In this study, we compare the electrical properties of inverted-coplanar-type InGaZnO thin-film transistors (IGZO TFTs) deposited by RF sputtering at room temperature on a thermally grown SiO(2) gate dielectric or a hafnium oxide (HfO(2)) gate dielectric. The fabricated HfO(2)/IGZO TFTs have higher field-effect mobility than the SiO(2)/IGZO TFTs. The HfO(2)/InGaZnO TFTs show good performance with a high field-effect mobility of 25.8 cm(2) V(-1) s(-1), a low sub-threshold swing of 90 mV dec(-1), and a threshold voltage of 0.67 V, respectively. (C) 2010 Elsevier B.V. All rights reserved.