PHOTOLUMINESCENCE FROM INAS QUANTUM DOTS ON GAAS(100)

Several samples of self-organized InAs quantum dots (QDs) with differe nt InAs deposition and an InGaAs quantum well on GaAs(100) were grown by Molecular Beam Epitaxy (MBE). The photoluminescence (PL) of QDs was measured in the temperature range from 79 K to room temperature. The temperature dependence of the PL peak energy is roughly the same as th at of InGaAs quantum wells and attributed to the temperature dependenc e of the band gap. The ratio of PL peak intensity from QDs to that fro m wetting layer increases with the increase of InAs deposition. It is attributed to the increase in QDs density and more photocarriers trans fer from wetting layer to QD. In the case of small InAs deposition, th e PL intensity from QDs increases with temperature increase in a certa in temperature range. It is also due to the carrier transfer from wett ing layer to QDs. The full width at half maximum (FWHM) of the QDs dec reases with temperature in a certain temperature range. This is attrib uted to the photocarrier transfer from small QDs to large ones by tunn eling. (C) 1998 Elsevier Science S.A.