InGaN quantum well with gradually varying indium content for high-efficiency GaN-based green light-emitting diodes.

High-efficiency GaN-based green LEDs are of paramount importance to the development of the monolithic integration of multicolor emitters and full-color high-resolution displays. Here, the InGaN quantum well with gradually varying indium (In) content was proposed for improving the performance of GaN-based green LEDs. The InGaN quantum well with gradually varying In content not only alleviates the quantum-confined Stark effect (QCSE), but also yields a low Auger recombination rate. Consequently, the gradual In content green LEDs exhibited increased light output power (LOP) and reduced efficiency droop as compared to constant In content green LEDs. At 60 A/cm, the LOPs of the constant In content green LEDs and the gradual In content green LEDs were 33.9 mW and 55.2 mW, respectively. At 150 A/cm, the efficiency droops for the constant In content green LEDs and the gradual In content green LEDs were 61% and 37.6%, respectively. This work demonstrates the potential for the gradual In content InGaN to replace constant In content InGaN as quantum wells in LED devices in a technologically and commercially effective manner.