Structural modifications of the Gd2O3(110) films on GaAs(100)

We report an fee structure for the epitaxial Gd2O3 films grown on GaAs(100) . This fluorite-derived structure appears to be stabilized by epitaxy with the substrate and has a great similarity to the GaAs structure. A model cal culation supports this finding. Our secondary-electron imaging studies of t hese nanometer-thick films reveal that the films are cubic as deposited, an d this structure can be derived from the stable alpha -phase of the Gd2O3 b y a mild Ne+-ion bombardment and a subsequent anneal. These epitaxial Gd2O3 films have great importance because of their excellent surface passivation properties.