High Mobility Solution-Processed Hafnium Indium Zinc Oxide TFT With an Al-Doped <inline-formula> <tex-math notation="TeX">${\rm ZrO}_{2}$ </tex-math></inline-formula> Gate Dielectric

Abstract

In this letter, we report a solution-processed hafnium indium zinc oxide (HIZO) thin-film transistors (TFTs) with an Al-doped ZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (AZO) gate dielectric. The AZO thin films were identified as an amorphous phase up to the annealing temperature of 600 °C and had a smooth surface with root-mean-square roughness of <;0.35 nm. The relative dielectric constant of AZO thin film annealed at 400 °C is 19.67. And HIZO TFTs with AZO gate oxide exhibited a high saturation field-effect mobility of 18.1 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /Vs, a small subthreshold swing of 0.4 V/decade, and a high ON/OFF ratio of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">7</sup> , which can satisfy the backplate requirements for flat panel displays.