JPS6145381B2 - - Google Patents

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a semiconductor wafer manufacturing process for transferring a large number of semiconductor wafers housed in one cassette to another cassette made of different materials. The present invention relates to a wafer transfer device.

[Prior art]

A conventional semiconductor wafer (hereinafter referred to as "wafer") transfer apparatus has the configuration shown in FIG. 1 as a front view of the main parts. Reference numeral 1 designates one cassette, in which a large number of wafers 3 are stored in parallel rows at intervals in a large number of storage grooves 1a that are provided in parallel in the vertical direction facing the inner surfaces of both sides. Since cassette 2 is used in a different processing step from cassette 1, it is the other cassette made of a different material, and is provided with a large number of storage grooves 2a in parallel to the vertical direction facing the inner surfaces of both sides, and a large number of wafers 3 can be stored in the cassette 2. are being relocated and stored. 4 is a base plate on which cassettes 1 and 2 are placed parallel to each other with an interval between them. Reference numerals 5 and 6 denote a pair of wafer lifting tools, each of which has a large number of receiving grooves 7a on the arc-shaped inner surface of the receiving tray 7, so that it can receive and support a large number of wafers 3 all at once from below. , the saucer 7 is fixed to the upper end of the support rod 8,
The support rod 8 is supported by a lower vertical drive means (not shown) and is configured to be moved up and down.

Next, reference numerals 9 and 10 denote a pair of clamping tools facing each other on both sides, which have a large number of retaining grooves 9a and 10a on their arcuate inner surfaces.
is provided to clamp and hold a large number of wafers 3 at once. The rear ends of the clamping tools 9 and 10 are supported by a support member (not shown), and the distance between the two can be widened or narrowed by a variable means (not shown). The support member is moved left and right by a traversing means (not shown), and the clamping tools 9 and 10 are moved together.

Wafer transfer using the conventional transfer apparatus described above is performed as follows. A large number of wafers 3 are stored in one cassette 1. First, the push-up tool 5 is raised in the direction of arrow A, and the receiving tray 7 collectively receives and supports each wafer 3 from below, and the wafers 3 are pushed up above the cassette 1 to the positions of the clamping tools 9 and 10. Next, the variable means is actuated to narrow the clamping tools 9 and 10 in the directions of arrows B and C to clamp and hold each wafer 3 at once. The push-up tool 5 is lowered, the traversing means is activated, and the clamping tools 9 and 10 are moved in the direction of arrow D while gripping the wafer 3 through the support member, and are brought to the center of the other empty cassette 2. At this time,
The push-up tool 6 is raised and the tray 7 is placed on standby above the cassette 2. Here, the receiving tray 7 is slightly raised by the push-up tool 6, and each cassette 2 is received from below at once. Subsequently, the variable means is actuated to spread the clamping tools 9 and 10 as shown by arrows E and F, and each wafer 3 is received by the receiving tray 7. Push up tool 6 with arrow G
The wafers 3 are lowered as shown in FIG. Through this series of operations, the wafers 3 in one cassette 1 are transferred to the other cassette 2.

In the above-mentioned conventional device, the raising and lowering of the push-up tool 5,
The clamping tools 9 and 10 had to be clamped, the clamping tools 9 and 10 had to be clamped, the clamping tools 9 and 10 had to be clamped, the clamping tools 9 and 10 had to be moved laterally, and the push-up tool 6 had to be moved up and down, and the transfer took too much time. In an actual example, it took about 30 seconds to transfer 25 wafers. In addition, since there are many moving parts, dust is likely to be generated, and there is a risk that it will adhere to the wafer 3. Furthermore, the structure is complicated and the external shape is large due to the lateral movement means for the pair of clamping tools 9 and 10 and the vertical movement means for the push-up tables 5 and 6.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the above-mentioned conventional device, and includes a pair of holders on both sides of the base plate, and a rotating arm on the rear end side of the center of the base plate at the lower part. It is rotatably supported, and a pair of clamping tools are supported at variable intervals on the front part of the rotating arm, and a cassette containing a large number of wafers is placed over one of the holders from above. and lower the wafers onto the base plate, receive the wafers all at once on the tray at the top of the cassette, lift it above the cassette, cover the other empty cassette with the other tray, and lower the wafers onto the base plate. Rotate the rotating arm toward one cradle, clamp both sides of the wafer using a pair of clamping tools, and hold the wafer together. Rotate the rotary arm toward the other cradle and place the wafer on the other cradle. The wafers are received all at once on a tray on the top of the table, the pair of clamping tools are spread out, the rotating arm is rotated back to its original position, and the other cassette is lifted to store the wafers all at once. In this way, the wafer can be quickly moved by the rotation of the movable arm, reducing the transfer time, reducing the number of moving parts, generating less dust, reducing wafer contamination, and simplifying the structure. The purpose of this invention is to provide a semiconductor wafer transfer device.

FIG. 2 is a perspective view of a transfer device according to an embodiment of the present invention, and 1 to 3, 1a, and 2a are the same as the conventional device. 20 is a base plate on which one cassette 1 and the other cassette 2 are placed with an interval between them. 21 and 22 are one pedestal and the other pedestal, both of which are parallel to each other with a predetermined spacing between them.
A receiving tray 23 is fixed to a supporting member 24 on both sides of the top, and the receiving tray 23 is at the height of the upper part of the inside of the cassettes 1 and 2. A large number of receiving grooves 23a having the same pitch as the receiving grooves 1a and 2a of the cassettes 1 and 2 are provided on the upper surface of the receiving tray 23, so that a large number of cassettes 3 are received and supported all at once from below in a parallel state. There is. 25 is a support plate fixed to the base plate 20 at the rear end position in the center between the pair of pedestals 21 and 22; 26 is a rotating electric motor attached to the rear of this support plate 25; is extended to the front and is located on the center line between the pedestals 21 and 22 (a line at a distance L from both pedestals 21 and 22). 27 is a rotating arm whose lower part is fixed to a shaft end 26a, and whose upper part is rotated about 90 degrees to the left and right about this shaft end 26a; 28 and 29 are a pair of upper and lower clamping tools, which are opposed to each other; A large number of retaining grooves 28a, 29a are provided on the inner surface of the cassettes 1, 2 at the same pitch as the housing grooves 1a, 2a of the cassettes 1, 2. The arms are separated by a distance and are supported on the upper part of the rotating arm 27 in a variable manner. 30 is a cam rotating electric motor fixed to the rear part of the rotating arm 27, and the shaft end 30a passes through point Q and extends forward; 31 is a cam fixed to the shaft end 30a and having an oval outer circumference; It is in contact with the inner surfaces of the pair of clamping tools 28 and 29, and can be opened and closed by approximately 10 mm by rotating through 90 degrees.

The wafer 3 is transferred by the apparatus of the above embodiment as follows. First, a large number of wafers 3
One cassette 1 containing the
1 as a guide for the inside and lower it onto the cover base plate 20.
The tray 23 of the tray 21 is located at a height above the cassette 1, and the wafers 3 are received all at once above the cassette 1. Here, when the rotating arm 27 is rotated 90 degrees toward the pedestal 21 side as shown by the arrow H by the electric motor 26, the pair of clamping tools 28 and 29 are positioned on both sides of the center height of each wafer 3 (dotted chain line). ). At this time, the gap between both clamping tools 28 and 29 is about 20 mm wider than the diameter of the wafer 3. Subsequently, the cam 31 is rotated 90 degrees by the electric motor 30 to narrow the gap between the clamping tools 28 and 29, and a large number of wafers 3 are clamped and held at once. Next, when the rotating arm 27 is rotated by the electric motor 26 by 180 degrees toward the pedestal 22 as shown by the arrow J, the wafer 3 is placed in the position shown by the two-dot chain line, and each wafer 3 is placed on the pedestal 23 of the other pedestal 22. reach. Here, the electric motor 30
Rotate the cam 31 by 90 degrees and attach both clamping tools 2.
8 and 29, and place each wafer 3 on the tray 23.
into the receiving groove 23a. With the clamping tools 28 and 29 spread out, the rotating arm 27 is rotated by 90 degrees as shown by arrow K by the electric motor 26, and returned to the original position shown by the solid line. Next, when the cassette 2 is lifted, the wafers 3 on the tray 23 are all stored in the cassette 2, and the transfer is completed. In this way, wafers 3 can be transferred quickly. According to actual measurements, 25 sheets could be transferred in 10 seconds.

In the above embodiment, the cassette 1 containing the wafers 3 was placed on the side of the pedestal 21;
It is also possible to place an empty cassette 2 on the receiving stand 21 side and transfer it.

Further, in the above embodiment, the electric motor 30 and the cam 31 are used as variable means for opening and closing the pair of clamping tools within a predetermined range, but an electromagnetic device or a pneumatic cylinder may also be used.

Furthermore, as a means for rotating the rotating arm 27, although the rotating electric motor 26 is used in the above embodiment, the present invention is not limited to this, and a mechanism using an electromagnetic device or a pneumatic cylinder may be used.

〔Effect of the invention〕

As described above, according to the present invention, a pair of pedestals are disposed in parallel on both sides of the base plate, and one cassette containing a large number of wafers is placed over the one pedestal, and the pedestal is placed on the base plate. Place the wafers in a batch on the tray at the top of the pedestal so that the cassette is positioned above the cassette, place the other empty cassette over the other pedestal, lower the wafers onto the base plate, and place the wafers in the middle of the base plate. A rotating arm whose lower part is supported on the end side is rotated toward one of the pedestals, and a pair of clamps supported at a variable interval on the upper part of the rotating arm is used to hold the wafer on one of the pedestals. The wafers are clamped and held together from both sides, the rotating arm is rotated to the other pedestal side, the wafer is received all at once on the tray of the other cradle, and the pair of clamping tools are spread out and the rotating arm is held. Since the cassette is rotated back to its original position and the other cassette is lifted to store the wafers all at once, the time for transferring wafers is shortened and the structure is simple and inexpensive. In addition, since there are fewer moving parts, less dust is generated, the area of contact between the clamping tools is reduced, and contamination of the wafer is reduced.

[Brief explanation of the drawing]

FIG. 1 is a front view showing essential parts of a conventional wafer transfer apparatus, and FIG. 2 is a perspective view of a wafer transfer apparatus according to an embodiment of the present invention. 1, 2...cassette, 1a, 2a...storage groove, 3...wafer, 20...base plate, 21, 22
... cradle, 23... saucer, 23a... receiving groove,
24... Support member, 25... Support plate, 26... Rotating electric motor, 26a... Shaft end, 27... Rotating arm,
28, 29... Clamping tool, 28a, 29a... Holding groove, 30... Cam rotation electric motor, 30a... Shaft end, 31... Cam. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] 1. Receiving grooves having the same pitch as the accommodating grooves provided in the cassette are provided on the arcuate upper surface, and receiving trays for receiving a large number of wafers from below are fixed to the upper part of the base plate. A pair of pedestals fixed in parallel on both sides of the top, with the lower part supported at the center rear end side of the base plate, and the upper part supported by a rotating means to one of the pedestals and the other pedestal. A rotating arm that rotates upward, both of which are supported at a predetermined interval above the rotating arm, are supported at variable intervals, and extend parallel to each other in front, and a groove for accommodating the cassette is formed on the opposing inner surface. a pair of clamping tools each provided with a large number of holding grooves of the same pitch; and a variable means attached to the rotating arm to open and close the spacing between the clamping tools within a predetermined range; Place one cassette containing several wafers over the one receiver from above and lower it onto the base plate, receive the wafers all at once on the receiver tray, and position the cassette above the cassette;
Place the other empty cassette over the other pedestal and lower it onto the pedestal, rotate the rotating arm above the one pedestal, and place the pair of clamping tools on both sides of the wafer. Then narrow the gap between both clamping tools to clamp and hold the wafers all at once, and rotate the rotating arm above the other holder to place the held wafers all at once onto the other holder. The wafers on the tray are stored in the cassette all at once by opening both clamping tools, rotating the rotating arm back to its original position, and lifting the other cassette. Transfer equipment for semiconductor wafers. 2. The semiconductor wafer transfer apparatus according to claim 1, wherein the rotating means comprises an electric motor. 3. The variable means includes an electric motor attached to the rear part of the rotating arm, and is fixed to the shaft end of this electric motor, and the elliptical outer periphery is in contact with the inner surface of a pair of clamping tools, and the variable means has an electric motor attached to the rear part of the rotating arm. 2. The semiconductor wafer transfer device according to claim 1, further comprising a cam that alternately narrows and widens the distance between the two clamping tools within a predetermined range by rotation.