Ga2O3: The origin of growth-induced oval defects in GaAs molecular beam epitaxy

Based on thermodynamic and other quantitative results, we show that the formation of growth-induced oval defects in GaAs molecular beam epitaxy originates from the decomposition of Ga2O3 in the Ga melt and the subsequent evaporation of the resultant suboxide Ga2O molecules. After landing on the epilayer surface, these suboxide species most likely combine to form Ga2O3 plus Ga atoms which then act as nucleation centers for the formation of oval defects.