A physics-based TCAD framework for NBTI

Abstract

A physics-based framework is incorporated in TCAD to model the primary mechanisms responsible for Negative Bias Temperature Instability (NBTI) in P channel High-K Metal Gate (HKMG) MOSFETs. Three underlying mechanisms are treated including interface trap generation-passivation via a Reaction-Diffusion (RD) model and its charge occupancy via an Activated Barrier Double Well Thermionic (ABDWT) model, hole trapping and de-trapping in pre-existing defects in the gate stack are modeled via an ABDWT model, and bulk trap generation-passivation is modeled via a Reaction-Diffusion-Drift (RDD) model. The framework is used to model measured NBTI time-kinetics for DC stress-recovery and various mixed DC-AC gate pulse segments for planar devices. Furthermore, the same framework is also used to test NBTI behavior in 3D FinFETs.