Selective area metalorganic molecular-beam epitaxy of GaN and the growth of luminescent microcolumns on Si/SiO₂

GaN microcolumns were grown on Si/SiO2 wafers by selective-area metallorganic molecular beam epitaxy. Scanning electron microscopy (SEM) at low and high magnifications showed the morphology of the selective area growths in a stripe and at the stripe edge, respectively. SEM also provided a near cross section and hexagonal cross section plan view of the microcolumns. Cathodoluminescence spectroscopy provided images of the microcolumns in panchromatic mode, using 365 nm luminescence, and using 570 nm luminescence.