Thermal annealing-induced enhancement of the field-effect mobility of regioregular poly(3-hexylthiophene) films

Polymer field-effect transistors with a field-effect mobility of µ˜0.3 cm2 s-1 V-1 have been demonstrated using regioregular poly(3-hexylthiophene) (rr-P3HT). Devices were fabricated by dip coating the semiconducting polymer followed by annealing at 150 °C for 10 min. The heat annealed devices exhibit an increased field-effect mobility compared with the as-prepared devices. Morphology studies and analysis of the channel resistance demonstrate that the annealing process increases the crystallinity of rr-P3HT and improves the contact between the electrodes and the P3HT films, thereby increasing the field-effect mobility of the films.