Current-voltage (I-V) characteristics of regioregular (head-tail) poly(3-hexylthiophene), HT-PHT films in the sandwich cell structure of Al/HT-PHT/Au have been studied as a function of temperature. The cells showed typical rectification characteristics with the ratio of more than 10(3), indicating the formation of the Schottky type junction at the interface of Al/HT-PHT. The temperature dependence of I-V characteristics at the forward biases are discussed with the bulk property of the HT-PHT. The reversed current and its characteristics are discussed taking the thermionic emission and diffusion models at the junctions of Al/HT-PHT into consideration. (C) 2002 Elsevier Science B.V. All rights reserved.