Compact apparatus and method for storing and loading semiconductor wafer carriers

Abstract

An improved apparatus and method is provided for storing semiconductor wafer carriers, and for loading wafers or wafer carriers to a fabrication tool. The apparatus preferably provides an elevated port for receipt of wafer carriers from an overhead factory transport, allows for local interconnection among a plurality of the inventive apparatuses, and enables independent loading of the factory load port and the tool load port. An inventive wafer handling method which divides a lot of wafers into sublots and distributes the sublots among tools configured to perform the same process is also provided.

What is claimed is:  
     
         1 . A method of providing wafers to a fabrication tool having a wafer exchange port coupled thereto for transferring one or more wafers from a wafer carrier to the fabrication tool, comprising: 
 unloading a wafer carrier from an overhead wafer carrier transport system via a wafer carrier transfer mechanism;    lowering the wafer carrier via the wafer carrier transfer mechanism, to the wafer exchange port;    placing the wafer carrier on the wafer exchange port;    opening the wafer carrier; and    extracting at least one wafer from the wafer carrier    
     
     
         2 . The method of  claim 1  further comprising: 
 placing the wafer carrier on a storage shelf after unloading from the overhead wafer carrier transport system, and before placing the wafer carrier on the wafer exchange port.  
 
     
     
         3 . A system comprising: 
 a fabrication tool comprising a processing chamber for performing a process on at least one wafer;    an overhead wafer carrier transport system;    a wafer exchange port adapted to open a wafer carrier such that at least one wafer can be extracted therefrom for loading to the fabrication tool; and    a wafer handler comprising an end effector and at least one vertical guide that extends between the overhead wafer carrier transport system and the wafer exchange port so that the end effector may transfer a wafer carrier therebetween.    
     
     
         4 . The system of  claim 3  further comprising a fabrication tool comprising a processing chamber for performing a process on the at least one wafer.  
     
     
         5 . The system of  claim 4  wherein the fabrication tool further comprises a load lock for receiving the at least one wafer from the wafer exchange port.  
     
     
         6 . The system of  claim 3  further comprising a storage location located between the overhead wafer carrier transport system and the wafer exchange port, such that the wafer handler may transfer a wafer carrier thereamong.  
     
     
         7 . The system of  claim 3  wherein the overhead wafer carrier transport system comprises a monorail.  
     
     
         8 . An apparatus for supplying at least one wafer to a fabrication tool, comprising: 
 a wafer exchange port coupled to a fabrication tool;    an overhead load port comprising a location to which a wafer carrier is transported via an overhead wafer carrier transport system;    a storage location located at an elevation above the elevation of the wafer exchange port coupled to the fabrication tool; and    a vertical transfer mechanism adapted to transfer a wafer carrier between the overhead load port and the storage location.    
     
     
         9 . The apparatus of  claim 8  wherein the overhead load port comprises a location along the overhead wafer carrier transport system.  
     
     
         10 . The apparatus of  claim 7  wherein the overhead wafer carrier transport system comprises a monorail.