Realization of high efficiency AlGaN-based multiple quantum wells grown on nano-patterned sapphire substrates

Abstract

Growth of AlGaN-based multiple quantum wells (MQWs) has been attempted on nano-patterned sapphire substrates (NPSSs). By adopting a critical-temperature approach and optimizing the growth conditions including the V/III ratio and Si doping level, high-efficiency AlGaN-based MQWs with an internal quantum efficiency (IQE) greater than 80% at room temperature are realized with an emission wavelength shorter than 280 nm. Taking such high IQE MQWs as the active region, a deep-ultraviolet light-emitting-diode (DUV-LED) device is fabricated and presents single peak emission with a wavelength of 276.1 nm. The light output power (LOP) of this device reaches 17.3 mW at an injection current of 100 mA, presenting an excellent device performance.