Translator Disclaimer
23 February 2018 Demonstration of AlGaN-delta-GaN QW by plasma-assisted molecular beam epitaxy for 260-nm ultraviolet light emitting diodes
Author Affiliations +
III-nitride ultraviolet (UV) light emitting diodes (LEDs) with emission wavelengths in the range of 250-280 nm have attracted considerable interest for applications such as germicidal disinfection and biological detection. However, the widely-used AlGaN quantum well (QW)-based LEDs at such wavelengths suffer from low quantum efficiencies. One main factor that limits the AlGaN QW LED efficiency at ~250-280 nm is the suffering of the severe band mixing effect caused by the valence subbands crossover, as well as the Quantum Confined Stark Effect (QCSE). Therefore, the novel AlGaN-delta-GaN QW design was proposed to address these issues in order to realize high-efficiency deep-UV LEDs.

Here, we proposed a novel Al0.9Ga0.1N-delta-GaN QW by inserting an ultra-thin delta-GaN layer into a conventional Al0.9Ga0.1N QW active region. The physics from such QW design was investigated by 6-band k·p model and the structure was experimentally demonstrated by Plasma-assisted Molecular Beam Epitaxy (PAMBE). The calculated results show that the insertion of delta-GaN layer could successfully address the band mixing issue and QCSE, leading to a significant improvement in spontaneous emission rate as compared to that of Al0.55Ga0.45N QW at 260 nm. The 5-period Al0.9Ga0.1N-delta-GaN QW with 3-nm AlN barrier was grown on AlN/sapphire substrate by MBE with ~2-monolayer delta-GaN layer, which was evidenced by the cross-sectional transmission electron microscope. The two-photon photoluminescence spectrum presented a single peak emission centered at 260 nm from the grown Al0.9Ga0.1N-deltaGaN QW with a full width at half maximum of 12 nm, which shows that the demonstrated QW would be promising for high-efficiency UV LEDs.
Conference Presentation
© (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Cheng Liu, Kevin Lee, S. M. Islam, Huili Xing, Debdeep Jena, and Jing Zhang "Demonstration of AlGaN-delta-GaN QW by plasma-assisted molecular beam epitaxy for 260-nm ultraviolet light emitting diodes", Proc. SPIE 10532, Gallium Nitride Materials and Devices XIII, 105320W (23 February 2018);


Deep-ultraviolet LEDs fabricated in AlInGaN using MEMOCVD
Proceedings of SPIE (October 20 2004)
MOVPE growth for UV-LEDs
Proceedings of SPIE (February 03 2009)
Simulation of deep ultraviolet light-emitting diodes
Proceedings of SPIE (September 14 2007)
AlGaN layers grown on AlGaN buffer layer and GaN buffer...
Proceedings of SPIE (January 04 2008)
III N multiple quantum wells based 285 to 340...
Proceedings of SPIE (July 03 2003)

Back to Top