Carbon nanotubes are known as elongated tubular bodies which are typically only a few atoms in circumference. Methods of forming carbon nanotubes are described, for example, in U.S. Pat. Nos. 5,753,088 and 5,482,601. The nanotubes are hollow and have a linear fullerene structure. Advantageously, the length of the nanotubes potentially may be millions of times greater than the molecular-sized diameter. Carbon nanotubes are currently being proposed for a number of applications since they possess a very desirable and unique combination of physical properties relating to, for example, strength and weight. The nanotubes have also demonstrated electrical conductivity. See Yakobson, B. I., et al., American Scientist, 85, (1997), 324-337; and Dresselhaus, M. S., et al., Science of Fullerenes and Carbon Nanotubes, 1996, San Diego: Academic Press, pp. 902-905. Investigative efforts regarding nanotubes have primarily focused on theoretical attempts to evaluate the nanotube molecular structure, and its potential relationship to physical properties.
Notwithstanding these efforts, there remains a need in art for a method to alter the physical properties of a nanotube such that it may be modified for various end use applications. For example, it would be particularly desirable to be able to alter the electrical properties within the nanotube such that the nanotube exhibits heterogeneous electrical behavior. As a result, the nanotube may be useful in microelectronic device applications which often demand high thermal conductivity, small dimensions, and light weight.