High-performance low-temperature solution-processable ZnO thin film transistors by microwave-assisted annealing

Oxide semiconductors afford a promising alternative to organic semiconductors and amorphous silicon materials in applications requiring transparent thin film transistors (TFTs). We synthesized an aqueous inorganic precursor by a direct dissolution of zinc hydroxide in ammonium hydroxide solution from which a dense and uniform ZnO semiconducting layer is achieved. Solution-processed ZnO-TFTs prepared at 140 degrees C by microwave irradiation have shown enhanced device characteristics of similar to 1.7 cm(2) V(-1)s(-1) mobility and a similar to 10(7) on/off current ratio, with good air stability. Spectroscopic analyses confirmed that such a device improvement originates from accelerated dehydroxylation and better crystallization at low temperature by microwave irradiation. Our results suggest that solution-processable oxide semiconductors have potential for low-temperature and high-performance applications in transparent devices.