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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Design and Characterization of Resist and Mold Materials for Electron-Beam and Nanoimprint Lithography

Con, Celal 29 August 2011 (has links)
Electron beam lithography (EBL) and Nanoimprint Lithography (NIL) are the promising tools for today’s technology in terms of resolution capability, fidelity and cost of operation. Achieving highest possible resolution is a key concept for EBL where there is a huge request in applications of nanotechnology for sub-20 nm feature sizes. Defining features at these length scales is a challenge, and there is a large demand for resist that is not only capable of giving high resolution but also having low cost and ease of process. In this work I studied Polystyrene (PS) which is an alternative organic e-beam resist in terms of ease of process and resolution capability. I examined the process of electron-beam exposure and attempted to characterize the factors that affect the achieved resolution and sensitivity. Besides this work, I designed and fabricated a new type of mold for NIL since mold fabrication is a key factor for NIL technology. The resolution of NIL process depends on the mold features and polymer mold technology received great attention in terms of cost of fabrication and process, fidelity, and reliability. I used MD 700 Fluoropolymer as a new type of polymer mold which was believed to be a good candidate for the polymer mold of high throughput NIL.
62

On the throughput optimization of electron beam lithography systems /

Mulder, Elvira Hendrika, January 1991 (has links)
Thesis (doctoral)--Technische Universiteit Delft, 1991. / Summary in Dutch. "Stellingen" ([1] folded leaf) inserted. Vita. Includes bibliographical references (p. BR-1-BR-15).
63

Welding and repair of single crystal Ni-based superalloys /

Wang, Sizhao, January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2005. / Includes bibliographical references (p. 109-120). Also available in electronic format on the Internet.
64

Development of inorganic resists for electron beam lithography novel materials and simulations /

Jeyakumar, Augustin. January 2004 (has links) (PDF)
Thesis (Ph. D.)--School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, 2005. Directed by Clifford L. Henderson. / Brent Carter, Committee Member ; Clifford L. Henderson, Committee Chair ; Dennis Hess, Committee Member ; Peter Ludovice, Committee Member ; Kevin Martin, Committee Member. Vita. Includes bibliographical references.
65

Multi-beam-interference-based methodology for the fabrication of photonic crystal structures

Stay, Justin L. January 2009 (has links)
Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2010. / Committee Chair: Thomas K. Gaylord; Committee Member: Donald D. Davis; Committee Member: Gee-Kung Chang; Committee Member: Muhannad S. Bakir; Committee Member: Phillip N. First. Part of the SMARTech Electronic Thesis and Dissertation Collection.
66

Fabrication and characterization of a double torsional mechanical oscillator and its applications in gold micromass measurements

Lu, Wei, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
67

PMMA-Assisted Plasma Patterning of Graphene

Bobadilla, Alfredo D., Ocola, Leonidas E., Sumant, Anirudha V., Kaminski, Michael, Seminario, Jorge M. January 2018 (has links)
Microelectronic fabrication of Si typically involves high-temperature or high-energy processes. For instance, wafer fabrication, transistor fabrication, and silicidation are all above 500°C. Contrary to that tradition, we believe low-energy processes constitute a better alternative to enable the industrial application of single-molecule devices based on 2D materials. The present work addresses the postsynthesis processing of graphene at unconventional low temperature, low energy, and low pressure in the poly methyl-methacrylate- (PMMA-) assisted transfer of graphene to oxide wafer, in the electron-beam lithography with PMMA, and in the plasma patterning of graphene with a PMMA ribbon mask. During the exposure to the oxygen plasma, unprotected areas of graphene are converted to graphene oxide. The exposure time required to produce the ribbon patterns on graphene is 2 minutes. We produce graphene ribbon patterns with ∼50 nm width and integrate them into solid state and liquid gated transistor devices. / )e submitted manuscript has been created by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract DE-AC02-06CH11357. )e U.S. Government retains for itself, and others acting on its behalf, a paid-up nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the government. Funding text #2 )e Center for Nanoscale Materials was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract DE-AC02-06CH11357. )e authors also acknowledge financial support from Argonne National Laboratory’s Laboratory-Directed Research and Development Strategic Initiative. / Revisión por pares
68

Josephson junctions and devices fabricated by focused electron beam irradiation

Booij, Wilfred Edwin January 1997 (has links)
The irradiation of high Tc superconducting thin films with a focused electron beam, such as that obtained in a scanning transmission electron microscope (STEM), can result in the formation of a Josephson junction. The conditions required for the formation of these Josephson junctions in YBa2Cu3O7-d and related compounds are discussed as well as the physical properties of the irradiated material. From electrical transport measurements of individual Josephson junctions it was found that these junctions have a Superconductor/Normal/Superconductor (SNS) nature. Low temperature anneal studies indicate that Josephson junctions with optimum properties can be obtained by a combination of a high electron dose and subsequent low temperature anneal. Extremely high electron doses resulted in the formation of a purely resistive region. The electrical transport in such regions with a dimension of 200 nm in the direction of current transport is shown to be compatible with variable range hopping (VRH). Barriers with the same length but a finite superconducting transition temperature showed a low bias resistance that is significantly lowered due to proximity coupling. Using purely resistive regions in combination with Josephson junctions, devices consisting of two closely spaced Josephson junctions with a third terminal connected to the shared electrode were fabricated and characterised (minimum separation 20 nm). The distinct behaviour of the Josephson critical current with applied magnetic field (Ic(B)) of these devices was found to be well described by a newly developed model, which incorporates the effect of the static redistribution current in the shared electrode on the phase distribution of the Josephson junctions. An important finding is that the behaviour of the high critical current with applied magnetic field of two closely spaced junctions was found to be consistent with a model system consisting of a closely spaced Josephson junction and a resistive barrier. A three terminal device with Josephson junctions at small separations was found to have a significantly increased trans resistance when compared with the individual resistance of the Josephson junctions it constituted of. A number of illustrative examples of device structures realised with the focused electron beam irradiation technique are also included.
69

Vlastnosti nástřiku slitinou Inconel na austenitickou ocel zhotoveného technologií kinetického naprašování po přetavení elektronovým paprskem / Properties of Inconel alloy coating on austenitic steel made by cold-spray technology after electron beam remelting

Chlupová, Monika January 2020 (has links)
This diploma thesis is focused on description of the properties of a layer of Inconel 718 applied on austenitic steel AISI 304 by the Cold Spray and subsequently remelted by electron beam. The first part presents the Cold Spray with its properties, advantages and disadvantages, and also describes the principle of electron beam remelting and other possible uses of electron beam, for example welding, drilling, heat treatment etc. The second part describes the material and the methods used for the preparation and evaluation of the samples. There are evaluated the porosity, microstructure and microhardness of the layers applied by the Cold Spray and these properties are further compared with the properties of the same layers remelted by electron beam. In conclusion, the results of the porosity of the layers applied by the Cold Spray are discussed with the literature and the results of electron beam remelting are only partially described here, because it was not possible to find literature about this topic. There are also suggestions for further research of the properties of this layers, which is necessary to know before implementing this method of producing layers for commercial production.
70

Electron beam irradiation of polystyrene/poly(vinyl methyl ether) blends

Pietri, Valerie 29 July 2009 (has links)
The effects of electron beam radiation on the rheological behavior of a polystyrene/poly(vinyl methyl ether) blend as a function of absorbed dose, composition, and temperature, were investigated. The purpose of this research has been to modify the viscosity of polystyrene by studying the influences of the addition of a small amount of poly(vinyl methyl ether), combined with the exposure of the blends to low radiation doses. It is shown that the crosslinking behavior, in terms of the changes in the viscosity, is more pronounced and significant for the highest PVME content system composed of 10 wt % PVME. The other blends under consideration in this study do not display significant modifications in their rheological response after irradiation. The effects of radiation and composition on the temperature dependence of the viscosity is illustrated using the Arrhenius Law. The results obtained, in terms of flow activation energy, Ea, show that no real changes occurred due to radiation. On the other hand, it is found that the flow activation energy is strongly dependent on the blend composition. The phase separation temperature as a function of radiation dose and composition is also examined. It is shown that the most noticeable change occurs at a radiation dose of 10 Mrads, the phase separation temperature increasing also as PVME content increases in the blend composition. / Master of Science

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