Influence of GaAs(001) substrate misorientation towards ˆ111‰ on the optical properties of InxGa12xAs/GaAs
نویسندگان
چکیده
Local variations in the optical properties of thick In0.13Ga0.87As films grown on GaAs~001! substrates misoriented toward $111% planes have been studied with polarized and spectrally-resolved cathodoluminescence ~CL! imaging. The degree of anisotropic relaxation and density of dark line defects ~DLDs! in CL was found to depend on the choice of the substrate miscut orientation. An enhanced anisotropy in DLD density and strain relaxation was found for a misorientation towards ~111!A relative to that for a misorientation towards ~111!B . Local variations and spatial correlations in polarization anisotropy, band-gap energy shifts, luminescence efficiency, and defect-induced long-wavelength luminescence were examined. © 1995 American Vacuum Society.
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