Pentacene thin films obtained by thermal evaporation at room temperature have been incorporated as the active layer in bottom-gate thin-film transistors (TFTs). The dielectric was spin-cast polymethyl methacrylate (PMMA) baked at only 170 °C. Crystalline silicon wafers and polyethylenenaphtalate (PEN) polymer foils were used as substrates. These devices were electrically characterised by measuring the output and transfer characteristics at different temperatures. Both the channel conductance and field-effect mobility evidenced similar thermal activation energies around 0.15 eV. These results could indicate that electrical transport is mainly controlled by trapping and thermal release of carriers from localised states.

Peer Reviewed