Cutting device

Abstract

The present application provides a cutting device which prevents the attachment of cutting chips. In a state in which a rotating cutting tool (310) cuts into a wafer (140) held by a chuck table (2), when the wafer (140) is subjected to cutting processing by moving the chuck table (2) in a cutting feed direction, i.e., an X direction, using a cutting feed unit (26), water is sprayed from a water nozzle (60) in a forward direction with respect to the cutting feed direction of the chuck table (2), i.e., an X direction, and air is sprayed from an air nozzle (61). Thus, a flow of water in the X direction is generated on an upper surface (1400) of the wafer (140), and cutting chips generated by the grinding processing of the wafer (140) are washed away from the upper surface (1400) of the wafer (140) in the X direction.

Description

Technical Field

[0001] This invention relates to a cutting device. Background Technology

[0002] A cutting apparatus that uses a cutting tool to cut a wafer held on a chuck table covers the upper surface of the wafer with water during cutting, so that the cutting chips generated during the wafer grinding process do not adhere to the upper surface of the wafer. As disclosed in Patent Document 1, the wafer is cut by feeding the chuck table while water is spread over the entire upper surface of the wafer.

[0003] However, the water flow on the upper surface of the wafer is small or nonexistent, and the gap between the lower surface of the spindle unit that rotates the cutting tool and the upper surface of the wafer is filled with water, thus the upper surface of the wafer and the lower surface of the spindle unit are joined by water.

[0004] Therefore, no flow occurs in the water on the upper surface of the wafer, and the cutting chips remain in the water layer on the upper surface of the wafer and adhere to the upper surface of the wafer.

[0005] Furthermore, as disclosed in Patent Documents 2 and 3, there are inventions that form a water tank and cover the entire upper surface of the wafer with water. In this case, the water on the upper surface of the wafer does not flow, thus causing cutting chips to adhere to the upper surface of the wafer.

[0006] Patent Document 1: Japanese Patent Application Publication No. 2005-222990

[0007] Patent Document 2: Japanese Patent Application Publication No. 2001-135596

[0008] Patent Document 3: Japanese Patent Application Publication No. 2017-094455

[0009] Therefore, the following problem exists in the cutting device: forming a water layer with flowing water on the upper surface of the wafer to prevent the adhesion of cutting chips. Summary of the Invention

[0010] The cutting apparatus of the present invention comprises: a chuck stage holding a wafer on a holding surface; a cutting unit having a cutting tool for cutting the wafer disposed at the front end of a spindle, the cutting unit cutting the wafer held on the holding surface; and a cutting feed unit cutting the wafer by cutting the chuck stage in a cutting feed direction relative to the rotation direction of the cutting tool, wherein the cutting apparatus comprises: a water nozzle extending parallel to the spindle and disposed upstream of the cutting feed direction, spraying water in a forward direction relative to the cutting feed direction of the chuck stage being cut, forming a water layer on the upper surface of the wafer held on the holding surface; and an air nozzle extending parallel to the spindle and the water nozzle, causing air to flow in a forward direction relative to the cutting feed direction on the upper surface of the water layer.

[0011] Preferably, in the above-described cutting device, the water nozzle and the air nozzle are arranged adjacent to the chuck table, so that the water nozzle and the air nozzle move together with the chuck table in the cutting feed direction.

[0012] The air nozzles described above can also spray a two-fluid mixture that mixes water with air.

[0013] In the cutting apparatus of the present invention, by spraying water from a water nozzle and air from an air nozzle during the grinding process of the wafer, water flow can be generated on the upper surface of the wafer, thereby washing away the grinding chips generated during the grinding process of the wafer from the upper surface of the wafer. Attached Figure Description

[0014] Figure 1 It is a three-dimensional view showing the entire cutting device.

[0015] Figure 2 This is a cross-sectional view of the cutting unit and the holding unit.

[0016] Figure 3 This is a cross-sectional view of the cutting unit and the holding unit.

[0017] Label Explanation

[0018] 1: Cutting device; 10: Base; 100: Carrier stage; 11: Portal column; 14: Workpiece unit; 140: Wafer; 141: Frame; 142: Belt; 1400: Upper surface; 1401: Device; 1402: Predetermined dividing line; 2: Chuck stage; 20: Suction part; 200: Holding surface; 21: Frame; 210: Upper surface; 23: Fixture; 26: Cutting feed unit; 27: Cover; 28: Fold; 29: Suction source; 30: Cutting tool; 31: First cutting unit; 32: Second cutting unit; 33: Imaging unit; 310: Cutting tool; 311: Spindle housing; 312: First spindle; 320: Cutting tool; 321: Spindle housing; 322: Second spindle; 41 410: 1st Z-axis moving unit; 411: 2nd Z-axis moving unit; 412: Z-axis motor; 413: Lifting plate; 415: Rotation axis; 420: Ball screw; 421: Guide rail; 422: Z-axis motor; 423: Lifting plate; 425: Rotation axis; 51: 1st Y-axis moving unit; 52: 2nd Y-axis moving unit; 510: Ball screw; 511: Guide rail; 513: Sliding plate; 520: Ball screw; 521: Guide rail; 522: Y-axis motor; 523: Sliding 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. Detailed Implementation

[0019] 1. Structure of the cutting device

[0020] Figure 1 The cutting apparatus 1 shown is a cutting apparatus that uses a first cutting unit 31 and a second cutting unit 32 to cut a wafer 140. 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 workpiece unit 14 that integrates the wafer 140, the frame 141, and the tape 142. Multiple mutually perpendicular dividing lines 1402 are formed on the upper surface 1400 of the wafer 140, and a device 1401 is disposed in the area divided by the dividing lines 1402. The structure of the cutting apparatus 1 will be described below.

[0021] like Figure 1 As shown, the cutting device 1 has a base 10 extending in the horizontal direction. The portion of the base 10 in the +X direction and the -Y direction becomes a box-mounting stage 100, on which a box (not shown) containing the workpiece unit 14 is mounted.

[0022] A portal column 11 is erected on the -X direction side of the base 10. A first Z-axis moving unit 41, which supports the first cutting unit 31 and is capable of being raised and lowered, is provided on the +X and +Y direction sides of the portal column 11.

[0023] The first Z-axis moving unit 41 includes: a ball screw 410 having a rotation axis 415 in the Z-axis direction; a guide rail 411 arranged parallel to the ball screw 410; a Z-axis motor 412 that causes the ball screw 410 to rotate about the rotation axis 415; and a lifting plate 413, the nut on its side of which is screwed into the ball screw 410, and the lifting plate 413 slidingly contacting the guide rail 411. A main shaft housing 311 is connected to the lifting plate 413.

[0024] By using the Z-axis motor 412 to rotate the ball screw 410, the lifting plate 413 moves in the Z-axis direction while being guided by the guide rail 411, and the main shaft housing 311 connected to the lifting plate 413 moves in the Z-axis direction.

[0025] The first cutting unit 31 includes a cutting tool 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 tool 310 is mounted on the -Y direction side of the first spindle 312. The first spindle 312 is connected to an electric motor (not shown) or the like, and when the first spindle 312 is driven to rotate by the electric motor, the cutting tool 310 connected to the first spindle 312 rotates.

[0026] An imaging unit 33, equipped with a camera or the like, is provided adjacent to the cutting tool 310. The imaging unit 33 can be used to photograph the predetermined dividing lines 1402 formed on the wafer 140 held on the holding surface 200 of the chuck stage 2.

[0027] A second Z-axis moving unit 42, which supports the second cutting unit 32 and is capable of being raised and lowered, is provided on the +X and -Y directions sides of the portal column 11.

[0028] The second Z-axis moving unit 42 is configured similarly to the first Z-axis moving unit 41. Specifically, the second Z-axis moving unit 42 includes: a ball screw 420 having a rotation axis 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 about the rotation axis 425; and a lifting plate 423, whose side nut is screwed into the ball screw 420, and the lifting plate 423 slides in contact with the guide rail 421. A main shaft housing 321 is connected to the lifting plate 423.

[0029] When the ball screw 420 is rotated by the Z-axis motor 422, the lifting plate 423 moves in the Z-axis direction while being guided by the guide rail 421. At the same time, the spindle housing 321 connected to the lifting plate 423 moves in the Z-axis direction.

[0030] The second cutting unit 32 is configured similarly to the first cutting unit 31. That is, the second cutting unit 32 includes a cutting tool 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 tool 320 is rotatably mounted on the +Y direction side of the second spindle 322. The second spindle 322 is connected to a motor (not shown), and when the second spindle 322 is driven to rotate by the motor, the cutting tool 320 mounted on the second spindle 322 rotates.

[0031] The portal column 11 is provided with a first Y-axis moving unit 51 that moves the first cutting unit 31 in the Y-axis direction and a second Y-axis moving unit 52 that moves the second cutting unit 32 in the Y-axis direction.

[0032] The first Y-axis moving unit 51 includes: a ball screw 510 having a center 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 sliding plate 513, the nut on its side of which is screwed into the ball screw 510, and the sliding plate 513 slidingly contacts the guide rail 511. The sliding plate 513 supports the first Z-axis moving unit 41.

[0033] When the ball screw 510 is rotated using the Y-axis motor, the sliding plate 513 is guided by the guide rail 511 and moves in the Y-axis direction. At the same time, the first Z-axis moving unit 41 supported on the sliding plate 513 and the first cutting unit 31 of the lifting plate 413 supported on the first Z-axis moving unit 41 move together in the Y-axis direction.

[0034] The second Y-axis moving unit 52 is configured in the same way as the first Y-axis moving unit 51. That is, the second Y-axis moving unit 52 includes: a ball screw 520 having a shaft 525 in the Y-axis direction; a Y-axis motor 522 that rotates the ball screw 520; a guide rail 521 that is arranged parallel to the ball screw 520; and a sliding plate 523, the nut on its side of which is screwed into the ball screw 520, and the sliding plate 523 slidingly contacts the guide rail 521.

[0035] When the ball screw 520 is rotated by the Y-axis motor 522, the sliding plate 523 is guided by the guide rail 521 to move in the Y-axis direction. Simultaneously, the second Z-axis moving unit 42 supported on the sliding plate 523 and the second cutting unit 32 of the lifting plate 423 supported on the second Z-axis moving unit 42 move together in the Y-axis direction. Furthermore, the guide rail 521 also serves as a guide for the movement of the sliding plate 513 of the first Y-axis moving unit 51. Similarly, the guide rail 511 of the first Y-axis moving unit 51 also serves as a guide for the movement of the sliding plate 523 of the second Y-axis moving unit 52.

[0036] A chuck worktable 2 is mounted on the base 10. The chuck worktable 2 has a circular plate-shaped suction part 20 and an annular frame 21 that supports the suction part 20. The upper surface of the suction part 20 is a holding surface 200 that holds the workpiece unit 14, and the upper surface 210 of the frame 21 is formed coplanarly with the holding surface 200.

[0037] Four clamps 23 are arranged adjacent to the chuck table 2, surrounding the chuck table 2 from all sides. The workpiece unit 14 is placed on the retaining surface 200 with the upper surface 1400 facing the +Z direction with the belt 142 in contact with the retaining surface 200. The four clamps 23 hold the frame 141 from all sides, thereby fixing the workpiece unit 14 on the retaining surface 200.

[0038] The chuck stage 2 is connected to the suction source 29. By actuating the suction source 29, the resulting attraction force is transmitted to the holding surface 200. For example, by placing the workpiece unit 14 on the holding surface 200 and actuating the suction source 29, the wafer 140 can be attracted and held on the holding surface 200.

[0039] Additionally, the chuck table 2 is connected to a rotary unit (not shown). This rotary unit allows the chuck table 2 to rotate.

[0040] The cutting device 1 includes a cutting feed unit 26 that moves the chuck stage 2 horizontally in the X-axis direction. For example, when the wafer 140 is held on the holding surface 200 of the chuck stage 2, the cutting feed unit 26 is used to move the chuck stage 2 horizontally in the X-axis direction, thereby enabling the wafer 140 to move in the X-axis direction.

[0041] A cover 27 is provided around the chuck worktable 2, and the cover 27 is connected to the pleats 28 in a telescopic manner.

[0042] 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, and the fold 28 extends and retracts.

[0043] The cutting device 1 includes a water nozzle 60. The water nozzle 60 is configured to extend parallel to the Y-axis direction, which is the extending direction of the first spindle 312 and the second spindle 322, and is positioned on the upstream side of the cutting feed direction, i.e., the +X direction side. Figure 2 As shown, the water nozzle 60 is positioned horizontally adjacent to the chuck table 2 and fixed above the clamp 23 located on the +X direction side of the chuck table 2. Furthermore, the spray nozzle 60 faces the direction between the -X and -Z directions.

[0044] The water nozzle 60 is connected to the water supply source 600. By supplying water from the water supply source 600 to the water nozzle 60, water can be sprayed toward the holding surface 200 of the chuck table 2.

[0045] The cutting device 1 includes an air nozzle 61. The air nozzle 61 is configured to extend parallel to the first spindle 312, the second spindle 322, and the water nozzle 60. The nozzle orifice of the air nozzle 61 faces a direction between the -X and -Z directions. The air nozzle 61 is connected to an air supply source 610. By supplying air to the air nozzle 61 from the air supply source 610, air can be sprayed from the air nozzle 61 onto the holding surface 200 from, for example, an angle of 30 degrees above it. Furthermore, for example, by spraying water from the water nozzle 60 while simultaneously spraying air from the air nozzle 61, 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 creating a water flow in the water on the holding surface 200.

[0046] Air nozzle 61 can also replace the above structure and is a mixed fluid nozzle integrated with water nozzle 60, capable of spraying a two-fluid mixture of air and water.

[0047] The first cutting unit 31 is equipped with a cutting water nozzle 8 that sprays cutting water at the machining point where the cutting tool 310 contacts the upper surface 1400 of the wafer 140. 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 machining point.

[0048] 2. Operation of the cutting device

[0049] The operation of the cutting device 1 when cutting the wafer 140 is described.

[0050] When using the cutting device 1 to cut the wafer 140, firstly, Figure 1The workpiece unit 14 shown is placed on the holding surface 200, and the frame 141 is held and fixed by four clamps 23. Then, the attractive force generated by the attraction source 29 is transmitted to the holding surface 200, thereby attracting the strip 142 to the holding surface 200 and holding the wafer 140 on the holding surface 200.

[0051] Next, the cutting feed unit 26 is used to move the chuck stage 2 in the -X direction, positioning the wafer 140 held by the chuck stage 2 below the imaging unit 33.

[0052] After positioning the wafer 140 below the imaging unit 33, the imaging unit 33 is used to image the pre-defined segmentation line 1402 formed on the wafer 140. Then, based on the image of the pre-defined segmentation line 1402, the first cutting unit 31 and the second cutting unit 32 are moved appropriately in the Y-axis direction using the first Y-axis moving unit 51 and the second Y-axis moving unit 52 to align the first cutting unit 31 and the second cutting unit 32 with respect to the pre-defined segmentation line 1402 in the Y-axis direction.

[0053] Then, as Figure 2 As shown, when the cutting tools 310 and 320 are rotating, using Figure 1 The first Z-axis moving unit 41 and the second Z-axis moving unit 42 shown move the first cutting unit 31 in the -Z direction, so that the rotating cutting tools 310 and 320 come into contact with the predetermined dividing line 1402 of the wafer 140.

[0054] With the rotating cutting tools 310 and 320 cutting into the pre-defined dividing line 1402 of the wafer 140, the cutting feed unit 26 is used to move the wafer 140, which is held on the chuck stage 2, in the cutting feed direction (-X direction), which is the same direction as the rotation direction of the cutting tools 310 and 320.

[0055] As a result, the wafer 140 and the cutting tools 310 and 320 move relative to each other in the X-axis direction, cutting the wafer 140 along the predetermined dividing line 1402. At this time, the water nozzle 60 and the air nozzle 61 move together with the chuck table 2 in the cutting feed direction.

[0056] When the wafer 140 is machined, cutting chips are generated. Therefore, during the grinding process of the wafer 140, as... Figure 2 As shown, water is sprayed from the water nozzle 60 in a direction between the -X and -Z directions. Consequently, the water flows on the upper surface 1400 of the wafer 140 in the direction forward (-X direction) relative to the cutting feed direction of the chuck table 2, and the water covers the entire upper surface 1400 of the wafer 140. Figure 3As shown, a water layer 62 is formed on the upper surface 1400 of the wafer 140.

[0057] Furthermore, air is ejected from the air nozzle 61 in a direction between the -X and -Z directions, and air is also ejected onto the upper surface of the water layer 62 formed on the upper surface 1400 of the wafer 140 in a direction parallel to the cutting feed direction. As a result, a water flow is formed on the upper surface 1400 of the wafer 140, which can wash away the cutting chips trapped in the water layer 62 formed on the upper surface 1400 of the wafer 140 from the upper surface 1400 of the wafer 140 towards the -X direction.

[0058] After cutting one predetermined dividing line 1402, the chuck table 2 is moved in the +X direction to return to its original position. For example, the first Y-axis moving unit 51 and the second Y-axis moving unit 52 are used to move the first cutting unit 31 and the second cutting unit 32 in the Y-axis direction by the amount of interval between adjacent predetermined dividing lines 1402. Then, the cutting tool 30 is similarly cut into the predetermined dividing line 1402 to perform cutting feed, thereby performing cutting machining on the adjacent predetermined dividing lines 1402.

[0059] In this way, after all the predetermined dividing lines 1402 formed in the same direction on the wafer 140 have been cut, for example, the chuck stage 2 is rotated by 90 degrees using a rotary unit (not shown), and then the cutting process is performed in the same way, thereby cutting all the predetermined dividing lines 1402 on the wafer 140. Thus, all the predetermined dividing lines 1402 formed on the wafer 140 are cut.

[0060] In the cutting apparatus 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 flow of water on the upper surface 1400 of the wafer 140, which can wash away the grinding chips generated by the grinding process of the wafer 140 from the upper surface 1400 of the wafer 140.

[0061] Furthermore, conventional cutting apparatuses require a cleaning unit (not shown) to clean the upper surface 1400 of the wafer 140 after cutting. However, in cutting apparatus 1, for example, when there are fewer predetermined dividing lines 1402 formed on the wafer 140 and fewer cutting chips generated from the cutting process, water sprayed from water nozzle 60 and air sprayed from air nozzle 61 are used to clean the upper surface 1400 of the wafer 140. This eliminates the need for the cleaning unit. In this case, cutting apparatus 1 does not require the cleaning unit, enabling miniaturization of the cutting apparatus.

[0062] The cutting device 1 can also be an edge trimming device that performs cutting operations in a ring along the outer periphery of the wafer.

Claims

1. A cutting device, comprising: A chuck stage that holds the wafer on its holding surface; The cutting unit has a cutting tool for cutting the wafer at the front end of the spindle, and the cutting unit cuts the wafer held by the holding surface; as well as The cutting feed unit feeds the chuck table in a cutting feed direction to cut the wafer. This cutting feed direction is clockwise relative to the rotation direction of the cutting tool. in, The cutting device has the following features: A water nozzle, which extends parallel to the spindle and is disposed upstream of the spindle in the cutting feed direction, sprays water in the forward direction relative to the cutting feed direction of the chuck table being cut during wafer cutting, forming a water layer on the upper surface of the wafer held by the holding surface. as well as An air nozzle, which extends parallel to the spindle and the water nozzle and is positioned downstream of the water nozzle in the cutting feed direction, sprays water from the water nozzle to form the water layer, while the air nozzle causes air to flow in the forward direction relative to the cutting feed direction of the chuck table on the upper surface of the water layer.

2. The cutting device according to claim 1, wherein, The water nozzle and the air nozzle are arranged adjacent to the chuck table so that the water nozzle and the air nozzle move together with the chuck table in the cutting feed direction.

3. The cutting device according to claim 1, wherein, The air nozzle sprays water to mix with the air to create a two-fluid mixture.

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