Determination of edge-component Burgers vector of threading dislocations in GaN crystal by using Raman mapping

摘要

The threading edge dislocations in a GaN crystal are analyzed via micro-Raman spectroscopy mapping. A clear contrast image of the E-2(H) peak shift from a higher wavenumber to a lower wavenumber is simulated. The direction from the higher-wavenumber region to the lower-wavenumber region is found to be in the 90 degrees rotation from the Burgers vector. The Burgers vector is experimentally determined to be a/3[11 (2) over bar0] using transmission electron microscopy. The magnitude of the Burgers vector agrees well between the simulated and experimental results. Thus, the density, direction, and magnitude of the edge component of the threading dislocations are identified using Raman spectroscopy mapping. (c) 2018 The Japan Society of Applied Physics