Electroluminescence from Strained SiGe/Si Quantum Well Structures Grown by Solid Source Si Molecular Beam Epitaxy

Abstract
Electroluminescence (EL) is reported for Si0.8Ge0.2/Si quantum well (QW) structures grown by “solid source” Si molecular beam epitaxy for the first time. The spectral profile was dominated by SiGe quantum well emissions, no-phonon (NP) transitions due to symmetry-breaking SiGe alloy disordering and its transverse optical (TO) phonon replica. EL was observed from 27 up to 120 K. The integrated intensity was found to linearly increase with increasing injection current. Hole depopulation out of the quantized state was responsible for EL spectral variation at higher temperatures.