Carbon nanotubes grown by gas source molecular beam epitaxy

Carbon nanotubes have been grown by gas sourer molecular beam epitaxy with the presence of Ni catalyst. Some nanotubes show thinner bases compared wit h their heads. The influence of initial Ni layer thickness as well as growt h temperature on the nanotubes formation is studied. The growth of carbon n anotubes heavily depends on the size of the metal droplets and growth tempe rature. Raman spectra show graphite and glassy carbon structure for too thi ck and too thin initial Ni layer films, respectively. (C) 2001 Elsevier Sci ence B.V. All rights reserved.