LETTER pubs.acs.org/NanoLett Highly Tunable Self-Assembled Nanostructures from a

bS Supporting Information Self-assembly of organic materials has become an essentialprocess in the fabrication of nanostructures, with particular application to pattern generation for next-generation nanoscale lithography. The microelectronics industry is facing challenges arising from the increasing cost and limited resolution of deep-UV optical lithography, and it is expected that bottom-up approaches using organic molecules will provide a strategy for next-generation nanolithography. Directed self-assembly (DSA) based on polymers or nanoparticles promises very high resolution and outstanding manufacturability of sub-20-nm structures.114 In particular, DSA of block copolymers (BCPs) has shown great advantages such as feature sizes below∼10 nm and good compat-ibility with other planar processes and thus has been a topic of enormous research activity for the past decade.16,813,1526 The microphase separation of diblock copolymers is thermo