Preparation of PZT thin films on Hastelloy substrate using sol-gel processing

Ferroelectric PZT thin films have been successfully coated on Si substrates using sol-gel technology for sensing applications. However little work pertinent to PZT film coating on metallic substrates has been reported. Hastelloy has good high temperature oxidation resistance, good electrical conductivity, and high mechanical strength. Due to these excellent properties, Hastelloy was chosen as a substrate material for sol-gel derived PZT film for sensing applications. However, the PZT precursor reacted with Hastelloy, inhibiting the formation of PZT perovskite structure. A thin intermediate layer was therefore introduced as a reaction barrier layer to reduce the extent of Hastelloy substrate-precursor solution reaction. Results showed that the reaction barrier layer significantly reduced the reaction. Thus the PZT films with the perovskite structure, were successfully formed on the Hastelloy substrate. X-ray diffraction analysis was conducted to study the effect of using reaction barrier layers on the film structure.