JP2020080390A - Chuck table and processing apparatus - Google Patents

Abstract

A chuck table capable of easily and appropriately holding a warped workpiece is provided. A chuck table for holding a plate-shaped work piece includes a holding surface for sucking and holding the work piece; and a first elastic sealing member and a second elastic sealing member provided on a holding surface, wherein the holding surface includes a central suction area for sucking a central area of the workpiece and a holding part having two suction paths. , an outer peripheral suction area surrounding the central suction area and sucking the outer peripheral area of the workpiece, one end side of the first suction path is connected to the central suction area, and one end side of the second suction path is connected to the outer peripheral area. Connected with the suction area, a first elastic sealing member surrounds the central suction area and is arranged such that its upper end protrudes from the holding surface and contacts the workpiece, and a second elastic sealing member surrounds the outer peripheral suction area. , and is arranged so that the upper end protrudes from the holding surface and contacts the workpiece. [Selection drawing] Fig. 2

Description

  The present invention relates to a chuck table that holds a plate-shaped workpiece, and a processing device that processes the workpiece held by the chuck table.

  A resin package substrate in which a plurality of device chips arranged on a substrate are covered with a resin layer (mold resin), or a WL-CSP (Wafer Level Chip Size Package) in which a plurality of devices formed on a semiconductor wafer are covered with a resin layer A package device is manufactured by dividing various package substrates represented by the above. This package device is incorporated in various electronic devices represented by mobile phones and personal computers.

  The division of the package substrate is performed by using a processing device that processes the package substrate. For example, as a processing device, a cutting device including a chuck table that holds a package substrate and a cutting unit that is equipped with an annular cutting blade that cuts the package substrate held by the chuck table is used. Further, in recent years, a method of dividing a package substrate by using a laser processing apparatus provided with a laser irradiation unit that irradiates a laser beam onto a package substrate held by a chuck table has been used.

  When processing a workpiece such as a package substrate with a processing device, a negative pressure of a suction source is applied to the holding surface of the chuck table while the workpiece is placed on the holding surface of the chuck table. Is suction-held by the chuck table. Then, the workpiece suctioned and held by the chuck table is subjected to predetermined processing by the processing unit such as the above cutting unit or laser irradiation unit.

  In addition, the workpiece may be warped in the manufacturing process. For example, when a package substrate is manufactured, if the resin layer is cooled after being subjected to heat treatment for curing the resin layer, the resin layer may shrink and the package substrate may warp. When the work piece warps, the work piece and the holding surface of the chuck table do not make proper contact, and the negative pressure acting on the holding surface leaks from the gap between the work piece and the holding surface, causing the chuck to move. The work piece may not be held sufficiently by the table.

  Therefore, there has been proposed a method for properly holding a warped workpiece by a chuck table. For example, Patent Document 1 discloses a method in which an adhesive tape is attached to a workpiece and the workpiece is held on a chuck table via the adhesive tape. According to this method, the holding surface of the chuck table is covered with the adhesive tape, and leakage of negative pressure acting on the holding surface is prevented, so that the workpiece can be appropriately suction-held by the chuck table. ..

JP, 2013-93383, A

  As described above, when the workpiece has a warp, a gap may occur between the workpiece and the holding surface of the chuck table, and it may be difficult to appropriately suction and hold the workpiece by the chuck table. .. Further, in the method of holding the workpiece by the chuck table via the adhesive tape, it is necessary to attach the adhesive tape to the workpiece, which increases the labor and cost required for holding the workpiece.

  The present invention has been made in view of the above problems, and is a chuck table capable of easily and appropriately holding a workpiece having a warp, and processing for processing the workpiece held by the chuck table. The purpose is to provide a device.

  According to one aspect of the present invention, a chuck table for holding a plate-shaped work piece is connected to a holding surface for holding the work piece by suction, and the holding surface and a suction source for generating a suction force. A holding portion having a first suction path and a second suction path, and a first elastic seal member and a second elastic seal member provided on the holding surface, the holding surface having the workpiece. A central suction area for sucking a central area of the workpiece, and an outer peripheral suction area surrounding the central suction area for sucking an outer peripheral area of the workpiece. One end side of the first suction path has the central suction area. And one end side of the second suction passage is connected to the outer circumference suction area, the first elastic seal member surrounds the central suction area, and the upper end projects from the holding surface. A chuck table is provided that is arranged so as to come into contact with the second elastic sealing member, surrounds the outer peripheral suction region, and has an upper end protruding from the holding surface so as to come into contact with the workpiece. It

  In addition, preferably, the first elastic seal member and the second elastic seal member are configured by tubes made of resin. Further, preferably, the other end side of the first suction passage is connected to the suction source via a first communication passage provided with a first valve, and the other end side of the second suction passage includes a second valve. It is connected to the suction source via a second communication path provided.

  Further, according to an aspect of the present invention, there is provided a processing device including the chuck table, a processing unit that processes a workpiece held by the chuck table, and a transport unit that transports the workpiece. The transport unit includes a main body portion, a suction portion connected to the main body portion, which includes a suction pad for sucking and holding the workpiece, and the workpiece holding surface of the chuck table. And a pressing portion connected to the main body, the pressing portion pressing the suction surface of the suction pad toward the suction surface of the suction pad from a position below the pressing surface to the same as the pressing surface. There is provided a processing device configured to be arranged at a height or a position above the pressing surface.

  A chuck table according to an aspect of the present invention includes a holding surface that holds a workpiece, and the holding surface sucks a central suction area that sucks a central area of the workpiece and an outer peripheral area of the workpiece. A peripheral suction area. For example, the chuck table sucks the central region of the workpiece in the central suction region to reduce the warp of the workpiece, and then sucks the outer peripheral region of the workpiece in the outer peripheral suction region to remove the workpiece. Hold on the holding surface.

  When the workpiece is sucked by the chuck table, the workpiece is deformed along the holding surface of the chuck table, and the warp of the workpiece is corrected. Therefore, the negative pressure can be prevented from leaking from the gap between the workpiece and the holding surface, and the workpiece can be appropriately held.

  Further, when the above chuck table is used, it is possible to hold a workpiece having a warp without performing work such as sticking an adhesive tape having a size that covers the holding surface of the chuck table to the back surface of the workpiece. Therefore, it is possible to easily hold a warped work piece without increasing the labor and cost required to hold the work piece.

1A is a plan view showing a workpiece, FIG. 1B is a bottom view showing the workpiece, and FIG. 1C is a front view showing the workpiece. 2A is a plan view showing the chuck table, and FIG. 2B is a sectional view showing the chuck table. It is a partial cross-section front view which shows the state where the to-be-processed object was conveyed above the chuck table. It is a partial cross section front view showing the state where the central region of the work piece was held by the central suction region of the chuck table. It is a partial cross-sectional front view which shows the state where the outer peripheral area|region of the to-be-processed object was hold|maintained at the outer peripheral suction area of a chuck table.

  The present embodiment will be described below with reference to the accompanying drawings. First, a configuration example of the workpiece held by the chuck table according to the present embodiment will be described. 1A is a plan view showing the workpiece 11, FIG. 1B is a bottom view showing the workpiece 11, and FIG. 1C is a front view showing the workpiece 11. .

  The workpiece 11 includes a plate-shaped substrate 13 having a front surface 13a and a back surface 13b and formed in a rectangular shape in a plan view, and a device including a device such as an IC (Integrated Circuit) and an LSI (Large Scale Integration). And a plurality of device chips (not shown) arranged on the front surface 13a side. A resin layer (mold resin) 15 that covers and seals a plurality of device chips is formed on the surface 13 a side of the substrate 13.

  Although the package substrate formed by covering the device chip with the resin layer 15 is used as the workpiece 11 here, the type, material, shape, structure, size, etc. of the workpiece 11 are not limited. .. For example, the workpiece 11 may be a disc-shaped semiconductor wafer made of a material such as silicon and having devices such as IC and LSI formed on the front surface side. Further, the workpiece 11 may be a wafer made of a material other than silicon (GaAs, InP, GaN, SiC, etc.), glass, ceramics, resin, metal or the like.

  As shown in FIG. 1B, the workpiece 11 is provided with a plurality of device regions 11a defined by a plurality of planned dividing lines (streets) 17 arranged in a grid pattern so as to intersect each other. The chips are arranged in the device area 11a. Further, as shown in FIG. 1C, the workpiece 11 includes a central region 11b located on the central side of the workpiece 11 and an outer peripheral region 11c surrounding the central region 11b and including the outer peripheral edge of the workpiece 11. With.

  By dividing the workpiece 11 along the dividing line 17, a plurality of package devices each including a device chip can be obtained. It should be noted that a plurality of markers 19 indicating the positions of the planned dividing lines 17 are provided on the back surface 13b side of the substrate 13, and the markers 19 serve as marks for processing the workpiece 11 along the planned dividing lines 17. Become.

  On the back surface 13b side of the substrate 13, a plurality of electrodes 21 made of metal are arranged along the planned dividing line 17. The electrode 21 is connected to a device chip arranged on the front surface 13 a side of the substrate 13 via a metal wire (not shown) or the like, and a part of the electrode 21 is exposed on the back surface 13 b side of the substrate 13. The electrode 21 functions as a connection electrode when mounting the package device on another mounting substrate or the like after the workpiece 11 is divided into a plurality of package devices.

  For the division of the workpiece 11, a processing device such as a cutting device or a laser processing device can be used. The cutting device includes a chuck table that holds the workpiece 11, and a processing unit (cutting unit) to which an annular cutting blade that cuts the workpiece 11 is mounted. The cutting unit includes a spindle having a cutting blade mounted on one end side and the other end side connected to a rotary drive source such as a motor. The workpiece 11 is cut by rotating the cutting blade by the power of the rotary drive source and making a cut in the workpiece 11.

  Further, the laser processing apparatus includes a chuck table that holds the workpiece 11 and a processing unit (laser irradiation unit) that irradiates the workpiece 11 with a laser beam. For example, the laser irradiation unit includes a laser oscillator that oscillates a pulse laser beam and a condenser that condenses the pulse laser beam oscillated from the laser oscillator. A part of the workpiece 11 can be removed by irradiating the workpiece 11 with a laser beam and subjecting the workpiece 11 to ablation processing or the like.

  When processing the workpiece 11 using the processing device, the workpiece 11 is held by the holding surface of the chuck table included in the processing device. Specifically, with the workpiece 11 placed on the holding surface of the chuck table, a negative pressure of the suction source is applied to the holding surface. As a result, the workpiece 11 is suction-held by the chuck table. Then, the workpiece 11 suction-held by the chuck table is subjected to predetermined processing by the processing unit.

  Here, the workpiece 11 may be warped in the manufacturing process. For example, when the resin layer 15 is cooled after heat treatment for curing the resin layer 15, the resin layer 15 contracts, and the workpiece 11 is warped as shown in FIG. 1C. There is. It should be noted that FIG. 1C shows the workpiece 11 that is curved so that the surface 13 a side of the substrate 13 is curved in a concave shape.

  When the workpiece 11 is warped, the workpiece 11 and the holding surface of the chuck table do not properly contact each other, and the negative pressure acting on the holding surface leaks from the gap between the workpiece 11 and the holding surface. However, the workpiece 11 may not be held sufficiently by the chuck table. Therefore, when the workpiece 11 having a warp is suction-held by the chuck table, it is preferable to deform the workpiece 11 along the holding surface of the chuck table and correct the warp of the workpiece 11.

  The chuck table according to the present embodiment includes a holding surface for holding the workpiece 11, and the holding surface has a central suction area for sucking the central area 11b of the workpiece 11 and an outer peripheral area 11c of the workpiece 11. And an outer peripheral suction area for sucking. In the chuck table, for example, the central area 11b is sucked in the central suction area to reduce the warp of the workpiece 11, and then the outer peripheral area 11c is sucked in the outer circumferential suction area to hold the workpiece 11 on the holding surface. To do.

  When the workpiece 11 is sucked by the chuck table, the workpiece 11 is deformed along the holding surface of the chuck table, and the warp of the workpiece 11 is corrected. Therefore, the negative pressure can be prevented from leaking from the gap between the workpiece 11 and the holding surface, and the workpiece 11 can be held appropriately. The details of the chuck table according to the present embodiment will be described below.

  2A is a plan view showing the chuck table 4 provided in the processing apparatus 2, and FIG. 2B is a sectional view showing the chuck table 4. The processing device 2 performs predetermined processing on the workpiece 11 held by the chuck table 4. For example, when dividing the workpiece 11 along the planned dividing line 17, the processing device 2 is a cutting device that cuts the workpiece 11 with a cutting blade, or the workpiece 11 is processed by laser beam irradiation. A laser processing device or the like is used.

  However, the processing device 2 is not limited in its type as long as it performs predetermined processing on the workpiece 11. For example, the processing device 2 may be a grinding device that grinds the workpiece 11, a polishing device that polishes the workpiece 11, or the like.

  The chuck table 4 includes a holding unit 6 that holds the workpiece 11. The holding portion 6 is formed in a rectangular shape in a plan view corresponding to the shape of the workpiece 11, and the upper surface of the holding portion 6 constitutes a holding surface 6a for sucking and holding the workpiece 11.

  The holding surface 6a is formed flat along the horizontal direction, and has a central suction area 6b that sucks the central area 11b (see FIG. 1C) of the workpiece 11 and a central suction area 6b that surrounds the central suction area 6b. An outer peripheral suction area 6c for sucking the outer peripheral area 11c (see FIG. 1C) of the workpiece 11 is provided. The shape of the holding portion 6 is appropriately changed according to the shape of the workpiece 11 and the like.

  Further, the holding portion 6 includes a first suction passage 6d and a second suction passage 6e formed from the upper surface (holding surface 6a) of the holding portion 6 toward the lower surface. One end side (upper end side) of the first suction passage 6d is connected to the central suction region 6b, and the other end side (lower end side) is connected to the first communication passage 8a. Further, one end side (upper end side) of the second suction passage 6e is connected to the outer peripheral suction region 6c, and the other end side (lower end side) is connected to the second communication passage 8b. The number of the first suction passages 6d and the second suction passages 6e is not limited.

  The first communication passage 8a and the second communication passage 8b are each connected to a suction source 10 such as an ejector that generates a suction force. That is, the other end side (lower end side) of the first suction passage 6d is connected to the suction source 10 via the first communication passage 8a, and the other end side (lower end side) of the second suction passage 6e is the second communication passage 8b. Is connected to the suction source 10 via. The first communication passage 8a includes a first valve 12a that controls the flow of fluid flowing between the suction source 10 and the central suction region 6b, and the second communication passage 8b includes the suction source 10 and the outer peripheral suction region 6c. And a second valve 12b for controlling the flow of the fluid flowing between and.

  When the first valve 12a is opened, the negative pressure of the suction source 10 acts on the central suction area 6b via the first suction passage 6d. Further, when the second valve 12b is opened, the negative pressure of the suction source 10 acts on the outer peripheral suction area 6c via the second suction passage 6e.

  Further, on the holding surface 6a side of the holding portion 6, a first groove 6f surrounding the central suction area 6b and a second groove 6g surrounding the outer circumference suction area 6c are formed. Each of the first groove 6f and the second groove 6g is formed in a rectangular shape in a plan view, and has a so-called dovetail groove shape (FIG. 2(B)) in which the width increases from the upper end (holding surface 6a) toward the bottom. It is formed in a trapezoidal shape in the sectional view shown in FIG.

  Further, the chuck table 4 includes a cylindrical first elastic seal member 14 and a second elastic seal member 16 which are elastic bodies and are deformable by application of an external force on the holding surface 6a. The first elastic seal member 14 and the second elastic seal member 16 are each configured by a closed loop tube made of resin, an O-ring, or the like.

  Particularly, by using a tube made of resin, the first elastic seal member 14 and the second elastic seal member 16 having high flexibility can be configured. As a result, when the workpiece 11 is held by the chuck table 4, the first elastic seal member 14 and the second elastic seal member 16 are easily deformed along the holding surface 6a (see FIGS. 4 and 5). It becomes easy to hold the workpiece 11 along the holding surface 6a. However, the materials and structures of the first elastic seal member 14 and the second elastic seal member 16 can be appropriately changed.

  The first elastic seal member 14 is fitted inside the first groove 6f, and the second elastic seal member 16 is fitted inside the second groove 6g. Therefore, the first elastic seal member 14 is arranged in a rectangular shape in plan view so as to surround the central suction area 6b. Further, the second elastic seal member 16 is arranged in a rectangular shape in plan view so as to surround the outer peripheral suction region 6c.

  The depth of the first groove 6f is smaller than the diameter of the first elastic seal member 14, and the depth of the second groove 6g is smaller than the diameter of the second elastic seal member 16. Therefore, the first elastic seal member 14 and the second elastic seal member 16 are arranged such that their upper ends project upward from the holding surface 6a.

  The width of the upper end of the first groove 6f (width of the first groove 6f on the holding surface 6a) is smaller than the diameter of the first elastic seal member 14, and the width of the upper end of the second groove 6g (on the holding surface 6a). The width of the second groove 6g) is preferably smaller than the diameter of the second elastic seal member 16. By forming the first groove 6f and the second groove 6g with such dimensions, the first elastic seal member 14 and the second elastic seal member 16 are unlikely to come off.

  When the workpiece 11 is processed by the processing device 2, the workpiece 11 is arranged on the holding surface 6a of the holding unit 6, and the first valve 12a and the second valve 12b are opened to suck the central suction area 6b and the outer circumference. A negative pressure of the suction source 10 is applied to each of the regions 6c. As a result, the workpiece 11 is suction-held by the chuck table 4.

  Hereinafter, a specific example of the procedure of holding the workpiece 11 by the chuck table 4 will be described. Here, a case where the workpiece 11 having a warp (see FIG. 1C) is held by the chuck table 4 will be described in particular.

  First, the workpiece 11 to be processed by the processing device 2 is conveyed above the chuck table 4. FIG. 3 is a partial cross-sectional front view showing a state in which the workpiece 11 is conveyed above the chuck table 4. The workpiece 11 is transported by using the transport unit 20 included in the processing device 2.

  The transport unit 20 includes a main body 22 that is rectangular in plan view. The upper surface side of the main body 22 is connected to a transfer arm 24 included in the moving mechanism, and the movement of the main body 22 is controlled by this moving mechanism. The shape of the main body 22 is not limited.

  A plurality of suction sections 26 are connected to the lower surface side of the main body section 22. The suction unit 26 is provided at a position corresponding to the workpiece 11 and holds the workpiece 11 by suction. For example, the main body portion 22 is provided with two suction portions 26 at positions corresponding to the resin layer 15. However, the number and arrangement of the suction portions 26 can be appropriately set according to the type, structure, size, weight, etc. of the workpiece 11.

  Each of the suction portions 26 is formed in a column shape from the lower surface of the main body portion 22 downward. Specifically, the suction part 26 includes a connection part 28 connected to the lower surface side of the main body part 22, and a rod-shaped rod member 30 having one end side (upper end side) inserted into the connection part 28. The rod member 30 is supported so as to be movable in the vertical direction (vertical direction) with respect to the main body portion 22 and the connection portion 28. Further, a spring member 32 formed of a coil spring or the like is arranged around the rod member 30 so as to surround the rod member 30.

  A suction pad 34 for sucking the workpiece 11 is fixed to the other end side (lower end side) of the rod member 30. The lower surface of the suction pad 34 constitutes a suction surface 34 a that comes into contact with the workpiece 11 and sucks the workpiece 11, and the suction surface 34 a is a suction path (not shown) provided inside the suction unit 26. Is connected to a suction source (not shown) via. When the suction surface 34a is in contact with the workpiece 11, a negative pressure of a suction source is applied to the suction surface 34a, whereby the workpiece 11 is suction-held by the suction pad 34.

  One end side (upper end side) of the spring member 32 is in contact with the lower surface of the connecting portion 28, and the other end side (lower end side) is in contact with the upper surface of the suction pad 34. When an upward external force is applied to the suction pad 34, the rod member 30 moves in a direction to be inserted into the connection portion 28, and the spring member 32 sandwiched between the connection portion 28 and the suction pad 34 contracts. As a result, the suction pad 34 moves upward so as to approach the main body 22.

  As described above, when the suction pad 34 is configured to be movable in the vertical direction, the suction pad 34 will not move even when the workpiece 11 has a warp or when the thickness of the workpiece 11 varies. The workpiece 11 is brought into contact with the workpiece 11 following the shape of the workpiece 11. Therefore, the workpieces 11 having various shapes can be appropriately suction-held by the suction pad 34.

  Further, a plurality of pressing portions 36 are connected to the lower surface side of the main body portion 22 where the suction portion 26 is not provided. The pressing portion 36 is formed in a column shape downward from the lower surface of the main body portion 22 and is provided at a position corresponding to the workpiece 11. For example, six pressing portions 36 are provided in the main body portion 22 in a region corresponding to the outer peripheral region 11c of the workpiece 11 (in FIG. 3, a region corresponding to the resin layer 15 in the outer peripheral region 11c). However, the number and arrangement of the pressing portions 36 can be appropriately set according to the type, structure, size, rigidity, etc. of the workpiece 11.

  The pressing portion 36 presses the workpiece 11 downward (toward the holding surface 6a of the holding portion 6). Specifically, the lower surface of the pressing portion 36 constitutes a pressing surface 36 a that contacts the workpiece 11 and presses the workpiece 11. When the workpiece 11 is placed on the chuck table 4, the pressing surface 36a contacts the workpiece 11 and presses the workpiece 11 toward the holding surface 6a side of the holding portion 6 (see FIG. 5). As a result, the warp of the workpiece 11 is corrected. The details of the pressing of the work piece 11 by the pressing portion 36 will be described later.

  When the workpiece 11 is transported by the transport unit 20, first, the suction pads 34 of the plurality of suction portions 26 are brought into contact with the surface of the workpiece 11 (the surface of the resin layer 15 in FIG. 3) to suck the suction surface 34a. The negative pressure of the suction source is applied to. As a result, the workpiece 11 is suction-held by the transport unit 20. Then, the transport unit connected to the main body 22 moves the transport unit 20 above the chuck table 4. As a result, the workpiece 11 is conveyed above the chuck table 4 as shown in FIG.

  When the workpiece 11 is conveyed, the suction surface 34a of the suction pad 34 is arranged below the pressing surface 36a of the pressing portion 36 (see FIG. 3). Therefore, the pressing portion 36 does not come into contact with the workpiece 11 to prevent the suction pad 34 from holding the workpiece 11.

  Next, the first valve 12a is opened, and the negative pressure of the suction source 10 is applied to the central suction area 6b of the chuck table 4. Then, the transport unit 20 is lowered toward the holding surface 6 a of the holding unit 6.

  When the transport unit 20 is lowered, the back surface of the workpiece 11 (the back surface 13b of the substrate 13) comes into contact with the first elastic seal member 14 projecting from the holding surface 6a, and the first elastic seal member 14 is processed. It deforms along the shape of the back surface of 11. As a result, the space between the central region 11b of the workpiece 11 and the central suction region 6b is sealed, and the negative pressure leak acting on the central suction region 6b is prevented. In addition, after the workpiece 11 and the first elastic seal member 14 are in contact with each other, the first valve 12a may be opened to apply the negative pressure of the suction source 10 to the central suction region 6b.

  When the central region 11b of the workpiece 11 is sucked into the central suction region 6b, the first elastic seal member 14 is further deformed and buried in the first groove 6f, and the central region 11b extends along the central suction region 6b. Retained. FIG. 4 is a partial cross-sectional front view showing a state in which the central region 11b of the workpiece 11 is held by the central suction region 6b of the chuck table 4. As shown in FIG. 4, the central region 11b of the workpiece 11 is held along the flat central suction region 6b. As a result, the warp of the central region 11b is corrected, and the warp of the entire workpiece 11 is reduced.

  Next, the second valve 12b is opened, and the negative pressure of the suction source 10 is applied to the outer peripheral suction area 6c of the chuck table 4. Then, the transport unit 20 is further lowered toward the holding surface 6a of the holding portion 6.

  When the transport unit 20 is lowered, an upward force is applied from the workpiece 11 to the suction pad 34 of the suction section 26. As a result, the spring member 32 contracts, the rod member 30 is inserted into the connecting portion 28, and the suction pad 34 moves upward with respect to the main body portion 22. Then, the pressing surface 36a of the pressing portion 36 contacts the surface of the workpiece 11 (the surface of the resin layer 15 in FIG. 5) and presses the outer peripheral region 11c of the workpiece 11 toward the holding surface 6a of the holding portion 6. To do.

  As a result, the outer peripheral region 11c of the work piece 11 is pressed against the holding surface 6a, and the back surface of the work piece 11 (the back surface 13b of the substrate 13) comes into contact with the second elastic seal member 16 protruding from the holding surface 6a. Then, the second elastic seal member 16 deforms along the shape of the back surface of the workpiece 11. As a result, the space between the outer peripheral area 11c of the workpiece 11 and the outer peripheral suction area 6c is sealed, and leakage of negative pressure acting on the outer peripheral suction area 6c is prevented.

  In addition, after the workpiece 11 and the second elastic seal member 16 are in contact with each other, the second valve 12b may be opened to apply the negative pressure of the suction source 10 to the outer peripheral suction region 6c. When the warp of the work piece 11 is small, when the central area 11b of the work piece 11 is held by the central suction area 6b (see FIG. 4), the area between the outer peripheral area 11c and the outer peripheral suction area 6c is reduced. The space may be sealed.

  Then, when the transport unit 20 is further lowered, the outer peripheral area 11c of the workpiece 11 comes into contact with the outer peripheral suction area 6c, and is suction-held along the outer peripheral suction area 6c. Further, the second elastic seal member 16 is pressed by the outer peripheral suction area 6c to be deformed, and is embedded in the second groove 6g.

  FIG. 5 is a partial cross-sectional front view showing a state in which the outer peripheral area 11c of the workpiece 11 is held by the outer peripheral suction area 6c of the chuck table 4. As shown in FIG. 5, the outer peripheral region 11c of the workpiece 11 is held along the flat outer peripheral suction region 6c. As a result, the entire workpiece 11 is sucked and held by the holding surface 6a of the chuck table 4, and the warp of the workpiece 11 is corrected.

  When the outer peripheral area 11c of the workpiece 11 is pressed against the outer peripheral suction area 6c, the suction pad 34 is in contact with the workpiece 11, but the suction pad 34 receives an upward force from the workpiece 11. Then, the suction pad 34 moves in a direction approaching the main body 22 (upward). Therefore, the pressing of the workpiece 11 by the pressing portion 36 is not obstructed by the suction portion 26.

  For example, the pressing portion 36 presses the workpiece 11 until the outer peripheral region 11c comes into close contact with the outer peripheral region 11c (see FIG. 5). Therefore, the suction portion 26 can arrange the suction surface 34a of the suction pad 34 from a position below the pressing surface 36a (see FIG. 3) to the same height as the pressing surface 36a or a position above the pressing surface 36a. It is preferable to be configured as follows.

  As a result, the pressing portion 36 can be reliably brought into contact with the workpiece 11 until the workpiece 11 is held by the chuck table 4, and the workpiece 11 can be appropriately pressed against the holding surface 6a. The movement range of the suction pad 34 can be adjusted by the length of the rod member 30, the hardness (spring constant) of the spring member 32, and the like.

  After that, the negative pressure acting on the suction surface 34a of the suction pad 34 is released, and the transport unit 20 is raised. At this time, the pressing of the work piece 11 by the pressing portion 36 is also released, but since the work piece 11 is sucked by the central suction area 6b and the outer circumference suction area 6c, the warp of the work piece 11 is corrected. The state is maintained. In this way, the workpiece 11 is transported onto the chuck table 4 by the transport unit 20.

  According to the above method, first, the central region 11b of the workpiece 11 is sucked by the central suction region 6b to reduce the warp of the workpiece 11, and then the outer peripheral region 11c of the workpiece 11 is pressed by the pressing portion 36. And is sucked by the outer peripheral suction area 6c. In this way, by reducing the warp of the workpiece 11 before the outer peripheral region 11c is pressed by the pressing portion 36, the load on the transport unit 20 when the pressing portion 36 presses the workpiece 11 can be reduced. .

  As described above, the chuck table 4 according to the present embodiment includes the holding surface 6a that holds the workpiece 11, and the holding surface 6a includes the central suction area 6b that sucks the central area 11b of the workpiece 11 and the holding surface 6a. An outer peripheral suction area 6c for sucking the outer peripheral area 11c of the workpiece 11 is provided. Then, for example, the chuck table 4 sucks the central region 11b in the central suction region 6b to alleviate the warp of the workpiece 11, and then sucks the outer peripheral region 11c in the outer circumferential suction region 6c to remove the workpiece 11 from the workpiece 11. It is held by the holding surface 6a.

  When the workpiece 11 is sucked by the chuck table 4 in this manner, the workpiece 11 is deformed along the holding surface 6a, and the warp of the workpiece 11 is corrected. Therefore, the negative pressure can be prevented from leaking from the gap between the workpiece 11 and the holding surface 6a, and the workpiece 11 can be appropriately held.

  When the chuck table 4 is used, the workpiece 11 having a warp can be held without performing an operation such as sticking an adhesive tape having a size that covers the holding surface 6a to the back surface of the workpiece 11. Therefore, the workpiece 11 having a warp can be easily held without increasing the labor and cost required to hold the workpiece 11.

  The structures, methods, and the like according to the above-described embodiments can be appropriately modified and implemented without departing from the scope of the object of the present invention.

11 Workpiece 11a Device Region 11b Central Region 11c Peripheral Region 13 Substrate 13a Front Surface 13b Backside 15 Resin Layer (Mold Resin)
17 division line (street)
19 marker 21 electrode 2 processing device 4 chuck table 6 holding part 6a holding surface 6b central suction area 6c outer circumference suction area 6d first suction path 6e second suction path 6f first groove 6g second groove 8a first communication path 8b second Communication path 10 Suction source 12a First valve 12b Second valve 14 First elastic seal member 16 Second elastic seal member 20 Transport unit 22 Main body section 24 Transport arm 26 Suction section 28 Connection section 30 Rod member 32 Spring member 34 Adsorption pad 34a Suction surface 36 Pressing portion 36a Pressing surface

Claims (4)

A chuck table for holding a plate-shaped workpiece,
A holding part having a holding surface for holding the workpiece by suction, and a first suction path and a second suction path connected to the holding surface and a suction source for generating a suction force;
A first elastic seal member and a second elastic seal member provided on the holding surface,
The holding surface includes a central suction area that sucks the central area of the workpiece, and an outer peripheral suction area that surrounds the central suction area and sucks the outer peripheral area of the workpiece.
One end side of the first suction path is connected to the central suction area,
One end side of the second suction passage is connected to the outer circumference suction region,
The first elastic seal member is arranged so as to surround the central suction area and have an upper end protruding from the holding surface to come into contact with the workpiece.
The chuck table, wherein the second elastic seal member surrounds the outer peripheral suction area and is arranged so that an upper end thereof projects from the holding surface and comes into contact with the workpiece.   The chuck table according to claim 1, wherein the first elastic seal member and the second elastic seal member are configured by tubes made of resin. The other end side of the first suction passage is connected to the suction source via a first communication passage provided with a first valve,
The chuck table according to claim 1 or 2, wherein the other end of the second suction passage is connected to the suction source via a second communication passage having a second valve. A chuck table according to any one of claims 1 to 3,
A processing unit for processing the workpiece held by the chuck table;
A processing apparatus comprising: a transfer unit that transfers the workpiece,
The transport unit includes a main body portion, a suction portion that includes a suction pad that holds the workpiece by a suction surface and is connected to the main body portion, and the workpiece that faces the holding surface of the chuck table. A pressing portion having a pressing surface for pressing and connected to the main body,
The suction portion is configured such that the suction surface of the suction pad can be arranged from a position below the pressing surface to a position at the same height as the pressing surface or a position above the pressing surface. Processing equipment.