Impact of Radiation-Induced Back-Channel Leakage and Back-Gate Bias on Drain Current Transients of Thin-Gate-Oxide Partially Depleted Silicon-On-Insulator n-channel Metal–Oxide–Semiconductor Field-Effect Transistors

Abstract

In this study, we analyze the impact of back-channel radiation-induced leakage and back-gate bias on switch-off drain current transients of thin-gate-oxide partially depleted (PD) silicon-on-insulator (SOI) n-channel metal–oxide–semiconductor field-effect transistors (MOSFETs). The presence of radiation-induced positive trapped charges in the buried oxide after 60 MeV proton irradiation is found to reduce the “switch-off” transient times for gate voltages above and below the front-gate threshold voltage for body-to-gate electron valence band tunnelling. An increase in steady-state drain current and an increase in the amplitude of weak inversion drain current transients are observed. A similar effect is observed when applying a positive bias to the back-gate, which is found to generate an “irradiation-like” subthreshold leakage. The observed switch-off drain current transient behavior is explained by taking into account an edge parasitic back-channel transient component, which is added to the conventional front-gate drain current transient.