Tuesday, February 05, 2008

US Patent 7326328 - Nanorod field emitter formed in AAO template


This patent from GE discloses a method for making a nanorod field emitter array using an AAO template formed in a mesa structure (note: nanorods are typically larger diameter nanowires with smaller aspect ratios). The method produces a smaller emitter to gate distance for more efficient emission. Claim 1 reads:

1. A method comprising the steps of:
a) providing a thin film material comprising: i) a substrate; ii) a dielectric layer on the substrate; and iii) a conductive film on the dielectric layer;
b) lithographically-patterning a patternable material deposited onto the conductive film so as to selectively remove portions of this material;
c) selectively etching the conductive film and dielectric layer in regions where the patternable material has been removed so as to form microcavities;
d) depositing Al inside the microcavities to form Al mesas;
e) anodizing the Al mesas to form localized nanoporous AAO templates; and
f) electrochemically-depositing nanorods in the nanopores of the AAO templates to yield at least one gated nanorod field emission device.