Investigation and comparison of analog figures-of-merit for TFET and FinFET considering work-function variation

Abstract

This paper investigates and compares the impacts of metal-gate work-function variation on important analog figures-of-merit (FOMs) for TFET and FinFET devices using 3-D atomistic TCAD simulations. Our study indicates that, at 0.6 V supply voltage and 0.2 V gate-voltage overdrive, TFET exhibits superior variation immunity regarding transconductance to drain-current ratio (g(m)/I-DS), output resistance (R-out) and intrinsic gain, and comparable variability in g(m) and cutoff frequency (f(T)) as compared with the FinFET counterparts. In addition, how the correlations between pertinent parameters (e.g., g(m) and R-out) impact the variation immunity of important analog FOMs are analyzed. Our study may provide insights for low-voltage analog design using TFET/FinFET technologies. (C) 2014 Elsevier Ltd. All rights reserved.