Abstract
Due to the intrinsic properties of larger-mismatched, stronger-polarization and non-equilibrium growth, the efficiency-droop
effect has been a critical obstacle to improve the quantum efficiency of III-nitride short-wavelength LEDs under high current
density. Quantum-Combined Stark Effect induced by built-in electric field existed within the active region of LEDs plays a key
role to reduce the quantum efficiency and causes a redshift of luminous wavelength subsequently. In this study, the light
output power, bandgap diagrams, radiative recombination efficiencies, carries concentrations, spontaneous emission
properties and electrical properties of InGaN/AlGaN violet LEDs with different polarities (c-plane, m-plane and r-plane) at
high current density of 600 A/m are investigated using APSYS software. Conclusions indicate that all the parameters of
luminescence properties and electrical properties have strong dependence on the high current density of 600 A/m, which is
contributive to eliminate the quantum-confined Stark effect and enhance the luminescence efficiency of polarity
short-wavelength LEDs. The results of this paper provide theoretical bases for further optimizing and designing the active
region and enhancing the luminous efficiency of short-wavelength LEDs.
Keywords
LED, Polarization effect, Efficiency-droop effect, Non-polarity.
Citation
WANG DANGHUI, HAN YE, XU TIANHAN, ZHANG YANG, Numerical investigation on quantum-confined stark effect and polarization effect of short-wavelength LEDs, Optoelectronics and Advanced Materials - Rapid Communications, 17, 1-2, January-February 2023, pp.21-27 (2023).
Submitted at: March 21, 2022
Accepted at: Feb. 6, 2023