Fabrication and characterization of extended arrays of Ag₂ S/Ag nanodot resistive switches

Well-ordered Ag₂ S/Ag nanodot arrays with a density of >60 Gbit/in.² have been fabricated by sputtering Ag on a silicon substrate using ultrathin porous anodic aluminum oxide membranes as shadow masks, followed by sulfurization treatment at room temperature. The morphology, microstructure, and electrical properties of the as-prepared nanodots were characterized by scanning electron microscopy, x-ray diffractometry, transmission electron microscopy, and conductive atomic force microscopy, respectively. Well-defined resistive switching behavior was observed in these nanodots, and the ON/OFF ratio was found to be higher than 10². The Ag₂ S/Ag nanodot arrays hold substantial promise for use as ultrahigh density nonvolatile memory devices.