Enhancing Carrier Injection Using Graded Superlattice Electron Blocking Layer for UVB Light-Emitting Diodes

Handle URI:
http://hdl.handle.net/10754/528237
Title:
Enhancing Carrier Injection Using Graded Superlattice Electron Blocking Layer for UVB Light-Emitting Diodes
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:
We have studied enhanced carrier injection by having an electron blocking layer (EBL) based on a graded superlattice (SL) design. Here, we examine, using a selfconsistent 6 × 6 k.p method, the energy band alignment diagrams under equilibrium and forward bias conditions while also considering carrier distribution and recombination rates (Shockley-Read-Hall, Auger, and radiative recombination rates). The graded SL is based on AlxGa1-xN (larger bandgap) Al0:5Ga0:5N (smaller bandgap) SL, where x is changed from 0.8 to 0.56 in steps of 0.06. Graded SL was found to be effective in reducing electron leakage and enhancing hole injection into the active region. Due to our band engineering scheme for EBL, four orders-of-magnitude enhancement were observed in the direct recombination rate, as compared with the conventional bulk EBL consisting of Al0:8Ga0:2N. An increase in the spatial overlap of carrier wavefunction was obtained due to polarization-induced band bending in the active region. An efficient single quantum-well ultraviolet-B light-emitting diode was designed, which emits at 280 nm. This is the effective wavelength for water disinfection application, among others.
KAUST Department:
Photonics Laboratory; Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division
Citation:
Enhancing Carrier Injection Using Graded Superlattice Electron Blocking Layer for UVB Light-Emitting Diodes 2014, 6 (6):1 IEEE Photonics Journal
Publisher:
Institute of Electrical and Electronics Engineers (IEEE)
Journal:
IEEE Photonics Journal
Issue Date:
Dec-2014
DOI:
10.1109/JPHOT.2014.2374596
Type:
Article
ISSN:
1943-0655
Additional Links:
http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=6967698
Appears in Collections:
Articles; Photonics Laboratory; Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division

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.accessioned2015-04-12T13:37:01Zen
dc.date.available2015-04-12T13:37:01Zen
dc.date.issued2014-12en
dc.identifier.citationEnhancing Carrier Injection Using Graded Superlattice Electron Blocking Layer for UVB Light-Emitting Diodes 2014, 6 (6):1 IEEE Photonics Journalen
dc.identifier.issn1943-0655en
dc.identifier.doi10.1109/JPHOT.2014.2374596en
dc.identifier.urihttp://hdl.handle.net/10754/528237en
dc.description.abstractWe have studied enhanced carrier injection by having an electron blocking layer (EBL) based on a graded superlattice (SL) design. Here, we examine, using a selfconsistent 6 × 6 k.p method, the energy band alignment diagrams under equilibrium and forward bias conditions while also considering carrier distribution and recombination rates (Shockley-Read-Hall, Auger, and radiative recombination rates). The graded SL is based on AlxGa1-xN (larger bandgap) Al0:5Ga0:5N (smaller bandgap) SL, where x is changed from 0.8 to 0.56 in steps of 0.06. Graded SL was found to be effective in reducing electron leakage and enhancing hole injection into the active region. Due to our band engineering scheme for EBL, four orders-of-magnitude enhancement were observed in the direct recombination rate, as compared with the conventional bulk EBL consisting of Al0:8Ga0:2N. An increase in the spatial overlap of carrier wavefunction was obtained due to polarization-induced band bending in the active region. An efficient single quantum-well ultraviolet-B light-emitting diode was designed, which emits at 280 nm. This is the effective wavelength for water disinfection application, among others.en
dc.publisherInstitute of Electrical and Electronics Engineers (IEEE)en
dc.relation.urlhttp://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=6967698en
dc.rights(c) 2014 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.en
dc.titleEnhancing Carrier Injection Using Graded Superlattice Electron Blocking Layer for UVB Light-Emitting Diodesen
dc.typeArticleen
dc.contributor.departmentPhotonics Laboratoryen
dc.contributor.departmentComputer, Electrical and Mathematical Sciences and Engineering (CEMSE) Divisionen
dc.identifier.journalIEEE Photonics Journalen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionNational Center for Nanotechnology, King Abdulaziz City for Science and Technology, Riyadh 11442-6086, Saudi Arabiaen
kaust.authorJanjua, Bilalen
kaust.authorNg, Tien Kheeen
kaust.authorOoi, Boon S.en
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