Measurement of radiative and nonradiative recombination rate in InGaAsP-InP LED's

1992 ◽  
Vol 28 (8) ◽  
pp. 1746-1750 ◽  
Author(s):  
M. Kot ◽  
K. Zdansky
Keyword(s):  
Recombination Rate ◽  
Nonradiative Recombination ◽  
Nonradiative Recombination Rate

Preparation condition and recombination rates at radiative defects in a-Si:H

2014 ◽  
Vol 92 (7/8) ◽  
pp. 561-564
Author(s):  
Chisato Ogihara ◽  
Yuta Shintoku ◽  
Kei Yamaguchi ◽  
Kazuo Morigaki
Keyword(s):  
Recombination Rate ◽  
Radiative Recombination ◽  
Preparation Condition ◽  
Thermal Excitation ◽  
Nonradiative Recombination ◽  
Radiative Recombination Rate ◽  
Recombination Rates ◽  
Strong Electron ◽  
Temperature Variations ◽  
Preparation Conditions

Recombination rates at radiative defects in the hydrogenated amorphous silicon films prepared at various preparation conditions, estimated from intensities and characteristic lifetimes of defect photoluminescence, have been investigated. The temperature variations of the radiative recombination rate are discussed in terms of a model in which the increase of the radiative recombination rate is attributed to the thermal excitation of the holes from deep and strongly localised tail states to shallow and more extended tail states. The temperature variations of nonradiative recombination rate are discussed in terms of a theory for the case of strong electron–phonon coupling.

scholarly journals Reducing the impact of Auger recombination in quasi-2D perovskite light-emitting diodes

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yuanzhi Jiang ◽  
Minghuan Cui ◽  
Saisai Li ◽  
Changjiu Sun ◽  
Yanmin Huang ◽  
...  
Keyword(s):  
Recombination Rate ◽  
Auger Recombination ◽  
Light Emitting Diodes ◽  
Quantum Yields ◽  
Excitation Density ◽  
Nonradiative Recombination ◽  
Light Emitting ◽  
Order Of Magnitude ◽  
The Impact ◽  
Auger Recombination Rate

AbstractRapid Auger recombination represents an important challenge faced by quasi-2D perovskites, which induces resulting perovskite light-emitting diodes’ (PeLEDs) efficiency roll-off. In principle, Auger recombination rate is proportional to materials’ exciton binding energy (Eb). Thus, Auger recombination can be suppressed by reducing the corresponding materials’ Eb. Here, a polar molecule, p-fluorophenethylammonium, is employed to generate quasi-2D perovskites with reduced Eb. Recombination kinetics reveal the Auger recombination rate does decrease to one-order-of magnitude lower compared to its PEA+ analogues. After effective passivation, nonradiative recombination is greatly suppressed, which enables resulting films to exhibit outstanding photoluminescence quantum yields in a broad range of excitation density. We herein demonstrate the very efficient PeLEDs with a peak external quantum efficiency of 20.36%. More importantly, devices exhibit a record luminance of 82,480 cd m−2 due to the suppressed efficiency roll-off, which represent one of the brightest visible PeLEDs yet.

Influence of MBE Growth Conditions on Dislocation Densities of GaAs/Ge Epilayers Grown on Silicon Substrates

1985 ◽  
Vol 43 ◽  
pp. 364-365
Author(s):  
K.M. Hones ◽  
P. Sheldon ◽  
B.G. Yacobi ◽  
A. Mason
Keyword(s):  
High Efficiency ◽  
Lattice Mismatch ◽  
Low Cost ◽  
Growth Conditions ◽  
Nonradiative Recombination ◽  
Device Structure ◽  
Si Substrates ◽  
Transmission Electron ◽  
Dislocation Densities ◽  
Dislocation Type

There is increasing interest in growing epitaxial GaAs on Si substrates. Such a device structure would allow low-cost substrates to be used for high-efficiency cascade- junction solar cells. However, high-defect densities may result from the large lattice mismatch (∼4%) between the GaAs epilayer and the silicon substrate. These defects can act as nonradiative recombination centers that can degrade the optical and electrical properties of the epitaxially grown GaAs. For this reason, it is important to optimize epilayer growth conditions in order to minimize resulting dislocation densities. The purpose of this paper is to provide an indication of the quality of the epitaxially grown GaAs layers by using transmission electron microscopy (TEM) to examine dislocation type and density as a function of various growth conditions. In this study an intermediate Ge layer was used to avoid nucleation difficulties observed for GaAs growth directly on Si substrates. GaAs/Ge epilayers were grown by molecular beam epitaxy (MBE) on Si substrates in a manner similar to that described previously.

Low-Temperature Operation of Green, Blue and UV InGaN/GaN Multiple-Quantum-Well Light-Emitting Diodes

2003 ◽  
Vol 764 ◽  
Author(s):  
X. A. Cao ◽  
S. F. LeBoeuf ◽  
J. L. Garrett ◽  
A. Ebong ◽  
L. B. Rowland ◽  
...  
Keyword(s):  
Quantum Well ◽  
Light Emitting Diodes ◽  
Multiple Quantum Well ◽  
Light Output ◽  
Localized States ◽  
Multiple Quantum ◽  
Nonradiative Recombination ◽  
Light Emitting ◽  
Temperature Range ◽  
Green Leds

Absract:Temperature-dependent electroluminescence (EL) of InGaN/GaN multiple-quantum-well light-emitting diodes (LEDs) with peak emission energies ranging from 2.3 eV (green) to 3.3 eV (UV) has been studied over a wide temperature range (5-300 K). As the temperature is decreased from 300 K to 150 K, the EL intensity increases in all devices due to reduced nonradiative recombination and improved carrier confinement. However, LED operation at lower temperatures (150-5 K) is a strong function of In ratio in the active layer. For the green LEDs, emission intensity increases monotonically in the whole temperature range, while for the blue and UV LEDs, a remarkable decrease of the light output was observed, accompanied by a large redshift of the peak energy. The discrepancy can be attributed to various amounts of localization states caused by In composition fluctuation in the QW active regions. Based on a rate equation analysis, we find that the densities of the localized states in the green LEDs are more than two orders of magnitude higher than that in the UV LED. The large number of localized states in the green LEDs are crucial to maintain high-efficiency carrier capture at low temperatures.

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