Structure and optical properties of MoO3 thin films prepared by chemical vapor deposition

The structure and optical properties of polycrystalline MoO3 thin films prepared by annealing of black molybdenum layers produced by chemical vapor deposition on fused quartz substrates are determined. Three different modes of annealing are used. X-ray diffraction spectra reveal that all the films consist of MoO3 crystallized in orthorhombic form. The optical indices (n and k), the optical gap, the thickness, and the density of the films are determined. All these parameters vary as a function of the annealing conditions and film thickness. The values determined for the optical constants and the film densities are in agreement with the results found in the literature. Electrochromism is observed in these compounds.