High Mobility Bilayer Metal–Oxide Thin Film Transistors Using Titanium-Doped InGaZnO

Abstract

We report a high performance indium-gallium-zinc oxide (IGZO)/IGZO:Ti bilayer metal–oxide thin-film transistor (TFT) with a low drive voltage of <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${&lt;}{\rm 2}~{\rm V}$</tex></formula> . Compared with conventional IGZO TFTs, the novel bilayer metal–oxide TFTs through IGZO thickness modulation can reach the lowest off current of <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$1.6\times 10^{-11}~{\rm A}$</tex></formula> , smallest sub-threshold swing of 73 mV/decade, and highest mobility of 63 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${\rm cm}^{2}$</tex></formula> /Vs, which may create the potential application for high resolution display.