A critical study of defect migration and ferroelectric fatigue in lead zirconate titanate thin film capacitors under extreme temperatures

Abstract

The temperature dependence of the ferroelectric switching behavior was measured for lead zirconate titanate capacitors with the composition Pb(Zr,fjoTi.40)03. Results indicated that a temperature rise contributes to an increasing rate of logarithmic decay in the polarization during repeated switching reversals. Most c a n t theories dealing w i t h polarization degradation, known as fatigue, are based on the motion of defects. In support of this phenomena, where the decay rate R(T) is proportional to exp(AQ/kT), two quantitative models are developed used to measure the thermally activated fatigue process. Fatigue curves of polarization versus number of cycles reveal that extremes in temperature are necessary to distinguish changes in the rate of fatigue, translating to a very small measured activation energy of approximately 0.05 eV. This small value leads one to believe that the mechanism responsible deals with the transport of electrondholes, not ionic defects, Caution must be taken in this conclusion since the measured value is only the thermal component for the activation energy, and does not account for a work term. &yyy~&:

Fatigue as a local phase decomposition: A switching-induced charge-injection model

“…Indeed both improvement 18,42,43 and deterioration 44,45 of fatigue endurance at higher temperatures have been reported in the literature.…”

Low-temperature switching fatigue behavior of ferroelectric SrBi2Ta2O9 thin films

“…In spite of intensive studies in past decades, the low-temperature performance of ferroelectric thin films has not been understood as well as the room-temperature one. 1,2 Nevertheless, the temperature dependence of ferroelectric properties is one of the interesting issues, in view of not only technological applications, but also in a fundamental sense. 3 In fact, FRAM devices may undergo service at a low-temperature circumstance, such as in space.…”

Simulation of oxygen vacancy induced phenomena in ferroelectric thin films

“…The effect of temperature obtained both from our simulation (curves) and the experimental result of Paton et al 31 (symbols) are shown in Fig. 8.…”