JP2009202323A - Method for machining holding surface of planar object - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a cutting groove of a uniform depth in a workpiece held by a holding surface of a holding means for holding a planar object, also when the holding surface is not in parallel with a machining feed direction, in a cutting device for cutting the planar object held by the holding means by a cutting blade. <P>SOLUTION: In this cutting device, a cutting means 3 having the cutting blade supported by a blade supporting part and the holding means 2 for holding the planar object relatively move in the machining feed direction to form the cutting groove of a prescribed depth in the planar object held by the holding surface 23 of the holding means 2. Before forming the cutting groove, a plane grinding tool 8 in place of the cutting blade is mounted on the blade supporting part 31, the holding means 2 and the cutting means 3 are relatively machining fed, a grinding surface 80 of the plane grinding tool 8 located at a prescribed height to rotate is brought into contact with the holding surface 23 to grind the holding surface 23, and the machining feed direction and the holding surface 23 are made parallel with each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method of processing a holding surface of a holding unit that holds a workpiece in a cutting apparatus.

  A cutting device used for wafer dicing or the like includes a holding unit having a holding surface for holding a workpiece and a cutting unit having a cutting blade. Then, the holding means holding the workpiece on the holding surface and the cutting means are relatively processed and fed, and the holding means and the cutting means are relatively cut and fed so that the cutting blade cuts into the workpiece. Cutting is performed. And when cutting multiple places, like street cutting during wafer dicing, the holding means and the cutting means are relatively indexed and then the cutting blade cuts into the workpiece, and the cutting is performed sequentially. Done.

  In addition, for example, when a groove having a predetermined depth is formed on the surface of a plate-like object without being completely cut, such as when a groove is formed on the surface of a ferrite substrate and used for a sensor reading portion, Holding means while holding the workpiece on the holding surface, aligning the tip of the cutting blade at a predetermined height, and contacting the cutting blade rotating at high speed with the surface of the workpiece A cutting groove having a depth corresponding to the cutting depth of the cutting blade is formed by relatively feeding the cutting means and the cutting means (see, for example, Patent Document 1).

JP 2007-331049 A

  However, due to the assembled state of the holding means in the cutting apparatus, the holding surface of the holding means is not parallel to the processing feed direction that is the moving direction, and a height difference of about several μm occurs. There may be. In this case, if the cutting blade is cut into the surface of the plate-like object to form a cutting groove having a predetermined depth, the cutting depth of the cutting blade varies depending on the position in the machining feed direction. For example, when it is desired to form a groove having a depth of 20 μm, the depth of the groove varies between 20 and 25 μm.

  Therefore, the problem to be solved by the present invention is that in the cutting apparatus, even when the holding surface of the holding means for holding the plate-like object is not parallel to the processing feed direction of the holding means, the workpiece held on the holding surface It is to be able to form a cutting groove with a uniform depth in an object.

  The present invention includes a holding means having a holding surface for holding a plate-like object, a cutting blade having a cutting blade for cutting the plate-like object held by the holding means, and a blade support part for detachably supporting the cutting blade; X-axis feed means for moving the holding means and cutting means relative to each other in the X-axis direction; Y-axis feed means for relatively moving the holding means and cutting means in the Y-axis direction; The present invention relates to a method for processing a holding surface of a plate-like object in a cutting apparatus provided with at least a Z-axis feed means for cutting and feeding by relatively moving the means and the cutting means in the Z-axis direction. The surface grinding wheel mounting step for mounting the surface and the Z-axis feed unit relatively cuts and feeds the holding unit and the grinding unit in the Z-axis direction so that the grinding surface of the surface grinding wheel contacts the holding surface of the holding unit. A surface grinding wheel positioning step for aligning the surface grinding wheel and a holding surface of the holding means on the grinding surface of the surface grinding wheel by relatively feeding the holding means and the cutting means in the X-axis direction by the X-axis feeding means. A holding surface grinding step for grinding the workpiece and an index feeding step for relatively indexing and feeding the holding means and the cutting means in the Y-axis direction within a range not exceeding the width of the grinding surface of the surface grinding wheel by the Y-axis feeding means. The holding surface grinding step and the index feeding step are repeatedly performed to grind the entire holding surface of the holding means.

  The present invention attaches a surface grinding wheel to the blade support portion of the cutting means, contacts the holding surface of the holding means with the surface grinding wheel rotating while processing feed, and grinds the holding surface. The X-axis direction and the holding surface are parallel to each other. Therefore, if the cutting groove is formed on the plate-like object held by the holding means while the cutting blade is attached to the blade support portion and then the processing feed is performed, the bottom surface of the cutting groove and the processing feed direction are determined. It becomes parallel, and the depth of the cutting groove is uniform in the machining feed direction.

  A cutting apparatus 1 shown in FIG. 1 includes a holding unit 2 that holds a plate-like object to be cut, and a cutting unit 3 that cuts the plate-like object held by the holding unit 2.

  The holding means 2 includes a suction portion 20 that is a portion on which a plate-like object is placed and sucked, and a frame body 21 that surrounds and supports the periphery. The adsorbing portion 20 is formed of a porous member formed by compressing and baking silicon particles having a particle size of approximately 50 μm at approximately 1200 ° C., and the frame body 21 is formed of, for example, polycrystalline silicon. Further, when the plate-like object W is supported integrally with the frame F via the holding tape T as shown in the figure, a fixing portion 22 for fixing the frame F is disposed outside the frame body 21. A surface formed by connecting the surface of the suction portion 20 and the surface of the frame body 21 is a holding surface 23 that holds the plate-like object W.

  The holding means 2 is configured to be processed and fed in the X-axis direction by the X-axis feeding means 5. That is, the X-axis direction is the moving direction of the holding means 2. The X-axis feed means 5 includes a ball screw 50 having an axis in the X-axis direction, a pair of guide rails 51 disposed in parallel to the ball screw 50, a motor 52 connected to one end of the ball screw 50, and an internal nut Is constituted by a moving base 53 whose lower part is slidably contacted with the guide rail 51 and a rotation driving unit 54 which is fixed to the moving base 53 and rotates the holding means 2. Accordingly, as the ball screw 50 rotates, the moving base 53 and the rotation driving unit 54 are guided by the guide rail 51 and moved in the X-axis direction, and the holding means 2 is also moved in the same direction.

  The cutting means 3 can be moved in the Z-axis direction by the Z-axis feeding means 6 and can be moved in the Y-axis direction by the Y-axis feeding means 7. The Z-axis feed means 6 includes a ball screw 60 arranged in the Z-axis direction, a pair of guide rails 61 arranged in parallel to the ball screw 60, a pulse motor 62 connected to one end of the ball screw 60, and cutting means 3 and a support part 63 whose inner nut is screwed into the ball screw 60 and whose side part is in sliding contact with the guide rail 61. The ball screw 60 is driven by the pulse motor 62 to rotate. The support portion 63 is guided by the guide rail 61 and is moved up and down in the Z-axis direction so that the cutting means 3 is also moved up and down. The Z-axis direction is a vertical direction orthogonal to the X-axis direction and is the cutting direction of the cutting blade 30.

  The Y-axis feed means 7 includes a ball screw 70 arranged in the Y-axis direction, a pair of guide rails 71 arranged in parallel to the ball screw 70, a pulse motor 72 connected to one end of the ball screw 70, The Z-axis feed means 6 is provided, and the inner nut is screwed into the ball screw 70 and the lower part is configured to be in sliding contact with the guide rail 71. The ball screw 70 is driven by the pulse motor 72 to rotate. Accordingly, the moving base 73 is guided by the guide rail 71 and moved in the Y-axis direction, and the cutting means 3 is also moved in the Y-axis direction. The Y-axis direction is a direction orthogonal to the X-axis direction and the Z-axis direction, and is an indexing direction of the cutting blade 30.

  As shown in FIG. 2, the cutting means 3 includes a cutting blade 30 that performs cutting while contacting a plate-like object, and a blade support portion 31 that detachably supports the cutting blade 30. The blade support portion 31 is attached to the spindle 32 having a center in the Y-axis direction on which the cutting blade 30 is mounted, a housing 33 that rotatably supports the spindle 32, and a tip portion of the housing 33. A fixed cover 34, a detachable cover 35 that can be attached to and detached from the fixed cover 34 with a bolt 35a, and a blade inspection unit 36 that can be attached to and detached from the fixed cover 34 with a bolt 36a and inspects the state of wear of the cutting blade 30, etc. And. The fixed cover 34 and the detachable cover 35 are provided with cutting water inlets 340 and 350 supplied to the contact portion between the cutting blade 30 and the plate-like object, and cutting for discharging the cutting water flowing from the inlets 340 and 350. Water nozzles 341 and 351 are provided, respectively.

  As shown in FIG. 1, an alignment unit 4 is fixed to the side portion of the housing 33 to detect a position where the wafer is to be cut and align the position with the cutting blade 30. The alignment unit 4 includes an imaging unit 40 that images the surface of the plate-like object held by the holding unit 2.

  As shown in FIG. 3, the cutting blade 30 includes a base 30b having a through hole 30a formed in the center thereof, and a cutting blade 30c fixed to the peripheral edge of the base 30b. The outer periphery of the cutting blade 30c is formed in a shape corresponding to the shape of the cutting groove to be formed.

  A flange mounting portion 320 having a tapered surface and a male screw 321 are formed at the tip portion of the spindle 32.

  The fixed flange 37 is mounted on the flange mounting portion 320. The fixed flange 37 is formed at a contact portion 37a for contacting the base 30b of the cutting blade 30, a fitting portion 37b for fitting the through hole 30a of the cutting blade 30, and a tip portion of the fitting portion 37b. The formed male screw 37c and a through hole 37d for insertion into the flange mounting portion 320 are formed. Although not shown, the inner peripheral surface of the through hole 37d is formed in a tapered surface corresponding to the tapered surface of the flange mounting portion 320.

  When the cutting blade 30 is mounted on the tip of the spindle 32, the fixing flange 37 is fixed to the spindle 32 by mounting the fixing flange 37 on the flange mounting portion 320 of the spindle 32 and screwing the nut 38 to the male screw 37 c. In this state, the through hole 30a of the cutting blade 30 is inserted and fitted into the fitting portion 37b of the fixed flange 37, and the base 30b of the cutting blade 30 is brought into contact with the contact portion 37a. Then, when the nut 39 is screwed onto the male screw 37 c, the cutting blade 30 is fixed to the spindle 32 via the fixing flange 37.

  For example, in the case where a cutting groove having a predetermined depth is formed on the surface of the plate-like object W shown in FIG. 1, the plate-like object W held by the holding means 2 is rotated at a high speed while being fed in the X-axis direction. In order to cut the cutting blade 30 into the plate-like object W, the X-axis direction (processing feed direction) that is the moving direction of the holding means 2 and the holding surface 20 of the holding means 2 are not parallel to each other. The depth is not uniform.

  Therefore, before forming the cutting groove, the detachable cover 35 and the blade inspection part 36 are removed from the fixed cover 34 shown in FIG. 2, and then the nut 39 is removed and the cutting blade 30 is fixed as shown in FIG. Remove from the flange 37. For convenience of explanation, the illustration of the fixed cover 34 is omitted in FIG. 4, but this is left attached.

  Next, as shown in FIG. 5, the surface grinding wheel 8 is mounted on the spindle 32 constituting the blade support 31 via the fixed flange 37, and the nut 39 is screwed onto the male screw 37c. Although not shown, the detachable cover 35 is attached to the fixed cover 34 with bolts 35a. The surface grinding wheel 8 is formed by, for example, diamond abrasive grains hardened by vitrified bond and formed in a ring shape, and the outer peripheral surface thereof is a grinding surface 80, and the grinding surface 80 has a predetermined width (surface grinding wheel). Mounting process).

  When the surface grinding wheel 8 is thus attached to the spindle 32, the cutting means 3 is moved in the Y-axis direction by the Y-axis feed means 7 shown in FIG. 1, and the Y-axis direction of the surface grinding wheel 8 as shown in FIG. Is positioned above the end of the holding surface 23 in the Y-axis direction. This alignment is performed by the alignment 4 shown in FIG. Next, while maintaining the position of the surface grinding wheel 8 in the Y-axis direction, the cutting means 3 is lowered (cut feed) by the Z-axis feeding means 6 shown in FIG. 1, and as shown in FIG. 8 is a position where the lower end 80a of the grinding surface 80 is slightly lower than the holding surface 23 (for example, a position slightly lower than the maximum height difference of the holding surface 23 by 10 μm from the highest part of the holding surface 23), that is, the grinding surface 80 holds. Positioning is performed at a position in contact with the surface 23 (surface grinding wheel positioning step). This alignment control is performed based on coordinate information that the Z-axis feed unit 6 has in advance.

  The spindle 32 is rotated at a high speed while the surface grinding wheel 8 maintains the positions in the Y-axis direction and the Z-axis direction, and the holding means 2 is moved in the X-axis direction by driving the X-axis feeding means 5 shown in FIG. 8, the holding means 2 and the surface grinding wheel 8 are brought closer to each other as shown in FIG. 8, and the grinding surface 80 of the surface grinding wheel 8 rotating at a high speed is held as shown in FIG. 23. When the grinding surface 80 is further in contact with the holding surface 23 and further processed by the X-axis feed means 5, the portion of the holding surface 23 that is in contact with the grinding surface 80 becomes a line having the width of the grinding surface 80. It is ground (holding surface grinding process).

  Next, in a state where the surface grinding wheel 8 is separated from the holding surface 23, the Y-axis feed unit 6 shown in FIG. 1 moves the cutting unit 3 to the Y axis within a range not exceeding the width of the grinding surface 80 of the surface grinding wheel 8. Indexing feed is performed in the direction so that the position of the grinding surface 80 in the Y-axis direction is aligned with the unground position of the holding surface 23 (index feed process). In this state, the holding means 2 is moved in the X-axis direction by driving the X-axis feed means 5 (see FIG. 1), and the holding surface grinding process is performed. Then, in addition to the first ground portion, the adjacent portion is ground linearly.

  In this way, when the index feeding step and the holding surface grinding step are alternately repeated and grinding is performed sequentially as shown in FIG. 10, the entire surface of the holding surface 23 is ground. As shown in FIG. 11, even if the holding surface 23 before grinding is inclined with respect to the X-axis direction, the surface to be ground 23 a that is the holding surface after grinding is in the moving direction of the holding means 2. It becomes parallel to a certain X-axis direction.

  After the entire surface to be ground 23a is parallel to the X-axis direction, the surface grinding wheel 8 is removed from the fixed flange 37 shown in FIGS. 3 to 5, and the cutting groove forming cutting blade shown in FIG. 30 is attached to the fixing flange 37, and the nut 39 is screwed onto the male screw 37c.

  Referring to FIG. 1, next, for example, the cutting blade 30 is positioned immediately above the holding means 2, and the cutting means 3 is moved down by the control by the Z-axis feeding means 6. The position when the lower end of 30c contacts the holding surface 23a is grasped as the origin in the Z-axis direction.

  Next, the holding means 2 supports the plate-like object W in a state integrated with the frame F via the holding tape T as shown in FIG. After the position to be cut by the alignment means 4 is detected by the movement of the Y axis direction and the Z axis direction of 40 and the position of the cutting blade 30 in the Y axis direction is aligned, as shown in FIG. And the cutting blade 30 is cut into the position to form a cutting groove G having a predetermined depth. At this time, the height of the lower end of the cutting blade 30 in the Z-axis direction is precisely controlled by the cutting feed by the Z-axis feeding means. Since the ground surface 23a of the holding means 2 and the X-axis direction are parallel to each other with high precision, the depth of the cutting groove G is uniform.

  In the above example, the X-axis feeding means 5 drives the holding means 2 in the X-axis direction, the Y-axis feeding means 7 drives the cutting means 3 in the Y-axis direction, and the Z-axis feeding means 6 is the cutting means 3. Is driven in the Z-axis direction, but the X-axis feed means 5 drives the cutting means 3 in the X-axis direction, and the Y-axis feed means 7 drives the holding means 2 in the Y-axis direction. Also good. The Z-axis feed means 6 drives the holding means 2 in the Z-axis direction, and the cutting means 3 does not move in the Z-axis direction. In other words, the X-axis feed means 5 may be configured so that the holding means 2 and the cutting means 3 can be moved and moved relative to each other in the X-axis direction. The Z-axis feed unit 6 may be configured to be able to cut and feed by relatively moving the holding unit 2 and the cutting unit 3 in the Z-axis direction. .

It is a perspective view which shows an example of a cutting device. It is a disassembled perspective view which shows an example of a cutting means. It is a disassembled perspective view which shows the principal part of a cutting means. It is a perspective view which shows the state which removes a cutting blade from a cutting means. It is a perspective view which shows the state which mounts | wears with the surface grinding grindstone to a cutting means. It is a side view which shows roughly the state which aligned the surface grinding stone in the Y-axis direction. It is a front view which shows roughly the state which aligned the surface grinding stone in the Z-axis direction. It is a perspective view which shows the state just before grinding the holding surface of a holding means. It is a front view which shows the state which grinds a holding surface schematically. It is a side view which shows the state which grinds a holding surface schematically. It is explanatory drawing which shows the relationship between the X-axis and the holding surface after grinding. It is a front view which shows roughly the state which forms a cutting groove in a plate-shaped object after holding surface grinding.

Explanation of symbols

1: Cutting device 2: Holding means 20: Adsorption part 21: Frame body 22: Fixing part 23: Holding surface 23a: Surface to be ground 3: Cutting means 30: Cutting blade 30a: Through hole 30b: Base 30c: Cutting blade 31 : Blade support part 32: Spindle 320: Flange mounting part 321: Male screw 33: Housing 34: Fixed cover 35: Removable cover 36: Blade inspection part 37: Fixed flange 37 a: Abutting part 37 b: Fitting part 37 c: Male screw 37d: Through-hole 38, 39: Nut 4: Alignment means 40: Imaging part 5: X-axis feed means 50: Ball screw 51: Guide rail 52: Motor 53: Moving base 54: Rotation drive part 6: Z-axis feed means 60 : Ball screw 61: Guide rail 62: Pulse motor 63: Support part 7: Y-axis feeding means 70: Ball screw 71: Guide rail 72: Pal Motor 73: movable base 8: plan grinding wheel 80: grinding surface

Claims (1)

A holding means having a holding surface for holding a plate-like object; a cutting means having a cutting blade for cutting the plate-like object held by the holding means; and a blade support part for detachably supporting the cutting blade; An X-axis feeding means for moving the holding means and the cutting means relative to each other in the X-axis direction; a Y-axis feeding means for indexing and feeding the holding means and the cutting means relative to each other in the Y-axis direction; A method for processing a holding surface of a plate-like object in a cutting apparatus comprising at least a Z-axis feeding means for cutting and feeding the holding means and the cutting means relative to each other in the Z-axis direction,
A surface grinding wheel mounting step of mounting a surface grinding wheel on the blade support of the cutting means;
The holding means and the grinding means are relatively cut and fed in the Z-axis direction by the Z-axis feeding means so that the grinding surface of the surface grinding wheel comes into contact with the holding surface of the holding means. Surface grinding wheel positioning process to align,
A holding surface grinding step of grinding the holding surface of the holding means with the grinding surface of the surface grinding wheel by relatively feeding the holding means and the cutting means in the X-axis direction by the X-axis feeding means;
An indexing and feeding step in which the holding means and the cutting means are relatively indexed and fed in the Y-axis direction within a range not exceeding the width of the grinding surface of the surface grinding wheel by the Y-axis feeding means,
A processing method for a holding surface of a plate-like object, in which the holding surface grinding step and the index feeding step are repeatedly performed to grind the entire holding surface of the holding means.

Images