Volume 56 (2017) Issue 6 Pages 579-588
This article reports briefly on flexible and printed organic electronics, with an emphasis on organic thin-film transistor (OTFT) device technology, and highlights our laboratory's latest research and development results. Progress will be described in areas including printing processes, printable materials and printed devices, as well as potential applications. Printed OTFT devices are fabricated with various printing methods and silver nanoparticle inks are commonly used to form interconnects and electrodes. Small-molecule organic semiconductors with their highly crystalline nature are patterned on printed source and drain electrodes. A typical carrier mobility for printed OTFT devices is over 1cm2/Vs at low operating voltages, even for short channel length devices. Integrated circuits such as D-flip flops and ring oscillators as well as operational amplifiers are successfully demonstrated. An OTFT-based biosensor with an extended gate electrode for bio-sensing is proposed and good sensitivities are obtained for the detection of immunoglobulins, lactate and other biomarkers. Lastly, flexible hybrid sensors with Si-LSI die are also demonstrated and their applications are discussed.