Effect of base electrode on the crystallization and electrical properties of PLT

Lead lanthanum titanate (28% La) films, 900-1500 A thick, have been deposited by the sol-gel technique on Ir/Si and Pt/Ti/SiO2 substrates. The films have been rapidly thermal annealed for 1-4 min. at 650 °C and have been characterized by X-ray diffractometry, scanning electron microscopy and by electrical measurements. The dielectric constant of the PLT films deposited on the Pt electrodes reached a maximal value of 660, while for those deposited on the IT electrodes it reached maximal value of 775. The variation of the values of the dielectric constants of the different samples appears to be controlled mainly by the concentration of Pb in the films.