Overview of Resistive Random Access Memory (RRAM): Materials, Filament Mechanisms, Performance Optimization, and Prospects

Because conventional nonvolatile memory is limited by process technology and physical size, resistive random access memory (RRAM) gradually enters the field of view due to its simple structure, fast program/erase speed, low power consumption, and so on. This review article summarizes the materials, filament mechanisms, performance optimization, and application prospects of RRAM structures to provide readers with a reference for future investigation. The filament mechanisms, which involve the electrochemical metallization mechanism (ECM), valence change mechanism (VCM), and thermochemical mechanism (TCM), of RRAM devices are particularly highlighted. The parameters that determine the RRAM characteristics such as operating voltages, ON/OFF ratio, endurance, and data retention are improved by incorporating the three methods: 1) “interface engineering”, 2) element doping of functional materials, and 3) introduction of low‐dimensional materials. In the last section, a brief introduction to the future RRAM application prospects and challenges is provided.