Abstract: Carbon nanotube (CNT) films were prepared on nickel foil substrates by low pressure chemical vapor deposition (LPCVD) with acetylene and hydrogen as the precursors. The effect of acetylene
flow rate on the morphology and structure of CNT films was investigated. The morphology and structure of CNTs depending on the acetylene flow rate
were characterized by scanning electron microscope, transmission electron microscope and Raman spectroscope, respectively. With increasing the acetylene
flow rate from 10 to 90sccm, the growth rate of CNT films increases and the thickness increases from 400 to 1000\mum, while the diameter of the CNTs
increases from 10 to 300nm. Also, the defects and amorphous phase in the CNT films increase with increasing the acetylene flow rate.

Key words: carbon nanotubes, chemical vapor deposition, SEM, TEM, Raman spectra