Surface Morphology of Lead-Based Thin Films and Their Properties

Abstract

Surface morphology of lead-zirconate-titanate [PZT(52/48)] thin films prepared by sol-gel processing on Pt/Ti/ SiO 2 /Si substrates was studied. When the atomic ratio [Pb/(Zr+Ti)] of PZT gel films was 1, rosette structure was observed in the films after annealing at 600° C for one hour. The crystal structure of the rosette was identified as perovskite and that of the other area was nonperovskite, by electron diffraction analysis. Lead deficiency in the non-perovskite phase caused by lead diffusion into the bottom electrode was detected by energy dispersive X-ray spectroscopy and Auger electron spectroscopy. In order to prepare PZT films with a smooth surface, the following four means were efficient: addition of lead excess, rapid thermal annealing (RTA), adoption of buffer layer, and preparation of crystal nucleus on the substrate.