Presentation
19 April 2017 Long wavelength emission on relaxed InGaN substrates (Conference Presentation)
Armelle Even, Gautier Laval, Olivier Ledoux, Pierre Ferret, David Sotta, Eric Guiot, Francois Levy, Ivan-Christophe Robin, Amélie Dussaigne
Author Affiliations +
Abstract
InGaN based LEDs are known to be very efficient in the blue range. However, although InGaN can theoretically cover all visible range, quantum efficiency drops when emission wavelength emission is increased due to quantum confined Stark effect. Furthermore, indium incorporation is hindered by compressive strain induced by lattice mismatch between InGaN and GaN. To tackle the lattice mismatch problem, a full InGaN structure on a relaxed InGaN substrate is proposed. The structure consisting of five InxGa1-xN / InyGa1-yN multi quantum wells on top of an InyGa1-yN buffer layer is grown by MOVPE on an InGaNOs substrate from Soitec company. Three InGaNOs substrates of lattice parameters of 3.190, 3.200 and 3.205 Ångströms were co-loaded in order to compare their ability to incorporate indium for the same growth conditions. For reference, a sample grown on GaN template will allow us to compare the wavelength red-shift resulting of the use of InGaNOs template. The samples were characterized by photoluminescence at room temperature using 375 nm and 405 nm laser diodes. It is shown that long wavelengths can be reached thanks to the use of InGaNOs substrates. For same active region growth conditions as reference sample, a red-shift up to 65 nm (from 445 to 510 nm) is observed, demonstrating InGaNOs potential for easier In incorporation. Using different growth conditions, wavelengths up to 600 nm have been reached. First internal quantum efficiency measurements demonstrate a good quality material. InGaNOs seems promising for emission in the “green gap”and beyond.
Conference Presentation
© (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Armelle Even, Gautier Laval, Olivier Ledoux, Pierre Ferret, David Sotta, Eric Guiot, Francois Levy, Ivan-Christophe Robin, and Amélie Dussaigne "Long wavelength emission on relaxed InGaN substrates (Conference Presentation)", Proc. SPIE 10104, Gallium Nitride Materials and Devices XII, 101040G (19 April 2017); https://doi.org/10.1117/12.2252290
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KEYWORDS
Indium gallium nitride

Gallium nitride

Indium

Quantum efficiency

Internal quantum efficiency

Light emitting diodes

Luminescence

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