| 초록 |
Block copolymers are well-known to spontaneously form a variety of nanostructures. In the case of thin films, the orientation of such nanostructure is additionally affected by a substrate and a surface. This often leads to morphologies oriented in parallel with the substrate. However, for the fabrication, perpendicularly oriented block templates are often preferred. In present study, we present a new processing route, based on the use of surfactants, to control the orientation of polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) thin films. The addition of surfactant, preferably interacting with PMMA domain, modifies the surface energy of the system, resulting in the perpendicular orientation independent of substrates used. For the high aspect ratio and defect-free nanodomains in perpendicular orientation, we also combined the surfactant-assisted self-assembly with the directed self-assembly involving chemically patterned substrates, which were realized by Extreme-UV Lithography. |
