Cross strategy of surface and volume characterizations of chalcogenides thin films: Practical case of CIGS absorbers

Photovoltaic cells based on chalcogenides CIGS (Cu(In, Ga)Se2) thin films are a very promising technology. To improve cells performances, a fine optimization of the CIGS absorber properties is needed. Hence, we developed a cross strategy method combining the surface, volume and specific interfaces of the final device characterizations. These features deal with a large panel of physico-chemical techniques for the chemical composition (XPS, EDS, ICP-OES, GD-OES, AES), the morphology (SEM, AFM) and the optical parameters (spectroscopic ellipsometry) determination. This article demonstrates the crucial interest of this cross strategy on CIGS absorbers and focus on the accuracy and complementarities of each technique.