MODELING THE SUBTHRESHOLD SWING IN MOSFETS

This letter reports on the bias-dependence of the inverse subthreshold slope or subthreshold swing in MOSFET's. It is shown by calculations and verified by experiments that the subthreshold swing varies with ga te bias and exhibits a global minimum. The gate-source voltage for whi ch minimum subthreshold swing is reached, is linearly related to the v oltage at which moderate inversion starts. Influence of oxide thicknes s and temperature is investigated. The subthreshold swing is an import ant parameter in modeling the weak inversion regime, especially for hi gh-gain analog applications, imaging circuits, and low-voltage applica tions, Based on calculations of the subthreshold swing, we propose a n ew model for the diffusion component of the drain leakage current in M OSFET's. The model accurately predicts the temperature dependence of t he drain leakage current.