Enhancing Threshold Switching Characteristics and Stability of Vanadium Oxide-Based Selector With Vanadium Electrode

In this study, vanadium (V) was used as a top electrode in a vanadium oxide (VO_x)-based selector device. Electroforming was performed to form a threshold region with metal-insulator transition (MIT) at both V electrode and VO_x switching layers without annealing during fabrication. The simple V/VO_x/TiN structure obtained was scalable and compatible with complementary metal-oxide-semiconductors. All electrical measurement results indicated that V/VO_x/TiN selectors exhibited excellent characteristics such as high uniformity, a short switching time of 60 ns, a robust endurance of >10⁹ cycles, and high reliability and stability. Both the simulation analysis and current fitting method were applied to further validate experimental results. Consequently, we developed a nanoscale V/VOx/TiN selector with excellent characteristics, which can be potentially applied to future highdensity crossbar memory devices to overcome sneak-path problems.