Polarization correlation and pyroelectric properties of Pb(Zr, Ti)O-3 and La doped Pb(Zr, Ti)O-3 multilayer thin films

Polarization correlation was found in the alternatively deposited Pb(Zr, Ti )O-3 (PZT 30/70) and La doped Pb(Zr, Ti)O-3 (PLZT 17/30/70) multilayered th in films prepared by a modified sol-gel process. HRTEM results revealed tha t the multilayered thin films had their (Ill)-preferred orientation and cry stalline size of 300 nm. Dielectric constants and losses at 1 kHz for the u n-poled sample and the sample poled at 357 kV/cm were 880, 800, and 0.022, 0.019 respectively. A high pyroelectric current was observed in the PZT/PLZ T multilayered thin film near the PLZT phase transition point even after se veral thermal cycles above the phase transition temperature of the PLZT lay er. This phenomenon was termed as the self-biased dielectric bolometer (SBD B) effect, and was attributed to the induced polarization in PLZT layers by the remnant polarization in their adjacent PZT layers.