200-V ITO Thin-Film Transistors with the Stair-ITO Drift Region

In this work, a 200-V indium tin oxide (ITO) thin-film transistor (TFT) with a stair drift region was demonstrated for the first time. The proposed high voltage (HV) ITO TFT has the channel region of a 4-nm thick ITO and the stair drift region of a 14-nm thick ITO. The stair ITO of the drift region help to lower the electric field under the high operation voltage, increasing the breakdown voltage (V
BD
) to 200 V. Meanwhile, the proposed HV TFT owns a small on-resistance (R
on
) because the 14-nm thick ITO has the minimum resistance. The drift region contributes only 10% of the total R
on
, which is confirmed by the gate-four-probe (GFP) measurement.