Low temperature sol gel deposition of PST (Pb(Sc_0.5Ta_0.5)O₃) thin films

PST (Pb_1+x(Sc_0.5Ta_0.5)O₃) thin films with different amounts of Pb excess (x=0.05 to 0.2) were deposited onto silicon (Si) substrates via a Sol Gel method. The spin-coated films were fired by different methods using different furnaces and characterised by X-ray diffraction (XRD) and scanning electron microscopic (SEM) observations. In order to deposit films at a low temperature, the effect of the composition (Pb excess amount) and firing methods on the crystallisation behaviour have been investigated. SEM observations showed that the fired films have a smooth morphology without any cracks or pores. From X-ray diffraction analyses, it was found that firing methods (furnaces used) have significant effects on crystallisation temperature. Hot plate firing enables the perovskite phase to form at a temperature as low as 520°C, while that phase appears at 700°C in tube furnace firing.