Electroplating apparatus

Abstract

A electroplating apparatus which is suitable for depositing a metal layer of substantially uniform thickness across the center and edge regions of a semiconductor wafer substrate is disclosed. The apparatus includes a reservoir for containing an electrolytic fluid. A cathode, to which is mounted a wafer, and an anode in the electrolytic fluid are connected to an electroplating current source. A shield is provided between the cathode and anode to facilitate a more uniform deposit of the metal onto the wafer across the entire surface, including the center and edge regions, of the wafer.

1 . An electroplating apparatus comprising: 
 a reservoir for holding an electrolyte fluid;    an anode and a cathode for holding a wafer provided in said reservoir;    an electrical pathway provided between said cathode and said anode; and    a shield provided between said cathode and said anode.    
     
     
         2 . The electroplating apparatus of  claim 1  wherein said shield comprises a generally ring-shaped shield body.  
     
     
         3 . The electroplating apparatus of  claim 2  further comprising an electrically-conductive material provided on said shield body.  
     
     
         4 . The electroplating apparatus of  claim 3  wherein said electrically-conductive material comprises copper.  
     
     
         5 . The electroplating apparatus of  claim 3  further comprising a shield current source electrically connected to said shield for selectively applying a negative charge to said shield.  
     
     
         6 . The electroplating apparatus of  claim 2  wherein said shield body comprises an electrically non-conductive material.  
     
     
         7 . An electroplating apparatus comprising: 
 a reservoir for holding an electrolyte fluid;    an anode and a cathode for holding a wafer provided in said reservoir;    an electrical pathway provided between said cathode and said anode; and    a shield comprising a generally plate-shaped shield body provided between said cathode and said anode.    
     
     
         8 . The electroplating apparatus of  claim 7  further comprising an electrically-conductive material provided on said shield body.  
     
     
         9 . The electroplating apparatus of  claim 8  wherein said electrically-conductive material comprises copper.  
     
     
         10 . The electroplating apparatus of  claim 8  further comprising a shield current source electrically connected to said shield for selectively applying a negative charge to said shield.  
     
     
         11 . The electroplating apparatus of  claim 7  wherein said shield body comprises an electrically non-conductive material.  
     
     
         12 . A method of electroplating a metal on a wafer, comprising: 
 providing a reservoir containing an electrolyte fluid;    providing an anode and a cathode in said reservoir;    providing an electrical pathway between said cathode and said anode;    providing a shield in said electrolyte fluid between said cathode and said anode; and    applying a current to said cathode and said anode.    
     
     
         13 . The method of  claim 12  wherein said shield comprises a generally ring-shaped shield body.  
     
     
         14 . The method of  claim 13  further comprising an electrically-conductive material provided on said shield body.  
     
     
         15 . The method of  claim 14  wherein said electrically-conductive material comprises copper.  
     
     
         16 . The method of  claim 14  further comprising a shield current source electrically connected to said shield for selectively applying a negative charge to said shield.  
     
     
         17 . The method of  claim 16  further comprising selectively applying said negative charge to said shield for electroplating a metal onto said shield and applying a positive charge to said shield for releasing metal cations from said shield into said electrolyte fluid.  
     
     
         18 . The method of  claim 13  wherein said shield body comprises an electrically non-conductive material.  
     
     
         19 . The method of  claim 12  wherein said shield comprises a generally plate-shaped shield body.  
     
     
         20 . The method of  claim 19  further comprising an electrically-conductive material provided on said shield body.  
     
     
         21 . The method of  claim 20  wherein said electrically-conductive material comprises copper.  
     
     
         22 . The method of  claim 20  further comprising a shield current source electrically connected to said shield for selectively applying a negative charge to said shield.  
     
     
         23 . The method of  claim 19  wherein said shield body comprises an electrically non-conductive material.  
     
     
         24 . The method of  claim 22  further comprising selectively applying said negative charge to said shield for electroplating a metal onto said shield and applying a positive charge to said shield for releasing metal cations from said shield into said electrolyte fluid.