DETERMINATION OF THERMAL PARAMETERS AND THE OPTICAL GAP OF POLY(3-BUTYLTHIOPHENE) FILMS BY PHOTOPYROELECTRIC SPECTROSCOPY

Thermal parameters and the optical gap of undoped poly(3-butylthiophen e) films were determined by photopyroelectric spectroscopy, using a PV DF film as the pyroelectric detector. The band gap energy was determin ed using both the amplitude and the phase curves for different choppin g frequencies. When the theoretical model developed by Mandelis and Zv er [J. Appl. Phys. 57, 4421 (1985)], was applied to the experimental r esults comprising amplitude and phase difference spectra, the thermal diffusivity and the thermal conductivity were obtained as fitting para meters.