Polycrystalline piezoelectric lead-free Bi0.5Na0.5TiO3 (abbreviated as BNT) thin films were deposited on glass substrates by an optimized Sol-Gel process using the Electrospray technique. X-ray Diffraction (XRD) analysis showed that after heating the films at 650˚C for 1 hour, dense and well crystallized BNT films in the rhombohedral perovskite phase were formed. Polyhedral shaped primary particles, with an average size of approximately 200 nm and a smooth surface of 1.8 nm average roughness (Ra), were detected using AFM analysis. The deconvolution of Raman spectrum had confirmed our first results of XRD about the crystallization of BNT films due to the appearance of Raman peaks corresponding to the bending vibrations of Bi-O, Na-O and TiO6 bonds.
Synthesis and characterization of BNT thin films