Resistive switching memory device with metal-oxide quantum dots on a graphene layer

Abstract

We demonstrate a one diode-one resistor (1D-1R) type resistive switching memory device consisting of single layered metal-oxide quantum dots (QDs) and a vertically inserted graphene layer between the SiO2 layers on an n(+)-Si substrate. Mono-layered graphene on the bottom SiO2 layer with a thickness of 50nm was capped by a 5nm thick SiO2 top barrier layer deposited by using an ultra-high vacuum sputter. The In2O3 QDs layer embedded in the 50nm thick biphenyltetracarboxylic dianhydride-phenylenediamine polymer layer was formed by a curing process using polyamic acid at 400 degrees C for 1h. The current values of the high and low resistance states for this 1D-1R device were measured to be about 3.32x10(-9) and 5.54x10(-9)A at a read bias of 1V, respectively. The ratio of each resistance after applying sweeping bias from +8 to -8V and from -8 to +8V appeared to be about 0.59 at 1V. This resistance switching could have originated from the migration of the O-2 ions by the redox chemical reaction in the polyimide and carrier charging effect of the QDs. This hybrid memory structure with In2O3 QDs and graphene layer has a strong possibility for application in next generation nonvolatile memory devices.