Low power consumption is essential for wearable and internet-of-things applications. An effective way of reducing power consumption is to reduce the operation voltage using a very thin and high-dielectric gate insulator. In an oxide thin-film transistor (TFT), the channel layer is an oxide material in which oxygen reacts with metal to form a thin insulator layer. The interfacial oxidation between the gate metal and In–Ga–Zn oxide (IGZO) was investigated with Al, Ti, and Mo. Positive bias was applied to the gate metal for enhanced oxygen diffusion since the migration of oxygen is an important factor in interfacial oxidation. Through interfacial oxidation, a top-gate oxide TFT was developed with low source–drain voltages below 0.5 V and a gate voltage swing less than 1 V, which provide low power consumption.

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Low voltage oxide thin-lm transistors (TFTs) operating below 1.0 V were developed using a high dielectric constant tantalum oxide produced by thermal oxidation. Thermal oxidation was carried out at 400, 500, and 600 °C under an oxygen atmosphere. The tantalum oxide was evaluated by X-ray photoelectron spectroscopy (XPS). XPS con rmed the binding energy of Ta4f, indicating the binding state of tantalum oxide. The bottom gate oxide TFT with the gate insulator of tantalum oxide grown at 500 °C exhibited mobility of 12.61 cm2/V and a threshold voltage of 0.46 V. The transfer characteristics at the drain voltages below 1.0 V show its applicability to low voltage operation below 1 V. The bootstrapped inverter with developed oxide TFTs operated well at the operation voltages of both the 1.0 and 2.0 V.

AMOLED pixel circuit was proposed to compensate for reduced luminance by both the stretching and IR drop on power line. In addition, the proposed circuit keeps compensation function for both the positive and negative shift. The proposed circuit was verified by the simulation for the negative shift of threshold voltages, IR drop at power bus line and the stretching induced luminance change.

Low voltage oxide thin-film transistors (TFTs) operating below 1.0 V were developed using a high dielectric constant tantalum oxide produced by thermal oxidation. Thermal oxidation was carried out at 400, 500, and 600 °C under an oxygen atmosphere. The tantalum oxide was evaluated by X-ray photoelectron spectroscopy (XPS). XPS confirmed the binding energy of Ta4f, indicating the binding state of tantalum oxide. The bottom gate oxide TFT with the gate insulator of tantalum oxide grown at 500 °C exhibited mobility of 12.61 cm2/V and a threshold voltage of 0.46 V. The transfer characteristics at the drain voltages below 1.0 V show its applicability to low voltage operation below 1 V. The bootstrapped inverter with developed oxide TFTs operated well at the operation voltages of both the 1.0 and 2.0 V.