Characterization of GaAs grown by metalorganic chemical vapor deposition on Si‐on‐insulator

Epitaxial GaAs layers were grown by metalorganic chemical vapor deposition on Si‐on‐insulator structures formed by high dose oxygen implantation. The quality of the GaAs films was examined as a function of layer thickness (0.01–4 μm). The surface morphology, ion backscattering yield, x‐ray diffraction peak width, and Si implant activation efficiency all improve substantially with GaAs thickness. At a film thickness of 4 μm many of these properties are comparable to bulk GaAs, but some cracking of the epitaxial film is evident. Cross‐sectional transmission electron microscopy reveals an average defect density of ∼108 cm−2 in the GaAs layer, which is similar to the density in GaAs films grown directly on Si.