Enhanced Fabry–Perot Interferences from Nanoporous Surfaces of GaN Thin Films Patterned by Anodic Alumina Templates

The authors fabricated a nanoporous alumina template with an electrochemical anodization process and implemented this template as a mask for the nanopatterning process onto the GaN surface of an InGaN/GaN multi-quantum-well structure. The fabricated nanohole structure shows a locally ordered periodicity of a photonic crystal slab with an averaged hole distance of 105 nm and hole diameter of 60 nm. The nanohole array as a subwavelength grating shows an enhanced intensity peak at 454.8 nm with enhanced optical interference indicating the formation of subwavelength nanohole diffraction grating.