Imprinting of supported and free-standing 3-D micro- or nano-structures
View Patent ↗The present invention is directed to micro- and nano-scale imprinting methods and the use of such methods to fabricate supported and/or free-standing 3-D micro- and/or nano-structures of polymeric, ceramic, and/or metallic materials. In some embodiments, a duo-mold approach is employed in the fabrication of these structures. In such methods, surface treatments are employed to impart differential surface energies to different molds and/or different parts of the mold(s). Such surface treatments permit the formation of three-dimensional (3-D) structures through imprinting and the transfer of such structures to a substrate. In some or other embodiments, such surface treatments and variation in glass transition temperature of the polymers used can facilitate separation of the 3-D structures from the molds to form free-standing micro- and/or nano-structures individually and/or in a film. In some or other embodiments, a “latch-on” assembly technique is utilized to form supported and/or free-standing stacked micro- and/or nano-structures that enable the assembly of polymers without a glass transition temperature and eliminate the heating required to assemble thermoplastic polymers.
1. A method for assembling 3-D polymeric structures, wherein such 3-D polymeric structures are structured such that they comprise features with dimensions that range from the nano-scale to the micro-scale, comprising the steps of:
a) providing a first 3-D polymeric structure on a substrate;
b) providing a second 3-D polymeric structure in a surface-treated mold;
c) pressing the second 3-D polymeric structure into the first 3-D polymeric structure such that the second structure latches onto the first structure; and
d) separating the surface-treated mold from the second 3-D polymeric structure to provide an assembled structure comprised of the second 3-D polymeric structure on the first 3-D polymeric structure.
2. The method of claim 1 further comprising the steps of:
a) providing a third 3-D polymeric structure in a second surface-treated mold;
b) pressing the third 3-D polymeric structure into the second 3-D polymeric structure such that the third structure latches onto the second structure, the second structure being part of the assembled structure;
d) separating the second surface-treated mold from the third 3-D polymeric structure to provide an augmented assembled structure comprised of the third 3-D polymeric structure on the assembled structure comprising the first and second 3-D polymeric structures.
3. The method of claim 2 , wherein the surface-treated molds are silane-treated.