Structural properties of titanium oxide films deposited in different RF plasma atmospheres
I. Luciu1,2, R. Bartali2, V. Micheli2, G. Gottardi2, N. Laidani2
1 Physics Dep. University of Trento, Povo, 38100 Trento, Italy
2 FBK-CMM, Sommarive 18, Povo, 38100 Trento, Italy
Titanium oxide thin films, grown on silicon substrates by radio-frequency sputtering, were studied. Three kinds of plasma atmospheres were used during the process: Ar and Ar-O2 and Ar-H2 mixtures with different concentrations of oxygen and hydrogen. The films were grown at room temperature and under a self-bias voltage on the cathode of -550 V. Post-deposition films annealing in vacuum was performed at 400°C. Both as-deposited and annealed films were analyzed by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) to characterize them from a chemical, electronic and crystalline structure point of view. The effects of the different process parameters (gas type, composition of the gas mixtures) and of annealing on the oxide stoichiometry and the valence band characteristics were investigated.