US Patent 7095645 - Nanobeam Memory

http://www.freepatentsonline.com/7095645.pdf

The use of nanotubes to form mechanical memory devices has been developed primarily using ribbons of nanotube by a company named Nantero. This patent from Ambient Systems takes a slightly different approach. It uses individual nanotubes in a cantilever configuration to form a nanobeam. A series of control electrodes surround the nanotube and are maintained at balancing potentials that keeps the nanotube at a central equilibrium position. Removing or altering potential from one of the electrodes eliminates the equilibrium state and creates a specific memory state in which the nanotube moves to one of a plurality of sensing positions. With this configurations two, three, or more memory states (depending on the number of balancing electrodes) can be stored per nanotube. Claim 1 reads:

1. A nanometer-scale memory cell comprising: a base; a mounting assembly attached to said base; a nanometer-scale beam fixed to said mounting assembly and having a first portion that is free-to-move; and a first charge containment layer isolated by non-conductive layers and coupled to said base in the proximity of said first free-moving portion, being able to store a first charge profile in said charge containment layer without moving said nanometer-scale beam.