We fabricated inorganic/organic hybrid solar cells consisting of a p-type Cu2O layer and a fullerene derivative (PCBM) layer, which were prepared by wet processes. The Cu2O layer was grown by electrochemical deposition from an alkaline solution (pH 12.5) containing copper (II) sulfate and lactic acid. A PCBM layer was deposited on it by spin-casting a solution of PCBM. The optimized solar cell showed short circuit current density of 1.5 mA/cm(2), open circuit voltage of 0.4 V, and overall power conversion efficiency of 0.095% under the condition of AM 1.5 G (100 mW/cm(2)). Improvement in mobility and lifetime of electrons in the Cu2O layer is considered to be the key to increase efficiency further. (c) 2012 Elsevier B.V. All rights reserved.