Implementation of Band-to-Band Tunneling Phenomena in a Multisubband Ensemble Monte Carlo Simulator: Application to Silicon TFETs

Abstract

TFETs are in the way to become an alternative to conventional MOSFETs due to the possibility of achieving low subthreshold swing (SS) combined with small OFF current levels which allows operation at low VDD. In this work, a non-local band–to–band tunneling (BTBT) model has been successfully implemented into a Multi-Subband Ensemble Monte Carlo (MSEMC) simulator and applied to ultra-scaled silicon-based n-type TFETs. We have considered two different criteria for the choice of the tunneling path followed by the carriers when crossing the potential barrier, which leads to different distributions of the generated electron-hole pairs. Subband discretization due to field–induced quantum confinement has been taken into account. TCAD simulations accounting for quantization effects are considered for comparison purposes providing very accurate agreement with MS-EMC results.