Evolution of Block Copolymer Lithography to Highly Ordered Square Arrays.
The manufacture of smaller, faster, more efficient microelectronic components is a major scientific and technological challenge, driven in part by a constant need for smaller lithographically defined features and patterns. Traditional self-assembling approaches based on block copolymer lithography spontaneously yield nanometer-sized hexagonal structures, but these features are not consistent with the industry-standard rectilinear coordinate system. We present a modular and hierarchical self-assembly strategy, combining supramolecular assembly of hydrogen-bonding units with controlled phase separation of diblock copolymers, for the generation of nanoscale square patterns. These square arrays will enable simplified addressability and circuit interconnection in integrated circuit manufacturing and nanotechnology.