JP2023014896A - holding table - Google Patents

Abstract

To wash an upper surface of a support plate around a holding table by utilizing cooling water.SOLUTION: A holding table 6 includes: a holding portion 610 for holding a workpiece; a frame body 620 having a recessed portion 621 for accommodating the holding portion 610, and surrounding the holding portion 610; a cooling unit 630 that cools the holding table 6; and a cover 640 surrounding the frame body 620. The cooling unit 630 has: a water channel 631 communicating with a water source, formed inside the frame body 620, and supplying cooling water to the inner part of the frame body 620; and a discharge port 633 formed in one end of the water channel 631 and opening in a side wall 642 of the frame body 620. A cover 640 has the side wall 642 suspended at an angle in an outwardly spreading direction. A predetermined empty space 700 is formed between a lower end of the side wall 642 and a support plate. Cooling water discharged from the discharge port 633 collides with the cover 640, flows along the side wall 642, is supplied to an upper surface 510 of the support plate, and washes the upper surface 510 of the support plate.SELECTED DRAWING: Figure 2

Description

The present invention relates to holding tables.

A polishing apparatus for mirror-finishing the surface of a plate-like work, which is an object to be processed, comprises at least a chuck table for sucking and holding the plate-like work, and polishing means having a polishing pad for polishing the plate-like work. A pad is used to polish the surface of the plate-like work. For example, Japanese Unexamined Patent Application Publication No. 2002-100001 discloses a chuck table having a water channel for cooling supplied to the inside of a frame body of a holding table.

Japanese Unexamined Patent Application Publication No. 2014-237200

In a conventional processing apparatus, when a cleaning unit for cleaning the holding surface of the holding table is provided, a separate cleaning unit for cleaning the upper surface of the support plate that supports the holding table is not provided. Therefore, in the conventional processing apparatus, when the upper surface of the support plate becomes dirty, there is a need to clean the upper surface of the support plate.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a holding table that can wash the upper surface of a support plate around the holding table using cooling water.

In order to solve the above-described problems and achieve the object, the holding table of the present invention is a holding table that is installed on a support plate and holds a workpiece, and has a holding part that holds the workpiece. a frame surrounding the holding part and having a recess for accommodating the holding part; a cooling unit cooling the holding table; and a cover surrounding the frame, the cooling unit comprising: a water channel that communicates with a water source and is formed inside the frame to supply cooling water to the inside of the frame; The cover has a side wall that slopes downward in an outwardly widening direction, and a predetermined gap is formed between the lower end of the side wall and the support plate, and the cooling discharged from the discharge port is provided. Water impinges on the inner wall of the cover and flows along the side walls and is supplied to the upper surface of the support plate to wash the upper surface of the support plate.

In the holding table, the support plate may be a turntable that rotatably supports one or more holding tables.

The processing apparatus of the present invention has the effect of being able to wash the upper surface of the support plate around the holding table using cooling water.

FIG. 1 is a perspective view showing a configuration example of a processing apparatus provided with a holding table according to an embodiment. FIG. 2 is a schematic cross-sectional view showing a configuration example of the holding table shown in FIG. 3 is an exploded perspective view of the holding table shown in FIG. 1. FIG. FIG. 4 is an exploded perspective view showing the holding table shown in FIG. 1 from below. FIG. 5 is a schematic cross-sectional view showing a configuration example of a holding table according to a modification of the embodiment. FIG. 6 is an exploded perspective view of a holding table according to a modification of the embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. In addition, the components described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. In addition, various omissions, substitutions, or changes in configuration can be made without departing from the gist of the present invention. In each of the following embodiments, the same parts are denoted by the same reference numerals, and overlapping descriptions are omitted.

In the embodiments described below, an XYZ orthogonal coordinate system is set, and the positional relationship of each part will be described with reference to this XYZ orthogonal coordinate system. One direction in the horizontal plane is the X-axis direction, the direction perpendicular to the X-axis direction in the horizontal plane is the Y-axis direction, and the direction perpendicular to the X-axis direction and the Y-axis direction is the Z-axis direction. An XY plane containing the X and Y axes is parallel to the horizontal plane. The Z-axis direction perpendicular to the XY plane is the vertical direction.

[Embodiment]
A processing apparatus 1 according to an embodiment of the present invention will be described based on the drawings. FIG. 1 is a perspective view showing a configuration example of a processing apparatus 1 having a holding table according to an embodiment.

In FIG. 1, the processing apparatus 1 according to the embodiment can grind a region corresponding to the device region on the back surface of the workpiece 200 (work) to form the device region with a predetermined thickness.

In FIG. 1, a workpiece 200, which is an object to be ground by the machining apparatus 1, has a base material 201, for example. The base material 201 is, for example, disk-shaped silicon, and is a wafer such as a disk-shaped semiconductor wafer or an optical device wafer. A device may be formed in a region partitioned by a plurality of planned division lines formed in a grid pattern on one of the surfaces. The workpiece 200 has an adhesive tape 205 attached to one surface. Workpiece 200 includes, for example, a substrate.

The processing apparatus 1 includes, for example, a housing 2, a first processing means 3, a second processing means 4, three holding tables 6 installed on a turntable 5, cassettes 7 and 8, and a position Aligning means 9 , carrying-in means 10 , carrying-out means 11 , cleaning means 12 , and carrying-in/out means 13 are provided. In this embodiment, the processing apparatus 1 is described as having two processing means, but the number of processing means is not limited to this. For example, the processing device 1 may have three or more processing means. The operation of the processing apparatus 1 is controlled by a control unit or the like (not shown). In this embodiment, the turntable 5 is an example of a support plate.

The turntable 5 is a disk-shaped one provided on the upper surface of the housing 2, is provided rotatably in a horizontal plane, and is rotationally driven at appropriate timing. For example, three holding tables 6 are arranged on the turntable 5 at equal intervals with a phase angle of 120 degrees, for example. These holding tables 6 have a chuck table structure with a vacuum chuck on the upper surface, and hold the workpiece 200 placed on the flat holding surface by vacuum adsorption. During grinding, these holding tables 6 are rotated in a horizontal plane about a rotation axis perpendicular to the holding surface by a rotation drive mechanism (not shown). By rotating the turntable 5, the holding table 6 can move between a loading/unloading position 101, a rough grinding position 102 facing the first processing means 3, and a finish grinding position 103 facing the second processing means 4. is relatively moved.

The first processing means 3 includes a first grinding wheel 3-1 having a first grinding surface facing the holding surface of the holding table 6 positioned at the rough grinding position B, and the first grinding wheel 3-1. a first spindle portion 3-2 rotatably supporting a vertical axis perpendicular to the first grinding surface as a first rotation axis; and a first slide portion 3-3 that is supported so as to be able to move back and forth in the axial direction. Here, as the first grinding wheel 3-1, one for rough grinding with coarse abrasive grains is used. That is, the first grinding wheel 3-1 having the first grinding surface detachably attached to the lower end of the first spindle part 3-2 is rotated around the first rotating shaft by the motor 3-4. Meanwhile, the upper surface of the workpiece 200 is pressed and brought into contact with the upper surface of the workpiece 200 held on the holding surface of the holding table 6 positioned at the rough grinding position 102 by the first slide portion 3-3. It is for performing a predetermined rough grinding process.

The second processing means 4 includes a second grinding wheel 4-1 having a second grinding surface facing the holding surface of the holding table 6 positioned at the finish grinding position C, and the second grinding wheel 4-1. a second spindle portion 4-2 rotatably supporting a vertical axis perpendicular to the second grinding surface as a second rotation axis; and a second slide portion 4-3 that supports the second slide portion 4-3 so as to be able to move back and forth in the axial direction of the second slide portion 4-3. Here, as the second grinding wheel, a wheel for finish grinding with fine abrasive grains is used. That is, the second grinding wheel 4-1 having the second grinding surface detachably attached to the lower end of the second spindle part 4-2 is rotated around the second rotating shaft by the motor 4-4. Meanwhile, the upper surface of the workpiece 200 is pressed and brought into contact with the upper surface of the workpiece 200 held on the holding surface of the holding table 6 positioned at the finish grinding position C by the second slide portion 4-3. It is for performing a predetermined finish grinding process. Like the first processing means 3, the second processing means 4 has a mechanism for tilting the second rotation axis with respect to the rotation axis, although not shown.

Further, the first slide portion 3-3 and the second slide portion 4-3 of the first processing means 3 and the second processing means 4 are provided so as to be vertically fed by the vertically feeding means 15 and 16, respectively. The first grinding wheel 3-1 and the second grinding wheel 4-1 are configured to be capable of being fed to the upper surface of the workpiece 200 on the holding table 6 for grinding. These lifting means 15 and 16 are mounted on movable blocks 17 and 18 provided on the upper surface of the housing 2 . The movable blocks 17 and 18 are arranged in the radial direction of the turntable 5 with respect to the holding table 6 where the first grinding wheel 3-1 and the second grinding wheel 4-1 are positioned at the rough grinding position 102 and the finish grinding position 103. It is movably provided with respect to the housing 2 by a moving mechanism (not shown) so as to move forward and backward.

Cassettes 7, 8 are receptacles for workpieces 200 having a plurality of slots. One cassette 7 accommodates a workpiece 200 before grinding, and the other cassette 8 accommodates a workpiece 200 after grinding. The workpiece 200 is not particularly limited, but may be, for example, a silicon wafer, a semiconductor wafer such as GaAs, ceramic, glass, a sapphire (Al ₂ O ₃ )-based inorganic material substrate, a plate metal or a ductile material such as resin, Furthermore, the in-plane flatness from the micron order to the submicron order (TTV: Total Thickness Variation: the maximum value of the height measured in the thickness direction with the ground surface of the workpiece 200 as a reference plane over the entire surface of the workpiece 200 and the minimum value) are required for various processing materials.

Further, the positioning means 9 is a table on which the workpiece 200 taken out from the cassette 7 is temporarily placed and for performing center positioning. The carrying-in means 10 is composed of a carrying-in arm that has a suction pad and is rotationally driven in a horizontal plane. It is carried in on the holding table 6 which is located. The carry-out means 11 includes a carry-in arm that has a suction pad and is rotationally driven in a horizontal plane, and sucks and holds the workpiece 200 after grinding held on the holding table 6 positioned at the carry-in/carry-out position 101 . to the cleaning means 12. Further, the loading/unloading means 13 is, for example, a robot pick having a U-shaped hand, and carries in the workpiece 200 while sucking and holding the workpiece 200 with the U-shaped hand. Specifically, the loading/unloading means 13 carries out the unground workpiece 200 from the cassette 7 to the alignment means 9 and carries the ground workpiece 200 from the cleaning means 12 to the cassette 8 . . The cleaning means 12 cleans the workpiece 200 after grinding, and removes contamination such as grinding waste adhering to the ground surface.

(Configuration example of holding table)
An example of the holding table 6 according to the embodiment will be described. FIG. 2 is a schematic cross-sectional view showing a configuration example of the holding table 6 shown in FIG. 3 is an exploded perspective view of the holding table 6 shown in FIG. 1. FIG. FIG. 4 is an exploded perspective view showing the holding table 6 shown in FIG. 1 from below. The plurality of holding tables 6 shown in FIG. 1 have the same basic configuration. In the example shown in FIG. 2, one holding table 6 out of the plurality of holding tables 6 is shown.

As shown in FIG. 2, the holding table 6 is provided on the turntable 5 (support plate) and is configured to hold the workpiece 200, which is a substrate. The holding table 6 is provided so as to protrude from the upper surface 510 of the turntable 5 to the outside of the processing apparatus 1 . The holding table 6 has a holding portion 610 that holds the workpiece 200 and a recessed portion 621 that accommodates the holding portion 610 , a frame 620 that surrounds the holding portion 610 , and a cooling unit 630 that cools the holding table 6 . and a cover 640 surrounding the frame 620 .

As shown in FIGS. 2 and 3, the holding portion 610 is a disk-shaped suction plate. The holding part 610 is composed of, for example, a porous holding member or the like, and its upper surface serves as a holding surface 611 for holding the workpiece by suction. The holding part 610 contacts the lower surface of the workpiece 200 and holds the workpiece 200 with the upper surface of the workpiece 20 exposed.

The frame 620 is formed with a recess 621 having an inner diameter larger than the outer diameter of the holding portion 610 at the central portion of the frame 620 . A suction path 605 is provided in the center of the recess 621 to connect the holding portion 610 and the suction source 650 . The holding table 6 can be used by fitting the holding portion 610 into the concave portion 621 of the frame 620 . A rotating shaft 622 to which a rotating unit 660 is connected is connected to the frame 620 . The rotating unit 660 is composed of a pulley 662 connected to a motor 661 , a pulley 663 attached to a rotating shaft 622 , and a belt 664 wound around the pulleys 662 and 663 . The rotation unit 660 can rotate the frame 620 together with the rotating shaft 622 by driving the pulley 662 so that the belt 664 follows the pulley 663 .

The cooling unit 630 includes a water channel 631 that is formed inside the frame 620 and supplies cooling water to the inside of the frame 620 , and a plurality of exhaust pipes that are formed at one end of the water channel 631 and open to a side wall 623 of the frame 620 . an outlet 633; In this embodiment, the case where there are four outlets 633 is described, but the number of outlets 633 may be other than four.

In the example shown in FIG. 4 , the cooling unit 630 has at least four water channels 631 radially extending from the center of the frame 620 and not communicating with the suction channel 605 . The number of water channels 631 is not limited to four. Water channel 631 extends parallel to holding portion 610 shown in FIG. A supply port 632 that connects the water channel 631 and a water source 634 is formed at the other end of the water channel 631 .

The plurality of outlets 633 are formed at positions obtained by equally dividing the outer circumference of the side wall 623 of the frame 620 into four, but they may not be equally spaced. A discharge port 633 is formed as an opening in the side wall 623 at the end of the channel 631 . The outlet 633 is an opening through which the cooling water from the water channel 631 can be discharged toward the cover 640 outside the frame 620 .

Returning to FIG. 2 , in the cooling unit 630 , when the water source 634 is activated, cooling water flows into the supply port 632 and flows through the water channel 631 , thereby cooling the frame 620 and contacting the frame 620 . The holding part 610 which is holding can also be cooled. The cooling unit 630 discharges the cooling water in the water channel 631 from the discharge port 633 .

The cover 640 is formed to prevent processing waste from adhering to the frame 620 and the rotating unit 660 . The cover 640 has a base portion 641 that surrounds the frame 620 and side walls 642 that extend downward from the base portion 641 while being inclined. The direction of spreading outward from the base 641 includes, for example, the direction of spreading away from the frame 620 . The cover 640 is a tapered member in which a base portion 641 and side walls 642 are integrally formed, for example, from a metal member, synthetic resin, or the like. The cover 640 is a member that rotatably exposes the concave portion 621 of the frame 620 and covers other portions of the frame 620 .

The base portion 641 is formed in a flat plate ring shape having an inner diameter larger than the outer diameter of the frame 620 . The base 641 is positioned and fixed so as to have a gap with respect to the rotating frame 620 . The side wall 642 is formed to be an inclined surface extending outward from the outer periphery of the base 641 toward the upper surface 510 of the turntable 5 . Side wall 642 forms a predetermined gap 700 between frame 620 and upper surface 510 of turntable 5 . Gap 700 includes the space inside sidewall 642 . Gap 700 includes a space through which cooling water is discharged from outlet 633 of cooling unit 630 . A fixing portion 643 parallel to the upper surface 510 of the turntable 5 is formed at the end of the side wall 642 .

The fixed portion 643 is fixed to the top surface 510 of the turntable 5 by a fixing member 644 . The fixing part 643 is fixed at a position separated from the upper surface 510 of the turntable 5 by the height of the fixing member 644, thereby forming a gap 700 between the fixing part 643 and the upper surface 510 of the turntable 5. there is That is, the gap 700 is a space that allows cooling water discharged from the outlet 633 of the cooling unit 630 to be discharged to the upper surface 510 of the turntable 5 outside the cover 640 . In this embodiment, the fixing member 644 is fixed by fixing the fixing portion 643 to the upper surface 510 of the turntable 5 at three or more different points in the circumferential direction of the fixing portion 643 of the cover 640 .

(Example of action of holding table)
As shown in FIG. 2, the cooling water 800 supplied from the water source 634 to the water channel 631 cools the frame 620 and moves toward the discharge port 633 by the operation of the water source 634 . The cooling water 800 discharged from the discharge port 633 of the holding table 6 collides with the inner wall of the cover 640 , flows along the side wall 642 , and is supplied to the upper surface 510 of the turntable 5 . Wash 510; As a result, when the cooling water 800 collides with the upper surface 510 of the turntable 5 , the holding table 6 is supplied in a direction 810 away from the holding table 6 , thereby cleaning the upper surface 510 of the turntable 5 around the holding table 6 . can do. The away direction 810 is the direction away from the holding table 6 . The holding table 6 discharges the cooling water 800 while the frame 620 is being rotated, thereby increasing the force of the collision against the inner wall of the cover 640 by centrifugal force and supplying the cooling water 800 to the entire circumference of the holding table 6. can do. The holding table 6 discharges the cooling water 800 while the rotation of the frame 620 is stopped, so that the cooling water 800 can be intensively supplied to a desired portion around the holding table 6 .

As described above, the holding table 6 forms the cover 640 against which the cooling water 800 supplied to the inside of the frame 620 surrounding the holding portion 610 collides, and the side wall 642 of the cover 640 is inclined so as to expand outward. there is As a result, the holding table 6 allows the cooling water 800 that collides with the inner surface (inner wall) of the side wall 642 of the cover 640 to flow along the inclination of the side wall 642 and move the upper surface 510 of the turntable 5 positioned outside the holding table 6. can be washed. Since the top surface 510 of the turntable 5 inside the cover 640 is covered with the cover 640 , it is less likely to get dirty than the top surface 510 of the turntable 5 outside the cover 640 . If the side wall 642 were not inclined, the cooling water would fall into the cover 640 and only wash the upper surface 510 of the turntable 5 inside the cover 640 . According to the present invention, the side wall 642 of the cover 640 of the holding table 6 is slanted, so that the upper surface 510 of the turntable 5 outside the cover 640, on which processing waste tends to accumulate, can be efficiently cleaned.

For example, if the holding table 6 discharges the cooling water 800 directly to the turntable 5 without using the cover 640, the water may scatter before reaching the upper surface of the turntable 5, making it impossible to wash the target area. However, in the present invention, the cooling water 800 is efficiently supplied to the turntable 5 without splashing into the machining space by causing the holding table 6 to collide with the cover 640 and flow the cooling water 800 along the side wall 642 . can be done.

For example, the top surface 510 of the turntable 5 of the processing apparatus 1 may be dirty or dust may be present. Since the holding table 6 according to the embodiment can effectively use the cooling water 800 for cooling the inside of the frame 620 to clean the upper surface 510 of the turntable 5 around the holding table 6, the turntable 5 can be Cleaning work can be simplified.

Since the processing apparatus 1 includes the holding table 6 according to the embodiment, it is not necessary to separately include a cleaning unit for cleaning the turntable 5 . Thereby, the processing apparatus 1 can wash the upper surface 510 of the turntable 5 by the holding table 6 without using a dedicated washing unit.

Although the holding table 6 includes the rotation unit 660 in the embodiment, the present invention is not limited to this. For example, when the holding table 6 is rotated by external power, or when the holding table 6 is not rotated, the rotation unit 660 may be omitted from the configuration.

In the embodiment, the case where the support plate of the holding table 6 is the turntable 5 has been described, but the present invention is not limited to this. For example, the support plate includes the housing of the processing device 1 that supports the holding table 6, and the like.

[Modification of Embodiment]
The holding table 6 according to the embodiment described above can be modified as follows. For example, when the holding table 6 is configured such that the cover 640 covers a wide range of the upper surface 510 of the turntable 5, the distance between the frame 620 and the cover 640 may increase. For this reason, the holding table 6 may have a configuration in which the discharge port 633 protrudes when the cleaning effect is not sufficient due to the distance between the frame 620 and the cover 640 .

FIG. 5 is a schematic cross-sectional view showing a configuration example of a holding table 6 according to a modification of the embodiment. FIG. 6 is an exploded perspective view of a holding table 6 according to a modification of the embodiment. As shown in FIG. 5 , the holding table 6 includes a holding portion 610 , a frame body 620 , a cooling unit 630 and a cover 640 . As shown in FIGS. 5 and 6, the cooling unit 630 includes a water channel 631 and a plurality of outlets 633 - 1 formed at one end of the water channel 631 and opening to the sidewall 623 of the frame 620 .

The outlet 633-1 is formed to protrude from the side wall 623 of the frame 620 to the outside. The discharge port 633 - 1 communicates with the water channel 631 and has a tubular shape extending from the side wall 623 of the frame 620 to the vicinity of the inner wall of the cover 640 . The length of the outlet 633-1 can be arbitrarily designed according to, for example, the distance from the end of the outlet 633-1 to the inner wall of the cover 640, the discharge amount of cooling water, and the like. Although the discharge port 633-1 is provided perpendicular to the side wall 623 of the frame 620, it may be inclined with respect to the side wall 423. FIG.

The holding table 6 is configured such that the discharge port 633 - 1 protrudes from the frame 620 , so that the cooling water 800 can be vigorously collided with the inner wall of the cover 640 . Since the holding table 6 protrudes the discharge port 633-1, the cooling water 800 does not scatter and lose its momentum. can be improved.

Although the holding table 6 according to the embodiment has been described as being used in the processing device 1 for grinding, the processing device 1 is not limited to the above-described embodiment, and can be variously modified without departing from the gist of the present invention. can be implemented. For example, the processing device 1 may be a cutting device or a laser processing device other than a grinding device.

1 Processing Device 3 First Processing Means 4 Second Processing Means 5 Turntable 6 Holding Table 7 Cassette 8 Cassette 9 Alignment Means 10 Loading Means 11 Carrying Out Means 12 Washing Means 13 Carrying In/Out Means 510 Upper Surface 610 Holding Part 620 Frame 621 recess 622 rotary shaft 623 side wall 630 cooling unit 631 water channel 632 supply port 633 outlet 633-1 outlet 634 water source 640 cover 641 base 642 side wall 643 fixing part 644 fixing member 650 suction source 660 rotating unit 661 motor 662 pulley 663 Belt 700 Gap 800 Cooling water

Claims (2)

A holding table mounted on the support plate and holding the workpiece,
a holding part that holds the workpiece;
a frame that has a recessed portion that houses the holding portion and that surrounds the holding portion;
a cooling unit for cooling the holding table;
a cover surrounding the frame,
The cooling unit is
a water channel communicating with a water source and formed inside the frame for supplying cooling water to the inside of the frame;
a discharge port formed at one end of the water channel and opening to a side wall of the frame;
The cover is
having an outwardly sloping depending sidewall,
A predetermined gap is formed between the lower end of the side wall and the support plate,
the cooling water discharged from the outlet collides with the inner wall of the cover and flows along the side wall;
A holding table that is supplied to the upper surface of the support plate to clean the upper surface of the support plate. The support plate is
2. The holding table according to claim 1, which is a turntable that rotatably supports one or more holding tables.

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