Zirconium tin titanate thin films via aqueous polymeric precursor route

Zirconium titanate-based thin films are considered as a promising dielectric material for the next generation of integrated microwave devices. The zirconium tin titanate (ZTS) precursor was prepared via a polymeric precursor process in aqueous phase, based on the citrate route. The presented chemical procedure is original for this kind of materials. C-13 nuclear magnetic resonance (NMR) spectra showed that stable mixed-metal chelate complex has been formed. The viscous resin was multiple spin-coated with intermediate firings at 300°C onto platinized Si substrates and fired in air at 700°C. Thin films 200-nm thick were obtained. Atomic force microscope (AFM) analysis showed that the coverage is homogeneous, the surface texture consisting of elongated grains of average size 20×36 nm. Grazing incidence X-ray diffraction analysis (GIXRD) indicated that only the zirconium tin titanate phase is present within the examined range of penetration depth.