A5020745634- GaN-based semiconductor devices and materials
- Ga2O3 and related materials
- ZnO doping and properties
- Semiconductor Quantum Structures and Devices
- Metal and Thin Film Mechanics
- Semiconductor materials and devices
- Photocathodes and Microchannel Plates
- Chemical Synthesis and Reactions
- Nanowire Synthesis and Applications
- Oxidative Organic Chemistry Reactions
- Plasma Diagnostics and Applications
- Synthesis and Catalytic Reactions
- Silicon Carbide Semiconductor Technologies
- Gas Sensing Nanomaterials and Sensors
- Synthetic Organic Chemistry Methods
- Semiconductor Lasers and Optical Devices
- Plasmonic and Surface Plasmon Research
- Advanced Photocatalysis Techniques
- Gold and Silver Nanoparticles Synthesis and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Asymmetric Synthesis and Catalysis
- Acoustic Wave Resonator Technologies
- Thermal properties of materials
- Hip and Femur Fractures
- Atmospheric Ozone and Climate
King Abdullah University of Science and Technology
2017-2025
Eisai (Japan)
2012-2024
Chiba University
2020-2023
Hamamatsu Photonics (Japan)
2023
Teikyo University Chiba Medical Center
2022-2023
Teikyo University
2022
Bridge University
2021
National Taipei University
2021
National Chung Hsing University
2021
University of Science and Technology
2021
In this research, five sizes (100 × 100, 75 75, 50 50, 25 25, 10 µm2) of InGaN red micro-light emitting diode (LED) dies are produced using laser-based direct writing and maskless technology. It is observed that with increasing injection current, the smaller size micro-LED, more obvious blue shift emission wavelength. When current increased from 0.1 to 1 mA, wavelength μm2 micro-LED shifted 617.15 576.87 nm. The attributed stress release high density injection. Moreover, output power very...
Abstract Micro light-emitting diode (micro-LED) will play an important role in the future generation of smart displays. They are found very attractive many applications, such as maskless lithography, biosensor, augmented reality (AR)/mixed etc, at same time. A monitor that can fulfill saturated color rendering, high display resolution, and fast response time is highly desirable, micro-LED-based technology could be our best chance to meet these requirements. At present, semiconductor-based...
This work investigates the influence of residual stress on performance InGaN-based red light-emitting diodes (LEDs) by changing thickness underlying n-GaN layers. The in-plane in LED structure depends layer. Decreased resulting from increased layers improves crystalline quality InGaN active region allowing for a higher growth temperature. electroluminescence intensity LEDs is factor 1.3 when layer 2 to 8 μm. Using 8-μm-thick layers, 633-nm-wavelength are realized with light-output power 0.64...
Abstract Here we report InGaN-based red light-emitting diodes (LEDs) grown on ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mn>2</mml:mn> <mml:mo stretchy="true">¯</mml:mo> </mml:mover> <mml:mn>01</mml:mn> </mml:math> ) β -Ga 2 O 3 substrates. AlN/AlGaN strain-compensating layers and hybrid multiple-quantum-well structures were employed to improve the crystalline-quality of InGaN active region. A bare LED showed that peak wavelength, light...
Abstract InGaN-based LEDs are efficient light sources in the blue–green range and have been successfully commercialized last decades. Extending their spectral to red region causes a significant reduction LED efficiency. This challenge hinders integration of red, green, blue based on III-nitride materials, especially for full-color micro-LED displays. We review our recent progress with different chip sizes from hundreds tens micrometers, including epitaxial structures, device fabrication,...
We investigated the performance of InGaN-based red/green micro-light-emitting diodes (µLEDs) ranging from <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>98</mml:mn> </mml:mrow> <mml:mo>×<!-- × --></mml:mo> <mml:mspace width="thickmathspace" /> <mml:msup> <mml:mtext>µ<!-- µ --></mml:mtext> <mml:mi mathvariant="normal">m</mml:mi> <mml:mn>2</mml:mn> </mml:msup> </mml:math> to <mml:mn>17</mml:mn> . The average forward voltage...
Abstract GaN-based light-emitting devices have the potential to realize all visible emissions with same material system. These emitters are expected be next-generation red, green, and blue displays illumination tools. emitting been realized highly efficient green diodes (LEDs) laser diodes. Extending them longer wavelength remains challenging from an efficiency perspective. In emerging research field of micro-LED displays, III-nitride red LEDs in high demand establish like conventional...
In this study, we present a high-efficiency InGaN red micro-LED fabricated by the incorporation of superlattice structure, atomic layer deposition passivation, and distributed Bragg reflector, exhibiting maximum external quantum efficiency 5.02% with low droop corresponding to an injection current density <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="m1"> <mml:mrow> <mml:mn>112</mml:mn> <mml:mtext> </mml:mtext> <mml:msup> <mml:mi...
Here, we report highly efficient InGaN-based red light-emitting diodes (LEDs) grown on conventional c-plane-patterned sapphire substrates. An InGaN single quantum well active layer provides the spectral emission. The 621-nm-wavelength LEDs exhibited high-purity emission with a narrow full-width at half-maximum of 51 nm. packaged LED’s external efficiency, light-output power, and forward voltage 621 nm peak wavelength 20 mA (10.1 A/cm2) injection current were 4.3%, 1.7 mW, 2.96 V,...
High-performance GaInN-based solar cells with high open-circuit voltage, short-circuit current density, and good fill factor have been obtained using a combination of two different GaInN superlattice structures. The barrier thicknesses (3 0.6 nm) in both structures were optimized, resulting thick active layer low pit density the device. conversion efficiency is approximately 2.5% under simulator air mass 1.5G an irradiation intensity 155 mW/cm2.
Abstract We demonstrate the effectiveness of a hybrid multiple-quantum-wells (MQWs) structure in InGaN-based orange light-emitting diodes (LEDs) grown by metalorganic vapor phase epitaxy. The MQWs-LED is composed InGaN double QWs and blue-green single QW. Using MQWs structure, LEDs exhibited electroluminescence spectra with narrow full widths at half maximum 51 nm 20 mA. light output power external quantum efficiency were 0.23 mW 0.6%, respectively,
We demonstrated amber InGaN <inline-formula> <tex-math notation="LaTeX">$47\times 47\,\,\mu \text{m}^{{2}}$ </tex-math></inline-formula> micro-light-emitting diodes (<inline-formula> notation="LaTeX">$\mu $ </tex-math></inline-formula>LEDs) with the peak wavelength of 606 nm and full-width at maximum (FWHM) 50 20 A/cm<sup>2</sup>. The </tex-math></inline-formula>LEDs exhibited a 33-nm blue-shift obtain broader FWHMs to approximately 56 5 100 on-wafer external quantum efficiency was...
Abstract We investigated the effect of sidewall passivation by hydrogen plasma on InGaN green micro-LED performance. Hydrogen deactivates surface region p-GaN around perimeter device mesa. Thus, hole injection is suppressed in this region, where etching-caused material degradation results leakage current, decreasing efficiency. have confirmed LED square pixels with sizes 20 and 100 μ m. For smaller LEDs, reverse current has reduced more than tenfold, external quantum efficiency LEDs was...
Abstract We report a 330 ppi monolithic RGB micro light-emitting diodes ( μ LED) array of blue, green and red GaInN-based LEDs stacked on the same wafer. Considering it is challenging to form ohmic electrodes plasma-etched p-type GaN surface, tunnel junctions were used connect each LED, anode for blue formed n-type AlGaN. The fabricated LED arrays tested at room temperature (approximately 26 °C) DC. Each emitted with peak wavelengths 486, 514 604 nm current density 50 A cm −2 .
In this study, we have demonstrated the potential of InGaN-based red micro-LEDs with single quantum well (SQW) structure for visible light communication applications. Our findings indicate SQW sample has a better crystal quality, high-purity emission, narrower full width at half maximum, and higher internal efficiency, compared to InGaN micro-LED double wells (DQWs) structure. The exhibits maximum external efficiency 5.95% experiences less blueshift as current density increases when DQWs...
We study the impact of strain engineering by exploring influence number superlattice (SL) layers underneath InGaN/GaN multiple quantum wells (MQWs) on optical properties InxGa1–xN/GaN MQWs grown patterned sapphire metal–organic chemical vapor deposition while retaining same composition and MQW periods. X-ray diffraction reciprocal space mapping show that initially increases with SLs in structure followed a slight relaxation. Scanning electron microscopy analysis indicates desired is obtained...
We investigated the effects of size on electrical and optical properties InGaN-based red light-emitting diodes (LEDs) by designing rectangular chips with different mesa lengths. Larger exhibited lower forward voltages because their series resistances. A larger chip helped to realize a longer emission wavelength, narrower full-width at half maximum, higher external quantum efficiency. However, temperature-dependent electroluminescence measurements indicated that are detrimental applications...
We demonstrated <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="m1"> <mml:mrow> <mml:mn>10</mml:mn> <mml:mo>×</mml:mo> </mml:mrow> </mml:math> arrays of InGaN id="m2"> <mml:mn>17</mml:mn> <mml:mtext> </mml:mtext> <mml:mi>μm</mml:mi> micro-light-emitting diodes (μLEDs) with a peak wavelength from 662 to 630 nm at id="m3"> <mml:mi>–</mml:mi> <mml:mn>50</mml:mn> <mml:mi mathvariant="normal">A</mml:mi> <mml:mo>/</mml:mo> <mml:msup> <mml:mi>cm</mml:mi>...
E7130 is a novel drug candidate with an exceedingly complex chemical structure of the halichondrin class, discovered by total synthesis approach through joint research between Kishi group at Harvard University and Eisai. Only 18 months after completion initial milligram-scale synthesis, ten-gram-scale was achieved, providing first good manufacturing practice (GMP) batch to supply clinical trials. This paper highlights challenges in developing from synthesis.
Process development of E7130 Drug Substance, which is a novel anticancer drug candidate, described. To accomplish rapid delivery such large and structurally complex substance for first-in-human (FIH) clinical trial, close collaboration among medicinal chemistry, process academia teams was required. The successful establishment suitable synthetic route in concise time frame while negotiating challenging chemical reactions (e.g., asymmetric catalytic Nozaki–Hiyama–Kishi (NHK) reaction...
In state-of-the-art red InGaN light-emitting diodes (LEDs), an InGaN-based blue single quantum well (SQW) is used as underlying layer to improve the emission efficiency. However, role of SQW not fully understood. This study investigates structural and optical properties by atomic force microscopy (AFM) photoluminescence (PL) spectroscopy under scanning near-field (SNOM). The AFM images reveal deep shallow V-pits, corresponding screw mixed threading dislocations (TDs). SNOM-PL intensity image...