H2O adsorption on amorphous In-Ga-Zn-O thin-film transistors under negative bias stress

Abstract

Amorphous In-Ga-Zn-O thin-film transistors on flexible substrates were prepared to investigate H2O adsorption under negative bias stress (NBS). Shorter channel lengths induce a more seriously deteriorated NBS stability due to the stronger electric field near the source or drain electrode. With increasing channel width, the NBS instability increases to a peak and then slightly decreases. Integrated Systems Engineering Technology Computer-aided Design (ISE-TCAD) simulation confirms that the electric field near the source/drain in the etch-stop layer is relatively dense, especially near the channel edges. The electric field direction is also confirmed to have significant effects on the H2O adsorption process.