Anisotropy of electron mobility in arbitrarily oriented FinFETs

Abstract

We simulated the behavior of electron mobility and the effect of volume inversion in FinFETs with different surface (hkl) orientations and channel directions, using a Monte Carlo simulator. For each surface orientation, different channel directions were also considered. In the case of the (110) surface, a strong anisotropy of electron mobility with channel direction was seen: when the channel was in the (110)/<001> direction, electron mobility was 50% higher than in (110)/<1-10>, and was similar to the mobility for a (100)/<001> direction. This anisotropic behavior with channel orientation was not observed in the (100)-or (111)-surface orientations. The study with silicon thickness also revealed some interesting consequences of the volume inversion effect.