A High-Speed True Random Number Generator Based on Unified Selector-RRAM

In this letter, we propose and experimentally demonstrate a high-speed true random number generator (TRNG) by exploiting the probabilistic delay time of threshold switching (TS) in a unified selector-resistive random access memory (RRAM). The device consists of dual functional layers (VO2/HfOx) and exhibits high endurance and fast switching speed, enabling a high bit generation rate (>28M/s). The switching parameters have been comprehensively investigated to obtain a stable and fine entropy. The generated bitstream successfully passes 12 National Institute of Standards and Technology (NIST) statistical tests without any postprocessing. The randomness and independence of the entropy source are justified by the autocorrelation test at a 95% confidence level, demonstrating great potential in high-performance hardware security and stochastic computing implementations.