Microstructural Characterization of Epitaxial GaAs on Separation-by-Implanted- Oxygen Substrates

The direct growth of GaAs by molecular-beam epitaxy on separation-by-implanted-oxygen substrates is demonstrated. Cross-sectional transmission electron microscopy, Rutherford backscattering and channeling techniques have been employed to characterize these layers. Microtwins and threading dislocation are the predominant defects in the layers. Most of the misfit dislocation are confined within the GaAs and Si interface region by forming a type of edge dislocation.