Fully Solution-Processed Sodium Doped ZnO Thin-Film Transistors via a Low-Temperature Aqueous Route

In this study, we develop a simple and eco-friendly aqueous route for the fabrication of sodium (Na) doped ZnO/AlOx thin-film transistors (TFTs). To prepare Na doped ZnO and AlOx thin films, ammonia water and deionized water were used as the precursor solvents. The AlOx thin film annealed at 300 degrees C showed an areal-capacitance of 129 nF/cm(2) at 1 kHz. On the basis of its implementation as the gate oxide, fully solution-processed Na doped ZnO TFTs were fabricated and the electrical characteristics were systematically studied. The fully solution processed Na doped ZnO/AlOx TFTs exhibited a high field effect mobility of 21 cm(2)V(-1)s(-1), a subthreshold swing of 0.58 V/decade, a threshold voltage of 0.8 V, and an on/off current ratio of 2x10(4).