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

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_on).