[19a-P4-1~31] 12.4 Organic light-emitting devices and organic transistors

[19a-P4-1] Organic CMOS Inverters Using n-Type Transistor Materials Containing Carbonyl-Bridged Bithiazole Unit

〇Masashi Nitani¹, Yutaka Ie¹, Cedric Rolin², Paul Heremans², Yoshio Aso¹ (1.ISIR Osaka univ., 2.imec)

Keywords:Organic semiconductor,CMOS inverter,n-Type

A great deal of efforts has been devoted to developing new p-conjugated systems as materials for organic field-effect transistors (OFETs) and their CMOS inverters for future applications. However, n-type semiconducting materials are still required to develop because of their lower performances and less stability under ambient air driving compare to p-type materials. From this point of view, electronegative compounds have attracted much attention because of their potential for n-type OFET materials. Recently, we have developed carbonyl-bridged bithiazole as an electronegative unit and its based compound. The carbonyl-bridging contributes to both decreasing the LUMO energy level and keeping a coplanar geometry. Their devices fabricated by vacuum-deposition technique showed n-type characteristics with field-effect electron mobility of 0.06 cm² V^–1 s^–1 and stable operation under air. In this study, we have fabricated and evaluated organic CMOS inverters consist of our n-type semiconductor having carbonyl-bridging. CMOS inverters were fabricated by vacuum-deposition of our n-type material and DNTT as p-type material. They showed clear inverter characteristics and higher gain of over 100. As compare to non-carbonyl-bridging materials, their devices possess smaller hysteresis and lower threshold voltage.