| This thesis proposes several novel fabrication methods for Nanoimprint molds to fabricate complex micro/nano-structures and shows some applications of Nanoimprint Lithography (NIL) in electronics and optics. Mold fabrication methods are one of the key issues of Nanoimprint Lithography, one of the next generation lithography technology that has demonstrated great capability for the fabrication of large-area planar periodic structures. By combining interference lithography, edge lithography and self-alignment by shadow evaporation, NIL molds for large-area (wafer scale) nano-split-ring arrays can be fabricated. By applying special techniques some quasi-three-dimensional structures can be fabricated by NIL. For example, large-area microlens arrays can be duplicated with molds that fabricated by applying resist reflow and dispensing imprint. By conformal deposition and selective etching an imprint mold for the smallest T-shaped gates mark to date (16 nm foot-width) was achieved. With the equipment of novelly fabricated molds and the state-of-the-art NIL technology in our lab, the application of NIL in optics and electronics is investigated. The theoretical analysis, fabrication and evaluation of nano-wire tunneling FETs made by NIL are presented in this thesis. Finally, a new alignment method that uses two overlaid subwavelength resonant gratings is proposed and studied. This method can simultaneously achieve wafer leveling and translational alignment. |
