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Deposition of fluorinated amorphous carbon thin films as a low-dielectric-constant material
No full textFluorinated amorphous carbon thin films (a-C:F) are deposited using inductively coupled plasma chemical vapor deposition with various flow-rare ratios of CH4:CF4 gases for ultralarge-scale integrated intermetal dielectric applications. The accurate composition of the thin films are quantitatively analyzed using elastic recoil detection-time of flight. The incorporation of fluorine is saturated at about 25 atom % by increasing the CF4 flow rate. The dielectric constant decreases to 2.4 and the refractive index of the film is reduced to 1.35 as the CF4 flow rate increases. Also, it is observed that the C-F bonding configuration changes from an unsaturated C-F bond to C-F-2 and C-F-3 bonds with growing CF4 flow rate. Thus, the reduction mechanism of the dielectric constant can be obtained by variation of the C-F, bonding configuration as well as the incorporation of fluorine. (C) 1999 The Electrochemical Society. S0013-4651(98)11-028-5. All rights reserved.This work was financially supported by the Ministry of Education through the Interuniversity Semiconductor Research Center(ISRC 97-E-1060) in Seoul National University and by the International Collaborative Research Program of the Ministry of Science and Technology.
Korea Advanced Institute of Science and Technology assisted in meeting the publication costs of this article
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
γ-Glycidoxypropyltrimethoxysilane-Chelated metal alkoxide 겔 막의 광표백
No full text학위논문(석사) - 한국과학기술원 : 재료공학과, 2000.2, [ xii, 147, [7] p. ]γ-glycidoxypropyltrimethoxysilane (GPTS) is a useful precursor for sol-gel preparation of inorganic-organic hybrid materials. The silica network is formed by hydrolysis and condensation of a methoxy radical in the presence of water and poly(ethylene oxide) polymeric network is made by polymerization of epoxy ring with an addition of polymerization initiator. Crack free thick films of the silica PEO hybrid materials can be made due to flexibility of polymer in silica network. On the other hand, metal alkoxides are very reactive to hydrolysis and condensation. Thus, the chemical modification of metal alkoxides with organic additives such as β-diketones and β-ketoesters is known to be very effective method to control the reactivity of metal alkoxides and final properties of gels. These chemically modified metal alkoxides present optical absorption band in the UV-region due to the photoexcited π- transition state of 6-membered chelate ring. A number of photochemical studies involving β-diketonated metal complexes have shown that a photon dissociates the chelate bond by excitation of π- transition and reduces their solubility in organic solvents or acid aqueous solutions due to the structural changes associated with the photodecomposition of chelate rings. Thus, the direct photoinscription of inorganic sol-gel materials is possible via the photochemical feature of β-diketone in sol-gel matrix. This method has been used to fabricate micropatterning, gratings, and planar waveguides. The chelated metal complex can be incorporated with inorganic-organic hybrid materials to fabricate micropatterning of thick hybrid gel films. In this study, we investigate the photochemical properties of gel films fabricated using GPTS as a precursor for hybrid materials and chelated metal alkoxides, , , , as a refractive index modifier as well as photobleaching agent. GPTS with various metal - Ti, Zr, Al, chelated with β-diketone (BzAc) or...한국과학기술원 : 재료공학과
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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