Self-repairable, high-uniform conductive-bridge random access memory based on amorphous NbSe₂

Abstract

Conductive-bridge random access memory (CBRAM) emerges as a promising candidate for next-generation memory and storage device. However, CBRAMs are prone to degenerate and fail during electrochemical metallization processes. To address this issue, herein we propose a self-repairability strategy for CBRAMs. Amorphous NbSe₂ was designed as the resistive switching layer, with Cu and Au as the top and bottom electrodes, respectively. The NbSe₂ CBRAMs demonstrate exceptional cycle-to-cycle and device-to-device uniformity, with forming-free and compliance current-free resistive switching characteristics, low-operation voltage, and competitive endurance and retention performance. Most importantly, the self-repairable behavior is discovered for the first time in CBRAM. The device after failure can recover its performance to the initially normal state by operating with a slightly large reset voltage. The existence of Cu conductive filament and excellent controllability of Cu migration in the NbSe₂ switching layer has been revealed by a designed broken-down point approach, which is responsible for the self-repairable behavior of NbSe₂ CBRAMs. Our self-repairable and high-uniform amorphous NbSe₂ CBRAM may open the door to the development of memory and storage devices in the future.

Keywords

conductive-bridge random access memory / conductive filament / high uniformity / NbSe₂ / self-repairable

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