Structural, optical and microscopic studies of tungsten substituted molybdenum diselenide thin films

A modified chemical bath deposition method has been developed to prepare Mo1−xWxSe2 layer type semiconductor thin films. Various preparative conditions of the thin films are outlined. The films were characterized by X-ray diffraction, optical absorption, electrical measurements and thermoelectric techniques. The grown films were found to be uniform, well adherent to substrate and brown in color. The X-ray diffraction (XRD) study indicates the polycrystalline nature in single hexagonal phase over whole range of composition. Analysis of absorption spectra gave direct type of band gap, the magnitude of which increases slightly as tungsten content in the film is increased and electrical conductivity at room temperature was found to be 10−5 to 10−2 (Ω cm)−1. All the films show n-type conductivity.