CuInS2 based thin film photovoltaics

A fabrication process for CuInS2 thin film solar cells, based on sulfurization of Cu/In bilayers, is described. The process is investigated by in situ energy dispersive X-ray diffraction for phase identification as a function of process time. It is found that Raman spectroscopy is very convenient and reliable in assessing the quality of CuInS2 produced by this sequential process. Good quality CuInS2 films efficiently collect charge carriers generated by the incident sunlight. The solar-to-electric conversion efficiency limitations of state-of-the-art CuInS2 based devices are discussed using a comparison with device simulation. The module design is laid down and arguments for the up-scaling potential of this new type of solar cell are presented. (C) 2004 Elsevier Ltd. All rights reserved.