Amorphous In-Ga-Zn-O Thin-Film Transistor for High Resolution Active Matrix Flat Panel Displays and Imagers.

[摘要] There is considerable interest in adapting amorphous Indium-Gallium-Zinc-Oxide thin-film transistors (a-IGZO TFTs) in such applications as active matrix flat panel displays (AM-FPDs) and imagers (AM-FPIs), because of their high mobility in the amorphous phase, low off-current and suitability for low temperature fabrication. So far much of the research efforts on a-IGZO TFTs have been focused on improving the a-IGZO material properties as well as the gate dielectric/a-IGZO interface.However, the electrical performance of TFTs is also influenced by the TFT structures. In this study, the characteristics of the double gate (DG) coplanar homojunction a-IGZO TFTs are investigated. The coplanar homojunction a-IGZO TFT has a good ohmic source/drain junction. With DG structure, a high on-current and steep subthreshold swing are achieved without any changes in the off-current by applying the same voltage on the bottom and top gates. The dynamic control of TFT;;s threshold voltage is also demonstrated by applying various voltages on the top gate. To explain these phenomena, analytic models of DG a-IGZO TFTs are developed based on device physics. Furthermore, this study shows that the illumination and bias-temperature stabilities are enhanced in comparison to traditional single gate a-IGZO TFTs. The superior electrical properties and stability of the DG a-IGZO TFT make it possible strong candidates for use in pixel circuits of future high resolution AM-FPDs and AM-FPIs.

[发布机构] University of Michigan

[效力级别] Amorphous

[关键词] Thin-film Transistor;Amorphous;Indium Gallium Zinc Oxide;Double Gate;Electrical Engineering;Engineering;Electrical Engineering