Antiferroelectric-ferroelectric switching and induced strains for sol-gel derived lead zirconate thin layers

Abstract

Lead zirconate (PZ) thin layers were formed by a sol-gel method and crystallized with a pseudocubic (111) or (100) preferred orientation. The field-forced antiferroelectric (AFE)-to-ferroelectric (FE) phase transformation behavior was examined by Sawyer–Tower measurements. Dielectric properties were measured as a function of temperature and frequency, and the field-induced transformational strain was measured by interferometry. Both the high-field hysteresis behavior and the temperature-dependent weak-field dielectric properties were found to be strongly dependent on preferred orientation. An increase in the remanent polarization and dielectric constant was observed under high electric field strengths at room temperature, or for lower field strengths at higher temperature. Strains as large as 0.7% were determined for the field-forced AFE-to-FE transformation. AFE-to-FE switching was demonstrated with full saturation at room temperature for high dielectric strength (100 MV/m) thin layers (300 nm).