seed projects

Sarah Swisher: Seed of Opportunity: Flexible Electronics

Printing solution-based materials onto low-cost plastic substrates (“additive manufacturing”) is an appealing way to make flexible electronic devices because of its simplicity, low capital investment, and low-cost manufacturing. However, to obtain high-quality electronic thin films from liquid inks, thermal annealing treatments are typically required to improve the semiconductor transport properties. Achieving high-performance semiconductor materials currently requires fabrication processes that are not compatible with flexible plastic substrates, which means electrical performance is sacrificed to gain mechanical flexibility.

To overcome this fundamental tradeoff between electrical performance and compatibility with flexible substrates, Swisher is developing customized metal oxide colloidal nanocrystal inks (e.g., In-Ga-Zn-O or “IGZO”) to inkjet-print transistors. IGZO exhibits excellent electron transport, even in highly disordered films, and – unlike common sol-gel techniques – colloidal nanocrystals can be precisely controlled to produce the desired composition, crystal structure, and surface functionality. Swisher is also pursuing processing techniques such as photonic curing that will yield high-performance thin-film transistors (TFTs) on flexible plastic substrates.

Funded by the National Science Foundation through the University of Minnesota MRSEC under Award Number DMR-1420013