Abstract :
The dependence of the electrical properties of SrxBiyTa2O9 thin films on the (Bi/Sr ratio 1.6, 2.3, 2.8, 3.4) has been investigated. The SrxBiyTa2O9 ferroelectric thin films were synthesized on Pt/Ti/SiO2/Si substrates using the pulsed laser deposition method. Saturation polarization (Pst) and coercive field (2Ec) depend on the Bi/Sr ratio. Pst increases while Ec decreases with an increase in Bi/Sr ratio. Atomic Force Microscopy images show that the grain size grows with increasing Bi/Sr ratio. It is observed that the impedance behavior in SrxBiyTa2O9 thin film, conforms to the Constant Phase Element (CPE) model. It is believed that the diffuse charges at the grain boundary build up a surface polarization because the impedance behavior close to pure capacitor with grain size increased.
