Preparation, basic physical properties, and possibilities of application of PZT-based thin films

摘要

Ferroelectric, polycrystalline thin films based on PZT-type solid solution were fabricated by the RF sputtering method. The chemical composition of the thin films was Pb(Zr_(0.53)Ti_(0.45)W_(0.5)Cd_(0.5)O_3) and it corresponded to the morphotropic region of the phase diagram of the PbZrO_3-PbTiO_3-PbW_(0.5)Cd_(0.5)O_3 solid solution. Homogeneity check and investigations of the thin film chemical composition were performed by X-ray microprobe analysis. It has been found that the thin films exhibit high homogeneity of the chemical composition and stoichiometry close to that of the target. The processing conditions diagram has been defined, which ensures conservation of stoichiometry of the chemical composition of the thin films. Experiments have shown that according to the conditions of the RF sputtering not only the perovskite-type crystalline structures are formed but also the pyrochlore-type structure, mixture of the perovskite and pyrochlore-type phases or the amorphous phase. The diagram showing clearly separated regions of processing parameters conductive to formation of these phases was determined. Dielectric and piezoelectric parameters of the thin films were also studied. Great application potential of the PZT-based thin films has been considered and possibility to employ as-obtained PZT thin films as active elements of the piezoelectric sensors has been reported.