Title: Temperature-Dependent Transfer Characteristics of Low Turn-On Voltage InGaZnO Metal-Oxide Devices With Thin Titanium Oxide Capping Layers
Authors: Hsu, Hsiao-Hsuan
Cheng, Chun-Hu
Chiou, Ping
Chiu, Yu-Chien
Yen, Shiang-Shiou
Tung, Chien-Hung
Chang, Chun-Yen
Department of Electronics Engineering and Institute of Electronics
Keywords: Indium-gallium-zinc oxide (IGZO);thin-film transistor (TFT);titanium oxide (TiOx);zirconium oxide (ZrO2)
Issue Date: Jun-2015
Abstract: This paper reports an InGaZnO thin-film transistor involving a wide bandgap gate dielectric of ZrO2 and IGZO/TiOx channel stack. According to our experimental results, the IGZO TFT with a thin TiOx channel capping layer shows good device integrity of a low threshold voltage of 0.37 V, a small sub-threshold swing of 77 mV/decade, and a high mobility of 33 cm(2)/V.s under a low drive voltage of < 2 V. We also demonstrate that the significantly improved electrical property is mainly contributed by the enhanced channel electric field after TiOx capping, associated with maximizing charge accumulated capability. The favorable high-temperature transfer characteristics are also obtained in IGZO/TiOx TFT, indicating a weak Fermi-level pinning in IGZO/TiOx channel structure. With the operating temperature increasing further, the thermal activated effect shall dominate IGZO channel property beyond percolation conduction.
URI: http://dx.doi.org/10.1109/JDT.2014.2355876
ISSN: 1551-319X
DOI: 10.1109/JDT.2014.2355876
Volume: 11
Issue: 6
Begin Page: 512
End Page: 517
Appears in Collections:Articles