Credit: Brookhaven National Laboratory
Conventionally, block copolymers self-assemble into a limited range of morphologies, such as spheres and lamellae. But by using appropriate block copolymer blends and a chemically patterned substrate that contains the "instructions" for which morphologies appear where, scientists can significantly expand this range. Nowak, Yager, and other CFN scientists recently obtained four different nanostructures—dots, lines, horizontal lamellae, and hexagonally perforated lamellae—in predetermined regions of a single substrate.