Fabrication of a field effect transistor structure using charge-ordered organic materials α-(BEDT-TTF)2I3 and α′-(BEDT-TTF)2IBr2

The effect of electrostatic charge carrier injection into the charge-ordered (CO) organic materials [α-(BEDT-TTF)2I3 and α′-(BEDT-TTF)2IBr2] using a field effect transistor (FET) structure is investigated. Depending on the devices, both n-type and p-type behaviors are observed. Our results reveal that only the hole transfer property is strongly affected by the interface conditions of the devices. In addition, our devices presently show relatively low gate response compared to the recently reported organic Mott FET. This result suggests that a gate-induced drastic change of electronic state, which is proposed in the organic Mott FET, is not observed in the present CO FET.