Improved carrier injection of AlGaN-based deep ultraviolet light emitting diodes with graded superlattice electron blocking layers.

A DUV-LED with a graded superlattice electron blocking layer (GSL-EBL) is demonstrated to show improved carrier injection into the multi-quantum well region. The structures of modified EBLs are designed simulation. The simulation results show the carrier behavior mechanism of DUV-LEDs with a single EBL (S-EBL), graded EBL (G-EBL), and GSL-EBL.

Deep-Ultraviolet AlGaN/AlN Core-Shell Multiple Quantum Wells on AlN Nanorods via Lithography-Free Method.

We report deep ultraviolet (UVC) emitting core-shell-type AlGaN/AlN multiple quantum wells (MQWs) on the AlN nanorods which are prepared by catalyst/lithography free process. The MQWs are grown on AlN nanorods on a sapphire substrate by polarity-selective epitaxy and etching (PSEE) using high-temperature metal organic chemical vapor deposition. The AlN nanorods prepared through PSEE have a low dislocation density because edge dislocations are bent toward neighboring N-polar AlN domains.