Enhancement in Output Power of Blue Nitride-Based Light-Emitting Diodes With an Electron Retarded Layer

In this study, GaN-based blue light-emitting diodes (LEDs) with an electron retarded layer (ERL) were investigated and demonstrated. The external quantum efficiency (EQE) and efficiency droop effect can be effectively improved by introducing the ERL which was attributed to the retard of the electrons rejected into the multiple quantum wells (MQWs). Therefore, the electron overflow effect can be effectively suppressed and carrier distribution can become more uniform in the MQWs. Regarding the thermal effect, the hot-cold factors of LEDs with ERL can achieve a better performance due to the carrier uniform distribution in the MQWs, which is not easily influenced by the temperature. On the other hand, the temperature dependence of the electroluminescence (EL) of LEDs with ERL also can exhibit a better property especially at lower temperature.