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arXiv · 2001.10948

Controlling the dopant profile for SRH suppression at low current densities in $\lambda \approx$ 1330nm GaInAsP light-emitting diodes

Parthiban Santhanam·Wei Li·Bo Zhao·Chris Rogers·Dodd Joseph Gray Jr.·Phillip Jahelka·Harry A. Atwater·Shanhui Fan
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Abstract

The quantum efficiency of double hetero-junction light-emitting diodes (LEDs) can be significantly enhanced at low current density by tailoring the spatial profile of dopants to suppress Shockley-Read-Hall (SRH) recombination. To demonstrate this effect we model, design, grow, fabricate, and test a GaInAsP LED ($\lambda \approx$ 1330nm) with an unconventional dopant profile. Compared against that of our control design, which is a conventional $n^+$-$n$-$p^+$ double hetero-junction LED, the dopant profile near the $n$-$p^+$ hetero-structure of the new design displaces the built-in electric field in such a way as to suppress the J02 space charge recombination current. The design principle generalizes to other material systems and could be applicable to efforts to observe and exploit electro-luminescent refrigeration at practical power densities.

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Parthiban Santhanam, Wei Li, Bo Zhao, Chris Rogers, Dodd Joseph Gray Jr., Phillip Jahelka, Harry A. Atwater, Shanhui Fan. 2020-01-29. Controlling the dopant profile for SRH suppression at low current densities in $\lambda \approx$ 1330nm GaInAsP light-emitting diodes. https://doi.org/10.1063/5.0002058

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