Abstract
Copper electrodeposition in a gel electrolyte has been studied by an electrochemical impedance spectroscopy (EIS). The electrochemical impedance was measured in a gel electrolyte containing various chloride concentrations. An inductive loop and a second capacitive loop were described on the Nyquist plot of electrochemical impedance at low frequency. These are called Faradaic impedance, which originates from the elementary steps of an electrode reaction. Warburg impedance was observed at low frequency in the diffusion limiting current region, indicating the contribution of the Cu(II) diffusion from the solution bulk to the electrode surface. The electrodeposition model of copper in the gel electrolyte was proposed on the basis of above-mentioned results. The numerical simulations were performed to confirm the proposed electrodeposition model and to obtain the kinetic parameters. Moreover, the influence of chloride was discussed from the obtained kinetic parameters.
