JP2002313876A - Automatic guided vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the structure of a fixed type cassette for temporarily storing a wafer that is mounted on an automatic guided vehicle that automatically carries and transfers a semiconductor wafer between stations at a semiconductor-manufacturing factory or the like. SOLUTION: A turn support axis 51 is provided at a side close to the rear surface of a buffer cassette 5, the buffer cassette 5 is composed so that it can be inclined, and the buffer cassette 5 is fixed while wafers 10, 10, and the like in the buffer cassette 5 are horizontal, thus placing the wafers 10, 10, and the like to the buffer cassette 5 horizontally. Or, the buffer cassette 5 is inclined and is fixed to a state where the wafers 10, 10, and the like in the buffer cassette 5 are inclined to the depth side (rear surface side) of the buffer cassette 5, thus preventing the wafers 10, 10, and the like in the buffer cassette 5 from jumping out when the automatic guided vehicle 1 is driven.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic guided vehicle for automatically transporting and transferring semiconductor wafers between stations in a semiconductor manufacturing plant, and more particularly, to a fixed type for temporarily storing a wafer mounted on the automatic guided vehicle. It relates to the structure of a cassette.

[0002]

2. Description of the Related Art Conventionally, in a semiconductor manufacturing plant where the generation of dust is a problem, there has been a technology for automatically moving an unmanned transfer vehicle equipped with a scalar arm type robot arm in order to transfer and transfer semiconductor wafers. Are known. The unmanned transfer vehicle includes an unmanned transfer vehicle equipped with a wafer robot arm for transferring wafers one by one, and a cassette robot arm and a wafer robot arm for transferring a cassette containing many wafers. Automated guided vehicles have been developed. When transferring wafers from an automatic warehouse or the like to a processing device or an inspection device, in an automatic guided vehicle equipped with a robot arm for transferring wafers, the robot arm takes out wafers one by one from the automatic warehouse or the like and transfers the wafers unattended. The car was moved and the wafer was delivered to a predetermined inspection device or processing device. Further, in an unmanned carrier equipped with a robot arm for transferring a cassette and a robot arm for transferring a wafer, a cassette in which wafers are stored in advance is used.
Each cassette is received by a cassette transfer robot arm and mounted on an unmanned carrier, the unmanned carrier is moved, and wafers are taken out of the cassette by a wafer transfer robot arm and received by an inspection device or a processing device. I had to pass it.

[0003]

However, the former has a problem that the working efficiency is poor, and the latter requires a lock means or the like for preventing the cassette from rattling. In order to prevent the wafer from jumping out, it is necessary to take measures such as placing the wafer loading / unloading port of the cassette upward.

Meanwhile, a wafer is set in a horizontal state (horizontally) by a wafer transfer arm with respect to an inspection apparatus or a processing apparatus, and a cassette is mounted with a wafer loading / unloading port facing upward. Therefore, the wafer is taken out of the cassette in a vertical direction. For this reason, an up-down turning mechanism is required to turn the wafer holding portion at the tip of the transfer arm in the up-down direction and accurately change the position and orientation of the wafer from vertical to horizontal. Further, the transfer arm is provided with a horizontal turning mechanism for turning the wafer holding portion in a horizontal plane. If the vertical turning mechanism is provided in addition to the horizontal turning mechanism, the control becomes complicated. However, it was disadvantageous in terms of cost.

[0005]

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described. That is, in an automatic guided vehicle equipped with a transfer means for transferring a wafer and a fixed cassette for temporarily storing the wafer, when the transfer means transfers the wafer to the cassette. Sets a cassette so that wafers can be taken in and out in a horizontal state, while the cassette is set so as to prevent wafers from jumping out of the cassette when running an unmanned carrier.

In addition, the cassette is tilted on an automatic guided vehicle to prevent the wafer from jumping out of the cassette.

According to a third aspect of the present invention, a rotation fulcrum is provided on a side close to the rear surface of the cassette so that the cassette can be tilted, and the wafer inside the cassette is in a horizontal state or the wafer inside the cassette. The cassette is fixed in position with tilting toward the back (back side) of the cassette.

[0008]

Next, embodiments of the present invention will be described with reference to the drawings. 1 is a perspective view showing an automatic guided vehicle 1 in a clean room, FIG. 2 is a side sectional view of the automatic guided vehicle 1, FIG. 3 is a plan view of the same, and FIG. 4 (a) is a view of a wafer 10 having an orientation flat 10a. FIG. 4B is a plan view of the wafer 10 having the notch 10b, FIG. 5 is a side cross-sectional view of the automatic guided vehicle 1 when the base 38 is raised, and FIG. FIG. 6B is a plan view of the automatic guided vehicle 1 when the wafer 1 is transferred to the posture adjusting device 4, and FIG.
Automatic guided vehicle 1 when transferring 0 to buffer cassette 5
FIG. 6C is a plan view of the automatic guided vehicle 1 when the wafer 10 is taken out from the buffer cassette 5, and FIG.
8 is a block diagram illustrating a control configuration of the automatic guided vehicle 1, FIG. 8 is a block diagram illustrating a control configuration of the automatic guided vehicle system, and FIG. 9 is a flowchart illustrating a transfer process (first half) of the wafer 10 by the automatic guided vehicle 1. 10 is a flowchart showing the transfer process (second half) of the wafer 10 by the automatic guided vehicle 1.

First, the overall configuration of the automatic guided vehicle 1 will be described. In the following description, the front, rear, left, and right positions of each structure will be described with the direction of arrow F in FIG. Also,
The front, rear, left and right positions of each structure in the other drawings are also in accordance with FIG.

As shown in FIG. 1, the automatic guided vehicle 1 is a tracked truck that automatically travels on traveling rails 20 and 20,
The vehicle body 2 is supported by traveling wheels 9, 9/9, 9 and the traveling wheels 9/9/9 are connected to respective drive motors 8.
The vehicle is driven by 8.8 (FIG. 2) and runs on the running rails 20 by four-wheel drive. In the present embodiment, the drive is transmitted to all the running wheels 9, 9, 9, 9 in order to reduce the slip, and the driving motors 8, 9, 9, 9 are respectively provided to the running wheels 9, 9, 9, 9. Although 8.8.8 is attached, the mechanism for transmitting the drive to all the running wheels 9.9.9 is not limited to this, and another mechanism may be used. In addition, the number of drive wheels is not limited to four as long as they are provided at the front and rear of the vehicle, respectively.

.. And a stocker 22 are arranged along the traveling rails 20. A plurality of cassettes 23 are arranged on the stocker 22 at predetermined intervals. Has been established. Each cassette 23
.. Are arranged with their openings facing the running rails 20. On the front and rear inner surfaces of the cassette 23, a plurality of shelves for holding the side edges of the wafers 10 are provided in a vertical direction. The wafers 10, 10... In the present embodiment, the stocker 22 is a flat-type stocker for ease of explanation, but the cassette 23 is transferred between the carry-in / out port of the cassette 23, a number of shelves, and the shelf and the carry-in / out port. It may be an automatic warehouse equipped with a stacker crane.

As shown in FIGS. 2 and 3, a body 10 of the automatic guided vehicle 1 has a wafer 10 at the center thereof.
Are provided, and before and after the transfer device 3, the orientation adjusting device 4 for aligning the direction of the wafers 10, 10,... And the center position, and the wafers 10, 10,. A buffer cassette 5 is provided.

The wafer 10 has a substantially disk-like shape made of silicon single crystal, and the silicon crystal has an orientation. Therefore, as shown in FIG.
That is, one having an orientation flat (orientation flat) 10a formed on a part of the outer periphery of the wafer 10, or one having a notch 10b in which a part of the outer periphery of the wafer 10 is cut off as shown in FIG. In each case, an ID mark 11 that encodes wafer information such as a wafer manufacturing history is engraved on the peripheral portion on the front surface or the rear surface.

Next, the transfer device 3 will be described.
As shown in FIGS. 2 and 3, the transfer device 3 includes a transfer arm 30M / 30S, a base 38, and a turntable 39/39.
The base 38 is embedded in the center of the vehicle body 2, a turntable 39 is pivotally mounted on the base 38, and a pair of transfer arms 30M and 30S are mounted on the turntable 39.

As shown in FIG. 5, the base 38 is configured to be able to move up and down. A rod having threaded threads is erected on the side of the base 38 and fixed to the rod below the base 38. Fitted nut runner, and rotate the rod with an electric motor,
The nut runner is raised and lowered, and the upper part of the base 38 is
An elevating mechanism 61 (FIG. 7) is provided to move up and down from the upper surface.

As shown in FIG. 6, the turntable 39 is rotatable with respect to a base 38, and an electric motor 62 (FIG. 7) is embedded in the base 38.
Thus, the rotation shaft of the turntable 39 is rotated.

The transfer arm 30M (30S) is a scalar arm type robot hand in which a link mechanism is assembled by a transfer hand 31, a first arm 32, and a second arm 33, and is provided by a servo motor or the like. Actuator 63
(FIG. 7).

The transfer hand 31 is substantially concave when viewed from above.
Suction holes 34, 34 are formed at the fork of the bifurcated plate.
It is configured to suck and hold the wafer 10 on the transfer hand 31 by suction (FIG. 7).

Then, one transfer arm 30M has
A mapping sensor 35 is attached to an end of the transfer hand 31 opposite to the suction holes 34. Hereinafter, the transfer arm 30M is referred to as a master, and the other transfer arm 30S is referred to as a slave.

The mapping sensor 35 has a bifurcated tip, and has a "V" shape in plan view. The tip is a photoelectric sensor 35a, 35a. The arm 30M is bent and extended, and the mapping sensor 35 is brought close to the buffer cassette 5. Then, the base 38 is lowered, and the photoelectric sensors 35a
Search each shelf of the buffer cassette 5 with the
.. Are detected.

FIG. 7 is a block diagram showing a control structure of the automatic guided vehicle 1. The driving motors 8, 8, 9.
8, the elevating mechanism 61 for raising and lowering the base 38, the electric motor 62 for rotating the turntable 39, the actuators 63 for bending the transfer arms 30M and 30S, and the wafer The air pump 64 for sucking the air and the mapping sensor 35
The photoelectric sensors 35a and 35a are connected to a carrier controller 60 built in the vehicle body 2, and operate according to a predetermined procedure.

Next, the attitude adjusting device 4 will be described. As shown in FIG. 2 and FIG.
Are the casing 40, the mounting table 41, the orientation flat sensor 42
・ 42, Optical character reader (hereinafter “OC”)
R ") 43 and the like, and the casing 40
A pair of orientation flat sensors 42, 42 are disposed near the entrance, and a light transmitter 42 is provided on the ceiling surface.
a, a light receiver 42b is embedded in the floor. The two sets of the orientation flat sensors 42 are located at the position (or notch 10) of the orientation flat 10a of the 12-inch wafer 10L by the outer orientation flat sensor 42 (the opening entrance side of the casing 4).
b), and the orientation flat sensor 42 on the inner side (inside of the opening of the casing 4) detects the orientation flat 10a position (or notch 10b position) of the 8-inch wafer 10S.

An OCR 43 is buried on the floor surface and the back side of the opening of the casing 40.
The wafer 10 is set with the surface with the D mark 11 facing down, and the ID mark 11 is read by the OCR 43. The wafer 10 may be set with the surface of the ID mark 11 on the upper side. In this case, the OCR 43 is arranged on the ceiling surface or the back side of the opening of the casing 40, or
In consideration of the fact that the board surface of the wafer 10 is turned upside down in the working process, a pair of upper and lower OCRs 43 may be arranged on the ceiling surface of the opening of the casing 40 and the back side of the floor surface.

Also, on the floor of the opening of the casing 40,
A mounting table 41 on which the wafer 10 is mounted is provided. The mounting table 10 has a disk-like shape, and a plurality of ribs protrude concentrically and radially from the rotation center on the mounting surface to enhance the frictional effect with the wafer 10. Further, a suction hole 44 is provided in the rotation axis of the mounting table 41, and suction is performed by an air pump 66 (FIG. 7).
0 is adsorbed and held. Thus, when the mounting table 41 is rotated by the electric motor 65 (FIG. 7),
The wafer 10 is prevented from being blown off from the mounting table 41 by centrifugal force.

The electric motor 6 for rotating the mounting table 41
5 and an air pump 6 for sucking the wafer 10 through the suction hole 44
6, the orientation flat sensors 42, 42, and the OCR 4
3 is connected to the carrier controller 60 shown in FIG. 7 and operates according to a control signal from the carrier controller 60.

Next, the buffer cassette 5 will be described. As shown in FIG. 1, the buffer cassette 5 has a buffer base 50 with its opening facing forward (toward the transfer device 3).
Is placed on top. A plurality of shelves for holding the side ends of the wafers 10 are provided vertically on the left and right inner side surfaces in the buffer cassette 5, respectively, so that the wafers 10, 10... And

As shown in FIG. 2, a rotation fulcrum shaft 51 is provided at the rear of the lower surface of the buffer cassette 5, and the rotation fulcrum shaft 51 is supported at the rear of the buffer base 50. Also,
An electric cylinder 5 is provided near the center of the mounting surface of the buffer base 50.
2 is buried, and the cylinder rod 5 of the electric cylinder 52 is
The upper end 2a is connected to the rotation fulcrum shaft 51 via an arm 53.

In this way, the cylinder rod 52a is expanded and contracted, the rotation fulcrum shaft 51 is rotated, and the buffer cassette 5 is tilted back and forth. Stopper mechanisms 54F and 54B are provided at the front and rear positions on the side of the buffer cassette 5, and the wafers 10.
0... Are placed in a horizontal position (horizontal state), or the shelf is inclined forward and upward (in an inclined state).

The stopper mechanisms 54F and 54B are respectively provided with stopper pins 54 provided on the side of the buffer base 50.
a, 54a, and cylinders 54b, 54b vertically suspended from the buffer cassette 5 side.
4a and the cylindrical body 54b are brought into contact with each other so that the buffer cassette 5
Fix the posture of.

The front stopper pin 54a is erected vertically upward, while the rear stopper pin 54a is erected upward and rear. When the buffer cassette 5 is in a horizontal state, the front stopper mechanism is provided. When the buffer cassette 5 is in an inclined state, the stopper pin 54b of the rear stopper mechanism 5B is in contact with the cylinder 54a.
The 4B stopper pin 54b abuts on the cylinder 54a and is fixed in position.

The cylinders 54b, 54b are filled with anti-vibration rubber or the like, and absorb the impact when the stopper pins 54a come into contact with the cylinders 54b, so that the wafers 10, 10,.・ Do not rotate or shift position.

With such a configuration, when the automatic guided vehicle 1 is run, the buffer cassette 5 is set in the inclined state so that the wafers 10, 10,... I have.

Further, as shown in FIGS. 1 and 3, a stopper rod 55 is provided near the opening of the buffer cassette 5, and a groove is formed from the left end position of the upper and lower frames surrounding the opening to the center position. The upper and lower ends of the stopper rod 55 are engaged with the grooves.

The stopper rod 55 is usually located at the left end position of the buffer cassette 5, and when the buffer cassette 5 is tilted in an inclined state and the automatic guided vehicle 1 is run, a wire is wound by an electric motor 67 (FIG. 7). The stopper rod 55 is slid to the center position of the buffer cassette 5 so that the wafers 10 can be moved even when the automatic guided vehicle 1 suddenly starts or stops.
I try not to jump out of

Then, as shown in FIG. 7, the electric cylinder 52 for tilting the buffer cassette 5 and the electric motor 67 for sliding the stopper rod 55 are connected to the transport vehicle controller 60 and It operates according to a control signal from the car controller 60.

Further, photoelectric sensors 69, 69 provided on the vehicle body 2 of the automatic guided vehicle 1 are connected to the carrier controller 60. On the other hand, traveling rail 20
20 and the stocker 22 are provided with stop position markers at predetermined positions, and the automatic traveling automatic guided vehicle 1 uses the photoelectric sensor 69 to set a target stop position marker. When the detection is detected, a stop command is output from the carrier controller 60 to the drive motors 8, 8, 8, 8 of all the running wheels 9, 9, 9, 9, so that the automatic guided vehicle 1 stops at the target position. Is configured.

As described above, the transport vehicle controller 60
The various operations of the automatic guided vehicle 1 are controlled by this. Further, a communication device 68 is attached to the carrier controller 60, and communication is performed between the communication device 68 and the communication device 16 of the central controller 15 shown in FIG. Etc. are transmitted. The unmanned transport vehicle 1 transports the wafer 10 to the target processing device 21 and the stocker 22 by the transport vehicle controller 60 based on the transport command.

The central controller 15 is connected to a processing device controller 70 for controlling the processing device 21 via a control line. The processing device controller 70 is provided with a status recognition means 71 for recognizing a processing status in the processing device 21, a processing means 72 for performing an inspection process based on the ID information of the wafer 10, and the like. The situation recognizing means 71 recognizes the current situation of the wafer 10 to be processed, and before completion of the processing, a signal is sent from the processing apparatus controller 70 via the communication device 16 of the central controller 15 to the carrier controller. Sent to the processing unit 21 to inform the processing apparatus 21 that the next wafer 10 can be transferred.

Next, with reference to the flow charts shown in FIGS.
A series of operations for transferring 0 ... will be described.

As shown in FIG. 9, first, the automatic guided vehicle 1 moves the automatic guided vehicle 1 to a predetermined cassette 2 on the stocker 22.
It is moved to three positions (step S1). At this time, the transfer device 3 of the automatic guided vehicle 1 faces the cassette 23, and the wafers 10, 10...
Are stored with the side on which the ID mark 11 is engraved facing down.

Here, the base 38 is raised, the turntable 39 is rotated, the transfer arm 30M on the master side is turned, and the mapping sensor 35 attached to the transfer hand 31 is moved to the buffer cassette 5. Closer to the top shelf. Then, the base 38 is lowered and the transfer hand 31 is moved in parallel to the lowermost shelf position of the buffer cassette 5, and at this time, the photoelectric sensors 35a and 35
The mapping for detecting the presence / absence of the wafers 10 is performed for each shelf by a. Then, the detection result is output to the carrier controller 60, whereby the carrier controller 60 recognizes the number of the shelf from which the wafers 10 are not stored. (Step S2). At this time, the wafer shifts at the same time (obliquely)
It is also detected whether or not it is placed, and if it is out of position, no transfer is performed.

Then, the turntable 39 is set at 180
The transfer arms 30M and 30S are rotated to reverse the direction, and the suction holes 34 of the transfer hand 31 are directed toward the buffer cassette 5 (step S3).

At this time, if it is detected by the mapping that the shelf of the buffer cassette 5 is empty (step S4), the base 38 is raised and the transfer arm 3
0M is rotated and bent, the wafer 10 in the cassette 23 placed on the stocker 22 is scooped, the wafer 10 is sucked by the air pump 64, and the suction holes 34.3 of the transfer hand 31 are moved.
Then, the transfer arm 30M is bent and stretched and taken out of the cassette 23 (step S5).

Then, while securely holding the wafer 10 with the transfer hand 31, the base 38 is moved up and down to a predetermined height, and the transfer arm 30M is rotated and bent to move the transfer hand 31 to the buffer cassette. 5, after inserting both ends of the wafer 10 on the upper shelf, which has not been stored, the suction by the air pump 64 is released, and the transfer arm 30M is bent and stretched, and the wafer 10 is bent. The transfer hand 31 is pulled out from below, and the storage of the wafer 10 is completed (step S6).

Here, returning to step S4, if there is still room on the shelf of the buffer cassette 5, the next wafer 10 is similarly transferred.

On the other hand, if it is determined in step S4 that there is no empty space on the shelf of the buffer cassette 5, the buffer cassette 5 is rotated to the above-mentioned inclined state to fix the position.
Further, the stopper rods 55 prevent the wafers 10, 10,... Stored in all the shelves from jumping out (step S).
7). Then, the automatic guided vehicle 1 is caused to travel, and the automatic guided vehicle 1 is moved to the position of the processing device 21 (Step S).
8).

At this time, the transfer device 3 of the automatic guided vehicle 1
It faces the inlet 21a of the processing device 21, where
Raise the base 38 and move the transfer arm 3 on the master side.
0M, the uppermost wafer 10 in the buffer cassette 5 is scooped, the wafer 10 is sucked by the air pump 64, sucked and held by the suction holes 34 of the transfer hand 31, and the transfer arm 30M Is bent out and taken out of the buffer cassette 5 (step S9).

Then, the base 38 is lowered to a predetermined height, the turntable 39 is rotated by 180 °, the directions of the transfer arms 30M and 30S are reversed, and the transfer hand 31 holding the wafer 10 is positioned. It turns to the aligning device 4 side (step S10). Next, the transfer arm 30M is bent and extended, the transfer hand 31 is inserted into the posture adjusting device 4, and the wafer 10 is set on the mounting table 41.
Is released, the transfer arm 30M bends and stretches,
The transfer hand 31 is extracted from below the wafer 10 (step S11).

As described above, first, the wafer 10 is placed on the mounting table 41.
The wafer 10 is suctioned by an air pump 66,
Is sucked and held by the suction holes 44, and the mounting table 41 is rotated once. Thus, the orientation flat sensor 10 detects the position of the orientation flat 10a (or the position of the notch 10b) of the wafer 10 and the rotation locus drawn by the wafer 10, and outputs the detection result to the carrier controller 60 (step S12). .

By detecting the position of the orientation flat 10a (or the position of the notch 10b) of the wafer 10, the position of the ID mark 11 stamped at a predetermined position on the surface of the wafer 10 is calculated, whereby the position of the ID mark 11 is positioned above the OCR 43. Then, the mounting table 41 is rotated to perform the positioning.

The carrier controller 60 includes:
A rotation trajectory when the wafer 10 is set and rotated at a proper position on the mounting table 41 is input in advance, and the rotation trajectory of the eccentrically rotated wafer 10 is referred to in the rotation trajectory. , The rotation center of the mounting table 41 and the wafer 1
The deviation from the zero rotation center is calculated. Then, a correction value based on the calculation result is output from the carrier controller 60 to the actuator 63 of the transfer arm 30M, the suction of the wafer 10 by the suction hole 44 is released, and the wafer 10 is placed on the mounting table 41 by the transfer hand 31. Set again. As a result, the position of the ID mark 11 on the wafer 10 is accurately set at a position above the OCR 43 (step S13).

The setting method is different between the 12-inch wafer 10 and the 8-inch wafer 10. In the case of the former 12-inch wafer 10, the rotation center of the mounting table 41 and the rotation of the wafer 10 are different. Match the rotation center. On the other hand, in the case of the latter 8-inch wafer 10, the center of rotation of the wafer 10 is set to be shifted forward by a predetermined distance from the center of rotation of the mounting table 41, and the ID mark 11 of the wafer 10 is positioned immediately above the OCR 43. So that With such a configuration, the ID mark 11 of the 12-inch wafer 10 and the I mark of the 8-inch wafer 10 can be
It is possible to read both the D marks 11, and it is not necessary to provide the OCRs 43 for each size of the wafer 10, and it is possible to reduce the number of the relatively expensive OCRs 43, thereby reducing cost. Can be.

The OCR 43 reads the ID mark 11 attached to the board of the wafer 10 (step S14), and transmits the ID information from the communication device 68 of the automatic guided vehicle 1 to the communication device 16 of the central controller 15. Then, it is output to the processing device controller 70 of the processing device 21 (step S15). In this way, before the wafer 10 with the ID mark 11 is transferred to the processing apparatus 21, the ID information is input to the processing means 72.

Then, as shown in FIG. 10, the wafer 10 is sucked by the air pump 66 and the mounting table 41 is rotated.
The position of the zero orientation flat 10a (or the position of the notch 10b) is directed in a predetermined direction (step S16). As a result, the wafer 10 transferred to the processing apparatus 21 has its orientation flat 1
The transfer is performed with the 0a position (or the notch 10b position) always in a fixed direction.

Then, the transfer arm 30M is bent and stretched,
The wafer 10 on the mounting table 41 is scooped, the wafer 10 is sucked by the air pump 64, and the suction holes 34
Suction and holding at 34, bending and extending the transfer arm 30M,
It is taken out of the posture adjusting device 4 (step S17).

Next, in the plan view shown in FIG. 3, the turntable 39 is rotated counterclockwise by 90 °, the base 38 is raised and lowered to a predetermined height, and the transfer arm 30M is bent and stretched.
The transfer hand 31 holding the wafer 10 is inserted into the inlet 21a of the processing device 21. In this way, the wafer 10 before the inspection processing is set in the wafer loader of the inlet 21a, and the suction by the air pump 64 is released.
M is bent and extended, and the transfer hand 31 is extracted from below the wafer 10 (step S18).

Here, if the wafer 10 is the first wafer 10 to be processed (the first wafer 10) (step S19), the turntable 39 is directly turned 90 ° counterclockwise in plan view. After rotation, the process returns to step S9, and the second wafer 1
Then, the same processing as that for the first wafer 10 is performed.

On the other hand, the wafer 10 is the first wafer 1
If it is not 0 (step S19), that is, if the wafer 10 is the second or subsequent wafer 10, the wafer 1 transferred to the processing apparatus 21 before the wafer 10
0 has already been inspected and is waiting at the wafer unloader at its inlet 21a. The wafer 10 held by the transfer arm 30M on the master side is placed on the wafer loader of the processing apparatus 21 (step S18). Then, the wafer 10 subjected to the inspection processing is taken out of the wafer unloader by the other transfer arm 30S on the slave side (step S20).

After the inspection process, the wafer 10 is transferred to the transfer arm 30.
After being picked up by the transfer hand 31 of S, sucked and held by the suction holes 34, 34 by the air pump 64, the transfer arm 30S is bent and stretched as it is and taken out of the processing apparatus 21, and then the turntable 39 is In the plan view shown in FIG.
° Rotate counterclockwise.

Here, the buffer cassette 5 has a shelf (my space) in which the wafer 10 held by the transfer arm 30S on the slave side is originally stored, and a shelf below it. Transfer arm 3 on the shelf of the my space
After inserting the transfer hand 31 of OSS, placing both ends of the wafer 10 on the shelf of the my space, the suction by the air pump 64 is released, the transfer arm 30S is bent and extended, and the transfer arm 30S is transferred from below the wafer 10. The loading hand 31 is removed, and the wafer 10 subjected to the inspection processing is stored in the buffer cassette 5 (step S21).

Here, the wafer 10 subjected to the inspection processing stored in the buffer cassette 5 is the second wafer 10 subjected to the inspection processing from the bottom which was originally stored in the second stage from the bottom of the buffer cassette 5. If it is not (the second last wafer 10) (step S22), the wafer 10 after the inspection process is moved by the slave-side transfer arm 30S.
Is stored, and the wafers 10 stored in the two lower shelves of the shelf in My Space in which the inspected wafers 10 are stored are scooped out by the transfer arm 30M on the master side. The wafer 10 is sucked and held by the suction holes 34, 34 by the air pump 64, and the transfer arm 30M is bent and stretched as it is to be taken out of the buffer cassette 5 (step S23).
Returning to 0, the processing is performed.

Thus, the wafers 10, 10...
However, in the step S21, the wafer 10 after the inspection process stored in the buffer cassette 5 is processed.
However, in the case of the second last wafer 10, here,
The turntable 39 is rotated clockwise by 90 ° in the plan view shown in FIG. 3, and the transfer device 3 is made to stand by until the inspection processing of the last one wafer 10 is completed. (Step S24), the last one wafer 10 placed on the wafer unloader of the inlet 21a is taken out by the transfer arm 30S on the slave side (Step S2).
5). In this manner, the last one wafer 10 is scooped by the transfer hand 31 of the transfer arm 30S, sucked and held by the suction holes 34, 34 by the air pump 64, and bends and stretches the transfer arm 30S as it is. After being taken out from 21, the turntable 39 is viewed from above as shown in FIG.
Rotate 90 ° counterclockwise.

At this time, only the lowermost shelf of the buffer cassette 5 is empty, and the transfer hand 31 of the transfer arm 30S holding the last one wafer 10 is inserted into the lowermost shelf. Then, after placing both ends of the last one wafer 10 on the lowermost shelf, the suction by the air pump 64 is released, the transfer arm 30S is bent and extended, and the transfer hand 31 is placed from below the wafer 10. And take out the buffer cassette 5
The last one wafer 10 is stored in the inside (step S2).
6). In this way, the last one wafer 10 is stored in the lowermost stage of the buffer cassette 5, and a series of processing is completed.

In the above embodiment, the automatic guided vehicle 1 stops in front of one processing unit 21 and the buffer cassette 5
Although the wafers 10 stored in the wafers are inspected by the same processing apparatus 21, the wafers 10 may be inspected by different processing apparatuses 21. For example, the central controller 15
When receiving a signal indicating that the processing is completed by the status recognition means 71 of the processing device 21, the communication device 16 creates a transport command based on the information and sends the transport command to the transport vehicle controller 60 from the communication device 16 via the communication device 68. Send a transfer command.
When receiving the transfer command, the transfer vehicle controller 60 checks whether the wafer 10 before inspection is stored in the buffer cassette 5, and moves to the target processing device 21 according to the transfer command if the wafer 10 is stored. If all the stored wafers 10 have been inspected, the process returns to the stocker 22, and the inspected wafers 10 in the buffer cassette 5 are moved to a predetermined cassette 23, and the wafers 10 before inspection are moved to the buffer cassette 5. The mounting arm 30M is operated, and if necessary, both 30M and 30S are operated to transfer. And
It moves to the target processing device 21 to execute the transfer command.

The automatic guided vehicle 1 arrives before the processing of the processing apparatus 21 is completed and prepares for transfer of the wafer 10.
That is, the wafers 10 before inspection of the buffer cassette 5
Is transferred to the posture adjusting device 4 by the transfer arm 30M, and the posture adjusting device 4 is operated so that the wafer 10 has a predetermined posture and the ID information of the wafer 10 is recognized. I do. More specifically, first, the wafer 10 is transferred from the buffer cassette 5 to the posture adjusting device 4. That is, the transfer hand 31 of the transfer arm 30M
Turns the turntable 39 so as to face the buffer cassette 5, and extends the transfer arm 30M.
Then, the elevating mechanism 61 is lifted to scoop up the wafer 10 from the buffer cassette 5, and the air pump 64 is operated to transfer the wafer 1 to the transfer hand 31.
0 is adsorbed. Then, after the transfer arm 30M is expanded and contracted to a predetermined position (standby position), the turntable 39 is turned so that the transfer hand 31 faces the posture adjusting device 4, and the transfer arm 30M is extended. Then, the elevating mechanism 61 is lowered, the air pump 64 is stopped, and the wafer 10 is mounted on the mounting table 41 of the posture adjusting device 4, and the transfer arm 30M is shortened to a predetermined position.

Next, the ID information of the wafer 10 is recognized.
That is, the mounting table 41 is held in a state where the wafer 10 is sucked and held.
And the orientation flat sensors 42
Activate The orientation flat sensors 42, 42
The orientation of the wafer 10 is recognized from the turning trajectory of the outer periphery, and the position information is sent to the carrier controller 60 to determine the position of the ID mark 11. The carrier controller 60
Based on the obtained position information, the ID mark 11
The wafer 1 is moved by the transfer arm 30M so that
Move 0. Then, the OCR 43 is activated, and the ID
The ID information of the mark 11 is read and stored in the carrier controller 60.

Next, a position adjustment for transferring the wafer 10 in a predetermined position designated by the processing apparatus 21 is performed. That is, the wafer 10 is transferred onto the mounting table 41 again, and the transfer arm 30M is shortened to a predetermined position. The mounting table 41 is turned again, and the orientation flat sensors 42, 42 are operated again.
The position of (notch 10b) is accurately recognized. Then, the transfer arm 30M is operated based on the obtained position information, and the wafer 10 is transferred again so that the wafer 10 has a predetermined posture at a predetermined position of the mounting table 41.

Then, the wafer 10 is immediately transferred to the processing apparatus 2.
Then, the wafer 10 is held in a standby state so that the wafer 10 can be transferred to the wafer. That is, the wafer 10 in the predetermined posture is picked up by the transfer hand 31, sucked and held, and the transfer arm 30M is shortened to the predetermined position. Then, the transfer arm 30M is connected to the processing device 2
The turntable 39 is turned so as to be opposed to 1.

For the sake of controlling the transfer arm 30M (30S), the orientation flat sensors 42
After aligning the position of the ID mark 11 for the CR 43 and moving it to a position directly above the OCR 43 to recognize the ID, the orientation flat sensors 42 and 42 are operated again to transfer the wafer 10 to the processing apparatus 21. Although the orientation is adjusted, the transfer arm 3 is operated so that the orientation flat sensors 42 are operated so that the wafer 10 is in a predetermined orientation.
The wafer 10 is accurately placed on the mounting table 41 at 0M (30S), the wafer 10 is sucked and held by the transfer hand 31 of the transfer arm 30M (30S), and the transfer arm 30M (30S) is Alternatively, the ID mark 11 may be moved right above the OCR 43 to read the ID mark 11 with the OCR 43, the transfer arm 30M (30S) may be shortened to a predetermined position, and the turntable 39 may be turned.

In order to read the ID mark 11 of the 8-inch wafer 10S and the ID mark 11 of the 12-inch wafer 10L using the common operation procedure and the common OCR 43, the transfer arm 30M uses the ID mark 11 of the OCR 43. When the wafer 10 is arranged at a predetermined position on the mounting table 41 in a predetermined posture, the OCR 43 is arranged so that the ID mark 11 can be read, and the wafer 10S of 8 inches is placed. In case of OCR4 with transfer arm 30M
3 and the OCR 43 moves the ID mark 11 on the 12 inch wafer 10L without any special movement.
May be read.

When the inspection processing is completed, the processing device 21 communicates with the automatic guided vehicle 1 to check whether the preparation for transfer is completed. If it is completed, the processing apparatus 21 transmits the ID information of the inspected wafer 10 to the AGV 1 and receives the ID information of the wafer 10 to be inspected next from the AGV 1. . These pieces of information are also transmitted to the central controller 15.

Then, the processing device 21
Open the door provided in a. Since the inspected wafer 10 is placed in the inlet 21a, the wafer 10 is taken out by the transfer arm 30S, and then the wafer 10 before inspection is placed by the transfer arm 30M. In the case where the station of the wafer 10 provided in the inlet 21a is common for the wafer before inspection and for the wafer after inspection, the inspected wafer 10 is first taken out, and then the wafer 10 to be inspected is taken out.
Must be placed on the station. If the stations are separate for the wafer before inspection and for the wafer after inspection, it is possible to take out the wafer 10 after inspection and mount the wafer before inspection in parallel. Even when the station is common, the unloading operation and the mounting operation of the wafer 10 can be partially performed in parallel.

When the processing apparatus 21 confirms that the mounting of the wafer 10 is completed, the processing apparatus 21 closes the door of the intake port 21a, and evacuates the intake port 21a, for example, to a state where the processing apparatus 21 can perform inspection. To The automatic guided vehicle 1 transfers the inspected wafer 10 to, for example, a place where the wafer 10 transferred to the processing device 21 is stored in the buffer cassette 5.

Upon receiving a new transfer command from the central controller 15, the automatic guided vehicle 1 moves toward the target processing device 21. This transfer command is sent to the central controller 1
5 to the automatic guided vehicle 1 at any time. When a plurality of transport commands are transmitted, the transport vehicle controller 60 schedules the moving order and executes the transport commands. This moving order is created based on the scheduled end time of the inspection of each processing device 21 included in the transfer command, and the scheduled end time is earlier. The transfer command is accumulated by the central controller 15, the central controller 15 schedules the transfer command, and the transfer of the automatic guided vehicle 1 from the central controller 15 is completed when the transfer processing of the automatic guided vehicle 1 is completed. Only one message may be transmitted to the controller 60.

As described above, the automatic guided vehicle 1 is moved before the inspection of the processing apparatus 21 is completed, and the wafer 1 before the inspection is moved.
By reading the ID information of “0” and preparing and waiting for the wafer 10 to be transferred to the processing apparatus 21 in a predetermined posture, the time for opening the door of the inlet 21 a of the processing apparatus 21 can be shortened. It is possible to minimize the decrease in cleanliness in the intake port 21a,
Operating time can be improved. In order to further shorten the time for opening the door, the automatic guided vehicle 1 is provided with a pair of transfer arms 30M and 30S, and one of the transfer arms 30S (30M) has been inspected in the processing device 21. Of the other transfer arm 30M
In (30S), the wafer 10 before inspection is placed. Since a plurality of wafers 10 can be stored in the buffer cassette 5 and a plurality of processing devices 21 are provided along the traveling path of the automatic guided vehicle 1, 1 can be moved appropriately,
The time for resting the processing devices 21 waiting for inspection can be shortened without providing each processing device 21 with a posture adjusting means or an ID reading means.

In the present embodiment, the processing device 21
Although it was an inspection processing device, it is not limited to inspection processing.
A processing device such as etching of the wafer 10 may be used.

[0077]

As described above, the present invention has the following advantages. That is, in an automatic guided vehicle equipped with a transfer means for transferring a wafer and a fixed cassette for temporarily storing the wafer, the transfer means transfers the wafer to the cassette. By setting the cassette so that the wafer can be taken in and out in a horizontal state, the wafer can be transferred by the transfer means that moves in a substantially horizontal direction, and the transfer means is constituted by a relatively simple mechanism. can do. On the other hand, when running the automatic guided vehicle, the cassette is set so as to prevent the wafer from jumping out of the cassette, so that the wafer in the cassette can be stopped even when the automatic guided vehicle is suddenly stopped or suddenly started. The reliability can be improved without spilling. In addition, since the wafers are temporarily stored in the cassette, a plurality of wafers can be stored in the cassette at one time, and the wafers can be efficiently transferred, thereby improving workability. Further, since the cassette is fixed to the automatic guided vehicle, a transfer means for transferring the cassette is not required, so that the number of parts can be reduced and the cost can be reduced.

Further, by tilting the cassette on the automatic guided vehicle, the wafer inside the cassette can be prevented from jumping out when the automatic guided vehicle is transported. Improvement can be achieved.

Further, as in the third aspect, a rotation fulcrum is provided on the side close to the back surface of the cassette so that the cassette can be tilted, and the position of the cassette is fixed while the wafer inside the cassette is horizontal. Thus, the wafer can be transferred by the transfer means that moves in a substantially horizontal direction, and the transfer means can be configured with a relatively simple mechanism. Further, by fixing the position of the cassette in a state in which the wafers inside the cassette are inclined to the rear side (back side) of the cassette, the wafers in the cassette can be prevented from jumping out of the cassette when the automatic guided vehicle travels. Improvement can be achieved. And then
The mechanism for fixing the position of the cassette when the wafers inside the cassette are horizontal or when the wafers inside the cassette are inclined toward the back of the cassette can be easily configured by a stopper or the like.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an automatic guided vehicle 1 in a clean room.

FIG. 2 is a side sectional view of the automatic guided vehicle 1.

FIG. 3 is a plan view of the same.

FIG. 4A is a plan view of a wafer 10 having an orientation flat 10a. (B) is a plan view of the wafer 10 having the notch 10b.

FIG. 5 is a side sectional view of the automatic guided vehicle 1 when the base 38 is raised.

FIG. 6A is a plan view of the automatic guided vehicle 1 when the wafer 10 is transferred to the attitude adjusting device 4. (B) is a wafer 10
FIG. 4 is a plan view of the automatic guided vehicle 1 when the vehicle is transferred to the buffer cassette 5. (C) is a plan view of the automatic guided vehicle 1 when the wafer 10 is taken out from the buffer cassette 5.

FIG. 7 is a block diagram showing a control configuration of the automatic guided vehicle 1.

FIG. 8 is a block diagram showing a control configuration of the automatic guided vehicle system.

FIG. 9 is a flowchart showing a transfer process (first half) of the wafer 10 by the automatic guided vehicle 1;

FIG. 10 is a flowchart showing a transfer process (second half) of the wafer 10 by the automatic guided vehicle 1;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 automatic guided vehicle 3 transfer device 4 attitude adjustment device 5 buffer cassette 10 wafer 11 ID mark 21 processing device 22 stocker 23 cassette 30 M / S transfer arm 34 suction hole 35 mapping sensor 41 mounting table 42 orientation flat sensor 43 OCR 44 suction hole Reference Signs List 50 Buffer table 51 Rotating fulcrum shaft 52 Electric cylinder 54FB Stopper mechanism 55 Stopper rod

Continuing from the front page (72) Inventor Shuji Akiyama 5-3-6 Akasaka, Minato-ku, Tokyo TBS Release Center Tokyo Electron Limited F-term (reference) 3C007 AS02 AS24 BS15 CS04 CT04 CT05 CV07 CW07 CY03 DS03 ES03 FS01 HS27 JS07 JU17 KV11 MS14 NS09 NS13 3F022 AA08 CC02 EE05 KK10 KK20 LL12 MM08 MM44 MM66 MM67 QQ11 5F031 CA02 DA01 EA09 FA01 FA07 FA09 FA15 FA18 GA04 GA06 GA08 GA45 GA49 GA50 GA54 GA58 GA59 PA35 JA35 JA34 JA35

Claims (3)

[Claims] In an automatic guided vehicle equipped with transfer means for transferring a wafer and a fixed cassette for temporarily storing the wafer, when the transfer means transfers the wafer to the cassette, the wafer is transferred to the cassette. An unmanned carrier characterized by setting a cassette so that it can be taken in and out in a horizontal state, while setting the cassette so as to prevent wafers inside the cassette from jumping out when running the unmanned carrier. 2. The automatic guided vehicle according to claim 1, wherein the cassette is tilted on the automatic guided vehicle to prevent the wafer from jumping out of the cassette. 3. The cassette is configured to be tiltable by providing a rotation fulcrum on a side close to the rear surface of the cassette, and the wafer inside the cassette is horizontal, or the wafer inside the cassette is moved to the cassette rear side (back side). 3. The automatic guided vehicle according to claim 2, wherein the cassette is fixed in a position where the cassette is tilted to the position (1).