Disordered antireflective nanostructures on GaN-based light-emitting diodes using Ag nanoparticles for improved light extraction efficiency

In this study, we demonstrate GaN light-emitting diodes (LEDs) with antireflective subwavelength structures (SWS) for enhanced light extraction efficiency. To eliminate the internal Fresnel reflection, SWS were fabricated on an indium-tin-oxide (ITO) surface using an overall dry etch process of Ag nanoparticles. The average size of the Ag nanoparticles was carefully chosen by theoretical calculation of the reflective diffraction efficiency using a rigorous coupled-wave. analysis (RCWA) method. Improvement in light output power of similar to 30.2% was achieved for the fabricated ITO SWS LEDs compared to conventional LEDs, with no significant increase in the forward voltage. (C) 2010 American Institute of Physics. [doi :10.1063/1.3488001]