Threshold switching stabilization of NbO₂ films via nanoscale devices

The stabilization of the threshold switching characteristics memristive NbOx is examined as a function sample growth and device characteristics. Sub-stoichiometric Nb2O5 was deposited via magnetron sputtering patterned in nanoscale (50×50–170×170nm2) W/Ir/NbOx/TiN devices microscale (2×2–15×15μm2) crossbar Au/Ru/NbOx/Pt devices. Annealing at 700 °C removed need for electroforming smallest showed large asymmetry IV curves positive negative bias that switched to symmetric behavior larger Electroforming created conducting NbO2 filaments with whose did not change area increased. largest voltages most stable switching. As increased, resistance scaled R∝A−1, indicating crystallized bulk device. When size comparable filaments, annealed similar electrical responses electroformed devices, filament-like even without electroforming. Finally, addition up 1.8% Ti dopant into films improve or stabilize