The contrast of dislocation perpendicular to the surface in the electron beam induced current mode in GaN films was studied by a computer simulation and was measured experimentally. It was shown that contrary to the case of traditional semiconductors, the profile width of dislocation EBIC contrast in the crystals with small diffusion length decreased with beam energy increasing. It was shown that the contrast decay with distance to a dislocation could not be used for the direct diffusion length measurements. Instead, to estimate the diffusion length value a comparison of total simulated dislocation profile with the experimental one should be used. The similar conclusion could be made for the dislocation contrast in the cathodoluminescence mode.

Profile of EBIC Dislocation Contrast in Semiconductors with Small Diffusion Length. E.B.Yakimov: Physica Status Solidi C, 2009, 6[8], 1983-6