The progress made in understanding the role played by threading dislocations in controlling the physical properties of this material and its alloys was reviewed. It was increasingly evident that threading dislocations in the group-III nitrides behaved as non-radiative recombination centres, had energy levels in the otherwise forbidden energy gap, acted as charged scattering centres in doped materials and provided a leakage-current pathway. When compared with conventional III-V semiconductors, the relatively small minority carrier diffusion length (some 50nm) in the III-nitrides - combined with favourable threading dislocation geometries - minimized dislocation-related degradation.

The Role of Threading Dislocations in the Physical Properties of GaN and its Alloys. J.S.Speck: Materials Science Forum, 2001, 353-356, 769-78