Structure and photovoltaic properties of Ag/p-CuPc/a-Si/c-Si/Ag organic-inorganic hybrid heterojunction fabricated by chemical spray pyrolysis technique

Abstract

This investigation refers to the fabrication of an organic-inorganic hybrid heterojunction photovoltaic device. Heterojunctions PV devices were fabricated by growing p-type organic CuPc films onto inorganic amorphous silicon substrates using chemical spray pyrolysis technique. The structural and morphological properties of the amorphous silicon thin films and CuPc thin films were investigated by XRD, RAMAN and FEG-SEM analysis. The XRD pattern indicated that the films were polycrystalline in nature of CuPc thin films that crystallized in the orthorhombic alpha-phase structure. We determined 17 Raman active peaks belong to CuPc thin films and our results are compatible with polarized Raman spectra. We have characterized the electrical and photovoltaic properties of Ag/p-CuPc/a-Si/c-Si/Ag heterojunction devices. The measured electrical parameters were used to determine the conduction mechanisms of these heterojunctions. Electrical parameters such as barrier height Phi(B), diode ideality factor eta, series resistance R-s and shunt resistance R-sh were determined from the I-V characteristic in the dark conditions for Ag/p-CuPc/a-Si/n-Si/Ag and Ag/p-CuPc/a-Si/p-Si/Ag heterojunctions were found to be 2.5-5.7, 0.95-0.99 eV, 26-28.6 k Omega, and 9.2-3.7 M Omega, respectively. The photovoltaic properties of organic-inorganic hybrid heterojunction devices were evaluated by current-voltage characteristics under illumination. The hybrid heterojunctions shows a photovoltaic behavior and the photovoltaic parameters, such as open circuit voltage and short circuit current were obtained as V-oc = 167 mV and J(sc) = 18.4 mA/m(2), respectively. The Ag/p-CuPc/a-Si/c-Si/Ag hybrid heterojunctions can be using as a heterojunction photovoltaic devices. (c) 2013 Elsevier B.V. All rights reserved.