True Random Number Generator using Memcapacitor with Charge Trapping Layer

Abstract

In this study, we experimentally validate a true random number generator (TRNG) utilizing a memcapacitor with TiN/Al2O3/HfO2/SiO2/Si (TAHOS) flash stack. The memcapacitor, incorporating a charge trapping layer, generates a displacement current via charge-discharge operations, and the current can be adjusted depending on the device state. Leveraging the randomness inherent in each switching cycle, this device can serve as an entropy source for the TRNG circuit. The generated bitstream has achieved a 95% confidence level in autocorrelation tests and has successfully passed 15 statistical tests from the National Institute of Standards and Technology (NIST), confirming its randomness and independence. This demonstrates the potential for stable and reliable hardware-based information security and encryption technology.