Interface Defects in GaAs and GaAs-AlxGa1−xAs Grown on Ge

Abstract

ABSTRACTΣ=3 lateral twin boundaries and a Σ=19 boundary have been investigated by highresolution electron microscopy. The lateral twin boundary was produced by growth on single crystal (110) Ge substrate and was observed to facet parallel to the common (112) plane and the (111)/{115} planes. The Σ=19 boundary was grown on a bicrystal substrate and faceted parallel to the common {331} plane. In this case, convergent-beam electron diffraction was used to determine the polarity of the adjoining grains. A possible model for the atomic configuration is proposed for each of the observed boundaries. GaAs-AlxGa1−xAs heterolayers were grown on a (001) Ge substrates to examine the interaction of antiphase boundaries with heterojunctions.