DEPTH RESOLVED INVESTIGATIONS OF THE RELAXATION BEHAVIOR IN STRAINED GAINAS GAAS SUPERLATTICES USING GRAZING-INCIDENCE X-RAY-DIFFRACTION/

Strained and partially relaxed superlattices (SL) of GaInAs/GaAs super lattices (SLs) were grown on GaAs[001] by MBE. The thickness of the Ga 0.8In0.2As layers (t(a) = 18 nm) within the SL was smaller than the cr itical thickness for relaxation which is known for single layers on Ga As substrate. The total thickness of the SLs were constant (400 nm). T he thicknesses of the GaAs barriers were tb = 2, 16 and 30 Mn. All the samples were partially relaxed. The misfit dislocation are not unifor mly distributed. High concentration of defects were obtained near the film to substrate interface. Within the film microcrystallites are sur rounded by a network of misfit dislocations. The width of their orient ational distribution and the diameter of domains scale with the degree of relaxation. The different density of misfit dislocations which was found along the (110) and (-1, 1, 0) glide planes of low relaxed syst ems may be due to a monoclinic deformation of the film.