JPH0650757B2 - Wafer transfer device - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a wafer transfer apparatus having improved wafer transfer means for sending an unprocessed wafer to a processing step in a semiconductor wafer manufacturing line and storing a processed wafer. It is about.

[Background of the Invention] In a conventional semiconductor wafer manufacturing line, a wafer transfer device for transferring and storing unprocessed and processed wafers is configured as shown in Figs. 6 to 9, for example.

FIG. 6 shows an apparatus in which the wafer is linearly transferred on a plane. The unprocessed wafer 11 is sent out from the supply jig 2a and sent to the main unit 200 by the transfer belt 30a. The wafer processed in the main unit 200 is stored in the storage jig 3a or 3b by the transfer belt 30b. With this method,
The inlet and the outlet of the wafer are provided one on each of the two side surfaces of the main device 200 facing each other.

FIG. 7 shows an apparatus for transferring a wafer in a U-shape on a plane. The wafer 11 is sent from the supply jig 2a,
After being sent to the main device 200 by 30a and processed in the main device 200, the storage jig 3a is conveyed by the conveyor belt 30b.
Is stored in. In this method, a wafer outlet and an inlet are provided on the same side surface of the main device 200.

FIG. 8 shows an apparatus of a system for transferring a wafer in a U-shape on a plane as in the above case, in particular, two jigs 2a and 2b are
It is a device that can be used as either a supply jig or a storage jig. When the jig 2a is used as the supply jig and the jig 2b is used as the storage jig, the wafer 11 supplied from the supply jig 2a is used.
Is transported to the main device 200 by the transport belt 30, processed, and then transported to the storage jig 2b by the transport belt 30. When the jig 2b is used as the supply jig, the wafer 11
Is sent to the main device 200 by changing its direction at a right angle in the side path 30c on the way by the conveyor belt 30. Then, the wafer 12 that has been processed in the main device is transported to the storage jig 2a by the transport belt 30 again changing the direction to the right angle in the side path 30c. In this method, the direction of the transfer path can be changed, and the transfer path of the wafer can be changed to a right angle on the way.

FIG. 9 shows a transfer device of a type that transfers wafers in a U-shape on a plane.
It is applied when it is premised that the number of wafers stored in the jig 2a is larger than that of the jigs 2a. Here, the jigs 2a, 2b, ... Are arranged in a line, and the wafer 11 is first supplied from the leading jig 2a and conveyed to the main device 200 by the conveyor belt 30a. jig
The jig 2a supplied with all the wafers 11 from 2a moves to the 2x position, and is in a position to receive the wafers 12 processed in the main apparatus 200. The processed wafer 12 is then stored in the jig 2a by the transfer belt 30b. Subsequent jig 2
Repeat the supply and storage for a, 2b ...

[Problems of Background Art] What is desired in a wafer transfer apparatus is that wafers are continuously processed without stopping the main apparatus even during replacement of a supply jig in order to improve work efficiency. . However, the main device must be stopped during the replacement of the supply jig in the examples of FIGS. 6 to 8 and when the jig 2a is moved to the 2x position in the example of FIG. .

In addition, it is desirable to use the same jig for the supply jig and the storage jig in order to manage the lots of the wafers. However, in the examples of FIGS. There is a risk of contamination.

In the example of FIG. 9, there is no problem of mixing of lots, but since the number of wafers stored in the supply jig must be smaller than the number of wafers stored in the main device, the jigs that can be used are limited. Further, in the example of FIG. 6, the wafers are supplied from a plurality of jigs, but the priority order of each jig depends on the arrangement order of the jigs, so that it is not possible to determine an arbitrary priority order among the jigs.

Further, in the example of FIG. 8, the forward path and the return path of wafer transportation partially overlap, and there is a possibility that the wafers may collide with each other. As a preventive measure, it is necessary to control the supply of the wafer 11 from the supply jig and the discharge of the processed wafer 12 from the main device by separate operations, but this causes the index down of the transfer. .

Furthermore, the number of robots required should be small when unmanned in the process. In the example of FIG. 6, since the supply jig and the storage jig are on both sides of the main unit, two inter-process transfer robots for receiving the inter-process jig are required.

[Object of the Invention] In view of the above problems, an object of the present invention is to supply a wafer,
The same jig can be used for storage, and wafers are supplied and stored and transferred continuously without stopping the main unit. Also, by selecting the jig priority order, the wafers can be randomly transferred. It is an object of the present invention to provide a wafer transfer device that can perform various transfers and can perform lot management for each jig when unmanned or automated.

[Outline of the Invention] That is, a wafer transfer apparatus according to the present invention is configured by disposing a plurality of jigs for accommodating unprocessed and processed wafers with respect to a main apparatus that performs wafer processing. Each of the jigs has a supply port for sending an unprocessed wafer to the main device and a storage port for receiving a processed wafer, and the supply port of each of the jigs has a cross pattern or a partial three-dimensional intersection. The wafer carry-in port of the main device is connected through the wafer transfer passage network, and the wafer transfer outlet of the main device is connected to the storage port of each jig through the wafer transfer passage network. To do. By changing the wafer transfer passage network, the wafers are continuously supplied and housed without collision, and the jig priority order can be selected.

[Embodiment of the Invention] An embodiment of the present invention will be described with reference to FIGS. 1 and 2. In this example, the unprocessed wafer 11 has four jigs 21,
It shows the case where the processed wafers are supplied from 22, 23, and 24, and the processed wafers are stored again in the four jigs.

This device consists of a station part 100 and a buffer part 300.
And a main device 200.

The wafers 11 housed in the jigs 21, 22, 23, and 24 of the station portion 100 reach the transport passage 51 through the unique transport paths defined for these jigs. Then, from the exit of the transport passage network, through the transport forward route 60, the buffer portion 30
0, and the stocker jigs 71, 72, 7 unique to each jig
Transferred to 3, 74. Wafer 11 to buffer portion 300
For example, the order of supplying and transporting the jigs is set in units of jigs so that after all the wafers 11 of the jig 21 are sent out, the supply and transport of the wafers 11 of the jig 22 to the buffer portion 300 subsequent to the jig 21 are started. Then do. The starting order is set in advance. Then, this supply and transport operation is repeatedly executed.

The wafers thus stored in the stocker jigs 71 to 74 of the buffer portion 300 are supplied to the main device 200 from the wafer carry-in port of the main device in the same order as described above. Main device 200
The wafer processed in the inside reaches the transportation passage 43 through the transportation return passage 90 after exiting the wafer outlet of the main device. Then, it is always stored in the same jig as the starting jig from the entrance of the transport passage network. The transportation route is also a unique transportation route defined for each jig.

That is, the transport passages are provided in rows for each of the jigs 21 to 24, and the passages are commonly connected so as to form a grid-like passage network. The direction of the wafer can be changed at each intersection of this passage network. Here, the configuration of the transport passage network in this embodiment will be described.

In this case, the transport passage network is provided corresponding to the jig 21,
The transport passages 31 and 41 connected to the transport forward path 60 via the transport passage 51, and the transport passage 3 provided corresponding to the jig 22.
2, 42, the transportation path 33, 43 provided corresponding to the jig 23, connected to the transportation return path 90, the transportation path 34, 44, 54 provided corresponding to the jig 24, Transport passages 31, 32, 3
3, 34 and the transport passages 41, 42, 43, 44 are connected to each other in a grid pattern by connection passages, respectively,
While crossing the transportation return path 90 in three dimensions, the transportation path 54
And the transport forward path 60 are connected by a bypass passage via the transport passage 51. More specifically, the transport passages for the wafer 11 defined for the respective jigs 21-24 of the station portion 100, the stocker jigs 71-74 for the buffer portion 300, and the transport passages for the processed wafers will be described below. Will be explained.

Wafer 1 stored in the jig 21 of the station part 100
1 is transferred to the jig 71 of the buffer portion 300 via the transport passages 31, 41, 51, 61. The wafer 11 is further transported through the transportation passage 81.
Passing through and being processed in the main unit 200, the transport passages 43, 4
After passing through 2, 41 and 31, they are stored again in the original jig 21.

Wafer 1 stored in jig 22 of station part 100
1 is transferred to the jig 72 of the buffer portion 300 via the transport passages 32, 31, 41, 51, 61, 62. The wafer 11 further passes through the transfer passages 82 and 81 to be processed in the main device 200,
It is again stored in the original jig 22 via the transport passages 43, 42, 32.

Wafer 1 stored in jig 23 of station part 100
1 is transferred to the jig 73 of the buffer portion 300 via the transport passages 33, 32, 31, 41, 51, 61, 62, 63. Wafer 11
Further passes through the transport passages 83, 82, 81 to be processed in the main device 200, passes through the transport passages 43, 33, and again returns to the original jig 23.
Is stored in.

Wafer 1 stored in jig 24 of station section 100
1 is transferred to the jig 74 of the buffer portion 300 via the transport passages 34, 44, 54, 51, 61, 62, 63, 64. Wafer 11
Further passes through the transport passages 84, 83, 82, 81 to the main unit 200
After being processed inside, it is stored again in the original jig 24 via the transport passages 43, 44, 34.

When a jig collects all the processed wafers, the jig that collects the wafers is replaced with the jig that houses the unprocessed wafer 11. Then, the supply is started in the set order again.

For example, if the supply order of the jigs of the station portion 100 is determined to be the jigs 21-22-23-24, the jig 21 that has finished storing wafers is the jig that has stored new unprocessed wafers 11. And is set at the position of the jig 21. When the wafer 11 of the jig 24 set in the position of the jig 21 is transferred to the jig 74 of the buffer portion 300, the transfer of the wafer 11 to the jig 71 is continuously started. . In this way, the wafers are continuously supplied, processed, and stored without stopping the main device 200.

However, in the above-described wafer flow, the transport path of the unprocessed wafer 11 from a certain jig and the transport path for storing the processed wafer to another jig may intersect or partially overlap. There are cases. In that case, the unprocessed wafer 11 and the processed wafer may collide with each other. Therefore, one transportation path is changed to an appropriate path so that there is no such intersection or overlap.

Here, there is a possibility that the wafers may collide with each other due to intersections or overlaps of the transportation paths in the following cases. First, the wafer 11 starting from the jig 21 of the station portion 100 is processed in the main unit 200, passes through the passages 43, 42, 41, 31 and then the jig 2
Wafer 1 from jig 22 or jig 23 while being stored in 1
This is the case when 1 comes out.

In the former case, the transfer path of the wafer 11 supplied from the jig 22 is changed so that the transfer paths 32, 33, 34, 44, 54, 51, 61, 62 are transferred.
In the latter case, the carrying path of the wafer 11 supplied from the jig 23 is changed so that the carrying paths 33, 34,
It suffices to pass through 44, 54, 51, 61, 62 and 63.
Further, the wafer 11 that has started from the jig 22 of the station portion 100 has been processed in the main device 200 and has been transported through the transportation passages 43, 42, 3.
If the unprocessed wafer 11 comes out of the jig 23 while being stored in the jig 22 via 2, the carrying path of the wafer 11 supplied from the jig 23 is changed to the carrying path 33. , 34, 44, 54, 5
It suffices to pass through 1, 61, 62 and 63.

In this way, wafer supply and storage from each jig
It can be performed continuously without wafer collision.

Since this apparatus supplies and stores wafers from the same jig, lot management can be performed for each jig.
Also, when transporting jigs within a process or between processes, the number of transport robots introduced can be reduced because the jigs are concentrated on one side. In the case of using the transfer robot, if the robot is installed so as to be movable in the direction of arrow a, one robot can transfer a plurality of jigs.

Further, by providing the buffer portion, even if the number of wafers stored in the main device is smaller than the number of wafers stored in the jig in the station portion, the jig in the station portion can store processed wafers at any time. Specifically, first, the wafer 11 of each jig is sent to the stocker jig of the buffer portion 300 that can store all of them. The stocker jig of the buffer portion 300 sends only a suitable amount of wafers to the main device 200 to the main device 200. Therefore, when the processed wafer is stored in the original jig, the unprocessed wafer never remains there. When the number of wafers accommodated in the main device is larger than the number of wafers accommodated in the jig in the station portion, it is not necessary to use this buffer portion 300.

As described above, it suffices to decide whether to install or not install the buffer part 300 according to the number of wafers stored in the main device 200, and even if the buffer part 300 is installed, remove it from the transport path when it is not needed. Therefore, the size and price of the entire device can be considered.

FIG. 3 shows station parts 100 and 101 in which a replacement jig is arranged in the center and both sides of which have the same transport path as in FIG.
And buffer parts 300 and 301 similar to those in FIG. 1 are arranged, and main devices 200 and 201 are arranged on both sides thereof. Here, the wafers that have been processed in one of the main devices are collected in a central jig, and are continuously supplied to the other main device, processed, and then collected in the central jig again. The functions of both station parts and both main devices are similar to those of the device of FIG. The jig that has finished storing the wafer is transported to the next step as indicated by an arrow b. This transportation may be performed using a transportation robot. Thus, by arranging the station portion, the buffer portion and the main device on both sides of one jig, two kinds of processing can be performed without moving the jig. It is also easy to configure the jigs to be transferred between the devices.

FIG. 4 is a diagram showing a station portion of the embodiment when there are two jigs. Here again, as in FIG. 1, the wafer 11 starting from each jig is sent to the buffer part and the main device part by the carrying path peculiar to each jig, and further passes through the carrying path peculiar to the starting jig. , It is stored again in the original jig.
The wafer transfer sequence and the presence / absence of the buffer portion are the same as those in the embodiment of FIG.

In the case of FIG. 4, the transportation path of the wafer 11 and the transportation path of the wafer which has been processed are determined for each jig in the station part as follows.

The wafer 11 stored in the jig 25 is sent to the buffer part through the transfer passages 35 and 45, further processed in the main unit, and then again returned to the original cure via the transfer passages 35a and 35. Tool 25
Is stored in.

The wafer 11 stored in the jig 26 is transferred to the transportation paths 36, 46,
After being sent to the buffer portion via 45 and further processed in the main unit, they are again stored in the original jig 26 via the transport passages 35a and 36.

In the case of the present embodiment, since the transfer passages 35 and 35a function as connection passages and the transfer passages 45 and 46 function as bypass passages, there is no case where the wafers collide with each other. Need not be changed.

FIG. 5 is a diagram showing the station portion of the embodiment when there are three jigs. Here again, as in FIG. 1, the wafer 11 starting from each jig is sent to the buffer part and the main device part by the carrying path peculiar to each jig, and further passes through the carrying path peculiar to the starting jig. , It is stored again in the original jig.
The wafer transfer sequence and the presence / absence of the buffer portion are the same as those in the embodiment of FIG.

In the case of FIG. 5, the carrying path of the wafer 11 and the carrying path of the wafer which has been processed are determined for each jig in the station part as follows.

The wafer 11 stored in the jig 27 is transferred to the transport passages 37, 47,
It is sent to the buffer portion via 57, further processed in the main unit, and then stored again in the original jig 27 via the transport passages 48, 47 and 37.

The wafer 11 stored in the jig 28 is transferred to the transport passages 38, 37,
After being sent to the buffer portion via 47, 57, further processed in the main unit, they are again stored in the original jig 28 via the transport passages 48, 38.

The wafers 11 stored in the jig 29 are transported by the transport passages 39, 49,
It is sent to the buffer portion via 59 and 57, further processed in the main unit, and then stored again in the original jig 29 via the transport passages 48, 49 and 39.

In this example, the transport passages 37, 39 and 47, 49 act as connecting passages, and the transport passages 57, 59 act as bypass passages, but there is a risk of wafer collision due to intersections or overlaps of the transport passages. The reason is that while the wafers that have departed from the jig 27 and finished being transferred are stored in the original jig 27,
This is the case when the wafer 11 comes out from 28, and at this time, the jig
The transportation path of the wafer 11 supplied from 28 may be changed so as to pass through the transportation paths 38, 39, 49, 59 and 57.

[Effects of the Invention] Since the wafer transfer apparatus according to the present invention supplies and stores wafers from the same jig, it is possible to perform lot management for each jig of the wafer and to automate transfer within and between steps. Accordingly, it is possible to reduce the number of times the jigs are transported, and the management of the wafers by the computer is omitted, the lots of the wafers are not mixed, and the troubles of transportation can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a wafer transfer device according to an embodiment of the present invention, FIG. 2 is a plan view showing a state of the transfer device of the above embodiment, and FIG. FIGS. 4 and 5 are views for explaining another embodiment of the present invention, FIGS. 4 and 5 are views for explaining still another embodiment of the present invention, and FIGS. 6 to 9 are conventional wafers. It is a figure explaining the example of a conveyance apparatus. 11 …… Unprocessed wafer, 100 …… Station part, 200…
… Main device, 300 …… Buffer part, 21 ～ 29 …… Jig, 31
~ 59, 61 ~ 64, 81 ~ 84 …… Transport path, 71 ～ 74 …… Stocker jig, 60 …… Transport forward path, 90 …… Transport back path.

Claims (1)

[Claims] 1. A plurality of jigs installed in a station part for accommodating a large number of wafers, and a main processing unit for performing a predetermined process on unprocessed wafers respectively supplied from the plurality of jigs. A transport passage provided in the station part corresponding to each of the plurality of jigs, a connection passage connecting the transport passages in a grid pattern, one of the transport passages, and one of the processing main device. A transport outward path connecting with an inlet of an unprocessed wafer, a transport return path connecting another one of the transport paths with a processed wafer outlet of the processing main apparatus, and a three-dimensional intersection with the transport return path. And a bypass passage connecting one of the transport passages not connected to the transport forward path and the transport forward path, and a plurality of jigs for the transport passage network. Of the unprocessed wafers stored in one of the above-mentioned processing main devices, and a transfer route for guiding the processed wafers from the processing main device to the jig in which the wafers were stored. And a transfer path selecting means for selecting each of them by different paths.