ROOM-TEMPERATURE LUMINESCENCE FROM SI GE SINGLE-QUANTUM-WELL DIODES GROWN BY MOLECULAR-BEAM EPITAXY/

Room-temperature electroluminescence (EL) in the near infrared (lambda approximate to 1.3 mu m) has been observed from Ge/Si/Ge/Si1-xGex qua ntum well (QW) diodes grown by molecular beam epitaxy (MBE). The QWs a re grown on a p(+)-doped [100]-Si substrates and consist of two thin G e wells separated by a thicker Si middle layer. The whole structure is embedded in Si0.85Ge0.15 alloy layers situated on both sides. The str ucture was designed by pseudopotential calculations with a view to ens uring stability of the interband luminescence up to room temperature. The observed spectra are in good agreement with our theoretical predic tions.