Structure and crystallization of amorphous metal oxide films
High resolution electron microscopic observations have been made on amorphous and crystalline metal oxide films. The specimen films were prepared by vacuum-evaporation of metal oxide powder from alumina coated tungsten basket onto clean glass substrates at room temperature. The films were deposited to a thickness of 100 Å, monitored with quartz crystal oscillating microbalance. The films were wet-stripped from the substrates and then mounted on gold holey films which were supported by standard gold electron microscope grids. Transmission electron micrographs were taken with JEM 100-C electron microscope under axial illumination. The microscope was equipped with an objective lens with Cs=1.8 mm and operated at 100 kV.Figure 1 shows an electron micrograph and an electron diffraction pattern of as-deposited WO3 film. The thickness of the film is assumed to be less than 50 Å, since the 100 Å thick film was floated on the distilled water for 20 minutes for thinning by dissolution.
