AVS 49th International Symposium
    Plasma Science Wednesday Sessions
       Session PS+NT-WeM

Paper PS+NT-WeM6
Carbon Nanotubes by ICP-CVD: Growth, Characterization, Plasma Diagnostics, and Modeling

Wednesday, November 6, 2002, 10:00 am, Room C-103

Session: Plasma Science and Technology for Nanostructures
Presenter: D.B. Hash, NASA Ames Research Center
Authors: D.B. Hash, NASA Ames Research Center
L. Delzeit, NASA Ames Research Center
K. Matthews, NASA Ames Research Center
B.A. Cruden, Eloret Corporation
M. Meyyappan, NASA Ames Research Center
Correspondent: Click to Email

Applications in field emitter devices, electrode and sensor development require a very high degree of vertical orientation of carbon nanotubes (CNTs) on the substrate. This is not possible using thermal CVD. The inherent electric field in a direction normal to the substrate in a plasma process enables achievement of vertical orientation of the nanotubes. We have built an ICP reactor and grown multiwalled carbon nanotubes (MWNTs) from hydrocarbon feedstock (CH@sub 4@, C@sub 2@H@sub 2@, and C@sub 2@H@sub 4@) diluted with hydrogen. The MWNTs have been characterized using SEM, HRTEM, and Raman scattering. The MWNTs are highly aligned and suitable for the applications mentioned above. Results as a function of pressure, substrate power, and temperature will be discussed. To understand the effects of process parameters on growth as well as mechanisms - including identification of species responsible for nanotube growth, we have undertaken a 2-D plasma modeling of the process. Modeling results are compared with plasma diagnostics using optical emission spectroscopy, UV Absorption, and Residual Gas Analysis (RGA).