Nonvolatile resistive switching devices based on nanoscale metal/amorphous silicon/crystalline silicon junctions

M/a-Si:H/c-Si based nonvolatile resistive switching devices with active areas down to 50 nmx50 nm have been fabricated and explored. Close to 100% device yield was achieved without necessity of high voltage forming process. Both rectifying switching and non-rectifying switching were demonstrated in a controllable fashion. The potential for this structure as nanoscale nonvolatile memory devices was investigated in terms of scalability, retention time, endurance and switching speed. The device showed switching speed faster than 5 ns, endurance cycles more than 10(6) and retention time longer than 150 days without any degradation of stored data. The devices exhibit improved resistance switching ratio when scaled down.