Design and fabrication of ZnO/TiO2-based thin-film inverter circuits using solution processing techniques

Novel and cost-effective ceramic-based thin-film inverter circuits, based on two layers of TiO2 and ZnO films to construct junction field-effect transistors (FETs), were designed and fabricated by solution coating techniques. The double layers of the sol–gel ZnO and TiO2 films were coated and characterized as a diode according to the current–voltage performance. Two types of FETs, the p-channel (p-FET) and the n-channel (n-FET) devices, were produced using different coating sequences of ZnO and TiO2 layers. Both of the transistor performances were evaluated by analyzing the source–drain current versus voltage (Ids–Vds) data with the control of the gate voltage (Vg). The ZnO/TiO2-based inverter circuits, such as the complementary-FET device, were further fabricated using the integration of the p-FET and the n-FET. The voltage transfer characteristics of the inverters were estimated by the tests of the input voltage (Vin) versus the output voltage (Vout) for the thin-film inverter circuits. (paper)