Solution deposited liquid crystalline semiconductors on a photoalignment layer for organic thin-film transistors

Abstract

Highly ordered liquid crystalline semiconductors on a light induced alignment layer results in an anisotropic electrical characteristic and an enhanced mobility of solution processed thin-film transistors. In the case of poly-9,9′-dioctyl-fluorene-co-bithiophene, a mobility as high as 0.02cm2V−1s−1 has been achieved by aligning a polymer chain parallel to the charge transport direction. Using an oligomeric semiconductor, 5,5′-bis(4-octyloxyphenyl)bithiophene, an enhanced mobility of 0.05cm2V−1s−1 was obtained by the alignment of the π-π intermolecular packing direction parallel to the charge transport direction.