Conductance quantization in oxygen-anion-migration-based resistive switching memory devices

Quantized conductance was observed in an anion-migration-based resistive switching memory cell with the structure of (Ti, Ta, W)/Ta2O5/Pt. The conductance of the cell varies stepwise in units of single atomic conductance (77.5 μS), which is responsible for the formation and annihilation of atomic scale filament built from oxygen vacancies in Ta2O5 film. The quantized conductance behavior can be modulated by voltage pulses as fast as 100 ns. The demonstration of conductance quantization in Ta2O5 based memory device would open the door for quantized multi-bit data storage of anion-migration-based resistive switching nonvolatile memories.