Structural and electrical properties of excess PbO doped Pb(Zr 0.48Ti0.52)O3 thin films prepared by a MOD process

摘要

Pb(Zr0.52Ti 0.48)O3 thin films with 30 mol % excess Pb were deposited on Pt/Ti/SiO2/Si(100) substrates at 600 °C by a metal-organic decomposition process. The Pb/Zr ratio measured by Rutherford backscattering spectroscopy is higher than the stiochiometric ratio. X-ray diffraction measurements show that the PZT film has a perovskite structure but it also contains a PbO2 phase High resolution transmission electron microscope studies reveal that the nano sized PbO2 crystals are dispersed quite uniformly in the film. The film exhibits an abnormally slim polarization loop at low applied electric field probably as a result of domain pinning by the PbO2 crystals. The pinning effect can be overcome by applying a sufficiently high field. The film had good fatigue properties even with the presence of the PbO2 crystals.