Fatigue Parameters of Lead Zirconate Titanate Thin Films

Abstract

AbstractTemperature and voltage dependence of fatigue parameters were studied for PZT thin film capacitors on the basis of our fatigue model. It was found that the coefficient of dielectric viscosity of PZT and initial internal field difference of PZT capacitors play a key role in determining fatigue rate. Jump distance was calculated from voltage dependence of decay constant, and it turned out to be essentially the same as the lattice parameter. This result indicates that vacancies (oxygen vacancies, mainly) move parallel to the polarization direction during fatigue. Activation energy was calculated from the temperature dependence of the decay constant. It was confirmed that activation energy for domain wall movement determines fatigue rate at various temperatures. This fatigue model can be used to predict the fatigue behavior and can be extended to develop an accelerated test for fatigue.