Simulation of sputter-induced roughness for depth profiling of thin film structures.

Sputtering induced surface roughening is the dominant factor that degrades depth resolution in sputter profiling of polycrystalline film samples. Due to the dependence of the sputtering yield on the crystallographic orientation, ion beam incidence angle and composition, the local sputtering rate differs from grain to grain. A simple computer program based on a model of Marton and Fine can simulate such a roughness development within one layer, an improved version can even be applied for interfaces. A further extension of the program using a model of Hauffe includes effects like shadowing and enhanced peak erosion leading to surface smoothing.