Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Korea.
ACS Nano. 2013 Mar 26;7(3):1952-60. doi: 10.1021/nn3051264. Epub 2013 Mar 6.
The directed assembly of block copolymer nanostructures with large periods exceeding 100 nm remains challenging because the translational ordering of long-chained block copolymer is hindered by its very low chain mobility. Using a solvent-vapor annealing process with a neutral solvent, which was sequentially combined with a thermal annealing process, we demonstrate the rapid evolution of a perpendicularly oriented lamellar morphology in high molecular weight block copolymer films on neutral substrate. The synergy with the topographically patterned substrate facilitated unidirectionally structural development of ultrahigh molecular weight block copolymer thin films-even for the structures with a large period of 200 nm-leading to perfectly guided, parallel, and highly ordered line-arrays of perpendicularly oriented lamellae in the trenched confinement. This breakthrough strategy, which is applicable to nanolithographic pattern transfer to target substrates, can be a simple and efficient route to satisfy the demand for block copolymer assemblies with larger feature sizes on hundreds of nanometers scale.
具有大于 100nm 的大周期的嵌段共聚物纳米结构的定向组装仍然具有挑战性，因为长链嵌段共聚物的平移有序化受到其非常低的链流动性的阻碍。使用具有中性溶剂的溶剂-蒸汽退火工艺，该工艺依次与热退火工艺相结合，我们在中性基底上的高分子量嵌段共聚物薄膜中证明了垂直取向层状形态的快速演变。与具有形貌图案的基底的协同作用促进了超高分子量嵌段共聚物薄膜的单向结构发展——即使对于具有 200nm 大周期的结构也是如此——导致在沟槽限制中形成完美引导的、平行的、高度有序的垂直取向层片线阵。这种适用于纳米光刻图案转移到目标基底的突破性策略，可以成为满足在数百纳米范围内具有更大特征尺寸的嵌段共聚物组装的需求的简单而有效的途径。
