A fully analytical continuous model for graded-channel SOI MOSFET for analog applications

Abstract

In this work an analytical model of Graded-Channel (GC) Silicon-On-Insulator (SOI) nMOSFETs is proposed for analog applications. The model is based on a series association of two conventional SOI nMOSFETs each representing one part of the GC SOI nMOSFET channel. From this assumption, we propose a current model that considers the GC SOI MOSFET as a conventional SOI transistor, represented by one part of the channel only, in which the drain voltage is modulated by the remaining part. The proposed model has been verified through the comparison between its results and experimental measurements, presenting a good agreement. Some important characteristics for analog circuits, such as transconductance and Early voltage, are compared between the model results and experimental curves.