Effects of sputtering on the surface composition of niobium oxides

Abstract

X‐ray photoelectron spectroscopy and Auger electron spectroscopy have been used to study the effect of argon ion bombardment on the composition of NbO, NbO2, and Nb2O5. Preferential sputtering of oxygen from the surfaces of these oxides was observed. The use of lower ion energy (500 eV) resulted in more reduction of the oxides than that observed while using higher energy (2000 eV) ions. This energy dependence of preferred sputtering is attributed to changes in the sputtering mechanism. Difficulties associated with interpreting the results of sputter depth profiling of oxidized niobium surfaces are discussed.