Low-temperature soluble InZnO thin film transistors by microwave annealing

Low-temperature solution-deposited thin film transistors (TFTs) involving sol–gel derived indium zinc oxide (IZO) as active layers is reported. Microwave annealing is shown to afford the fabrication of low-temperature processable TFTs. Solution-processed IZO-TFTs prepared at 150 °C by microwave irradiation have shown enhanced device characteristics of 0.1 cm2 V−1 s−1 mobility and a ∼106 on/off current ratio, a threshold voltage of 8.1, and a subthreshold slope of 3.3 V/decade. From the results of X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM), we confirmed that the device improvement originates from better crystallization at low temperature made possible by the use of microwave irradiation. Our findings suggest that solution-processable oxide semiconductors have potential for low-temperature and high-performance applications in transparent flexible devices.