Radiation response of fully-depleted MOS transistors fabricated in SIMOX

Abstract

The total dose radiation response of radiation-resistant fully-depleted submicron n-MOS and p-MOS transistors fabricated in SIMOX is presented. The total ionizing dose radiation induced threshold voltage shifts under three different irradiation bias conditions, including the worst case (pass-gate) bias for n-MOS transistors are discussed. Total dose hard fully-depleted p-MOS transistors are experimentally demonstrated. The larger threshold voltage shifts of fully-depleted n-MOS transistors as compared to partially-depleted n-MOS transistors in an ionizing radiation environment are explained by a model coupling the radiation induced buried oxide charge to the top transistor.