Method and apparatus for substrate transfer and processing

Abstract

The present invention allows large glass substrates to be rapidly moved from one processing station to another. Such movement occurs such that drives in different chambers are synchronized to move the glass substrates on shuttles at appropriate times. In systems according to the invention, at least a first and second chamber are provided. Typically, the first chamber is a load lock and the second chamber is a processing chamber. A substrate transfer shuttle is used to move substrate along a guide path defined by, e.g., guide rollers. Drive mechanisms are employed for most chambers to drive the shuttle along associated portions of the path. A control system is provided which powers the drive mechanism for the first chamber to drive the substrate transfer shuttle from a first position toward a second position and through an intermediate position. At the intermediate position, the substrate transfer shuttle begins to engage and induce movement of the drive mechanism for the second chamber. The control system receives an input caused by the induced movement of the drive mechanism for the second chamber, this input indicative of the substrate transfer shuttle having moved a predetermined distance beyond the intermediate position. The input may then be used to synchronize movement of the substrate transfer shuttle from the first chamber to the second chamber. Such synchronization may include reducing power to the drive mechanism for the first chamber and/or powering the drive mechanism for the second chamber.

What is claimed is:  
     
         1 . An apparatus for processing a substrate, comprising: 
 a first chamber;    a second chamber in communication with the first chamber;    a substrate transfer shuttle moveable along a shuttle path between a first position in the first chamber and a second position in the second chamber to transfer a substrate between the first chamber and the second chamber;    a drive mechanism between the first and second chambers configured to move the substrate transfer shuttle along an associated portion of a shuttle path:    a control system to control the drive mechanism and configured to power the drive mechanism to drive the substrate transfer shuttle from the first position to the second position.    
     
     
         2 . The apparatus of    claim 1   , wherein the first chamber is a load lock and the second chamber is a processing chamber.  
     
     
         3 . The apparatus of    claim 1   , wherein the drive mechanism farther comprises a pinion gear and a motor.  
     
     
         4 . An apparatus for processing a substrate, comprising: 
 a first chamber;    a second chamber in communication with the first chamber;    a third chamber in communication with the second chamber;    a substrate transfer shuttle moveable along a shuttle path between a first position in the first chamber, a second position in the second chamber, and a third position in the third chamber, to transfer a substrate between the chambers;    a drive mechanism for the first and second chambers configured to move the substrate transfer shuttle along an associated portion of the shuttle path:    a control system to control each drive mechanism and configured to: 
 power the drive mechanism for the first chamber to drive the substrate transfer shuttle from the first position toward the third position and through an intermediate position wherein the substrate transfer shuttle begins to engage and be driven by the drive mechanism for the second chamber; and  
 receive an input indicative of the substrate transfer shuttle having passed through the intermediate position,  
   whereby transfer of the substrate transfer shuttle is synchronized from the drive mechanism for the first chamber to the drive mechanism for the second chamber.    
     
     
         5 . The apparatus of    claim 4   , wherein the control system is further configured to, upon powering of the drive mechanism for the first chamber, power the drive mechanism for the second chamber.  
     
     
         6 . The apparatus of    claim 4   , wherein the control system is further configured to, after powering of the drive mechanism for the first chamber, and before contact of the shuttle and the drive mechanism for the second chamber, power the drive mechanism for the second chamber.  
     
     
         7 . The apparatus of    claim 4   , wherein the control system is further configured to, upon receiving said input, power the drive mechanism for the second chamber.  
     
     
         8 . The apparatus of    claim 5   , wherein the control system is further configured to: 
 upon receiving said input, reduce power to the drive mechanism for the first chamber.    
     
     
         9 . The apparatus of    claim 4   , wherein the control system includes an encoder coupled to a motor to determine an amount of movement caused by the motor.  
     
     
         10 . The apparatus of    claim 4   , wherein each drive mechanism further includes pinion gears and said substrate transfer shuttle further includes a toothed rack, wherein said pinion gears are meshable with said toothed rack.  
     
     
         11 . An apparatus for processing a substrate, comprising: 
 a first chamber;    a second chamber in communication with the first chamber;    a third chamber in communication with the second chamber;    a first substrate transfer shuttle moveable along a shuttle path between a first position in the first chamber and a second position in the second chamber for transferring a substrate between the first chamber and the second chamber;    a second substrate transfer shuttle moveable along a shuttle path between a third position in the third chamber and the second position in the second chamber for transferring a substrate between the third chamber and the second chamber;    a drive mechanism for each of the first, second, and third chambers configured to move the substrate transfer shuttles along associated portions of the shuttle paths; and    a control system to control each drive mechanism.    
     
     
         12 . The apparatus of    claim 11   , wherein said control system is configured and arranged such that movements of said first and second substrate transfer shuttles are controlled independently of each other.  
     
     
         13 . The apparatus of    claim 11   , wherein said first and third chambers are load locks, and said second chamber is a processing chamber.  
     
     
         14 . The apparatus of    claim 11   , wherein the control system is configured and arranged such that movements of said first and second substrate transfer shuttles may be effected simultaneously.  
     
     
         15 . The apparatus of    claim 11   , wherein said control system is configured and arranged such that movements of said first and second substrate transfer shuttles are coordinated.  
     
     
         16 . An apparatus for processing a substrate, comprising: 
 a first chamber;    a second chamber in communication with the first chamber, the second chamber configured to perform a process on the substrate in a target position within the second chamber;    a substrate transfer shuttle for carrying the substrate, said substrate transfer shuttle having mounted thereon an element located at a predetermined location, said element capable of being sensed by a sensor, the substrate transfer shuttle moveable along a shuttle path between the first chamber and the second chamber;    a sensor assembly in the second chamber located along the shuttle path and configured to detect when the element is at a predetermined distance from the target position; and    a control system for controlling movement of the substrate transfer shuttle along the shuttle path and configured to receive an input from the sensor assembly indicating the position of the substrate transfer shuttle, said sensor assembly output providing a feedback to the control system to correct for errors in positioning of the substrate transfer shuttle.    
     
     
         17 . The apparatus of    claim 16   , wherein said predetermined location is on a leading edge of the substrate transfer shuttle.  
     
     
         18 . The apparatus of    claim 17   , further including: 
 an optical sensor in the second chamber located along the shuttle path and configured to detect the leading edge of the substrate; and    wherein the control system is configured and arranged to use a feedback from the optical sensor and the input from the sensor assembly to control movement of the substrate transfer shuttle and to correct for errors in positioning of the substrate transfer shuttle.    
     
     
         19 . The apparatus of    claim 18   , wherein said optical sensor is a photodetector.  
     
     
         20 . The apparatus of    claim 18   , further comprising a laser for providing incident light to detect the leading edge of the substrate.  
     
     
         21 . The apparatus of    claim 16   , wherein said sensor assembly includes two sensors to determine when said element is located equidistant from each sensor.  
     
     
         22 . The apparatus of    claim 21   , wherein said element is a magnet and said sensors are magnetic sensors.  
     
     
         23 . The apparatus of    claim 21   , wherein said magnetic sensors are Hall effect sensors.  
     
     
         24 . An apparatus for processing a substrate, said substrate having a leading edge relative to a direction of motion, comprising: 
 a first chamber;    a second chamber in communication with the first chamber, the second chamber configured to perform a process on the substrate in a target position within the second chamber, and including a lift mechanism for supporting the substrate at the target position;    a substrate transfer shuttle for carrying the substrate at a substrate-carrying location defined on said substrate transfer shuttle, said substrate transfer shuttle having a forward edge spaced a predetermined distance away from the substrate-carrying location and moveable along a shuttle path between the first chamber and the second chamber, the substrate transfer shuttle configured and arranged so that when in the target position the substrate may be exchanged between the substrate transfer shuttle and the lift mechanism;    a sensor in the second chamber located along the shuttle path and configured to detect when the forward edge of the substrate transfer shuttle or the leading edge of the substrate reaches an intermediate location separated from the target position by said predetermined distance; and    a control system for controlling movement of the substrate transfer shuttle along the shuttle path and configured to receive an input from the sensor indicating that the forward edge of the substrate transfer shuttle or the leading edge of the substrate has reached the intermediate location and terminating movement of the substrate transfer shuttle when the substrate transfer shuttle moves the predetermined distance beyond the intermediate location.    
     
     
         25 . The apparatus of    claim 24   , wherein said sensor is a magnetic field sensor.  
     
     
         26 . The apparatus of    claim 24   , further including at least one limit sensor located within at least one of said first and second chambers near said shuttle path to provide a signal to said control system to terminate movement of the substrate transfer shuttle when the substrate transfer shuttle reaches a predetermined limit location.  
     
     
         27 . The apparatus of    claim 26   , wherein said predetermined location is a predefined distance away from a hard stop location.  
     
     
         28 . The apparatus of    claim 24   , wherein said sensor is an optical sensor.  
     
     
         29 . The apparatus of    claim 28   , wherein said optical sensor is a laser.  
     
     
         30 . The apparatus of    claim 28   , wherein said optical sensor includes a photodetector and a photosensor.  
     
     
         31 . The apparatus of    claim 30   , wherein said substrate transfer shuttle has a toothed rack on an underside thereof and is supported by a plurality of guide rollers located along a perimeter of the first and second chambers, and wherein each drive mechanism has a motor and a pinion gear, said pinion gear capable of being mechanically coupled to said toothed rack to move said substrate transfer shuttle.  
     
     
         32 . An apparatus for processing a substrate, comprising: 
 a plurality of chambers;    two substrate transfer shuttles moveable along a shuttle path between said plurality of chambers, the substrate transfer shuttles to transfer substrates between one and another of said plurality of chambers;    a drive mechanism for at least some of the plurality of chambers, the drive mechanisms configured to move the substrate transfer shuttles along associated portions of the shuttle path; and    a control system to control each drive mechanism, the control system coordinating movements of the substrate transfer shuttles.    
     
     
         33 . The apparatus of    claim 32   , wherein the control system is further configured to move each substrate transfer shuttle simultaneously.  
     
     
         34 . A method of placing a substrate on a substrate-carrying element in a target position in a processing chamber, comprising steps of: 
 providing a substrate-carrying element movable into and out of a processing chamber along a path extending through target position;    providing a sensor at a sensor location adjacent the path, the sensor location selected to have a substantially temperature-invariant alignment with the target position;    moving the substrate-carrying element in a direction along the element path;    providing a trigger on the substrate-carrying element;    receiving an input signal from the sensor responsive to the trigger being sensed by the sensor as the substrate-carrying element reaches the sensor location as it is moved; and    responsive to receiving the input signal, terminating movement of the substrate-carrying element after the substrate-carrying element has moved a predetermined distance past the sensor location.    
     
     
         35 . A method of placing a substrate-carrying element in a substrate target position in a processing chamber, comprising: 
 moving the substrate-carrying element into the processing chamber along a path;    detecting when an element at a predetermined position on said substrate-carrying element is at a predetermined relationship with respect to said substrate target position, said detecting performed using a sensor located along the path at a sensor location at which its measurements are not adversely affected by the temperature within the processing chamber; and    stopping movement of the substrate-carrying element upon said detection.    
     
     
         36 . The method of    claim 35   , wherein said predetermined relationship is a minimum distance.  
     
     
         37 . A method of placing a substrate-carrying element in a substrate target position in a processing chamber, comprising: 
 moving the substrate-carrying element into the processing chamber along a path;    detecting when a predetermined portion on said substrate-carrying element is at a predetermined distance from said substrate target position, using a sensor located along the path at a location at which its measurements are not adversely affected by the temperature within the processing chamber; and    controlling movement of the substrate-carrying element upon said detection such that said substrate is controllably moved to said substrate target position.    
     
     
         38 . The method of    claim 37   , wherein said predetermined distance is a minimum distance.  
     
     
         39 . A method of placing a substrate-carrying element in a substrate target position in a processing chamber, comprising: 
 moving the substrate-carrying element into the processing chamber along a path extending through an intermediate position located at a predetermined distance from the target position, the substrate-carrying element having a leading edge portion separated from a substrate-carrying location on the substrate-carrying element at a distance equal to the predetermined distance;    detecting when the leading edge portion reaches the intermediate position using a sensor located along the path at a sensor location at which its measurements are not adversely affected by the temperature within the processing chamber; and    stopping movement of the substrate-carrying element after it moves the predetermined distance beyond the intermediate position.    
     
     
         40 . The method of    claim 39   , wherein said movement for said predetermined distance is determined by an encoder.  
     
     
         41 . The method of    claim 39   , wherein said stopping is accomplished by reducing power to a drive mechanism driving said substrate-carrying element.  
     
     
         42 . The method of    claim 39   , further including: 
 moving a second substrate-carrying element having a lead edge portion along the element path;    detecting when a leading edge portion of the second substrate-carrying element reaches the intermediate position; and    stopping movement of the second substrate-carrying element after it moves a predetermined distance beyond the intermediate position.    
     
     
         43 . The method of    claim 39   , wherein said first and second substrate-carrying elements are moveable in opposite directions.  
     
     
         44 . The method of    claim 39   , wherein the sensor location is near a center plane of the processing chamber, the center plane being perpendicular to the path.  
     
     
         45 . The method of    claim 39   , wherein said sensor is a photodetector.  
     
     
         46 . The method of    claim 39   , wherein said sensor is a laser.  
     
     
         47 . The method of    claim 39   , wherein said sensor is a magnetic sensor and said leading edge portion further comprises a magnetic element mounted thereon.  
     
     
         48 . A method for processing a substrate, comprising: 
 moving a substrate transfer shuttle along a shuttle path between a first position in a first chamber and a second position in a second chamber to transfer a substrate between the first chamber and the second chamber;    controlling a drive mechanism for the chambers to move the substrate transfer shuttle along an associated portion of the shuttle path, wherein said controlling includes:    powering the drive mechanism to drive the substrate transfer shuttle from the first position toward the second position; 
 receiving an input indicative of the substrate transfer shuttle having reached the second position; and  
 reducing or eliminating power to the drive mechanism.  
   
     
     
         49 . A method of controlling movement of a substrate-carrying element in a processing chamber, comprising: 
 moving the substrate-carrying element along a path in a processing chamber, said path extending through a predetermined location, the substrate-carrying element having a leading edge portion;    detecting when the leading edge portion reaches the predetermined location using a sensor; and    stopping movement of the substrate-carrying element when said leading edge portion reaches the predetermined location.    
     
     
         50 . A method of controlling movement of a substrate-carrying element in a processing chamber, comprising: 
 moving the substrate-carrying element along a path in a processing chamber, said path extending through a predetermined location located at a predetermined distance from a drive mechanism, the substrate-carrying element having a leading edge portion;    detecting when the leading edge portion reaches the predetermined location using a sensor; and    stopping movement of the substrate-carrying element when said leading edge portion reaches the predetermined location, whereby a mechanical coupling of said substrate-carrying element and said drive mechanism is maintained.    
     
     
         51 . A method for processing a substrate, comprising: 
 moving a substrate transfer shuttle along a shuttle path between a first position in a first chamber and through a second position in a second chamber and to a third position in a third chamber to transfer a substrate between the first chamber and the third chamber;    controlling a drive mechanism for each of the first, second, and third chambers to move the substrate transfer shuttle along associated portions of the shuttle path, wherein said controlling includes: 
 powering the drive mechanism for the first chamber to drive the substrate transfer shuttle from the first position toward the third position and through an intermediate position wherein the substrate transfer shuttle begins to engage and be driven by the drive mechanism for the second chamber;  
 receiving an input indicative of the substrate transfer shuttle having passed through the intermediate position;  
 powering the drive mechanism for the second chamber to drive the substrate transfer shuttle from the intermediate position toward the third position.  
   
     
     
         52 . The method of    claim 51   , wherein said controlling further includes, upon powering of the drive mechanism for the first chamber, powering the drive mechanism for the second chamber.  
     
     
         53 . The method of    claim 51   , wherein said controlling further includes, after powering of the drive mechanism for the first chamber, and before contact of the shuttle and the drive mechanism for the second chamber, powering the drive mechanism for the second chamber.  
     
     
         54 . The method of    claim 45   , wherein said controlling further includes, after powering of the drive mechanism for the first chamber, upon contact of the shuttle and the drive mechanism for the second chamber, powering the drive mechanism for the second chamber.  
     
     
         55 . A method for processing a substrate, comprising: 
 moving a first substrate transfer shuttle along a shuttle path between a first position in a first chamber and one of a second position in a second chamber or a third position in a third chamber to transfer a substrate between the first, second, and third chambers;    moving a second substrate transfer shuttle along a shuttle path between a fourth position in a fourth chamber and one of the second position in the second chamber or the third position in the third chamber to transfer a substrate between the second, third, and fourth chambers;    controlling a drive mechanism for each of the first, second, and third chambers to move the substrate transfer shuttle along associated portions of the shuttle path.    
     
     
         56 . The method of    claim 55   , wherein said first and second substrate transfer shuttles are controlled independently.  
     
     
         57 . The method of    claim 55   , wherein said first and second substrate transfer shuttles are controlled in a coordinated manner.  
     
     
         58 . The method of    claim 55   , wherein said first and second substrate transfer shuttles move simultaneously.  
     
     
         59 . A method for processing a substrate, comprising: 
 moving a first substrate transfer shuttle along a shuttle path between a first position in a first chamber and a second position in a second chamber to transfer a substrate between the first and second chambers;    moving a second substrate transfer shuttle along a shuttle path between a third position in a third chamber and the second position in the second chamber to transfer a substrate between the second and third chambers;    controlling a drive mechanism for each of the first, and second chambers to move the substrate transfer shuttle along associated portions of the shuttle path.