JPH0871965A - Transfer device - Google Patents

Abstract

PURPOSE: To provide a high through-put transfer device with which an optimum transfer system can be selected and which can be widely used. CONSTITUTION: A transfer device is composed of a pair of transfer robots 1, 2 which cause a second crank mechanism to perform a crank motion in association with a first parallel crank mechanism in order to transfer a load carried by transfer links 13, 23. The transfer robots 1, 2 have a rotatable base plate 3 as a first link so that proximal ends of first link arms 12, 22 are line- symmetrically arranged about the rotational center P of the base plate 3. Further, the moving paths R of the transfer links 13, 23 set on one and the same line passing through the rotational center P of the base plate P in a condition such that they are vertically deviated from each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer device suitable for use in a multi-chamber system or the like in semiconductor manufacturing.

[0002]

2. Description of the Related Art FIG. 10 is a diagram for explaining a structural example of a transfer device of this type. In the figure, 51 is a servo motor, and the drive shaft of the servo motor 51 is connected to a driving force transmission portion 53 via a speed reducer 52. One end of each of a pair of link arms 54 is connected to the driving force transmission portion 53, and a work holder 55 is attached to the other end of the link arms 54.

In the transfer device having the above structure, the driving force of the servo motor 51 is transmitted to the pair of link arms 54 via the driving force transmission portion 53, whereby the link arm 5 is moved.
4 is expanded and contracted so that the transferred object (not shown) carried by the work holder 55 can be transferred to a predetermined place.

[0004]

However, in the above-mentioned transfer apparatus, the driving force transmitting portion 53 for transmitting the driving force of the servo motor 51 needs a gear mechanism, and the connecting portion between the link arm 54 and the work holder 55 is further required. Also in 56, a gear mechanism is required as a synchronizing mechanism for holding the orientation of the work holder 55 in one direction when the link arm 54 is expanded and contracted. Therefore, when using in a clean environment such as in a clean room or vacuum,
The gear mechanism described above has a disadvantage that it becomes a source of dust and reduces cleanliness. Further, in the case of a gear mechanism, the work holder 5 is affected by backlash, wear, etc.
There are also inconveniences such as vibration occurring in 5 and rattling in the expansion and contraction operation of the link arm 54.

Therefore, the present applicant proposes a new transfer device in Japanese Patent Application No. 6-17941 in order to eliminate the above-mentioned inconvenience. This transfer device is a combination of two parallel crank mechanisms. One parallel crank mechanism is interlocked with the other parallel crank mechanism to make a crank motion, and a transfer arm provided on the other parallel crank mechanism is used to cover the parallel crank mechanism. The transfer is carried while carrying the transferred material. In the case of this transfer device, pulleys, belts, etc. are used as components for driving force transmission, and since the gear mechanism that is a dust source is not used, the operation of the entire device is smooth and Suitable for use in a clean environment such as a clean room.

By the way, in a multi-chamber system or the like in semiconductor manufacturing, the semiconductor manufacturing apparatus is concerned with how quickly a work is transferred between a plurality of process chambers (processing chambers) and a load lock chamber (vacuum preliminary chamber). This is an important point in improving the overall throughput. Therefore, in particular, with regard to the transfer device used in this type of semiconductor manufacturing apparatus, it is possible to select a transfer system that is suitable for various system configurations without waste, and has a high versatility of a high-throughput transfer device. Suggestions are strongly desired.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is a first structure in which a pair of first link arms are bridged between a first link and a second link.
Parallel crank mechanism, and a second parallel crank mechanism formed by bridging a pair of second link arms between the second link and the transfer link. This is a transfer device composed of a pair of transfer robots for transferring an object to be transferred carried by a transfer link by cranking two parallel crank mechanisms. In the pair of transfer robots, a rotatable base plate is used as a common first link, and each base end portion of the first link arms is arranged line-symmetrically with respect to a rotation center of the base plate. The movement path of the work link is set on the same line passing through the center of rotation of the base plate in a state of being vertically displaced.

[0008]

In the transfer device of the present invention, the pair of transfer robots are cranked by independent drive sources so that the transfer arms do not collide with each other on the same line passing through the center of rotation of the base plate. Move in both directions with the top and bottom offset. Therefore, two transfer objects can be transferred at the same time by the transfer links of each transfer robot, and when holder parts are provided at both ends of each transfer link, four transfer objects are simultaneously transferred. Since the load can be transferred and bidirectional, the rotation angle of the base plate when changing the direction can be smaller.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a perspective view illustrating an embodiment of the transfer device according to the present invention. The transfer device shown in FIG. 1 is mainly composed of a pair of transfer robots 1 and 2 each having an independent drive source (described later). The pair of transfer robots 1 and 2 are configured with a base plate 3 which is rotationally driven by a drive motor (not shown) as a common first link. Hereinafter, one transfer robot 1 will be referred to as a "first transfer robot", and the other transfer robot 2 will be referred to as a "second transfer robot".

FIG. 2 is a diagram for explaining the structure of the first transfer robot 1. First, in FIG. 2A, a pair of first link arms 12 are provided so as to bridge between a base plate 3 that serves as a first link and an individual plate 11 that serves as a second link. 3, the individual plate 11 and the pair of first link arms 12 constitute a first parallel crank mechanism.

On the other hand, the individual plate 11 to be the second link
A pair of second link arms 14 are provided so as to bridge between the transfer link 13 and the transfer link 13. The individual plate 11, the transfer link 13, and the pair of second link arms 14 serve as a second link arm. Parallel crank mechanism is constructed. Holder parts 15 are provided at both ends of the transfer link 13, respectively.
Is provided, and a transfer target (not shown) is carried by the holder portion 15 at the time of transfer.

Further, the crank motion of the first parallel crank mechanism is transmitted to the second parallel crank mechanism at the connecting portion between the first parallel crank mechanism and the second parallel crank mechanism configured as described above. A transmission mechanism is provided.
That is, as shown in FIG. 2B, one of the pair of first link arms 12 is, for example, the first link arm on the left side in the figure.
A first pulley 16 is fixed to a tip end portion of the link arm 12, and the first pulley 16 is rotatably supported by an individual plate 11 which is a second link, for example, via a bearing (for vacuum) 17. ing. Also, the pair of second
A second pulley 18 having the same diameter as that of the first pulley 16 is fixed to either one of the link arms 14, for example, the base end portion of the second link arm 14 on the left side in the drawing. Similar to the first pulley 16, it is rotatably supported by the individual plate 11 that is the second link via a bearing (for vacuum) 17. Further, the first pulley 16
A pair of belt members (for example, stainless belts) 19 are stretched between the first pulley 16 and the second pulley 18 in a state of intersecting with each other (cross belt system), and when the first pulley 16 rotates in one direction, The second pulley 18 is adapted to rotate in the opposite direction.

On the other hand, the other end (right side in the drawing) of the first link arm 12 and the base end of the second link arm 14 are rotatably attached to the individual plate 11 via bearings 17, respectively. It is supported. In addition, at the base end portion of the first link arm 12 (for example, the left side in the drawing), the first
As a drive source for cranking the parallel crank mechanism, a drive motor M is connected via a base plate 3 as shown in the figure.

Next, the operation of the first transfer robot 1 will be described. First, in the initial state, the first link arm 12 of the first parallel crank mechanism and the second link arm 14 of the second parallel crank mechanism are in parallel with each other. When the drive motor M is operated from this state, the first link arm 12 connected thereto swings in the direction of A1 in the figure with the base end portion as a fulcrum, and in cooperation with this, the first parallel crank mechanism. Cranks. Then, the first pulley 16 rotates in the R1 direction with respect to the individual plate 11 as much as the first link arm 12 swings,
In conjunction with this, the second pulley 18 rotates in the R2 direction with respect to the individual plate 11.

As a result, the second link arm 14 rotates around the base end of the second link arm 14 as the fulcrum, and along with the rotation of the second pulley 18, A2 in the figure.
The second parallel crank mechanism cranks in cooperation with this. As a result, the transfer link 13 moves in the X1 direction in the figure by an amount corresponding to the crank movements of the first parallel crank mechanism and the second parallel crank mechanism.
The transfer target (not shown) carried by the holder portion 13 is transferred to a predetermined place. Further, after the transferred object (not shown) is transferred, the drive motor M is rotated in the reverse direction by the same amount of rotation as before, so that the first parallel crank mechanism and the second parallel crank mechanism respectively move in opposite directions. Crank motion to return to the initial state. On the other hand, the transfer arm 13 is set to X2.
When moving in the direction, only the rotation direction of the drive motor M is reversed by the same procedure as above.

As shown in FIG. 1, the second transfer robot 2 is mainly composed of an individual plate 21, a first link arm 22, a transfer link 23 and a second link arm. These main parts are the individual plate 11 and the first link arm 1 that make up the first transfer robot 1.
2. Since these are the same parts as the transfer link 13 and the second link arm 14, the description of the configuration and operation of the second transfer robot 2 is omitted in this embodiment.

Next, an arrangement form of the first transfer robot 1 and the second transfer robot 2 having the above-mentioned configuration will be described. First, on the base plate 3 which is the common first link, as shown in FIG. 3, the first link arm 12 on the first transfer robot 1 side and the first link arm 22 on the second transfer robot 2 side are connected. Each of the base end portions 12a and 22a is
They are arranged line-symmetrically with respect to the rotation center P of the base plate 3.

Further, the transfer link 13 on the side of the first transfer robot 1 and the transfer link 23 on the side of the second transfer robot 2 avoid the positional interference with each other. As shown, the transfer link 23 on the second transfer robot 2 side is arranged above the transfer link 13 on the first transfer robot 1 side with a predetermined gap. By the way, the gap between the transfer links 13 and 23 is set so that positional interference does not occur even when the transfer links 13 and 23 carry the transferred objects. Further, as shown in FIG. 1, the moving paths R of both transfer links 13 and 23 are both set on the same line passing through the rotation center P of the base plate 3, and as described above, Since the links 13 and 23 are arranged so as to be vertically displaced from each other, the moving paths R of the respective transfer links 13 and 23 are also set to be vertically displaced.

Therefore, when the first transfer robot 1 and the second transfer robot 2 are actually cranked by independent drive sources (drive motors M), they follow the rotation directions of the respective drive motors M. , The transfer arms 13 and 23 move bidirectionally in a vertically shifted state so as not to collide with each other on the same line passing through the rotation center P of the base plate 3.

Next, the operation mode of the transfer apparatus of this embodiment will be described with reference to FIGS. Note that FIG.
9A and 9B, in order to make the operating states of the first transfer robot 1 and the second transfer robot 2 easy to understand, the transfer links are drawn laterally offset, but in actuality, any The transfer link also moves along the movement route set on the same line.

First, as an example, an operation procedure when used in a semiconductor manufacturing apparatus having one process chamber will be described with reference to FIGS. In the illustrated semiconductor manufacturing apparatus, 31 is a cassette chamber, 32 is a load lock chamber (front chamber), 33 is a transfer chamber, and 34 is a process chamber.
The first transfer robot 1 and the second transfer robot 2 which are links are installed in the transfer chamber 33. The number of workpieces (transferred objects) 35 before processing is, for example, 1
The lots are stored in a work cassette (not shown), and are supplied from the cassette chamber 31 to the load lock chamber 32 in this state.

At the start of transfer, as shown in FIG. 5A, the first transfer robot 1 cranks from the state in which the transfer robots 1 and 2 face the load lock chamber 32, and the load lock chamber 32 is moved. Work 3 before entering the process
Take out 5. Next, as shown in FIG. 5B, the transfer robots 1 and 2 face the process chamber 34 side due to the rotation of the base plate 3, and the first transfer robot 1 cranks from that state to move inside the process chamber 34. To supply the unprocessed work 35 thereto.

Next, as shown in FIG. 5C, the transfer robots 1 and 2 face the load lock chamber 32 side by the rotation of the base plate 3, and the first transfer robot 1 is moved from that state.
Moves into the load lock chamber 32 by cranking and takes out the unprocessed work 35 from there. Then, in FIG.
As shown in (a), the transfer robots 1 and 2 face the process chamber 34 side by the rotation of the base plate 3, and the second transfer robot 2 cranks from that state and advances into the process chamber 34. The processed work piece 35a is taken out from.

Further, from that state, as shown in FIG. 6 (b), the first transfer robot 1 cranks to advance into the process chamber 34, and the work 35 before processing is supplied thereto. After that, the transfer robots 1 and 2 face the load lock chamber 32 side by the rotation of the base plate 3, and the second transfer robot 2 makes a crank motion from that state and advances into the load lock chamber 32, and the processed robots are processed there. The work 35a is supplied.

Thereafter, the series of operations shown in FIGS. 5C to 6C are repeated according to the number of works 35 for one lot. Then, after the work 35 before processing is lost in the load lock chamber 32 and the processed work 35a is returned to the load lock chamber 32, the transfer robots 1, 2 are transferred until the processing of the work 35 in the process chamber 34 is completed. Stands by while facing the process chamber 34 side. Then, when the processing in the process chamber 34 is completed, the second transfer robot 2 takes out the processed work 35a from the process chamber 34, returns it to the load lock chamber 32, and processes one lot of the work 35a. Is completed.

Next, an operation procedure when used in a semiconductor manufacturing apparatus having two process chambers will be described with reference to FIGS. In the illustrated semiconductor manufacturing apparatus, 31 is a cassette chamber, 32 is a load lock chamber (front chamber), 33 is a transfer chamber, and 34a and 34b.
Is the process chamber. In this embodiment, the two process chambers 34a and 34b perform the same processing on the work. In addition, one of the process chambers 34a is referred to as a "first process chamber".
And the other process chamber 34b is referred to as a "second process chamber".

At the start of transfer, as shown in FIG. 7 (a), both transfer robots 1 and 2 are cranked from the state in which the transfer robots 1 and 2 face the load lock chamber 32 side to perform load lock. It advances into the chamber 32 and takes out one unprocessed work 35 each. Next, FIG.
As shown in (b), the transfer robots 1 and 2 face the first process chamber 34a side by the rotation of the base plate 3, and the first transfer robot 1 cranks from that state to move into the first process chamber 34a. It advances and supplies the unprocessed work 35 to it.

Next, as shown in FIG. 7C, the transfer robots 1 and 2 face the second process chamber 34b side by the rotation of the base plate 3, and the second transfer robot 2 cranks from that state. Second process chamber 3
4b, and the work 35 before processing is supplied there. Subsequently, as shown in FIG. 8A, the transfer robots 1 and 2 are moved by the rotation of the base plate 3 to cause the load lock chamber 3 to move.
2 side, the first transfer robot 1 cranks from that state and advances into the load lock chamber 32, and the work 35 before processing is taken out therefrom, and further, as shown in FIG. 3 is reversed (rotated by 180 degrees), the first transfer robot 1 advances into the load lock chamber 32 again, and the work 35 before processing is taken out therefrom. As a result, the works 35 are carried on both ends (holders 15) of the transfer link 13 (FIGS. 1 and 2) of the first transfer robot 1 one by one.

Next, as shown in FIG. 8C, the transfer robots 1 and 2 face the first process chamber 34a by the rotation of the base plate 3, and the second transfer robot 2 cranks from that state. First process chamber 34a
It advances into the inside and takes out the processed work 35a from there. Further, subsequently, as shown in FIG. 9A, the first transfer robot 1 cranks to advance into the first process chamber 34a, and supplies the unprocessed work 35 thereto.

Then, as shown in FIG. 9B, the transfer robots 1 and 2 face the second process chamber 34b by the rotation of the base plate 3, and the second transfer robot 2 cranks from that state. Second process chamber 34
It advances into the inside of b and takes out the processed work 35a from there. As a result, the transfer link 2 of the second transfer robot 2
The works 35 are carried one by one on both ends (holder 25) of 3 (FIG. 1). Further, from that state, as shown in FIG. 9C, the first transfer robot 1 cranks and advances into the second process chamber 34b, and supplies the unprocessed work 35 thereto.

Thereafter, the first transfer robot 1 and the second transfer robot 2 sequentially advance into the load lock chamber 32 without the base plate 3 rotating, and the work 35 before processing and the processed work 35a are taken out. After the supply of
The first transfer robot 1 and the second transfer robot 2 sequentially advance into the load lock chamber 32 from the state where the base plate 3 is inverted (rotated by 180 degrees), and the work 35 before processing is taken out and processed in the same manner as above. The finished work 35a is supplied. As a result, similarly to FIG. 8B, the works 35 are carried one by one on both ends (holders 15) of the transfer link 13 (FIGS. 1 and 2) of the first transfer robot 1. After that, the work 3 that has been processed in the load lock chamber 32 will be used thereafter.
The series of operations shown in FIG. 8C to FIG. 9C are repeated until all 5a are returned.

[0032]

As described above, according to the transfer apparatus of the present invention, the pair of transfer robots are cranked by independent drive sources so that the transfer robots can be moved on the same line passing through the center of rotation of the base plate. Since the transfer arm can be moved in both directions, it is possible to transfer two transfer objects at the same time by using the transfer links of each transfer robot, and further When the holder portions are provided at both ends, it is possible to transfer four transfer objects at the same time. Further, since all the transfer robots are bidirectional, the rotation angle of the base plate at the time of changing the direction can be smaller than the conventional one. Therefore, especially for a semiconductor manufacturing apparatus that employs a multi-chamber system, it is possible to transfer workpieces more quickly and efficiently between a plurality of chambers, thus improving the throughput of the entire semiconductor manufacturing apparatus. As a matter of course, it is possible to provide a transfer device excellent in versatility capable of selecting an optimum transfer method corresponding to various system configurations.

[Brief description of drawings]

FIG. 1 is a perspective view illustrating an embodiment of a transfer device according to the present invention.

FIG. 2 is a diagram illustrating a configuration of a transfer robot.

FIG. 3 is a plan view of a main part for explaining an arrangement form of a transfer robot.

FIG. 4 is a side view of a main part for explaining an arrangement form of a transfer robot.

FIG. 5 is a diagram (No. 1) for explaining the operation mode of the transfer device.

FIG. 6 is a diagram (No. 2) for explaining the operation mode of the transfer device.

FIG. 7 is a diagram (No. 1) explaining another operation mode of the transfer device.

FIG. 8 is a diagram (No. 2) explaining another operation mode of the transfer device.

FIG. 9 is a diagram (No. 3) explaining another operation mode of the transfer device.

FIG. 10 is a diagram illustrating a conventional example.

[Explanation of symbols]

 1 1st transfer robot 2 2nd transfer robot 3 Base plate (1st link) 11, 21 Piece plate (2nd link) 12, 22 1st link arm 13, 23 Transfer link 14, 24 2nd link arm

Claims (2)

[Claims] 1. A first parallel crank mechanism formed by bridging a pair of first link arms between a first link and a second link, and a pair of a first parallel crank mechanism between the second link and a transfer link. A second parallel crank mechanism formed by bridging a second link arm, and by interlocking with the first parallel crank mechanism to crank the second parallel crank mechanism, the transfer link is provided. A transfer device comprising a pair of transfer robots for transferring an object to be transferred and carried, wherein the pair of transfer robots has a rotatable base plate as a common first link. The base ends of the arms are arranged line-symmetrically with respect to the rotation center of the base plate, and the transfer paths of the transfer links pass through the rotation center of the base plate in a vertically displaced state. Transfer device, characterized in that it is set on the line. 2. The transfer device according to claim 1, wherein holders for supporting the transferred object are provided at both ends of the transfer link.