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arXiv · 2001.03510

Limitation of simple np-n tunnel junction based LEDs grown by MOVPE

Yoann Robin·Quentin Bournet·Geoffrey Avit·Markus Pristovsek·Yamina André·Agnès Trassoudaine·Hiroshi Amano
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Abstract

We show evidence that tunnel junctions (TJs) in GaN grown by metal-organic vapor phase epitaxy are dominated by trap-assisted (Poole-Frenkel) tunneling. This stems from observations of the careful optimized doping for the TJs. Especially the p$^{++}$ and the n$^{++}$ layers are far from ideal. The n$^{++}$ layer induces 3D growth, which can be seen by a rising oxygen signal in Secondary Ions Mass Spectroscopy (SIMS). Furthermore, Mg segregation observed by SIMS indicates a depletion region of more than 10 nm. Still, we could realize TJ based LEDs with a low penalty voltage of 1.1 V and a specific differential resistance of about 10$^{-2}$ $\Omega$.cm$^2$ at 20 mA without using an InGaN interlayer.

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Yoann Robin, Quentin Bournet, Geoffrey Avit, Markus Pristovsek, Yamina André, Agnès Trassoudaine, Hiroshi Amano. 2020-01-10. Limitation of simple np-n tunnel junction based LEDs grown by MOVPE. https://doi.org/10.1088/1361-6641/abad73

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