How to dress cutting blades

Abstract

To remove undulation from a cutting blade by dressing the cutting blade.SOLUTION: A dressing method for a cutting blade, for dressing the cutting blade by means of a cutting device including a holding mechanism, a cutting unit with a rotatably provided cutting blade, a cutting water supply unit for supplying cutting water to a cutting area, and a processing feed unit for processing and feeding the holding mechanism, includes: a holding step of holding a dressing board containing abrasive grains, by means of the holding mechanism; and a dressing step of cutting the dressing board by means of the cutting blade; wherein, in the dressing step, a rotational speed of the cutting blade is set at 1000 rpm or more and 3000 rpm or less; a flow rate of cutting water supplied from the cutting water supply unit is set at 10 mL / min or more and 50 mL / min or less; and a processing feed speed of the cutting unit and the holding mechanism is set at 100 mm / min or more and 500 mm / min or less.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a method for dressing a cutting blade that is carried out when improving the cutting ability of an annular cutting blade that cuts a workpiece such as a semiconductor wafer. [Background technology]

[0002] Device chips used in electronic devices such as mobile phones and computers are formed by dividing a semiconductor wafer, on which multiple devices are arranged in a row on its surface, into individual devices. When dividing a semiconductor wafer, for example, a cutting device equipped with a cutting blade having an annular cutting edge on its outer periphery is used (see Patent Document 1). By moving the cutting blade and the workpiece relative to each other while cutting into the workpiece with the cutting blade rotating at high speed, the workpiece can be cut along the path of this movement.

[0003] The cutting edge of the cutting blade has abrasive grains such as diamond and a bond (binding material) that disperses and fixes the abrasive grains. The surface of the cutting edge is composed of the bond and the abrasive grains protruding from the bond. When the rotating cutting blade is cut into the workpiece while supplying cutting water such as pure water to the workpiece, the abrasive grains exposed from the bond come into contact with the workpiece and cut it.

[0004] As the workpiece is cut, the abrasive grains wear down, but the bond also wears away, gradually exposing unused abrasive grains that had been buried. This maintains the cutting blade's cutting ability. Furthermore, when the bond has not worn down sufficiently or when the cutting blade is first used, and the abrasive grains are not fully exposed, a dressing board, which actively wears the cutting edge as it is cut, is used with the cutting blade under the same conditions as the workpiece. This process is called dressing (see Patent Documents 2 and 3). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-258235 [Patent Document 2] JP 2013-129052 A [Patent Document 3] JP 2018-94637 A Summary of the Invention [Problem to be solved by the invention]

[0006] Cutting blades attached to cutting equipment can develop a morphological abnormality called waviness. Waviness refers to a condition in which a part of the cutting edge is slightly warped from a plane perpendicular to the blade's rotation axis. When a workpiece is cut with a waviness-caused cutting blade, the edges of the cutting groove formed in the workpiece become rough, causing frequent chipping, which leads to a decrease in processing quality.

[0007] In order to remove the waviness from a cutting blade that has developed, it is conceivable to wear down the slightly raised and depressed portions of the cutting edge, but it is difficult to sufficiently remove these raised portions with normal cutting blade dressing.

[0008] The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for dressing a cutting blade that can remove undulations from a cutting blade that has undulations. [Means for solving the problem]

[0009] According to one aspect of the present invention, there is provided a method for dressing a cutting blade in a cutting device including a holding mechanism, a cutting unit having a rotatable cutting blade, a cutting water supply unit for supplying cutting water to a cutting area where cutting is performed by the cutting blade, and a processing feed unit for relatively processing-feeding the holding mechanism and the cutting unit, the method including: a holding step for holding a dressing board containing abrasive grains with the holding mechanism; and a dressing step for rotating the cutting blade, relatively processing-feeding the cutting unit and the holding mechanism with the processing feed unit, and cutting the dressing board held by the holding mechanism with the cutting blade while supplying cutting water from the cutting water supply unit to the cutting area; L / min or less, and the processing feed rate of the cutting unit and the holding mechanism is set to 100 mm / min or more and 500 mm / min or less.

[0010] Preferably, in the dressing process, the dressing board is cut with the cutting blade to disperse the abrasive grains contained in the dressing board into the cutting water that accumulates on the dressing board, and the cutting blade is brought into contact with the abrasive grains contained in the cutting water.

[0011] According to another aspect of the present invention, there is provided a dressing method for dressing a cutting blade in a cutting device comprising a holding mechanism, a cutting unit having a rotatable cutting blade, a cutting water supply unit for supplying cutting water to a cutting area where cutting is performed by the cutting blade, and a processing feed unit for relatively processing-feeding the holding mechanism and the cutting unit, the method comprising: a holding step for holding a dressing board containing abrasive grains with the holding mechanism; and a dressing step for rotating the cutting blade, relatively processing-feeding the cutting unit and the holding mechanism with the processing feed unit, and cutting the dressing board held by the holding mechanism with the cutting blade while supplying cutting water from the cutting water supply unit to the cutting area, wherein in the dressing step: The flow rate of the cutting water supplied from the cutting water supply unit is set to 10 mL / min or more and 50 mL / min or less, A method for dressing a cutting blade is provided, which comprises cutting the dressing board with the cutting blade to disperse the abrasive grains contained in the dressing board into the cutting water that accumulates on the dressing board, and bringing the cutting blade into contact with the abrasive grains contained in the cutting water.

[0012] Preferably, the holding mechanism is a chuck table capable of holding a workpiece or a sub-chuck table not capable of holding a workpiece. [Effects of the Invention]

[0013] In a method for dressing a cutting blade according to one aspect of the present invention, a dressing board containing abrasive grains is cut by the cutting blade. At this time, the abrasive grains contained in the dressing board are dispersed in a cutting fluid. Generally, when cutting a workpiece with a cutting blade, cutting fluid is supplied at a sufficient flow rate to actively remove cutting debris generated from the cut workpiece so that the cutting debris does not remain on the workpiece.

[0014] In contrast, in a cutting blade dressing method according to one aspect of the present invention, the rotation speed of the cutting blade is set to a relatively low speed, the flow rate of the cutting fluid supplied from the cutting fluid supply unit is set to a relatively low speed, and the processing feed rate is set to a relatively low speed, thereby intentionally leaving the abrasive grains contained in the dressing board in the cutting fluid.

[0015] This allows the abrasive grains contained in the cutting water that accumulates on the dressing board to hit the rotating cutting blade, machining the cutting blade with high precision. As a result, the raised part of the wavy cutting blade is removed, eliminating the wavy cutting blade.

[0016] Therefore, according to one aspect of the present invention, there is provided a method for dressing a cutting blade that can remove waviness from a cutting blade that has developed waviness. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a perspective view schematically showing a cutting device, a workpiece, and a dressing board. [Figure 2] Figure 2(A) is a cross-sectional view schematically showing how a cutting blade is dressed with a dressing board held on a chuck table, and Figure 2(B) is a cross-sectional view schematically showing how a cutting blade is dressed with a dressing board held on a sub-chuck table. [Figure 3] FIG. 10 is a perspective view schematically showing the process of dressing a cutting blade with a dressing board. DETAILED DESCRIPTION OF THE INVENTION

[0018] An embodiment of the present invention will be described with reference to the accompanying drawings. In the cutting blade dressing method according to this embodiment, a cutting blade attached to a cutting device is dressed. First, the cutting blade to be dressed, the cutting device to which the cutting blade is attached and used, and the workpiece to be cut by the cutting blade will be described. Fig. 1 is a perspective view schematically showing a cutting device 2 and a workpiece 1.

[0019] The workpiece 1 is, for example, a wafer made of a material such as Si (silicon), SiC (silicon carbide), GaN (gallium nitride), GaAs (gallium arsenide), or other semiconductor. Alternatively, the workpiece 1 is a substantially disk-shaped substrate made of a material such as sapphire, glass, or quartz. The glass may be, for example, alkali glass, non-alkali glass, soda-lime glass, lead glass, borosilicate glass, or quartz glass.

[0020] 1 is a schematic perspective view of a workpiece 1. A plurality of devices 3, such as ICs (Integrated Circuits) and LSIs (Large Scale Integration), are formed on a surface 1a of the workpiece 1. By dividing the workpiece 1 into individual devices 3, individual device chips can be formed.

[0021] A cutting device 2 is used to divide the workpiece 1. When the workpiece 1 is carried into the cutting device 2, an adhesive tape 5 is attached in advance to the back side of the workpiece 1 so as to cover the opening of an annular frame 7 made of metal or the like. Then, the workpiece 1 is carried into the cutting device 2 as a frame unit 9 in which the workpiece 1, adhesive tape 5, and annular frame 7 are integrated, and the workpiece 1 is cut. Then, the individual device chips formed by dividing the workpiece 1 are supported by the adhesive tape 5 and then picked up from the adhesive tape 5.

[0022] The cutting device 2 includes a base 4 that supports each of the components. An opening 4a is formed in the front corner of the base 4, and a cassette support table 8 that is raised and lowered by a lifting mechanism (not shown) is provided within this opening 4a. A cassette 10 that stores a plurality of workpieces 1 is mounted on the upper surface of the cassette support table 8. For ease of explanation, only the outline of the cassette 10 is shown in FIG. 1.

[0023] A rectangular opening 4b is formed on the side of the cassette support base 8 so that its longitudinal direction is along the X-axis direction (front-rear direction, processing feed direction). Inside the opening 4b, there are arranged a ball screw type X-axis movement mechanism (processing feed unit) 14, a table cover 14a that covers the top of the X-axis movement mechanism 14, and a dustproof and drip-proof cover 16. The X-axis movement mechanism 14 has an X-axis movement table (not shown) covered by the table cover 14a, and moves this X-axis movement table in the X-axis direction.

[0024] A chuck table (holding mechanism) 18 that holds the workpiece 1 by suction is provided on the upper surface of the X-axis moving table so as to be exposed from the table cover 14a. This chuck table 18 is connected to a rotary drive source (not shown) such as a motor, and rotates around a rotation axis that is roughly parallel to the Z-axis direction (vertical direction). In addition, the chuck table (holding mechanism) 18 moves in the X-axis direction together with the X-axis moving table and table cover 14a by the X-axis moving mechanism 14.

[0025] The X-axis movement mechanism (processing feed unit) 14 may move cutting units 24a and 24b (described later) along the X-axis direction (processing feed direction) instead of the chuck table (holding mechanism) 18. The X-axis movement mechanism (processing feed unit) 14 performs processing feed between the chuck table (holding mechanism) 18 and the cutting units 24a and 24b relative to each other.

[0026] The upper surface of the chuck table 18 is a holding surface 18a that suction-holds the workpiece 1. The holding surface 18a is formed generally parallel to the X-axis direction and the Y-axis direction, and is connected to a suction source (not shown) such as an ejector via a suction path (not shown) or the like provided inside the chuck table 18. Four clamps 18b are provided around the periphery of the chuck table 18 to fix the annular frame 7 that supports the workpiece 1 from all four sides.

[0027] In addition, a transport unit (not shown) that transports the workpiece 1 to the chuck table 18 and the like is disposed in an area adjacent to the opening 4b. A temporary placement mechanism for temporarily placing the workpiece 1 is provided in a position close to the side of the cassette support table 8. The temporary placement mechanism includes, for example, a pair of guide rails 12 that move toward and away from each other while maintaining a state parallel to the Y-axis direction (indexing feed direction). The pair of guide rails 12 sandwich the workpiece 1 pulled out of the cassette 10 by the transport unit in the X-axis direction and align it to a predetermined position.

[0028] The workpiece 1 aligned to a predetermined position is lifted up by the transport unit and transported to the chuck table 18. At this time, the pair of guide rails 12 are separated from each other, and the workpiece 1 is passed between the pair of guide rails 12.

[0029] A first cutting unit 24a and a second cutting unit 24b that use annular cutting blades to cut the workpiece 1 are provided above the chuck table 18. A gate-shaped support structure 20 for supporting the first cutting unit 24a and the second cutting unit 24b is disposed on the upper surface of the base 4 so as to straddle the opening 4b.

[0030] A first moving unit 22a that moves the first cutting unit 24a in the Y-axis direction and the Z-axis direction, and a second moving unit 22b that moves the second cutting unit 24b in the Y-axis direction and the Z-axis direction are provided on the upper front surface of the support structure 20.

[0031] The first moving unit 22a includes a Y-axis moving plate 28a, and the second moving unit 22b includes a Y-axis moving plate 28b. The Y-axis moving plate 28a and the Y-axis moving plate 28b are slidably mounted on a pair of Y-axis guide rails 26 that are arranged along the Y-axis direction on the front surface of the support structure 20.

[0032] A nut portion (not shown) is provided on the back surface (rear surface) of Y-axis moving plate 28a, and a Y-axis ball screw 30a that is generally parallel to Y-axis guide rail 26 is screwed into this nut portion. In addition, a nut portion (not shown) is provided on the back surface (rear surface) of Y-axis moving plate 28b, and a Y-axis ball screw 30b that is generally parallel to Y-axis guide rail 26 is screwed into this nut portion.

[0033] A Y-axis pulse motor 32a is coupled to one end of the Y-axis ball screw 30a. When the Y-axis pulse motor 32a rotates the Y-axis ball screw 30a, the Y-axis moving plate 28a moves in the Y-axis direction along the Y-axis guide rail 26. Furthermore, a Y-axis pulse motor (not shown) is coupled to one end of the Y-axis ball screw 30b. When the Y-axis pulse motor rotates the Y-axis ball screw 30b, the Y-axis moving plate 28b moves in the Y-axis direction along the Y-axis guide rail 26.

[0034] A pair of Z-axis guide rails 34a are provided along the Z-axis direction on the surface (front surface) side of Y-axis moving plate 28a, and a pair of Z-axis guide rails 34b are provided along the Z-axis direction on the surface (front surface) side of Y-axis moving plate 28b. Furthermore, a Z-axis moving plate 36a is slidably attached to the pair of Z-axis guide rails 34a, and a Z-axis moving plate 36b is slidably attached to the pair of Z-axis guide rails 34b.

[0035] A nut (not shown) is provided on the back side (rear side) of Z-axis moving plate 36a, and Z-axis ball screw 38a, which is provided in a direction generally parallel to Z-axis guide rail 34a, is threadedly engaged with this nut. Z-axis pulse motor 40a is connected to one end of Z-axis ball screw 38a, and by rotating Z-axis ball screw 38a with Z-axis pulse motor 40a, Z-axis moving plate 36a moves in the Z-axis direction along Z-axis guide rail 34a.

[0036] A nut (not shown) is provided on the back side (rear side) of Z-axis moving plate 36b, and Z-axis ball screw 38b, which is provided in a direction generally parallel to Z-axis guide rail 34b, is threadedly engaged with this nut. Z-axis pulse motor 40b is connected to one end of Z-axis ball screw 38b, and by rotating Z-axis ball screw 38b with Z-axis pulse motor 40b, Z-axis moving plate 36b moves in the Z-axis direction along Z-axis guide rail 34b.

[0037] A first cutting unit 24a is provided below the Z-axis moving plate 36a. A camera unit 46a is provided adjacent to the first cutting unit 24a to capture an image of the workpiece 1 held by suction on the chuck table 18 and identify the processing location. A second cutting unit 24b is provided below the Z-axis moving plate 36b. A camera unit 46b is provided adjacent to the second cutting unit 24b to capture an image of the workpiece 1 held by suction on the chuck table 18.

[0038] The first moving unit 22a controls the positions of the first cutting unit 24a and camera unit 46a in the Y-axis and Z-axis directions, and the second moving unit 22b controls the positions of the second cutting unit 24b and camera unit 46b in the Y-axis and Z-axis directions. That is, the positions of the first cutting unit 24a and the second cutting unit 24b are controlled independently of each other.

[0039] An opening 4c is formed at a position opposite to the opening 4b from the opening 4a. A cleaning unit 48 for cleaning the workpiece 1 is disposed in the opening 4c, and the workpiece 1 that has been subjected to a predetermined processing on the chuck table 18 is cleaned by the cleaning unit 48.

[0040] 2(A) and 2(B), the first cutting unit 24a includes a spindle 42a whose axis is generally parallel to the holding surface 18a of the chuck table 18, and a cutting blade 44a attached to the tip of the spindle 42a. The second cutting unit 24b includes a spindle 42b whose axis is generally parallel to the holding surface 18a of the chuck table 18, and a cutting blade 44b attached to the tip of the spindle 42b.

[0041] 3 is a perspective view showing the cutting units 24a and 24b. Each cutting unit 24a and 24b further includes a blade cover 54 that covers the outer periphery of the cutting blade 44a and 44b, and a housing 56 that houses a rotation drive source connected to the base end of the spindle 42a and 42b.

[0042] A pair of cutting water supply units (cutting water supply nozzles) 58 extending along both side surfaces of the cutting blades 44a, 44b are attached to the blade cover 54. The cutting water supply unit 58 is provided with a plurality of nozzles (not shown) facing the cutting blades 44a, 44b.

[0043] When the workpiece 1 is cut, cutting water 60 such as pure water is supplied to the cutting area where cutting is being performed. That is, the cutting water 60 is supplied to the workpiece 1 and the cutting blades 44a, 44b from the cutting water supply unit 58. Cutting chips and processing heat generated from the workpiece 1 and the cutting blades 44a, 44b when the workpiece 1 is cut are taken in by the cutting water 60 and removed.

[0044] The cutting blades 44a and 44b have a cutting edge (grindstone portion) on the periphery, in which abrasive grains made of diamond or the like are dispersed and fixed with a bond made of resin or a metal such as nickel. The grindstone is formed, for example, on the outer periphery of an annular base made of metal. Cutting blades with this annular base are called hub type. Also, the cutting blades 44a and 44b do not necessarily have an annular base. Cutting blades without this annular base are called washer type.

[0045] There are multiple types of cutting blades 44a, 44b. For example, there are multiple types that differ in the shape, size, and amount of abrasive grains contained in the cutting edge (grindstone portion), and there are also multiple types that differ in bond material, blade thickness, diameter, etc. When cutting the workpiece 1, the type of cutting blade 44a, 44b appropriate for the cutting process is selected based on the material, size, and shape of the workpiece 1 and the cutting process content, and is attached to the tip of the spindle 42a, 42b.

[0046] Abrasive grains are exposed from the bond on the surface of the cutting blade. When the cutting blades 44a, 44b are rotated and cut into the workpiece 1 held by the chuck table 18 while cutting water 60 is supplied to the workpiece 1 and the cutting blades 44a, 44b from the cutting water supply nozzle, the abrasive grains come into contact with the workpiece 1 and cut it.

[0047] As the workpiece 1 is cut, the abrasive grains wear down, but the bond also wears away, and unused abrasive grains that were buried beneath the surface are gradually exposed. This maintains the cutting ability of the cutting blades 44a, 44b. Furthermore, when the bond has not worn down sufficiently or when the cutting blades 44a, 44b are first used, and the abrasive grains are not fully exposed, a dressing board, which actively wears the cutting edge as it is cut, is used by the cutting blades 44a, 44b to cut the workpiece 1 under the same conditions. This process is called dressing.

[0048] As shown in Fig. 1, the cutting device 2 is provided with rectangular sub-chuck tables (holding mechanisms) 50a, 50b capable of holding the dressing board 13, positioned adjacent to the chuck table 18. Side views of the sub-chuck tables 50a, 50b are shown in Fig. 2(A) and Fig. 2(B). The upper surfaces of the sub-chuck tables 50a, 50b form holding surfaces 52a, 52b, and the interiors of the sub-chuck tables 50a, 50b are provided with suction paths, one end of which communicates with the holding surfaces 52a, 52b, and a suction source connected to the other end of the suction path.

[0049] The dressing board 13 includes, for example, a bond and abrasive grains dispersed and fixed in the bond. When the dressing board 13 is placed on the sub-chuck tables 50a, 50b and the suction source is activated, the dressing board 13 is held by the sub-chuck tables 50a, 50b. When the cutting blades 44a, 44b are caused to cut the dressing board 13, the cutting blades 44a, 44b can be dressed.

[0050] The dressing board 13 may be held on the chuck table 18 instead of the sub-chuck tables 50a, 50b. In this case, for example, a frame unit is formed in which a dressing board is incorporated instead of the workpiece 1. Figure 3 includes a perspective view schematically showing a frame unit 9a in which a dressing board 13a is incorporated. That is, an adhesive tape 5a attached so as to cover the opening of the annular frame 7a is adhered to the back side of the dressing board 13a.

[0051] When dressing the cutting blades 44a, 44b, the dressing boards 13, 13a are cut by the cutting blades 44a, 44b under the same conditions as when cutting the workpiece 1. That is, the cutting blades 44a, 44b are rotated at the same rotational speed as when cutting the workpiece 1, and the holding mechanisms (chuck table 18, sub-chuck tables 50a, 50b) are processed and fed at the same processing feed speed. Then, cutting water is supplied to the workpiece 1, etc. from the cutting water supply unit 58 at the same supply amount as when cutting the workpiece 1.

[0052] The cutting blades 44a, 44b attached to the cutting device 2 may develop a morphological abnormality called waviness. Waviness refers to a state in which a part of the cutting edge of the cutting blade 44a, 44b is warped slightly from a plane perpendicular to the rotation axis of the cutting blade 44a, 44b. When the workpiece 1 is cut with the cutting blades 44a, 44b with waviness, the edges of the cutting groove formed in the workpiece 1 become rough, causing a lot of chipping, which leads to a decrease in processing quality.

[0053] One way to remove the waviness from the cutting blades 44a, 44b is to wear down the slightly uneven portions of the cutting edges. However, it is difficult to sufficiently remove these portions by normal dressing of the cutting blades 44a, 44b. While it is possible to remove the cutting blades 44a, 44b from the cutting device 2 and repair them, replacing the cutting blades 44a, 44b takes time and effort, which reduces the efficiency of the cutting device 2 in processing the workpiece 1.

[0054] Therefore, in the cutting blade dressing method according to this embodiment, dressing is performed to remove the waviness without removing the cutting blades 44a, 44b from the cutting device 2. The cutting blade dressing method according to this embodiment will be described below.

[0055] In the cutting blade dressing method according to this embodiment, first, a holding step is carried out in which the dressing boards 13, 13a containing abrasive grains are held by a holding mechanism (chuck table 18, sub-chuck tables 50a, 50b). Below, an example will be described in which the cutting blades 44a, 44b are dressed by the dressing board 13a held by the chuck table 18, but the holding mechanism is not limited to the chuck table 18.

[0056] First, a frame unit 9a including a dressing board 13a is formed, and the frame unit 9a is placed on the holding surface 18a of the chuck table 18. Then, the annular frame 7 is gripped by the clamp 18b, and the dressing board 13a is suction-held by the chuck table 18 via the adhesive tape 5. Figure 2(A) schematically shows the dressing board 13a suction-held on the chuck table 18.

[0057] After the holding step, the dressing step is carried out. Fig. 2(A) is a cross-sectional view showing the dressing step, and Fig. 3 is a perspective view showing the dressing step. In the dressing step, the spindles 42a, 42b are rotated to rotate the cutting blades 44a, 44b, and the cutting units 24a, 24b and the chuck table (holding mechanism) 18 are fed for processing by the X-axis moving mechanism (processing feed unit) 14.

[0058] Then, while cutting water 60 is supplied from a cutting water supply unit (cutting water supply nozzle) 58 to the cutting area, the dressing board 13a held by the chuck table (holding mechanism) 18 is cut by the cutting blades 44a and 44b.

[0059] Here, in the cutting blade dressing method according to this embodiment, the dressing board 13a is cut by the cutting blades 44a, 44b under cutting conditions different from those used when cutting the workpiece 1. Details of the cutting conditions will be described later, but in short, these cutting conditions are relatively weaker than the cutting conditions normally set when cutting the workpiece 1.

[0060] For example, the rotation speed of the cutting blades 44a, 44b is slower than when cutting the workpiece 1, the flow rate of cutting water supplied from the cutting water supply unit 58 is reduced, and the processing feed speed of the cutting units 24a, 24b and the chuck table (holding mechanism) 18 is slowed. As a result, in the dressing process, the cutting water 60 supplied to the dressing board 13a is prevented from being blown away and is allowed to remain on the dressing board 13a as shown in Figure 3.

[0061] When the dressing board 13a is cut with the cutting blades 44a, 44b while cutting water 60 is accumulating on the dressing board 13a, the abrasive grains contained in the dressing board 13a remain dispersed in the cutting water 60 that accumulates on the dressing board 13a. In this case, the abrasive grains contained in the cutting water 60 come into contact with the cutting blades 44a, 44b.

[0062] As a result, the cutting blades 44a, 44b are not only dressed by the dressing board 13a but also cut by the abrasive grains contained in the cutting water 60, so that the cutting blades 44a, 44b are machined with high precision. As a result, the undulations of the cutting blades 44a, 44b that have occurred are eliminated.

[0063] The cutting conditions of the dressing board 13a in the dressing step will be described in detail, in comparison with the normal cutting conditions when cutting the workpiece 1. When cutting the workpiece 1, for example, the rotation speed of the cutting blades 44a, 44b is set to 6000 rpm or more and 40000 rpm or less. In contrast, in the dressing step of the cutting blade dressing method according to this embodiment, the rotation speed of the cutting blades 44a, 44b is set to 1000 rpm or more and 3000 rpm or less.

[0064] Similarly, when cutting the workpiece 1, the flow rate of the cutting water 60 supplied from the cutting water supply unit 58 is set to, for example, 1 L / min or more and 3 L / min or less. In contrast, in the dressing step of the cutting blade dressing method according to this embodiment, the flow rate of the cutting water 60 supplied from the cutting water supply unit 58 is set to 10 mL / min or more and 50 mL / min or less.

[0065] Furthermore, when cutting the workpiece 1, for example, the processing feed rate of the cutting units 24a, 24b and the chuck table (holding mechanism) 18 is set to 5 mm / min or more and 12,000 mm / min or less. In contrast, in the dressing step of the cutting blade dressing method according to this embodiment, the processing feed rate of the cutting units 24a, 24b and the chuck table (holding mechanism) 18 is set to 100 mm / min or more and 500 mm / min or less.

[0066] However, the cutting conditions for the dressing board 13a in the dressing process are not limited to these. Depending on the model of the cutting device 2, the rotation speed of the cutting blades 44a, 44b may not be set between 1000 rpm and 3000 rpm, and the minimum settable rotation speed may exceed 3000 rpm. In this case, it is recommended to rotate the cutting blades 44a, 44b at the minimum rotation speed that can be set by the cutting device 2. Similarly, the supply rate of cutting water 60 may exceed 50 mL / min.

[0067] Furthermore, the processing feed speed of the cutting units 24a, 24b and the chuck table (holding mechanism) 18 may be determined by back-calculating from the required time set for the dressing process. For example, if the rotation speed of the cutting blades 44a, 44b in the dressing process is set to one-tenth of the rotation speed when cutting the workpiece 1, the processing feed speed of the chuck table (holding mechanism) 18 should also be set to about one-tenth. As a result, the amount of dressing board 13a consumed in the dressing process is also reduced.

[0068] When the cutting blades 44a, 44b dressed by the cutting blade dressing method according to this embodiment were observed, it was confirmed that the waviness had been removed and the side surfaces had been smoothed and cleaned. Furthermore, when the workpiece 1 was machined with the cutting blades 44a, 44b dressed by the cutting blade dressing method according to this embodiment, it was confirmed that the amount and size of chipping around the cutting grooves formed in the workpiece 1 was reduced.

[0069] As described above, when the cutting blades 44a, 44b are dressed using the cutting blade dressing method according to this embodiment, waviness can be removed from the cutting blades 44a, 44b. In this case, there is no need to remove the cutting blades 44a, 44b from the cutting device 2, and the dressing boards that have been used conventionally can be used as is. In addition, there is no need to modify the cutting device 2 to perform special functions. Therefore, the cutting blades 44a, 44b can be dressed with high quality and high efficiency.

[0070] The present invention is not limited to the above embodiment and can be implemented with various modifications. For example, in the above embodiment, a frame unit 9a including a dressing board 13a is held by suction on a chuck table 18, and the dressing board 13a held on the chuck table 18 is cut by cutting blades 44a and 44b. However, one aspect of the present invention is not limited to this.

[0071] That is, in the holding step, the dressing board 13 containing abrasive grains may be held by the sub-chuck tables 50a, 50b. Then, in the dressing step, the dressing board 13 held by the sub-chuck tables 50a, 50b may be cut by the cutting blades 44a, 44b. That is, in the cutting blade dressing method according to one embodiment of the present invention, the holding mechanism is the chuck table 18 that can hold the workpiece 1 or the sub-chuck tables 50a, 50b that cannot hold the workpiece 1.

[0072] 2(B) includes a cross-sectional view that schematically shows the workpiece 1 held by the chuck table 18 and the dressing board 13 held by the sub-chuck tables 50a, 50b. For example, if waviness occurs in the cutting blades 44a, 44b and the quality of the cutting blades 44a, 44b no longer meets an acceptable level while cutting the workpiece 1, the cutting of the workpiece 1 may be interrupted and the cutting blades 44a, 44b may be dressed.

[0073] Even in this case, the cutting blades 44a, 44b are caused to cut the dressing board 13 under the above-mentioned cutting conditions. In other words, by cutting the dressing board 13 with the cutting blades 44a, 44b, the abrasive grains contained in the dressing board 13 are dispersed into the cutting water 60 that accumulates above the dressing board 13. Then, dressing is performed by causing the cutting blades 44a, 44b to cut with the abrasive grains contained in the cutting water 60. Thereafter, cutting of the workpiece 1 held by the chuck table 18 may be resumed.

[0074] In addition, the structures, methods, etc. according to the above-described embodiments and modifications can be modified as appropriate without departing from the scope of the present invention. [Explanation of symbols]

[0075] 1 Workpiece 1a surface 3 Devices 5,5a adhesive tape 7,7a Annular frame 9,9a Frame unit 13,13a Dressing board 2 Cutting equipment 4 Foundation 4a,4b,4c opening 8 Cassette support stand 10 cassettes 12 Guide rail 14 X-axis movement mechanism 14a Table cover 16 Dustproof and water-resistant cover 18 Chuck table 18a Holding surface 18b clamp 20 Support structure 22a, 22b Mobile unit 24a, 24b Cutting unit 26 Y-axis guide rail 28a, 28b Y-axis moving plate 30a, 30b Y-axis ball screw 32a Y-axis pulse motor 34a, 34b Z-axis guide rail 36a, 36b Z-axis moving plate 38a, 38b Z-axis ball screw 40a, 40b Z-axis pulse motor 42a, 42b Spindle 44a, 44b Cutting blade 46a, 46b Camera unit 48 Cleaning Unit 50a, 50b Sub-chuck table 52a,52b Holding surface 54 Blade Cover 56 Housing 58 Cutting water supply unit 60 Cutting water

Claims

1. A cutting blade dressing method for dressing a cutting blade in a cutting device including a holding mechanism, a cutting unit having a rotatable cutting blade, a cutting water supply unit that supplies cutting water to a cutting area where cutting is performed by the cutting blade, and a processing feed unit that relatively feeds the holding mechanism and the cutting unit, a holding step of holding a dressing board containing abrasive grains with the holding mechanism; a dressing step in which the cutting blade is rotated, the cutting unit and the holding mechanism are relatively fed for processing by the processing feed unit, and the dressing board held by the holding mechanism is cut by the cutting blade while cutting water is supplied to the cutting area from the cutting water supply unit, The dressing method for a cutting blade is characterized in that, in the dressing process, the rotation speed of the cutting blade is set to 1000 rpm or more and 3000 rpm or less, the flow rate of the cutting water supplied from the cutting water supply unit is set to 10 mL / min or more and 50 mL / min or less, and the processing feed speed of the cutting unit and the holding mechanism is set to 100 mm / min or more and 500 mm / min or less.

2. A method for dressing a cutting blade as described in claim 1, characterized in that in the dressing process, the dressing board is cut with the cutting blade to disperse the abrasive grains contained in the dressing board into the cutting water that accumulates on the dressing board, and the cutting blade is brought into contact with the abrasive grains contained in the cutting water.

3. A dressing method for dressing a cutting blade in a cutting device including a holding mechanism, a cutting unit having a rotatable cutting blade, a cutting water supply unit for supplying cutting water to a cutting area where cutting is performed by the cutting blade, and a processing feed unit for processing-feeding the holding mechanism and the cutting unit relatively, comprising: a holding step of holding a dressing board containing abrasive grains with the holding mechanism; a dressing step in which the cutting blade is rotated, the cutting unit and the holding mechanism are relatively fed for processing by the processing feed unit, and the dressing board held by the holding mechanism is cut by the cutting blade while cutting water is supplied to the cutting area from the cutting water supply unit, In the dressing process, the flow rate of the cutting water supplied from the cutting water supply unit is set to 10 mL / min or more and 50 mL / min or less, and the dressing board is cut with the cutting blade to disperse the abrasive grains contained in the dressing board into the cutting water that accumulates on the dressing board, and the cutting blade is brought into contact with the abrasive grains contained in the cutting water, which is a method for dressing a cutting blade.

4. 4. The cutting blade dressing method according to claim 1, wherein the holding mechanism is a chuck table capable of holding a workpiece or a sub-chuck table not capable of holding a workpiece.

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