Oxygen induced strain field homogenization in AlN nucleation layers and its impact on GaN grown by metal organic vapor phase epitaxy on sapphire: An x-ray diffraction study

and its impact on GaN grown by metal organic vapor phase epitaxy on sapphire: An x-ray diffraction study J. Bläsing, A. Krost, J. Hertkorn, F. Scholz, L. Kirste, A. Chuvilin, and U. Kaiser Institute of Experimental Physics, Otto-von-Guericke-University Magdeburg, Universitätsplatz 2, D-39016 Magdeburg, Germany Institute of Optoelectronics, Ulm University, Albert-Einstein-Allee 45, D-89081 Ulm, Germany Fraunhofer-Institute of Applied Solid State Physics, Tullastraße 72, D-79108 Freiburg, Germany Central Facility of Electron Microscopy, Ulm University, D-89069 Ulm, Germany