title: Effect of the annealing ambient on the electrical characteristics of the amorphous InGaZnO thin film transistors.
abstract: The influence of the thermal annealing on the amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) under different ambient gases has been systematically addressed. The chemical bonding states and transfer characteristics of a-IGZO TFTs show evident dependence on the annealing ambient gas. For the a-IGZO TFTs in the oxygen ambient annealing at 250 degrees C for 30 mins exhibited a maximum field effect mobility (max muFE) of 9.36 cm2/V x s, on/off current ratio of 6.12 x 10(10), and a subthreshold slope (SS) of 0.21 V/decade. Respectively, the as-deposited ones without annealing possess a max muFE of 6.61 cm2/V x s, on/off current ratio of 4.58 x 10(8), and a SS of 0.46 V/decade. In contrast, the a-IGZO TFTs annealed at 250 degrees C for 30 mins in the nitrogen ambient would be degraded to have a max muFE of 0.18 cm2/V x s, on/off current ratio of 2.22 x 10(4), and a SS of 7.37 V/decade, corresponding. It is attributed to the content of the oxygen vacancies, according the x-ray photoelectron spectroscopy (XPS) analyze of the three different samples.
authors.affiliation: Department of Electronics Engineering and Institute of Electronics, National Chiao Tung University, Hsinchu 30010, Taiwan.
authors.forename: Yu-Chih
authors.initials: YC
authors.lastname: Huang
authors.forename: Po-Yu
authors.initials: PY
authors.lastname: Yang
authors.forename: Hau-Yuan
authors.initials: HY
authors.lastname: Huang
authors.forename: Shui-Jinn
authors.initials: SJ
authors.lastname: Wang
authors.forename: Huang-Chung
authors.initials: HC
authors.lastname: Cheng