Method for applying metal features onto metallized layers using electrochemical deposition

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: 
 providing a workpiece having a metallized layer;    subjecting the metallized layer to a surface treatment to modify the surface of the metallized layer in a way that promotes adhesion between the surface treated metallized layer and a metallized feature to be formed on the surface treated metallized layer; and    electrochemically forming the metallized feature on the surface treated metallized layer.    
   
   
       2 . The method of  claim 1 , wherein the metallized layer is a barrier layer.  
   
   
       3 . The method of  claim 2 , wherein the step of electrochemically forming a metallized feature on the surface treated metallized layer comprises electrochemically depositing copper on the surface treated metallized layer.  
   
   
       4 . The method of  claim 1 , wherein the metallized feature comprises ruthenium.  
   
   
       5 . The method of  claim 4 , wherein the step of electrochemically forming a metallized feature on the surface treated metallized layer comprises electrochemically depositing copper on the surface treated metallized layer.  
   
   
       6 . The method of  claim 1 , wherein the surface treatment step comprises contacting a surface of the metallized feature with an inorganic acid solution feature with an inorganic acid solution in the absence of electroplating power to form an inorganic acid treated surface layer, the inorganic acid content of the inorganic acid solution being less than about 5 weight percent.  
   
   
       7 . The method of  claim 1 , wherein the surface treatment step comprises applying electrical power to the surface of a metallized layer and an electrode in contact with an electrolyte solution in contact with the surface of the metallized layer to produce an electrolytically treated surface of the metallized layer without depositing metal onto the metallized layer.  
   
   
       8 . The method of  claim 1 , wherein the surface treatment step comprises electrochemically depositing a metal alloy onto the metallized layer.