High-Performance a-IGZO Thin-Film Transistor Using $ \hbox{Ta}_{2}\hbox{O}_{5}$ Gate Dielectric

Abstract

In this letter, we report the fabrication of an amorphous indium gallium zinc oxide (a-IGZO) thin-film transistor with a high-k dielectric layer on a glass substrate. The room-temperature-deposited a-IGZO channel with Ta <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sub> exhibits the following operating characteristics: a threshold voltage of 0.25 V, a drain-source current on/off ratio of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> , a subthreshold gate voltage swing of 0.61 V/decade, and a high field-effect mobility of 61.5 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /V·s; these characteristics make it suitable for use as a switching transistor and in low-power applications.