HIGH-RESOLUTION X-RAY CHARACTERIZATION OF LOW-TEMPERATURE GAAS AS SUPERLATTICE GROWN BY MOLECULAR-BEAM EPITAXY/

High-resolution x-ray analysis of Si delta-doped GaAs grown by molecul ar-beam epitaxy at a low substrate temperature (230-degrees-C) is pres ented. Superlattice satellite peaks in the rocking curve are observed for the sample annealed at 700-degrees-C for 10 min. The peak intensit y increases with increasing postgrowth annealing temperature and reach es the maximum value for the 900-degrees-C annealed sample. The evolut ion of the x-ray rocking curves can be explained consistently by the f ormation of a GaAs/As superlattice during the annealing period based o n the transmission electron microscope observations.