Deep ultraviolet light-emitting diodes based on a well-ordered AlGaN nanorod array
- 16 August 2019
- journal article
- research article
- Published by Optica Publishing Group in Photonics Research
- Vol. 7 (9), B66-B72
- https://doi.org/10.1364/prj.7.000b66
Abstract
The nanorod structure is an alternative scheme to develop high-efficiency deep ultraviolet light-emitting diodes (DUV LEDs). In this paper, we first report the electrically injected 274-nm AlGaN nanorod array DUV LEDs fabricated by the nanosphere lithography and dry-etching technique. Nanorod DUV LED devices with good electrical properties are successfully realized. Compared to planar DUV LEDs, nanorod DUV LEDs present >2.5 times improvement in light output power and external quantum efficiency. The internal quantum efficiency of nanorod LEDs increases by 1.2 times due to the transformation of carriers from the exciton to the free electron hole, possibly driven by the interface state effect of the nanorod sidewall surface. In addition, the nanorod array significantly facilitates photons escaping from the interior of LEDs along the vertical direction, contributing to improved light extraction efficiency. A three-dimensional finite-different time-domain simulation is performed to analyze further in detail the TE- and TM-polarized photon extraction mechanisms of the nanostructure. Our results demonstrate the nanorod structure is a good candidate for high-efficiency DUV emitters. (C) 2019 Chinese Laser Press.Keywords
Funding Information
- National Key R&D Program of China (2016YFB0400800)
- National Natural Science Foundation of China (61875187, 61527814, 61674147, U1505253)
- Beijing Nova Program (Z181100006218007)
- Youth Innovation Promotion Association of the Chinese Academy of Sciences (2017157)
This publication has 36 references indexed in Scilit:
- Large enhancement of light extraction efficiency in AlGaN-based nanorod ultraviolet light-emitting diode structuresNanoscale Research Letters, 2014
- Enhanced optical output power of blue light-emitting diodes with quasi-aligned gold nanoparticlesNanoscale Research Letters, 2014
- Large-scale fabrication and luminescence properties of GaN nanostructures by a soft UV-curing nanoimprint lithographyNanotechnology, 2013
- Investigation of Light Extraction Efficiency in AlGaN Deep-Ultraviolet Light-Emitting DiodesApplied Physics Express, 2013
- Efficient and Directed Nano-LED Emission by a Complete Elimination of Transverse-Electric Guided ModesNano Letters, 2010
- Deep ultraviolet emission mechanisms in highly excited Al0.79Ga0.21N/AlN quantum wellsphysica status solidi (c), 2010
- Strain-modulated valence band engineering for enhancement of surface emission in polar and nonpolar plane AlN filmsApplied Physics Letters, 2009
- High-Power $\hbox{Yb}^{{\bm 3}{\bm +}}$-Doped Phosphate Fiber AmplifierIEEE Journal of Selected Topics in Quantum Electronics, 2009
- Kinetics of radiative recombination in quantum wellsPhysical Review B, 1990
- ExcitonsPhysics Education, 1970