Structural Properties of (GaAs)1-x(Si2)x Layers on GaAs(100) Substrates Grown by Migration-Enhanced Epitaxy

Abstract
Epitaxial (GaAs)1-x (Si2) x alloy layers (0<x1-x (Si2) x layers indicated single-crystal zincblende structure with no evidence of phase separation throughout the entire compositional range. The lattice constant a 0 of the alloys was found to decrease linearly with increasing Si content from 0.56543 nm at x=0 to 0.5601 nm at x=0.25. Double crystal X-ray rocking curve measurements and cross-sectional transmission electron microscopy studies made on a 10 period (GaAs)0.80(Si2)0.20/GaAs strained-layer superlattice indicated sharp and abrupt interfaces of high crystalline quality.