TEM characterisation of PZT films prepared by a diol route on platinised silicon substrates

PZT (65/35) films were prepared using a diol route with 10 mol% excess Pb and deposited on Pt/Ti/SiO2/Si substrates. Samples were characterised using XRD and cross-sectional TEM/STEM in combination with EDX and EELS. Linescan and point analyses were used to investigate the interdiffusion of elements over nanometre length scales during film heat treatments. During annealing at ca. 500°C, significant diffusion of elements occurred which had a dramatic effect on the film characteristics; interdiffusion of Pb and Si were clearly evident and the diffusion and reaction of Pb with the Pt electrode resulted in the formation of a distinct PbPtx phase (x=3–4) at the film/Pt interface. Drastic interdiffusion of all elements except Zr was detected at higher temperatures; further diffusion of Pb to the underlying layers resulted in a Pb-deficient condition in the bulk film and the formation of a fluorite-type nanocrystalline phase.