Growth of carbon nanotubes on Si substrate using Fe catalyst produced by pulsed laser deposition

We report the growth of carbon nanotubes on the size controlled iron catalytic nanoparticles. The nanotubes were grown by thermal chemical vapour deposition (CVD) in the temperature range 600-850 degrees C. The Fe films were deposited on silicon by pulsed laser deposition in vacuum. Atomic force microscopy measurements were performed on the catalytic nanoparticles. The topography of the catalytic nanoparticles shows the homogenous distribution of Fe catalyst. We observe the nanotubes are produced only at temperatures between 650 and 800 degrees C, and within this narrow temperature regime the yield of nanotubes reaches a maximum around 750 degrees C and then declines. Raman measurements illustrate a high G/D peak ratio indicating good nanotube quality. By further defining the size of the catalyst the diameter of these carbon nanotubes can be controlled.