The book "Zinc Oxide Thin-Film Transistors" offers a comprehensive examination of the properties and applications of zinc oxide (ZnO) as an n-type semiconductor in thin-film transistor (TFT) technology. Zinc oxide has proven to be promising due to its excellent optical, electrical, and catalytic properties. This publication describes the methods for producing ZnO thin films through reactive radio frequency magnetron sputtering, with the process conducted at room temperature. A central concern of this work is to ensure the stable semiconductor properties of the ZnO films, which serve as the active channel in TFTs. Furthermore, the role of intrinsic point defects in relation to the performance and stability of the devices is investigated, as well as the effects of oxygen adsorption on the properties of the TFTs. This research is significant for the advancement of transparent semiconductor materials and their applications in various technological fields.