Novel chemical synthetic route and characterization of tungsten diselenide thin films

Polycrystalline WSe2 semiconductor thin films were obtained by relatively simple chemical bath deposition method using the sodium tungstate, tartaric acid, hydrazine hydrate and sodium selenosulphate as a precursor sources in an aqueous alkaline medium at room temperature. Various preparative conditions of WSe2 thin films are outlined. The grown films were found to be uniform, well adherent, brown in color. The films were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), optical absorption and electrical conductivity properties. The optical study shows a direct band gap nature with band gap energy 1.48 eV, and having specific electrical conductivity of the order of 10−2 Ω−1 cm−1 showing n-type conduction mechanism.