High-performance In-Zn-O thin-film transistors with a soluble processed ZrO2 gate insulator

Spin-coated zirconium oxide films were used as a gate dielectric for low-voltage, high performance indium zinc oxide (IZO) thin-film transistors (TFTs). The ZrO2 films annealed at 400 degrees C showed a low gate leakage current density of 2 x 10(-8) A/cm(2) at an electric field of 2 MV/cm. This was attributed to the low impurity content and high crystalline quality. Therefore, the IZO TFTs with a soluble ZrO2 gate insulator exhibited a high field effect mobility of 23.4 cm(2)/V s, excellent subthreshold gate swing of 70 mV/decade and a reasonable I-on/off ratio of approximate to 10(6). These TFTs operated at low voltages (approximate to 3.0 V) and showed high drain current drive capability, enabling oxide TFTs with a soluble processed high-k dielectric for use in backplane electronics for low-power mobile display applications. (c) 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim