Effect of oxygen on the threshold voltage of a-IGZO TFT

Abstract

Thin-film transistors (TFTs) are fabricated using an amorphous indium gallium zinc oxide (a-IGZO) channel layer by rf-magnetron sputtering. Oxygen partial pressure significantly changed the transfer characteristics of a-IGZO TFTs. Measurements performed on а-IGZO TFT show the change of threshold voltage in the transistor channel layer and electrical properties with varying O2 ratios. The device performance is significantly affected by adjusting the O2 ratio. This ratio is closely related with the modulation generation by reducing the localized trapping carriers and defect centers at the interface or in the channel layer.