Solgel processed oxide thin-film transistors with mobility up to 30cm2/Vs

Methods to fabricate uniform, high-mobility thin-film transistors are highly desirable, because they will lead to enhanced performance in large-area displays and sensors. Amorphous oxide semiconductors have shown promising performance with good uniformity over large-area, and here we fabricated thin-film transistors from solution processing of solgel oxide precursors based on In-Ga-Zn nitrates. The transistor characteristics were examined over a wide range of precursor composition and processing variables. The TFT mobility, threshold voltage, and bias stress properties were compared. Upon optimization, we have achieved transistor mobility up to 30cm2/Vs for IZO annealed at 400 degrees C, and the transistor current changed less than 10% under positive bias stress for one hour. The current limiting factor of this transistor technology is the stress effect under light illumination with negative bias. We will discuss our preliminary findings and strategies to address this bottleneck.