  We report on the simple fabrication of hysteresis-free and electrically
stable organic field-effect transistors (OFETs) and inverters operating at
voltages <1-2 V, enabled by the almost trap-free interface between the organic
semiconductor and an ultra-thin (<20 nm) and highly insulating single-layer
fluoropolymer gate dielectric (Cytop). OFETs with PTCDI-C13
(N,N'-ditridecylperylene-3,4,9,10-tetracarboxylicdiimide) as semiconductor
exhibit outstanding transistor characteristics: very low threshold voltage
(0.2V), onset at 0V, steep subthreshold swing (0.1-0.2 V/decade), no hysteresis
and excellent stability against gate bias stress. It is gratifying to notice
that such small OFET operating voltages can be achieved with the relatively
simple processing techniques employed in this study.
