Hysteretic current–voltage characteristics and resistance switching at an epitaxial oxide Schottky junction SrRuO3∕SrTi0.99Nb0.01O3

Transport properties have been studied for a perovskite heterojunction consisting of SrRuO3 (SRO) film epitaxially grown on SrTi0.99Nb0.01O3 (Nb:STO) substrate. The SRO/Nb:STO interface exhibits rectifying current–voltage (I–V) characteristics agreeing with those of a Schottky junction composed of a deep work-function metal (SRO) and an n-type semiconductor (Nb:STO). A hysteresis appears in the I–V characteristics, where high resistance and low resistance states are induced by reverse and forward bias stresses, respectively. The resistance switching is also triggered by applying short voltage pulses of 1μs–10ms duration.