Laboratoire d'Etudes et de Recherche sur les Matériaux, UPRESA CNRS 6004, Institut des Sciences de la Matière et du Rayonnement, 6 Bd du Maréchal Juin, 14050 Caen Cedex, France
Abstract:
An AlN buffer layer grown on (0001) sapphire substrate by molecular beam epitaxy has been studied. It is found to be made of small grains having a common [0001] axis parallel to that of the substrate. Some grains are rotated around this axis and the angle rotation can reach 20° leading to a new epitaxial relationship (0001)sap//(0001)AlN and [11
0]AlN. A model for the atomic structure of one of these grain boundaries is proposed using high resolution electron microscopy and extensive image simulation.