K. Eric Drexler has written extensively about the design, performance and path of development of this system since 1981, when he published this untried concept. He defines molecular nanotechnology as the construction of objects to complex, atomic specifications using sequences of chemical reactions directed by nonbiological molecular machinery. Molecular nanotechnology describes the field, as a whole, comprising molecular manufacturing together with its techniques, its products, and their design and analysis. This new field is relative to, yet distinct from, mechanical engineering, microtechnology, chemistry, and molecular biology. As physics is related to engineering, so chemistry is related to molecular engineering.
Molecular manufacturing applies the principles of mechanical engineering to chemistry.
Figure 9-65 provides an example of the progress in molecular manufacturing. Nanotubes are formed by vaporized carbon that condenses into a series of hexagons. These hexagons naturally curl into hollow tubes. If the carbon sheet forming a nanotube is rolled up evenly, then the carbon molecules conduct electricity as if the sheet wee a metallic substance. Further, if the nanotubes are joined together end to end, then, their junction function acts as an electronic diode.