SiO2Nanopillars on Microscale Roughened Surface of GaN-Based Light-Emitting Diodes by SILAR-Based Method
We reported the SiO2nanopillars on microscale roughened surface on GaN-based LED to enhance light-extraction efficiency. ZnO nanoparticles were deposited on SiO2as an etching mask before ICP etching SiO2by successive ionic layer adsorption and reaction method (SILAR), and the different heights of SiO2nanopillars on microroughened ITO/GaN were obtained after etching. Compared to a regular (flat surface) GaN-based LED, the light output power for a LED with microroughening was increased by 33%. Furthermore, the proposed LEDs with SiO2nanopillars on microroughened surface show the enhancement in light output power by 42.7%–49.1% at 20 mA. The increase in light output power is mostly attributed to reduction in Fresnel reflection by rough surface. The height of SiO2nanopillars was increasing cause resulting in more rough on the microscale surface of GaN-based LEDs.