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arXiv · 1210.7144

Current path in light emitting diodes based on nanowire ensembles

Friederich Limbach·Christian Hauswald·Jonas Lähnemann·Martin Wölz·Oliver Brandt·Achim Trampert·Michael Hanke·Uwe Jahn·Raffaella Calarco·Lutz Geelhaar·Henning Riechert
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Abstract

Light emitting diodes (LEDs) were fabricated using ensembles of free-standing (In,Ga)N/GaN nanowires (NWs) grown on Si substrates in the self-induced growth mode by molecular beam epitaxy. Electron beam induced current analysis, cathodoluminescence as well as biased $μ$-photoluminescence spectroscopy, transmission electron microscopy, and electrical measurements indicate that the electroluminescence of such LEDs is governed by the differences in the individual current densities of the single-NW LEDs operated in parallel, i.e. by the inhomogeneity of the current path in the ensemble LED. In addition, the optoelectronic characterization leads to the conclusion that these NWs exhibit N-polarity and that the (In,Ga)N quantum well states in the NWs are subject to a non-vanishing quantum confined Stark effect.

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Friederich Limbach, Christian Hauswald, Jonas Lähnemann, Martin Wölz, Oliver Brandt, Achim Trampert, Michael Hanke, Uwe Jahn, Raffaella Calarco, Lutz Geelhaar, Henning Riechert. 2012-10-26. Current path in light emitting diodes based on nanowire ensembles. https://doi.org/10.1088/0957-4484%2F23%2F46%2F465301

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