On the long-wavelength optimization of highly strained InGaAs/GaAs quantum wells grown by metal-organic vapor-phase epitaxy

We have investigated the influence of the metal-organic vapor-phase epitaxy growth conditions on the long-wavelength optimization of InGaAs/GaAs quantum wells (QWs). It is found that the V/III ratio is a critical parameter for the in incorporation and wavelength extension, with a strong sensitivity even at very high values. Furthermore, it is noted that the exact crystallographic substrate surface orientation close to (001) may have a strong influence on the photoluminescence (PL) properties with a maximum PL wavelength for orientations within 0.01-0.03 degrees from (0 0 1). This is discussed in terms of changing interface morphology and growth modes with increasing misorientation. Finally, the application of antimony as surfactant is not found to have an improving effect on the layer integrity, whereas a slight extension of the emission wavelength indicates a small incorporation of antimony in the QWs. (C) 2008 Elsevier B.V. All rights reserved.