Quality assessment of chalcopyrite thin films using Raman spectroscopy

The relationship of the linewidth of the Raman A1-mode of CuInS2-based thin films is investigated. Thereby it is assumed that the linewidth is predictive for the crystal quality. Comparison with the parameters of the solar cells formed out of these thin films reveal a direct correlation between the linewidth and solar cell data, such as open circuit voltage and fill factor. A correlation of the linewidth with the crystal sizes as determined by SE images is also found. For small linewidths, a saturation of the solar cell data is found. This behaviour indicates other origins of performance limitation to be present in CuInS2-based devices.