Enhancing carrier injection in the active region of a 280nm emission wavelength LED using graded hole and electron blocking layers

Handle URI:
http://hdl.handle.net/10754/555668
Title:
Enhancing carrier injection in the active region of a 280nm emission wavelength LED using graded hole and electron blocking layers
Authors:
Janjua, Bilal ( 0000-0001-9974-9879 ) ; Ng, Tien Khee ( 0000-0002-1480-6975 ) ; Alyamani, Ahmed Y.; El-Desouki, Munir M.; Ooi, Boon S. ( 0000-0001-9606-5578 )
Abstract:
A theoretical investigation of AlGaN UV-LED with band engineering of hole and electron blocking layers (HBL and EBL, respectively) was conducted with an aim to improve injection efficiency and reduce efficiency droop in the UV LEDs. The analysis is based on energy band diagrams, carrier distribution and recombination rates (Shockley-Reed-Hall, Auger, and radiative recombination rates) in the quantum well, under equilibrium and forward bias conditions. Electron blocking layer is based on AlaGa1-aN / Al b → cGa1-b → 1-cN / AldGa 1-dN, where a < d < b < c. A graded layer sandwiched between large bandgap AlGaN materials was found to be effective in simultaneously blocking electrons and providing polarization field enhanced carrier injection. The graded interlayer reduces polarization induced band bending and mitigates the related drawback of impediment of holes injection. Similarly on the n-side, the Alx → yGa1-x → 1-yN / AlzGa 1-zN (x < z < y) barrier acts as a hole blocking layer. The reduced carrier leakage and enhanced carrier density in the active region results in significant improvement in radiative recombination rate compared to a structure with the conventional rectangular EBL layers. The improvement in device performance comes from meticulously designing the hole and electron blocking layers to increase carrier injection efficiency. The quantum well based UV-LED was designed to emit at 280nm, which is an effective wavelength for water disinfection application.
KAUST Department:
Photonics Laboratory
Citation:
Janjua, Bilal, Tien K. Ng, Ahmed Y. Alyamani, Munir M. El-Desouki, and Boon S. Ooi. "Enhancing carrier injection in the active region of a 280nm emission wavelength LED using graded hole and electron blocking layers." In SPIE OPTO, pp. 90030S-90030S. International Society for Optics and Photonics, 2014
Publisher:
SPIE-Intl Soc Optical Eng
Journal:
Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XVIII
Conference/Event name:
Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XVIII
Issue Date:
27-Feb-2014
DOI:
10.1117/12.2039347
Type:
Conference Paper
Additional Links:
http://proceedings.spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.2039347
Appears in Collections:
Conference Papers; Photonics Laboratory; Photonics Laboratory

Full metadata record

DC FieldValue Language
dc.contributor.authorJanjua, Bilalen
dc.contributor.authorNg, Tien Kheeen
dc.contributor.authorAlyamani, Ahmed Y.en
dc.contributor.authorEl-Desouki, Munir M.en
dc.contributor.authorOoi, Boon S.en
dc.date.accessioned2015-05-25T08:31:35Zen
dc.date.available2015-05-25T08:31:35Zen
dc.date.issued2014-02-27en
dc.identifier.citationJanjua, Bilal, Tien K. Ng, Ahmed Y. Alyamani, Munir M. El-Desouki, and Boon S. Ooi. "Enhancing carrier injection in the active region of a 280nm emission wavelength LED using graded hole and electron blocking layers." In SPIE OPTO, pp. 90030S-90030S. International Society for Optics and Photonics, 2014en
dc.identifier.doi10.1117/12.2039347en
dc.identifier.urihttp://hdl.handle.net/10754/555668en
dc.description.abstractA theoretical investigation of AlGaN UV-LED with band engineering of hole and electron blocking layers (HBL and EBL, respectively) was conducted with an aim to improve injection efficiency and reduce efficiency droop in the UV LEDs. The analysis is based on energy band diagrams, carrier distribution and recombination rates (Shockley-Reed-Hall, Auger, and radiative recombination rates) in the quantum well, under equilibrium and forward bias conditions. Electron blocking layer is based on AlaGa1-aN / Al b → cGa1-b → 1-cN / AldGa 1-dN, where a < d < b < c. A graded layer sandwiched between large bandgap AlGaN materials was found to be effective in simultaneously blocking electrons and providing polarization field enhanced carrier injection. The graded interlayer reduces polarization induced band bending and mitigates the related drawback of impediment of holes injection. Similarly on the n-side, the Alx → yGa1-x → 1-yN / AlzGa 1-zN (x < z < y) barrier acts as a hole blocking layer. The reduced carrier leakage and enhanced carrier density in the active region results in significant improvement in radiative recombination rate compared to a structure with the conventional rectangular EBL layers. The improvement in device performance comes from meticulously designing the hole and electron blocking layers to increase carrier injection efficiency. The quantum well based UV-LED was designed to emit at 280nm, which is an effective wavelength for water disinfection application.en
dc.publisherSPIE-Intl Soc Optical Engen
dc.relation.urlhttp://proceedings.spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.2039347en
dc.rightsArchived with thanks to Proceedings of SPIEen
dc.titleEnhancing carrier injection in the active region of a 280nm emission wavelength LED using graded hole and electron blocking layersen
dc.typeConference Paperen
dc.contributor.departmentPhotonics Laboratoryen
dc.identifier.journalLight-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XVIIIen
dc.conference.date2014-02-04 to 2014-02-06en
dc.conference.nameLight-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XVIIIen
dc.conference.locationSan Francisco, CA, USAen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionKing Abdulaziz City for Science and Technology (KACST), Riyadh, 11442-6086, Kingdom of Saudi Arabia (KSA)en
kaust.authorNg, Tien Kheeen
kaust.authorOoi, Boon S.en
kaust.authorJanjua, Bilalen
All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.