Article PreviewArticle PreviewArticle PreviewSingle Shockley faults have been studied in 4H-SiC epitaxial layers by using a spatial resolved micro-photoluminescence technique. In particular the Effect of the UV pumping laser has been investigated. We demonstrated that high power density exposition at 325 nm affects drastically the structural properties of the epitaxial layers leading to a growth of this defect. We also demonstrated that by opportunely tuning the power density of the UV laser on the sample it is possible to analyze a wide area without producing any negative effect.