Forming-free resistive switching characteristics in manganese oxide and hafnium oxide devices

Resistive switching properties of hafnium oxide and manganese oxide double-layer films sandwiched between Pt bottom electrode and Ag top electrode have been investigated. The devices exhibited bipolar resistive switching. As compared with the devices with hafnium oxide and manganese oxide single layer, the double-layered devices showed better resistive switching behaviors, including forming-free behavior, a high resistance ratio (>10(5-6) ), and good retention properties. The forming-free behavior of the bilayer device is very useful for resistive random access memory applications. The high resistance ratio is beneficial to distinguish the storage information. The formation and disruption of Ag conductive filament in the oxide layers led to the resistance changes. (C) 2019 The Japan Society of Applied Physics