Coexistence of Bipolar and Unipolar Resistive Switching Behaviors in a Pt∕TiO[sub 2]∕Pt Stack

Abstract

Bipolar resistive switching (BRS) as well as unipolar resistive switching (URS) behaviors in Pt/27 nm thick TiO 2 /Pt stacks were investigated. Depending on the current compliance during the electroforming process, either BRS or URS was observed. With a lower current compliance (<0.1 mA) during electroforming, asymmetric current-voltage curves showing BRS were observed in the voltage range -1.6 to +1.1 V, while with a higher current compliance (1-10 mA) URS behavior was observed. Furthermore, the permanent transition from BRS to URS was investigated by applying a voltage with a higher current compliance (∼3 mA).