Ordering and orientation of giant nanostructures from high-molecular-weight block copolymer via solvent vapor annealing process

Ordering and orientation of high-molecular-weight (HMW) block copolymer (BCP) are challenging issues for recent technology to push the limit of nanoscopic size to hundreds-of-nanometers scale. HMW polystyrene-b-poly(methyl methacrylate)s (PS-b-PMMAs) were used to actualize larger feature sizes of giant lamellar and gyroid (GYR) nanostructures. The solvent vapor annealing (SVA) process was exploited to develop the long-range order nanostructures in the HMW BCP films. Directed orientation of nanostructures and the defect annihilation are discussed in terms of the interfacial interactions on the substrates and topographic trenches to design well-defined regular nanopatterns.