Light extraction in individual GaN nanowires on Si for LEDs
Name
Gradecak_Light extraction.pdf
Size
552.24 KB
Format
Adobe PDF
Checksum (MD5)
1c7ca64167e31e72c02837d9bb5b8951
Author(s)
Zhou, Xiang
Chesin, Jordan Paul
Gradecak, Silvija
Date Issued
October 2012
Journal
Proceedings of SPIE--the International Society for Optical Engineering; v.8467
Publisher
SPIE
Citation
Chesin, Jordan, Xiang Zhou, and Silvija Gradečak. “Light extraction in individual GaN nanowires on Si for LEDs.” In Nanoepitaxy: Materials and Devices IV, edited by Nobuhiko P. Kobayashi, A. Alec Talin, and M. Saif Islam, 846703-846703-10. SPIE - International Society for Optical Engineering, 2012. © (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE)
Version
Final published version
Abstract
GaN-based nanowires hold great promise for solid state lighting applications because of their waveguiding properties and the ability to grow nonpolar GaN nanowire-based heterostructures, which could lead to increased light extraction and improved internal quantum efficiency, respectively. In addition, GaN nanowires can be grown directly on Si substrates, providing an inexpensive and scalable platform for device fabrication. We use finite difference time domain photonic simulations to explore light extraction efficiency enhancement in GaN nanowire-based light-emitting diodes (LEDs) on Si. Emission polarization and the placement of the emission source along the length of the nanowire were taken into consideration. We find that the optimal placement of the emission source is determined by the light reflection at the nanowire-air and nanowire-substrate interfaces and the coupling of emitted radiation into the waveguided modes, resulting in extraction efficiencies of up to 50%. Our approach to optimizing light extraction via simulation techniques can be applied to more realistic large-scale devices to guide experimental work towards nanowire-based LEDs with potentially greater efficiencies than their thin-film counterparts.
MIT Department
Massachusetts Institute of Technology. Department of Materials Science and Engineering
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1117/12.970456
