First-principles study on Ge<inf>1−x</inf>Sn<inf>x</inf>-Si core-shell nanowire transistors

Abstract

The compositional dependence of electronic band structure in relaxed and biaxially strained Ge _1-x Sn _x alloy is investigated with the first principles method. Based on energy band dispersion along the [100] crystal orientation, hole effective mass is extracted via parabolic line fit. Calculation results indicate Sn composition dependence of the hole effective mass for relaxed alloy is much less pronounced than biaxially strained alloy. And then the electronic structure of Ge _1-x Sn _x -Si core-shell nano wire along the [110] direction is studied from first-principles calculation.