Morphology and stress evolution of InAs QD grown and annealed in-situ at high temperature

The post growth annealing of InAs quantum dots (QDs) at relatively high temperature was investigated by an in-situ stress cantilever beam setup. For samples annealed at 500∘C, stress accumulated during QD formation relaxes below the value which was built-up during wetting-layer growth. AFM images taken at different annealing stages reveal that QDs ripen first and then dissolve within 10 min of annealing. These observations are explained by a combination of In desorption, especially at the beginning of annealing, and interdiffusion between Ga and In.