Investigation of blue InGaN light-emitting diodes with step-like quantum well

The concept of a step-like quantum well is proposed with the purpose to reduce the influence of electrostatic field resulting from the piezoelectric effect on the optical performance of blue InGaN light-emitting diodes. Particularly, the optical properties of the LED structures with the In0.23Ga0.77N single quantum well, In0.20Ga0.80N/In0.26Ga0.74N step-like quantum well, and In0.26Ga0.74N/In0.20Ga0.80N step-like quantum well are numerically investigated in detail. Simulation results show that the In0.20Ga0.80N/In0.26Ga0.74N step-like-quantum-well LED structure has the best optical performance in virtue of the improvement in spatial overlap of electrons and holes in the quantum well.