WO3:Mo and WO3:Ti Thin Films Deposited by Spray Pyrolysis: The Influence of Metallic Concentration on Physical Properties: An Electron Microscopy and Atomic Force Study
WO3:Mo and WO3:Ti thin films have been deposited on FTO/Glass substrates by the pulsed chemical spray technique at a substrate temperature of Ts = 450°C. The influence of Mo and Ti doping on the structural, electrical, and optical behavior of WO3 thin films, has been studied by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), Ultra Violet and Visible Spectrometry (UV-VIS), and Surface Conductivity Methods (Four Points). Doped WO3 films presents similar polycrystalline structures but with noticeable modifications in surface configurations at micrometric and nanometric levels, as the Mo and Ti concentration is systematically increased in the starting sprayed solution. From processed High-Resolution Electron Micrographs (HREM), a low density of structural defects was found on pure and doped WO3 grains. This lead to conclude that variations in films surface characteristics are mainly related with metallic doping concentrations which in turn, have noticeable influence in electrical and optical behaviors reported in this work.
Luz Stella Gomez-Villalba
D. Acosta et al., "WO3:Mo and WO3:Ti Thin Films Deposited by Spray Pyrolysis: The Influence of Metallic Concentration on Physical Properties: An Electron Microscopy and Atomic Force Study", Solid State Phenomena, Vol. 286, pp. 49-63, 2019