A hybrid green light-emitting diode comprised of n-ZnO/(InGaN/GaN) multi-quantum-wells/p-GaN

In this study, we compared the device performance of GaInN-based green LEDs grown on c-plane sapphire substrates with a conventional low temperature GaN buffer layer to those with a sputtered-AlN buffer layer. The light output power and leakage current characteristics were significantly improved by just replacing the buffer layer with a sputtered-AlN layer. To understand the origin of the improvement in performance, the electrical and optical properties were compared by means of electro-reflectance spectroscopy, I–V curves, electroluminescence spectra, L–I curves, and internal quantum efficiencies. From the analysis of the results, we concluded that the improvement is mainly due to the mitigation of strain and reduction of the piezoelectric field in the multiple quantum wells active region.

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Development of High Power Green Light Emitting Diode Chips

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300000533 ◽

2005 ◽

Vol 10 ◽

Cited By ~ 22

Author(s):

Christian Wetzel ◽

T. Detchprobhm

Keyword(s):

Quantum Wells ◽

Light Emitting Diode ◽

Green Light ◽

High Yield ◽

Production Scale ◽

Light Emitting ◽

Force Microscopy ◽

Atomic Force ◽

High Emission ◽

Optimization Schemes

The development of high emission power green light emitting diodes chips using GaInN/GaN multi quantum well heterostructures on sapphire substrate in our group is being reviewed. We analyze the electronic bandstructure in highly polarized GaInN/GaN quantum wells to identify the appropriate device structures. We describe the optimization of the epitaxial growth for highest device performance. Applying several optimization schemes, we find that lateral smoothness and homogeneity of the active region as characterized by atomic force microscopy is a most telling character of high yield, high output power devices emitting near 525 nm. In un-encapsulated epi-up mounted (400 μm)2 die we achieve 2.5 mW at 20 mA at 525 nm. We describe die performance, wafer yield, and process stability, and reproducibility for our production-scale implementation of this green LED die process.

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Effect of Same-Temperature GaN Cap Layer on the InGaN/GaN Multiquantum Well of Green Light-Emitting Diode on Silicon Substrate

The Scientific World JOURNAL ◽

10.1155/2013/538297 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 3

Author(s):

Changda Zheng ◽

Li Wang ◽

Chunlan Mo ◽

Wenqing Fang ◽

Fengyi Jiang

Keyword(s):

Quantum Wells ◽

Light Emitting Diode ◽

Green Light ◽

Xrd Analysis ◽

Light Emitting ◽

Green Led ◽

Cap Layer ◽

Different Thickness ◽

Ingan Quantum Wells

GaN green LED was grown on Si (111) substrate by MOCVD. To enhance the quality of InGaN/GaN MQWs, same-temperature (ST) GaN protection layers with different thickness of 8 Å, 15 Å, and 30 Å were induced after the InGaN quantum wells (QWs) layer. Results show that a relative thicker cap layer is benefit to get InGaN QWs with higher In percent at fixed well temperature and obtain better QW/QB interface. As the cap thickness increases, the indium distribution becomes homogeneous as verified by fluorescence microscope (FLM). The interface of MQWs turns to be abrupt from XRD analysis. The intensity of photoluminescence (PL) spectrum is increased and the FWHM becomes narrow.

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n-type GaN surface etched green light-emitting diode to reduce non-radiative recombination centers

Applied Physics Letters ◽

10.1063/5.0035343 ◽

2021 ◽

Vol 118 (2) ◽

pp. 021102

Author(s):

Dong-Pyo Han ◽

Ryoto Fujiki ◽

Ryo Takahashi ◽

Yusuke Ueshima ◽

Shintaro Ueda ◽

...

Keyword(s):

Radiative Recombination ◽

Light Emitting Diode ◽

Green Light ◽

Light Emitting ◽

Recombination Centers

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Effects of green light emitting diode light during incubation and dietary organic macro and trace minerals during rearing on tibia characteristics of broiler chickens at slaughter age

Poultry Science ◽

10.1016/j.psj.2020.11.042 ◽

2020 ◽

Author(s):

B.C. Güz ◽

R. Molenaar ◽

I.C. de Jong ◽

B. Kemp ◽

M. van Krimpen ◽

...

Keyword(s):

Broiler Chickens ◽

Light Emitting Diode ◽

Green Light ◽

Trace Minerals ◽

Light Emitting ◽

Slaughter Age

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UV Emission Mechanisms in Quaternary AlInGaN Epilayers and Multiple Quantum Wells

MRS Proceedings ◽

10.1557/proc-722-k1.7 ◽

2002 ◽

Vol 722 ◽

Author(s):

Mee-Yi Ryu ◽

C. Q. Chen ◽

E. Kuokstis ◽

J. W. Yang ◽

G. Simin ◽

...

Keyword(s):

Quantum Wells ◽

Light Emitting Diode ◽

Chemical Vapor ◽

Excitation Power ◽

Multiple Quantum Wells ◽

Multiple Quantum ◽

Excitation Power Density ◽

Light Emitting ◽

Uv Emission ◽

Alloy Disorder

AbstractWe present the results on investigation and analysis of photoluminescence (PL) dynamics of quaternary AlInGaN epilayers and AlInGaN/AlInGaN multiple quantum wells (MQWs) grown by a novel pulsed metalorganic chemical vapor deposition (PMOCVD). The emission peaks in both AlInGaN epilayers and MQWs show a blueshift with increasing excitation power density. The PL emission of quaternary samples is attributed to recombination of carriers/excitons localized at band-tail states. The PL decay time increases with decreasing emission photon energy, which is a characteristic of localized carrier/exciton recombination due to alloy disorder. The obtained properties of AlInGaN materials grown by a PMOCVD are similar to those of InGaN. This indicates that the AlInGaN system is promising for ultraviolet applications such as the InGaN system for blue light emitting diode and laser diode applications.

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Control of Barrier Width in Perovskite Multiple Quantum Wells for High Performance Green Light–Emitting Diodes

Advanced Optical Materials ◽

10.1002/adom.201801575 ◽

2018 ◽

Vol 7 (3) ◽

pp. 1801575 ◽

Cited By ~ 15

Author(s):

Maotao Yu ◽

Chang Yi ◽

Nana Wang ◽

Liangdong Zhang ◽

Renmeng Zou ◽

...

Keyword(s):

Quantum Wells ◽

High Performance ◽

Light Emitting Diodes ◽

Green Light ◽

Multiple Quantum Wells ◽

Multiple Quantum ◽

Barrier Width ◽

Light Emitting

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Operando direct observation of spin-states and charge-trappings of blue light-emitting-diode materials in thin-film devices

Scientific Reports ◽

10.1038/s41598-020-75668-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Fumiya Osawa ◽

Kazuhiro Marumoto

Keyword(s):

Blue Light ◽

High Performance ◽

Density Functional ◽

Light Emitting Diode ◽

Green Light ◽

Spin States ◽

Light Emitting ◽

Full Color ◽

Color Displays ◽

Materials Used

Abstract Spin-states and charge-trappings in blue organic light-emitting diodes (OLEDs) are important issues for developing high-device-performance application such as full-color displays and white illumination. However, they have not yet been completely clarified because of the lack of a study from a microscopic viewpoint. Here, we report operando electron spin resonance (ESR) spectroscopy to investigate the spin-states and charge-trappings in organic semiconductor materials used for blue OLEDs such as a blue light-emitting material 1-bis(2-naphthyl)anthracene (ADN) using metal–insulator–semiconductor (MIS) diodes, hole or electron only devices, and blue OLEDs from the microscopic viewpoint. We have clarified spin-states of electrically accumulated holes and electrons and their charge-trappings in the MIS diodes at the molecular level by directly observing their electrically-induced ESR signals; the spin-states are well reproduced by density functional theory. In contrast to a green light-emitting material, the ADN radical anions largely accumulate in the film, which will cause the large degradation of the molecule and devices. The result will give deeper understanding of blue OLEDs and be useful for developing high-performance and durable devices.

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