Influence of the Surface Condition on the Thermal Relaxation of Strained SiGe Molecular Beam Epitaxy Layers

Abstract
Dependence of the thermal stability of Si1-x Ge x (x=0.23, 500 Å) layers on the surface conditions was studied. It was found that the samples with the surface oxide film or carbide were much stabler than as-grown MBE layers without any oxide or carbide for ∼800°C annealing. This result suggests that the thermal relaxation of the SiGe layers is greatly restrained by the surface oxide film or carbide, probably due to suppression of the introduction and/or propagation of dislocations by effects such as pinning at the surface.