Electrical Properties of Low-Temperature (450°C) Pb(Zr,Ti)O 3 Films Prepared in Quasi-Metallic Mode by RF Reactive Sputtering

Abstract

Ferroelectric lead zirconate titanate (PZT) thin films were prepared on Pt/Ti/SiO2/Si substrates from a ZrTi (50%/50%) alloy target combined with PbO pellets using an rf reactive sputter deposition technique. Perovskite PZT films were obtained at a growth temperature as low as 450°C in the quasi-metallic mode. Crystalline structure, depth profiles, ferroelectric and dielectric characteristics of the films prepared from the (ZrTi+30%PbO) target were investigated. The interdiffusion between the PZT film and the Pt/Ti/SiO2/Si substrate was suppressed by the low-temperature sputtering. The remanent polarization, leakage current and dielectric constant decrease with increasing growth temperature. The perovskite films prepared at 450°C exhibit the remanent polarization of 20 µC/cm2, the coercive field of 150 kV/cm, the leakage current smaller than 10-6 A/cm2 at the electric field lower than 235 kV/cm, and the dielectric constant as high as 561.