Formation mechanism of V defects in the InGaN/GaN multiple quantum wells grown on GaN layers with low threading dislocation density

2001 ◽  
Vol 79 (2) ◽  
pp. 215-217 ◽  
Author(s):  
H. K. Cho ◽  
J. Y. Lee ◽  
G. M. Yang ◽  
C. S. Kim
Keyword(s):  
Dislocation Density ◽  
Quantum Wells ◽  
Formation Mechanism ◽  
Multiple Quantum Wells ◽  
Multiple Quantum ◽  
Threading Dislocation ◽  
Threading Dislocation Density

Preparation of Substrates Intended for the Growth of Lower Threading Dislocation Densities within Nitride Based UV Multiple Quantum Wells

2013 ◽  
Vol 53 (2) ◽  
pp. 39-42 ◽  
Author(s):  
M. A. Conroy ◽  
N. Petkov ◽  
H. N. Li ◽  
T. C. Sadler ◽  
V. Zubialevich ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Multiple Quantum Wells ◽  
Multiple Quantum ◽  
Threading Dislocation ◽  
Dislocation Densities

The effects of varying threading dislocation density on the optical properties of InGaN/GaN quantum wells

2014 ◽  
Vol 11 (3-4) ◽  
pp. 750-753 ◽  
Author(s):  
Matthew J. Davies ◽  
Philip Dawson ◽  
Fabien C.-P. Massabuau ◽  
Fabrice Oehler ◽  
Rachel A. Oliver ◽  
...  
Keyword(s):  
Optical Properties ◽  
Dislocation Density ◽  
Quantum Wells ◽  
Threading Dislocation ◽  
Threading Dislocation Density

Effect of Interface Roughness and Dislocation Density on Electroluminescence Intensity of InGaN Multiple Quantum Wells

2008 ◽  
Vol 25 (11) ◽  
pp. 4143-4146 ◽  
Author(s):  
Zhao De-Gang ◽  
Jiang De-Sheng ◽  
Zhu Jian-Jun ◽  
Liu Zong-Shun ◽  
Zhang Shu-Ming ◽  
...  
Keyword(s):  
Dislocation Density ◽  
Quantum Wells ◽  
Interface Roughness ◽  
Multiple Quantum Wells ◽  
Multiple Quantum ◽  
Electroluminescence Intensity

Effect of trimethylgallium flow on the structural and optical properties of InGaN/GaN multiple quantum wells

2004 ◽  
Vol 37 (3) ◽  
pp. 391-394 ◽  
Author(s):  
J. C. Zhang ◽  
J. F. Wang ◽  
Y. T. Wang ◽  
M. Wu ◽  
J. P. Liu ◽  
...  
Keyword(s):  
Optical Properties ◽  
Dislocation Density ◽  
Quantum Wells ◽  
Chemical Vapour ◽  
Interface Roughness ◽  
Multiple Quantum Wells ◽  
Structural Defects ◽  
Organic Chemical ◽  
Multiple Quantum ◽  
Edge Dislocations

InGaN/GaN multiple quantum wells (MQWs) are grown by metal-organic chemical vapour deposition on (0001) sapphire substrates. Triple-axis X-ray diffraction (TXRD) and photoluminescence (PL) spectra are used to assess the influence of trimethylgallium (TMGa) flow on structural defects, such as dislocations and interface roughness, and the optical properties of the MQWs. In this paper, a method, involving an ω scan of every satellite peak of TXRD, is presented to measure the mean dislocation density of InGaN/GaN MQWs. The experimental results show that under certain conditions which keep the trimethlyindium flow constant, dislocation density and interface roughness decrease with the increase of TMGa flow, which will improve the PL properties. It can be concluded that dislocations, especially edge dislocations, act as non-radiative recombination centres in InGaN/GaN MQWs. Also noticed is that changing the TMGa flow has more influence on edge dislocations than screw dislocations.

Characterization of InGaN/GaN Multiple Quantum Wells Grown on Sapphire Substrates by Nano-scale Epitaxial Lateral Overgrowth Technique

2011 ◽  
Vol 1288 ◽  
Author(s):  
W.K. Fong ◽  
K.K. Leung ◽  
Charles Surya
Keyword(s):  
Quantum Wells ◽  
Internal Quantum Efficiency ◽  
Average Diameter ◽  
Control Device ◽  
Multiple Quantum Wells ◽  
Epitaxial Lateral Overgrowth ◽  
Multiple Quantum ◽  
Threading Dislocation ◽  
Nano Scale ◽  
Proposed Model

ABSTRACTHigh-quality InGaN/GaN multiple quantum wells (MQWs) were fabricated on nano-scale epitaxial lateral overgrown (NELO) GaN layers which was prepared using nanometer-scale SiO2 islands, with an average diameter and interdistance of 300nm and 200nm respectively, as the growth mask. The active region of the device consists of five periods of GaN/InGaN MQWs were grown on top of the NELO layer using MOCVD technique. It is observed that some of the dislocations from the undoped GaN were blocked by the SiO2 growth mask and typical threading dislocation (TD) density found in the NELO samples is ~7.5×107cm-2. Significant improvement in the electroluminescence (EL) is observed which is believed to partly arise from the improvement in the internal quantum efficiency (ηi). The experimental data on the temperature dependence of the photoluminescence (PL) were fitted to a proposed model using Levenberg-Marquardt approximation. Based on our analyses it is found that the relative improvement in ηi at 300K over a control device grown in the same growth condition but without the NELO layer to a NELO device is only 0.59. It is generally accepted that TD is the non-radiative recombination center which affects the IQE. Therefore, room-temperature IQE values also support that NELO device exhibits lower TD density.

High Efficiency Uv Emitter Using High Quality GaN/AlxGa1−xN Multi-Quantum Well Active Layer

2000 ◽  
Vol 639 ◽  
Author(s):  
M. Iwaya ◽  
S. Terao ◽  
T. Ukai ◽  
R. Nakamura ◽  
S. Kamiyama ◽  
...  
Keyword(s):  
Dislocation Density ◽  
Quantum Wells ◽  
High Efficiency ◽  
Light Emitting Diode ◽  
Threading Dislocation ◽  
Light Emitting ◽  
Si Doping ◽  
Threading Dislocation Density ◽  
Pl Intensity ◽  
Multi Quantum Well

ABSTRACTWe investigated temperature dependence of the photoluminescence (PL) efficiency of GaN/Al0.08Ga0.92N multi-quantum wells (MQWs) with variations of Si-doping condition and threading dislocation density. Si-doping in the GaN/Al0.08Ga0.92N MQWs, especially in the barrier layer improves the PL efficiency. In addition, reduction of threading dislocation density also improves the PL intensity. The PL intensity of the GaN/Al0.08Ga0.92N MQW is drastically increased at least by a factor of 40, by a combination of the Si-doping and reduction of threading dislocation density. We fabricated a light emitting diode (LED) emitting at 357 nm using such a GaN/Al0.08Ga0.92N MQWs. Electro-luminescence intensity from the region with threading dislocation density of less than 108 cm−2 was much larger than that from the region with threading dislocation density of 6×109 cm−2.

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