TCAD-моделирование нанометровых структур FinFET на объемном кремнии с уче-том воздействия радиации

Abstract

Transition from planar MOSFET structures to FinFET 3D structures ensures various radiation type resistance. However, the characteristics of radiation-exposed devices made at different factories vary considerably and it is hard to explain FinFET structures’ radiation resistance dependence on variations of their physical and topological parameters and electrical modes. In this work, a RAD-TCAD model of FinFET on bulk silicon was developed. Additional semi-empirical radiation dependences specific to FinFET structures were introduced into the basic model of a nanometer MOSFET: the charge carrier effective mobility, the traps concentration in the SiO2 and HfO2 oxides and at the Si / SiO2 interface. The model was implemented in the Sen-taurus Synopsys TCAD environment. The model was validated on a test set of FinFET structures with a channel length from 60 nm to 7 nm before and after exposure to gamma irradiation in the dose range up to 1 Mrad. Comparison of the modeled and experimental I-V characteristics has shown an error of no more than 15 %.