Fabrication of two-dimensional photonic crystal patterns on GaN-based light-emitting diodes using thermally curable monomer-based nanoimprint lithography

The fabrication process of photonic crystals in a p-GaN layer was established to improve the light extraction efficiency of light-emitting diodes (LEDs) by using nanoimprint lithography and inductively coupled plasma (ICP) etching process. Due to low etch selectivity of imprinted pattern, Cr mask patterns were lifted-off from the p-GaN surface and ICP etch process was followed using SiCl4-based plasma. As a result, two-dimensional pillar array patterns were uniformly fabricated on the p-GaN layer and the photoluminescence intensity of the photonic crystal patterned LED was increased by 2.6 fold compared to that of the same LED sample without photonic crystal patterns. (c) 2007 American Institute of Physics.