High-Temperature Electroluminescence of InGaN/GaN Light-Emitting Devices with Multiple Quantum Barriers

We investigate the high-temperature characteristics of InGaN/GaN multiple quantum well light-emitting devices with and without multiple quantum barriers (MQBs) in depth. The electroluminescence measurements were carried out over a temperature range from 200 to 380 K and an injection current level from 1 to 100 mA. Enhanced carrier confinement and stronger carrier localization in the active layer are achieved for the sample with MQBs. Furthermore, it is found that the external quantum efficiency of the sample possessing MQBs is higher than that of the sample with GaN barriers. The MQB structure improves the high-temperature operation of light-emitting devices.