Ryu, In Hyu Kim, Yong Joo Jung, Yeon Sik Lim, Jong Sung Ross, Caroline A. Son, Jeong Gon 2024-01-20T01:31:51Z 2024-01-20T01:31:51Z 2021-09-01 2017-05-24 1944-8244 https://pubs.kist.re.kr/handle/201004/122724 Block copolymers (BCPs) with a high Flory-Huggins interaction parameter (chi) can form well-defined sub-10 nm periodic structures and can be used as a template for fabrication of various functional nanostructures. However, the large difference of surface energy between the blocks commonly found in high-chi BCPs makes it challenging to stabilize a useful gyroid morphology in thin film form. Here, we used an interfacial-energy-tailored top-coat on a blended film of a polystyrene-block-polydimethylsiloxane (PS-b-PDMS) BCP and a low-molecular-weight PDMS homopolymer with a hydrophilic end functional group. The top coat consisted of a random mixture of 40% hydrolyzed poly(vinyl acetate)-random-poly(vinly alcohol) (PVA-r-PVAc, PVA40) and PVAc homopolymer. At the optimized top-coat composition, gyroid nanostructures with sub-10 nm strut width were achieved down to similar to 125 nm film thickness, which is only 3 times the lattice parameter of the gyroid structure. This is in marked contrast with a mixed morphology of gyroid and cylinders obtained for other compositions of the top coat. Self-consistent field theoretic simulations were used to understand the effect of the interfacial energy between the top coat and BCP/homopolymer blends on the phase transition behavior of the BCP/homopolymer films. English American Chemical Society PERPENDICULAR ORIENTATION SOLVENT EVAPORATION INDUCED ALIGNMENT SURFACE-TENSION LITHOGRAPHY POLYMERS DOMAINS BLENDS NANOLITHOGRAPHY NANOSTRUCTURES Interfacial Energy-Controlled Top Coats for Gyroid/Cylinder Phase Transitions of Polystyrene-block-polydimethylsiloxane Block Copolymer Thin Films Article 10.1021/acsami.7b02910 1 ACS Applied Materials & Interfaces, v.9, no.20, pp.17428 - 17435 ACS Applied Materials & Interfaces 9 20 17428 17435 scie scopus 000402498600074 2-s2.0-85019752968 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article PERPENDICULAR ORIENTATION SOLVENT EVAPORATION INDUCED ALIGNMENT SURFACE-TENSION LITHOGRAPHY POLYMERS DOMAINS BLENDS NANOLITHOGRAPHY NANOSTRUCTURES gyroid thin film block copolymer self-assembly sub-10 nm patterning top coat phase transition SCFT simulation