AlGaN-based ultraviolet light-emitting diode on high-temperature annealed sputtered AlN template

Abstract We demonstrate 297.5-nm AlGaN-based ultraviolet (UV) light-emitting diodes (LEDs) grown on a high-temperature annealed (HTA) sputtered AlN template upon sapphire substrate. After HTA at 1600 °C, full width at half maximum values of (0002) and (10 1 ¯ 2) planes of the 200-nm sputtered AlN template are significantly improved from 120.7 to 2794.0 arcsec to 82.4 and 352.6 arcsec, respectively, showing comparable threading dislocation densities with the 2-μm AlN template grown by high-temperature metal organic chemical vapor deposition (MOCVD). Therefore, typical AlN template grown by MOCVD is not necessary in our study. A UV LED grown on this HTA sputtered AlN template reaches light output power of 9.83 mW at 100 mA and external quantum efficiency of 2.77% at 30 mA. Our result indicates that the HTA sputtered AlN template is able to replace the commonly used high-temperature MOCVD AlN templates and thus decrease the growth complexity and cost of AlGaN-based UV LEDs.