| 초록 |
Directed self-assembly (DSA) of block copolymers (BCPs) with a high Flory–Huggins interaction parameter (χ) has received much attention, due the excellent pattern resolution, cost-effectiveness, and simple process. In general, various highly ordered sub-20 nm patterns can be effectively generated using topographic templates fabricated by photolithography, such as line, dot, hole, and lamella structures. However, the in-depth research on templated self-assembly of BCPs on bare surfaces without any artificial guiding templates has not been reported yet. Here, we introduce a novel method to induce the self-assembly of high-χ BCPs by employing grain boundary surfaces of metals as guiding templates. We systemically demonstrate how to control the self-assembly of poly(styrene-b-dimethylsiloxane) (PS-b-PDMS) BCPs by precisely controlling the depth of grain boundaries of the metal surfaces and molecular weight (MW) of the BCP thin film, showing the well-ordered SiOx line and dot patterns with sub-20 nm. In addition, we show various self-assembled BCP patterns within the controlled grain boundaries of diverse metals, such as iron, brass, and stainless steel. We expect that this approach can be applicable to the other BCP systems and desirable materials surfaces with unusual geometries. |
