The spectrum-control of dual-wavelength LED with quantum dots planted in quantum wells

Abstract

A theoretical simulation of electrical and optical characteristics of GaN-based dual-wavelength light-emitting diodes (LED) with high In content in the quantum dots (QDs) which are planted in quantum wells is conducted with APSYS software. The adjustment and contrast of the structure of the devices showed that the blue and green dual-wavelength LEDs will have a broader radiation spectrum and a higher color rendering index when QDs are planted in the green quantum wells. QDs have strong blinding capacity with the carriers, and the carriers at the QDs have shorter lifetime than they are in the wetting layers, so the carrier recombination will give preference to the QDs. It is shown that the distribution of the carriers could be easily controlled by adjusting the spacing layer thickness and the spacing layer doping concentration, so as to control the radiation rate of the two active layers of the dual-wavelength LEDs. Therefore, the spectrum-control of the dual-wavelength LED with QDs planted in QWs could be realized by adjusting the concentration of quantum dots, the thickness of the spacing layer and the doping concentration in the spacing layer. This article can provide guidance for the realization of the non-phosphor white LED.