Method and apparatus for plating substrate with copper

Abstract

The present invention relates to a method and apparatus for separating out metal copper according to an electroplating of copper using, for example, a solution of copper sulfate to produce copper interconnections on a surface of a substrate. The substrate is brought into contact, at least once, with a processing solution containing at least one of organic substance and sulfur compound which are contained in a plating solution. Thereafter, the substrate is brought into contact with the plating solution to plate the substrate.

What is claimed is:  
     
         1 . A method to fill a metal in fine grooves formed in a surface of a substrate, comprising: 
 bringing the substrate into contact with a plating solution;    plating the substrate with the plating solution electrically with an electric current to form a plated metal film;    stopping the electric current to interrupt the plating before the plated metal film reaches a desired film thickness;    etching the plated metal film electrolytically with a direct electric current opposite to the electric current during plating; and    plating the substrate having the etched metal film to form a remaining film thickness to reach the desired film thickness.    
     
     
         2 . A method according to  claim 1 , wherein a current density of the direct electric current during etching in a range of 1 mA/cm 2  to 30 mA/cm 2 .  
     
     
         3 . A method according to  claim 1 , wherein the direct electric current for performing etching is supplied for a period of time in a range of about 0.5 seconds to 30 seconds.  
     
     
         4 . A method according to  claim 1 , wherein said metal is copper.  
     
     
         5 . A method according to  claim 1 , wherein the etching is performed with the plating solution.  
     
     
         6 . A method according to  claim 1 , wherein the plating of the substrate having the etched metal film is performed with the plating solution.  
     
     
         7 . A metal for plating a substrate with copper, comprising: 
 bringing, at least once, a substrate into contact with a processing liquid offering surface activity of a substrate surface and/or increasing wettability between a plating solution and the substrate surface;    performing one of removing the processing liquid from the substrate and drying the substrate; and    bringing the substrate into contact with the plating solution to plate the substrate after performing one of removing the processing liquid from the substrate and drying the substrate.    
     
     
         8 . A method according to  claim 7 , wherein said performing includes one of rotating the substrate to spin off the processing liquid from the substrate, rotating the substrate and applying a gas below to the substrate, and passing the substrate through a forced air.  
     
     
         9 . A method according to  claim 7 , wherein said performing is successively performed after the substrate is brought into contact with the processing liquid by one apparatus.