COMPOSITIONAL CONTROL OF FERROELECTRIC FATIGUE IN PEROVSKITE FERROELECTRIC CERAMICS AND THIN-FILMS

The mechanism and control of ferroelectric polarization fatigue (loss of polarization with cycling) in donor- and acceptor-doped BaTiO3 cera mics and Pb(Zr1-xTix)O-3 (PZT) thin films has been investigated. Exper imental results clearly demonstrate that fatigue behavior is related t o the defects within the materials. Donor-doped BaTiO3 ceramics showed significantly improved fatigue characteristics when compared with acc eptor-doped materials. A similar but reduced effect has been observed in donor-doped PZT thin films. The electric-field-assisted migration o f charged species within ferroelectric materials may be responsible fo r the degradation/fatigue behavior. Results support the expectation th at oxygen vacancies play an important role in fatigue that occurs as a result of polarization switching.