title: Highly ordered square arrays from a templated ABC triblock terpolymer.
abstract: Square-symmetry patterns are of interest in nanolithography but are not easily obtained from self-assembly of a diblock copolymer. Instead, we demonstrate highly ordered 44 nm period square patterns formed in a thin film of polyisoprene-block-polystyrene-block-polyferrocenylsilane (PI-b-PS-b-PFS) triblock terpolymer blended with 15% PS homopolymer by controlling the film thickness, solvent anneal conditions, the surface chemistry and topography of the substrates. The square patterns consist of PFS pillars that remained after removal of the PI and PS with an oxygen plasma. On an unpatterned smooth substrate, the average grain size of the square pattern was increased dramatically to several micrometers by the use of brush layers and specific solvent anneal conditions. Templated self-assembly of well-ordered square patterns was demonstrated on substrates containing nanoscale topographical sidewalls and posts, written by electron beam lithography, in which the sidewalls and base of the substrate were independently chemically functionalized.
authors.affiliation: Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
authors.forename: Jeong Gon
authors.initials: JG
authors.lastname: Son
authors.forename: Jessica
authors.initials: J
authors.lastname: Gwyther
authors.forename: Jae-Byum
authors.initials: JB
authors.lastname: Chang
authors.forename: Karl K
authors.initials: KK
authors.lastname: Berggren
authors.forename: Ian
authors.initials: I
authors.lastname: Manners
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Ross
mesh_terms: D008567:Membranes, Artificial; D036103:Nanotechnology; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D008567:Membranes, Artificial; D011108:Polymers