JPS622457B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transfer device used for transferring a substrate to be processed between a boat for holding a substrate to be processed in a processing apparatus for manufacturing semiconductor devices, such as a plasma processing apparatus, and a basket used outside.

Conventional plasma processing equipment for manufacturing semiconductor devices has been used to process silicon single crystal thin films, silicon polycrystalline films, silicon dioxide (SiO ₂ ) films, and silicon nitride (Si ₃ N ₄ ) films on the surface of silicon semiconductor substrates (wafers). It is used in CVD (vapor phase growth) processes to form insulating films such as. This device is the first
It has a structure as shown in the figure. To process wafers using such a device, wafers 1' are placed vertically in a quartz tube 2' and lined up at regular intervals.
A reactant gas 3' is supplied, and positive and negative voltages (particularly high frequency voltages) are alternately applied to the wafer 1' to excite the plasma and heated in a heating furnace 4' to form the thin film on the surface of the wafer 1'. Let it happen. At this time, in order to uniformly generate a thin film on the surface of the wafer, a boat 6' is used which can hold the wafers together with the electrode plate 5' on which the wafers are mounted, arranged at regular intervals so that the wafers face each other. . The boat contains an electrode rod through which a high frequency voltage can be applied to the electrode plate and further to the wafer. The processed wafer is taken out from the quartz tube 2 onto the pedestal 7' along with the boat 6', transferred to a basket, and sent to the next process. This wafer transfer work is carried out on boat 5'.
Since the spacing between the wafers and the spacing between the grooves in the basket are generally different, they cannot be easily transferred. For this reason, conventionally, the wafers have been transferred manually using tweezers or the like, but this operation requires manual labor or has the disadvantage that the wafers may be damaged by the tweezers or the like. Therefore, automation of this work is desired. The present invention was devised based on this request.

Therefore, in the substrate transfer apparatus of the present invention, a boat for holding a substrate to be processed used in a processing apparatus,
A transfer device for transferring a substrate to be processed to and from a basket for transporting a substrate to be processed, which is used outside the device, and the transfer device includes a plurality of pairs of claws capable of gripping the substrate to be processed, and a plurality of pairs of claws capable of gripping the substrate to be processed, and A plurality of pairs of blocks attached to each other, a guide shaft passing through the blocks, a pantograph mechanism that can adjust the interval between the blocks on the guide shaft, and a pantograph mechanism that holds the pantograph mechanism and the guide shaft and that serves as a fulcrum. Therefore, it is characterized by comprising a pair of movable frames that are swingably supported so that the distance between the claws relative to each other can be varied.

Embodiments of the present invention will be described in detail below based on the accompanying drawings.

FIG. 2 shows a front view of the substrate transfer device according to the present invention, FIG. 3 shows a sectional view taken along the - line in FIG. 2, and FIG. 4 shows a sectional view taken along the - line in FIG. 2. . In each figure, reference numeral 5 denotes claws for gripping the wafer 1, and a plurality of pairs of claws are provided. Further, a groove 6 for holding the wafer 1 is formed at the tip thereof. This claw 5 is attached to a block 8 via an arm 7. This block 8 is adapted to be slidable on guide shafts 9, 9'. Therefore, this block 8 must have a certain width W in order to slide smoothly on the guide shafts 9, 9'.
Requires. If this width is larger than the wafer storage interval between the baskets, it becomes impossible to transfer wafers from one basket to another. Therefore, in this embodiment, an arm 7 is provided between the claw 5 and the block 8.
The length of this arm is gradually increased. However, making the arm 7 too long is disadvantageous in terms of strength and also increases the overall length of the device, so the blocks are divided into two groups to prevent the device from becoming too long. Therefore, two guide shafts 9, 9' are provided. The guide shafts 9, 9' are supported by a pair of movable frames 10, 10'. Movable frame 1
0 and 10' are pivotally connected to the fixed frame 12 by pins 11 and 11', respectively, and are attached to the press plate 13.
The distance between the pawls 5 relative to each other can be adjusted by rotation. The pressing plate 13 is driven up and down by a torsion shaft 15 screwed into a boss 14 attached to the fixed frame 12. Note that 16 in the figure is a shaft for supporting the pawl 5 so that it does not rotate around the guide shafts 9, 9'. In addition, in order to adjust the distance between the blocks 8 supporting the claws 5, a pantograph mechanism 17 is provided, in which a plurality of sets of equal length links are pivotally connected by pins, and is connected to each block 8 by its center pin 18. Further, this pantograph mechanism 17 is extended and contracted by rotation of a screw shaft 20 which is screwed into a nut 19 attached to the end of the pantograph mechanism 17 to adjust the distance between the blocks 8. A timing belt 21 is used so that the screw shafts 20 rotate in synchronism with each other. The timing belt 21 is tensioned and hung by a spring 22 in the middle. And pantograph 17
However, after the blocks 8 are set at predetermined intervals, the center pin 18 provided on the pantograph 17 is removed from the blocks 8, leaving the blocks 8 in a completely free state. (However, the left and right tuning mechanism is not shown in the drawings.) The operation of the transfer device of the present invention configured as described above will be described next. First, as shown in FIG. 5, rotate the screw shaft 15 clockwise to remove the pressure plate 1.
3 to open the movable frames 10, 10' and widen the distance between the opposing claws 5. At the same time, the pantograph mechanism 17 is driven to make the distance between adjacent claws the same as the distance between the wafers on the ball, and approximately between the wafers. Stop at the center position. In this state, the wafer 1, which has been subjected to plasma processing, is pulled out together with the boat 24 onto the tray 23 (see FIG. 2) below the apparatus. Next, as shown in FIG. 3, each claw 5 is moved in the direction of the arrow shown in FIG. 4 until it contacts the electrode plate 25 on the boat 24, and then the screw shaft 15 is rotated counterclockwise. to close the movable frames 10, 10'. In such a case, the claws 5 each insert the wafer 1 into the groove 6 at their tip.
When the device is pulled upward, the wafer 1 is separated from the electrode 25. Next, the pantograph mechanism 17 is operated until the spacing between the pawls becomes equal to the spacing between the baskets. In this state (see Fig. 6), if a basket is placed in place of the boat on the saucer and the screw shaft 15 is rotated clockwise to open the movable frames 10, 10', the wafer 1 will come off the claw 5 and fall. It will be stored in the basket. Note that the wafer storage spacing of commercially available baskets is 4.76 [mm], so if the thickness of the claws is set to 4.76 [mm], the spacing can be tightened until the claws are in close contact with each other, and the spacing dimension can be achieved with high precision. become. Further, transfer from the basket to the electrode plate can be realized by performing the above operation in reverse.

As explained above, the wafer transfer device of the present invention uses a plurality of pairs of claws with variable spacing to transfer wafers from a boat of a plasma processing device to a transport basket, or from a transport basket to a boat of a plasma processing device. This makes it possible to efficiently transfer materials, save labor in handling, and improve product quality.

In the above embodiments, a plasma processing apparatus was used as the processing apparatus.
Of course, the present invention can be applied regardless of the type of processing apparatus in cases where the wafers are mounted at different intervals on the transport basket and on the transport basket.

[Brief explanation of the drawing]

Fig. 1 is a schematic explanatory diagram of the plasma processing apparatus, Fig. 2
The figure is a front view of a substrate transfer device according to an embodiment of the present invention, and FIG. 3 is a sectional view taken along the line - in FIG.
Figure 4 is a sectional view taken along the - line in Figure 2;
The figure is a perspective view showing the movable frame opened, and FIG. 6 is a perspective view showing the movable frame closed and the spacing between the claws narrowed. In FIGS. 2 to 6, 1...wafer,
4...Boat, 5...Claw, 8...Block, 9,
9'... Guide shaft, 10, 10'... Movable frame.

Claims (1)

[Claims] 1 A transfer device that transfers a substrate to be processed between a boat for holding a substrate to be processed used within a processing device and a basket for transporting a substrate to be processed used outside the device, which A pantograph that includes a plurality of pairs of claws capable of gripping a substrate, a plurality of pairs of blocks to which the claws are attached, a guide shaft passing through the blocks, and an interval between the blocks on the guide shaft. A mechanism, and a pair of movable frames that hold the pantograph mechanism and the guide shaft and are swingably supported by a fulcrum to make the distance between the claws variable. A substrate transfer device.