Fabrication of solution-processed amorphous indium zinc oxide thin-film transistors at low temperatures using deep-UV irradiation under wet conditions

We fabricated solution-processed indium zinc oxide (IZO) thin film transistors (TFTs) at annealing temperatures as low as 250 °C using deep UV (DUV) irradiation in water vapor medium. The DUV light decomposed the carbon compounds in the IZO films, and the hydroxyl radicals generated when water vapor reacted with ozone effectively oxidized the films. These phenomena were confirmed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Finally, we fabricated DUV-treated IZO TFTs in water–vapor medium at 250 °C with a mobility of 1.2 cm2/Vs and an on/off current ratio of 2.66 × 106.