We investigate the proton tolerance of fully depleted silicon-on-insulator (SOI) MOSFETs with H-gate and regular-gate structural configurations. For the front-gate characteristics, the H-gate does not show the edge leakage observed in the regular-gate transistor. An anomalous kink in the back-gate linear I/sub D/-V/sub GS/ characteristics of the fully depleted SOI nFETs has been observed at high radiation doses. This kink is attributed to charged traps generated in the bandgap at the buried oxide/silicon film interface during irradiation. Extensive two-dimensional simulations with MEDICI were used to understand the physical origin of this kink. We also report unusual self-annealing effects in the devices when they are cooled to liquid nitrogen temperature.

Fully depleted SOI MOSFETs show anomalous radiation effects, including kinks in back-gate linear I/sub D/-V/sub GS/ characteristics, and unusual self-annealing effects when cooled to liquid nitrogen temperature.

Anomalous radiation effects in fully depleted SOI MOSFETs fabricated on SIMOX

Key Takeaway: Fully depleted SOI MOSFETs show anomalous radiation effects, including kinks in back-gate linear I/sub D/-V/sub GS/ characteristics, and unusual self-annealing effects when cooled to liquid nitrogen temperature.