Valence band offset at the Si/SiSn interface by applying deep level transient spectroscopy

摘要

A set of Si1-xSnx/Si(001) quantum wells (QWs) is grown by applying molecular beam epitaxy. The activation energies of holes in these QWs are studied by deep-level transient spectroscopy. It is observed that the holes activation energies increase monotonically with the Sn fraction (x). The valence band offset between pseudomorphic Si1-xSnx and Si obeys the dependence Delta E-v. = 1.69x eV, while the offset between the average valence bands of unstrained Si1-xSnx/Si heterojunction was deduced and obeys the dependence Delta E-vav = 1.27x eV.