Patent ID: 8106382

Claim:
A field-effect transistor comprising: a substrate; a plurality of semiconductor nanostructures supported by the substrate; a source electrode connected to a portion of at least one semiconductor nanostructure among the plurality of semiconductor nanostructures; a drain electrode connected to another portion of the at least one semiconductor nanostructure; an insulating film adjoining the at least one semiconductor nanostructure and functioning as a gate insulating film; and a gate electrode being capable of controlling electrical conduction of the at least one semiconductor nanostructure via the insulating film, wherein, each of the plurality of semiconductor nanostructures includes a low concentration region having a relatively low doping concentration and a pair of high concentration regions having a higher doping concentration than that of the low concentration region and being connected to both ends of the low concentration region; the doping concentration of the high concentration region is 1×10 19 cm −3 or more; and a length of the low concentration region is shorter than a length of the gate electrode along a direction from the source electrode to the drain electrode, and the length of the gate electrode is shorter than an interspace between the source electrode and the drain electrode, wherein the length of the semiconductor nanostructures is longer than an interspace between the source electrode and the drain electrode.