CONTACT METALLIZATION OF CARBON NANOTUBES
In one embodiment, SWNTs are synthesized from an embedded catalyst in a modified porous anodic alumina (PAA) template. Pd is electrodeposited into the template to form nanowires that grow from an underlying conductive layer beneath the PAA and extend to the initiation sites of the SWNTs within each pore. Individual vertical channels of SWNTs are created, each with a vertical Pd nanowire back contact. Further Pd deposition results in annular Pd nanoparticles that form on portions of SWNTs extending onto the PAA surface. Two-terminal electrical characteristics produce linear I-V relationships, indicating ohmic contact in the devices.
1 . A method of producing a nanoporous array, comprising:
providing a film of aluminum;
imprinting a pattern of sites on the surface of aluminum;
creating a pattern of defects corresponding to the pattern of sites;
anodizing the aluminum with the pattern of defects; and
creating a pore from each defect by said anodizing.
2 . The method of claim 1 wherein the sites have a characteristic size less than about twenty nanometers and the spacing between adjacent sites are less than about one hundred nanometers.
3 . The method of claim 1 which further comprises creating a pattern of voids in the layer by developing the exposed resist material.
4 . The method of claim 1 wherein said providing a film includes fabricating a template of first and second layers of aluminum separated by a catalytic layer.
5 . The method of claim 4 wherein at least a portion of one outer surface of a layer of aluminum has an electrically conductive material deposited thereon.
6 . The method of claim 5 which further comprises synthesizing at least one carbon nanotube from the catalytic layer in the pore.
7 . The method of claim 4 wherein said fabricating includes a third layer of aluminum separated from the second layer of aluminum by a second catalytic layer.
8 . The method of claim 7 which further comprises synthesizing a second carbon nanotube in the pore from the second catalytic layer.
9 . The method of claim 5 which further comprises synthesizing at least one carbon nanotube in each pore.
10 . The method of claim 9 which further comprises electrodepositing a quantity of metal in each of the plurality of pores sufficient to establish electrical contact from the nanotube to a layer of conductive material.
11 . The method of claim 9 which further comprises electrodepositing a nanoparticle of metal on an end of at least one of the nanotubes.