Diameter dependent threshold voltage modification of resistive state switching in organometallic single nanowire devices (diameter～10-100 nm)

摘要

Reversible electrical resistive state switching (ERSS) and memory effects have been investigated for a wide range of organometallic compounds and device configurations where the underlying mechanism is still not fully explored. We synthesized single nanowires (NWs) of organometallic charge transfer complexes between pre-fabricated electrodes with diameter (d) 10 = d = 100nm, and their ERSS properties have been systematically investigated at 300 K, encompassing versatile measurement techniques. The thinnest NW with d similar to 10 nm switched to its low resistive state with very low applied voltage. It appeared as metallic in the switched state as confirmed by its current-voltage characteristics and temperature (T) dependent resistivity for 100 = T = 300 K. Supported by a theoretically simulated model, we proposed a possible mechanism for the single metallic filament formation in an almost defect-free 10 nm wire in its switched state considering the migration of metal ions created by a strong electric field between two very closely spaced electrodes. We also experimentally demonstrated that the diameter dependence of the threshold voltage (V-th) for switching follows a power law (V-th alpha d(delta)) which is independent of the electrode configurations, measurement techniques and growth mechanism. The results explained the strategies to engineer the ERSS properties of single NW devices and might be beneficial for further research and development. Published by AIP Publishing.