Low-Temperature, aqueous-solution-processed zinc tin oxide thin film transistor

We fabricate solution-processed zinc tin oxide (ZTO) thin-film transistors (TFTs). The solution used is prepared by precipitating metal hydroxide using NaOH and dissolving it using NH₄OH. The X-ray diffraction (XRD) data of the spin-coated ZTO film demonstrates an amorphous phase, and the atomic force microscopy (AFM) image shows a smooth surface. The device performance of solution-processed TFTs was analyzed as a function of annealing temperature. The fabricated TFTs were operated in the enhancement mode, and exhibited a carrier mobility of 3.03 cm² V^-1 s^-1, a threshold voltage of 10.2 V, an on/off current ratio of 1.23 × 10⁷, a subthreshold slope of 0.78 V/decade, and high transparency (with ∼ransmittance) at a low annealing temperature of 300 °C.