Effect of Zinc/Tin Composition Ratio on the Operational Stability of Solution-Processed Zinc–Tin–Oxide Thin-Film Transistors

Variation of Zn:Sn atomic composition ratio in zinc-tin-oxide (ZTO) thin films induced a dramatic change in the microstructure and also strongly influenced the device performance and operational stability of ZTO thin-film transistors (TFTs). The large variation of threshold voltage shift under gate bias stress appears to be closely correlated to the excessive or deficient Sn content and the oxidation potentials of the metallic components as well as environmental effects. It is noted that the optimum Zn:Sn atomic composition ratio in ZTO films can improve the device performance and operational stability of the solution-processed ZTO TFTs.