Ferroelectric properties of Pb(Zr,Ti)O-3 heterolayered thin films for FRAM applications

Abstract

Ferroelectric PZT (20/80)/PZT (80/20) heterolayered thin films were fabricated by spin-coating method on a Pt/Ti/SiO2/Si substrate alternately. using PZT (20/80) and PZT (80/20) alkoxide solutions. All PZT heterolayered films show dense and homogeneous structure without the presence of the rosette microstructure. The relative dielectric constant and dielectric loss at 100 kHz of the PZT-6 film were about 355 and 0.016, respectively. As the number of coats increased, remanent polarization increased, the coercive field decreased and the values of the PZT-6 film were 16.14 muC/cm(2) and 97.1 kV/cm, respectively. Leakage current density of the PZT-6 heterolayered film was 2.5 X 10(-7) A/cm(2) at 5 V. (C) 2002 Elsevier Science B.V. All rights reserved.