J. Phys. IV France 08 (1998) Pr9-61-Pr9-64
Influence of processing parameters on dielectric properties of PZT thin films on steel substratesS. Seifert, P. Löbmann and D. Sporn
Fraunhofer-Institut für Silicatforschung (ISC), Neunerplatz 2, 97082 Würzburg, Germany
PZT thin films with a stoichiometry close to the morphotropic phase boundary were prepared on metallic susbtrates by a modified sol gel processing. Single layer film thicknesses of about 0.9 µm were obtained, by multiple coatings films up to 5 µm could be prepared. Hysteresis loops were obtained with a remanent polarization of about 35 µC/cm2 and a coercivity of about 10 V/µm for an applied field strength of 50 V/µm. Dependent on the solvents used for the sol preparation the dielectric breakdown was about 50 V/µm for films with a high amount of triethanolamine (TEA) in the solution and more than 70 V/µm for films prepared with less TEA. By chemical analysis of the crystalline samples a significant lead loss was found compared to the lead content of the deposition solutions. By XRD measurements secondary phases were found for a molar lead excess of about 35 % in the deposition solutions. The influence of the lead content on the small and large signal dielectric properties was investigated. Best ferroelectric behavior was found for a molar lead excess of 30 % in the solutions, corresponding to a final film composition of Pb1,10Zr0,53Ti0,47O3.
© EDP Sciences 1998