Effect of Oxidizable Electrode Material on Resistive Switching Characteristics of ZnOxS1-x Films

Abstract

We investigate the memory characteristics of ZnOxS1-x based resistive switching random access memory (ReRAM) devices with Al and Pt bottom electrodes (BEs). Both the ReRAM devices with Al and Pt BEs exhibit unipolar resistive switching behaviors, regardless of the materials of the BEs. The ratios of the high resistance state (HRS) to the low resistance state (LRS) of the Au/annealed ZnOxS1-x/AL and the Au/annealed ZnOxS1-x/Pt devices are more than 10(6) and 10(4), respectively. The HRS depends more significantly on the material of the BE than the LRS. The resistance in the HRS of the device with the Al BE is more stable in the endurance characteristics and higher in magnitude than that of the device with the Pt BE. For an anealed ZnOxS1-x/AL film, the oxygen signal in the auger depth profile shows the formation of an AlOx layer at the interface between the annealed ZnOxS1-x layer and the Al BE. The difference between the memory characteristics of the annealed ZnOxS1-x devices with the Al and Pt BEs is explained with the presence or absence of the oxidized layers formed in the interfaces between the annealed ZnOxS1-x films and the BEs.