Fabrication and Electric Properties of SrTiO3-δ/Nb-SrTiO3 Heterjunction
SrTiO3- (STO) thin film has been deposited epitaxially on the (100) oriented, 0.1 wt % Nb-doped SrTiO3 (NSTO) substrate using the pulsed laser deposition technique. The current-voltage (I-V) characteristics of STO/NSTO heterojunction at various temperatures had been measured. A rectifying behavior similar to conventional diodes was observed. For the forward bias, the conduction mechanism changes from Ohmic-like for the low bias voltages to space charge limited current for the high bias voltages. The results were explained by considering the band structures of the heterojunction and the role of space charge layer formed at the interface between STO and NSTO. Our results demonstrate that the interface formed between two oxide materials plays an important role on transport characters of the system and can lead to some potential applications in future microelectronic devices based on combination of two perovskite oxide materials.
Yansheng Yin and Xin Wang
M. C. Ni et al., "Fabrication and Electric Properties of SrTiO3-δ/Nb-SrTiO3 Heterjunction", Advanced Materials Research, Vols. 79-82, pp. 2159-2162, 2009