In this letter, indium-titanium-zinc-oxide thin-film transistors with zirconium oxide (ZrOx) gate dielectric were fabricated at room temperature. In the devices, an ultra-thin ZrOx layer was formed as the gate dielectric by sol-gel process followed by ultraviolet (UV) irradiation. The devices can be operated under a voltage of 4 V. Enhancement mode operations with a high field-effect mobility of 48.9 cm(2)/V s, a threshold voltage of 1.4 V. a subthreshold swing of 0.2 V/decade, and an on/off current ratio of 10(6) were realized. Our results demonstrate that UV-irradiated ZrOx dielectric is a promising gate dielectric candidate for high-performance oxide devices. (C) 2013 Elsevier B.V. All rights reserved.