Reflective Metal/Semiconductor Tunnel Junctions for Hole Injection in AlGaN UV LEDs
arXiv:1705.08414 · doi:10.1063/1.4997328
Abstract
In this work, we investigate the use of nanoscale polarization engineering to achieve efficient hole injection from metals to ultra-wide band gap AlGaN, and we show that UV-reflective aluminum (Al) layers can be used for hole injection into p-AlGaN. The dependence of tunneling on the work function of the metal was investigated, and it was found that highly reflective Al metal layers can enable efficient hole injection into p-AlGaN, despite the relatively low work function of Al. Efficient tunneling hole injection was confirmed by light emission at 326 nm with on-wafer peak external quantum efficiency and wall-plug efficiency of 2.65% and 1.55%, respectively. A high power density of 83.7 W/cm2 was measured at 1200 kA/cm2. The metal/semiconductor tunnel junction structure demonstrated here could provide significant advantages for efficient and manufacturable device topologies for high power UV emitters.
References in corpus (4)
- MBE-grown 232-270 nm Deep-UV LEDs using Monolayer thin Binary GaN/AlN quantum heterostructures
- Interband Tunneling for Hole Injection in III-Nitride Ultra-violet Emitters
- Design and Demonstration of Ultra Wide Bandgap AlGaN Tunnel Junctions
- Design of P-Type Cladding Layers for Tunnel-Injected UVA Light Emitting Diodes