title: Droop-Free, Reliable, and High-Power InGaN/GaN Nanowire Light-Emitting Diodes for Monolithic Metal-Optoelectronics.
abstract: A droop-free nitride light-emitting diode (LED) with the capacity to operate beyond the "green gap" has been a subject of intense scientific and engineering interest. While several properties of nanowires on silicon make them promising for use in LED development, the high aspect ratio of individual nanowires and their laterally discontinuous features limit phonon transport and device performance. Here, we report on the monolithic integration of metal heat-sink and droop-free InGaN/GaN quantum-disks-in-nanowire LEDs emitting at ∼710 nm. The reliable operation of our uncooled nanowire-LEDs (NW-LEDs) epitaxially grown on molybdenum was evident in the constant-current soft burn-in performed on a 380 μm × 380 μm LED. The square LED sustained 600 mA electrical stress over an 8 h period, providing stable light output at maturity without catastrophic failure. The absence of carrier and phonon transport barriers in NW-LEDs was further inferred from current-dependent Raman measurements (up to 700 mA), which revealed the low self-heating. The radiative recombination rates of NW-LEDs between room temperature and 40 °C was not limited by Shockley-Read-Hall recombination, Auger recombination, or carrier leakage mechanisms, thus realizing droop-free operation. The discovery of reliable, droop-free devices constitutes significant progress toward the development of nanowires for practical applications. Our monolithic approach realized a high-performance device that will revolutionize the way high power, low-junction-temperature LED lamps are manufactured for solid-state lighting and for applications in high-temperature harsh environment.
authors.affiliation: Photonics Laboratory, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Photonics Laboratory, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Tien Khee
authors.initials: TK
authors.lastname: Ng
authors.affiliation: Photonics Laboratory, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Rami T
authors.initials: RT
authors.lastname: ElAfandy
authors.affiliation: Photonics Laboratory, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Aditya
authors.initials: A
authors.lastname: Prabaswara
authors.affiliation: Photonics Laboratory, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Giuseppe Bernardo
authors.initials: GB
authors.lastname: Consiglio
authors.affiliation: Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Idris A
authors.initials: IA
authors.lastname: Ajia
authors.affiliation: Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Iman S
authors.initials: IS
authors.lastname: Roqan
authors.affiliation: Photonics Laboratory, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Bilal
authors.initials: B
authors.lastname: Janjua
authors.affiliation: Photonics Laboratory, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Chao
authors.initials: C
authors.lastname: Shen
authors.affiliation: Solar and Photovoltaic Engineering Research Center, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Jessica
authors.initials: J
authors.lastname: Eid
authors.affiliation: National Center for Nanotechnology, King Abdulaziz City for Science and Technology (KACST) , Riyadh 11442-6086, Saudi Arabia.
authors.forename: Ahmed Y
authors.initials: AY
authors.lastname: Alyamani
authors.affiliation: National Center for Nanotechnology, King Abdulaziz City for Science and Technology (KACST) , Riyadh 11442-6086, Saudi Arabia.
authors.forename: Munir M
authors.initials: MM
authors.lastname: El-Desouki
authors.affiliation: Photonics Laboratory, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Boon S
authors.initials: BS
authors.lastname: Ooi
keywords: Quantum-disks-in-nanowire; efficiency droop; light-emitting diode; molecular beam epitaxy