THERMAL-STABILITY CHARACTERIZATION OF DOPED LAYERS AND HETEROSTRUCTURES GROWN BY SI-MOLECULAR BEAM EPITAXY

The thermal stability of layers grown by Si-molecular beam epitaxy is reported in a comparative study of strain induced in Si by heavy B doping and by Si1-xGex alloying. High-resolution X-ray diffraction mapping was employed as the major analytical tool. The strain relaxation under high-temperature annealing is shown to be dominated by the formation of precipitates and by diffusion in the case of heavy doping but with a negligible amount of dislocations. In the Si1-xGex/Si heterostructures, the process is dominated by strain relaxation via formation of misfit dislocations.