AVS 51st International Symposium
    Nanometer-scale Science and Technology Tuesday Sessions
       Session NS-TuM

Paper NS-TuM3
Low-temperature Synthesis of Aligned Carbon Nanotubes by Hot-Filament Assisted DC Plasma CVD

Tuesday, November 16, 2004, 9:00 am, Room 213D

Session: Nanotube Processing and Composite Materials
Presenter: Y. Watanabe, Kyoto Institute of Technology, Japan
Authors: Y. Watanabe, Kyoto Institute of Technology, Japan
Y. Hayashi, Kyoto Institute of Technology, Japan
S. Nishino, Kyoto Institute of Technology, Japan
Correspondent: Click to Email
Carbon nanotubes (CNTs) are expected to be used for the field emitters of field emission display (FED) because their high aspect ratio and small radius of curvature lead to large electric-field enhancement at their tips resulting in low operating voltage for electron emission. The synthesis method of vertically aligned CNTs in low temperature below the softening point of a glass substrate should be developed to apply CNTs to field emitters of FED. Motivated by such a background, we carried out experiments of synthesis of CNTs in low temperature by hot-filament assisted DC plasma chemical vapor deposition (HF/DC-PCVD)@super 1@. The growth method and conditions were as follow. First a Co foil substrate was heated by hot tungsten filaments in H@sub 2@ atmosphere. Then after 10 min pretreatment in a H@sub 2@ plasma, CH@sub 4@ gas was added for the growth of nanotubes. DC voltage of -450V was applied to the substrate with the hot-filaments grounded. During the growth, substrate temperature was controlled about 500°c, the gas pressure was 20Torr, and growth time was 10 min. Well-aligned CNTs about 60 nm in diameter were observed by scanning electron microscopy in the density of about 10@super 9@ cm@super -2@ on the surface of the substrate. We have succeeded to synthesize well-aligned and high density carbon nanotubes on Co substrate at 500°c. @super 1@Y.Hayashi, T.Negishi, and S.Nishino, J. Vac. Sci. Technol. A 19(2001) 1796.