Etching-dependent reproducible memory switching in vertical SiO2 structures

Abstract

Vertical structures of SiO${}_2$ sandwiched between a top tungsten electrode and conducting non-metal substrate were fabricated by dry and wet etching methods. Both structures exhibit similar voltage-controlled memory behaviors, in which short voltage pulses (1 $\mu$s) can switch the devices between high- and low-impedance states. Through the comparison of current-voltage characteristics in structures made by different methods, filamentary conduction at the etched oxide edges is most consistent with the results, providing insights into similar behaviors in metal/SiO/metal systems. High ON/OFF ratios of over 10${}^4$ were demonstrated.

6 pages, 3 figures + 2 suppl. figures