Defects and Leakage Current in PbTiO3 Single Crystals
Single crystals of PbTiO3 (PT) were grown by a self flux method, and effects of lattice defects on the leakage current properties were investigated. While PT crystals annealed in air at 700 oC showed a leakage current density of the order of 10-5 A/cm2, annealing under a high oxygen partial pressure of 35 MPa increased leakage current density to 10-4 A/cm2. The increase in leakage current by the oxidation treatment provides direct evidence that electron hole is a detrimental carrier for the leakage current property of PT at room temperature. The vacancies of Pb are suggested to act as an electron acceptor for generating electron holes.
K. Katayama, K. Kato, T. Takenaka, M. Takata and K. Shinozaki
M. Tamada et al., "Defects and Leakage Current in PbTiO3 Single Crystals", Key Engineering Materials, Vol. 350, pp. 77-80, 2007