Low Voltage Driven, Stable Solution-Processed Zinc-Tin-Oxide TFT with HfOy and AlOx Stack Gate Dielectric

We report on low voltage driven, solution processed zinc-tin oxide (ZTO) transistors with a spin-coated hafnium oxide (HfOy) and aluminum oxide (AlOx) stack gate insulator (HfOy/AlOx). The ZTO TFT with a HfOy/AlOx dielectric processed at the maximum temperature of 400 degrees C exhibits the field-effect mobility of 3.84 cm(2)/V s, subthreshold swing of 117 mV/dec., and threshold voltage (V-th) of 0.84 V. The positive gate bias stress degradation of V-th with time follows a stretched exponential behavior with a time constant of 1.13 x 10(7) s, indicating stable TFT. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.017202ssl] All rights reserved.