We report a study of the interface between fullerene (C-60) doped polycarbonate (PC) blends and n-type Si substrate. C-60 is usually an electron acceptor in interpenetrated networks and an electron transport in photovoltaic cells. We have studied that the guest-host approach to prepare C-60 doped polycarbonate blend. In this article, we report the I-V characteristics of C-60 doped polycarbonate/n-type Si junction and the annealing effect on these characteristics. In this junction, a nanocomposite of organic semiconductor fullerene (C-60), used as the active medium, with an inert polycarbonate matrix was spin coated on n-type Si substrate. We found that the C-60 shows the junction characteristics with n-type Si substrate. The knee voltage and dynamic resistance varies with concentration of C-60 as well as temperature. Ellipsometry studies showed the annealing effect on the refractive index and thickness of C-60 doped polycarbonate blend on n-type Si substrate. The optical micrographs show that fullerene (C-60) is spherical molecule and it is blend in the form of crystallites having size of micron order. (C) 2009 Elsevier B. V. All rights reserved.