Hole Effective Mass of Strained Ge1-X Sn x Alloys P-Channel Quantum-Well MOSFETs on (001), (110), and (111) Ge Substrates

Abstract

The dependence of effective mass on Sn content, pseudomorphic strain, cap layer thickness, and substrate orientation is theoretically studied for Ge-cap/Ge1-x Sn x /Ge substrate p-channel MOSFETs through six-band k·p method. The Luttinger-like and deformation potential parameters were obtained from the fit of Ge1-x Sn x band structures by the empirical pseudopotential method. The valence band alignment is theoretically determined by the empirical pseudopotential method and the model-solid theory. The high Sn content and thin Ge-cap layer both result the small effective mass at zone center along channel direction of the first subband.