Plastically relaxed GeSi films with the Ge fraction equal to 0.29–0.42 and thickness as large as 0.5μm were grown on Si(001) substrates using the low-temperature (350C) buffer Si layer and Sb as a surfactant. It was shown that introduction of Sb that smoothed the film surface at the stage of pseudomorphic growth lowered the density of threading dislocations in the plastically relaxed heterostructure by 1 to 1.5 orders of magnitude and also reduced the final roughness of the surface. A root-mean-square value of roughness smaller than 1nm was obtained for a film with a Ge content of 0.29 and a density of threading dislocations of about 106/cm2. It was assumed that the effect of surfactant was related to the fact that the activity of surface sources of dislocations was reduced in the presence of Sb.

Plastic Relaxation of GeSi/Si(001) Films Grown by Molecular-Beam Epitaxy in the Presence of the Sb Surfactant . Y.B.Bolkhovityanov, A.S.Deryabin, A.K.Gutakovskiĭ, A.V.Kolesnikov, L.V.Sokolov: Semiconductors, 2007, 41[10], 1234-9