JP7351611B2 - Wafer chamfer processing equipment - Google Patents

Description

The present invention relates to a wafer chamfering device.

When manufacturing a wafer with a flat surface in a semiconductor wafer manufacturing process, for example, a cylindrical ingot made of a raw material such as silicon is sliced thinly with a wire saw or the like to obtain a disk-shaped wafer. In order to prevent the edges of the sliced wafers from chipping or cracking, the edges are chamfered.
That is, for example, as disclosed in Patent Documents 1, 2, or 3, a rotating chamfering process is performed using a disc-shaped chamfering grindstone that has a V-shaped or U-shaped recess formed on the outer peripheral side surface and is thicker than the thickness of the wafer. Chamfering is performed by bringing the edge of the wafer into contact with the recess of the grindstone.

Japanese Patent Application Publication No. 08-090401 Japanese Patent Application Publication No. 11-347901 Japanese Patent Application Publication No. 2005-153085

As the chamfering whetstone, a resin bonded whetstone in which abrasive grains are bonded with resin is used to soften the impact of the abrasive grains when the chamfering whetstone comes into contact with the wafer W. However, resin bonded grindstones are prone to wear and the concave shape on the outer circumferential side surface tends to collapse. Then, there is a problem that the wafer edge cannot be chamfered normally due to the concave shape of the chamfering grindstone being distorted. Therefore, it is necessary to periodically correct the concave shape of the chamfering grindstone using a truing grindstone. Note that using a metal bonded grindstone as the chamfering grindstone is less likely to wear out and the concave shape is less likely to deform, but since the metal bond is hard, the impact of the abrasive grains that come into contact with the wafer will cause a lot of chipping on the wafer, so it is not suitable.

The truing whetstone that forms a dent on the outer peripheral side of a chamfered whetstone or corrects the shape of the dent formed on the outer periphery side uses a metal bonded whetstone that does not easily wear out even when grinding a chamfered whetstone. A convex shape similar to the cross section of the chamfered wafer is formed around the circumference, and by transferring the convex shape to the chamfering grindstone, a recess is formed in the chamfering grindstone.

However, since the truing whetstone also wears, the convex shape is deformed, making it impossible to form a concavity or correct the shape of the concavity with the chamfering whetstone. Therefore, in order to replace the truing whetstone or correct the convex shape of the truing whetstone, it becomes necessary to stop the chamfering device, resulting in a problem that the productivity of chamfering decreases.

Therefore, in a wafer chamfering apparatus, there is a problem of preventing a situation in which chamfering productivity is reduced by replacing the truing grindstone or correcting the convex shape of the truing grindstone.

In order to solve the above problems, the present invention has a holding means that holds a wafer and has a holding surface having a diameter smaller than the wafer diameter and is rotatable about a rotation axis extending in the Z-axis direction perpendicular to the holding surface. , a chamfering means for chamfering the edge by bringing a recess on the outer surface of a rotatable chamfering whetstone into contact with the edge of the wafer held by the holding means, the chamfering whetstone truing means for forming a recess on the outer surface of the truing means, and an X-axis moving means for relatively moving the chamfering means and the truing means in an X-axis direction parallel to the holding surface, the chamfering means , a disc-shaped chamfering whetstone that is thicker than the thickness of the wafer, and a first spindle having the chamfering whetstone attached to its tip and rotating the chamfering whetstone about an axis parallel to the rotation axis of the holding means. The truing means includes a disc-shaped truing grindstone that is thinner than the chamfered grindstone or has a sharp outer peripheral tip, and a second spindle to which the truing grindstone is fixed, and An angle changing means for changing the inclination angle of the second spindle, the angle changing means changing the Y-axis perpendicular to the X-axis direction and the Z-axis direction of the second spindle with respect to the first spindle. After changing the inclination angle in the direction side, the chamfering grindstone and the truing grindstone are moved in a direction in which they approach each other relatively to each other by the X-axis moving means, and the dent is formed on the outer surface of the chamfering grindstone. This is a chamfering device.

The wafer chamfer processing apparatus according to the present invention includes a concave shape measuring sensor that measures the shape of the concave of the chamfering grindstone, and a convex shape memory unit that memorizes the convex shape of the cross section of the edge of the wafer that has been chamfered. , a Z-axis moving means for relatively moving the chamfering means and the truing means in the Z-axis direction, and a concave shape measuring sensor that measures the convex shape stored in the convex shape memory section. It is preferable to include a control means for controlling the angle changing means, the X-axis moving means, and the Z-axis moving means when forming the recess so that the shapes of the recesses are combined.

The wafer chamfer processing apparatus according to the present invention includes a holding means that has a holding surface having a diameter smaller than the diameter of the wafer that holds the wafer and is rotatable around the center of the holding surface, and a holding means that rotates around the edge of the wafer held by the holding means. A chamfering means for chamfering the edge by bringing the recesses on the outer surface of the chamfering grindstone into contact with each other; a truing means for forming a recess on the outer surface of the chamfering grindstone; The chamfering means includes a disc-shaped chamfering grindstone that is thicker than the thickness of the wafer, and a chamfering grindstone attached to the tip and rotated to move the chamfering grindstone along the Z-axis perpendicular to the holding surface. a first spindle extending in the direction, and the truing means includes a disc-shaped truing grindstone that is thinner than the chamfered grindstone or has a pointed outer peripheral tip (i.e., a thinner truing grindstone than the conventional one); a second spindle extending parallel to the spindle, the second spindle is tilted at a predetermined angle in the Y-axis direction perpendicular to the X-axis direction and the Z-axis direction with respect to the first spindle; By moving the chamfering whetstone and the truing whetstone relatively toward each other using the X-axis moving means and forming a dent (approximately U-shaped dent) on the outer surface of the chamfering whetstone, it is possible to prevent the truing whetstone from wearing out when the truing whetstone becomes worn. Even if there is, by changing the angle of the truing grindstone, it is possible to form a substantially U-shaped recess on the outer surface of the chamfering grindstone. Therefore, there is no need to dress or frequently replace the truing grindstone, so there is no need to stop the chamfering apparatus for the above-mentioned work, and the productivity of wafer chamfering does not decrease.

The wafer chamfer processing apparatus according to the present invention includes angle changing means for changing the inclination angle of the second spindle with respect to the first spindle, so that the second spindle is aligned with respect to the first spindle in the X-axis direction. It becomes easier to incline by a predetermined angle toward the Y-axis direction that is perpendicular to the Z-axis direction.

A wafer chamfer processing apparatus according to the present invention includes a concave shape measuring sensor that measures the shape of a concave of a chamfering grindstone, a convex shape memory unit that memorizes a convex shape of a cross section of a chamfered edge of a wafer, and a Z. The Z-axis moving means relatively moves the chamfering means and the truing means in the axial direction, and the concavity of the chamfering grindstone measured by the concavity shape measurement sensor with respect to the convexity shape of the wafer memorized by the convexity shape memory section. By providing a control means for controlling the angle changing means, the X-axis moving means, and the Z-axis moving means when forming the recess so that the shapes merge, the shape of the recess can always be made into a desired shape. It becomes possible.

FIG. 1(A) is a front view of an example of a wafer chamfer processing apparatus viewed from the Y-axis direction. FIG. 1(B) is a side view of an example of a wafer chamfer processing apparatus viewed from the X-axis direction. It is a sectional view showing an example of dimensions of a truing grindstone. FIG. 3(A) is a front view of another example of the wafer chamfering processing apparatus viewed from the Y-axis direction. FIG. 3(B) is a side view of another example of the wafer chamfering processing apparatus viewed from the X-axis direction. FIG. 2 is a schematic cross-sectional view illustrating a state in which an arc-shaped portion is formed in a recess of a chamfering grindstone. It is a typical sectional view explaining the state where a linear taper part is formed in the recess of a chamfering grindstone.

(Embodiment 1)
The wafer W chamfering apparatus 1 shown in FIGS. 1A and 1B has a holding surface 30a that holds a wafer W and has a smaller diameter than the wafer diameter. a chamfering means 6 for chamfering the edge Wd by bringing a recess 63a on the outer surface of a rotatable chamfering grindstone 63 into contact with the edge Wd of the wafer W held by the holding means 30; It is equipped with As shown in FIGS. 1A and 1B, the above-mentioned components of the chamfering device 1 are housed, for example, inside a rectangular parallelepiped casing 10 of the chamfering device 1. becomes the processing room.

The wafer W is, for example, a circular small-diameter wafer manufactured by hollowing out a large-diameter wafer on which no devices are formed using a core drill, but is not limited thereto. The wafer W may be, for example, a circular wafer manufactured by slicing a cylindrical silicon ingot with a wire saw.

The holding means 30 has, for example, a cylindrical outer shape, and, for example, its upper end to middle part is rotatably housed within the housing 10, and the lower end protrudes outside from the bottom plate of the housing 10. ing. A suction path 300 is formed inside the holding means 30 so as to extend in the Z-axis direction, and the upper end of the suction path 300 is open at a holding surface 30a that is the upper surface of the holding means 30. The holding surface 30a is a flat surface substantially parallel to the horizontal plane (X-axis and Y-axis plane). The lower end side of the suction path 300 curves radially outward inside the holding means 30 and opens at the outer peripheral surface of the holding means 30 .

For example, a flat plate-shaped mounting shelf 181 having approximately the same length as the housing 10 is attached to the bottom surface of the housing 10 via a bracket 180. A support means 31 having a plate-like outer shape and having a bearing 310 inside is attached to the mounting shelf 181, and the support means 31 allows the holding means 30 to rotate around the axis in the Z-axis direction (vertical direction). I support it.

The lower end of the holding means 30 is surrounded by a rotary joint 33, and the lower end of the suction path 300 communicates via the rotary joint 33 with a suction source 39 such as an ejector or a vacuum generator. The rotary joint 33 plays the role of transmitting the suction force generated by the suction source 39 to the suction path 300 of the rotating holding means 30 without fail.
A shaft (not shown) of a motor 35 is connected to the lower end of the holding means 30, and the motor 35 allows the holding means 30 to rotate around an axis in the Z-axis direction.

Above the holding means 30, a wafer fixing means 34 made of an air cylinder or an electric cylinder is arranged. The wafer fixing means 34 includes, for example, a cylinder tube 340 that includes a piston (not shown) inside and extends in the Z-axis direction, and a piston rod 341 that is inserted into the cylinder tube 340 and whose upper end is attached to the piston. The lower end surface of the piston rod 341 that contacts the wafer W is finished smoothly, and the end (ridgeline) of the lower end surface may be chamfered so as not to damage the wafer W.

Inside the housing 10, the holding means 30, a chamfering means 6 having a chamfering grindstone 63, and a truing means 7 for forming a recess 63a on the outer surface of the chamfering grindstone 63 are arranged side by side in order from the +X direction side. It is set up.

Inside the housing 10, an X-axis moving means 15 is disposed for relatively moving the chamfering means 6 and the truing means 7 in the X-axis direction parallel to the holding surface 30a of the holding means 30. The X-axis moving means 15 includes a base 159 fixed to the inner wall surface of the casing 10, a horizontal ball screw 150 provided on the base 159 in parallel to the X-axis direction, and a pair of horizontal movement means extending in the X-axis direction. A motor 152 for rotationally driving a horizontal ball screw 150, and a movable plate 153 whose internal nut is screwed into the horizontal ball screw 150 and whose side surface is in sliding contact with the guide rail 151. Then, as the motor 152 rotates the horizontal ball screw 150, the chamfering means 6 fixed to the movable plate 153 via the Z-axis moving means 17 (only a part of which is shown in FIG. 1(A)) moves to the guide rail. 151 to move in the X-axis direction.

The Z-axis moving means 17 shown in FIG. 1(B) relatively moves the chamfering means 6 and the truing means 7 in the Z-axis direction. That is, the Z-axis moving means 17 includes a pair of support plates 179 fixed above and below the movable plate 153, a vertical ball screw 170 supported by the pair of support plates 179 so as to be parallel to the Z-axis direction, and a vertical ball screw. 170, a guide rail 171 extending in the Z-axis direction, and a movable member 173 whose internal nut is screwed onto the vertical ball screw 170 and whose side surface is in sliding contact with the guide rail 171. When the vertical ball screw 170 is rotated by the drive of the motor 172, the movable member 173 supporting the chamfering means 6 is guided by the guide rail 171 and moves in the Z-axis direction.
Note that the truing means 7 may be reciprocally movable in the Z-axis direction by a Z-axis moving means, or the chamfering device 1 may not include the Z-axis moving means 17 and the truing grindstone 70 and the chamfering grindstone 63 may be moved relative to each other. A configuration in which the height relationship is fixed may also be used.

The chamfering means 6 includes a disc-shaped chamfering grindstone 63 that is thicker than the thickness of the wafer W, and the chamfering grindstone 63 is attached to the tip (lower end) and rotated to extend in the Z-axis direction perpendicular to the holding surface 30a of the holding means 30. The first spindle 61 is provided with at least a first spindle 61.
The first spindle 61 is, for example, rotatably supported by a housing 62 that includes an air bearing mechanism inside and has a cylindrical outer shape. A motor 64 is connected to the first spindle 61, and the first spindle 61 is rotatable around an axis in the Z-axis direction by the motor 64. The outer surface of the housing 62 is fixed to the movable member 173.

The chamfering grindstone 63 is, for example, an annular washer-shaped grindstone with a circular opening formed in the center, and is formed by fixing diamond abrasive grains or the like with a suitable resin bond. The chamfering grindstone 63 is fixed to the first spindle 61 while being sandwiched from above and below by a support flange 631 and a fixed flange 632. A recess 63a is formed on the entire circumference of the outer surface of the chamfered grindstone 63. The recess 63a has an approximately arcuate (approximately U-shaped) cross section; more precisely, as shown in an enlarged view in FIG. It is preferable to have one. For example, the maximum width of the recess 63a is set to 300 μm.
Note that the chamfering grindstone 63 may be of a hub type that includes a circular base metal (hub) and a cutting blade formed on the outer peripheral side of the base metal.

The truing means 7 includes, for example, at least a disk-shaped truing grindstone 70 with a sharp outer peripheral tip, and a second spindle 72 extending in the Z-axis direction in parallel to the first spindle 61.
For example, the second spindle 72 is rotatably housed in the housing 10 from its upper end to its intermediate portion, and its lower end protrudes from the bottom plate of the housing 10 to the outside. Further, a truing motor 73 is connected to the lower end of the second spindle 72, and the second spindle 72 is rotationally driven by the truing motor 73.

The truing whetstone 70 is, for example, an annular washer-shaped whetstone with a circular opening 700 (see FIG. 2) formed in the center, and is formed by fixing diamond abrasive grains or the like with a suitable metal bond. FIG. 2 shows an example of the dimensions of the truing grindstone 70. For example, the truing grindstone 70 has a V-shaped cross-sectional shape at the tip, an inclination angle of 20 degrees, a diameter of 58 mm, and a diameter of the opening 700 of 40 mm. Further, its maximum thickness is set to 1 mm, and the thickness at the tip is set to 150 μm, which is thinner than the chamfering grindstone 63, which is thinner than the conventional truing grindstone. Note that the thickness of the tip of the truing grindstone 70 is preferably 100 μm to 200 μm.

As shown in FIGS. 1(A) and 1(B), the truing grindstone 70 is attached to the support flange 7.
11 and a fixed flange 712 from above and below, and is fixed to the second spindle 72. The truing grindstone 70 is not limited to the above example, and may be an annular washer-type grindstone having a uniform thickness (for example, thickness 150 μm).

As shown in FIGS. 1(A) and 1(B), a support member 74 having a plate-like outer shape and having a bearing 740 inside is attached to the mounting shelf 181. is rotatably supported.

A taper shim 20 made of a rigid material and having a predetermined inclined surface is disposed between the upper surface of the shelf 181 and the lower surface of the support member 74 so as to be sandwiched from above and below. For example, the angle of inclination of the inclined surface of the taper shim is 2 degrees. Then, the second spindle 72 is tilted at a predetermined angle (for example, 2 degrees) with respect to the first spindle 61 by the taper shim 20 in the −Y direction, which is perpendicular to the X-axis direction and the Z-axis direction. It has become. The taper shim 20 is removable from the shelf 181, and can be replaced with another taper shim having an inclined surface with an inclination angle of 1 degree, for example.

The operation of the chamfering device 1 when chamfering the edge Wd of the wafer W by the chamfering device 1 shown in FIGS. 1(A) and 1(B) will be described below.
First, a desired recess 63a is formed on the outer surface of the chamfering grindstone 63. That is, as the second spindle 72, which is tilted at a predetermined angle (for example, 2 degrees) in the −Y direction with respect to the first spindle 61, is rotationally driven by the truing motor 73, the truing grindstone 70 is rotated. It also rotates.

Further, as the first spindle 61 is rotationally driven by the motor 64, the chamfering grindstone 63 also rotates around the axis in the Z-axis direction. Further, the chamfering means 6 is sent in the -X direction by the X-axis moving means 15 at a predetermined feed rate, and the outer surface of the rotating chamfering grindstone 63 comes into contact with the tip of the rotating truing grindstone 70, so that the entire outer surface is A circumferential recess 63a is formed.

After forming the desired recess 63a on the outer surface of the chamfering whetstone 63, the chamfering means 6 is sent in the +X direction at a predetermined feed rate by the X-axis moving means 15, and is separated from the truing whetstone 70, and the rotating chamfering whetstone A recess 63a formed on the outer surface of the wafer W comes into contact with the edge Wd of the wafer W, and chamfering is performed. During the chamfering process, in order to prevent the wafer W from shifting on the holding means 30, the piston rod 341 of the wafer fixing means 34 descends toward the wafer W held by suction on the holding surface 30a of the holding means 30. The wafer W is pressed against the holding surface 30a by the piston rod 341. Furthermore, since the wafer W rotates as the holding means 30 that holds the wafer W rotates around the axis in the Z-axis direction, the shape of the recess 63a of the chamfering grindstone 63 is transferred to the entire circumference of the edge Wd of the wafer W. Chamfering is performed so that the
After the edge Wd of the wafer W is chamfered for a predetermined period of time, the chamfering means 6 is sent in the -X direction by the X-axis moving means 15 and separated from the edge Wd of the wafer W, thereby chamfering the wafer W. ends.

The chamfered wafer W is carried out from the holding surface 30a of the holding means 30, and a new wafer W is placed on the holding surface 30a and held by suction. Then, the chamfering means 6 is sent in the +X direction at a predetermined feed speed by the X-axis moving means 15, and the edge Wd of the wafer W is similarly chamfered.
As the edge Wd of the wafer W is chamfered as described above on one or more wafers W, the chamfering grindstone 63 is worn and the shape of the recess 63a changes. Therefore, after chamfering is performed on one or more wafers W, at an appropriate timing, the chamfering means 6 is sent in the -X direction at a predetermined feed rate by the X-axis moving means 15, and the rotating chamfering When the outer surface of the grindstone 63 comes into contact with the tip of the rotating truing grindstone 70, the recess 63a around the entire outer surface is shaped.

As the recess 63a of the chamfering whetstone 63 is shaped and formed by the truing whetstone 70 as described above, the truing whetstone 70 also wears out. Here, in the wafer chamfer processing apparatus 1 according to the present invention, the above-mentioned angle (for example, 2 degrees) of the worn truing grindstone 70 can be changed by replacing the taper shim 20 with a taper shim having an inclined surface with a different inclination angle. , it becomes possible to form a desired approximately U-shaped recess 63a on the outer surface of the chamfered grindstone 63. Therefore, there is no need for time-consuming dressing or replacement of the truing grindstone 70, so there is no need to stop the chamfering device 1 for the above-mentioned work. Therefore, the productivity of chamfering the wafer W is not reduced.

(Embodiment 2)
The chamfering device 1A shown in FIGS. 3A and 3B is obtained by modifying some of the components of the chamfering device 1 shown in FIGS. 1A and 1B. Below, the differences between the chamfering device 1A and the chamfering device 1 will be explained in detail.

In the chamfering device 1A, a deformable member 75 such as a rubber plate or a spring is disposed between the lower surface of the support member 74 that supports the second spindle 72 of the truing means 7 and the upper surface of the mounting shelf 181. has been done.

The wafer chamfer processing apparatus 1A according to the present invention includes an angle changing means 21 shown in FIG. 3(B) that changes the inclination angle of the second spindle 72 with respect to the first spindle 61. The angle changing means 21 is sandwiched between the upper surface of the mounting shelf 181 and the lower surface of the support member 74, and faces the deformable member 75 in the Y-axis direction.

The angle changing means 21 includes, for example, a lower taper shim 211 fixed to the upper surface of the mounting shelf 181 and having a predetermined inclined surface (upper surface). A guide groove 211a extending in the Y-axis direction is formed in the inclined surface (upper surface) of the lower taper shim 211. A horizontal ball screw 212 extends in the Y-axis direction within the guide groove 211a, and a columnar movable member 213 is screwed into the horizontal ball screw 212 by a nut provided therein. A motor 214 is connected to the rear end side (+Y direction side) of the horizontal ball screw 212, and the movable member 213 moves along the guide groove 211a in accordance with the rotation direction of the horizontal ball screw 212 that is rotationally driven by the motor 214. Moves back and forth in the axial direction.

An upper taper shim 215 having a predetermined slope (lower surface) is disposed above the lower taper shim 211, and the slope of the upper taper shim 215 faces the slope of the lower taper shim 211. A fitting hole 215a is formed in the inclined surface of the upper taper shim 215, and the movable member 213 is fitted into the fitting hole 215a. Therefore, as the movable member 213 reciprocates in the Y-axis direction, the upper taper shim 215 moves in the Y-axis direction so that its sloped surface follows the sloped surface of the lower taper shim 211, and the supporting member The height position of the upper surface in contact with 74 also changes.
As the height position of the upper taper shim 215 changes, the tilt of the support member 74 changes while the deformation member 75 deforms, and the tilt of the second spindle 72 supported by the support member 74 changes from the Z-axis direction. The angle in the Y-axis direction also changes.

As shown in FIG. 3(B), for example, a recess shape measurement sensor 16 for measuring the shape of the recess 63a of the chamfering grindstone 63 is disposed within the housing 10. The recess shape measurement sensor 16 measures, for example, the maximum width of the cross-sectional shape (approximately U-shape) of the recess 63a of the chamfering grindstone 63 by emitting measurement light.

As shown in FIG. 3(B), the chamfering device 1A includes a control means 9 that controls each component of the device. The control means 9 including a CPU or the like is electrically connected to at least the motor 152 of the X-axis moving means 15, the motor 172 of the Z-axis moving means 17, the dent shape measuring sensor 16, and the motor 214 of the angle changing means 21. There is.

The control means 9 includes a storage medium such as a memory, and the storage medium functions as a convex shape memory section 91 that stores the convex shape of the cross section of the edge Wd of the wafer W that has been chamfered as desired.

The operation of the chamfering device 1A when chamfering the edge Wd of the wafer W by the chamfering device 1A shown in FIGS. 3A and 3B will be described below.
First, a desired recess 63a is formed on the outer surface of the chamfering grindstone 63. That is, as the second spindle 72, which is tilted at a predetermined angle (for example, 1 degree) in the −Y direction by the angle changing means 21 with respect to the first spindle 61, is rotationally driven by the truing motor 73, The truing grindstone 70 also rotates.

Further, as the first spindle 61 is rotationally driven by the motor 64, the chamfering grindstone 63 also rotates around the axis in the Z-axis direction. Further, the chamfering means 6 is sent in the -X direction by the X-axis moving means 15 at a predetermined feed rate, and the outer surface of the rotating chamfering grindstone 63 comes into contact with the tip of the rotating truing grindstone 70, so that the entire outer surface is A circumferential recess 63a is formed.

Here, as shown in FIG. 4, by raising and lowering the chamfering means 6 at a predetermined lifting speed by the Z-axis moving means 17 (see FIG. 3(B)), the chamfering means 6 is raised and lowered relative to the chamfering means 6. The arc-shaped portion 63c of the recess 63a is formed by the truing grindstone 70.

After the arc-shaped portion 63c is formed on the chamfering grindstone 63, the angle changing means 21 shown in FIG. For example, 2 degrees). That is, the tilt angle increases from 1 degree to 2 degrees.
Then, as shown in FIG. 5, a linearly tapered portion 63b of the recess 63a is formed by the rotating truing grindstone 70.

After forming a desired recess 63a including a linear taper portion 63b and an arcuate portion 63c shown in FIG. 5 on the outer surface of the chamfering grindstone 63, chamfering is performed by the X-axis moving means 15 shown in FIGS. 3(A) and 3(B). The processing means 6 is sent in the +X direction at a predetermined feed speed and is separated from the truing grindstone 70, and the recess 63a formed on the outer surface of the rotating chamfering grindstone 63 comes into contact with the edge Wd of the wafer W to perform the chamfering process. administered. During the chamfering process, the wafer W is pressed against the holding surface 30a by the piston rod 341 of the wafer fixing means 34. Furthermore, since the wafer W rotates as the holding means 30 that holds the wafer W rotates around the axis in the Z-axis direction, the shape of the recess 63a of the chamfering grindstone 63 is transferred to the entire circumference of the edge Wd of the wafer W. Chamfering is performed so that the Note that by forming the recess 63a with the linear taper portion 63b and the arc-shaped portion 63c, the edge Wd of the wafer W can be first shaved with the linear taper portion 63b and then shaved to match the arc-shaped portion 63c. can. Therefore, the edge Wd is not sharply scraped, and cracks and the like on the edge Wd are prevented from occurring.
After the edge Wd of the wafer W is chamfered for a predetermined period of time, the chamfering means 6 is sent in the -X direction by the X-axis moving means 15 and separated from the edge Wd of the wafer W, thereby chamfering the wafer W. ends.

The chamfered wafer W is carried out from the holding surface 30a of the holding means 30, and a new wafer W is placed on the holding surface 30a and held by suction. Then, the chamfering means 6 is sent in the +X direction at a predetermined feed speed by the X-axis moving means 15, and the edge Wd of the wafer W is similarly chamfered.
Here, for example, an appropriate convex shape of the cross section of the edge Wd of the wafer W which has been chamfered to a desired degree and carried out from the holding means 30 is measured by an operator or by an imaging means (not shown) provided in the chamfering apparatus 1A. . Then, information about the convex shape of the cross section of the edge Wd of the wafer W is input to the convex shape memory section 91 of the control means 9, and the convex shape memory section 91 stores the convex shape of the cross section of the edge Wd of the wafer W. remember.

By chamfering the edge Wd of the wafer W as described above on one or more wafers W, the chamfering grindstone 63 shown in FIGS. The shape of changes. Further, the truing grindstone 70 is also worn out by repeatedly shaping the recess 63a. Therefore, after chamfering is performed on one or more wafers W, the chamfering means 6 is sent at a predetermined feed speed in the -X direction by the X-axis moving means 15 at an appropriate timing, and as shown in FIG. The shape of the recess 63a of the chamfering grindstone 63 is measured by the recess shape measuring sensor 16 shown in B), and measurement information is transmitted from the recess shape measuring sensor 16 to the control means 9.

The chamfering means 6 is further sent in the -X direction at a predetermined feed rate by the X-axis moving means 15, and the outer surface of the rotating chamfering grindstone 63 comes into contact with the tip of the rotating truing grindstone 70, thereby cutting the entire circumference of the outer surface. The recess 63a is shaped. Here, the shape of the recess 63a measured by the recess shape measurement sensor 16 is combined with the appropriate recess shape of the cross section of the edge Wd of the wafer W stored by the recess shape memory unit 91 shown in FIG. 3(B). Thus, when forming the recess 63a, the angle changing means 21, the X-axis moving means 15, and the Z-axis moving means 17 are controlled by the control means 9 that receives measurement information from the recess shape measurement sensor 16.

For example, if the motor 152 of the X-axis moving means 15, the motor 172 of the Z-axis moving means 17, and the motor 214 of the angle changing means 21 are pulse motors operated by drive pulses supplied from a pulse oscillator (not shown), By counting the number of drive pulses supplied to the motor 152, motor 172, or motor 214, the control means 9 determines the position of the chamfering means 6 moved by the X-axis moving means 15 and the position of the chamfering means 6 moved by the Z-axis moving means 17. By grasping the height position of the chamfering means 6 to be moved and the inclination angle of the second spindle 72 with respect to the first spindle 61 which is changed by the angle changing means 21, for example, the dent 63a is formed by the worn truing grindstone 70. The positions of each component are controlled so that the arc-shaped portion 63c and the linearly tapered portion 63b are formed.

Note that the motor 152 of the X-axis moving means 15, the motor 172 of the Z-axis moving means 17, and the motor 214 of the angle changing means 21 may be servo motors, and a rotary encoder may be connected to the servo motors. The rotary encoder is connected to a control means 9 which also functions as a servo amplifier, and after an operation signal is supplied from the control means 9 to the servo motor, the encoder signal (rotation speed of the servo motor) is transmitted to the control means 9. Output for. The control means 9 controls the position of the chamfering means 6 moved by the X-axis moving means 15, the height position of the chamfering means 6 moved by the Z-axis moving means 17, and the angle changing means 21 according to the received encoder signal. By grasping the inclination angle of the second spindle 72 with respect to the first spindle 61 to be changed, for example, each component is adjusted so that an arc-shaped portion 63c and a linear taper portion 63b are formed in the recess 63a by the truing grindstone 70. Position control etc. are performed.

While being controlled by the control means 9, the outer surface of the rotating chamfering grindstone 63 comes into contact with the tip of the rotating truing grindstone 70, thereby shaping the recess 63a around the entire outer surface.
As the recess 63a of the chamfering whetstone 63 is shaped and formed by the truing whetstone 70 as described above, the truing whetstone 70 also wears out. Here, in the wafer chamfer processing apparatus 1A according to the present invention, by changing the above-mentioned angle of the worn truing grindstone 70 using the angle changing means 21, a desired approximately U-shaped recess is formed on the outer surface of the chamfering grindstone 63. 63a can be formed. Therefore, there is no need for time-consuming dressing or replacement of the truing grindstone 70, so there is no need to stop the chamfering device 1A for the above-mentioned work. Therefore, the productivity of chamfering the wafer W is not reduced.

The wafer chamfer processing apparatus 1A according to the present invention includes an angle changing means 21 that changes the inclination angle of the second spindle 72 with respect to the first spindle 61. It becomes easier to tilt 72 at a predetermined angle toward the Y-axis direction that is orthogonal to the X-axis direction and the Z-axis direction.

The wafer chamfer processing apparatus 1A according to the present invention includes a recess shape measuring sensor 16 that measures the shape of the recess 63a of the chamfering grindstone 63, and a recess shape measuring sensor 16 that memorizes the recess shape of the cross section of the edge Wd of the chamfered wafer W. The shape memory section 91, the Z-axis moving means 17 that relatively moves the chamfering means 6 and the truing means 7 in the Z-axis direction, and the convex shape of the wafer W stored by the convex shape memory section 91, A control means 9 that controls the angle changing means 21, the X-axis moving means 15, and the Z-axis moving means 17 when forming the dent 63a so that the shapes of the dents 63a of the chamfering grindstone 63 measured by the dent shape measurement sensor 16 are combined. , it becomes possible to always make the shape of the recess 63a a desired shape even when the truing grindstone 70 is worn out.

It goes without saying that the wafer chamfer processing apparatus according to the present invention is not limited to the first and second embodiments described above, and may be implemented in various different forms within the scope of the technical idea. Furthermore, the external shape and size of each component of the wafer chamfering apparatuses 1 and 1A illustrated in the attached drawings are not limited to these, and may be changed as appropriate within the scope of achieving the effects of the present invention. be.

For example, a diameter measuring means (such as an optical sensor) for measuring the diameter of the truing grindstone 70 is provided in the casing 10 of the wafer chamfering apparatus 1A shown in FIGS. 3A and 3B. Further, the control means 9 includes calculation means for calculating an appropriate angle of the angle changing means 21 shown in FIG. 3(B) from the diameter measured by the diameter measuring means. The angle of inclination of the second spindle 72 with respect to the first spindle 61 may be changed by the angle changing means 21 based on the angle calculated by the calculating means.

W: Wafer Wd: Wafer edge 1: Chamfering device 10: Housing 15: X-axis moving means 159: Base 150: Horizontal ball screw 151: Pair of guide rails 152: Motor 153: Movable plate 17: Z-axis moving means 179 : Pair of support plates 170: Vertical ball screw 171: Guide rail 172: Motor 173: Movable member 180: Bracket 181: Mounting shelf 30: Holding means 300: Suction path 30a: Holding surface 33: Rotary joint 39: Suction source 35: motor
34: Wafer fixing means 341: Piston rod 6: Chamfering means 61: First spindle 63: Chamfering grindstone 62: Housing 64: Motor 63: Chamfering grindstone 63a: Recess of chamfering grindstone
7: Truing means 70: Truing grindstone 72: Second spindle 73: Truing motor 74: Support means 20: Taper shim 1A: Chamfering device 74: Support means 75: Deformation member 21: Angle changing means 211: Lower taper shim 211a: Guide groove 213: Movable member 214: Motor 215: Upper taper shim 16: Concave shape measurement sensor 9: Control means 91: Convex shape memory section

Claims (2)

A holding means that holds a wafer and has a holding surface having a smaller diameter than the wafer diameter and is rotatable about a rotation axis extending in the Z-axis direction perpendicular to the holding surface , and an edge of the wafer held by the holding means. A wafer chamfering device comprising: a chamfering means for bringing a recess on an outer surface of a rotatable chamfering grindstone into contact and chamfering the edge;
A truing means for forming a recess on the outer surface of the chamfering grindstone, and an X-axis moving means for relatively moving the chamfering means and the truing means in an X-axis direction parallel to the holding surface,
The chamfering means includes a disc-shaped chamfering whetstone that is thicker than the thickness of the wafer, and a first part that has the chamfering whetstone attached to its tip and rotates the chamfering whetstone about an axis parallel to the rotation axis of the holding means. a spindle;
The truing means includes a disc-shaped truing grindstone that is thinner than the chamfered grindstone or has a pointed outer peripheral tip, and a second spindle to which the truing grindstone is fixed,
comprising angle changing means for changing the inclination angle of the second spindle with respect to the first spindle;
After the angle changing means changes the inclination angle of the second spindle relative to the first spindle in the Y-axis direction perpendicular to the X-axis direction and the Z-axis direction, the X-axis moving means A wafer chamfering device that moves the chamfering grindstone and the truing grindstone in a direction in which they approach each other relatively, and forms the recess on the outer surface of the chamfering grindstone. a concavity shape measuring sensor for measuring the shape of the concavity of the chamfering grindstone; a convexity shape memory section for memorizing the convexity shape of the cross section of the edge of the chamfered wafer; and the chamfering means in the Z-axis direction. Z-axis moving means for moving the truing means relatively;
When forming the dent, the angle changing means, the X-axis moving means, and the Z-axis are arranged so that the shape of the dent measured by the dent shape measurement sensor is combined with the dent shape stored in the dent shape memory section. The wafer chamfer processing apparatus according to claim 1, further comprising a control means for controlling the moving means.

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