Synthesis of top coat surface treatments for the orientation of thin film block copolymers

Abstract

Block copolymer self-assembly has demonstrated sub-optical lithographic resolution . High values of chi, the block copolymer interaction parameter, are required to achieve next-generation lithographic resolution . Unfortunately, high values of chi can lead to thin film orientation control difficulties , which are believed to be caused by large differences in the surface energy of each block relative to the substrate and the free surface. The substrate-block interface can be modified to achieve a surface energy intermediate to that of each individual block ; the air-polymer interface, however, presents additional complications. This thesis describes the synthesis of polymers for top coat surface treatments, which are designed to modify the surface energy of the air-block copolymer interface and enable block copolymer orientation control upon thermal annealing. Polymers with β-keto acid functionality were synthesized to allow polarity switching upon decarboxylation. Syntheses of anhydride containing polymers were established that provide another class of polarity switching materials.