Fast Low-Temperature Plasma Process for the Application of Flexible Tin-Oxide-Channel Thin Film Transistors

In this study, we demonstrated a p -type and n -type SnO TFTs on flexible polyimide substrate. The fabricated p -type SnO TFT showed a high $I_{\rm on}/ I_{\rm off}$ of $ \text{5.7}\, \times \,\text{10}⁵$ and a high $\mu _{{\rm{FE}}}$ of ${\text{10.7 cm}}²\,{\text{V}}^-1\,{\text{s}}^-1$ . Through optimizing the oxygen plasma condition, the n -type channel TFT transfered from prime p -type channel exhibits excellent characteristics, including a high on/off current ratio of $\rm{6.6}\,\times\,10³$ , a low threshold voltage of −0.13 V, and a very high field-effect mobility of ${\text{28 cm}}²\,{\text{V}}^-1\,{\text{s}}^-1$ . This proposed low-temperature oxygen plasma treatment shows the potential in simplification of TFT process that can achieve n -type and p -type TFTs under the same device process.