Low Voltage a-IGZO Thin Film Transistor Using Tantalum Oxide by Thermal Oxidation

다국어 초록 (Multilingual Abstract)

Low voltage oxide thin-fi lm transistors (TFTs) operating below 1.0 V were developed using a high dielectric constanttantalum oxide produced by thermal oxidation. Thermal oxidation was carried out at 400, 500 and 600 °C under an oxygenatmosphere. The tantalum oxide was evaluated by X-ray photoelectron spectroscopy (XPS). XPS confi rmed the bindingenergy of Ta4f, indicating the binding state of tantalum oxide. The bottom gate oxide TFT with the gate insulator of tantalumoxide grown at 500 °C exhibited mobility of 26.7 cm 2 /V s and a threshold voltage of 1.3 V. The transfer characteristics atthe drain voltages below 1.0 V show its applicability to low voltage operation below 1 V. The bootstrapped inverter withdeveloped oxide TFTs operated well at the 1.0 and 2.0 V operation voltages.