Optimization of Semipolar GaInN/GaN Blue/Green Light Emitting Diodes on {11̄01} GaN Side Facets

Bluish-green semipolar GaInN/GaN light emitting diodes (LEDs) were investigated as possible candidates for high-brightness devices even in the long wavelength visible regime. To combine the high material quality known from c-GaN and the advantages of a reduced piezoelectric field, the LED structures were realized on the {11̄01} side facets of selectively grown GaN stripes with triangular cross section. Structural investigations using transmission electron microscopy, scanning electron microscopy, high resolution x-ray diffraction, and atomic force microscopy have been performed and could be related to the luminescence properties in photoluminescence and cathodoluminescence. The defect-related luminescence peaks at 3.3 eV and 3.42 eV typically observed in planar nonand semipolar GaN structures as fingerprints of prismatic and basal plane stacking faults, respectively, could be eliminated in our facet LED structures by optimized growth conditions.