Physical/chemical characterization of amorphous indium-gallium-zinc-oxynitride thin film transistors

Abstract

Amorphous In-Ga-Zn-O experiences device instability in thin-film transistors (TFTs) due to the vulnerability of oxide channel materials under ambient conditions. Nitrogenation of In-Ga-Zn-O TFTs by partial oxygen substation of nitrogen was performed to enhance stability. The nitrogenated In-Ga-Zn-O thin films were deposited under plasma conditions involving nitrogen gas molecules. The TFT stability was tested under various conditions of temperature, illumination, time, and sweeping. Despite the minor weakness at elevated operation temperature, the nitrogenated In-Ga-Zn-O TFTs exhibited superior tolerance against sweeping operations in TFT devices, illumination, and time-dependent degradation. The improved stability is attributed to the incorporation of nitrogen into ln-Ga-Zn-O via oxygen vacancy and its corresponding interface trap improvement.