The effect of high temperature on the optical properties of InGaN/GaN blue light-emitting diodes with multiquantum barriers

摘要

The effect of the temperature on the characteristics of InGaN/GaN multiple quantum well (MQW) light-emitting diodes (LEDs) with multiquantum barriers (MQBs) has been investigated in-depth over a broad range of temperatures from 200 to 370 K. It was found that if the device had an MQB structure it exhibited stronger blue emission as well as had a larger capture cross-section fraction than did the conventional MQW LEDs. This was due to the MQB configuration, which offered a large contribution to the exciton recombination; the adoption of an appropriate heterobarrier allows the achievement of improved LED performance. However, the unavoidable disordering formed in the In-rich MQB heterostructures caused not only EL intensity deterioration, but also rapid quenching rate at temperatures above 300 K.