Distributing forces for electrodeposition

Abstract

The force required to seal a surface of an object for electrodeposition may be controlled. For example, the object may rest on a support that carries the majority of the force required for surface sealing. Further, pads mounted on the ends of flexible beams may exert a variable force to establish electrical contact with the object that may be controlled. By controlling the forces exerted on an object damage to the object's surface may be minimized or eliminated.

1 . A device comprising: 
 more than one spring electrical contact to contact a first surface of an object, said first surface of said object to have a material electrodeposited thereon; and    a base to directly support said first surface of said object without being directly connected to said spring electrical contacts, said base to distribute the force to seal a second surface of said object.    
     
     
         2 . The device of  claim 1  including a soft, acid resistant material disposed on said base.  
     
     
         3 . The device of  claim 1  wherein said base is spaced inward from said contacts.  
     
     
         4 . The device of  claim 1  wherein said spring electrical contacts are connected to a frame.  
     
     
         5 . The device of  claim 4  wherein said spring electrical contacts are resilient beams that terminate with tips.  
     
     
         6 . The device of  claim 5  wherein said object has an outer edge, said base to distribute a force at said object outer edge and said tips to contact said object inward from said base.  
     
     
         7 . The device of  claim 4  wherein said base and said frame are annular.  
     
     
         8 . The device of  claim 4  wherein said frame and said beams are coated with an acid-resistant material.  
     
     
         9 . The device of  claim 1  wherein said base substantially continuously contacts said surface.  
     
     
         10 . The device of  claim 1  wherein said spring electrical contacts independently deflect while electrical contact is made with said object.  
     
     
         11 . A system comprising: 
 a frame having spring electrical contacts to electrically contact a first surface of an object to enable electrodeposition on said object first surface;    a base to directly support said object, said base and said frame not directly connected; and    a sealing ring to seal a second surface of said object to prepare for electrodeposition.    
     
     
         12 . The system of  claim 11  including a plating cell to house said object for electroplating.  
     
     
         13 . The system of  claim 12  including an electrode.  
     
     
         14 . The system of  claim 13  including a power supply.  
     
     
         15 . The system of  claim 14  including a thrust plate and a seal plate.  
     
     
         16 . The system of  claim 11  wherein said base is annular defining an annular aperture.  
     
     
         17 . The system of  claim 11  wherein said base is to distribute the force required to seal said second surface of said object.  
     
     
         18 . The system of  claim 11  wherein said object is a wafer and a metal or metal alloy is to be deposited on said first surface.  
     
     
         19 . The system of  claim 11  wherein said object is a wafer and copper or an alloy including copper is to be deposited on said first surface.  
     
     
         20 . The system of  claim 11  wherein said spring electrical contacts apply a variable force less than the force that if applied would exceed the mechanical strength of said object.  
     
     
         21 . A method comprising: 
 sealing a second side of an object to prepare said object for electrodeposition;    directly physically supporting said object on a first side to enable said sealing; and    electrically contacting said first side of said object with spring electrical contacts to facilitate electrodeposition, said electrical spring contacts and said support not in direct contact.    
     
     
         22 . The method of  claim 21  including distributing the force to seal said second side of said object about the periphery of said object.  
     
     
         23 . The method of  claim 21  including applying a variable force with said spring electrical contacts to facilitate electrodeposition.  
     
     
         24 . The method of  claim 23  including determining the length and the maximum displacement of said spring electrical contacts.  
     
     
         25 . The method of  claim 21  including distributing the force to seal said second side of said object without exceeding the strength of said object first side.  
     
     
         26 . The method of  claim 21  including depositing a conductive material on said object first side.  
     
     
         27 . The method of  claim 26  including depositing a metal or metal alloy on said object first side.  
     
     
         28 . The method of  claim 21  including displacing adjacent spring electrical contacts with respect to said object first side.  
     
     
         29 . The method of  claim 21  including initially contacting said object with said spring electrical contacts, said initial contact having little or no associated force.  
     
     
         30 . The method of  claim 21  including electrically contacting said first side of said object without exceeding the strength of said object first side.