Coupled interfaces for misreading avoidance and write current reduction in passive crossbar memory

Abstract

Passive crossbar arrays of oxide-based memory elements hold the promise of high density and speed nonvolatile memory. However, realization of the expected paradigm has been hindered by a so-called misreading problem resulting from sneak paths in passive crossbar arrays. We introduce a resistive memory element consisting of two coupled interfaces in a metal/doped oxide/metal structure. The element avoids the misreading problem by the nonlinearity in current-voltage loops and significantly reduces the write current. The distinct device characteristics may also be applicable in programmable analog circuits and neuromorphic circuits.

Diode-less bilayer oxide (WOx–NbOx) device for cross-point resistive memory applications

“…Recently, a complementary RS cell [19] consisting of two anti-serial filamentary memory elements was introduced with impressive implications for bipolar RS applications. Similar works were also reported in the case of diode-less nano-scale ZrO x -HfO x RRAM devices [20] and coupling memristive interfaces in a Pt-Nbdoped SrTiO 3 -Cu structure [21]. Other strategies for bipolar RS cells are still in demand so that more bipolar RS materials can be included for the realization of passive crossbar arrays.…”

Direct evidences of filamentary resistive switching in Pt/Nb-doped SrTiO3 junctions

“…[3][4][5][6][7] The investigations on metal/oxide interfaces are significantly necessary to understand fundamental device physics and design RS devices of high performance. 8 Doped perovskite oxides make a wonderful playground to explore the RS effects at metal/oxide interfaces due to the available high-quality single-crystal materials and the emergent phenomena arising from the many-body interaction (in other words, strong electron correlation), 9 such as metal-insulator transition. Several proposed models based on Pr 0.7 Ca 0.3 MnO 3 , which is a representative perovskite oxide with emergent phenomena, include interfacial band bending induced metal-insulator transition, 10 charge trapping or detrapping effect, 11 electrochemical migration of oxygen vacancy, 12,13 electric modification of defect structures, 14 and interfacial oxide formation/dissociation.…”