Development of inkjet printed N-type organic field-effect transistor with morphology control of insulating layer

Inkjet which enables drop on demand printing offers the advantage of material deposition at the desired location, reducing material consumption compared to lithographic process. This exciting feature will enhance the fabrication of organic electronic devices on wide and flexible substrate. For better performance of flexible circuits, CMOS electronic is necessary. Since N-channel organic field effect transistors (OFETs) are still not enough for the application to circuits, the development of N-channel OFET is necessary. Inkjet printed N-channel OFETs were developed using epoxy based ink as a gate insulator. Results obtained in this study shows that printed epoxy film can be used as a gate insulator of N-channel OFETs. The electrical performances were similar to those obtained with inorganic gate insulator. The stability was as good as only 7% decrease of drain current after 10 minutes under operation condition. The study presents the possibility of all printed OFETs CMOS circuits.