Material for copper electroplating, method for manufacturing same and copper electroplating method

Abstract

A copper electroplating material capable of exhibiting increased easy-dissolution properties, to thereby minimize formation of an insoluble residue. Basic copper carbonate is formed in a reaction tank by deposition and heated to a temperature of between 250° C. and 800° C. and preferably between 350° C. and 600° C. in an atmosphere which does not form a reducing atmosphere which does not form a reducing atmosphere, to thereby be subjected to thermal decomposition, resulting in providing easily soluble copper oxide. The copper oxide is washed with water and dewatered using, for example, a centrifugal separator. Then, the copper oxide is dried.

What is claimed is:  
     
         1 . A method for manufacturing a copper electroplating material adapted to be fed as a copper ion supply to a copper plating bath in copper electroplating, comprising the step of: 
 heating basic copper carbonate to a temperature of 250° C. to 800° C. in an atmosphere which is not rendered reductive to carry out thermal decomposition of the basic copper carbonate, to thereby produce easily dissolved copper oxide constituting the copper electroplating material.    
     
     
         2 . A method for manufacturing a copper electroplating material adapted to be fed as a copper ion supply to a copper plating bath in copper electroplating, comprising the step of: 
 heating basic copper carbonate to a temperature of 250° C. to 800° C. in an atmosphere which is not rendered reductive to carry out thermal decomposition of the basic copper carbonate, to thereby produce easily dissolved copper oxide; and    washing the easily dissolved copper oxide with water to provide the copper electroplating material.    
     
     
         3 . A method as defined in  claim 1  or  2 , wherein the basic copper carbonate is obtained by mixing an aqueous solution of a copper salt selected from the group consisting of copper chloride, copper sulfate and copper nitrate and an aqueous solution of carbonate of a material selected from alkaline metal, alkaline earth metal and ammonia(NH 4 ) with each other, reacting both aqueous solutions with each other while heating them, to thereby deposit a reaction product, and separating the reaction product by filtration.  
     
     
         4 . A copper electroplating material fed as a copper ion supply to a copper plating bath in copper electroplating, comprising easily dissolved copper oxide formed by heating basic copper carbonate to a temperature of 250° C. to 800° C. in an atmosphere which is not rendered reductive to subject it to thermal decomposition.  
     
     
         5 . A copper electroplating material fed as a copper ion supply to a copper plating bath in copper electroplating, comprising easily dissolved copper oxide formed by heating basic copper carbonate to a temperature of 250° C. to 800° C. in an atmosphere which is not rendered reductive to subject it to thermal decomposition, to thereby obtain a thermal decomposition product and then washing the thermal decomposition product with water.  
     
     
         6 . A copper electroplating material as defined in  claim 4  or  5 , wherein the basic copper carbonate is obtained by mixing an aqueous solution of a copper salt selected from the group consisting of copper chloride, copper sulfate and copper nitrate and an aqueous solution of carbonate of a material selected from alkaline metal, alkaline earth metal and ammonia(NH 4 ) with each other, reacting both aqueous solutions with each other while heating them, to thereby deposit a reaction product, and separating the reaction product by filtration.  
     
     
         7 . A copper electroplating material as defined in  claim 5 , wherein the basic copper carbonate is obtained by mixing an aqueous solution of a copper salt selected from the group consisting of copper chloride, copper sulfate and copper nitrate and an aqueous solution of carbonate of a material selected from alkaline metal, alkaline earth metal and ammonia(NH 4 ) with each other, keeping the mixed solution at a pH within a range of between 7.0 and 9.0, reacting both aqueous solutions with each other while heating them, to thereby deposit a reaction product, and separating the reaction product by filtration.  
     
     
         8 . A copper electroplating material as defined in  claim 4  or  5 , which is fed to a plating bath in which an insoluble anode and a plated object acting as a cathode are arranged.  
     
     
         9 . A copper plating method comprising the steps of: 
 feeding a copper electroplating material as defined in  claim 4  or  5  to a plating bath in which an insoluble anode and a plated object acting as a cathode are arranged; and    subjecting the plated object to copper plating.    
     
     
         10 . A method for manufacturing a copper electroplating material fed as a copper ion supply to a copper plating bath in copper electroplating, comprising the steps of: 
 mixing an aqueous cupric chloride solution and an aqueous solution containing a carbonate ion with each other to prepare a mixed solution;    keeping the mixed solution at a pH within a range of between 8.0 and 9.0 and a temperature within a range of between 75° C. and 90° C. to form basic copper carbonate; and    subjecting the basic copper carbonate to solid-liquid separation and washing, so that the basic copper carbonate may have a chlorine concentration of 80 ppm or less.    
     
     
         11 . A method for manufacturing a copper electroplating material fed as a copper ion supply to a copper plating bath in copper electroplating, comprising the steps of: 
 mixing an aqueous cupric sulfate solution and an aqueous solution containing a carbonate ion with each other to prepare a mixed solution;    keeping the mixed solution at a pH within a range of between 8.0 and 9.0 and a temperature within a range of between 75° C. and 90° C. to form basic copper carbonate; and    subjecting the basic copper carbonate to solid-liquid separation and washing, so that the basic copper carbonate may have a SO 4  concentration of 200 ppm or less.    
     
     
         12 . A method for manufacturing a copper electroplating material fed as a copper ion supply to a copper plating bath in copper electroplating, comprising the steps of: 
 feeding an aqueous cupric sulfate solution and an aqueous solution containing a carbonate ion to a reaction tank while adjusting a feed ratio between both aqueous solutions so that a molar ratio of a copper ion to a carbonate ion in a mixed solution of both aqueous solutions may be within a range of between 1:1.3 to 2.6;    keeping a temperature of the mixed solution at a level of 95° C. or more without pH control of the mixed solution to produce basic copper carbonate; and    subjecting the basic copper carbonate to solid-liquid separation and washing, to thereby provide the copper electroplating material constituted by the basic copper carbonate.    
     
     
         13 . A method for manufacturing basic copper carbonate fed as a copper ion supply to a copper plating bath in copper electroplating, comprising the steps of: 
 feeding an aqueous cupric sulfate solution and an aqueous solution containing a carbonate ion to a reaction tank while adjusting a feed ratio between both aqueous solutions so that a molar ratio of a copper ion to carbonate ion in a mixed solution of both aqueous solutions may be within a range of between 1:2.3 to 4.6;    keeping a temperature of the mixed solution at a level of 95° C. or more without pH control of the mixed solution to produce basic copper carbonate; and    subjecting the basic copper carbonate to solid-liquid separation and washing, to thereby provide the copper electroplating material constituted by the basic copper carbonate.