US Patent 7253434 - Suspended CNTFET

http://www.freepatentsonline.com/7253434.html

Carbon nanotube FETs have been proposed in a variety of configurations including structures where the nanotube is used as a vertical structure for gate control and wherein a plurality of nanotubes are aligned over a source/drain connection for gate control. This patent from Harvard proposes a suspended nanotube structure to form the CNTFET. Claim 1 reads:

1. A carbon nanotube field effect transistor comprising: a carbon nanotube having a length suspended between a source electrode and a drain electrode that are together disposed on a common surface of a support structure; a gate dielectric material coaxially coating the suspended nanotube length and coating at least a portion of the source and drain electrodes; and a gate metal layer coaxially coating the gate dielectric material along the suspended nanotube length and overlapping a portion of the source and drain electrodes, separated from the electrodes by the gate dielectric material.

US Patent 7253431 - Carbon nanotube doping using one electron oxidant

http://www.freepatentsonline.com/7253431.html

Depending on their chirality single walled nanotubes have intrinsic semiconductor properties however extrinsic doping using O2, NO2, Br2, and I2 (electron acceptors) and K, Cs, NH3 (electron donors) have also been reported in the literature. This patent from IBM teaches using what they refer to as "one-electron oxidants" which is taught in the specification to include itrialkyloxonium hexachlroantimonate, antimony pentachloride, nitrosonium salts, tris-(pentafluorophenyl) borane or nitrosonium cation to provide more reliable preparation of extrinsically doped nanotubes for FETs. Claim 1 reads:

1. A method for doping a carbon nanotube comprising: exposing the carbon nanotube to a one-electron oxidant in a solution, such that one electron is transferred from the carbon nanotube to each molecule of the one-electron oxidant.

US Patent 7247877 - Integrated circuit monitor using CNTFET

http://www.freepatentsonline.com/7247877.html

Several integrated circuit designs include monitoring circuits built into the chip to assure proper functioning of the circuit. However, the space taken up by these circuits can increase the size of the chips and reduce overall performance. This patent from IBM teaches the use of carbon nanotube field effect transistors to detect defective transistors with a greater economy of space.

1. An integrated circuit comprising: a primary transistor device to be monitored; and an embedded carbon nanotube field effect transistor (CNT FET) spaced apart from said primary transistor device to be monitored, wherein said CNT FET is adapted to detect defective circuits and measure physical characteristics within said integrated circuit, wherein said CNT FET is adapted to measure any of mechanical and thermal stress and strain in said integrated circuit, and wherein said primary transistor device to be monitored comprises: a gate; a source region; a drain region; and a gate insulator layer separating said gate from each of said source region and said drain region.