Electrical properties of FePc organic semiconductor thin films obtained by CSP technique for photovoltaic applications

Abstract

Iron-phthalocyanine (FePc) organic semiconductor thin films were prepared on Corning glass and c-Si substrates at a substrate temperature of 150 degrees C by a chemical spray pyrolysis (CSP) technique. The structural properties of the FePc thin films were determined by an X-Ray Diffraction (XRD) analysis and Raman Spectroscopy. Surface morphology of FePc films was determined by Scanning Electron Microscopy (SEM). The XRD pattern indicated that the films were microcrystalline in nature of FePc thin films that crystallized in the orthorhombic alpha-phase structure with preferential orientation along the (200) direction. We determined 22 Raman active peaks belonging to FePc thin films and our results are compatible with polarized Raman spectra. The electrical properties of FePc organic thin films were investigated by Hall Effect measurements. The electrical parameters of FePc films such as Carrier concentrations, Conductivity (sigma), Resistivity (rho), Mobility (mu) and Hall coefficient were determined from the Hall measurements at room temperature. The electrical transport and diode parameters of FePc/c-Si organic-inorganic hybrid heterojunctions were investigated by current-voltage (I-V) measurements at room temperature under dark condition. The current-voltage characteristics of FePc/c-Si hybrid heterojunctions demonstrated good rectifying behavior and have good photosensitivity under light conditions. The barrier heights and ideality factor values of FePc/n-Si and FePc/p-Si hybrid heterojunctions were found to be 1.54, 4.07 and 0.97, 1.1 eV, respectively. (C) 2015 Elsevier Ltd. All rights reserved.