Fabrication and characterization of high curie temperature BiSc1/2Fe1/2O3–PbTiO3 piezoelectric films by a sol–gel process

(1 − x)BiSc1/2Fe1/2O3–xPbTiO3 (BSF–PT) thin films with the composition of x = 0.45–0.6 were fabricated on the Pt(1 1 1)/Ti/SiO2/Si substrates via an aqueous sol–gel method. The structure and electric properties of these BSF–PT thin films were investigated. The films showed a maximum dielectric and piezoelectric activities for x = 0.55 which was around the morphotropic phase boundary (MPB) composition in BFS–PT ceramics. The local effective piezoelectric coefficient d33* of the BSF–PT film for x = 0.55 was approximately 50 pm/V, which was comparable to that of the BiScO3–PbTiO3 (BSPT) thin films, and the curie temperature was about 420 °C, also similar to that of BSPT films, but higher than that of PZT thin films. Therefore, the relative low cost of the BFS–PT films compared with that of BSPT films suggests potential device applications in high temperature.