Download or read book Fabrication of High Modulation Bandwidth GaN Based Light Emitting Diode and Analysis of Visible Light Communication Applications written by Kai-Chia Chen and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gallium Nitride Light emitting Diode Enabled Visible Light Communications written by Ricardo Xavier da Graça Ferreira and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on the development, measurement and application of novel micrometre-sized light emitting diodes (micro-LEDs) based on Gallium Nitride (GaN) for visible light communications (VLC) in both free-space and guided wave configurations. The goal is to set benchmarks for LED-based wireless optical communications. An overview of the field integrating research, industry and standards is presented.A top-down approach is taken with application requirements driving development of new micro-LEDs with simultaneously increased optical power and modulation bandwidth. This was achieved by mitigating two limitations, namely current crowding and mutual device heating.Two novel techniques were developed to access pixel performance: spatially-resolved mapping of modulation bandwidth and spectral characteristics, and thermal imaging. On this basis, broad-area LEDs were used to understand the independent benefits, providing insight for the design of novel micro-LEDs. Circular segmented micro-LEDs emitting at 450nm achieved modulation bandwidths in excess of 800MHz, the highest reported for LEDs, while maintaining optical power above 2mW. In data transmission using systems with 1.8GHz bandwidth,the devices achieved 8Gbps in free-space and guided-wave operation at wavelengths of 400nm, 450nm and 520nm. Ring and half-ring micro-LEDs introduced here have shown modulation bandwidths that scale with the increase of active area and consequently optical power. Bandwidths in excess of of 600MHz were achieved at optical powers over 5mW. In data transmission using a system limited to 1GHz bandwidth, these devices achieved 7Gbps in free-space operation.
Download or read book High speed Gan based Photonic Crystal Light emitting Diodes for Visible Light Communication Applications written by 林東慶 and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Progress and Prospects of GaN based LEDs Using Nanostructures Project Supported by the National Natural Science Foundation of China Grant No 61334009 the National High Technology Research and Development Program of China Grant Nos 2015AA03A101 and 2014BAK02B08 China International Science and Technology Cooperation Program Grant No 2014DFG62280 the Import Outstanding Technical Talent Plan and Youth Innovation Promotion Association Program of the Chinese Academy of Sciences written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Progress with GaN-based light emitting diodes (LEDs) that incorporate nanostructures is reviewed, especially the recent achievements in our research group. Nano-patterned sapphire substrates have been used to grow an AlN template layer for deep-ultraviolet (DUV) LEDs. One efficient surface nano-texturing technology, hemisphere-cones-hybrid nanostructures, was employed to enhance the extraction efficiency of InGaN flip-chip LEDs. Hexagonal nanopyramid GaN-based LEDs have been fabricated and show electrically driven color modification and phosphor-free white light emission because of the linearly increased quantum well width and indium incorporation from the shell to the core. Based on the nanostructures, we have also fabricated surface plasmon-enhanced nanoporous GaN-based green LEDs using AAO membrane as a mask. Benefitting from the strong lateral SP coupling as well as good electrical protection by a passivation layer, the EL intensity of an SP-enhanced nanoporous LED was significantly enhanced by 380%. Furthermore, nanostructures have been used for the growth of GaN LEDs on amorphous substrates, the fabrication of stretchable LEDs, and for increasing the 3-dB modulation bandwidth for visible light communication.
Download or read book Principles of LED Light Communications written by Svilen Dimitrov and published by Cambridge University Press. This book was released on 2015-03-12 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Learn how to build efficient, simple, high performance indoor optical wireless communication systems based on visible and infrared light.
Download or read book LED Based Visible Light Communications written by Nan Chi and published by Springer. This book was released on 2018-09-01 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book systematically introduces the visible light communication (VLC) technology in detail. Basic concepts and how to realize the system are both illustrated, including the transmitter, channel, and the receiver. In addition, a good many experimental results are presented to help readers further understand the VLC technologies. The upper-layer protocols of visible light communication system and the technology trends are also discussed. This book can be a good reference work for researchers, engineers, and graduate students in the fields of communications, LED, and optics.
Download or read book Diode Lasers and Photonic Integrated Circuits written by Larry A. Coldren and published by John Wiley & Sons. This book was released on 2012-03-02 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diode Lasers and Photonic Integrated Circuits, Second Edition provides a comprehensive treatment of optical communication technology, its principles and theory, treating students as well as experienced engineers to an in-depth exploration of this field. Diode lasers are still of significant importance in the areas of optical communication, storage, and sensing. Using the the same well received theoretical foundations of the first edition, the Second Edition now introduces timely updates in the technology and in focus of the book. After 15 years of development in the field, this book will offer brand new and updated material on GaN-based and quantum-dot lasers, photonic IC technology, detectors, modulators and SOAs, DVDs and storage, eye diagrams and BER concepts, and DFB lasers. Appendices will also be expanded to include quantum-dot issues and more on the relation between spontaneous emission and gain.
Download or read book Fabrication and Analysis of GaN Based High Speed Blue Light Emitting Diodes written by 蕭佳晏 and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of Gallium Nitride based Ultraviolet and Visible Light emitting Diodes Using Hydride Vapor phase Epitaxy and Molecular Epitaxy written by Jasper Sicat Cabalu and published by . This book was released on 2006 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Much of the work done on ultraviolet (UV) and visible III-Nitrides-based light emitting diodes (LEDs) involves growth by metal-organic chemical vapor deposition (MOCVD). In this dissertation, the growth, development, and fabrication of III-Nitrides-based UV and visible LEDs with very high photon conversion and extraction efficiencies using hydride vapor-phase epitaxy (HVPE) and radio frequency (rf) plasma-assisted molecular beam epitaxy (PAMBE) is presented. High-power electrically-pumped UV-LEDs based on GaN/AlGaN multiple quantum wells (MQWs) emitting at 340 nm and 350 nm have been fabricated in a flip-chip configuration and evaluated. Under pulsed operation, UV-LEDs emitting at 340 nm have output powers that saturate, due to device heating, at approximately 3 mW. Devices emitting at 350 nm show DC operation output powers as high as 4.5 mW under 200 mA drive current. These results were found to be equivalent with those of UV-LEDs produced by the MOCVD and HVPE methods. The concept of using textured MQWs on UV-LED structures was tested by optical pumping of GaN/AlGaN MQWs grown on textured GaN templates. Results show highly enhanced (>700 times) blue-shifted photoluminescence (PL) at 360 nm compared to similarly produced MQWs on smooth GaN templates whose PL emission is red-shifted. These results are attributed partly to enhancement in light extraction efficiency (LEE) and partly to enhancement in internal quantum efficiency (IQE). The origin of the increase in IQE is partly due to reduction of the quantum-confined Stark effect (QCSE) on QW-planes not perpendicular to the polarization direction and partly due to charge redistribution in the QWs caused by the polarization component parallel to the planes of the QWs. Similar studies have been done for visible LEDs using InGaN/GaN MQWs. Growth of LED structures on textured GaN templates employing textured MQW-active regions resulted in the production of dichromatic (430 nm and 530 nm) phosphorless white LEDs with good electrical characteristics. We attribute this behavior to different incorporation of In in different QW-planes. These studies show that textured MQW-based LEDs not only offers the benefit of enhanced IQE and LEE, but also the benefit of producing efficient white LEDs without the use of phosphor.
Download or read book Perovskite Quantum Dots written by Ye Zhou and published by Springer Nature. This book was released on 2020-08-27 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses perovskite quantum dots, discussing their unique properties, synthesis, and applications in nanoscale optoelectronic and photonic devices, as well as the challenges and possible solutions in the context of device design and the prospects for commercial applications. It particularly focuses on the luminescent properties, which differ from those of the corresponding quantum dots materials, such as multicolor emission, fluorescence narrowing, and tunable and switchable emissions from doped nanostructures. The book first describes the characterization and fabrication of perovskite quantum dots. It also provides detailed methods for analyzing the electrical and optical properties, and demonstrates promising applications of perovskite quantum dots. Furthermore, it presents a series of optoelectronic and photonic devices based on functional perovskite quantum dots, and explains the incorporation of perovskite quantum dots in semiconductor devices and their effect of the performance. It also explores the challenges related to optoelectronic devices, as well as possible strategies to promote their commercialization. As such, this book is a valuable resource for graduate students and researchers in the field of solid-state materials and electronics wanting to gain a better understanding of the characteristics of quantum dots, and the fundamental optoelectronic properties and operation mechanisms of the latest perovskite quantum dot-based devices.
Download or read book Fabrication and Analysis of Light Transmittance Through Roughened Surfaces of Transparent Materials and Its Application in GaN based Light emitting Diodes written by Xiaolu Li and published by . This book was released on 2005 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optoelectronic Devices written by M Razeghi and published by Elsevier. This book was released on 2004 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tremendous progress has been made in the last few years in the growth, doping and processing technologies of the wide bandgap semiconductors. As a result, this class of materials now holds significant promis for semiconductor electronics in a broad range of applications. The principal driver for the current revival of interest in III-V Nitrides is their potential use in high power, high temperature, high frequency and optical devices resistant to radiation damage. This book provides a wide number of optoelectronic applications of III-V nitrides and covers the entire process from growth to devices and applications making it essential reading for those working in the semiconductors or microelectronics. Broad review of optoelectronic applications of III-V nitrides
Download or read book Fabrication and Analysis of Resolution 1920 1080 with 5 CEBCm GaN based Micro Light Emitting Diodes for High Resolution Display Applications written by 王柏翔 and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fabrication and Analysis of GaN based Nanorod Light Emitting Diodes written by 王振印 and published by . This book was released on 2008 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gan based Materials And Devices Growth Fabrication Characterization And Performance written by Robert F Davis and published by World Scientific. This book was released on 2004-05-07 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: The unique materials properties of GaN-based semiconductors have stimulated a great deal of interest in research and development regarding nitride materials growth and optoelectronic and nitride-based electronic devices. High electron mobility and saturation velocity, high sheet carrier concentration at heterojunction interfaces, high breakdown field, and low thermal impedance of GaN-based films grown over SiC or bulk AlN substrates make nitride-based electronic devices very promising. The chemical inertness of nitrides is another key property.This volume, written by experts on different aspects of nitride technology, addresses the entire spectrum of issues related to nitride materials and devices, and it will be useful for technologists, scientists, engineers, and graduate students who are working on wide bandgap materials and devices. The book can also be used as a supplementary text for graduate courses on wide bandgap semiconductor technology.
Download or read book Investigation and Fabrication of GaN based Blue Light Emitting Diode with High Light Extraction and Quantum Efficiency written by and published by . This book was released on 2015 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design and Fabrication of High Efficiency GaN Based Light Emitting Diodes written by 汪楷茗 and published by . This book was released on 2006 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
