Deposition of Amorphous Zinc Indium Tin Oxide and Indium Tin Oxide Films on Flexible Poly(ether sulfone) Substrate Using RF Magnetron Co-sputtering System

Abstract

Zn–In–Sn-O (ZITO) and In–Sn-O (ITO) thin films were deposited at room temperature on poly(ether sulfone) (PES) substrates using a combinatorial rf magnetron co-sputtering system. The cationic contents of the films were varied using a compositionally combinatorial technique. The average optical transmittance of the ZITO films was >80% in the visible region. The ZITO films showed an amorphous phase regardless of the zinc content. A minimum resistivity of 4.1×10-4 Ω·cm was obtained at a zinc content of 8.9 at. % [Zn/(In + Zn + Sn)]. The amorphous ZITO films deposited on flexible substrates had good mechanical durability against external dynamic stress, as measured using a bending test. Overall, the characteristics of the ZITO films were comparable or superior to those of the amorphous ITO films, and thus ZITO films may serve as a viable, low-cost alternative for electrode applications in flexible organic light-emitting diodes or organic solar cells.