Download or read book Investigation of Relationship Between the Plasma and Material Characteristics of Zinc Oxide ZnO Thin Film by Radio Frequency RF Reactive Magnetron Sputtering written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reactive High Power Impulse Magnetron Sputtering of Zinc Oxide for Thin Film Transistor Applications written by Amber Nicole Reed and published by . This book was released on 2015 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zinc oxide (ZnO) is an emerging thin film transistor (TFT) material for transparent flexible displays and sensor technologies, where low temperature synthesis of highly crystallographically ordered films over large areas is critically needed. This study maps plasma assisted synthesis characteristics, establishes polycrystalline ZnO growth mechanisms and demonstrates for the first time low-temperature and scalable deposition of semiconducting grade ZnO channels for TFT applications using reactive high power impulse magnetron sputtering (HiPIMS). Plasma parameters, including target currents, ion species and their energies were measured at the substrate surface location with mass spectroscopy as a function of pressure and applied voltage during HiPIMS of Zn and ZnO targets in O2/Ar. The results were correlated to film microstructure development investigated with x-ray diffraction, atomic force microscopy, scanning electron microscopy and transmission electron microscopy which helped establish film nucleation and growth mechanisms. Competition for nucleation by (100), (101) and (002) oriented crystallites was identified at the early stages of film growth, which can result in a layer of mixed crystal orientation at the substrate interface, a microstructural feature that is detrimental to TFT performance due to increased charge carrier scattering in back-gated TFT devices. The study revealed that nucleation of both (100) and (101) orientations can be suppressed by increasing the plasma density while decreasing ion energy. After the initial nucleation layer, the microstructure evolves to strongly textured with the (002) crystal plane oriented parallel to the substrate surface. The degree of (002) alignment was pressure-dependent with lower deposition pressures resulting in films with (002) alignment less than 3.3°, a trend attributed to less energy attenuation of the low energy (2- 6 eV) Ar+, O+, and O2+ ions observed with mass spectrometry measurements. At pressures of 7 mTorr and lower, a second population of ionized gas (Ar+, O+, and O2+) species with energies up to 50 eV appeared. The presence of higher energy ions corresponded with a bimodal distribution of ZnO grain sizes, confirming that high energy bombardment has significant implications on microstructural uniformity during large area growth. Based on the established correlations between process parameters, plasma characteristics, film structure and growth mechanisms, optimum deposition conditions for (002) oriented nanocrystalline ZnO synthesis at 150 °C were identified and demonstrated for both silicon oxide wafers of up to 4 inch diameter and on flexible polymer (Kapton) substrates. The feasibility of the low temperature processing of ZnO films for TFT applications was verified by preliminary tests with back-gated device prototypes. Directions of future research are outlined to further develop this low temperature growth method and apply results of this study for ZnO applications in semiconductor devices.

Download or read book Optical Properties of Zinc Oxide ZnO Thin Film by RF Magnetron Sputtering written by Khairul Nadzrin Rosli and published by . This book was released on 2006 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ceramic Abstracts written by American Ceramic Society and published by . This book was released on 1995 with total page 1150 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Structural and Electrical Properties of Radio Frequency Sputtered Fluorine Doped Zinc Oxide Films written by Adam S. Bowen and published by . This book was released on 2009 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: Deposits, by radio frequency magnetron sputtering disposition, thin films of fluorine doped zinc oxide onto polyethylene naphthalate and glass substrates at room temperature. Studies of the effects of post disposition annealing by argon and a gas mixture of argon and hydrogen on the structural and electrical properties of the films deposited on polyethylene naphthalate and glass.

Download or read book Micro Electronic and Mechanical Systems written by Kenichi Takahata and published by BoD – Books on Demand. This book was released on 2009-12-01 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses key aspects of MEMS technology areas, organized in twenty-seven chapters that present the latest research developments in micro electronic and mechanical systems. The book addresses a wide range of fundamental and practical issues related to MEMS, advanced metal-oxide-semiconductor (MOS) and complementary MOS (CMOS) devices, SoC technology, integrated circuit testing and verification, and other important topics in the field. ?Several chapters cover state-of-the-art microfabrication techniques and materials as enabling technologies for the microsystems. Reliability issues concerning both electronic and mechanical aspects of these devices and systems are also addressed in various chapters.

Download or read book Nanomaterials Based Composites for Energy Applications written by Keka Talukdar and published by CRC Press. This book was released on 2019-12-11 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume, Nanomaterials-Based Composites for Energy Applications: Emerging Technology and Trends, covers the importance of nanomaterials-based composites for renewable and alternative energy applications. Taking a multidisciplinary approach, it looks at using composites without losing the extraordinary strength of the nanomaterials, preparing new composites with high dielectric permittivity, improving load-carrying capacity, and more. Simulation and experimental work is included, providing a current view of the research that is going on in laboratories all over the world. The book will be a rich reference for professors and instructors, professionals, researchers, and engineering students interested in applying the emerging field of nanoscience and nanotechnology to energy applications.

Download or read book The Optical and Mechancial Properties of ZnO F Thin Films Deposited Onto Polyethylene Napthalate and Glass written by Stanley R. Potoczny and published by . This book was released on 2008 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: Investigates fluorine doped zinc oxide (F doped ZnO) films deposited on both glass and polyethylene napthalate (PEN) substrates by radio frequency (RF) magnetron sputtering and the effect of post growth annealing in different ambients. Analyzes the optical and mechanical properties of these films using atomic force microscopy, transmission and reflectance measurements, and mechanical bend testing.

Download or read book Materials Engineering and Automatic Control written by Liu Feng and published by Trans Tech Publications Ltd. This book was released on 2012-08-30 with total page 3000 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings of the 2012 International Conference on Materials Engineering and Automatic Control (ICMEAC 2012), held on August 27-28th 2012 in Jinan, China, comprise 486 peer-reviewed papers: grouped into the chapters: Organization, Defects and Performance of Materials; Testing and Analysis Techniques of Materials; Metallic Materials; Inorganic Non-Metallic Materials; Composite Materials; Materials Synthesis and Processing Technology; Mechanics; Mechanical Design; Mechanical Manufacturing Processes and Equipment; Mechanical Power Transmission and Control; Mechanical Dynamics and Vibration; Measuring and Testing Instruments; Control System Simulation Technology; Mechatronics Technology; Automation Technology; Auto-Detection Technology; Automatic Control Technology.

Download or read book Nanocoatings Nanosystems Nanotechnologies written by Alexander D. Pogrebnjak and published by Bentham Science Publishers. This book was released on 2012-09-17 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Reference eBook deals with an existing classification of a nanosized structure and an analysis of its properties. It summarizes an information about how a grain size affects physical, mechanical, thermal, and other properties of a nanostructured material. A basic method, which is employed for a fabrication of an isolated nanoparticle, an ultradisperse powder, a compact nanocystalline, nanoporous, and amorphous material, a fullerene, a nanotube, and a nanostuctured coating, is considered. Investigation methods, which are applied to study the nanostructured material, are briefly described. A modern understanding of a formation of the nanostructured and nanocomposite coating, which are fabricated using a ion-plasma deposition method, is reposted. A potential application of the nanostructured material and coating in a field of engineering is demonstrated. Readership: Graduate, Postgraduate, Ph.D. Students, Researchers and Industry Professionals. The eBook contains 9 Chapters, 87 Figures, 14 Tables, 411 References-totally, 155 Pages. It was approved by two Scientific Boards from National Kharkov University and Sumy State University. A main content of this eBook is a basis for lectures presented for students at Sumy State University (the Physical-Technical Faculty), Kharkov National University (the Physical Faculty), Omsk State University (the Physical Faculty, the Department of Material Science), East-Kazakhstan State Technical University (Ust-Kamenogorsk, Kazakhstan), and Moscow State University (the Physical Faculty, Moscow, Russia). A source of this eBook is original papers of leading world-known scientists, who ware involved in a field of new nano composite material fabrication, nanotechnologies, and researches. This version had not been published elsewhere. It is interesting for a wide circle of specialists, Masters, aspirants, scientific researchers, and a technical staff of Higher Education System, Research Institutes and Laboratories. It covers recent data since 2008 to 2010 year.

Download or read book ZnO Thin Films written by Paolo Mele and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zinc oxide (ZnO) is an n-type semiconductor with versatile applications such as optical devices in ultraviolet region, piezoelectric transducers, transparent electrode for solar cells and gas sensors. This book "ZnO Thin Films: Properties, Performance and Applications" gives a deep insight in the intriguing science of zinc oxide thin films. It is devoted to cover the most recent advances and reviews the state of the art of ZnO thin films applications involving energy harvesting, microelectronics, magnetic devices, photocatalysis, photovoltaics, optics, thermoelectricity, piezoelectricity, electrochemistry, temperature sensing. It serves as a fundamental information source on the techniques and methodologies involved in zinc oxide thin films growth, characterization, post-deposition plasma treatments and device processing. This book will be invaluable to the experts to consolidate their knowledge and provide insight and inspiration to beginners wishing to learn about zinc oxide thin films.

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 Reactive Sputtering Deposition and Characterization of Zinc Nitride and Oxy nitride Films for Electronic and Photovoltaic Applications written by Nanke Jiang and published by . This book was released on 2013 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation presents a study on the fabrication of zinc nitride and zinc oxy-nitride films, and related hetero-structures on glass, silicon and other substrates. The goals of this study include gaining fundamental understanding on the electrical and optical properties, the chemical-bonding states and the micro-structure of these materials and examining their potential for photovoltaic and other electronic and optoelectronic applications. Reactive radio-frequency (RF) magnetron sputtering was used as the deposition method, which potentially enables control of composition of the thin films, as well as fabrication of multilayer structures for the study of possible hetero-junctions between zinc nitride and zinc oxy-nitrides. Along with reactive sputtering, several other fabrication methods, such as thermal evaporation and solution (e.g. silver or carbon paste) painting, were used as auxiliaries where necessary. The characterization techniques employed include (i) x-ray based techniques (x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), energy dispersive x-ray spectroscopy (EDXS)), (ii) optical based methods (spectroscopic ellipsometry (SE), optical spectrophotometry, Raman spectroscopy), (iii) scanning electron microscopy (SEM), and (iv) electrical measurements (resistivity, Hall effect measurements, current-voltage and photovoltaic measurements). The cross-correlation between the deposition/post-deposition conditions and the physical properties of the films was investigated. The deposition conditions, such as the nitrogen (or oxygen) partial concentration in the sputtering gas mixture, substrate temperatures, total deposition pressure, as well as the post-deposition treatments such as thermal treatment and/or oxidation in ambient, were studied in detail. Zinc nitride, with a small fraction of "naturally" incorporated oxygen, is found to be a promising candidate for photovoltaic applications because of its optical and electrical properties. Also, the capability of property tuning for the zinc oxy-nitride material system was demonstrated by intentionally introducing varied amount oxygen into zinc nitride. In order to better understand the crystalline structure and the electronic band structure of these materials, first principle density functional theory (DFT) was used for computations of pure zinc nitride and the doping effects in it with both native elements (Zn, N) and copper family elements (Cu, Ag, Au) as possible p-type dopants. Atomic geometry, formation energy, as well as electronic structure of defects in zinc nitride were studied and a general consistency was observed between theoretically calculated and experimentally determined results. Defect density of states (DOS) suggest that among all three studied copper-family elements, copper is a good candidate for a p-type dopant. Technological insight and approaches to the fabrication of device-relevant structures were the other important outcomes of this work. Our studies showed that the fabrication of device-relevant ohmic contacts, rectifying metal-nitride junctions and p-n junctions was possible. Substantial photovoltaic action was observed in a single junction solar cell configuration that uses p-type zinc oxy-nitride as an absorber layer.

Download or read book Nanosensors for Smart Cities written by Baoguo Han and published by Elsevier. This book was released on 2020-02-13 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanosensors for Smart Cities covers the fundamental design concepts and emerging applications of nanosensors for the creation of smart city infrastructures. Examples of major applications include logistics management, where nanosensors could be used in active transport tracking devices for smart tracking and tracing, and in agri-food productions, where nanosensors are used in nanochips for identity, and food inspection, and smart storage. This book is essential reading for researchers working in the field of advanced sensors technology, smart city technology and nanotechnology, and stakeholders involved in city management. Nanomaterials based sensors (nanosensors) can offer many advantages over their microcounterparts, including lower power consumption, high sensitivity, lower concentration of analytes, and smaller interaction distance between object and sensor. With the support of artificial intelligence (AI) tools, such as fuzzy logic, genetic algorithms, neural networks, and ambient-intelligence, sensor systems are becoming smarter. - Provides information on the fabrication and fundamental design concepts of nanosensors for intelligent systems - Explores how nanosensors are being used to better monitor and maintain infrastructure services, including street lighting, traffic management and pollution control - Assesses the challenges for creating nanomaterials-enhanced sensors for mass-market consumer products

Download or read book Nanorods written by Dr. Orhan Yalçın and published by BoD – Books on Demand. This book was released on 2012-03-09 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book "Nanorods" is an overview of the fundamentals and applications of nanosciences and nanotechnologies. The methods described in this book are very powerful and have practical applications in the subjects of nanorods. The potential applications of nanorods are very attractive for bio-sensor, magneto-electronic, plasmonic state, nano-transistor, data storage media, etc. This book is of interest to both fundamental research such as the one conducted in Physics, Chemistry, Biology, Material Science, Medicine etc., and also to practicing scientists, students, researchers in applied material sciences and engineers.

Download or read book Process Variations in Microsystems Manufacturing written by Michael Huff and published by Springer Nature. This book was released on 2020-04-09 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book thoroughly examines and explains the basic processing steps used in MEMS fabrication (both integrated circuit and specialized micro machining processing steps. The book places an emphasis on the process variations in the device dimensions resulting from these commonly used processing steps. This will be followed by coverage of commonly used metrology methods, process integration and variations in material properties, device parameter variations, quality assurance and control methods, and design methods for handling process variations. A detailed analysis of future methods for improved microsystems manufacturing is also included. This book is a valuable resource for practitioners, researchers and engineers working in the field as well as students at either the undergraduate or graduate level.

Download or read book Electrical Characterization of ZnO thin films grown by molecular beam epitaxy written by Vladimir Petukhov and published by Cuvillier Verlag. This book was released on 2012-04-25 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the electronic and optoelectronic device realization a precise control of the electrical properties in the utilized material is a very important issue. Doping profiles in realized p-njunctions influence the functionality of the devices. The morphological and crystal properties of a device material directly influence the electrical ones. Dislocations present in a region of p-n-junctions can short circuit them leading to malfunctions. Too rough surfaces during epitaxial growth could lead to inhomogeneities in a single or multiple quantum wells and superlattices. The main goal of the present work was to provide the basis for a reliable p-type doping of ZnO grown by molecular beam epitaxy. Firstly, the well established heteroepitaxial growth on c-sapphire substrates has been employed. Based on the theoretical and experimental works, suggesting nitrogen to be the impurity that builds the most shallow acceptor level in ZnO comparing to other group-V elements, it has been implied as a dopant. To generate reactive nitrogen atoms an rf-plasma source has been utilized in the MBE process. The resulting samples have been characterized by such methods as AFM, XRD, TEM, PL spectroscopy, temperature domain Hall measurements (TDHM) and ECV-profiling. First results of TDHM have shown that even in undoped samples the temperature dependencies of the electron mobility and carrier concentration have regions which are difficult to interpret. It is necessary to fit them with theoretical curves in order to extract the correct values. This task has proven to be very difficult. The complicated character of the dependencies has been explained in terms of the multilayer conduction model dividing a layer in thin interfacial region with mobility and carrier concentration μ1 and n1 respectivly and bulk region with a higher mobility μ2 and lower carrier concentration n2. The electrical transport in the bulk region has been modeled in terms of the general scattering theory in polar semiconductors. Such scattering mechanisms as scattering on polar-optical phonons, piezoelectric phonons, acoustic deformation potential, strain induced fields, dislocations, ionized and neutral impurities have been taken into account. Two cases have been considered to model transport in the interfacial region: 1) transport takes place in the conduction band of a highly doped degenerate semiconductor; 2) transport takes place in the impurity band formed by intermediate concentration of impurities and in conduction band in parallel. In the second case transport at the interface in conduction band has been neglected in the region of the low temperatures due to the impurities freeze-out and carrier concentration has been taken temperature independent like in the first case. To investigate experimentally the transport character in these two regions independently a mobility-spectrum analysis has been conducted. Theoretical results utilizing the two models have been compared with experimentally extracted mobility and carrier concentration in the interfacial region. It has been concluded that the concentration of donors in the layers is not high enough for the impurity band to merge with the conduction band and the second model is more consistent. The theoretically acquired donor concentration profiles have been compared with ECV-profiles. The agreement is very good. Simulations have revealed a shallow donor state with the ionization energy of approximately 45 meV . In the literature, this donor state in ZnO is attributed to hydrogen. However, due to the high diffusion mobility of hydrogen in ZnO, an annealing process would obviously decrease the carrier concentration in the samples which has not been the case. It has been suggested that the main donor centers are the electrically active crystal point defects generated by dislocations. Layers doped with nitrogen have been grown at very low temperatures (≈ 200°C) and at temperatures ranging from 400°C to 500°C, which are optimal for the epitaxial growth of ZnO. The samples grown at low temperatures are single crystalline with mosaic structure. In both cases, the introduction of the dopant increased the carrier concentration. This has been accounted for a bad crystal quality resulting in the inhomogeneous incorporation of nitrogen and for high background donor concentration due to the high dislocations densities. Additionally, the incorporation of acceptor centers shifts the Fermi-level increasing the formation probability of the compensating point defects. The analysis of TDHM showed an inconsistency of the one donor level model in the case of nitrogen doped samples. This fact and the decrease in the carrier concentration after annealing at 800°C for 30 minutes in ambient air can be explained by nitrogen forming donor-like defect complexes. In an attempt to improve the crystal quality of the heteroepitaxial layers, 15 periods of a ZnO/Zn0.6Mg0.4O superlattice structure have been inserted between the conventional double HT-MgO/LT-ZnO buffer and a main HT-ZnO layer. TDHM has revealed a very high mobility close to the values measured in a bulk ZnO for the temperature range of 20 - 300 K. However, TEM investigations of the samples have not indicated any decrease in the dislocation density comparing with the similar samples without a superlattice. Such a high mobility has been attributed to an electron transport in the superlattice structure. Heteroepitaxial growth of high quality ZnO-layers has proven to be challenging leaving the homoepitaxial growth as the only possibility to obtain the epitaxial layers with the best structural and electrical properties. The hydrothermally grown bulk ZnO substrates from two supplying companies, CrysTec and TokyoDenpa, have been employed for homoepitaxy. The substrates from CrysTec have not been epi-ready. Although AFM images reveal very flat surface, this has been damaged by the process of the chemomechanical polishing. This damaged layer must be removed. This has been achieved by the thermal annealing for 3 hours at 1050°C in ambient air. The thermally treated surfaces resulted in atomically flat terraces. XRD measurements have indicated an improvement of the crystal quality after annealing. The resistivity of the bulk substrates decreased after the thermal treatment due to out-diffusion of the compensating Li atoms letting Al, Ga and In atoms to contribute to conduction. After the longer annealing processes the etch-pits have been discovered on O-polar faces. The same features could be achieved by the chemical etching in a nitric acid on Zn-polar faces. The density of the threading dislocations on both polar faces for both types of substrates calculated by the etch-pit density investigation is about 105 1/cm2. Further the thermally treated substrates with atomically flat terraces have been utilized for homoepitaxy. The differences in growth kinetics during the molecular beam epitaxy on such substrates with the improved surface quality depending on their polarity have been investigated by RHEED measurements. The growth on a Zn-polar face has a 3D-character independently on a supplier. Morphologies of the resulting O- and Zn-polar layers have shown to be different. This has been explained by the presence of dangling bonds on Opolar face and thus, shorter diffusion time of the impinging Zn atoms on the surface. XRD and TEM measurements have shown a perfect crystal quality of the overgrown layers. The PL spectra of homoepitaxial layers are governed by the donor impurities diffused from the substrates. Considering the SIMS measurements of homoepitaxial layers found in the literature it has been concluded that the diffusion of donors in the layers grown on Zn-polar faces takes less effect then for the O-polar films. This conclusion has enforced the utilization of Zn-polar substrates supplied by CrysTec for the experiments with nitrogen doping of ZnO because of their affordable price. The electrical properties measured by ECV-profiling in series of homoepitaxial layers with varied growth parameters have shown an increase of the carrier concentration with the nitrogen incorporation. In addition, it has also been shown that the resulting electrical properties near the interface are governed mostly by the initial properties of the substrates. With increasing thickness of the layers carrier concentration saturated to the values of around 1016 1/cm3. The recent successful realization of the p-type MgZnO layers on TokyoDenpa substrates by researchers from Japan suggests switching to the p-type doped alloys because the above discussed results indicate that p-type doping with nitrogen of a pure ZnO is very difficult or even impossible. This is due to a rather fundamental reason: the formation of the compensating donor centers with the incorporation of acceptor atoms. As the first step in the future works, it is obvious to try to reproduce the results of the ZnMgO p-type doping with nitrogen employing growth on ZnO substrates.