Photonic crystal used to increase extraction efficiencyof ZnO light-emitting diodes

Piotr Kowalczewski, Włodzimierz Nakwaski, Robert P. Sarzała

Abstract


Low extraction efficiency following a low angle of total internal reflection at the output surface of simple light-emitting diodes (LEDs) considerably limits their performance and reduces their possible applications. From among various methods used to enhance extraction of radiation from LEDs manufactured from high index-of- refraction materials, an application of photonic crystals seems to be quite effective and relatively simple technologically. In the present paper, the FDTD approach is used to study the performance of a ZnO LED. As compared with a simple planar ZnO LED structure, the application of an optimized photonic crystal enables in this case an enormous increase in extraction efficiency by more than thirteen times.

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Photonics Letters of Poland - A Publication of the Photonics Society of Poland
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ISSN: 2080-2242