N2O Plasma Treatment Suppressed Temperature-dependent Point Defects Formation with Amorphous Indium-Gallium-Zinc-Oxide Thin Film Transistors

摘要

The abnormal sub-threshold leakage current is observed at high temperature in amorphous Indium-Gallium-Zinc-Oxide Thin Film Transistors (a-IGZO TFTs). This phenomenon depends on the defects of a-IGZO active layer of the device, which is treated by N2O plasma. This phenomenon only appears in the as-fabricated device, but not in the device with N2O plasma treatment, which is experimentally verified. N2O plasma treatment enhances the thin film bonding strength which could suppress the formation of temperature-dependent hole. The hole can be generated from oxygen atoms above 400K by leaving their original sites. The N2O plasma treatment devices have better stability performance than as-fabricated devices. The results suggest that the density of defects for a-IGZO TFTs with N2O plasma treatment is much lower than that as-fabricated. The N2O plasma treatment repairs the defects and suppresses temperature-dependent sub-threshold leakage current.