RELATIONSHIP BETWEEN SURFACE-MORPHOLOGY AND STRAIN RELAXATION DURING GROWTH OF INGAAS STRAINED LAYERS

The relationship between the surface morphology and strain relaxation is explored in strained InxGa1-xAs layers grown on GaAs by molecular b eam epitaxy. In situ light scattering, detected simultaneously along [ 110] and [1(1) over bar0$], reveals an asymmetric surface roughening w hich is consistent with ex situ scanning force microscopy. Transmissio n electron microscopy shows that strain relaxation by misfit dislocati on formation occurs before the surface roughening is detected, for In0 .18Ga0.82As films grown at 490 degrees C. (C) 1995 American Institute of Physics.