Combining GEANT4 and TIARA for Neutron Soft Error-Rate Prediction of 65 nm Flip-Flops

Experimental neutron characterizations of standard and radiation-hardened-by-design (RHBD) flip-flops (FFs) are compared to combined GEANT4 and TIARA simulations. Good agreement is found between experiment and simulation for both architectures exhibiting soft error-rate (SER) values ranging over more than two decades. In-depth analysis of TIARA simulation results demonstrates that different underlying mechanisms are at the origin of observed soft errors: neutron-silicon (n-Si) elastic scattering for standard 65 nm FF while multiproduct nuclear reactions are for the RHBD structure. Finally, TIARA simulation results for monoenergetic neutron sources and atmospheric-like (i.e., synthetic) neutron spectra are discussed together with their impact on SER.