Sol-gel zinc tin oxide (ZTO) thin film transistors (TFTs) were fabricated at a low temperature of 250 degrees C using an ultraviolet (UV) photo-annealing process. A stable ZTO sol-gel solution was produced and showed considerable absorption in UV due to the incorporation of a chelating agent, acetylacetone, which also acts as a UV-activator. The UV photo-annealing and vacuum annealing improve the electrical performance of the ZTO TFT with mobility of 2 cm(2)/V.s by effective dissociation of organic groups and promotion of metal-oxide-metal bonds formation, confirmed by X-ray photoelectron spectroscopy of the ZTO films. (C) 2012 The Electrochemical Society. [DOI:10.1149/2.013204esl] All rights reserved.