Luminescence properties of InGaN‐based dual‐wavelength light‐emitting diodes with different quantum‐well arrangements

Abstract

Optimized dual‐wavelength InGaN‐based vertical light‐emitting diode (LEDs) structures were investigated by numerical simulations. The results show that different quantum‐well arrangements in the active region play an important role in obtaining dual‐wavelength emission. It is a better way to obtain the dual‐wavelength with uniform intensity by arranging quantum wells (QW) with low indium content near the p‐side and the QW with high indium near the n‐side. This is because the QWs with lower indium near the p‐side layer have higher hole‐injection efficiency. On the other hand, arranging QW with high indium content near the p‐side leads to poor hole‐injection efficiency due to the high polarization fields. The physical and optical mechanisms of these phenomena were explained by the intensity of electrostatic fields, energy‐band diagrams, and carrier‐concentration distribution in the active region of LEDs.