Dual Gate Indium–Zinc Oxide Thin-Film Transistors Based on Anodic Aluminum Oxide Gate Dielectrics

In this paper, we propose a dual gate thin-film transistor (TFT) based on anodic aluminum oxide gate dielectrics and investigate the top gate (TG) effect on device performance. It is shown that the threshold voltage of TFTs could been linearly modulated with respect to the applied TG voltage due to the modification of vertical electric field distribution between the bottom gate and top gate. In addition, the introduction of top gate would lead to the asymmetric control of threshold voltage modulation by the variation of bottom gate-dielectric and TG-dielectric, which makes it attractive in the TFT fabrication for intensive use. Moreover, the additional TG can provide an effective light shielding that guarantee the electrical reliability of TFTs under negative bias illumination stress with only -0.37 V shift of threshold voltage after 9000 s. Owning to its linear controllability of threshold voltage, it is believed that the dual-gate structure will be tentatively introduced in the application of compensation pixel circuit.