JP2022022831A - Cutting device and chuck table - Google Patents

Abstract

To provide a cutting device which inhibits a waste liquid mixed with chips from entering a chuck table from its outer periphery and causing contamination in the chuck table when a cutting groove is formed at a wafer, and to provide the chuck table.SOLUTION: A cutting device 1 is provided that includes at least a chuck table 34 which holds a wafer 10 and cutting means 20 which performs cutting to the wafer 10 held by the chuck table 34 while supplying processing water to the wafer 10. In the cutting device 1, the chuck table 34 includes: a porous plate 35 including a suction surface 35A which suctions and holds the wafer 10; and a frame body 36 which encloses the porous plate 35 while exposing the suction surface 35A. The porous plate 35 includes: a center area 35a which suctions and holds the center side of the wafer 10; and an outer peripheral area 35c which encloses the center area 35a through a partition wall 35b. The frame body 36 is formed with an annular water supply part 36d which supplies water L to an outer periphery 10c of the wafer 10 suctioned and held by the suction surface 35A to form a wafer seal S.SELECTED DRAWING: Figure 5

Description

The present invention relates to a chuck table that sucks and holds a wafer, and a cutting apparatus that includes at least a chuck table and a cutting means that performs cutting while supplying processing water to the wafer held by the chuck table.

A wafer in which a plurality of devices such as ICs and LSIs are partitioned by a scheduled division line and formed on the front surface is divided into individual device chips by a dicing device after the back surface is ground by a grinding device to form a desired thickness. Used for electrical equipment such as mobile phones and personal computers.

In addition, the wafer is not completely cut, and a so-called half-cut is performed to form a cutting groove with a depth corresponding to the finished thickness of the wafer on the planned division line, and then a protective tape is attached to the surface of the wafer. A technique has been proposed in which the back surface of a wafer is ground to a finished thickness and the dividing groove is exposed on the back surface to divide the wafer into individual device chips (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2000-021820

However, when a cutting groove is formed along the planned division line formed on the surface of the wafer while supplying processing water, the waste liquid mixed with cutting chips enters from the outer periphery of the chuck table that sucks and holds the wafer and presses the chuck table. There is the problem of contamination. In particular, it becomes a problem when the cutting process is performed by sucking and holding the adhesive tape or the like on the chuck table without sticking it to the wafer.

The present invention has been made in view of the above facts, and the main technical problem thereof is that when forming a cutting groove on the surface of the wafer, waste liquid mixed with cutting chips enters from the outer periphery of the chuck table and the chuck table is formed. It is an object of the present invention to provide a cutting device capable of suppressing contamination and a chuck table.

In order to solve the above-mentioned main technical problem, according to the present invention, at least a chuck table for holding a wafer and a cutting means for performing cutting while supplying processing water to the wafer held on the chuck table are provided. The chuck table is a cutting device, and the chuck table includes a porous plate having a suction surface for sucking and holding a wafer, and a frame body that exposes the suction surface and surrounds the porous plate. A central region that sucks and holds the central side of the weight and an outer peripheral region that surrounds the central region via a partition wall are provided, and water is supplied to the outer periphery of the weight that is sucked and held by the suction surface. A cutting device is provided in which an annular water supply portion for forming a water seal is formed.

The frame is provided with an outer peripheral suction path that supplies a suction negative pressure to the suction surface of the outer peripheral region of the porous plate, and water is supplied from a water supply source to the outer peripheral region of the porous plate via the outer peripheral suction path. It is preferable to provide a cleaning means for cleaning the outer peripheral region.

Further, according to the present invention, a porous plate having a suction surface for sucking and holding the wafer and a frame body for exposing the suction surface and surrounding the porous plate are provided, and the porous plate is the center of the wafer. A central region that sucks and holds the side and an outer peripheral region that surrounds the central region via a partition wall are provided, and water is supplied to the outer periphery of the wafer that is sucked and held by the suction surface to the frame. A chuck table is provided in which an annular water supply portion forming a seal is formed.

The frame is provided with an outer peripheral suction path that supplies a suction negative pressure to the suction surface of the outer peripheral region of the porous plate, and the outer peripheral suction path is provided in the outer peripheral region of the porous plate via the outer peripheral suction path. It is preferable that the water supply path for supplying water is connected.

The cutting device of the present invention is a cutting device including at least a chuck table for holding a wafer and a cutting means for performing cutting while supplying processing water to the wafer held on the chuck table. The table includes a porous plate having a suction surface for sucking and holding the wafer, and a frame body that exposes the suction surface and surrounds the porous plate, and the porous plate sucks and holds the center side of the wafer. The frame is provided with a central region and an outer peripheral region surrounding the central region via a partition wall, and the frame has an annular shape in which water is supplied to the outer periphery of the wafer sucked and held by the suction surface to form a water seal. Since the water supply section is formed, it is possible to prevent the waste liquid mixed with cutting chips from entering from the outer peripheral side of the chuck table when forming a cutting groove in the planned division line formed on the surface of the wafer, and the chuck is chucked. The problem of table contamination is resolved.

Further, the chuck table of the present invention includes a porous plate having a suction surface for sucking and holding the wafer, and a frame body that exposes the suction surface and surrounds the porous plate. The porous plate is made of a wafer. A central region that sucks and holds the central side and an outer peripheral region that surrounds the central region via a partition wall are provided, and water is supplied to the outer periphery of the wafer that is sucked and held by the suction surface of the frame. Since the annular water supply part that forms the water seal is formed, the waste liquid mixed with cutting chips enters from the outer peripheral side of the chuck table when forming the cutting groove in the planned division line formed on the surface of the wafer. This is suppressed and the problem that the chuck table is contaminated is solved.

It is a perspective view of the cutting apparatus of this embodiment. It is an exploded perspective view of the chuck table arranged in the cutting apparatus shown in FIG. 1. FIG. 2 is a partially enlarged cross-sectional view of the chuck table shown in FIG. 2, and is a conceptual diagram showing a suction negative pressure path and a water supply path. It is a perspective view which shows the mode of holding a wafer in a chuck table. It is a partially enlarged sectional view which shows the mode at the time of a cutting process. It is a partially enlarged sectional view which shows the mode of cleaning a chuck table.

Hereinafter, an embodiment relating to a chuck table configured based on the present invention and an embodiment relating to a cutting device provided with the chuck table as a holding means will be described in detail with reference to the attached drawings.

FIG. 1 shows a perspective view showing an outline of the internal structure of the cutting device 1 excluding the device housing and the like, and a perspective view of the wafer 10 to be cut by the cutting device 1.

As shown in FIG. 1, the cutting apparatus 1 includes a base 1A, a portal frame 1B disposed on the base 1A, a cutting means 20 for cutting a wafer 10 as a workpiece, and a wafer. The holding means 30 provided with the chuck table 34 for holding the 10, the X-axis feeding means 40 for machining and feeding the cutting means 20 and the holding means 30 relatively in the X-axis direction, and the cutting means 20 and the holding means 30. The Y-axis feed means 50, which is orthogonal to the X-axis direction and relatively processes and feeds in the Y-axis direction forming a horizontal plane together with the X-axis direction, and the cutting means 20 and the holding means 30 are orthogonal to the X-axis direction and the Y-axis direction. It includes a Z-axis feed means 60 that cuts and feeds relatively in the Z-axis direction, an image pickup means 28 that captures an image of the wafer 10 held by the holding means 30, and a control means 100. Although the control means 100 is described outside the cutting device 1 for convenience of explanation, it is actually housed inside the cutting device 1.

The holding means 30 includes a rectangular X-axis direction movable plate 31 movably mounted on the base 1A in the X-axis direction, a cylindrical member 32 arranged on the upper surface of the X-axis direction movable plate 31, and a cylinder. It includes a cover member 33 arranged on the upper part of the member 32, and a chuck table 34 arranged so as to extend upward from the center of the cover member 33. When cutting the wafer 10, the back surface 10b side of the wafer 10 is placed on the chuck table 34 and sucked and held. The chuck table 34 is configured to be rotatable by a rotation driving means (not shown). Although omitted in FIG. 1, bellows members are arranged on both sides of the cover member 33 in the X-axis direction, and the X-axis feeding means 40 is operated to expand and contract the bellows member and chuck table. 34 is moved forward and backward in the X-axis direction. Further, the waste liquid supplied at the time of cutting and mixed with cutting chips flows on the bellows member and is collected through a predetermined waste liquid recovery path (not shown).

The details of the chuck table 34 will be described more specifically with reference to FIG. 2. The upper part of FIG. 2 shows an enlarged perspective view of a part of the chuck table 34 disassembled, and the lower part shows a perspective view of the chuck table 34 after assembly. As shown in the figure, the chuck table 34 includes a porous plate 35 having a suction surface 35A for sucking and holding the wafer 10, and a frame body 36 that exposes the suction surface 35A of the porous plate 35 and surrounds the suction surface other than the suction surface 35A. , Is equipped.

The porous plate 35 is a disk-shaped member made of a breathable material, for example, a porous semix. The porous plate 35 has a triple layer including a central region 35a that sucks and holds the central side of the wafer 10 and an outer peripheral region 35c that surrounds the central region 35a via an annular partition wall 35b and sucks and holds the outer peripheral side of the wafer 10. It has a structure. The area of the central region 35a is preferably as large as possible as compared with the outer peripheral region 35c, and it is more preferable that the central region 35a sucks and holds substantially the entire back surface 10b of the wafer 10. Further, in the porous plate 35 of the present embodiment, the central region 35a is formed of a porous having a coarser grain (for example, about # 100) than the outer peripheral region 35c, and the outer peripheral region 35b is formed of a porous having a finer mesh (for example, about # 320). The partition wall 35b is made of a non-breathable ceramic that blocks between the central region 35a and the outer peripheral region 35c.

As shown in the figure, the frame body 36 is formed with a recess 36a surrounding the porous plate 35 by the outer peripheral wall portion 36b and the bottom portion 36c. An annular water supply portion 36d is formed on the upper surface of the outer peripheral wall portion 36b to supply water to the outer periphery of the wafer held by the suction surface 35A of the porous plate 35 to form a water seal. The water supply unit 36d of the present embodiment is provided with an annular groove, and a plurality of water supply holes 36e are evenly arranged at the bottom of the groove.

The bottom portion 36c of the frame body 36 includes a central negative pressure supply hole 36f and a central groove portion 36g for supplying a suction negative pressure to the central region 35a of the porous plate 35 housed in the concave portion 36a, and an outer peripheral region 35c of the porous plate 35. A plurality of outer peripheral negative pressure supply holes 36h and outer peripheral groove portions 36i in which the outer peripheral negative pressure supply holes 36h are formed are formed. When the porous plate 35 is housed in the recess 36a of the frame body 36, the back surface of the central region 35a of the porous plate 35 faces the central groove portion 36g of the frame body 36, and the back surface of the outer peripheral region 35c of the porous plate 35 is the outer periphery of the frame body 36. It faces the groove 36i.

As shown on the lower side of FIG. 2, the porous plate 35 is housed in the frame body 36, and the suction surface 35A side is appropriately ground to appropriately grind the suction surface 35A of the porous plate 35 and the upper surface of the outer peripheral wall portion 36b of the frame body 36. Is adjusted to be flush with each other.

With reference to a partially enlarged cross-sectional view shown in FIG. 3, a configuration for supplying a suction negative pressure to the suction surface 35A of the porous plate 35 and a configuration for supplying water to the water supply unit 36d formed in the frame body 36 will be described. do.

The first negative pressure supply source 71 is connected to the central negative pressure supply hole 36f that supplies the negative pressure Vm1 to the central groove portion 36g facing the back surface of the central region 35a of the porous plate 35 via the first negative pressure supply path 36j. The second negative pressure supply source 72 is provided in the outer peripheral negative pressure supply hole 36h for supplying the negative pressure Vm2 to the outer peripheral groove portion 36i facing the back surface of the outer peripheral region 35c of the porous plate 35 via the second negative pressure supply path 36k. Is connected, and the water supply source 73 is connected to the water supply hole 36e for supplying the water L to the water supply portion 36d formed on the upper surface of the outer peripheral wall portion 36b of the frame body 36 via the first water supply passage 36m. Has been done. Further, as shown in the figure, a second water supply path 36n for supplying water L from the water supply source 73 is connected to the second negative pressure supply path 36k. Further, the first valve 37a is on the first negative pressure supply path 36j, the second valve 37b is on the second negative pressure supply path 36k, and the third valve 37c is on the first water supply path 36m. A fourth valve 37d is formed on the second water supply path 36n. Each of the above-mentioned valves is an on-off valve, which may be controlled by the above-mentioned control means 100 or may be opened / closed by an operator.

In the illustrated embodiment, the negative pressure supply source for supplying the suction negative pressure to the porous plate 35 is composed of the first negative pressure supply source 71 and the second negative pressure supply source 72. The negative pressure may be supplied from one negative pressure supply source to the first negative pressure supply path 36j and the second negative pressure supply path 36k without limitation. Further, although the water L is supplied from one water supply source 73 to the first water supply passage 36m and the second water supply passage 36n, two water supply sources are prepared and connected to each. You may do it.

Returning to FIG. 1 and continuing the description, the cutting means 20 is a means for performing cutting on the wafer 10 sucked and held by the chuck table 34, via the Y-axis feeding means 50 and the Z-axis feeding means 60. It is supported by the portal frame 1B. The cutting means 20 is a spindle housing 20A that rotatably holds the spindle 22, an annular cutting blade 21 mounted on the tip of the spindle 22, a blade cover 23 that covers the cutting blade 21, and a chuck table 34 for suction holding. It is provided with a processing water supply unit 24 for supplying processing water to the waiha 10. The spindle housing 20A houses an electric motor as a rotational drive source for rotating the spindle 22 (not shown).

The X-axis feeding means 40 is arranged on the base 1A, converts the rotary motion of the pulse motor 42 into a linear motion via the ball screw 44, transmits the linear motion to the movable plate 31 in the X-axis direction, and is transmitted on the base 1A. The chuck table 34 arranged on the movable plate 31 in the X-axis direction is moved back and forth in the X-axis direction along the guide rails 46 and 46.

The Y-axis feeding means 50 includes a ball screw mechanism, a pair of guide rails 52 extending in the Y-axis direction arranged on the portal frame 1B, and a ball screw 54 arranged in parallel with the guide rail 52. A Y-axis moving base 56 having a nut portion (not shown) that is advanced and retracted by the ball screw 54 on the back surface, and a pulse motor 58 that rotationally drives the ball screw 54 are provided. The Y-axis moving base 56 is guided in the Y-axis direction by the guide rail 52. The Y-axis feeding means 50 rotates the ball screw 54 by the pulse motor 58 to move the Y-axis moving base 56 in the Y-axis direction, and is supported by the Y-axis moving base 56 to support the cutting means 20. The shaft feed means 60 is moved in the Y-axis direction.

The Z-axis feed means 60 includes a pair of guide rails (not shown) arranged on the Y-axis moving base 56 and extending in the Z-axis direction, and a ball screw arranged in parallel with the guide rails (not shown). ), A Z-axis moving base 62 having a nut (not shown) screwed with the ball screw on the back surface, and a pulse motor 64 which is a power for rotating the ball screw. The Z-axis feed means 60 is supported by the Z-axis moving base 62 by rotating the ball screw with the pulse motor 64 to move the Z-axis moving base 62 in the Z-axis direction along the guide rail. The cutting means 20 is moved in the Z-axis direction.

The image pickup means 28 is integrally configured with the spindle housing 20A of the cutting means 20. Therefore, the X-axis feed means 40, the Y-axis feed means 50, and the Z-axis feed means 60 are operated to hold the image pickup means 28 together with the cutting means 20 in the X-axis direction and the Y-axis direction relative to the holding means 30. , Can be moved in the Z-axis direction. The image pickup means 28 is arranged at a position corresponding to the cutting blade 21 of the cutting means 20 in the X-axis direction, and is the center position of the region imaged by the image pickup means 28 and the Y coordinate position cut by the cutting blade 21. Match.

The cutting device 1 includes a rotation angle position detecting means for detecting the rotation angle position of the chuck table 34, an X-axis coordinate position detecting means for detecting the position (X coordinate position) of the chuck table 34 in the X-axis direction, and a cutting means 20. A Y-axis coordinate position detecting means for detecting a position in the Y-axis direction (Y-coordinate position) and a Z-axis coordinate position detecting means for detecting a position in the Z-axis direction (Z-coordinate position) of the cutting means 20 are provided ( The rotation angle position and X-axis coordinate position of the chuck table 34, the Y-axis coordinate position of the cutting means 20, and the Z-axis coordinate position are precisely detected and sent to the control means 100.

The control means 100 is configured by a computer and temporarily stores a central processing unit (CPU) that performs arithmetic processing according to a control program, a read-only memory (ROM) that stores a control program and the like, detection values, calculation results, and the like. It has a readable and writable random access memory (RAM), an input interface, and an output interface (details are not shown). The control means 100 of the present embodiment includes the above-mentioned cutting means 20, image pickup means 28, X-axis feed means 40, Y-axis feed means 50, Z-axis feed means 60, and rotation angle position detection means (not shown). , X-axis coordinate position detecting means, Y-axis coordinate position detecting means, and Z-axis coordinate position detecting means are connected, and cutting is performed at a desired position of a wafer 10 sucked and held by a chuck table 34 at a desired depth. Can be applied.

In addition to FIG. 1, the mode of cutting the wafer 10 will be described more specifically with reference to FIGS. 4 and 5. In the wafer 10, a plurality of devices 12 are partitioned by a scheduled division line 14 and formed on the surface 10a. As shown in FIG. 4, when the cutting process is performed, the back surface 10b of the wafer 10 is turned downward and placed on the suction surface 35A of the porous plate 35. In this embodiment, a protective member such as an adhesive tape is not arranged on the back surface 10b side of the wafer 10. Further, the diameter of the porous plate 35 forming the suction surface 35A is set according to the diameter of the wafer 10 which is the workpiece, and when the wafer 10 is placed on the chuck table 34, the lower portion of FIG. 4 As shown on the side, the wafer 10 is surrounded by the water supply unit 36d of the frame body 36.

With the wafer 10 placed on the chuck table 34 configured as described above, the first negative pressure supply source 71 and the second negative pressure supply source 72 shown in FIG. 5 are operated, and the third valve 37d is closed. The first valve 37a and the second valve 37b are opened. As a result, the suction negative pressure Vm1 acts on the central region 35a of the porous plate 35, the suction negative pressure Vm2 acts on the outer peripheral region 35c, and the entire wafer 10 is suction-held on the suction surface 35A of the porous plate 35. By the way, as described above, although the first negative pressure supply source 71 and the second negative pressure supply source 72 are composed of negative pressure supply sources having the same performance, the central region 35a of the porous plate 35 is the eye. Since it is formed of the coarse porous material, a strong negative pressure Vm1 acts on the surface side of the porous plate 35. On the other hand, the outer peripheral region 35c is formed of a fine-grained porous, and a weak negative pressure Vm2 acts on the surface side of the porous plate 35 as compared with the negative pressure Vm1.

Next, the X-axis feed means 40 shown in FIG. 1 is operated to position the chuck table 34 directly under the image pickup means 28, detect the position of the scheduled division line 14 formed on the surface 10a of the wafer 10, and detect the position of the scheduled division line 14 and the chuck table. The wafer 10 is rotated by the rotation driving means for rotating 34 to align the scheduled division line 14 in a predetermined direction in the X-axis direction. At this time, the thickness of the wafer 10 may be detected. Then, the detected position information of the scheduled division line 14 is stored in the control means 100 (alignment step).

Based on the position information of the scheduled division line 14 detected by the alignment step described above, the X-axis feed means 40 and the Y-axis feed means 50 are operated to form the scheduled split line 14 in the predetermined direction formed on the surface 10a of the wafer 10. The cutting blade 21 of the cutting means 20 is positioned above the machining start position of. Next, as shown in FIG. 5, the third valve 37c is opened, the water supply source 73 is operated, and the water L is sent to the upper surface of the outer peripheral wall portion 36b of the frame body 36 via the first water supply passage 36m. It is supplied to the formed water supply unit 36d. In the water L supplied to the water supply unit 36d, the water supply unit 36d is formed in an annular shape along the outer edge of the porous plate 35, so that an annular water seal S is formed along the outer peripheral edge 10c of the wafer 10. To.

Next, as shown in FIG. 5, the electric motor of the cutting means 20 is operated to rotate the cutting blade 21 in the direction indicated by the arrow R1, and the Z-axis feeding means 60 is operated to lower the cutting means 20 for cutting. While supplying the processing water from the processing water supply unit 24 of the means 20, the cutting feed is performed at a depth corresponding to the finished thickness, the X-axis feeding means 40 is operated, and the chuck table 34 is processed and fed in the direction indicated by the arrow X1. Then, a cutting groove is formed along the planned division line 14. Further, the Y-axis feed means 50 is operated, and the cutting blade 21 of the cutting means 20 is adjacent to the scheduled division line 14 in which the cutting groove is formed in the Y-axis direction and is on the scheduled division line 14 in which the cutting groove is not formed. Is indexed and fed to form a cutting groove in the same manner as above. By repeating these steps, a cutting groove is formed along all the planned division lines 14 along the X-axis direction. Next, the chuck table 34 was rotated 90 degrees, the direction orthogonal to the direction in which the cutting groove was formed earlier was aligned in the X-axis direction, and the above-mentioned machining for forming the cutting groove was newly aligned in the X-axis direction. It is carried out for the scheduled division line 14 of the above, and the cutting process for forming a cutting groove along all the scheduled division lines 14 formed on the wafer 10 is carried out.

During the above-mentioned cutting process, clean water L is constantly supplied from the water supply unit 36d of the frame body 36, and a clean water seal S is formed along the outer circumference 10c of the wafer 10. To. Therefore, the waste liquid mixed with the cutting chips generated when the cutting groove is formed is suppressed from entering through the gap between the outer peripheral surface 10c of the wafer 10 and the outer peripheral surface of the chuck table 34, and the back surface 10b side of the wafer 10 is prevented from entering. And the suction surface 35A of the porous plate 35 is suppressed from being contaminated.

According to the chuck table 34 of the present embodiment, since the central region 35a of the porous plate 35 is formed by the coarse porous, the negative pressure Vm1 efficiently acts on the suction surface 35A side, and the central side of the wafer 10 A wide range of can be sucked with a strong negative pressure, and suction and holding during cutting can be ensured. Further, since the outer peripheral region 35c of the porous plate 35 is formed of a fine porous, the chuck table 34 sucks and holds the outer peripheral 10c side of the wafer 10 on the suction surface 35A with an appropriately lowered negative pressure Vm2. It suppresses the suction of waste liquid from the outer peripheral side of the wafer 10 to the lower surface side of the wafer 10.

As described above, according to the chuck table 34 and the cutting device 1 of the present embodiment, while the wafer 10 is reliably sucked and held on the chuck table 34, waste liquid is suppressed from entering the outer peripheral side of the chuck table 34. This prevents the porous plate 35 from being contaminated. However, when the cutting process for the wafer 10 is completed and the wafer 10 is taken out from the chuck table 34, the porous plate 35 may be exposed and the chuck table 34 may be contaminated, so the chuck table 34 should be cleaned regularly. Is preferable.

Therefore, in the present embodiment described above, as shown in FIG. 6, the water supply source 73 is connected to the second negative pressure supply path 36k via the second water supply path 36n provided with the fourth valve 37d. These configurations function as cleaning means for cleaning the outer peripheral region 35c of the porous plate 35. The operation of the cleaning means will be described with reference to FIG.

When cleaning the outer peripheral region 35c of the porous plate 35, first, the first negative pressure supply source 71 and the second negative pressure supply source 72 are stopped, and the first valve 37a and the second valve 37b are closed. Next, the fourth valve 37d is opened to operate the water supply source 73. As a result, the water L supplied from the water supply source 73 is supplied from the back surface side to the outer peripheral region 35c of the porous plate 35 via a part of the second water supply passage 36n and the second negative pressure supply passage 36k. .. As a result, even if the contaminant is adsorbed on the outer peripheral region 35c of the porous plate 35, the contaminant is discharged from the surface of the outer peripheral region 35c, that is, the suction surface 35A side together with the backflowing water L, and the porous plate 35 is discharged. The outer peripheral region 35c is cleaned. At this time, as shown in FIG. 6, the third valve 37c is also opened at the same time, water L is supplied from the water supply source 73 to the first water supply path 36m, and the outer peripheral region 35c of the porous plate 35 is supplied together with the third valve 37c. (1) The water supply path 36m and the water supply section 36d may be cleaned. Further, when carrying out the cleaning, it is preferable to operate a rotation driving means (not shown) for rotating the chuck table 34 to rotate the chuck table 34. As a result, the water L after cleaning the outer peripheral region 35c of the porous plate 35 does not flow to the central region 35a side, and it is avoided that the water L after cleaning is contaminated.

Further, according to the chuck table 34 of the present embodiment, the outer peripheral 10c side of the wafer 10 is water-sealed by the water seal S, so that air does not enter from the outer peripheral 10c side, the holding force for holding the wafer 10 is increased, and the wafer is held. Since the outer peripheral 10c side of the 10 is also reliably sucked and held and does not flutter, it is possible to uniformly form the depth of the cutting groove also on the outer peripheral 10c side of the wafer 10.

In the above-described embodiment, an example in which the chuck table 34 configured based on the present invention is applied to the cutting device 1 is shown, but the present invention is not limited to this, and the chuck table holds the wafer in the grinding device. It can also be applied. Even in that case, as described above, the waste liquid mixed with the grinding debris generated by grinding the back surface of the wafer is suppressed from entering from the outer peripheral side of the chuck table, and the chuck table may be contaminated. Be avoided.

Further, in the above-described embodiment, the water L is supplied to the outer peripheral region 35c of the porous plate 35, but the present invention is not limited to this, and the water L is also supplied to the central region 35a of the porous plate 35. The water supply channel to be supplied may be formed. With this configuration, after the cutting of the wafer 10 is completed, water L is supplied from the central region 35a of the porous plate 35 and the back surface side of the outer peripheral region 35c and ejected to the suction surface 35A side of the porous plate 35. By floating the processed wafer 10 from the chuck table 34, the wafer 10 can be carried out without being damaged.

Further, in the above-described embodiment, the coarseness of the mesh between the central region 35a and the outer peripheral region 35c of the porous plate 35 is set to be different, but the present invention is not limited to this, and the central region 35a and the outer peripheral region 35c are not limited to this. And may be set to the same roughness.

1: Cutting device 1A: Base 1B: Valve frame 10: Waha 10a: Front surface 10b: Back surface 10c: Outer circumference 20: Cutting means 20A: Spindle housing 21: Cutting blade 22: Spindle 23: Blade cover 24: Processing water supply unit 28: Imaging means 30: Holding means 31: X-axis direction movable plate 32: Cylindrical member 33: Cover member 34: Chuck table 35: Porous plate 35A: Suction surface 35a: Central region 35b: Bulb 35c: Outer peripheral region 36: Frame 36a: Recessed portion 36b: Outer peripheral wall portion 36c: Bottom portion 36d: Water supply portion 36e: Water supply hole 36f: Central negative pressure supply hole 36g: Central groove portion 36h: Outer peripheral negative pressure supply hole 36i: Outer peripheral groove portion 36j: First negative pressure supply Path 36k: Second negative pressure supply path 36m: First water supply path 36n: Second water supply path 37a: First valve 37b: Second valve 37c: Third valve 37d: Fourth valve 40: X-axis feeding means 50 : Y-axis feeding means 60: Z-axis feeding means 71: First negative pressure supply source 72: Second negative pressure supply source 73: Water supply source 100: Control means S: Water seal L: Water

Claims (4)

A cutting device provided with at least a chuck table for holding a wafer and a cutting means for performing cutting while supplying machining water to the wafer held on the chuck table.
The chuck table includes a porous plate having a suction surface for sucking and holding a wafer, and a frame body that exposes the suction surface and surrounds the porous plate.
The porous plate includes a central region that sucks and holds the central side of the wafer and an outer peripheral region that surrounds the central region via a partition wall.
A cutting device in which an annular water supply portion is formed in the frame body to supply water to the outer periphery of a wafer sucked and held by the suction surface to form a water seal. The frame is provided with an outer peripheral suction path that supplies a suction negative pressure to the suction surface of the outer peripheral region of the porous plate, and water is supplied from a water supply source to the outer peripheral region of the porous plate via the outer peripheral suction path. The cutting device according to claim 1, further comprising a cleaning means for cleaning the outer peripheral region. A porous plate having a suction surface for sucking and holding the wafer, and a frame body for exposing the suction surface and surrounding the porous plate are provided.
The porous plate comprises a central region that suctions and holds the central side of the wafer and an outer peripheral region that surrounds the central region via a partition wall.
A chuck table having an annular water supply portion formed on the frame body by supplying water to the outer periphery of a wafer sucked and held by the suction surface to form a water seal. The frame body is provided with an outer peripheral suction path that supplies a suction negative pressure to the suction surface of the outer peripheral region of the porous plate, and the outer peripheral suction path is provided in the outer peripheral region of the porous plate via the outer peripheral suction path. The chuck table according to claim 3, wherein a water supply path for supplying water is connected.

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