JP3124393B2 - Wafer carrier transfer equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer carrier transfer apparatus for transferring a wafer carrier containing a wafer to a predetermined place in an automatic semiconductor wafer transfer system in a semiconductor manufacturing factory.

[0002]

2. Description of the Related Art Generally, a so-called automatic transfer system, which eliminates the intervention of a worker serving as a dust generation source, is introduced as a means for transferring a wafer carrier in a semiconductor manufacturing factory. This automatic transfer system is mainly composed of a transfer vehicle that transfers a wafer carrier containing a wafer to each process, and a transfer machine that transfers the wafer carrier received from the transfer vehicle to a predetermined location. An example of this type of wafer carrier transfer apparatus is disclosed in Japanese Utility Model Laid-Open No. 62-80334 by the present applicant.

FIG. 5 is a perspective view for explaining the conventional wafer carrier transfer apparatus. In the figure, reference numeral 50 denotes a guide member, and the guide member 50 is supported by suspension bolts suspended from a ceiling (not shown). The guide member 50 forms a transport path R, and a transport vehicle (not shown) travels on the transport path R. Further, a swingable mounting arm 51 is attached to the carrier, and a wafer carrier 52 is mounted on the mounting arm 51. On the other hand, 53 in the figure is a transfer machine,
The transfer machine 53 is installed on the floor of a building. A transfer arm 54 that can move up and down is attached to the transfer machine 53.
Is transferred to a predetermined location.

Next, the operation of the above-mentioned conventional transfer device will be described. First, in a state where the wafer carrier 52 is mounted on the mounting arm 51, a transport vehicle (not shown) is stopped at a predetermined position on the transport path R. Next, the mounting arm 51 is
By turning 90 degrees in the direction of the arrow, the arrangement state shown in FIG. 5 is obtained. Subsequently, the transfer arm 54 of the transfer machine 53 is raised to transfer the wafer carrier 52 from the mounting arm 51 to the transfer arm 54. Thereafter, the mounting arm 51 is turned in the opposite direction to the previous direction, and the transfer arm 54 is lowered to the lowest position to transfer the wafer carrier 52 onto the mounting table 55. Conventionally, the transfer operation of the wafer carrier has been performed by the above procedure.

[0005]

However, in the above-mentioned conventional transfer apparatus, a transfer machine (not shown) running on a transfer path R connected to a ceiling portion is provided with another transfer machine. Because 53 is installed on the floor, the transport vehicle on the transport path R and the transfer machine
3, there is a problem that relative displacement occurs, which lowers the transfer accuracy of the wafer carrier 52.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and has as its object to provide a wafer carrier transfer apparatus which can eliminate a decrease in transfer accuracy due to a dimensional change of a building over time. .

[0007]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and comprises a transport path connected to a ceiling of a building, a transport vehicle traveling on the transport path, A transfer arm mounted on the floor of a building; a transfer arm mounted on the floor of the building; and a transfer arm mounted on the transfer machine. In a wafer carrier transfer device in which the transfer of a wafer carrier is performed between the transfer arm and a transfer arm, first sensor means for detecting a separation distance between the transfer vehicle and the transfer machine is provided,
The advance / retreat position of the mounting arm with respect to the transfer machine can be controlled based on the detection result from the first sensor means,
Second sensor means for detecting the traveling position of the transport vehicle is provided, and the stop position of the transport vehicle on the transport path can be controlled based on the detection result from the second sensor means.

[0008]

In the apparatus for transferring a wafer carrier of the present invention, the position of the mounting arm with respect to the transfer machine is controlled based on the detection result from the first sensor means, and the detection from the second sensor means is performed. By controlling the stop position of the transfer vehicle on the transfer path based on the result, the delivery arm of the transfer vehicle and the transfer arm of the transfer machine are always in the same arrangement state when transferring the wafer carrier. As a result, the wafer carrier is always transferred to a fixed position without causing positional variation.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a wafer carrier transfer apparatus according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic plan view illustrating an embodiment of the present invention, and FIG. 2 is a schematic side view of the same. In the figure, reference numeral 1 denotes a guide member, and the guide member 1 is supported by a pair of left and right suspension bolts 3 suspended from a ceiling 2 portion. The guide member 1 has a hollow structure having a rectangular cross section, and the hollow portion forms a transport path R.

The transport path R is provided between the respective steps, and the transport vehicle 4 runs on the transport path R. Further, a mounting arm 5 having a substantially U-shape in plan view is attached to the transporting vehicle 4.
The structure is such that it can turn in the direction of the arrow and move back and forth in the direction of the arrow C.

On the other hand, reference numeral 6 in the figure denotes a transfer machine, which is installed on the floor (not shown) of the building. The transfer machine 6 is provided with a transfer arm 7 which can be moved up and down. The wafer carrier 8 carried by the carrier 4 is transferred to a predetermined location by the transfer arm 7. .

In the wafer carrier transfer apparatus of the present embodiment, first, first sensor means for detecting a separation distance between the transfer vehicle 4 and the transfer vehicle 6 is provided. The first sensor means comprises, for example, an L-shaped reflector 9 and a lightwave or ultrasonic distance sensor 10. One reflector 9 is attached to the front right side of the transfer machine 6. The other distance sensor 10 is attached to the tip of the left arm 5a of the mounting arm 5. The reflection plate 9 and the distance sensor 10 are arranged to face each other in a state where the mounting arm 5 on which the wafer carrier 8 is mounted is turned as shown in FIG.

Further, in the present embodiment, second sensor means for detecting the traveling position of the transport vehicle 4 on the transport path R is provided. This second sensor means is constituted by, for example, an L-shaped slit plate 11 and a reflection type optical sensor 12, and one slit plate 11 is provided on the opposite side of the above-mentioned reflection plate 9,
That is, the optical sensor 12 is attached to the front left side of the transfer machine 6, and the other optical sensor 12 is attached to the tip of the right arm 5 b of the placing arm 5. The slit plate 11 and the optical sensor 12
As in the case of the first sensor means, the mounting arms 5 on which the wafer carriers 8 are mounted are arranged so as to face each other in a state of turning as shown in FIG.

The detection results from the first and second sensor means are transmitted to a control unit (not shown). Then, based on the detection results from the respective sensor means, the control unit controls the advance / retreat position of the mounting arm 5 with respect to the transfer machine 6 and the stop position of the transport vehicle 4 on the transport path R.

In the configuration of the above embodiment, the reflecting plate 9 and the slit plate 11 are mounted on the transfer machine 6 side, and the distance sensor 10 and the optical sensor 11 are mounted on the carrier 4 side, that is, on the mounting arm 5. However, the present invention is not limited to this. That is, the reflection plate 9 and the distance sensor 10 and the slit plate 11 and the optical sensor 12 are attached to one or the other of the transport vehicle 4 and the transfer machine 6 while satisfying the above-described arrangement conditions. Just do it.

Next, the operation of the transfer apparatus according to the present embodiment will be described with reference to the flowchart of FIG. First, when the transfer of the wafer carrier 8 from the carrier 4 to the transfer machine 6 is performed, the transfer arm 7 is set at a predetermined height, that is, Arm 5
It is made to stand by at a height that is lower than that and does not cause a collision when the mounting arm 5 turns (S1). Subsequently, with the wafer carrier 8 mounted on the mounting arm 5, the transport vehicle 4 on the transport path R is moved to a position where teaching has been performed in advance (S2).

Next, the mounting arm 5 of the carrier 4 is turned by 90 degrees (S3). At this time, the reflection plate 9 and the distance sensor 10 as the first sensor means are in the facing state as shown in FIG. 1, and from this state, the separation distance between the carrier 4 and the transfer machine 6 is determined by the distance sensor 10. It is detected (S4). Here, the separation distance between the transport vehicle 4 and the transfer machine 6 is detected based on the lapse of time until the laser light or ultrasonic wave emitted from the distance sensor 10 hits the reflecting plate 9 and returns to the distance sensor 10 again. The detection result is sent from the distance sensor 10 to the control unit.

The control unit compares the reference distance data stored in advance with the detection data from the distance sensor 10 and moves the mounting arm 5 forward and backward so that the two data values match (S5). Thereby, the position of the mounting arm 5 with respect to the transfer machine 6 is controlled.

At the above time, the slit plate 11 and the optical sensor 12, which are the second sensor means, are arranged as follows. That is, as shown in FIG. 3, assuming that the traveling direction of the transport vehicle 4 is the D direction, the optical axis focal position P of the optical sensor 12 is substantially the same height as the slits 11 a provided at regular intervals on the slit plate 11. And slit 11a
Is placed in a state where no passage has been made.

From such an arrangement state, the transport vehicle 4 starts traveling at a slow speed at a low speed (S6). At this time, the optical axis focal position P of the optical sensor 12 shifts sequentially in the direction D (FIG. 3), and accordingly, the optical sensor 12
A pulse signal corresponding to the number of passages a is transmitted to the control unit.

The control section sequentially receives pulse signals from the optical sensor 12 (S7), and determines whether or not the number of pulses has reached a preset number of pulses (S8). Then, at the same time when the number of input pulses reaches the predetermined number, the traveling speed of the carrier 4 is stopped (S9). Thereby, the stop position of the transport vehicle 4 on the transport path R is controlled.

Subsequently, the transfer arm 7 of the transfer machine 6 is raised to transfer the wafer carrier 8 on the mounting arm 7 to the transfer arm 7 (S10), and the mounting arm 7 is moved to the previous position. Is turned in the opposite direction to return to the original position (S1
1). Thereafter, the transfer arm 7 is lowered to the bottom, and the wafer carrier 8 is transferred to a predetermined location (S12). With the above procedure, the transfer operation of the wafer carrier 8 is completed.

As described above, in the transfer device of the present embodiment, the position of the mounting arm 5 with respect to the transfer machine 6 is controlled based on the detection result from the first sensor means, and the second sensor means is controlled. By controlling the stop position of the transport vehicle 4 on the transport path R on the basis of the detection result from the vehicle, the relative positional shift between the transport vehicle 4 and the transfer machine 6 due to the dimensional change of the building over time. When the wafer carrier 8 is delivered, the mounting arm 5 of the carrier 4
And the transfer arm 7 of the transfer machine 6 can always be in the same arrangement state. Therefore, if the wafer carriers 8 are transferred under such an arrangement state, the individual wafer carriers 8 are always transferred to a fixed position without causing positional variation.

In this embodiment, the case where the wafer carrier 8 is transferred from the transfer vehicle 4 to the transfer machine 6 has been described. However, by inverting the above-described transfer procedure,
Delivery from the transfer machine 6 to the carrier 4 is also easily possible.

[0025]

As described above, according to the transfer apparatus of the present invention, even when a relative displacement occurs between the transfer vehicle and the transfer machine, the transfer of the wafer carrier can be performed. In this method, the placement arm of the carrier and the transfer arm of the transfer machine can always be in the same arrangement state. As a result, the wafer carrier is always transferred to a fixed position without causing positional variation, so that a decrease in the transfer accuracy due to a temporal change in the building is eliminated, In an automatic transfer system at a semiconductor manufacturing plant,
Higher precision wafer carrier transfer can be expected.

[Brief description of the drawings]

FIG. 1 is a schematic plan view illustrating an embodiment of the present invention.

FIG. 2 is a schematic side view illustrating an embodiment of the present invention.

FIG. 3 is a perspective view for explaining a second sensor means.

FIG. 4 is an operation flowchart of the apparatus in the embodiment.

FIG. 5 is a perspective view illustrating a conventional transfer device.

[Explanation of symbols]

 2 ceiling 4 transfer vehicle 5 mounting arm 6 transfer machine 7 transfer arm 8 wafer carrier 9 reflection plate 10 distance sensor 11 slit plate 12 optical sensor R transfer path

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/68 B65G 47/52 101 B65G 49/07

Claims (3)

(57) [Claims] 1. A transport path connected to a ceiling of a building, a transport vehicle traveling on the transport path, a mounting arm attached to the transport vehicle, and a transport arm mounted on a floor of the building. A transfer device, and a transfer arm attached to the transfer device, wherein a wafer carrier is transferred between a transfer arm of the transfer vehicle and a transfer arm of the transfer device. The transfer device according to the above, further comprising first sensor means for detecting a separation distance between the carrier and the transfer machine, and based on a detection result from the first sensor means, And a second sensor for detecting a traveling position of the carrier, and a second sensor for detecting a traveling position of the carrier, and the carrier on the carrier path based on a detection result from the second sensor. Controllable stop position Apparatus for transferring a wafer carrier, wherein the door. 2. The apparatus according to claim 1, wherein the first sensor is a reflector mounted on one of the carrier and the transfer device, and a distance sensor mounted on the other corresponding to the reflector. 3. The wafer carrier transfer device according to claim 1, wherein: 3. The optical sensor according to claim 2, wherein said second sensor means includes a slit plate attached to one of said carrier and said transfer device, and an optical sensor attached to said other corresponding to said slit plate. 3. The wafer carrier transfer device according to claim 1, wherein: