CHARACTERISTICS OF GAN STRIPES GROWN BY SELECTIVE-AREA METALORGANIC CHEMICAL-VAPOR-DEPOSITION

We report on the selective-area metalorganic chemical vapor deposition of GaN stripes in the size range of 50 to 125 mu m and the characteri zation of the morphology, topography, and optical properties of these stripes. GaN films (similar to 1-3 mu m) grown on (0001) sapphire are used as the substrates. Excellent surface morphology is achieved under optimized growth conditions which include a higher V/III ratio than b road area growth. It is found that, under certain growth conditions, ( 0001) terraces of similar to 5 mu m in width develop at the edges of a ll stripes, independent of stripe size and orientation. The selectivel y grown GaN yields stronger band-edge emission than the ''substrate'' GaN which indicates an improvement in optical quality. However, the do nor-acceptor pair recombination (or conduction band to acceptor transi tion) and yellow emission are also enhanced in certain areas of the st ripes, The spatial correlation of these emission bands is established by cathodoluminescence wavelength imaging, and the origin of these emi ssions is speculated.