Dressing method

Abstract

To provide a dressing method in which a dressing board can be used efficiently.SOLUTION: In a dressing method, a cutting edge of a cutting blade is subjected to dressing while rotating not only a spindle having the cutting blade attached to a tip part thereof but also a chuck table holding a dressing board. This enables a whole area of the dressing board to be subjected to dressing so that thicknesses of the dressing board are reduced nearly equally. When the dressing method is applied in order to subject the cutting edge to dressing in plural times utilizing the dressing board, portions which can be subjected to dressing of the dressing board can be subjected to dressing thoroughly. This enables the dressing board to be efficiently used.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a dressing method for dressing a cutting blade in a cutting device that includes a chuck table that can rotate around a rotation axis that is a straight line that passes through the center of a holding surface and that is aligned along a first direction that is perpendicular to the holding surface, and a spindle that has a cutting blade with an annular cutting edge attached to its tip and that extends along a second direction that is perpendicular to the first direction. [Background technology]

[0002] Chips for devices such as integrated circuits (ICs) are essential components in various electronic devices such as mobile phones and personal computers. These chips are manufactured by dividing a workpiece, such as a wafer, on the surface of which multiple devices are provided, along the boundaries between the multiple 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 of the workpiece 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, thinning the workpiece in this way results in a knife-edge-like shape at its peripheral region, which is prone to stress concentration and cracking. Therefore, in the chip manufacturing process, the workpiece is first cut to remove the front side of the peripheral region of the workpiece, i.e., edge trimming, and then the workpiece is ground to remove the back side (remaining portion) of the peripheral region.

[0005] Edge trimming is generally performed using a cutting blade having an annular cutting edge whose outer circumferential surface width is greater than the width of the chamfered outer circumferential region of the workpiece. For example, edge trimming is performed by rotating the disc-shaped workpiece while the cutting edge of the rotating cutting blade is cutting into the outer circumferential region of the workpiece.

[0006] When edge trimming is performed in this manner, a portion of the cutting edge of the cutting blade located on one side in the direction along the width of the outer circumferential surface is used to cut the workpiece, while a portion located on the other side is not used to cut the workpiece. Therefore, when edge trimming using this cutting blade is repeated, only the portion located on one side is worn away, and the flatness of the outer circumferential surface of the cutting edge is impaired.

[0007] In consideration of these points, a dressing method for improving the flatness of the outer peripheral surface of the cutting edge of a cutting blade has been proposed (see, for example, Patent Document 1). Specifically, in this method, the cutting blade is dressed by rotating the cutting blade and moving the cutting blade in a direction along the width of the outer peripheral surface of the cutting blade so that the tip of the cutting blade comes into contact with a dressing board. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-588 Summary of the Invention [Problem to be solved by the invention]

[0009] As described above, when the cutting edge of a cutting blade is dressed, the linear portion of the dressing board used for dressing is removed to form a groove. When the cutting edge is dressed again using this dressing board, a portion of the dressing board sufficiently separated from the already formed groove is often used for dressing so that the outer peripheral surface of the cutting edge is accurately flattened.

[0010] In this case, when a plurality of mutually spaced grooves are formed across the entire area of ​​the dressing board, the dressing board becomes unusable. Therefore, the dressing board is discarded with a portion remaining between adjacent pairs of grooves that can be used for dressing. In view of this, an object of the present invention is to provide a dressing method that enables efficient use of the dressing board. [Means for solving the problem]

[0011] According to the present invention, in a cutting device including a chuck table rotatable about a rotation axis that passes through the center of a holding surface and is aligned along a first direction perpendicular to the holding surface, and a spindle having a cutting blade with an annular cutting edge attached to its tip and extending along a second direction perpendicular to the first direction, a dressing method for dressing the cutting edge includes a holding step of holding a dressing board on the holding surface of the chuck table, and a step of holding a dressing board such that the tip of the cutting edge is positioned between one end and the other end of the dressing board in the first direction and perpendicular to the first direction. A dressing method is provided which includes a positioning step of adjusting the relative position of the chuck table and the spindle so that the chuck table is positioned between one end and the other end of the dressing board in the third direction and is spaced apart from the dressing board in a fourth direction perpendicular to both the first direction and the third direction, and a dressing step of moving the chuck table and the spindle relatively along the fourth direction while rotating both the chuck table and the spindle so that the tip of the cutting blade comes into contact with the dressing board.

[0012] Preferably, the third direction is the same direction as the second direction. Furthermore, in the positioning step, it is preferable that the tip of the cutting blade is positioned at the same position as the center of the holding surface of the chuck table in the third direction. [Effects of the Invention]

[0013] In the dressing method of the present invention, the cutting edge of the cutting blade is dressed while rotating not only the spindle to which the cutting blade is attached at its tip but also the chuck table that holds the dressing board, so that the entire area of ​​the dressing board can be dressed so that the thickness of the dressing board is reduced approximately evenly.

[0014] By applying the dressing method of the present invention to each of the multiple dressings of the cutting blade using the dressing board, it is possible to dress all of the parts of the dressing board that can be used for dressing, i.e., in this case, it is possible to use the dressing board efficiently. [Brief explanation of the drawings]

[0015] [Figure 1] Figure 1(A) is an oblique view schematically showing an example of a frame unit including a dressing board, and Figure 1(B) is a cross-sectional view schematically showing the frame unit shown in Figure 1(A). [Figure 2] FIG. 2 is a perspective view schematically illustrating an example of a cutting device. [Figure 3] FIG. 3 is a plan view schematically showing some components of a cutting unit included in the cutting device shown in FIG. [Figure 4] FIG. 4 is a flow chart that schematically shows an example of a dressing method for dressing the cutting edge of the cutting blade included in the cutting unit shown in FIG. [Figure 5] FIG. 5 is a partial cross-sectional side view that schematically shows the state of the holding step S1 shown in FIG. [Figure 6] FIG. 6(A) is a plan view that schematically shows the state of the positioning step S2 shown in FIG. 4, and FIG. 6(B) is a partially cross-sectional side view that schematically shows the state of the positioning step S2. [Figure 7] FIG. 7(A) is a plan view that schematically shows the state of the dressing step S3 shown in FIG. 4, and FIG. 7(B) is a partially cross-sectional side view that schematically shows the state of the dressing step S3. [Figure 8] Figures 8(A) and 8(B) are each a perspective view schematically showing an example of a frame unit including a dressing board different from the dressing board shown in Figures 1(A) and 1(B). [Figure 9] FIG. 9 is a flow chart that schematically shows an example of a dressing method that is different from the dressing method shown in FIG. [Figure 10] Figure 10(A) is a plan view schematically showing the positioning step S2' shown in Figure 9, and Figure 10(B) is a plan view schematically showing the dressing board after the dressing step S3 shown in Figure 9. [Figure 11] FIG. 11 is a flow chart that schematically shows an example of a dressing method that is different from the dressing method shown in FIG. 4 or FIG. [Figure 12] FIG. 12(A) is a plan view schematically showing the state of the positioning step S2'' shown in FIG. 11, and is a plan view schematically showing the state of the dressing step S3' shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0016] An embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1(A) is a perspective view showing an example of a frame unit including a dressing board, and Fig. 1(B) is a cross-sectional view showing the frame unit shown in Fig. 1(A). The frame unit 1 shown in Fig. 1(A) and Fig. 1(B) includes a disk-shaped dressing board 3 having a thickness of, for example, 0.5 mm to 1.5 mm.

[0017] This dressing board 3 is manufactured, for example, by mixing green carborundum (GC) abrasive grains made of silicon carbide (SiC) or white alundum (WA) abrasive grains made of aluminum oxide (Al2O3) with a binder made of vitrified bond or resin bond, and then firing the mixture.

[0018] In addition, the dressing board 3 has its back surface attached to the central region of a circular tape 5 having a diameter larger than that of the dressing board 3, so that its surface is exposed. This tape 5 has, for example, a flexible film-like base layer and an adhesive layer (glue layer) provided on one side of the base layer (the side facing the dressing board 3).

[0019] Specifically, the base layer is made of polyolefin (PO), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polystyrene (PS), etc. The adhesive layer is made of ultraviolet-curing silicone rubber, acrylic material, epoxy material, etc.

[0020] In addition, an annular frame 7 made of a metal material such as aluminum (Al) is attached to the outer peripheral region of the tape 5. A circular opening 7a having a diameter larger than that of the dressing board 3 is formed in this frame 7, and the frame 7 is attached to the tape 5 so that the center of the opening 7a coincides with the center of the dressing board 3.

[0021] Fig. 1 is a perspective view schematically showing an example of a cutting device. Note that the direction indicated by arrow X in Fig. 1 (X direction) is the forward direction, the direction indicated by arrow Y (Y direction) is the leftward direction, and the direction indicated by arrow Z (Z direction) is the upward direction.

[0022] 1 includes a base 4 that supports each component. A recess 4a extending along the X direction is formed on the top surface of the base 4. Inside the recess 4a, a flat table cover 6 and a bellows-like dustproof and drip-proof cover 8 that expands and contracts as the table cover 6 moves are provided.

[0023] A chuck table 10 is provided above the table cover 6. The chuck table 10 has a disk-shaped frame 10a made of ceramics or the like. The frame 10a has a disk-shaped bottom wall and cylindrical side walls extending from the outer periphery of the bottom wall. A disk-shaped porous plate 10b made of, for example, porous ceramics is fixed to a recess defined by the bottom wall and side walls of the frame 10a.

[0024] The porous plate 10b has a diameter approximately equal to the inner diameter of the side wall of the frame body 10a. Furthermore, the porous plate 10b communicates with a suction source (not shown), such as an ejector, provided inside the recess 4a via a through-hole or the like formed in the bottom wall of the frame body 10a. The upper surfaces of the side walls of the frame body 10a and the upper surface of the porous plate 10b are parallel to the X and Y directions, respectively, and function as the holding surface of the chuck table 10 when holding the dressing board 3 via the tape 5.

[0025] Specifically, when the frame unit 1 is loaded into the cutting device 2, the dressing board 3 is placed on the chuck table 10 via the tape 5. Then, when the suction source communicating with the porous plate 10b is operated in this state, a suction force acts on the dressing board 3 via the tape 5. As a result, the dressing board 3 is held on the holding surface of the chuck table 10.

[0026] Additionally, a plurality of clamps 12 are provided around the chuck table 10. The clamps 12 are provided at approximately equal angular intervals along the circumferential direction of the chuck table 10. When the frame unit 1 is carried into the cutting device 2, the clamps 12 grip the frame 7 at a position lower than the top surface of the chuck table 10.

[0027] The chuck table 10 and the multiple clamps 12 are connected to an X-direction movement mechanism (not shown) provided inside the recess 4a. This X-direction movement mechanism includes, for example, a ball screw and a motor for rotating the screw shaft of the ball screw. When this X-direction movement mechanism is operated, the chuck table 10 and the multiple clamps 12 move in the X direction or the opposite direction (front-to-back direction). Furthermore, in conjunction with this movement, the table cover 6 moves in the X direction or the opposite direction, and the dust-proof and drip-proof cover 8 expands and contracts.

[0028] The chuck table 10 and the clamps 12 are connected to a rotary drive source (not shown) provided inside the recess 4a. This rotary drive source includes, for example, a shaft, a pulley connected to the shaft, and a motor for rotating the pulley. When the rotary drive source is operated, the chuck table 10 and the clamps 12 rotate around a rotation axis that passes through the center of the holding surface of the chuck table 10 and is aligned in the Z direction.

[0029] A support structure 14 is provided in an area near the recess 4a on the upper surface of the base 4. This support structure 14 has an upright portion 14a that stands upright from the upper surface of the base 4, and an arm portion 14b that extends in the opposite direction to the Y direction (to the right) from an upper portion of the upright portion 14a so as to cross the recess 4a. A Y-direction movement mechanism 16 is provided on the front side of the arm portion 14b.

[0030] The Y-direction movement mechanism 16 is fixed to the front surface of the arm portion 14b and has a pair of guide rails 18 extending along the Y direction. A moving plate 20 is connected to the front surfaces of the pair of guide rails 18 in a manner that allows it to slide along the pair of guide rails 18.

[0031] A screw shaft 22 extending along the Y direction is disposed between the pair of guide rails 18. A motor (not shown) for rotating the screw shaft 22 is connected to one end of the screw shaft 22. A nut (not shown) that accommodates a large number of balls that roll on the surface of the rotating screw shaft 22 is provided on the surface of the screw shaft 22, on which a spiral groove is formed, thereby constituting a ball screw.

[0032] That is, when the screw shaft 22 rotates, a large number of balls circulate inside the nut, causing the nut to move in the Y direction or the opposite direction. The nut is fixed to the rear side of the moving plate 20. Therefore, when the screw shaft 22 is rotated by a motor connected to one end of the screw shaft 22, the moving plate 20 moves together with the nut in the Y direction or the opposite direction (left and right direction).

[0033] A Z-direction movement mechanism 24 is provided on the front side of the movable plate 20. This Z-direction movement mechanism 24 is fixed to the front side of the movable plate 20 and has a pair of guide rails 26 extending along the Z direction. A movable plate 28 is connected to the front sides of the pair of guide rails 26 in a manner that allows it to slide along the pair of guide rails 26.

[0034] A screw shaft 30 extending along the Z direction is disposed between the pair of guide rails 26. A motor 32 for rotating the screw shaft 30 is connected to one end (upper end) of the screw shaft 30. A nut (not shown) that accommodates a large number of balls that roll on the surface of the rotating screw shaft 30 is provided on the surface of the screw shaft 30 on which a spiral groove is formed, thereby forming a ball screw.

[0035] That is, when the screw shaft 30 rotates, a large number of balls circulate inside the nut, causing the nut to move in the Z direction or the opposite direction (up and down). The nut is fixed to the rear side of the moving plate 28. Therefore, when the screw shaft 30 is rotated by the motor 32, the moving plate 28 moves together with the nut in the Z direction or the opposite direction.

[0036] A cylindrical housing 34 is fixed to the lower part of the moving plate 28. A cutting unit 36 ​​is housed in the housing 34. However, some components of the cutting unit 36 ​​are exposed from the side surface of the housing 34 on the chuck table 10 side.

[0037] 3 is a plan view schematically showing the components of the cutting unit 36 ​​that are exposed and not housed in the housing 34. The components of the cutting unit 36 ​​shown in FIG. 3 are concentric structures centered on a line along the Y direction. Therefore, FIG. 3 can also be expressed as a front view schematically showing the components of the cutting unit 36 ​​that are exposed and not housed in the housing 34.

[0038] The cutting unit 36 ​​has a spindle 38 that extends along the Y direction and has a tip end that protrudes from the housing 34. The spindle 38 is supported by the housing 34 in a manner that allows it to rotate around a rotation axis that is a straight line parallel to the Y direction.

[0039] A cutting blade 40 is attached to the tip of the spindle 38. This cutting blade 40 has an annular cutting edge 40a that includes a binder made of metal, ceramic, resin, or the like, and abrasive grains made of diamonds or the like dispersed in this binder.

[0040] The base end of the spindle 38 is connected to a rotary drive source (not shown), such as a motor, housed in the housing 34. When this rotary drive source is operated, the cutting blade 40 rotates together with the spindle 38, with a straight line along the Y direction as the rotation axis.

[0041] 2, an imaging unit 42 capable of capturing an image of the holding surface side of the chuck table 10 is fixed to the lower part of the movable plate 28. The imaging unit 42 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.

[0042] Fig. 4 is a flow chart showing a schematic example of a dressing method for dressing the cutting edge 40a of the cutting blade 40. In this dressing method, first, the dressing board 3 is held on the holding surface of the chuck table 10 (holding step S1). Fig. 5 is a partially cross-sectional side view showing a schematic view of the holding step S1.

[0043] In the holding step S1, first, the frame unit 1 is placed on the holding surface of the chuck table 10 so that the center of the holding surface of the chuck table 10 and the center of the dressing board 3 overlap in the Z direction and the tape 5 is facing downward. Next, a suction source communicating with the porous plate 10b of the chuck table 10 is operated, and the frame 7 is gripped by the multiple clamps 12.

[0044] After the holding step S1, the relative positions of the chuck table 10 and the spindle 38 are adjusted so that the lower end (tip) of the cutting blade 40a is located between the front and back surfaces of the dressing board 3 (between one end and the other end in the Z direction) and directly behind the center of the dressing board 3 in a planar view (in the opposite direction of the X direction from the center of the dressing board 3 in a planar view), and is spaced apart from the dressing board 3 (positioning step S2). Figure 6(A) is a plan view schematically showing the positioning step S2, and Figure 6(B) is a partially cross-sectional side view schematically showing the positioning step S2.

[0045] In the positioning step S2, first, the position of the chuck table 10 in the X direction is adjusted so that the dressing board 3 is positioned forward of the cutting edge 40a of the cutting blade 40. Next, the position of the spindle 38 in the Y direction is adjusted so that the lower end of this cutting edge 40a is positioned directly behind the center C of the dressing board 3 in a plan view. Next, the position of the spindle 38 in the Z direction is adjusted so that the lower end of this cutting edge 40a is positioned slightly below the surface of the dressing board 3, for example, 1 μm to 5 μm below this surface.

[0046] After the positioning step S2, while both the chuck table 10 and the spindle 38 are rotated, the chuck table 10 is moved backward so that the lower end of the cutting blade 40a comes into contact with the dressing board 3 (dressing step S3). Fig. 7(A) is a plan view schematically showing the state of the dressing step S3, and Fig. 7(B) is a partially cross-sectional side view schematically showing the state of the dressing step S3.

[0047] In the dressing step S3, first, the chuck table 10 is rotated at, for example, 300 rpm to 500 rpm, and the spindle 38 is rotated at, for example, 20,000 rpm to 40,000 rpm. Next, while both the chuck table 10 and the spindle 38 are rotating, the chuck table 10 is moved backward at, for example, 10 mm / s to 30 mm / s so that the dressing board 3 comes into contact with the cutting edge 40a of the cutting blade 40.

[0048] When the dressing board 3 comes into contact with the cutting blade 40a, the portion of the dressing board 3 that has come into contact with the cutting blade 40a is removed, forming a small step 3a on its surface side, and the cutting blade 40a is dressed, flattening its outer peripheral surface. The chuck table 10 then continues to move rearward, for example, until the center C of the dressing board 3 reaches the lower end of the cutting blade 40a. In this case, the entire surface side of the dressing board 3 is removed. That is, in this case, no step 3a remains on the surface side of the dressing board 3 after the dressing step S3, and the surface becomes approximately flat.

[0049] After the center C of the dressing board 3 reaches the lower end of the cutting blade 40a, the chuck table 10 may be moved backward so that the dressing board 3 passes the lower end of the cutting blade 40a while both the chuck table 10 and the spindle 38 are still rotating, or the chuck table 10 may be moved forward so that it returns to its original position.

[0050] When the chuck table 10 is moved rearward so that the dressing board 3 passes over the lower end of the cutting blade 40a, the rotating dressing board 3 can be brought into contact with the lower end of the cutting blade 40a from the opposite direction. Therefore, from the viewpoint of making the outer peripheral surface of the cutting blade 40a flatter, it is preferable to move the chuck table 10 rearward so that the dressing board 3 passes over the lower end of the cutting blade 40a while both the chuck table 10 and the spindle 38 are rotating.

[0051] Furthermore, when the chuck table 10 is moved forward to return it to its original position, the direction in which the rotating cutting blade 40a cuts into the dressing board 3 changes, which may cause glazing on the outer circumferential surface of the cutting blade 40a. Therefore, from the perspective of suppressing glazing of the cutting blade 40a, it is preferable to move the chuck table 10 backward while keeping both the chuck table 10 and the spindle 38 rotating so that the dressing board 3 passes the lower end of the cutting blade 40a.

[0052] 4, the cutting edge 40a of the cutting blade 40 is dressed while rotating not only the spindle 38 to which the cutting blade 40 is attached at its tip, but also the chuck table 10 that holds the dressing board 3. Therefore, in this dressing method, the entire area of ​​the dressing board 3 can be dressed so that the thickness of the dressing board 3 is reduced approximately evenly.

[0053] 4 for each of the multiple dressings of the cutting blade 40a using the dressing board 3, it is possible to dress all of the parts of the dressing board 3 that can be used for dressing. In other words, in this case, it is possible to use the dressing board 3 efficiently.

[0054] Note that the above-described content is one aspect of the present invention, and the content of the present invention is not limited to the above-described content. For example, in the dressing method of the present invention, a standalone dressing board 3 may be used instead of a dressing board 3 integrated with a frame 7 via a tape 5. In other words, the dressing method of the present invention may be performed using a dressing board 3 that is held directly on the holding surface of the chuck table 10 without the tape 5.

[0055] Furthermore, the dressing board used in the dressing method of the present invention is not limited to the dressing board 3. Figures 8(A) and 8(B) are each a perspective view schematically showing an example of a frame unit including a dressing board different from the dressing board 3.

[0056] Specifically, the frame unit 9 shown in Figure 8(A) has a configuration similar to that of the frame unit 1, except that the dressing board 3 has been replaced with a circular plate-shaped dressing board 11. Also, the frame unit 13 shown in Figure 8(B) has a configuration similar to that of the frame unit 1, except that the dressing board 3 has been replaced with a rectangular plate-shaped dressing board 15.

[0057] Furthermore, the dressing method of the present invention is not limited to the dressing method shown in Fig. 4. For example, the dressing method of the present invention may differ from the dressing method shown in Fig. 4 in terms of the relative positions of the chuck table 10 and the spindle 38 before dressing the cutting blade 40a and / or the relative movement direction of the chuck table 10 and the spindle 38 when dressing the cutting blade 40a.

[0058] Fig. 9 is a flow chart that schematically shows an example of a dressing method that is different from the dressing method shown in Fig. 4. In this dressing method, first, the holding step S1 is carried out as described above.

[0059] After the holding step S1, the relative positions of the chuck table 10 and the spindle 38 are adjusted so that the lower end of the cutting blade 40a is positioned between the front and back surfaces of the dressing board 3 and between the left and right ends of the dressing board 3 in the Y direction, and is spaced apart from the dressing board 3 (positioning step S2'). Figure 10(A) is a plan view schematically showing the positioning step S2'.

[0060] In the positioning step S2', first, the position of the chuck table 10 in the X direction is adjusted so that the dressing board 3 is positioned forward of the cutting edge 40a of the cutting blade 40. Next, the position of the spindle 38 in the Y direction is adjusted so that the lower end of this cutting edge 40a is positioned between the left end L and the right end R of the dressing board 3 in the Y direction (between one end and the other end in the Y direction) (excluding directly behind the center C of the dressing board 3 in a plan view). Next, the position of the spindle 38 in the Z direction is adjusted so that the lower end of this cutting edge 40a is positioned slightly below the surface of the dressing board 3.

[0061] After the positioning step S2', the dressing step S3 is performed as described above. Figure 10(B) is a plan view schematically showing the dressing board 3 after the dressing step S3. In the dressing step S3 shown in Figure 9, the central region on the surface side of the dressing board 3 is not removed. Therefore, the surface of the dressing board 3 after this dressing step S3 is not flat, and a step 3b remains on the surface side.

[0062] After the cutting edge 40a of the cutting blade 40 has been dressed by carrying out the dressing method shown in Fig. 9, if it becomes necessary to dress the cutting edge 40a again, the dressing method shown in Fig. 4 can be carried out. In this case, the cutting edge 40a can be dressed again by utilizing the central region on the front surface side of the dressing board 3 that remained undressed during the previous dressing.

[0063] Fig. 11 is a flowchart schematically showing an example of a dressing method in which the relative movement direction between the chuck table 10 and the spindle 38 when dressing the cutting blade 40a is different from the dressing method shown in Fig. 4. In this dressing method, first, the holding step S1 is performed as described above.

[0064] After the holding step S1, the relative positions of the chuck table 10 and the spindle 38 are adjusted so that the lower end of the cutting blade 40a is located between the front and back surfaces of the dressing board 3, directly to the left of the center C of the dressing board 3 in a planar view (in the Y direction as viewed from the center C of the dressing board 3 in a planar view), and is spaced apart from the dressing board 3 (positioning step S2''). Figure 12(A) is a plan view schematically showing the positioning step S2''.

[0065] In this positioning step S2'', first, the position of the spindle 38 in the Y direction is adjusted so that the cutting edge 40a of the cutting blade 40 is positioned to the left of the dressing board 3. Next, the position of the chuck table 10 in the X direction is adjusted so that the lower end of this cutting edge 40a is positioned directly to the left of the center C of the dressing board 3 in a planar view. Next, the position of the spindle 38 in the Z direction is adjusted so that the lower end of this cutting edge 40a is positioned slightly below the surface of the dressing board 3.

[0066] After the positioning step S2'', while both the chuck table 10 and the spindle 38 are rotated, the spindle 38 is moved to the right so that the lower end of the cutting blade 40a comes into contact with the dressing board 3 (dressing step S3'). Figure 12(B) is a plan view schematically showing the state of the dressing step S3'.

[0067] In this dressing step S3', first, the chuck table 10 is rotated at, for example, 300 rpm to 500 rpm, and the spindle 38 is rotated at, for example, 20,000 rpm to 40,000 rpm. Next, while both the chuck table 10 and the spindle 38 are rotating, the spindle 38 is moved rightward at, for example, 1 mm / s to 10 mm / s so that the cutting edge 40a of the cutting blade 40 contacts the dressing board 3.

[0068] When the dressing board 3 comes into contact with the cutting blade 40a, the portion of the dressing board 3 that has come into contact with the cutting blade 40a is removed, forming a small step 3c on its surface side, and the cutting blade 40a is dressed, flattening its outer peripheral surface. The spindle 38 then continues to move to the right, for example, until the lower end of the cutting blade 40a reaches at least the center C of the dressing board 3. In this case, the entire surface side of the dressing board 3 is removed. That is, in this case, no step 3c remains on the surface side of the dressing board 3 after the dressing step S3', and the surface becomes approximately flat.

[0069] After the lower end of the cutting blade 40a reaches the center C of the dressing board 3, the spindle 38 may be moved to the right so that the lower end of the cutting blade 40a passes the dressing board 3 while both the chuck table 10 and the spindle 38 are still rotating, or the spindle 38 may be moved to the left so that it returns to its original position.

[0070] 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]

[0071] 1: Frame unit 2:Cutting device 3: Dressing board (3a, 3b, 3c: steps) 4: Base (4a: recess) 5: Tape 6: Table cover 7: Frame (7a: Opening) 8: Dustproof and water-resistant cover 9: Frame unit 10: chuck table (10a: frame, 10b: porous plate) 11: Dressing board 12: Clamp 13: Frame unit 14: Support structure (14a: standing part, 14b: arm part) 15: Dressing board 16:Y direction movement mechanism 18: Guide rail 20: Moving plate 22: Screw shaft 24:Z direction movement mechanism 26: Guide rail 28: Moving plate 30:Screw shaft 32: Motor 34: Housing 36: Cutting unit 38: Spindle 40: Cutting blade (40a: cutting blade) 42: Imaging unit

Claims

1. A cutting device including a chuck table rotatable about a rotation axis that is a straight line that passes through the center of a holding surface and that is aligned along a first direction perpendicular to the holding surface, and a spindle having a cutting blade with an annular cutting edge attached to a tip end thereof and extending along a second direction perpendicular to the first direction, comprising: a holding step of holding a dressing board on the holding surface of the chuck table; a positioning step of adjusting the relative position of the chuck table and the spindle so that the tip of the cutting blade is located between one end and the other end of the dressing board in the first direction, and between one end and the other end of the dressing board in a third direction perpendicular to the first direction, and is spaced apart from the dressing board in a fourth direction perpendicular to both the first direction and the third direction; A dressing method comprising: a dressing step of rotating both the chuck table and the spindle while moving the chuck table and the spindle relatively along the fourth direction so as to bring the tip of the cutting blade into contact with the dressing board.

2. 2. The dressing method according to claim 1, wherein the third direction is the same as the second direction.

3. 3. The dressing method according to claim 1, wherein in the positioning step, the tip of the cutting blade is positioned at the same position as the center of the holding surface of the chuck table in the third direction.

Images