[18a-F104-1~12] 12.2 Characterization and Materials Physics

△ [18a-F104-10] Analyses of Interaction between Hole Carrier and Ionic Liquid at the Interface in Electric Double Layer Organic FET

〇Daijiro Okaue¹, Sakurako Ono¹, Kota Sakamoto¹, Hiroaki Nato¹, Taiki Sato¹, Ichiro Tanabe¹, Akihito Imanishi¹, Jun Takeya², Ken-ichi Fukui¹ (1.Osaka Univ., 2.The Univ. of Tokyo)

Keywords:surface, interface, organic FET, ionic liquid

We measured the time course of hole carrier mobility of electric double layer organic FETs with ionic liquid as insulator and rubrene single crystal as organic semiconductor. From the result, we made a model that anions of the ionic liquid strongly interact with hole carriers at the interface between the ionic liquid and the rubrene single crystal. To prove this model, we measured the time course of capacitance which is due to anions and hole carriers at the interface. The interfacial capacitance also increased when the hole mobility also increased. In usual, the interfacial capacitance is inversely proportional to the carrier mobility. This unusual trend is also consistent with the interaction model.