Frequency as the Greenest Additive for Metal Plating: Mathematical and Experimental Study of Forcing Voltage Effects on Electrochemical Growth Dynamics

摘要

Metal plating is a well-assessed and widespread technology. Though being a mature process (Agplating is in fact the first known application of Volta's battery in 1801, Al electrolysis was used tofabricate Napoleon III's tableware for very special occasions at the imperial French court, present-daydecorative- and hard- Cr electrodeposition thrive on a patent dating back to 1860), its successfulimplementation in many cutting-edge technologies seems the only viable approach to certain materialfabrication issues, especially in the nanoscale (e.g. state-of-the-art and next-generation ULSItechnologies). Curiously, in most cases, industrial success of this class of processes is achieved at thecost of using extremely toxic and polluting additives. This is essentially due to the poor fundamentalknowledge of the physico-chemical basis of electrochemical metal growth and, in particular, of itsdynamics. In this study we wish to highlight, from both the mathematical and the experimental pointsof view, the fact that - owing to the peculiarities of the coupled morphological and chemical dynamicprocesses going on at the electrochemical interface during metal plating at controlled potential - theapplication of a small sinusoidal forcing term is able to drive the morphology of the growing filmtowards the industrially desirable surface finish in the way currently achieved only by non-greenadditives.