Dressing tool and dressing method

Abstract

To provide a dressing tool capable of not only dressing the lower surface (ground surface) of a grindstone included in a grinding wheel but also the outside thereof.SOLUTION: One of a first dressing part used for dressing the lower surface of a grindstone and a second dressing part used for dressing the outside of the grindstone is provided so that an upper surface can be lower than the other of the first and second dressing part and an outer peripheral end can be positioned outside. By using this dressing tool, dressing of the lower surface and the outside of the grindstone can be carried out at different times or at the same time.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a dressing tool used for dressing a grinding stone included in a grinding wheel, and a dressing method for dressing a grinding stone included in a grinding wheel using this dressing tool. [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, for example, by dividing a wafer on which a large number of devices are formed into regions containing individual devices.

[0003] Furthermore, wafers are often thinned before being divided in order to reduce the size and weight of chips. One method for thinning wafers is to grind the backside of the wafer using a grinding device. This grinding device includes, for example, a chuck table that holds the front side of the wafer, and a grinding unit that is provided above the chuck table and has a spindle with a grinding wheel attached to its lower end (see, for example, Patent Document 1).

[0004] A grinding wheel generally includes a plurality of grinding stones, each of which has a rectangular parallelepiped shape and is arranged in a circular pattern. The grinding stones have abrasive grains such as diamond or cubic boron nitride (cBN) dispersed in a binder such as a vitrified bond or resin bond. Furthermore, the grinding wheel generally includes a grinding water supply nozzle for supplying a liquid (grinding water) such as pure water.

[0005] When thinning a wafer in the grinding device, both the chuck table and the spindle are rotated, and grinding water is supplied to the backside of the wafer from the grinding water supply nozzle, while the backside of the wafer is brought into contact with the grinding surfaces of the grinding wheels. This allows the backside of the wafer to be ground by the abrasive grains exposed on the lower surfaces (grinding surfaces) of the grinding wheels, thereby thinning the wafer.

[0006] In addition, new (unused) grinding wheels may not have enough abrasive grains exposed on their undersides. Furthermore, in grinding wheels, the undersides of multiple grinding wheels may not be uniform, i.e., may not be located on the same plane. In these cases, the wafer grinding efficiency may decrease.

[0007] Therefore, in a grinding device, prior to grinding a wafer, a process (underside dressing) is often performed in which the underside of each of a plurality of grinding wheels is ground to sufficiently expose the abrasive grains on the underside and the undersides are aligned. Such underside dressing of the grinding wheels is performed, for example, by bringing the undersides of the plurality of grinding wheels into contact with the dressing portion of a dressing tool (dresser board) while rotating the grinding wheel (see, for example, Patent Document 2).

[0008] Furthermore, if the grinding debris generated by wafer grinding adheres to the underside of the grinding wheel, the abrasive grains may not be fully exposed on the underside of the grinding wheel (they may become clogged). Furthermore, repeated grinding may cause the exposed abrasive grains to wear down (they may become dull). In such cases, underside dressing of the grinding wheel may be performed. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-124690 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-142906 Summary of the Invention [Problem to be solved by the invention]

[0010] Grinding wheels are typically attached to the spindle of a grinding unit manually, which can result in the grinding wheel being attached to the spindle with its center misaligned with the axis of rotation of the spindle.

[0011] When the spindle is rotated in this state, it may vibrate in a direction perpendicular to the line that forms the spindle's rotation axis. If the backside of the wafer is ground by the multiple grinding stones of the grinding wheel that rotates with the spindle while the spindle is vibrating, the processing accuracy of the wafer may be reduced.

[0012] For example, in order to prevent the loss of rigidity that accompanies thinning by leaving the outer peripheral edge of the wafer, the backside of the wafer may be ground to form a recess on the backside of the wafer. This type of grinding is also called TAIKO grinding, and is performed by bringing the outer surface of the grinding wheel into contact with the outer peripheral edge of the wafer.

[0013] Here, if TAIKO grinding is performed while the spindle, to which the grinding wheel containing the grinding stone is attached at the tip, is vibrating, the outer edge of the remaining wafer cannot be made into the desired shape, i.e., the processing accuracy of the wafer decreases and the wafer becomes more likely to crack.

[0014] This type of deterioration in wafer processing accuracy can be suppressed by grinding the outer surfaces of the grinding wheels that are farthest from the line that forms the rotation axis of the spindle. Therefore, in order to suppress the deterioration in wafer processing accuracy, it is effective to perform a process (outer surface dressing) to align the outer surfaces of the multiple grinding wheels so that the distances between the center of the grinding wheel and the outer surfaces of each of the multiple grinding wheels are equal.

[0015] In view of the above, the object of the present invention is to provide a dressing tool that is capable of dressing not only the lower surface (grinding surface) of the grinding wheel included in a grinding wheel, but also its outer surface, and a dressing method that uses this dressing tool to dress both the lower surface and the outer surface of the grinding wheel. [Means for solving the problem]

[0016] According to one aspect of the present invention, there is provided a dressing tool used for dressing a grinding stone included in a grinding wheel, , th 1 Dressing section and , th and a support plate to which the first dressing part and the second dressing part are fixed, wherein one of the first dressing part and the second dressing part has a lower upper surface and an outer peripheral end portion positioned outward compared to the other of the first dressing part and the second dressing part, and the support plate is arranged such that its outer peripheral end portion is positioned outward compared to each of the first dressing part and the second dressing part. The support plate includes a disk-shaped main body portion and a disk-shaped protrusion portion that protrudes from the upper surface of the main body portion and has a diameter smaller than that of the main body portion, and the other of the first dressing portion and the second dressing portion is fixed to the upper surface of the protrusion portion, and one of the first dressing portion and the second dressing portion is fixed to the upper surface of the main body portion. A dressing tool is provided.

[0021] According to another aspect of the present invention, A dressing tool used for dressing a grinding stone included in a grinding wheel, comprising: a first dressing part used for dressing the underside of the grinding stone; a second dressing part used for dressing the outer surface of the grinding stone; and a support plate having the first dressing part and the second dressing part fixed to an upper surface thereof, wherein one of the first dressing part and the second dressing part has an upper surface lower than the other of the first dressing part and the second dressing part, and the support plate is arranged so that its outer peripheral end is positioned outward compared to each of the first dressing part and the second dressing part.A dressing method for dressing the grinding stone included in the grinding wheel using a dressing tool, the dressing method comprising: a holding step of holding the dressing tool on a holding surface of a chuck table that is rotatable about a rotation axis that is a straight line passing through the center of the holding surface; an attachment step of attaching the grinding wheel to a tip end portion of a spindle that extends along a first direction; and after the holding step and the attachment step, rotating the spindle and the chuck table in a state where a locus of the rotating grinding stone and the first dressing portion overlap in the first direction, the grinding wheel is dressed so that the lower surface of the grinding stone and the upper surface of the first dressing portion come into contact with each other. A dressing method is provided, comprising: an underside dressing step of dressing the underside of the grinding wheel by bringing the wheel and the chuck table closer together along the first direction; and an outer side dressing step of dressing the outer side of the grinding wheel by bringing the grinding wheel and the chuck table closer together along the second direction after the holding step and the mounting step, with the grinding wheel and the second dressing portion overlapping in a second direction perpendicular to the first direction, while rotating at least the grinding wheel. For example, in the dressing method of the present invention, the upper surface of the second dressing part may be higher than the upper surface of the first dressing part, and the outer peripheral edge of the first dressing part may be located outside the outer peripheral edge of the second dressing part. In this case, the support plate may include a disk-shaped main body part and a disk-shaped protrusion part protruding from the upper surface of the main body part and having a smaller diameter than the main body part, and the second dressing part may be fixed to the upper surface of the protrusion part, and the first dressing part may be fixed to the upper surface of the main body part. Alternatively, in the dressing method of the present invention, the upper surface of the first dressing part may be higher than the upper surface of the second dressing part, and the outer peripheral edge of the second dressing part may be located outside the outer peripheral edge of the first dressing part. In this case, the support plate may include a disk-shaped main body portion and a disk-shaped convex portion protruding from the upper surface of the main body portion and having a smaller diameter than the main body portion, and the first dressing portion may be fixed to the upper surface of the convex portion, and the second dressing portion may be fixed to the upper surface of the main body portion. [Effects of the Invention]

[0022] In the dressing tool of the present invention, one of the first dressing portion used for dressing the underside of the grinding wheel and the second dressing portion used for dressing the outer surface of the grinding wheel is provided so that its upper surface is lower and its outer peripheral end is positioned outward compared to the other of the first dressing portion and the second dressing portion, so that by using this dressing tool, it is possible to dress both the underside and outer surface of the grinding wheel at different times or simultaneously. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a partially cross-sectional side view that schematically shows an example of a grinding device. [Figure 2] FIG. 2(A) is a perspective view that schematically shows a first example of a dressing tool, and FIG. 2(B) is a cross-sectional view that schematically shows the first example of the dressing tool. [Figure 3] FIG. 3(A) is a perspective view that schematically shows an example of a grinding wheel, and FIG. 3(B) is a bottom view that schematically shows an example of a grinding wheel. [Figure 4] FIG. 4 is a flow chart that schematically illustrates an example of a dressing method. [Figure 5] FIG. 5 is a partial cross-sectional side view schematically showing an example of the grinding device after the holding step and the mounting step. [Figure 6] 6(A) and 6(B) are each a partial cross-sectional side view that schematically shows an example of the lower surface dressing step. [Figure 7] 7(A) and 7(B) are each a partial cross-sectional side view that schematically shows an example of the outer surface dressing step. [Figure 8] FIG. 8 is a partially cross-sectional side view that schematically shows how lower surface dressing and outer surface dressing are performed simultaneously. [Figure 9] FIG. 9(A) is a perspective view that schematically shows a second example of the dressing tool, and FIG. 9(B) is a cross-sectional view that schematically shows the second example of the dressing tool. [Figure 10] FIG. 10(A) is a perspective view that schematically shows a third example of the dressing tool, and FIG. 10(B) is a cross-sectional view that schematically shows the third example of the dressing tool. [Figure 11] 11(A) and 11(B) are each a partial cross-sectional side view that schematically shows another example of the lower surface dressing step. [Figure 12] 12(A) and 12(B) are each a partial cross-sectional side view schematically showing another example of the outer surface dressing step. [Figure 13] FIG. 13(A) is a perspective view that schematically shows a fourth example of the dressing tool, and FIG. 13(B) is a cross-sectional view that schematically shows the fourth example of the dressing tool. [Figure 14] FIG. 14(A) is a perspective view that schematically shows a fifth example of the dressing tool, and FIG. 14(B) is a cross-sectional view that schematically shows the fifth example of the dressing tool. [Figure 15] FIG. 15(A) is a perspective view that schematically shows a sixth example of the dressing tool, and FIG. 15(B) is a cross-sectional view that schematically shows the sixth example of the dressing tool. DETAILED DESCRIPTION OF THE INVENTION

[0024] An embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a partial cross-sectional side view showing a schematic diagram of an example of a grinding apparatus. Note that the X-axis direction and the Y-axis direction shown in Fig. 1 are directions perpendicular to each other on a horizontal plane, and the Z-axis direction is a direction (vertical direction) perpendicular to the X-axis direction and the Y-axis direction.

[0025] 1 has a base 4 that supports each of the components. A pair of guide rails 6, each extending along the X-axis direction, is provided on the upper surface of the base 4. A rectangular parallelepiped movable plate 8 is attached to the top of the pair of guide rails 6 in a manner that allows it to slide along the X-axis direction.

[0026] A screw shaft 10 extending along the X-axis direction is disposed between the pair of guide rails 6. A pulse motor 12 for rotating the screw shaft 10 is connected to one end of the screw shaft 10. A nut portion 14 for accommodating balls that circulate in response to the rotation of the screw shaft 10 is provided on the outer circumferential surface of the screw shaft 10 on which the threads are formed, thereby forming a ball screw.

[0027] Additionally, the nut portion 14 is fixed to the underside of the movable plate 8. Therefore, when the screw shaft 10 is rotated by the pulse motor 12, the movable plate 8 moves along the X-axis direction together with the nut portion 14. Additionally, a disk-shaped chuck table 16 that moves along the X-axis direction together with the movable plate 8 is provided on top of the movable plate 8.

[0028] The chuck table 16 has a disk-shaped frame 18 made of ceramics. A disk-shaped recess having a predetermined depth is formed on the upper surface of the frame 18. A flow path (not shown) that opens at the bottom of the recess is formed inside the frame 18. This flow path is also connected to a suction source (not shown) such as an ejector.

[0029] Furthermore, a circular porous plate 20 having a diameter roughly equal to that of a recess formed on the upper surface of the frame 18 is fixed to the recess. The porous plate 20 is made of, for example, porous ceramics. The porous plate 20 also has an upper surface (holding surface) 16a that has a shape corresponding to the side surface of a cone (a shape in which the center protrudes beyond the outer periphery).

[0030] When a suction source communicating with a flow path formed inside the frame 18 is operated, a suction force acts on the space near the upper surface of the porous plate 20. This allows a wafer, a dressing tool, or the like to be held on the holding surface 16a of the chuck table 16.

[0031] Fig. 2(A) is a perspective view showing an example of a dressing tool held on the holding surface 16a of the chuck table 16, and Fig. 2(B) is a cross-sectional view showing an example of a dressing tool held on the holding surface 16a of the chuck table 16. The dressing tool 1 shown in Fig. 2(A) and Fig. 2(B) includes a disk-shaped support plate 3.

[0032] The support plate 3 is made of, for example, polyvinyl chloride. A first dressing portion 5 used for dressing the lower surface (grinding surface) of a grinding wheel 58 (described later) and a second dressing portion 7 used for dressing the outer surface thereof are fixed to the upper surface of the support plate 3. For example, the first dressing portion 5 and the second dressing portion 7 are attached to the upper surface of the support plate 3 via a known adhesive.

[0033] The first dressing portion 5 has a cylindrical shape with an outer diameter that is shorter than the diameter of the support plate 3. The width of the first dressing portion 5 (the length in the radial direction of the support plate 3) is longer than the width of the grinding wheel 58 (the distance between the inner surface and the outer surface of the grinding wheel 58).

[0034] The second dressing portion 7 has a disk-like shape with a diameter roughly equal to the inner diameter of the first dressing portion 5, and is provided inside the first dressing portion 5. In other words, in the dressing tool 1, the outer peripheral end of the first dressing portion 5 is located outside the outer peripheral end of the second dressing portion 7.

[0035] Additionally, the upper surface of the second dressing portion 7 is located at a higher position than the upper surface of the first dressing portion 5. Furthermore, the first dressing portion 5 and the second dressing portion 7 are arranged so that the inner and outer peripheries of the first dressing portion 5 and the outer periphery of the second dressing portion 7 are concentric with the outer periphery of the support plate 3 in a plan view.

[0036] Each of the first dressing portion 5 and the second dressing portion 7 is formed by, for example, 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 a vitrified bond or a resin bond, and then firing the mixture.

[0037] The second dressing part 7 is preferably formed to have a higher hardness than the first dressing part 5. For example, the grain size of the abrasive grains contained in the first dressing part 5 is #3000 to #4000, and the grain size of the abrasive grains contained in the second dressing part 7 is #80 to #2000.

[0038] Specifically, in order to make the condition of the lower surface (grinding surface) of the grinding wheel 58 used for grinding wafers uniform, it is preferable that the grain size of the abrasive grains contained in the first dressing part 5 is small. On the other hand, in order to efficiently grind the outer surface side of the grinding wheel 58, it is preferable that the grain size of the abrasive grains contained in the second dressing part 7 is large.

[0039] 1, a rotary drive source 22 such as a pulse motor that rotates the chuck table 16 is provided below the chuck table 16. When the rotary drive source 22 operates, the chuck table 16 rotates around a rotation axis that is a straight line passing through the center of the holding surface 16a. This straight line passes through the center of the bottom of an imaginary cone having a side surface shaped to correspond to the holding surface 16a.

[0040] A cylindrical bearing 24 that rotatably supports the chuck table 16 is provided below the chuck table 16 and around the rotary drive source 22. The bearing 24 is supported by a cylindrical support plate 26.

[0041] Furthermore, fixed support mechanisms 28a, first movable support mechanisms 28b, and second movable support mechanisms 28c are provided below support plate 26 at approximately equal intervals along the circumferential direction of support plate 26. Fixed support mechanism 28a has a fixed shaft portion of a predetermined length. The upper portion of this fixed shaft portion is fixed to support plate 26, and the lower portion of the fixed shaft portion is fixed to movable plate 8.

[0042] Each of the first movable support mechanism 28b and the second movable support mechanism 28c has a movable shaft with a male thread formed on the upper part thereof. The upper part of each movable shaft is screwed into a threaded hole in the support plate 26, and the lower part of each movable shaft is supported by the moving plate 8 in a rotatable manner.

[0043] Furthermore, each movable shaft is connected to a pulse motor (not shown). When the movable shaft is rotated by this pulse motor, the portion of the support plate 26 near the screw hole that screws into the movable shaft rises or falls, thereby changing the inclination of the support plate 26.

[0044] Furthermore, when the inclination of the support plate 26 is changed, the inclination of the chuck table 16 is also changed. Therefore, in the grinding device 2, the inclination of the chuck table 16 can be adjusted by operating the first movable support mechanism 28b and the second movable support mechanism 28c.

[0045] A wall 30 extending in the Z-axis direction is provided on an end of the base 4. A pair of guide rails 32 each extending along the Z-axis direction is provided on the surface of the wall 30 facing the chuck table 16. A rectangular parallelepiped moving plate 34 is attached to the surface of the pair of guide rails 32 in a manner that allows it to slide along the Z-axis direction.

[0046] A screw shaft 36 extending along the Z-axis direction is disposed between the pair of guide rails 32. A pulse motor 38 for rotating the screw shaft 36 is connected to one end (upper end) of the screw shaft 36. A nut portion 40 for accommodating balls that circulate in response to the rotation of the screw shaft 36 is provided on the outer circumferential surface of the screw shaft 36 on which the threads are formed, thereby constituting a ball screw.

[0047] The nut portion 40 is fixed to the rear surface side of the movable plate 34. Therefore, when the screw shaft 36 is rotated by the pulse motor 38, the movable plate 34 moves along the Z-axis direction together with the nut portion 40. A grinding unit 44 is fixed to the front surface side of the movable plate 34 via a fixture 42.

[0048] The grinding unit 44 has a cylindrical spindle housing 46 extending along the Z-axis direction. A portion of a columnar spindle 48 is rotatably housed in the spindle housing 46. A rotation drive source (not shown), such as a pulse motor, is provided at the base end (upper end) of the spindle 48.

[0049] Furthermore, the tip (lower end) of the spindle 48 protrudes downward from the underside of the spindle housing 46, and a disk-shaped mount 50 is provided at this tip. A plurality of through holes (not shown) are formed at the outer circumferential end of this mount 50 at approximately equal intervals along the circumferential direction of the mount 50. A grinding wheel is attached to the mount 50, i.e., the tip of the spindle 48, using bolts inserted into each through hole.

[0050] Fig. 3(A) is a perspective view showing an example of a grinding wheel attached to the tip of the spindle 48, and Fig. 3(B) is a bottom view showing an example of a grinding wheel attached to the tip of the spindle 48. The grinding wheel 52 shown in Fig. 3(A) and Fig. 3(B) has a wheel base 54 having a cylindrical shape.

[0051] The wheel base 54 is made of a metal material such as stainless steel or aluminum, and its outer diameter is approximately equal to the diameter of the mount 50. A plurality of screw holes 56 that can be threadedly engaged with bolts are formed on the upper surface of the wheel base 54. As described above, each screw hole 56 is used when attaching the grinding wheel 52 to the mount 50.

[0052] A plurality of grinding wheels 58 are fixed to the underside of the wheel base 54 at approximately equal intervals along the circumferential direction of the wheel base 54. Each grinding wheel 58 has a shape like a rectangular parallelepiped curved along an arc. Each grinding wheel 58 has a bond material, such as a vitrified bond or resin bond containing pores, and abrasive grains, such as diamond or cubic boron nitride (cBN), dispersed in the bond material.

[0053] 4 is a flowchart schematically showing an example of a dressing method for dressing the grinding stone 58 included in the grinding wheel 52 using the dressing tool 1 in the grinding apparatus 2. In this method, first, the dressing tool 1 is held on the holding surface 16a of the chuck table 16 (holding step: S1), and the grinding wheel 52 is attached to the tip of the spindle 48 (attaching step: S2).

[0054] The order of the holding step (S1) and the mounting step (S2) is not limited. That is, the mounting step (S2) may be performed after the holding step (S1), or the holding step (S1) may be performed after the mounting step (S2). Figure 5 is a partial cross-sectional side view schematically showing an example of a grinding apparatus after the holding step (S1) and the mounting step (S2).

[0055] In this holding step (S1), first, the dressing tool 1 is loaded onto the chuck table 16 so that the center of the lower surface of the support plate 3 coincides with the center of the holding surface 16a of the chuck table 16. Then, a suction source communicating with a flow path formed inside the frame 18 of the chuck table 16 is operated to apply a suction force to the support plate 3 of the dressing tool 1.

[0056] As a result, the support plate 3 is elastically deformed to fit the holding surface 16a of the chuck table 16. That is, the lower surface of the support plate 3 assumes a shape corresponding to the side surface of the cone, and the holding surface 16a of the chuck table 16 is covered by the support plate 3. As a result, the dressing tool 1 is held on the holding surface 16a of the chuck table 16.

[0057] In the mounting step (S2), the grinding wheel 52 is first placed on the mount 50 so that the screw holes 56 are aligned with the through holes formed in the outer peripheral edge of the mount 50. Then, bolts (not shown) are threadedly engaged with the screw holes 56 via the through holes. This mounts the grinding wheel 52 to the tip of the spindle 48.

[0058] Next, the lower surface of the grinding wheel 58 is dressed (lower surface dressing step: S3), and the outer surface of the grinding wheel 58 is dressed (outer surface dressing step: S4). The order of the lower surface dressing step (S3) and the outer surface dressing step (S4) is not limited.

[0059] That is, the outer surface dressing step (S4) may be performed after the lower surface dressing step (S3), or the outer surface dressing step (S4) may be performed after the lower surface dressing step (S3).

[0060] 6(A) and 6(B) are partial cross-sectional side views each showing a schematic view of the underside dressing step (S3) performed using the dressing tool 1. In this underside dressing step (S3), first, the position of the chuck table 16 in the X-axis direction is adjusted so that the trajectory of the grinding wheel 58 rotating in accordance with the rotation of the spindle 48 overlaps with the first dressing part 5 in the Z-axis direction (first direction) (see FIG. 6(A)).

[0061] In this adjustment, it is necessary to overlap, in the Z-axis direction, a line segment that connects the inner edge and the outer edge of the upper surface of the first dressing part 5 over the shortest distance and that is perpendicular to the Z-axis direction with the locus of the rotating grinding wheel 58. In other words, it is necessary to overlap the coordinates of the line segment and the coordinates of the locus in a coordinate plane (XY coordinate plane) that is perpendicular to the Z-axis direction. Therefore, if necessary, the tilt of the chuck table 16 may be adjusted by operating the first movable support mechanism 28b and / or the second movable support mechanism 28c prior to this adjustment.

[0062] Then, while rotating the spindle 48 and the chuck table 16, the grinding wheel 52 and the chuck table 16 are moved closer to each other along the Z-axis direction so that the lower surface of the grinding stone 58 comes into contact with the upper surface of the first dressing section 5, i.e., the grinding wheel 52 is lowered (see FIG. 6(B)). As a result, the lower surface of the grinding stone 58 is dressed.

[0063] 7(A) and 7(B) are partial cross-sectional side views schematically illustrating the outer surface dressing step (S4) performed using the dressing tool 1. In this outer surface dressing step (S4), first, the position of the grinding wheel 52 in the Z-axis direction is adjusted so that the grinding stone 58 and the second dressing portion 7 overlap in the X-axis direction (second direction) (see FIG. 7(A)). Specifically, the position of the grinding wheel 52 in the Z-axis direction is adjusted so that the lower surface of the grinding stone 58 is positioned higher than the upper surface of the first dressing portion 5 and lower than the upper surface of the second dressing portion 7.

[0064] In this adjustment, it is necessary to overlap, in the X-axis direction, the grinding wheel 58 with a line segment that connects the lower end and upper end of the side surface of the second dressing portion 7 over the shortest distance and that extends linearly along the Z-axis direction. That is, it is necessary to overlap the coordinates of the line segment in a coordinate plane (YZ coordinate plane) that is orthogonal to the X-axis direction with the coordinates of the grinding wheel 58. Therefore, if necessary, prior to this adjustment, the tilt of the chuck table 16 may be adjusted by operating the first movable support mechanism 28b and / or the second movable support mechanism 28c.

[0065] Then, while rotating the spindle 48, the grinding wheel 52 and the chuck table 16 are moved closer to each other along the X-axis direction so that the outer surface of the grinding wheel 58 comes into contact with the side surface of the second dressing portion 7, i.e., the chuck table 16 is moved along the X-axis direction (see FIG. 7(B)). As a result, the outer surface of the grinding wheel 58 is dressed.

[0066] The outer surface of the grinding wheel 58 may be dressed while rotating the chuck table 16, i.e., while rotating the dressing tool 1. In this case, the underside and the outer surface of the grinding wheel 58 may be dressed simultaneously. Fig. 8 is a partially sectional side view that schematically shows how the underside and outer surface of the grinding wheel 58 are dressed simultaneously.

[0067] Specifically, while rotating the spindle 48 and the chuck table 16, the grinding wheel 52 is lowered so that the lower surface of the grinding wheel 58 contacts the upper surface of the first dressing portion 5, and the chuck table 16 is moved along the X-axis direction so that the outer surface of the grinding wheel 58 contacts the side surface of the second dressing portion 7. This allows the lower surface of the grinding wheel 58 and its outer surface to be dressed simultaneously.

[0068] As described above, in the dressing tool 1, the first dressing part 5 used for dressing the lower surface (grinding surface) of the grinding wheel 58 has an upper surface lower than that of the second dressing part 7 used for dressing the outer surface thereof, and is provided so that its outer peripheral end is positioned outward. Therefore, by using this dressing tool 1, it becomes possible to dress both the lower surface and the outer surface of the grinding wheel 58 at different times or simultaneously.

[0069] It should be noted that the dressing tool 1 is one embodiment of the dressing tool of the present invention, and the dressing tool of the present invention is not limited to the dressing tool 1. Fig. 9(A) is a perspective view schematically showing a second example of the dressing tool of the present invention, and Fig. 9(B) is a cross-sectional view schematically showing the second example of the dressing tool of the present invention.

[0070] 9(A) and 9(B) differs from the dressing tool 1 shown in FIG. 2(A) and 2(B) in that a protrusion is provided on the upper surface of the support plate. Specifically, the dressing tool 11 includes a support plate 13 made of, for example, polyvinyl chloride.

[0071] The support plate 13 has a disk-shaped main body 13a and a disk-shaped protrusion 13b that protrudes from the upper surface of the main body 13a and has a smaller diameter than the main body 13a. In addition, the support plate 13 is provided such that the outer peripheries of the main body 13a and the protrusion 13b are concentric in plan view.

[0072] A first dressing portion 15 is fixed to the upper surface of the main body 13a so as to surround the protrusion 13b. The first dressing portion 15 is used to dress the lower surface (grinding surface) of the grinding wheel 58. The first dressing portion 15 has the same shape as the first dressing portion 5 shown in Figures 2(A) and 2(B) and is made of the same material. The inner diameter of the first dressing portion 15 is approximately equal to the diameter of the protrusion 13b. The first dressing portion 15 is also provided so that its upper surface is approximately at the same height as the upper surface of the protrusion 13b.

[0073] Additionally, a second dressing portion 17 is fixed to the upper surface of the convex portion 13b and is used to dress the outer surface of the grinding wheel 58. This second dressing portion 17 is made of the same material as the second dressing portion 7 shown in Figures 2(A) and 2(B). Furthermore, the second dressing portion 17 has a disk-like shape whose diameter is approximately equal to the inner diameter of the first dressing portion 15, i.e., the diameter of the convex portion 13b.

[0074] In this dressing tool 11, the first dressing part 15 used for dressing the lower surface (grinding surface) of the grinding wheel 58 has an upper surface lower than that of the second dressing part 17 used for dressing the outer surface thereof, and is provided so that its outer peripheral end is positioned outward. Therefore, by using this dressing tool 11, it becomes possible to dress both the lower surface and the outer surface of the grinding wheel 58 at different times or simultaneously, similar to the case where the dressing tool 1 shown in Figures 2(A) and 2(B) is used.

[0075] Fig. 10(A) is a perspective view schematically showing a third example of the dressing tool of the present invention, and Fig. 10(B) is a cross-sectional view schematically showing the third example of the dressing tool of the present invention. In short, the dressing tool 21 shown in Fig. 10(A) and Fig. 10(B) differs from the dressing tool 1 shown in Fig. 2(A) and Fig. 2(B) in that the positions of the first dressing part and the second dressing part are interchanged.

[0076] Specifically, this dressing tool 21 has a support plate 23 that has a shape similar to that of the support plate 3 shown in Figures 2(A) and 2(B) and is made of the same material. A first dressing part 25 used for dressing the lower surface (grinding surface) of the grinding wheel 58 and a second dressing part 27 used for dressing the outer surface thereof are fixed to the upper surface of this support plate 23. For example, the first dressing part 25 and the second dressing part 27 are attached to the upper surface of the support plate 23 via a known adhesive.

[0077] The first dressing portion 25 has a disk shape with a diameter smaller than the diameter of the support plate 23. The diameter of the first dressing portion 25 is also larger than the width of the grinding wheel 58 (the distance between the inner and outer surfaces of the grinding wheel 58).

[0078] The second dressing portion 27 has a cylindrical shape with an outer diameter shorter than the diameter of the support plate 23 and an inner diameter roughly equal to the diameter of the first dressing portion 25, and is arranged so that its inner surface comes into contact with the side surface of the first dressing portion 25. In other words, in the dressing tool 21, the outer peripheral end of the second dressing portion 27 is located outside the outer peripheral end of the first dressing portion 25.

[0079] The upper surface of the first dressing part 25 is located at a higher position than the upper surface of the second dressing part 27. Furthermore, the first dressing part 25 and the second dressing part 27 are provided so that the outer periphery of the first dressing part 25 and the inner and outer peripheries of the second dressing part 27 are concentric with the outer periphery of the support plate 23 in a plan view.

[0080] Furthermore, the first dressing part 25 is made of the same material as the first dressing part 5 shown in Figures 2(A) and 2(B), and the second dressing part 27 is made of the same material as the second dressing part 7 shown in Figures 2(A) and 2(B).

[0081] 11(A) and 11(B) are partial cross-sectional side views each showing a schematic view of the underside dressing step (S3) performed using the dressing tool 21. In this underside dressing step (S3), first, the position of the chuck table 16 in the X-axis direction is adjusted so that the trajectory of the grinding wheel 58 rotating in accordance with the rotation of the spindle 48 overlaps with the first dressing portion 25 in the Z-axis direction (first direction) (see FIG. 11(A)).

[0082] In this adjustment, it is necessary to overlap, in the Z-axis direction, the line segment that connects the center and outer periphery of the upper surface of the first dressing portion 25 over the shortest distance and that is perpendicular to the Z-axis direction with the locus of the rotating grinding wheel 58. In other words, it is necessary to overlap the coordinates of the line segment and the coordinates of the locus in a coordinate plane (XY coordinate plane) that is perpendicular to the Z-axis direction. Therefore, if necessary, the tilt of the chuck table 16 may be adjusted by operating the first movable support mechanism 28b and / or the second movable support mechanism 28c prior to this adjustment.

[0083] Then, while rotating the spindle 48 and the chuck table 16, the grinding wheel 52 and the chuck table 16 are brought closer together along the Z-axis direction so that the lower surface of the grinding stone 58 comes into contact with the upper surface of the first dressing portion 25, i.e., the grinding wheel 52 is lowered (see FIG. 11(B)). As a result, the lower surface of the grinding stone 58 is dressed.

[0084] 12(A) and 12(B) are partial cross-sectional side views schematically illustrating the outer surface dressing step (S4) performed using the dressing tool 21. In this outer surface dressing step (S4), first, the position of the grinding wheel 52 in the Z-axis direction is adjusted so that the grinding stone 58 and the second dressing portion 27 overlap in the X-axis direction (second direction) (see FIG. 12(A)). Specifically, the position of the grinding wheel 52 in the Z-axis direction is adjusted so that the lower surface of the grinding stone 58 is positioned higher than the upper surface of the support plate 23 and lower than the upper surface of the second dressing portion 27.

[0085] In this adjustment, it is necessary to overlap, in the X-axis direction, the grinding wheel 58 with a line segment that connects the lower end and upper end of the side surface of the second dressing portion 27 over the shortest distance and that extends linearly along the Z-axis direction. That is, it is necessary to overlap the coordinates of the line segment in a coordinate plane (YZ coordinate plane) that is orthogonal to the X-axis direction with the coordinates of the grinding wheel 58. Therefore, if necessary, prior to this adjustment, the tilt of the chuck table 16 may be adjusted by operating the first movable support mechanism 28b and / or the second movable support mechanism 28c.

[0086] Then, while rotating the spindle 48, the grinding wheel 52 and the chuck table 16 are moved closer to each other along the X-axis direction so that the outer surface of the grinding wheel 58 comes into contact with the side surface of the second dressing portion 27, i.e., the chuck table 16 is moved along the X-axis direction (see FIG. 12(B)). As a result, the outer surface of the grinding wheel 58 is dressed.

[0087] As described above, in the dressing tool 21, the second dressing part 27 used to dress the outer surface of the grinding wheel 58 has an upper surface lower and an outer peripheral end positioned outward compared to the first dressing part 25 used to dress the lower surface (grinding surface) of the second dressing part 27. Therefore, by using this dressing tool 21, it becomes possible to dress both the lower surface and the outer surface of the grinding wheel 58 at different times.

[0088] Fig. 13(A) is a perspective view schematically showing a fourth example of the dressing tool of the present invention, and Fig. 13(B) is a cross-sectional view schematically showing the fourth example of the dressing tool of the present invention. In short, the dressing tool 31 shown in Fig. 13(A) and Fig. 13(B) differs from the dressing tool 21 shown in Fig. 10(A) and Fig. 10(B) in that a protrusion is provided on the upper surface of the support plate.

[0089] Specifically, the dressing tool 31 includes a support plate 33 made of, for example, polyvinyl chloride. The support plate 33 has a disk-shaped main body 33a and a disk-shaped protrusion 33b that protrudes from the upper surface of the main body 33a and has a smaller diameter than the main body 33a. The support plate 33 is provided with the main body 33a and the protrusion 33b so that their outer peripheries are concentric in plan view.

[0090] A first dressing portion 35 is fixed to the upper surface of the protrusion 33b and is used to dress the lower surface of the grinding wheel 58. This first dressing portion 35 is made of the same material as the second dressing portion 7 shown in Figures 2(A) and 2(B). Furthermore, the first dressing portion 35 has a disk-like shape with a diameter that is approximately equal to the diameter of the protrusion 33b.

[0091] A second dressing portion 37, which is used to dress the outer surface of the grinding wheel 58, is fixed to the upper surface of the main body portion 33a so as to surround the convex portion 33b. This second dressing portion 37 has the same shape as the second dressing portion 27 shown in Figures 10(A) and 10(B) and is made of the same material. Furthermore, the inner diameter of the second dressing portion 27 is approximately equal to the diameter of the convex portion 33b, i.e., the diameter of the first dressing portion 35. The second dressing portion 37 is also provided so that its upper surface is approximately at the same height as the upper surface of the convex portion 33b.

[0092] In this dressing tool 31, the second dressing part 37 used to dress the outer surface of the grinding wheel 58 has an upper surface lower than that of the first dressing part 35 used to dress the lower surface (grinding surface) of the grinding wheel 58, and is provided so that its outer peripheral end is positioned outward. Therefore, by using this dressing tool 31, it is possible to dress both the lower surface and the outer surface of the grinding wheel 58 at different times.

[0093] Fig. 14(A) is a perspective view schematically showing a fifth example of the dressing tool of the present invention, and Fig. 14(B) is a cross-sectional view schematically showing the fifth example of the dressing tool of the present invention. In short, the dressing tool 41 shown in Fig. 14(A) and Fig. 14(B) differs from the dressing tool 21 shown in Fig. 10(A) and Fig. 10(B) in that the shape of the second dressing portion is different.

[0094] Specifically, this dressing tool 41 has a support plate 43 that has a shape similar to that of the support plate 23 shown in Figures 10(A) and 10(B) and is made of the same material. On the upper surface of this support plate 43, a first dressing part 45 used for dressing the lower surface (grinding surface) of the grinding wheel 58 and a second dressing part 47 used for dressing the outer surface thereof are fixed.

[0095] The first dressing part 45 has the same shape as the first dressing part 25 shown in Figures 10(A) and 10(B) and is made of the same material. The second dressing part 47 has a shape like a rectangular parallelepiped curved along an arc, and is arranged so that its inner surface comes into contact with the side surface of the first dressing part 25.

[0096] That is, in the dressing tool 41, the outer peripheral end of the second dressing portion 47 is located outside the outer peripheral end of the first dressing portion 45. Furthermore, the second dressing portion 47 is made of the same material as the second dressing portion 7 shown in Figures 2(A) and 2(B).

[0097] In this dressing tool 41, the second dressing part 47 used for dressing the outer surface of the grinding wheel 58 has an upper surface lower than that of the first dressing part 45 used for dressing the lower surface (grinding surface) of the second dressing part 47, and is provided so that its outer peripheral end is positioned outward. Therefore, by using this dressing tool 41, it becomes possible to dress both the lower surface and the outer surface of the grinding wheel 58 at different times.

[0098] Figure 15(A) is a perspective view schematically showing a sixth example of the dressing tool of the present invention, and Figure 15(B) is a cross-sectional view schematically showing the sixth example of the dressing tool of the present invention. In short, the dressing tool 51 shown in Figures 15(A) and 15(B) differs from the dressing tool 21 shown in Figures 10(A) and 10(B) in that the first dressing portion and the second dressing portion are separated from each other.

[0099] Specifically, this dressing tool 51 has a support plate 53 that has a shape similar to that of the support plate 23 shown in Figures 10(A) and 10(B) and is made of the same material. A first dressing part 55 used for dressing the lower surface (grinding surface) of the grinding wheel 58 and a second dressing part 57 used for dressing the outer surface thereof are fixed to the upper surface of this support plate 53.

[0100] The first dressing portion 55 has a shape similar to that of the first dressing portion 25 shown in Figures 10(A) and 10(B) and is made of the same material. The second dressing portion 57 has a cylindrical shape with an outer diameter shorter than the diameter of the support plate 53 and an inner diameter longer than that of the first dressing portion 55, and is provided so as to surround the first dressing portion 55. That is, in the dressing tool 51, the outer peripheral end of the second dressing portion 57 is located outside the outer peripheral end of the first dressing portion 55.

[0101] The upper surface of the first dressing part 55 is located higher than the upper surface of the second dressing part 57. Furthermore, the first dressing part 55 and the second dressing part 57 are arranged so that the outer periphery of the first dressing part 55 and the inner and outer peripheries of the second dressing part 57 are concentric with the outer periphery of the support plate 53 in a plan view. Furthermore, the second dressing part 57 is made of the same material as the second dressing part 7 shown in Figures 2(A) and 2(B).

[0102] In this dressing tool 51, the second dressing part 57 used for dressing the outer surface of the grinding wheel 58 has an upper surface lower and an outer peripheral end positioned outward compared to the first dressing part 55 used for dressing the lower surface (grinding surface) of the second dressing part 57. Therefore, by using this dressing tool 51, it becomes possible to dress both the lower surface and the outer surface of the grinding wheel 58 at different times.

[0103] 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]

[0104] 1: Dressing tool 2: Grinding equipment 3: Support plate 4: Base 5: First dressing section 6: Guide rail 7: Second dressing section 8: Moving plate 10: Screw shaft 11: Dressing tool 12: Pulse motor 13: Support plate (13a: main body, 13b: protrusion) 14: Nut part 15: First dressing section 16: Chuck table 17: Second dressing section 18:Frame body 20: Porous plate 21: Dressing tool 22: Rotation drive source 23: Support plate 24: Bearing 25: First dressing section 26: Support plate 27: Second dressing section 28a: Fixed support mechanism 28b: First movable support mechanism 28c: Second movable support mechanism 30: Wall 31: Dressing tool 32: Guide rail 33: Support plate (33a: main body, 33b: protrusion) 34: Moving plate 35: First dressing section 36: Screw shaft 37: Second dressing section 38: Pulse motor 40: Nut part 41: Dressing tool 42:Fixed part 43: Support plate 44: Grinding unit 45: First dressing section 46: Spindle housing 47: Second dressing section 48: Spindle 50: Mount 51: Dressing tool 52: Grinding wheel 53: Support plate 54: Wheel base 55: First dressing section 56: Screw hole 57: Second dressing section 58: Grinding wheel

Claims

1. A dressing tool used to dress a grinding stone included in a grinding wheel, a first dressing portion; a second dressing portion; and a support plate having the first dressing portion and the second dressing portion fixed to an upper surface thereof; one of the first dressing portion and the second dressing portion is provided so that its upper surface is lower and its outer peripheral end portion is positioned outward compared to the other of the first dressing portion and the second dressing portion; the support plate is provided such that an outer peripheral end portion thereof is positioned outward compared with each of the first dressing portion and the second dressing portion; The support plate includes a disk-shaped main body portion and a disk-shaped protrusion portion that protrudes from an upper surface of the main body portion and has a diameter smaller than that of the main body portion, the other of the first dressing portion and the second dressing portion is fixed to an upper surface of the convex portion; A dressing tool, wherein one of the first dressing portion and the second dressing portion is fixed to the top surface of the body portion.

2. A dressing tool used to dress a grinding stone included in a grinding wheel, a first dressing portion used for dressing the lower surface of the grinding wheel; a second dressing portion used to dress the outer surface of the grinding wheel; a support plate having the first dressing portion and the second dressing portion fixed to an upper surface thereof; one of the first dressing portion and the second dressing portion is provided so that its upper surface is lower and its outer peripheral end portion is positioned outward compared to the other of the first dressing portion and the second dressing portion; a dressing method for dressing the grinding stone included in the grinding wheel by using the dressing tool, wherein the support plate is provided so that an outer peripheral end portion thereof is positioned outward compared with each of the first dressing portion and the second dressing portion, a holding step of holding the dressing tool on a holding surface of a chuck table that is rotatable about a rotation axis that is a straight line passing through the center of the holding surface; a mounting step of mounting the grinding wheel on a tip end of a spindle extending along a first direction; a bottom surface dressing step, after the holding step and the mounting step, of dressing the bottom surface of the grinding wheel by bringing the grinding wheel and the chuck table closer together along the first direction so that the bottom surface of the grinding wheel and the top surface of the first dressing portion come into contact with each other while rotating the spindle and the chuck table in a state where a locus of the rotating grinding wheel and the first dressing portion overlap in the first direction; an outer surface dressing step of dressing the outer surface of the grinding wheel by bringing the grinding wheel and the chuck table closer together along the second direction so that the outer surface of the grinding wheel and the side of the second dressing portion come into contact with each other while rotating at least the grinding wheel, with the grinding wheel and the second dressing portion overlapping in a second direction perpendicular to the first direction, after the holding step and the mounting step; A dressing method comprising:

3. The upper surface of the second dressing portion is located higher than the upper surface of the first dressing portion, 3. The dressing method according to claim 2, wherein the outer peripheral edge of the first dressing portion is located outside the outer peripheral edge of the second dressing portion.

4. The support plate includes a disk-shaped main body portion and a disk-shaped protrusion portion protruding from an upper surface of the main body portion and having a diameter smaller than that of the main body portion; the second dressing portion is fixed to an upper surface of the protrusion, 4. The dressing method according to claim 3, wherein the first dressing part is fixed to the upper surface of the main body part.

5. The upper surface of the first dressing portion is located higher than the upper surface of the second dressing portion, 3. The dressing method according to claim 2, wherein the outer peripheral edge of the second dressing portion is located outside the outer peripheral edge of the first dressing portion.

6. The support plate includes a disk-shaped main body portion and a disk-shaped protrusion portion protruding from an upper surface of the main body portion and having a diameter smaller than that of the main body portion; the first dressing portion is fixed to an upper surface of the protrusion, 6. The dressing method according to claim 5, wherein the second dressing portion is fixed to the upper surface of the main body portion.

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