Gas-surface kinetics modeling for carbon nanotube deposition
Abstract
The role of the interaction between the gas and transition metal catalyzed substrates in the chemical vapor deposition (CVD) of carbon nanotubes (CNT) is of considerable interest. To be able to use computational tools to predict the growth of CNTs and thus optimize process parameters and catalyst recipes, this interaction must be modeled. To this end, a computational fluid dynamics model of a dc plasma enhanced CVD reactor is extended to include a surface chemistry model. The fluid model solves a set of partial differential equations for gas phase species mass, gas temperature, plasma temperature and plasma potential. For the surface, chemical kinetic rate expressions are used for the chemisorption and subsequent dehydrogenation of gas phase hydrocarbons as well as carbon diffusion through the catalyst. The expressions for the conservation of mass at the surface form a set of ordinary differential equations that are time-integrated and coupled to the gas model to provide CNT growth rates.
- Publication:
-
APS Annual Gaseous Electronics Meeting Abstracts
- Pub Date:
- October 2003
- Bibcode:
- 2003APS..GECCT1005H