JPS6231630A - Handler for wafer conveyance - Google Patents

Abstract

PURPOSE:To provide a titled handler which serves to both recover and collect and enables a wafer to be taken out from the arbitrary spot of a cassette, by a method wherein a guide groove, adapted to regulate movement of a first and a second arm, is provided. CONSTITUTION:A shaft 4a and a gear 28a are rotated along with running of a motor. Since the shaft 4a and a second arm 5a are secured, the second arm 5a is rotated clockwise around the shaft 4a. Since, with second arms 5 (5a, 5b) rotated, the second arms 5are coupled with first arms 7 (7a, 7b) through shafts 6 (6a, 6b), rotary motion is also transmitted to the first arm 7 along with rotation of peripheral track movement of the shaft 6. Since rotary members 11 (11a, 11b) are engaged with grooves 12 (12a, 12b) provided in an upper plate 14, from relation between the circumferential track movement and the shapes of the rotary member 11 and the groove 12, the first arm 7 is rotated counterclockwise around the shaft 6 by means of the rotary member 11 as the first arm is constrained by the groove 12. When, after the shafts 4 (4a, 4b) are rotated in a specified rotary angle arc, a finger 1 is inserted in a cassette 2, the finger 1 is lifted up, and a wafer 3 is placed on the finger 1.

Description

[Detailed Description of the Invention] [Field of the Invention] The present invention relates to a wafer transport handler used in the manufacturing process of ICs, LSIs, etc. The present invention relates to a small-sized wafer transfer handler that inserts and removes wafers using a so-called pantograph type hand, which is a type of linear hand.

[Conventional technology] FIG. 4 shows a conventional wafer transfer handler.

In the figure, 101 is a cassette, 102 is a wafer,
101a is a shelf section on which wafers are placed. 103 is a gear, and 104 is a cassette hanging with a rack, which is moved up and down by the rotation of the gear 103. 105 is a conveyor belt. This device has a structure in which a cassette containing wafers is installed above a rotatable belt so that it can move up and down, and the cassette is moved downward to sequentially place the wafers in the cassette on the belt from the bottom and take them out. It has become. For this reason, the wafers stored in the cassette are fed in a non-sequential order.
For example, it was not possible to take out every other sheet. This technique of taking out wafers in an arbitrary order is particularly important in wafer inspection equipment.

Furthermore, in conventional wafer inspection equipment using the handler shown in Figure 4, two cassettes are always provided, one for supplying wafers and the other for collecting wafers, and wafers not to be inspected are also removed from the supply cassette and collected. It was necessary to take the trouble of storing it in a special cassette. As described above, two cassettes are required, which has the drawback of forcing the device to be larger.

[Object of the Invention] The present invention has been made in view of the above-mentioned drawbacks of the conventional example.The cassette is used for both collection and supply, and the wafers can be taken out from any part of the cassette and returned to the place where they were taken out. It is an object of the present invention to provide a smaller wafer transport handler that can be returned.

[Example] Figures 1 to 3 show an example of the present invention. In the drawings, suffixes raJ and rbJ are attached to the reference numbers of a pair of parts, but the suffixes are omitted only when both are referred to collectively. In FIGS. 1 and 2, 1 is a finger on which a wafer is placed, 2 is a cassette, and 3 is a wafer. 4
is the rotating shaft of the second arm 5, which is connected to the shaft 4 and the motor 29. 28 and the second arm 5 are fixed so that their rotations are synchronized. Reference numeral 6 denotes a common rotating shaft of the first arm 7 and the second arm 5, and the shaft 6 and the first arm 7 are fixed so that their rotations are synchronized. Note that the distance between the axes of the first arm 7 and the distance between the axes of the second arm 5 are approximately equal. 8 is a rotating shaft of the first arm 7 on the finger 1 side, and is rotatable with respect to the finger 1. 9 is a gear, and the first arm 7, shaft 8, and gear 9 are fixed so that their rotations are synchronized.

Furthermore, the gears 9a and 91) are in mesh with each other. 10 is a shaft fixed to the first arm 7; 11 is a rotating member;
It is rotatably mounted on the 12 is a curved groove provided in the upper plate 14, and the rotating member 11 is engaged with the groove 12. 13 is a connecting member that connects the base 26 and the upper plate 14. The finger 1, arm 5.7, rotating member 11, etc. constitute a pantograph type hand that is a feature of the present invention.

20 is a laser beam, 21 is a laser source, 22 is a half mirror
The laser beam 20 emitted from the laser source 21 is reflected toward the total reflection mirror 23. A photodiode 24 receives the reflected light from the total reflection mirror 23. 25 is a connecting member for fixing the laser source 21 to the base 26. The base 26 also supports an arm telescoping drive section 27. Gears 28a and 28b in the arm telescopic drive section 27 mesh with each other, and the rotation of the motor 29 is transmitted to the gear 28a and at the same time to the gear 28b.

In the drawing, screws and keys for fixing each member, members for smooth movement of the first arm 7 and second arm 5, and finger 1 are shown.
Supporting members, members for removing backlash of a series of gears, etc. are not shown.

The operation of the handler having the above configuration will be explained with reference to FIG. Before taking out the wafer 3 from the cassette 2,
The whole unit is raised and lowered by a whole unit elevating device (not shown), and set at an appropriate position for inserting the finger 1. This is done by detecting the laser beam 20 reflected by the mirror 23 with the photodiode 24 via the half mirror 23.

When detecting the position of a wafer, the arm is in a state in which no wafer 3 is placed in FIG. 3, and the first arm and the second arm extend in the direction opposite to the cassette 2 when viewed from the shaft 4. This state is a state in which the fingers 1 are retracted, and will hereinafter be referred to as a "retracted" state of the hand.

When the appropriate position is detected, a rotation command is given to the motor 29 in the arm extension/contraction drive unit 27 from an electric command unit (not shown). Hereinafter, for the sake of brevity, only one arm group will be described. When the motor 29 rotates, the shaft 4a,
Gear 28a rotates. This direction of rotation is clockwise rotation in FIG. Since the shaft 4a and the second arm 5a are fixed, the second arm 5a rotates clockwise about the shaft 4a. When the second arm 5 rotates, since the second arm 5 and the first arm 7 are connected by the shaft 6, the rotational motion is also transmitted to the first arm 7 along with the circumferential orbital movement of the shaft 6. . That is, since the rotating member 11 rotatably connected to the first arm 7 engages with the groove 12 provided in the upper plate 14, the circumferential orbital movement of the shaft 6 and the shapes of the rotating member 11 and the groove 12 are controlled. Due to the relationship between the first arm 7 and the rotating member 11
It performs a counterclockwise rotation about axis 6 while being restrained by 12.

Here, the shape of the groove 12, that is, the locus of the shaft 10, is determined by the distance from the shaft 6 to the shaft 8 being R, and the ratio of the distances from the shaft 6 to the shaft 10 and from @10 to the shaft 8 being m to n. In this case, it is preferable to form the XY coordinate system with axis 4 as the origin so as to satisfy the following general formula. In this case, the first
The arm 7 rotates about the axis 6 in a direction opposite to the rotation of the second arm b about the axis 4 and by twice the angle.

Furthermore, as mentioned above, since the gear 28a is meshed with the gear 28b, the other arm group operates as described above and the laser beam 28b is in mesh with the gear 28a.
Performs a line-symmetrical operation with respect to 0.

The first arm 7a and the second arm 5a are configured as a pair, and the tip of the first arm 7 is restrained by the finger 1. Therefore, as the first arm 7 rotates from side to side with respect to the second arm 5, the finger 1 In the right direction, that is, into the cassette 2. The entered state, that is, the hand is "extended"
FIG. 1 is a diagram showing the state. At this time, if there is a manufacturing error in the distance between the axes of the pair of first and second arms, and the rightward movement distance and movement speed of the shafts 8a and 8b are not the same, the finger 1 will be twisted. However, the gears 9a and 9b serve to prevent this.

In this way, when the shaft 4 rotates by a certain rotation angle and the finger 1 is inserted into the cassette 2, the finger 1 is lifted by the operation of the whole unit lifting device (not shown).
A wafer 3 is placed on the finger 1.

When the wafer 3 is placed, a wafer take-out operation is started.

With reference to FIGS. 1 and 2, the arm extension/contraction drive unit 27
When a command to rotate the motor 29 in the opposite direction to that at the time of entry is issued from an electric command unit (not shown) inside the motor 29, the first arm 7 rotates through a series of operations that are exactly opposite to those described above, and the finger 1 moves to the cassette. Escape from 2. FIG. 3 is a diagram showing a state in which escape has been completed.

Wafer 3 taken out from cassette 2 as described above
The wafer 3 is transported to the next step (not shown), and the wafer 3 that has been processed in the next step is transported into the cassette 2 by following the reverse operation to the above-described operation.

Further, by arbitrarily changing the rotation angle of the shaft 4, it is also possible to arbitrarily change the stroke for inserting and removing the wafer.

Note that the present invention is not limited to the above-described embodiment, and for example, the gear 9 may be partially cut out to form a sector gear. Further, in this embodiment, the shaft 4 is used as the drive shaft to drive the pantograph type hand, but it is also possible to construct a structure in which the shaft 10 of the rotating member 11 slides and use this part as the drive section. be. Further, in the above description, the shaft 10 is provided between the shafts 6 and 8, but it is also possible to provide the shaft 10 on an extension of the shaft 6 or shaft 8 side.

[Effects of the Invention] As explained above, according to the present invention, there is no need to take out the wafers sequentially from the bottom of the cassette, so any wafer can be taken out at any time. There is no need to provide a separate cassette, and the device can be made smaller. Furthermore, since the pair of arms are bent from being extended and then moved to the opposite side, the maximum stroke can be used in a narrow space, making the device more compact. Furthermore, compared to the conventional method of taking out wafers from a cassette using a belt, there is no possibility of dust adhering to the wafers. Also, the second
By changing the drive force of the arm, it is possible to arbitrarily change the stroke of movement of the wafer support member.

[Brief explanation of drawings]

FIG. 1 is a top view showing a state in which a wafer transfer handler according to an embodiment of the present invention has entered a cassette, FIG. 2 is a longitudinal sectional view of the apparatus shown in FIG. 1, and FIG. 1 is a top view showing a state in which the hand of the apparatus is "shrinked" and takes out a wafer, and FIG. 4 is a side view and a sectional view showing a conventional example.

Claims (1)

[Claims] 1. A wafer support member configured to place a wafer on a surface, and having first to third shafts, the first shaft being pivotable to the wafer support member. a pair of first arms connected to the base; a second arm; and a guide groove that engages with a third shaft of the first arm to synchronize movement of the first arm and the second arm. 2. The wafer transfer handler according to claim 1, wherein the rotation angle of the first arm is twice the rotation angle of the second arm around the rotation axis.