Extraction efficiency enhancement of LEDs using 2-D photonic crystal  

作　　者：李志全 王亚男 李文超 曹平 张景茹 

机构地区：[1]Institute of Electric and Engineering,Yanshan University,Qinhuangdao 066004,China [2]Department of Automation,Northeastern University at Qinhuangdao,Qinhuangdao 066004,China

出　　处：《Optoelectronics Letters》2012年第3期186-189,共4页光电子快报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.60877047);the Natural Science Foundation of Hebei Province (No.2010002002)

摘　　要：Using photonic crystals (PCs), the extraction efficiency of the light-emitting diodes (LEDs) can be greatly enhanced by the effects of photonic band gap (PBG) and grating diffraction. The two theoretical methods are also discussed. Meanwhile, we demonstrate that LEDs can achieve high extraction efficiency by employing photonic crystal as diffraction grating. PCs with square lattice of cylindrical unit cells are fabricated in GaN layer of GaN-based blue LED. We present a theoretical discussion on the extraction efficiency of PC-LED, which relies on the effective medium theory and transmission matrix method to investigate the effect of lattice constant. The results show that the extraction efficiency of the high performance LEDs can achieve 61.8% when the lattice constant is 270 nm.

关 键 词：DIFFRACTION Diffraction gratings EFFICIENCY EXTRACTION Gallium nitride Lattice constants Microcomputers Photonic band gap 

分 类 号：TN312.8[电子电信—物理电子学]