JP2019133979A - Transfer mechanism - Google Patents

Abstract

To ensure that a holding claw enters between the lower surface of a wafer and a holding surface in a transport mechanism that holds the outer periphery of the wafer by causing the holding claw to enter between the lower surface of the wafer and the holding surface.SOLUTION: Air is ejected from an air nozzle 8 to float a plate-like workpiece W from the holding surface of a holding table 9, and a guide column 6 is brought into contact with the outer peripheral edge Wd of the plate-like workpiece W by moving a movable support portion 4 toward the center of the plate-like workpiece W by advancing and retreating means 5, the movable support portion 4 is moved in the same direction, and the holding claw 7 is caused to enter between the lower surface Wb of the plate workpiece W and the holding surface of the holding table 9 to hold the workpiece W.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a transfer mechanism that holds and transfers an outer peripheral edge of a wafer.

  In a processing apparatus that cuts or grinds a wafer, for example, when the back side where no device is formed cannot be sucked and held, an edge clamp type transport mechanism that holds the outer periphery of the wafer is used.

  The edge clamp type transport mechanism includes at least three holding claws, and the holding claws are moved between the holding surface of the table holding the wafer and the lower surface of the wafer by moving the holding claws toward the center in the radial direction of the wafer. And the outer peripheral edge of the wafer is held (see, for example, Patent Document 1). In addition, when a holding claw enters between the holding surface and the lower surface of the wafer, air is blown from the holding surface to float the wafer.

JP 2015-216191 A

  However, there is a portion where the wafer is not lifted up partially, and the outer peripheral edge where the wafer is not lifted up may come into contact with the tip of the holding claw, resulting in chipping of the wafer.

  The present invention has been considered in view of such a problem. In a transfer mechanism that holds the outer periphery of a wafer by allowing a holding claw to enter between the lower surface of the wafer and the holding surface, the gap between the lower surface of the wafer and the holding surface is provided. The purpose is to ensure the entry of the holding claws.

  The present invention transports a circular plate-like workpiece held on a holding surface of a holding table away from the holding surface, holds the outer peripheral portion of the plate-like workpiece by a holding portion, and carries out the plate-like workpiece from the holding table. At least three of the holding portions are arranged at an equal angle with the center of the plate-like workpiece as the center, and air is directed from the outer peripheral side of the plate-like workpiece held on the holding surface toward the plate-like workpiece. An air nozzle that ejects the plate, a guide column that contacts the outer peripheral edge of the plate-shaped workpiece and guides the plate-shaped workpiece in the surface direction of the holding surface, and enters the lower surface side of the outer peripheral portion of the plate-shaped workpiece and enters the plate A holding claw for holding the workpiece, a movable support portion provided with the air nozzle, the guide column, and the holding claw, advancing / retracting means for moving the movable support portion back and forth in the radial direction of the plate workpiece, Guy that allows the guide column to move in the radial direction of the plate-like workpiece And an urging means for urging the guide column in a direction toward the center of the plate-like work, and ejecting air from the air nozzle to float the plate-like work from the holding surface, By moving the movable support portion toward the center of the plate-like workpiece by means, the guide pillar is brought into contact with the outer peripheral edge of the plate-like workpiece, and the movable support portion is moved in the same direction, and the holding claw Is moved between the lower surface of the plate-like workpiece and the holding surface to hold the plate-like workpiece.

  In the present invention, the air nozzle blows air toward the center from the outer peripheral side of the plate-like work, the plate-like work is levitated, and the holding claw supports the plate-like work, and the holding claw is the lower surface of the plate-like work. The plate-like workpiece that has entered between the holding surface and the holding surface is held. Therefore, the plate-like workpiece can be lifted reliably and the holding claw can be moved between the lower surface and the holding surface of the plate-like workpiece, and chipping of the plate-like workpiece can be prevented.

It is a front view which shows the example of a conveyance mechanism. FIG. 6 is a partially enlarged plan view showing holding claws, air nozzles, and guide columns that constitute the transport mechanism. It is a partially expanded front view which shows the state which lowered | hung the air nozzle and made it contact the holding surface of a holding table. It is a partially expanded front view which shows the state which ejected air from the air nozzle and floated the plate-shaped workpiece | work from the holding surface. FIG. 5 is a partially enlarged front view showing a state in which air is ejected from an air nozzle to float a plate-like workpiece from a holding surface and a guide column is brought into contact with the outer peripheral edge of the plate-like workpiece. FIG. 5 is a partially enlarged plan view showing a state in which air is ejected from an air nozzle to float a plate-like workpiece from a holding surface and a guide column is brought into contact with the outer peripheral edge of the plate-like workpiece. Air is blown from the air nozzle to float the plate-shaped workpiece from the holding surface, and the holding claw is placed between the lower surface of the plate-shaped workpiece and the holding surface of the holding table with the guide column in contact with the outer peripheral edge of the plate-shaped workpiece. It is a partially expanded front view which shows the state made to approach. Air is blown from the air nozzle to float the plate-shaped workpiece from the holding surface, and the holding claw is placed between the lower surface of the plate-shaped workpiece and the holding surface of the holding table with the guide column in contact with the outer peripheral edge of the plate-shaped workpiece. It is a partially expanded plan view which shows the state made to approach to.

  A transport mechanism 1 shown in FIG. 1 is a mechanism that transports a plate-like workpiece W held on a holding surface 910 of a holding table 9 provided in various processing apparatuses and the like away from the holding surface 910 and includes a driving unit (not shown). A transfer arm 21 driven by a motor or an air cylinder), a shaft portion 22 hanging from the transfer arm 21, an upper plate 23 attached to the lower end of the shaft portion 22, and moving up and down with respect to the upper plate 23 At least three support shafts 31, a suspension part 32 attached to the upper ends of the respective support shafts 31 to support the support shafts 31 in a suspended state, and a lower plate fixed to the lower ends of the support shafts 31 33. The support shaft 31 is loosely fitted in a through hole 231 that penetrates the front and back of the upper plate 23. The hanging portion 32 is formed to have a larger diameter than the inner diameter of the through hole 231, and restricts the descending range of the support shaft 31.

  On the other hand, the holding table 9 includes a suction portion 91 made of a porous member and a frame 92 that supports the suction portion 91 from the lower side and the outer peripheral side. The suction part 91 is connected to a suction source 94 via an on-off valve 93. The upper surface of the suction portion 91 is a holding surface 910 that holds the plate-like workpiece W. By opening the on-off valve 93, a suction force is applied to the holding surface 910 to hold the plate-like workpiece W by suction. it can. The holding surface 910 also includes the upper surface of the frame 92 that is formed flush with the holding surface 910.

  The lower plate 33 is provided with at least three holding portions 3 that hold the plate-like workpiece W at equal angular intervals in the circumferential direction of the lower plate 33. Each holding portion 3 includes a movable support portion 4 that is movable in the radial direction of the plate-like workpiece W, and an advancing / retreating means 5 that advances and retracts the movable support portion 4 in the radial direction of the plate-like workpiece W. .

  Each advancing / retreating means 5 includes, for example, a piston rod 51 that extends in the radial direction, a cylinder 52 that moves the piston rod 51 in the radial direction, and a guide portion 53 that extends in the same direction as the piston rod 51. The movable support portion 4 is fixed to the tip of the piston rod 51, and the movable support portion 4 is also guided by the guide portion 53 and moves in the same direction as the piston rod 51 moves.

  Each movable support part 4 extends downward from the movable support part 4 and is formed in a substantially columnar guide pillar 6; a holding claw 7 extending downward from the movable support part 4 and further extending from the lower end toward the center direction; An air nozzle 8 that extends downward from the movable support 4 and ejects air from the lower end toward the center of the plate-like workpiece W is supported.

  The holding claw 7 and the air nozzle 8 are fixed to the movable support portion 4 or formed integrally with the movable support portion 4. At the tip of the holding claw 7, the lower surface 71 is formed in parallel with the holding surface 910, and the upper surface 72 is a slope that descends toward the center of the plate-like workpiece W.

  A flow path 81 is formed inside the air nozzle 8, and one end of the flow path 81 communicates with the air source 82. On the other hand, the other end of the flow path 81 is open at the spout 83. The jet outlet 83 at the tip of the air nozzle 8 is at a position lower than the lower surface 71 of the holding claw 7. Further, the tip of the holding claw 7 is positioned closer to the plate-like workpiece W than the jet nozzle 83 of the air nozzle 8.

  As shown in FIG. 2, the tip of the holding claw 7 faces the center of the plate-like workpiece W. On the other hand, two air nozzles 8 are provided for one holding claw 7. The two air nozzles 8 have their ejection ports 83 facing the tips of the holding claws 7.

  As shown in FIG. 1, an urging means 61 that urges the guide column 6 in the direction toward the center of the plate-like workpiece is interposed between the movable support portion 4 and the guide column 6. As this urging means 61, for example, a spring can be used. As shown in FIG. 2, the guide pillar 6 may be configured to come into contact with the plate-shaped workpiece W by fixing the guide pillar 6 to the tip of the arm 62 and turning the arm 62. In this case, as the urging means 61, for example, a spiral spring can be used.

  Below, the case where the plate-shaped workpiece | work W hold | maintained at the holding table 9 is carried out using the conveyance mechanism 1 comprised in this way is demonstrated. As shown in FIG. 3, the outer periphery Wc of the plate-like workpiece W is rounded and the outer peripheral edge Wd is a portion having the largest outer diameter in the outer peripheral part Wc. The on-off valve 93 is opened, the lower surface Wb of the plate-like workpiece W is held by the holding surface 910, and the upper surface Wa is exposed.

  First, the transport arm 21 shown in FIG. 1 is turned so that the center of the lower plate 33 coincides with the center of the suction portion 91. Then, the entire transport mechanism 1 is lowered, and the lower surface 84 of one of the two air nozzles 8 is brought into contact with the holding surface 910 with respect to one holding claw 7 as shown in FIG. At this time, the support shaft 31 moves up in the through hole 231, and the holding unit 3 moves upward relative to the upper plate 23. When the lower surfaces 84 of the at least three air nozzles 8 come into contact with the holding surface 910 in this way, the jet nozzle 83 of the air nozzle 8 is directed between the lower surface Wb of the outer peripheral portion Wc of the plate-like workpiece W and the holding surface 910. Further, by bringing the lower surface 84 of the air nozzle 8 into contact with the holding surface 910, the lower plate 33 suspended by the hanging structure is lifted from the upper plate 23 and is parallel to the holding surface 910. The lower surfaces 84 of the two air nozzles 8 may be formed flush with each other with respect to one holding claw 7. Further, one air nozzle 8 may be provided for one holding claw 7.

  Next, as shown in FIG. 4, the on-off valve 93 is closed so that no suction force acts on the holding surface 910. Then, with the lower surface 84 of the air nozzle 8 in contact with the holding surface 910, the air 831 is ejected from the ejection ports 83 of all the air nozzles 8 positioned on the outer peripheral side of the plate-like workpiece W as shown in FIG. As a result, the outer peripheral portion Wc of the plate-like workpiece W is levitated. As shown in FIG. 4, the entire plate-like workpiece W may float, but it is sufficient that at least a portion of the outer peripheral portion Wc located on the inner peripheral side of the holding claw 7 is levitated.

  Next, as shown in FIGS. 5 and 6, the advancing / retreating means 5 moves the movable support portion 4 toward the center of the plate-like workpiece W in a state where the ejection of the air 831 from the ejection port 83 is continued. The guide column 6 is brought into contact with the outer peripheral edge Wd of the plate-like workpiece W to hold the outer peripheral portion Wc. As a result, the plate-like workpiece W is not laterally displaced by at least three guide columns 6. The three guide pillars 6 are driven by the respective advancing / retreating means 5 and each move independently toward the center of the plate-like workpiece W. Therefore, the center of the plate-like workpiece W and the center of the lower plate 33 are equal to each other. If not, the plate-like workpiece W is guided in the surface direction of the holding surface 910. After that, all the guide pillars 6 come into contact with three locations of the outer peripheral edge Wd of the plate-like workpiece W, and the plate-like workpiece W can be prevented from being displaced in the surface direction of the holding surface 910.

  Next, as shown in FIGS. 7 and 8, the advancing / retreating means 5 further moves the movable support portion 4 toward the center of the plate-like workpiece W in a state where the ejection of the air 831 from the ejection port 83 is continued. The holding claw 7 is caused to enter between the holding surface 910 and the lower surface Wb of the plate-like workpiece W. Then, as the holding claw 7 moves toward the center of the plate-like workpiece W, the plate-like workpiece W rises along the inclination of the upper surface 72 of the holding claw 7, and the plate-like workpiece W is moved by at least three holding claws 7. Retained. When the holding claw 7 is caused to enter between the holding surface 910 and the lower surface Wb of the plate-like workpiece W, the outer peripheral portion Wc of the plate-like workpiece W is levitated by the ejection of air from the outlet 83 of the air nozzle 8. Therefore, the holding claw 7 can be surely entered and held.

  When the holding claw 7 enters between the holding surface 910 and the lower surface Wb of the plate-like workpiece W, since the outer peripheral edge Wd of the plate-like workpiece W is supported by the guide column 6, the plate-like workpiece W is It is guided by the side surface of the guide column 6 and rises. Therefore, it is possible to prevent the plate-like workpiece W from being laterally shifted in the surface direction of the holding surface 910.

  Next, the plate-like workpiece W is separated from the holding surface 910 of the holding table 9 by raising the transport arm 21 shown in FIG. 1 while maintaining the horizontal position of the holding claw 7. The plate-like workpiece W can be transferred to a desired position by turning the transfer arm 21 or the like.

  As described above, the transport mechanism 1 causes the plate-like workpiece W to float by the air nozzle 8 ejecting air from the outer peripheral side of the plate-like workpiece W toward the plate-like workpiece W, and the guide column 6 is the plate-like workpiece W. The holding claw 7 holds the plate-like workpiece W that has entered between the lower surface Wb of the plate-like workpiece W and the holding surface 910. Accordingly, the plate-like workpiece W can be surely lifted and the holding claw 7 can be moved between the lower surface Wb of the plate-like workpiece W and the holding surface 910, thereby preventing the plate-like workpiece W from being chipped. it can.

  Further, the guide column 6, the holding claw 7 and the air nozzle 8 are supported by the movable support portion 4, and the advance / retreat means 5 advances and retracts the movable support portion 4 in the radial direction of the plate-like workpiece W, whereby the guide column 6, the holding claw 7 and the air nozzle 8 can be moved, so that it is not necessary to provide separate drive mechanisms for the guide column 6, the holding claw 7, and the air nozzle 8, and the apparatus configuration can be prevented from becoming complicated.

  In the above embodiment, the suction portion 91 of the holding table 9 is connected only to the suction source 94 via the on-off valve 93, but the suction portion 91 is connected to the suction source 94 and the air supply source via the switching valve. It may be configured to be selectively connected. In such a configuration, in parallel with the ejection of air from the ejection port 83, the suction part 91 is communicated with the air supply source and the air is ejected from the holding surface 910, so that the plate-like workpiece W is more reliably held. From 910.

1: Transfer mechanism 21: Transfer arm 22: Shaft portion 23: Upper plate 231: Through hole 3: Holding mechanism 31: Support shaft 32: Suspension portion 33: Lower plate 4: Movable support portion 5: Advance / retreat means 51: Piston rod 52: Cylinder 53: Guide part 6: Guide column 61: Biasing means 7: Holding claw 71: Lower surface 72: Upper surface 8: Air nozzle 81: Flow path 82: Air source 83: Outlet 84: Lower surface 9: Holding table 91: Suction part 910: Holding surface 92: Frame 93: On-off valve 94: Suction source W: Plate-like work Wa: Upper surface Wb: Lower surface Wc: Outer peripheral part Wd: Outer peripheral edge

Claims (1)

A transport mechanism that transports a plate-shaped workpiece from the holding table by holding a circular plate-shaped workpiece held on the holding surface of the holding table away from the holding surface and holding the outer peripheral portion of the plate-like workpiece by the holding portion. ,
At least three of the holding portions are arranged at an equal angle around the center of the plate-like workpiece,
An air nozzle that ejects air from the outer peripheral side of the plate-like workpiece held on the holding surface toward the plate-like workpiece;
A guide column that contacts the outer peripheral edge of the plate-like workpiece and guides the plate-like workpiece in the surface direction of the holding surface;
Holding claws that enter the lower surface side of the outer peripheral portion of the plate-like workpiece and hold the plate-like workpiece;
A movable support portion in which the air nozzle, the guide column, and the holding claw are disposed;
Advancing and retracting means for advancing and retracting the movable support portion in the radial direction of the plate-like workpiece;
A guide part that allows the guide column to move in the radial direction of the plate-like workpiece;
A biasing means for biasing the guide column in a direction toward the center of the plate-like workpiece;
With
Air is ejected from the air nozzle to float the plate-like workpiece from the holding surface, and the guide column is moved to the center of the plate-like workpiece by moving the movable support portion toward the center of the plate-like workpiece by the advance / retreat means. A transport mechanism for holding the plate-like workpiece by bringing the movable support portion into contact with the outer peripheral edge of the plate-like workpiece, moving the movable support portion in the same direction, and causing the holding claw to enter between the lower surface of the plate-like workpiece and the holding surface.

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