PZT‐based Thick Films and the Development of a Piezoelectric Pressure Sensor

A study has been carried out on the relationship between the composition, poling condition and piezoelectric properties of thick film layers. Pastes based on lead‐titanate‐zirconate (PZT) powders, with either PbO or a lead‐alumina‐silicate glass frit as binder, were prepared. Microstructure, electrical and mechanical properties were analysed. Processing and poling conditions modify these properties; then a wide latitude of opportunities is offered in the choice of ferroelectric/piezoelectric characteristics of the layers used as sensing elements for sensors. A pressure sensor was realised where a circular diaphragm of alumina supports two piezoelectric layers obtained by screen printing and firing a PZT/PbO‐based ferroelectric paste. The design and the performance characteristics are described.