Bipolar Resistance Switching Characteristics of ZnO/Nb-Doped SrTiO₃ Heterojunctions

An electrical pulse induced resistance switching effect in ZnO/Nb-doped SrTiO₃ heterojunctions is reported. The current-voltage curves of these junctions show hysteresis. Multi-resistance states are realized by applying voltage pulses with different amplitudes, and the resistance switching effect is more remarkable at low temperatures. The junction capacitance decreases dramatically with increasing frequency. Analysis of the results suggests that the trapping-detrapping process plays an important role in the resistance switching effect.