The objective of this work was to study the structural and morphological properties of Mo/Cu(In, Ga)Se-2 thin films deposited onto glass substrate by different techniques and thermal treatment in different atmospheres. Electron beam evaporated Mo thin film was better back contact than the sputtered Mo film due to the structural improvements of CIGS film deposited on it. It was also observed that an increase of the grain size and a better morphology for Ar selenized CIGS films than for the vacuum ones. These results could lead to a decrease of the number of defects for Ar selenized CIGS films on evaporated Mo, which could imply an enhancement of the solar cell efficiency. (C) 2004 Elsevier B.V. All rights reserved.