The non-radiative recombination properties of Cu(In,Ga)Se-2 [CIGS] solar cells were investigated locally through photothermal [PT] measurements by atomic force microscopy under various kinds of incident light with photon energies above or below the bandgap of CIGS. We found that the intensity and spatial distribution of the PT signal strongly depended on the photon energy of the incident light and on the Ga content of the CIGS layer. These results suggest the possibilities that photo-generated free electrons could accumulate near the grain boundary because of the built-in electric field and that sub-gap states with discrete energy levels are present in the CIGS material. (C) 2015 Elsevier B.V. All rights reserved.