Nonpolar resistive switching in Mn-doped BiFeO_3 thin films by chemical solution deposition

摘要

Nanoscale Mn-doped BiFeO_3 (BFMO) films are prepared by chemical solution deposition on Pt/Ti/ SiO_2/Si substrates. Nonpolar nonvolatile resistive switching has been observed in Pt/BFMO/Pt structure. Analysis of the current-voltage relationship demonstrates that the space-charge-limited current conduction controlled by the localized traps should be of great importance to the resistance switching. X-ray photoelectron spectroscopy results suggest that the coexistence of Fe~(2+) and Fe~(3+) can be ascribed to the relatively oxygen vacancies. According to defect chemistry, the valence variation between Fe~(2+) and Fe~(3+) determined by the neutralization/ionization of oxygen vacancies is supposed to play a crucial role in conductive filament-related nonpolar resistive switching.