Thermal stability of the deep ultraviolet emission from AlGaN/AlN Stranski-Krastanov quantum dots

Journal Article · Mon Dec 10 00:00:00 EST 2012 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4770075· OSTI ID:22089589

Himwas, C.; Songmuang, R.; Dang, Le Si ^[1]; Bleuse, J.; Monroy, E. ^[2]; Rapenne, L.; Sarigiannidou, E. ^[3]

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1. CEA-CNRS Group 'Nanophysique et Semiconducteurs,' Institut Neel-CNRS, 25 rue des Martyrs, 38042 Grenoble Cedex 9 (France)
2. CEA-CNRS Group 'Nanophysique et Semiconducteurs,' INAC-SP2M, CEA-Grenoble, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)
3. INP-Grenoble/Minatec, 3 parvis Louis Neel BP257, 38016 Grenoble (France)

We report on the structural and optical properties of AlGaN/AlN quantum dot (QD) superlattices synthesized by plasma-assisted molecular-beam epitaxy. Modifying the composition and geometry of the QDs, the peak emission wavelength can be shifted from 320 nm to 235 nm while keeping the internal quantum efficiency larger than 30%. The efficient carrier confinement is confirmed by the stability of the photoluminescence (PL) intensity and decay time, from low temperature up to 100 K. Above this threshold, the PL intensity decreases and the radiative lifetime increases due to carrier thermalization. We also identified the intraband electronic transition between the ground level of the conduction band and the first excited state confined along the growth axis (s-p{sub z}).

• OSTI ID: 22089589
• Journal Information: Applied Physics Letters, Vol. 101, Issue 24; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ALUMINIUM COMPOUNDS
ALUMINIUM NITRIDES
CARRIERS
EXCITED STATES
GALLIUM COMPOUNDS
GROUND LEVEL
LIFETIME
MOLECULAR BEAM EPITAXY
NITROGEN COMPOUNDS
OPTICAL PROPERTIES
PHOTOLUMINESCENCE
PLASMA
QUANTUM DOTS
QUANTUM EFFICIENCY
SEMICONDUCTOR MATERIALS
STABILITY
SUPERLATTICES
ULTRAVIOLET RADIATION
WAVELENGTHS