Crystal structure and microstructure of lead zirconate titanate (PZT) thin films with various Zr/Ti ratios grown by hybrid processing

Abstract

Lead zirconate titanate (Pb(Zr x Ti 1− x )O 3: PZT) thin films were fabricated on Pt/Ti/SiO 2/Si(1 0 0) substrates by a hybrid process comprising the sol–gel method and pulsed-laser deposition, using various targets of Pb(Zr x Ti 1− x )O 3 with Zr/Ti ratios of 70/30, 58/42, 52/48, 45/55 and 30/70. The effect of Zr/Ti ratio on the crystal structure and microstructure of the PZT films was investigated. The results of X-ray diffraction analysis indicated that the Zr/Ti ratio of the films fabricated using the target with a Zr/Ti ratio of 45/55 is close to that of the morphotropic phase boundary. The rosette structure was observed in Zr-rich PZT films, but not in Ti-rich PZT films. The PZT films fabricated using the target with a Zr/Ti ratio of 45/55 had a polycrystalline columnar microstructure extending throughout their thickness, and no pyrochlore phase on the surface was observed.