Unusual Electrical Transport Characteristic of the SrSnO3/Nb-Doped SrTiO3 Heterostructure

An all-perovskite oxide heterostructure composed of SrSnO3/Nb-doped SrTiO3 was fabricated using the pulsed laser deposition method. In-plane and out-of-plane structural characterization films were analyzed by x-ray diffraction with θ-2θ scans φ scans. X-ray photoelectron spectroscopy measurement performed to check film’s composition. The electrical transport characteristic determined applying a dc bias across interface. Unusual properties interface between SrSnO3 Nb-doped investigated at temperatures from 100 300 K. A diodelike rectifying behavior observed in temperature-dependent current-voltage (IV) measurements. forward current showed typical IV characteristics p-n junctions or Schottky diodes, perfectly fitted thermionic emission model. Two regions different mechanism detected, boundary curve expressed ln I = -1.28V - 13. Under reverse bias, however, temperature- dependent curves revealed an unusual increase reverse-bias decreasing temperature, indicating tunneling effects Poole-Frenkel used explain this under voltages.