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

1. Introduction
2. Experiment
3. Results and Discussion
4. Conclusion

• De-Peng Wang(Graduate Student, School of Physics and Electronic Information, Yantai University, Yantai 264005, China)
• Rui-Feng Niu(Graduate Student, School of Physics and Electronic Information, Yantai University, Yantai 264005, China)
• Li-Qi Cui(Graduate Student, School of Physics and Electronic Information, Yantai University, Yantai 264005, China)
• Wei-Tian Wang(Professor, School of Physics and Electronic Information, Yantai University, Yantai 264005, China) Corresponding author