Initial growth of Ga2O3(Gd2O3) on GaAs: Key to the attainment of a low interfacial density of states
17 January 2000
Growth of the first few layers of an oxide mixture Ga2O3(Gd2O3) on GaAs (100) substrate, electron-beam evaporated from a Ga(5)Go(3)O(12) source, was found to be a single crystal. Reflection high-energy electron diffraction and x-ray diffraction studies show that the thin oxide film is epitaxially grown on GaAs with the surface normal (110) and in-plane axis {[}001] parallel to (100) and {[}011] of GaAs, respectively, and has a structure isomorphic to Mn2O3. Studies using high-resolution transmission electron microscopy on the oxide-GaAs interface indicate some atomic registry between the oxide and GaAs during the initial growth. The chemical composition of the oxide film was determined by x-ray photoelectron spectroscopy to be unequivocally pure Gd2O3. (C) 2000 American Institute of Physics. {[}S0003-6951(00)04503-4].