Phase evolution of sol–gel prepared Pb(Zr0.3Ti0.7)O3 thin films deposited on IrO2/TiO2/SiO2/Si electrodes

We report on the microstructural analyses, by means of X-ray diffraction (XRD), scanning electron microscopy combined with energy dispersive X-ray analysis (SEM-EDX) and cross-section transmission electron microscopy (X-TEM), of chemically prepared Pb(Zr 0.3 Ti 0.7 )O 3 thin films deposited on IrO 2 substrates. The purpose of this study is to detail temperature and time dependence of the lead zirconate titanate (PZT) film microstructure on this type of conductive oxide substrate, partly through a comparison with identically processed PZT films deposited on Pt substrates. It was observed that PZT 30/70 films on IrO 2 bottom electrodes, fired at temperatures up to 620 °C, are not single phase, due to extensive lead losses during the processing. The IrO 2 substrate was found to be indirectly responsible for these losses. Nevertheless, good ferroelectric properties were measured ( P r was 50 μC/cm 2 for the 620 °C film). Based on the observed morphology and texture with increasing annealing time, a mechanism for phase evolution in sol–gel-derived PZT 30/70 films on IrO 2 substrates is proposed.