Observation of field-effect in a cross-linked polyfluorene semiconductor

A cross-linkable semiconducting polyfluorene was synthesised and used, in the cross-linked, insoluble form, in the fabrication of field-effect transistors, FETs. This photopatternable polymer derives from the well known poly(9,9-dioctylfluorene-alt-bithiophene), F8T2, which is one of the most studied semiconductors for FETs. We find that FETs using this cross-linked polyfluorene semiconductor show p-type behaviour with mobility 8.3 × 10−5 cm2/V s. Although this value is one order of magnitude smaller than that found for similarly prepared F8T2-based FETs (6.8 × 10−4 cm2/V s), and which we mainly attribute to disorder, the use of this type of polymer opens new perspectives in terms of device fabrication.