RHYTHMIC LAMELLAR CRYSTAL GROWTH IN ELECTROLYTIC COPPER DEPOSITION

The rhythmic electrodeposition of copper in presence of o-phenanthroline (o-phen) is caused by two reaction products of o-phen. They occur in dependence on potential at the metal/solution interface and act as inhibitors. At overpotentials η above 280 mV (εh = + 30 mV) a reduction product of o-phen is formed. By its influence, the surface increases by roughening; consequently η decreases. Below η = 280 mV no reduction product arises; here only the cation of o-phen acts as a much weaker inhibitor and levels the surface, so that overpotential increases. Measurements of the coverage show two steps of potential dependent adsorption. © 1968.