標題: Alternative Strategy to Reduce Surface Recombination for InGaN/GaN Micro-light-Emitting Diodes-Thinning the Quantum Barriers to Manage the Current Spreading
作者: Chang, Le
Yeh, Yen-Wei
Hang, Sheng
Tian, Kangkai
Kou, Jianquan
Bi, Wengang
Zhang, Yonghui
Zhang, Zi-Hui
Liu, Zhaojun
Kuo, Hao-Chung
光電工程學系
光電工程研究所
Department of Photonics
Institute of EO Enginerring
關鍵字: Micro-LED;Sidewall defects;Nonradiative recombination;Current spreading;Hole injection;IQE
公開日期: 6-Aug-2020
摘要: Owing to high surface-to-volume ratio, InGaN-based micro-light-emitting diodes (mu LEDs) strongly suffer from surface recombination that is induced by sidewall defects. Moreover, as the chip size decreases, the current spreading will be correspondingly enhanced, which therefore further limits the carrier injection and the external quantum efficiency (EQE). In this work, we suggest reducing the nonradiative recombination rate at sidewall defects by managing the current spreading effect. For that purpose, we properly reduce the vertical resistivity by decreasing the quantum barrier thickness so that the current is less horizontally spreaded to sidewall defects. As a result, much fewer carriers are consumed in the way of surface nonradiative recombination. Our calculated results demonstrate that the suppressed surface nonradiative recombination can better favor the hole injection efficiency. We also fabricate the mu LEDs that are grown on Si substrates, and the measured results are consistent with the numerical calculations, such that the EQE for the proposed mu LEDs with properly thin quantum barriers can be enhanced, thanks to the less current spreading effect and the decreased surface nonradiative recombination.
URI: http://dx.doi.org/10.1186/s11671-020-03372-3
http://hdl.handle.net/11536/155414
ISSN: 1931-7573
DOI: 10.1186/s11671-020-03372-3
期刊: NANOSCALE RESEARCH LETTERS
Volume: 15
Issue: 1
起始頁: 0
結束頁: 0
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