LED-FDTD LED时域有限差分方法

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Efficiency enhancement of homoepitaxial

InGaN/GaN light-emitting diodes on free-standing GaN substrate with double embedded

SiO2 photonic crystals

Tongbo Wei,* Ziqiang Huo, Yonghui Zhang, Haiyang Zheng, Yu Chen, Jiankun Yang, Qiang Hu, Ruifei Duan, Junxi Wang, Yiping Zeng, and Jinmin Li Semiconductor Lighting Technology Research and Development Center, Institute of Semiconductors, Chinese

Academy of Sciences, Beijing 100083, China

*tbwei@

Abstract: Homoepitaxially grown InGaN/GaN light emitting diodes

(LEDs) with SiO2 nanodisks embedded in n-GaN and p-GaN as photonic

crystal (PhC) structures by nanospherical-lens photolithography are

presented and investigated. The introduction of SiO2 nanodisks doesn’t

produce the new dislocations and doesn’t also result in the electrical

deterioration of PhC LEDs. The light output power of homoepitaxial LEDs

with embedded PhC and double PhC at 350 mA current is increased by

29.9% and 47.2%, respectively, compared to that without PhC. The

corresponding light radiation patterns in PhC LEDs on GaN substrate show

a narrow beam shape due to strong guided light extraction, with a view

angle reduction of about 30°. The PhC LEDs are also analyzed in detail by

finite-difference time-domain simulation (FDTD) to further reveal the

emission characteristics.

OCIS codes: (230.0230) Optical devices; (230.3670) Light-emitting diodes; (160.5298)

Photonic crystals; (220.4241) Nanostructure fabrication.

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