JP2019072776A - Holding method for plate-like object - Google Patents

Abstract

To more securely suck and hold a warped plate-like object by use of holding means.SOLUTION: A holding method comprises: a liquid supply step in which a liquid L is supplied onto a holding surface 700a of holding means 70 having: the holding surface 700a for holding a warped plate-like object W; a suction hole that opens in the holding surface 700a; and a suction path 70B that selectively allows communication of the suction hole with suction means 76; a placing step in which the warped plate-like object W is placed onto the holding surface 700a via the liquid L; and a suction holding step in which, after the placing step, the plate-like object W is held on the holding surface 700a by allowing communication of the suction hole with the suction means 76 and sucking the plate-like object W together with the liquid L.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a method for holding a warped plate.

  A package substrate configured by sealing a plurality of device chips stacked on a substrate with a resin may have a warp due to the influence of heat at the time of resin sealing. Even if it is attempted to suction and hold the holding substrate with a plate substrate such as a package substrate having such a warp, the suction force leaks from the portion where the plate member and the holding surface of the holding table are not in contact and can be held. There is a problem of not being.

  In order to solve the above-mentioned problems, a method is proposed in which a plate-like object having a warp is heated while being pressed on a holding table to correct the warp and then suction-held by the holding table (for example, see Patent Document 1) There is.

JP, 2011-192781, A

  However, there is also a plate-like object whose warping is not eliminated by pressing and heating, and there is a problem that even a plate-like object having such a warp can be reliably suctioned and held by the holding table.

  The present invention for solving the above-mentioned problems is a method for holding a plate-like object having a warp, which comprises a holding surface for holding the plate-like object, a suction hole opened in the holding surface, and suction of the suction hole. A liquid supply step of supplying a liquid onto the holding surface of the holding means having a suction path selectively communicating with the means, and placing a plate having a warp on the holding surface through the liquid And a suction holding step for suctioning the plate-like object together with the liquid and holding the plate-like object on the holding surface after the mounting step is performed and the suction hole is communicated with the suction means. It is a holding method.

  It is preferable to further include a carrying-in step of carrying the plate-like object onto the holding surface such that the center of the plate-like object coincides with the center of the holding surface before performing the placing step.

  The holding method according to the present invention comprises a holding surface for holding a plate-like object, a suction hole opened in the holding surface, and a suction passage having suction paths for selectively communicating the suction holes with the suction means. After performing the liquid supply step of supplying the liquid to the liquid, the mounting step of mounting the plate having a warp on the holding surface through the liquid, and the mounting step, the suction holes are communicated with the suction means And a suction holding step of suctioning the plate-like object together with the liquid and holding it on the holding surface, the liquid intervenes in a place where the holding surface and the plate-like object are not in contact when performing suction holding. Since it plays a role as a seal, the negative pressure (suction force) does not leak, and it becomes possible to reliably suction and hold even a plate having warpage on the holding surface.

  Further, before carrying out the mounting step, the plate-like object is further provided with a carrying-in step of carrying the plate-like object onto the holding surface such that the center of the plate-like object coincides with the center of the holding surface. Can be held by suction at an appropriate position on the holding surface.

It is a perspective view showing an example of a grinding device. It is sectional drawing which shows an example of the holding means to carry out suction holding of the plate-like article which had curvature. It is sectional drawing which shows an example of the plate-shaped article which had curvature. It is sectional drawing which shows the state which is supplying the liquid on the holding surface of a holding means. It is sectional drawing which shows the state which has carried the plate-like object on the holding surface so that the center of a plate-like object may be in agreement with the center of the holding surface of a holding means. It is sectional drawing which shows the state which mounted the plate-shaped article which had curvature on the holding surface of a holding means via liquid. It is sectional drawing which shows the state which attracts | sucks a plate-like thing with a liquid, and is hold | maintained by the holding surface of a holding means.

The grinding apparatus 1 shown in FIG. 1 is an apparatus for grinding a plate-like object W having a warp held on a chuck table 30 by a grinding means 4. The plate-like object W is attached to and detached from the chuck table 30 on the front side (-Y direction side) on the base 1A of the grinding apparatus 1, and the chucking table 30 by the grinding means 4 on the rear side (+ Y direction side) on the base 1A. Grinding of the plate-like object W held on top is performed.
On the front side of the base 1A, input means 19 for an operator to input processing conditions and the like to the grinding apparatus 1 is disposed.

  On the front side of the base 1A, a first cassette 11 for accommodating the plate-like object W before grinding and a second cassette 12 for accommodating the plate-like object W after grinding are disposed. Between the first cassette 11 and the second cassette 12, the plate W before grinding is unloaded from the first cassette 11 and the plate W after grinding is loaded into the second cassette 12. The robot 10 is disposed. In the movable area of the robot 10, alignment means 13 for aligning the plate-like object W before grinding to a predetermined position and cleaning means 7 for cleaning the plate-like object W after grinding are disposed.

  A first transport means 31 is disposed in the vicinity of the alignment means 13, and a second transport means 32 is disposed in the vicinity of the cleaning means 7. The first conveying means 31 conveys the plate-like object W placed on the alignment means 13 to the chuck table 30, and the second conveying means 32 is a ground plate-like object held by the chuck table 30. The W is transported to the cleaning means 7.

  The second transport means 32 has, for example, a suction pad 320 having a disk-like outer shape and holding the plate-like object W by suction on its lower surface (suction surface), and extends horizontally in the suction direction. And an arm moving means 322 which is connected to the arm 321 and which horizontally pivots the arm 321 around an axis in the Z axis direction and vertically moves the arm 321 in the Z axis direction.

  The chuck table 30 has, for example, a circular outer shape, and sucks and holds the plate-like object W on a holding surface 30 a made of a porous member or the like. The chuck table 30 is surrounded by a cover 33, is rotatable around an axis in the Z-axis direction, and is disposed below the bellows 33a connected to the cover 33 and the cover 33 (not shown). Reciprocation movement in the Y-axis direction is possible by the Y-axis direction feeding means. On both sides of the movement path of the chuck table 30, a concave grinding water containing portion 34 is formed which receives grinding water flowing down from above the cover 33.

  A column 1B is erected on the rear side on the base 1A, and a grinding feed means 35 for grinding and feeding the grinding means 4 in the Z-axis direction is disposed on the side of the column 1B. The grinding feed means 35 holds a ball screw 350 having a vertical axial center, a pair of guide rails 351 arranged parallel to the ball screw 350, a motor 352 for rotating the ball screw 350, and the grinding means 4 The nut is screwed into the ball screw 350 and the elevating holder 353 whose side is in sliding contact with the guide rail 351. As the motor 352 rotates the ball screw 350, the elevation holder 353 is guided by the guide rail 351 to ascend and descend, and the grinding means 4 supported by the elevation holder 353 also ascends and descends.

  The grinding means 4 has a spindle 40 having an axis in the Z-axis direction, a housing 41 for rotatably supporting the spindle 40, a motor (not shown) for rotationally driving the spindle 40, and a circular shape connected to the lower end of the spindle 40 And a grinding wheel 44 detachably connected to the lower surface of the mount 43. The grinding wheel 44 is one in which a plurality of grinding wheels are annularly disposed on the bottom surface of an annular wheel base.

  The cleaning means 7 shown in FIG. 1 is a sheet-fed spinner cleaning apparatus, and includes holding means 70 for sucking and holding the plate-like object W, a container portion 71 formed on the base 1A and in which the holding means 70 is accommodated. A rotating means 72 for rotating the means 70 around the Z axis direction, a nozzle 73 for supplying a cleaning liquid (for example, pure water) to the plate-like object W held by the holding means 70; And a cover 74 for preventing the

  The outer shape of the container portion 71 is formed, for example, in a polygonal shape, and a drain port (not shown) is formed at the bottom of the container portion 71. The nozzle 73 communicating with a liquid supply source (not shown) and supplying the liquid to the plate-like object W is, for example, erected in the container portion 71, and is opened in the −Z direction side and has a jet port Have. The nozzle 73 can pivot around an axis in the Z-axis direction, and the injection port can move from above the holding means 70 to the retracted position.

  As shown in FIG. 2, the holding means 70 includes, for example, a spinner table 70A whose outer shape is formed in a circle smaller in diameter than the plate-like object W, and the spinner table 70A adsorbs the plate-like object W. An adsorption unit 700 formed of a porous member or the like, and a frame 701 supporting the adsorption unit 700 are provided. A fine suction hole (not shown) is opened in the holding surface 700a which is the exposed surface of the suction portion 700 and flush with the upper surface of the frame 701, and the spinner table 70A sucks the plate W by the holding surface 700a. Can be held.

A suction space 702 extends between the lower surface of the suction portion 700 and the bottom of the frame 701, and a suction pipe 703 passing through the bottom of the frame 701 is in communication with the suction space 702. A suction means 76 is connected to the suction pipe 703.
In the suction pipe 703, for example, a separator 704 for separating liquid from air flowing in the suction pipe 703, and a check valve 705 are disposed. The check valve 705 is mounted in the suction pipe 703 in a direction that does not allow the flow of air in the direction toward the holding means 70. The suction passage 70B is formed by the suction space 702, the suction pipe 703, the separator 704, and the check valve 705, and the suction passage 70B selectively selects a suction hole (not shown) and suction means 76 opened in the holding surface 700a. It communicates with

The suction means 76 includes, for example, an air supply source 760 which is made of a compressor, an air storage tank or the like and can supply compressed air, and a pipe 761 for communicating between the air supply source 760 and an ejector 763 described later. The on-off valve 762 disposed in the pipe 761, an ejector 763 for generating a negative pressure by the flow of air supplied from the air supply source 760, an exhaust port 764 for exhausting air, an ejector 763 and an exhaust port 764 And a pipe 765 for communicating the two.
The on-off valve 762 is, for example, a spring return normally closed solenoid valve having a single acting solenoid, but is not limited thereto.
The downstream side of the suction pipe 703 is connected substantially perpendicularly to the ejector 763.

Below, the case where plate-like object W is ground using grinding device 1 shown in Drawing 1 is explained.
The plate-like object W shown in FIGS. 1 and 3 includes, for example, a circular wafer W1 made of a silicon base material or the like, and a metal W is used on the surface W1a (see FIG. 3) of the wafer W1 on which devices not shown are formed. Alternatively, a film W2 of uniform thickness made of resin is laminated. The exposed surface of the wafer W1 is the back surface W1b of the plate-like object W. The plate-like object W is entirely convexly curved in a convex shape, that is, has warpage, due to thermal effects (such as contraction of the film W2) at the time of formation of the film W2. In addition, when the plate-like object W is placed on the holding surface 700 a of the holding means 70, the medium-convex-shaped warpage is like a pile of the plate-like object W on the holding surface 700 a, that is, a plate-like object The warpage is such that the back surface W1b of W gradually increases from the area on the outer peripheral side toward the area in the center. Further, on the exposed surface of the film W2, a protective tape T is attached which protects a device (not shown) from the grinding pressure at the time of grinding.
The plate-like object W is not limited to the film laminated wafer in which the film W2 as described above is laminated on the wafer W1. For example, a rewiring layer or an electrode in the state of a WL-CSP wafer, that is, a wafer The wafer may be formed, sealed on the surface of the wafer with a resin, and divided into each package chip by a cutting blade or the like. Alternatively, it may be a wafer having a warp such as a laminated wafer or a package substrate in which wafers are joined together by bonding a plurality of wafers with an adhesive layer made of resin or the like.

  First, in the attachment / removal region shown in FIG. 1, the plate-like object W is placed on the holding surface 30a of the chuck table 30 such that the back surface W1b is on the upper side. Then, the suction force generated by a suction source (not shown) is transmitted to the holding surface 30a, whereby the chuck table 30 suctions and holds the plate-like material W on the holding surface 30a.

  Next, the chuck table 30 holding the plate-like object W moves in the + Y direction from the mounting and demounting area to below the grinding means 4 in the grinding area. Further, a motor (not shown) rotationally drives the spindle 40, and the grinding wheel 44 also rotates accordingly. The grinding means 4 is fed by the grinding feed means 35 in the −Z direction, and the grinding wheel of the rotating grinding wheel 44 abuts on the back surface W1 b of the plate-like object W, whereby grinding is performed. During grinding, the plate-like object W also rotates as the chuck table 30 rotates, so the entire back surface W1b of the plate-like object W is ground.

  After the plate-like object W is ground to a predetermined thickness and the grinding wheel 44 is separated from the plate-like object W, the chuck table 30 for sucking and holding the plate-like object W is sent in the -Y direction, and the second conveying means It is located near 32. The arm moving means 322 moves the suction pad 320 onto the plate W, and then lowers the suction pad 320 to bring it into contact with the plate W, and the plate W is adsorbed and held by the suction pad 320. In addition, the center of the suction surface of the suction pad 320 and the center of the plate-like object W are substantially in agreement. Then, the second transport means 32 transports the plate-like material W to the cleaning means 7.

  The cleaning means 7 is set so that the plate-like object W having a warp can be reliably suctioned and held by the holding means 70 before the plate-like object W is transported. That is, the holding method of the plate-like object W which concerns on this invention demonstrated below is implemented.

(1) Liquid Supply Step First, as shown in FIG. 4, the liquid L is supplied onto the holding surface 700 a of the holding means 70. That is, for example, the nozzle 73 pivots, and the injection port is positioned above the center of the spinner table 70A. Then, an appropriate amount of liquid L (pure water) is dropped from the nozzle 73 toward the holding surface 700a of the spinner table 70A. When the liquid L is deposited on the holding surface 700a by a predetermined amount by surface tension, the nozzle 73 stops the supply of the liquid L and retracts from above the spinner table 70A.
In addition, a liquid supply step is not limited to the example in this embodiment. For example, the liquid supply source may be communicated with the suction passage 70B of the holding means 70, and the liquid may be supplied from the suction passage 70B onto the holding surface 700a.

(2) Loading Step Next, as shown in FIG. 5, the arm moving means 322 pivotally moves the arm 321, and the suction pad 320 holding the plate-like object W by suction holds the center of the suction surface of the spinner table 70A. It is positioned above the plate W so as to substantially coincide with the center of the holding surface 700a. The plate-like object W is adsorbed and held by the suction pad 320 in a state in which the center thereof substantially coincides with the center of the suction surface of the suction pad 320, the plate-like object W has its center at the holding surface 700 a of the holding means 70. Is brought in on the holding surface 700a so as to coincide with the center of the.
In addition, you may implement the mounting step mentioned later, without implementing this carrying-in step.

  In the present embodiment, the carry-in step is performed after the liquid supply step is performed as described above, but the carry-in step may be performed before the liquid supply step is performed. In this case, in the liquid supply step, the liquid L is jetted and supplied from the side of the holding surface 700 a so as to draw, for example, a parabola to the holding surface 700 a of the holding means 70.

(3) Mounting Step Next, the suction pad 320 is lowered in the -Z direction, and the protective tape T stuck to the film W2 of the plate-like object W and the holding surface 700a of the holding means 70 Contact through. In this state, since the plate-like object W has a convex convex shape, assuming that the liquid L is not on the holding surface 700a, a suction force is applied between the protective tape T and the holding surface 700a. There may be gaps to leak. However, in the holding method according to the present invention, the plate-like object W is placed on the holding surface 700a as shown in FIG. 6 in a state where the gap is closed by the liquid L deposited on the holding surface 700a. Be placed. Then, the suction of the plate-like object W by the suction pad 320 is released, and the suction pad 320 is separated from the plate-like object W.
Depending on the degree of warpage of the plate-like object W, the plate-like object W is placed on the holding surface 700a of the holding means 70 so as to be concaved, that is, the state in which the plate-like object W is shown in FIG. It may be placed on the holding surface 700 a so as to be upside down.
Also, for example, when the warpage of the plate-like material W is such that the back surface W1b, which is the surface to be ground, is gradually lowered from the area on the outer peripheral side toward the center area (inward concave warpage) Even in such a case, the plate-like object W having the concaved concave shape may be placed on the holding surface 700a of the holding means 70 such that the back surface W1b is on the upper side.
Furthermore, although it is preferable that the diameter of the holding surface 700a of the holding means 70 is smaller than the diameter of the plate W as in this embodiment, the diameter of the holding surface of the holding means is substantially equal to the diameter of the plate W It may be a size.

(4) Suction and holding step After the plate-like object W is placed on the holding surface 700 a of the holding means 70, the adsorption of the plate-like object W by the suction pad 320 is released or the adsorption is released. At the same time, the suction means 76 communicates with a suction hole (not shown) opened in the holding surface 700a to suck the plate-like material W together with the liquid L and hold it on the holding surface 700a. Specifically, first, as shown in FIG. 7, the on-off valve 762 is switched from the closed state to the open state. Then, compressed air is supplied from the air supply source 760 to the pipe 761, and the air passes through the on-off valve 762 and reaches the ejector 763.

  The ejector 763 is provided with a flow passage whose diameter is reduced inside, and the air reaching the ejector 763 flows through the flow passage reduced in this diameter and flows into the pipe 765, so that the ejector 763 A suction force is generated to suck air from the suction pipe 703 in the direction of the arrow R1. Then, the generated suction force is transmitted to a plurality of suction holes (not shown) opened in the holding surface 700a, whereby the plate-like object W is suctioned and held on the holding surface 700a. At this time, the gap between the protective tape T and the holding surface 700a is sealed by the liquid L on the holding surface 700a so that the plate-like object W can be reliably suctioned and held by the holding surface 700a. Be done. The air sucked from the suction pipe 703 is exhausted from the exhaust port 764 together with the air supplied from the air supply source 760.

  The liquid L deposited on the holding surface 700 a is drawn into the suction pipe 703 through the suction space 702 in parallel with the suction of the plate-like object W by the holding surface 700 a. When this liquid flows into the ejector 763, the suction force generated by the ejector 763 decreases, but since the separator 704 is provided in the middle of the suction pipe 703, the inside of the suction pipe 703 is separated by the separator 704. The separation of the liquid L from the passing air prevents a reduction in suction.

  As described above, in the holding method according to the present invention, the holding surface 700a for holding the plate-like object W, the suction hole (not shown) opened in the holding surface 700a, and the suction that selectively connects the suction hole to the suction means 76. A liquid supplying step of supplying the liquid L onto the holding surface 700a of the holding means 70 having the path 70B, and a mounting step of mounting the plate-like object W having a warp on the holding surface 700a via the liquid L And suction and holding steps for communicating the suction holes to the suction means 76 and performing suction and holding the plate-like object W together with the liquid L on the holding surface 700a after carrying out the mounting step; Since the liquid L intervenes in the portion where the holding surface 700a and the plate-like object W are not in contact and starts to function as a seal at the time when the start is started, the suction force does not leak and has a warp. Plate-like object W but holding surface 700 In can be held reliably sucked.

  Further, before carrying out the mounting step, the method further includes a carry-in step of carrying the plate-like object W onto the holding surface 700 a so that the center of the plate-like object W coincides with the center of the holding surface 700 a. Thus, the plate-like object W can be held by suction at an appropriate position on the holding surface 700a.

  The holding method according to the present invention is not limited to the above embodiment, and the configurations of the holding means 70 and the suction means 76 shown in the attached drawings are not limited to this, either. It can change suitably in the range which can exhibit the effect of invention.

  For example, the holding means used when carrying out the holding method according to the present invention is not limited to the holding means 70 disposed in the cleaning means 7, and a chuck for sucking and holding the plate-like object W at the time of grinding The table 30 may be used as a holding means. Further, in the present embodiment, the holding means 70 is disposed in the grinding apparatus 1, but not the grinding apparatus 1, but a cutting apparatus for cutting the sheet W with a rotating cutting blade, a laser beam is a sheet A holding means 70 is disposed in a laser processing apparatus for performing various processes by irradiating W or a cutting tool for turning a plate W, and the holding method according to the present invention is carried out in each of these apparatuses. It is good also as a thing.

  In the present embodiment, the holding means 70 is provided with the adsorption portion 700 made of a porous member or the like, and the fine pores of the adsorption portion 700 function as suction holes, but the form of the suction holes is limited thereto. It is not a thing. For example, the holding means may have a plurality of annular suction grooves formed concentrically on the holding surface, and these annular suction grooves may be configured to function as suction holes. Further, for example, in the case where the plate-like object to be suctioned and held is a rectangular warped package substrate and cutting is performed, the holding means has a blade relief groove formed on the holding surface thereof. A jig table may be provided, and suction holes may be respectively formed in the respective areas divided by the blade relief grooves.

1: Grinding apparatus 1A: Base 1B: Column 19: Input means 10: Robot 11: First cassette 12: Second cassette 13: Alignment means 30: Chuck table 30a: Holding surface
31: first conveying means 32: second conveying means 320: suction pad 321: arm 322: arm moving means 35: grinding feeding means 4: grinding means 7: washing means
70: Holding means
70A: Spinner table 700a: Holding surface 70B: Suction path 702: Suction space 703: Suction pipe 704: Separator 705: Check valve 71: Container section 72: Rotating means 73: Nozzle 74: Cover 76: Suction means 760: Air Supply source 761: Piping 762: On-off valve 763: Ejector 764: Drain 765: Piping W: Plate W1: Wafer W2: Membrane T: Protective tape

Claims (2)

It is a holding method of the plate-like object which had curvature, and
A liquid is supplied onto the holding surface of a holding means having a holding surface for holding a plate-like object, a suction hole opened in the holding surface, and a suction passage selectively communicating the suction hole with the suction means. A liquid supply step,
Placing a plate having a warp on the holding surface via the liquid;
A suction holding step of communicating the suction hole to the suction means after the mounting step, and sucking and holding the plate-like material together with the liquid on the holding surface.   2. The method according to claim 1, further comprising a loading step of loading the plate onto the holding surface such that the center of the plate coincides with the center of the holding surface before performing the placing step. How to hold.

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