Abstract
| - Thin films of block copolymers were manipulated on two different length scales simultaneously by use of an electric field. Electrostatic pressure generated at the surface of a block copolymerfilm between two electrodes with an air gap separating the surface of the block copolymer film and theupper electrode produced, as in homopolymer films, an array of hexagonally ordered columns, tens ofmicrons in size, that spanned between the two electrodes. Within each column the diblock copolymermicrophase separated into hexagonally packed cylindrical microdomains, tens of nanometers in size. Theorientation of these microdomains was controlled by the interfacial energies of each block with the surfacesof the electrode and the direction of the applied field. Microdomain alignment parallel to and normal tothe applied field could be controlled by the strength of the interfacial interactions. The results show anovel means by which block copolymers can be controlled on two different length scales simultaneouslyand present a new route toward fabricating functional nanoscopic structures in thin polymer films.
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