Optimal number of quantum wells for blue InGaN/GaN light-emitting diodes

Blue InGaN/GaN light-emitting diodes with different numbers of quantum wells (QWs) are numerically investigated. With increase of QW number, the output power and forward voltage are both increased consistently. In terms of power conversion efficiency, the optimal number of QWs increases with the increase of injection currents and is twelve at experimental current of 42 A/cm². Simulation results show that the bias voltage in QW plane is reduced with increase of QW number. This effect improves the current spreading and uniformity of carrier distribution in QW plane which results in the reduction of electron leakage and enhancement of emission efficiency.