The small signal model was

The Ge–IZO TFTs were fabricated with a bottom-gate-inverted structure on heavily doped n-type Si substrates with 150-nm-thick silicon dioxide, where the Si substrate was used as a gate electrode and silicon dioxide was used as a gate insulator.
3. Results and discussion
The output-characteristic curves of the three different Ge–IZO TFTs AZD4547 shown in Fig. 2(a). When we perform the measurement, we sweep the drain voltage (VD) from 0 to 20 V, with a fixed 5 V gate voltage (VG). By using the buffer layer (IZO) in IZO/Ge–IZO and Ge–IZO/IZO channel structures, the saturation current easily exceeded 100 μA at a relatively low VG, indicating dermal system the TFTs have high mobility and good driving performance.
Fig. 2. (a) Output-characteristic curves of the TFTs (VD was changed from 0 to 20 V and VG was fixed 5 V); (b) transfer-characteristic curves of the TFTs (VD was fixed at 20 V and VG was changed from −40 to 40 V) to demonstrate the electrical characteristics using IZO buffer layer.Figure optionsDownload full-size imageDownload as PowerPoint slide