Total Ionizing Dose Effects in FDSOI Compact Model for IC Design

Abstract

The total ionizing dose (TID) is a well-known reliability issue for integrated circuits (ICs). It consists in changes of MOSFETs dc characteristics following the irradiation of devices in a given radiative environment, such as space environment. TID effects have been investigated from an experimental and theoretical standpoint, and the compact modeling of TID effects has been included into BULK transistor compact models using PSP formalism in the case of uniform and nonuniform energetic distributions of interface traps. However, TID effects are still not included in fully depleted SOI (FDSOI) standard models. In this paper, TID effects modeling is proposed and included in Leti-UTSOI compact model for FDSOI MOSFETs. This model takes both uniform and nonuniform energetic distributions of both gate oxide/silicon and silicon/buried oxide (BOX) interface traps into account, as well as the contribution of oxide/BOX-trapped charges. Validation of the model has been done through TCAD simulations, and we used this model to extract TID parameters from the experimental data.