Browsing by Author "Chang, Hui Lin"

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Formation of Bamboo-Like Carbon Nanotubes and Nanofibers Using Co-Si-O and Co-Si Catalysts
(2010)
Chang, Hui Lin
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Kuo, Cheng Tzu
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材料科學與工程學系
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Department of Materials Science and Engineering
Bamboo-like carbon nanotubes were synthesized by microwave plasma chemical vapor deposition (MPCVD) using CH(4) and N(2) as source gases in various ratios. Two types of catalytic films, namely, a condition 1, Co film/SiO(2)/Si substrate, and, a Co film/Si substrate layer with rapid thermal annealing (RTA; condition 2), were used as catalysts to grow carbon nanotubes. The interaction between the catalytic film and the Si substrate or between the catalytic film and the SiO(2) interlayer occurred during the H(2) reduction step before nanotube growth. The chemical compositions of catalytic particles capping the carbon nanotubes were identified by energy-dispersive X-ray spectroscopy (EDS) as Co-Si-O and Co-Si for conditions 1 and 2, respectively. The growth of the base and tip growths was investigated and is suggested to be governed by the capillary effect and the strength of adhesion between the catalytic particles and the underlayer. Transmission electron microscopy (TEM) analysis reveals that the carbon nanotubes and nanofibers have bamboo-like structures with hollow internal compartments. The formation mechanisms of these bamboo-like structures are discussed. (C) 2010 The Japan Society of Applied Physics
Multi-Walled Carbon Nanotubes Growing Vertically from Root Particles
(2010)
Chang, Hui Lin
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Kuo, Cheng Tzu
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材料科學與工程學系
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Department of Materials Science and Engineering
The catalytic growth of multi-walled carbon nanotubes (MWCNTs) was performed on Si substrates with and without interfacial layers, by microwave plasma chemical vapor deposition (MPCVD). Many vertically grown, dense MWCNTs attached to a catalytic film penetrated the root particles. The diameter of root particles, in the order of 100 nm, is larger than the tube diameters of 10-15 nm. Base growth and tip growth are proposed as part of a new CNT growth model. The interaction between catalytic film and the supporting interfacial layer is suggested to determine whether the catalytic particles are driven up or pinned down on the substrate during the growth. (C) 2010 The Japan Society of Applied Physics
STRUCTURES AND PROPERTIES OF THE CRYSTALLINE Si-C-N USING ADDITIONAL Si-SOURCE AND Co-CATALYST
(2003-12-01)
Chang, Hui Lin
;
Fang, Jau Shiung
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Kuo, Cheng Tzu
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材料科學與工程學系
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Department of Materials Science and Engineering
Si-C-N films were synthesized on Si substrates by microwave plasma chemical vapor deposition (MPCVD) with a mixture of CH4 and N-2 as gaseous sources, and Co-coated Si columns to act as a catalyst and an additional Si source. Two conditions, conditions 1 and 2, were implemented by varying the time at which the solid sources were introduced. Under condition 1, the solid sources were applied \'before\' film deposition. Under condition 2, the solid sources were applied both \'before and during\' film depositions. Analytical results indicate, although that both conditions yield crystalline Si-C-N films, the time at which the solid sources are applied is critically affects the films\' structures and properties. Synthesizing Si-C-N films under condition 1 yields crystals with more re-nucleation, a structure closer to a pseudo T-Si3N4 structure, a higher C content, detectable Si(2p)-C bonding, lower nano-hardness and better field emission properties. Synthesis of film under condition 2 yields, crystals with more facets, a structure closer to pseudo alpha-Si3N4 and an additional thin layer under the crystalline layer. SEM, TEM, XPS, XRD, nanoindentor and field emission were used to characterize the film\' structures and properties.
Synthesis and Characterization of Silicon and Nitrogen Containing Carbon-Based Crystals and Their Nanostructured Materials
(2014)
Chang, Hui Lin
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Chang, Chi Tso
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Kuo, Cheng Tzu
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交大名義發表
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材料科學與工程學系
The synthesis of carbon-based materials, such as man-made diamonds, superhard C3N4 materials, SiCN crystals, and other carbon-based nanostructured materials, has attracted considerable attention for many decades in academic and industrial communities. However, so far, researchers have not successfully linked the growth mechanisms of carbon-based materials deposited under different synthetic conditions and methods. In fact, a single machine may produce many of these materials. This paper is aimed to study the linkages among various carbon-based materials synthesized on Si wafers using the same microwave plasma chemical vapor deposition system, including SiCN crystalline films, SiCN nanotubes, carbon nanotubes (CNTs), conical carbon nanorods, and other nanostructured materials. (C) The Author(s) 2014. Published by ECS. All rights reserved.