Determination method of additive amount in copper electrorefining

摘要

PROBLEM TO BE SOLVED: To rapidly determine the optimum amts. of the additives to be added by determining the amts. of the additives so as to minimize both of the surface roughness of electrodeposited matter (copper) calculated by prescribed mathematical expressions and the variation in the surface roughness by current densities. SOLUTION: The additives are used to smooth the surface of the electrodeposited matter (electrolytic copper). The optimum amts. of the respective additive are determined from the prescribed mathematical expression. Namely, such amts. of the additives as to minimize both of the surface roughness (Rz) of the cathode electrodeposited matter obtd. by a Hull cell test and the variation () in the roughness by the different current densities are determined by the equations I, II. In the equations, Ctu is the amt. of the thiourea to be added, Cglue is the amt. of the glue to be added and CC1 is the concn. of chlorine ions. The Hull cell test described above has the advantages that the rapid and easy measurement of the electrodeposition state and the surface roughness thereof at the different current densities is possible and, therefore, the determination of the respective additives is eventually rapidly executable via the two equations described above.