Method for Via Plating with Seed Layer

Abstract

Presented herein is a method for plating comprising providing a substrate having a dielectric layer formed over a trace, and forming a via/trench opening extending through the dielectric layer, the via/trench opening exposing a surface of the trace. The method further comprises forming a seed layer in the via/trench opening and contacting the trace and forming a protection layer over the seed layer. The protection layer is removed and a conductive layer deposited on the seed layer in a single plating process step by applying a plating solution in the via/trench opening.

What is claimed is: 
     
         1 . A method of forming a structure, the method comprising:
 etching an opening in a dielectric layer;   depositing a seed layer on the dielectric layer in the opening;   depositing a metallic protection layer over the seed layer; and   removing the metallic protection layer while forming a conductor in the opening, wherein the seed layer is protected from oxidation during the depositing the metallic protection layer, the removing the metallic protection layer, and the depositing the conductor.   
     
     
         2 . The method of  claim 1 , wherein removing the metallic protection layer and forming the conductor comprises exposing the metallic protection layer to an electroplating solution. 
     
     
         3 . The method of  claim 2 , wherein the electroplating solution comprises copper sulfate (CuSO 4 ) and sulfuric acid (H 2   50   4 ). 
     
     
         4 . The method of  claim 3 , wherein the electroplating solution comprises acid for removing the metallic protection layer. 
     
     
         5 . The method of  claim 3 , wherein the electroplating solution has an ionic copper (Cu+) concentration by weight between about 2.0% and about 3.7%. 
     
     
         6 . The method of  claim 3 , wherein a pH of the electroplating solution to about 6.0 or less. 
     
     
         7 . The method of  claim 1 , wherein the metallic protection layer has a thickness between about 1 Angstrom and about 50 Angstroms. 
     
     
         8 . The method of  claim 1 , wherein depositing the metallic protection layer is performed in an inert environment. 
     
     
         9 . A method of forming a structure, the method comprising:
 forming a seed layer on exposed surfaces of an opening in a dielectric layer;   forming a metallic protecting layer on the seed layer, wherein the seed layer and the metallic protecting layer are formed in an inert environment; and   forming a conductor in the opening using an electroplating solution, the electroplating solution comprising an agent for removing the metallic protecting layer during the forming the conductor in the opening.   
     
     
         10 . The method of  claim 9 , wherein the metallic protecting layer comprises manganese (Mn), cobalt (Co), Ti, Al, vanadium (V), chromium (Cr), zinc (Zn), or zirconium (Zr). 
     
     
         11 . The method of  claim 9 , wherein the agent for removing the metallic protecting layer comprises an acid. 
     
     
         12 . The method of  claim 9 , wherein the electroplating solution has an ionic copper (Cu+) concentration by weight between about 2.0% and about 3.7%. 
     
     
         13 . The method of  claim 9 , wherein the metallic protecting layer has a lower reduction-oxidation potential than the conductor. 
     
     
         14 . The method of  claim 9 , wherein the electroplating solution comprises copper sulfate (CuSO 4 ) and sulfuric acid (H 2 SO 4 ). 
     
     
         15 . The method of  claim 9 , wherein removing the metallic protecting layer comprises submerging the metallic protecting layer in the electroplating solution. 
     
     
         16 . A method of forming a structure, the method comprising:
 forming a plurality of intermetal dielectrics (IMDs) having at least one via disposed through a dielectric layer, wherein forming each of the plurality of IMDs comprising:
 forming a seed layer in an opening in the dielectric layer, the seed layer contacting a metal feature below the dielectric layer; 
 forming a metallic protection layer over the seed layer; and 
 applying an electroplating solution in the opening to form a via layer in the opening, the electroplating solution removing the metallic protection layer and depositing the via layer such that the via layer directly contacts the seed layer; and 
   forming a metallization layer over at least one of the plurality of IMDs.   
     
     
         17 . The method of  claim 16 , wherein the electroplating solution comprises copper sulfate (CuSO 4 ) and sulfuric acid (H 2 SO 4 ). 
     
     
         18 . The method of  claim 16 , wherein the electroplating solution has an ionic copper (Cu+) concentration by weight between about 2.0% and about 3.7%. 
     
     
         19 . The method of  claim 16 , wherein applying the electroplating solution comprises submerging the metallic protection layer in the electroplating solution. 
     
     
         20 . The method of  claim 16 , wherein the metallic protection layer comprises manganese (Mn), cobalt (Co), Ti, Al, vanadium (V), chromium (Cr), zinc (Zn), or zirconium (Zr).