An investigation was made of the initial growth of GaAs films on Si(111) substrates via molecular beam epitaxy. The GaAs grew with the creation of high-quality grain boundaries at a size of about 100nm; with no dislocations being present during growth of up to 200nm. The quality was deduced from the sharpness of the full-width at half-maximum of X-ray rocking curves of (111) GaAs diffraction, and from cross-sectional transmission electron microscopic observations. At thicknesses of up to 100nm, the full-width at half-maximum agreed well with the values for a perfect crystal; as calculated on the basis of dynamic diffraction theory. This was closely related to bond-matching near to the interface between GaAs and Si in the (111) orientation. In addition to the growth of high-quality grain boundaries, the growth of associated areas which had poor-quality regions around them predominated when the thickness exceeded 300nm.

T.Yodo, M.Tamura: Journal of Crystal Growth, 1995, 154[1-2], 85-91