Improvement of light power and efficiency droop in GaN-based LEDs using graded InGaN hole reservoir layer.

InGaN-based light-emitting diodes with graded indium composition p-type InGaN hole reservoir layer (HRL) are numerically investigated using the APSYS simulation software. It is found that by gradient increasing indium composition in growth direction of the p-InGaN HRL can improve light output power, lower current leakage and efficiency droop. Based on numerical simulation and analysis, these improvements on the electrical and optical characteristics are attributed mainly to tailoring energy band in p-n junction vicinal region, and finally enhanced the hole injection efficiency and electron blocking efficiency. [ABSTRACT FROM AUTHOR]