Analysis of charge deposition and collection caused by low energy neutrons in a 25-nm bulk cmos technology

Neutron-induced single event upsets (SEUs) in a 25-nm NMOSFET are analyzed using PHYSERD simulation. We confirm that the secondary H and He ions dominate SEUs above the threshold energies of (n,p) and ({\rm n}, \alpha) reactions although the production cross sections for H and He ions are smaller than the elastic scattering cross sections below 20 MeV. The SEUs induced by secondary H and He ions are influenced strongly by the size of the interaction volume considered in the simulation because the ranges of H and He ions are much longer than those of elastic recoils.