Microwave plasma enhanced chemical vapour deposition (MPECVD) was used for the production of carbon nanotubes. Vertically aligned multi-walled carbon nanotubes (MWCNTs) were grown on silicon substrates coated with cobalt thin films of thickness ranging from 0.5 nm to 3 nm. Prior to the nanotube growth the catalyst were treated with N-2 plasma for 5-10 minutes that break the films into small nanoparticles which favour the growth of nanotubes. The CNTs were grown at a substrate temperature of 700 degrees C for 5, 10 and 15 minutes. The height of the CNT films ranging from 10 mu m-30 mu m indicating that the initial growth rate of the CNTs are very high at a rate of approximately 100 nm/sec. Electrical resistivity of the above samples was evaluated from I-V measurements. The activation energy (E-a) was also calculated from the temperature dependent studies and it was found that the E-a lies in the range of 15-35 meV. Raman spectroscopy was used to identify the quality of the nanotubes.
Bibliographical note2nd International Meeting on Developments in Materials, Processes and Applications of Nanotechnology (MPA 2008), Cambridge, ENGLAND, JAN
- Carbon Nanotubes
- Electrical Properties
- Raman Spectroscopy