Vacuum relaxation and annealing-induced enhancement of mobility of regioregular poly(3-hexylthiophene) field-effect transistors

In order to enhance the performance of regioregular poly(3-hexylthiophene) (RR-P3HT) field-effect transistors (FETs),RR-P3HT FETs are prepared by the spin-coating method followed by vacuum placement and annealing.This paper reports that the crystal structure,the molecule interconnection,the surface morphology,and the charge carrier mobility of RR-P3HT films are affected by vacuum relaxation and annealing.The results reveal that the field-effect mobility of RR-P3HT FETs can reach 4.17 × 10 2 m2/(V · s) by vacuum relaxation at room temperature due to an enhanced local self-organization.Furthermore,it reports that an appropriate annealing temperature can facilitate the crystal structure,the orientation and the interconnection of polymer molecules.These results show that the field-effect mobility of device annealed at 150 C for 10 minutes in vacuum at atmosphere and followed by placement for 20 hours in vacuum at room temperature is enhanced dramatically to 9.00 × 10 2 cm2/(V · s).