  As metal-oxide-semiconductor field-effect transistors (MOSFET) channel
lengths (Lg) are scaled to lengths shorter than Lg<8 nm source-drain tunneling
starts to become a major performance limiting factor. In this scenario a
heavier transport mass can be used to limit source-drain (S-D) tunneling.
Taking InAs and Si as examples, it is shown that different heavier transport
masses can be engineered using strain and crystal orientation engineering.
Full-band extended device atomistic quantum transport simulations are performed
for nanowire MOSFETs at Lg<8 nm in both ballistic and incoherent scattering
regimes. In conclusion, a heavier transport mass can indeed be advantageous in
improving ON state currents in ultra scaled nanowire MOSFETs.
