Effects of Post-Deposition Annealing Atmosphere and Duration on Sol-Gel Derived Amorphous Indium-Zinc-Oxide Thin Film Transistors

Abstract

This work shows the effects of post-deposition annealing atmosphere and duration on the properties of sol-gel derived amorphous indium zinc oxide thin film transistors (a-IZO TFTs). Two different post-deposition annealing atmospheres, nitrogen and oxygen, were used in this study. Experimental results showed that the O-2-annealed devices showed better electrical characteristics than the N-2-annealed samples. Under O-2-annealing, field effect mobility was enhanced to 1.47 cm(2)/V s, the threshold voltage increased to -4.61 V and the subthreshold swing improved to 0.86 V/dec. Also, the transfer characteristics of a-IZO TFTs improve with annealing time. X-ray photoelectron spectroscopy (XPS) analysis indicated that the chemical composition of the IZO film was modified by the oxygen annealing.