Change of molecular ordering in soluble acenes via solvent annealing and its effect on field-effect mobility

The increase of the molecular ordering and field-effect mobility in triethylsilylethynyl anthradithiophene (TES ADT) thin film transistors by solvent annealing was investigated. X-ray diffraction data revealed that TES ADT molecules crystallize with silyl groups on the substrate surface. After solvent annealing, spherulites were formed and the field-effect mobilities dramatically increased up to 0.43cm2∕Vs (over 100-fold) as result of maximized overlap of π electron clouds along the in-plane direction and the formation of a continuous crystal.