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) and 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 capacitors patterned on the film allowed the temperature dependence of capacitance and voltage-capacitance characteristics (VCC) to be measured at a frequency of 1 MHz The influence of some interface parameters (e.g. the presence of intermediate layers, structural ordering of the BSTO surface layer, the type of film electrode) on dielectric characteristics, VCC hysteresis and tunability of the planar capacitors are discussed.