Patterned vs. Rough Surfaces: Indium Tin Oxide (ITO) in Flexible Electronics (2015)

Undergraduates: Kristina Vrouwenvelder, Kai Shin, McKean Tompkins Qian Dong Yukihiro Hara

Faculty Advisor: Rene Lopez
Department: Chemistry

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The development of conductive materials for use in flexible substrates is currently of great interest. Flexible conductive substrates, with potential applications in electronics ranging from displays and touch screens to flexible thin-film transistors and photovoltaics, have previously been approached from an organic materials perspective. However, the inorganic material indium tin oxide (ITO) ¿¿¿ conductive, transparent, and easily deposited over large areas as a thin film - is a promising new material for these flexible substrates. We demonstrate the use of two patterning techniques to improve the conductivity of ITO on a flexible substrate: nanoscale photolithographic patterning to create an ordered, spring-like ITO structure on the substrate, and deep-reactive ion etching to ¿¿¿roughen¿¿¿ the polyethylene terephthalate (PET) surface and create random, nanoscale structures in the ITO.