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Publication Citation: Towards Discrete Axial p-n Junction Nanowire LEDs Grown by Plasma-Assisted MBE

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Author(s): Matthew D. Brubaker;
Title: Towards Discrete Axial p-n Junction Nanowire LEDs Grown by Plasma-Assisted MBE
Published: March 06, 2013
Abstract: In this paper we investigate axial p-n junction GaN nanowires grown by plasma-assisted MBE, with particular attention to the effect of Mg doping on the device characteristics of individual nanowire LEDs. We observe that single-nanowire LEDs produce measureable band-gap electroluminescence for a significant fraction of devices only when a thin AlGaN electron blocking layer is incorporated into the device structure near the junction. This observation and the low external quantum efficiency of the devices indicate that the primary non-radiative loss mechanism is the overflow of electrons from the n-type region through the p-type region and directly into the p-side contact. This effect is exacerbated by low p-type doping activity and Schottky-like contacts, which were confirmed by I-V measurements of the p-regions in junction nanowires as well as nanowires doped with Mg only. Our observations also show that diode-like I-V characteristics are observed even when an ideal p-n junction is absent.
Citation: Journal of Electronic Materials
Volume: 42
Pages: pp. 868 - 874
Keywords: Gallium Nitride;Nanowires;Molecular Beam Epitaxy;LEDs
Research Areas: Nanowires, Optoelectronics, Semiconductor Materials
DOI: http://dx.doi.org/10.1007/s11664-013-2498-y   (Note: May link to a non-U.S. Government webpage)