Preparation and Electrical Properties of Rhombohedral Pb(Zr_xTi_1-x)O₃ Thin Films by RF Magnetron Sputtering Method

Abstract

Rhombohedral lead zirconate titanate (PZT) thin films with a thickness of 0.3–1.2 µm were successfully grown on (111)Pb(La,Ti)O 3 /Pt/Ti/SiO 2 /Si and (111)Ir/SiO 2 /Si substrates by an RF magnetron sputtering method using a multi-target consisting of calcinated PbO and metal titanium pellets on a zirconium metal plate. The composition of the films could be controlled by adjusting the area ratio of PbO/Zr/Ti. The crystal structures of the films were sensitive to the area of PbO and the substrate temperature. The pyroelectric current, relative dielectric constant, Curie temperature, remanent polarization ( P r ) and coercive field dependence on the Zr content of the films are described. The pyroelectric coefficient of the as-prepared PZT films showed a peak from 94°C [for Pb(Zr 0.91 Ti 0.09 )O 3 ] to 36°C [for Pb(Zr 0.97 Ti 0.03 )O 3 ], which corresponded to the phase transition from the low-temperature to high-temperature rhombohedral ferroelectric phase. The fatigue characteristic was also measured using a double bipolar pulse. The PZT films preserved an initial switching charge value over a switching cycle of 10 12 .