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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.
131

Photoluminescence and kinetics of zinc oxide doped with rare earths

Patel, Bhavnesh. January 1998 (has links)
Thesis (M.S.)--Ohio University, August, 1998. / Title from PDF t.p.
132

Picosecond time-resolved photoluminescence of zinc oxide single crystals, films and nanoparticles /

Wilkinson, John Henry, January 2003 (has links)
Thesis (Ph.D.)--Wake Forest University. Dept. of Physics, 2003. / Vita. Includes bibliographical references.
133

Nanogenerators

Song, Jinhui. January 2008 (has links)
Thesis (Ph.D.)--Materials Science and Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Zhong lin Wang; Committee Member: Christopher J. Summers; Committee Member: Kenneth A. Gall; Committee Member: Robert L. Snyder; Committee Member: Russell D. Dupuis.
134

Zno nanowires for sensing and power generation for system-on-package technology

Liu, Jin. January 2008 (has links)
Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Tummala, Rao; Committee Co-Chair: Wang, Zhong Lin; Committee Member: Brand, Oliver; Committee Member: Chang, Gee-Kung; Committee Member: Ghovanloo, Maysam; Committee Member: Wong, Ching-Ping. Part of the SMARTech Electronic Thesis and Dissertation Collection.
135

A study of the reduction of zinc oxide by hydrogen and methane

Weirich, Frederick Adam. January 1926 (has links) (PDF)
Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1926. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed Sept. 16, 2009). Includes bibliographical references (p. 20-21).
136

Engineering nanomaterials with a combined electrochemical and molecular biomimetic approach /

Dai, Haixia. January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 97-106).
137

Mechanical characterization of thin films /

Huang, Bin. January 2005 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references. Also available in electronic version.
138

Optical properties of ZnO thin film : raman spectroscopy, optical reflection, photoluminescence and stimulated emission /

Xie, Xing. January 2005 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 82). Also available in electronic version.
139

Efeito da pressão em filmes finos de ZnO:Al por RF Magnetron sputtering reativo /

Chaves, Michel. January 2014 (has links)
Orientador: José Roberto Ribeiro Bortoleto / Banca: José Humberto da Silva / Banca: Adriana de Oliveira Delgado / O Programa de Pós Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi / Resumo: Filme finos de AZO foram sintetizados sobre substratos de vidro utilizando um alvo de Zn-Al (5% at Al) com 99,999% de pureza através da técnica RF magnetron sputtering reativo a temperatura ambiente. As propriedades estruturais, elétricas, ópticas e morfológicas foram investigadas em função da variação da pressão de argônio no intervalo de 10 a 50 mTorr. As análises de DXR revelaram que os filmes obtidos são policristalinos come estrutura hexagonal wurtzita e orientação preferencial no plano (002). Além disso, mostrou que o aumento da pressão, reduziu os valores tensão e ocasionou o aumento da presença de vazios entre os grãos. Para todos os filmes finos obtidos as medidas de transmitância óptica apresentaram valores acima de 80% na região visível do espectro entre 500-700 nm. Já os valores de gap óptico decresceram de 3,68 para 3,55 eV com o aumento da pressão. O filme sintetizado a 10 mTorr apresentou os melhores resultados em termos de densidade de portadores e mobilidade elétrica, sendo os valores 2,68 x 10 cm-3/Vs, respectivamente / Abstract: Aluminum zinc oxide (AZO) thin films were synthesized on glass substrates by radiofrequency (RF) magnetron sputtering of a Zn-Al (5at% Al) target of 99.999% purity at ambient temperature. The structural, electrical, optical and morphological properties of the films were investigated as a function of the argon pressure, which was varied from 10 to 50 mTorr. X-ray diffraction (XRD) analyses revealed that the films obtained are polycrystalline with a hexagonal wurtzite structure with a preferential orientation in the (002) plane. In addition, it was show than an increase in pressure reduced the tension and produced an increase in the inter-grain spaces. For all of the films produced optical transmission was above 80% in the visible region (wavelength between 500 nm and 700 nm). As the system pressure was increased the optical gap fell from 3.68 to 3.55 eV. The film synthesized at 10 mTorr presented the best results in terms of the carrier density and electrical mobility, which were 2.68 x 10 cm-3 and 3.0 cm2/Vs, respectively / Mestre
140

Cation and anion doping of ZnO thin films by spray pyrolysis

Rashidi, Nazanin January 2015 (has links)
ZnO is an n-type semiconducting material with high optical transparency in the visible range (400 - 750 nm) of the electromagnetic spectrum. When doped with group 13 or 14 metal oxides, ZnO exhibits almost metallic electrical conductivity. ZnO thin films have been recognised as promising alternative material for the currently widely-used but expensive indium oxide in the form of indium tin oxide (ITO), in terms of their low cost and the high abundance of zinc. At the moment, even the best solution-processed ZnO films still can not compete for ITO replacement especially in solar energy utilization and OLED lighting applications, and the performance of ZnO films needs to be further improved. The objective of this work was to enhance the electrical and optical properties of spray pyrolysed ZnO thin films by simultaneous cation and anion doping. This was achieved by growing several series of undoped, single-doped, and co-doped ZnO thin films over a wide range of conditions, in order to understand the growth behaviour of undoped and doped ZnO, and to establish the optimum growth procedure. Spray pyrolysis process has advantages over vacuum-based techniques in terms of its low-cost, high deposition rate, simple procedure and can be applied for the production of large area thin films. Various techniques were employed to characterize the properties of the prepared thin films, and thus determine the optimum growth conditions (i.e. X-ray difiraction (XRD), Xray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron microscopy (SEM), UV-Vis-NIR spectroscopy and Hall effect measurement). The growth of doped ZnO on glass substrates using Si and F as dopants, yielded highly conducting and transparent thin films. The co-doped thin films exhibited distinct widening of band gap upon increasing deposition temperature and doping concentration as a result of increasing electron concentration up to 4.8 x 10<sup>20</sup> cm<sup>-3</sup> upon doping with Si and F at the same time. The resistivity of the films deposited from Zn(acac)<sub>2</sub> &middot; xH<sub>2</sub>O solutions and at the optimum temperature of 450 &deg;C, was found to decrease from 4.6 x 10<sup>-2</sup> &ohm;cm for the best undoped ZnO film to 3.7 x 10<sup>-3</sup> &ohm;cm, upon doping with 3&percnt; Si. The films co-doped with Si and F in the ratios of [Si] / [Zn]= 3 - 4 mol&percnt; and [F] / [Zn]=30 - 40 mol&percnt; were the most conducting (p &Tilde; 2.0 x 10<sup>-3</sup> &ohm;cm). The associated optical transmittance of co-doped ZnO was above 85&percnt; in the whole visible range. Results compare favourably with In-doped ZnO deposited under similar conditions. Si&plus;F co-doped ZnO films offer a suitable replacement for ITO in many applications such as LCD and touch screen displays.

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