JP2014150206A - Conveyance device of plate-like material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conveyance device of a plate-like material which can vacuum fixing even a warped wafer, by conveying the wafer in non-contact state and pressing the wafer against a chuck table.SOLUTION: In a conveyance device of a plate-like material including suction holding means for suction holding a plate-like material, and moving means for moving the suction holding means from a predetermined position to a holding table, the suction holding means has a support base coupled to the moving means, a non-contact suction holder disposed on the lower surface of the support base, and a fluid ejector disposed on the lower surface of the support base. When the suction force by the non-contact suction holder is released for the plate-like material conveyed to the holding table, fluid is ejected from the ejection port of the fluid ejector facing the plate-like material, and warpage of the workpiece is corrected by the pressing force of the fluid.

Description

  The present invention relates to a plate-like material conveying apparatus that holds and conveys various plate-like materials.

  For example, in a semiconductor device manufacturing process, devices such as IC and LSI are formed in each region partitioned by division lines (streets) formed in a lattice shape on the surface of a semiconductor wafer having a substantially disk shape, Individual device chips are manufactured by dividing a region in which devices are formed along a predetermined division line.

  As a dividing device that divides a semiconductor wafer into individual devices, a cutting device called a dicing device is generally used. This cutting device uses a cutting blade of a very thin cutting edge to divide the semiconductor wafer along a planned dividing line. To cut. The devices thus divided are packaged and widely used in various electric devices such as mobile phones and personal computers.

  When dicing a semiconductor wafer, the semiconductor wafer is attached to a dicing tape whose outer peripheral portion is attached to an annular frame, and the semiconductor wafer is divided into individual devices while being supported by the annular frame via the dicing tape. .

  However, in recent years, in order to achieve weight reduction and downsizing of electrical equipment, a splitting technique called a so-called dicing method has been developed and put into practical use as a technique for splitting a wafer with a thinner thickness, for example, about 50 μm. (For example, refer to Japanese Patent Laid-Open No. 11-40520).

  This tip dicing method is a semiconductor in which a dividing groove having a predetermined depth (a depth corresponding to the finished thickness of the device) is formed along the line to be divided from the surface of the semiconductor wafer, and then the dividing groove is formed on the surface. This is a technique in which the back surface of a wafer is ground and a dividing groove is exposed on the back surface to divide the wafer into individual devices. The thickness of the device can be processed to about 50 μm.

  In this tip dicing method, the wafer is conveyed to the chuck table without being fixed to the annular frame, and the wafer is directly sucked and held by the chuck table. For transporting a wafer by the first dicing method, for example, a transport device that sucks and holds a semiconductor wafer in a non-contact manner using Bernoulli's principle (theorem) is used (see, for example, Japanese Patent Laid-Open No. 5-36816).

  Generally, a chamfered portion having an arc surface extending from the front surface to the back surface is formed on the outer periphery of the wafer. Therefore, if the wafer is thinned by grinding the backside of the wafer, the knife edge formed by the arc surface and the ground surface remains in the chamfered part, which is dangerous and the outer periphery is chipped, resulting in a deterioration in device quality. I will let you.

  Japanese Patent Application Laid-Open No. 2000-173961 discloses a so-called edge trimming method, that is, a peripheral processing method for removing a chamfered portion of a wafer with a cutting blade before grinding the back surface of the wafer.

  Usually, it is a transfer device that uses Bernoulli's principle, which is often used in the tip dicing method, but this edge trimming technique is also used for the same reason of omitting fixing to an annular frame that is unnecessary for subsequent back surface grinding. Has come to be.

JP 11-40520 A JP-A-5-36816 JP 2000-173961 A

  There are various types of wafers that use the edge trimming method to remove the chamfered portion of the wafer with a cutting blade, and some of them are ground to some extent or warped because other materials are laminated. There is also a wafer.

  In that case, even if the warped wafer can be transported, when placing it on the chuck table at the transport destination, in the case of the transport device using the Bernoulli principle, the non-contact principle is the principle, so the wafer is pressed against the chuck table. Therefore, a negative pressure leak occurs due to the warp of the wafer, which causes a problem that the wafer cannot be vacuum-adsorbed by the chuck table.

  The present invention has been made in view of such points, and the object of the present invention is to provide a plate-like object that can be conveyed in a non-contact state even on a warped wafer and pressed against a chuck table to be vacuum fixed. It is to provide a transport device.

  According to the present invention, there is provided a plate-like object conveying apparatus comprising: suction holding means for sucking and holding a plate-like object; and moving means for moving the suction holding means from a predetermined position to a holding table, The suction holding means includes a support base coupled to the moving means, a non-contact type suction holder disposed on the lower surface of the support base, and a fluid ejector disposed on the lower surface of the support base. When the suction force by the non-contact type suction holder is released with respect to the plate-like object conveyed to the holding table, the fluid is ejected from the outlet of the fluid ejector facing the plate-like object. A plate-like object conveying apparatus is provided in which warpage of the workpiece is corrected by the pressing force of the fluid.

  According to the transport device of the present invention, the non-contact suction holder using the Bernoulli principle is provided, and the fluid ejector that jets the fluid onto the plate-like object and presses the suction holding means in a non-contact manner is provided. Even a warped wafer can be conveyed in a non-contact state and pressed against the suction holding means to be vacuum fixed.

  In the invention according to claim 2, since the fluid ejector is provided at each of the positions corresponding to the central region and the outer peripheral region of the workpiece, it can correspond to either the direction of the convex warp or the concave warp, The wafer can be straightened.

It is a perspective view of the conveyance apparatus which concerns on this invention embodiment. It is the figure which looked at the support base from the lower surface. It is sectional drawing of a non-contact-type suction holder. It is the sectional view on the AA line of FIG. 2 during wafer conveyance shown with the chuck table. It is the sectional view on the AA line of FIG. 2 of the first half part which mounts a wafer on a chuck table. It is the sectional view on the AA line of FIG. 2 of the latter half part which mounts a wafer on a chuck table. FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2 when the mounting is completed and the wafer is sucked with a negative pressure by the chuck table. FIG. 3 is a cross-sectional view taken along the line B-B in FIG. 2 for flatly correcting the wafer along the middle convex. It is the BB sectional drawing of FIG. 2 which correct | amends the wafer along a hollow center flatly.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1, a perspective view of a transfer device 2 according to an embodiment of the present invention is shown. The transport device 2 includes a base unit 4, a rotating member 6 that is rotated in the direction of arrow R by a motor built in the base unit 4, and driving of an air cylinder or the like that is mounted on the rotating member 6 and built in the rotating member 6 And a vertically moving member that can be moved in the arrow Z direction (vertical direction) by means. The rotating member 6 and the vertically moving member 8 constitute the moving means 5.

  An arm 10 is fixed to the side surface of the tip of the vertical movement member 8. A suction holding means 15 is attached to the tip of the arm 10. The suction holding means 15 includes a support base 12. As best shown in FIG. 2, the support base 12 includes an annular member 12a and a linear member 12b.

  Three non-contact type suction holders 14 are arranged on the annular member 12a of the support base 12 so as to be separated from each other by 120 degrees in the circumferential direction. The non-contact type suction holder 14 is attached so as to protrude from the back surface of the annular member 12a (see FIG. 4). One non-contact type suction holder 14 is disposed so as to penetrate the arm 10 and the annular member 12a of the support base 12 and protrude from the back surface of the annular member 12a.

  A non-contact type suction holder 14a is attached to a substantially central portion of the annular member 12a of the support base 12 so as to penetrate the arm 10 and the linear member 12b and protrude from the linear member 12b.

  The non-contact suction holder 14 is connected to a pressurized fluid supply source 18 via an electromagnetic switching valve 20. For example, pressurized air is used as the pressurized fluid. Similarly, the non-contact suction holder 14 a is connected to the pressurized fluid supply source 18 via the electromagnetic switching valve 22.

  Further, three fluid ejectors 16 are disposed on the annular member 12a of the support base 12 so as to be spaced apart from each other by 120 degrees in the circumferential direction. Each fluid ejector 16 penetrates the annular member 12a and protrudes from the back surface of the annular member 12a. These fluid ejectors 16 are connected to a fluid supply source 18 via an electromagnetic flow rate adjusting valve 24.

  A fluid ejector 16a is attached so as to penetrate the arm 10 and the linear member 12b of the support base 12 and protrude from the back surface of the linear member 12b. The fluid ejector 16 a is connected to the fluid supply source 18 via the electromagnetic flow rate adjustment valve 26.

  Referring to FIG. 3, a longitudinal sectional view of the non-contact suction holder 14 is shown. The non-contact type suction holder 14 is a suction holder using the Bernoulli principle. A fluid supply path 30 connected to the fluid supply source 18 is formed in the main body 28 of the non-contact suction holder 14, and the fluid supply path 30 is an annular fluid supply path defined by the main body 28 and a vertical member 32. 34. The vertical member 32 is formed integrally with the disc-like horizontal member 32a, and an annular orifice 36 is formed between the main body 28 and the disc-like horizontal member 32a.

  Pressurized fluid such as pressurized air supplied from the fluid supply source 18 is introduced into the fluid supply path 30 of the non-contact type suction holder 14 as indicated by an arrow 38, and then from the fluid supply path 30 to the annular fluid supply path 34. Accelerated through the incoming annular orifice 36, fluid is ejected at high speed as indicated by arrow 40.

  As a result, a suction force is generated as indicated by an arrow 42 in the central portion surrounded by the fluid 40 ejected by Bernoulli's theorem. The non-contact type suction holder 14 of the present embodiment generates a suction force according to the Bernoulli principle, and sucks and holds a workpiece such as a wafer in a non-contact manner by this suction force.

  Next, with reference to FIG. 4 to FIG. 7, the operation of the transport device 2 that transports the wafer 11 by the transport device 2 according to the embodiment of the present invention and places the wafer 11 on the chuck table 44 will be described. Referring to FIG. 4, there is shown a cross-sectional view taken along the line AA of FIG. 2 together with the chuck table 44 during wafer transfer.

  The chuck table 44 includes a frame body 46 formed of a metal such as SUS and a suction holding portion 48 formed of a porous member such as porous ceramics fitted to the frame body 46. The suction path 50 formed in the frame 46 is connected to a vacuum suction source (not shown).

  During the wafer transfer, the electromagnetic switching valves 20 and 22 are switched to the connected state, and the wafer 11 is sucked and held by the non-contact suction holders 14 and 14a. At this time, the electromagnetic flow rate adjusting valve 24 is maintained in a shut-off state. Therefore, the fluid ejector 16 is in a stopped state.

  In FIG. 4, the suction holding means 15 is lowered as indicated by the arrow, and the wafer 11 is placed on the chuck table 44 as shown in FIG. After the wafer 11 is placed on the chuck table 44, the suction force of the non-contact suction holders 14 and 14a is released as shown in FIG.

  At the same time, pressurized fluid is ejected from the ejection port of the fluid ejector 16 facing the wafer 11 to correct the warpage of the wafer 11 by the pressing force of the fluid, and the chuck table 44 is negatively pressurized as indicated by an arrow A. The wafer 11 is sucked and held by the chuck table 44 by suction.

  As shown in FIG. 7, the suction holding means 15 after the placement of the wafer 11 is retracted from the chuck table 44 and continues the suction holding by the chuck table 44 of the wafer 11.

  Referring to FIG. 8, a cross-sectional view taken along the line BB of FIG. 2 showing a correction state of the warpage of the wafer 11A warped in a middle convex shape is shown. In this case, in order to correct the warp, the pressurized fluid is ejected from the ejection ports of the fluid ejectors 16 and 16a facing the wafer 11A.

  Since the center of the wafer 11A is warped in the middle, the amount of the ejected fluid ejected from the fluid ejector 16a as shown by the arrow 52 is larger than the amount of the ejected fluid ejected from the fluid ejector 16 shown by the arrow 54. Do more.

  As a result, a large pressing force acts on the wafer 11A in the central portion, so that the wafer 11A is warped and held on the chuck table 44 as indicated by a two-dot chain line. Although not specifically shown, after the wafer 11A is placed on the chuck table 44, the suction force of the non-contact suction holders 14 and 14a is released.

  Referring to FIG. 9, there is shown a cross-sectional view taken along the line BB of FIG. 2 showing a correction state of the warpage of the wafer 11B warped in the center concave shape. In this case, the ejection amount from the fluid ejector 16 facing the outer peripheral portion of the wafer 11B is increased as indicated by an arrow 56, and the ejection amount of the fluid ejector 16a disposed in the central portion is indicated by an arrow 58. So less.

  As a result, a large pressing force acts on the outer peripheral portion of the wafer 11 </ b> B, and the warpage of the wafer 11 </ b> B is corrected as indicated by a two-dot chain line, and is sucked and held on the chuck table 44. Also in this case, although not particularly shown, after the wafer 11B is placed on the chuck table 44, the suction force of the non-contact suction holders 14 and 14a is released.

  In the above-described embodiment, the case where the wafer 11 is transferred by the transfer device of the present invention has been described. However, the transfer object is not limited to the wafer 11, and the present invention can be applied to plate-like objects such as a ceramic substrate and a glass substrate. The conveying device of the invention can be similarly applied.

2 Conveying device 5 Moving means 10 Arm 12 Support base 14, 14a Non-contact suction holder 15 Suction holding means 16, 16a Fluid ejector 18 Fluid supply source 20, 22 Electromagnetic switching valve 24, 26 Electromagnetic flow control valve 36 Annular Orifice 42 Suction force 44 Chuck table 11 Wafer 11A Wafer 11B warped in a middle convex shape Wafer 11B warped in a middle concave shape

Claims (2)

A plate-like object conveying apparatus comprising: a suction holding means for sucking and holding a plate-like object; and a moving means for moving the suction holding means from a predetermined position to a holding table,
The suction holding means includes
A support base coupled to the moving means;
A non-contact suction holder disposed on the lower surface of the support base;
A fluid ejector disposed on the lower surface of the support base,
When releasing the suction force by the non-contact type suction holder to the plate-like object conveyed to the holding table, the fluid is ejected from the outlet of the fluid ejector facing the plate-like object, and the fluid A plate-like object conveying apparatus, wherein the workpiece is warped with a pressing force of.   The plate-like article transport device according to claim 1, wherein the fluid ejector is disposed at a position corresponding to a central area and an outer peripheral area of the workpiece.

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