Comparative study of memory-switching phenomena in phase change GeTe and Ge2Sb2Te5 nanowire devices

Differences in memory-switching behavior based on the reversible amorphous–crystalline transition in GeTe and Ge2Sb2Te5 nanowires devices are investigated in detail. Phase change nanowires were synthesized via bottom-up-based vapor transport method. Main device parameters for memory applications such as threshold switching voltage, programming curves, and writing/erasing currents were measured and analyzed. In addition, nanowire-thickness dependent electrical characteristics were measured and efficient lowering of switching power consumption in both GeTe and Ge2Sb2Te5 nanowires was observed. Such interesting memory-switching phenomena are compared and discussed in terms of structural, thermodynamic and electrical uniqueness of GeTe and Ge2Sb2Te5 materials.