Demonstration of AlGaN-Based Deep-Ultraviolet Light-Emitting Diodes on High-Quality AlN Templates

The authors demonstrate AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) on high-quality AlN/sapphire template (AlN template) by evaluating its characteristics. LED structures can be grown directly on 2-in.-diameter AlN template by metal–organic chemical vapor deposition. AlGaN epilayers are confirmed to have high crystal quality on AlN template through X-ray diffraction (XRD) and cross-sectional transmission electron microscopy (TEM). The fabricated LEDs exhibit a sharp single peak emission at DUV region around 260–270 nm from electroluminescence spectra measured at room temperature. The light intensity and current–voltage characteristics are improved by using higher quality AlN template as underlying substrate. This could facilitate the production of high-performance DUV-LEDs.