標題: Electrical characteristics of amorphous In-Ga-Zn-O thin-film transistors prepared by radio frequency magnetron sputtering with varying oxygen flows
作者: Lee, Yih-Shing
Yen, Tung-Wei
Lin, Cheng-I
Lin, Horng-Chih
Yeh, Yun
電子工程學系及電子研究所
Department of Electronics Engineering and Institute of Electronics
關鍵字: Amorphous indium-gallium-zinc oxide (a-IGZO);Oxygen flow;Carrier concentration;Total resistance method;Composition
公開日期: 1-七月-2014
摘要: This study investigates impacts of oxygen flow during the deposition of amorphous indium-gallium-zinc oxide (a-IGZO) channel layer with a radio frequency (r.f.) magnetron sputter on the electrical characteristics of the fabricated thin-film transistors (TFTs). Results indicate that as the film was deposited with a higher oxygen flow, the transfer curves are positively shifted while the field-effect mobility (mu(FE)) is significantly decreased. To get more insight about the effects, channel resistance (R-CH) and the parasitic source-to-drain resistance (R-SD) of the fabricated devices are extracted using the total resistance method. The extracted a-IGZO channel resistance per unit length (r(ch)) and R-SD are found to increase while the extracted effective mobility (mu(E)) is decreased with increasing oxygen flow during sputtering. These observations are postulated to be related the decrease in the In/(In + Ga + Zn) ratio and the increase in the Zn/(In + Ga + Zn) ratio of the a-IGZO films with increasing the oxygen flow rate which lead to higher resistivity and lower carrier concentration. The extracted R-SD can be comparable with R-CH for the devices prepared with high oxygen flow, resulting in the roll-off of mu(FE) as the channel length is shorter than 20 mu m. (C) 2014 Elsevier B.V. All rights reserved.
URI: http://dx.doi.org/10.1016/j.displa.2014.05.005
http://hdl.handle.net/11536/147743
ISSN: 0141-9382
DOI: 10.1016/j.displa.2014.05.005
期刊: DISPLAYS
Volume: 35
起始頁: 165
結束頁: 170
顯示於類別:期刊論文