Advances in defect characterization techniques using polarized light observation in SiC wafers for power devices

• Polarized light observation techniques enable non-destructive defect analysis in SiC wafers. • Combination of polarized light and X-ray topography allows detailed evaluation of threading dislocations. • The XS-1 Sirius system enables rapid and comprehensive defect inspection for 6-inch and 8-inch SiC wafers. • Visualization of in-plane shear stress in threading dislocations is achieved using a slight rotation of the analyzer. • These advancements contribute to improved quality control and productivity in SiC power device manufacturing. This short review provides an overview of advancements in the characterization of defects in silicon carbide (SiC) wafers using polarized light observation. SiC, which has a wide bandgap and excellent thermal and electrical properties, is widely used in power devices. However, various defects such as threading screw dislocations (TSD), threading edge dislocations (TED), and basal plane dislocations (BPD) can significantly affect device performance and reliability. Polarized light observation offers a nondestructive method for visualizing these defects and analyzing the stress fields induced within the SiC crystal structure. This paper summarizes recent developments in this technique, including the application of analyzer rotation to enhance the contrast in defect visualization. Furthermore, the development of automated systems for rapid wafer evaluation is discussed, highlighting the role of polarized light observation in improving quality control and production efficiency in SiC power device manufacturing.