JP7560313B2 - Cutting Equipment - Google Patents

Description

The present invention relates to a cutting device.

A cutting device that uses a cutting blade to cut a wafer held on a chuck table fills the top surface of the wafer with water during cutting to prevent cutting debris generated by the wafer grinding process from adhering to the top surface of the wafer. As disclosed in Patent Document 1, the wafer is cut by moving the chuck table while water is spread over the entire top surface of the wafer.

However, the water flow on the top surface of the wafer is small or nonexistent, and the gap between the bottom surface of the spindle unit that rotates the cutting blade and the top surface of the wafer is filled with water, so that the top surface of the wafer and the bottom surface of the spindle unit are joined together via the water.
As a result, no flow occurs in the water above the wafer, and cutting debris remains in the water layer above the wafer and adheres to the wafer surface.
Furthermore, there are inventions in which a water tank is formed and the entire upper surface of the wafer is filled with water, as disclosed in Patent Documents 2 and 3. In this case as well, there is no flow of water on the upper surface of the wafer, and cutting debris adheres to the upper surface of the wafer.

JP 2005-222990 A JP 2001-135596 A JP 2017-094455 A

Therefore, the cutting device faces the challenge of forming a water layer with a water flow on the top surface of the wafer to prevent cutting debris from adhering.

The present invention is a cutting device comprising a chuck table which holds a wafer on a holding surface, a cutting blade which is disposed at the tip of a spindle and which cuts the wafer held on the holding surface, and a cutting feed means which cuts the wafer by feeding the chuck table in a cutting feed direction which is forward relative to the rotation direction of the cutting blade, and the cutting device comprises a water nozzle which extends parallel to the spindle and is disposed upstream of the spindle in the cutting feed direction, and which sprays water in a forward direction relative to the cutting feed direction of the chuck table which is fed for cutting during the cutting process of the wafer , to form a water layer on the upper surface of the wafer held on the holding surface, and an air nozzle which extends parallel to the spindle and the water nozzle and is disposed downstream of the water nozzle in the cutting feed direction, and which sprays water from the water nozzle to form the water layer, while flowing air in a forward direction relative to the cutting feed direction of the chuck table on the upper surface of the water layer, to form a water flow in the forward direction of the cutting feed direction.
In the above cutting device, it is desirable that the water nozzle and the air nozzle are disposed adjacent to the chuck table and moved together with the chuck table in the cutting feed direction.
The air nozzle may be one that sprays two fluids, that is, air mixed with water.

In the cutting device of the present invention, water is sprayed from the water nozzle and air is sprayed from the air nozzle during the wafer grinding process, creating a water flow on the top surface of the wafer, which washes away grinding debris generated during the wafer grinding process from the top surface of the wafer.

FIG. 2 is a perspective view illustrating an entire cutting device. FIG. 4 is a cross-sectional view of the cutting means and the holding means. FIG. 4 is a cross-sectional view of the cutting means and the holding means.

1 Configuration of the cutting device The cutting device 1 shown in Fig. 1 is a cutting device that cuts a wafer 140 using a first cutting means 31 and a second cutting means 32. With the wafer 140 positioned inside an annular frame 141, a tape 142 is attached to the lower surface of the frame 141 and the lower surface of the wafer 140, thereby forming a work unit 14 in which the wafer 140, the frame 141, and the tape 142 are integrated. A plurality of mutually orthogonal planned division lines 1402 are formed on an upper surface 1400 of the wafer 140, and devices 1401 are arranged in the areas defined by the planned division lines 1402. The configuration of the cutting device 1 will be described below.

The cutting device 1 has a base 10 that extends horizontally as shown in FIG. 1. The +X direction side and -Y direction side of the base 10 form a cassette stage 100, on which a cassette (not shown) that contains a work unit 14 is placed.

A gate-type column 11 is erected on the -X direction side of the base 10. A first Z-axis moving means 41 is disposed on the +X direction side and +Y direction side of the gate-type column 11, and supports the first cutting means 31 so that it can be raised and lowered.

The first Z-axis moving means 41 includes a ball screw 410 having a rotating shaft 415 in the Z-axis direction, a guide rail 411 arranged parallel to the ball screw 410, a Z-axis motor 412 that rotates the ball screw 410 around the rotating shaft 415, and a lift plate 413 whose side nut is screwed onto the ball screw 410 and slides against the guide rail 411. The lift plate 413 is connected to the spindle housing 311.

By rotating the ball screw 410 using the Z-axis motor 412, the lift plate 413 moves in the Z-axis direction while being guided by the guide rail 411, and the spindle housing 311 connected to the lift plate 413 also moves in the Z-axis direction.

The first cutting means 31 comprises a cutting blade 310, a spindle housing 311, and a first spindle 312 housed inside the spindle housing 311. The first spindle 312 extends in the Y-axis direction, and the cutting blade 310 is attached to the -Y-direction side of the first spindle 312. The first spindle 312 is connected to a motor or the like (not shown), and when the first spindle 312 is driven to rotate by the motor, the cutting blade 310 connected to the first spindle 312 rotates.

An imaging means 33 having a camera or the like is disposed adjacent to the cutting blade 310. The imaging means 33 can be used to capture an image of the planned division line 1402 formed on the wafer 140 held on the holding surface 200 of the chuck table 2.

A second Z-axis moving means 42 is provided on the +X and -Y sides of the gate-shaped column 11 to support the second cutting means 32 so that it can be raised and lowered.

The second Z-axis moving means 42 is configured in the same manner as the first Z-axis moving means 41. That is, the second Z-axis moving means 42 includes a ball screw 420 having a rotating shaft 425 in the Z-axis direction, a guide rail 421 arranged parallel to the ball screw 420, a Z-axis motor 422 that rotates the ball screw 420 around the rotating shaft 425, and a lift plate 423 whose side nut is screwed onto the ball screw 420 and slides against the guide rail 421. The lift plate 423 is connected to the spindle housing 321.

When the ball screw 420 is rotated using the Z-axis motor 422, the lift plate 423 moves in the Z-axis direction while being guided by the guide rail 421, and the spindle housing 321 connected to the lift plate 423 moves in the Z-axis direction accordingly.

The second cutting means 32 is configured in the same manner as the first cutting means 31. That is, the second cutting means 32 includes a cutting blade 320, a spindle housing 321, and a second spindle 322 housed inside the spindle housing 321. The second spindle 322 extends in the Y-axis direction, and the cutting blade 320 is rotatably attached to the +Y-direction side of the second spindle 322. The second spindle 322 is connected to a motor or the like (not shown), and when the second spindle 322 is driven to rotate by the motor, the cutting blade 320 attached to the second spindle 322 rotates.

The portal column 11 is provided with a first Y-axis moving means 51 for moving the first cutting means 31 in the Y-axis direction, and a second Y-axis moving means 52 for moving the second cutting means 32 in the Y-axis direction.

The first Y-axis moving means 51 includes a ball screw 510 having an axis in the Y-axis direction, a Y-axis motor (not shown) that rotates the ball screw 510, a guide rail 511 arranged parallel to the ball screw 510, and a slide plate 513 whose side nut is screwed onto the ball screw 510 and slides against the guide rail 511. The slide plate 513 supports the first Z-axis moving means 41.

When the ball screw 510 is rotated using the Y-axis motor, the slide plate 513 moves in the Y-axis direction while being guided by the guide rail 511, and accordingly, the first Z-axis moving means 41 supported by the slide plate 513 and the first cutting means 31 supported by the lift plate 413 of the first Z-axis moving means 41 move integrally in the Y-axis direction.

The second Y-axis moving means 52 is configured in the same manner as the first Y-axis moving means 51. That is, the second Y-axis moving means 52 includes a ball screw 520 having an axis 525 in the Y-axis direction, a Y-axis motor 522 that rotates the ball screw 520, a guide rail 521 arranged parallel to the ball screw 520, and a slide plate 523 whose side nut is screwed onto the ball screw 520 and slides against the guide rail 521.

When the ball screw 520 is rotated using the Y-axis motor 522, the slide plate 523 moves in the Y-axis direction while being guided by the guide rail 521, and accordingly the second Z-axis moving means 42 supported by the slide plate 523 and the second cutting means 32 supported by the lift plate 423 of the second Z-axis moving means 42 move integrally in the Y-axis direction. The guide rail 521 also serves as a guide for the slide plate 513 of the first Y-axis moving means 51 when it moves, and similarly, the guide rail 511 of the first Y-axis moving means 51 also serves as a guide for the slide plate 523 of the second Y-axis moving means 52 when it moves.

A chuck table 2 is disposed on the base 10. The chuck table 2 has a disk-shaped suction portion 20 and an annular frame body 21 that supports the suction portion 20. The upper surface of the suction portion 20 is a holding surface 200 on which the work unit 14 is held, and the upper surface 210 of the frame body 21 is formed flush with the holding surface 200.

Four clamps 23 are arranged adjacent to the chuck table 2 so as to surround the chuck table 2 on all four sides. The work unit 14 is placed on the holding surface 200 with the upper surface 1400 facing in the +Z direction so that the tape 142 contacts the holding surface 200, and the frame 141 is clamped on all four sides using the four clamps 23, thereby fixing the work unit 14 on the holding surface 200.

The chuck table 2 is connected to a suction source 29. By activating the suction source 29, the suction force generated is transmitted to the holding surface 200. For example, by placing the work unit 14 on the holding surface 200 and activating the suction source 29, the wafer 140 can be suction-held on the holding surface 200.

The chuck table 2 is also connected to a rotating means (not shown). The chuck table 2 can be rotated by using the rotating means.

The cutting device 1 is equipped with a cutting feed means 26 that moves the chuck table 2 horizontally in the X-axis direction. For example, when a wafer 140 is held on the holding surface 200 of the chuck table 2, the cutting feed means 26 is used to move the chuck table 2 horizontally in the X-axis direction, thereby making it possible to move the wafer 140 in the X-axis direction.

A cover 27 is disposed around the chuck table 2, and the cover 27 is connected to a bellows 28 so as to be expandable and contractible.
When the chuck table 2 moves in the X-axis direction, the cover 27 moves integrally with the chuck table 2 in the Y-axis direction, causing the bellows 28 to expand and contract.

The cutting device 1 is equipped with a water nozzle 60. The water nozzle 60 is disposed so as to extend parallel to the Y-axis direction, which is the extension direction of the first spindle 312 and the second spindle 322, and is disposed on the +X direction side, which is the upstream side of the cutting feed direction. As shown in FIG. 2, the water nozzle 60 is disposed in a horizontal position adjacent to the chuck table 2, and is fixed above the clamp 23, which is disposed on the +X direction side of the chuck table 2. The nozzle of the water nozzle 60 is oriented in a direction between the -X direction and the -Z direction.
The water nozzle 60 is connected to a water supply source 600 , and water can be sprayed toward the holding surface 200 of the chuck table 2 by supplying water from the water supply source 600 to the water nozzle 60 .

The cutting device 1 is equipped with an air nozzle 61. The air nozzle 61 is arranged to extend parallel to the first spindle 312, the second spindle 322, and the water nozzle 60. The nozzle of the air nozzle 61 is oriented in a direction between the -X direction and the -Z direction. The air nozzle 61 is connected to an air supply source 610. By supplying air from the air supply source 610 to the air nozzle 61, air can be sprayed from the air nozzle 61 onto the holding surface 200, for example, from 30 degrees above. Then, for example, by spraying air from the air nozzle 61 while spraying water from the water nozzle 60, the air sprayed from the air nozzle 61 flows over the surface of the water sprayed from the water nozzle 60 and supplied to the holding surface 200, thereby forming a water flow on the water on the holding surface 200.

Alternatively, the air nozzle 61 may be a mixed fluid nozzle integrated with the water nozzle 60, and capable of spraying two fluids, that is, a mixture of air and water.

The first cutting means 31 is provided with a cutting water nozzle 8 that sprays cutting water at the processing point where the cutting blade 310 and the upper surface 1400 of the wafer 140 come into contact. The cutting water nozzle 8 is connected to a cutting water supply source 9. By supplying cutting water from the cutting water supply source 9 to the cutting water nozzle 8, cutting water can be sprayed from the cutting water nozzle 8 toward the processing point.

2 Operation of the Cutting Apparatus The operation of the cutting apparatus 1 when cutting the wafer 140 using the cutting apparatus 1 will be described.
1 is placed on the holding surface 200, and the frame 141 is gripped and fixed using the four clamps 23. Then, the suction source 29 is operated to generate a suction force, which is transmitted to the holding surface 200, whereby the tape 142 is sucked onto the holding surface 200, and the wafer 140 is held on the holding surface 200.

Next, the cutting feed means 26 is used to move the chuck table 2 in the -X direction, and the wafer 140 held on the chuck table 2 is positioned below the imaging means 33.

After positioning the wafer 140 below the imaging means 33, the imaging means 33 is used to image the planned division line 1402 formed on the wafer 140. Then, based on the image of the planned division line 1402 that has been captured, the first cutting means 31 and the second cutting means 32 are appropriately moved in the Y-axis direction using the first Y-axis moving means 51 and the second Y-axis moving means 52 to align the first cutting means 31 and the second cutting means 32 with respect to the planned division line 1402 in the Y-axis direction.

Then, as shown in FIG. 2, while the cutting blades 310 and 320 are rotating, the first cutting means 31 is moved in the -Z direction using the first Z-axis moving means 41 and the second Z-axis moving means 42 shown in FIG. 1, so that the rotating cutting blades 310 and 320 come into contact with the planned division line 1402 of the wafer 140.

While the rotating cutting blades 310 and 320 are cutting into the planned dividing line 1402 of the wafer 140, the cutting feed means 26 is used to move the wafer 140 held on the chuck table 2 in the cutting feed direction (-X direction), which is the forward direction relative to the rotation direction of the cutting blades 310 and 320.
As a result, the wafer 140 and the cutting blades 310, 320 move relatively in the X-axis direction, and the wafer 140 is cut along the planned dividing lines 1402 of the wafer 140. At this time, the water nozzle 60 and the air nozzle 61 move together with the chuck table 2 in the cutting feed direction.

Cutting chips are generated when cutting the wafer 140. Therefore, during grinding of the wafer 140, water is sprayed from the water nozzle 60 in a direction between the -X direction and the -Z direction as shown in Fig. 2. This causes the water to flow over the upper surface 1400 of the wafer 140 in the forward direction (-X direction) relative to the cutting feed direction of the chuck table 2, and the water spreads over the upper surface 1400 of the wafer 140, forming a water layer 62 on the upper surface 1400 of the wafer 140 as shown in Fig. 3.
Furthermore, air is jetted from the air nozzle 61 in a direction between the -X direction and the -Z direction, and the air is jetted in the forward direction relative to the cutting feed direction onto the upper surface of the water layer 62 formed on the upper surface 1400 of the wafer 140. This forms a water flow on the upper surface 1400 of the wafer 140, and the cutting chips remaining in the water layer 62 formed on the upper surface 1400 of the wafer 140 can be pushed away from the upper surface 1400 of the wafer 140 to the -X direction side.

After cutting one planned division line 1402, the chuck table 2 is moved in the +X direction to return to its original position, and the first cutting means 31 and the second cutting means 32 are moved in the Y-axis direction, for example, by the first Y-axis moving means 51 and the second Y-axis moving means 52 by the distance between adjacent planned division lines 1402, and then the cutting blade 30 is similarly inserted into the planned division line 1402 and fed for cutting, thereby cutting the adjacent planned division lines 1402.

After cutting all of the planned dividing lines 1402 in the same direction formed on the wafer 140 in this manner, the chuck table 2 is rotated, for example, by 90 degrees using a rotation means (not shown), and then cutting is performed in the same manner, thereby cutting all of the planned dividing lines 1402 on the wafer 140. As a result, all of the planned dividing lines 1402 formed on the wafer 140 are cut.

In the cutting device 1, water is sprayed from the water nozzle 60 and air is sprayed from the air nozzle 61 during the grinding process of the wafer 140, thereby generating a water flow on the upper surface 1400 of the wafer 140, and grinding debris generated by the grinding process of the wafer 140 can be washed away from the upper surface 1400 of the wafer 140.

In addition, conventional cutting devices must be equipped with a cleaning unit (not shown) for cleaning the top surface 1400 of the wafer 140 after cutting, but in the cutting device 1, for example, when there are relatively few planned division lines 1402 formed on the wafer 140 and relatively little cutting debris is generated by the cutting process, the top surface 1400 of the wafer 140 can be cleaned using water sprayed from the water nozzle 60 and air sprayed from the air nozzle 61, thereby eliminating the need to clean the top surface 1400 of the wafer 140 using the cleaning unit. In this case, the cutting device 1 does not require the cleaning unit, and the cutting device can be made smaller.

The cutting device 1 may be an edge trimming device that performs annular cutting along the outer peripheral edge of the wafer.

1: Cutting device 10: Base 100: Cassette stage 11: Gate-type column 14: Work unit 140: Wafer 141: Frame 142: Tape 1400: Upper surface 1401: Device 1402: Planned division line 2: Chuck table 20: Suction part 200: Holding surface 21: Frame 210: Upper surface 23: Clamp 26: Cutting feed means 27: Cover 28: Bellows 29: Suction source 30: Cutting blade 31: First cutting means 32: Second cutting means 33: Imaging means 310: Cutting blade 311: Spindle housing 312: First spindle 320: Cutting blade 321: Spindle housing 322: Second spindle 41: First Z-axis moving means 42: Second Z-axis moving means 410: Ball screw 411: Guide rail 412: Z-axis motor 413: Lift plate 415: Rotating shaft 420: Ball screw 421: Guide rail 422: Z-axis motor 423: Lift plate 425: Rotating shaft 51: First Y-axis moving means 52: Second Y-axis moving means 510: Ball screw 511: Guide rail 513: Slide plate 520: Ball screw 521: Guide rail 522: Y-axis motor 523: Slide plate 60: Water nozzle 61: Air nozzle 600: Water supply source 610: Air supply source 62: Water layer 8: Cutting water nozzle 9: Cutting water supply source

Claims (3)

A cutting device comprising: a chuck table for holding a wafer on a holding surface; cutting means for cutting the wafer held on the holding surface, the cutting blade for cutting the wafer being disposed at a tip of a spindle; and cutting feed means for cutting the wafer by feeding the chuck table in a forward cutting feed direction relative to a rotation direction of the cutting blade,
a water nozzle extending parallel to the spindle and disposed upstream of the spindle in the cutting feed direction, for spraying water in a forward direction relative to the cutting feed direction of the chuck table being cut during cutting processing of the wafer , to form a water layer on the upper surface of the wafer held on the holding surface;
a cutting device comprising: an air nozzle extending parallel to the spindle and the water nozzle , positioned downstream of the water nozzle in the cutting feed direction, spraying water from the water nozzle to form a water layer while flowing air in a forward direction relative to the cutting feed direction of the chuck table on an upper surface of the water layer, thereby forming a water flow in the forward direction of the cutting feed direction. The cutting device according to claim 1, in which the water nozzle and the air nozzle are disposed adjacent to the chuck table and moved together with the chuck table in the cutting feed direction. The cutting device according to claim 1, wherein the air nozzle sprays a dual fluid mixture of air and water.

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