A Novel Way to Fill Green Gap of GaN-Based LEDs by Pinning Defects in Nanorod Array

Jinglin Zhan; Zhizhong Chen; Chuhan Deng; Fei Jiao; Xin Xi; Yiyong Chen; Jingxin Nie; Zuojian Pan; Haodong Zhang; Boyan Dong; Xiangning Kang; Qi Wang; Yuzhen Tong; Guoyi Zhang; Bo Shen

doi:10.3390/nano12213880

A Novel Way to Fill Green Gap of GaN-Based LEDs by Pinning Defects in Nanorod Array

Nanomaterials (Basel). 2022 Nov 3;12(21):3880. doi: 10.3390/nano12213880.

Authors

Jinglin Zhan^{1

2

3}, Zhizhong Chen^{1

4

5

6}, Chuhan Deng¹, Fei Jiao^{1

7}, Xin Xi¹, Yiyong Chen¹, Jingxin Nie¹, Zuojian Pan¹, Haodong Zhang¹, Boyan Dong¹, Xiangning Kang¹, Qi Wang⁴, Yuzhen Tong^{1

6}, Guoyi Zhang^{1

4}, Bo Shen^{1

5}

Affiliations

¹ State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China.
² Inspur (Beijing) Electronic Information Industry Co., Ltd., Beijing 100085, China.
³ State Key Laboratory of High-End Server & Storage Technology, Beijing 100085, China.
⁴ Dongguan Institute of Optoelectronics, Peking University, Dongguan 523808, China.
⁵ Yangtze Delta Institute of Optoelectronics, Peking University, Nantong 226000, China.
⁶ Research Center for Wide Bandgap Semiconductor of PKU, Gao'an 330800, China.
⁷ State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China.

Abstract

Nanorod array and planar green-emission InGaN/GaN multi-quantum well (MQW) LEDs were fabricated by lithography, nano-imprinting, and top-down etching technology. The defect-pinning effect of the nanostructure was found for the first time. The ratio of the bright regions to the global area in the panchromatic CL images of green MQW samples increased from 30% to about 90% after nano-fabrication. The overall luminous performance significantly improved. Throughout temperature-dependent photoluminescence (TDPL) and time-resolved PL (TRPL) measurements, the migration and recombination of carriers in the MQWs of green LEDs were analyzed. It was proved that nanostructures can effectively prevent carriers from being captured by surrounding nonradiative recombination centers. The overall PL integral intensity can be enhanced to above 18 times. A much lower carrier lifetime (decreasing from 91.4 to 40.2 ns) and a higher internal quantum efficiency (IQE) (increasing from 16.9% to 40.7%) were achieved. Some disputes on the defect influence were also discussed and clarified.

Keywords: GaN-based LEDs; defect-pinning effect; green gap; panchromatic and line-scanning CL.

Abstract

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