JP2012121088A - Chuck table mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chuck table mechanism having a function for cooling a chuck table.SOLUTION: This chuck table mechanism 5 includes a chuck table 6, and a cooling medium supply means 7. The chuck table 6 includes a holding table 61, and a support member 62. The support member 62 is provided with a first communication path 633 communicating with one end of a cooling medium flow path 622 for flowing a cooling medium, and a second communication path 634 communicating with the other end. The cooling medium supply means 7 includes a cooling medium cooling means 71, a pump 72 for supplying the cooling medium, a cooling medium supply pipe 73, a cooling medium return pipe 74, and a switching valve 75 which can be switched between a first mode in which the cooling medium supply pipe 73 communicates with the first communication path 633 and the second communication path 634 communicates with the cooling medium return pipe 74, and a second mode in which the cooling medium supply pipe 73 communicates with the second communication path 634 and the first communication path 633 communicates with the cooling medium return pipe 74.

Description

  The present invention is provided with a chuck table mechanism equipped with a chuck table that holds a workpiece, and more specifically, has a function of cooling the chuck table. The chuck table mechanism is provided in a processing apparatus such as a polishing apparatus that polishes a workpiece such as a semiconductor wafer. The present invention relates to a chuck table mechanism.

  In the semiconductor device manufacturing process, a plurality of regions are partitioned by dividing lines called streets arranged in a lattice pattern on the surface of a substantially wafer-shaped semiconductor wafer, and devices such as ICs, LSIs, etc. are partitioned in these partitioned regions. Form. By dividing the semiconductor wafer on which a plurality of devices are formed in this way along the streets, individual devices are formed. In order to reduce the size and weight of a device, the semiconductor wafer is usually ground to the predetermined thickness by grinding the backside of the semiconductor wafer prior to cutting the semiconductor wafer along the street and dividing it into individual devices. ing. The grinding of the back surface of a semiconductor wafer is usually performed by pressing a grinding wheel formed by fixing diamond abrasive grains with an appropriate bond such as a resin bond against the back surface of the semiconductor wafer while rotating at high speed. When the back surface of the semiconductor wafer is ground by such a grinding method, a so-called processing strain is generated on the back surface of the semiconductor wafer, which causes a problem that the bending strength of the individually divided devices is lowered.

  In order to solve the above-described problem, a polishing apparatus that removes grinding distortion by dry-polishing the back surface of a ground semiconductor wafer with a polishing pad mixed with abrasive grains is disclosed in Patent Document 1 below.

JP 2003-243345 A

  Thus, when the back surface of the wafer is dry-polished, frictional heat is generated, and this frictional heat causes a problem that the quality of the device is degraded.

  The present invention has been made in view of the above facts, and the main technical problem thereof is a function of cooling a chuck table that holds a workpiece that can be processed while effectively cooling the workpiece such as a wafer. It is in providing a chuck table mechanism provided with.

In order to solve the main technical problem, according to the present invention, in a chuck table mechanism comprising a chuck table for holding a workpiece and a cooling medium supply means for supplying a cooling medium for cooling the chuck table. ,
The chuck table includes a holding table having a holding surface that holds a workpiece, and a support member that supports the holding table, and a cooling medium that flows a cooling medium for cooling the holding table to the support member. A first communication path that communicates with one end of the flow path and a second communication path that communicates with the other end of the cooling medium flow path;
The cooling medium supply means includes a cooling medium cooling means for cooling the cooling medium, a pump for feeding the cooling medium cooled by the cooling medium cooling means, and a cooling medium for sending the cooling medium fed by the pump The cooling medium return pipe that returns the cooling medium that has cooled the holding table of the chuck table to the cooling medium cooling means, the cooling medium supply pipe, and the first communication path communicate with the second pipe. The first communication path and the cooling medium return pipe, the cooling medium delivery pipe and the second communication path, and the first communication path and the cooling medium return pipe. A switching valve that can be switched to the second form that communicates,
A chuck table mechanism is provided.

  The chuck table mechanism according to the present invention includes a first communication path that communicates with one end of a cooling medium flow path through which a cooling medium for cooling the holding table flows to the support member that constitutes the chuck table that holds the workpiece. A second communication path that communicates with the other end of the medium flow path, and a cooling medium supply means that supplies a cooling medium for cooling the chuck table delivers the cooling medium cooling means and the cooling medium. A cooling medium delivery pipe for delivering a cooling medium delivered by the pump; a cooling medium return pipe for returning the cooling medium that has cooled the chuck table to the cooling medium cooling means; a cooling medium delivery pipe; The first communication path and the second communication path and the cooling medium return pipe, the cooling medium delivery pipe and the second communication path, and the first communication path and the cooling. Since the switching valve that can be switched to the second form communicating with the body return pipe is provided, the cooling medium flow passage is changed by alternately switching the switching valve to the first form and the second form. The flow direction of the flowing cooling medium is alternately changed. Therefore, the workpiece holding area of the holding table can be uniformly and effectively cooled.

The perspective view which shows one Embodiment of the grinding | polishing apparatus equipped with the chuck table mechanism comprised by this invention. The perspective view which shows the grinding | polishing tool which comprises the grinding | polishing unit with which the grinding | polishing apparatus shown in FIG. 1 is equipped. The perspective view which shows the state which looked at the polishing tool shown in FIG. 2 from the lower surface side. The perspective view which shows the chuck table mechanism and chuck table moving mechanism with which the grinding | polishing apparatus shown in FIG. 1 is equipped. Explanatory drawing which fractures | ruptures and shows the principal part of the chuck table which comprises the chuck table mechanism shown in FIG. 4, and a cooling medium supply means. FIG. 6 is a cross-sectional view taken along line AA in FIG. 5. Explanatory drawing of the grinding | polishing process implemented with the grinding | polishing apparatus shown in FIG.

  Hereinafter, a preferred embodiment of a chuck table mechanism configured according to the present invention will be described in more detail with reference to the accompanying drawings.

FIG. 1 is a perspective view of a polishing apparatus equipped with a chuck table mechanism constructed according to the present invention.
A polishing apparatus 1 shown in FIG. 1 includes an apparatus housing denoted as a whole by numeral 2. The apparatus housing 2 has a rectangular parallelepiped main portion 21 that extends elongated, and an upright wall 22 that is provided at the rear end portion (upper right end in FIG. 1) of the main portion 21 and is disposed in the vertical direction. Yes. A pair of guide rails 221 and 221 extending in the vertical direction are provided on the front surface of the upright wall 22. The pair of guide rails 221 and 221 is mounted with a polishing unit 3 as a polishing means so as to be movable in the vertical direction.

  The polishing unit 3 includes a moving base 31 and a spindle unit 32 attached to the moving base 31. The movable base 31 is provided with a pair of legs 311 and 311 extending in the vertical direction on both sides of the rear surface. The pair of legs 311 and 311 is slidably engaged with the pair of guide rails 221 and 221. Guided grooves 312 and 312 are formed. As described above, a support portion 313 protruding forward is provided on the front surface of the movable base 31 slidably mounted on the pair of guide rails 221 and 221 provided on the upright wall 22. The spindle unit 32 is attached to the support portion 313.

  The spindle unit 32 includes a spindle housing 321 mounted on the support portion 313, a rotating spindle 322 rotatably disposed on the spindle housing 321, and a servo as rotation driving means for driving the rotating spindle 322 to rotate. And a motor 323. The lower end of the rotary spindle 322 protrudes downward beyond the lower end of the spindle housing 321, and a disk-shaped tool mounting member 324 is provided at the lower end. The tool mounting member 324 is formed with a plurality of bolt insertion holes (not shown) at intervals in the circumferential direction. A polishing tool 325 is mounted on the lower surface of the tool mounting member 324. As shown in FIGS. 2 and 3, the polishing tool 325 includes a circular support base 326 and a circular polishing pad 327. The support base 326 is formed of an aluminum alloy, and has a plurality of blind screw holes 326a extending downward from the upper surface thereof at intervals in the circumferential direction. The lower surface of the support base 326 forms a circular support surface, and a polishing pad 327 is attached with a double-sided adhesive tape.

  In the illustrated embodiment, the polishing pad 327 mounted on the lower surface of the support base 326 is formed by mixing diamond abrasive grains in the felt. A plurality of grooves 327 a formed in a lattice shape are provided on the lower surface (polishing surface) of the polishing pad 327. In the illustrated embodiment, the plurality of grooves 327a have a width of 4 mm, a depth of 3 mm, and are formed at intervals of 20 mm. The polishing tool 325 configured as described above is positioned on the lower surface of the tool mounting member 324 fixed to the lower end of the rotary spindle 322, and is a support base for the polishing tool 325 through a through hole formed in the tool mounting member 324. The fastening bolt 328 (see FIG. 1) is screwed into the blind screw hole 326 a formed in 326 to be attached to the tool attachment member 324.

  Referring back to FIG. 1, the polishing apparatus 1 in the illustrated embodiment moves the polishing unit 3 in the vertical direction along the pair of guide rails 221 and 221 (a direction perpendicular to a holding surface of a chuck table described later). ) Is provided with a polishing feed means 4 which is moved. The polishing feed means 4 includes a male threaded rod 41 disposed on the front side of the upright wall 22 and extending in the vertical direction. The male screw rod 41 is rotatably supported by bearing members 42 and 43 whose upper end and lower end are attached to the upright wall 22. The upper bearing member 42 is provided with a pulse motor 44 as a drive source for rotationally driving the male screw rod 41, and the output shaft of the pulse motor 44 is connected to the male screw rod 41 by transmission. A connecting portion (not shown) that protrudes rearward from the center portion in the width direction is also formed on the rear surface of the movable base 31, and a through female screw hole extending in the vertical direction is formed in this connecting portion, The male screw rod 41 is screwed into the female screw hole. Therefore, when the pulse motor 44 rotates in the forward direction, the moving base 31, that is, the polishing unit 3 is lowered or moved forward, and when the pulse motor 44 rotates in the reverse direction, the moving base 31, that is, the polishing unit 3 is raised or moved backward.

  Continuing the description with reference to FIGS. 1 and 4, the chuck table mechanism 5 is disposed in the main portion 21 of the housing 2. The chuck table mechanism 5 includes a moving base 51 and a chuck table 6 disposed on the moving base 51. The moving base 51 is placed on a pair of guide rails 23, 23 extending on the main portion 21 of the housing 2 in the direction indicated by the arrows 23a and 23b which is the front-rear direction (the direction perpendicular to the front surface of the upright wall 22). A polishing tool which is slidably mounted and which constitutes the workpiece loading / unloading area 24 (position indicated by a solid line in FIG. 4) and the spindle unit 32 shown in FIG. 325 is moved between the polishing pad 327 and the polishing area 25 (position indicated by a two-dot chain line in FIG. 4).

The chuck table 6 is rotatably supported by the moving base 51 and is rotated by a servo motor 53 as a rotation driving means connected to a rotation shaft (not shown) attached to the lower end of the chuck table 6. The illustrated chuck table mechanism 5 includes a cover member 54 that has a hole through which the chuck table 6 is inserted and covers the movable base 51 and the like. The cover member 54 is configured to be movable together with the movable base 51. ing. Hereinafter, the chuck table 6 will be described with reference to FIGS. 5 and 6.

  As shown in FIG. 5, the chuck table 6 in the illustrated embodiment includes a holding table 61 having a holding surface that holds a workpiece, and a support member 62 that supports the holding table 61. It is supported on a support base 63. The holding table 61 includes a frame body 611 and a suction chuck 612 disposed on the upper surface of the frame body 611. The frame body 611 is formed of silicon carbide (SiC), and a circular fitting recess 611a is provided on the upper surface. A circular suction chamber 611b and a circular suction chamber 611b are provided below the fitting recess 611a. Annular suction chambers 611c and 611d are provided. The suction chamber 611b and the annular suction chamber 611c are communicated with each other through a communication groove 611f provided in the partition wall 611e, and the annular suction chamber 611c and the annular suction chamber 611d are provided in a communication groove 611h provided in the partition wall 611g. It is communicated by. The frame body 611 of the holding table 61 formed in this way is provided with a plurality of bolt insertion holes 611j on the outer peripheral portion, and a support member by fastening bolts 610 inserted and arranged through the plurality of bolt insertion holes 611j. 62 is fixed. The suction chuck 612 is formed in a disk shape from an appropriate porous material such as porous ceramics mainly composed of silicon carbide (SiC), and is fitted into the fitting recess 611a of the frame 611. The suction chuck 612 fitted in the fitting recess 611a of the frame 611 in this way functions as a holding surface for holding the workpiece.

  The support member 62 constituting the chuck table 6 is formed in a circular shape having the same outer diameter as the outer diameter of the frame body 611 of the holding table 61 as shown in FIG. A fitting convex portion 621 that fits into a fitting concave portion 631 formed on the upper surface is provided. The support member 62 thus formed has a cooling medium flow passage 622 through which a cooling medium for cooling the holding table 61 flows. As shown in FIG. 6, the cooling medium flow path 622 includes a first cooling medium flow path 622A formed from one end 622a provided in the central portion to one half of the upper surface of the support member 62, and the first cooling medium flow path 622A. The first cooling medium flow path 622A communicates with the second cooling medium flow path 622B that communicates with the other end 622b that is formed in the other half of the upper surface of the support member 62 and communicates with the other end 622b. Further, as shown in FIG. 5, the support member 62 has a first communication path 623 that communicates with one end 622 a of the cooling medium flow path 622 and a second communication path that communicates with the other end 622 b of the cooling medium flow path 622. 624 is provided. A suction passage 625 that communicates with a circular suction chamber 611b formed in the frame 611 of the table 61 is provided at the center of the support member 62 thus configured. The suction passage 625 is connected to suction means (not shown) via a passage 632 provided in the support base 63. Therefore, when a suction means (not shown) is operated, the suction chuck 612 is negatively passed through the passage 632, the suction passage 625, the circular suction chamber 611b, the communication groove 611f, the annular suction chamber 611c, the communication groove 611h, and the annular suction chamber 611d. The pressure acts to suck and hold the workpiece placed on the suction chuck 612.

  The first communication path 623 and the second communication path 624 provided in the support member 62 of the chuck table 6 configured as described above are the paths 633 and 634 provided in the support base 63 and the path 633. Are connected to the cooling medium supply means 7 via communication pipes 635 and 636 connected to 634 and 634.

  The cooling medium supply means 7 includes a cooling medium cooling means 71 for cooling the cooling medium, a pump 72 for supplying the cooling medium cooled by the cooling medium cooling means 71, and the cooling medium supplied by the pump 72. A cooling medium delivery pipe 73 to be sent out, and a cooling medium return pipe for returning the cooling medium circulating through the cooling medium flow passage 622 provided in the support member 62 of the chuck table 6 to the cooling medium cooling means 71 to the cooling medium cooling means 71. 74, an electromagnetic switching valve 75 disposed between the cooling medium delivery pipe 73 and the cooling medium return pipe 74 and the communication pipes 635 and 636. In the state shown in FIG. 5 in which the electromagnetic switching valve 75 is deenergized (OFF), the cooling medium delivery pipe 73 and the communication pipe 635 communicate with each other, and the communication pipe 636 and the cooling medium return pipe 74 communicate with each other. (First form). Further, when energized (ON), the electromagnetic switching valve 75 communicates the cooling medium delivery pipe 73 and the communication pipe 636 and also communicates the communication pipe 635 and the cooling medium return pipe 74 (second form).

  In the first embodiment, the cooling medium sent to the cooling medium delivery pipe 73 by the pump 72 is provided in the communication pipe 635, the passage 633 provided in the support base 63, and the support member 62 constituting the chuck table 6. The first communication path 623, the one end 622a of the cooling medium flow path 622, the first cooling medium flow path 622A, the second cooling medium flow path 622B, the other end 622b of the cooling medium flow path 622, the second communication It is circulated through the passage 624, the passage 634 provided in the support base 63, the communication pipe 636, the cooling medium return pipe 74, and the cooling medium cooling means 71. In the second embodiment, the cooling medium sent to the cooling medium delivery pipe 73 by the pump 72 is the communication pipe 636, the passage 634 provided in the support base 63, and the support member 62 constituting the chuck table 6. The second communication path 624, the other end 622b of the cooling medium flow path 622, the second cooling medium flow path 622B, the first cooling medium flow path 622A, the one end 622a of the cooling medium flow path 622, and the first Are circulated through the communication passage 623, the passage 633 provided in the support base 63, the communication pipe 635, the cooling medium return pipe 74, and the cooling medium cooling means 71. As a result of the circulation of the cooling medium in this manner, the support member 62 provided with the cooling medium flow path 622 and the frame body 611 of the holding table 61 and the suction chuck 612 in contact with the cooling medium flowing through the cooling medium flow path 622 are cooled. I'm damned.

  Returning to FIG. 4, the explanation will continue. The polishing apparatus in the illustrated embodiment moves the chuck table mechanism 5 along the pair of guide rails 23 in parallel with the holding surface which is the upper surface of the chuck table 6 by arrows 23 a and 23 b. A chuck table mechanism moving means 56 for moving in the direction shown is provided. The chuck table mechanism moving means 56 includes a male screw rod 561 that is disposed between the pair of guide rails 23 and extends parallel to the guide rail 23, and a servo motor 562 that rotationally drives the male screw rod 561. The male screw rod 561 is screwed into a screw hole 511 provided in the support base 51, and its tip is rotatably supported by a bearing member 563 attached by connecting a pair of guide rails 23, 23. ing. The servo motor 562 has a drive shaft connected to the base end of the male screw rod 561 by transmission. Accordingly, when the servo motor 562 rotates in the forward direction, the moving base 51, that is, the chuck table mechanism 5 moves in the direction indicated by the arrow 23a, and when the servo motor 562 rotates in the reverse direction, the support base 51, that is, the chuck table mechanism 5, moves in the direction indicated by the arrow 23b. It can be moved. The chuck table mechanism 5 that is moved in the directions indicated by the arrows 23a and 23b is selectively positioned in a workpiece loading / unloading area indicated by a solid line and a polishing area indicated by a two-dot chain line in FIG.

  The description will be continued with reference to FIG. 1. On both sides of the moving base 51 constituting the chuck table mechanism 5 in the moving direction, the cross-sectional shape is an inverted channel shape as shown in FIG. Bellows means 8 and 9 are attached to cover the guide rails 23 and 23, the male screw rod 561, the servo motor 562 and the like. The bellows means 8 and 9 can be formed from any suitable material such as campus cloth. The front end of the bellows means 8 is fixed to the front wall of the rear half of the main portion 21 constituting the housing 2, and the rear end is fixed to the front end surface of the moving base 51 of the chuck table mechanism 5. The front end of the bellows means 9 is fixed to the rear end surface of the moving base 51 of the chuck table mechanism 5, and the rear end is fixed to the front surface of the upright wall 22 of the apparatus housing 2. When the chuck table mechanism 5 is moved in the direction indicated by the arrow 23a, the bellows means 8 is expanded and the bellows means 9 is contracted, and when the chuck table mechanism 5 is moved in the direction indicated by the arrow 23b, the bellows means. 8 is contracted and the bellows means 9 is extended.

  The description will be continued based on FIG. 1. On the front half of the main portion 21 of the apparatus housing 2, a first cassette 11, a second cassette 12, a workpiece temporary placing means 13, and a cleaning means are provided. 14, a workpiece conveying means 15, a workpiece carrying-in means 16 and a workpiece carrying-out means 17 are arranged. The first cassette 11 stores a workpiece before polishing and is placed in a cassette carry-in area in the main portion 21 of the apparatus housing 2. The workpiece to be accommodated in the first cassette 11 is, for example, a semiconductor wafer W and is accommodated with the back surface facing up with the protective tape T attached to the surface. The second cassette 12 is placed in a cassette unloading area in the main portion 21 of the apparatus housing 2 and stores the semiconductor wafer W after polishing. The workpiece temporary mounting means 13 is disposed between the first cassette 11 and the workpiece loading / unloading area 24, and temporarily mounts the semiconductor wafer W before polishing. The cleaning means 14 is disposed between the workpiece loading / unloading area 24 and the second cassette 12 and cleans the semiconductor wafer W after polishing. The workpiece transfer means 15 is disposed between the first cassette 11 and the second cassette 12 and carries the semiconductor wafer W stored in the first cassette 11 to the workpiece temporary placement means 13. At the same time, the semiconductor wafer W cleaned by the cleaning means 14 is transported to the second cassette 12. The workpiece carrying-in means 16 is disposed between the workpiece temporary placing means 13 and the workpiece carrying-in / out area 24, and is placed on the workpiece temporary placing means 13 before polishing. The semiconductor wafer W is transferred onto the chuck table 6 of the chuck table mechanism 5 positioned in the workpiece loading / unloading area 24. The workpiece unloading means 17 is disposed between the workpiece loading / unloading area 24 and the cleaning means 14, and is mounted on the chuck table 6 positioned in the workpiece loading / unloading area 24. The processed semiconductor wafer W is transported to the cleaning means 14. Further, the polishing apparatus in the illustrated embodiment includes a cleaning water spray nozzle 18 that cleans the holding surface of the chuck table 6 at the center of the main portion 21 of the apparatus housing 2. The cleaning water spray nozzle 18 ejects cleaning water toward the chuck table 6 in a state where the chuck table mechanism 5 is positioned in the workpiece loading / unloading area 24.

  The first cassette 11 containing the semiconductor wafer W as a workpiece is placed in a predetermined cassette carry-in area in the main portion 21 of the apparatus housing 2. Then, when all the semiconductor wafers W before being polished that were accommodated in the first cassette 11 placed in the cassette carry-in area are unloaded, a plurality of semiconductor wafers W are accommodated in place of the empty cassette 11. A new cassette 11 is manually placed in the cassette carry-in area. On the other hand, when a predetermined number of polished semiconductor wafers W are loaded into the second cassette 12 placed in a predetermined cassette unloading area in the main portion 21 of the apparatus housing 2, the second cassette 12 is manually moved. It is unloaded and a new empty second cassette 12 is placed.

The polishing apparatus 1 in the illustrated embodiment is configured as described above, and the operation thereof will be described below.
The semiconductor wafer W as a workpiece before polishing, which is accommodated in the first cassette 11, is transported by the vertical movement and advancing / retreating operation of the workpiece conveying means 15 and is placed on the workpiece temporary placing means 13. The The semiconductor wafer W mounted on the workpiece temporary mounting means 13 is positioned in the workpiece loading / unloading area 24 by the turning operation of the workpiece loading means 16 after being centered here. The chuck table mechanism 5 is mounted on the chuck chuck 612 of the chuck table 6. When the semiconductor wafer W is placed on the suction chuck 612 of the chuck table 6, the suction means (not shown) is operated to operate the passage 632, the suction passage 625, the circular suction chamber 611b, the communication groove 611f, A negative pressure acts on the suction chuck 612 via the annular suction chamber 611c, the communication groove 611h, and the annular suction chamber 611d, and the semiconductor wafer W placed on the suction chuck 612 is sucked and held (wafer holding step).

  When the semiconductor wafer W is sucked and held on the suction chuck 612 of the chuck table 6, the chuck table mechanism moving means 56 is operated to move the chuck table 6 in the direction indicated by the arrow 23a, and the chuck table 6 is moved to the polishing area 25. Position. When the chuck table 6 is positioned in the polishing area 25 in this way, the chuck table 6 holding the semiconductor wafer W is rotated at a rotational speed of 200 to 500 rpm, for example, in the direction indicated by 6a in FIG. Is driven to rotate the polishing tool 325 in the direction indicated by 325a in FIG. 7 at, for example, 200 to 500 rpm, and the pulse motor 44 of the polishing feed means 4 is driven to rotate forward so that the polishing unit 3 is lowered or moved forward. The polishing pad 327 of the tool 325 is pressed against the back surface (upper surface) of the semiconductor wafer W on the chuck table 6 with a predetermined polishing pressure. As a result, the back surface (upper surface) of the semiconductor wafer W is dry-polished by the polishing pad 327 to remove residual processing strain (polishing process).

  During the polishing process, the cooling medium supply means 7 is operated to circulate the cooling medium through the cooling medium flow path 622 provided in the support member 62, and the cooling medium flow path 622 is provided. The frame body 611 and the suction chuck 612 of the holding table 61 in contact with the cooling medium flowing through the support member 62 and the cooling medium flow path 622 are cooled. By cooling the holding table 61 in this way, the semiconductor wafer W held on the holding table 61 is cooled, and an increase in frictional heat due to dry polishing is suppressed, thereby preventing deterioration in device quality due to frictional heat. . However, in the first embodiment shown in FIG. 5 in which the electromagnetic switching valve 75 of the cooling medium supply means 7 is de-energized (OFF), the cooling medium is supplied from the one end 622a of the cooling medium flow passage 622 to the first position as described above. Since the cooling medium flow path 622A, the second cooling medium flow path 622B, and the other end 622b of the cooling medium flow path 622 flow in this order, the holding table 61 has the region where the first cooling medium flow path 622A is provided first. The region where the second cooling medium flow path 622B is provided is cooled afterward. Accordingly, the region where the second cooling medium flow passage 622B is provided is cooled by the warmed cooling medium by cooling the region where the first cooling medium flow passage 622A is provided, and the cooling effect is low. There is a temperature difference between the region where the cooling medium flow passage 622A is provided and the region where the second cooling medium flow passage 622B is provided. Therefore, when the electromagnetic switching valve 75 of the cooling medium supply means 7 is de-energized (OFF) and operated in the first mode for 30 to 60 seconds, for example, the electromagnetic switching valve 75 is energized (ON) and configured in the second mode, for example. Operates for 30-60 seconds. Thus, by repeatedly performing the deenergization (OFF) and the energization (ON) of the electromagnetic switching valve 75, the workpiece holding area of the holding table 61 can be uniformly and effectively cooled.

  When the polishing operation is completed as described above, the operation of the cooling medium supply means 7 is stopped, the pulse motor 44 of the polishing feed means 4 is driven in reverse to raise the spindle unit 32 to a predetermined position, and the polishing tool 325 is driven. The rotation of the chuck table 6 is stopped. Next, the chuck table mechanism 5 is moved in the direction indicated by the arrow 23 b and is positioned in the workpiece loading / unloading area 24. If the chuck table mechanism 5 is positioned in the workpiece loading / unloading area 24, the suction holding of the polished semiconductor wafer on the chuck table 6 is released, and the semiconductor wafer W whose suction holding is released is processed. It is unloaded by the object unloading means 17 and conveyed to the cleaning means 14. The semiconductor wafer W transferred to the cleaning unit 14 is cleaned here and then stored in a predetermined position of the second cassette 12 by the workpiece transfer unit 15.

Although the present invention has been described based on the illustrated embodiment, the present invention is not limited to the embodiment, and various modifications are possible within the scope of the gist of the present invention.
For example, in the above-described embodiment, the cooling medium flow path 622 is provided on the upper surface of the support member 62 constituting the chuck table 6, but the cooling medium flow path is formed on the lower surface of the frame body 611 of the holding table 61. It may be provided.
Further, in the above-described embodiment, the cooling medium flow path 622 is formed in the first cooling medium flow path 622A formed in one approximately half region of the upper surface of the support member 62, and the other substantially half region. Although the example of the two cooling medium flow paths 622B is shown, the cooling medium flow path may be formed in a spiral shape from the center to the outer periphery.
In the above-described embodiment, the present invention is applied to a chuck table mechanism that is mounted on a polishing apparatus and holds a workpiece. However, the chuck table mechanism according to the present invention is a workpiece to be held on a chuck table. The present invention can be widely applied to a chuck table mechanism of a processing apparatus that processes an object while cooling it.

2: Device housing 3: Polishing unit 31: Moving base 32: Spindle unit 321: Spindle housing 322: Rotating spindle 323: Servo motor 324: Tool mounting member 325: Polishing tool 326: Support base 327: Polishing pad 4: Polishing Feed means 44: Pulse motor 5: Chuck table mechanism 51: Moving base 56: Chuck table mechanism moving means 6: Chuck table 61: Holding table 62: Support member 622: Cooling medium flow path 63: Support base 7: Cooling medium Supply means 71: Cooling medium cooling means 72: Pump 73: Cooling medium delivery pipe 74: Cooling medium return pipe 11: First cassette 12: Second cassette 13: Temporary workpiece placing means 14: Cleaning means 15: Workpiece conveying means 16: Workpiece carrying-in means 17: Workpiece carrying-out means 8: cleaning water injection nozzle
W: Semiconductor wafer

Claims (1)

A chuck table mechanism comprising: a chuck table that holds a workpiece; and a cooling medium supply unit that supplies a cooling medium for cooling the chuck table.
The chuck table includes a holding table having a holding surface that holds a workpiece, and a support member that supports the holding table, and a cooling medium that flows a cooling medium for cooling the holding table to the support member. A first communication path that communicates with one end of the flow path and a second communication path that communicates with the other end of the cooling medium flow path;
The cooling medium supply means includes a cooling medium cooling means for cooling the cooling medium, a pump for feeding the cooling medium cooled by the cooling medium cooling means, and a cooling medium for sending the cooling medium fed by the pump The cooling medium return pipe that returns the cooling medium that has cooled the holding table of the chuck table to the cooling medium cooling means, the cooling medium supply pipe, and the first communication path communicate with the second pipe. The first communication path and the cooling medium return pipe, the cooling medium delivery pipe and the second communication path, and the first communication path and the cooling medium return pipe. A switching valve that can be switched to the second form that communicates,
A chuck table mechanism characterized by that.

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