JPH0442136B2 - - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to an apparatus for peeling a wafer from a plate after a wafer polishing process and automatically feeding the wafer to a predetermined ejection position.

Background of the Invention and Prior Art During the manufacturing process of wafers, there is a step of polishing the surface thereof. During the polishing process, a plurality of wafers are placed in position on the surface of the plate and releasably secured by an adhesive. After the polishing process, the wafer is peeled off from the surface of the plate and stored inside a predetermined wafer cassette case.

Conventionally, all such wafer peeling operations have been performed manually. In other words, the worker holds a cutter in his right hand, inserts the cutting edge between the plate and the wafer on the top surface of the plate, peels the adhered wafer from the surface of the plate, and then
With the left hand, the wafer is shifted sideways on the top surface of the plate, and with the vacuum pad transferred to the right hand, the vacuum pad is held against the back side of the wafer, and then the wafer is discharged to a predetermined position. Such manual work is inefficient, and also tends to damage or contaminate the wafers when they are ejected. Under these circumstances, automation of this type of wafer peeling work is desired.

OBJECTS OF THE INVENTION AND SOLUTIONS THEREOF The object of the invention is therefore to enable automatic peeling of the wafers on the plate after the wafer polishing process and subsequent ejection to a predetermined position.

Therefore, the present invention transports a large number of plates to a working position by a transfer means, determines the position of the wafers on the plates at that position, and peels off the wafers on the plates while controlling the position with a cutter. The peeled wafer is automatically delivered to a predetermined discharge position by chucking the handling means. Here, the wafer position detection means is constituted by a proximity sensor or the like, and the position of the wafer on the plate can be accurately detected in relation to the rotation of the index table and the output waveform of the sensor. Therefore, the subsequent wafer peeling operation and the wafer ejection operation after peeling can be performed automatically by mechanical means without malfunction.

Configuration of the Invention Hereinafter, the configuration of the present invention will be specifically explained based on the drawings.

The automatic wafer peeling apparatus 1 of the present invention includes a transfer means 2, an index table 3, an indexing rotation means 4, a position detection means 5, a peeling means 6,
It is composed of a stopper 7, a chuck 8 and a handling means 9. All of these are provided on the machine stand 10.

The transfer means 2 is for moving the plurality of plates 11 from the carry-in position to the work position, and includes, for example, two rows of roller conveyors 12 that are movable up and down, and that are movable in the carry-in direction between them. It is equipped with 13 vacuum chucks. The roller conveyor 12 has a pair of stoppers 12a at its terminal end, and is configured by a cylinder or the like in a direction perpendicular to the machine base 10.
It is supported in a vertically movable manner within a predetermined height range. Further, the vacuum chuck 13 is attached to a rectangular rocking plate 14 in an upward direction. The swing plate 14 is attached to a U-shaped frame 16 in plan view by a horizontal support shaft 15 at approximately the center thereof. This frame 16 has a push pin 16a on the top surface,
It is attached to a piston rod 18 of a small cylinder 17, which in turn is attached to a piston rod 20 of a large stroke cylinder 19, which is mounted horizontally on the machine base 10.
is installed in a horizontal position. The swing plate 14 is inclined low on the side of the vacuum chuck 13 due to the eccentric load of the vacuum chuck 13, but it is tilted in the opposite direction by the piston rod 28 of the pen cylinder 27 mounted downward. It's starting to lean in the direction.

Note that a lifter 21 is provided at the loading position of the plate 11. This lifter 21 is
The stocker 23 carried by the trolley 22 is held by a fork 24, and as the plates 11 are removed, the stocker 23 is raised one by one.
The take-out position of the top plate 11 is always set at the same height. The stopping position of this truck 22 is set by guide rails 26 and the like. Of course, a plurality of, for example, four, wafers 25 are fixed on the upper surface of the plate 11 with an adhesive in a releasable state.

The index table 3 has an oval shape when viewed from above, and is rotatably supported by an index rotation means 4 between parallel roller conveyors 12. As shown in FIG. 3, this index table 3 has a positioning slope 29 formed on its outer periphery, and a plurality of suction holes 31 integrally formed on a flat chuck surface 30 between them. ing. Note that the above-mentioned index rotation means 4
is equipped with a gear motor or the like inside, and rotates the index table 3, for example, once at a constant speed and intermittently by a predetermined angle. Such determination of the rotation angle can be accurately regulated by an internal limit switch and dog, or by the amount of motor rotation.

Further, the position detecting means 5 and the stopper 7
is supported by a support plate 32 at a working position, that is, above the index table 3, so that it can move forward and backward, and can also move up and down. That is, the position detecting means 5 is constituted by an optical sensor or the like, and is attached to the piston rod 34 of the vertical cylinder 33, as shown in FIG. Further, the stopper 7 is supported in a floating state with respect to a connecting plate 37 by a vertical rod 35 and a coil spring 36. This connecting plate 37 is connected to a piston rod 39 of a cylinder 38 attached to the upper surface of the support plate 32, and is connected to the left and right guide rods 40.
This makes it possible to freely slide on the sleeve 41 of the support plate 32.

Further, the support plate 32 is supported by a pair of sliding guide rods 42 in a horizontal state with respect to the machine frame 43, and a connecting member 44 at the rear end is supported by a pair of sliding guide rods 42.
It is screwed into a feed screw 46 by a feed nut 45 attached to the portion. The feed screw 46 is connected to a feed motor 47 at one end, and rotatably supported by a bearing 48 at the other end.

Next, the peeling means 6 is shown in detail in FIGS. 5 to 7. This peeling means 6
is equipped with a cutter 49 to be inserted between the wafer 25 to be separated and the plate 11. This cutter 49 is attached to a cutter stand 52 in an angle-adjustable manner by means of a horizontal shaft 51 of a holder 50, a long hole, and screwing means. The cutter stand 52 is supported by a pair of vertical float shafts 53 at the left and right holes so as to be movable up and down, and is supported by a spring 54.
It is urged in the downward direction by the float shaft 53, and stops when it hits the angle 55 of the float shaft 53.
A pair of float shafts 53 are attached to the upper surface of a rotating plate 57 attached to the upper surface of a cylindrical shaft 56, and this cylindrical shaft 56 is attached to a ball bearing 58.
It is rotatably supported by the housing 59. Further, this housing 59 is connected to a support plate 61 by a pair of connecting shafts 60. The pair of connecting shafts 60 are connected to a slide block 62.
It can be slid vertically by a sliding guide tube 63 attached to the slide guide tube 63, and is biased downward by a biasing spring 64 provided between the sliding guide tube 63 and the support plate 61. has been done.

The slide block 62 is supported so as to be able to slide in the horizontal direction by a pair of guide bars 66 spanned over a machine frame 65, and is supported vertically by a ball bearing 67 at the center. It is rotatably supported. This spline shaft 68 fits into a spline hole of the cylindrical shaft 56, and an arm 69 is attached to the lower end.
cam roller 70 is held. The cam roller 70 is located at an eccentric position with respect to the spline shaft 68 and fits inside a turning cam 71 supported by the machine frame 65. As shown in FIG. 6, this turning cam 71 shifts from one side to the other side as it goes in the direction of travel.

On the other hand, the slide block 62 is connected to a feed screw 73 by a feed nut 72 attached thereto.
is connected to. This feed screw 73 is connected to the machine frame 65.
It is rotatably supported by ball bearings 74 at both ends, and is connected to a drive motor 76 attached to the machine frame 65 by a coupling ring 75. In addition, this slide block 62 has
A dog 77 is fixed, and a sensor 78 is attached to the machine frame 65 correspondingly. Further, a roller 79 is rotatably supported on the support plate 61 by a horizontal roller shaft. This roller 79 faces the inside of the groove of a direct-acting cam 80 attached to the bottom of the machine frame 65.

Further, the chuck 8 is, for example, a vacuum chuck, and is attached to the tip of the arm 81 of the handling means 9 in an upward direction. This handling means 9 moves the wafer 25 after separation from the separation position to the carry-in position of the transport unit 82 by the rotational movement of the arm 81. This transport unit 82 is composed of two belt conveyors 83 and moves the wafers 25 carried by the handling means 9 in the direction of the belt conveyor 83 and into a plurality of storage cassettes 84. . This storage cassette 8
4 is provided for each size of wafer 25, and intersects with the belt conveyor 83 by a conveyor 85 on the entrance side. A defective product storage box 86 and a dumping conveyor 87 are provided on the entrance side of the transport unit 82.

Effects of the Invention Next, the effects of the invention will be explained together with a series of operations of the automatic peeling device 1.

The wafers 25 after polishing are neatly stored inside the stocker 23 while being fixed to the plate 11, and transported to the automatic peeling device 1 by the cart 22.
is sent to the loading position. In this state, the trolley 22
is regulated by the guide rail 26 and stops at the correct position. At this time, the lifter 21 inserts its fork 24 below the stocker 23,
After the plates 11 are taken out, they are raised one after another, and the plate 11 at the topmost take-out position is always set at a constant height.

After positioning the plate 11, the roller conveyor 12 of the transfer means 2 is raised by a vertical cylinder or the like to a predetermined height, that is, the height shown by the imaginary line in FIG. 2, in preparation for taking out the plate 11. . In this state, the large cylinder 19 first moves the plurality of vacuum chucks 13 between and below the roller conveyor 12 by advancing its piston rod 20. When the piston rod 20 has moved to its forward limit, the small cylinder 17 moves the piston rod 18 forward, thereby moving the vacuum chuck 13 together with the frame 16 below the uppermost plate 11 inside the stocker 23. move it to. Note that the cylinders 19 and 17 may operate overlappingly. At this time, since the pen cylinder 27 is retracting its piston rod 28, the swing plate 14 moves to below the uppermost plate 11 while maintaining the inclination shown in FIG. After this movement, the pen cylinder 27 moves the piston rod 28 forward, ie, downward, so that the rocking plate 14 is brought into a substantially parallel position. At this time, the vacuum chuck 13 is attracted to the lower surface of the uppermost plate 11 and becomes ready to be pulled out.

Thereafter, the large cylinder 19 moves its piston rod 20 backward, so that the uppermost plate 11 is pulled by the vacuum chuck 13, rides on the roller conveyor 12, and is pulled out from inside the stocker 23 to the working position. It moves until it hits a stopper 12a provided on the roller conveyor 12 and stops.

Subsequently, the vacuum chuck 13 stops its suction operation, and the pen cylinder 27 returns the swing plate 14 to its original tilted state.
is separated from the lower surface of the plate 11 after being pulled out. In this state, the small cylinder 17 moves the vacuum chuck 13 to the retracted position by retracting its piston rod 18.

When the carrying-in operation is completed in this way, the roller conveyor 12 is lowered to its original height, so that the plate 11 on the roller conveyor 12 is
moves onto the index plate 3 while being guided by the slope 29. Here, the index plate 3 has suction holes 31 on its chuck surface 30.
By generating a negative pressure air flow, plate 11 is held in chuck condition along with wafer 25.

During this time, the feed motor 47 moves the support plate 32 to the first position by rotating the feed screw 46.
It is advanced to the position shown in the figure. In this advanced position, the cylinder 33 brings the position detection means 5 closer to the wafer 25 on the plate 11 by lowering its piston rod 34.

Thereafter, the index rotation means 4 rotates the index table 3. This position detection means 5
detects the number and size of wafers 25 while the index table 3 is rotating, and generates information necessary for indexing rotation of the index table 3. Here, the number of wafers 25 can be detected by counting the number of signals from the position detection means 5. Further, the size of the wafer 25 can be calculated based on the pulse width of the output from the position detecting means 5 in relation to the rotational speed of the index table 3. Then, depending on the detected size of the wafer, the support plate 32 is moved by the motor 47.
The position of the stopper 7 is set in advance. In this way, after the index table 3 has rotated once, the indexing rotation means 4 again intermittently rotates the index table 3 by a predetermined angle, and sequentially indexes a plurality of wafers 25 to predetermined peeling positions. To go. This peeling position is the position of the wafer 25 indicated by the dashed line in FIG. Note that this position detection means 5
While the index table 3 is rotating, a black mark or the like on the upper surface of the wafer 25 is detected, and defective products are also confirmed at the same time.

In this way, when a certain wafer 25 is guided to a predetermined peeling position, the cylinder 38
By lowering the piston rod 39, the stopper 7 is brought into contact with the upper surface of the plate 11, and its outer peripheral portion is brought close to the outer peripheral surface of the wafer 25. In this state, the wafer peeling operation by the peeling means 6 is started.

First, since the slide block 62 is in the retracted position as shown in FIG.
is located at a high position and set at an appropriate inclination angle.

In this state, when the drive motor 76 is started in a predetermined rotational direction, the rotation of the feed screw 73 causes
Since the slide block 62 is guided in the forward direction by the pair of guide bars 66, the cutter 49
moves in a direction approaching the wafer 25, as shown in FIG. 8A, while remaining at a high position.

During this movement process, the roller 79 of the support plate 61 descends along the smooth curve of the direct-acting cam 80, imparting a similar movement to the cutter stand 52. As a result, the cutter 49 moves forward and descends along the curve of the linear drive cam 80, as shown in FIG. 8B.
It comes into contact with the upper surface of the plate 11. In addition,
The cutter 49 is pressed against the upper surface of the plate 11 by a spring 54. After that, the slide block 62 moves forward, so the cutter 49
slides on the upper surface of the plate 11 and enters the lower surface of the wafer 25 as shown in FIG. 8C.

On the other hand, during this forward movement, the cam roller 70 is guided by the turning cam 71 and rotates counterclockwise by a certain angle about the spline shaft 68, as shown in FIG. This rotational movement of the spline shaft 68 is ultimately applied to the cutter 49, so the cutter 49 is moved as shown in FIGS. 8C and 8D.
It moves forward while turning and penetrates deeply into the underside of the wafer 25. At this time, the cutter 49 finally enters the lower surface of the wafer 25 with a wider blade width than before turning as shown in FIG. 8E.

In this way, the wafer 25 is transferred to the plate 11.
It is reliably peeled off from the top surface. In this peeling state, the handling means 9 has its arm 81
is rotated in the counterclockwise direction in FIG. Hold.
After that, since the arm 81 rotates clockwise,
The peeled wafer 25 is transferred from the upper surface of the plate 11 onto the belt conveyor 83 of the transport unit 82. These two belt conveyors 83 are
At any time or upon receiving the wafer 25,
The wafers 25 are moved in the transport direction to move the wafers 25 toward their respective storage cassettes 84. Here, since the corresponding conveyor 85 is rotating in advance according to the size of the wafer 25 being sent, the wafer 25 on the belt conveyor 83 is transferred from the belt conveyor 83 to the rotating conveyor 85.
The items are sorted and stored in corresponding storage cassettes 84. Of course, if the wafer 25 is a defective product, the wafer 25 is delivered into the defective product storage box 86 because the delivery conveyor 87 is rotating.

In this way, the peeling operation for one wafer 25 is completed. Thereafter, a new wafer 25 is guided to a predetermined separation position by the index table 3, and the same operation as described above is repeated.

When all the wafers 25 have been peeled off from the top surface of the plate 11, the roller conveyor 12 is raised, and then the cylinder 19 moves the frame body, and the frame body 16, by its push pins 16a, moves onto the plate 11. is moved to the original position of the stocker 23. Such a series of sequential operations can be realized by detecting the movement of the movable part using a limit switch or the like and controlling it using a sequence circuit or the like.

Modifications of the Invention In the above embodiment, the transfer means 2 is constructed with the roller conveyor 12 and the vacuum chuck 13 that can move back and forth as main parts. For example, it may be configured by combining a step-type transport mechanism and an index table 3 that can be raised and lowered.

Further, in the embodiment described above, chucking of the wafer 25 in a peeled state is performed on the upper surface of the plate 11. However, this chat is a stopper of 7
The peeled wafer 25 may be slightly protruded from the index table 3, and the chuck 8 may be able to adsorb the wafer 25 on the back side of this protruding portion. In this case, a pair of left and right stoppers 7 are provided in order to prevent the wafer 25 from moving in the lateral direction in a peeled state.

Effect of the invention The present invention provides the following unique effects.

The polished wafer is transported together with the plate to a predetermined working position by a transfer means,
The wafers are sequentially indexed to the peeling position by an index table, and the size and number of wafers on the plate are automatically detected during the indexing process. Work can be automated.

The wafer on the plate is peeled off from the front surface by the cutter, chucked on the back side in the peeled state, and discharged to a predetermined position by the handling means, so the peeling work and subsequent discharge work are automated. In addition, wafer damage and contamination during the chucking and transportation process are eliminated, resulting in a higher product yield.

[Brief explanation of drawings]

Fig. 1 is a plan view of the automatic wafer peeling apparatus of the present invention, Fig. 2 is a front view of the apparatus, Fig. 3 is a sectional view of the index table, and Fig. 4 is a side view of the position detection means and stopper portion. , FIG. 5 is a vertical sectional view of the peeling means seen from the front, FIG. 6 is a plan view of the cam portion, FIG. 7 is a vertical sectional view of the peeling means seen from the side, and FIG. 8 is a plan view showing the peeling operation. It is. 1... Wafer automatic peeling device, 2... Transfer means, 3... Index table, 4
... Index rotation means, 5 ... Position detection means, 6
... Peeling means, 7 ... Stopper, 8 ... Chack, 9 ... Handling means, 11 ... Plate, 12 ... Roller conveyor, 21 ... Lifter, 23 ... Stocker, 25 ... Wafer,
49...Cutter, 82...Transportation unit.

Claims (1)

[Claims] 1. A transfer means for transporting a plate on which a plurality of wafers are bonded to a working position, an index table for checking the plate at the working position, a means for indexing and rotating the index table, and a means for rotating the wafers when the index table is rotated. a position detection means for detecting a position; a peeling means having a cutter extending between the wafer and the plate; a stopper that comes close to or comes into contact with the outer circumference of the wafer during a peeling operation to restrict movement of the wafer; An automatic wafer peeling apparatus comprising: a chuck for holding a peeled wafer; and a handling means for reciprocating the chuck between a peeled wafer position and a discharge position.