Copper pad structure

Abstract

A structure (and method) for a metallurgical structure includes a passivation layer, a via through the passivation layer extending to a metal line within the metallurgical structure, a barrier layer lining the via, a metal plug in the via above the barrier layer, the metal plug and the metal line comprising a same material, and a solder bump formed on the metal plug.

What is claimed is:  
     
         1 . A metallurgical structure comprising: 
 a passivation layer;    a via through said passivation layer extending to a metal line within said metallurgical structure;    a barrier layer lining said via;    a metal plug in said via above said barrier layer, said metal plug and said metal line comprising a same material; and    a solder bump formed on said metal plug.    
     
     
         2 . The metallurgical structure in    claim 1   , wherein said same material comprises copper.  
     
     
         3 . The metallurgical structure in    claim 1   , wherein said barrier layer comprises one or more layers of Ti, TiN, Ta, and TaN.  
     
     
         4 . The metallurgical structure in    claim 1   , wherein said barrier layer and said metal plug prevent elements within said solder bump from diffusing to said metal line.  
     
     
         5 . The metallurgical structure in    claim 1   , wherein said metal plug, said barrier layer and said passivation layer form a planar exterior surface of said metallurgical structure.  
     
     
         6 . The metallurgical structure in    claim 1   , wherein said solder ball is in direct contact with said metal plug.  
     
     
         7 . The metallurgical structure in    claim 1   , further comprising a second barrier layer above said metal plug and a second metal plug above said second barrier layer, said second metal plug being in direct contact with said solder ball.  
     
     
         8 . An integrated circuit structure comprising: 
 internal components within an exterior covering;    a via extending through said exterior covering to said internal components;    a barrier layer lining said via;    a plug in said via above said barrier layer, said plug and said internal components comprising a same material; and    a connector formed on said plug.    
     
     
         9 . The integrated circuit structure in    claim 8   , wherein said same material comprises copper.  
     
     
         10 . The integrated circuit structure in    claim 8   , wherein said barrier layer comprises one or more layers of Ti, TiN, Ta, and TaN.  
     
     
         11 . The integrated circuit structure in    claim 8   , wherein said barrier layer and said plug prevent elements within said connector from diffusing to said components.  
     
     
         12 . The integrated circuit structure in    claim 8   , said plug, said barrier layer and said exterior covering form a planar exterior surface of said integrated circuit structure.  
     
     
         13 . The integrated circuit structure in    claim 8   , wherein said connector is in direct contact with said plug.  
     
     
         14 . The integrated circuit structure in    claim 8   , further comprising a second barrier layer above said plug and a second plug above said second barrier layer, said second plug being in direct contact with said connector.  
     
     
         15 . A method of forming an integrated circuit structure comprising: 
 forming a via through an exterior of said integrated circuit structure to internal components of said integrated circuit structure;    lining said via with a barrier layer;    forming a plug above said barrier layer, said plug and said internal components comprising a same material; and    forming a connector on said plug.    
     
     
         16 . The method in    claim 15   , wherein said same material comprises copper.  
     
     
         17 . The method in    claim 15   , wherein said barrier layer comprises one or more layers of Ti, TiN, Ta, and TaN.  
     
     
         18 . The method in    claim 15   , wherein said barrier layer prevents elements within said connector from diffusing to said internal components.  
     
     
         19 . The method in    claim 15   , further comprising polishing said integrated circuit structure such that said plug, said barrier layer and said exterior form a planar surface.  
     
     
         20 . The method in    claim 15   , wherein said connector is formed to be in direct contact with said plug.  
     
     
         21 . The method in    claim 15   , further comprising forming a second barrier layer above said plug and forming a second plug above said second barrier layer, such that said second plug is in direct contact with said connector.