Entropy source characterization in HfO2 RRAM for TRNG applications

In this work we perform an in-depth characterization of the entropy source available in Resistive RAM (RRAM) memory cells during the bit SET operation. We detail the motivation in using RRAM as an entropy source for TRNG. The main part of this article focuses on the entropy source characterization extracted from RRAM measurements and on the impact of different parameters (VSET and Rt). We also propose a method to select the most random bits and we evaluate the bit streams against the NIST test suites.