Anode Effects in Electroplated Cu Film

Abstract

In order to study anode effects in Cu electroplating, we investigated the characteristics of the Cu films electrodeposited on Cu seed layer and the surface change of anodes, by using Cu (soluble) and Pt (insoluble) anodes. For the case of Cu anode, the brownish passivation layer was formed on the surface of Cu anode, and this was mainly composed of by-products which was formed by reaction of impurities in electrolyte with copper anode. In use of Pt anode, the O 2 bubbles on the anode surface were occurred. The current density in bath for the case of Cu anode was larger than that of Pt anode and increased after 300 s of plating time had elapsed. In formation of the electroplated Cu films, the deposition rate of Cu films electroplated by using Cu anode was larger and the density of film plated by using Cu anode was higher than those by Pt anode.