Epitaxial growth of γ - Al2O3 layers on Si(111) using Al solid source and N2O gas molecular beam epitaxy

High crystalline quality γ-Al2O3 films were epitaxially grown on Si(111) substrates at low growth temperatures from 750 to 900 °C by Al solid source and N2O gas molecular beam epitaxy. Very thin γ-Al2O3 films grown at 850 °C showed streaky reflection high-energy electron diffraction patterns. By in situ x-ray photoelectron spectroscopy measurements, carbon contamination, as is seen in the films grown with Al(CH3)3 source, was not detected within the sensitivity. The stoichiometry of the growth films was found to be similar to that of Al2O3. Growth rates of epitaxial γ-Al2O3 layers were found to decrease with increasing growth temperatures.