Enhanced Performance of Nitride-Based Blue LED With Step-Stage MQW Structure

A step-stage InGaN/GaN multiquantum-well (MQW) structure can enhance the efficiency of GaN-based light-emitting diodes (LEDs). Compared to dual-stage MQW LEDs, the step-stage MQW LEDs have lower forward voltage and higher light output. The measured light output power of step-stage LEDs operating at 350 mA shows an increase of approximately 23% with an external quantum efficiency (EQE) increase of 6.6%, when compared to dual-stage LEDs.