Calculations of R(T) and I(V) characteristics of the n-doped BaTiO3 ceramics with PTCR properties

The electrical characteristics of the n-doped BaTiO3 ceramics at various temperatures were obtained by considering their coupled semiconductive and ferroelectric properties. The ferroelectric lattice was described by the Landau-Devonshire theory and the free electron system by a Double Barrier Schottky model. The resistivity-temperature R(T) and current-voltage I(V) characteristic curves were simulated for various model parameters. The present theoretical approach explains the R(T) behaviour in a large range of temperatures, including the ferro-para transition one.