Facet growth near to SiO2 mask edges, during metalorganic molecular beam epitaxy, was studied for various V/III ratios on (100) substrates with a 2 misorientation towards (110). It was found that, whereas ideal vertical layer growth occurred at high V/III ratios (even after 2 of growth), oblique (111) planes were kinetically favored near to mask edges at lower V/III ratios. The V/III ratio was a key parameter since it determined the facets with the lowest kinetically limited growth rate at the border of the growing layer. Also, the diffusion length of mobile adsorbed species, which explained the presence of additional features near to mask edges and corners, decreased with the V/III ratio. As well as inter-facet diffusion which was driven by concentration gradients between facets with differing growth rates, there was also evidence for the occurrence of anisotropic diffusion along [0¯11] on (100) InP. It was suggested that this was the cause of the fine surface ripples which were observed on one side, near to the SiO2 masks.

R.Matz, H.Heinecke, B.Baur, R.Primig, C.Cremer: Journal of Crystal Growth, 1993, 127[1-4], 230-6