Disordered Antireflective Subwavelength Structures Using Ag Nanoparticles for GaN-Based Optical Device Applications

This study reports disordered antireflective subwavelength structures (SWS) on GaN and indium tin oxide (ITO) surfaces fabricated using thermally dewetted Ag nanoparticles. It is shown that the average diameter of Ag nanoparticles, which determines the optical characteristics, can be simply controlled by changing the thickness of the Ag thin film and the annealing temperature. The fabricated GaN and ITO SWS with tapered profile exhibited very low reflectance compared to that of a flat surface over a wide wavelength range.