UV-Ozone Process for Film Densification of Solution-Processed InGaZnO Thin-Film Transistors

The effects of ultraviolet (UV)-ozone treatment on solution-processed amorphous InGaZnO (IGZO) thin-film transistors (TFTs) grown using the sol-gel method are investigated. The UV-ozone-treated TFT devices showed an improved field-effect mobility of 1.52 cm
²
·V
^-1
·s
^-1
and a subthreshold slope (S) of 0.42 V/dec compared to those of IGZO TFT devices with only thermal annealing (0.75 cm
²
·V
^-1
·s
^-1
and 0.84 V/dec, respectively). The enhancement of the UV-ozone-treated TFTs is mostly attributed to the increased film packing density, higher Al S/D electrodes adhesion properties, reduced oxygen-related defects, and less electron trapping of the IGZO thin films, which improved the TFT performance and bias stress stability.