Different fatigue behaviors of SrBi2Ta2O9 and Bi3TiTaO9 films: Role of perovskite layers

To investigate the role of the perovskite layers on fatigue behaviors, SrBi 2Ta2O9(SBT) and Bi3TiTaO9 (BTT) films were prepared by pulsed laser deposit ion using 15% Bi-excess bulk targets. The SBT and the BTT films grown at th e similar deposition conditions showed similar growth behaviors, electrical properties, and retention characteristics. However, these films showed ver y different fatigue behaviors. The difference should come from the oxygen s tability in the perovskite layer. Our work demonstrates that oxygen stabili ty of the perovskite layers, as well as the self-regulating adjustment of t he Bi2O2 layers, should be considered in the search for new candidate mater ials for nonvolatile ferroelectric memory devices. (C) 1999 American Instit ute of Physics. [S0003-6951(99)02243-3].