The results of photoluminescence and the high-resolution X-ray diffraction investigations of point and extended defects in strained InGaAs(N)Sb/GaAs quantum-well structures grown at 478 to 505C were presented. High-resolution X-ray diffraction studies prove a good quality of hetero-interfaces in all samples that was attributed to Sb-surfactant effect. The photoluminescence investigations showed that the increase of the growth temperature of N-containing quantum wells led to an increase of potential fluctuations in quantum well due to the increase of composition disorder. In the photoluminescence spectra an intense band caused by excitonic transitions related with N-related clusters in GaAs barriers was found. High-resolution X-ray diffraction mapping in symmetrical 004 reflections revealed the oscillation of interference picture in [110] direction around the normal to (100) surface known as a wiggle. The mapping indicated the formation of elastically coupled domains which were elongated in the [¯110] direction and were supposed to be caused by lateral composition modulations in the quantum well. It was proposed that a so-called wiggle explained by the change of slopes of crystallographic planes with the depth was the result of competition of 2 factors; a symmetry of the surface stress tensor and a symmetry of bulk elastic moduli of a substrate material.

Investigation of Defect Structure of InGaNAsSb/GaAs Quantum Wells. L.Borkovska, N.Korsunska, V.Kladko, T.Kryshtab, V.Kushnirenko, M.Slobodyan, O.Yefanov, Y.Venger, S.Johnson, Y.Sadofyev, Y.H.Zhang: Materials Science and Engineering C, 2007, 27[5-8], 1038-42