Analytical models of subthreshold current and swing of short-channel strained-Si (s-Si) on Silicon-Germanium-on-Insulator (SGOI) MOSFETs

In this paper, surface potential based analytical models of subthreshold current and subthreshold swing of the strained-Si (s-Si) on Silicon-Germanium-on-Insulator (SGOI) MOSFETs have been presented. The models are based on the solution of the 2D Poisson's equation in the fully depleted channel region by approximating the potential in vertical direction of the channel. The thus obtained potential distribution function has been employed in deriving the closed form expressions of subthreshold current and subthreshold swing. The subthreshold characteristics have been studied as a function of various device parameters such as Ge mole fraction (x), gate length (L-g), gate oxide thickness (t(f)) and channel thickness (t(s-Si)). The proposed analytical model results have been validated by comparing with the simulation data obtained by the 2D device simulator ATLAS (TM), from Silvaco. (C) 2013 Elsevier Ltd. All rights reserved.