Abstract Submitted to the    NANOTUBE'04 Conference:

In order to fabricate vertically-aligned-high-quality carbon nanotubes (CNT) at a low-temperature below glass transition point by CVD process, preheating of the reaction gas, carbonization of the catalysts and selection of the binary catalysts, have been investigated. It is found that (1) The preheating at 700 ^oC enhances the reactivity of a carbon source gas of acetylene and contributed to the decomposition of the gas in high efficiency on the surfaces of the catalysts heated at 550 ^oC; (2) The catalyst of iron is activated by the carbonization using a mixture of a carbon source gas and an inert gas at a temperature below 500 ^oC; (3) For the selection of binary catalysts, Al/Fe and Co/Ti were used. It has been confirmed that using Al, which has a low melting point, as a grounding film facilitates Fe-particle formation at low temperature and also prevents the Fe particles from aggregation. Co/Ti animates Co catalyst to grow aligned CNTs at a low temperature even without the carb onization process. This is because Co is difficult to intermingle with Ti and hold high reactivity. It is evidenced that the three kinds of techniques are very effective in the CNT growth at a low temperature of 550 ^oC.