Cutting device

Abstract

To provide a cutting device capable of suppressing collision of a microscope with a workpiece held on a chuck table when implementing dressing of a cutting blade.SOLUTION: A cutting device 1 comprises a chuck table 10, a cutting unit 20 and a moving unit for moving the chuck table 10 in relative to the cutting unit 20. The chuck table 10 includes a main chuck table 11 holding a workpiece 200-1 and a sub chuck table 12 being adjacent to the main chuck table 11 and holding a dress board 210 on a dress board holding surface 121. The sub chuck table 12 includes a sub chuck table lifting unit 13 for changing a height of the dress board holding surface 121 between a dressing position corresponding to a height of a top face of the thick workpiece 200-1, which is held by the main chuck table 11 and becomes as high as or higher than a predetermined level, and a retraction position which is lower than the dressing position.SELECTED DRAWING: Figure 6

Description

[Technical Field]

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

[0002] Cutting machines that use cutting blades to cut and divide thin workpieces such as wafers are sometimes used to cut workpieces that are 2 mm or thicker (usually 0.5 mm or thinner). When cutting thick workpieces, the cutting machine may use a special jig to adjust the height of the chuck table.

[0003] In addition, the cutting device may hold a dressing board on the sub-chuck table to sharpen the cutting edge of the cutting blade, which has become clogged or dulled due to cutting and has reduced cutting ability, and to remove cutting chips that have adhered to the cutting edge of the cutting blade, thereby restoring the cutting ability of the cutting edge of the cutting blade (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5636213 Summary of the Invention [Problem to be solved by the invention]

[0005] When a cutting device dresses a thick workpiece held on the chuck table by cutting the cutting blade into a dressing board held on a nearby sub-chuck table, there has been a problem in that the blade cover and nozzle that cover the cutting blade, and the microscope arranged in the same straight line as the chuck table and sub-chuck table, collide with the workpiece held on the chuck table.

[0006] Therefore, an object of the present invention is to provide a cutting device that can prevent a microscope from colliding with a workpiece held on a chuck table when dressing a cutting blade. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the object, the cutting device of the present invention is a cutting device comprising a chuck table that holds a workpiece on a holding surface, a cutting unit that cuts the workpiece held by the chuck table with a cutting blade, and a movement unit that moves the chuck table relative to the cutting unit, wherein the chuck table comprises a main chuck table that holds the workpiece, and a sub-chuck table that is adjacent to the main chuck table and holds a dress board used for dressing the cutting blade on its dress board holding surface, and the sub-chuck table comprises a sub-chuck table lifting unit that changes the height of the dress board holding surface between a dressing position corresponding to the height of the upper surface of the workpiece held by the main chuck table, which is at least a predetermined height, and a retracted position that is lower than the dressing position. The sub-chuck table lifting unit rotates the dress board holding surface from an upward direction to a horizontal direction, and moves the dress board from the dressing position to the retracted position. It is characterized by the following. [Effects of the Invention]

[0010] The present invention has the effect of preventing the microscope from colliding with the workpiece held on the chuck table when dressing the cutting blade. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a perspective view showing an example of the configuration of a cutting device according to the first embodiment. [Figure 2] FIG. 2 is a perspective view showing an example of the configuration of the sub-chuck table of the cutting device according to the first embodiment. [Figure 3] FIG. 3 is a perspective view showing a state in which the sub-chuck table shown in FIG. 2 is positioned at a dressing position. [Figure 4]FIG. 4 is a side view, partly in section, schematically showing the cutting device shown in FIG. 1 cutting a thin workpiece. [Figure 5] FIG. 5 is a side view, partly in section, schematically showing the cutting device shown in FIG. 1 cutting a thick workpiece. [Figure 6] FIG. 6 is a side view, partly in section, schematically showing the state in which the cutting device shown in FIG. 5 is performing dressing. [Figure 7] FIG. 7 is a perspective view showing an example of the configuration of a sub-chuck table positioned at the dressing position of the cutting device according to the second embodiment. [Figure 8] FIG. 8 is a perspective view showing a state in which the sub-chuck table shown in FIG. 7 is positioned at a retracted position. [Figure 9] FIG. 9 is a side view, partly in cross section, schematically showing a state in which the cutting device according to the second embodiment cuts a thick workpiece. [Figure 10] FIG. 10 is a side view, partly in section, schematically showing the state in which the cutting device shown in FIG. 9 is performing dressing. DETAILED DESCRIPTION OF THE INVENTION

[0012] Modes (embodiments) 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 1. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the configuration can be made within the scope of the gist of the present invention.

[0013] [Embodiment 1] A cutting device 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 an example of the configuration of the cutting device according to the first embodiment. Fig. 2 is a perspective view showing an example of the configuration of a sub-chuck table of the cutting device according to the first embodiment. Fig. 3 is a perspective view showing a state in which the sub-chuck table shown in Fig. 2 is positioned at the dressing position.

[0014] The cutting device 1 shown in FIG. 1 according to embodiment 1 is a processing device that cuts a thick workpiece 200-1, which is a workpiece having a thickness equal to or greater than a predetermined thickness, or a thin workpiece 200-2 (shown in FIG. 4), which is a workpiece having a thickness less than the predetermined thickness.

[0015] (workpiece) The thick workpiece 200-1 to be processed by the cutting device 1 according to the first embodiment has a thickness of 2 mm or more (preferably, a thickness of 5 mm or more and 100 mm or less), such as an electronic component, a ceramic substrate made of ceramics, or a glass substrate made of glass. In the first embodiment, the thick workpiece 200-1 has a rectangular planar shape.

[0016] The thin workpiece 200-2 has a thickness of 1 mm or less, and is, for example, a wafer such as a disk-shaped semiconductor wafer or optical device wafer made of a base material such as silicon, gallium arsenide, SiC (silicon carbide), or sapphire, or a resin package substrate such as a rectangular QFN (Quad Flat No leaded) package substrate having multiple device chips sealed with resin.

[0017] (cutting equipment) The cutting device 1 according to the first embodiment is a processing device that holds any one of workpieces 200-1, 200-2 on a chuck table 10 and cuts any one of workpieces 200-1, 200-2. As shown in Fig. 1 , the cutting device 1 includes the chuck table 10 that holds any one of workpieces 200-1, 200-2 by suction, a cutting unit 20 that cuts any one of workpieces 200-1, 200-2 held on the chuck table 10 with a cutting blade 21, a microscope 30 that photographs any one of workpieces 200-1, 200-2 held on the chuck table 10, and a control unit 100.

[0018] 1, the cutting device 1 also includes a moving unit 40 that moves the chuck table 10 relative to the cutting unit 20. The moving unit 40 includes at least an X-axis moving unit 41, which is a processing feed unit that performs processing feed on the chuck table 10 in the X-axis direction parallel to the horizontal direction, a Y-axis moving unit 42, which is an indexing feed unit that performs indexing feed on the cutting unit 20 in the Y-axis direction that is parallel to the horizontal direction and perpendicular to the X-axis direction, a Z-axis moving unit 43, which is a cutting feed unit that performs cutting feed on the cutting unit 20 in the Z-axis direction that is parallel to the vertical direction and perpendicular to both the X-axis and Y-axis directions, and a rotational moving unit 44 that rotates the chuck table 10 around an axis parallel to the Z-axis direction.

[0019] The X-axis moving unit 41 moves the chuck table 10 and the rotational moving unit 44 in the X-axis direction, which is the processing feed direction, thereby relatively feeding the chuck table 10 and the cutting unit 20 along the X-axis. The Y-axis moving unit 42 is installed on the support frame 3 that stands upright from the device main body 2, and moves the cutting unit 20 in the Y-axis direction, which is the indexing feed direction, thereby relatively feeding the chuck table 10 and the cutting unit 20 along the Y-axis.

[0020] The Z-axis moving unit 43 is installed on the support frame 3 that stands upright from the device body 2, and moves the cutting unit 20 in the Z-axis direction, which is the cutting feed direction, to feed the chuck table 10 and the cutting unit 20 relatively along the Z-axis. The rotational movement unit 44 is provided so as to be movable in the X-axis direction by the X-axis movement unit 41.

[0021] The X-axis moving unit 41, the Y-axis moving unit 42, and the Z-axis moving unit 43 each include a well-known ball screw rotatably mounted about its axis, a well-known motor for rotating the ball screw about its axis, and a well-known guide rail for supporting the chuck table 10 or the cutting unit 20 movably in the X-axis, Y-axis, or Z-axis direction. The rotational moving unit 44 also includes a motor for rotating the chuck table 10 about its axis.

[0022] The chuck table 10 has a main chuck table 11 that holds one of the workpieces 200-1, 200-2, and a sub-chuck table 12 that holds the dress board 210, which is the workpiece. The main chuck table 11 is disk-shaped and suction-holds one of the workpieces 200-1, 200-2 on a holding surface 111 that is parallel to the horizontal direction. The main chuck table 11 is rotated about an axis parallel to the Z-axis direction by a rotary movement unit 44. The main chuck table 11 is moved in the X-axis direction by an X-axis movement unit 41 together with the rotary movement unit 44 between a processing area below the cutting unit 20 and a load / unload area that is spaced from below the cutting unit 20 and where the workpieces 200-1, 200-2 are loaded and unloaded.

[0023] The main chuck table 11 has suction grooves 112 formed in a holding surface 111, the suction grooves 112 being connected to a vacuum suction source (not shown). The main chuck table 11 sucks and holds one of the workpieces 200-1, 200-2 placed on the holding surface 111 by the suction grooves 112 being sucked by the vacuum suction source. The periphery of the chuck table 10 is covered by a table cover 4 attached to the outer circumferential surface of the rotary movement unit 44.

[0024] A bellows member 5 that covers the X-axis moving unit 41 is attached to the table cover 4. A pair of bellows members 5 is provided. One bellows member 5 is attached to the table cover 4 and the end of the device main body 2 on the front side in the X-axis direction in FIG. 1, and the other bellows member 5 is attached to the table cover 4 and the end of the device main body 2 on the rear side in the X-axis direction. Each bellows member 5 is flexible and can expand and contract in the X-axis direction, allowing the table cover 4, i.e., the chuck table 10, to move in the X-axis direction. Each bellows member 5 prevents cutting water and the like from adhering to the X-axis moving unit 41, etc.

[0025] (Sub-chuck table) The sub-chuck table 12 is adjacent to the main chuck table 11 and suction-holds the dress board 210 on a flat dress board holding surface 121. The dress board 210 sharpens the cutting edge of the cutting blade 21, which has become clogged or dulled and reduced in cutting ability due to cutting by the cutting edge of the cutting blade 21, and removes cutting chips adhering to the cutting edge of the cutting blade 21, thereby restoring the cutting ability of the cutting edge of the cutting blade 21. The act of cutting the dress board 210 with the cutting edge of the cutting blade 21, sharpening the cutting edge of the cutting blade 21, and restoring the cutting ability of the cutting edge of the cutting blade 21 is called dressing (also called dressing).

[0026] That is, the dressing board 210 is used for dressing the cutting blade 21. The dressing board 210 has abrasive grains fixed with a bonding material, and in the first embodiment, is formed into a rectangular flat plate shape with a planar shape equivalent to the thickness of the thin workpiece 200-2.

[0027] The sub-chuck table 12 is installed on the table cover 4 and is moved in the X-axis direction by the X-axis moving unit 41 together with the main chuck table 11 and the rotational moving unit 44. As shown in Figures 2 and 3 , the sub-chuck table 12 includes a sub-chuck table lifting / lowering unit 13, a holding member 14 having the above-mentioned dress board holding surface 121, an orientation adjustment mechanism 15 that attaches the holding member 14 to the sub-chuck table lifting / lowering unit 13 and adjusts the orientation of the dress board holding surface 121, and a cover 16.

[0028] The sub-chuck table lifting unit 13 changes the height of the dress board holding surface 121 between a dressing position corresponding to the height of the upper surface of the thick workpiece 200-1 held by the main chuck table 11 and having a height equal to or higher than a predetermined height, and a retracted position lower than the dressing position. The sub-chuck table lifting unit 13 is a so-called air cylinder including a cylinder 131 installed on the table cover 4 and an extendable rod 132 extending from the cylinder 131 along the Z-axis direction and having a holding member 14 attached to its upper end.

[0029] In the first embodiment, the sub-chuck table lifting unit 13 retracts the telescopic rod 132 to position the dress board holding surface 121 of the holding member 14 at the retracted position, as shown in Fig. 2. In the first embodiment, at the retracted position, the dress board holding surface 121 of the holding member 14 is positioned on the same plane as the holding surface 111 of the main chuck table 11 in height in the Z-axis direction.

[0030] However, in the present invention, when in the retracted position, the dress board holding surface 121 of the holding member 14 is positioned so that when the cutting edge of the cutting blade 21 is cut into the dress board 210 held on the dress board holding surface 121, the lower end of the microscope 30 is positioned above the upper surface of the thin workpiece 200-2 held on the holding surface 111, and when the thin workpiece 200-2 held on the holding surface 111 is cut with the cutting blade 21, the lower end of the cutting edge of the cutting blade 21 is positioned above the upper surface of the dress board 210.Furthermore, as long as the difference in height in the Z-axis direction between the holding surfaces 111 and 121 is small, the height in the Z-axis direction does not necessarily have to be positioned on the same plane as the holding surface 111 of the main chuck table 11.

[0031] Alternatively, even when a thin workpiece 200-2 is being machined, if the dressing of the cutting blade 21 is performed with the sub-chuck table 12 in the dressing position, the retracted position of the sub-chuck table 12 may be at a height that does not hit the cutting blade 21 that processes the main chuck table 11, the blade cover that covers the cutting blade 21, or the cutting water nozzle 24.

[0032] In the first embodiment, the sub-chuck table lifting / lowering unit 13 extends the telescopic rod 132 to position the dress board holding surface 121 of the holding member 14 at the dressing position, as shown in Fig. 3. In the first embodiment, at the dressing position, the dress board holding surface 121 of the holding member 14 is positioned at a position higher in the Z-axis direction than the holding surface 111 of the main chuck table 11.

[0033] In the present invention, at the dressing position, when the cutting edge of the cutting blade 21 is cut into the dress board 210 held on the dress board holding surface 121, it is desirable that the lower end of the microscope 30 be positioned at a height equal to or higher than the upper surface of the thick workpiece 200-1 held on the holding surface 111. Also, in the present invention, at the dressing position, it is desirable that the dress board holding surface 121 of the holding member 14 be positioned at the same height as or higher than the upper surface of the thick workpiece 200-1 held on the holding surface 111 when the cutting edge of the cutting blade 21 is cut into the dress board 210 held on the dress board holding surface 121.

[0034] However, in the present invention, at the dressing position, the dress board holding surface 121 of the holding member 14 does not necessarily have to be positioned above the upper surface of the thick workpiece 200-1 held on the holding surface 111 of the main chuck table 11, as long as the difference in height in the Z-axis direction between the holding surfaces 111, 121 is small when the cutting edge of the cutting blade 21 is cut into the dress board 210 held on the dress board holding surface 121.

[0035] In the present invention, when the cutting edge of the cutting blade 21 cuts into the dress board 210 held on the dress board holding surface 121 positioned at the dressing position, the lower end of the microscope 30 is positioned above the upper surface of the thick workpiece 200-1 held on the holding surface 111, and the difference in height in the Z-axis direction between the holding surfaces 111 and 121 is small, this is referred to as the dress board holding surface 121 positioned at the dressing position of the holding member 14 being positioned at the same height in the Z-axis direction as the upper surface of the thick workpiece 200-1 held on the holding surface 111 of the main chuck table 11. In other words, in the present invention, it is desirable that the dress board holding surface 121 positioned at the dressing position of the holding member 14 be positioned at the same height in the Z-axis direction as the upper surface of the thick workpiece 200-1 held on the holding surface 111 of the main chuck table 11.

[0036] Furthermore, in the dressing position, the dress board holding surface 121 of the holding member 14 being at the same height as the upper surface of the thick workpiece 200-1 held on the holding surface 111 is referred to as being at a position (height) corresponding to the height of the upper surface of the thick workpiece 200-1 held by the main chuck table 11, which is at a predetermined height or higher. Thus, in embodiment 1, the sub-chuck table lifting unit 13 is an air cylinder that raises and lowers the dress board holding surface 121, and by raising and lowering the dress board holding surface 121, the dress board holding surface 121 is moved between the dressing position and the retracted position.

[0037] The holding member 14 has a rectangular plate-like shape in plan view, the same size as the dress board 210, and suction-holds the dress board 210 on a flat dress board holding surface 121. The holding member 14 has suction grooves 122 formed in the dress board holding surface 121, the suction grooves 122 being connected to a vacuum suction source (not shown). The holding member 14, i.e., the sub-chuck table 12, suctions and holds the dress board 210 placed on the dress board holding surface 121, as the suction grooves 122 are sucked by the vacuum suction source.

[0038] The orientation adjustment mechanism 15 is attached to the tip of the extendable rod 132 of the sub-chuck table lifting unit 13, and includes a support member 151 that supports the lower surface of the holding member 14 (the surface behind the dress board holding surface 121), and a plurality of adjustment members 152. The plurality of adjustment members 152 change the orientation of the holding member 14 relative to the support member 151. In the first embodiment, three adjustment members 152 are provided spaced apart from each other.

[0039] In the first embodiment, one of the three adjustment members 152 is a nut that is provided between the support member 151 and the holding member 14 and that is rotated about its axis relative to the screw shaft to change the height in the Z-axis direction of the position supported by the holding member 14. The remaining two adjustment members 152 are screws that are screwed into the support member 151 from the dress board holding surface 121 side and that are rotated about their axis to adjust the amount of screwing to change the height in the Z-axis direction of the position supported by the holding member 14. The orientation adjustment mechanism 15 adjusts the orientation of the dress board holding surface 121 by changing the height in the Z-axis direction of the position supported by each adjustment member 152 of the holding member 14. In the first embodiment, the orientation adjustment mechanism 15 adjusts each adjustment member 152 during periodic maintenance of the cutting device 1, etc., to adjust the height in the Z-axis direction of the position supported by each adjustment member 152 of the holding member 14 to a height that makes the dress board holding surface 121 parallel to the horizontal direction.

[0040] 2 and 3, the cover 16 covers the outer periphery of the cylinder 131 of the sub-chuck table lifting / lowering unit 13 to prevent chips from adhering to the sub-chuck table lifting / lowering unit 13, particularly to the telescopic rod 132, during cutting. The cover 16 is formed in a flat plate shape that covers the outer periphery of the cylinder 131 of the sub-chuck table lifting / lowering unit 13.

[0041] The cutting unit 20 is a processing unit in which a cutting blade 21 is attached to a spindle 23 and cuts one of the workpieces 200-1, 200-2 held on the main chuck table 11. The cutting unit 20 is provided so as to be movable in the Y-axis direction by a Y-axis movement unit 42 and in the Z-axis direction by a Z-axis movement unit 43 relative to one of the workpieces 200-1, 200-2 held on the main chuck table 11 or the dress board 210 held on the sub-chuck table 12. As shown in FIG. 1 , the cutting unit 20 is provided on a support frame 3 erected from the apparatus main body 2 via the Y-axis movement unit 42, the Z-axis movement unit 43, and the like. The cutting unit 20 can position the cutting blade 21 at any position on the holding surface 111 of the main chuck table 11 or on any position on the dress board holding surface 121 of the sub-chuck table 12 by the Y-axis movement unit 42 and the Z-axis movement unit 43.

[0042] The cutting unit 20 includes a cutting blade 21, a spindle housing 22 that is movable in the Y-axis and Z-axis directions by a Y-axis moving unit 42 and a Z-axis moving unit 43, a spindle 23 that is rotatable about its axis on the spindle housing 22 and has the cutting blade 21 attached to its tip, a spindle motor (not shown) that rotates the spindle 23 about its axis, and a cutting water nozzle 24 that supplies cutting water to the cutting blade 21.

[0043] The cutting blade 21 is an extremely thin cutting grindstone having a substantially ring shape. The cutting blade 21 is fixed to the tip of the spindle 23. In the first embodiment, the cutting blade 21 is a so-called hub blade including an annular circular base and an annular cutting edge disposed on the outer periphery of the circular base for cutting the workpiece 200. The cutting edge is formed to a predetermined thickness and is made of abrasive grains such as SiC, alumina, diamond, or CBN (Cubic Boron Nitride) and a bond (binding material) such as metal or resin for fixing the abrasive grains. In the present invention, the cutting blade 21 may be a so-called washer blade consisting only of the cutting edge. The axes of the cutting blade 21 and the spindle 23 of the cutting unit 20 are set parallel to the Y-axis direction.

[0044] The microscope 30 is fixed to the cutting unit 20 so as to move integrally with the cutting unit 20. In the first embodiment, the microscope 30 is disposed in a position where an objective lens facing the workpieces 200-1 and 200-2 held on the main chuck table 11 is aligned with the cutting blade 21 in the X-axis direction. The microscope 30 is equipped with an imaging element that captures an image of a region to be divided in either of the workpieces 200-1 and 200-2 held on the main chuck table 11 before cutting. The imaging element is, for example, a CCD (Charge-Coupled Device) imaging element or a CMOS (Complementary MOS) imaging element. The microscope 30 captures an image of either of the workpieces 200-1 and 200-2 held on the main chuck table 11 to obtain an image for performing alignment between either of the workpieces 200-1 and 200-2 and the cutting blade 21, and outputs the obtained image to the control unit 100. The microscope 30 also captures an image of the dress board 210 held on the sub-chuck table 12.

[0045] The cutting device 1 also includes an X-axis position detection unit (not shown) for detecting the position of the chuck table 10 in the X-axis direction, a Y-axis position detection unit (not shown) for detecting the position of the cutting unit 20 in the Y-axis direction, and a Z-axis position detection unit for detecting the position of the cutting unit 20 in the Z-axis direction. The X-axis position detection unit and the Y-axis position detection unit may be configured with a linear scale parallel to the X-axis direction or the Y-axis direction, and a read head. The Z-axis position detection unit detects the position of the cutting unit 20 in the Z-axis direction using motor pulses. The X-axis position detection unit, the Y-axis position detection unit, and the Z-axis position detection unit output the position of the chuck table 10 in the X-axis direction and the position of the lower end of the cutting blade of the cutting unit 20 in the Y-axis direction or the Z-axis direction to the control unit 100.

[0046] In the first embodiment, the positions of the chuck table 10 and the cutting unit 20 of the cutting device 1 in the X-axis direction, Y-axis direction, and Z-axis direction are determined based on a predetermined reference position (not shown). In the first embodiment, the reference position of the cutting unit 20 in the Z-axis direction is a position where the holding surface 111 of the chuck table 10 and the lower end of the cutting edge of the cutting blade 21 are located on the same plane.

[0047] The control unit 100 also controls each component of the cutting device 1 to cause the cutting device 1 to perform a machining operation on either of the workpieces 200-1, 200-2. The control unit 100 is a computer having an arithmetic processing device with a microprocessor such as a CPU (central processing unit), a storage device with memory such as a ROM (read only memory) or RAM (random access memory), and an input / output interface device. The arithmetic processing device of the control unit 100 performs arithmetic processing in accordance with a computer program stored in the storage device, and outputs control signals for controlling the cutting device 1 to each component of the cutting device 1 via the input / output interface device.

[0048] The control unit 100 is connected to a display unit configured with a liquid crystal display device or the like that displays the status of the machining operation, images, etc., and an input unit that the operator uses to register machining content information, etc. The input unit is configured with a touch panel provided on the display unit.

[0049] (Machining operation) Next, the processing operation of the cutting device 1 will be described. Fig. 4 is a side view, partially in section, showing the cutting device shown in Fig. 1 cutting a thin workpiece. Fig. 5 is a side view, partially in section, showing the cutting device shown in Fig. 1 cutting a thick workpiece. Fig. 6 is a side view, partially in section, showing the cutting device shown in Fig. 5 dressing.

[0050] When starting the machining operation of the cutting device 1, the operator registers the machining conditions in the control unit 100, the control unit 100 accepts the machining conditions, and places one of the workpieces 200-1, 200-2 before cutting on the holding surface 111 of the main chuck table 11, and places the dress board 210 on the dress board holding surface 121 of the sub-chuck table 12. Thereafter, the cutting device 1 starts the machining operation when the control unit 100 accepts an instruction to start the machining operation from the operator. When starting the machining operation, the cutting device 1 suction-holds one of the workpieces 200-1, 200-2 on the holding surface 111 of the main chuck table 11, and suction-holds the dress board 210 on the dress board holding surface 121 of the sub-chuck table 12.

[0051] 4 and 5, in the cutting device 1, the sub-chuck table lifting unit 13 positions the dress board holding surface 121 of the sub-chuck table 12 at the retracted position. In the cutting device 1, the X-axis moving unit 41 moves the chuck table 10 toward the processing area, the microscope 30 photographs one of the workpieces 200-1, 200-2, and performs alignment based on the image photographed by the microscope 30. The cutting device 1 moves the main chuck table 11 and the cutting unit 20 relatively, and cuts one of the workpieces 200-1, 200-2 with the cutting blade 21 while supplying cutting water from the cutting water nozzle 24.

[0052] During the processing operation, when the cutting device 1 completes the cutting processing of either the workpiece 200-1, 200-2, it moves the chuck table 10 toward the loading / unloading area, stops the suction holding of the holding surface 111 in the loading / unloading area, and ends the processing operation.

[0053] Furthermore, the cutting device 1 performs dressing at a predetermined timing during the machining operation (for example, every time a predetermined number of workpieces 200-1, 200-2 are cut). For example, when a thick workpiece 200-1 is held on the holding surface 111 of the main chuck table 11, the cutting device 1 causes the sub-chuck table lifting unit 13 to position the dress board holding surface 121 of the sub-chuck table 12 at the dressing position. As shown in FIG. 6, the cutting device 1 dresses the dress board 210 by cutting the cutting edge of the cutting blade 21 into the dress board 210 based on the machining conditions.

[0054] In the first embodiment, when dressing is performed, if the thin workpiece 200-2 is held on the holding surface 111 of the main chuck table 11, the cutting device 1 positions the dress board holding surface 121 of the sub chuck table 12 at the dressing position using the sub chuck table lifting / lowering unit 13, and then performs dressing. However, in the present invention, when dressing is performed, if the thin workpiece 200-2 is held on the holding surface 111 of the main chuck table 11, the cutting device 1 may position the dress board holding surface 121 of the sub chuck table 12 at the retracted position using the sub chuck table lifting / lowering unit 13, and then perform dressing.

[0055] As described above, the cutting device 1 of embodiment 1 can change the height of the dress board holding surface 121 of the sub-chuck table 12 in the Z-axis direction using the sub-chuck table lifting unit 13.Therefore, when dressing the cutting blade 21, by positioning the dress board holding surface 121 at a dressing position at the same height as the upper surface of the thick workpiece 200-1, it is possible to prevent the microscope 30 from colliding with the thick workpiece 200-1 held on the main chuck table 11.

[0056] As a result, the cutting device 1 of embodiment 1 has the effect of preventing the microscope 30 from colliding with the workpieces 200-1, 200-2 held on the main chuck table 11 of the chuck table 10 when dressing the cutting blade 21.

[0057] Furthermore, when cutting either of the workpieces 200-1, 200-2, the cutting device 1 of embodiment 1 positions the dress board holding surface 121 of the sub-chuck table 12 in a retracted position, thereby preventing the cutting blade 21 from colliding with the dress board 210.

[0058] [Embodiment 2] A cutting device 1 according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a perspective view showing an example of the configuration of a sub-chuck table positioned at a dressing position of the cutting device according to the second embodiment. FIG. 8 is a perspective view showing a state in which the sub-chuck table shown in FIG. 7 is positioned at a retracted position. FIG. 9 is a side view, partially in cross section, showing a state in which the cutting device according to the second embodiment cuts a thick workpiece. FIG. 10 is a side view, partially in cross section, showing a state in which the cutting device shown in FIG. 9 is dressing. In FIGS. 7, 8, 9, and 10, the same parts as those in the first embodiment are designated by the same reference numerals, and description thereof will be omitted.

[0059] The cutting device 1 of embodiment 2 is the same as embodiment 1 except that the sub-chuck table lifting unit 13-2 is a motor that rotates the holding member 14 along with the orientation adjustment mechanism 15 so that the dress board holding surface 121 moves from the dressing position shown in FIG. 7 where the dress board holding surface 121 faces upward to the retracted position shown in FIG. 8 where the dress board holding surface 121 faces sideways, and that the sub-chuck table 12 is equipped with a protective film 17 shown in FIG. 8.

[0060] 7 and 8, the sub-chuck table lifting unit 13-2 is provided with an output shaft 133 that is installed on the table cover 4 and rotates about an axis parallel to the Y-axis direction, and a rotating arm 134 that is fixed to the output shaft 133 and the holding member 14 of the orientation adjustment mechanism 15. In the second embodiment, the sub-chuck table lifting unit 13 rotates the output shaft 133 about its axis to rotate the rotating arm 134 and move the dress board holding surface 121 between a dressing position where the dress board holding surface 121 faces upward and a retracted position where the dress board holding surface 121 faces sideways, thereby changing the height of the dress board holding surface 121 in the Z-axis direction.

[0061] In the second embodiment, the protective film 17 of the sub-chuck table 12 is made of a flexible resin and is formed into a film shape. One end of the protective film 17 is attached to the support member 151 of the orientation adjustment mechanism 15, and when the dress board holding surface 121 is positioned at the retracted position, as shown in FIG. 8, the protective film 17 covers the upper side of the sub-chuck table lifting / lowering unit 13-2.

[0062] In the second embodiment, the cover 16 is formed in a flat plate shape that covers the outer periphery of the sub-chuck table lifting / lowering unit 13-2.

[0063] In the cutting operation, when cutting either of the workpieces 200-1 and 200-2, the cutting device 1 according to the second embodiment positions the dress board holding surface 121 at the retracted position as shown in FIG. 9. Note that FIG. 9 shows an example in which the thick workpiece 200-1 is held on the holding surface 111, and an example in which the thin workpiece 200-2 is held on the holding surface 111 is omitted. In addition, when dressing is performed in the cutting operation, the cutting device 1 according to the second embodiment positions the dress board holding surface 121 at the dressing position as shown in FIG. 10. Note that FIG. 10 representatively shows an example in which the thick workpiece 200-1 is held on the holding surface 111, and in the second embodiment, the dress board holding surface 121 is also positioned at the dressing position when the thin workpiece 200-2 is held on the holding surface 111.

[0064] The cutting device 1 of embodiment 2 can change the height in the Z-axis direction of the dressing board holding surface 121 of the sub-chuck table 12 using the sub-chuck table lifting unit 13-2, so by positioning the dressing board holding surface 121 at the dressing position when dressing the cutting blade 21, similar to embodiment 1, it is possible to prevent the microscope 30 from colliding with the workpieces 200-1, 200-2 held on the main chuck table 11 of the chuck table 10 when dressing the cutting blade 21.

[0065] The present invention is not limited to the above-described embodiment. That is, various modifications can be made without departing from the gist of the present invention. For example, even if the thickness of the workpiece 200 is not greater than a predetermined value, and a thin workpiece 200-2 fixed using a thick fixture is held on the main chuck table 11 via the fixture, the height of the surface of the workpiece 200-2 will be greater than the predetermined height described above, and the present invention will achieve the same effect. [Explanation of symbols]

[0066] 1 Cutting equipment 10 Chuck table 11 Main chuck table 12 Sub-chuck table 13,13-2 Sub-chuck table lifting unit 20 Cutting unit 21 Cutting blade 40 Mobile Units 111 Holding surface 121 Dress board holding surface 200-1 Thick workpieces (workpieces with a specified thickness or more) 200-2 Thin workpiece (workpiece) 210 Dress board (workpiece)

Claims

[Claim 1] A cutting device comprising: a chuck table that holds a workpiece on a holding surface; a cutting unit that cuts the workpiece held by the chuck table with a cutting blade; and a moving unit that moves the chuck table relative to the cutting unit, The chuck table is a main chuck table for holding the workpiece; a sub-chuck table adjacent to the main chuck table and configured to hold a dress board used for dressing the cutting blade on a dress board holding surface; The sub-chuck table is a sub-chuck table lifting unit for changing the height of the dressing board holding surface between a dressing position corresponding to the height of the upper surface of the workpiece held by the main chuck table, the upper surface being at a height equal to or higher than a predetermined height, and a retreat position lower than the dressing position; The sub-chuck table lifting unit rotates the dress board holding surface from an upward direction to a horizontal direction, and moves the dress board from the dressing position to the retracted position.

Images