Influence of 0.1–10 MeV neutron-induced SEUs on estimation of terrestrial SER in a nano-scale SRAM

The impact of 0.1–10 MeV neutron-induced single-event upsets (NSEUs) on terrestrial SER (soft error rate) prediction is analyzed for several broad spectrum neutron sources based on 0.1–200 MeV NSEU energetic-dependent cross-sectional data of a 40 nm SRAM. The results show that for test facilities with abundant <10 MeV neutrons, such as ISIS ChipIR, J-PARC BL10, CSNS Back-n, and CSNS BL09, the terrestrial SER is overestimated. The overestimation could reach 78%–287%. By reducing the cutoff energy (Emin) from 10 to 6 MeV, the overestimation can be decreased. However, the overestimation can still reach up to 164% in this case, significantly larger than the results reported by previous studies. By analyzing the contribution of neutrons in different energy bins to NSEUs, the discrepancy is proved to be attributed to the sensitivity of NSEUs to 0.1–1 MeV neutrons, along with the overpopulation of 0.1–1 MeV neutrons for certain test facilities, such as ISIS ChipIR and CSNS BL09. Therefore, it is necessary to take 0.1–1 MeV NSEU sensitivity into account when studying the prediction method using broad spectrum neutron sources.