Partially coalesced GaN pyramidal structures are formed by metal-organic chemical vapor deposition using the epitaxial lateral overgrowth method. Spatially resolved optical characterization of these structures has been carried out using cathodoluminescence (CL) microscopy and spectroscopy. The coalesced region exhibits much stronger and more uniform luminescence than other regions of the sample. In addition, the emission from the coalesced region is blue-shifted, while that from the sidewalls is red-shifted, relative to broad area grown samples. The peak shift mechanism is discussed based on the CL temperature and power dependence and analysis of the confocal Raman scattering.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)