On the research of lead-free material challengers for PZT replacement

This paper reports a study of Ba0.9Sr0.1TiO3 and BaTi0.98Sn0.02O3 thin films elaborated by a sol–gel route and deposited on Pt/Ti/SiO2/Si substrates. The annealing temperatures were 750 °C, 850 °C and 950 °C. An increase of the average size of grains was observed, from 60 nm at 750 °C to 110 nm at 950 °C and from 70 nm at 750 °C to 150 nm at 950 °C, for BST and BTS respectively, as well as an increase of the dielectric constant and remnant polarization. We have also shown that there are benefits for electrical properties to decrease the annealing time. Despite its non-significant piezoelectric and ferroelectric properties, BTS gives good dielectric properties. Under our optimized annealing conditions, we gave the evidence that ferroelectric BST is a good challenger to replace PZT in various applications, except in piezoelectrics, as the electrical properties measured on our thin films were particularly significant for applications in electronic devices.

► Lead-free materials.
► BST, BTS thin films.
► Electrical properties.
► PZT replacement.