Nanoscale triple-gate FinFET design considerations based on an analytical model of short-channel effects

Abstract

In this paper, a three-dimensional (3-D) analytical model for short-channel effects (SCEs) in a nanoscale triple-gate (TG) FinFET is derived based on solving a boundary value problem using the 3-D Poisson's equation. This model is validated using 3-D numerical simulations (TCAD Sentaurus). Results show that SCEs in a TG FinFET can be controlled by reducing either the fin thickness ( D ) or height ( H ). On the other hand, when fixing the drive capability of turn-on current, i.e. fixing the total width of the conductive channel, and changing the ratio of D and H , there exists a case where SCEs are worst, and SCEs can be reduced by either increasing or decreasing the ratio from the worst case. This SCEs model can be used to predict the minimum channel length ( L min ) of a device when D , H , and tox are fixed, while keeping SCEs at a tolerable level. Based on the analytical model, the insights into the physics of SCEs in nanoscale TG FinFET are discussed, and design considerations are investigated.