Diamond is an excellent engineering material. Our main interest in CVD diamond film deposition is understand the nucleation mechanism. Through better understanding of the physics, we hope to fabricate better and smoother thin film over large area. One technique we developed in 1992 was to use a two-step process to deposit (100) oriented diamond thin film on silicon substrate. This research resulted in one publication in Journal of Material Research Vol. 7, 1606 (1992) and one US Patent. (5,240,749). Another technique we developed in 1995 was to use a Hot filament technique to bombard graphite with energetic electrons to convert graphite into diamond thin film under pure hydrogen atmosphere. The result of this research was published in Solid State Communications, 93, 999, (1995).
Using the hot filament chemical vapor deposition (CVD) method, we showed that Fullerenes (Both C60 and C70) can be produced. The fullerenes occur in the soot that forms as a by-product of diamond deposition. The result was published in Appl. Phys. Lett., 66, 430 (1995). A US patent (5,510,098) was granted for the method to produce and doping of fullerene using CVD method. Later we also showed that microwave enhanced CVD of acetylene and hydrogen mixture can also produce fullerenes. This resut was published in "High Temperature Synthesis of Materials" ed. by Michael Serio and R. Malhartra.
Our current activity is concentrated on carbon nanotubes. Both catalytic Chemical Vapor Deposition method and carbon arc method are been used to produce carbon nanotubes with diameter between 20 and 100 nm and length of a few micrometer. One of the most difficult task in nanotube research is handling of the nanotubes due to its size. We recently developed a technique to grow nanotubes with an outer layer of 1 - 5 microns in diameter. This way we can handle the nanotube with a tweezers under optical microscope. An image of nanotube with a shaft is shown here. For more information please contact me at lc@physics.ucf.edu. These carbon nanotubes can be used as tips for atomic force microscope. This work is in collaboration with Dr. Jeff Bindell of Lucent Technologies.
