Quantum Efficiency Improvement of InGaN Near Ultraviolet LED Design by Genetic Algorithm


ALP I. O., Oner B., YÜKSEL A. E., Çiftci Y.

Sakarya Üniversitesi Fen Bilimleri Enstitüsü Dergisi, vol.27, no.1, pp.94-112, 2023 (TRDizin) identifier

Abstract

A near-ultraviolet (367-nm) InGaN light-emitting diode (LED) with 5.75 nm quantum well depth was designed and both internal/external quantum efficiency (IQE/EQE) values were optimized considering the effects of non-radiative recombination rates and possible fabrica-tion errors. Firstly, the IQE of the design was enhanced by a genetic algorithm code which was developed particularly for this study. Distributed Bragg Reflectors and optional ultra-thin 1nm AlN interlayer were also used to increase overall light extraction efficiency. Then, alloy and doping concentration effects on wavelength-dependent optical and structural parameters were analyzed via the CASTEP software package based on density functional theory to pre-sent a more detailed and realistic optimization. The relatively great values of 42.6% IQE and 90.2% LEE were achieved. The final structure with 1.00 mm × 1.00 mm surface area requires only 200 mW input power to operate at 3.75 V.