Fig. 1: Strain impact on the band structure.
From: Phonon-limited mobility for electrons and holes in highly-strained silicon
a Illustration of the deformation of the silicon conventional cell under an applied stress along the [100] crystal direction and the reciprocal space equipotential surface of the six electron-valleys (brown) with the lift of the degeneracy between the Δ2-valleys (red) and the Δ4-valleys (blue). b Impact on the extrema of the valence bands and conduction bands. The density of states (DOS) of the three valence bands and the two valleys are indicated next to the band structure. Dashed brown curves are used for the unstrained case. c Band edges variations of the Δ4-valleys (blue), Δ2-valleys (red), heavy-hole (HH) band (orange), light-hole (LH) band (dark green) and spin-orbit (SO) band (light green) with the strain with spin-orbit coupling taken into account (continuous line) and without (dashed line). The energy is scaled to the valence band maximum at zero strain while the band gap (Eg) is obtained from the energy difference between the band edges.
