Fabrication and testing of pentacene thin-film transistors that use water-dispersible polyaniline electrodes

Polyaniline (PANI) - in its conductive form - is an attractive candidate for organic and polymer electronics because of its chemical and environmental stability. Due to the difficulties associated with materials processing, however, fabricating PANI electronic components has been challenging. In this paper, we report a simple, low-cost technique for patterning water-dispersible, conductive PANI. Unlike previous techniques, where the polyaniline has to be doped post-processing to render electrical conductivity, our patterning scheme uses predoped aqueous solutions of PANI. Our technique relies on specific interactions between doped PANI and the substrate; patterns as small as 20 μm can be routinely fabricated. To demonstrate patterning versatility, we fabricated and tested pentacene thin-film transistors (TFTs) that use PANI source and drain electrodes.