The model of non-radiative carrier recombination on threading dislocation cores was modified in order to estimate quantitatively the light-emission efficiency in GaN as a function of the dislocation density and non-equilibrium carrier concentration. The model predictions were in good agreement with available data on the minority carrier diffusion length in GaN. The dislocation density must be reduced, at least, down to ~107/cm2 in order to provide a light emission efficiency close to unity. The n-type background doping was found to be favorable for the further efficiency improvement.

Dislocation Effect on Light Emission Efficiency in Gallium Nitride. S.Y.Karpov, Y.N.Makarov: Applied Physics Letters, 2002, 81[25], 4721-3