A study was made of the photoluminescence deep emission, at about 845nm, which was observed from quantum wells. The insertion of thin GaP layers into the interfaces was found to be effective in suppressing the deep emission. The effects of the thin GaP interlayer were considered in detail, and time-resolved photoluminescence measurements revealed that this deep emission had a long decay time. The onset of the emission occurred at about 20ns after the incidence of a laser pulse at 77K, while the delay was absent at 300K. The results suggested that this deep emission was predominantly non-excitonic and could not be explained by band-to-band emission from a GaInAsP intermediate layer at the GaAs/GaInP interface. It was proposed here that the deep emission was more likely to be caused by an atomic configurational defect in the GaAs/GaInP interface.

T.Arai, K.Uchida, H.Tokunaga, K.Matsumoto: Materials Science Forum, 1995, 196-201, 539-42