Carbon Nanotube Transistor

If a 2-D sheet of graphene is rolled, the resulting 1-D structure is known as a carbon nanotube. (Figure 3436 (b)) The reason to treat it as 1-dimensional is that it is highly conductive. Electrons traverse the carbon nanotube with being scattered by a crystal lattice. Resistance in normal metals is caused by scattering of electrons by the metallic crystalline lattice. If electrons avoid this scattering, conduction is said to be by ballistic transport. Both metallic (acting) and semiconducting carbon nanotubes have been produced.

Field effect transistors may be fashioned from a carbon nanotubes by depositing source and drain contacts on the ends, and capacitively coupling a gate to the nanotube between the contacts. Both p- and n-type transistors have been fabricated. Why the interest in carbon nanotube transistors? Nanotube semiconductors are Smaller, faster, lower power compared with silicon transistors.