Electronic devices manufactured from organic compounds are a promising alternative to those containing active layers derived from inorganic materials. The ability to fine tune material performance through chemical synthesis, and the inherent flexibility, stretchability, and biological compatibility offered by organic materials, offer new avenues for integrated, flexible, and large-area electronics applications. The internal material distribution, or morphology, of the manufactured devices critically influences performance. Understanding how the morphology of the thin-film active layer is affected by the chemical composition of the constituent organic compounds and manufacturing conditions will enable the efficient and accelerated design of high performance electronic devices. Computational modeling is a well-known approach to understanding morphology formation during manufacturing, with most current computational approaches limited to analyzing phenomena at one scale. However, it is now understood that both molecular structure and mesoscale conditions interactively affect morphology formation. This award supports fundamental research to provide needed knowledge to understand morphology formation using a multiscale theoretical approach. The results from this research will have broad applicability across a diverse spectrum of technologies, such as solar cells, diode lighting, flexible displays, and bioelectronics, thus directly benefiting the U.S. economy and society. The research is based on a tight integration of chemistry and engineering and involves concepts from materials science, chemistry, mathematical modeling, and scientific computing. The research and associated workforce development activities will help broaden participation of underrepresented groups and will offer students a solid foundation in engineering, chemistry, computational science, and the development of energy and electronics technologies.
This research will integrate first principles and molecular methods with meso-scale continuum methods to create a cohesive, atomistic-continuum framework. The framework will be used to model morphology formation during solution manufacture of thin films of a class of molecules (containing oligoacene cores with trialkylsilylethynyl side groups) that have shown promise for creating high performing multifunctional electronic devices. Molecular simulations will be used to compute free energies, solubilities and other material properties that will be used by the meso-scale continuum simulations. The research will fill the knowledge gap on the interplay between molecular structure and solution conditions on (a) aggregation, (b) the early stages of film growth and the impact of chemisorbed surface modifiers, and (c) the complexity of OSC film formation in multicomponent polymer-molecule blends. This research will help establish relationships between molecular structure, manufacturing conditions, and the resultant material morphology.
