Fatigue Characteristics of Sol-Gel Derived Pb(Zr, Ti)O₃ Thin Films

Abstract

Fatigue mechanisms of sol-gel derived Pb(Zr–Ti)O 3 (PZT) thin films and the effects of La addition on the fatigue characteristics were investigated. For PZT(40/60) and PZT(53/47), the remanent polarization ( P r ) and the coercive field ( E c ) decreased with switching cycles. These properties were restored by heating the fatigued films above their Curie temperature. This result indicates that domain pinning is the dominant fatigue mechanism for PZT(40/60) and PZT(53/47). On the other hand, for PZT(70/30), P r was almost constant and E c increased with switching cycles; this implies that the fatigue mechanism for PZT(70/30) is different from that for PZT(40/60) and PZT(53/47). Addition of La to the PZT(53/47) film reduced space charge in the film, though did not improve fatigue characteristics.