Organic-transistor-based flexible pressure sensors using ink-jet-printed electrodes and gate dielectric layers

The authors have fabricated 33cm diagonal flexible pressure sensors using organic field-effect transistor (FET) active matrices. Polyimide precursors and silver nanoparticles are patterned on a polyimide film by using an ink-jet printing system and cured at 180°C to form gate dielectric layers and electrodes for organic FETs, respectively. In order to define the device dimensions, epoxy partitions are prepared by a screen printing system. The mobility of the transistors is 0.7cm2∕Vs and the on/off ratio exceeds 106. Spatial distributions of pressure are read out by an organic FET active matrix.