Low-Voltage-Operating Transistors and Logic Circuits Based on a Water-Driven ZrGdO_x Dielectric with Low-Cost ZnSnO

In current work, the nontoxic, ecofriendly, water-induced (WI) gadolinium doped zirconium oxide (ZrGdOx) gate dielectrics have been integrated with low-cost spin-coating-driven ZnSnO films for thin film transistors (TFTs) and logic circuits with superior performance for the first time. High transmittance over 90% and the formation of the metastable cubic phase of Zr2O have qualified its potential application in transparent electronics. ZnSnO films annealed at 430 °C integrated with ZrGdOx films demonstrate remarkable electrical properties and low-voltage operation (2 V), including a high current on/off ratio of ∼1.1 × 106, large saturation carrier mobility of ∼3.1 cm2 V–1 S–1, extreme low leakage current density of 6 × 10–10 A cm–2, and a slight shift in threshold voltage of 0.26 V for bias stability, respectively. To verify the practicability in logic circuits, the resistor-loaded inverters are built by using ZrGdOx/ZnSnO TFTs. This work first put forward and verified that WI gate dielectrics can be favorable to a heterogeneous clean interface with a solution-derived ZnSnO channel layer, taking an important step toward a low-operating voltage and ecofriendly flexible integrated circuit.