Cu-In-Te based thin films were grown onto soda-lime glass (SLG) substrates at 200 degrees C by co-evaporation using a molecular beam epitaxy system. The microstructural properties were examined by means of scanning electron microscopy, X-ray diffraction and Raman scattering.The crystalline quality of Cu-In-Te based thin films with high Cu/In ratios is superior to that of films with low Cu/In ratios. The films with Cu/In ratios of 0.69 +/- 0.04 exhibited a single chalcopyrite phase with random orientation, whereas a defect chalcopyrite phase with a preferred (112) orientation was obtained for thin films with Cu/In ratios of 0.26 +/- 0.02. However, the films with high Cu/In ratios of 0.69 +/- 0.04 showed nearly constant low resistivity (similar to 10(-2) Omega cm) at temperatures from 80 to 400 K due to high hole concentration (>10(19) cm(-3)), resulting in semi-metallic behavior. The hole conduction mechanism of the film (Cu/In atomic ratios = 0.26 +/- 0.02) with semi-conductive properties was found to be variable-range-hopping of the Mott type in the wide range of 80-300K. The optical bandgaps of Cu-In-Te based thin films are determined to be 0.93-1.02 eV at 300 K from transmission and reflection measurements. A solar cell with a ZnO/CdS/CuIn(3)Te(5)/Mo/SLG structure showed a total area (0.50 cm(2)) efficiency of 5.1% under AM1.5 illumination (100 mW/cm(2)) after light soaking. The conduction band offset at the CdS/CuIn(3)Te(5) interface was estimated to be -0.14 eV from X-ray photoelectron spectroscopy analysis. (C) 2010 Elsevier B.V. All rights reserved.