scholarly journals Enhanced Internal Quantum Efficiency of Bandgap-Engineered Green W-Shaped Quantum Well Light-Emitting Diode

2018 ◽  
Vol 9 (1) ◽  
pp. 77 ◽  
Author(s):  
Muhammad Usman ◽  
Urooj Mushtaq ◽  
Dong-Guang Zheng ◽  
Dong-Pyo Han ◽  
Muhammad Rafiq ◽  
...  
Keyword(s):  
Quantum Well ◽  
Quantum Efficiency ◽  
Recombination Rate ◽  
Auger Recombination ◽  
Light Emitting Diode ◽  
Internal Quantum Efficiency ◽  
Green Light ◽  
Light Emitting ◽  
Hole Confinement ◽  
Electromechanical Field

To improve the internal quantum efficiency of green light-emitting diodes, we present the numerical design and analysis of bandgap-engineered W-shaped quantum well. The numerical results suggest significant improvement in the internal quantum efficiency of the proposed W-LED. The improvement is associated with significantly improved hole confinement due to the localization of indium in the active region, leading to improved radiative recombination rate. In addition, the proposed device shows reduced defect-assisted Shockley-Read-Hall (SRH) recombination rate as well as Auger recombination rate. Moreover, the efficiency rolloff in the proposed device is associated with increased built-in electromechanical field.

scholarly journals Internal quantum efficiency improvement of InGaN/GaN multiple quantum well green light-emitting diodes

2016 ◽  
Vol 24 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Q. Zhou ◽  
M. Xu ◽  
H. Wang
Keyword(s):  
Quantum Well ◽  
Quantum Efficiency ◽  
Light Emitting Diode ◽  
Internal Quantum Efficiency ◽  
Multiple Quantum Well ◽  
Visible Light Communication ◽  
Multiple Quantum ◽  
Internal Electric Field ◽  
Light Emitting ◽  
Green Led

In recent years, GaN-based light-emitting diode (LED) has been widely used in various applications, such as RGB lighting system, full-colour display and visible-light communication. However, the internal quantum efficiency (IQE) of green LEDs is significantly lower than that of other visible spectrum LED. This phenomenon is called “green gap”. This paper briefly describes the physical mechanism of the low IQE for InGaN/GaN multiple quantum well (MQW) green LED at first. The IQE of green LED is limited by the defects and the internal electric field in MQW. Subsequently, we discuss the recent progress in improving the IQE of green LED in detail. These strategies can be divided into two categories. Some of these methods were proposed to enhance crystal quality of InGaN/GaN MQW with high In composition and low density of defects by modifying the growth conditions. Other methods focused on increasing electron-hole wave function overlap by eliminating the polarization effect.

scholarly journals Study on Optical Properties and Internal Quantum Efficiency Measurement of GaN-based Green LEDs

2019 ◽  
Vol 9 (3) ◽  
pp. 383
Author(s):  
Boyang Lu ◽  
Lai Wang ◽  
Zhibiao Hao ◽  
Yi Luo ◽  
Changzheng Sun ◽  
...  
Keyword(s):  
Optical Properties ◽  
Quantum Efficiency ◽  
Light Emitting Diode ◽  
Internal Quantum Efficiency ◽  
Green Light ◽  
Excitation Power ◽  
Temperature Dependent ◽  
Light Emitting ◽  
Integrated Intensity ◽  
Calculation Results

In this paper, the optical properties of GaN-based green light emitting diode (LED) are investigated and the internal quantum efficiency (IQE) values are measured by temperature dependent photoluminescence (TDPL) and power dependent photoluminescence (PDPL) methods. The "S-shaped” shift of peak wavelength measured at different temperature disappears gradually and the spectra broadening can be observed with increasing excitation power. The IQE calculation results of TDPL, which use the integrated intensity measured at low temperature as unity, can be modified by PDPL in order to acquire more accurate IQE values.

Local internal quantum efficiency of a green light emitting InGaN/GaN quantum well

2011 ◽  
Vol 249 (3) ◽  
pp. 600-603 ◽  
Author(s):  
J. Danhof ◽  
U. T. Schwarz ◽  
T. Meyer ◽  
C. Vierheilig ◽  
M. Peter
Keyword(s):  
Quantum Well ◽  
Quantum Efficiency ◽  
Internal Quantum Efficiency ◽  
Green Light ◽  
Light Emitting
Sign in / Sign up

Export Citation Format

Share Document