Twin‐fluid atomization spray pyrolysis (SP) has been investigated for the production of lead zirconate titanate (PZT) powders, using aqueous solutions of lead acetate and zirconium and titanium alkoxide precursor reagents. The particle size distribution of the PZT powder showed a d50 value of 0.3 μm, but with a small fraction of relatively large particles, several micrometers in size. Most particles were spherical but many of the largest particles, in the size range ca. 1–5 μm, were irregular. It was demonstrated that the morphology of the final PZT powder was controlled by decomposition processes occurring during the initial drying stages, at ≤200°C. A pyrochlore or fluorite‐type intermediate crystalline phase was present in the final powders, but when the maximum reactor temperature was raised, and/or when the levels of excess lead in the starting solutions were increased, the proportion of the desired perovskite phase increased. However, at the highest process temperatures studied, ∼900°C, small crystallites of another phase formed on the surface of the PZT particles; these were probably lead oxide carbonate particles. Overall, a starting solution composition containing around 5 mol% excess Pb, and a maximum reactor temperature of 800°C, were selected as offering the most suitable conditions for producing PZT (52/48) powder, with minimal secondary phases(s). Preliminary densification studies showed that the powders could be sintered at 1150°–1200°C to give pellets of 95%–96% theoretical density.

Advanced analytical transmission electron microscopy has been used to investigate microstructural evolution during pyrolysis in triol-based sol-gel thin films. At pyrolysis temperatures up to 300°C, the films remained amorphous; however, nanometer-sized precipitates were observed in films heat-treated up to 400°C for 10 min. Analytical transmission electron microscopy indicated that the precipitates were Pb-rich, as well as deficient in O, Ti, and Zr. Films pyrolyzed up to 500°C for 10 min were composed of a nanocrystalline pyrochlore phase; however, pores could be observed, situated in the same position as the nanometer-sized precipitates at 400°C. Face-centered cubic Pb-rich crystallites were also present on the surface of pyrolyzed films but absent in the fully crystallized films annealed at 650°C. A tentative mechanism is proposed to explain these observations.

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Integrated lead zirconate titanate thin films deposited on Pt/Ti/SiO 2 /Si substrates using a novel triol-based route were characterized using X-ray diffraction and transmission electron microscopy. Crack-free single-layer PZT films of up to 200 nm thick were prepared by triol-based sol-gel processing onto Pt/Ti/SiO 2 /Si substrates. Films ϳ75 nm thick exhibited a microstructure free of pores and second phase. As film thickness increased, film texture changed from {100} to {111} perovskite. Essentially, single-phase multilayer films could be prepared by the deposition and pyrolysis of several 75 nm layers, followed by a single crystallization step. The influence of heat-treatment schedule on the microstructure and orientation of the multilayer films is discussed. Comparison has been made between multilayer films prepared using the triol-based sol and an inverted mixing order/acetic acid-based sol.