Developments of high precision printing processes for fabricating the flexible electronics

For the fabrication of an organic thin film transistor (OTFT) array on a plastic film using printing techniques, fine patterns with widths less than 10 μm were required. We have already succeeded to fabricate the OTFT arrays on a film substrate using microcontact printing and reverse-offset printing of silver nanoparticle ink; a width of the source and drain electrodes of the OTFT fabricated reached 5 μm, and its channel distance was also 5 μm. In this report, we introduce and explain our newly developed printing techniques based on microcontact printing, to obtain fine, high precision, and thick patterns for the manufacturing of the practical printed and flexible electronic devices.