Efficiency droop alleviation in blue light emitting diodes using the InGaN/GaN triangular-shaped quantum well

The InGaN/GaN blue light emitting diode (LED) is numerically investigated using a triangular-shaped quantum well model, which involves analysis on its energy band, carrier concentration, overlap of electron and hole wave functions, radiative recombination rate, and internal quantum efficiency. The simulation results reveal that the InGaN/GaN blue light emitting diode with triangular quantum wells exhibits a higher radiative recombination rate than the conventional light emitting diode with rectangular quantum wells due to the enhanced overlap of electron and hole wave functions (above 90%) under the polarization field. Consequently, the efficiency droop is only 18% in the light emitting diode with triangular-shaped quantum wells, which is three times lower than that in a conventional LED.