Organic single-crystal transistors based on π-extended heteroheptacene microribbons

Facile synthesis of a new series of π-extended thienoacenes has been described. Their electronic structures have been elucidated by UVvis absorption and photoelectron spectra. Well-defined single-crystal microribbons composed of self-organized thienoacene molecules have been fabricated using physical vapor transport, and have been applied to field-effect transistors. The organic transistors employing the single-crystal microribbons exhibit mobilities as high as 0.47 cm²Vs^-1 with on/off ratios of ca. 10⁶.