  The influence of interface roughness scattering (IRS) on the performances of
silicon nanowire field-effect transistors (NWFETs) is numerically investigated
using a full 3D quantum transport simulator based on the atomistic sp3d5s*
tight-binding model. The interface between the silicon and the silicon dioxide
layers is generated in a real-space atomistic representation using an
experimentally derived autocovariance function (ACVF). The oxide layer is
modeled in the virtual crystal approximation (VCA) using fictitious SiO2 atoms.
<110>-oriented nanowires with different diameters and randomly generated
surface configurations are studied. The experimentally observed ON-current and
the threshold voltage is quantitatively captured by the simulation model. The
mobility reduction due to IRS is studied through a qualitative comparison of
the simulation results with the experimental results.
