Study of Erbium Oxidation by XPS and UPS
X-ray and UV photoelectron spectroscopy (XPS and UPS were used for studying the oxidation of Er films deposited on Ta substrate under ultra-high vacuum.Oxidation has been carried out at room temperatue with an oxygen pressure of 2x10-5 mbar.Erbium exposition to oxygen produces ; Er2O3 and a hydoxide.Subjecting the sample to a post annealing treatment at 750 °C dissociates the hydroxide and produces additional Er2O3.UPS and XPS valence band gives evidence that the formed oxide is Er2O3.
N. Guerfi et al., "Study of Erbium Oxidation by XPS and UPS", Materials Science Forum, Vols. 480-481, pp. 193-196, 2005