Quasi-static and nonquasi-static compact mosfet models based on symmetric linearization of the bulk and inversion charges

Abstract

A particularly simple form of the charge-sheet model (CSM) is developed using symmetric linearization of the bulk charge as a function of the surface potential. The new formulation is verified by comparison with the original form of the CSM and is used to obtain a simple and accurate expressions for the quasi-static (QS) terminal charges based on the Ward-Dutton partition. Combined with the spline collocation version of the weighted residuals method, symmetric linearization leads to a relatively simple version of the nonquasi-static (NQS) MOSFET model. The efficiency of the proposed approach to MOSFET modeling is enhanced by taking advantage of the recently developed noniterative algorithm for computing surface potential as a function of the terminal voltages. An important symmetry of the various MOSFET characteristics with respect to the source/drain interchange is preserved in both the QS and NQS versions of the symmetrically linearized CSM.