Using Self-Assembled Cyclic and Linear Block Copolymer Blends as Templates for Sub-10 nm Soft Lithography

Tulane University, New Orleans LA

Investigators

Abstract

Thanks to advancements in the microelectronics industry over the past fifty years, today's smart phones are more powerful and less expensive than the best supercomputers of the 1970's and 1980's. These technologies impact nearly every facet of life - from entertainment and personal communication to healthcare and national defense. Currently, computer chip manufacturing uses lasers to pattern ever-smaller features to make faster processors and create higher density data storage. However, the cost of patterning using this approach is rising faster than the benefits afforded by smaller features, necessitating the development of new manufacturing approaches to advance the field and maintain U.S. status as a world leader in advanced manufacturing. This grant supports fundamental research into an alternative patterning method that uses block copolymers, a type of rubbery plastic that naturally forms nanoscale patterns through a process called self-assembly. The research generates the knowledge necessary to transform the manufacture of next-generation nanoelectronics that can be incorporated into communication devices, security technologies, health monitors, and disease treatments. These advances contribute to national prosperity, health and security. This project brings together an interdisciplinary team of researchers with expertise in molecular simulations and experimental materials synthesis to train a diverse cohort of high school, undergraduate, and doctoral students that will drive innovation in advanced materials manufacturing. Block copolymer self-assembly offers a direct manufacturing route to nanostructure formation that eliminates the need for more complex, time-consuming, and costly laser-based patterning methods. This project investigates the phase behavior of strongly segregated cyclic block copolymers, which show promise for accessing sub-10 nm feature sizes and stabilizing polymer thin films against dewetting. The project uses complementary experimental and computational approaches to not only compare cyclic block copolymers to linear analogues but also to evaluate nanostructure quality in cyclic/linear block copolymer blends as templates for nanolithography. To realize manufacturing scalability of this approach, two critical challenges are addressed: First, using small quantities of cyclic block copolymer as a structure-directing and film-stabilizing agent to achieve target lithographic domain sizes while minimizing the amount of specialty cyclic block copolymer. Second, if shorter reaction times and less dilute solution conditions are used in the synthesis of cyclic molecules to improve yield, understanding what linear impurities are generated and how do they impact self-assembly. Throughout the project, insight into the thermodynamic origin of the structures formed are derived from molecular simulations to guide and optimize experimental design. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.