The effect of dislocations upon the room-temperature photoluminescence intensity in GaN films grown by molecular beam epitaxy was investigated. In order to determine both screw and edge dislocation densities, X-ray diffraction was used in conjunction with a geometrical model which related the width of the respective reflections to the polar and azimuthal orientational spread. There was no direct dependence of the emission efficiency on the density of either type of dislocation in the samples under investigation. It was concluded that dislocations were not the dominant non-radiative recombination centers for GaN grown by molecular beam epitaxy.

Photoluminescence Intensity of GaN Films with Widely Varying Dislocation Density. Y.J.Sun, O.Brandt, K.H.Ploog: Journal of Materials Research, 2003, 18[5], 1251-8