J. Phys. IV France 08 (1998) Pr9-53-Pr9-56
Ferroelectric improvements of (Pb,Ca)TiO3 thin filmsM.L. Calzada, R. Jimenez, P. Ramos, M.J. Martin and J. Mendiola
Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid, Spain
Ca-modified lead titanate thin films of nominal composition Pb0.76Ca0.24TiO3, deposited on Pt/TiO2/(100)Si substrates, have been prepared by sol-gel spin-on process. Crystallization of the samples was promoted by Rapid Thermal Processing (RTP). Different PbO excesses in the precursor solution and different heating rates during the RTP have been tested. Hysteresis loops improve and switching currents increase when films are deposited from solutions with a 10 mole% PbO excess and are crystallized with a heating rate of 30°C/sec. These improvements are associated to a good fit of the film stoichiometry and to a reduction of the substrate-ferroelectric interface. Postannealing of the crystallized (Pb,Ca)TiO3 films, leads to a favourable distribution of the charged defects liberating domains and facilitating their switching.
© EDP Sciences 1998