High Resolution Morphological Changes of Cu, Ni, Al, and Au Surfaces Due to Atmospheric Corrosion

As atmospheric corrosion of electrical contacts is a common cause of failure in electronics industry and at the same time miniaturization is a requirement in any modern electronic device, it is important to study the effects of corrosion in the surface morphology of metals widely used in that industry sector, such as gold, copper, nickel, and aluminium. Here, atomic force microscopy (AFM) has been used with that purpose, analysing flat surfaces of those metals both before and after exposure by several weeks to the effects of a contaminated atmosphere containing both NO
₂
and SO
₂
at constant temperature and humidity. Results indicate all metals suffered changes both in surface morphology and roughness. AFM phase mode images also indicated the occurrence of different species on the Ni and Cu surfaces after 11 weeks of exposure. Evidence of defects due to the corrosion attack was only observed for Ni.