Quaternary AlInGaN/AlInGaN Polarization-Engineered Green Lights-Emitting Diodes by Using Inverted Trapezoidal Quantum Barriers

Abstract

In this paper, a structure design using grading quaternary AlInGaN as inverted trapezoidal multiple quantum barriers is shown. This paper proposes an inverted trapezoidal structure in quantum barriers to decelerate the transmission of the electron which will enhance efficient carrier injection into the quantum wells and get a more uniform distribution of carriers. The polarization-matched AlInGaN/AlInGaN structures have less polarization and increase the overlap of electron and hole wave function, effectively improving the internal quantum efficiency and wall-plug efficiency, and making the In composition adjustable. The results show that the Inverted trapezoidal polarization-matched AlInGaN structure significantly improves the phenomenon of “green gap” and “green droop.” As a result, the new structure mitigates the droop ratio from 25.5% to 7%, and the LED power is increased from 59.95 mW to 109.68 mW at 200 mA. Finally, the device exhibits a uniform current distribution and greater radiative recombination while reducing resistance.