So Youn Kim
Ph.D. Institution: University of Illinois at Urbana-Champaign
Microphase separation in block copolymer (BCP) thin films can create dense, periodic structures. Due to this property BCPs give fine resolution, cost- effectiveness and scalability in nanolithographic applications. For example, cylinder forming BCPs can be used as etch masks generating nanowires. However, high aspect ratio of nanostructures in fabrication requires strong etch contrast between two blocks of the polymer. We use metal containing BCPs such as polystyrene-b-polyferrocenylsilane (PS-b-PFS) or metallized polystyrene-b-poly-2-vinylpyridne (PS-P2VP) providing strong etch-resistance for a metallized block. In both cases shear stress can produce alignment over centimeter-scale areas. Then, the aligned patterns can be transferred via reactive ion etching into amorphous silicon deposited onto a quartz wafer to fabricate silicon nanowires. We are currently interested in nanofabrications employing various BCPs as effective templates and shear stress to generate long-range alignment.