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arXiv · 1410.3709

Understanding peculiarities in the optoelectronic characteristics of light emitting diodes based on (In,Ga)N/GaN nanowires

Mattia Musolino·Abbes Tahraoui·Friederich Limbach·Jonas Lähnemann·Uwe Jahn·Oliver Brandt·Lutz Geelhaar·Henning Riechert
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Abstract

We investigate the effect of the p-type top contact on the optoelectronic characteristics of light emitting diodes (LEDs) based on (In,Ga)N/GaN nanowire (NW) ensembles grown by molecular beam epitaxy on Si substrates. We compare devices fabricated with either Ni/Au or indium tin oxide (ITO) top contact. The NW-LEDs with ITO exhibit a number density of NWs emitting electroluminescence about ten times higher, significantly lower turn-on voltage and series resistance, and a relative external quantum efficiency more than one order of magnitude higher than the sample with Ni/Au. These results show that limitations in the performance of such devices reported so far can be overcome by improving the p-type top-contact.

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Mattia Musolino, Abbes Tahraoui, Friederich Limbach, Jonas Lähnemann, Uwe Jahn, Oliver Brandt, Lutz Geelhaar, Henning Riechert. 2014-10-14. Understanding peculiarities in the optoelectronic characteristics of light emitting diodes based on (In,Ga)N/GaN nanowires. https://doi.org/10.1063/1.4894241

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