Scaling the fabrication of thin films from the laboratory to manufacturing floor has been a difficult and time-consuming process. This is due in part to a lack of understanding important factors associated with the scalability of materials, in addition to the lack of advanced manufacturing approaches to fabricate thin films with desired properties, quality and/or functionality, at low cost and/or high speed. This is due, in part, to the difference in scale and approach between the discovery and development of new functional thin film materials, in the lab, and the use of scaled manufacturing techniques. Multilayer thin film devices are spread across many existing and emerging technological areas, including organic solar cells, displays, sensors, solid-state lighting, ubiquitous smart devices, and other applications. Thin organic films and film multilayers will play an increasingly important role in the formation of new products that demand high performance but low-cost. These thin films are typically formed from liquid films deposited onto and wetting mechanical supports or often flexible plastic substrates. In this research, the mechanisms that limit the scaling of emerging devices due to the interactions of fluids coated on dissimilar surfaces are elucidated and paths leading to manufacturability developed. This work supports the need for decreasing manufacturing costs and increasing the manufacturing rate of multilayer thin films. The grant enables the participation of undergraduates, principally from underrepresented groups, into the research activities.
The objective of this study is to investigate the influence of material properties and processing conditions on the ability to coat low viscosity electrode polymer fluids onto flexible substrates, to produce complex multilayer heterogeneous patterns, which will advance manufacturing knowledge for fabricating 3D thin film structures used in flexible electronics. The diverse range of defects that can be traced back to interfacial phenomena substantiates the importance of understanding the process-structure relationship of patterned heterogeneous thin film, when using scalable high-throughput processes. A unique manufacturing method called slot die printing or extrusion on-demand will be used for this experimental study. The investigation consists of three thrusts: Thrust 1 Thin Film Formation, Thrust 2, Interfacial Phenomena and Thin Film Stability, and Thrust 3, Thin Film Characterization and Analysis, to gain a basic understanding of the interfacial phenomena (wetting, spread, and adhesion) during solution coating onto heterogeneous surfaces, to elucidate mechanisms that impact the process-structure relationship of multilayer thin films. The work will further develop continuous roll-to-roll manufacture of complex multilayer films from solution, using a monolithic approach, thereby inherently decreasing fabrication cost and waste compared to traditional methods.
