Ge Distribution in Gen/Sim Strained-Layer Superlattices

Abstract
Ge n /Si m strained-layer superlattices (SLSs) grown by molecular beam epitaxy were investigated by the X-ray diffraction method. The diffraction intensities of Ge4/Si12 SLSs were analyzed with surface segregation models. It has been found that surface segregation does not involve 1 ML but 2-3 ML of the Ge top layer, and that the smearing decay length is about 4.5 ML.