Total-dose radiation effects on sol-gel derived PZT thin films

Sol-gel derived PZT (lead zirconate-titanate) thin films were irradiated to a total-dose of 1 Mrad(Si) or 86 krad(PZT) under open-circuit bias. An asymmetric distortion in the hysteresis curves was observed. The distortion depends on the polarization state of the capacitor before irradiation. Postirradiation electrical cycling makes the hysteresis loops symmetric initially, but results in fatigue effects. The leakage and switching current behavior after irradiation and post-rad cycling were studied using a static current versus voltage measurement. Retention and fatigue properties are not worsened after irradiation except for the polarization reduction. The radiation effects are consistent with the sheet charge model. The fatigue effects due to post-rad cycling are consistent with an increase in the space-charge regions near the electrodes or oxygen-deficient dendrite growth.< >