On the modelling of temperature dependence of subthreshold swing in MOSFETs down to cryogenic temperature

Abstract

A comprehensive analysis of the MOSFET subthreshold swing for a 2D subband with exponential band tail of states is first proposed. Then, a compact analytical expression for the subthreshold swing as a function of temperature is derived, well accounting for both its cryogenic temperature saturation and classical higher temperature increase. Moreover, a generalized subthreshold swing calculation applicable to the situation where the MOSFET drain current should be evaluated from the conductivity function within the Kubo-Greenwood formalism is developed.