Processing equipment

Abstract

To provide a processing device comprising a conveying unit capable of making a sufficient negative pressure act in accordance with a thickness of a work piece with a non-contact type suction holding device.SOLUTION: A processing device 1 comprises: a conveyance unit 60 that conveys a work piece 100 between a cassette 45 mounted on a cassette mounting part 40 and a chuck table 10; and a measurement unit 85 that measures a thickness of the work piece 100. The conveyance unit 60 comprises: a base part 61 providing a non-contact type suction holding device that generates a negative pressure by spraying an air, and sucks the work piece 100; and a movement unit 62 that moves the base part 61. The height of the non-contact type suction holding device is adjusted so as to be matched to the thickness of the work piece 100 measured by the measurement unit 85, and is arranged to a position at which an interval between the non-contact type suction holding device and a front surface 101 of the work piece 100 becomes a predetermined range to convey the work piece 100.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a processing apparatus equipped with a transport unit. [Background technology]

[0002] There is known an apparatus that processes plate-shaped workpieces such as wafers on which semiconductor devices or LEDs (Light Emitting Diodes) are formed, resin package substrates, glass substrates, etc., using a cutting blade or laser beam (see, for example, Patent Document 1). The workpieces are placed in the apparatus while contained in a cassette, transported to a chuck table by an internal transport unit, and once processed, are returned from the chuck table to the cassette after being cleaned by a cleaning device (or cleaning unit). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5846734 Summary of the Invention [Problem to be solved by the invention]

[0004] There are various types of conveying units, and one of them is a conveying method using a non-contact suction holder that generates negative pressure by injecting air onto the workpiece, as shown in Patent Document 1. If the distance between the air injection surface (end surface) of the non-contact suction holder and the workpiece is too far, negative pressure cannot be applied to the workpiece. For example, if the thickness of the workpiece is different, such as 3.0 mm or 0.5 mm, and the non-contact suction holder is always set to suck up a workpiece with a thickness of 3.0 mm, there is a risk that sufficient negative pressure cannot be applied to a 0.5 mm workpiece, and there is a problem that the workpiece cannot be transported.

[0005] The present invention has been made in consideration of such problems, and its object is to provide a processing apparatus equipped with a conveying unit that can apply sufficient negative pressure using a non-contact suction holder according to the thickness of the workpiece. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, the processing apparatus of the present invention is a processing apparatus comprising a chuck table which holds a plate-shaped workpiece, a processing unit which processes the workpiece held on the chuck table, a cassette mounting section on which a cassette containing the workpiece is mounted, a transport unit which transports the workpiece between the cassette mounted on the cassette mounting section and the chuck table, and a measurement unit which measures the thickness of the workpiece, wherein the transport unit comprises a base section which has a non-contact suction holder which injects air to generate negative pressure and sucks the workpiece in a non-contact state, and a moving unit which moves the base section, The measurement unit is a back pressure sensor or an optical sensor, and measures the thickness of the workpiece in a non-contact manner. The height of the non-contact suction holder is adjusted according to the thickness of the workpiece measured by the measurement unit, and the workpiece is transported while being positioned so that the distance between the non-contact suction holder and the surface of the workpiece is within a specified range. Effect of the Invention

[0008] The present invention is capable of applying a sufficient negative pressure to a workpiece using a non-contact suction holder in accordance with the thickness of the workpiece. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view showing a configuration example of a processing device according to the first embodiment. [Diagram 2] FIG. 2 is a perspective view showing a configuration example of a transport unit of the processing apparatus of FIG. [Diagram 3] FIG. 3 is a cross-sectional view illustrating the operation of the transport unit of the processing apparatus of FIG. [Figure 4] FIG. 4 is a cross-sectional view illustrating the operation of the transport unit of the processing apparatus of FIG. [Diagram 5]FIG. 5 is a diagram showing an example of the configuration of a measurement unit of the processing apparatus of FIG. [Figure 6] FIG. 6 is a cross-sectional view illustrating the operation of the measuring unit of the processing apparatus of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The form (embodiment) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiment. Furthermore, the components described below include those that a person skilled in the art can easily imagine and those that are substantially the same. Furthermore, the configurations described below can be appropriately combined. Furthermore, various omissions, substitutions, or modifications of the configurations can be made without departing from the gist of the present invention.

[0011] [Embodiment 1] A processing apparatus 1 according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a configuration example of the processing apparatus 1 according to the first embodiment. FIG. 2 is a perspective view showing a configuration example of the transport unit 60 of the processing apparatus 1 of FIG. 1. FIGS. 3 and 4 are cross-sectional views explaining the operation of the transport unit 60 of the processing apparatus 1 of FIG. 1. FIG. 5 is a diagram showing a configuration example of the measurement unit 85 of the processing apparatus 1 of FIG. 1. FIG. 6 is a cross-sectional view explaining the operation of the measurement unit 85 of the processing apparatus 1 of FIG. 1. As shown in FIG. 1, the processing apparatus 1 includes a chuck table 10, a processing unit 20, a cassette placement section 40, a carry-in / out unit 50, a cleaning device 55, a transport unit 60, a measurement unit 85, and a control unit 98.

[0012] The workpiece 100 to be processed by the processing apparatus 1 according to the first embodiment is, for example, a disk-shaped semiconductor wafer or an optical device wafer made of silicon, sapphire, silicon carbide (SiC), gallium arsenide, or the like. As shown in FIG. 1, the workpiece 100 has a flat surface 101 on which devices 103 are formed in areas partitioned by a plurality of planned division lines 102 formed in a lattice pattern. In the present invention, the workpiece 100 may be a rectangular package substrate having a plurality of devices sealed with resin, a ceramic plate, a glass plate, or the like. In the present invention, the workpiece 100 may also be a laminated plate-like object obtained by stacking or bonding a plurality of plate-like objects such as wafers in the thickness direction.

[0013] The chuck table 10 has a disk-shaped frame body with a recess formed therein and a disk-shaped suction part fitted in the recess. The suction part of the chuck table 10 is made of porous ceramics or the like and is connected to a vacuum suction source (not shown) via a vacuum suction path (not shown). The upper surface of the suction part of the chuck table 10 is a holding surface 11 on which the workpiece 100 is placed and which suction-holds the placed workpiece 100. The holding surface 11 and the upper surface of the frame body of the chuck table 10 are arranged on the same plane and are formed parallel to the XY plane, which is a horizontal plane. The chuck table 10 is movable in the X-axis direction, which is one horizontal direction, by an X-axis moving unit (not shown) and is rotatable around an axis parallel to the Z-axis direction, which is a vertical direction and perpendicular to the holding surface 11, by a rotary drive source (not shown).

[0014] As shown in Fig. 1, the processing unit 20 has a cutting blade 21 and a spindle 22. The cutting blade 21 is an extremely thin cutting grindstone having a substantially ring shape. The cutting blade 21 is rotated by the spindle 22 about an axis parallel to a Y-axis direction that is another horizontal direction and perpendicular to the X-axis direction, to cut the workpiece 100 held on the chuck table 10. The processing unit 20 is provided so as to be movable in the Y-axis direction by a Y-axis moving unit 32 with respect to the workpiece 100 held on the chuck table 10, and is also provided so as to be movable in the Z-axis direction by a Z-axis moving unit 33.

[0015] The processing device 1 includes at least an X-axis moving unit (not shown) for moving the chuck table 10 in the X-axis direction, a Y-axis moving unit 32 for indexing and feeding the processing unit 20 in the Y-axis direction, and a Z-axis moving unit 33 for cutting and feeding the processing unit 20 in the Z-axis direction, as shown in FIG. 1. The X-axis moving unit, the Y-axis moving unit 32, and the Z-axis moving unit 33 include a well-known ball screw provided rotatably around its axis, a well-known pulse motor for rotating the ball screw around its axis, and a well-known guide rail for supporting the chuck table 10 or the processing unit 20 movably in the X-axis, Y-axis, or Z-axis directions. The X-axis moving unit, the Y-axis moving unit 32, and the Z-axis moving unit 33 include a well-known position detector for detecting the position of the chuck table 10 or the processing unit 20 in the X-axis, Y-axis, or Z-axis directions, and output the position detected by the position detector to the control unit 98. As shown in FIG. 1, the processing device 1 is equipped with two processing units 20, that is, a two-spindle dicer, a so-called facing dual type cutting device.

[0016] One of the processing units 20 is provided on one of the pillars of a gate-shaped support frame 3 erected from the device main body 2 via a Y-axis moving unit 32, a Z-axis moving unit 33, etc., as shown in Fig. 1. The other processing unit 20 is provided on the other pillar that stands upright from the device main body 2 of the support frame 3 via a Y-axis moving unit 32, a Z-axis moving unit 33, etc., as shown in Fig. 1. The pillars are connected at their upper ends by a horizontal beam.

[0017] The processing device 1 also includes an imaging unit 25 that images the workpiece 100 held on the holding surface 11 of the chuck table 10. In the first embodiment, the imaging unit 25 is attached to one of the processing units 20 and moves integrally with the one of the processing units 20. The imaging unit 25 includes a CCD camera that images an area to be divided of the workpiece 100 held on the chuck table 10 before cutting. The CCD camera images the workpiece 100 held on the chuck table 10 to obtain an image for performing alignment to align the workpiece 100 and the cutting blade 21, and outputs the obtained image to the control unit 98.

[0018] The processing device 1 rotates the cutting blade 21 and moves the cutting blade 21 relative to the workpiece 100 held on the chuck table 10 along the planned division line 102 using the X-axis moving unit, the Y-axis moving unit 32 and the Z-axis moving unit 33, thereby cutting the workpiece 100 along the planned division line 102 with the cutting blade 21.

[0019] The cassette placement section 40 is a placement table on which a cassette 45, which is a container for accommodating a plurality of workpieces 100, is placed, and the placed cassette 45 is raised and lowered in the Z-axis direction. The carry-in / out unit 50 holds the workpiece 100 from below on a holding surface 51, and places the workpiece 100 in and out of the cassette 45. The cleaning device 55 suction-holds the workpiece 100 after cutting on a holding surface 57 of a chuck table 56 similar to the chuck table 10, and cleans the workpiece 100.

[0020] The transport unit 60 transports the workpiece 100 between the cassette 45 placed on the cassette placement section 40 and the chuck tables 10 and 56. In the example of the first embodiment shown in FIG. 1, the transport unit 60 includes a first transport unit 60 (hereinafter, indicated by reference numeral 60-1) that transports the workpiece 100 between the carry-in / out unit 50 and the chuck table 10, and a second transport unit 60 (hereinafter, indicated by reference numeral 60-2) that transports the workpiece 100 between the chuck table 10 and the chuck table 56 of the cleaning device 55. The first transport unit 60-1 transports the workpiece 100 before cutting from the carry-in / out unit 50 and transports it to the chuck table 10. The second transport unit 60-2 transports the workpiece 100 after cutting from the chuck table 10 and transports it to the chuck table 56 of the cleaning device 55. The second transport unit 60-2 carries the cleaned workpiece 100 out of the chuck table 56 of the cleaning device 55 and carries it into the carry-in / out unit 50.

[0021] As shown in FIG. 1, the transport unit 60 includes a base 61 and a moving unit 62 for moving the base 61. The moving unit 62 includes a unit support arm 63 having the base 61 at its tip, a Y-axis moving mechanism 64 for moving the unit support arm 63 in the Y-axis direction, and a lifting mechanism 65 provided at the tip of the unit support arm 63 for moving the base 61 in the Z-axis direction. The Y-axis moving mechanism 64 is provided on a horizontal beam 7 connecting a pair of columns 5, 6 of a gate-shaped second support frame 4 that stands upright from the device body 2 and is provided closer to the loading / unloading area than the support frame 3. The Y-axis moving mechanism 64 is composed of a well-known ball screw that is provided rotatably around its axis, a well-known pulse motor that rotates the ball screw around its axis, and a well-known guide rail that supports the unit support arm 63 movably in the Y-axis direction. The lifting mechanism 65 is composed of a well-known air cylinder.

[0022] 2, 3 and 4, the base part 61 includes a disk-shaped base 66, a non-contact suction holder 67, a support part 68, and an outer peripheral support member 69. The base 66 is attached to the lower end of a rod of an elevation mechanism 65 of the moving unit 62. Therefore, the moving unit 62 moves the base 66. In the example of the first embodiment shown in FIG. 2, three non-contact suction holders 67 are fixed at equal intervals in the circumferential direction of the base 66.

[0023] The non-contact type suction holder 67 comprises a thick, disk-shaped suction holder main body 71, a fluid jetting part 73 which jets air 200 along a lower surface 72 formed flat along the horizontal direction of the suction holder main body 71 from the centre of the lower surface 72, and a communicating tube 74 which is connected to the upper surface of the suction holder main body 71 and communicates with the fluid jetting part 73. The communicating tube 74 is formed in a cylindrical shape standing upright from the centre of the upper surface of the suction holder main body 71, and is connected to a pressurized air supply source 76, which is a fluid supply source, via an opening / closing valve 75, as shown in Fig. 2.

[0024] The non-contact suction holder 67 is fixed to the base 66 by having a communicating tube 74 passed through a through hole 77 that penetrates the base 66, and the outer circumferential side of a protruding portion 78 that protrudes radially outward of the communicating tube 74 being sandwiched between two members of the support portion 68 above the through hole 77, and a bolt 79 that passes through the support portion 68 being screwed into the base 66.

[0025] The non-contact suction holder 67 generates negative pressure in the center of the underside 72 side by Bernoulli's principle by injecting air 200 supplied from a pressurized air supply source 76 via an on-off valve 75 and a connecting pipe 74 along the underside 72 of the suction holder main body 71 by a fluid ejection part 73, and this negative pressure sucks the workpiece 100 with the underside 72 as the holding surface. When the workpiece 100 approaches the non-contact suction holder 67, the air 200 flowing between the underside 72 of the suction holder main body 71 and the workpiece 100 acts as a repulsive force, preventing contact with the workpiece 100, and the non-contact suction holder 67 sucks the workpiece 100 in a non-contact state as shown in Figures 3 and 4.

[0026] The outer peripheral support member 69 is fixed to the base 66 and contacts the outer edge of the workpiece 100 to restrict the horizontal movement of the workpiece 100. In the example of the first embodiment shown in FIG. 2, three outer peripheral support members 69 are fixed to the base 66 at equal intervals in the circumferential direction. The outer peripheral support members 69 are arranged between the non-contact suction holders 67 adjacent to each other along the circumferential direction of the base 66 and are arranged closer to the outer periphery of the base 66 than the non-contact suction holders 67. The outer peripheral support member 69 is fixed to the base 66 by screwing in a bolt 81 that penetrates the base 66, and the lower surface 82 is gradually inclined upward toward the center of the base 66. The outer peripheral support member 69 contacts the outer edge of the workpiece 100 with the inclined lower surface 82 as described above, and restricts the horizontal movement of the workpiece 100 sucked by the non-contact suction holder 67 in a non-contact state.

[0027] 1, in the first embodiment, the measuring unit 85 is indirectly attached to one of the processing units 20 via the imaging unit 25, and moves integrally with the one of the processing units 20 and the imaging unit 25. That is, the measuring unit 85 moves along the Y-axis direction and the Z-axis direction by the Y-axis moving unit 32 and the Z-axis moving unit 33, respectively. Note that the measuring unit 85 may be directly attached to one of the processing units 20.

[0028] 5 and 6, the measurement unit 85 is a back pressure type sensor, and includes an ejection nozzle 86 that ejects air 300 toward the holding surface 51 of the carry-in / out unit 50 and the workpiece 100 held on the holding surface 51. The ejection nozzle 86 is fixed to a piston rod 89 of an air cylinder 88 attached to the imaging unit 25, as shown in FIG.

[0029] The ejection nozzle 86 is connected to an air supply source 92 via a first path 91. The air supply source 92 is also connected to a second path 93. The second path 93 is opened to the atmosphere via a throttle valve 94. Air 300 (see FIG. 6) is supplied from the air supply source 92 to the first path 91 and the second path 93 at an appropriate ratio. The air 300 flowing through the first path 91 is supplied to the ejection nozzle 86.

[0030] A differential pressure sensor 95 is connected between the first path 91 and the second path 93. The differential pressure sensor 95 includes a diaphragm 96. The differential pressure sensor 95 is electrically connected to a control unit 98. The diaphragm 96 is displaced according to the difference between the pressure in the first path 91 and the pressure in the second path 93, and a voltage corresponding to the amount of displacement is output from the differential pressure sensor 95 to the control unit 98.

[0031] Air 300 is supplied from the air supply source 92 to the first path 91 and the second path 93, and the voltage output when there is no workpiece 100 in the direction of air 300 being ejected from the ejection port 87 of the ejection nozzle 86 can be set to 1 volt (1 V), for example, by adjusting the throttle valve 94 formed at the tip of the second path 93. The state where there is no workpiece 100 in the direction of air 300 being ejected from the ejection port 87 includes, for example, a state where the workpiece 100 is 5 mm or more away.

[0032] The ejection nozzle 86 has an ejection port 87 at the tip facing the workpiece 100, and by operating the air cylinder 88 to lower the piston rod 89, the ejection port 87 can be brought closer to the workpiece 100.

[0033] A limit switch 97 is disposed below the piston rod 89 to limit the downward movement of the jet nozzle 86 and to detect whether the jet nozzle 86 is in the operating position. The limit switch 97 is connected to a control unit 98, and detects whether the jet nozzle 86 is in the operating position or the non-operating position and notifies the control unit 98 of the result.

[0034] If there is no obstacle in the direction in which air 300 is ejected from the ejection port 87 of the ejection nozzle 86, the first path 91 will be open to the atmosphere as well as the second path 93, so the pressure in the first path 91 and the pressure in the second path 93 will be in equilibrium, and the diaphragm 96 of the differential pressure sensor 95 will be in an equilibrium state. At this time, since the output voltage in the equilibrium state is set to 1V, the voltage value output from the differential pressure sensor 95 will be 1V.

[0035] On the other hand, when the nozzle 86 is close to the workpiece 100, the nozzle 87 becomes blocked by the workpiece 100, the pressure in the first path 91 changes, the equilibrium state of the diaphragm 96 is disturbed, and a voltage corresponding to the distance between the nozzle 87 and the workpiece 100 is output from the differential pressure sensor 95.

[0036] The control unit 98 controls the operation of various components of the processing device 1, and causes the processing device 1 to perform processing by the processing unit 20, transport processing by the transport unit 60, measurement processing by the measurement unit 85, and the like. In the first embodiment, the control unit 98 includes a computer system. The computer system included in the control unit 98 includes an arithmetic processing device having a microprocessor such as a CPU (Central Processing Unit), a storage device having a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), and an input / output interface device. The arithmetic processing device of the control unit 98 performs arithmetic processing according to a computer program stored in the storage device of the control unit 98, and outputs a control signal for controlling the processing device 1 to each component of the processing device 1 via the input / output interface device of the control unit 98.

[0037] The control unit 98 reads the voltage value output by the differential pressure sensor 95, and controls the Z-axis moving unit 33 and the air cylinder 88 according to the voltage value so that the jet nozzle 86 does not hit the holding surface 51 of the carry-in / out unit 50 or the surface 101 of the workpiece 100 held on the holding surface 51. The control unit 98 includes a memory unit 99, which stores in advance, for example, the relationship between the distance from the jet outlet 87 of the jet nozzle 86 to the holding surface 51 of the carry-in / out unit 50 or the surface 101 of the workpiece 100 held on the holding surface 51, and the voltage output from the differential pressure sensor 95. The memory unit 99 is realized by a storage device of a computer system included in the control unit 98.

[0038] Therefore, the control unit 98 can determine the distance between the ejection port 87 of the ejection nozzle 86 and the holding surface 51 of the loading / unloading unit 50 or the surface 101 of the workpiece 100 held on the holding surface 51, based on the voltage output from the differential pressure sensor 95 and the corresponding information stored in the memory unit 99. For example, when the output from the differential pressure sensor 95 is 5 V, the distance between the ejection port 87 and the holding surface 51 of the loading / unloading unit 50 or the surface 101 of the workpiece 100 held on the holding surface 51 can be determined to be 100 μm.

[0039] Next, this specification will explain the operation of the processing device 1 according to the embodiment 1 with reference to the drawings. The control unit 98 of the processing device 1 causes the carry-in / out unit 50 to hold the workpiece 100 before cutting in the cassette 45 on the holding surface 51, and temporarily stops the carry-in / out unit 50 in a state where the workpiece 100 is removed from the cassette 45.

[0040] As shown by a solid line in Fig. 6, the control unit 98 controls the Z-axis moving unit 33 to move the nozzle 87 of the ejection nozzle 86 sufficiently close to the surface 101 of the workpiece 100 held on the holding surface 51 of the temporarily stopped carry-in / out unit 50, and determines the Z-axis position of the nozzle 87 of the ejection nozzle 86 based on information on the Z-axis position obtained from the Z-axis moving unit 33 and the air cylinder 88. The control unit 98 ejects air 300 from the nozzle 87 of the ejection nozzle 86 toward the workpiece 100 by the measurement unit 85, and determines the distance between the nozzle 87 of the ejection nozzle 86 and the surface 101 of the workpiece 100 by referring to the relationship previously stored in the memory unit 99. The control unit 98 determines the Z-axis position of the surface 101 of the workpiece 100 based on the position of the nozzle 87 in the Z-axis direction and the distance between the nozzle 87 and the surface 101 of the workpiece 100.

[0041] As shown by the dotted line in Figure 6, the control unit 98 controls the Z-axis moving unit 33 to move the outlet 87 of the ejection nozzle 86 sufficiently close to the exposed portion of the holding surface 51 of the temporarily stopped loading / unloading unit 50, and then performs processing similar to that used to determine the Z-axis position of the surface 101 of the workpiece 100 held on the holding surface 51 of the temporarily stopped loading / unloading unit 50 described above, to determine the Z-axis position of the exposed portion of this holding surface 51.

[0042] The control unit 98 determines the thickness of the workpiece 100 by using the measurement unit 85 to determine a difference obtained by subtracting the Z-axis position of the portion where the holding surface 51 of the carry-in / out unit 50 is exposed from the Z-axis position of the surface 101 of the workpiece 100 held on the holding surface 51 of the carry-in / out unit 50. Here, the thickness of the workpiece 100 refers to the height of the surface 101 of the workpiece 100 based on the holding surface 51 of the carry-in / out unit 50. In this way, the measurement unit 85 measures the thickness (height) of the workpiece 100 held on the holding surface 51 of the carry-in / out unit 50 without any of the parts of the measurement unit 85 coming into contact with the workpiece 100, i.e., in a non-contact state.

[0043] The control unit 98 controls the transport unit 60 to adjust the height of the lower surface 72 (holding surface) of the non-contact suction holder 67 according to the thickness of the workpiece 100 measured by the measurement unit 85 using the lifting mechanism 65 of the moving unit 62, and disposes the non-contact suction holder 67 at a position where the distance between the lower surface 72 of the non-contact suction holder 67 and the surface 101 (held surface) of the workpiece 100 is within a predetermined range. Here, the predetermined range refers to the range of the distance between the lower surface 72 of the non-contact suction holder 67 and the surface 101 of the workpiece 100 that allows the non-contact suction holder 67 to apply a sufficient negative pressure to the workpiece 100 and suck and hold the workpiece 100 with a stable suction force. That is, the control unit 98 adjusts the height of the lower surface 72 (holding surface) of the non-contact suction holder 67 based on the holding surface 51 that holds the workpiece 100, to a height that is higher by the thickness of the workpiece 100 than the height of the predetermined range of intervals, based on the holding surface 51 that holds the workpiece 100, according to the thickness of the workpiece 100 measured by the measuring unit 85. Specifically, in the first embodiment, as shown in Figs. 3 and 4, the control unit 98 adjusts heights 111, 112 of the lower surface 72 of the non-contact suction holder 67 based on the holding surface 51 of the carry-in / out unit 50, by the moving unit 62, to a height obtained by adding the thickness of the workpiece 100 measured by the measuring unit 85 to the predetermined range of intervals. When the thickness of the workpiece 100 is relatively thin as shown in Figure 3, the height 111 of the lower surface 72 of the non-contact suction holder 67 based on the holding surface 51 of the loading / unloading unit 50 is adjusted to be lower by the amount of the thinner thickness of the workpiece 100, and when the thickness of the workpiece 100 is relatively thick as shown in Figure 4, the height 112 of the lower surface 72 of the non-contact suction holder 67 based on the holding surface 51 of the loading / unloading unit 50 is adjusted to be higher by the amount of the thicker thickness of the workpiece 100.

[0044] After adjusting the height of the lower surface 72 of the non-contact suction holder 67, the control unit 98 causes the non-contact suction holder 67 to inject air 200 from the fluid ejection portion 73 along the lower surface 72 of the suction holder body 71, and sucks and holds the workpiece 100 in a non-contact state by the negative pressure on the lower surface 72 side generated by Bernoulli's principle. After the non-contact suction holder 67 sucks and holds the workpiece 100, the control unit 98 causes the moving unit 62 to transport the workpiece 100 sucked and held by the non-contact suction holder 67 onto the holding surface 11 of the chuck table 10. After the moving unit 62 transports the workpiece 100 onto the holding surface 11 of the chuck table 10, the control unit 98 causes the non-contact suction holder 67 to stop the ejection of air 200 to stop the suction and holding of the workpiece 100, thereby placing the workpiece 100 on the holding surface 11 of the chuck table 10.

[0045] In the first embodiment, since the processing unit 20 is a cutting unit, the thickness of the workpiece 100 does not change significantly due to cutting. Therefore, even when the control unit 98 holds the workpiece 100 after cutting or cleaning, it is not necessary to measure the thickness of the workpiece 100 again, and the control unit 98 can adjust the height of the lower surface 72 of the non-contact suction holder 67 according to the thickness of the workpiece 100 measured when the workpiece 100 before cutting in the cassette 45 is taken out by the carry-in / out unit 50. Specifically, when the control unit 98 suction-holds the workpiece 100 after cutting or cleaning on the holding surfaces 11, 57 of the chuck tables 10, 56, the control unit 98 adjusts the height of the lower surface 72 of the non-contact suction holder 67 based on the holding surfaces 11, 57 of the chuck tables 10, 56 to a height obtained by adding the predetermined range of intervals to the thickness of the workpiece 100 before cutting measured by the measuring unit 85.

[0046] The processing apparatus 1 of embodiment 1 having the above-mentioned configuration measures the thickness (height) of the workpiece 100 using the measuring unit 85 and adjusts the height of the lower surface 72 of the non-contact suction holder 67 in accordance with the measurement result. Therefore, even if the thickness of the workpiece 100 taken out of the cassette 45 changes, the non-contact suction holder 67 can apply sufficient negative pressure to the workpiece 100 in accordance with the thickness of the workpiece 100, thereby achieving the effect of transporting the workpiece 100 with a stable suction force.

[0047] Furthermore, since the measuring unit 85 of the processing apparatus 1 according to the first embodiment is a back pressure type sensor, the thickness (height) of the workpiece 100 can be measured in a non-contact state. Therefore, the processing apparatus 1 according to the first embodiment can perform the measurement of the thickness of the workpiece 100, the suction holding, and the transportation in a non-contact state, and can favorably maintain the quality of the front surface 101 side of the workpiece 100.

[0048] [Embodiment 2] A processing device 1 according to a second embodiment of the present invention will be described. The processing device 1 according to the second embodiment is the same as that of the first embodiment, except that the measurement unit 85 is changed from a back pressure sensor to an optical sensor. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof will be omitted.

[0049] The measuring unit 85 according to the second embodiment includes an irradiating section that irradiates a laser beam toward the holding surface 51 of the carry-in / out unit 50 or the surface 101 of the workpiece 100 held on the holding surface 51, and a light receiving section that receives the reflected light of the irradiated laser beam reflected by the holding surface 51 or the surface 101. The measuring unit 85 according to the second embodiment determines the distance from the measuring unit 85 to the holding surface 51 of the carry-in / out unit 50 or the surface 101 of the workpiece 100 held on the holding surface 51, based on the reflected light received by the light receiving section from the irradiation of the laser beam by the irradiating section. The measuring unit 85 according to the second embodiment performs the same processes as those of the first embodiment for the rest, and measures the thickness (height) of the workpiece 100 held on the holding surface 51 of the carry-in / out unit 50 without any of the sections of the measuring unit 85 coming into contact with the workpiece 100, i.e., in a non-contact state, as in the first embodiment.

[0050] The processing apparatus 1 of the second embodiment having the above-mentioned configuration is the same as that of the first embodiment except that the measurement unit 85 has been changed from a back pressure sensor to an optical sensor, and therefore has the same effects as those of the first embodiment.

[0051] [Modifications] A processing device 1 according to a modified example of the first and second embodiments of the present invention will be described. The processing device 1 according to the modified example is obtained by changing the processing unit 20 in the first and second embodiments, and other configurations are generally the same. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0052] When the processing unit 20 is changed to a laser processing unit that irradiates a laser beam onto the workpiece 100 to perform laser processing, or a cleaning unit that cleans the workpiece 100, the thickness of the workpiece 100 does not change significantly due to processing, etc., as in the first and second embodiments. For this reason, even when holding the workpiece 100 after processing or cleaning, as in the first and second embodiments, the control unit 98 adjusts the height of the lower surface 72 of the non-contact suction holder 67 in accordance with the thickness of the workpiece 100 measured when the unprocessed workpiece 100 in the cassette 45 is taken out by the carry-in / out unit 50.

[0053] When the processing unit 20 is changed to a grinding unit that grinds the workpiece 100 with a grinding wheel, the thickness of the workpiece 100 changes due to the grinding process. For this reason, when the control unit 98 holds the workpiece 100 after processing, cleaning, etc., it measures the thickness of the workpiece 100 after grinding again by the measuring unit 85 on the holding surface 11 of the chuck table 10, for example, and adjusts the height of the lower surface 72 of the non-contact suction holder 67 according to the newly measured thickness of the workpiece 100 after grinding.

[0054] The machining device 1 according to the modified example having the above-mentioned configuration is obtained by modifying the machining unit 20 in the first and second embodiments, and therefore provides the same effects as those of the first and second embodiments.

[0055] The present invention is not limited to the above embodiment. That is, various modifications can be made without departing from the gist of the present invention. In the above embodiment, the measurement unit is a back pressure sensor or an optical sensor, but the present invention is not limited to this, and any type of sensor can be used as long as it can measure the thickness of the workpiece held on the holding surface of the carry-in / out unit. In addition, the sensor of the measurement unit 85 may be arranged independently of the imaging unit 25 and fixed to the lifting mechanism 65. In this case, the sensor is arranged above the carry-in / out unit 50 that holds the workpiece 100 carried out from the cassette 45, and moves up and down relative to the holding surface 51 of the carry-in / out unit 50, and detects the holding surface 51 and the surface 101 of the workpiece 100 while determining the position (height) of the sensor. [Explanation of symbols]

[0056] 1 Processing equipment 10 Chuck table 20 Processing Unit 40 Cassette placement section 45 Cassette 60 Transport Unit 61 Base 62 Mobile Unit 67 Non-contact suction retainer 85 Measurement Units 100 Workpiece 200,300 Air

Claims

[Claim 1] A processing apparatus including a chuck table for holding a plate-shaped workpiece, a processing unit for processing the workpiece held on the chuck table, a cassette placement section for placing a cassette containing the workpiece, a transport unit for transporting the workpiece between the cassette placed on the cassette placement section and the chuck table, and a measurement unit for measuring a thickness of the workpiece, The transport unit includes: a base portion including a non-contact suction holder that generates negative pressure by injecting air and sucks the workpiece in a non-contact state; A moving unit that moves the base portion, The measurement unit is a back pressure sensor or an optical sensor, and measures the thickness of the workpiece in a non-contact manner. A processing device which adjusts the height of the non-contact suction holder according to the thickness of the workpiece measured by the measurement unit, and transports the workpiece by positioning the non-contact suction holder at a position where the distance between the non-contact suction holder and the surface of the workpiece is within a specified range.

Images