Evolution of radiation-induced soft errors in FinFET SRAMs under process variations beyond 22nm

New CMOS technologies such as SOI or FinFET are expected to enhance SRAM radiation-induced soft error rates thanks to a reduction on the charge collected as the devices get smaller. In this work we analyze how the radiation hardening capabilities of SRAMs are affected when process variations are considered by simulating cells using a predictive FinFET technology. The results show that even if the average critical charge to which SRAM cells are vulnerable is enhanced by process variations, its widened spread leads to an increase of the soft error rate by more than 40% as the technology node is scaled down to 7nm.