摘要
We have successfully synthesized and characterized newly synthesized oxygen-heterocyclic and π-conjugated dimers, 9,9′-bi(benzo[b]naphtha[2,1-d]furan) (9-BBR), as a potential semiconductor material with good environmental stability for organic field-effect transistor (OFET) devices. As expected from DFT calculations, spectroscopic analyses allow us to confirm the compound has lower highest occupied molecular orbital (HOMO) energy level and larger HOMO-lowest unoccupied molecular orbital (LUMO) gap than those of pentacene. Absorption spectra of 9-BBR in an air-saturated solution remain unchanged, indicating substantial environmental stability; in fact, the mobility values of 9-BBR-based OFET devices are stable even in the presence of air. Maximum field-effect mobilities up to 10-2 cm2 V-1 s-1 are obtained by 9-BBR-based OFETs with hexamethyldisilazane (HMDS)-treated substrates at Tsub = 100 °C. X-ray diffraction and atomic force microscopy allow us to conclude that better characteristics of 9-BBR-based OFETs prepared at high Tsub are attributed to good crystallinity and large-sized grain morphology in the thin films.
