Electrical transport and resistance switching characteristics of BiFeO3/Nb:SrTiO3/GaAs heterostructure fabricated by pulsed laser deposition

摘要

BiFeO3 thin films were epitaxially grown on (001) GaAs substrate by pulsed laser deposition with Nb doped SrTiO3 as a buffer layer. Piezoresponse force microscopy images exhibit effective ferroelectric switching of the heterostructure. The temperature-dependent current-voltage characteristics of the heterostructure reveal a resistance switching phenomenon and diode-like behavior with a rectifying ratio of 2 x 10(2) at the applied voltage of +/- 13.4 V. The electrical transport mechanism in the heterostructure has been illustrated by constructing the energy band structure. In addition, the resistance switching behavior in the heterostructure could be explained by the polarization modulation of the depletion region at the interface of the semiconductor and the ferroelectric layers.