CDV PREPARATION OF WSE2 THIN-FILMS

This paper deals out with the preparation conditions of WSe2 thin films. Samples are prepared by using a classical CVD apparatus with WF6 and H2Se as carrier agents. Various substrates (quartz, silica, alumina and mica) have been used, the range of temperature being 300-degrees-C to 700-degrees-C. The films have been characterized by Rutherford Backscattering Spectroscopy (RBS), X-ray diffraction, Energy Dispersion Analysis of X-ray (EDAX), optical and electron microscopies. From RBS measurements it is found an atomic ratio N(Se)/N(W) = 2 within some particular conditions. The films are crystallized and present a preferential orientation. The optical absorption spectra are similar with those of single crystals and the photoelectrochemical stability is very good.