Influence of layout structures to soft errors caused by higher-energy particles on 28/65 nm FDSOI flip-flops

The effects from layout structures of flip-flops for soft errors are investigated. Three flip-flops with different layouts but identical layout areas are fabricated in 28/65 nm FDSOI. Heavy ion irradiation by 40 MeV-cm
²
/mg reveals that the layout with separated diffusions in 28 nm have 2× cross section than that with shared diffusion. Flip-flops in 65 nm have almost equivalent cross sections at any energy. It is due to fluctuations of soft-error tolerance caused by layout structures of the highly-scaled 28 nm.