EPSCoR Research Fellows: NSF: Low-Temperature Plasma-Assisted Aerosol Printing of High-k Inorganic Dielectrics for Flexible Electronics

This Research Infrastructure Improvement (RII) EPSCoR Research Fellows project provides a fellowship to an Assistant Professor and training for a graduate student at the Oklahoma State University (OSU). The work will be conducted in collaboration with Dr. Margaret Samuels at the NASA Goddard Space Flight Center (GSFC). Through the fellowship, the Principal Investigator (PI) will develop a way to print the thin insulating layers that every electronic device requires. The best insulating materials currently require temperatures that destroy the bendable plastics used in flexible devices such as wearable health monitors and aircraft sensors. The process being studied passes liquid ink through a plasma, an energized gas that converts the ink into a solid insulating film as it prints, with no separate heating step. The project will identify the printing conditions that yield high-quality films and measure how those films perform in devices. The fellowship will strengthen Oklahoma's advanced manufacturing capacity, prepare students for the state’s aerospace and defense workforce, and build a lasting partnership between OSU and NASA. This project will establish how an atmospheric-pressure plasma converts an aerosolized precursor into a hafnium oxide dielectric during millisecond flight. Plasma-assisted printing of metals by reductive chemistry is established; the oxidative pathway, in which plasma-generated oxygen radicals must remove ligands and condense the oxide network simultaneously, has not been studied. The PI will test whether the balance between reactive species supply and precursor loading governs the film's structural identity, and whether structural identity alone determines dielectric performance. Optical emission spectroscopy will quantify this balance and anchor a process-structure regime map spanning film phase, stoichiometry, and carbon content. Capacitors from each regime will then be measured at NASA GSFC for permittivity, leakage, and breakdown against thermally annealed references of matched structure, testing whether the conversion pathway leaves an electrical fingerprint. The fellowship will establish the diagnostic instrumentation and device-level testing expertise at OSU, train a doctoral student at NASA, and supply datasets for additive manufacturing courses. This project is supported by the EPSCoR Research Infrastructure Improvement Program: EPSCoR Research Fellows (ERF). The ERF program supports early- and mid-career investigators in eligible jurisdictions to develop collaborations at the nation’s private, government or academic research institutions. 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.