An Equivalent Circuit Model for Ba0.5Sr0.5TiO3-Based Capacitors

In order to integrate a ferroelectric-based device into a larger circuit, one must create an equivalent circuit model for the device. Ferroelectric materials contain a number of complicated parameters that make this task far from trivial. In a Ba0.5Sr0.5TiO3-based capacitor, for example, the capacitance and leakage current vary with applied voltage, temperature and frequency. In addition, at high frequencies the equivalent series inductance and resistance (ESL and ESR) become non-negligible. All of these factors must be understood and quantified in order to create a working circuit. Such an analysis is reported for capacitors fabricated from Pt/BST/Pt films.