Method for applying metal features onto metallized layers using electrochemical deposition and alloy treatment

Abstract

The present invention is directed to a process for producing structures containing metallized features for use in microelectronic workpieces. The process treats a barrier layer to promote the adhesion between the barrier layer and the metallized feature. Suitable means for promoting adhesion between barrier layers and metallized features according to the invention include an acid treatment of the barrier layer, an electrolytic treatment of the barrier layer, or deposition of a bonding layer between the barrier layer and metallized feature. The present invention thus modifies an exterior surface of a barrier layer making it more suitable for electrodeposition of metal on a barrier, thus eliminating the need for a PVD or CVD seed layer deposition process.

1 . A method for forming a metallized feature on a surface of a microelectronic workpiece, comprising steps of: 
 providing a workpiece having a barrier layer;    electrochemically depositing a metal alloy onto the barrier layer; and    electrochemically forming a metallized feature on the deposited metal alloy.    
   
   
       2 . The method of  claim 1 , wherein the metal alloy is a copper alloy.  
   
   
       3 . The method of  claim 1 , wherein the metal alloy includes copper as a first metal and a second metal selected from the group consisting of chromium, nickel, cobalt, zinc, aluminum, boron, magnesium, and cerium.  
   
   
       4 . The method of  claim 1 , wherein the composition of the metal alloy is constant throughout its thickness.  
   
   
       5 . The method of  claim 1 , wherein the composition of the metal alloy varies throughout its thickness.  
   
   
       6 . The method of  claim 3 , wherein the metal alloy supplements barrier properties of the barrier layer.  
   
   
       7 . The method of  claim 3 , wherein the alloy increases adhesion between the barrier layer and the metallized feature.  
   
   
       8 . A method for forming a copper feature on a surface of a microelectronic workpiece, comprising steps of: 
 providing a workpiece having a barrier layer;    electrochemically depositing a metal alloy onto the barrier layer; and    electrochemically forming a copper feature on the deposited metal alloy.    
   
   
       9 . The method of  claim 8 , wherein the metal alloy is a copper alloy.  
   
   
       10 . The method of  claim 8 , wherein the metal alloy includes copper as a first metal and a second metal selected from the group consisting of chromium, nickel, cobalt, zinc, aluminum, boron, magnesium, and cerium.  
   
   
       11 . The method of  claim 8 , wherein the composition of the metal alloy is constant throughout its thickness.  
   
   
       12 . The method of  claim 8 , wherein the composition of the metal alloy varies throughout its thickness.  
   
   
       13 . The method of  claim 10 , wherein the metal alloy supplements barrier properties of the barrier layer.  
   
   
       14 . The method of  claim 10 , wherein the metal alloy increases adhesion between the barrier layer and the metallized feature.