Synthesis, characterization and field-effect transistor performance of poly[2,6-bis(3-alkylthiophen-2-yl)benzo[1,2-b;4,5-b']diselenophene]s

Benzo[1,2-b:4,5-b']diselenophene (BDS) has been incorporated for the first time in a polymer. bis(Stannyl)-functionalized BDS was copolymerized with 3,3'-bis(alkyl)-5,5'-bithiophenes (dodecyl and tetradecyl side chains) through Stille copolymerization, to yield p-type polymer semiconductors for organic field-effect transistor application. The electronic and structural effect of the selenium atoms, compared to sulphur atoms in analogous copolymers, is described. The molecular weight has a decisive influence on the photophysical properties and supramolecular ordering, expressed in field-effect transistor measurements. Saturation mobilities around 10-2cm2• V-1s-1 are obtained on standard silicon substrates. Benzo[1,2-b:4,5-b']diselenophene-based copolymers have been synthesized by Stille copolymerization. The effect of the selenium atoms and the molecular weight on physical properties and field-effect transistor performance is discussed.