AVS1999 Session NT+NS+EM+MS-WeP: Poster Session
Wednesday, October 27, 1999 5:30 PM in Room 4C
Wednesday Afternoon
Time Period WeP Sessions | Topic NT Sessions | Time Periods | Topics | AVS1999 Schedule
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NT+NS+EM+MS-WeP-1 Growth of Carbon Nanotubes at Low Temperature by Microwave Plasma-enhanced Chemical Vapor Deposition
Y.C. Choi, D.J. Bae, Y.H. Lee, B.S. Lee (Jeonbuk National University, Korea) We have grown carbon nanotubes at temperatures below 520 C by microwave plasma-enhanced chemical vapor deposition using methane and hydrogen gases. Carbon nanotubes were uniformly grown in large area of transition metal-coated Si substrates with high density. Each nanotube is terminated by transition metal cap, suggesting that the transition metals play an important role in the nanotube growth. Carbon nanotubes are curly in all cases, indicating the nanotubes to be defective due to very low growth temperature. Diameters and lengths of the nanotubes could be controlled by changing the ratio of methane to hydrogen and growth time. Raman spectum clearly shows the peak at 1592 cm-1 (G-band), indicating the formation of well graphitized carbon nanotubes. |
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NT+NS+EM+MS-WeP-2 Nanoscale-controlled Handling of Carbon Nanotubes
O. Jaschinski, P. Bernier, L. Vaccarini, C. Goze (Universite Montpellier II, France); G. Duesberg (Trinity College Dublin, Ireland); C. Journet, S. Roth (Max-Planck-Institut fuer Festkoerperforschung Stuttgart, Germany) Carbon nanotubes are the most promising materials for applications in nanoelectronics and nanomechanics. For the determination of the electrical and mechanical properties of nanotubes and for the production of nanotube devices one needs the ability to handle nanoscale materials in a controlled way . We demonstrate how atomic force microscopy (AFM) can be used as a tool for manipulating and investigating carbon nanotubes. For an optimal use of AFM it is necessary to control the substrate-nanotube interaction. We present results of measurements of the mechanical properties of nanotubes obtained with various kinds of substrates. We show how the combination of lithography, manipulation by AFM and control of the adsorption process of nanotubes allow to prepare well defined sample configurations for very sophisticated measurements of the electrical and mechanical properties of carbon nanotubes. Based on these methods, techniques for the production of nanotube devices can be developed. This work was supported by European TMR contract NAMITECH ERBFMRX-CT96-0067 (DG12-MIHT) |
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NT+NS+EM+MS-WeP-3 Aligned Carbon Nanotubes with Controlled Diameters Using Anodic Alumina Template
S.-H. Tsai, H.C. Shih (National Tsing Hua University, R.O.C.) The microwave plasma enhanced chemical vapor deposition (MPECVD) system had been successfully fabricated the well-controlled diameters of aligned carbon nanotubes on the anodic alumina template with a mixture of methane and hydrogen. Prier to test, the anodic alumina with pore arrays in various diameters were prepared by anodizing aluminum using oxalic, sulfuric, and phosphoric acid solutions. By adjusting the pore size of the anodic alumina, various carbon nanotube diameters can be obtained in a range of 30 to 100 nm and were examined by scanning electron microscopy and transmission electron microscopy. |
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NT+NS+EM+MS-WeP-4 The Selective Growth of Aligned Carbon Nanotubes by PECVD Using Nickel Catalyst
H. Jeon, K. Ryu, M. Kang (Hanyang University, Korea) Carbon nanotubes have been studied extensively because of their own unique physical properties and also of their application potential for field emitters. One of the interesting applications is reported for display application, but neither industrial fabrication technology nor performance has been reported for practical display application. Here we tried to grow aligned carbon nanotubes selectively by plasma enhanced chemical vapor deposition (PECVD) method using nickel catalyst1 at temperatures below 600°C. These conditions for low temperature growths are suitable for field emission display which requires carbon nanotube emitters grown perpendicular to the Si substrate. In our experiment, a thin film of nickel(10-100nm) was deposited through a pattern mask on a Si substrate in UHV e-beam evaporator and was agglomerated by in-situ annealing for thirty minutes at 700°C. The use of a patterned catalyst enhanced the formation of selectively aligned nanotubes at low temperatures. After this process, Ni particles deposited on Si substrate were examined by AFM and SEM. Carbon nanotubes were selectively grown on Ni particle by PECVD with using the mixture of CH4 and NH3 at 600°C. In this process, CH4 was used as the carbon source and NH3 was used as a catalyst and dilution gas. During the process, many carboneous impurities can be produced and tried to eliminated by introducing H2 plasmas. We examined the physical properties of carbon nanotubes by SEM, XRD and Raman spectroscopy. And we investigated the formation temperature of carbon nanotubes on silicon substrate and controlled the selective growth of aligned nanotubes. |