The role of an intermetallic phase on the crystallisation of sol-gel prepared lead zirconate titanate thin films

Lead zirconate titanate (PZT) thin films have been prepared by a sol-gel method and been characterised by X-ray diffraction (XRD) and transmission electron microscopy (TEM). A metastable Pt/sub 3/Pb intermetallic phase has been identified. Perovskite PZT was found to nucleate on top of the intermetallic phase. The improved lattice match between the intermetallic (a/sub 0/=4.05 /spl Aring/) and perovskite PZT (a/sub 0/=4.035 /spl Aring/) as compared to between Pt (a/sub 0/=3.9231 /spl Aring/) and the perovskite is believed to substantially reduce the activation energy for the nucleation of perovskite on Pt. Using this effect, [111] perovskite PZT has been grown at a temperature as low as 440/spl deg/C. The crystallisation kinetics studies gave an activation energy of 179 kJ/mole for the phase transformation from pyrochlore to perovskite.