Characterization of pitting corrosion in aluminum films by light scattering

Abstract

We report a detailed study of the morphology of pits formed by corrosion of aluminum thin films using an in-plane light scattering technique. We show that the corrosion front of the Al thin film can be treated as a quasi-two-level random rough surface. Based on an elastic diffraction theory, we are able to determine the average depth, the area, and the density of pits, as well as the fractal dimension of the surface. Using the advantages of light scattering, one can quantify the morphological parameters of corroded films in situ and nondestructively.