Strain relaxation in initially flat SiGe films on Si(100), during rapid thermal annealing, was studied. The surface roughened during high-temperature annealing, and this was attributed to intrinsic strain in the epilayers. It was noted that high-temperature annealing also resulted in a roughened interface; thus indicating the occurrence of preferential interdiffusion. It was suggested that the roughening at the surface made the intrinsic strain in the epilayer, as well as in the substrate, unequally distributed; causing preferential interdiffusion at the SiGe/Si interface during high-temperature annealing.

Strain-Induced Morphological Evolution and Preferential Interdiffusion in SiGe Epitaxial Film on Si(100) during High-Temperature Annealing J.P.Liu, M.Y.Kong, X.F.Liu, J.P.Li, D.D.Huang, L.X.Li, D.Z.Sun: Journal of Crystal Growth, 1999, 201-202, 556-9