Electrically active defects in epitaxial layers which had been grown onto Al2O3 by plasma-induced molecular-beam epitaxy were investigated by using the electron-beam induced-current technique. Dislocations in the layers exhibited a high recombination activity which was controlled by rather deep centers. Recombination defect densities could be significantly reduced by layer-structure engineering.

SEM-EBIC study of defects in epitaxial AlGaN layers G.N.Panin, O.V.Kononenko, V.N.Matveev, E.B.Yakimov, O.Ambacher: Solid State Phenomena, 1998, 63-64, 131-8