Simulation of the effects of space charge and Schottky barriers on ferroelectric thin film capacitor using Landau Khalatnikov theory

The role of space charge induced in a ferroelectric thin film and the presence of Schottky barriers at the two electrode/film interfaces are studied by numerical simulation using Landau-Khalatnikov theory. In this work, the whole film is considered as the stacking of dipolar layers, each of which contains multilayers of perovskite cells. In the presence of a local electric field, the double-well thermodynamic potential of each layer is modified in an asymmetric manner. The local electric field distribution is determined both by the space charge and the boundary conditions imposed by the Schottky barrier heights. Asymmetric and skewed hysteresis loops are generated.