Resonant-cavity InGaN multiple-quantum-well green light-emitting diode grown by molecular-beam epitaxy

Abstract

A resonant-cavity InGaN/GaN multiple-quantum-well (MQW) light-emitting diode, incorporating a semitransparent Bragg reflector, has been grown by molecular-beam epitaxy. A 30% reflectivity AlGaN/GaN distributed Bragg reflector and a Ni coating were used as bottom and top mirrors, for backside emission. High-resolution x-ray diffraction data reveal high-quality interfaces in both the MQW and the Bragg mirror. Room-temperature electroluminescence is centered at 507 nm, with an estimated output power of 5 μW at 20 mA. The external efficiency is increased by a factor of 12 compared to similar structures without resonant cavity.