Preparation and Characterization of Tungsten Trioxide (WO3) Thin Films

The thin films of WO3were prepared on cleaned microscopic glass substrates by the electron beam evaporation technique. The films were coated at room temperature using pure WO3pellets as source. The prepared films were further post heat treated at different temperatures (100°C to 350°C) for about 1hr in air. The optical properties of WO3 thin films were studied in detail. The increase in the density of the film as the annealing temperature increases have been confirmed by the transmittance spectra. The film annealed at 250°C shows a strong photoluminescence peak. The peak intensity is found to be less for all other temperature. The observed results were discussed in terms of crystalline nature of WO3.