64‐4: Manufacturing and Encapsulation Process of Bottom Gate Bottom Contact Thin‐Film Transistors with a Printed Oxide Semiconductor

Abstract

We present bottom gate bottom contact staggered oxide semiconductor TFTs, manufactured by using an ink-jet printed metal oxide semi-conductor material from the company Evonik. The printed TFTs with optimized process and adjusted channel geometry present high charge carrier mobility values between 10 and 15 cm 2 /V . s and on/off current-ratios of more than 10 6 . The maximum temperature used is 300 °C, which makes the process compatible with the display manufacturing. To achieve a more stable electric behavior and better threshold voltage homogeneity, mainly in the case of positive gate bias stress, we used a solution processed encapsulation to shield the device from the atmospheric effects. The encapsulated TFTs show a considerable stability improvement and present hence an attractive technology alternative for active matrix processes.