Download or read book Some Experimental Studies of N Type Gan and Au Gan Contacts written by Ke Wang and published by . This book was released on 2017-01-28 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Some experimental studies of n-type GaN and Au/GaN contacts" by Ke, Wang, 王科, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled SOME EXPERIMENTAL STUDIES OF N-TYPE GaN AND Au/GaN CONTACTS Submitted by Wang Ke for the degree of Master of Philosophy at The University of Hong Kong in December 2002 Schottky and ohmic contacts made on both undoped n-type HVPE (Hydride Vapour Phase Epitaxy) and MBE (Molecular Beam Epitaxy) grown GaN epilayers with similar nominal carrier-concentration levels were studied. Close to ideal Au- GaN Schottky junctions together with low resistance Al and In ohmic contacts were obtained when using the HVPE material. For the MBE material, however, under identical fabrication procedures the electrical characteristics of both Schottky and ohmic contacts were poor. The result was correlated with the material quality of the epilayers observed by photoluminescence spectroscopy, Hall measurement and atomic-force microscopy, which showed that the concentrations of point defects and dislocations were significantly higher in the MBE grown material. It is suggested that point defects or impurity-related defects lead to Schottky contact degradation and the observed increase in ohmic contact resistance. These results show the importance of material quality when making contacts on GaN epilayers and suggest that the intensity of the band-to-band photoluminescence signal is a suitable parameter for assessing the material quality prior to metalization. The electrical characteristics of Au/n-GaN Schottky contacts with different Au film thickness up to 1300A were investigated using current-voltage (I-V) and capacitance-voltage (C-V) techniques. The results showed a steady decrease in the quality of the Schottky diodes for increasing Au-film thickness. The I-V measurements indicated that thin (500 A). Schottky barrier heights obtained by C-V analysis were 0.1-0.2eV greater than those found from the I-V measurements, indicating that current transport through the barrier is not purely thermionic. Ideality factors of 2 confirmed this. Both Schottky barrier height and reverse breakdown bias were found to decrease with increasing Au thickness. Depth profiling Auger Electron Spectroscopy (AES) showed that the Au/GaN junction interface width increased with increasing Au thickness, and suggesting considerable inter-mixing of Au, Ga and N. The results were interpreted in terms of Ga out-diffusion from the GaN giving rise to gallium vacancies that in turn acted as sites for electron-hole pair generation within the depletion region. The study supports the recent suggestion that gallium vacancies associated with threaded dislocations play an important role in junction breakdown. DOI: 10.5353/th_b2666361 Subjects: Gallium nitride Ohmic contacts Diodes, Schottky-barrier
Download or read book Some Experimental Studies of N type GaN and Au GaN Contacts written by Ke Wang (M.Phil.) and published by . This book was released on 2002 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nitride Semiconductors written by Pierre Ruterana and published by John Wiley & Sons. This book was released on 2006-05-12 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor components based on silicon have been used in a wide range of applications for some time now. These elemental semiconductors are now well researched and technologically well developed. In the meantime the focus has switched to a new group of materials: ceramic semiconductors based on nitrides are currently the subject of research due to their optical and electronic characteristics. They open up new industrial possibilities in the field of photosensors, as light sources or as electronic components. This collection of review articles provides a systematic and in-depth overview of the topic, on both a high and current level. It offers information on the physical basics as well as the latest results in a compact yet comprehensive manner. The contributions cover the physical processes involved in manufacture, from semiconductor growth, via their atomic structures and the related characteristics right up to future industrial applications. A highly pertinent book for anyone working in applied materials research or the semiconductor industry.
Download or read book Theoretical and Experimental Approach to Developing Improved Electrical Contacts to GaN written by Suzanne Mohney and published by . This book was released on 1999 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: The metallurgy and electrical performance of contacts to GaN were examined. Thermodynamic estimates coupled with experimental work revealed clear trends in the nature of the contact metallurgy depending upon the position of the metal in the periodic table. This information was then used to aid in the investigation and design of electrical contacts to GaN. Ohmic contacts to n-GaN, Schottky barriers to n-GaN, and ohmic contacts to p-GaN were fabricated and characterized. These studies resulted in an improved understanding of the mechanism of ohmic contact formation in Al/Ti/n-GaN contacts, along with the development of TiN/Ti/n-GaN and ZrN/Zr/n-GaN ohmic contacts with exceptional thermal stability at 600 deg C and contact resistivities of 6 x 10(exp -6) and 2 x 10(exp -5) ohm.sq cm, respectively, for n = 7 x 10(exp 17) cu cm. Also developed were Re/n-GaN Schottky barrier contacts that were stable upon annealing at 700 deg C with current-voltage and capacitance-voltage barrier heights of 0.82 and 1.06 eV, respectively. For ohmic contacts to p-GaN, a large number of contacts were evaluated. A clear improvement over conventional Au/Ni/p-GaN contacts was provided by electrodeposited Pt/p-GaN and sputtered Pt/Ni/p-GaN contacts, which provided contact resistivities that were lower than Au/Ni/p-GaN contacts by more than a factor of two. An explanation for this improvement was formulated.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book GaN and Related Materials written by Stephen J. Pearton and published by CRC Press. This book was released on 1997-10-29 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents views on current developments in heat and mass transfer research related to the modern development of heat exchangers. Devotes special attention to the different modes of heat and mass transfer mechanisms in relation to the new development of heat exchangers design. Dedicates particular attention to the future needs and demands for further development in heat and mass transfer. GaN and related materials are attracting tremendous interest for their applications to high-density optical data storage, blue/green diode lasers and LEDs, high-temperature electronics for high-power microwave applications, electronics for aerospace and automobiles, and stable passivation films for semiconductors. In addition, there is great scientific interest in the nitrides, because they appear to form the first semiconductor system in which extended defects do not severely affect the optical properties of devices. This series provides a forum for the latest research in this rapidly-changing field, offering readers a basic understanding of new developments in recent research. Series volumes feature a balance between original theoretical and experimental research in basic physics, device physics, novel materials and quantum structures, processing, and systems.
Download or read book Gallium Nitride Processing for Electronics Sensors and Spintronics written by Stephen J. Pearton and published by Springer Science & Business Media. This book was released on 2006-02-24 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor spintronics is expected to lead to a new generation of transistors, lasers and integrated magnetic sensors that can be used to create ultra-low power, high speed memory, logic and photonic devices. Useful spintronic devices will need materials with practical magnetic ordering temperatures and current research points to gallium and aluminium nitride magnetic superconductors as having great potential. This book details current research into the properties of III-nitride semiconductors and their usefulness in novel devices such as spin-polarized light emitters, spin field effect transistors, integrated sensors and high temperature electronics. Written by three leading researchers in nitride semiconductors, the book provides an excellent introduction to gallium nitride technology and will be of interest to all reseachers and industrial practitioners wishing to keep up to date with developments that may lead to the next generation of transistors, lasers and integrated magnetic sensors.
Download or read book Graphene Science Handbook Six Volume Set written by Mahmood Aliofkhazraei and published by CRC Press. This book was released on 2016-04-26 with total page 3379 pages. Available in PDF, EPUB and Kindle. Book excerpt: Graphene is the strongest material ever studied and can be an efficient substitute for silicon. This six-volume handbook focuses on fabrication methods, nanostructure and atomic arrangement, electrical and optical properties, mechanical and chemical properties, size-dependent properties, and applications and industrialization. There is no other major reference work of this scope on the topic of graphene, which is one of the most researched materials of the twenty-first century. The set includes contributions from top researchers in the field and a foreword written by two Nobel laureates in physics. Volumes in the set: K20503 Graphene Science Handbook: Mechanical and Chemical Properties (ISBN: 9781466591233) K20505 Graphene Science Handbook: Fabrication Methods (ISBN: 9781466591271) K20507 Graphene Science Handbook: Electrical and Optical Properties (ISBN: 9781466591318) K20508 Graphene Science Handbook: Applications and Industrialization (ISBN: 9781466591332) K20509 Graphene Science Handbook: Size-Dependent Properties (ISBN: 9781466591356) K20510 Graphene Science Handbook: Nanostructure and Atomic Arrangement (ISBN: 9781466591370)
Download or read book Advanced Research on Industry Information System and Material Engineering IISME2012 written by Helen Zhang and published by Trans Tech Publications Ltd. This book was released on 2012-01-24 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt: In these proceedings are to be found original ideas and new insights on many aspects of Industry, information Systems and Materials Engineering. The conference was an excellent platform for researchers to exchange innovative ideas and new perspectives. The 140 papers are grouped into the following: 1: Industrial Technology, Materials Engineering and Dynamic Systems, 2: Industry, Manufacturing Technology and Mechanical Engineering, 3: Materials Science, Machine Systems and Production Systems and 4: Materials Engineering, Energy Science and Ecological Resources. Volume is indexed by Thomson Reuters CPCI-S (WoS).
Download or read book Proceedings of the Third Symposium on III V Nitride Materials and Processes written by T. D. Moustakas and published by The Electrochemical Society. This book was released on 1999 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book State of the Art Program on Compound Semiconductors 46 SOTAPOCS 46 and Processes at the Semiconductor Solution Interface 2 written by C. O'Dwyer and published by The Electrochemical Society. This book was released on 2007 with total page 647 pages. Available in PDF, EPUB and Kindle. Book excerpt: Section 1 addresses the most recent developments in processes at the semiconductor-solution interface include etching, oxidation, passivation, film growth, porous semiconductor formation, electrochemical, photoelectrochemical, electroluminescence and photoluminescence processes, electroanalytical measurements and related topics on both elemental and compound semiconductors. Section 2 addresses the most recent developments in compound semiconductors encompassing advanced devices, materials growth, characterization, processing, device fabrication, reliability, and related topics.
Download or read book III V Nitride Semiconductors written by Edward T. Yu and published by CRC Press. This book was released on 2022-10-30 with total page 718 pages. Available in PDF, EPUB and Kindle. Book excerpt: The concepts in this book will provide a comprehensive overview of the current state for a broad range of nitride semiconductor devices, as well as a detailed introduction to selected materials and processing issues of general relevance for these applications. This compilation is very timely given the level of interest and the current stage of research in nitride semiconductor materials and device applications. This volume consists of chapters written by a number of leading researchers in nitride materials and device technology addressing Ohmic and Schottky contacts, AIGalnN multiple quantum well laser diodes, nitride vertical cavity emitting lasers, and ultraviolet photodetectors. This unique volume provides a comprehensive review and introduction to application and devices based on GaN and related compounds for newcomers to the field and stimulus to further advances for experienced researchers.
Download or read book Compound Semiconductors Strained Layers and Devices written by Suresh Jain and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, extensive work has been done on strain, dislocations and mechanical properties of strained layers. Although it is not possible to describe all this work in a monograph of this size, Compound Semiconductors Strained Layers and Devices provides an overview with sufficient detail to cover all the essential aspects of recent developments in the field. The book concentrates on compound semiconductors with emphasis on wideband gap II-VI and III-Nitride semiconductors. GeSi strained layers are discussed for comparison to clarify the underlying physics. The effects of strain on band structure, transport, and optical properties of both the zinc blende and the wurtzite compound semiconductors are discussed, as are Piezoelectric Effects and Quantum Confined Stark Effects. Magnetic polarons in diluted II-VI magnetic polarons are also covered. Among the applications, blue and green LEDs and LDs and mid-IR LDs are included. A whole chapter is devoted to these devices. Another chapter examines transistors based on conventional III-V, II-VI and III-nitride semiconductors. The subject matter is treated at a level appropriate for students and senior researchers interested in material science, and in designing and modeling semiconductor devices. It will also be useful to engineers and material scientists concerned with the effects of strain on the mechanical properties of crystalline layers of any material.
Download or read book Oxide and Nitride Semiconductors written by Takafumi Yao and published by Springer Science & Business Media. This book was released on 2009-03-20 with total page 525 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a unique book devoted to the important class of both oxide and nitride semiconductors. It covers processing, properties and applications of ZnO and GaN. The aim of this book is to provide the fundamental and technological issues for both ZnO and GaN.
Download or read book Semiconductor Surfaces and Interfaces written by Winfried Mönch and published by Springer Science & Business Media. This book was released on 2001-04-10 with total page 574 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor Surfaces and Interfaces deals with structural and electronic properties of semiconductor surfaces and interfaces. The first part introduces the general aspects of space-charge layers, of clean-surface and adatom-induced surfaces states, and of interface states. It is followed by a presentation of experimental results on clean and adatom-covered surfaces which are explained in terms of simple physical and chemical concepts. Where available, results of more refined calculations are considered. This third edition has been thoroughly revised and updated. In particular it now includes an extensive discussion of the band lineup at semiconductor interfaces. The unifying concept is the continuum of interface-induced gap states.
Download or read book New Research on Semiconductors written by Thomas B. Elliot and published by Nova Publishers. This book was released on 2006 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes within its scope, topics such as: studies of the structural, electrical, optical and acoustical properties of bulk, low-dimensional and amorphous semiconductors; and, interface properties, including the physics and chemistry of heterojunctions, metal-semiconductor and insulator-semiconductor junctions.
Download or read book III Nitride Semiconductors written by M.O. Manasreh and published by Elsevier. This book was released on 2000-12-06 with total page 463 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research advances in III-nitride semiconductor materials and device have led to an exponential increase in activity directed towards electronic and optoelectronic applications. There is also great scientific interest in this class of materials because they appear to form the first semiconductor system in which extended defects do not severely affect the optical properties of devices. The volume consists of chapters written by a number of leading researchers in nitride materials and device technology with the emphasis on the dopants incorporations, impurities identifications, defects engineering, defects characterization, ion implantation, irradiation-induced defects, residual stress, structural defects and phonon confinement. This unique volume provides a comprehensive review and introduction of defects and structural properties of GaN and related compounds for newcomers to the field and stimulus to further advances for experienced researchers. Given the current level of interest and research activity directed towards nitride materials and devices, the publication of the volume is particularly timely. Early pioneering work by Pankove and co-workers in the 1970s yielded a metal-insulator-semiconductor GaN light-emitting diode (LED), but the difficulty of producing p-type GaN precluded much further effort. The current level of activity in nitride semiconductors was inspired largely by the results of Akasaki and co-workers and of Nakamura and co-workers in the late 1980s and early 1990s in the development of p-type doping in GaN and the demonstration of nitride-based LEDs at visible wavelengths. These advances were followed by the successful fabrication and commercialization of nitride blue laser diodes by Nakamura et al at Nichia. The chapters contained in this volume constitutes a mere sampling of the broad range of research on nitride semiconductor materials and defect issues currently being pursued in academic, government, and industrial laboratories worldwide.
