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 a-IGZO TFT show the change of threshold voltage in the transistor channel layer and electrical properties with varying O-2 ratios. The device performance is significantly affected by adjusting the O-2 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.