Title :
On the Efficiency Decrease of the GaN Light-Emitting Nanorod Arrays
Author :
Liang-Yi Chen ; Chi-kang Li ; Jin-Yi Tan ; Li-Chuan Huang ; Yuh-Renn Wu ; Jian Jang Huang
Author_Institution :
Grad. Inst. of Photonics & Optoelectron., Nat. Taiwan Univ., Taipei, Taiwan
Abstract :
Nanostructure light emitting arrays, with the mitigated quantum confined stark effect, provide a different angle to investigate the efficiency decrease in the GaN based LEDs. In this paper, the external quantum efficiency and the electroluminescent spectra of GaN based nanorod LEDs are characterized through experiments and simulations. The strains in the InGaN/GaNnanorods are varied with the choice of nanorod sidewall passivation materials. Our results indicate that Auger recombination dominates at low-level currents. However, even though the effect of Auger accounts fora higher percentage weighting, the increase number of leakage carriers out of quantum wells is responsible for the efficiency drop at high current levels.
Keywords :
Auger effect; III-V semiconductors; Stark effect; electroluminescence; electron-hole recombination; gallium compounds; indium compounds; light emitting diodes; nanorods; wide band gap semiconductors; Auger recombination; InGaN-GaN; electroluminescent spectra; external quantum efficiency; leakage carriers; light-emitting nanorod arrays; low-level currents; mitigated quantum confined stark effect; nanorod LED; nanorod sidewall passivation materials; nanostructure light emitting arrays; quantum wells; Current measurement; Gallium nitride; Light emitting diodes; Passivation; Quantum well devices; Radiative recombination; Strain; Light-emitting diodes; nanofabrication and quantum wells; nanostructures;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2013.2237885