Energy‐Dependent Proton‐Induced Single‐Event Upsets in 16‐nm Bulk FinFET D Flip‐Flops: Mechanisms and Layout Impacts

Fin field‐effect transistor (FinFET) technology offers superior power–performance–area–cost metrics compared to planar CMOS, making it increasingly critical for radiation‐intensive aerospace applications. Nevertheless, FinFETs remain susceptible to single‐event upsets (SEUs) induced by protons, the predominant component of galactic cosmic rays. This work investigates proton‐induced SEU responses in 16‐nm bulk FinFET D flip‐flops, focusing on energy dependence and layout impacts. Two circuits with identical schematics but different layouts are evaluated through proton irradiation and Geant4 simulations. Results show a pronounced energy dependence in the SEU cross section for both circuits. At low‐to‐mid energies, direct ionization prevails, with peak energy deposition occurring at the Bragg peak aligned with the sensitive volume. Ionization from recoil atoms generated by elastic scattering also contributes to the SEU cross section. At high energies, nuclear reactions dominate, where secondary particles trigger indirect ionization over broader areas, elevating SEU probability. Meanwhile, layout significantly influences SEU susceptibility. At low energies, circuit #2 exhibits a higher SEU threshold than circuit #1 due to extended interconnects that increase node capacitance. Conversely, charge sharing between physically adjacent transistors in circuit #2 amplifies SEUs under high‐energy proton irradiation. These findings inform radiation‐hardened‐by‐design strategies to enhance FinFET reliability in intelligent aerospace systems.