A nanotransistor is a transistor - the component that acts as an electronic signal switch or amplifier - that is near the scale of a billionth of a meter (or nanometer ) in size. ( Nano is from the Greek nanos meaning dwarf.) Although there is currently no transistor of this scale in practical use, a number of approaches toward achieving such a remarkable component of Nanotechnology appear promising. In November, 2001, Bell Labs scientists announced their ability to create in a laboratory individually-addressable nanotransistors at the single molecule level. About 10 million of such nanotransistors would fit on the head of a pin.
In the Bell Labs experiment, the difficult challenge of attaching electrodes to each molecule was overcome by designing a chemical manufacturing process that essentially allows the electrode contacts to "self-assemble." The process, which is described as "elegant in its simplicity," does not require a clean room as conventional fabrication does. The new approach to a one-molecule transistor is described in detail in an article in Science magazine.
An earlier approach to a nanotransistor was described in late 1999 as a ballistic nanotransistor because the components of the transistor allowed current to flow without the usual 65% loss of today's transistors.