Dennis M. Callahan Jr.1, Katherine S. Ziemer2, Demetrios Papageorgiou3, Jonathan G. Leong4, Eko A. Pandowo4, and Al Sacco Jr.4. (1) Chemical Engineering, Center for Advanced Microgravity Materials Processing (CAMMP), Northeastern University, 250 Egan Research Center, 360 Huntington Avenue, Boston, MA 02115, (2) Chemical Engineering, Northeastern University, 360 Huntington Avenue, 148 Egan Research Center, Boston, MA 02115, (3) Electrical and Computer Engineering, Northeastern University, 333 Dana Research Center, 360 Huntington Ave, Boston, MA 02115, (4) Department of Chemical Engineering, Center for Advanced Microgravity Materials Processing (CAMMP), Northeastern University, 250 Egan Research Center, 360 Huntington Ave, Boston, MA 02115
Chemical vapor deposition (CVD) over transition metal catalysts has great potential for fabrication of nanotube-based electronic devices because the CVD method is easily controlled, scalable and, combined with standard lithographic techniques, allows for easy manipulation of the size and placement of catalyst particles. Thin films of nickel (Ni) were deposited on a fused quartz plate by thermal evaporation and subsequently reduced in 20 cc/s (STP) of hydrogen at 1173 K. This produced well-formed Ni nanoparticles with diameters ranging from ~6-11 nm, dependent of the amount of evaporated Ni. For carbon deposition, the temperature was reduced to 900 K and the environment switched to a gas mixture of H
2, CH
4, CO, CO
2 and H
2O. Carbon nanotubes and carbon filaments were grown and subsequently analyzed with a scanning electron microscope (SEM). Preliminary results suggest that selectivity of the carbon morphology is dependent on the catalyst particle size distribution as reported by Bazzana (1).
1.Bazzana, S. Ph.D. Thesis, Northeastern University, Boston (2004)