Electron microscopic studies of annealed layers which had been grown by molecular beam epitaxy at 200C were used to monitor the growth of As precipitates. The Ostwald ripening kinetics were then used to deduce a migration enthalpy of 1.4eV for the diffusion-mediating defect. The predominant diffusion mechanism could thereby be identified, and the above value was attributed to the migration enthalpy of Ga vacancies (VGa); as had been well-established by other experiments. The present work indicated that the growth of As precipitates was driven by a supersaturation of VGa.

Rapid Thermal Annealing of Low-Temperature GaAs Layers. Z.Liliental-Weber, X.W.Lin, J.Washburn, W.Schaff: Applied Physics Letters, 1995, 66[16], 2086-8