Design and demonstration of efficient transparent 30% Al-content AlGaN interband tunnel junctions

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/cm(2) and an on-wafer external quantum efficiency of 1.02% at 80 A/cm(2).

Automated summary

Ultra-violet light emitting diodes emitting at 339 nm with transparent interband tunnel junctions were achieved using plasma-assisted molecular beam epitaxy. By utilizing compositionally graded n and p-type layers, a low voltage drop at the tunnel junction was obtained, leading to enhanced hole density and tunneling rates. The transparent tunnel junction-based UV LED exhibited a voltage drop of 5.55 V at 20 A/cm(2) and an on-wafer external quantum efficiency of 1.02% at 80 A/cm(2).