Characterising Strain/Stress and Defects in SiC Wafers Using Raman Imaging

Raman spectroscopy is a well established non-destructive tool for determining crystal polytypes, strain/stress, electronic properties and material quality in SiC. Here we report on the application of ultrafast Raman imaging to a SiC wafer, allowing 870,908 spectra to be collected from a 2 inch 4H-SiC wafer, in 75 minutes. Analysis of the acquired data enabled us to locate and investigate defects and surface contamination and also allowed stress in the wafer to be characterised.