Structural characterization of PbTiO3 thin films prepared by ion beam induced CVD and evaporation of lead

PbTiO3 thin films have been prepared by a method that combines the ion beam induced chemical vapour deposition from a volatile Ti(OCH2CH3)(4) precursor and the evaporation of lead. The growing film is continuously bombarded with a beam of O-2(+) ions of similar to 1 000 eV of kinetic energy. The structure of the films has been characterized by X-ray diffraction, X-ray absorption spectroscopy and electron diffraction at a transmission electron microscope (TEM). Analysis of the electron energy-loss spectra acquired at the TEM microscope and collection of energy filtered images have provided information about the element distribution in the original sample. The composition, microstructure and optical quality of the films have been checked by X-ray photoelectron spectroscopy, scanning electron microscopy with a fluorescence facility and ultraviolet-visible spectroscopy. The films are very homogeneous and transparent. After calcination at T greater than or equal to 723 K they presented the perovskite structure of PbTiO3. The crystallization process of the films followed the sequence: amorphous structure (original sample) --> PbO (litharge) + TiO2 (amorphous) (473 K) --> PbTiO3 (perovskite) (723 K). The implications of the ion bombardment on the composition, structure and microstructure of the films are discussed.