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Yaroslav V. Kudryavtsev
Orientation сontrol of the hexagonal and lamellar phases
in thin block copolymer films using in-plane electric field
It is well-known that electric fields can align microphase-separated patterns in block copolymers on the tens of microns scale along the field lines. We study the situation when a thin film of a high molar mass polystyrene–poly(vinyl pyridine) diblock copolymer, with an already existing standing cylinder or fingerprint structure, is placed under DC or AC field parallel to the substrate. Combination of atomic force microscopy observations with self-consistent field theory calculations allows us to interpret the apparent changes in the film morphology. We discuss the effects of solvent vapor annealing and doping the copolymer with gold nanoparticles and the role of such factors as the exposure time, field strength and frequency.