Microcathodoluminescence spectrum measurements, and electron beam-induced current imaging, of free-standing n-type samples (grown by hydride vapor phase epitaxy) were made. Dark-spot defects in plan-view electron beam induced current and microcathodoluminescence images, and dark-line defects in microcathodoluminescence images taken on the cleaved surface of the samples, were associated with dislocations. Microcathodoluminescence spectra measurements, performed in the vicinity of dislocations or in the matrix, did not reveal specific luminescence bands that could be attributed to dislocations. It was instead suggested that dislocation regions had a higher density of deep non-radiative traps.Microcathodoluminescence and Electron Beam Induced Current Observation of Dislocations in Free-Standing Thick n-GaN Sample Grown by Hydride Vapor Phase Epitaxy. A.Y.Polyakov, A.V.Govorkov, N.B.Smirnov, Z.Q.Fang, D.C.Look, S.S.Park, J.H.Han: Journal of Applied Physics, 2002, 92[9], 5238-40