Photostable Zn2SnO4 Nanowire Transistors for Transparent Displays

Although oxide nanowires offer advantages for next-generation transparent display applications, they are also one of the most challenging materials for this purpose. Exposure of semiconducting channel areas of oxide nanowire transistors produces an undesirable increase in the photocurrent, which may result in unstable device operation. In this study, we have developed a Zn2SnO4 nanowire transistor that operates stably regardless of changes in the external illumination. In particular, after exposure to a light source of 2100 lx, the threshold voltage (Vth) showed a negative shift of less than 0.4 V, and the subthreshold slope (SS) changed by ∼0.1 V/dec. ZnO or SnO2 nanowire transistors, in contrast, showed 1.5–2.0 V negative shift in Vth and an SS change of ∼0.3 V/dec under the same conditions. Furthermore, the Zn2SnO4 nanowire transistors returned to their initial state immediately after the light source was turned off, unlike those using the other two nanowires. Thus, Zn2SnO4 nanowires achieve photostability without the application of a black material or additional processing, minimizing the photocurrent effect for display devices.