Highly oriented V2O5 nanocrystalline thin films by plasma-enhanced chemical vapor deposition

Plasma-enhanced chemical vapor deposition of vanadium pentoxide thin films from a vanadyl(IV) beta-diketonate compound has been performed in a low-pressure reactor under different operating conditions. The effect of various parameters, such as the: flow rates of the carrier and reactive gas and the substrate temperatures, on films composition, microstructure, and morphology was investigated in detail. Controlled variations of the synthesis conditions allowed a fine modulation of the sample properties, as shown by XRD and AFM analyses. In particular, at 200 degrees C and moderate oxygen flow, nanophasic V2O5 with a strong (001) preferential orientation could be easily obtained. The composition and purity of the films are studied by XPS and SIMS analyses, with special regard to film-substrate interdiffusion phenomena. Optical properties of the films are also investigated.