Piezoelectric and dielectric reliability of lead zirconate titanate thin films

This work was directed toward developing a database for the long-term relia bility of the transverse piezoelectric coefficient d(31) under both unipola r and bipolar drive. Under unipolar drive, the films showed excellent relia bility, with 99% of the devices surviving to 10(9) cycles. However, both ag ing and low amplitude bipolar drive resulted in rapid degradation of d(31) due to backswitching of the ferroelectric domains. Both thermal and ultravi olet (UV) imprint prevented backswitching and resulted in improved aging an d bipolar degradation behavior. Additionally, the UV imprinted samples show ed nonlinear aging due to the presence of an internal space charge field th at developed from photo-induced charge carriers.