Solution-Processed Zinc Oxide Thin-Film Transistors With a Low-Temperature Polymer Passivation Layer

Bottom-gate top-contact zinc oxide (ZnO) thin-film transistors were fabricated with a low annealing temperature (150 °C) using ammine-hydroxo zinc precursors. The unpassivated devices present profound hysteresis in the measured current-voltage characteristics and a negative output conductance, which were attributed to the interaction of back surface with the oxygen molecules in the ambient atmosphere. To suppress the ambient influence without impacting the device´s intrinsic performance, a simple low-temperature (75 °C ) solution-based passivation approach with polydimethylsiloxane was developed. The passivated devices present typical field-effect transistor behaviors of greatly improved device performance.