Developing Raman scattering as quality control technique: Correlation with presence of electronic defects in CIGS-based devices

One of the limitations of online quality control processes is the inability of detecting electronic defects in semiconductor materials. This is particularly important in low cost processes such as electrodeposited Cu(In,Ga)(S,Se)₂ solar cells, due to the large number of inhomogeneities that can be expected. Standard techniques for characterizing electronic defects are not suitable for online control. However, optical techniques such as Raman scattering can be specially suited for online process monitoring applications. In this paper we analyze the correlation between the Raman spectral features and the presence of electronic defects. Our results confirm the potential of Raman spectroscopy for the indirect detection of point defects which are important for device performance.