The effect of an interfacial layer on the relaxation of CdMnTe/CdTe multiple quantum well structures on InSb substrates

CdMnTe/CdTe multiple quantum well structures on InSb substrates have been investigated by means of high-resolution x-ray diffraction and topography. Simulation of the high-resolution x-ray diffraction profiles provided evidence of an interfacial layer at the interface between the InSb substrate and CdTe buffer layer. The topographs reveal the presence of misfit dislocations only in the sample with a thicker interfacial layer. We show theoretically that an interfacial layer will significantly affect the critical thickness for misfit dislocation generation. We confirm experimentally that only the sample with the thicker interface layer exceeds the critical thickness.