Physical modeling of ferroelectric tunnel junctions

Performance study of ferroelectric tunnel junctions (FTJ) entails the calculations of both the electrostatics of such structures and the electron transport through the ferroelectric barrier. We carried out these calculations with the tools developed in Comsol Multiphysics package for the asymmetric Pt/BaTiO3/SrRuO3 FTJ. In the linear regime we have found that tunnel electroresistance ratio increases steadily with the barrier thickness, reaching values greater than 400 for 5 nm barrier thickness. For larger barrier widths, tunneling contribution to conduction decreases and other mechanisms may become dominant.