Crystallographic dependence of OMVPE InGaAs/InP lateral growth on patterned (100) InP substrates prepared by wet etching

InP layers and InP/InGaAs structures were grown at 600 degreesC using OMVPE on non-planar wet-etch InP substrates with patterns aligned at various angles Theta within [010] and [01-1] as well as [001] and [0-11]. The patterns were 15-mum-high ordinary mesa-shaped ridges with the sidewall facet angle cr dependent on the alignment angle Theta. Within 0.5 degrees < <Theta> < 10<degrees>, the morphology of InP exhibited ledges running down the slope of the facet, which increased the surface roughness. For larger angles Theta, it exhibited different features. The nucleation of InGaAs proceeded through faceted trapezoidal features. This type of nucleation was not suppressed on the facets for 0.5 degrees < <Theta> < 10<degrees>. For larger Theta, the InGaAs morphology exhibited different features. (C) 2000 Elsevier Science B.V. All rights reserved.