Advanced nanosphere lithography for the areal-density variation of periodic arrays of vertically aligned carbon nanofibers

Periodic arrays of vertically aligned isolated carbon nanofibers (CNFs) have been fabricated using self-assembled polystyrene spheres as shadow masks for catalyst-pattern formation. Proper use of monolayer and bilayer masks, and judicial combination of angle-deposition technique with monolayer masks have allowed us to control the dot size and spacing of catalyst patterns. As long as the catalyst-dot size is not too large, isolated single CNF has grown from each catalyst dot. Combining nanosphere lithography with conventional photolithography, we have been able to realize patterned growth of CNF arrays on selected areas.