Optimization of Doping Concentration to Obtain High Internal Quantum Efficiency and Wavelength Stability in An InGaN/GaN Blue Light-Emitting Diode

Abstract

We conduct a comprehensive study to investigate the feasibility of achieving high internal quantum efficiency (IQE) and wavelength stability in an InGaN/GaN blue light-emitting diode (LED) through numerical simulations with different doping concentrations. To ensure accurate calculations, we emulated the structure of an LED, fabricated on freestanding GaN with low defect density, abrupt interfaces, and high-performing characteristics, which resemble ideal conditions. Our objective is to determine the optimal doping concentration of the claddings using the Quantum Drift-Diffusion (QDD) model. We tested three concentrations ( C low , C middle , C h ig h ), and found that C middle produced the highest IQE of 82.5%, the most stable wavelength λ ˆ = 457.0 ± 1.2 nm in the range of (0.08–63.25) mA, an optical power of P = 14.76 mWs −1 , and a forward voltage of V middle = 3.81 V at 20 mA. We suggest that using this concentration leads to the parameters closest to those of the reference device. Simulations of InGaN/GaN blue LED using the Quantum Drift-Diffusion model current, photocurrent, cut-in voltage for an In 0.15 Ga 0.85 N/GaN LED in forward bias Spatial distribution current and recombination processes in quantum wells Photon emission spectrum and Light output power for three cladding concentrations Energy transitions for the three doping concentrations in an In 0.15 Ga 0.85 N/GaN LED