PREDICTION OF CHARGE MOBILITY AND ITS TEMPERATURE-DEPENDENCE IN NEUTRAL POLY(3-HEXYLTHIOPHENE) FROM DIELECTRIC-RELAXATION MEASUREMENT

For neutral poly(3-hexylthiophene) (P3HT), the electric modulus formalism of dielectric relaxation measurement together with the use of non-exponential decay function can be applied to describe the behavior of conductivity relaxation. The charge mobility of neutral P3HT calculated from conductivity relaxation frequency with the use of the defect-diffusion model is in agreement with the data from field-effect transistor measurement. The temperature dependence of charge mobility exhibits a local maximum right after the end of glass transition region, which can be attributed to the transition of soft conformons in the disordered phase to localized conformons.