Red Emission of InGaN/GaN Double Heterostructures on GaN Nanopyramid Structures

We fabricated InGaN double-hetero structure (DHS) on the nanosized pyramid structure and successfully demonstrated efficient red color emission at 650 nm from this unique structure. The nanosized pyramid structure was fabricated by selective area growth method with nanoimprint. The different diffusion length of composite atoms and compositional pulling effect on the pyramid structure gave rise to not only compositional variation, but also high In-content InGaN of more than 40%. The InGaN DHS on nanopyramids shows high internal quantum efficiency, sub-ns fast recombination time (negligible built-in electric fields), and less efficiency droop even with the high In content. These results are important to realize efficient red emission based on InGaN material, providing possibilities for efficient photonic devices operating at the long wavelength visible region.