-shaped workpiece W11. The outer diameter of the upper surface of the second holding surface 68 corresponds to the diameter of the plate-shaped workpiece W12, and when the chuck table 61 suction-holds the plate-shaped workpiece W12, the first holding surface 67 and the second holding surface 68 serve as holding surfaces (see FIG. 3).

[0027] The grinding device 1 further includes a thickness measuring device 15 on the base 10. The thickness measuring device 15 includes a first height gauge that measures the height position of the upper surface of each of the plate-shaped workpieces W11, W12 held on the chuck table 61, and a second height gauge that measures the height position of the upper surface of the chuck table 61, and measures the thickness of each of the plate-shaped workpieces W11, W12 based on the difference between the measurement value of the first height gauge and the measurement value of the second height gauge.

[0028] Fig. 2 is an explanatory side view showing a state in which a first plate-shaped workpiece is held by the holding device. Fig. 3 is an explanatory side view showing a state in which a second plate-shaped workpiece is held by the holding device. As shown in Figs. 2 and 3, in addition to the above-mentioned chuck table 61, the holding device 60 is equipped with a suction source 70 constituted by a vacuum generating device such as a vacuum pump or an ejector, and an air supply source 71 and a water supply source 72 constitute fluid supply sources. The air supply source 71 supplies compressed air, and the water supply source 72 supplies water used for cleaning.

[0029] The holding device 60 also includes a porous member 64 that is disposed inside the partition 65 and forms a first holding surface 67, and a first branched communication passage 73 that connects the suction source 70, the air supply source 71, and the water supply source 72. The first branched communication passage 73 is composed of grooves and flow paths formed in the frame 62, and hoses, pipes, etc. that are connected to and branch off from the flow paths, etc. In the first branched communication passage 73, a first suction on-off valve 75 is provided between the branching position and the suction source 70, a first air supply on-off valve 76 is provided between the branching position and the air supply source 71, and a first water supply on-off valve 77 is provided between the branching position and the water supply source 72.

[0030] Furthermore, the holding device 60 further includes a porous member 64 disposed outside the partition 65 and forming a second holding surface 68, and a second branch communication passage 74 that connects the suction source 70, the air supply source 71, and the water supply source 72. The second branch communication passage 74 is also configured by grooves and flow paths formed in the frame 62, and hoses, pipes, etc. that are connected to the flow paths and branch in three directions. In the second branch communication passage 74, a second suction opening / closing valve 80 is provided between the branching position and the suction source 70, a second air supply opening / closing valve 81 is provided between the branching position and the air supply source 71, and a second water supply opening / closing valve 82 is provided between the branching position and the water supply source 72.

[0031] In addition, in the valves shown in Figures 2 and 3 and Figures 4 to 12 described below, the valves shown in black indicate an open state, and the valves shown in white indicate a closed state.

[0032] The holding device 60 is provided with a change mechanism 84 that changes the shape of the holding surface of the chuck table 61 by switching between suction and holding by only the first holding surface 67 and suction and holding by both the first holding surface 67 and the second holding surface 68. The change mechanism 84 is configured with the above-mentioned suction source 70, each of the branched communication passages 73, 74 that communicate with the suction source 70, and each of the suction open / close valves 75, 80 that switch between suction and suction stop by the suction source 70.

[0033] The holding device 60 also includes a fluid ejection mechanism 85 that switches between ejecting fluid only from the second holding surface 68, ejecting fluid from both the first holding surface 67 and the second holding surface 68, and stopping ejection of fluid from each of the holding surfaces 67, 68. Here, the fluid can be selected from air only, water only, or a mixture of air and water. The fluid ejection mechanism 85 includes the air supply source 71 and the water supply source 72 described above, and branched communication passages 73, 74 that communicate with the air supply source 71 and the water supply source 72. The fluid ejection mechanism 85 also includes air supply opening / closing valves 76, 81 and water supply opening / closing valves 77, 82 that switch between supplying and stopping the air and water from the air supply source 71 and the water supply source 72.

[0034] Furthermore, the holding device 60 is provided with a pressure gauge 87 serving as a determination mechanism between the branch position of the second branch communication passage 74 and the frame 62. The pressure gauge 87 measures the pressure value of fluids including air (gas), water (liquid), and mixed fluids inside the second branch communication passage 74. Based on the pressure value measured by the pressure gauge 87, it becomes possible to determine whether the plate-shaped workpiece W11 is held by the first holding surface 67 of the chuck table 61, or whether the plate-shaped workpiece W12 is held by both the first holding surface 67 and the second holding surface 68.

[0035] The operation of each part of the grinding apparatus 1 is controlled by a control unit 90 (see FIG. 1). The control unit 90 is configured with a processor that executes various processes and a storage unit (memory) that stores various parameters, programs, etc. The storage unit of the control unit 90 stores, as part of the control program, a program for controlling the operation of the grinding mechanism 40, the holding device 60, etc. For example, the control unit 90 controls the opening and closing of the opening and closing valves 75-77 and 80-82 based on the pressure value measured by the pressure gauge 87 in the holding device 60, and controls suction and fluid ejection at the first holding surface 67 and the second holding surface 68. Regarding the operation of each part of the grinding apparatus 1 described below, unless a control entity is specified, it is assumed that the operation is controlled by a control signal sent from the control unit 90.

[0036] Hereinafter, a grinding method (processing method) for a plate-shaped workpiece in this embodiment will be described with reference to Fig. 2 to Fig. 5. The grinding method for a plate-shaped workpiece in this embodiment is carried out in the order of a holding step, a determination step, and a grinding step (processing step). Figs. 2 and 3 are side views for explaining the holding step, Figs. 4 and 5 are side views for explaining the determination step, and Fig. 6 is a side view for explaining the grinding step.

[0037] [Holding process] 2 and 3, in the holding process, one of the two plate-shaped workpieces, the plate-shaped workpiece W11 and the plate-shaped workpiece W12, is selected and transported to and placed on the chuck table 61. In the state shown in FIG. 2, the first suction opening / closing valve 75 is opened to connect the suction source 70 to the first holding surface 67, and air is sucked from the first holding surface 67, creating a negative pressure, whereby the plate-shaped workpiece W11 is sucked and held on the first holding surface 67.

[0038] 3 shows a state in which the plate-shaped workpiece W12 is held on the chuck table 61. In this state, both suction on-off valves 75, 80 are open, and the suction source 70 is connected to both the first holding surface 67 and the second holding surface 68. As a result, air is sucked from both the first holding surface 67 and the second holding surface 68, creating a negative pressure, and the plate-shaped workpiece W12 is held by suction on both the first holding surface 67 and the second holding surface 68.

[0039] During the holding step, the air supply opening / closing valves 76 and 81 and the water supply opening / closing valves 77 and 82 are closed.

[0040] [Judgment process] A determination step is carried out after the holding step and before the grinding step. In the determination step, from the state shown in Fig. 2, the second air supply on-off valve 81 and the second water supply on-off valve 82 are opened to connect the second holding surface 68 to the air supply source 71 and the water supply source 72, as shown in Fig. 4. At this time, the pressure value applied to the second holding surface 68 is measured by the pressure gauge 87, and the measured pressure value is output to the control unit 90. Note that the pressure value measured by the pressure gauge 87 is relatively considerably smaller when the plate-shaped workpiece W11 is held and the second holding surface 68 is exposed than when the plate-shaped workpiece W12 is held and the second holding surface 68 is covered, as shown in Fig. 3.

[0041] The control unit 90 inputs the pressure value measured by the pressure gauge 87 and compares it with, for example, a predetermined threshold value stored in advance. If the pressure value of the pressure gauge 87 is smaller than the threshold value, the second holding surface 68 is in an exposed state, and the control unit 90 determines that a plate-shaped workpiece W11 is being held on the chuck table 61. On the other hand, if the pressure value of the pressure gauge 87 is larger than the threshold value, the second holding surface 68 is in a covered state, and the control unit 90 determines that a plate-shaped workpiece W12 is being held on the chuck table 61.

[0042] In the determination step, the fluid measured by the pressure gauge 87 may be changed as shown in Fig. 5. In Fig. 5, from the state shown in Fig. 2, the second suction on-off valve 80 is opened to connect the second holding surface 68 to the suction source 70. At this time, the pressure value applied to the second holding surface 68 is measured by the pressure gauge 87, and the measured pressure value is output to the control unit 90 as a negative pressure value because the second holding surface 68 is connected to the suction source 70. The pressure value measured by the pressure gauge 87 is relatively significantly larger (the negative pressure value is smaller) when the second holding surface 68 is exposed while holding the plate-shaped workpiece W11 compared to when the second holding surface 68 is covered while holding the plate-shaped workpiece W12 as shown in Fig. 3.

[0043] The control unit 90 inputs the pressure value measured by the pressure gauge 87 and compares it with a predetermined threshold value stored in advance. If the pressure value of the pressure gauge 87 is greater than the threshold value (the negative pressure value is small), the second holding surface 68 is in an exposed state, and the control unit 90 determines that a plate-shaped workpiece W11 is being held on the chuck table 61. On the other hand, if the pressure value of the pressure gauge 87 is smaller than the threshold value (the negative pressure value is large), the second holding surface 68 is in a covered state, and the control unit 90 determines that a plate-shaped workpiece W12 is being held on the chuck table 61.

[0044] [Grinding process] After the holding step and the determining step, the grinding step is carried out. In the grinding step, the plate-shaped workpiece W11 is ground by the grinding mechanism 40 while maintaining the open / closed states of the on-off valves 75 to 77, 80 to 82 in the holding device 60 from the state shown in Fig. 4 to that shown in Fig. 6.

[0045] Specifically, in the holding device 60, by opening the first suction on-off valve 75 and closing the second suction on-off valve 80, the suction source 70 and the first holding surface 67 are connected to each other, and the plate-shaped workpiece W11 is held by suction, and communication between the suction source 70 and the second holding surface 68 is blocked. In addition, by opening the second air supply on-off valve 81 and the second water supply on-off valve 82, the second holding surface 68 is connected to the air supply source 71 and the water supply source 72, and a mixed fluid of water and air is ejected from the second holding surface 68. Therefore, the mixed fluid is ejected from the second holding surface 68, which is the portion of the holding surface of the chuck table 61 that is exposed to the outside of the held plate-shaped workpiece W11.

[0046] The chuck table 61 is positioned below the grinding wheel 46 in the grinding mechanism 40, and the table rotation mechanism 30 rotates the chuck table 61 and the plate-shaped workpiece W11 held by suction. The elevating device 50 (see FIG. 1) lowers the grinding mechanism 40 while rotating the grinding wheel 47 via the spindle 43. In this way, the grinding wheel 47 and the plate-shaped workpiece W11 held by suction on the chuck table 61 are brought into contact with each other while rotating, thereby grinding the top surface of the plate-shaped workpiece W11. During this grinding process, the mixed fluid is sprayed from the second holding surface 68, preventing grinding chips (machining chips) from adhering to the exposed second holding surface 68.

[0047] When the plate-shaped workpiece W12 is held on the chuck table 61, it is ground by the grinding mechanism 40 in the same manner as described above, and both the first holding surface 67 and the second holding surface 68 are covered during grinding (see FIG. 3). Therefore, grinding debris does not adhere to the second holding surface 68 during grinding, so the second air supply opening / closing valve 81 and the second water supply opening / closing valve 82 are closed, and the spraying of the mixed fluid by the air supply source 71 and the water supply source 72 is stopped.

[0048] According to the first embodiment, in the grinding process for grinding the plate-shaped workpiece W11, the plate-shaped workpiece W11 can be ground while the fluid mixture is ejected from the exposed second holding surface 68. This makes it possible to prevent grinding chips from adhering to the second holding surface 68 located on the outer side of the plate-shaped workpiece W11. Therefore, when the plate-shaped workpiece W12 is held and ground by the first holding surface 67 and the second holding surface 68, it is possible to prevent grinding chips from getting between the second holding surface 68 and the plate-shaped workpiece W12, and it is possible to grind the plate-shaped workpiece W12 to a uniform thickness and maintain good processing accuracy.

[0049] Furthermore, by performing the determination step, the control unit 90 can determine, before the grinding step, whether the second holding surface 68 is exposed to the outside of the plate-shaped workpiece (plate-shaped workpiece W11) held by the holding surface of the chuck table 61. This increases the reliability of ejecting fluid from the second holding surface 68, making it possible to better prevent grinding chips from adhering to the second holding surface 68.

[0050] Next, other embodiments of the present invention will be described. In the following description, the same reference numerals may be used to designate components that are the same as or equivalent to those in the embodiments described before the embodiment, and the description thereof may be omitted or simplified.

[0051] [Second embodiment] A second embodiment of the present invention will be described with reference to Figs. 7 to 9. Fig. 7 is an explanatory partial plan view of a holding device in the second embodiment. Fig. 8 is an explanatory partial plan view showing an example of a grinding method in the second embodiment. Fig. 9 is an explanatory partial plan view showing another example of a grinding method in the second embodiment. Figs. 7 to 9 illustrate a part of a holding device 60 in the second embodiment, and in the chuck table 61, the porous member 100 and the partition portion 101 are illustrated, but the frame is not illustrated.

[0052] The chuck table 61 of the second embodiment is configured to be able to selectively hold a circular workpiece W21 (see FIG. 8) that will be the first plate-shaped workpiece, or a rectangular workpiece W22 (see FIG. 9) that will be the second plate-shaped workpiece. Therefore, during grinding, one of the circular workpiece W21 and the rectangular workpiece W22 is held on the chuck table 61. The rectangular workpiece W22 is formed so that its vertical width in FIGS. 8 and 9 is smaller than the diameter of the circular workpiece W21 and its horizontal width is larger than the diameter of the circular workpiece W21.

[0053] The holding surface formed on the upper surface of the porous member 100 by the chuck table 61 is formed in a shape in which a circle corresponding to the circular workpiece W21 and a rectangle corresponding to the rectangular workpiece W22 are overlapped so that their centers coincide with each other. Partitions 101 are formed in the part where the outline of the circle overlaps with the rectangle and in the part where the outline of the rectangle overlaps with the circle.

[0054] The porous member 100 is divided into five regions by partitions 101, and in FIG. 7, the regions are shown with patterns for ease of visualization. The porous member 100 forms a common holding surface 102 in the region with a checkered pattern in FIG. 7. The porous member 100 also forms a pair of first workpiece holding surfaces 103 in regions with diagonal lines slanting upward to the right on both the top and bottom in FIG. 7, which are outside the common holding surface 102. Furthermore, the porous member 100 forms a pair of second workpiece holding surfaces 104 in regions with diagonal lines slanting downward to the right on both the left and right in FIG. 7, which are outside the common holding surface 102.

[0055] The holding device 60 of the second embodiment includes, in addition to the chuck table 61, a suction source 70, a fluid supply source 106, a first branched communicating passage 107, a second branched communicating passage 108, and a third branched communicating passage 109. The fluid supply source 106 supplies at least one of air alone, water alone, or a mixture of air and water, which are the fluids supplied by the air supply source 71 and the water supply source 72 in the first embodiment.

[0056] The first branched communicating passage 107 communicates the area forming the common holding surface 102 of the porous member 100 with the suction source 70 and the fluid supply source 106. The first branched communicating passage 107 branches to communicate with the suction source 70 and the fluid supply source 106, and is provided with a first suction on-off valve 111 between the branched position and the suction source 70, and a first fluid supply on-off valve 112 between the branched position and the fluid supply source 106. The first branched communicating passage 107 is also provided with a first pressure gauge (determination mechanism) 113 that measures the pressure value of the fluid inside.

[0057] The second branch communication passage 108 communicates between the region of the porous member 100 that forms the pair of first workpiece holding surfaces 103 and the suction source 70 and fluid supply source 106. The second branch communication passage 108 branches to communicate with the suction source 70 and fluid supply source 106, and a second suction on-off valve 115 is provided between the branching position and the suction source 70, and a second fluid supply on-off valve 116 is provided between the branching position and the fluid supply source 106. The second branch communication passage 108 also branches on the chuck table 61 side to communicate with each of the pair of first workpiece holding surfaces 103. In addition, the second branch communication passage 108 is provided with a second pressure gauge (determination mechanism) 117 that measures the pressure value of the fluid inside.

[0058] The third branch communication passage 109 communicates between the region of the porous member 100 that forms the pair of second workpiece holding surfaces 104 and the suction source 70 and fluid supply source 106. The third branch communication passage 109 branches to communicate with the suction source 70 and fluid supply source 106, and a third suction on-off valve 119 is provided between the branching position and the suction source 70, and a third fluid supply on-off valve 120 is provided between the branching position and the fluid supply source 106. The third branch communication passage 109 also branches on the chuck table 61 side to communicate with each of the pair of second workpiece holding surfaces 104. In addition, the third branch communication passage 109 is provided with a third pressure gauge (determination mechanism) 121 that measures the pressure value of the fluid inside.

[0059] Next, a description will be given of a method for grinding a plate-shaped workpiece according to the second embodiment. In this grinding method, the holding step, the determining step, and the grinding step (processing step) are also carried out in this order.

[0060] [Holding process] When the circular workpiece W21 is held on the chuck table 61 in the holding process, the circular workpiece W21 is arranged so as to overlap the common holding surface 102 and the pair of first workpiece holding surfaces 103, as shown in Fig. 8. In this state, by opening the first suction on-off valve 111 and the second suction on-off valve 115, the suction source 70 is connected to the common holding surface 102 and the first workpiece holding surface 103. As a result, air is sucked from the common holding surface 102 and the first workpiece holding surface 103, creating a negative pressure, and the circular workpiece W21 is suction-held by the common holding surface 102 and the first workpiece holding surface 103. At this time, the first workpiece holding surface 103 holds the circular workpiece W21 outside the common holding surface 102.

[0061] 9 shows a state in which the rectangular workpiece W22 is held by the chuck table 61. In this state, by opening the first suction on-off valve 111 and the third suction on-off valve 119, the suction source 70 is connected to the common holding surface 102 and the second workpiece holding surface 104. As a result, air is sucked from the common holding surface 102 and the second workpiece holding surface 104, causing a negative pressure to act, and the rectangular workpiece W22 is suction-held by the common holding surface 102 and the second workpiece holding surface 104. At this time, the second workpiece holding surface 104 holds the rectangular workpiece W22 outside the common holding surface 102.

[0062] [Judgment process] In the state shown in Fig. 8, the determination step after the holding step opens the third fluid supply on-off valve 120 to connect the second work holding surface 104 to the fluid supply source 106. At this time, the pressure value applied to the second work holding surface 104 is measured by the third pressure gauge 121, and the measured pressure value is output to the control unit 90 (see Fig. 1). Note that the pressure value measured by the third pressure gauge 121 is relatively much smaller when the second work holding surface 104 is exposed because a circular work W21 is held than when the second work holding surface 104 is covered because a rectangular work W22 is held, as shown in Fig. 9.

[0063] The control unit 90 inputs the pressure value measured by the third pressure gauge 121 and compares it with, for example, a predetermined threshold value stored in advance. If the pressure value of the third pressure gauge 121 is smaller than the threshold value, the second workpiece holding surface 104 is exposed, and the control unit 90 determines that a circular workpiece W21 is held on the chuck table 61 (see FIG. 8). On the other hand, if the pressure value of the third pressure gauge 121 is larger than the threshold value, the second workpiece holding surface 104 is covered, and the control unit 90 determines that a rectangular workpiece W22 is held on the chuck table 61 (see FIG. 9).

[0064] Here, in the determination step of the second embodiment, the fluid measured by the third pressure gauge 121 may be changed. In this case, from the state shown in FIG. 8 , the third fluid supply on-off valve 120 is closed and the third suction on-off valve 119 is opened to connect the second workpiece holding surface 104 to the suction source 70. At this time, the third pressure gauge 121 measures the pressure value applied to the second workpiece holding surface 104, and the measured pressure value is output to the control unit 90 as a negative pressure value because the second workpiece holding surface 104 is connected to the suction source 70. The pressure value measured by the third pressure gauge 121 is relatively significantly larger (the negative pressure value is smaller) when the second workpiece holding surface 104 is exposed by holding a circular workpiece W21 than when the second workpiece holding surface 104 is covered by holding a rectangular workpiece W22 as shown in FIG. 9 .

[0065] The control unit 90 inputs the pressure value measured by the third pressure gauge 121 and compares it with a predetermined threshold value stored in advance. If the pressure value of the third pressure gauge 121 is greater than the threshold value (the negative pressure value is small), the second workpiece holding surface 104 is exposed, and the control unit 90 determines that a circular workpiece W21 is held on the chuck table 61 (see FIG. 8). On the other hand, if the pressure value of the third pressure gauge 121 is smaller than the threshold value (the negative pressure value is large), the second workpiece holding surface 104 is covered, and the control unit 90 determines that a rectangular workpiece W22 is held on the chuck table 61 (see FIG. 9).

[0066] In the above-described judgment process, the pressure value was measured using the third pressure gauge 121 to determine whether a circular workpiece W21 or a rectangular workpiece W22 was being held on the chuck table 61, but the same judgment can be made by measuring the pressure value using the second pressure gauge 117 instead.

[0067] For example, from the state shown in Fig. 8, the third fluid supply open / close valve 120 is closed and the second fluid supply open / close valve 116 is opened, thereby connecting the first workpiece holding surface 103 to the fluid supply source 106. At this time, the pressure value applied to the first workpiece holding surface 103 is measured by the second pressure gauge 117, and the measured pressure value is output to the control unit 90. Note that the pressure value measured by the second pressure gauge 117 is relatively significantly larger when the first workpiece holding surface 103 is covered by holding a circular workpiece W21 than when the first workpiece holding surface 103 is exposed by holding a rectangular workpiece W22 as shown in Fig. 9.

[0068] The control unit 90 inputs the pressure value measured by the second pressure gauge 117 and compares it with, for example, a predetermined threshold value stored in advance. If the pressure value of the second pressure gauge 117 is greater than the threshold value, the first workpiece holding surface 103 is covered, and the control unit 90 determines that a circular workpiece W21 is held on the chuck table 61 (see FIG. 8). On the other hand, if the pressure value of the second pressure gauge 117 is less than the threshold value, the first workpiece holding surface 103 is exposed, and the control unit 90 determines that a rectangular workpiece W22 is held on the chuck table 61 (see FIG. 9).

[0069] As another example, the fluid measured by the second pressure gauge 117 is changed, the third fluid supply on-off valve 120 is closed from the state shown in Fig. 8, and the second suction on-off valve 115 is left open, maintaining the state in which the first work holding surface 103 is connected to the suction source 70. The pressure value applied to the first work holding surface 103 is measured by the second pressure gauge 117, and the measured pressure value is output to the control unit 90 as a negative pressure value because the first work holding surface 103 is connected to the suction source 70. The pressure value measured by the second pressure gauge 117 is relatively significantly smaller (the negative pressure value is larger) when the first work holding surface 103 is covered by holding a circular workpiece W21 compared to when the first work holding surface 103 is exposed by holding a rectangular workpiece W22 as shown in Fig. 9.

[0070] The control unit 90 inputs the pressure value measured by the second pressure gauge 117 and compares it with a predetermined threshold value stored in advance. If the pressure value of the second pressure gauge 117 is smaller than the threshold value (the negative pressure value is large), the first workpiece holding surface 103 is covered, and the control unit 90 determines that a circular workpiece W21 is held on the chuck table 61 (see FIG. 8). On the other hand, if the pressure value of the second pressure gauge 117 is larger than the threshold value (the negative pressure value is small), the first workpiece holding surface 103 is exposed, and the control unit 90 determines that a rectangular workpiece W22 is held on the chuck table 61 (see FIG. 9).

[0071] [Grinding process] In the determination step, it is determined that the circular workpiece W21 is being held, and when the circular workpiece W21 is held as shown in Fig. 8, in the grinding step, the third fluid supply on-off valve 120 is opened to connect the second workpiece holding surface 104 to the fluid supply source 106. As a result, the fluid supplied from the fluid supply source 106 is sprayed from the second workpiece holding surface 104, and the fluid is sprayed from the second workpiece holding surface 104, which is the portion of the holding surface of the chuck table 61 that is exposed to the outside of the held circular workpiece W21.

[0072] While the fluid is being ejected from the second workpiece holding surface 104 in this manner, the circular workpiece W21 is ground by the grinding mechanism 40 in the same manner as in the first embodiment.

[0073] Furthermore, when it is determined in the determination step that the rectangular workpiece W22 is being held, and the rectangular workpiece W22 is held as shown in Fig. 9, in the grinding step, the second fluid supply open / close valve 116 is opened to connect the first workpiece holding surface 103 to the fluid supply source 106. As a result, the fluid supplied from the fluid supply source 106 is sprayed from the first workpiece holding surface 103, and the fluid is sprayed from the first workpiece holding surface 103, which is the portion of the holding surface of the chuck table 61 that is exposed to the outside of the held rectangular workpiece W22.

[0074] While the fluid is being ejected from the first workpiece holding surface 103 in this manner, the rectangular workpiece W22 is ground by the grinding mechanism 40 in the same manner as in the first embodiment.

[0075] As described above, according to the second embodiment, in the grinding process of the circular workpiece W21, the fluid can be ejected from the second workpiece holding surface 104 exposed to the outside of the circular workpiece W21, and in the grinding process of the rectangular workpiece W22, the fluid can be ejected from the first workpiece holding surface 103 exposed to the outside of the rectangular workpiece W22. This makes it possible to prevent grinding chips from adhering regardless of whether the first workpiece holding surface 103 or the second workpiece holding surface 104 is exposed in the grinding process. Therefore, whether the circular workpiece W21 or the rectangular workpiece W22 is being ground, it is possible to prevent grinding chips from being interposed and grind the workpiece to a uniform thickness.

[0076] [Third embodiment] A third embodiment of the present invention will be described with reference to Figs. 10 to 12. Fig. 10 is a partial plan view for explaining a holding device in the third embodiment. Fig. 11 is a partial plan view for explaining an example of a grinding method in the third embodiment. Fig. 12 is a partial plan view for explaining another example of a grinding method in the third embodiment. Figs. 10 to 12 illustrate a part of a holding device 60 in the third embodiment, and similarly to Figs. 7 to 9, the porous member 100 and the partition portion 101 are illustrated in the chuck table 61, but the frame is not illustrated.

[0077] The third embodiment differs from the second embodiment in that the configurations of the chuck table 61, the first branched communication passage 107, and the second branched communication passage 108 are changed, but the rest of the configuration is the same as that of the second embodiment.

[0078] The chuck table 61 of the third embodiment is configured to be able to selectively hold a circular workpiece W31 (see FIG. 11) which is one first plate-shaped workpiece, and a rectangular workpiece W32 (see FIG. 12) which is two second plate-shaped workpieces. Therefore, during grinding, one of the one circular workpiece W31 and the two rectangular workpieces W32 is held on the chuck table 61. The rectangular workpiece W32 is formed so that the vertical width in FIGS. 11 and 12 is smaller than the radius of the circular workpiece W31 and the horizontal width is larger than the diameter of the circular workpiece W31.

[0079] The holding surface formed on the upper surface of the porous member 100 by the chuck table 61 is formed in a shape in which a circular portion corresponding to one circular workpiece W31 and two rectangular portions corresponding to two rectangular workpieces W32 are overlapped. One of the two rectangular portions is disposed so as to extend slightly upward from the upper portion of the circular portion in FIG. 10, and the other of the two rectangular portions is disposed so as to extend slightly downward from the lower portion of the circular portion in FIG. 10. Partition portions 101 are formed at the portion where the outline of the circular portion overlaps with the two rectangular portions and at the portion where the outlines of the two rectangular portions overlap with the circular portions.

[0080] The porous member 100 is divided into five regions by partitions 101, and in FIG. 10, the regions are conveniently shown with patterns to facilitate visualization. The porous member 100 forms a pair of common holding surfaces 102 in the regions with a checkered pattern in FIG. 10. The porous member 100 also forms a first workpiece holding surface 103 in a region with a diagonal line pattern slanting upward to the right that is sandwiched between the pair of common holding surfaces 102 and outside the pair of common holding surfaces 102. Furthermore, the porous member 100 forms a pair of second workpiece holding surfaces 104 in a region with a diagonal line pattern slanting downward to the right on both the left and right sides in FIG. 10, which are outside the pair of common holding surfaces 102, and on the opposite side of the first workpiece holding surface 103.

[0081] The first branched communication passage 107 in the third embodiment also branches on the chuck table 61 side so as to communicate with each of the pair of common holding surfaces 102. In addition, the second branched communication passage 108 communicates with one first workpiece holding surface 103, and is configured not to branch on the chuck table 61 side.

[0082] The grinding method of the third embodiment differs from the second embodiment in that one circular workpiece W31 (see FIG. 11) and two rectangular workpieces W32 (see FIG. 12) are selected and held. In other respects, the grinding method can be carried out in the same manner in the second and third embodiments. Therefore, as in the third embodiment, two rectangular workpieces W32 can be held, and fluid can be ejected from the first workpiece holding surface 103 and the second workpiece holding surface 104 that are exposed during the grinding process to prevent grinding chips from adhering.

[0083] The present invention is not limited to the above-described embodiments, and various modifications can be made to the embodiments. In the above-described embodiments, the size and shape shown in the accompanying drawings are not limited to these, and can be modified as appropriate within the scope of the effects of the present invention. In addition, the present invention can be modified as appropriate without departing from the scope of the object of the present invention.

[0084] The shapes and sizes of the plate-shaped workpieces held and machined in the above-described embodiments are merely examples, and various modifications are possible, such as polygons other than circles and rectangles, shapes with curved sides, etc. Furthermore, the shapes and sizes of the plate-shaped workpieces held and machined by the chuck table 61 only need to be selectable from at least two types, and may be three or more different shapes.

[0085] In addition, the fluid to be sprayed in the grinding method of the first embodiment may be a mixed fluid, or only air may be sprayed by opening the second air supply opening / closing valve 81 and closing the second water supply opening / closing valve 82, or only water may be sprayed by closing the second air supply opening / closing valve 81 and opening the second water supply opening / closing valve 82.

[0086] In addition, in the above embodiments, grinding has been described as an example of the processing step, but other processing steps such as polishing, cutting, etc. may also be performed. When polishing is performed, the processing tool is a polishing pad, and when cutting is performed, the processing tool is a cutting tool or a cutting blade. [Industrial Applicability]

[0087] As described above, the present invention has the effect of preventing machining chips from adhering to the exposed holding surface and becoming trapped between the plate-shaped workpiece and the holding surface when selectively holding and processing plate-shaped workpieces of different shapes. [Explanation of symbols]

[0088] 1: Grinding equipment (processing equipment) 40: Grinding mechanism (processing unit) 47: Grinding wheel (processing tool) 61: Chuck table (universal chuck table) 67: 1st holding surface (holding surface) 68:Second holding surface (holding surface) 70: Suction source 71: Air supply source (fluid supply source) 72: Water supply source (fluid supply source) 84: Change mechanism 85:Fluid ejection mechanism 87: Pressure gauge (judgment mechanism) 102: Common holding surface (holding surface) 103: First workpiece holding surface (holding surface) 104: Second work holding surface (holding surface) 106 :Fluid supply source 113: First pressure gauge (judgment mechanism) 117: Second pressure gauge (judgment mechanism) 121: Third pressure gauge (judgment mechanism) W11: Plate-shaped workpiece (first plate-shaped workpiece) W12: Plate-shaped workpiece (second plate-shaped workpiece) W21: Circular workpiece (first plate-shaped workpiece, plate-shaped workpiece) W22: Rectangular workpiece (second plate-shaped workpiece, plate-shaped workpiece) W31: Circular workpiece (first plate-shaped workpiece, plate-shaped workpiece) W32: Rectangular workpiece (second plate-shaped workpiece, plate-shaped workpiece)

Claims

1. A method for machining a plate-shaped workpiece, comprising holding one of at least two plate-shaped workpieces, a first plate-shaped workpiece and a second plate-shaped workpiece having a shape different from that of the first plate-shaped workpiece, on a universal chuck table, and machining the plate-shaped workpiece with a machining tool, the universal chuck table includes a first holding surface for suction-holding the first plate-shaped workpiece, and a second holding surface on the outer side of the first holding surface for suction-holding the second plate-shaped workpiece; a holding step of suction-holding the first plate-shaped workpiece on the first holding surface; The method for machining a plate-shaped workpiece comprises, after the holding step, a machining step of machining the first plate-shaped workpiece while ejecting a fluid from the second holding surface.

2. A method for machining a plate-shaped workpiece as described in claim 1, which includes a determination step, after the holding step and before the machining step, of determining whether the plate-shaped workpiece is the first plate-shaped workpiece or the second plate-shaped workpiece based on the pressure value applied to the second holding surface by connecting the second holding surface to a suction source, or the pressure value applied to the second holding surface by connecting the second holding surface to a fluid supply source.

3. A method for machining a plate-shaped workpiece, comprising holding one of at least two plate-shaped workpieces, a first plate-shaped workpiece and a second plate-shaped workpiece having a shape different from that of the first plate-shaped workpiece, on a universal chuck table and machining the plate-shaped workpiece, The universal chuck table is a common holding surface that can suck the first plate-shaped workpiece and the second plate-shaped workpiece; a first workpiece holding surface that holds the first plate-shaped workpiece outside the common holding surface; a second workpiece holding surface that holds the second plate-shaped workpiece outside the common holding surface, a holding step of holding the first plate-shaped workpiece between the common holding surface and the first workpiece holding surface, or holding the second plate-shaped workpiece between the common holding surface and the second workpiece holding surface; When the first plate-shaped workpiece is held in the holding step, the first plate-shaped workpiece is machined while a fluid is ejected from the second workpiece holding surface; A method for machining a plate-shaped workpiece, comprising: a machining step of machining the second plate-shaped workpiece while spraying a fluid from the first workpiece holding surface when the second plate-shaped workpiece is held in the holding step.

4. A method for machining a plate-shaped workpiece, comprising holding one of at least two plate-shaped workpieces, a first plate-shaped workpiece and a second plate-shaped workpiece having a shape different from that of the first plate-shaped workpiece, on a universal chuck table, and machining the plate-shaped workpiece with a machining tool, The universal chuck table is a common holding surface that can suck the first plate-shaped workpiece and the second plate-shaped workpiece; a first workpiece holding surface that holds the first plate-shaped workpiece outside the common holding surface; a second workpiece holding surface that holds the second plate-shaped workpiece outside the common holding surface, a holding step of suction-holding the first plate-shaped workpiece or the second plate-shaped workpiece on the common holding surface; a determining step after the holding step of determining whether the plate-shaped workpiece is the first plate-shaped workpiece or the second plate-shaped workpiece based on the pressure value applied to the first workpiece holding surface or the second workpiece holding surface by connecting the first workpiece holding surface or the second workpiece holding surface to a suction source, or based on the pressure value applied to the first workpiece holding surface or the second workpiece holding surface by connecting the first workpiece holding surface or the second workpiece holding surface to a fluid supply source; If the plate-shaped workpiece is determined to be the first plate-shaped workpiece in the determination step, the first plate-shaped workpiece is machined while a fluid is ejected from the second workpiece holding surface; a machining step of machining the second plate-shaped workpiece while spraying fluid from the first workpiece holding surface if the determination step determines that the plate-shaped workpiece is the second plate-shaped workpiece.

5. A processing apparatus for carrying out the plate-shaped workpiece processing method according to any one of claims 1 to 4, a universal chuck table that holds, by a holding surface, one of at least two plate-shaped workpieces, the first plate-shaped workpiece and the second plate-shaped workpiece having a shape different from that of the first plate-shaped workpiece; a machining unit that machines a plate-shaped workpiece held on the universal chuck table; a change mechanism capable of changing the shape of the holding surface; A processing apparatus comprising: a fluid ejection mechanism that ejects a fluid from a portion of the holding surface that is exposed to the outside of the first plate-shaped workpiece or the second plate-shaped workpiece held on the universal chuck table.

6. 6. The processing apparatus according to claim 5, further comprising a determining mechanism for determining whether the plate-shaped workpiece held on the holding surface is the first plate-shaped workpiece or the second plate-shaped workpiece.

Images