Silicon-induced faceting of vicinal GaAs(001)

Abstract

This article presents in situ x-ray diffraction studies of the evolution of the morphology of 0.5°-miscut vicinal GaAs(001) surfaces during and following undoped and silicon-doped growth using organometallic vapor-phase epitaxy. Undoped growth leads to ordered monolayer steps. However, growth in the presence of silicon destabilizes this surface morphology and triggers faceting. Coarsening of the facet size proceeds even after the growth has stopped and results in large singular regions of GaAs(001) surface separated by step bunches. Dosing the surface with silicon without growing material does not trigger faceting. Growth of undoped GaAs on faceted surfaces recovers the initial state of ordered monolayer steps.