Effect of Silicon Doping in the Quantum-Well Barriers on the Electrical and Optical Properties of Visible Green Light-Emitting Diodes

The effect of Si doping in the GaN quantum-well (QW) barriers of the InGaN-GaN multiple QW active region in visible green light-emitting diodes (LEDs) was studied. As the doping level of Si increases, the intensity of electroluminescence (EL) decreases, while the forward voltage of the diodes is improved. Degradation of EL is believed to be mainly due to the hole transport blocking effect caused by Si doping in the QW barriers resulting in increased potential barriers. This effect is believed to be more significant in green LEDs than in violet and blue LEDs.