Characterization of native oxide layers on amorphous Fe73.5Si15.5B7Cu1Nb3 before and after high-energy heavy ion irradiation by X-ray photoelectron spectroscopy (XPS)

The surface oxide layers formed in atmosphere at room temperature (native oxide) on a FINEMET alloy Fe73.5Si15.5B7Cu1Nb3, before and after high energy heavy ion (Ni+11, 150 MeV) irradiation, were characterized by X-ray photoelectron spectroscopy (XPS). The major cationic species in layers were found to be Fe3+, B3+, Si4+, Nb2+/Nb4+ while Cu was present in the elemental form. The native oxide layer on the irradiated specimen contained higher amounts of oxides of Si and B in comparison unirradiated specimen. After irradiation both Nb and Cu were found to be depleted on the surface. The thickness of oxide layer formed on the surface is estimated to be approximately 25 and 40 Angstrom on the virgin and irradiated specimen, respectively. (C) 2001 Elsevier Science B.V. All rights reserved.