Tuesday, December 09, 2008

US Patent 7462499 - ZnO coated CNTs for field emission


Due to the high aspect ratio and electrical properties of carbon nanotubes they have exceptional electron emission behavior useful to flat panel displays and electron beam lithography. This patent from Sharp teaches further improvement in the emission by forming ZnO material regions extending from the carbon nanotube tips. Claim 1 reads:

1. A method for fabricating a nanotube with ZnO asperities, the method comprising:

forming a substrate;

growing carbon nanotubes (CNTs), with a surface, from the substrate;

conformally coating the CNTs with ZnO;

annealing the ZnO-coated CNTs; and,

forming ZnO asperities on the surface of the CNTs in response to the annealing.