Using the temperature dependence of the forward-biased current-voltage characteristics as well as capacitance-voltage measurements, we calculated the contact barrier height of the heterojunction between poly(dithienopyrrole)-poly(vinylchloride) composite and n Si. Analysis of the characteristics suggests that thermionic emission over the composite/inorganic contact barrier dominates at low current densities, whereas at high current densities the process is dominated by the series resistance. Very good reproducibility was observed for the junction characteristics.