Atomistic modeling of gate-all-around Si-nanowire field-effect transistors

We report atomistic simulations of the transport properties of Si-nanowire (SiNW) field-effect transistors. Results have been obtained within a self-consistent approach based on the nonequilibrium Green's function (NEGF) scheme in the density functional theory framework. We analyze in detail the operation of an ultrascaled SiNW channel device and study the characteristics and transfer characteristics behavior of,the device while varying several parameters including doping, gate and oxide lengths, and temperature. We focus our attention to the quantum capacitance of the SiNW and show that a well-tempered device design can be accomplished in this regime by choosing suitable doping profiles and gate contact parameters.