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DOE OSTI · 1822239

Improved forward voltage and external quantum efficiency scaling in multi-active region III-nitride LEDs

Jamal-Eddine, Zane·Gunning, Brendan P.·Armstrong, Andrew A.·Rajan, Siddharth
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Abstract

Ultra-low voltage drop tunnel junctions (TJs) were utilized to enable multi-active region blue light emitting diodes (LEDs) with up to three active regions in a single device. The multi-active region blue LEDs were grown monolithically by metal-organic chemical vapor deposition (MOCVD) without growth interruption. This is the first demonstration of a MOCVD grown triple-junction LED. Optimized TJ design enabled near-ideal voltage and EQE scaling close to the number of junctions. Furthermore, this work demonstrates that with proper TJ design, improvements in wall-plug efficiency at high output power operation are possible by cascading multiple III-nitride based LEDs.

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42 ENGINEERINGblue light emitting diodecascaded LEDgallium nitrideheterojunction tunnel junctionmulti-active region LEDoptoelectronicstunnel junction

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Jamal-Eddine, Zane, Gunning, Brendan P., Armstrong, Andrew A., Rajan, Siddharth. 2021-08-18. Improved forward voltage and external quantum efficiency scaling in multi-active region III-nitride LEDs. https://doi.org/10.35848/1882-0786%2Fac1981

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