title: Photonic crystal light-emitting diodes fabricated by microsphere lithography.
abstract: Instead of using conventional electron lithography, a two-dimensional photonic crystal consisting of a hexagonal array of triangular air-holes was created on the surface of a GaN LED substrate using microsphere lithography. The microspheres self-assemble into a single-layered hexagonal-close-packed array acting as an etch mask. A significant enhancement in photoluminescence intensity was recorded from the PhC LED structure. A twofold increase in electroluminescence was observed from the PhC LED compared to an as-grown LED with identical geometry. Besides geometrical factors due to surface roughening, the dispersive nature of PhCs and diffractive properties of the PhC as a grating contribute to the enhancement of light extraction from the LED.
authors.affiliation: Department of Electrical and Electronic Engineering, University of Hong Kong, Pokfulam road, Hong Kong.
authors.forename: W N
authors.initials: WN
authors.lastname: Ng
authors.forename: C H
authors.initials: CH
authors.lastname: Leung
authors.forename: P T
authors.initials: PT
authors.lastname: Lai
authors.forename: H W
authors.initials: HW
authors.lastname: Choi