JP2003243472A - Method for controlling travel of conveying cart in vacuum chamber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for controlling a travel of a conveying cart in a vacuum chamber, capable of transferring a substrate safely and reliably under a special environment where visual checking cannot can be performed. <P>SOLUTION: An abutment block is disposed at a location where a cart cannot advance ahead of a target stop position where a substrate is transferred from the cart to the other member in a vacuum processing chamber (a); a distance enough to lower a propulsive force of the cart before the cart abuts on the abutment block is set (b); the revolution of a pinion or a revolution of a pinion drive source is detected to calculate a location of the conveying cart based on the detected revolution (c); when a distance between a calculated position and the target stop position is equal to or smaller than the distance set by the step (b), the drive torque of the pinion is decreased to lower the propulsive force of the cart (d); and the cart is set to abut on the abutment block by the smaller propulsive force than when normally conveying, and the pinion is continually driven at low torque only in a predetermined period to continue to advance the cart in a state of abutting on the abutment block (e). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling traveling inside a vacuum chamber of a carrier for transporting a glass substrate in a vacuum processing chamber for performing CVD film formation or the like.

[0002]

2. Description of the Related Art A conventional bogie traveling control method will be described with reference to FIG. The vacuum processing system has a gate valve 112.
A vacuum processing chamber 101, a bogie rotation chamber 102, and a vacuum processing chamber 103 are connected in series via the. Carrier 6
The pinion 172 meshes with the rack 64 formed on the side surface and travels on the rail 8 by the driving force transmitted from the pinion 172. Pinion 17
2 are arranged at predetermined intervals along the rail 8 and each of them is controlled by the controller 180.
It is designed to be independently driven by 0A to 170D.

The controller 180 controls the stepping motors 170A to 170A so that all the pinions 172 on the rails 8 arranged on the same line are rotated in a synchronized manner.
Control 70D. The transport carriage 6 passes from the vacuum processing chamber 101 to the carriage rotation chamber 102 through the gate valve 112 that is opened and closed.
Then, the glass substrate G is transferred from the carriage rotation chamber 102 to the vacuum processing chamber 103, and the substrate G is transferred to a film forming unit (not shown) in the vacuum processing chamber for film forming processing.

[0004]

However, since the vacuum processing chamber for performing processing such as plasma CVD, sputtering, and dry etching on the substrate is surrounded by the outer wall of the chamber, the operator can visually confirm the transfer carriage. Is in an environment where it cannot be stopped at the target position. Therefore, the conventional vehicle traveling control method has the following problems (1) to (3).

(1) Even if the positioning is electrically completed in the control system between the controller / stepping motor / pinion, it is possible to appropriately cope with mechanical backlash at the bogie stop position at the substrate transfer place. Therefore, the transfer operation of the substrate becomes uncertain, and there is a possibility that the substrate may be damaged due to a collision with another member or a drop.

(2) In order to guarantee the reproducibility of delivery, the same result is obtained when the same operation is repeated.
High positional accuracy is required so that the stop position of the carriage is within ± 1 mm with respect to the target stop position (delivery position).

(3) It is necessary to confirm the target stop position of the carrier every time the apparatus is maintained, and the time required for the maintenance increases accordingly.

The present invention has been made in order to solve the above problems, and provides a method for controlling traveling in a vacuum chamber of a carrier truck that can safely and reliably transfer substrates in a special environment where visual confirmation is impossible. The purpose is to do.

[0009]

According to a method of controlling traveling of a carriage in a vacuum chamber of a carriage according to the present invention, a plurality of pinions arranged at predetermined intervals along a rail are driven by being engaged with a rack of the carriage. In a vacuum chamber traveling control method of a transfer vehicle for transmitting a force to transfer a substrate held by the transfer vehicle to a plurality of vacuum processing chambers, (a) the substrate is transferred from the transfer vehicle to another member in the vacuum processing chamber. The contact stop block is arranged at a position where the transfer carriage cannot move forward from the target stop position, and (b) a margin is provided to reduce the propulsive force of the transfer carriage until the transfer carriage hits the contact stop block. The distance is set, (c) the rotation speed of the pinion or the rotation speed of the pinion drive source is detected, and the position of the carrier is calculated based on the detected rotation speed, and (d) the target stop position is calculated from the calculated position. When reduced same as or than the distance set in the distance in said step (b),
The driving torque of the pinion is reduced to reduce the propulsive force of the carrier vehicle, and (e) the carrier vehicle is abutted against the stopper block with a smaller propulsive force than during normal transportation, and the pinion is lowered for a predetermined time. Continue to drive with torque,
It is characterized in that the transport carriage is continuously moved forward while being abutted against the stopper block.

In this case, it is preferable that the set distance in the step (b) is 90 to 110 mm. Since the steady speed of the carrier truck is 200 to 500 mm / sec, there is a time margin of 0.2 to 0.5 seconds before the carrier truck hits the stopper block after traveling the set distance. During this period, the control operation for switching the drive of the pinion drive source (servo motor) from high torque to low torque is completed.

Further, in the step (e), while the carrier truck is abutting against the stopper block, the virtual travel distance which the carrier truck would have advanced is assumed to be 100 to 300 mm assuming that there is no corresponding stopper block. It is preferable.

Further, in the step (d), it is preferable to reduce the rotation speed of the pinion drive source to decelerate the carriage. The total weight of the carrier is 1 when the boards are loaded.
Since the weight is over 0 kg, the inertial force is large. Therefore, even when the propulsive force (driving torque) transmitted from the pinion to the dolly is reduced, a large impact is generated when the transport dolly collides with the abutment block, which is transmitted to the substrate as vibration. This is because it is necessary to reduce as much as possible.

Further, the rotation angle of the servomotor drive shaft is feedback-controlled by detecting the motor rotation speed by an attached encoder, the gear teeth of the pinions arranged on the same line are aligned, and the pinion and the rack are synchronously engaged. Let Since the motors are synchronously controlled in this manner, the impact at the moment when the pinion meshes with the rack is reduced, and the vibration transmitted to the truck is reduced. Particularly when a large-sized substrate is conveyed, it is preferable to drive at a high torque and a low speed, because the dolly receives an impact when the pinion / rack is engaged and the vibration is transmitted to the substrate.

In the vacuum processing chamber, plasma CV is applied to the substrate.
D It may be a film forming chamber for film formation, it may be a dolly rotation chamber that rotates the transfer dolly to change the transfer direction of the substrate, or the transfer dolly enters from the atmosphere side to the vacuum side. It may be a load chamber or an unload chamber in which the carrier truck goes out from the vacuum side to the atmosphere side.

When the vacuum processing chamber is a film forming chamber, the predetermined time of the step (e) is the time until the transfer of the substrate from the carrier to other members is completed, and the step (e) is further performed. After completing the transfer of the substrate in (4), the pinion is rotated in the reverse direction, and the transport carriage is withdrawn from the film forming chamber.

[0016]

Various preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, in the cluster type vacuum processing system 1, the carriage rotating chamber 16 as a common transfer chamber.
Is arranged in the center, and a plurality of vacuum processing chambers 10,
18 and 20 are arranged in a radial pattern.
The communication passage chambers (intermediate chambers) 19 are connected to each other.

Of the vacuum processing chambers, the load chamber 10 and the unload chamber 20 are provided with a gate valve mechanism 12 on the front side for shutting off an opening between the chamber and the external transfer path in the atmosphere, and a common transfer chamber in the vacuum atmosphere on the rear side. The gate valve mechanism 12 for blocking the opening between the gate valve 16 and the gate valve 16 is provided. Gate valve mechanism 12
2, as shown in FIG. 2, a pair of left and right loading / unloading ports 12a, 1
It is provided with a gate valve that independently opens and shuts off 2b and a cylinder that drives each gate valve.

Among the vacuum processing chambers, the plurality of film forming chambers 18 block the openings between the film forming chambers 18 and the common transfer chamber 16.
It has each. A door that can be opened and closed is attached to the back side of each film forming chamber 18, and the inside of each film forming chamber 18 can be maintained by opening the door. The door is attached to each chamber so that it can be opened or closed manually or electrically, and a seal member is interposed between the frame wall forming each chamber and the door. A part of the plurality of film forming chambers 18 may be used as a preliminary chamber. The spare room
It is needless to say that it is used as a film forming chamber, but it may be used as a standby chamber for temporarily holding (retracting) the transport vehicle 6 or preliminarily heating the substrate G before film forming processing. It may be used as a preheating chamber or a cooling chamber for cooling.

The floor of the common transfer chamber 16 is the turntable 1
The turntable 17 rotates the carriage 6 on the rail 8 in a horizontal plane so that the carriage 6 can be turned in any direction by 360 °.

As shown in FIG. 2, a pair of parallel rails 8 are laid so as to be connectable to the rotating rails 8 in the carriage rotating chamber 16 from the atmospheric conveying path through the load chamber 10, and the conveying carriages 6 are mounted on the rails 8. It is designed to drive one car at a time. The rails 8 in the load chamber 10 are respectively provided on the extension lines of the rails 8 of the atmosphere transfer path, and the transfer carriage 6 is provided with the gate valve mechanism 12
The rail 8 of the atmosphere transfer path can be transferred to the rail 8 of the vacuum transfer path through the step.

Each of the transport carriages 6 independently transfers the substrate G 1
It is designed to be held and conveyed one by one. That is, the carriage 6 is provided with a pair of support columns 62 and a plurality of support claws (not shown) on the main body frame 61, and thereby holds one glass substrate G in an upright posture with a slight inclination. By the way, the size of the glass substrate G is, for example, 1 m square. 1m
The square glass substrate G has a weight of more than 10 kgf, which is a considerable weight.

The carrier 6 holding the substrate G enters the carrier rotating chamber 16 from the external carrier path through the load chamber 10.
After being rotated by the turntable 17 and aligned with the film forming chamber 18, after entering the film forming chamber 18 to form a film on the substrate G,
It passes through the carriage rotation chamber 16 and the unload chamber 20 and exits to the external conveyance path.

As shown in FIGS. 3 and 4, a plurality of pinions 72 are provided near the side of the rail 8 at predetermined intervals. These pinions 72 are arranged at positions where they can mesh with the racks 64 formed on the side surfaces of the carrier truck 6.

As shown in FIG. 3, each pinion 72 is connected to the rotary drive shafts of the servomotors 70A and 70B disposed below the conveying path, and the servomotors 70A and 7B are connected to the rotary drive shafts.
The pinions 72 are driven independently by 0B. Encoders 75 are attached to the servomotors 70A and 70B, respectively, and signals for detecting the motor rotation speed are sent to the controller 80, respectively. Although the encoder 75 that detects the motor rotation speed is used in the present embodiment, the present invention is not limited to this, and another encoder may be used to detect the pinion rotation speed. .

The stopper block 77B is attached only to the maintenance door side of the film forming chamber and to the trolley rotating base in the trolley rotating chamber, and does not have an up-and-down mechanism by a cylinder. It is fixed at.

The film forming chamber 18 is provided with two sets of equipment elements required for plasma CVD film formation, and a film forming unit and a heater unit (not shown) are arranged so as to face each other so as to sandwich the substrate transfer path from both sides. There is.

The heater unit includes a planar heater element and a heater cover that covers the heater element. The heater cover is for protecting the heating surface of the heater element, and is supported by the pressing mechanism. The pressing mechanism is a mechanism that moves the heater cover toward the film forming unit.

The film forming unit is provided with a ladder electrode with a gas supply function, a film forming unit cover, a temperature control heater, a substrate pressing plate, and an exhaust passage. A high frequency power source and a gas supply source are connected to the ladder electrode. The high frequency power source applies a high frequency of a predetermined frequency to the electrodes to generate plasma between the electrodes and the substrate G. A process gas containing silane as a main component is contained as a reactive gas in the gas supply source.

A second stopper block 77B is fixed on the base surface of the rail 8 with bolts and nuts at a target stop position in the film forming chamber 18. The bolt hole is formed in a long hole so that the mounting position of the second contact-stop block 77B can be finely adjusted. The transport carriage 6 enters into the film forming chamber 18 from the carriage rotation chamber 16, hits against the second stopper block 77B, and is stopped at the target stop position (that is, the substrate transfer position).

The controller 80 controls the length of the transfer path in each part of the system, the distance to the contact blocks 77A and 77B in the vacuum processing chamber, the processing recipe of the substrate G, and the predetermined driving torque T of the servomotors 70A and 70B.
1, T2, rotation speeds V1, V2, etc. are provided as initial data, and based on the initial data and the detection signals input from each encoder 75, each servo motor 70A,
The drive of 70B is controlled respectively. Further, the controller 80 includes the pinion drive motor 70 provided along the rails 8 arranged in series on the same line.
A and 70B are synchronously driven and controlled. Further, the controller 80 is also configured to control the length of time during which the transport carriage 6 continues to be in contact with the stopper block 77B.

As shown in FIG. 5, the carrier truck 6 includes a main body frame 61, a pair of columns 62, and a plurality of roller wheels 63. The rack 6 is provided on one side of the body frame 61.
4 is formed, and the above-mentioned pinion 72 is engaged with this. The pair of support columns 62 are provided upright on the main body frame 61 so as to be inclined about 10 ° with respect to the longitudinal orthogonal axis of the main body frame 61. The mutual distance between the columns 62 is slightly larger than the long side of the substrate G, and the substrate G is hung between the pair of columns 62. The columns 62 are firmly fastened to the main body frame 61 so as to bear the weight of the substrate G. The support column 62 and the main body frame 61 are made of a high-strength and strong metal material such as stainless steel. Multiple roller wheels 6
3 is rotatably rollingly contacted with each part of the rail 8 having a T-shaped cross section, and is supported by a buffer mechanism for absorbing vibrations and shocks transmitted to the body frame 61 of the carriage.

Next, a case where the glass substrate G is transferred by the transfer carriage 6 in the cluster type vacuum processing system 1 will be described with reference to FIGS. 3 and 6.

The transport carriage 6 receives the substrate G from a roller frame mechanism (not shown) on the atmospheric transport path, enters the load chamber 10 through the atmospheric transport path, and stops at the target stop position in the load chamber 10. As a stopping method, a method is used in which a stop position is set in the servo motor in advance and the servo motor is stopped based on the set position data.

When the controller 80 receives the signal of YES from the carriage rotating chamber 16, it sends a signal to each power source of the gate valve mechanism 12 and the pinion driving servomotor 70 to open the gate valve and rotate the pinion 72. Drive it. As a result, the carriage 6 enters the carriage rotating chamber 16 from the load chamber 10.

Further, the controller 80 sends a signal to the servo motor to switch the drive of the pinion 72 from a constant speed / steady torque to a low speed / low torque, and abuts the transport carriage 6 against the stopper block 77A, so that the inside of the carriage rotation chamber is stopped. Stop at the target stop position. This target stop position is substantially in the center of the turntable 17. Next, the transport carriage 6 is rotated by the turntable 17, the transport direction is aligned with the film forming chamber 18, and preparation for entering the film forming chamber 18 is completed.

When preparations are completed in the bogie rotating chamber, the controller 80 causes the gate valve mechanism 12, the servomotor 70A,
A signal is sent to each power source of 70B, the gate valve is opened, and the pinion 72 is driven to rotate. As a result, the carriage 6 enters the film forming chamber 18 from the carriage rotating chamber 16 and
It hits the fixed stopper block 77B and stops at the target stop position in the film forming chamber.

Next, a case in which the transport carriage 6 enters the film forming chamber 18 and leaves the film forming chamber 18 will be described in detail with reference to FIG.

As shown in FIG. 6 (a), the controller 80 causes the motor 70B to drive the steady torque T at the timing t1.
1, the driving of the motor 70B is switched to the low torque T2 at a timing t2 after a lapse of a predetermined time, and the transport carriage 6 is driven.
Drive with low torque.

Further, the controller 80 is shown in FIG.
As shown in, the motor 70B is started at the steady speed V1 at the timing t1, and the driving of the motor 70B is switched to the low speed V2 at the timing t2 after the elapse of a predetermined time.
Run at low speed.

The carrier truck 6 hits the stopper block 77B at a timing t3 after a lapse of a predetermined time. The controller 80 continues to supply power to the motor 70B until the predetermined time (time t3 to t6) elapses, and continues to drive the pinion 72. However, since the carriage 6 is prevented from moving further by the stopper block 77B, the pinion 72 cannot rotate while being bitten in the rack 64.

At the timing t2 when the drive torque of the motor 70B is switched, the carrier truck 6 is rotated at the motor rotation speed V.
When the vehicle travels at 2 (average speed), the distance from the current position of the trolley to the contact block 77B at the time of drive switching is set to 100 mm. That is, the controller 80 measures the distance from the stop position (position of the stopper block 77A) in the carriage rotation chamber to the target stop position (position of the stopper block 77B) in the film forming chamber, the motor rotation speed V1 (average speed) in the first half. , The second half of the motor rotation speed V2 (average speed), the time from the timing t1 to t3, and the virtual distance of 100 mm until reaching the abutment block 77B are substituted into a predetermined mathematical expression to calculate the timing t2, At the timing t2, a signal for switching the driving of the motor 70B to the low torque T2 / low speed V2 is sent.

Further, the controller 80 is shown in FIG.
As shown in, a signal is sent to the delivery mechanism on the film forming unit side and the delivery mechanism on the trolley side at a timing t4 after the trolley 6 hits the stopper block 77B. The pressing mechanism moves the heater cover forward and close to the substrate G on the dolly 6, releases the restraint of the substrate G by the holding claws, and transfers the substrate G from the support arm 62 of the dolly onto the support protrusion of the heater cover. During the transfer time t4 to t5 of the substrate G, the carriage 6 continues to move forward at a low speed and low torque, so that the stop position of the carriage 6 in the film forming chamber 18 is exactly the position of the contact block 77B. Become. Therefore, the substrate G is reliably and reliably transferred from the trolley side to the film forming unit side.

After the plasma CVD film is formed on the substrate G in the film forming chamber 18, the reverse operation is performed to transfer the substrate G from the film forming unit side to the trolley side. In this way, the substrate G
Is completed at timing t5.

Further, the controller 80 sends a signal to the gate valve mechanism 12 and the motor 70B at the timing t6 after the completion of the film formation / transfer of the substrate to open the gate valve, and at the same time, as shown in FIGS. As shown, the motor 70B is reversely rotated at the steady torque −T1 / steady speed −V1, and the carriage 6 is withdrawn from the film forming chamber 18 to the carriage rotation chamber 16.

Although the traveling control of the transfer carriage in the film forming chamber has been described in the above embodiment, the present invention is also applied to the carriage rotating chamber, the load chamber, the unload chamber, and the intermediate chamber other than the film forming chamber in the vacuum processing chamber. can do.

[0047]

As described above in detail, according to the present invention, it is possible to appropriately deal with a mechanical backlash at the bogie stop position at the substrate transfer place, and the substrate transfer operation. Is safe and reliable, and there is no risk of damaging the substrate due to collision or dropping with other members.

Further, according to the present invention, the same result is obtained when the same operation is repeated even when the stop position of the carriage is required to have high positional accuracy with respect to the target stop position (passing position). It is possible to guarantee the reproducibility of delivery.

Further, according to the present invention, it is not necessary to confirm the target stop position of the carriage every time the apparatus is maintained, and the cost and time required for the maintenance are reduced accordingly.

[Brief description of drawings]

FIG. 1 is a perspective plan view showing a vacuum processing system including a carrier.

FIG. 2 is a perspective view showing a gate valve and a carriage transport path provided in the vacuum processing system.

FIG. 3 is a perspective side sectional view showing a carriage and a drive mechanism in a vacuum processing chamber.

FIG. 4 is a perspective plan view showing a carriage and a drive mechanism in a vacuum processing chamber.

FIG. 5 is a partially enlarged cross-sectional view showing a drive mechanism and rails of a truck.

6A is a timing chart showing a drive torque (carrying force) control of a servo motor, FIG. 6B is a timing chart showing a rotation speed (carrying speed) control of the servo motor, and FIG. A timing chart showing delivery.

FIG. 7 is a diagram showing an outline of an apparatus used for conventional vehicle traveling control.

[Explanation of symbols]

6 ... carrier truck, 8 ... rail, 10 ... load room, 12 ... Gate valve mechanism, 16 ... Cart rotation room (common transfer room), 18 ... a film forming chamber, 19 ... Intermediate room (communication room) 20 ... Unload room, 61 ... body frame, 62 ... stanchions, 64 ... rack, 70A, 70B ... Servo motor, 72 ... Pinion, 75 ... encoder, 77A, 77B ... stop block, 78 ... Lifting cylinder mechanism, 80 ... controller, G ... substrate.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shigekazu Ueno             1-1 Satinoura Town, Nagasaki City, Nagasaki Prefecture Mitsubishi Heavy Industries             Nagasaki Shipyard Co., Ltd. (72) Inventor Eishiro Sasakawa             1-1 Satinoura Town, Nagasaki City, Nagasaki Prefecture Mitsubishi Heavy Industries             Nagasaki Shipyard Co., Ltd. F-term (reference) 4K030 CA06 CA12 GA12 JA03 JA12                       KA39 KA41                 5F031 CA05 FA02 FA07 FA12 FA18                       GA54 GA59 JA01 JA21 JA45                       LA08 LA14 MA28 MA29 MA32                       NA05 NA09

Claims (10)

[Claims] 1. A plurality of pinions, which are arranged at predetermined intervals along a rail, are engaged with a rack of a carrier truck to transmit a driving force, and a substrate held by the carrier truck is subjected to a plurality of vacuum treatments. In a vacuum chamber traveling control method for a transfer carriage that conveys a substrate to a chamber, (a) an abutment block is provided at a position where the transfer carriage cannot advance from a target stop position where a substrate is transferred from the transfer carriage to another member in the vacuum processing chamber. And (b) setting a distance that has a margin to reduce the propulsive force of the carrier until the carrier hits the stopper block, and (c) the number of rotations of the pinion or the pinion drive source. The number of revolutions is detected, and the position of the carrier is calculated based on the detected number of revolutions. (D) Whether the distance from the calculated position to the target stop position is the same as the distance set in step (b) or Yo When it also becomes smaller, the driving torque of the pinion is reduced to reduce the propulsive force of the carrier vehicle, and (e) the carrier vehicle is struck against the stopper block with a smaller propulsive force than during normal transfer, The driving of the transport carriage in the vacuum chamber is continued by driving the pinion with a low torque for a period of time, and continuously moving the transport carriage in a state of abutting against the stopper block. 2. The set distance in the step (b) is 90 to 11
The method according to claim 1, wherein the length is 0 mm. 3. The virtual travel distance that the transport vehicle would have advanced while assuming that there is no corresponding stop block while the transport vehicle is abutting against the stopper block in the step (e) is 100 to 300 mm. The method according to claim 1, characterized in that 4. The method according to claim 1, wherein in the step (d), the rotation speed of the pinion drive source is reduced to decelerate the carriage. 5. The method according to claim 1, wherein the predetermined time in the step (e) is a time until the transfer of the substrate from the carrier to another member is completed. 6. Further, after completing the transfer of the substrate in the step (e), the pinion is reversely rotated,
The method according to claim 5, wherein the transport carriage is evacuated from the vacuum processing chamber. 7. The method according to claim 1, wherein an AC servomotor is used as the pinion drive source. 8. The vacuum processing chamber comprises a plasma CV on a substrate.
The method according to claim 1, wherein the method is a film forming chamber for D film formation. 9. The method according to claim 1, wherein the vacuum processing chamber is a carriage rotation chamber that rotates a carriage to change a substrate transport direction. 10. The vacuum processing chamber is a load chamber in which a carrier truck enters from the atmosphere side to the vacuum side, or an unload chamber in which the carrier truck exits from the vacuum side to the atmosphere side. The method described.