Computational Paradigm for Simulating Free Boundary Diblock Copolymers

University Of California-Santa Barbara, Santa Barbara CA

Investigators

Abstract

This project combines modeling with numerical methods for the investigation of the self-assembly of block copolymers. In particular, this project will result in the development of efficient and predictive computational tools that predict the self-assembly of block copolymers that present a free boundary. In addition, this formalism will be used to develop a methodology for solving the inverse problem of finding the geometry of a mask component that will direct the self-assembly of copolymer towards a target design. Copolymers are ubiquitous in science and engineering, they provide unique characteristics that modern industrial processes depend on to keep up with Moore's law and constitute an excellent model system for scientific studies of self-assembly. Therefore, the research has a broader impact in the multiscale modeling and computation of more general self-assembly processes that arise in other physical and biological sciences. The specific objectives of the project are: 1) to develop an innovative, effective computational framework for predicting the self-assembly of block copolymer in both two and three spatial dimensions in the case of free surfaces; 2) to use this framework to understand the coupling between thermodynamic, kinetic and surface tension forces on the self-assembly and on the geometry of the free surface; 3) to apply this framework to the prediction of a template's geometry that will direct the self-assembly towards a target design. Diblock copolymers are melts made of molecular chains with two chemically different species along their backbone that self-assemble into ordered structures used in high density hard drives, drug delivery systems, magnetic dots, nano-pores, nano-wires, membranes with tailored nano-scales porosity, in battery fuel cells and silicon capacitors. Since the surface of the melt plays a crucial role in the self-assembly, this research will develop a computational paradigm that enables the simulation of the self-assembly of free boundary diblock copolymers. This paradigm combines the level-set methodology for dynamic interfaces with the self-consistent field theory describing the self-assembly of diblock copolymers at equilibrium. These studies will be carried out by the PI who works in an interdisciplinary environment with close collaborations with experts in the field of diblock copolymers that bring forth a synergy of modeling and computational ideas. The broader impacts of the work also include 1) the training of computational students in an interdisciplinary, international team, 2) the integration of undergraduate from underrepresented groups, and 3) potential industrial relevance.