Download or read book Growth and Morphology of Er Doped GaN on Sapphire and Hydride Vapor Phase Epitaxy Substrates written by and published by . This book was released on 1999 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the morphological and compositional characteristics and their effect on optical properties of Er-doped GaN grown by solid source molecular beam epitaxy on sapphire and hydride vapor phase epitaxy GaN substrates. The GaN was grown by molecular beam epitaxy on sapphire substrates using solid sources (for Ga, Al, and Er) and a plasma gas source for N2. The emission spectrum of the GaN:Er films consists of two unique narrow green lines at 537 and 558 nm along with typical Er31 emission in the infrared at 1.5 micrometers. The narrow lines have been identified as Er31 transitions from the 2H(sub 11/2) and 4S(sub 3/2) levels to the 4I(sub 15/2) ground state. The morphology of the GaN:Er films showed that the growth resulted in either a columnar or more compact structure with no effect on green light emission intensity.
Download or read book Characterization of Hydride Vapor Phase Epitaxy Grown GaN Substrates for Future III nitride Growth written by Alaa Ahmad Kawagy and published by . This book was released on 2019 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this research is to investigate and characterize the quality of commercially obtained gallium nitride (GaN) on sapphire substrates that have been grown using hydride vapor phase epitaxy (HVPE). GaN substrates are the best choice for optoelectronic applications because of their physical and electrical properties. Even though HVPE GaN substrates are available at low-cost and create the opportunities for growth and production, these substrates suffer from large macro-scale defects on the surface of the substrate. In this research, four GaN on sapphire substrates were investigated in order to characterize the surface defects and, subsequently, understand their influence on homoepitaxial GaN growth. Two substrates were unintentionally doped (UID) GaN on sapphire, and the other two were semi-insulating (SI) GaN on sapphire which were doped with iron (Fe) in order to compensate the background doping inherent in GaN. Several characterization techniques were performed. Atomic force microscopy, scanning electron microscopy, and optical microscopy were performed to characterize the surface morphology. X-ray diffraction, cathodoluminescence, transmission measurements, and optical transmission electron microscopy were applied to study the bulk structural and optical properties. The investigation of the surface of GaN substrates exposed various defects that are associated with defects in the structure such as dislocations, as well as vacancies and point defects. The UID GaN substrates suffered from hexagonal V-shape pits with pits densities of approximately 107 and 108 cm-2, whereas, the SI GaN substrates exhibited much larger macro-scale pits with areal densities of about 102 cm-2. X-ray diffraction results were deconvoluted in order to characterize the screw and mixed (edge and screw) dislocation densities for the studied substrates. The UID substrates exhibited screw dislocation densities of 107 and 108 cm-2 and mixed dislocation densities of 109 and 1010 cm-2. The SI substrates, however, exhibit generally lower densities of dislocations of 109 and 108 cm-2 for screw and mixed, respectively. Cathodoluminescence measurements demonstrated interesting results for the UID and SI substrates with energies of 4 and 3.5 eV, respectively. The transmission measurements for the UID substrates showed that the bandgap energy was 3.39 eV.
Download or read book The Lincoln Laboratory Journal written by and published by . This book was released on 2000 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 2240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nitride Semiconductor Light Emitting Diodes LEDs written by Jian-Jang Huang and published by Woodhead Publishing. This book was released on 2017-10-24 with total page 826 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitride Semiconductor Light-Emitting Diodes (LEDs): Materials, Technologies, and Applications, Second Edition reviews the fabrication, performance and applications of the technology, encompassing the state-of-the-art material and device development, along with considerations regarding nitride-based LED design. This updated edition is based on the latest research and advances, including two new chapters on LEDs for large displays and laser lighting. Chapters cover molecular beam epitaxy (MBE) growth of nitride semiconductors, modern metalorganic chemical vapor deposition (MOCVD) techniques, the growth of nitride-based materials, and gallium nitride (GaN)-on-sapphire and GaN-on-silicon technologies for LEDs. Nanostructured, non-polar and semi-polar nitride-based LEDs, as well as phosphor-coated nitride LEDs, are also discussed. The book also addresses the performance of nitride LEDs, including photonic crystal LEDs, surface plasmon enhanced LEDs, color tuneable LEDs, and LEDs based on quantum wells and quantum dots. Further chapters discuss the development of LED encapsulation technology and fundamental efficiency droop issues in gallium indium nitride (GaInN) LEDs. It is a technical resource for academics, physicists, materials scientists, electrical engineers, and those working in the lighting, consumer electronics, automotive, aviation, and communications sectors. Features new chapters on laser lighting, addressing the latest advances on this topic Reviews fabrication, performance, and applications of this technology that encompass the state-of-the-art material and device development Covers the performance of nitride LEDs, including photonic crystal LEDs, surface plasmon enhanced LEDs, color tuneable LEDs, and LEDs based on quantum wells and quantum dots Highlights applications of nitride LEDs, including liquid crystal display (LCD) backlighting, infra-red emitters, and automotive lighting Provides a comprehensive discussion of gallium nitride on both silicon and sapphire substrates
Download or read book Hydride Vapor Phase Epitaxy Growth of GaN InGaN ScN and ScAIN written by and published by . This book was released on 2010 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technology of Gallium Nitride Crystal Growth written by Dirk Ehrentraut and published by Springer Science & Business Media. This book was released on 2010-06-14 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the important technological aspects of the growth of GaN single crystals by HVPE, MOCVD, ammonothermal and flux methods for the purpose of free-standing GaN wafer production.
Download or read book Growth of GaN by Hydride Vapor Phase Epitaxy written by Volker Wagner and published by . This book was released on 2001 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heteroepitaxial Growth of GaN Nanostructures Via Metalorganic Vapor Phase Epitaxy on Sapphire and Silicon Using Graphene as Buffer Layer written by Martin Heilmann 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 A1GaN GaN HEMTs Grown by Molecular Beam Epitaxy on Sapphire SiC and HVPE GaN Templates written by Nils G. Weimann and published by . This book was released on 2002 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular Beam Epitaxy of GaN and related alloys is becoming a rival to the more established Metalorganic Vapor Phase Epitaxy. Excellent control of impurity, interface abruptness, and in- situ monitoring of the growth are driving the increase in quality of MBE epilayers. We have developed nucleation schemes with plasma-assisted MBE on three types of substrates, consisting of sapphire, semi-insulating (SI- ) SiC, and HVPE SI-GaN templates on sapphire. While sapphire and SI-SiC are established substrates for the growth of AlGaN/GaN HEMT epilayers, HVPE GaN templates may provide a path to low-cost large-diameter substrates for electronic devices. We compare device results of HEMTs fabricated on these substrates. As a metric for device performance, the saturated RF power output in class A operation is measured at 2 GHz. We achieved a saturated power density of 2.2 W/mm from HEMTs on sapphire, 1.1 W/mm from HEMTs on HVPE GaN templates on sapphire, and 6.3 W/mm from HEMTs on semi-insulating 611-SiC substrates. The difference in output power can be attributed to self-heating due to insufficient thermal conductivity of the sapphire substrate, and to trapping in the compensation- doped HVPE template.
Download or read book Structural and Morphological Investigation of Non basal plane GaN by Vapor Phase Epitaxy with a Special Emphasis on Nonpolar M plane written by Asako Hirai and published by . This book was released on 2009 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, heteroepitaxy and homoepitaxy of nonpolar m-plane GaN were extensively studied. For the growth methods, two of the major GaN vapor phase epitaxy techniques, i.e. hydride vapor phase epitaxy (HVPE) and metal organic chemical vapor deposition (MOCVD) were employed. Numerous characterization techniques were used to analyze the surface morphology and structural quality.
Download or read book Growth of GaN on Pre patterned Substrates by Vapor Phase Epitaxy for Optoelectronic Applications written by Kyung-Jun Nam and published by . This book was released on 1998 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book GaN Substrate and GaN Homo epitaxy for LEDs Progress and Challenges Project Supported by the National High Technology Research and Development Program of China Grant No 2014AA032605 the National Key Basic Research and Development Program of China Grant Nos 2012CB619304 and 2011CB301904 and the National Natural Science Foundation of China Grant Nos 61376012 61474003 and 61327801 written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: After a brief review on the progresses in GaN substrates by ammonothermal method and Na-flux method and hydride vapor phase epitaxy (HVPE) technology, our research results of growing GaN thick layer by a gas flow-modulated HVPE, removing the GaN layer through an efficient self-separation process from sapphire substrate, and modifying the uniformity of multiple wafer growth are presented. The effects of surface morphology and defect behaviors on the GaN homo-epitaxial growth on free standing substrate are also discussed, and followed by the advances of LEDs on GaN substrates and prospects of their applications in solid state lighting.
Download or read book Modulated Growth of Thick GaN Layers with Hydride Vapor Phase Epitaxy HVPE written by Wei Zhang and published by . This book was released on 2001 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Extracts from the Alpine Journal and Other Periodicals Referring to the Mountaineering Exploits of H B de Saussure written by and published by . This book was released on 1787 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Directory of Graduate Research written by and published by . This book was released on 2001 with total page 1850 pages. Available in PDF, EPUB and Kindle. Book excerpt: Faculties, publications and doctoral theses in departments or divisions of chemistry, chemical engineering, biochemistry and pharmaceutical and/or medicinal chemistry at universities in the United States and Canada.
Download or read book Growth of A Plane GaN Films on R Plane Sapphire by Combining Metal Organic Vapor Phase Epitaxy with the Hydride Vapor Phase Epitaxy Supported by the National Natural Science Foundation of China Under Grant No 61204006 the Fundamental Research Funds for the Central Universities Under Grant No 7214570101 and the National Key Science and Technology Special Project Under Grant No 2008ZX01002 002 written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
