This paper reports a simulation study investigating
the drive current of a prototypical SiGe n-type FinFET built
on a relaxed SiGe substrate for different values of the Ge
content x in the Si(1−x)Gex active layer. To this purpose, we
performed strain simulations, band-structure calculations, and
multisubband Monte Carlo transport simulations accounting for
the effects of the Ge content on both the band-structure and the scattering rates in the transistor channel. Our results suggest that the largest on-current may be obtained with a simple Si active layer, because of the beneficial strain induced by the SiGe substrate. A SiGe channel instead is less performing because of strain relaxation and alloy scattering.
