ZnO/MgO/ITO structured thin film transistor for ultraviolet photo detector application

ZnO based thin-film transistors have been fabricated by means of the gate dielectric of MgO using E beam deposition. In this work MgO and ZnO, bilayer of 150 nm each have been deposited on ITO glass substrate. MgO layer is supportive to reducing the gate leakage current due to a large band equalize the ZnO channel layer, and to attain high transparency in the visible light band due to a broad bandgap of 7.8 eV. The obtained UV Photodetector gives outstanding UV sensing properties. The improvement of the photoresponsivity of the ZnO UV detector was carried out by the surface treatment of the ZnO thin film. The results show a great extent facilitates the fabrication of significant metal-insulator-semiconductor at low cost and low temperatures and high improvements in the detector performance. The achieved field-effect mobility is 2.70 cm2 V−1 s−1 and on/off current ratio is around 1 × 104 which shows the ZnO-TFTs work in enhancement mode. The threshold voltage is achieved as 5.1 V. The electrical results of ZnO/MgO-TFTs are predictable to get better additional by optimizing expansion circumstances.