JPH07147310A - Method and apparatus for transportation - Google Patents

Abstract

PURPOSE:To eliminate the need for a transfer robot between process devices and a tunnel device as a transfer channel by using a system in which a lift and a carriage cooperate to function as a robot to transfer a wafer from the former to the latter. CONSTITUTION:A buffer chamber 8 is provided between process devices 3 and a tunnel 11 isolated from the outdoor air for passing a carriage 1 that carries wafers 2. The buffer chamber comprises means for allowing the carriage to enter, stop and go back; a shaft 12 that is rotatable and vertically movable; and a plate 9 that protrudes from the shaft to support wafers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to transfer of wafers and the like suitable for manufacturing semiconductors and the like, and in particular, it is equipped with a carrier truck for carrying an object (wafer or the like) to be transferred inside a tunnel, and using a tunnel partition wall to open the outside air. The present invention relates to a transfer device and method for transferring an object to be transferred to a semiconductor processing apparatus or the like from a tunnel transfer device that transfers the object to be transferred in a vacuum state or the like in which the above is blocked.

2. Description of the Related Art FIG. 7 shows an example of the arrangement of a processing chamber in which a semiconductor manufacturing apparatus is arranged. In this processing chamber, process processing under vacuum, namely sputtering, ion implantation,
Alternatively, processing such as dry etching is performed. In this processing chamber, a vacuum storage 10 for storing semiconductor substrates under vacuum is provided.
And a tunnel transfer device 11 for transferring a wafer in a tunnel maintained in a vacuum state that connects the vacuum storage 10 and the process device 3. Also, the wet cleaning device 5
The wafer transfer device 6 and the wafer transfer device 6 are provided so that the wafer after cleaning is vacuum-stored and further transferred to each process device 3 while being magnetically levitated in the vacuum tunnel.

FIG. 8 is a sectional view of a transfer device (here, a magnetic levitation transfer device is used) 11 for transferring a wafer in a vacuum tunnel. Regarding the magnetic levitation transport device having such a structure, the applicant of the present invention has applied for an international patent application PCT / JP.
The details are disclosed in 93/09930 and the like. Above the tunnel partition 30, levitation electromagnets 31 are lined up along the tunnel. Similarly, linear motors 32 for traveling are arranged in a row along the tunnel below the tunnel partition 30. The carrier 1 on which the semiconductor substrate 33 is mounted is
A magnetic material 34 is provided on the upper surface, and the carrier 1 is suspended by the magnetic attraction force of the levitation electromagnet 31. The carrier table 1 is horizontally driven by a linear motor 32 in a suspended state. With such a configuration of the transfer device 11, the wafer 2 is mounted on the transfer table 1, and the partition 30 of the vacuum tunnel is installed.
The vacuum storage 10 and the processing device 3 in a non-contact floating state from the
Transported between.

FIG. 9 shows details of the structure of the vacuum storage 10. FIG. 9 (A) is a plan view of the vacuum storage 10, and FIG. 9 (B) shows its sectional structure. The vacuum storage chamber 25 has a tunnel shape similar to that of the magnetic levitation transfer device. Inside the vacuum storage chamber, a storage shelf (storage cart) 24 on which the wafer 2 is placed is contactless by a levitation electromagnet 31. It can be floated and held at the same time, and can be moved / stopped without contact by a linear motor. That is, the storage rack 24 is linearly movable in the tunnel-shaped vacuum storage chamber 25. The wafer 2 is transferred from the load lock chamber 6 to the storage shelf 24 of the vacuum storage chamber 25 by the robot 26 of the robot chamber 23. As described above, in the storage case 10, the wafers 2 can be stored in a large number of stages in three rows by moving the storage shelves (carts) 24. Further, since the storage rack 24 is moved in vacuum in a non-contact manner by magnetic levitation, the wafer 2 is prevented from being contaminated with molecules and particles.

In the vacuum tunnel transfer device, in order to match the takt time of the connected vacuum processing device,
It is necessary to carry multiple wafers at once. On the other hand, since the vacuum processing itself is processed by a single wafer, the wafer transfer device (robot) mounted inside the processing apparatus is also generally of a type that carries single wafers, that is, wafers one by one. In addition, the range of vertical movement of this robot is generally 10 to 200 because of the height required for picking up a wafer and the cost.
Some are about mm, or some do not move up and down at all.

Therefore, in order to connect the vacuum processing apparatus for transferring wafers in a single wafer and the vacuum tunnel transfer apparatus for transferring a plurality of wafers at a time, transfer between the two is performed for wafer transfer. Equipment is required. FIG. 10 shows an example of a semiconductor manufacturing apparatus including a conventional transfer apparatus, and FIG.
Shown in. As shown in FIG. 10, the vacuum tunnel transfer device 1
1 is connected to the robot chamber 23 by a connection chamber 28.
The carrier 1 carrying the wafer 2 opens the gate valve 18, enters the connection chamber 28, and stops.

In FIG. 11, the carriage 1 is stopped at a predetermined position in the connection chamber 28. A plurality of wafers 2 are vertically placed on a shelf installed inside the carrier 1 in a horizontal state. The transfer device includes a vacuum robot 27 and a vacuum elevator 28. The vacuum robot 27 may be a single-wafer type in which wafers are transferred one by one, or may be a type in which a plurality of wafers are transferred simultaneously. The latter has the advantage that the transfer time is shortened and the range of vertical movement is shortened, but on the other hand, the increase in the weight of the arm tip causes a large amount of deflection of the arm tip when the arm is extended. . Whichever robot is used, this robot is equipped with wafers 2 lined up and down on the carrier.
The area that must be moved up and down in order to transfer is much larger than a normal robot. On the other hand, the elevator 28 has a shelf plate like the carrier 1 and has a function of temporarily storing the wafer 2 transferred from the carrier 1. After all the wafers 2 have been transferred to the elevator 28, the transfer robot 26 on the side of the process device 3 extracts the wafers 2 one by one from the shelf plate of the elevator 28,
Transfer to the process processor 3. Elevator 28 at this time
Is moved up and down to adjust the position of the wafer in the height direction according to the range in which the transfer robot 26 on the process apparatus side can move up and down.

[0007]

However, this conventional wafer transfer device has the following problems. Since the robot 27 and the elevator 28 must be installed for each process device 3, there is a cost. In particular, since the robot used here has a wide range of vertical movement, it is necessary to use a bellows having a large diameter and a large expansion / contraction range, so that the cost is almost double that of an ordinary robot. Originally, where the wafer should be directly transferred from the vacuum tunnel transfer device 11 to the vacuum processing device 3, the transfer process described above is added, so that the transfer time is extra. This is related to the tact time of the semiconductor process. Since a clean room has a high construction cost per unit area, it is required that the floor space occupied by the equipment in the clean room is as small as possible. However, this apparatus requires an additional floor area because the robot chamber needs to be installed between the process apparatus and the tunnel transfer apparatus.

According to the present invention, in order to solve the above problems, the function of the conventional transfer robot 27 is separately provided in the elevator 28 and the connection chamber 28 of the carrier, and the wafers are cooperatively worked by both. By transferring from the carrier truck to the elevator, the transfer robot 27 between the process device and the tunnel carrier device is unnecessary.

[0009]

A transfer device according to the present invention is a buffer between a processing device and a tunnel transfer device for separating an external air from the processing device and mounting and transferring an object to be transferred on a transfer carriage. A chamber is provided, and the buffer chamber has means for advancing, stopping, and retreating the carriage, a support shaft that is vertically movable and rotatable, and a support plate that projects from the support shaft and mounts the transported object. It is characterized by having.

[0010]

A wafer support plate, which can move up and down and can rotate with respect to a support shaft, is installed in the vicinity of the stop point advancing direction of the transfer carriage inside the buffer chamber of the vacuum tunnel. The support plate has such a shape and positional relationship that the plate can be inserted under the wafer mounted on the carrier when the carrier is stopped at a predetermined position. After the carrier is stopped in place, the support plate is raised as necessary to lift the wafer from the shelf of the carrier. After that, the carrier truck moves backward. In this state, all the wafers are transferred from the carrier to the support plate at one time. However, in this state, the support shaft of the support plate interferes with the transfer robot in the process chamber, and it is impossible to take the wafer. Therefore, by rotating the support plate by 180 degrees by the support shaft and moving the wafer in front of the process apparatus, the transfer robot in the process chamber can take the wafer from the support plate.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in FIGS.

FIG. 1 shows the arrangement of the entire semiconductor manufacturing apparatus according to an embodiment of the present invention. It can be seen that unlike the conventional arrangement example of FIG. 10, the buffer chamber 8 directly connects the robot chamber 23 of the vacuum process device 3 and the tunnel transfer device 11 without the transfer robot chamber and the elevator chamber. Therefore, the area occupied by the whole is significantly smaller than the conventional one.

FIG. 2 shows a detailed sectional structure of the buffer chamber 8. A support shaft 12 on which a support plate 9 projects is installed immediately in front of the stop position of the carrier. The support shaft 12 is isolated from the outside air (atmosphere) by a bellows magnetic fluid seal 13, and one end of the support shaft 12 penetrates the magnetic fluid seal 13 and is connected to a motor 14 on the atmosphere side so as to be rotatable. The motor 14 is preferably a stepping motor. The support shaft 12 of this support plate is supported by a bearing 15 on the outside air side. These bearings 1
The motor 5 and the motor 14 are supported by a vertical movement mechanism 16, and the support plate 9 is movable vertically. A plurality of the support plates 9 are installed at the same pitch as the shelves of the carrier, corresponding to the number of wafers mounted on the carrier. The plate 9 has such a shape positional relationship that it enters under the wafer 2 as shown in FIG. 3 (B) when the carrier 1 stops at a predetermined position. Further, this support plate 9 has a convex portion 17 capable of rotating 180 degrees about its support shaft 12, and the partition wall 30 of the tunnel as shown in FIG. 3 (A). .

Next, the transfer method will be described with reference to FIGS. 4 to 6. First, as shown in FIG. 4, the transfer carriage that travels along the tunnel transfer path and carries a wafer stops immediately before the gate valve 18 of the buffer chamber 8, opens the gate valve 18 and enters the buffer chamber 8 portion, and Stop at the position (step). The support plate 9 of the buffer chamber 8 is set to a height such that the plate can enter under the wafer 2 mounted on the shelf of the carrier 1.

In FIG. 5, after the carriage is stopped, the support plate 9 is raised by the amount necessary to lift the wafer from the shelf of the carriage (step). After that, the carrier vehicle 1 is retracted to the tunnel carrier device 11 (step). In this state, the wafer 2 is transferred from the carrier to the support plate 9.

Next, as shown in FIG. 6, the gate valve 18 is closed (step), the support plate 9 is rotated 180 degrees by the support shaft 12, and the wafer 2 is moved in front of the robot chamber 23 of the process apparatus 3. (Step). After that, the wafer 2 is transferred to the process device 3 by the single wafer type wafer transfer robot 26 on the process device 3 side.

The processed wafers can be transferred from the process device 3 to the shelf of the transfer table 1 and transferred to another process device or a storage by the procedure which is completely opposite to the above procedure. it can.

In the above embodiment, it is preferable to use the magnetic levitation transfer device shown in FIG. 8 as the tunnel transfer device 11 in order to secure cleanliness. However, as the tunnel transfer device, a contact type device in which a wafer is transferred by a transfer carriage having ordinary wheels may be used. or,
Although the wafer transfer destination is the process device, it may be a storage room such as a vacuum storage.

Further, the buffer chamber 8 is provided with a levitation electromagnet 31, a linear motor 32, a stop positioning device 35, and a magnetic material 34 and a conductive material 36 on the outer side of the tunnel partition wall, similarly to the magnetic levitation transfer device shown in FIG. It is preferable that traveling and stop positioning can be performed while magnetically levitating the carrier 1. However, in the case of using the contact type as the tunnel transfer device, it is necessary to provide the entrance, stop, and retreat means of the transfer vehicle similar to the tunnel transfer device.

The inside of the tunnel transfer path 11 and the buffer chamber 8 is preferably a vacuum atmosphere that is shielded from the outside air (atmosphere) from the viewpoint of preventing molecular contamination and particle contamination of the wafer. However, depending on the type of semiconductor process, it may be preferable to use a clean gas atmosphere such as N ₂ gas, or it may be preferable to use a clean air atmosphere.

Further, although the semiconductor wafer has been described as an example of the object to be transferred in the present embodiment, it is needless to say that it can be widely applied to the liquid crystal substrate or the object to be processed which needs to be processed in a clean atmosphere. As described above, various modified embodiments are possible without departing from the spirit of the present invention. In the drawings, the same reference numerals indicate the same or corresponding parts.

[0022]

According to the present invention, the supporting plate 9 for the transported object, which can be moved up and down and is further rotatable, is installed in the vicinity of the traveling direction of the stop point of the carrier truck inside the buffer chamber of the vacuum tunnel. The transfer robot between the process equipment and the tunnel carrier could be omitted. Therefore, the transfer of the wafer from the tunnel transfer device to the support plate 9 (elevator) does not have to be performed by the transfer robot and only once, which reduces the manufacturing cost of the device and significantly reduces the installation area.

[Brief description of drawings]

1 to 6 are diagrams for explaining an embodiment according to the present invention, and FIG. 1 is an explanatory diagram showing a connection configuration between a process device and a tunnel transfer device according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing the structure of a buffer chamber.

3 (A) is a plan view and FIG. 3 (B) is a side sectional view showing a main part of FIG.

FIG. 4 is a sectional view showing a wafer transfer step in the buffer chamber.

FIG. 5 is a sectional view showing a wafer transfer step in the buffer chamber.

FIG. 6 is a sectional view showing a wafer transfer step in the buffer chamber.

FIG. 7 is an explanatory diagram showing an example of a layout configuration of a conventional semiconductor manufacturing apparatus.

FIG. 8 is a sectional view of a magnetic levitation transport device.

FIG. 9 is a plan view (A) and a side sectional view (B) of a vacuum storage.

FIG. 10 is an explanatory diagram showing an example of a connection between a conventional process device and a tunnel transfer device.

11 is a cross-sectional view of the main parts of FIG.

[Explanation of symbols]

 1 Transfer Platform (Car) 2 Wafer 3 Vacuum Process Device 8 Buffer Chamber 9 Support Plate 11 Vacuum Tunnel Transfer Device 12 Support Axis 23 Robot Room

Front page continued (72) Inventor Takeshi Yoshioka 4-2-1 Motofujisawa, Fujisawa City, Kanagawa Prefecture EBARA Research Institute

Claims (5)

[Claims] 1. A buffer chamber is provided between a processing apparatus and a tunnel transfer apparatus which is mounted on a transfer carriage and transfers an object to be transferred, the buffer chamber being isolated from the processing apparatus and the transfer chamber being the transfer chamber. A transfer device comprising: means for moving the carriage in, stopping, and retreating; a support shaft that is vertically movable and rotatable; and a support plate that projects from the support shaft and mounts the transported object. 2. A buffer chamber is provided between the processing device and a tunnel transfer device for mounting and transferring an object to be transferred in the processing device while being isolated from the outside air, and the transfer vehicle is provided with the buffer chamber. A step of entering and stopping the chamber, a step of receiving an object to be transferred from the transfer carriage by vertically moving a support plate protruding from a support shaft and mounting the object to be transferred, and the transfer carriage from the buffer chamber. It comprises a step of retreating, a step of rotating the support shaft to move an object to be transferred placed on the support plate in front of the processing apparatus, and a robot of the processing apparatus receiving the object to be transferred. A method for transferring an object to be conveyed, which is characterized in that: 3. The buffer chamber is provided with a levitation electromagnet, a traveling linear motor, and a stop positioning device outside the partition wall, and a transport carriage including a magnetic material and a conductive material enters and stops in a magnetically levitated state. The transfer device according to claim 1, wherein the transfer device is moved backward. 4. The magnetic levitation transfer device, wherein the tunnel transfer device includes a levitation electromagnet and a traveling linear motor outside a partition wall, and causes a trolley carrying a magnetic material and a conductive material to travel in a magnetically levitated state. 4. The method according to claim 3, wherein
The transfer device described. 5. The transfer device according to claim 1, wherein the buffer device and the tunnel transfer device have a vacuum inside the tunnel partition wall and are isolated from the outside atmosphere side.