A Comparative Analysis of 65nm CMOS SRAM and Commercial SRAMs in Security Vulnerability Evaluation

Abstract

We present a comparative analysis of a fabricated 65nm CMOS static random access memory (SRAM) chip and commercial SRAM chips in terms of security vulnerability. The security vulnerability is defined as the leakage of information due to the data imprinting effect of the SRAM. There are three main features in this evaluation. First, a complete security vulnerability evaluation flow is proposed to stress the SRAM chips for accelerating the negative-biased temperature-instability (NBTI) degradation, i.e. data imprinting effect, and hence to reveal the stored data of image. Second, the evaluation quantifies the percentage of revealed data, i.e. leakage of information for the comparison of tested SRAMs. Third, the image is reconstructed from the revealed data to illustrate the security vulnerabilities of tested SRAMs. We perform the security vulnerability evaluation on the 65nm CMOS SRAM chip and 4 commercial SRAM chips, namely Alliance, Lyontek, Cypress and AMIC under stressing of high voltage and high temperature. From the experimental results, the stored data is significantly revealed in the deep-submicron (≤90nm) CMOS SRAM chips, i.e. fabricated 65nm CMOS (16.1%), Alliance (16.2%) and Lyontek (21%). After reconstructing the images, they can be identified in the 65nm CMOS, Alliance, Lyontek SRAMs, but remain as random states in the Cypress and AMIC SRAMs.