Using spatially resolved cathodoluminescence spectroscopy, an investigation was made of the spatial luminescence distribution in a fully strained (In,Ga)N layer, in particular, its correlation with the distribution of threading dislocations. Regarding the impact of threading dislocations on the luminescence properties, it was clearly possible to distinguish between pure edge-type threading dislocations and threading dislocations with a screw component. At the positions of both types of threading dislocation, non-radiative recombination sinks were established. The radius for carrier capture was at least four times larger for threading dislocations with screw component as for pure edge-type threading dislocations. The large capture radius of the former was due to a spiral-like growth mode resulting in an increase in the In content in the center of the spiral domains in comparison to their periphery

Carrier Capture by Threading Dislocations in (In,Ga)N/GaN Heteroepitaxial Layers. U.Jahn, O.Brandt, E.Luna, X.Sun, H.Wang, D.S.Jiang, L.F.Bian, H.Yang: Physical Review B, 2010, 81[12], 125314