Carbon nanotube transistor having low fringe capacitance and low channel resistance

A carbon nanotube (CNT) transistor, comprising:

• a) a conductive source electrode (source) disposed on a substrate;
• b) a conductive drain electrode (drain) disposed on a substrate;
• c) a semiconducting CNT having a variable resistance electrically connected between the source and the drain;
• d) a conductive gate electrode (gate) disposed proximate to the semiconducting CNT, for controlling the resistance thereof, wherein:
• 1) a first gap exists between the gate and source,
• 2) a second gap exists between the gate and drain,
• wherein the semiconducting CNT spans the first and second gaps;
• and
• the CNT transistor includes at least one of the following extensions:
• e) a conductive source extension extending from the source into the first gap;
• f) a conductive drain extension extending from the drain into the second gap;
• wherein the extensions comprise metallic-conducting carbon nanotubes surrounding and coaxial with the semiconducting CNT.

A carbon nanotube (CNT) transistor, comprising:

• a) a semiconducting CNT electrically connected between a source electrode and a drain electrode;
• b) a gate electrode disposed proximate to the semiconducting CNT, for affecting the resistance thereof, wherein the gate electrode is separated from the source and drain electrodes by first and second gaps, respectively;
• c) a conductive source extension extending from the source into the first gap;
• d) a conductive drain extension extending from the drain into the second gap;
• wherein the extensions comprise metallic-conducting carbon nanotubes surrounding and coaxial with the semiconducting CNT.