Semiconductor substrate cleaning system

Abstract

A modular semiconductor substrate cleaning system is provided that processes vertically oriented semiconductor substrates. The system features a plurality of cleaning modules that may include a megasonic tank-type cleaner followed by a scrubber. An input module may receive a horizontally oriented substrate and rotate the substrate to a vertical orientation, and an output module may receive a vertically oriented substrate and rotate the substrate to a horizontal orientation. Each of the modules (input, cleaning and output) has a substrate support and may be positioned such that the substrate supports of adjacent modules are equally spaced. The modules are coupled by an overhead transfer mechanism having a plurality of substrate handlers spaced the same distance (X) as the substrate supports of the modules therebelow. The transfer mechanism indexes forward and backward the distance X to simultaneously transport semiconductor substrates through the cleaning system, lifting and lowering substrates from the desired modules wafer rotation/orientation sensors, an input module cart for transporting wafers between a substrate handler of a previous tool (such as a semiconductor substrate polisher) and a substrate handler of the cleaning system are also included.

The invention claimed is:  
     
         1 . A method of automatically cleaning a semiconductor substrate within a semiconductor substrate cleaning system comprising: 
 cleaning a first semiconductor substrate within a sonic cleaning tank while cleaning a second semiconductor substrate within a scrubber;    automatically transferring the first semiconductor substrate to the scrubber via an overhead transfer mechanism; and    automatically transferring the second semiconductor substrate from the scrubber via the overhead transfer mechanism.    
     
     
         2 . The method of  claim 1  further comprising: 
 receiving a semiconductor substrate in a horizontal orientation at an input module;  
 rotating the semiconductor substrate to a vertical orientation;  
 automatically transferring the vertically oriented substrate to the sonic cleaning tank via the overhead transfer mechanism for cleaning;  
 automatically transferring a semiconductor substrate in a vertical orientation to an output module after cleaning is complete; and  
 rotating the semiconductor substrate in the output module to a horizontal orientation;  
 wherein rotating within the input module, and rotating within the output module occur while semiconductor substrates are cleaned within the cleaning modules; and  
 wherein transferring semiconductor substrates from one module to another occurs simultaneously.  
 
     
     
         3 . The method of  claim 1  further comprising: 
 providing the sonic cleaning tank having a substrate support for supporting a single semiconductor substrate in a vertical orientation;  
 providing the scrubber having a substrate support for supporting a single semiconductor substrate in a vertical orientation;  
 coupling the tank and the scrubber so as to position the substrate supports thereof a predetermined distance apart; and  
 movably coupling the overhead transfer mechanism above the tank and the scrubber, wherein the overhead transfer mechanism comprises a plurality of substrate handlers positioned the predetermined distance apart.  
 
     
     
         4 . A wafer cleaning system comprising a cleaning module having a wafer support which defines a wafer plane which is approximately vertical, and a wafer handler having grippers which define a wafer plane which is approximately vertical, the wafer handler being adapted to transfer a wafer to and from the wafer cleaning module.  
     
     
         5 . A substrate cleaning system comprising: 
 a megasonic tank;    a scrubber; and    a transfer mechanism adapted to transfer a substrate between the megasonic tank and the scrubber.    
     
     
         6 . A method of cleaning a substrate comprising: 
 introducing a substrate into a cleaning system megasonically cleaning the substrate;    scrubbing the substrate; and    automatically transferring the substrate between the megasonic cleaning and scrubbing.    
     
     
         7 . A method of cleaning a substrate comprising: 
 supporting a substrate in a roughly vertical position within a first cleaning apparatus cleaning the substrate in the first cleaning apparatus,    transferring the substrate to a second cleaning apparatus; supporting the substrate in a roughly vertical position within the second cleaning apparatus; and    cleaning the substrate in the second apparatus.