Growth of carbon nanostructure materials using laser vaporization

Carbon nanoparticles and nanotubes have been synthesized on Si substrates u sing pulsed laser vaporization. Two kinds of targets were used to grow the nanostructural materials. One was a pure carbon target and the other was ca rbon target containing Ni and Co catalysts, The growth temperatures were 60 0-1000 degreesC and the argon pressure was 500 torr. Samples were character ized by scanning electron microscopy, X-ray diffraction, and Raman spectros copy. Materials containing carbon nanocrystal particles could be observed u sing a pure carbon target when a thin Ni film was deposited on (100) Si sub strates prior to growing carbon materials. The carbon nanotubes (CNT) were obtained in carbon soot when the target contained catalysts. By comparing t he Raman radial breathing modes of the CNT grown at various temperatures, i t was found that the density of the CNT was lower and the strongest Raman p eak was slightly blue-shifted in samples grown at lower temperatures. (C) 2 001 Elsevier Science B,V, Ah rights reserved.