Electromechanical memory array using nanotube ribbons and method for making same

DETAILED DESCRIPTION Preferred embodiments of the invention provide new electromechanical memory arrays and methods for making same.
In particular, electromechanical memory cells are created that operate analogously to the NTWCM devices disclosed in WO 01/03208, which is hereby incorporated by reference in its entirety.
However, unlike the NTWCM devices disclosed in WO 01/03208, preferred embodiments of the invention replace the suspended nanoscopic wires used in the NTWCM devices with new ribbons made from a matted layer of nanotubes or a non-woven fabric of nanotubes.
These new devices are referred to herein as nanotube ribbon crossbar memories (NTRCMs).
The new nanotube belt structures are believed to be easier to build at the desired levels of integration and scale (in number of devices made) and the geometries are more easily controlled.
Because the new nanotube belt crossbar memory devices operate analogously to NTWCM, the description of their architecture and principles of operation is brief.
Reference may be made to WO 01/03208 for fuller description and background.
FIG.
1 illustrates an exemplary electromechanical memory array 100 constructed according to principles of preferred embodiments of the invention.
The array has a plurality of non volatile memory cells 103 which can be in an "on" state 105 or "off" state 106.
The actual number of such cells is immaterial to understanding the invention but the technology may support devices having information storage capacities equivalent to or larger than modern non-volatile circuit devices.
Each memory cell 103 includes a nanotube ribbon 101 suspended by one or more supports 102 over electrical traces or wires, e.
g.
, 104.
Each crossing of a ribbon 101 and a wire, e.
g.
, 104 forms a crossbar junction and defines a memory cell.
Under certain embodiments, each cell may be read or written by applying currents and or voltages to electrodes 112 which are in electrical communication with ribbons 101 or through electrodes (not shown) in communication with traces or wires 104