Wednesday, April 15, 2009

US Patent 7517558 - Mask structure for CNT patterning

This patent from Micron Technology teaches a deposition system for accurately placing carbon nanotubes in desired patterns and counting the number of nanotubes that are deposited. Claim 1 reads:

1. A method of positioning carbon nanotubes, comprising:

creating a dusty plasma comprising a plurality of carbon nanotubes;

positioning a mask between said dusty plasma and a desired target for said carbon nanotubes, said mask having a plurality of openings extending therethrough;

extinguishing said dusty plasma;

the carbon nanotubes falling out of the extinguished plasma and toward said mask, the mask patterning the falling carbon nanotubes to form a pattern of the carbon nanotubes on said target;

wherein said plurality of openings correspond to a plurality of funnels;

wherein each of said funnels comprises an inlet and an outlet, with the outlet being narrower than the inlet along at least one cross-section; and

using parallel spaced-apart conductive plates to count nanotubes exiting the outlets of the funnels.