Using binary resistors to achieve multilevel resistive switching in multilayer NiO/Pt nanowire arrays

Abstract

Reliable multilevel resistive switching in nanoscale cells is desirable for the wide adoption of resistive random access memory as the next-generation nonvolatile memory. We designed NiO-based cells in arrays of multilayered NiO/Pt nanowires to explore multilevel memory effects. Nonpolar resistive switching reproducibly occurs with significantly reduced switching voltages, narrow switching voltage distributions and a robust multilevel memory effect. A high resistance ratio (B10 5 ) between the highand low-resistance states in nanoscale cells enables stable multilevels that can be induced easily by a series of pulsed voltage. The existence of intermediate resistance states in NiO/Pt nanowire arrays can be well explained by the binary-resistor model combined with energy perturbations induced by the pulse voltage. We also verified that the conduction mechanism in multilayered NiO/Pt nanowires is dominated by the hopping of holes. Our bottom-up approach and proposed mechanism explain the controllable multilevel memory effect and facilitate sound device design to encourage their universal adoption.

Resistive switching phenomena: A review of statistical physics approaches

“…The second way to obtain multiple resistance states is by varying the interconnection inside the CFs. 155,[362][363][364][365][366][367] This is usually used in unipolar switching. Because the resistance of the cell is strongly dependent on the interconnection between the conducting regions inside the CFs, if we gradually vary the interconnections, we obtain multiple resistance values.…”

Deterministic Role of Concentration Surplus of Cation Vacancy over Anion Vacancy in Bipolar Memristive NiO

“…Actually, the electrical transport in NiO is dominated by hole carriers, generated by nickel vacancies with shallow defect levels, 23,24 but nickel vacancies are considered more immobile than oxygen vacancies. [27][28][29] So the bipolar memristive behaviors in NiO cannot be explained by the aforementioned model. Of late, with first-principles calculations, Oka et al 29 got the band structures of NiO with isolated nickel vacancy, isolated oxygen vacancy and paired nickel and oxygen vacancies, respectively.…”

Configurable Operational Amplifier Architectures Based on Oxide Resistive RAMs

“…RESET operation is achieved by applying a voltage difference across the cell lower than the threshold V RESET . To obtain intermediate ON and OFF states, programming can be done gradually by applying an increasing number of identical voltage pulses across the cell [17].…”