P‐11: Carrier Concentration Reduction by Fluorine Doping in P‐Type SnO Thin‐Film Transistors

Presently reported is the use of plasma fluorination treatment based on tetrafluoromethane to enhance the performance of a p‐type SnO thin‐film transistor (TFT). The improved performance metrics include a larger on/off current ratio, a smaller subthreshold swing and a reduction of an originally large positive turn‐on voltage. The effects of such fluorination treatment were also investigated using a host of thin‐film characterization techniques and their origin most plausibly attributed to both the significant reduction of the carrier concentration from ~2 × 10 19 cm −3 to ~4.3 × 10 16 cm −3 and the passivation of the defects. It is demonstrated that fluorination is an effective technique for making higher performance p‐type metal‐oxide TFTs.