Electrochemical Properties of Copper Electroplating with Supercritical Carbon Dioxide Emulsion

The electrochemical properties of Cu electroplating with supercritical CO2 (Sc-CO2) emulsion mixed into the plating solution are reviewed. A rotating disk electrode (RDE), capable of operating under high pressure, was prepared for the electrochemical evaluation by convection voltammetry and electrochemical impedance spectroscopy (EIS) measurements. In the mass transfer process, it was confirmed that the mixture of Sc-CO2 and plating solution promoted the transport of Cu ions by convection. In the electrode activation reaction process, in addition to the increase in polarization resistance due to the adsorption of the polyethylene glycol (PEG) complex, Sc-CO2 was found to increase the polarization resistance and further suppress deposition.