A stable, high-mobility ZnO thin-film semiconductor was fabricated by thermal treatment of a solution-deposited thin film from a solution of Zn(OAc)(2)/2-ethanolamine in methoxyethanol. This ZnO thin-film semiconductor was composed of closely packed ZnO single crystals (similar to 30 to 50 nm) having a hexagonal structure assuming a preferred orientation with its c-axis perpendicular to the substrate. Field-effect mobility of 5-6 cm(2) V-1 s(-1) and current on-to-off ratio of 10(5)-10(6) were demonstrated with this ZnO thin-film semiconductor in thin-film transistors.