US Patent 8147791 - Reduction of graphene oxide to graphene

http://www.freepatentsonline.com/8147791.html

This patent from Northrop Grumman Corp. teaches a new way to manufacture graphene material based on the oxidation of graphite followed by a reduction process. Claim 1 reads:

1. A method of creating graphene consisting of the steps of:

dispersing graphene oxide into water to form a dispersion;

adding a solvent to the dispersion to form a solution; and

controlling a temperature of the solution to form graphene.

US Patent 7579618 - Carbon nanotube resonator transistor

http://www.freepatentsonline.com/7579618.html

This patent from Northrop Grumman teaches a mechanically resonant carbon nanotube transistor providing a low output impedance in comparison to other CNT designs and a high operating frequency suitable for signal processing applications. Claim 1 reads:

1. A resonant transistor comprising:

a substrate;

a source formed on said substrate;

a drain formed on said substrate adjacent to said source,

a gap being formed between said source and said drain;

an input electrode formed on said substrate; and

a carbon nanotube gate positioned over said gap and over said input electrode, said nanotube gate being clamped on one end by a contact electrode.

US Patent 7359694 - CNT RF mixer

http://www.freepatentsonline.com/7359694.html

This patent from Northrop Grumman Corporation teaches forming pn diodes using carbon nanotubes and arranging these nanotube diodes in a quad configuration commonly seen in full wave rectifier circuitry. The benefit of the circuit is taught to be found in high frequency (>terahertz) mixers. Claim 1 reads:

1. A diode quad comprising:

a substrate;

first and second electrodes formed on the surface of said substrate and separated by a first gap;

fourth and third electrodes formed on the surface of the substrate and separated by a second gap, a portion of said fourth and said third electrodes being formed in said first gap;

a first p-n junction carbon nanotube diode connecting said first electrode with said third electrode;

a second p-n junction carbon nanotube diode connecting said first electrode with said fourth electrode;

a third p-n junction carbon nanotube diode connecting said second electrode with said third electrode; and

a fourth p-n junction carbon nanotube diode connecting said second electrode with said fourth electrode.