Low-Temperature, Nontoxic Water-Induced Metal-Oxide Thin Films and Their Application in Thin-Film Transistors

Here, a simple, nontoxic, and inexpensive water-inducement technique for the fabrication of oxide thin films at low annealing temperatures is reported. For water-induced (WI) precursor solution, the solvent is composed of water without additional organic additives and catalysts. The thermogravimetric analysis indicates that the annealing temperature can be lowered by prolonging the annealing time. A systematic study is carried out to reveal the annealing condition dependence on the performance of the thin-film transistors (TFTs). The WI indium-zinc oxide (IZO) TFT integrated on SiO2 dielectric, annealed at 300 degrees C for 2 h, exhibits a saturation mobility of 3.35 cm(2) V-1 s(-1) and an on-to-off current ratio of approximate to 10(8). Interestingly, through prolonging the annealing time to 4 h, the electrical parameters of IZO TFTs annealed at 230 degrees C are comparable with the TFTs annealed at 300 degrees C. Finally, fully WI IZO TFT based on YOx dielectric is integrated and investigated. This TFT device can be regarded as green electronics in a true sense, because no organic-related additives are used during the whole device fabrication process. The as-fabricated IZO/YOx TFT exhibits excellent electron transport characteristics with low operating voltage (approximate to 1.5 V), small subthreshold swing voltage of 65 mV dec(-1) and the mobility in excess of 25 cm(2) V-1 s(-1).