High-Performance Multilevel-Storage Cu-Doped SiO_x-Based Nonvolatile Resistance Memory Using Ion Bombardment Technique

Abstract

Multi-level-cell (MLC) operation of Cu-doped SiOx-based (SiOx:Cu-based) resistance random access memory (ReRAM) has been reported for the first time. For this study, we employed a novel ion bombardment-induced (IB-induced) SiOx:Cu switching layer (SL). Using modulation of SET-current compliance, we completed 2-bit-per-cell memory application. The MLC resistance switching process is described in detail. Owing to controllability of Cu source from advanced IB technique, the IB-induced SiOx:Cu SL shows good cell-to-cell uniformity of MLC resistance switching parameters, including operation voltages and resistance states. Additionally, the IB-induced TaN/SiOx:Cu/TaN ReRAM exhibits infinite potential for MLC operation, such as over 3 times differentiation space among memory states, robust resistance retention, and promising operation endurance properties. During frequent MLC resistance switching, moreover, the IB-induced SiOx:Cu-based device also has excellent single-cell uniformity of memory states due to IB-induced thin Cu filament.