Fabrication and Characterization of p-type SnO Thin-Film Transistors by Reactive DC Magnetron Sputtering

In this study, the p-type SnO thin films were prepared on Si/SiO2 substrates by reactive DC magnetron sputtering and post-annealing treatment. We investigated the effects of annealing temperature on the electrical properties of the p-type SnO semiconductor thin films and thin-film transistors. XRD examination confirmed that these as-prepared SnO thin films were polycrystalline in nature and exhibited tetragonal SnO structure. The electrical resistivity of the annealed SnO thin films increased with raising annealing temperature because the reduction in the hole concentration. According to the transfer characteristics of the SnO TFTs, it was found that raising annealing temperature not only reduced the on current and off current but also leaded to the threshold voltage shifted towards negative voltage region. The TFT with a 200 °C annealed SnO active channel layer showed the highest on-to-off current ratio of 3.35×103, the smallest subthreshold swing of 10.0 V/dec, and a mobility of 1.65 cm2/Vs.