We demonstrate ultrathin, ultraflexible, large-area pressure sensors based on an organic transistor integrated circuit. A 10-μm-thick plastic film with an organic transistor active matrix is developed that can be bent to a bending radius of less than 1 mm to create an electrical artificial skin (E-skin). The thin-film, flexible pressure-sensor matrix is implemented on a curved surface, and the spatial distribution of pressure is successfully obtained in real time.

Flexible electronics have attracted much attention since they enable promising applications such as low-cost RFID tags and e-paper. Thin-film transistors (TFTs) are considered as an ideal candidate to implement flexible electronics on low-cost substrates. Most TFT technologies, however, have only mono-type - either n- or p-type - devices and thus modern design technologies for silicon-based electronics cannot be directly applied. In this paper, we propose a novel design style Pseudo-CMOS for flexible electronics that uses only mono-type TFTs while achieving comparable performance with the complementary-type designs. The manufacturing cost and complexity can therefore be significantly reduced while the circuit yield and reliability are also enhanced with the built-in capability of post-fabrication tuning. Some standard cells have been designed and fabricated in p-type organic and n-type InGaZnO (IGZO) TFT technologies which successfully verify the superiority of the proposed Pseudo-CMOS design style. To the best of our knowledge, this is the first design solution that has proven superior performance for both types of TFT technologies.

Organic electronics is attracting a lot of attention for large-area pervasive electronics applications, because organic transistors can be fabricated using printing technologies on arbitrary substrates and this enables both high-throughput and low-cost production. In this paper, some examples of the large area electronics with the organic transistors including a wireless power transmission sheet and a communication sheet are presented. Challenges for future large area electronics are also described.