Lead zirconate-titanate films prepared from soluble powders

Precursor powders for Pb(Zr1-xTix)O-3 (PZT) thin films were produced by the reaction of zirconium- and titanium-n-propoxides with acetylacetone and lead acetate trihydrate. The subsequent complete removal of volatile components yielded powders that can be handled in air. The powders are indefinitely stable under ambient conditions. High molarity (>2m) coating sols were prepared by dissolution of the precursor powders in mixtures of 1,3-propanediol, triethanolamine (TEA) and water. Excess amounts of lead to compensate lead loss during firing were easily introduced into these solutions. The deposition of these sols on steel substrates and tiring at 600 degrees C yielded PZT films. Many physical parameters like film thickness, morphology and electrical performance could be influenced by choice of the solvent mixture composition and oxide content of the sols. Depending on the preparation dielectric permittivities, epsilon(r) of up to 840 were measured at 1 kHz. By hysteresis measurements at 50 Hz and a field amplitude of 50 V/mu m a remanent polarization of about 40 mu C/cm(2) and coercivity of about 8 V/mu m was obtained. The films were stable against dielectric breakdown up to 70 V/mu m.