Clean method and apparatus for vacuum holding of substrates

Abstract

A system for preventing contaminants and particulates from coming into contact with a back side of a workpiece as the workpiece is vacuum held on a chuck or robotic end effector.

I claim:  
     
         1 . A vacuum holding system for holding a workpiece on a support surface associated with a semiconductor process, comprising: 
 an evacuation channel formed in an upper surface of the support surface, the workpiece having a back side exposed to said evacuation channel;    a vacuum path in communication with said vacuum channel;    a filter in said vacuum path adjacent said evacuation channel for filtering a fluid flowing through said vacuum path and for impeding a flow of fluid through to and/or from the back side of the workpiece exposed to said evacuation channel.    
     
     
         2 . A vacuum holding system for holding a workpiece on a support surface associated with a semiconductor process as recited in  claim 1 , said support surface comprising at least a portion of an end effector.  
     
     
         3 . A vacuum holding system for holding a workpiece on a support surface associated with a semiconductor process as recited in  claim 1 , said support surface comprising at least a portion of a chuck associated with a semiconductor process.  
     
     
         4 . A vacuum holding system for holding a workpiece on a support surface associated with a semiconductor process as recited in  claim 1 , wherein said evacuation channel comprises a narrow annular channel adjacent edges of the support surface.  
     
     
         5 . A vacuum holding system for holding a workpiece on a support surface associated with a semiconductor process as recited in  claim 1 , wherein a source of fluid to said evacuation channel is filtered.  
     
     
         6 . A vacuum holding system for holding a workpiece on a support surface of a workpiece chuck associated with a semiconductor process, comprising: 
 an evacuation channel formed in an upper surface of the support surface, the workpiece having a back side exposed to said evacuation channel;    a vacuum path in communication with said vacuum channel;    a filter in said vacuum path spaced not greater than 3 inches from said support surface along said vacuum path for filtering a fluid flowing through said vacuum path and for impeding a flow of fluid through to and/or from the back side of the workpiece exposed to said evacuation channel.    
     
     
         7 . A vacuum holding system for holding a workpiece on a support surface of an end effector associated with a semiconductor process, comprising: 
 an evacuation channel formed in an upper surface of the support surface, the workpiece having a back side exposed to said evacuation channel;    a vacuum path in communication with said vacuum channel; a filter in said vacuum path spaced not greater than 12 inches from said support surface along said vacuum path for filtering a fluid flowing through said vacuum path and for impeding a flow of fluid through to and/or from the back side of the workpiece exposed to said evacuation channel.    
     
     
         8 . A vacuum holding system for holding a workpiece on a support surface of a workpiece chuck associated with a semiconductor process, the workpiece chuck supported on a shaft capable of rotation with respect to a base portion, comprising: 
 an evacuation channel formed in an upper surface of the support surface, the workpiece having a back side exposed to said evacuation channel;    a vacuum path though said shaft and in communication with said vacuum channel;    a filter in said vacuum path in the shaft for filtering a fluid flowing through said vacuum path and for impeding a flow of fluid through to and/or from the back side of the workpiece exposed to said evacuation channel.