THE INFLUENCE OF SURFACTANTS ON GROWTH MODES IN MOLECULAR-BEAM EPITAXY - THE GROWTH OF GERMANIUM LAYERS ON SI(100)

Up to 30 nm thick Ge layers were grown on Si(100) by using Sb as a surfactant and were investigated by reflection high-energy electron diffraction, x-ray photoelectron spectroscopy, secondary ion mass spectroscopy, transmission electron microscopy, and confocal laserscan microscopy. The introduction of a surfactant alters the growth mode drastically from a three-dimensional clustering mechanism to a two-dimensional layer-by-layer growth. Smooth and strained Ge layers, with a thickness much larger then the critical thickness for commensurate growth, are achievable. The antimony monolayer mainly segregates on top of the grown germanium layer.