We demonstrate the growth of ultra-thin (~5 nm) indium ytterbium oxide (In-Yb-O) thin film using a simple vacuum-free aqueous solution approach for the first time. The influences of Yb addition on the microstructural, chemical, optical, and electrical properties of In2O3 are well investigated. The analyses indicate that Yb dopant could suppress oxygen vacancy defects effectively owing to the lower standard electrode potential, lower electronegativity, and stronger metal-oxide bond strength than that of In. The optimized In-Yb-O thin-film transistors (TFTs) exhibit excellent electrical performance (mobility of 8 cm2/Vs and on/off ratio of ~108) and enhanced stability. The triumph of In-Yb-O TFTs is owing to the high quality In2O3 matrix, the remarkable suppressor of Yb, and the nanometer-thin and atomically smooth nature (RMS: ~0.26 nm) of channel layer. Therefore, the eco-friendly water-induced ultra-thin In-Yb-O channel provides an excellent opportunity for future large-scale and cost-effective electronic applications.
Keywords: aqueous solution-processed; bias stress stability; indium ytterbium oxide; thin-film transistors; ultra-thin.