title: From two-dimensional colloidal self-assembly to three-dimensional nanolithography.
abstract: A number of "top-down" lithographic and "bottom-up" self-assembly methods have been developed to fabricate three-dimensional (3D) nanostructures to support the recent advances in nanotechnology. But they are limited by a number of factors such as fabrication cost, pattern resolution, and/or flexibility of geometry. Here we present a 3D nanolithography process that utilizes self-assembled nanospheres to create a periodic array of focal spots, which are then replicated across multiple depth in a transparent medium according to the Talbot effect. The Talbot field then exposes a pattern onto the underlying photoresist, recording the 3D intensity distribution. We have demonstrated designable complex 3D periodic structures with 80 nm minimum feature size, roughly one-fourth of the operating wavelength. This approach combines 2D colloidal self-assembly and 3D phase lithography, is robust, cost-effective, and widely applicable to nanoscale research and manufacturing.
authors.affiliation: Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States. chichang@mit.edu
authors.forename: C-H
authors.initials: CH
authors.lastname: Chang
authors.forename: L
authors.initials: L
authors.lastname: Tian
authors.forename: W R
authors.initials: WR
authors.lastname: Hesse
authors.forename: H
authors.initials: H
authors.lastname: Gao
authors.forename: H J
authors.initials: HJ
authors.lastname: Choi
authors.forename: J-G
authors.initials: JG
authors.lastname: Kim
authors.forename: M
authors.initials: M
authors.lastname: Siddiqui
authors.forename: G
authors.initials: G
authors.lastname: Barbastathis
mesh_terms: D003102:Colloids / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D003102:Colloids