Influence of layer interface parameters on dielectric characteristics of BSTO ferroelectric film planar capacitors

Ferroelectric BaxSr1-xTiO3 (BSTO) films were prepared on sapphire (r-cut) a nd MgO substrates using two preparation processes-RF sputtering and the sol -gel method. The structure of the fame and interfaces were investigated by middle energy ion back scattering combined with ion channelling. Planar cap acitors patterned on the film allowed the temperature dependence of capacit ance and voltage-capacitance characteristics (VCC) to be measured at a freq uency of 1 MHz The influence of some interface parameters (e.g. the presenc e of intermediate layers, structural ordering of the BSTO surface layer, th e type of film electrode) on dielectric characteristics, VCC hysteresis and tunability of the planar capacitors are discussed.