Cutting method for workpiece

Abstract

To provide a workpiece cutting method capable of suppressing occurrence of uneven wear of a cutting blade.SOLUTION: A workpiece cutting method relatively moves along outer periphery of workpiece while relatively reciprocating a cutting blade and the workpiece in a direction at which a spindle extends, in a state where a cutting blade of the cutting blade rotated together with the spindle is cut into the upper side of an outer peripheral region of the workpiece, and thereby cuts the upper side of an outer peripheral region of the workpiece. In this case, one side (for example, radial outside of disk-like workpiece) in a direction at which the spindle of the cutting blade extends, and the other side (for example, radial inside of disk-like workpiece) in a direction at which the spindle of the cutting blade extends are worn at a similar degree. Therefore, occurrence of uneven wear of the cutting blade can be suppressed.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a method for cutting a workpiece by using a cutting blade to cut the upper side of the outer peripheral region of the workpiece. [Background technology]

[0002] Chips, such as IC (Integrated Circuit) and LSI (Large Scale Integration) devices, are essential components in various electronic devices, such as mobile phones and personal computers. These chips are manufactured, for example, by forming a large number of devices on the surface of a workpiece, such as a wafer made of semiconductor material, and then dividing the workpiece into regions containing individual devices.

[0003] In the workpieces used in chip manufacturing, cracks are likely to occur in the peripheral region where stress is concentrated. Therefore, in the chip manufacturing process, the peripheral region is generally chamfered prior to various processes. Furthermore, in the chip manufacturing process, in order to miniaturize the manufactured chips, the back side of the workpiece is often ground to thin the workpiece prior to dividing it.

[0004] However, when the backside of a workpiece with a chamfered peripheral region is ground to thin the workpiece, the backside of the peripheral region takes on a knife-edge shape. Stress tends to concentrate in this area, making it prone to cracks. Therefore, in the chip manufacturing process, after edge trimming is performed to cut the front side of the peripheral region of the workpiece, the backside of the workpiece is sometimes ground to remove the remaining portion of the peripheral region (see, for example, Patent Document 1).

[0005] Edge trimming of a workpiece is generally performed using a cutting blade with a cutting edge that is thicker than the width of the outer peripheral region of the workpiece. For example, Patent Document 1 discloses that the outer peripheral region of a disk-shaped workpiece is cut by rotating the workpiece while the cutting edge of the rotating cutting blade is cut into the outer peripheral region of the workpiece (see claim 3, etc.).

[0006] Furthermore, edge trimming of a workpiece may be performed using a cutting blade having a cutting edge thinner than the width of the outer peripheral region of the workpiece. For example, Patent Document 1 discloses that the cutting edge of a rotating cutting blade is inserted into the surface side of the outer peripheral region of a disk-shaped workpiece, and the cutting edge is moved radially outward while the workpiece is rotated, thereby cutting the surface side of the outer peripheral region of the workpiece (see claim 4, etc.). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-173961 Summary of the Invention [Problem to be solved by the invention]

[0008] When edge trimming of a workpiece is performed using a cutting blade with a cutting edge that is thicker than the width of the outer peripheral region of the workpiece, part of the outer surface of the cutting blade comes into contact with the workpiece, while the remainder does not, resulting in uneven wear of the cutting blade (uneven wear). Also, even when edge trimming of a workpiece is performed using a cutting blade with a cutting edge that is thinner than the width of the outer peripheral region of the workpiece, wear on the cutting blade's traveling direction side (the radially outer side of the workpiece) becomes significant, which may result in uneven wear of the cutting blade.

[0009] Therefore, cutting blades are often subjected to a process (dressing) in which the outer peripheral region of the cutting edge is ground at appropriate times to make the outer surface generally flat. This dressing is performed, for example, by bringing the cutting edge of the rotating cutting blade into contact with a dressing board on which abrasive grains are dispersed. However, when performing such dressing, there is a risk that the productivity of chips produced by dividing the workpiece will decrease.

[0010] In view of this, an object of the present invention is to provide a method for cutting a workpiece that can suppress the occurrence of uneven wear of the cutting blade. [Means for solving the problem]

[0011] The present invention One aspect of According to the present invention, there is provided a method for cutting a workpiece by using a cutting blade that has a cutting edge thinner than the width of the outer peripheral region of the workpiece and is attached to the tip of a rotatable spindle, the method comprising: a holding step of holding the workpiece in a state where the upper surface of the workpiece is exposed; a groove forming step of forming a groove in the boundary region by relatively moving the cutting blade and the workpiece along the outer periphery of the workpiece after the holding step, with the cutting edge of the cutting blade rotating together with the spindle cutting into an upper side of a boundary region including an inner edge of the outer periphery region of the workpiece; Applicable groove formation and a cutting step in which, after the step, the cutting edge of the cutting blade rotating with the spindle cuts into the upper side of the outer peripheral region of the workpiece, the cutting blade and the workpiece are moved relatively back and forth along the direction in which the spindle extends, while the cutting edge is moved relatively along the outer periphery of the workpiece.

[0012] moreover, The workpiece is disk-shaped, and the relative movement between the cutting blade and the workpiece along the outer periphery of the workpiece in the cutting step is performed by rotating the workpiece. It is preferable.

[0013] Also, The workpiece has a polygonal columnar shape, and the relative movement between the cutting blade and the workpiece along the outer periphery of the workpiece in the cutting step causes the cutting blade and the workpiece to move relatively along a direction perpendicular to the direction in which the spindle extends. It is preferable.

[0014] According to another aspect of the present invention, there is provided a method for cutting a workpiece using a cutting blade having a cutting edge thinner than the width of the outer circumferential region of the workpiece and attached to the tip of a rotatable spindle, the method comprising: a holding step for holding the workpiece with the top surface of the workpiece exposed; and a cutting step for cutting the upper side of the outer circumferential region of the workpiece after the holding step by relatively moving the cutting blade and the workpiece along the periphery of the workpiece while moving the cutting blade and the workpiece back and forth relative to each other in the direction in which the spindle extends, with the cutting edge of the cutting blade rotating with the spindle cutting into the upper side of the outer circumferential region of the workpiece; wherein the workpiece has a polygonal pillar shape, and the relative movement between the cutting blade and the workpiece along the periphery of the workpiece in the cutting step is performed by relatively moving the cutting blade and the workpiece along a direction perpendicular to the direction in which the spindle extends.

[0015] Furthermore, the cutting step preferably includes a first cutting step in which the cutting blade and the workpiece are moved relatively back and forth along the direction in which the spindle extends, while the cutting edge of the cutting blade, which rotates with the spindle, has cut into the workpiece from the top surface to a first depth, thereby cutting a portion of the outer circumferential region of the workpiece that is located from the top surface to the first depth; and a second cutting step after the first cutting step in which the cutting blade and the workpiece are moved relatively back and forth along the direction in which the spindle extends, while the cutting edge of the cutting blade, which rotates with the spindle, has cut into the workpiece to a second depth deeper than the first depth, thereby cutting a portion of the outer circumferential region of the workpiece that is located between the first depth and the second depth. [Effects of the Invention]

[0016] In the present invention, the cutting edge of the cutting blade rotating with the spindle cuts into the upper side of the outer peripheral region of the workpiece, and the cutting blade and the workpiece are moved back and forth relative to each other along the direction in which the spindle extends, thereby cutting the upper side of the outer peripheral region of the workpiece.

[0017] In this case, one side of the cutting blade in the direction in which the spindle extends (e.g., the radially outer side of the disk-shaped workpiece) and the other side of the cutting blade in the direction in which the spindle extends (e.g., the radially inner side of the disk-shaped workpiece) wear to the same extent. Therefore, in the present invention, it is possible to suppress uneven wear of the cutting blade. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a perspective view schematically illustrating an example of a cutting device. [Figure 2] FIG. 2(A) is a top view that schematically shows an example of a workpiece, and FIG. 2(B) is a cross-sectional view that schematically shows an example of a workpiece. [Figure 3] FIG. 3 is a front view schematically showing some of the components of the cutting unit. [Figure 4] FIG. 4 is a flowchart schematically illustrating an example of a method for cutting a workpiece. [Figure 5] FIG. 5(A) is a top view that schematically shows the state of the cutting step, and FIG. 5(B) is a front view that schematically shows the state of the cutting step. [Figure 6] FIG. 6(A) is a top view that schematically shows the state of the cutting step, and FIG. 6(B) is a front view that schematically shows the state of the cutting step. [Figure 7] FIG. 7(A) is a top view that schematically shows the state of the cutting step, and each of FIG. 7(B) and FIG. 7(C) is a front view that schematically shows the state of the cutting step. [Figure 8]FIG. 8(A) is a top view schematically showing an example of a workpiece after the groove forming step, and FIG. 8(B) is a cross-sectional view schematically showing an example of a workpiece after the groove forming step. DETAILED DESCRIPTION OF THE INVENTION

[0019] An embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a perspective view showing a schematic diagram of an example of a cutting device. Note that the X-axis direction (front-rear direction) and the Y-axis direction (left-right direction) shown in Fig. 1 are directions perpendicular to each other on a horizontal plane, and the Z-axis direction (up-down direction) is a direction (vertical direction) perpendicular to the X-axis direction and the Y-axis direction.

[0020] 1 includes a base 4 that supports each of the components. A rectangular opening 4a whose longitudinal direction is parallel to the X-axis direction is formed on the top surface of the base 4. A flat cover 6 and a bellows-like cover 8 that expands and contracts as the cover 6 moves are exposed inside the opening 4a.

[0021] A disk-shaped holding table 10 is provided above the cover 6. The holding table 10 has a disk-shaped porous plate 10a exposed upward. The upper surface of the porous plate 10a is generally parallel to the workpiece and serves as the holding surface of the holding table 10 that holds the workpiece. An X-axis direction movement mechanism (not shown) that moves the cover 6 and holding table 10 along the X-axis direction is provided below the covers 6 and 8.

[0022] Fig. 2(A) is a top view showing an example of a workpiece held on the holding surface of the holding table 10, and Fig. 2(B) is a cross-sectional view showing the wafer. The workpiece 11 shown in Fig. 2(A) and Fig. 2(B) is a wafer made of a semiconductor material such as Si (silicon), SiC (silicon carbide), or GaN (gallium nitride).

[0023] The workpiece 11 is divided into a plurality of regions by dividing lines set in a grid pattern. A device 13 such as an IC or an LSI is formed on the surface (upper surface) 11a of each of the plurality of regions. In addition, a region (peripheral region) of the workpiece 11 having a predetermined width (e.g., 1.5 mm) around its outer periphery is chamfered. In other words, the side surface 11b of the workpiece 11 is curved so as to be convex outward.

[0024] The back surface (lower surface) 11c of the workpiece 11 is placed on the holding surface (upper surface of the porous plate 10a) of the holding table 10 shown in Fig. 1, either directly or via a dicing tape (not shown). Furthermore, the lower surface side of the porous plate 10a is connected to a suction source (not shown), such as an ejector, via a suction path formed inside the holding table 10.

[0025] Therefore, when the suction source is operated with the workpiece 11 placed on the holding surface, the workpiece 11 is sucked and held on the holding table 10. Furthermore, the holding table 10 is connected to a rotation drive source (not shown) such as a motor. When the rotation drive source is operated, the holding table 10 rotates around a rotation axis that passes through the center of the holding surface and is aligned with the Z-axis direction.

[0026] A support structure 12 is provided near the opening 4a on the top surface of the base 4. This support structure 12 has an erected portion 12a extending along the Z-axis direction from the top surface of the base 4, and an arm portion 12b extending along the Y-axis direction from the upper end of the erected portion 12a so as to cross over the opening 4a. A Y-axis direction movement mechanism 14 is provided on the front side of the arm portion 12b.

[0027] The Y-axis direction movement mechanism 14 is fixed to the front surface of the arm portion 12b and includes a pair of Y-axis guide rails 16 extending along the Y-axis direction. A Y-axis movement plate 18 is connected to the front surfaces of the pair of Y-axis guide rails 16 in a manner that allows it to slide along the pair of Y-axis guide rails 16.

[0028] A screw shaft 20 extending along the Y-axis direction is disposed between the pair of Y-axis guide rails 16. A motor (not shown) for rotating the screw shaft 20 is connected to one end of the screw shaft 20. A nut portion (not shown) for accommodating balls that roll on the surface of the rotating screw shaft 20 is provided on the surface of the screw shaft 20 on which a spiral groove is formed, thereby forming a ball screw.

[0029] That is, when the screw shaft 20 rotates, the balls circulate inside the nut portion, causing the nut portion to move along the Y-axis direction. The nut portion is fixed to the rear surface side of the Y-axis moving plate 18. Therefore, when the screw shaft 20 is rotated by a motor connected to one end of the screw shaft 20, the Y-axis moving plate 18 moves along the Y-axis direction together with the nut portion.

[0030] A Z-axis direction moving mechanism 22 is provided on the front side of the Y-axis moving plate 18. This Z-axis direction moving mechanism 22 is fixed to the front side of the Y-axis moving plate 18 and includes a pair of Z-axis guide rails 24 that extend along the Z-axis direction. A Z-axis moving plate 26 is connected to the front side of the pair of Z-axis guide rails 24 in a manner that allows it to slide along the pair of Z-axis guide rails 24.

[0031] A screw shaft 28 extending along the Z-axis direction is disposed between the pair of Z-axis guide rails 24. A motor 30 for rotating the screw shaft 28 is connected to one end of the screw shaft 28. A nut portion (not shown) for accommodating balls that roll on the surface of the rotating screw shaft 28 is provided on the surface of the screw shaft 28 on which a spiral groove is formed, thereby constituting a ball screw.

[0032] That is, when the screw shaft 28 rotates, the balls circulate inside the nut portion, causing the nut portion to move along the Z-axis direction. The nut portion is fixed to the rear surface side of the Z-axis moving plate 26. Therefore, when the screw shaft 28 is rotated by the motor 30, the Z-axis moving plate 26 moves along the Z-axis direction together with the nut portion.

[0033] A cylindrical housing 32 is fixed to the lower part of the Z-axis moving plate 26. A cutting unit 34 is housed inside the housing 32. However, some of the components of the cutting unit 34 are exposed from the side surface of the housing 32 on the holding table 10 side.

[0034] 3 is a front view schematically showing the components of the cutting unit 34 that are exposed and not housed in the housing 32. The components of the cutting unit 34 shown in FIG. 3 are concentric structures centered on a straight line along the Y-axis direction. Therefore, FIG. 3 can also be expressed as a top view schematically showing the components of the cutting unit 34 that are exposed and not housed in the housing 32.

[0035] The cutting unit 34 has a spindle 36 that extends along the Y-axis direction and has a tip end that protrudes from the housing 32. The spindle 36 is supported by the housing 32 in a manner that allows it to rotate around a rotation axis that is parallel to the Y-axis direction.

[0036] A cutting blade 38 is attached to the tip of the spindle 36. This cutting blade 38 has an annular cutting edge 40 (for example, an annular cutting edge with a thickness of 0.5 mm) that is thinner than the width of the outer peripheral region of the workpiece 11. The cutting edge 40 includes abrasive grains fixed by a binder made of metal, ceramic, resin, or the like.

[0037] The base end of the spindle 36 is connected to a rotary drive source (not shown), such as a motor, built into the housing 32. When this rotary drive source is operated, the cutting blade 38 rotates together with the spindle around a rotation axis along the Y-axis direction.

[0038] 1, a cutting fluid supply unit 42 is provided around the tip of the spindle 36. For example, when the cutting edge 40 of the rotating cutting blade 38 cuts the upper side of the outer peripheral region of the workpiece 11, this cutting fluid supply unit 42 supplies cutting fluid (e.g., water) to the processing point (the contact interface between the cutting edge 40 and the workpiece 11) to wash away cutting chips and suppress heating of the cutting edge 40 and the workpiece 11.

[0039] Furthermore, an imaging unit 44 is provided at a position adjacent to the cutting unit 34 in the X-axis direction and fixed to the lower part of the Z-axis moving plate 26. This imaging unit 44 includes, for example, a light source such as an LED (Light Emitting Diode), an objective lens, and an imaging element such as a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor.

[0040] 4 is a flowchart schematically illustrating an example of a method for cutting a workpiece 11 by cutting the upper side of the outer peripheral region of the workpiece 11 in the cutting device 2. In this method, first, the workpiece 11 is held in a state in which the upper surface of the workpiece 11 is exposed (holding step: S1).

[0041] Specifically, the workpiece 11 is placed on the holding table 10 so that the center of the back surface (lower surface) 11c of the workpiece 11 overlaps with the center of the holding surface of the holding table 10 and the front surface (upper surface) 11a of the workpiece 11 is exposed, and then the suction source connected to the porous plate 10a is operated.

[0042] Next, with the cutting edge of the rotating cutting blade 38 cutting into the upper side of the outer peripheral region of the workpiece 11, the cutting blade 38 is moved back and forth along the Y-axis direction while rotating the workpiece 11, thereby cutting the upper side of the outer peripheral region of the workpiece 11 (cutting step: S2).

[0043] Each of Figures 5(A), 6(A) and 7(A) is a top view showing the cutting step (S2) in a schematic manner, and each of Figures 5(B), 6(B) and 7(B) and 7(C) is a front view showing the cutting step (S2) in a schematic manner.

[0044] In this cutting step (S2), first, the cutting edge 40 of the cutting blade 38 is positioned directly above the inner end of the outer peripheral region located in the Y-axis direction when viewed from the center of the surface 11a of the workpiece 11. Specifically, the X-axis direction moving mechanism adjusts the position of the holding table 10, and the Y-axis direction moving mechanism 14 adjusts the position of the cutting blade 38 so that the cutting edge 40 is positioned at this position (see FIGS. 5(A) and 5(B)).

[0045] Next, while rotating the cutting blade 38, the cutting edge 40 is caused to cut into the upper side of the outer peripheral region of the workpiece 11. Specifically, while a rotary drive source connected to the base end of the spindle 36 rotates the cutting blade 38 together with the spindle 36, the Z-axis movement mechanism 22 lowers the cutting blade 38 until the lower end of the cutting edge 40 reaches a desired depth (e.g., 200 μm) from the surface 11a of the workpiece 11 (see FIGS. 6(A) and 6(B)).

[0046] Next, without stopping the rotation of the cutting blade 38, the cutting blade 38 is moved back and forth along the Y-axis direction while rotating the workpiece 11. Specifically, while the Y-axis direction moving mechanism 14 moves the cutting blade 38 back and forth, the rotary drive source connected to the holding table 10 rotates the holding table 10 that holds the workpiece 11 (see FIGS. 7(A), 7(B), and 7(C)).

[0047] As a result, the workpiece 11 is cut along the outer periphery of the workpiece 11, forming a step 11d in the outer peripheral region. Note that the reciprocating movement of the cutting blade 38 along the Y-axis direction here refers to the repetition of the movement of the cutting blade 38 radially outward of the workpiece 11 until the lower end of the cutting edge 40 reaches from the inner edge to the outer edge of the outer peripheral region of the workpiece 11 (see FIG. 7(B)), and the movement of the cutting blade 38 radially inward of the workpiece 11 until the lower end of the cutting edge 40 reaches from the outer edge to the inner edge of the outer peripheral region of the workpiece 11 (see FIG. 7(C)).

[0048] For example, if the width of the outer peripheral region of the workpiece 11 is 1.5 mm and the thickness of the cutting edge 40 of the cutting blade 38 is 0.5 mm, the cutting blade 38 is moved back and forth at 1 mm / sec while the workpiece 11 is rotated at 3° / sec. In this case, Fig. 7(A) shows the situation 30 seconds after the cutting blade 38 starts to move back and forth and the workpiece 11 starts to rotate. In this case, cutting of the upper part of the outer peripheral region of the workpiece 11 is completed 120 seconds after the cutting blade 38 starts to move back and forth and the workpiece 11 starts to rotate.

[0049] In the method for cutting a workpiece shown in Figure 4, the cutting edge 40 of the cutting blade 38, which rotates together with the spindle 36, cuts into the upper side of the outer peripheral region of the workpiece 11, and the cutting blade 38 is moved back and forth along the Y-axis direction while the workpiece 11 is rotated, thereby cutting the upper side of the outer peripheral region of the workpiece 11.

[0050] In this case, one side of the cutting blade 40 in the Y-axis direction (for example, the radially outer side of the disk-shaped workpiece 11) and the other side of the cutting blade 40 in the Y-axis direction (for example, the radially inner side of the disk-shaped workpiece 11) are worn to the same extent. Therefore, in the method for cutting a workpiece shown in FIG. 4, uneven wear of the cutting blade 40 can be suppressed.

[0051] The above-described method is one aspect of the present invention, and the present invention also includes content different from the above-described method. For example, the cutting device 2 may be provided with a Y-axis direction movement mechanism that moves the holding table 10 along the Y-axis direction, a Z-axis direction movement mechanism that moves the holding table 10 along the Z-axis direction, and / or a rotation mechanism that rotates the cutting blade 38 around the holding table 10 in a plan view. In other words, in the present invention, it is sufficient to provide components for moving the holding table 10 and the cutting blade 38 relative to each other, and there are no limitations on the specific structure.

[0052] Furthermore, in the present invention, cutting of the upper side of the outer peripheral edge of the workpiece 11 may be performed in stages in order to suppress wear of the cutting blade 40. For example, when cutting the upper side of the outer peripheral edge of the workpiece 11 to a depth of 200 μm from the surface 11a of the workpiece 11, cutting of the upper side of the outer peripheral edge of the workpiece 11 may be performed every 50 μm in depth.

[0053] That is, the cutting step of the present invention may include a first cutting step for cutting a portion of the outer peripheral region of the workpiece 11 that exists up to a depth of 50 μm from the surface (top surface) 11a of the workpiece 11, a second cutting step for cutting a portion of the outer peripheral region of the workpiece 11 that exists at a depth of 50 μm to 100 μm after the first cutting step, a third cutting step for cutting a portion of the outer peripheral region of the workpiece 11 that exists at a depth of 100 μm to 150 μm after the second cutting step, and a fourth cutting step for cutting a portion of the outer peripheral region of the workpiece 11 that exists at a depth of 150 μm to 200 μm after the third cutting step.

[0054] For example, in each of the first to fourth cutting steps, the cutting edge 40 of the cutting blade 38, which rotates together with the spindle 36, cuts into the surface (top surface) 11a of the workpiece 11 to a predetermined depth (50 μm, 100 μm, 150 μm, or 200 μm), and the cutting blade 38 is moved back and forth along the Y-axis direction while rotating the workpiece 11, thereby cutting a portion of the outer peripheral region of the workpiece 11 that is within a predetermined depth range (surface (top surface) 11a to a depth of 50 μm, a depth of 50 μm to a depth of 100 μm, a depth of 100 μm to a depth of 150 μm, or a depth of 150 μm to a depth of 200 μm).

[0055] In the cutting step of the present invention, the upper side of the outer peripheral edge of the workpiece 11 may be cut while the cutting blade 38 is lowered. In this case, for example, the cutting blade 38 may be moved back and forth at 1 mm / sec while the workpiece 11 is rotated at 30° / sec, and the cutting blade 38 may be lowered by 5 μm for each rotation (12 seconds) of the workpiece 11.

[0056] Furthermore, in the present invention, a groove forming step may be performed between the holding step and the cutting step, in which a groove is formed on the upper side (surface 11a side) of a region (boundary region) including the inner edge of the outer peripheral region of the workpiece 11. This groove forming step is performed, for example, in the cutting device 2, by rotating the workpiece 11 with the cutting edge 40 of the cutting blade 38 rotating together with the spindle 36 cutting into the upper side of the boundary region of the workpiece 11.

[0057] 8(A) is a top view of the workpiece 11 after the groove forming step, and FIG. 8(B) is a cross-sectional view of the workpiece 11 after the groove forming step. When a groove 10e is provided on the surface 11a side of the boundary region of the workpiece 11 prior to the cutting step of the present invention, cutting chips washed away by the cutting fluid in the cutting step are less likely to enter inside the groove 10e. In other words, in this case, the likelihood of cutting chips getting into the device 13 formed on the surface 11a of the workpiece 11 can be reduced.

[0058] Furthermore, in the present invention, the shape of the workpiece whose upper outer periphery is to be cut is not limited to a disk. For example, in the present invention, the upper outer periphery of a polygonal prism (e.g., a square prism) made of glass may be cut. In this case, the present invention is implemented in a cutting device 2 in which the holding table 10 is replaced with a holding table having a rectangular holding surface.

[0059] In this case, in the cutting step of the present invention, the cutting edge 40 of the cutting blade 38 rotating together with the spindle 36 cuts into the upper side of the outer peripheral region of the workpiece, and the cutting blade 38 is moved back and forth along the Y-axis direction while the workpiece 11 is moved along the X-axis direction, thereby cutting the upper side of the outer peripheral region of the workpiece.

[0060] That is, in this case, the cutting step of the present invention is carried out by repeating a rotation step of rotating the holding table that holds the workpiece so that one of the multiple side surfaces of the workpiece is parallel to the X-axis direction, and a side cutting step of cutting a portion of the outer peripheral region of the workpiece that includes the side surface that is parallel to the X-axis direction.

[0061] In addition, the structures and methods according to the above-described embodiments can be modified as appropriate without departing from the scope of the present invention. [Explanation of symbols]

[0062] 2:Cutting device 4: Base (4a: opening) 6,8:Cover 10: Holding table (10a: Porous plate) 11: Workpiece (11a: Front surface (top surface), 11b: Side surface, 11c: Back surface (bottom surface)) (11d: step, 11e: groove) 12: Support structure (12a: standing part, 12b: arm part) 13: Device 14:Y-axis direction movement mechanism 16: Y-axis guide rail 18: Y-axis moving plate 20: Screw shaft 22:Z-axis direction movement mechanism 24: Z-axis guide rail 26: Z-axis moving plate 28: Screw shaft 30: Motor 32: Housing 34: Cutting unit 36: Spindle 38: Cutting blade 40: Cutting blade 42: Cutting fluid supply unit 44: Imaging unit

Claims

1. A method for cutting a workpiece, in which an upper side of an outer peripheral region of the workpiece is cut using a cutting blade that has a cutting edge thinner than the width of the outer peripheral region and is attached to the tip of a rotatable spindle, a holding step of holding the workpiece in a state where the top surface of the workpiece is exposed; a groove forming step of forming a groove in the boundary region by relatively moving the cutting blade and the workpiece along the outer periphery of the workpiece after the holding step, with the cutting edge of the cutting blade rotating together with the spindle cutting into an upper side of a boundary region including an inner edge of the outer periphery region of the workpiece; a cutting step after the groove forming step, in which the cutting edge of the cutting blade rotating together with the spindle cuts into the upper side of the outer peripheral region of the workpiece, by relatively moving the cutting blade and the workpiece along the outer periphery of the workpiece while relatively reciprocating along the extending direction of the spindle; A method for cutting a workpiece, comprising:

2. The workpiece is disk-shaped, 2. The method for cutting a workpiece according to claim 1, wherein the relative movement of the cutting blade and the workpiece along the outer periphery of the workpiece in the cutting step is performed by rotating the workpiece.

3. The workpiece has a polygonal prism shape, 2. The method for cutting a workpiece according to claim 1, wherein the relative movement of the cutting blade and the workpiece along the outer periphery of the workpiece in the cutting step is performed by moving the cutting blade and the workpiece relative to each other in a direction perpendicular to the direction in which the spindle extends.

4. A method for cutting a workpiece, in which an upper side of an outer peripheral region of the workpiece is cut using a cutting blade having a cutting edge thinner than the width of the outer peripheral region and attached to the tip of a rotatable spindle, comprising: a holding step of holding the workpiece in a state where the top surface of the workpiece is exposed; a cutting step in which, after the holding step, the cutting blade and the workpiece are moved relatively along the periphery of the workpiece while moving back and forth relative to each other in the direction in which the spindle extends, with the cutting edge of the cutting blade rotating together with the spindle cutting into the upper side of the outer periphery of the workpiece, thereby cutting the upper side of the outer periphery of the workpiece, The workpiece has a polygonal prism shape, A method for cutting a workpiece, in which the relative movement between the cutting blade and the workpiece along the outer periphery of the workpiece in the cutting step is performed by relatively moving the cutting blade and the workpiece along a direction perpendicular to the direction in which the spindle extends.

5. The cutting step includes: a first cutting step in which, with the cutting edge of the cutting blade rotating together with the spindle cutting into the workpiece from the top surface to a first depth, the cutting blade and the workpiece are moved relatively back and forth along the direction in which the spindle extends while being moved relatively along the outer periphery of the workpiece, thereby cutting a portion of the outer periphery region of the workpiece that is present from the top surface of the workpiece to the first depth; a second cutting step after the first cutting step, in which the cutting blade and the workpiece are moved relatively along the outer periphery of the workpiece while moving back and forth relative to each other along the direction in which the spindle extends, with the cutting edge of the cutting blade rotating together with the spindle cutting to a second depth deeper than the first depth, thereby cutting a portion of the outer periphery region of the workpiece that exists between the first depth and the second depth; 5. The method for cutting a workpiece according to claim 1, further comprising:

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