Characterization of barrier heights in Nd0.7Sr0.3MnO3/Nb : SrTiO3 junctions with current-voltage characteristics

Barrier heights in heterojunctions composed of Nd0.7Sr0.3MnO3 and Nb doped SrTiO3 have been characterized with current-voltage characteristics by using various methods. It is revealed that an inappropriate assumption of the transport mechanism would usually lead to the underestimation of the barrier height. Provided that the transport mechanism is correctly identified the barrier height deduced with current-voltage characteristics could be in accordance with Anderson's model and typical internal photoemission results. It is suggested that for manganite-titanate heterojunctions introducing the ideality factor in the thermionic emission saturation current density equation might largely counteract the underestimation of the barrier height.