Susceptibility of Group-IV and III-V Semiconductor-Based Electronics to Atmospheric Neutrons Explored by Geant4 Numerical Simulations

Abstract

New semiconductor materials are envisaged in numerous high-performance applica- tions for which the expected device or circuit performances cannot be achieved with silicon. In this context of growing use of new and specific semiconductors, the question of their susceptibility to natural radiation, primarily to atmospheric neutrons, is posed for high-reliability-level application domains. This numerical simulation work precisely examines nuclear events resulting from the interaction of atmospheric neutrons at the terrestrial level with a target layer composed of various group-IV and III-V semicon- ductor materials including silicon, germanium, silicon carbide, carbon-diamond, gal lium arsenide, and gallium nitride materials. Using extensive Geant4 simulations and in-depth data analysis, this study provides an accurate and fine comparison between the neutron interaction responses of these different semiconductors in terms of nuclear processes, recoil products, secondary ion production, and fragment energy distributions. Implications of these results on the rate of single-event transient effects at the device or circuit level are also discussed. alpha particles, characterized by lower LET values but longer ranges in the different semicon ductor materials, are susceptible to induce single events farther from their emission point than heavy fragments up to distances of hundred microns for alpha particles and several millimeters for protons. Finally, the consequences of neutron interactions in the different targets in terms of electron–hole pair generation, a fundamental mechanism at the origin of single events in electronics, have been examined. Our results show that germanium cor responds to the worst case and diamond (also SiC) to the best case with regard to e–h pair production, Si, GaAs, and GaN being relatively equivalent and of intermediate behavior with respect to this criterion.