Relation between HCI-induced performance degradation and applications in a RISC processor

Die shrinking combined with the non-ideal scaling of voltage increases the probability of MOS transistors to encounter hot carrier injections (HCI). This failure mechanism causes a performance degradation of digital ICs. The evaluation of timing degradations becomes a must-have to ensure the expected time-to-market and IC lifetime early in the design flow. In this paper, we present a design/verification flow at front-end from which we accurately analyze the impact of instruction-set architecture on processor timings. We show results on a RISC processor named AntX and designed in a 40 nm TSMC technology. Using typical-case scenarios can increase the maximum operating frequency by 15% on average compared to a worst-case scenario, while considering the same lifetime. We also identify that the shift operations cause the highest timing degradations along the long processor paths.