Temperature-dependent Poole–Frenkel transport properties of the SrSnO3/Nb-doped SrTiO3 heterostructure

Abstract

All-perovskite oxide heterostructure of SrSnO3/Nb-doped SrTiO3 was fabricated by using the pulsed laser deposition method. Unusual transport properties of the interface between SrSnO3 and Nb-doped SrTiO3 have been investigated at temperatures from 100 to 300 K. A diodelike rectifying behavior has been demonstrated by the temperature-dependent current–voltage (IV) measurements. The forward current showed typical IV characteristics of p–n junctions or Schottky diodes and was perfectly fitted using the thermionic emission model. At the reverse bias, however, the temperature-dependent IV curves developed in the opposite direction, indicating the tunneling effects on the interface. The Poole–Frenkel emission was used to explain this electrical transport mechanism under the reverse voltages.