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Fabrication Of Field Emitter Arrays Of Carbon Nanotubes Aligned On Patterned Substrates Using Self Assembly Monolayers
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Book Synopsis Fabrication of Field Emitter Arrays of Carbon Nanotubes Aligned on Patterned Substrates Using Self-assembly Monolayers by : Ok-Joo Lee
Download or read book Fabrication of Field Emitter Arrays of Carbon Nanotubes Aligned on Patterned Substrates Using Self-assembly Monolayers written by Ok-Joo Lee and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Aligned Carbon Nanotubes by : Zhifeng Ren
Download or read book Aligned Carbon Nanotubes written by Zhifeng Ren and published by Springer Science & Business Media. This book was released on 2012-09-05 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a survey of the physics and fabrication of carbon nanotubes and their applications in optics, electronics, chemistry and biotechnology. It focuses on the structural characterization of various carbon nanotubes, fabrication of vertically or parallel aligned carbon nanotubes on substrates or in composites, physical properties for their alignment, and applications of aligned carbon nanotubes in field emission, optical antennas, light transmission, solar cells, chemical devices, bio-devices, and many others. Major fabrication methods are illustrated in detail, particularly the most widely used PECVD growth technique on which various device integration schemes are based, followed by applications such as electrical interconnects, nanodiodes, optical antennas, and nanocoax solar cells, whereas current limitations and challenges are also be discussed to lay the foundation for future developments.
Book Synopsis Fabrication and Self-Assembly of Nanobiomaterials by : Alexandru Grumezescu
Download or read book Fabrication and Self-Assembly of Nanobiomaterials written by Alexandru Grumezescu and published by William Andrew. This book was released on 2016-01-06 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fabrication and Self-Assembly of Nanobiomaterials presents the most recent findings regarding the fabrication and self-assembly of nanomaterials for different biomedical applications. Respected authors from around the world offer a comprehensive look at how nanobiomaterials are made, enabling knowledge from current research to be used in an applied setting. Recent applications of nanotechnology in the biomedical field have developed in response to an increased demand for innovative approaches to diagnosis, exploratory procedures and therapy. The book provides the reader with a strong grounding in emerging biomedical nanofabrication technologies, covering numerous fabrication routes for specific applications are described in detail and discussing synthesis, characterization and current or potential future use. This book will be of interest to professors, postdoctoral researchers and students engaged in the fields of materials science, biotechnology and applied chemistry. It will also be highly valuable to those working in industry, including pharmaceutics and biotechnology companies, medical researchers, biomedical engineers and advanced clinicians. An up-to-date and highly structured reference source for practitioners, researchers and students working in biomedical, biotechnological and engineering fields A valuable guide to recent scientific progress, covering major and emerging applications of nanomaterials in the biomedical field Proposes novel opportunities and ideas for developing or improving technologies in fabrication and self-assembly
Book Synopsis Nanotube-based Devices by : Patrick Bernier
Download or read book Nanotube-based Devices written by Patrick Bernier and published by . This book was released on 2003 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Touting the "strong potential of nanotubes for industrial applications" such as electrical leads, rectifiers, transistors, actuators, and cold electron sources, a team of materials scientists from France, South Korea, Germany, and the U.S. present the 33 papers from the April 2003 meeting. The papers have been organized according to the themes of nanotube devices, synthesis, structural and electrical characterization, functionalization and engineering, and composite devices. Annotation : 2004 Book News, Inc., Portland, OR (booknews.com).
Book Synopsis Carbon Nanotube Arrays - by : Sean Michael Foradori
Download or read book Carbon Nanotube Arrays - written by Sean Michael Foradori and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconducting, single walled carbon nanotubes (CNTs) are exceptional electronic materials with high current carrying capacity, a tunable band gap, and nanoscale dimensions. Single CNTs in research devices have demonstrated these excellent material properties. Extrapolation of these single CNT results to devices with many CNTs in tightly packed and highly aligned arrays indicates that CNTs can exceed the performance of existing silicon based devices in many applications by operating at lower voltages and using less energy. The performance of array based devices has not yet met these high expectations, however, due in part to practical challenges in fabricating arrays and integrating those arrays into devices. Aligned arrays can be deposited using many different processes to generate a wide range of CNT packing densities and array morphologies. The morphology and packing density both can affect device performance. Polymer wrapped CNTs with high semiconductor purity are often used in these arrays, but the polymer wrapper must be removed from the CNT array to achieve the best device performance. Chapter 2 examines the impact of CNT bundles on the performance of field effect transistors (FETs) with relatively weak gates. These bundles, colinear aggregates containing multiple CNTs, are formed during some array fabrication processes and can behave differently from individual CNTs. When using relatively weak gates, bundles have a current density similar to individual CNTs, but they have different threshold voltages than individual CNTs, meaning their conductivity turns on and off at different gate voltages. Arrays with a mixture of individual and bundled CNTs make devices with poor subthreshold swing because the gate cannot turn the whole array off at any particular voltage; the array turns off gradually as the gate voltage changes. Chapter 3 examines bundles in FETs with strong ion gel gates. A strong gate can turn on multiple CNTs in a bundle, increasing their current density relative to individual CNTs. An FET with a strong gate and a CNT array containing many bundles will have a higher transconductance than a device with an array containing only individual CNTs. This can be useful in radio frequency transistors because their high frequency performance improves as transconductance increases, but is degraded by parasitic capacitance effects if the channel width is increased. By using an array of bundled CNTs instead of an array of individual CNTs, the transconductance can be increased without increasing the channel width. Chapter 4 describes a strategy to fabricate monolayer arrays with high packing density and very little bundling. Passing a substrate through a macroscopic liquid-liquid interface can deposit aligned arrays of CNTs at the liquid-liquid-substrate contact line. The new strategy uses lithographically defined, microscopic water droplets on substrates to form a contact line that is more stable and improves the array deposition. The advantage of patterned microscopic droplets is that the contact line is pinned by the hydrophilic/hydrophobic border of the chemical pattern, and is decoupled from the motions of the substrate and macroscopic liquid-liquid interface. This relatively stable contact line moves as each CNT is deposited, allowing subsequent CNTs to deposit adjacent to the previously deposited ones, improving the alignment and increasing the packing density to 250 CNTs ℗æm-1 with very little bundling. Devices made using these arrays have exceptionally high current density and transconductance of 1.9 mA ℗æm-1 and 1.2 mS ℗æm-1 at a channel length of 60 nm using just a 0.6 V drain voltage. This is a >2x performance improvement over arrays formed with similar conditions but deposited at the contact line of the macroscopic interface. Finally, Chapter 5 investigates a yttrium (Y) based post-deposition process used to mitigate the effects of wrapping polymer in CNT FETs. Though this process has been used for several years, very little information has been reported about how it works. We use physical and spectroscopic measurements to examine the mechanism, selectivity, extent of etching, and range of conditions available for removing the wrapping polymer PFO-BPy from CNTs. The Y-treatment process consists of depositing 3 nm of metallic Y on the sample, annealing in air at a fixed temperature and time, then etching the sample in dilute HCl for 5 seconds, and rinsing in DI water. Annealing at 90°C or cooler for 30 minutes will oxidize ~0.5 nm of a PFO-BPy film, forming highly oxidized carbonate, carboxylate and/or carbonyl groups, allowing it to dissolve in dilute aqueous acid. Repeated Y-treatment cycles will etch more material, and thicker layers of up to 2.5 nm can be etched by annealing at 250°C for 120 minutes. Reactions with sp2 based CNTs and graphene only occur at elevated temperatures, allowing selective removal of wrapping polymer from CNTs at lower temperatures. Furthermore, the yttrium process can remove all parts of the PFO-BPy polymer molecule, in contrast to high-temperature vacuum annealing which only removes alkyl side groups and leaves much of the polymer chain intact.
Book Synopsis Fabrication, Field Emission Properties and Theoretical Simulation of Triode-type Carbon Nanotube Emitter Arrays by : Jianfeng Wu
Download or read book Fabrication, Field Emission Properties and Theoretical Simulation of Triode-type Carbon Nanotube Emitter Arrays written by Jianfeng Wu and published by . This book was released on 2010 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes exhibit excellent field emission properties and will likely be prime candidates as electron sources in future vacuum electronic applications. Recent research has focused on enhancing field emission from traditional diode-type emitters by adding a gate electrode between the anode and the cathode. Since the gate to cathode (emitter) distance in this triode-type structure is small relative to the anode to cathode distance, this structure allows relatively small gate voltages to significantly enhance or dampen field emission. The key challenge for this research is: synthesizing vertically aligned carbon nanotube field emitters inside arrays of triode-type devices. The most common "top-down", etch-deposit-synthesis method of synthesizing carbon nanotubes inside gated cavities is discussed here, and a novel "bottom-up" method is presented. This new approach bypasses the lithography and wet chemistry essential to the etch-deposit-synthesis method, instead using a dual-beam focused ion beam (FIB) system to mill cavities into a multi-layered substrate. Here the substrate is designed such that the act of milling a hole simultaneously creates the gate structure and exposes the catalyst from which carbon nanotubes can then be grown. Carbon nanotubes are synthesized using plasma enhanced chemical vapor deposition (PECVD) rather than thermal chemical vapor deposition, due to the superior alignment of the PECVD growth. As dual-beam FIB and PECVD can both be largely computerized, this synthesis method is highly reproducible. The dual-beam FIB also permits a high degree of controllability in gate radius, cavity depth and emitter spacing. The effects of a host of PECVD growth parameters (initial catalyst thickness, gas concentration, growth temperature, temperature ramping rate, chamber pressure, and plasma voltage) were characterized so that the morphology of the carbon nanotube emitters could be controlled as well. This "bottom-up" method is employed to construct functional, large area carbon nanotube field emitter arrays (CNT FEAs). The role of the gate layer in field emission is examined experimentally as well as through theoretical models. Field emission testing revealed that increasing gate voltage by as little as 0.3 V had significant impact on the local electric fields, lowering the turn-on and threshold fields by 3.6 and 3.0 V/um, respectively, and increasing the field enhancement factor from 149 to 222. A quantum mechanical model of such triode-type field emission indicates that the local electric field generated by a negatively or positively biased gate directly impacts the tunneling barrier thickness and thus the achievable emission current. However, the geometry of triode-type devices (gate height, gate radius, emitter density) can influence the degree to which the gate voltage influences field emission. I demonstrate here an effective method of analytically calculating the effect of various such geometric parameters on the field emission. Results show that gate type (the height of the gate relative the emitter tip) can significantly impact the local electric field and hence the type of applications a device is suitable for. Side gates (gate height emitter height) induced the highest local electric field, while top gates (gate height emitter height) provided the greatest controllability. For all gate types, increasing the size of the gate opening increased the local electric field by diminishing the gate-emitter screening effect. However, gate voltages were able to enhance or inhibit the local electric field much more readily with smaller gate radii. Due to the strength of gate-emitter field screening in the triode-type structure, the spacing between emitters had virtually no impact on the local electric field, allowing relatively high emitter densities. These theoretical results, combined with a highly controllable synthesis method, provide valuable information and methodology for those designing and optimizing triode-type devices targeted at specific applications.
Book Synopsis Materials Nanoarchitectonics by : Katsuhiko Ariga
Download or read book Materials Nanoarchitectonics written by Katsuhiko Ariga and published by Elsevier. This book was released on 2023-12-15 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials Nanoarchitectonics: From Integrated Molecular Systems to Advanced Devices provides the latest information on the design and molecular manipulation of self-organized hierarchically structured systems using tailor-made nanoscale materials as structural and functional units. The book is organized into three main sections that focus on molecular design of building blocks and hybrid materials, formation of nanostructures, and applications and devices. Bringing together emerging materials, synthetic aspects, nanostructure strategies, and applications, the book aims to support further progress, by offering different perspectives and a strong interdisciplinary approach to this rapidly growing area of innovation. This is an extremely valuable resource for researchers, advanced students, and scientists in industry, with an interest in nanoarchitectonics, nanostructures, and nanomaterials, or across the areas of nanotechnology, chemistry, surface science, polymer science, electrical engineering, physics, chemical engineering, and materials science. Offers a nanoarchitectonic perspective on emerging fields, such as metal-organic frameworks, porous polymer materials, or biomimetic nanostructures Discusses different approaches to utilizing "soft chemistry" as a source for hierarchically organized materials Offers an interdisciplinary approach to the design and construction of integrated chemical nano systems Discusses novel approaches towards the creation of complex multiscale architectures
Book Synopsis Aligned Carbon Nanotubes Vacuum Field Emission Devices by : Yong Mui Wong
Download or read book Aligned Carbon Nanotubes Vacuum Field Emission Devices written by Yong Mui Wong and published by . This book was released on 2006 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: A consistent and reproducible CNTs synthesis method comprising plasma pretreatment of the catalysts prior to CNT synthesis was developed to tailor the surface profile of vertically aligned CNTs. The study found that the plasma pretreatment time and the array spacing of the micropatterned CNT emitters play an important role in achieving the desired field emission characteristics of low turn-on field, high current density and emission stability.
Book Synopsis Controlled Fabrication of Aligned Carbon Nanotube Architectures for Microelectronics Packaging Applications by : Lingbo Zhu
Download or read book Controlled Fabrication of Aligned Carbon Nanotube Architectures for Microelectronics Packaging Applications written by Lingbo Zhu and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is devoted to the fabrication of carbon nanotube structures for microelectronics packaging applications with an emphasis on fundamental studies of nanotube growth and assembly, wetting of nanotube structures, and nanotube-based composites. A CVD process is developed that allows controlled growth of a variety of CNT structures, such as CNT films, bundles, and stacks. Use of an Al2O3 support enhances the Fe catalyst activity by increasing the CNT growth rate by nearly two orders of magnitude under the same growth conditions. By introducing a trace amount of weak oxidants into the CVD chamber during CNT growth, aligned CNT ends can be opened and/or functionalized, depending on the selection of oxidants. By varying the growth temperature, CNT growth can be performed in a gas diffusion- or kinetics-controlled regime. To overcome the challenges that impede implementation of CNTs in circuitry, a CNT transfer process was proposed to assemble aligned CNT structures (films, stacks & bundles) at low temperature which ensures compatibility with current microelectronics fabrication sequences and technology. Field emission and electrical testing of the as-assembled CNT devices indicate good electrical contact between CNTs and solder and a very low contact resistance across CNT/solder interfaces. For attachment of CNTs and other applications (e.g. composites), wetting of nanotube structures was studied. Two model surfaces with two-tier scale roughness were fabricated by controlled growth of CNT arrays followed by coating with fluorocarbon layers formed by plasma polymerization to study roughness geometric effects on superhydrophobicity. Due to the hydrophobicity of nanotube structures, electrowetting was investigated to reduce the hydrophobicity of aligned CNTs by controllably reducing the interfacial tension between carbon nanotubes (CNTs) and liquids. Electrowetting can greatly reduce the contact angle of liquids on the surfaces of aligned CNT films. However, contact angle saturation still occurs.
Book Synopsis Self-assembled Ordered Carbon-nanotube Arrays and Membranes by : Michael P. Siegal
Download or read book Self-assembled Ordered Carbon-nanotube Arrays and Membranes written by Michael P. Siegal and published by . This book was released on 2004 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: Imagine free-standing flexible membranes with highly-aligned arrays of carbon nanotubes (CNTs) running through their thickness. Perhaps with both ends of the CNTs open for highly controlled nanofiltration? Or CNTs at heights uniformly above a polymer membrane for a flexible array of nanoelectrodes or field-emitters? How about CNT films with incredible amounts of accessible surface area for analyte adsorption? These self-assembled crystalline nanotubes consist of multiple layers of graphene sheets rolled into concentric cylinders. Tube diameters (3-300 nm), inner-bore diameters (2-15 nm), and lengths (nanometers - microns) are controlled to tailor physical, mechanical, and chemical properties. We proposed to explore growth and characterize nanotube arrays to help determine their exciting functionality for Sandia applications. Thermal chemical vapor deposition growth in a furnace nucleates from a metal catalyst. Ordered arrays grow using templates from self-assembled hexagonal arrays of nanopores in anodized-aluminum oxide. Polymeric-binders can mechanically hold the CNTs in place for polishing, lift-off, and membrane formation. The stiffness, electrical and thermal conductivities of CNTs make them ideally suited for a wide-variety of possible applications. Large-area, highly-accessible gas-adsorbing carbon surfaces, superb cold-cathode field-emission, and unique nanoscale geometries can lead to advanced microsensors using analyte adsorption, arrays of functionalized nanoelectrodes for enhanced electrochemical detection of biological/explosive compounds, or mass-ionizers for gas-phase detection. Materials studies involving membrane formation may lead to exciting breakthroughs in nanofiltration/nanochromatography for the separation of chemical and biological agents. With controlled nanofilter sizes, ultrafiltration will be viable to separate and preconcentrate viruses and many strains of bacteria for 'down-stream' analysis.
Book Synopsis Journal of Nanoscience and Nanotechnology by :
Download or read book Journal of Nanoscience and Nanotechnology written by and published by . This book was released on 2006 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Transducers ’01 Eurosensors XV by : Ernst Obermeier
Download or read book Transducers ’01 Eurosensors XV written by Ernst Obermeier and published by Springer. This book was released on 2016-05-12 with total page 1763 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Conference is the premier international meeting for the presentation of original work addressing all aspects of the theory, design, fabrication, assembly, packaging, testing and application of solid-state sensors, actuators, MEMS, and microsystems.
Book Synopsis Nanostructured Carbon Electron Emitters and Their Applications by : Yahachi Saito
Download or read book Nanostructured Carbon Electron Emitters and Their Applications written by Yahachi Saito and published by CRC Press. This book was released on 2022-01-27 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon forms a variety of allotropes due to the diverse hybridization of s- and p-electron orbitals, including the time-honored graphite and diamond as well as new forms such as C60 fullerene, nanotubes, graphene, and carbyne. The new family of carbon isotopes—fullerene, nanotubes, graphene, and carbyne—is called “nanostructured carbon” or “nanocarbon.” These isotopes exhibit extreme properties such as ultrahigh mechanical strength, ultrahigh charge–carrier mobility, and high thermal conductivity, attracting considerable attention for their electronic and mechanical applications as well as for exploring new physics and chemistry in the field of basic materials science. Electron sources are important in a wide range of areas, from basic physics and scientific instruments to medical and industrial applications. Carbon nanotubes (CNTs) and graphene behave as excellent electron-field emitters owing to their exceptional properties and offer several benefits compared to traditional cathodes. Field emission (FE) produces very intense electron currents from a small surface area with a narrow energy spread, providing a highly coherent electron beam—a combination that not only provides us with the brightest electron sources but also explores a new field of electron beam–related research. This book presents the enthusiastic research and development of CNT-based FE devices and focuses on the fundamental aspects of FE from nanocarbon materials, including CNTs and graphene, and the latest research findings related to it. It discusses applications of FE to X-ray and UV generation and reviews electron sources in vacuum electronic devices and space thrusters. Finally, it reports on the new forms of carbon produced via FE from CNT.
Book Synopsis Semiconductor Manufacturing Handbook by : Hwaiyu Geng
Download or read book Semiconductor Manufacturing Handbook written by Hwaiyu Geng and published by McGraw Hill Professional. This book was released on 2005-05-18 with total page 914 pages. Available in PDF, EPUB and Kindle. Book excerpt: This handbook will provide engineers with the principles, applications, and solutions needed to design and manage semiconductor manufacturing operations. Consolidating the many complex fields of semiconductor fundamentals and manufacturing into one volume by deploying a team of world class specialists, it allows the quick look up of specific manufacturing reference data across many subdisciplines.
Book Synopsis Wafer-scale Alignment of Semiconducting Carbon Nanotubes from Solution by : Katherine Rose Jinkins
Download or read book Wafer-scale Alignment of Semiconducting Carbon Nanotubes from Solution written by Katherine Rose Jinkins and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes are unique one-dimensional materials that exhibit extraordinary properties, including high stability, large elastic modulus, and exceptional charge and thermal transport, making them promising candidates for future mechanical, optical, and electronic devices. Electrical measurements of individual nanotubes have demonstrated room-temperature ballistic conductance and 3× higher current density than state-of-the-art Si field-effect transistors (FETs). While these results are exciting; to achieve the high on-current required for future carbon nanotube technologies to become viable, electronic devices must incorporate multiple nanotubes aligned in parallel. Alignment is especially critical to minimize sheet resistance and reduce charge carrier scattering in devices. However, the alignment of carbon nanotubes at intermediate packing densities in a scalable technique has plagued the electronics community for decades. In this work, we develop, explore, and elucidate three possible solutions to this long-standing challenge. First, we elucidate the mechanism of the floating evaporative self-assembly (FESA) technique, in which stripes of aligned nanotubes are deposited onto substrates by dosing a carbon nanotube ink at a water/substrate interface. We track the key interfaces directly at the substrate during FESA and show that the nanotube alignment occurs from the buried ink/water interface. We also demonstrate improved control over the bandwidth and band spacing of aligned carbon nanotubes and align nanotubes across a 2.5 × 2.5 cm2 substrate, an important step towards high-volume production. Ultimately, though, FESA cannot yield uniform, continuous films of aligned nanotubes over the wafer-scale, so other techniques are explored. We use the understanding gained toward the FESA mechanism to develop another alignment technique, tangential flow interfacial self-assembly (TaFISA), to fabricate uniform films of highly aligned carbon nanotubes for short channel FETs. In this process, we demonstrate that an ink/water interface can induce liquid crystal assembly of carbon nanotubes. Flowing this two-dimensional nematic assembly of nanotubes, globally aligns the nanotubes. By translating a substrate through this flowing ink/water interface, uniform films of highly aligned (within ±5.7°) nanotubes are deposited across 10 cm wide substrates. Due to the underlying lyotropic liquid crystal phenomena, the nanotube ordering improves with increasing concentration and decreasing temperature. The exceptional alignment leads to excellent FET performance with high on-state current density averaging 520 [mu]A [mu]m−1 at a V[DS] of -0.6 V. We also perform a more detailed investigation of experimental parameters that can affect the interfacial assembly, including nanotube ink solvent, substrate surface water contact angle, and modification of the water subphase. We also study the effect of shear on nanotube ink, without the ink/water interface as used in the FESA and TaFISA technique. We elucidate the effect of shear rate on nanotube alignment and find that the alignment increases with increasing shear rate following a power law dependence. We also demonstrate control over the nanotube packing density by tailoring the carbon nanotube ink concentration and ink volume. FETs are fabricated with their charge transport direction parallel and perpendicular to the alignment. The parallel FETs exhibit 7× faster charge carrier mobility of 101 cm2 V−1 s−1, while also simultaneously displaying high on/off ratio of 105. Deposition conditions are extensively optimized to enable alignment within a ± 27° window at nearly ideal packing density of 50 nanotubes [mu]m−1 over large-area 10 × 10 cm2 substrates. These quasi-aligned films are promising candidates for long-channel FETs (e.g., in displays, sensors, and flexible electronics), where some misalignment is necessary to allow charge percolation. We additionally report our work utilizing solution-based shear to fabricate ultrathin films of aligned cellulose nanocrystals. Cellulose nanocrystals (CNC) exhibit excellent mechanical and piezoelectric properties, making this material attractive for use in high-performance coatings. Toward this goal, we use confined shear-based alignment to fabricate ultrathin films of aligned CNC. The shear rate is varied from 19 to 19000 s−1 to improve the half-width at half-maximum of the spread in CNC alignment from 130 to 30°. The CNC solution volume and concentration are both used to independently control the film height.
Book Synopsis Graphene, Carbon Nanotubes, and Nanostructures by : James E. Morris
Download or read book Graphene, Carbon Nanotubes, and Nanostructures written by James E. Morris and published by CRC Press. This book was released on 2017-07-28 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: Graphene, Carbon Nanotubes, and Nanostructures: Techniques and Applications offers a comprehensive review of groundbreaking research in nanofabrication technology and explores myriad applications that this technology has enabled. The book examines the historical evolution and emerging trends of nanofabrication and supplies an analytical understanding of some of the most important underlying nanofabrication technologies, with an emphasis on graphene, carbon nanotubes (CNTs), and nanowires. Featuring contributions by experts from academia and industry around the world, this book presents cutting-edge nanofabrication research in a wide range of areas. Topics include: CNT electrodynamics and signal propagation models Electronic structure calculations of a graphene–hexagonal boron nitride interface to aid the understanding of experimental devices based on these heterostructures How a laser field would modify the electronic structure and transport response of graphene, to generate bandgaps The fabrication of transparent CNT electrodes for organic light-emitting diodes Direct graphene growth on dielectric substrates, and potential applications in electronic and spintronic devices CNTs as a promising candidate for next-generation interconnect conductors CMOS–CNT integration approaches, including the promising localized heating CNT synthesis method CNTs in electrochemical and optical biosensors The synthesis of diamondoids by pulsed laser ablation plasmas generated in supercritical fluids, and possible applications The use of DNA nanostructures in lithography CMOS-compatible silicon nanowire biosensors The use of titanium oxide-B nanowires to detect explosive vapors The properties of protective layers on silver nanoparticles for ink-jet printing Nanostructured thin-film production using microreactors A one-stop reference for professionals, researchers, and graduate students working in nanofabrication, this book will also be useful for investors who want an overview of the current nanofabrication landscape.
Book Synopsis Fabrication and Analysis of Carbon Nanotube Based Emitters by : Vladimir Mancevski
Download or read book Fabrication and Analysis of Carbon Nanotube Based Emitters written by Vladimir Mancevski and published by . This book was released on 2011 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have advanced the state-of-the-art for nano-fabrication of carbon nanotube (CNT) based field emission devices, and have conducted experimental and theoretical investigations to better understand the reasons for the high reduced brightness achieved. We have demonstrated that once the CNT emitter failure modes are better understood and resolved, such CNT emitters can easily reach reduced brightness on the order of 109 A m−2 sr−1 V−1 and noise levels of about 1%. These results are about 10% better than the best brightness results from a nanotip emitter archived to date. Our CNT emitters have order of magnitude better reduced brightness than state-of-the-art commercial Schottky emitters. Our analytical models of field emission matched our experimental results well. The CNT emitter was utilized in a modified commercial scanning electron microscope (SEM) and briefly operated to image a sample. We also report a successful emission from a lateral CNT emitter element having a single suspended CNT, where the electron emission is from the CNT sidewall. The lateral CNT emitters have reduced brightness on the order of 108 A m−2 sr−1 V−1, about 10X less than the vertical CNT emitters we fabricated and analyzed. The characteristics of the lateral field emitter were analyzed for manually fabricated and directly grown CNT emitters. There was no significant difference in performance based on the way the CNT emitter was fabricated. We showed that the fabrication technique for making a single CNT emitter element can be scaled to an array of elements, with potential density of 106-107 CNT emitters per cm2. We also report a new localized, site selective technique for editing carbon nanotubes using water vapor and a focused electron beam. We have demonstrated the use of this technique to cut CNTs to length with 10s of nanometers precision and to etch selected areas from CNTs with 10s of nanometers precision. The use of this technique was demonstrated by editing a lateral CNT emitter. We have conducted investigations to demonstrate the effects of higher local water pressure on the CNT etching efficiency. This was achieved by developing a new method of localized gas delivery with a nano-manipulator.
