Surface morphology of InGaAs on GaAs(100) by chemical beam epitaxy using unprecracked monoethylarsine, triethylgallium and trimethylindium

Abstract

Temperature-dependent evolution of surface corrugation and the interface dislocation in In0.15Ga0.85As epilayer on GaAs(100) substrate grown by chemical beam epitaxy using unprecracked monoethylarsine have been investigated by atomic force microscope (AFM) and transmission electron microscopy (TEM). AFM images showed that the line direction of surface ridge changes from [011] to [0(1) over bar1$] with increasing temperature. However, TEM micrographs showed that dislocation networks are formed along both [011] and [0(1) over bar1$] directions at the interface. These results indicate that growth kinetics on the terrace and at surface steps generated by the dislocations play an important role in determining the direction of surface corrugation. We suggest that the temperature-dependent change of surface corrugation is caused by an anisotropic surface diffusion on the terrace and different sticking probability of adsorbates on the surface steps which were produced by interface misfit dislocation along the two orthogonal surface directions.