Transmission electron microscopy structural investigations with atomic resolution were carried out on different rare earth doped GaN samples. Rare-earth doping was done by using 2 techniques: ion implantation on MOCVD substrates and in situ by molecular beam epitaxy. In both cases typical stacking faults were formed. They were shown to be correlated with possible rare-earth segregation.

The Atomic Structure of Defects Formed during Doping of GaN with Rare Earth Ions. T.Wojtowicz, P.Ruterana, K.Lorenz, U.Wahl, E.Alves, S.Ruffenach, G.Halambalakis, O.Briot: Physica Status Solidi C, 2005, 2[3], 1081-4