Solid-State Electronics, Vol.133, 6-9, 2017
The electrical performance and gate bias stability of an amorphous InGaZnO thin-film transistor with HfO2 high-k dielectrics
In this study, we set out to fabricate an amorphous indium gallium zinc oxide (a-IGZO) thin-film transistor (TFT) with SiNx/HfO2/SiNX. (SHS) sandwiched dielectrics. The J-V and C-V of this SHS film were extracted by the Au/p-Si/SHS/Ti structure. At room temperature the a-IGZO with SHS dielectrics showed the following electrical properties: a threshold voltage of 2.9 V, a subthreshold slope of 0.35 V/decade, an on/off current ratio of 3.5 x 10(7), and a mobility of 12.8 cm(2) V-1 s(-1). Finally, we tested the influence of gate bias stress on the TFT, and the result showed that the threshold voltage shifted to a positive voltage when applying a positive gate voltage to the TFT. (C) 2017 Elsevier Ltd. All rights reserved.
Keywords:HfO2;Stacked dielectrics;Transfer characteristics;Threshold voltage shift;Negative and positive gate bias stress