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Estudo de técnicas de nanofabricação aplicada à filmes semicondutores; Development of nanofabrication techniques applied to semiconductor films

Alves, Marcus Vinícius
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 29/03/1999 PT
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Este trabalho teve como objetivo principal o estudo de técnicas de nanofabricação aplicadas a filmes semicondutores do grupo 111-V, crescidos pela técnica de epitaxia por feixe molecular. Padrões, visando o domínio da técnica e a produção de nano-estruturas foram criados em filmes de GaAs utilizando-se a técnica de litografia por feixe de elétrons e ataques químicos. Os padrões foram gerados a partir de um software especial de controle que, acoplado ao microscópio eletrônico de varredura, através de uma interface, permite o controle externo da varredura x-y do feixe de elétrons. Estudamos o comportamento da espessura do filme de elétron-resiste poli (metacrilato de metila) (PMMA) em função da temperatura, aplicando soluções com pesos moleculares variados sobre filmes semicondutores, dissolvidos em Xileno, Monoclorobenzeno e Acetona. Investigamos o uso do ultra-som nos processos de revelação do PMMA e no ataque químico de superfícies de GaAs. Através da análise do ataque químico empregando várias formulações a base de ácidos em GaAs (100) e (3 1 l)A e B, determinamos a velocidade de ataque em cada caso, classificando as propriedades obtidas para a superfície. Em GaAs (100) avaliamos a dependência entre a rugosidade da face atacada e o tempo de ataque para uma solução de NH4OH:H2O (pH=7). Os resultados por nós obtidos formam um conjunto de dados que servirão de apoio a trabalhos futuros...

Micro- and nanofabrication methods in nanotechnological medical and pharmaceutical devices

Betancourt, Tania; Brannon-Peppas, Lisa
Fonte: Dove Medical Press Publicador: Dove Medical Press
Tipo: Artigo de Revista Científica
EN
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Micro- and nanofabrication techniques have revolutionized the pharmaceutical and medical fields as they offer the possibility for highly reproducible mass-fabrication of systems with complex geometries and functionalities, including novel drug delivery systems and bionsensors. The principal micro- and nanofabrication techniques are described, including photolithography, soft lithography, film deposition, etching, bonding, molecular self assembly, electrically induced nanopatterning, rapid prototyping, and electron, X-ray, colloidal monolayer, and focused ion beam lithography. Application of these techniques for the fabrication of drug delivery and biosensing systems including injectable, implantable, transdermal, and mucoadhesive devices is described.

From Cleanroom to Desktop: Emerging Micro-Nanofabrication Technology for Biomedical Applications

Pan, Tingrui; Wang, Wei
Fonte: Springer US Publicador: Springer US
Tipo: Artigo de Revista Científica
EN
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This review is motivated by the growing demand for low-cost, easy-to-use, compact-size yet powerful micro-nanofabrication technology to address emerging challenges of fundamental biology and translational medicine in regular laboratory settings. Recent advancements in the field benefit considerably from rapidly expanding material selections, ranging from inorganics to organics and from nanoparticles to self-assembled molecules. Meanwhile a great number of novel methodologies, employing off-the-shelf consumer electronics, intriguing interfacial phenomena, bottom-up self-assembly principles, etc., have been implemented to transit micro-nanofabrication from a cleanroom environment to a desktop setup. Furthermore, the latest application of micro-nanofabrication to emerging biomedical research will be presented in detail, which includes point-of-care diagnostics, on-chip cell culture as well as bio-manipulation. While significant progresses have been made in the rapidly growing field, both apparent and unrevealed roadblocks will need to be addressed in the future. We conclude this review by offering our perspectives on the current technical challenges and future research opportunities.

Maskless and low-destructive nanofabrication on quartz by friction-induced selective etching

Song, Chenfei; Li, Xiaoying; Cui, Shuxun; Dong, Hanshan; Yu, Bingjun; Qian, Linmao
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 27/03/2013 EN
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A low-destructive friction-induced nanofabrication method is proposed to produce three-dimensional nanostructures on a quartz surface. Without any template, nanofabrication can be achieved by low-destructive scanning on a target area and post-etching in a KOH solution. Various nanostructures, such as slopes, hierarchical stages and chessboard-like patterns, can be fabricated on the quartz surface. Although the rise of etching temperature can improve fabrication efficiency, fabrication depth is dependent only upon contact pressure and scanning cycles. With the increase of contact pressure during scanning, selective etching thickness of the scanned area increases from 0 to 2.9 nm before the yield of the quartz surface and then tends to stabilise after the appearance of a wear. Refabrication on existing nanostructures can be realised to produce deeper structures on the quartz surface. Based on Arrhenius fitting of the etching rate and transmission electron microscopy characterization of the nanostructure, fabrication mechanism could be attributed to the selective etching of the friction-induced amorphous layer on the quartz surface. As a maskless and low-destructive technique, the proposed friction-induced method will open up new possibilities for further nanofabrication.

Effect of crystal plane orientation on the friction-induced nanofabrication on monocrystalline silicon

Yu, Bingjun; Qian, Linmao
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 25/03/2013 EN
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Although monocrystalline silicon reveals strong anisotropic properties on various crystal planes, the friction-induced nanofabrication can be successfully realized on Si(100), Si(110), and Si(111) surfaces. Under the same loading condition, the friction-induced hillock produced on Si(100) surface is the highest, while that produced on Si(111) surface is the lowest. The formation mechanism of hillocks on various silicon crystal planes can be ascribed to the structural deformation of crystal matrix during nanoscratching. The silicon crystal plane with lower elastic modulus can lead to larger pressed volume during sliding, facilitating more deformation in silicon matrix and higher hillock. Meanwhile, the structures of Si-Si bonds on various silicon crystal planes show a strong effect on the hillock formation. High density of dangling bonds can cause much instability of silicon surface during tip disturbing, which results in the formation of more amorphous silicon and high hillock during the friction process. The results will shed new light on nanofabrication of monocrystalline silicon.

Silicon Micro- and Nanofabrication for Medicine

Fine, Daniel; Grattoni, Alessandro; Goodall, Randy; Bansal, Shyam S.; Chiappini, Ciro; Hosali, Sharath; van de Ven, Anne L.; Srinivasan, Srimeenkashi; Liu, Xuewu; Godin, Biana; Brousseau, Louis; Yazdi, Iman K.; Fernandez-Moure, Joseph; Tasciotti, Ennio; W
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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This manuscript constitutes a review of several innovative biomedical technologies fabricated using the precision and accuracy of silicon micro- and nanofabrication. The technologies to be reviewed are subcutaneous nanochannel drug delivery implants for the continuous tunable zero-order release of therapeutics, multi-stage logic embedded vectors for the targeted systemic distribution of both therapeutic and imaging contrast agents, silicon and porous silicon nanowires for investigating cellular interactions and processes as well as for molecular and drug delivery applications, porous silicon (pSi) as inclusions into biocomposites for tissue engineering, especially as it applies to bone repair and regrowth, and porous silica chips for proteomic profiling. In the case of the biocomposites, the specifically designed pSi inclusions not only add to the structural robustness, but can also promote tissue and bone regrowth, fight infection, and reduce pain by releasing stimulating factors and other therapeutic agents stored within their porous network. The common material thread throughout all of these constructs, silicon and its associated dielectrics (silicon dioxide, silicon nitride, etc.), can be precisely and accurately machined using the same scalable micro- and nanofabrication protocols that are ubiquitous within the semiconductor industry. These techniques lend themselves to the high throughput production of exquisitely defined and monodispersed nanoscale features that should eliminate architectural randomness as a source of experimental variation thereby potentially leading to more rapid clinical translation.

Desktop Nanofabrication with Massively Multiplexed Beam Pen Lithography

Liao, Xing; Brown, Keith A.; Schmucker, Abrin L.; Liu, Guoliang; He, Shu; Shim, Wooyoung; Mirkin, Chad A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
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The development of a lithographic method that can rapidly define nanoscale features across centimeter-scale surfaces has been a long standing goal of the nanotechnology community. If such a ‘desktop nanofab’ could be implemented in a low-cost format, it would bring the possibility of point-of-use nanofabrication for rapidly prototyping diverse functional structures. Here we report the development of a new tool that is capable of writing arbitrary patterns composed of diffraction-unlimited features over square centimeter areas that are in registry with existing patterns and nanostructures. Importantly, this instrument is based on components that are inexpensive compared to the combination of state-of-the-art nanofabrication tools that approach its capabilities. This tool can be used to prototype functional electronic devices in a mask-free fashion in addition to providing a unique platform for performing high throughput nano- to macroscale photochemistry with relevance to biology and medicine.

Maskless micro/nanofabrication on GaAs surface by friction-induced selective etching

Tang, Peng; Yu, Bingjun; Guo, Jian; Song, Chenfei; Qian, Linmao
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 04/02/2014 EN
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In the present study, a friction-induced selective etching method was developed to produce nanostructures on GaAs surface. Without any resist mask, the nanofabrication can be achieved by scratching and post-etching in sulfuric acid solution. The effects of the applied normal load and etching period on the formation of the nanostructure were studied. Results showed that the height of the nanostructure increased with the normal load or the etching period. XPS and Raman detection demonstrated that residual compressive stress and lattice densification were probably the main reason for selective etching, which eventually led to the protrusive nanostructures from the scratched area on the GaAs surface. Through a homemade multi-probe instrument, the capability of this fabrication method was demonstrated by producing various nanostructures on the GaAs surface, such as linear array, intersecting parallel, surface mesas, and special letters. In summary, the proposed method provided a straightforward and more maneuverable micro/nanofabrication method on the GaAs surface.

Nanofabrication for the Analysis and Manipulation of Membranes

Kelly, Christopher V.; Craighead, Harold G.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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Recent advancements and applications of nanofabrication have enabled the characterization and control of biological membranes at submicron scales. This review focuses on the application of nanofabrication towards the nanoscale observing, patterning, sorting, and concentrating membrane components. Membranes on living cells are a necessary component of many fundamental cellular processes that naturally incorporate nanoscale rearrangement of the membrane lipids and proteins. Nanofabrication has advanced these understandings, for example, by providing 30 nm resolution of membrane proteins with metal-enhanced fluorescence at the tip of a scanning probe on fixed cells. Naturally diffusing single molecules at high concentrations on live cells have been observed at 60 nm resolution by confining the fluorescence excitation light through nanoscale metallic apertures. The lateral reorganization on the plasma membrane during membrane-mediated signaling processes has been examined in response to nanoscale variations in the patterning and mobility of the signal-triggering molecules. Further, membrane components have been separated, concentrated, and extracted through on-chip electrophoretic and microfluidic methods. Nanofabrication provides numerous methods for examining and manipulating membranes for both greater understandings of membrane processes as well as for the application of membranes to other biophysical methods.

Tip-Based Nanofabrication of Arbitrary Shapes of Graphene Nanoribbons for Device Applications

Hu, Huan; Banerjee, Shouvik; Estrada, David; Bashir, Rashid; King, William P.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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Graphene nanoribbons (GNRs) have promising applications in future nanoelectronics, chemical sensing and electrical interconnects. Although there are quite a few GNR nanofabrication methods reported, a rapid and low-cost fabrication method that is capable of fabricating arbitrary shapes of GNRs with good-quality is still in demand for using GNRs for device applications. In this paper, we present a tip-based nanofabrication method capable of fabricating arbitrary shapes of GNRs. A heated atomic force microscope (AFM) tip deposits polymer nanowires atop a CVD-grown graphene surface. The polymer nanowires serve as an etch mask to define GNRs through one step of oxygen plasma etching similar to a photoresist in conventional photolithography. Various shapes of GNRs with either linear or curvilinear features are demonstrated. The width of the GNR is around 270 nm and is determined by the width of the depositing polymer nanowire, which we estimate can be scaled down 15 nms. We characterize our TBN-fabricated GNRs using Raman spectroscopy and I-V measurements. The measured sheet resistances of our GNRs fall within the range of 1.65 kΩ/□−1 – 2.64 kΩ/□−1, in agreement with previously reported values. Furthermore, we determined the high-field breakdown current density of GNRs to be approximately 2.94×108 A/cm2. This TBN process is seamlessly compatible with existing nanofabrication processes...

Use of Thin Sectioning (Nanoskiving) to Fabricate Nanostructures for Electronic and Optical Applications

Lipomi, Darren J.; Martinez, Ramses V.; Whitesides, George McClelland
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica
EN_US
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This Review discusses nanoskiving—a simple and inexpensive method of nanofabrication, which minimizes requirements for access to cleanrooms and associated facilities, and which makes it possible to fabricate nanostructures from materials, and of geometries, to which more familiar methods of nanofabrication are not applicable. Nanoskiving requires three steps: 1) deposition of a metallic, semiconducting, ceramic, or polymeric thin film onto an epoxy substrate; 2) embedding this film in epoxy, to form an epoxy block, with the film as an inclusion; and 3) sectioning the epoxy block into slabs with an ultramicrotome. These slabs, which can be 30 nm–10 μm thick, contain nanostructures whose lateral dimensions are equal to the thicknesses of the embedded thin films. Electronic applications of structures produced by this method include nanoelectrodes for electrochemistry, chemoresistive nanowires, and heterostructures of organic semiconductors. Optical applications include surface plasmon resonators, plasmonic waveguides, and frequency-selective surfaces.; Chemistry and Chemical Biology

Accurate nanofabrication techniques for high-index-contrast microphotonic devices

Barwicz, Tymon
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 199 p.; 25552478 bytes; 25552006 bytes; application/pdf; application/pdf
ENG
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High-refractive-index-contrast microphotonic devices provide strong light confinement allowing for sharp waveguide bends and small dielectric optical resonators. They allow dense optical integration and unique applications to optical filters and sensors but present exceptional complications in design and fabrication. In this work, nanofabrication techniques are developed to address the two main challenges in fabrication of high-index contrast microphotonic devices: sidewall roughness and dimensional accuracy. The work focuses on fabrication of optical add-drop filters based on high-index contrast microring-resonators. The fabrication is based on direct-write scanning-electronbeam lithography. A sidewall-roughness characterization and optimization scheme is developed as is the first three-dimensional analysis of scattering losses due to sidewall roughness. Writing strategy in scanning-electron-beam lithography and absolute and relative dimensional control are addressed. The nanofabrication techniques developed allowed fabrication of the most advanced microring add-drop-filters reported in the literature. The sidewall-roughness standard deviation was reduced to 1.6 nm.; (cont.) The field polarization and the waveguide cross-sections minimizing scattering losses are presented. An absolute dimensional control accuracy of 5 nm is demonstrated. Microring resonators with average ring-waveguide widths matched to 26 pm to a desired relative width-offset are reported.; by Tymon Barwicz.; Thesis (Ph. D.)--Massachusetts Institute of Technology...

Accurate Nanofabrication Techniques for High-Index-Contrast Microphotonic Devices

Barwicz, Tymon
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Relatório Formato: 25552132 bytes; application/pdf
EN
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High-refractive-index-contrast microphotonic devices provide strong light confinement allowing for sharp waveguide bends and small dielectric optical resonators. They allow dense optical integration and unique applications to optical filters and sensors but present exceptional complications in design and fabrication. In this work, nanofabrication techniques are developed to address the two main challenges in fabrication of high-indexcontrast microphotonic devices: sidewall roughness and dimensional accuracy. The work focuses on fabrication of optical add-drop filters based on high-indexcontrast microring-resonators. The fabrication is based on direct-write scanning-electronbeam lithography. A sidewall-roughness characterization and optimization scheme is developed as is the first three-dimensional analysis of scattering losses due to sidewall roughness. Writing strategy in scanning-electron-beam lithography and absolute and relative dimensional control are addressed. The nanofabrication techniques developed allowed fabrication of the most advanced microring add-drop-filters reported in the literature. The sidewall-roughness standarddeviation was reduced to 1.6 nm. The field polarization and the waveguide cross-sections minimizing scattering losses are presented. An absolute dimensional control accuracy of 5 nm is demonstrated. Microring resonators with average ring-waveguide widths matched to 26 pm to a desired relative width-offset are reported.; Thesis Supervisor: Henry I. Smith Title: Joseph F. and Nancy P. Keithley Professor of Electrical Engineering Thesis Supervisor: Harry L. Tuller Title: Professor of Ceramics and Electronic Materials

Low-cost fabrication technologies for nanostructures: state-of-the-art and potential

Santos, A.; Deen, M.J.; Marsal, L.F.
Fonte: IOP Publishing Publicador: IOP Publishing
Tipo: Artigo de Revista Científica
Publicado em //2015 EN
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In the last decade, some low-cost nanofabrication technologies used in several disciplines of nanotechnology have demonstrated promising results in terms of versatility and scalability for producing innovative nanostructures. While conventional nanofabrication technologies such as photolithography are and will be an important part of nanofabrication, some low-cost nanofabrication technologies have demonstrated outstanding capabilities for large-scale production, providing high throughputs with acceptable resolution and broad versatility. Some of these nanotechnological approaches are reviewed in this article, providing information about the fundamentals, limitations and potential future developments towards nanofabrication processes capable of producing a broad range of nanostructures. Furthermore, in many cases, these low-cost nanofabrication approaches can be combined with traditional nanofabrication technologies. This combination is considered a promising way of generating innovative nanostructures suitable for a broad range of applications such as in opto-electronics, nano-electronics, photonics, sensing, biotechnology or medicine.; A Santos, MJ Deen and LF Marsal

Nanofabrication on unconventional substrates using transferred hard masks

Li, Luozhou; Bayn, Igal; Lu, Ming; Nam, Chang-Yong; Schröder, Tim; Stein, Aaron; Harris, Nicholas C.; Englund, Dirk
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em 15/01/2015 EN
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A major challenge in nanofabrication is to pattern unconventional substrates that cannot be processed for a variety of reasons, such as incompatibility with spin coating, electron beam lithography, optical lithography, or wet chemical steps. Here, we present a versatile nanofabrication method based on re-usable silicon membrane hard masks, patterned using standard lithography and mature silicon processing technology. These masks, transferred precisely onto targeted regions, can be in the millimetre scale. They allow for fabrication on a wide range of substrates, including rough, soft, and non-conductive materials, enabling feature linewidths down to 10 nm. Plasma etching, lift-off, and ion implantation are realized without the need for scanning electron/ion beam processing, UV exposure, or wet etching on target substrates.

Friction-induced nanofabrication method to produce protrusive nanostructures on quartz

Song, Chenfei; Li, Xiaoying; Yu, Bingjun; Dong, Hanshan; Qian, Linmao; Zhou, Zhongrong
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 07/04/2011 EN
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In this paper, a new friction-induced nanofabrication method is presented to fabricate protrusive nanostructures on quartz surfaces through scratching a diamond tip under given normal loads. The nanostructures, such as nanodots, nanolines, surface mesas and nanowords, can be produced on the target surface by programming the tip traces according to the demanded patterns. The height of these nanostructures increases with the increase of the number of scratching cycles or the normal load. Transmission electron microscope observations indicated that the lattice distortion and dislocations induced by the mechanical interaction may have played a dominating role in the formation of the protrusive nanostructures on quartz surfaces. Further analysis reveals that during scratching, a contact pressure ranged from 0.4Py to Py (Py is the critical yield pressure of quartz) is apt to produce protuberant nanostructures on quartz under the given experimental conditions. Finally, it is of great interest to find that the protrusive nanostructures can be selectively dissolved in 20% KOH solution. Since the nanowords can be easily 'written' by friction-induced fabrication and 'erased' through selective etching on a quartz surface, this friction-induced method opens up new opportunities for future nanofabrication.

Chip-scale nanofabrication of single spins and spin arrays in diamond

Toyli, David M.; Weis, Christoph D.; Fuchs, Gregory D.; Schenkel, Thomas; Awschalom, David D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We demonstrate a technique to nanofabricate nitrogen vacancy (NV) centers in diamond based on broad-beam nitrogen implantation through apertures in electron beam lithography resist. This method enables high-throughput nanofabrication of single NV centers on sub-100 nm length scales. Secondary ion mass spectroscopy (SIMS) measurements facilitate depth profiling of the implanted nitrogen to provide three-dimensional characterization of the NV center spatial distribution. Measurements of NV center coherence with on-chip coplanar waveguides suggest a pathway for incorporating this scalable nanofabrication technique in future quantum applications.; Comment: This paper has been withdrawn by the authors. 14 pages, 3 figures; Posting has been removed due to editorial request from ACS Nano Letters; This version has been removed by arXiv admin because it contains an inappropriate withdrawal notice

Electron beam lithography for nanofabrication

Rius Suñé, Gemma
Fonte: Bellaterra : Universitat Autònoma de Barcelona, Publicador: Bellaterra : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf; application/pdf
Publicado em //2008 ENG; ENG
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Consultable des del TDX; Títol obtingut de la portada digitalitzada; La litografía por haz de electrones (Electron Beam Lithography, EBL) se ha consolidado como una de las técnicas más eficaces que permiten definir motivos en el rango nanométrico. Su implantación ha permitido la nanofabricación de estructuras y dispositivos para su uso en el campo de la nanotecnología y la nanociencia. La EBL se basa en la definición de motivos submicrónicos mediante el rastreo de un haz energético de electrones sobre una resina. La naturaleza de los electrones y el desarrollo the haces extremadamente finos y su control preciso establecen la plataforma ideal para los requerimientos de la Nanofabricación. El uso de la EBL para el desarrollo de un gran número de nanoestructuras, nanodispositivos y nanosistemas ha sido, y continúa siendo, crucial para las aplicaciones de producción de máscaras, prototipaje o dispositivos discretos para la investigación fundamental. Su éxito radica en la alta resolución, flexibilidad y compatibilidad de la EBL con otros procesos de fabricación convencionales. El objetivo de esta tesis es el avance en el conocimiento, desarrollo y aplicación de la EBL en las areas de los micro/nanosistemas y la nanoelectrónica. El presente documento refleja parte del trabajo realizado en el Laboratorio de Nanofabricación del Instituto de Microelectrónica de Barcelona IMB-CNM-CSIC durante los últimos cinco años. Debido a la falta de experiencia previa en el IMB en la utilización de la EBL...

Nanofabrication using focused ion beam

Latif, Adnan
Fonte: University of Cambridge; Department of Materials Science and Metallurgy Publicador: University of Cambridge; Department of Materials Science and Metallurgy
Tipo: Thesis; Doctoral Formato: 2401621 bytes; application/pdf
EN
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Focused ion beam (FIB) technique uses a focused beam of ions to scan the surface of a specimen, analogous to the way scanning electron microscope (SEM) utilizes electrons. Recent developments in the FIB technology have led to beam spot size below 10 nm, which makes FIB suitable for nanofabrication. This project investigated the nanofabrication aspect of the FIB technique, with device applications perspective in several directions. Project work included construction of an in-situ FIB electrical measurement system and development of its applications, direct measurements of nanometer scale FIB cuts and fabrication and testing of lateral field emission devices. Research work was performed using a number of materials including Al, Cr, SiO2, Si3N4 and their heterostructures. Measurements performed included in-situ resistometric measurements, which provided milled depth information by monitoring the resistance change of a metal track while ion milling it. The reproducibly of this method was confirmed by repeating experiments and accuracy was proven by atomic force microscopy (AFM). The system accurately monitored the thickness of 50 nm wide and 400 nm thick (high aspect ratio) Nb tracks while ion milling them. Direct measurements of low aspect ratio nanometer scale FIB cuts were performed using AFM on single crystal Si...

Investigation of atmospheric microplasma jet for nanofabrication

Yurchenko, Konstantin
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
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The last decade has seen an immense amount of research exploring advanced nanofabrication techniques. Many efforts on this front have moved closer to realization of industrially viable nanofabrication, i.e. nanomanufacturing. Plasma-assisted processes have proven to be particularly suitable for nanofabrication due to a non-equilibrium condition that offers high concentration of chemically reactive species at low gas temperatures. Recently, cost-effective atmospheric plasma technologies have been a subject of intense research. The possibility of producing plasma environments at atmospheric pressure similar to those found at low-pressure offer additional advantages for industrial implementation of nanofabrication processes and surface treatment. Atmospheric pressure equates to lower processing cost, higher reaction rates, and increased throughput. An effective way to produce plasmas at atmospheric pressure while maintaining a high degree of process flexibility is to confine them in sub-millimeter cavities, i.e. microplasmas. In this contribution, we have developed atmospheric microplasma systems and their applicability to nanofabrication is being considered. Contemporary research reports that plasma properties in the sub-millimeter range possess peculiar characteristics and a unique chemistry. The experiments described in this thesis aim to investigate these qualities. Discharge properties are examined using current-voltage measurements...