Modification and Sputtering of Inhomogeneous Multilayer Oxidized Metal Films by Low-Current Argon Ion Beams

Results of generation of various suboxide layers on various thin oxidized niobium films by modification and sputtering of their surfaces with low-current argon ion beams are reported. Niobium films of various thicknesses were grown by magnetron sputtering on oxidized silicon substrates. Few stages of delicate ion bombardment were performed. The surface of films was studied by means of non-destructive methods of X-ray photoelectron spectroscopy and angle-resolved X-ray photoelectron spectroscopy. Chemical and phase film profiling was performed. It was found that during air exposure of niobium films of various thicknesses, layers of pentoxide and various stoichiometric and non-stoichiometric oxides had been generated. During ion bombardment, composition and thicknesses of the films did not change. Numerical modelling results showed that by delicate ion bombardment atoms of oxygen were mostly sputtered. It was the surface pentoxide niobium layer that was sputtered and modified. It was found that different layers of stoichiometric suboxides and pentoxides of other phases different from the initial phases had been formed. The composition of surface suboxide layers changed slightly. The results of this research show opportunity of generation of suboxide layers of various composition and thicknesses by changing parameters of ion irradiation of metal film surface.