Noise Energy Adopted to Understand Nickel Electroplating Process

Electrochemical noise (EN) coupled with chronoamperometry and cyclic voltammetry techniques were adopted to investigate the influences of substrate, temperature ( T ), current density ( D K ) and Ni 2+ concentration ( c i ) on nickel electroplating process. The results show that the noise energy ( E D ) is weakly affected by c i as far as the concentration range concerned, and is limitedly influenced by the substrate, D K and T . The influence of D K on E D is achieved by its effect on the nucleation behavior of the initial deposit monolayer (the D K -depended nucleation behavior). E D mainly reflects the foreign work consumed in the procedure of formation of the initial deposit monolayer but not that in its subsequent growth process, and E D may be used as an index of EN to characterize the difficulty level of localized attacks (such as the formation of initial monolayer of crystallites and pits) for a defined area.