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Ultra-violet (UV) light emitting diodes operating at 339 nm using transparent interband tunnel junctions are reported. Tunneling-based ultraviolet light emitting diodes were grown by plasma-assisted molecular beam epitaxy on 30% Al-content AlGaN layers. A low tunnel junction voltage drop is obtained through the use of compositionally graded n and p-type layers in the tunnel junction, which enhance hole density and tunneling rates. The transparent tunnel junction-based UV LED reported here show a low voltage drop of 5.55 V at 20 A/cm2 and an on-wafer external quantum efficiency of 1.02% at 80 A/cm2.
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Multi-active region AlGaN UV LEDs with transparent tunnel junctions
Abstract In this work, we demonstrate two-junction UV LEDs enabled by transparent tunnel junctions. Low voltage-drop tunnel junctions were realized in Al0.3Ga0.7N layers through a combination of high doping and compositional grading. Capacitance and current–voltage measurements confirmed the operation of two junctions in series. The voltage drop of the two-junction LED was 2.1 times that of an equivalent single-junction LED, and the two-junction LED had higher external quantum efficiency (147%) than the single junction.
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- Award ID(s):
- 2034140
- PAR ID:
- 10485266
- Publisher / Repository:
- DOI PREFIX: 10.35848
- Date Published:
- Journal Name:
- Applied Physics Express
- Volume:
- 16
- Issue:
- 8
- ISSN:
- 1882-0778
- Format(s):
- Medium: X Size: Article No. 082001
- Size(s):
- Article No. 082001
- Sponsoring Org:
- National Science Foundation
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