A Unified Continuous and Discrete Model for Double-Gate MOSFETs with Spatially Varying or Pulsed Doping Profiles
Journal
IEEE Journal of the Electron Devices Society
Journal Volume
5
Journal Issue
4
Pages
244-255
Date Issued
2017
Author(s)
Abstract
This paper presents a unified continuous and discrete model covering all device operating regions of double-gate MOSFETs for the first time. With a specific variable transformation method, the 1-D Poisson's equation in the Cartesian coordinate for double-gate MOSFETs is transformed into the corresponding form in the cylindrical coordinate. Such a transformed cylindrical Poisson's equation results in a simple algebraic equation, which correlates the (inversion-charge induced) surface potential to the field and allows the long-channel drain-current formula to be derived from the Pao-Sah integral. This model can be readily applied to predict the effects of both continuous and discrete doping variations. The short-channel-effect model is also developed by solving the 2-D Poisson's equation using the eigenfunction-expansion method. The accuracy of both long-channel and short-channel models is confirmed by the numerical calculations and TCAD simulations. ? 2013 IEEE.
Subjects
Drain current; Eigenvalues and eigenfunctions; Poisson equation; Cartesian coordinate; Cylindrical coordinates; discrete dopant variations; Double gate MOSFET; Eigenfunction expansion methods; Numerical calculation; Surface field; Variable transformation; MOSFET devices
Type
journal article