Improved Buildup Model for Radiation-Induced Defects in MOSFET Isolation Oxides

Ionizing radiation induces defects in STI oxides in current MOSFETs. These defects may degrade the performance of the MOS circuit. Analytical models for the buildup of these defects during the radiation exposure are available in literature. In this paper, we show that the classical model used to estimate the buildup of TID-induced traps in MOSTs predicts inaccurate results at high radiation levels. We, further, introduce an improved model to estimate the buildup of defects that is valid for both low and high radiation doses. Our improved model is compared to published data showing its validity.