Atomic force microscopy was used to determine the origin of a strong step source in micro-channel epitaxy. The resultant images showed that 2-dimensional nuclei were frequently generated at a stacking fault. It was found that the shape of the 2-dimensional nuclei was not circular, but bow-like; with a chord that coincided with the line of the stacking fault and was aligned in the <01l> direction. A large radius of curvature of its arc, and a large contact-angle with the stacking fault, permitted nucleation to occur at a very low critical supersaturation. As a result, 2-dimensional nucleation became a major source of supply of growth steps when stacking faults existed; even under a very low supersaturation.

Two-dimensional nucleation at stacking faults during InP microchannel epitaxy S.Naritsuka, Z.Yan, T.Nishinaga: Journal of Crystal Growth, 1999, 198-199[1-4], 1082-6