Epitaxy and stress of MgO/GaAs(001) heterostructures
Sprache des Titels:
We report on the preparation of epitaxial MgO film on GaAs(001) substrates by molecular beam epitaxy at growth temperature of 20?200?°C. Reflection high energy electron diffraction, x-ray diffraction, and high resolution transmission electron microscopy reveal the growth of ordered crystalline cubic MgO(001) film at ?200?°C with MgO(001) || GaAs(001) and a 4 : 3 lattice registry. The surface of the MgO films, characterized by atomic force microscopy, exhibits a root mean square roughness of only 0.5?nm. In situ stress measurements reveal tensile stress as low as 1.7?GPa for a growth temperature of 200?°C in good agreement with the calculated residual misfit strain.