The growth rate profiles adjacent to selective area masks were studied for InP, InGaAs and InGaAsP by metalorganic vapour-phase epitaxy. Time-proportional growth rate increments were found for InP growth at the mask edge. The growth rate of InP at the edge saturated after the length of (111)B plane became larger than 1.4μm, which corresponded to the migration length of an In precursor on this plane. The time evolution of the InP layer at the mask edge was modelled as precursors stuck on (111)B plane which migrated to the (100) plane and diffused on that plane as well as being incorporated there. The simulated thickness of InP layers at the mask edge exhibited excellent agreement with experimental data. In the case of InGaAs and InGaAsP, there were no indications of surface diffusion in the thickness profile. However, the distribution of the photoluminescence wavelength of InGaAsP layers suggested that surface diffusion of Ga precursor on the (100) plane of the InGaAsP layer existed, with a diffusion length of as much as 8μm.

Vapor Phase Diffusion and Surface Diffusion Combined Model for InGaAsP Selective Area Metal–Organic Vapor Phase Epitaxy. T.Shioda, M.Sugiyama, Y.Shimogaki, Y.Nakano: Journal of Crystal Growth, 2007, 298, 37-40