Formation-free resistive switching in nanocrystalline tellurium oxide

Abstract

In this work, we report on the observation of resistive switching (RS) in the nanocrystalline tellurium oxide (TeO x ) in ITO/TeO x /Ag device configuration. The TeO x films grown in an O2/Ar environment have dominant β-TeO2 along with other polymorphs and amorphous TeO2. From the RS characteristics, it is suggestive that the β-TeO2 phase promotes the conductive filament formation across the highly insulating amorphous matrix. The memory device demonstrates bipolar RS with excellent endurance, retention and on–off ratio. The device also features formation-free switching with low set and reset voltage (0.6 V and −0.8 V respectively) and displays multilevel switching upon varying compliance current. Current-Voltage characterization clarifies the conduction path is indeed filamentary type. The result highlights that TeO x can be a prominent RS material for memory and brain-inspired computing devices.