The non-equilibrium Green's function (NEGF) simulation of nanoscale lightly doped drain and source double gate MOSFETs

Abstract

This paper discusses modeling and simulation of three structures that called double gate MOSFET (DG-MOSFET) and linearly doped double gate MOSFET (LD-DG-MOSFET) and lightly doped drain and source double gate MOSFET (LDDS-DG-MOSFET) at the quantum transport level, with the nonequilibrium Green's function (NEGF) method. We have proposed LDDS-DG-MOSFET structure instead DG-MOSFET and linearly doped double gate MOSFET (LD-DG-MOSFET) structures. Here we define and perform modeling and simulation of a new structure with a simple improvement of double gate MOSFET. It is lightly doped drain and source double gate MOSFET (LDDS-DG-MOSFET). LDDS-DG-MOSFET is a new structure with a simple improvement of double gate MOSFET (DG-MOSFET), by using lightly doped regions in the middle of the channel and the highly doped source and drain regions. In this comparison, at the LDDS-DG-MOSFET structure with LDDS regions between the source-channel and drain-channel we have different subband energy profile that shows the barriers at two sides of channel are both widened. This cause reduces the tunneling current. In this manner, a LDDS-DG-MOSFET with especially lightly doped drain and source regions proves a larger ON current (I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</sub> ).